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Sample records for highly reducing conditions

  1. A strategy for reducing neonatal mortality at high altitude using oxygen conditioning.

    PubMed

    West, J B

    2015-11-01

    Neonatal mortality increases with altitude. For example, in Peru the incidence of neonatal mortality in the highlands has been shown to be about double that at lower altitudes. An important factor is the low inspired PO2 of newborn babies. Typically, expectant mothers at high altitude will travel to low altitude to have their babies if possible, but often this is not feasible because of economic factors. The procedure described here raises the oxygen concentration in the air of rooms where neonates are being housed and, in effect, this means that both the mother and baby are at a much lower altitude. Oxygen conditioning is similar to air conditioning except that the oxygen concentration of the air is increased rather than the temperature being reduced. The procedure is now used at high altitude in many hotels, dormitories and telescope facilities, and has been shown to be feasible and effective.

  2. Assessing the Behavior of Typically Lithophile Elements Under Highly Reducing Conditions Relevant to the Planet Mercury

    NASA Technical Reports Server (NTRS)

    Rowland, Rick, II; Vander Kaaden, Kathleen E.; McCubbin, Francis M.; Danielson, Lisa R.

    2017-01-01

    With the data returned from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, there are now numerous constraints on the physical and chemical properties of Mercury, including its surface composition (e.g., Evans et al. 2012; Nittler et al. 201 l; Peplowski et al. 2012; Weider et al. 2012). The high Sand low FeO contents observed from MESSENGER on the planet's surface suggests a low oxygen fugacity of the present planetary materials. Estimates of the oxygen fugacity for Mercurian magmas are approximately 3- 7 log units below the Iron-Wiistite (Fe-FeO) oxygen buffer (McCubbin et al. 2012; Zolotov et al. 2013), several orders of magnitude more reducing than other terrestrial bodies we have data from such as the Earth, Moon, or Mars (Herd 2008; Sharp, McCubbin, and Shearer 2013; Wadhwa 2008). Most of our understanding of elemental partitioning behavior comes from observations made on terrestrial rocks, but Mercury's oxygen fugacity is far outside the conditions of those samples. With limited oxygen available, lithophile elements may instead exhibit chalcophile, halophile, or siderophile behaviors. Furthermore, very few natural samples of rocks that formed under reducing conditions are available in our collections (e.g., enstatite chondrites, achondrites, aubrites). The goal of this study is to conduct experiments at high pressure and temperature conditions to determine the elemental partitioning behavior of typically lithophile elements as a function of decreasing oxygen fugacity.

  3. Assessing the Behavior of Typically Lithophile Elements Under Highly Reducing Conditions Relevant to the Planet Mercury

    NASA Technical Reports Server (NTRS)

    Rowland, Rick, II; Vander Kaaden, Kathleen E.; McCubbin, Francis M.; Danielson, Lisa R.

    2017-01-01

    With the data returned from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission, there are now numerous constraints on the physical and chemical properties of Mercury, including its surface composition. The high Sand low FeO contents observed from MESSENGER suggest a low oxygen fugacity of the present materials on the planet's surface. Most of our understanding of elemental partitioning behavior comes from observations made on terrestrial rocks, but Mercury's oxygen fugacity is far outside the conditions of those samples, estimated at approximately 3-7 log units below the Iron-Wtistite (lW) oxygen buffer, several orders of magnitude more reducing than other terrestrial bodies we have data from. With limited oxygen available, lithophile elements may instead exhibit chalcophile, halophile, or siderophile behaviors. Furthermore, very few natural samples of rocks that formed under reducing conditions (e.g., enstatite chondrites, achondrites, aubrites) are available in our collections for examination of this change in geochemical affinity. Our goal is to determine the elemental partitioning behavior of typically lithophile elements at lower oxygen fugacity as a function of temperature and pressure. Experiments were conducted at I GPa in a 13 mm QUICKpress piston cylinder and at 4 GPa in an 880-ton multianvil press, at temperatures up to 1850degC. The composition of starting materials for the experiments were designed so the final run products contained metal, silicate melt, and sulfide melt phases. Oxygen fugacity was controlled in the experiments by adding silicon metal to the samples, in order to utilize the Si-Si02 buffer, which is approximately 5 log units more reducing than the IW buffer at our temperatures of interest. The target silicate melt composition was diopside (CaMgSi206) because measured surface compositions indicate partial melting of a pyroxene-rich mantle. The results of our experiments will aid in our understanding of

  4. Assessing the Behavior of Typically Lithophile Elements Under Highly Reducing Conditions Relevant to the Planet Mercury

    NASA Technical Reports Server (NTRS)

    Rowland, Rick, II; Vander Kaaden, Kathleen E.; McCubbin, Francis M.; Danielson, Lisa R.

    2017-01-01

    With the data returned from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (lvtESSENGER) mission, there are now numerous constraints on the physical and chemical properties of Mercury, including its surface composition. The high S and low FeO contents observed from MESSENGER suggest a low oxygen fugacity of the present materials on the planet's surface. Most of our understanding of elemental partitioning behavior comes from observations made on terrestrial rocks, but Mercury's oxygen fugacity is far outside the conditions of those samples, estimated at approximately 3-7 log units below the Iron-Wustite (lW) oxygen buffer, several orders of magnitude more reducing than other terrestrial bodies we have data from. With limited oxygen available, lithophile elements may instead exhibit chalcophile, halophile, or siderophile behaviors. Furthermore, very few natural samples of rocks that formed under reducing conditions (e.g., enstatite chondrites, achondrites, aubrites) are available in our collections for examination of this change in geochemical affinity. Our goal is to determine the elemental partitioning behavior of typically lithophile elements at lower oxygen fugacity as a function of temperature and pressure. Experiments were conducted at I GPa in a 13 mm QUICKpress piston cylinder and at 4 GPa in an 880-ton multi-anvil press, at temperatures up to 1850 C. The composition of starting materials for the experiments were designed so the final run products contained metal, silicate melt, and sulfide melt phases. Oxygen fugacity was controlled in the experiments by adding silicon metal to the samples, in order to utilize the Si-Si02 buffer, which is approx. 5 log units more reducing than the IW buffer at our temperatures of interest. The target silicate melt composition was diopside (CaMgSi206) because measured surface compositions indicate partial melting of a pyroxene-rich mantle. The results of our experiments will aid in our understanding of the

  5. Reduced Volume of the Arcuate Fasciculus in Adults with High-Functioning Autism Spectrum Conditions

    PubMed Central

    Moseley, Rachel L.; Correia, Marta M.; Baron-Cohen, Simon; Shtyrov, Yury; Pulvermüller, Friedemann; Mohr, Bettina

    2016-01-01

    Atypical language is a fundamental feature of autism spectrum conditions (ASC), but few studies have examined the structural integrity of the arcuate fasciculus, the major white matter tract connecting frontal and temporal language regions, which is usually implicated as the main transfer route used in processing linguistic information by the brain. Abnormalities in the arcuate have been reported in young children with ASC, mostly in low-functioning or non-verbal individuals, but little is known regarding the structural properties of the arcuate in adults with ASC or, in particular, in individuals with ASC who have intact language, such as those with high-functioning autism or Asperger syndrome. We used probabilistic tractography of diffusion-weighted imaging to isolate and scrutinize the arcuate in a mixed-gender sample of 18 high-functioning adults with ASC (17 Asperger syndrome) and 14 age- and IQ-matched typically developing controls. Arcuate volume was significantly reduced bilaterally with clearest differences in the right hemisphere. This finding remained significant in an analysis of all male participants alone. Volumetric reduction in the arcuate was significantly correlated with the severity of autistic symptoms as measured by the Autism-Spectrum Quotient. These data reveal that structural differences are present even in high-functioning adults with ASC, who presented with no clinically manifest language deficits and had no reported developmental language delay. Arcuate structural integrity may be useful as an index of ASC severity and thus as a predictor and biomarker for ASC. Implications for future research are discussed. PMID:27242478

  6. High-temperature vaporization of B2O3(l) under reducing conditions.

    PubMed

    Jacobson, Nathan S; Myers, Dwight L

    2011-11-17

    The vaporization of B(2)O(3) in a reducing environment leads to the formation of both B(2)O(3)(g) and B(2)O(2)(g). Whereas the formation of B(2)O(3)(g) is well understood, many questions about the formation of B(2)O(2)(g) remain. Previous studies using B(s) + B(2)O(3)(l) have led to inconsistent thermodynamic data. In this study, it was found that, after heating, B(s) and B(2)O(3)(l) appeared to separate and variations in contact area likely led to the inconsistent vapor pressures of B(2)O(2)(g). To circumvent this problem, the activity of boron was fixed with a two-phase mixture of FeB and Fe(2)B. Both second- and third-law enthalpies of formation were measured for B(2)O(2)(g) and B(2)O(3)(g). From these values, the enthalpies of formation at 298.15 K were calculated to be -479.9 ± 25.7 kJ/mol for B(2)O(2)(g) and -833.4 ± 13.1 kJ/mol for B(2)O(3)(g). Ab initio calculations to determine the enthalpies of formation of B(2)O(2)(g) and B(2)O(3)(g) were conducted using the W1BD composite method and showed good agreement with the experimental values.

  7. Microscale imaging and identification of Fe speciation and distribution during fluid-mineral reactions under highly reducing conditions.

    PubMed

    Mayhew, L E; Webb, S M; Templeton, A S

    2011-05-15

    The oxidation state, speciation, and distribution of Fe are critical determinants of Fe reactivity in natural and engineered environments. However, it is challenging to follow dynamic changes in Fe speciation in environmental systems during progressive fluid-mineral interactions. Two common geological and aquifer materials-basalt and Fe(III) oxides-were incubated with saline fluids at 55 °C under highly reducing conditions maintained by the presence of Fe(0). We tracked changes in Fe speciation after 48 h (incipient water-rock reaction) and 10 months (extensive water-rock interaction) using synchrotron-radiation μXRF maps collected at multiple energies (ME) within the Fe K-edge. Immediate PCA analysis of the ME maps was used to optimize μXANES analyses; in turn, refitting the ME maps with end-member XANES spectra enabled us to detect and spatially resolve the entire variety of Fe-phases present in the system. After 48 h, we successfully identified and mapped the major Fe-bearing components of our samples (Fe(III) oxides, basalt, and rare olivine), as well as small quantities of incipient brucite associated with olivine. After 10 months, the Fe(III)-oxides remained stable in the presence of Fe(0), whereas significant alteration of basalt to minnesotaite and chlinochlore had occurred, providing new insights into heterogeneous Fe speciation in complex geological media under highly reducing conditions.

  8. Effects of temperature on anaerobic decomposition of high-molecular weight organic matter under sulfate-reducing conditions

    NASA Astrophysics Data System (ADS)

    Matsui, Takato; Kojima, Hisaya; Fukui, Manabu

    2013-03-01

    Most sedimentary mineralization occurs along coasts under anaerobic conditions. In the absence of oxygen, high-molecular weight organic matter in marine sediments is gradually decomposed by hydrolysis, fermentation and sulfate reduction. Because of the different responses of the respective steps to temperature, degradation may be specifically slowed or stopped in certain step. To evaluate the effect of temperature on cellobiose degradation, culture experiments were performed at six different temperatures (3 °C, 8 °C, 13 °C, 18 °C, 23 °C, and 28 °C) under sulfate-reducing conditions. This study measured the concentrations of sulfide, dissolved organic carbon (DOC), and organic acids during that degradation. Degradation patterns were divided into three temperature groups: 3 °C, 8/13 °C, and 18/23/28 °C. The decrease in DOC proceeded in two steps, except at 3 °C. The length of the stagnant phase separating these two steps differed greatly between temperatures of 8/13 °C and 18/23/28 °C. In the first step, organic carbon was consumed by hydrolysis, fermentation and sulfate reduction. In the second step, acetate accumulated during the first step was oxidized by sulfate reduction. Bacterial communities in the cultures were analyzed by denaturing gradient gel electrophoresis (DGGE); the major differences among the three temperature groups were attributed to shifts in acetate-using sulfate reducers of the genus Desulfobacter. This suggests that temperature characteristics of dominant acetate oxidizers are important factors in determining the response of carbon flow in coastal marine sediments in relation to the changes in temperature.

  9. No improvement of survival with reduced- versus high-intensity conditioning for allogeneic stem cell transplants in Ewing tumor patients.

    PubMed

    Thiel, U; Wawer, A; Wolf, P; Badoglio, M; Santucci, A; Klingebiel, T; Basu, O; Borkhardt, A; Laws, H-J; Kodera, Y; Yoshimi, A; Peters, C; Ladenstein, R; Pession, A; Prete, A; Urban, E-C; Schwinger, W; Bordigoni, P; Salmon, A; Diaz, M A; Afanasyev, B; Lisukov, I; Morozova, E; Toren, A; Bielorai, B; Korsakas, J; Fagioli, F; Caselli, D; Ehninger, G; Gruhn, B; Dirksen, U; Abdel-Rahman, F; Aglietta, M; Mastrodicasa, E; Torrent, M; Corradini, P; Demeocq, F; Dini, G; Dreger, P; Eyrich, M; Gozdzik, J; Guilhot, F; Holler, E; Koscielniak, E; Messina, C; Nachbaur, D; Sabbatini, R; Oldani, E; Ottinger, H; Ozsahin, H; Schots, R; Siena, S; Stein, J; Sufliarska, S; Unal, A; Ussowicz, M; Schneider, P; Woessmann, W; Jürgens, H; Bregni, M; Burdach, S

    2011-07-01

    Outcomes of Ewing tumor (ET) patients treated with allogeneic stem cell transplantation (allo-SCT) were compared regarding the use of reduced-intensity conditioning (RIC) and high-intensity conditioning (HIC) regimens as well as human leukocyte antigen (HLA)-matched and HLA-mismatched grafts. We retrospectively analyzed data of 87 ET patients from the European Group for Blood and Marrow Transplantation, Pediatric Registry for Stem Cell Transplantations, Asia Pacific Blood and Marrow Transplantation and MetaEICESS registries treated with allo-SCT. Fifty patients received RIC (group A) and 37 patients received HIC (group B). Twenty-four patients received HLA-mismatched grafts and 63 received HLA-matched grafts. Median overall survival was 7.9 months [±1.24, 95% confidence interval (CI) 5.44-10.31] for group A and 4.4 months (±1.06, 95% CI 2.29-6.43) for group B patients (P = 1.3). Death of complications (DOC) occurred in 4 of 50 (0.08) and death of disease (DOD) in 33 of 50 (0.66) group A and in 16 of 37 (0.43) and 17 of 37 (0.46) group B patients, respectively. DOC incidence was decreased (P < 0.01) and DOD/relapse increased (P < 0.01) in group A compared with group B. HLA mismatch was not generally associated with graft-versus-Ewing tumor effect (GvETE). There was no improvement of survival with RIC compared with HIC due to increased DOD/relapse incidence after RIC despite less DOC incidence. This implicates general absence of a clinically relevant GvETE with current protocols.

  10. Mass balance research for high electrochemical performance direct methanol fuel cells with reduced methanol crossover at various operating conditions

    NASA Astrophysics Data System (ADS)

    Park, Jun-Young; Lee, Jin-Hwa; Kang, SangKyun; Sauk, Jun-Ho; Song, Inseob

    Mass balance research in direct methanol fuel cells (DMFCs) provides a more practical method in characterizing the mass transport phenomena in a membrane electrode assembly (MEA). This method can be used to measure methanol utilization efficiency, water transport coefficient (WTC), and methanol to electricity conversion rate of a MEA in DMFCs. First, the vital design parameters of a MEA are recognized for achieving high methanol utilization efficiency with increased power density. In particular, the structural adjustment of anode diffusion layer by adding microporous layer (MPL) is a very effective way to decrease WTC with reduced methanol crossover due to the mass transfer limitation in the anode. On the other hand, the cathode MPL in the MEA design can contribute in decreasing methanol crossover. The change of structure of cathode diffusion layer is also found to be a very effective way in improving power density. In contrast, the WTC of DMFC MEAs remains virtually constant in the range of 3.4 and 3.6 irrespective of the change of the cathode GDL. The influence of operating condition on the methanol utilization efficiency, WTC, and methanol to electricity conversion rate is also presented and it is found that these mass balance properties are strongly affected by temperature, current density, methanol concentration, and the stoichiometry of fuel and air.

  11. The Role of Carbon in Core Formation Under Highly Reducing Conditions With Implications for the Planet Mercury

    NASA Technical Reports Server (NTRS)

    Vander Kaaden, Kathleen E..; McCubbin, Francis M.; Ross, D. Kent; Draper, David S.

    2017-01-01

    Results from the MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER) spacecraft have shown elevated abundances of carbon on the surface of Mercury. Furthermore, the X-Ray Spectrometer on board MESSENGER measured elevated abundances of sulfur and low abundances of iron, suggesting the planet's oxygen fugacity (fO2) is several log10 units below the Iron-Wüstite (IW) buffer. Similar to the role of other volatiles (e.g. sulfur) on highly reducing planetary bodies, carbon is expected to behave differently than it would under higher fO2. As discussed by Nittler et al. and Hauck et al., under such highly reducing conditions, the majority of the iron partitions into the core. On Mercury, this resulted in a relatively large core and a thin mantle. Using a composition similar to the largest volcanic field on the planet (the northern volcanic plains), Vander Kaaden and McCubbin conducted sink-float experiments to determine the density of melts and minerals on Mercury. They showed that graphite would be the only buoyant mineral in a mercurian magma ocean. Therefore, Vander Kaaden and McCubbin proposed a possible primary flotation crust on the planet composed of graphite. Concurrently, Peplowski et al. used GRS data from MESSENGER to show an average northern hemisphere abundance of C on the planet of 1.4 +/- 0.9 wt%. However, as this result was only at the one-sigma detection limit, possible carbon abundances at the three-sigma detection limit for Mercury range from 0 to 4.1 wt% carbon. Additionally, Murchie et al. investigated the possible darkening agent on Mercury and concluded that coarse-grained graphite could darken high reflectance plains to the low reflectance material. To further test the possibility of elevated abundances of carbon in Mercury's crust, Peplowski et al. used the low-altitude MESSENGER data to show that carbon is the only material consistent with both the visible to near-infrared spectra and the neutron measurements of low

  12. Combustion at reduced gravitational conditions

    NASA Technical Reports Server (NTRS)

    Berlad, A. L.; Wang, L. S.; Joshi, N.; Pai, C. I.

    1980-01-01

    The theoretical structures needed for the predictive analyses and interpretations for flame propagation and extinction for clouds of porous particulates are presented. Related combustion theories of significance to reduced gravitational studies of combustible media are presented. Nonadiabatic boundaries are required for both autoignition theory and for extinction theory. Processes that were considered include, pyrolysis and vaporization of particulates, heterogeneous and homogeneous chemical kinetics, molecular transport of heat and mass, radiative coupling of the medium to its environment, and radiative coupling among particles and volume elements of the combustible medium.

  13. Heat and Momentum Transfer Studies in High Reynolds Number Wavy Films at Normal and Reduced Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Balakotaiah, V.

    1996-01-01

    We examined the effect of the gas flow on the liquid film when the gas flows in the countercurrent direction in a vertical pipe at normal gravity conditions. The most dramatic effect of the simultaneous flow of gas and liquid in pipes is the greatly increased transport rates of heat, mass, and momentum. In practical situations this enhancement can be a benefit or it can result in serious operational problems. For example, gas-liquid flow always results in substantially higher pressure drop and this is usually undesirable. However, much higher heat transfer coefficients can be expected and this can obviously be of benefit for purposes of design. Unfortunately, designers know so little of the behavior of such two phase systems and as a result these advantages are not utilized. Due to the complexity of the second order boundary model as well as the fact that the pressure variation across the film is small compared to the imposed gas phase pressure, the countercurrent gas flow affect was studied for the standard boundary layer model. A different stream function that can compensate the shear stress affect was developed and this stream function also can predict periodic solutions. The discretized model equations were transformed to a traveling wave coordinate system. A stability analysis of these sets of equations showed the presence of a Hopf bifurcation for certain values of the traveling wave velocity and the shear stress. The Hopf celerity was increased due to the countercurrent shear. For low flow rate the increases of celerity are more than for the high flow rate, which was also observed in experiments. Numerical integration of a traveling wave simplification of the model also predicts the existence of chaotic large amplitude, nonperiodic waves as observed in the experiments. The film thickness was increased by the shear.

  14. Distinguishing iron-reducing from sulfate-reducing conditions

    USGS Publications Warehouse

    Chapelle, F.H.; Bradley, P.M.; Thomas, M.A.; McMahon, P.B.

    2009-01-01

    Ground water systems dominated by iron- or sulfate-reducing conditions may be distinguished by observing concentrations of dissolved iron (Fe2+) and sulfide (sum of H2S, HS-, and S= species and denoted here as "H2S"). This approach is based on the observation that concentrations of Fe2+ and H2S in ground water systems tend to be inversely related according to a hyperbolic function. That is, when Fe2+ concentrations are high, H2S concentrations tend to be low and vice versa. This relation partly reflects the rapid reaction kinetics of Fe2+ with H2S to produce relatively insoluble ferrous sulfides (FeS). This relation also reflects competition for organic substrates between the iron- and the sulfate-reducing microorganisms that catalyze the production of Fe2+ and H 2S. These solubility and microbial constraints operate in tandem, resulting in the observed hyperbolic relation between Fe2+ and H 2S concentrations. Concentrations of redox indicators, including dissolved hydrogen (H2) measured in a shallow aquifer in Hanahan, South Carolina, suggest that if the Fe2+/H2S mass ratio (units of mg/L) exceeded 10, the screened interval being tapped was consistently iron reducing (H2 ???0.2 to 0.8 nM). Conversely, if the Fe 2+/H2S ratio was less than 0.30, consistent sulfate-reducing (H2 ???1 to 5 nM) conditions were observed over time. Concomitantly high Fe2+ and H2S concentrations were associated with H2 concentrations that varied between 0.2 and 5.0 nM over time, suggesting mixing of water from adjacent iron- and sulfate-reducing zones or concomitant iron and sulfate reduction under nonelectron donor-limited conditions. These observations suggest that Fe2+/H2S mass ratios may provide useful information concerning the occurrence and distribution of iron and sulfate reduction in ground water systems. ?? 2009 National Ground Water Association.

  15. Highly reducing conditions during core formation on Mercury: Implications for internal structure and the origin of a magnetic field

    NASA Astrophysics Data System (ADS)

    Malavergne, Valérie; Toplis, Michael J.; Berthet, Sophie; Jones, John

    2010-03-01

    The high average density and low surface FeO content of the planet Mercury are shown to be consistent with very low oxygen fugacity during core segregation, in the range 3-6 log units below the iron-wüstite buffer. These low oxygen fugacities, and associated high metal content, are characteristic of high-iron enstatite (EH) and Bencubbinite (CB) chondrites, raising the possibility that such materials may have been important building blocks for this planet. With this idea in mind we have explored the internal structure of a Mercury sized planet of EH or CB bulk composition. Phase equilibria in the silicate mantle have been modeled using the thermodynamic calculator p-MELTS, and these simulations suggest that orthopyroxene will be the dominant mantle phase for both EH and CB compositions, with crystalline SiO 2 being an important minor phase at all pressures. Simulations for both compositions predict a plagioclase-bearing "crust" at low pressure, significant clinopyroxene also being calculated for the CB bulk composition. Concerning the core, comparison with recent high pressure and high temperature experiments relevant to the formation of enstatite meteorites, suggest that the core of Mercury may contain several wt.% silicon, in addition to sulfur. In light of the pressure of the core-mantle boundary on Mercury (˜7 GPa) and the pressure at which the immiscibility gap in the system Fe-S-Si closes (˜15 GPa) we suggest that Mercury's core may have a complex shell structure comprising: (i) an outer layer of Fe-S liquid, poor in Si; (ii) a middle layer of Fe-Si liquid, poor in S; and (iii) an inner core of solid metal. The distribution of heat-producing elements between mantle and core, and within a layered core have been quantified. Available data for Th and K suggest that these elements will not enter the core in significant amounts. On the other hand, for the case of U both recently published metal/silicate partitioning data, as well as observations of U

  16. Towards a high thermoelectric performance in rare-earth substituted SrTiO3: effects provided by strongly-reducing sintering conditions.

    PubMed

    Kovalevsky, A V; Yaremchenko, A A; Populoh, S; Thiel, P; Fagg, D P; Weidenkaff, A; Frade, J R

    2014-12-28

    Donor-substituted strontium titanate ceramics demonstrate one of the most promising performances among n-type oxide thermoelectrics. Here we report a marked improvement of the thermoelectric properties in rare-earth substituted titanates Sr0.9R0.1TiO3±δ (R = La, Ce, Pr, Nd, Sm, Gd, Dy, Y) to achieve maximal ZT values of as high as 0.42 at 1190 K < T < 1225 K, prepared via a conventional solid state route followed by sintering under strongly reducing conditions (10%H2-90%N2, 1773 K). As a result of complex defect chemistry, both electrical and thermal properties were found to be dependent on the nature of the rare-earth cation and exhibit an apparent correlation with the unit cell size. High power factors of 1350-1550 μW m(-1) K(-2) at 400-550 K were observed for R = Nd, Sm, Pr and Y, being among the largest reported so far for n-type conducting bulk-ceramic SrTiO3-based materials. Attractive ZT values at high temperatures arise primarily from low thermal conductivity, which, in turn, stem from effective phonon scattering in oxygen-deficient perovskite layers formed upon reduction. The results suggest that highly-reducing conditions are essential and should be employed, whenever possible, in other related micro/nanostructural engineering approaches to suppress the thermal conductivity in target titanate-based ceramics.

  17. High voltage pulse conditioning

    DOEpatents

    Springfield, Ray M.; Wheat, Jr., Robert M.

    1990-01-01

    Apparatus for conditioning high voltage pulses from particle accelerators in order to shorten the rise times of the pulses. Flashover switches in the cathode stalk of the transmission line hold off conduction for a determinable period of time, reflecting the early portion of the pulses. Diodes upstream of the switches divert energy into the magnetic and electrostatic storage of the capacitance and inductance inherent to the transmission line until the switches close.

  18. Fractionated gemtuzumab ozogamicin combined with intermediate-dose cytarabine and daunorubicin as salvage therapy in very high-risk AML patients: a bridge to reduced intensity conditioning transplant?

    PubMed

    Paubelle, Etienne; Ducastelle-Leprêtre, Sophie; Labussière-Wallet, Hélène; Nicolini, Franck Emmanuel; Barraco, Fiorenza; Plesa, Adriana; Salles, Gilles; Wattel, Eric; Thomas, Xavier

    2017-03-01

    Outcome of patients with primary refractory/relapsed (R/R) acute myeloid leukemia (AML) remains dismal. Herein, we present a retrospective monocentric study of 24 very high-risk AML patients who received a combination of fractionated gemtuzumab ozogamicin (GO) with intermediate-dose cytarabine and daunorubicin as salvage therapy. Median age was 55.3 years. Diagnostic was secondary AML for 33% of them. Seven patients had favorable risk, 8 had intermediate-1 or intermediate-2, and 6 had unfavorable risk of AML according to the European LeukemiaNet prognostic index. Complete remission was achieved in 50% of cases (46% in refractory and 55% in relapsed AML) without excessive toxicity. Thirteen patients could be referred for transplant. Only allogeneic hematopoietic stem cell transplantation provided a benefit in this patient cohort with a 1-year overall survival of 50.7 versus 18.1% in the absence of transplantation. Patients treated with reduced intensity conditioning (RIC) showed a longer survival as compared to those undergoing myeloablative conditioning regimen mainly because of decreased toxicity.Our data suggest that salvage therapy with fractionated GO combined with intermediate-dose cytarabine and daunorubicin in very high-risk patients may serve as a potential bridge therapy to RIC transplant.

  19. Long-Term Alcohol Drinking Reduces the Efficacy of Forced Abstinence and Conditioned Taste Aversion in Crossed High-Alcohol Preferring Mice

    PubMed Central

    O’Tousa, David Scott; Grahame, Nicholas Joseph

    2016-01-01

    Background Negative outcomes of alcoholism are progressively more severe as the duration of problem alcohol use increases. Additionally, alcoholics demonstrate tendencies to neglect negative consequences associated with drinking and/or to choose to drink in the immediate presence of warning factors against drinking. The recently derived crossed High-Alcohol Preferring (cHAP) mice, which volitionally drink to heavier intoxication (as assessed by BEC) than other alcohol-preferring populations, as well as spontaneously escalating their intake, may be a candidate to explore mechanisms underlying long-term excessive drinking. Here we hypothesized that an extended drinking history would reduce the ability of two manipulations (forced abstinence and conditioned taste aversion) to attenuate drinking. Methods Experiment 1 examined differences between groups drinking for either 14 or 35 days, half of each subjected to 7 days of forced abstinence and half not, to characterize potential changes in post-abstinence drinking resulting from an extended drinking history. Experiment 2 used a conditioned taste aversion procedure to assess stimulus specificity of the ability of an aversive flavorant to decrease alcohol consumption. Experiment 3 used this taste aversion procedure to assess differences among groups drinking for 1, 14, or 35 days in their propensity to overcome this aversion when the flavorant was mixed with either ethanol or water. Results Experiment 1 demonstrated that although forced abstinence decreased alcohol consumption in mice with a 14-day drinking history, it failed to do so in mice drinking alcohol for 35 days. Experiment 2 showed that the addition of a flavorant only suppressed alcohol drinking if an aversion to the flavorant was previously established. Experiment 3 demonstrated that an extended drinking history expedited extinction of suppressed alcohol intake caused by a conditioned aversive flavor. Conclusions These data show that a history of long

  20. Improving the cycle life of lead-acid batteries using three-dimensional reduced graphene oxide under the high-rate partial-state-of-charge condition

    NASA Astrophysics Data System (ADS)

    Long, Qunying; Ma, Guozheng; Xu, Qiqin; Ma, Cheng; Nan, Junmin; Li, Aiju; Chen, Hongyu

    2017-03-01

    A three-dimensional reduced graphene oxide (3D-RGO) material has been successfully prepared by a facile hydrothermal method and is employed as the negative additive to curb the sulfation of lead-acid battery. When added with 1.0 wt% 3D-RGO, the initial discharge capacity (0.05 C, 185.36 mAh g-1) delivered by the battery is 14.46% higher than that of the control cell (161.94 mAh g-1); and the cycle life under the high-rate partial-state-of-charge (HRPSoC) condition is significantly improved by more than 224% from 8142 to 26,425 cycles. In comparison to the conventional carbon additions like the activated carbon and acetylene black, the 3D-RGO also exhibits the highest initial discharge capacity, the best rate capabilities and the longest HRPSoC cycling life. Finally, we propose a possible mechanism for 3D-RGO to suppress lead-acid battery sulfation, where the abundant pore structure and excellent conductivity of 3D-RGO may have a synergistic effect on facilitating the charge and discharge process of negative plate.

  1. Bioremediation of coal contaminated soil under sulfate-reducing condition.

    PubMed

    Kuwano, Y; Shimizu, Y

    2006-01-01

    The objective of this study was to investigate the biodegradation of coal-derived hydrocarbons, especially high molecular weight (HMW) components, under anaerobic conditions. For this purpose biodegradation experiments were performed, using specifically designed soil column bioreactors. For the experiment, coal-contaminated soil was prepared, which contains high molecular weight hydrocarbons at high concentration (approx. 55.5 mgC g-drysoil(-1)). The experiment was carried out in two different conditions: sulfate reducing (SR) condition (SO4(2-) = 10 mmol l(-1) in the liquid medium) and control condition (SO4(2-)<0.5 mmol l(-1)). Although no degradation was observed under the control condition, the resin fraction decreased to half (from 6,541 to 3,386 mgC g-soil(-1)) under SR condition, with the concomitant increase of two PAHs (phenanthrene and fluoranthene, 9 and 2.5 times, respectively). From these results, we could conclude that high molecular hydrocarbons were biodegradable and transformed to low molecular weight PAHs under the sulfate-reducing condition. Since these PAHs are known to be biologically degraded under aerobic condition, a serial combination of anaerobic (sulfate reducing) and then aerobic bioremediations could be effective and useful for the soil pollution by petroleum and/or coal derived hydrocarbons.

  2. [Reaction of organism to the reduced partial oxygen pressure in inhaled air of highly-qualified female sportsmen in mountain condition].

    PubMed

    Radziievs'kyĭ, P O; Radziievs'ka, M P

    2006-01-01

    Functional respiration system (FRS) state and its changes in highly-qualified sportsmen after decrease of the O2 partial tension (pO2) in inhaled air was investigated. Significant decrease of oxygen regimen efficacy accompanied by alteration of FRS was registered in the first day of altitude hypoxia. In sportsmen well adapted to hypoxia and whose professional activity is associated with low and extremely low pO2 in inhaled air there are no changes in FRS after moving to mountain conditions.

  3. Air Conditioning Does Reduce Air Pollution Indoors

    ERIC Educational Resources Information Center

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  4. Air Conditioning Does Reduce Air Pollution Indoors

    ERIC Educational Resources Information Center

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  5. A mutant of Chlamydomonas without LHCSR maintains high rates of photosynthesis, but has reduced cell division rates in sinusoidal light conditions.

    PubMed

    Cantrell, Michael; Peers, Graham

    2017-01-01

    The LHCSR protein belongs to the light harvesting complex family of pigment-binding proteins found in oxygenic photoautotrophs. Previous studies have shown that this complex is required for the rapid induction and relaxation of excess light energy dissipation in a wide range of eukaryotic algae and moss. The ability of cells to rapidly regulate light harvesting between this dissipation state and one favoring photochemistry is believed to be important for reducing oxidative stress and maintaining high photosynthetic efficiency in a rapidly changing light environment. We found that a mutant of Chlamydomonas reinhardtii lacking LHCSR, npq4lhcsr1, displays minimal photoinhibition of photosystem II and minimal inhibition of short term oxygen evolution when grown in constant excess light compared to a wild type strain. We also investigated the impact of no LHCSR during growth in a sinusoidal light regime, which mimics daily changes in photosynthetically active radiation. The absence of LHCSR correlated with a slight reduction in the quantum efficiency of photosystem II and a stimulation of the maximal rates of photosynthesis compared to wild type. However, there was no reduction in carbon accumulation during the day. Another novel finding was that npq4lhcsr1 cultures underwent fewer divisions at night, reducing the overall growth rate compared to the wild type. Our results show that the rapid regulation of light harvesting mediated by LHCSR is required for high growth rates, but it is not required for efficient carbon accumulation during the day in a sinusoidal light environment. This finding has direct implications for engineering strategies directed at increasing photosynthetic productivity in mass cultures.

  6. Alteration of coffinite under reducing and oxidizing conditions

    NASA Astrophysics Data System (ADS)

    Deditius, Artur P.; Utsunomiya, Satoshi; Pointeau, Veronique; Ewing, Rodney C.

    2010-05-01

    Coffinite, USiO4, is a one of the two naturally occurring actinide silicates (second is thorite, ThSiO4) studied to elucidate the alteration of spent nuclear fuel (SNF) under reducing conditions in a Si-rich environment. In order to understand the stability of coffinite under different redox condition in natural systems, we have investigated coffinite the Grants Uranium Belt, New Mexico, USA (reducing and oxidizing conditions) utilizing a variety of electron microbeam techniques. Fine-grained coffinite (≤10 μm) from Woodrow Mine coexists with carbonate-fluorapatite (CFAp) and (Ca,Sr)-(meta)autunite (M-Aut). It precipitated under reducing conditions replacing CFAp, pyrite and aluminosilicates. Electron-microprobe analyses (EMPA) of coffinite indicate limited incorporation of P2O5 and CaO, below 2.7 and 3.0 wt.%, respectively, into the coffinite structure during replacement of CFAp. The chemical formula of coffinite is (U0.95±0.09Ca0.15±0.02)Σ1.10±0.1(Si0.84±0.08P0.06±0.02)Σ0.90±0.08. Analysis by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) revealed that coffinite initially formed as crystals as large as 100 nm at the edges of altered CFAp. Subsequently, infiltration of (Na,Ba,Sr)-rich oxidizing fluids into fractures resulted in precipitation of Sr-rich M-Aut (up to 4 wt.% of SrO) at the expense of coffinite and CFAp. High-resolution TEM reveals that Na-rich fluids caused a distortion of the ideal coffinite structure and stabilized amorphous domains that formed due to alpha-decay event radiation damage. Subsequently, the Na-enriched amorphous areas of coffinite were preferentially altered, and secondary porosity formed at the scale of ~1 μm. Porosity also was formed during alteration of CFAp to M-Aut, which facilitated the migration of oxidizing fluids over distances of ~150 μm into CFAp, as evidenced by precipitation of M-Aut. These results show that micro-scale dissolution of apatite can create conditions

  7. Oxidation of polycyclic aromatic hydrocarbons under sulfate-reducing conditions

    SciTech Connect

    Coates, J.D.; Anderson, R.T.; Lovley, D.R.

    1996-03-01

    Harbor sediments are commonly contaminated with hydrocarbons from shipping activities, fuel spills, runoff, and inputs from sewage treatment plants. Once in the sediments, PAHs may persist until degraded, resuspened, bioaccummulated, or removed. Microbial metabolism could be expected to have a significant role in removing PAHs from harbor sediments only if PAHs could be degraded under sulfate-reducing or Fe(III)-reducing conditions. This study examines degradation of PAHs under sulfate-reducing conditions. 27 refs., 3 figs.

  8. Reducing Muslim/Arab stereotypes through evaluative conditioning.

    PubMed

    French, Andrea R; Franz, Timothy M; Phelan, Laura L; Blaine, Bruce E

    2013-01-01

    This study replicated and extended Olson and Fazio (2006) by testing whether evaluative conditioning is a means to reduce negative stereotypes about Muslim and other Arab persons. Specifically, evaluative conditioning was hypothesized to lower implicit biases against Muslim and Arab persons. The FreeIAT was used to measure implicit biases. Participants in the evaluative conditioning group showed a significant lowering in implicit biases. Explicit measures of bias were not affected by the conditioning procedure.

  9. Reduced Toxicity High Performance Monopropellant

    DTIC Science & Technology

    2011-09-01

    distribution unlimited Propellant Performance Characteristics LMP - 103S AF-M315E Hydrazine Flame Temperature 1600ºC 1900ºC 600 oC Isp 252 (theor)235 sec...public release; distribution unlimited Compatibility and Handling Propellant LMP - 103S AF-M315E Thruster Materials Compatibility High combustion...detonation Bikini gauges indicate > 103 kPa @ 50ft Fragments thrown > 185 m Punched hole in end cap 12 Distribution A: Approved for public

  10. Microbial mineralization of ethene under sulfate-reducing conditions

    USGS Publications Warehouse

    Bradley, P.M.; Chapelle, F.H.

    2002-01-01

    A limited investigation of the potential for anaerobic ethylene biodegradation under SO4-reducing conditions was performed. Microorganisms indigenous to a lake-bed sediment completely mineralized [1,2-14C] ethylene to 14CO2 when incubated under SO4-reducing conditions. Reliance on ethylene and/or ethane accumulation as a quantitative indicator of complete reductive dechlorination of chloroethylene contaminants may not be warranted. SO4 addition stimulated SO4 reduction as indicated by decreasing SO4 concentrations (> 40% decrease) and production of dissolved sulfide (880 ??M). SO4 amendment completely suppressed the production of ethane and methane. The concomitant absence of ethane and methane production under SO4-amended conditions was consistent with previous conclusions that reduction of ethylene to ethane occurred under methanogenic conditions. A lack of ethylene accumulation under SO4-reducing conditions may reflect insignificant reductive dechlorination of vinyl chloride or efficient anaerobic mineralization of ethylene to CO2.

  11. Reoxidation of Reduced Uranium with Iron(III) (Hydr)Oxides under Sulfate-Reducing Conditions

    SciTech Connect

    Sani, Rajesh K.; Peyton, Brent M.; Dohnalkova, Alice; Amonette, James E.

    2005-03-04

    In cultures of Desulfovibrio desulfuricansG20 the effects of iron(III) (hydr)oxides (hematite, goethite, and ferrihydrite) on microbial reduction and reoxidation of uranium (U) were evaluated under lactate-limited sulfate-reducing conditions. With lactate present, G20 reduced U(VI) in both 1,4-piperazinediethanesulfonate (PIPES) and bicarbonate buffer. Once lactate was depleted, however, microbially reduced U served as an electron donor to reduce Fe(III) present in iron(III) (hydr)oxides. With the same initial amount of Fe(III) (10 mmol/L) for each iron(III) (hydr)oxide,reoxidation of U(IV) was greater with hematite than with goethite or ferrihydrite. As the initial mass loading of hematite increased from 0 to 20 mmol of Fe(III)/L, the rate and extent of U(IV) reoxidation increased. Subsequent addition of hematite [15 mmol of Fe(III)/L] to stationary-phase cultures containing microbially reduced U(IV) also resulted in rapid reoxidation to U(VI). Analysis by U L3-edge X-ray absorption near-edge spectroscopy (XANES) of microbially reduced U particles yielded spectra similar to that of natural uraninite. Observations by high-resolution transmission electron microscopy, selected area electron diffraction, and energy-dispersive X-ray spectroscopic analysis confirmed that precipitated U associated with cells was uraninite with particle diameters of 3-5 nm. By the same techniques, iron sulfide precipitates were found to have a variable Fe and S stoichiometry and were not associated with cells.

  12. Uranium reduction and resistance to reoxidation under iron-reducing and sulfate-reducing conditions.

    PubMed

    Boonchayaanant, Benjaporn; Nayak, Dipti; Du, Xin; Criddle, Craig S

    2009-10-01

    Oxidation and mobilization of microbially-generated U(IV) is of great concern for in situ uranium bioremediation. This study investigated the reoxidation of uranium by oxygen and nitrate in a sulfate-reducing enrichment and an iron-reducing enrichment derived from sediment and groundwater from the Field Research Center in Oak Ridge, Tennessee. Both enrichments were capable of reducing U(VI) rapidly. 16S rRNA gene clone libraries of the two enrichments revealed that Desulfovibrio spp. are dominant in the sulfate-reducing enrichment, and Clostridium spp. are dominant in the iron-reducing enrichment. In both the sulfate-reducing enrichment and the iron-reducing enrichment, oxygen reoxidized the previously reduced uranium but to a lesser extent in the iron-reducing enrichment. Moreover, in the iron-reducing enrichment, the reoxidized U(VI) was eventually re-reduced to its previous level. In both, the sulfate-reducing enrichment and the iron-reducing enrichment, uranium reoxidation did not occur in the presence of nitrate. The results indicate that the Clostridium-dominated iron-reducing communities created conditions that were more favorable for uranium stability with respect to reoxidation despite the fact that fewer electron equivalents were added to these systems. The likely reason is that more of the added electrons are present in a form that can reduce oxygen to water and U(VI) back to U(IV).

  13. Activity of sulfate-reducing bacteria under simulated reservoir conditions

    SciTech Connect

    Rosnes, J.T.; Graue, A.; Lien, T. )

    1991-05-01

    This paper reports on sulfate-reducing bacteria (SRB) that have been isolated from hot oilfield waters from subsea oil reservoirs in the North Sea. Experiments with these bacteria in a reservoir simulator indicate that SRB may maintain their activity in the conditions found in most North Sea reservoirs and, if precautions are not taken, may contribute to souring of the oil and gas.

  14. Anticipatory postural adjustments in conditions of simulated reduced gravity.

    PubMed

    Li, Xiaoyan; Aruin, Alexander S

    2008-11-01

    The study investigates the role of decreased gravity on anticipatory postural adjustments (APAs). Subjects performed fast bilateral arm-raising movements and load releases while in conditions of normal and reduced gravity. Reduced gravity conditions were simulated by changing the ratio between the body weight and mass. Electromyographic (EMG) activity of dorsal and ventral trunk and leg muscles, as well as ground reaction forces, were recorded and quantified within the time intervals typical of APAs. Anticipatory postural adjustments were seen in normal gravity conditions as well as in simulated reduced gravity conditions. However, in decreased gravity conditions, the magnitudes of the anticipatory integrals of electromyography muscle activity (EMG) were smaller compared to normal gravity. Moreover, there was a linear relation between EMG and simulated decreased gravity and between the displacement of the center of pressure (COP) and simulated gravity. The study provides new data on the effect of gravity in feed-forward postural control and stresses the importance of taking into consideration its role in the control of upright posture.

  15. Cytoreductive treatment with clofarabine/ara-C combined with reduced-intensity conditioning and allogeneic stem cell transplantation in patients with high-risk, relapsed, or refractory acute myeloid leukemia and advanced myelodysplastic syndrome.

    PubMed

    Buchholz, Stefanie; Dammann, Elke; Stadler, Michael; Krauter, Juergen; Beutel, Gernot; Trummer, Arne; Eder, Matthias; Ganser, Arnold

    2012-01-01

    The combination of cytoreductive chemotherapy with reduced-intensity conditioning (RIC) is a highly effective antileukemic therapy. Purpose of this retrospective analysis was to evaluate the antileukemic efficacy and toxicity of clofarabine-based chemotherapy followed by RIC and allogeneic stem cell transplantation (SCT) for high-risk, relapsed, or refractory acute myeloid leukemia (AML) or myelodysplastic syndromes (MDS). From May 2007 until October 2009, a total of 27 patients underwent allogeneic SCT after treatment with clofarabine and ara-C for 5d and RIC (4Gy TBI/cyclophosphamide/ATG). Prophylaxis of graft-versus-host disease (GvHD) consisted of cyclosporine and mycophenolate mofetil. Unmanipulated G-CSF mobilized PBSC (n=26) or bone marrow cells (n=1) were transplanted from unrelated (n=21) or matched related (n=6) donors. Non-hematological toxicities of this regimen mainly affected liver and skin and were all reversible. Seven patients relapsed within a median time of 5.7 months. The overall survival (OS) and relapse-free survival rates were 56% and 52% at 2 yr, respectively. In this cohort of patients, cytoreduction with clofarabine/ara-C (ClAraC) followed by RIC allogeneic SCT was well tolerated and showed good antileukemic efficacy even in patients with high-risk AML or MDS, with engraftment and GvHD-incidence comparable to other RIC regimens.

  16. Degradation of 4-n-nonylphenol under nitrate reducing conditions.

    PubMed

    De Weert, Jasperien P A; Viñas, Marc; Grotenhuis, Tim; Rijnaarts, Huub H M; Langenhoff, Alette A M

    2011-02-01

    Nonylphenol (NP) is an endocrine disruptor present as a pollutant in river sediment. Biodegradation of NP can reduce its toxicological risk. As sediments are mainly anaerobic, degradation of linear (4-n-NP) and branched nonylphenol (tNP) was studied under methanogenic, sulphate reducing and denitrifying conditions in NP polluted river sediment. Anaerobic bioconversion was observed only for linear NP under denitrifying conditions. The microbial population involved herein was further studied by enrichment and molecular characterization. The largest change in diversity was observed between the enrichments of the third and fourth generation, and further enrichment did not affect the diversity. This implies that different microorganisms are involved in the degradation of 4-n-NP in the sediment. The major degrading bacteria were most closely related to denitrifying hexadecane degraders and linear alkyl benzene sulphonate (LAS) degraders. The molecular structures of alkanes and LAS are similar to the linear chain of 4-n-NP, this might indicate that the biodegradation of linear NP under denitrifying conditions starts at the nonyl chain. Initiation of anaerobic NP degradation was further tested using phenol as a structure analogue. Phenol was chosen instead of an aliphatic analogue, because phenol is the common structure present in all NP isomers while the structure of the aliphatic chain differs per isomer. Phenol was degraded in all cases, but did not affect the linear NP degradation under denitrifying conditions and did not initiate the degradation of tNP and linear NP under the other tested conditions.

  17. Oxidation of polycyclic aromatic hydrocarbons under sulfate-reducing conditions

    USGS Publications Warehouse

    Coates, J.D.; Anderson, R.T.; Lovley, D.R.

    1996-01-01

    [14C]naphthalene and phenanthrene were oxidized to 14CO2 without a detectable lag under strict anaerobic conditions in sediments from San Diego Bay, San Diego, Calif., that were heavily contaminated with polycyclic aromatic hydrocarbons (PAHs) but not in less contaminated sediments. Sulfate reduction was necessary for PAH oxidation. These results suggest that the self-purification capacity of PAH-contaminated sulfate-reducing environments may be greater than previously recognized.

  18. High Energy Efficiency Air Conditioning

    SciTech Connect

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz

    2003-12-31

    This project determined the performance of a new high efficiency refrigerant, Ikon B, in a residential air conditioner designed to use R-22. The refrigerant R-22, used in residential and small commercial air conditioners, is being phased out of production in developed countries beginning this year because of concerns regarding its ozone depletion potential. Although a replacement refrigerant, R-410A, is available, it operates at much higher pressure than R-22 and requires new equipment. R-22 air conditioners will continue to be in use for many years to come. Air conditioning is a large part of expensive summer peak power use in many parts of the U.S. Previous testing and computer simulations of Ikon B indicated that it would have 20 - 25% higher coefficient of performance (COP, the amount of cooling obtained per energy used) than R-22 in an air-cooled air conditioner. In this project, a typical new R-22 residential air conditioner was obtained, installed in a large environmental chamber, instrumented, and run both with its original charge of R-22 and then with Ikon B. In the environmental chamber, controlled temperature and humidity could be maintained to obtain repeatable and comparable energy use results. Tests with Ikon B included runs with and without a power controller, and an extended run for several months with subsequent analyses to check compatibility of Ikon B with the air conditioner materials and lubricant. Baseline energy use of the air conditioner with its original R-22 charge was measured at 90 deg F and 100 deg F. After changeover to Ikon B and a larger expansion orifice, energy use was measured at 90 deg F and 100 deg F. Ikon B proved to have about 19% higher COP at 90 deg F and about 26% higher COP at 100 deg F versus R-22. Ikon B had about 20% lower cooling capacity at 90 deg F and about 17% lower cooling capacity at 100 deg F versus R-22 in this system. All results over multiple runs were within 1% relative standard deviation (RSD). All of these

  19. TECHNETIUM SORPTION BY CEMENTITIOUS MATERIALS UNDER REDUCING CONDITIONS

    SciTech Connect

    Kaplan, D.; Estes, S.; Arai, Y.; Powell, B.

    2012-01-31

    The objective of this study was to measure Tc sorption to cementitious materials under reducing conditions to simulate Saltstone Disposal Facility conditions. Earlier studies were conducted and the experimental conditions were found not to simulate those of the facility. Through a five month subcontract with Clemson University, sorption of {sup 99}Tc to four cementitious materials was examined within an anaerobic glovebag targeting a 0.1% H2(g)/ 99.9% N{sub 2}(g) atmosphere. Early experiments based on Tc sorption and Eh indicated that 0.1% H{sub 2}(g) (a reductant) was necessary to preclude experimental impacts from O{sub 2}(g) diffusion into the glovebag. Preliminary data to date (up to 56 days) indicates that sorption of {sup 99}Tc to cementitious materials increased with increasing slag content for simulated saltstone samples. This is consistent with the conceptual model that redox active sulfide groups within the reducing slag facilitate reduction of Tc(VII) to Tc(IV). These experiments differ from previous experiments where a 2% H{sub 2}(g) atmosphere was maintained (Kaplan et al., 2011 (SRNL-STI-2010-00668)). The impact of the 2% H{sub 2}(g) reducing atmosphere on this data was examined and determined to cause the reduction of Tc in experimental samples without slag. In the present ongoing study, after 56 days, Tc sorption by the 50-year old cement samples (no slag) was undetectable, whereas Tc sorption in the cementitious materials containing slag continues to increase with contact time (measured after 1, 4, 8, 19 and 56 days). Sorption was not consistent with spike concentrations and steady state has not been demonstrated after 56 days. The average conditional K{sub d} value for the Vault 2 cementitious material was 6,362 mL/g (17% slag), for the TR547 Saltstone (45% slag) the conditional K{sub d} was 1258 mL/g, and for TR545 (90% slag) the conditional K{sub d} was 12,112 mL/g. It is anticipated that additional samples will be collected until steady state

  20. Neuroleptics under high risk conditions.

    PubMed

    Oyewumi, L K

    1983-08-01

    A critical review of various high risk situations in which neuroleptics could be used and have been used in clinical practice is presented. These high risk situations include: women of child bearing age (pregnant women, lactating and/or nursing mothers), the two extremes of life (children and the elderly), patients with sexual dysfunction, patients with tardive dyskinesia, non-psychotic psychiatric patients, physically ill and suicidal patients. The extraordinary applications of these drugs, such as for rapid tranquilization and megadose regimens are examined. The author provides guidelines for the use of neuroleptics in these clinical situations.

  1. Reducing Heating In High-Speed Cinematography

    NASA Technical Reports Server (NTRS)

    Slater, Howard A.

    1989-01-01

    Infrared-absorbing and infrared-reflecting glass filters simple and effective means for reducing rise in temperature during high-speed motion-picture photography. "Hot-mirror" and "cold-mirror" configurations, employed in projection of images, helps prevent excessive heating of scenes by powerful lamps used in high-speed photography.

  2. Groundwater Oxidizing and Reducing Conditions Near Yucca Mountain

    NASA Astrophysics Data System (ADS)

    Al-Qudah, O. M.; Woocay, A.; Walton, J. C.

    2008-12-01

    Groundwater data from 73 wells in Yucca Mountain region were analyzed to better understand geochemical conditions and to make reducing/oxidizing (Redox) environment comparisons. Major ion chemistry, silica, fluoride and associated saturation indices, determined with PHREEQC, were sequentially examined using the multivariate statistical methods of principal component factor analysis and k means cluster analysis. Analysis of both major ion concentration data and their saturation indices allow simultaneous consideration of arithmetic (raw concentrations) and logarithmic (saturation indices) variables that describe the hydrochemical system and therefore can provide further insight into the system's behavior. The factor analysis of the major ion and saturation indices transforms the variables into a tractable number of descriptive factors that are rotated to summarize the chemical groundwater system and better interpret system variation. Results obtained from these analyses show a good agreement with literatures results. Literature indicates that the saturated zone (SZ) located to the east and south of the Yucca Mountain has reducing conditions, and oxidizing conditions are found elsewhere in the SZ flow system.

  3. Technetium Sorption by Cementitious Materials Under Reducing Conditions

    SciTech Connect

    Kaplan, Daniel I.; Estes, Shanna L.; Powell, Brian A.

    2012-09-28

    The objective of this study was to measure technetium ({sup 99}Tc) sorption to cementitious materials under reducing conditions to simulate Saltstone Disposal Facility conditions. {sup 99}Tc(VII) batch sorption experiments were conducted for 319 days in an inert glovebag with a variety of cementitious materials (aged cement, Vault 2, TR545, and TR547) containing varying amounts of blast furnace slag. Between 154 and 319 days, the {sup 99}Tc aqueous concentrations tended to remain constant and samples amended with different initial {sup 99}Tc concentrations, tended to merge at about 10{sup -9} M for Vault 2 (17% slag) and TR545 (90% slag) and 10{sup -8} M for TR547 (45% slag). This data provided strong evidence that solubility, and not adsorption (K{sub d} values), was controlling aqueous {sup 99}Tc concentrations. Laboratory data superimposed over thermodynamic speciation diagrams further supported the conclusion that solubility, and not adsorption controlled {sup 99}Tc aqueous concentrations. The oxidation state of the aqueous {sup 99}Tc at the end of the sorption experiment was determined by solvent extraction to be almost entirely {sup 99}Tc(VII). The pH of the present system was ~11.8. Previously proposed solubility controlling phases including Tc-sulfides may be present, but do not appear to control solubility. After the 319 day sorption period, the suspensions were removed from the glovebag and a desorption step under oxic conditions was conducted for 20 days by adding oxic, pH-buffered solutions to the suspensions. {sup 99}Tc aqueous concentrations increased by more than an order of magnitude and Eh increased by several hundred millivolts within 24 hours after the introduction of the oxic solutions. These desorption results are consistent with re-oxidation and dissolution/desorption of {sup 99}Tc(IV) phases possibly present in the cementitious materials after the anoxic sorption step of the experiment. Aqueous {sup 99}Tc concentrations continued to increase

  4. Technetium Sorption By Cementitious Materials Under Reducing Conditions

    SciTech Connect

    Kaplan, Daniel I.; Estes, Shanna L.; Arai, Yuji; Powell, Brian A.

    2013-07-18

    The objective of this study was to measure Tc sorption to cementitious materials under reducing conditions to simulate Saltstone Disposal Facility conditions. Earlier studies were conducted and the experimental conditions were found not to simulate those of the facility. Through a five month subcontract with Clemson University, sorption of {sup 99}Tc to four cementitious materials was examined within an anaerobic glovebag targeting a 0.1% H{sub 2}(g)/ 99.9% N{sub 2}(g) atmosphere. Early experiments based on Tc sorption and Eh indicated that 0.1% H{sub 2}(g) (a reductant) was necessary to preclude experimental impacts from O{sub 2}(g) diffusion into the glovebag. Preliminary data to date (up to 56 days) indicates that sorption of {sup 99}Tc to cementitious materials increased with increasing slag content for simulated saltstone samples. This is consistent with the conceptual model that redox active sulfide groups within the reducing slag facilitate reduction of Tc(VII) to Tc(IV). These experiments differ from previous experiments where a 2% H{sub 2}(g) atmosphere was maintained (Kaplan et al., 2011 (SRNL-STI-2010-00668)). The impact of the 2% H{sub 2}(g) reducing atmosphere on this data was examined and determined to cause the reduction of Tc in experimental samples without slag. In the present ongoing study, after 56 days, Tc sorption by the 50-year old cement samples (no slag) was undetectable, whereas Tc sorption in the cementitious materials containing slag continues to increase with contact time (measured after 1, 4, 8, 19 and 56 days). Sorption was not consistent with spike concentrations and steady state has not been demonstrated after 56 days. The average conditional K{sub d} value for the Vault 2 cementitious material was 873 mL/g (17% slag), for the TR547 Saltstone (45% slag) the conditional K{sub d} was 168 mL/g, and for TR545 (90% slag) the conditional K{sub d} was 1,619 mL/g. It is anticipated that additional samples will be collected until steady state

  5. Computational characterization of fracture healing under reduced gravity loading conditions.

    PubMed

    Gadomski, Benjamin C; Lerner, Zachary F; Browning, Raymond C; Easley, Jeremiah T; Palmer, Ross H; Puttlitz, Christian M

    2016-07-01

    The literature is deficient with regard to how the localized mechanical environment of skeletal tissue is altered during reduced gravitational loading and how these alterations affect fracture healing. Thus, a finite element model of the ovine hindlimb was created to characterize the local mechanical environment responsible for the inhibited fracture healing observed under experimental simulated hypogravity conditions. Following convergence and verification studies, hydrostatic pressure and strain within a diaphyseal fracture of the metatarsus were evaluated for models under both 1 and 0.25 g loading environments and compared to results of a related in vivo study. Results of the study suggest that reductions in hydrostatic pressure and strain of the healing fracture for animals exposed to reduced gravitational loading conditions contributed to an inhibited healing process, with animals exposed to the simulated hypogravity environment subsequently initiating an intramembranous bone formation process rather than the typical endochondral ossification healing process experienced by animals healing in a 1 g gravitational environment. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1206-1215, 2016.

  6. Reduced palatability in pain-induced conditioned taste aversions.

    PubMed

    Lin, Jian-You; Arthurs, Joe; Reilly, Steve

    2013-07-02

    The current study investigated whether internal pain-inducing agents can modulate palatability of a tastant in the same way as illness-inducing agents (e.g., lithium chloride). Similar to traditional conditioned taste aversion (CTA) experiments, during conditioning the rats were exposed to a saccharin solution followed by intraperitoneal injections of either gallamine (Experiment 1) or hypertonic sodium chloride (NaCl; Experiments 1 and 2). In addition to the total amount consumed, the time of each lick was recorded for lick pattern analysis. The results showed that both gallamine and hypertonic NaCl caused suppression in saccharin intake. Importantly, both lick cluster size and initial lick rate (the measures of taste palatability) were reduced as well. This pattern of results suggests that these pain-inducing agents reduce the hedonic value of the associated tastant and thus CTA is acquired. The current finding serves as evidence supporting the view that CTA is a broadly tuned mechanism that can be triggered by changes in internal body states following consummatory experience. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Anaerobic degradation of citrate under sulfate reducing and methanogenic conditions.

    PubMed

    Gámez, Victor M; Sierra-Alvarez, Reyes; Waltz, Rebecca J; Field, James A

    2009-07-01

    Citrate is an important component of metal processing effluents such as chemical mechanical planarization wastewaters of the semiconductor industry. Citrate can serve as an electron donor for sulfate reduction applied to promote the removal of metals, and it can also potentially be used by methanogens that coexist in anaerobic biofilms. The objective of this study was to evaluate the degradation of citrate with sulfate-reducing and methanogenic biofilms. During batch bioassays, the citrate, acetate, methane and sulfide concentrations were monitored. The results indicate that independent of the biofilm or incubation conditions used, citrate was rapidly fermented with specific rates ranging from 566 to 720 mg chemical oxygen demand (COD) consumed per gram volatile suspended solids per day. Acetate was found to be the main fermentation product of citrate degradation, which was later degraded completely under either methanogenic or sulfate reducing conditions. However, if either sulfate reduction or methanogenesis was infeasible due to specific inhibitors (2-bromoethane sulfonate), absence of sulfate or lack of adequate microorganisms in the biofilm, acetate accumulated to levels accounting for 90-100% of the citrate-COD consumed. Based on carbon balances measured in phosphate buffered bioassays, acetate, CO(2) and hydrogen are the main products of citrate fermentation, with a molar ratio of 2:2:1 per mol of citrate, respectively. In bicarbonate buffered bioassays, acetogenesis of H(2) and CO(2) increased the yield of acetate. The results taken as a whole suggest that in anaerobic biofilm systems, citrate is metabolized via the formation of acetate as the main metabolic intermediate prior to methanogenesis or sulfate reduction. Sulfate reducing consortia must be enriched to utilize acetate as an electron donor in order to utilize the majority of the electron-equivalents in citrate.

  8. Reducing the condition number for microlocal discretization problems.

    PubMed

    de La Bourdonnaye, Armel; Tolentino, Marc

    2004-03-15

    In this paper, we analyse the conditioning properties of systems arising from microlocal discretizations. These systems use oscillating basis functions to model wave problems in harmonic regime. Facing severe condition numbers, we first interpret the difficulty as coming from an over-discretization, which creates evanescent waves. The first solution we investigate is to project the problem onto the orthogonal of these modes. This is done on a model problem but it is not a satisfactory solution on real-sized systems. Then we propose to transform the linear system by using a wavelet basis. It appears that this transformation discriminates strongly between small and big matrix coefficients. This allows us to threshold the transformed system to obtain a reduced one which is both better conditioned and smaller. The use of wavelets is original, since the transformation is done in the spectral domain thanks to the microlocal discretization. We finally obtain a method that uses between one and two degrees of freedom by wavelength to simulate scattering problems.

  9. Legal Regulation of Sodium Consumption to Reduce Chronic Conditions.

    PubMed

    Hodge, James G; Barraza, Leila F

    2016-02-18

    In the United States, tens of thousands of Americans die each year of heart disease, stroke, or other chronic conditions tied to hypertension from long-term overconsumption of sodium compounds. Major strides to lower dietary sodium have been made over decades, but the goal of reducing Americans' daily consumption is elusive. The Food and Drug Administration (FDA) has been urged to consider stronger regulatory limits on sodium, especially in processed and prepared foods. Still, FDA categorizes salt (and many other sodium compounds) as "generally recognized as safe," meaning they can be added to foods when ingested in reasonable amounts. Legal reforms or actions at each level of government offer traditional and new routes to improving chronic disease outcomes. However, using law as a public health tool must be assessed carefully, given potential trade-offs and unproven efficacy.

  10. Reduced bleed air extraction for DC-10 cabin air conditioning

    NASA Technical Reports Server (NTRS)

    Newman, W. H.; Viele, M. R.; Hrach, F. J.

    1980-01-01

    It is noted that a significant fuel savings can be achieved by reducing bleed air used for cabin air conditioning. Air in the cabin can be recirculated to maintain comfortable ventilation rates but the quality of the air tends to decrease due to entrainment of smoke and odors. Attention is given to a development system designed and fabricated under the NASA Engine Component Improvement Program to define the recirculation limit for the DC-10. It is shown that with the system, a wide range of bleed air reductions and recirculation rates is possible. A goal of 0.8% fuel savings has been achieved which results from a 50% reduction in bleed extraction from the engine.

  11. Combustion of porous solids at reduced gravitational conditions

    NASA Technical Reports Server (NTRS)

    Berlad, A. L.; Killroy, J.

    1979-01-01

    A ground-based experimental and analytic study considered the utility and the feasibility of a space shuttle-based experimental study of the combustion poroussolids at reduced gravitational conditions. This ground-based study employed the Lewis Research Center's g = 0 (drop tower) facility. Experimental g = 1 studies were performed both at the Lewis Research Center and at State University of New York at Stony Brook. It is found that the considered space shuttle-based experimental program is expected to yield vital fundamental combustion information that is not obtainable from earth-bound studies alone. The considered space shuttle-based study is entirely feasible and a detailed approach to these experiments is presented.

  12. Legal Regulation of Sodium Consumption to Reduce Chronic Conditions

    PubMed Central

    Barraza, Leila F.

    2016-01-01

    In the United States, tens of thousands of Americans die each year of heart disease, stroke, or other chronic conditions tied to hypertension from long-term overconsumption of sodium compounds. Major strides to lower dietary sodium have been made over decades, but the goal of reducing Americans’ daily consumption is elusive. The Food and Drug Administration (FDA) has been urged to consider stronger regulatory limits on sodium, especially in processed and prepared foods. Still, FDA categorizes salt (and many other sodium compounds) as “generally recognized as safe,” meaning they can be added to foods when ingested in reasonable amounts. Legal reforms or actions at each level of government offer traditional and new routes to improving chronic disease outcomes. However, using law as a public health tool must be assessed carefully, given potential trade-offs and unproven efficacy. PMID:26890409

  13. Reduced bleed air extraction for DC-10 cabin air conditioning

    NASA Technical Reports Server (NTRS)

    Newman, W. H.; Viele, M. R.; Hrach, F. J.

    1980-01-01

    It is noted that a significant fuel savings can be achieved by reducing bleed air used for cabin air conditioning. Air in the cabin can be recirculated to maintain comfortable ventilation rates but the quality of the air tends to decrease due to entrainment of smoke and odors. Attention is given to a development system designed and fabricated under the NASA Engine Component Improvement Program to define the recirculation limit for the DC-10. It is shown that with the system, a wide range of bleed air reductions and recirculation rates is possible. A goal of 0.8% fuel savings has been achieved which results from a 50% reduction in bleed extraction from the engine.

  14. Release of Pharmaceuticals under Reducing Conditions in a Wastewater-Irrigated Mexican Soil.

    PubMed

    Dalkmann, Philipp; Dresemann, Tim-Fabian; Siebe, Christina; Mansfeldt, Tim; Amelung, Wulf; Siemens, Jan

    2014-11-01

    Wastewater irrigation is often performed by flood irrigation, leading to changes in redox potential (Eh) of irrigated soils. In addition to soil organic matter, Fe-(hydr)oxides are important sorbents for pollutants, and biotransformation of pollutants can be accelerated under reducing conditions. Here, the influence of reducing conditions on the release of sorbed pharmaceuticals from soil and their potential accelerated dissipation was investigated in a microcosm study. Samples of a soil from the Mezquital Valley (Mexico) irrigated for 85 yr with untreated wastewater were incubated under oxidizing (Eh of 500 ± 20 mV), weakly reducing (Eh of 100 ± 20 mV), and moderately reducing (Eh of -100 ± 20 mV) soil conditions for 30 to 31 d. The concentrations of nine pharmaceuticals (bezafibrate, carbamazepine, ciprofloxacin, sulfamethoxazole, trimethoprim, enrofloxacin, clarithromycin, diclofenac, and naproxen) were extracted via solid-phase extraction from soil slurries and analyzed by liquid chromatography-tandem mass spectrometry. Low Eh did not lead to a release of formerly sorbed pharmaceuticals from the wastewater irrigated soil. High pH values (>8) of the examined soil resulting from denitrification under reducing conditions prevented the dissolution of Fe-(hydr)oxides and, hence, the potential release of pharmaceuticals. A trend of decreasing concentrations of sulfamethoxazole and bezafibrate with time under moderately reducing conditions supports previous findings of a transformation of these compounds under anaerobic conditions.

  15. Transformation of nitroaromatic pesticides under sulfate-reducing condition (SRC)

    SciTech Connect

    Gui, L.; Bouwer, E.J.

    1996-10-01

    Nitroaromatic pesticides are widely used and have been detected in various environments. Little is known about their fate under SRC where H{sub 2}S levels are elevated due to microbial activity. Nitroaromatics are highly susceptible to biotic and abiotic transformation under SRC. The objectives of this research were to evaluate the importance of biotic and abiotic transformation processes and to determine factors affecting transformation rates under SRC. Trifluralin, dicloran, PCNB, and dinoseb were examined. Biotic and abiotic transformation of PCNB and trifluralin occurred rapidly, while dicloran could only be biotically transformed. Dinoseb transformation was affected by bacterial growth conditions (the presence of co-substrates and yeast extract) for biotic transformation and the availability of H{sub 2}S and trace metals for abiotic transformation. Trace metals served as electron mediators. All pesticide transformations followed pseudo-first order kinetics. The initial transformation step appeared to be nitroreduction. This information provides ways to manipulate environmental conditions to enhance anaerobic remediation of nitroaromatic pesticides.

  16. Chalcophile element partitioning in highly oxidised and highly reduced bodies.

    NASA Astrophysics Data System (ADS)

    Kiseeva, K.; Wood, B. J.

    2015-12-01

    In our recent studies [1-3] we showed that partitioning of many chalcophile elements could be described by a simple relationship as a function of the FeO content of the silicate liquid. LogDi ~= A-0.5nlog[FeO] where A is a constant, n is the constant related to the valency of element i and [FeO] is the concentration of FeO in the silicate melt. For many chalcophile and moderately chalcophile elements (e.g., Zn, Cr, Pb, Sb, In), the fitted slope n depends only on the valency of the element. More lithophile elements (e.g., Ti, Nb, Ce, Ga) exhibit concave upwards behavior on a plot of logD versus log[FeO] due to their strong interaction with oxygen in sulphide, which increases with the increasing FeO content of the silicate liquid. Strongly chalcophile elements, like Cu, Ag and Ni have the opposite trend (concave downwards) and their D decreases both at high (> 10-12wt %) and very low (< 1wt%) FeO contents of the silicate melt. These changes correlate with increasing S content of the silicate melt (up to 11 wt%) as the FeO content of the silicate melt declines to ~0.3wt%. An experiment at 1.5 GPa/1420oC having 4 wt% S and 0.28 wt% FeO in the silicate melt has DCu (sulf/sil) ~ 84, which is about 6 times lower than the DCu(sulf/sil) at identical p-T conditions but at 8 wt% FeO in the silicate melt. Our new experimental data on Re partitioning between sulphide and silicate melt in the CMAS+FeO system show that Re behaves similarly to the highly chalcophile elements and exhibits concave downwards behaviour on the LogD/LogFeO diagram. With the highest DRe (sulf/sil) at around 1.5-2.0x104 at 1.5-6.0 wt% FeO in the silicate melt, DRe (sulf/sil) declines to the values of 50-150 at ~0.5 wt% and > ~15 wt% FeO in the silicate melt, respectively. This means that at highly reducing conditions Re is similarly or less chalcophile than some of the highly lithophile elements, like Ta (D ≈ 9), Nb (D ≈ 600), Ti (D ≈ 6) [3]. The results mean that in oxidised bodies like Mars and

  17. Bacterial siderophores promote dissolution of UO2 under reducing conditions.

    PubMed

    Frazier, Scott W; Kretzschmar, Ruben; Kraemer, Stephan M

    2005-08-01

    Tetravalent actinides are often considered environmentally immobile due to their strong hydrolysis and formation of sparingly soluble oxide phases. However, biogenic ligands commonly found in the soil environment may increase their solubility and mobility. We studied the adsorption and dissolution kinetics of UO2 in the presence of a microbial siderophore, desferrioxamine-B (DFO-B), under reducing conditions. Using batch and continuous flow stirred tank reactors (CFSTR),we found that DFO-B increases the solubility of UIV and accelerates UO2 dissolution rates through a ligand-promoted dissolution mechanism. DFO-B adsorption to UO2 followed a Langmuir-type isotherm. The maximum adsorbed DFO-B concentrations were 3.3 micromol m(-2) between pH 3 and 8 and declined above pH 8. DFO-B dissolved UO2 at a DFO-B surface-saturated net rate of 64 nmol h(-1) m(-2) (pH 7.5, l = 0.01 M) according to the first-order rate equation R = kL[Lads], with a rate coefficient kL of 0.019 h(-1). Even at very low siderophore concentrations (e.g. 1 microM), net dissolution rates (16 nmol h(-1) m(-2), pH 7.5, l = 0.01 M) were substantially greater than net proton-promoted dissolution rates (3 nmol h(-1) m(-2), pH 7-7.5, l = 0.01 M). Interestingly, adding dissolved FeIII had negligible effects on DFO-B-promoted UO2 dissolution rates, despite its potential as a competitor for DFO-B and as an oxidant of UIV. Our results suggest that strong organic ligands could influence the environmental mobility of tetravalent actinides and should be considered in predictions for nuclear waste storage and remediation strategies.

  18. Reducing stigma in high school youth.

    PubMed

    Koller, M; Stuart, H

    2016-08-01

    We evaluated 21 contact-based education interventions in 5047 Canadian high school students and identified student characteristics associated with success. We used a one-group pretest/posttest design with standardized instruments to measure changes in behavioural intent. Variability across interventions was assessed using meta-analysis, and a mixed-effects logistic regression was used to identify student characteristics. Interventions were heterogeneous (I(2)  = 62.4%) but generally successful. The odds of getting an A grade was 2.57 times greater on the posttest than the pretest (95% CI = 2.18, 3.03). Males were less likely to achieve a passing score overall; however, males who self-disclosed a mental illness were more likely to pass. Three percent of students experienced a large drop in social acceptance following the intervention. These were more likely to be male [OR = 1.5 (95% CI = 1.0, 2.1)]. Contact-based education is a promising practice for reducing stigma in high school students, although the field would benefit from fidelity criteria to reduce variation across interventions. Males and females react differently to antistigma programming; particularly those with self-reported mental illnesses and a small proportion may become more intolerant. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Effects of reservoir anaerobic, reducing conditions on surfactant retention in chemical flooding

    SciTech Connect

    Wang, F.H.L. )

    1993-05-01

    Surfactant retentions observed in four microemulsion-flooding pilot tests at the Loudon field were substantially lower than predicted from conventional laboratory coreflood experiments. This paper presents research results that explain this discrepancy. The oil reservoir was in an anaerobic, reducing conditions, whereas laboratory corefloods were normally conducted under aerobic, oxidizing conditions. The difference in redox condition was shown to have a serious effect on surfactant retention. Laboratory corefloods conducted under reservoir-like, anaerobic, reducing conditions gave surfactant retention results significantly closer to those observed in field tests. The effect of redox conditions on surfactant adsorption was substantiated further by results from static adsorption experiments with various clay types. Exposure of preserved cores from a reduced reservoir to aerobic conditions can cause high surfactant retention in corefloods. Methods were developed to restore such oxygen-contaminated core material to its original, anaerobic, reduced state. These coreflood procedures simulate actual reservoir conditions better and give meaningful surfactant-retention results for process design optimization.

  20. In situ mobility of uranium in the presence of nitrate following sulfate-reducing conditions

    DOE PAGES

    Paradis, Charles J.; Jagadamma, Sindhu; Watson, David B.; ...

    2016-02-11

    Reoxidation and mobilization of previously reduced and immobilized uranium by dissolved phase oxidants poses a significant challenge for remediating uranium-contaminated groundwater. Preferential oxidation of reduced sulfur-bearing species, as opposed to reduced uranium bearing species, has been demonstrated to limit the mobility of uranium at the laboratory scale yet field-scale investigations are lacking. Here in this study, the mobility of uranium in the presence of nitrate oxidant was investigated in a shallow groundwater system after establishing conditions conducive to uranium reduction and the formation of reduced sulfur-bearing species. A series of three injections of groundwater (200 L) containing U(VI) (5 μM)more » and amended with ethanol (40 mM) and sulfate (20 mM) were conducted in ten test wells in order to stimulate microbial mediated reduction of uranium and the formation of reduced sulfur-bearing species. Simultaneous push-pull tests were then conducted in triplicate well clusters to investigate the mobility of U(VI) under three conditions: 1) high nitrate (120 mM), 2) high nitrate (120 mM) with ethanol (30 mM), and 3) low nitrate (2 mM) with ethanol (30 mM). Dilution-adjusted breakthrough curves of ethanol, nitrate, nitrite, sulfate, and U(VI) suggested that nitrate reduction was predominantly coupled to the oxidation of reduced-sulfur bearing species, as opposed to the reoxidation of U(IV), under all three conditions for the duration of the 36-day tests. The amount of sulfate, but not U(VI), recovered during the push-pull tests was substantially more than injected, relative to bromide tracer, under all three conditions and further suggested that reduced sulfur-bearing species were preferentially oxidized under nitrate-reducing conditions. However, some reoxidation of U(IV) was observed under nitrate-reducing conditions and in the absence of detectable nitrate and/or nitrite. This suggested that reduced sulfur-bearing species may not be fully

  1. In situ mobility of uranium in the presence of nitrate following sulfate-reducing conditions

    NASA Astrophysics Data System (ADS)

    Paradis, Charles J.; Jagadamma, Sindhu; Watson, David B.; McKay, Larry D.; Hazen, Terry C.; Park, Melora; Istok, Jonathan D.

    2016-04-01

    Reoxidation and mobilization of previously reduced and immobilized uranium by dissolved-phase oxidants poses a significant challenge for remediating uranium-contaminated groundwater. Preferential oxidation of reduced sulfur-bearing species, as opposed to reduced uranium-bearing species, has been demonstrated to limit the mobility of uranium at the laboratory scale yet field-scale investigations are lacking. In this study, the mobility of uranium in the presence of nitrate oxidant was investigated in a shallow groundwater system after establishing conditions conducive to uranium reduction and the formation of reduced sulfur-bearing species. A series of three injections of groundwater (200 L) containing U(VI) (5 μM) and amended with ethanol (40 mM) and sulfate (20 mM) were conducted in ten test wells in order to stimulate microbial-mediated reduction of uranium and the formation of reduced sulfur-bearing species. Simultaneous push-pull tests were then conducted in triplicate well clusters to investigate the mobility of U(VI) under three conditions: 1) high nitrate (120 mM), 2) high nitrate (120 mM) with ethanol (30 mM), and 3) low nitrate (2 mM) with ethanol (30 mM). Dilution-adjusted breakthrough curves of ethanol, nitrate, nitrite, sulfate, and U(VI) suggested that nitrate reduction was predominantly coupled to the oxidation of reduced-sulfur bearing species, as opposed to the reoxidation of U(IV), under all three conditions for the duration of the 36-day tests. The amount of sulfate, but not U(VI), recovered during the push-pull tests was substantially more than injected, relative to bromide tracer, under all three conditions and further suggested that reduced sulfur-bearing species were preferentially oxidized under nitrate-reducing conditions. However, some reoxidation of U(IV) was observed under nitrate-reducing conditions and in the absence of detectable nitrate and/or nitrite. This suggested that reduced sulfur-bearing species may not be fully effective at

  2. In situ mobility of uranium in the presence of nitrate following sulfate-reducing conditions.

    PubMed

    Paradis, Charles J; Jagadamma, Sindhu; Watson, David B; McKay, Larry D; Hazen, Terry C; Park, Melora; Istok, Jonathan D

    2016-04-01

    Reoxidation and mobilization of previously reduced and immobilized uranium by dissolved-phase oxidants poses a significant challenge for remediating uranium-contaminated groundwater. Preferential oxidation of reduced sulfur-bearing species, as opposed to reduced uranium-bearing species, has been demonstrated to limit the mobility of uranium at the laboratory scale yet field-scale investigations are lacking. In this study, the mobility of uranium in the presence of nitrate oxidant was investigated in a shallow groundwater system after establishing conditions conducive to uranium reduction and the formation of reduced sulfur-bearing species. A series of three injections of groundwater (200 L) containing U(VI) (5 μM) and amended with ethanol (40 mM) and sulfate (20 mM) were conducted in ten test wells in order to stimulate microbial-mediated reduction of uranium and the formation of reduced sulfur-bearing species. Simultaneous push-pull tests were then conducted in triplicate well clusters to investigate the mobility of U(VI) under three conditions: 1) high nitrate (120 mM), 2) high nitrate (120 mM) with ethanol (30 mM), and 3) low nitrate (2 mM) with ethanol (30 mM). Dilution-adjusted breakthrough curves of ethanol, nitrate, nitrite, sulfate, and U(VI) suggested that nitrate reduction was predominantly coupled to the oxidation of reduced-sulfur bearing species, as opposed to the reoxidation of U(IV), under all three conditions for the duration of the 36-day tests. The amount of sulfate, but not U(VI), recovered during the push-pull tests was substantially more than injected, relative to bromide tracer, under all three conditions and further suggested that reduced sulfur-bearing species were preferentially oxidized under nitrate-reducing conditions. However, some reoxidation of U(IV) was observed under nitrate-reducing conditions and in the absence of detectable nitrate and/or nitrite. This suggested that reduced sulfur-bearing species may not be fully effective at

  3. On High-Order Radiation Boundary Conditions

    NASA Technical Reports Server (NTRS)

    Hagstrom, Thomas

    1995-01-01

    In this paper we develop the theory of high-order radiation boundary conditions for wave propagation problems. In particular, we study the convergence of sequences of time-local approximate conditions to the exact boundary condition, and subsequently estimate the error in the solutions obtained using these approximations. We show that for finite times the Pade approximants proposed by Engquist and Majda lead to exponential convergence if the solution is smooth, but that good long-time error estimates cannot hold for spatially local conditions. Applications in fluid dynamics are also discussed.

  4. Successful pregnancy and childbirth after reduced intensity conditioning and partially HLA-mismatched bone marrow transplantation

    PubMed Central

    Fuchs, Ephraim J.; Luznik, Leo; Bolaños-Meade, Javier; Miller, Carole B.; Brodsky, Robert A.; Ambinder, Richard F.; Jones, Richard J.

    2011-01-01

    Ovarian failure and permanent infertility occur in nearly all women of childbearing age who are treated with myeloablative conditioning and allogeneic stem cell transplantation (SCT).1,2 Recently, highly immunosuppressive but reduced intensity conditioning regimens have enabled the engraftment of allogeneic cells and their resulting graft-versus-tumor effects.3–5 However, the effect of reduced intensity allogeneic stem cell transplantation, or RIST, on the reproductive function of young women has not been examined. Here we report on two women who had successful pregnancies and childbirths after RIST for lymphoma. PMID:19139737

  5. Growth Conditions To Reduce Oxalic Acid Content of Spinach

    NASA Technical Reports Server (NTRS)

    Johnson-Rutzke, Corinne

    2003-01-01

    A controlled-environment agricultural (CEA) technique to increase the nutritive value of spinach has been developed. This technique makes it possible to reduce the concentration of oxalic acid in spinach leaves. It is desirable to reduce the oxalic acid content because oxalic acid acts as an anti-nutritive calcium-binding component. More than 30 years ago, an enzyme (an oxidase) that breaks down oxalic acid into CO2 and H2O2 was discovered and found to be naturally present in spinach leaves. However, nitrate, which can also be present because of the use of common nitratebased fertilizers, inactivates the enzyme. In the CEA technique, one cuts off the supply of nitrate and keeps the spinach plants cool while providing sufficient oxygen. This technique provides the precise environment that enables the enzyme to naturally break down oxalate. The result of application of this technique is that the oxalate content is reduced by 2/3 in one week.

  6. Fatal immune-mediated pancytopenia and a TRALI-like syndrome associated with high titers of recipient-type antibodies against donor-derived peripheral blood cells after allogeneic bone marrow transplantation following dose reduced conditioning.

    PubMed

    Knop, Stefan; Bux, Juergen; Kroeber, Stefan M; Bader, Peter; Hebart, Holger; Kanz, Lothar; Einsele, Hermann

    2004-05-01

    Pancytopenia occurring after bone marrow transplantation is a rare complication. A 47 year old patient with progression of multiple myeloma after standard therapy received an allogeneic marrow graft from a matched unrelated donor. The non-myeloablative conditioning regimen consisted of fludarabine, cyclophosphamide, rabbit anti-thymocyte globulin and total body irradiation. GVHD prophylaxis consisted of cyclosporine. Neutrophil engraftment was as expected and the patient was discharged without signs of acute GvHD. On day +34 the patient presented with clinical and laboratory findings consistent with severe pancytopenia. Antibodies against red cells, platelets, lymphocytes and granulocytes were detected in extremely high titers. Immune-mediated pancytopenia was refractory on multiple immunosuppressive treatment strategies. Proliferation of polyclonal plasma cells of recipient-type that was documented postmortem, was most likely responsible for excessive antibody formation.

  7. Reduced amygdala activity during aversive conditioning in human narcolepsy.

    PubMed

    Ponz, Aurélie; Khatami, Ramin; Poryazova, Rositsa; Werth, Esther; Boesiger, Peter; Schwartz, Sophie; Bassetti, Claudio L

    2010-03-01

    Narcolepsy with cataplexy is a sleep-wake disorder caused by a loss of hypothalamic hypocretins. Here we assessed the time course of amygdala activation during aversive conditioning in unmedicated patients with narcolepsy. Unlike healthy matched control subjects, narcolepsy patients had no enhancement of amygdala response to conditioned stimuli and no increase in functional coupling between the amygdala and medial prefrontal cortex. These findings suggest that human narcolepsy is accompanied by abnormal emotional learning, and that, in line with animal data, the hypocretin system and the amygdala are involved in this process.

  8. Nasal high flow reduces dead space.

    PubMed

    Möller, Winfried; Feng, Sheng; Domanski, Ulrike; Franke, Karl-Josef; Celik, Gülnaz; Bartenstein, Peter; Becker, Sven; Meyer, Gabriele; Schmid, Otmar; Eickelberg, Oliver; Tatkov, Stanislav; Nilius, Georg

    2017-01-01

    Recent studies show that nasal high flow (NHF) therapy can support ventilation in patients with acute or chronic respiratory disorders. Clearance of dead space has been suggested as being the key mechanism of respiratory support with NHF therapy. The hypothesis of this study was that NHF in a dose-dependent manner can clear dead space of the upper airways from expired air and decrease rebreathing. The randomized crossover study involved 10 volunteers using scintigraphy with (81m)Krypton ((81m)Kr) gas during a breath-holding maneuver with closed mouth and in 3 nasally breathing tracheotomized patients by volumetric capnography and oximetry through sampling CO2 and O2 in the trachea and measuring the inspired volume with inductance plethysmography following NHF rates of 15, 30, and 45 l/min. The scintigraphy revealed a decrease in (81m)Kr gas clearance half-time with an increase of NHF in the nasal cavities [Pearson's correlation coefficient cc = -0.55, P < 0.01], the pharynx (cc = -0.41, P < 0.01), and the trachea (cc = -0.51, P < 0.01). Clearance rates in nasal cavities derived from time constants and MRI-measured volumes were 40.6 ± 12.3 (SD), 52.5 ± 17.7, and 72.9 ± 21.3 ml/s during NHF (15, 30, and 45 l/min, respectively). Measurement of inspired gases in the trachea showed an NHF-dependent decrease of inspired CO2 that correlated with an increase of inspired O2 (cc = -0.77, P < 0.05). NHF clears the upper airways of expired air, which reduces dead space by a decrease of rebreathing making ventilation more efficient. The dead space clearance is flow and time dependent, and it may extend below the soft palate.

  9. Nasal high flow reduces dead space

    PubMed Central

    Feng, Sheng; Domanski, Ulrike; Franke, Karl-Josef; Celik, Gülnaz; Bartenstein, Peter; Becker, Sven; Meyer, Gabriele; Schmid, Otmar; Eickelberg, Oliver; Tatkov, Stanislav; Nilius, Georg

    2017-01-01

    Recent studies show that nasal high flow (NHF) therapy can support ventilation in patients with acute or chronic respiratory disorders. Clearance of dead space has been suggested as being the key mechanism of respiratory support with NHF therapy. The hypothesis of this study was that NHF in a dose-dependent manner can clear dead space of the upper airways from expired air and decrease rebreathing. The randomized crossover study involved 10 volunteers using scintigraphy with 81mKrypton (81mKr) gas during a breath-holding maneuver with closed mouth and in 3 nasally breathing tracheotomized patients by volumetric capnography and oximetry through sampling CO2 and O2 in the trachea and measuring the inspired volume with inductance plethysmography following NHF rates of 15, 30, and 45 l/min. The scintigraphy revealed a decrease in 81mKr gas clearance half-time with an increase of NHF in the nasal cavities [Pearson’s correlation coefficient cc = −0.55, P < 0.01], the pharynx (cc = −0.41, P < 0.01), and the trachea (cc = −0.51, P < 0.01). Clearance rates in nasal cavities derived from time constants and MRI-measured volumes were 40.6 ± 12.3 (SD), 52.5 ± 17.7, and 72.9 ± 21.3 ml/s during NHF (15, 30, and 45 l/min, respectively). Measurement of inspired gases in the trachea showed an NHF-dependent decrease of inspired CO2 that correlated with an increase of inspired O2 (cc = −0.77, P < 0.05). NHF clears the upper airways of expired air, which reduces dead space by a decrease of rebreathing making ventilation more efficient. The dead space clearance is flow and time dependent, and it may extend below the soft palate. NEW & NOTEWORTHY Clearance of expired air in upper airways by nasal high flow (NHF) can be extended below the soft palate and de facto causes a reduction of dead space. Using scintigraphy, the authors found a relationship between NHF, time, and clearance. Direct measurement of CO2 and O2 in the trachea confirmed a reduction of rebreathing, providing

  10. Lincoln Laboratory demonstrates highly accurate vehicle localization under adverseweather conditions

    DTIC Science & Technology

    2016-06-24

    rely on optics to ‘see’ lane markings, road surface maps, and surrounding infrastructure to orient themselves. Optical systems work well in fair ...in fair weather conditions. The use of a subsurface map reduces the need for continual modifications to high-resolution road maps. Fusing GPS, lidar

  11. Nucleate Boiling Heat Transfer Studied Under Reduced-Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Chao, David F.; Hasan, Mohammad M.

    2000-01-01

    Boiling is known to be a very efficient mode of heat transfer, and as such, it is employed in component cooling and in various energy-conversion systems. In space, boiling heat transfer may be used in thermal management, fluid handling and control, power systems, and on-orbit storage and supply systems for cryogenic propellants and life-support fluids. Recent interest in the exploration of Mars and other planets and in the concept of in situ resource utilization on the Martian and Lunar surfaces highlights the need to understand how gravity levels varying from the Earth's gravity to microgravity (1g = or > g/g(sub e) = or > 10(exp -6)g) affect boiling heat transfer. Because of the complex nature of the boiling process, no generalized prediction or procedure has been developed to describe the boiling heat transfer coefficient, particularly at reduced gravity levels. Recently, Professor Vijay K. Dhir of the University of California at Los Angeles proposed a novel building-block approach to investigate the boiling phenomena in low-gravity to microgravity environments. This approach experimentally investigates the complete process of bubble inception, growth, and departure for single bubbles formed at a well-defined and controllable nucleation site. Principal investigator Professor Vijay K. Dhir, with support from researchers from the NASA Glenn Research Center at Lewis Field, is performing a series of pool boiling experiments in the low-gravity environments of the KC 135 microgravity aircraft s parabolic flight to investigate the inception, growth, departure, and merger of bubbles from single- and multiple-nucleation sites as a function of the wall superheat and the liquid subcooling. Silicon wafers with single and multiple cavities of known characteristics are being used as test surfaces. Water and PF5060 (an inert liquid) were chosen as test liquids so that the role of surface wettability and the magnitude of the effect of interfacial tension on boiling in reduced

  12. A strategy for oxygen conditioning at high altitude: comparison with air conditioning.

    PubMed

    West, John B

    2015-09-15

    Large numbers of people live or work at high altitude, and many visit to trek or ski. The inevitable hypoxia impairs physical working capacity, and at higher altitudes there is also cognitive impairment. Twenty years ago oxygen enrichment of room air was introduced to reduce the hypoxia, and this is now used in dormitories, hotels, mines, and telescopes. However, recent advances in technology now allow large amounts of oxygen to be obtained from air or cryogenic oxygen sources. As a result it is now feasible to oxygenate large buildings and even institutions such as hospitals. An analogy can be drawn between air conditioning that has improved the living and working conditions of millions of people who live in hot climates and oxygen conditioning that can do the same at high altitude. Oxygen conditioning is similar to air conditioning except that instead of cooling the air, the oxygen concentration is raised, thus reducing the equivalent altitude. Oxygen conditioning on a large scale could transform living and working conditions at high altitude, where it could be valuable in homes, hospitals, schools, dormitories, company headquarters, banks, and legislative settings.

  13. Human Locomotion under Reduced Gravity Conditions: Biomechanical and Neurophysiological Considerations

    PubMed Central

    Sylos-Labini, Francesca; Ivanenko, Yuri P.

    2014-01-01

    Reduced gravity offers unique opportunities to study motor behavior. This paper aims at providing a review on current issues of the known tools and techniques used for hypogravity simulation and their effects on human locomotion. Walking and running rely on the limb oscillatory mechanics, and one way to change its dynamic properties is to modify the level of gravity. Gravity has a strong effect on the optimal rate of limb oscillations, optimal walking speed, and muscle activity patterns, and gait transitions occur smoothly and at slower speeds at lower gravity levels. Altered center of mass movements and interplay between stance and swing leg dynamics may challenge new forms of locomotion in a heterogravity environment. Furthermore, observations in the lack of gravity effects help to reveal the intrinsic properties of locomotor pattern generators and make evident facilitation of nonvoluntary limb stepping. In view of that, space neurosciences research has participated in the development of new technologies that can be used as an effective tool for gait rehabilitation. PMID:25247179

  14. Human locomotion under reduced gravity conditions: biomechanical and neurophysiological considerations.

    PubMed

    Sylos-Labini, Francesca; Lacquaniti, Francesco; Ivanenko, Yuri P

    2014-01-01

    Reduced gravity offers unique opportunities to study motor behavior. This paper aims at providing a review on current issues of the known tools and techniques used for hypogravity simulation and their effects on human locomotion. Walking and running rely on the limb oscillatory mechanics, and one way to change its dynamic properties is to modify the level of gravity. Gravity has a strong effect on the optimal rate of limb oscillations, optimal walking speed, and muscle activity patterns, and gait transitions occur smoothly and at slower speeds at lower gravity levels. Altered center of mass movements and interplay between stance and swing leg dynamics may challenge new forms of locomotion in a heterogravity environment. Furthermore, observations in the lack of gravity effects help to reveal the intrinsic properties of locomotor pattern generators and make evident facilitation of nonvoluntary limb stepping. In view of that, space neurosciences research has participated in the development of new technologies that can be used as an effective tool for gait rehabilitation.

  15. Characteristics of blast furnace slag leachate produced under reduced and oxidized conditions.

    PubMed

    Schwab, A P; Hickey, J; Hunter, J; Banks, M K

    2006-01-01

    A laboratory study was conducted to determine the environmental conditions necessary to reproduce leachates observed emerging from blast furnace slag acting as the foundation of highways in northwest Indiana. The leachates in the field are often highly alkaline with a pungent sulfur odor, a distinct green or milky-white in color, and sulfate concentrations exceeding 2,000 mg/L. Slag was equilibrated in the laboratory under both oxidized and anoxic environments and at various slag:water ratios. Constant anoxic conditions were required to produce to green colors in the slag, but high sulfate concentrations were observed only when the suspensions were fully oxidized. Leachate from the study site appears to form as a result of a series of complex chemical reactions including fluctuating oxidized and reduced conditions.

  16. Plutonium Oxidation State Distribution under Aerobic and Anaerobic Subsurface Conditions for Metal-Reducing Bacteria

    NASA Astrophysics Data System (ADS)

    Reed, D. T.; Swanson, J.; Khaing, H.; Deo, R.; Rittmann, B.

    2009-12-01

    The fate and potential mobility of plutonium in the subsurface is receiving increased attention as the DOE looks to cleanup the many legacy nuclear waste sites and associated subsurface contamination. Plutonium is the near-surface contaminant of concern at several DOE sites and continues to be the contaminant of concern for the permanent disposal of nuclear waste. The mobility of plutonium is highly dependent on its redox distribution at its contamination source and along its potential migration pathways. This redox distribution is often controlled, especially in the near-surface where organic/inorganic contaminants often coexist, by the direct and indirect effects of microbial activity. The redox distribution of plutonium in the presence of facultative metal reducing bacteria (specifically Shewanella and Geobacter species) was established in a concurrent experimental and modeling study under aerobic and anaerobic conditions. Pu(VI), although relatively soluble under oxidizing conditions at near-neutral pH, does not persist under a wide range of the oxic and anoxic conditions investigated in microbiologically active systems. Pu(V) complexes, which exhibit high chemical toxicity towards microorganisms, are relatively stable under oxic conditions but are reduced by metal reducing bacteria under anaerobic conditions. These facultative metal-reducing bacteria led to the rapid reduction of higher valent plutonium to form Pu(III/IV) species depending on nature of the starting plutonium species and chelating agents present in solution. Redox cycling of these lower oxidation states is likely a critical step in the formation of pseudo colloids that may lead to long-range subsurface transport. The CCBATCH biogeochemical model is used to explain the redox mechanisms and final speciation of the plutonium oxidation state distributions observed. These results for microbiologically active systems are interpreted in the context of their importance in defining the overall migration

  17. Physiological responses to ocean acidification and warming synergistically reduce condition of the common cockle Cerastoderma edule.

    PubMed

    Ong, E Z; Briffa, M; Moens, T; Van Colen, C

    2017-09-01

    The combined effect of ocean acidification and warming on the common cockle Cerastoderma edule was investigated in a fully crossed laboratory experiment. Survival of the examined adult organisms remained high and was not affected by elevated temperature (+3 °C) or lowered pH (-0.3 units). However, the morphometric condition index of the cockles incubated under high pCO2 conditions (i.e. combined warming and acidification) was significantly reduced after six weeks of incubation. Respiration rates increased significantly under low pH, with highest rates measured under combined warm and low pH conditions. Calcification decreased significantly under low pH while clearance rates increased significantly under warm conditions and were generally lower in low pH treatments. The observed physiological responses suggest that the reduced food intake under hypercapnia is insufficient to support the higher energy requirements to compensate for the higher costs for basal maintenance and growth in future high pCO2 waters. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Environmental Factors Affecting Ammonium Oxidation Under Iron Reducing Conditions

    NASA Astrophysics Data System (ADS)

    Jaffe, P. R.; Huang, S.; Ruiz-Urigüen, M.

    2014-12-01

    Ammonium (NH4+) oxidation coupled to iron (Fe) reduction in the absence of oxygen and nitrate/nitrite (NO3-/NO2-) has been reported by several investigators and referred to as Feammox. Feammox is a biological reaction, where Fe(III) is the electron acceptor, which is reduced to Fe(II), and NH4+ is the electron donor, which is oxidized to NO2-. Through a 180-day anaerobic incubation experiment, and using PCR-DGGE, 454-pyosequecing and qPCR analysis, we have shown that an Acidimicrobiaceae bacterium A6, a previously unreported species in the Acidimicrobiaceae family, might be either responsible or plays a key role in the Feammox process, We have enriched these Feammox bacteria (65.8% in terms of cell numbers) in a membrane reactor, and isolated the pure Acidimicrobiaceae bacterium A6 strain in an autotrophic medium. In samples collected and then incubated from a series of local wetland-, upland-, as well as storm-water detention pond-sediments, Feammox activity was only detected in acidic soil environments that contain Fe oxides. Using primers we developed for this purpose, Acidimicrobiaceae bacterium A6 was detected in all incubations where Feammox was observed. Anaerobic incubations of Feammox enrichment cultures adjusted to different pH, revealed that the optimal pH for Feammox is 4 ~ 5, and the reaction does not proceed when pH > 7. Feammox was still proceeding at pH as low as 2. In Feammox culture amended with different Fe(III) sources, Feammox reaction proceeded only when Fe oxides (ferrihydrite or goethite ) were supplied, whereas samples incubated with ferric chloride or ferric citrate showed no measurable NH4+ oxidation. Furthermore, we have also determined from incubation experiments conducted with a temperature gradient (10 ~ 35℃), that the Feammox process was active when the temperature is above 15℃, and the optimal temperature is 20℃. Incubations of enrichment culture with 79% Feammox bacteria appeared to remove circa 8% more NH4+ at 20ºC than at

  19. Quality indicators for high acuity pediatric conditions.

    PubMed

    Stang, Antonia S; Straus, Sharon E; Crotts, Jennifer; Johnson, David W; Guttmann, Astrid

    2013-10-01

    Identifying gaps in care and improving outcomes for severely ill children requires the development of evidence-based performance measures. We used a systematic process involving multiple stakeholders to identify and develop evidence-based quality indicators for high acuity pediatric conditions relevant to any emergency department (ED) setting where children are seen. A prioritized list of clinical conditions was selected by an advisory panel. A systematic review of the literature was conducted to identify existing indicators, as well as guidelines and evidence that could be used to inform the creation of new indicators. A multiphase, Rand-modified Delphi method consisting of anonymous questionnaires and a face-to-face meeting of an expert panel was used for indicator selection. Measure specifications and evidence grading were created for each indicator, and the feasibility and reliability of measurement was assessed in a tertiary care pediatric ED. The conditions selected for indicator development were diabetic ketoacidosis, status asthmaticus, anaphylaxis, status epilepticus, severe head injury, and sepsis. The majority of the 62 selected indicators reflect ED processes (84%) with few indicators reflecting structures (11%) or outcomes (5%). Thirty-seven percent (n = 23) of the selected indicators are based on moderate or high quality evidence. Data were available and interrater reliability acceptable for the majority of indicators. A systematic process involving multiple stakeholders was used to develop evidence-based quality indicators for high acuity pediatric conditions. Future work will test the reliability and feasibility of data collection on these indicators across the spectrum of ED settings that provide care for children.

  20. Highly Challenging Balance Program Reduces Fall Rate in Parkinson Disease

    PubMed Central

    Sparrow, David; DeAngelis, Tamara R.; Hendron, Kathryn; Thomas, Cathi A.; Saint-Hilaire, Marie; Ellis, Terry

    2015-01-01

    Background and Purpose There is a paucity of effective treatment options to reduce falls in Parkinson’s disease (PD). Although a variety of rehabilitative approaches have been shown to improve balance, evidence of a reduction in falls has been mixed. Prior balance trials suggest that programs with highly challenging exercises had superior outcomes. We investigated the effects of a theoretically driven, progressive, highly challenging group exercise program on fall rate, balance, and fear of falling. Methods Twenty-three subjects with PD participated in this randomized cross-over trial. Subjects were randomly allocated to 3 months of active balance exercises or usual care followed by the reverse. During the active condition, subjects participated in a progressive, highly challenging group exercise program twice weekly for 90 minutes. Outcomes included a change in fall rate over the 3-month active period and differences in balance (Mini-BESTest), and fear of falling (Falls Efficacy Scale-International (FES-I)) between active and usual care conditions. Results: The effect of time on falls was significant (regression coefficient = −0.015 per day, p<0.001). The estimated rate ratio comparing incidence rates at time points one month apart was 0.632 (95% CI 0.524 to 0.763). Thus, there was an estimated 37% decline in fall rate per month (95% CI 24% to 48%). Improvements were also observed on the Mini-BESTest (p=0.037) and FES-I (p=0.059). Discussion and Conclusions The results of this study show that a theoretically based, highly challenging, and progressive exercise program was effective in reducing falls, improving balance, and reducing fear of falling in PD. PMID:26655100

  1. Partially reduced graphene oxide as highly efficient DNA nanoprobe.

    PubMed

    Wang, Yan-Hong; Deng, Hao-Hua; Liu, Yin-Huan; Shi, Xiao-Qiong; Liu, Ai-Lin; Peng, Hua-Ping; Hong, Guo-Lin; Chen, Wei

    2016-06-15

    This work investigates the effect of reduction degree on graphene oxide (GO)-DNA interaction and the fluorescence quenching mechanism. Partial reduced graphene oxide (pRGO), which maintains well water-dispersibility, is synthesized using a mild reduction method by incubating GO suspension under alkaline condition at room temperature. The fluorescence quenching enhances with the restoration degree of sp(2) carbon bonds and follows the static quenching mechanism. The binding constant values imply that pRGO has much stronger affinity with ssDNA than GO. Utilizing this highly efficient nanoprobe, a universal sensing strategy is proposed for homogeneous detection of DNA. Compared with the reported GO-based DNA, this present strategy has obvious advantages such as requirement of low nanoprobe dosage, significantly reduced background, fast fluorescence quenching, and improved sensitivity. Even without any amplification process, the limit of detection can reach as low as 50 pM.

  2. High concentration plasma-reduced plateletapheresis concentrates.

    PubMed

    Perseghin, Paolo

    2011-06-01

    Single-donor hyperconcentrated plateletapheresis (dry-platelets) collection has been introduced in the 90's as a part of the newly developed multi-component collection strategy. This approach allowed to safely collect multiple components from a single apheresis donation, i.e. RBC, FFP and/or plateletpheresis units. Dry-platelets are usually resuspended in additive solution to maintain an adequate pH during the storage period until use. Some concern existed about possible higher degrees of platelet activation in dry-platelets units when compared to standard concentration (1.0-1.6 × 10(6)/μL platelets) units and its possible correlation with lower in vivo efficiency and/or survival of the former units. Several authors investigated this specific issue, and dry-platelets units proved to be equally effective than standard concentration plateletpheresis units in recipients. The use of dry-platelets units may reduce (i) the risk of passive infusion of naturally occurring ABO-related hemolytic antibodies when donor O platelets are given to group A, B, or AB recipient, (ii) the risk of TRALI when multiparous donors undergo plateletpheresis. Furthermore, dry-platelet collection may allow for an increased amount of FFP sent to industry. Finally, hyperconcentrated platelet units may be used for "niche" indications, such as intrauterine platelet transfusion or, in case of autologous dry-platelet collection, for further freezing for long term storage in selected patients within onco-hematological settings.

  3. Reducing conditions are the key for efficient production of active ribonuclease inhibitor in Escherichia coli

    PubMed Central

    2011-01-01

    Background The eukaryotic RNase ribonuclease/angiogenin inhibitors (RI) are a protein group distinguished by a unique structure - they are composed of hydrophobic leucine-rich repeat motifs (LRR) and contain a high amount of reduced cysteine residues. The members of this group are difficult to produce in E. coli and other recombinant hosts due to their high aggregation tendency. Results In this work dithiothreitol (DTT) was successfully applied for improving the yield of correctly folded ribonuclease/angiogenin inhibitor in E. coli K12 periplasmic and cytoplasmic compartments. The feasibility of the in vivo folding concepts for cytoplasmic and periplasmic production were demonstrated at batch and fed-batch cultivation modes in shake flasks and at the bioreactor scale. Firstly, the best secretion conditions of RI in the periplasmic space were evaluated by using a high throughput multifactorial screening approach of a vector library, directly with the Enbase fed-batch production mode in 96-well plates. Secondly, the effect of the redox environment was evaluated in isogenic dsbA+ and dsbA- strains at the various cultivation conditions with reducing agents in the cultivation medium. Despite the fusion to the signal peptide, highest activities were found in the cytoplasmic fraction. Thus by removing the signal peptide the positive effect of the reducing agent DTT was clearly proven also for the cytoplasmic compartment. Finally, optimal periplasmic and cytoplasmic RI fed-batch production processes involving externally added DTT were developed in shake flasks and scaled up to the bioreactor scale. Conclusions DTT highly improved both, periplasmic and cytoplasmic accumulation and activity of RI at low synthesis rate, i.e. in constructs harbouring weak recombinant synthesis rate stipulating genetic elements together with cultivation at low temperature. In a stirred bioreactor environment RI folding was strongly improved by repeated pulse addition of DTT at low aeration

  4. Stem cell transplantation after reduced-intensity conditioning for sickle cell disease.

    PubMed

    Matthes-Martin, Susanne; Lawitschka, Anita; Fritsch, Gerhard; Lion, Thomas; Grimm, Brigitte; Breuer, Sabine; Boztug, Heidrun; Karlhuber, Susanne; Holter, Wolfgang; Peters, Christina; Minkov, Milen

    2013-04-01

    Sickle cell disease (SCD) is still associated with substantial morbidity and reduced life expectancy. Disease-related mortality rises to 14% in adolescents and young adults. Overall and disease-free survival following haematopoietic stem cell transplantation (HSCT) is 90% and 95%, respectively. To reduce transplant-associated late effects, the feasibility of a highly immunosuppressive reduced-intensity conditioning (RIC) regimen was explored in children with SCD and a matched sibling donor. Eight patients (median age, 9 yr) and symptomatic SCD were included. The conditioning regimen consisted of fludarabine, melphalan and either thiotepa or total lymphoid irradiation plus antithymocyte globuline or alemtuzumab. The graft was bone marrow in seven and cord blood in one case. The conditioning regimen was well tolerated and no severe infectious complications occurred. All patients displayed mixed chimaerism on day +28. After a median follow-up of 4 yr, 3/8 patients have mixed leucocyte chimaerism and 8/8 patients have 100% donor erythropoiesis. HSCT from matched sibling donors following a RIC regimen was well tolerated and resulted in cure in all patients studied. If confirmed in larger patient cohorts, these observations will have important implications for the indications of HSCT in children with SCD.

  5. High pressure droplet burning experiments in reduced gravity

    NASA Technical Reports Server (NTRS)

    Chauveau, Christian; Goekalp, Iskender

    1995-01-01

    A parametric investigation of single droplet gasification regimes is helpful in providing the necessary physical ideas for sub-grid models used in spray combustion numerical prediction codes. A research program has been initiated at the LCSR to explore the vaporization regimes of single and interacting hydrocarbon and liquid oxygen droplets under high pressure conditions. This paper summarizes the status of the LCSR program on the high pressure burning of single fuel droplets; recent results obtained under normal and reduced gravity conditions with suspended droplets are presented. In the work described here, parabolic flights of the CNES Caravelle is used to create a reduced gravity environment of the order of 10(exp -2) g(sub O). For all the droplet burning experiments reported here, the suspended droplet initial diameters are scattered around 1.5 mm; and the ambient air temperature is 300 K. The ambient pressure is varied between 0.1 MPa and 12 MPa. Four fuels are investigated: methanol (Pc = 7.9 MPa), n-heptane (Pc = 2.74 MPa), n-hexane (Pc = 3.01 MPa) and n-octane (Pc = 2.48 MPa).

  6. Anoxic biodegradation of dimethyl phthalate (DMP) by activated sludge cultures under nitrate-reducing conditions.

    PubMed

    Wu, Dong-lei; Hu, Bao-lan; Zheng, Ping; Qaisar, Mahmood

    2007-01-01

    Worldwide extensive use of plasticized plastics has resulted in phthalates pollution in different environment. Nitrates from industry and agriculture are also widely disseminated in the soils, natural waters and wastewaters. Dimethyl phthalate (DMP) biodegradation by activated sludge cultures under nitrate-reducing conditions was investigated. Under one optimized condition, DMP was biodegraded from 102.20 mg/L to undetectable level in 56 h under anoxic conditions and its reaction fitted well with the first-order kinetics. Using the high-performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC-MS) analysis, mono-methyl phthalate (MMP) and phthalic acid (PA) were detected as the major intermediates of DMP biodegradation. When combined with the determination of chemical oxygen demand (COD(Cr)) removal capacity and pH, DMP was found to be mineralized completely under anoxic conditions. The biodegradation pathway was proposed as DMP -->MMP-->PA-->...-->CO2 + H2O. The molar ratio ofDMP to nitrate consumed was found to be 9.0:1, which agrees well with the theoretical stoichiometric values of DMP biodegradation by nitrate-reducing bacteria. The results of the non-linear simulation showed that the optimum pH and temperature for the degradation were 7.56 and 31.4 degrees C, respectively.

  7. Observations of swash under highly dissipative conditions

    NASA Astrophysics Data System (ADS)

    Ruessink, B. G.; Kleinhans, M. G.; van den Beukel, P. G. L.

    1998-02-01

    Video measurements of swash were made at the low-sloping beach of the multiple bar system at Terschelling, Netherlands. The majority of the measurements were conducted under highly dissipative conditions with Iribarren numbers ξ0 (the ratio of beach slope to the square root of offshore wave steepness) less than 0.2. Infragravity (0.004-0.05 Hz) waves dominated the swash with an average ratio of infragravity and total swash height Rig/R of 0.85. Using linear regression we investigated the dependence of swash parameters on environmental conditions such as short-wave height, period, and local beach slope. On average, Rig was about 30% of the offshore wave height H0; the slope in the linear H0 dependence of Rig amounted to only 0.18, considerably smaller than that observed on steeper beaches. The data set shows evidence for saturation of the higher infragravity frequencies for ξ0 less than, roughly, 0.27. In our opinion, this saturation caused the constant of proportionality in the linear relationship between Rig/H0 and ξ0 to be significantly larger than that observed under higher Iribarren number regimes. The saturated tails of the swash spectra had an approximate f-3 roll-off (where f is frequency), whereas, in general, the nonsaturated parts were white. This lack of significant peaks casts doubt on the causality between infragravity waves and nearshore bars.

  8. Adaptation of iron requirement to hypoxic conditions at high altitude.

    PubMed

    Gassmann, Max; Muckenthaler, Martina U

    2015-12-15

    Adequate acclimatization time to enable adjustment to hypoxic conditions is one of the most important aspects for mountaineers ascending to high altitude. Accordingly, most reviews emphasize mechanisms that cope with reduced oxygen supply. However, during sojourns to high altitude adjustment to elevated iron demand is equally critical. Thus in this review we focus on the interaction between oxygen and iron homeostasis. We review the role of iron 1) in the oxygen sensing process and erythropoietin (Epo) synthesis, 2) in gene expression control mediated by the hypoxia-inducible factor-2 (HIF-2), and 3) as an oxygen carrier in hemoglobin, myoglobin, and cytochromes. The blood hormone Epo that is abundantly expressed by the kidney under hypoxic conditions stimulates erythropoiesis in the bone marrow, a process requiring high iron levels. To ensure that sufficient iron is provided, Epo-controlled erythroferrone that is expressed in erythroid precursor cells acts in the liver to reduce expression of the iron hormone hepcidin. Consequently, suppression of hepcidin allows for elevated iron release from storage organs and enhanced absorption of dietary iron by enterocytes. As recently observed in sojourners at high altitude, however, iron uptake may be hampered by reduced appetite and gastrointestinal bleeding. Reduced iron availability, as observed in a hypoxic mountaineer, enhances hypoxia-induced pulmonary hypertension and may contribute to other hypoxia-related diseases. Overall, adequate systemic iron availability is an important prerequisite to adjust to high-altitude hypoxia and may have additional implications for disease-related hypoxic conditions. Copyright © 2015 the American Physiological Society.

  9. The Proteome of Dissimilatory Metal-reducing Microorganism Geobacter Sulfurreducens under Various Growth Conditions

    SciTech Connect

    Ding, Y-H R.; Hixson, Kim K.; Giometti, Carol S.; Stanley, A; Esteve-Nunez, A; Khare, Tripti; Tollaksen, Sandra L.; Zhu, Wenhong; Adkins, Joshua N.; Lipton, Mary S.; Smith, Richard D.; Mester, Tunde; Lovley, Derek R.

    2006-05-16

    The global protein analysis of Geobacter sulfurreducens, a model for the Geobacter species that predominate in many Fe(III)-reducing subsurface environments, was characterized with ultra high pressure liquid chromatography and mass spectrometry using accurate mass and time (AMT) tags as well as with more traditional two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Cells were grown under eight different growth conditions in order to enhance the potential that genes would be expressed. Over 3,187 gene products, representing about 92% of the total predicted gene products in the genome, were detected. The AMT approach was able to identify a much higher number of proteins than could be detected with the 2-D PAGE approach. A high proportion of predicted proteins in most protein role categories were detected with the highest number of proteins identified in the hypothetical protein role category. Furthermore, 91 c-type cytochromes of 111 predicted genes in the G. sulfurreducens genome were identified. Localization studies indicated that computational predictions of cytochrome location were limited. Differences in the abundance of cytochromes and other proteins under different growth conditions provided information for future functional analysis of these proteins. These results demonstrate that a high percentage of the predicted proteins in the G. sulfurreducens genome are produced and that the AMT approach provides a rapid method for comparing differential expression of proteins under different growth conditions in this organism.

  10. Post-conditioning experience with acute or chronic inflammatory pain reduces contextual fear conditioning in the rat.

    PubMed

    Johnston, Ian N; Maier, Steven F; Rudy, Jerry W; Watkins, Linda R

    2012-01-15

    There is evidence that pain can impact cognitive function in people. The present study evaluated whether Pavlovian fear conditioning in rats would be reduced if conditioning were followed by persistent inflammatory pain induced by a subcutaneous injection of dilute formalin or complete Freund's adjuvant (CFA) on the dorsal lumbar surface of the back. Formalin-induced pain specifically impaired contextual fear conditioning but not auditory cue conditioning (Experiment 1A). Moreover, formalin pain only impaired contextual fear conditioning if it was initiated within 1h of conditioning and did not have a significant effect if initiated 2, 8 or 32 h after (Experiments 1A and 1B). Experiment 2 showed that formalin pain initiated after a session of context pre-exposure reduced the ability of that pre-exposure to facilitate contextual fear when the rat was limited to a brief exposure to the context during conditioning. Similar impairments in context- but not CS-fear conditioning were also observed if the rats received an immediate post-conditioning injection with CFA (Experiment 3). Finally, we confirmed that formalin and CFA injected s.c. on the back induced pain-indicative behaviours, hyperalgesia and allodynia with a similar timecourse to intraplantar injections (Experiment 4). These results suggest that persistent pain impairs learning in a hippocampus-dependent task, and may disrupt processes that encode experiences into long-term memory.

  11. Cognitive manipulation targeted at decreasing the conditioning pain perception reduces the efficacy of conditioned pain modulation.

    PubMed

    Nir, Rony-Reuven; Yarnitsky, David; Honigman, Liat; Granot, Michal

    2012-01-01

    Although painfulness of the conditioning stimulus (CS) is required for the activation of conditioned pain modulation (CPM), it is still unclear whether CPM expression depends on the objective physical intensity of the CS or the subjective perception of its pain. Accordingly, we cognitively manipulated the perceived CS pain, rendering the physical aspects of the CPM paradigm untouched. Baseline CPM was measured among 48 young healthy male subjects using the parallel paradigm with contact heat as test pain and hand immersion in hot water as CS. Subjects were then randomized into 4 groups, all of which were cognitively manipulated as to the CS-induced pain: group 1, placebo (CS less painful); group 2, nocebo (CS more painful); and groups 3 and 4, the informed control groups for groups 1 and 2, respectively. CPM was reassessed after the manipulation. Comparing the groups by MANCOVA (multivariate analysis of covariance) revealed that placebo exerted decreased CS pain and consequent attenuation of CPM magnitudes, while nocebo elicited increased CS pain, but without CPM elevation (P<.0001). Within the placebo group, the reduction in CS pain was associated with diminished CPM responses (r=0.767; P=.001); however, no such relationship characterized the nocebo group. Pain inhibition under CPM seems to depend on the perceived level of the CS pain rather than solely its physical intensity. Cognitively decreasing the perceived CS pain attenuates CPM magnitude, although a ceiling effect may limit CPM enhancement after cognitively increased CS pain. These findings emphasize the relevance of cognitive mechanisms in determining endogenous analgesia processes in humans. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  12. Development of Boundary Condition Independent Reduced Order Thermal Models using Proper Orthogonal Decomposition

    NASA Astrophysics Data System (ADS)

    Raghupathy, Arun; Ghia, Karman; Ghia, Urmila

    2008-11-01

    Compact Thermal Models (CTM) to represent IC packages has been traditionally developed using the DELPHI-based (DEvelopment of Libraries of PHysical models for an Integrated design) methodology. The drawbacks of this method are presented, and an alternative method is proposed. A reduced-order model that provides the complete thermal information accurately with less computational resources can be effectively used in system level simulations. Proper Orthogonal Decomposition (POD), a statistical method, can be used to reduce the order of the degree of freedom or variables of the computations for such a problem. POD along with the Galerkin projection allows us to create reduced-order models that reproduce the characteristics of the system with a considerable reduction in computational resources while maintaining a high level of accuracy. The goal of this work is to show that this method can be applied to obtain a boundary condition independent reduced-order thermal model for complex components. The methodology is applied to the 1D transient heat equation.

  13. Disrupting astrocyte-neuron lactate transfer persistently reduces conditioned responses to cocaine.

    PubMed

    Boury-Jamot, B; Carrard, A; Martin, J L; Halfon, O; Magistretti, P J; Boutrel, B

    2016-08-01

    A central problem in the treatment of drug addiction is the high risk of relapse often precipitated by drug-associated cues. The transfer of glycogen-derived lactate from astrocytes to neurons is required for long-term memory. Whereas blockade of drug memory reconsolidation represents a potential therapeutic strategy, the role of astrocyte-neuron lactate transport in long-term conditioning has received little attention. By infusing an inhibitor of glycogen phosphorylase into the basolateral amygdala of rats, we report that disruption of astrocyte-derived lactate not only transiently impaired the acquisition of a cocaine-induced conditioned place preference but also persistently disrupted an established conditioning. The drug memory was rescued by L-Lactate co-administration through a mechanism requiring the synaptic plasticity-related transcription factor Zif268 and extracellular signal-regulated kinase (ERK) signalling pathway but not the brain-derived neurotrophic factor (Bdnf). The long-term amnesia induced by glycogenolysis inhibition and the concomitant decreased expression of phospho-ERK were both restored with L-Lactate co-administration. These findings reveal a critical role for astrocyte-derived lactate in positive memory formation and highlight a novel amygdala-dependent reconsolidation process, whose disruption may offer a novel therapeutic target to reduce the long-lasting conditioned responses to cocaine.

  14. Post-training glucocorticoid receptor activation during Pavlovian conditioning reduces Pavlovian-instrumental transfer in rats.

    PubMed

    Pielock, Steffi M; Sommer, Susanne; Hauber, Wolfgang

    2013-03-01

    Considerable evidence suggests that glucocorticoid receptor activation can enhance memory consolidation in Pavlovian learning tasks. For instance, post-training injections of the synthetic glucocorticoid receptor agonist dexamethasone increased conditioned responding to reward-predictive Pavlovian stimuli. Here we explored whether post-training dexamethasone injections can enhance appetitive Pavlovian learning and amplify the ability of Pavlovian stimuli to invigorate instrumental behaviour, a phenomenon termed Pavlovian-instrumental transfer (PIT). Animals were given 8 training days with two sessions per day, an instrumental training session in the morning and a Pavlovian training session in the afternoon. Dexamethasone or vehicle injections were administered daily immediately after Pavlovian training sessions. In a subsequent transfer test, we measured the general PIT effect, i.e. the enhancement of lever pressing for expected reward during presentation of an appetitive Pavlovian stimulus predictive for the same reward. Repeated high-dose (1.2 mg/kg, i.p.) dexamethasone injections elicited pronounced body weight loss, markedly reduced instrumental performance and left Pavlovian learning unaltered, whereas repeated low-dose (3 μg/kg, i.p.) dexamethasone injections inhibited body weight gain, slightly reduced instrumental performance and left Pavlovian learning unaltered during training. Importantly, in rats subjected to high- and low-dose dexamethasone injections, the overall response rates and the PIT effect were reduced in the transfer test. Thus, dexamethasone given after Pavlovian training was not able to amplify the invigorating effects of Pavlovian stimuli on instrumental action. Considerable evidence suggests that body weight changes after repeated low- and high-dose dexamethasone treatment as observed here are associated with muscle atrophy that could impair response capabilities. However, our data suggest that impaired response capabilities are not a

  15. Microbial Thiocyanate Utilization under Highly Alkaline Conditions

    PubMed Central

    Sorokin, Dimitry Y.; Tourova, Tatyana P.; Lysenko, Anatoly M.; Kuenen, J. Gijs

    2001-01-01

    Three kinds of alkaliphilic bacteria able to utilize thiocyanate (CNS−) at pH 10 were found in highly alkaline soda lake sediments and soda soils. The first group included obligate heterotrophs that utilized thiocyanate as a nitrogen source while growing at pH 10 with acetate as carbon and energy sources. Most of the heterotrophic strains were able to oxidize sulfide and thiosulfate to tetrathionate. The second group included obligately autotrophic sulfur-oxidizing alkaliphiles which utilized thiocyanate nitrogen during growth with thiosulfate as the energy source. Genetic analysis demonstrated that both the heterotrophic and autotrophic alkaliphiles that utilized thiocyanate as a nitrogen source were related to the previously described sulfur-oxidizing alkaliphiles belonging to the gamma subdivision of the division Proteobacteria (the Halomonas group for the heterotrophs and the genus Thioalkalivibrio for autotrophs). The third group included obligately autotrophic sulfur-oxidizing alkaliphilic bacteria able to utilize thiocyanate as a sole source of energy. These bacteria could be enriched on mineral medium with thiocyanate at pH 10. Growth with thiocyanate was usually much slower than growth with thiosulfate, although the biomass yield on thiocyanate was higher. Of the four strains isolated, the three vibrio-shaped strains were genetically closely related to the previously described sulfur-oxidizing alkaliphiles belonging to the genus Thioalkalivibrio. The rod-shaped isolate differed from the other isolates by its ability to accumulate large amounts of elemental sulfur inside its cells and by its ability to oxidize carbon disulfide. Despite its low DNA homology with and substantial phenotypic differences from the vibrio-shaped strains, this isolate also belonged to the genus Thioalkalivibrio according to a phylogenetic analysis. The heterotrophic and autotrophic alkaliphiles that grew with thiocyanate as an N source possessed a relatively high level of cyanase

  16. Synthesis of Ti Oxides at Reducing Conditions: Implications for Beamline Standards and Cosmochemistry

    NASA Technical Reports Server (NTRS)

    Righter, K.; Pando, K. A.; Butterworth, A. L.; Gainsforth, Z.; Jilly-Rehak, C. E.; Westphal, A. J.

    2017-01-01

    These initial experiments demonstrate the great potential for synthesizing customized compounds for use as standards, or in buffering experiments at reducing conditions. We are also investigating Cr and V oxides, as well as compounds containing these elements such as FeV2O4 and FeCr2O4. Oxygen fugacity exerts a major control on mineral major element chemistry and elemental valence of minerals in any plane-tary compositional system [1]. For Earth, Fe is multivalent ranging from nearly Fe0 at low fO2 in the deep mantle to Fe2+ to Fe3+ at high low fO2. For solar nebular and meteoritic materials fO2 ranges from near IW to 10 log fO2 units below the IW buffer [1]. Phases in CAIs, for example, contain no Fe2+, but may contain Ti4+, Ti3+, or Ti2+, and Cr3+ or Cr2+, and V3+ or V2+ [1,2,3]. De-tailed study of inclusions may reveal important differences in fO2 thus reflecting different environments in the solar nebula [4]. XANES, FEG-SEM, and TEM can reveal such variations in micro and nano samples such as Stardust and cosmic dust particles [5], but successful application to reduced conditions depends upon the availability of well characterized standards. Acquiring appropriate standards for reduced phases that contain Ti3+ or Ti2+, Cr3+ or Cr2+, and V3+ or V2+ can be a challenge. Here we report our preliminary results at synthesizing reduced Ti bearing standards, and focus on the preliminary characterization.

  17. Opportunities to Reduce Air-Conditioning Loads Through Lower Cabin Soak Temperatures

    SciTech Connect

    Farrington, R.; Cuddy, M.; Keyser, M.; Rugh, J.

    1999-07-12

    Air-conditioning loads can significantly reduce electric vehicle (EV) range and hybrid electric vehicle (HEV) fuel economy. In addition, a new U. S. emissions procedure, called the Supplemental Federal Test Procedure (SFTP), has provided the motivation for reducing the size of vehicle air-conditioning systems in the United States. The SFTP will measure tailpipe emissions with the air-conditioning system operating. If the size of the air-conditioning system is reduced, the cabin soak temperature must also be reduced, with no penalty in terms of passenger thermal comfort. This paper presents the impact of air-conditioning on EV range and HEV fuel economy, and compares the effectiveness of advanced glazing and cabin ventilation. Experimental and modeled results are presented.

  18. Reduced-intensity conditioning allogeneic hematopoietic-cell transplantation for older patients with acute myeloid leukemia

    PubMed Central

    Goyal, Gaurav; Gundabolu, Krishna; Vallabhajosyula, Saraschandra; Silberstein, Peter T.; Bhatt, Vijaya Raj

    2016-01-01

    Elderly patients (>60 years) with acute myeloid leukemia have a poor prognosis with a chemotherapy-alone approach. Allogeneic hematopoietic-cell transplantation (HCT) can improve overall survival (OS). However, myeloablative regimens can have unacceptably high transplant-related mortality (TRM) in an unselected group of older patients. Reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning regimens preserve the graft-versus-leukemia effects but reduce TRM. NMA regimens result in minimal cytopenia and may not require stem cell support for restoring hematopoiesis. RIC regimens, intermediate in intensity between NMA and myeloablative regimens, can cause prolonged myelosuppresion and usually require stem cell support. A few retrospective and prospective studies suggest a possibility of lower risk of relapse with myeloablative HCT in fit older patients with lower HCT comorbidity index; however, RIC and NMA HCTs have an important role in less-fit patients and those with significant comorbidities because of lower TRM. Whether early tapering of immunosuppression, monitoring of minimal residual disease, and post-transplant maintenance therapy can improve the outcomes of RIC and NMA HCT in elderly patients will require prospective trials. PMID:27247754

  19. Formation of diphenylthioarsinic acid from diphenylarsinic acid under anaerobic sulfate-reducing soil conditions.

    PubMed

    Hisatomi, Shihoko; Guan, Ling; Nakajima, Mami; Fujii, Kunihiko; Nonaka, Masanori; Harada, Naoki

    2013-11-15

    Diphenylarsinic acid (DPAA) is a toxic phenylarsenical compound often found around sites contaminated with phenylarsenic chemical warfare agents, diphenylcyanoarsine or diphenylchloroarsine, which were buried in soil after the World Wars. This research concerns the elucidation of the chemical structure of an arsenic metabolite transformed from DPAA under anaerobic sulfate-reducing soil conditions. In LC/ICP-MS analysis, the retention time of the metabolite was identical to that of a major phenylarsenical compound synthesized by chemical reaction of DPAA and hydrogen sulfide. Moreover the mass spectra for the two compounds measured using LC/TOF-MS were similar. Subsequent high resolution mass spectral analysis indicated that two major ions at m/z 261 and 279, observed on both mass spectra, were attributable to C12H10AsS and C12H12AsSO, respectively. These findings strongly suggest that the latter ion is the molecular-related ion ([M+H](+)) of diphenylthioarsinic acid (DPTA; (C6H5)2AsS(OH)) and the former ion is its dehydrated fragment. Thus, our results reveal that DPAA can be transformed to DPTA, as a major metabolite, under sulfate-reducing soil conditions. Moreover, formation of diphenyldithioarsinic acid and subsequent dimerization were predicted by the chemical reaction analysis of DPAA with hydrogen sulfide. This is the first report to elucidate the occurrence of DPAA-thionation in an anaerobic soil.

  20. Multiple electron transfer systems in oxygen reducing biocathodes revealed by different conditions of aeration/agitation.

    PubMed

    Rimboud, Mickaël; Bergel, Alain; Erable, Benjamin

    2016-08-01

    Oxygen reducing biocathodes were formed at -0.2V/SCE (+0.04V/SHE) from compost leachate. Depending on whether aeration was implemented or not, two different redox systems responsible for the electrocatalysis of oxygen reduction were evidenced. System I was observed at low potential (-0.03V/SHE) on cyclic voltammetries (CVs). It appeared during the early formation of the biocathode (few hours) and resisted the hydrodynamic conditions induced by the aeration. System II was observed at higher potential on CV (+0.46V/SHE); it required a longer lag time (up to 10days) and quiescent conditions to produce an electrochemical signal. The hydrodynamic effects produced by the forced aeration led to its extinction. From their different behaviors and examples in the literature, system I was identified as being a membrane-bound cytochrome-related molecule, while system II was identified as a soluble redox mediator excreted by the biofilm. This study highlighted the importance of controlling the local hydrodynamics to design efficient oxygen reducing biocathodes able to operate at high potential.

  1. Acetate Production from Oil under Sulfate-Reducing Conditions in Bioreactors Injected with Sulfate and Nitrate

    PubMed Central

    Callbeck, Cameron M.; Agrawal, Akhil

    2013-01-01

    Oil production by water injection can cause souring in which sulfate in the injection water is reduced to sulfide by resident sulfate-reducing bacteria (SRB). Sulfate (2 mM) in medium injected at a rate of 1 pore volume per day into upflow bioreactors containing residual heavy oil from the Medicine Hat Glauconitic C field was nearly completely reduced to sulfide, and this was associated with the generation of 3 to 4 mM acetate. Inclusion of 4 mM nitrate inhibited souring for 60 days, after which complete sulfate reduction and associated acetate production were once again observed. Sulfate reduction was permanently inhibited when 100 mM nitrate was injected by the nitrite formed under these conditions. Pulsed injection of 4 or 100 mM nitrate inhibited sulfate reduction temporarily. Sulfate reduction resumed once nitrate injection was stopped and was associated with the production of acetate in all cases. The stoichiometry of acetate formation (3 to 4 mM formed per 2 mM sulfate reduced) is consistent with a mechanism in which oil alkanes and water are metabolized to acetate and hydrogen by fermentative and syntrophic bacteria (K. Zengler et al., Nature 401:266–269, 1999), with the hydrogen being used by SRB to reduce sulfate to sulfide. In support of this model, microbial community analyses by pyrosequencing indicated SRB of the genus Desulfovibrio, which use hydrogen but not acetate as an electron donor for sulfate reduction, to be a major community component. The model explains the high concentrations of acetate that are sometimes found in waters produced from water-injected oil fields. PMID:23770914

  2. Acetate production from oil under sulfate-reducing conditions in bioreactors injected with sulfate and nitrate.

    PubMed

    Callbeck, Cameron M; Agrawal, Akhil; Voordouw, Gerrit

    2013-08-01

    Oil production by water injection can cause souring in which sulfate in the injection water is reduced to sulfide by resident sulfate-reducing bacteria (SRB). Sulfate (2 mM) in medium injected at a rate of 1 pore volume per day into upflow bioreactors containing residual heavy oil from the Medicine Hat Glauconitic C field was nearly completely reduced to sulfide, and this was associated with the generation of 3 to 4 mM acetate. Inclusion of 4 mM nitrate inhibited souring for 60 days, after which complete sulfate reduction and associated acetate production were once again observed. Sulfate reduction was permanently inhibited when 100 mM nitrate was injected by the nitrite formed under these conditions. Pulsed injection of 4 or 100 mM nitrate inhibited sulfate reduction temporarily. Sulfate reduction resumed once nitrate injection was stopped and was associated with the production of acetate in all cases. The stoichiometry of acetate formation (3 to 4 mM formed per 2 mM sulfate reduced) is consistent with a mechanism in which oil alkanes and water are metabolized to acetate and hydrogen by fermentative and syntrophic bacteria (K. Zengler et al., Nature 401:266-269, 1999), with the hydrogen being used by SRB to reduce sulfate to sulfide. In support of this model, microbial community analyses by pyrosequencing indicated SRB of the genus Desulfovibrio, which use hydrogen but not acetate as an electron donor for sulfate reduction, to be a major community component. The model explains the high concentrations of acetate that are sometimes found in waters produced from water-injected oil fields.

  3. Conditioning rainfall-runoff model parameters to reduce prediction uncertainty in ungauged basins

    NASA Astrophysics Data System (ADS)

    Visessri, S.; McIntyre, N.; Maksimovic, C.

    2012-12-01

    Conditioning rainfall-runoff model parameters in ungauged catchments in Thailand presents problems common to ungauged basins involving data availability, data quality, and rainfall-runoff model suitability, which all contribute to prediction uncertainty. This paper attempts to improve the estimation of streamflow in ungauged basins and reduce associated uncertainties using the approaches of conditioning the prior parameter space. 35 catchments from the upper Ping River basin, Thailand are selected as a case study. The catchments have a range of attributes e.g. catchment sizes 20-6350 km2, elevations 632-1529 m above sea level. and annual rainfall 846-1447 mm/year. For each catchment, three indices - rainfall-runoff elasticity, base flow index and runoff coefficient - are calculated using the observed rainfall-runoff data and regression equations relating these indices to the catchment attributes are identified. Uncertainty in expected indices is defined by the regression error distribution, approximated by a Gaussian model. The IHACRES model is applied for simulating streamflow. The IHACRES parameters are randomly sampled from their presumed prior parameter space. For each sampled parameter set, the streamflow and hence the three indices are modelled. The parameter sets are conditioned on the probability distributions of the regionalised indices, allowing ensemble predictions to be made. The objective function, NSE, calculated for daily and weekly time steps from the water years 1995-2000, is used to assess model performance. Ability to capture observed streamflow and the precision of the estimate is evaluated using reliability and sharpness measures. Similarity in modelled and expected indices contributes to good objective function values. Using only the regionalised runoff coefficient to condition the model yields better NSE values compared to using either only the rainfall-runoff elasticity or only the base flow index. Conditioning on the runoff coefficient

  4. Sulfate-reducing bacteria mediate thionation of diphenylarsinic acid under anaerobic conditions.

    PubMed

    Guan, Ling; Shiiya, Ayaka; Hisatomi, Shihoko; Fujii, Kunihiko; Nonaka, Masanori; Harada, Naoki

    2015-02-01

    Diphenylarsinic acid (DPAA) is often found as a toxic intermediate metabolite of diphenylchloroarsine or diphenylcyanoarsine that were produced as chemical warfare agents and were buried in soil after the World Wars. In our previous study Guan et al. (J Hazard Mater 241-242:355-362, 2012), after application of sulfate and carbon sources, anaerobic transformation of DPAA in soil was enhanced with the production of diphenylthioarsinic acid (DPTAA) as a main metabolite. This study aimed to isolate and characterize anaerobic soil microorganisms responsible for the metabolism of DPAA. First, we obtained four microbial consortia capable of transforming DPAA to DPTAA at a high transformation rate of more than 80% after 4 weeks of incubation. Sequencing for the bacterial 16S rRNA gene clone libraries constructed from the consortia revealed that all the positive consortia contained Desulfotomaculum acetoxidans species. In contrast, the absence of dissimilatory sulfite reductase gene (dsrAB) which is unique to sulfate-reducing bacteria was confirmed in the negative consortia showing no DPAA reduction. Finally, strain DEA14 showing transformation of DPAA to DPTAA was isolated from one of the positive consortia. The isolate was assigned to D. acetoxidans based on the partial 16S rDNA sequence analysis. Thionation of DPAA was also carried out in a pure culture of a known sulfate-reducing bacterial strain, Desulfovibrio aerotolerans JCM 12613(T). These facts indicate that sulfate-reducing bacteria are microorganisms responsible for the transformation of DPAA to DPTAA under anaerobic conditions.

  5. In situ BTEX biotransformation under enhanced nitrate- and sulfate-reducing conditions

    SciTech Connect

    Reinhard, M.; Shang, S.; Kitanidis, P.K.; Orwin, E.; Hopkins, G.D.; LeBron, C.A.

    1997-01-01

    In situ anaerobic biotransformation of BTEX (benzene, toluene, ethylbenzene, o-xylene, and m-xylene) was investigated under enhanced nitrate- and sulfate-reducing conditions. Controlled amounts of BTEX compounds added to slugs of treated groundwater were released into a gasoline-contaminated aquifer at Seal Beach, CA. In a series of studies, the slugs, 470-1700 L in volume, were released into the aquifer through a multi-port injection/extraction well and were subsequently withdrawn over a 2-3 month period. To evaluate unamended in situ conditions, the injectate was treated with granular activated carbon (GAC) and augmented with bromide as a tracer. To evaluate nitrate- and sulfate-reducing conditions, the injectate was also deionized and augmented with 200-300 {mu}g/L BTEX, nitrate or sulfate, and background electrolytes. Under unamended conditions, transformation appeared to be limited to the slow removal of toluene and m,p-xylene (i.e. sum of m+p-xylene). Under nitrate-reducing conditions, toluene, ethylbenzene, and m-xylene were transformed without a lag phase in less than 10 days, and o-xylene was transformed in 72 days. Under sulfate-reducing conditions, toluene, m-xylene and o-xylene were completely transformed in less then 50 days, and ethylbenzene was removed in 60 days. Benzene appeared to be removed under sulfate-reducing conditions, but the trend was pronounced only at some levels. 47 refs., 11 figs., 2 tabs.

  6. D-cycloserine does not facilitate fear extinction by reducing conditioned stimulus processing or promoting conditioned inhibition to contextual cues.

    PubMed

    Baker, Kathryn D; McNally, Gavan P; Richardson, Rick

    2012-09-14

    The NMDA receptor partial agonist d-cycloserine (DCS) enhances the extinction of learned fear in rats and exposure therapy in humans with anxiety disorders. Despite these benefits, little is known about the mechanisms by which DCS promotes the loss of fear. The present study examined whether DCS augments extinction retention (1) through reductions in conditioned stimulus (CS) processing or (2) by promoting the development of conditioned inhibition to contextual cues. Rats administered DCS prior to extinction showed enhanced long-term extinction retention (Experiments 3 and 4). The same nonreinforced CS procedure used in extinction also reduced freezing at test when presented as pre-exposure before conditioning, demonstrating latent inhibition (Experiment 1). DCS administered shortly prior to pre-exposure had no effect on latent inhibition using parameters which produced weak (Experiment 2) or strong (Experiment 3) expression of latent inhibition. Therefore, DCS facilitated learning involving CS-alone exposures, but only when these exposures occurred after (extinction) and not before (latent inhibition) conditioning. We also used a retardation test procedure to examine whether the extinction context gained inhibitory properties for rats given DCS prior to extinction. With three different footshock intensities, there was no evidence that DCS promoted accrual of associative inhibition to the extinction context (Experiment 4). The present findings demonstrate that DCS does not facilitate extinction by reducing CS processing or causing the extinction context to become a conditioned inhibitor. Investigations into the mechanisms underlying the augmentation of extinction by DCS are valuable for understanding how fear can be inhibited.

  7. Odor tracking in sharks is reduced under future ocean acidification conditions.

    PubMed

    Dixson, Danielle L; Jennings, Ashley R; Atema, Jelle; Munday, Philip L

    2015-04-01

    Recent studies show that ocean acidification impairs sensory functions and alters the behavior of teleost fishes. If sharks and other elasmobranchs are similarly affected, this could have significant consequences for marine ecosystems globally. Here, we show that projected future CO2 levels impair odor tracking behavior of the smooth dogfish (Mustelus canis). Adult M. canis were held for 5 days in a current-day control (405 ± 26 μatm) and mid (741 ± 22 μatm) or high CO2 (1064 ± 17 μatm) treatments consistent with the projections for the year 2100 on a 'business as usual' scenario. Both control and mid CO2 -treated individuals maintained normal odor tracking behavior, whereas high CO2 -treated sharks significantly avoided the odor cues indicative of food. Control sharks spent >60% of their time in the water stream containing the food stimulus, but this value fell below 15% in high CO2 -treated sharks. In addition, sharks treated under mid and high CO2 conditions reduced attack behavior compared to the control individuals. Our findings show that shark feeding could be affected by changes in seawater chemistry projected for the end of this century. Understanding the effects of ocean acidification on critical behaviors, such as prey tracking in large predators, can help determine the potential impacts of future ocean acidification on ecosystem function. © 2014 John Wiley & Sons Ltd.

  8. Anaerobic Oxidation of [1,2-14C]Dichloroethene under Mn(IV)-Reducing Conditions

    PubMed Central

    Bradley, Paul M.; Landmeyer, James E.; Dinicola, Richard S.

    1998-01-01

    Anaerobic oxidation of [1,2-14C]dichloroethene to 14CO2 under Mn(IV)-reducing conditions was demonstrated. The results indicate that oxidative degradation of partially chlorinated solvents like dichloroethene can be significant even under anoxic conditions and demonstrate the potential importance of Mn(IV) reduction for remediation of chlorinated groundwater contaminants. PMID:16349554

  9. Anaerobic oxidation of [1,2-14C]Dichloroethene under Mn(IV)-reducing conditions

    USGS Publications Warehouse

    Bradley, Paul M.; Landmeyer, James E.; Dinicola, Richard S.

    1998-01-01

    Anaerobic oxidation of [1,2-14C]dichloroethene to14CO2 under Mn(IV)-reducing conditions was demonstrated. The results indicate that oxidative degradation of partially chlorinated solvents like dichloroethene can be significant even under anoxic conditions and demonstrate the potential importance of Mn(IV) reduction for remediation of chlorinated groundwater contaminants.

  10. The Role of Alexithymia in Reduced Eye-Fixation in Autism Spectrum Conditions

    ERIC Educational Resources Information Center

    Bird, Geoffrey; Press, Clare; Richardson, Daniel C.

    2011-01-01

    Eye-tracking studies have demonstrated mixed support for reduced eye fixation when looking at social scenes in individuals with Autism Spectrum Conditions (ASC). We present evidence that these mixed findings are due to a separate condition--alexithymia--that is frequently comorbid with ASC. We find that in adults with ASC, autism symptom severity…

  11. The Role of Alexithymia in Reduced Eye-Fixation in Autism Spectrum Conditions

    ERIC Educational Resources Information Center

    Bird, Geoffrey; Press, Clare; Richardson, Daniel C.

    2011-01-01

    Eye-tracking studies have demonstrated mixed support for reduced eye fixation when looking at social scenes in individuals with Autism Spectrum Conditions (ASC). We present evidence that these mixed findings are due to a separate condition--alexithymia--that is frequently comorbid with ASC. We find that in adults with ASC, autism symptom severity…

  12. High efficiency air cycle air conditioning system

    SciTech Connect

    Rannenberg, G. C.

    1985-11-19

    An air cycle air conditioning system is provided with regenerative heat exchangers upstream and downstream of an expansion turbine. A closedloop liquid circulatory system serially connects the two regenerative heat exchangers for regeneration without the bulk associated with air-to-air heat exchange. The liquid circulatory system may also provide heat transport to a remote sink heat exchanger and from a remote load as well as heat exchange within the sink heat exchanger and load for enhanced compactness and efficiency.

  13. Highly stable superhydrophobic surfaces under flow conditions

    NASA Astrophysics Data System (ADS)

    Lee, Moonchan; Yim, Changyong; Jeon, Sangmin

    2015-01-01

    We synthesized hydrophobic anodic aluminum oxide nanostructures with pore diameters of 35, 50, 65, and 80 nm directly on quartz crystal microresonators, and the stability of the resulting superhydrophobicity was investigated under flow conditions by measuring changes in the resonance frequency and dissipation factor. When the quartz substrates were immersed in water, their hydrophobic surfaces did not wet due to the presence of an air interlayer. The air interlayer was gradually replaced by water over time, which caused decreases in the resonance frequency (i.e., increases in mass) and increases in the dissipation factor (i.e., increases in viscous damping). Although the water contact angles of the nanostructures increased with increasing pore size, the stability of their superhydrophobicity increased with decreasing pore size under both static conditions (without flow) and dynamic conditions (with flow); this increase can be attributed to an increase in the solid surface area that interacts with the air layer above the nanopores as the pore size decreases. Further, the effects of increasing the flow rate on the stability of the superhydrophobicity were quantitatively determined.

  14. Highly Reducing Partitioning Experiments Relevant to the Planet Mercury

    NASA Technical Reports Server (NTRS)

    Rowland, Rick, II; Vander Kaaden, Kathleen E.; McCubbin, Francis M.; Danielson, Lisa R.

    2017-01-01

    With the data returned from the MErcury Surface Space ENvironment GEochemistry and Ranging (MESSENGER) mission, there are now numerous constraints on the physical and chemical properties of Mercury, including its surface composition. The high S and low FeO contents observed from MESSENGER on the planet's surface suggests a low oxygen fugacity of the present planetary materials. Estimates of the oxygen fugacity for Mercurian magmas are approximately 3-7 log units below the Iron-Wüstite (Fe-FeO) oxygen buffer, several orders of magnitude more reducing than other terrestrial bodies we have data from such as the Earth, Moon, or Mars. Most of our understanding of elemental partitioning behavior comes from observations made on terrestrial rocks, but Mercury's oxygen fugacity is far outside the conditions of those samples. With limited oxygen available, lithophile elements may instead exhibit chalcophile, halophile, or siderophile behaviors. Furthermore, very few natural samples of rocks that formed under reducing conditions are available in our collections (e.g., enstatite chondrites, achondrites, aubrites). With this limited amount of material, we must perform experiments to determine the elemental partitioning behavior of typically lithophile elements as a function of decreasing oxygen fugacity. Experiments are being conducted at 4 GPa in an 880-ton multi-anvil press, at temperatures up to 1850degC. The composition of starting materials for the experiments were selected for the final run products to contain metal, silicate melt, and sulfide melt phases. Oxygen fugacity is controlled in the experiments by adding silicon metal to the samples, using the Si-SiO2 oxygen buffer, which is approximately 5 log units more reducing than the Fe-FeO oxygen buffer at our temperatures of interest. The target silicate melt compositional is diopside (CaMgSi2O6) because measured surface compositions indicate partial melting of a pyroxene-rich mantle. Elements detected on Mercury

  15. The Reduced Effectiveness of EGR to Mitigate Knock at High Loads in Boosted SI Engines

    DOE PAGES

    Szybist, James P.; Wagnon, Scott W.; Splitter, Derek A.; ...

    2017-09-04

    Numerous studies have demonstrated that exhaust gas recirculation (EGR) can attenuate knock propensity in spark ignition (SI) engines at naturally aspirated or lightly boosted conditions. In this paper, we investigate the role of cooled EGR under higher load conditions with multiple fuel compositions, where highly retarded combustion phasing typical of modern SI engines was used. It was found that under these conditions, EGR attenuation of knock is greatly reduced, where EGR doesn’t allow significant combustion phasing advance as it does under lighter load conditions. Detailed combustion analysis shows that when EGR is added, the polytropic coefficient increases causing the compressivemore » pressure and temperature to increase. At sufficiently highly boosted conditions, the increase in polytropic coefficient and additional trapped mass from EGR can sufficiently reduce fuel ignition delay to overcome knock attenuation effects. Kinetic modeling demonstrates that the effectiveness of EGR to mitigate knock is highly dependent on the pressure-temperature condition. Experiments at 2000 rpm have confirmed reduced fuel ignition delay under highly boosted conditions relevant to modern downsized boosted SI engines, where in-cylinder pressure is higher and the temperature is cooler. Finally, at these conditions, charge reactivity increases compared to naturally aspirated conditions, and attenuation of knock by EGR is reduced.« less

  16. Reduced-intensity conditioning allogeneic stem cell transplantation in malignant lymphoma: current status

    PubMed Central

    Zhang, Le; Zhang, Yi-Zhuo

    2013-01-01

    Allogeneic stem cell transplantation (allo-SCT) is a potential cure for patients with malignant lymphoma that is based on the graft-versus-lymphoma (GVL) effect. Myeloablative conditioning allo-SCT is associated with high mortality and morbidity, particularly in patients older than 45 years, heavily pretreated patients (prior hematopoietic stem cell transplantation or more than two lines of conventional chemotherapy) or patients affected by other comorbidities. Therefore, conventional allo-SCT is restricted to younger patients (<50 to 55 years) in good physical condition. Over the last decade, allo-SCT with reduced-intensity conditioning (RIC-allo-SCT) has been increasingly used to treat patients with lymphoma. This treatment is associated with lower toxicity and substantial decrease in the incidence of transplant-related mortality, and has the potential to lead to long-term remissions. Therefore, patients who are not suitable to undergo conventional allo-SCT can benefit from the potentially curative GVL effects of allo-SCT. Although RIC-allo-SCT has improved the survival of lymphoma patients, high post-transplant relapse rates or disease progression mainly results in treatment failure. Thus, further improvement is clearly needed. The role and timing of RIC-allo-SCT in the treatment of lymphoma remains unclear. Therefore, more prospective studies should clarify the effectiveness of this method. In this article, we review the recent literature on RIC-allo-SCT as a treatment for major lymphoma subtypes. Areas that require further investigation in the context of clinical trials are also highlighted. PMID:23691438

  17. Tailoring partially reduced graphene oxide as redox mediator for enhanced biotransformation of iopromide under methanogenic and sulfate-reducing conditions.

    PubMed

    Toral-Sánchez, Eduardo; Rangel-Mendez, J Rene; Ascacio Valdés, Juan A; Aguilar, Cristóbal N; Cervantes, Francisco J

    2016-10-22

    This work reports the first successful application of graphene oxide (GO) and partially reduced GO (rGO) as redox mediator (RM) to increase the biotransformation of the recalcitrant iodinated contrast medium, iopromide (IOP). Results showed that GO-based materials promoted up to 5.5 and 2.8-fold faster biotransformation of IOP by anaerobic sludge under methanogenic and sulfate-reducing conditions, respectively. Correlation between the extent of reduction of GO and its redox-mediating capacity was demonstrated, which was reflected in faster removal and greater extent of biotransformation of IOP. Further analysis indicated that the biotransformation pathway of IOP involved multiple reactions including deiodination, decarboxylation, demethylation, dehydration and N-dealkylation. GO-based materials could be strategically tailored and integrated in biological treatment systems to effectively enhance the redox conversion of recalcitrant pollutants commonly found in wastewater treatment systems and industrial effluents.

  18. Kinetics of DCE and VC mineralization under methanogenic and Fe(III)- reducing conditions

    USGS Publications Warehouse

    Bradley, P.M.; Chapelle, F.H.

    1997-01-01

    The kinetics of anaerobic mineralization of DCE and VC under mathanogenic and Fe(III)-reducing conditions as a function of dissolved contaminant concentration were evaluated. Microorganisms indigenous to creek bed sediments, where groundwater contaminated with chlorinated ethenes continuously discharges, demonstrated significant mineralization of DCE and VC under methanogenic and Fe(III)- reducing conditions. Over 37 days, the recovery of [1,214C]VC radioactivity as 14CO2 ranged from 5% to 44% and from 8% to 100% under methanogenic and Fe(III)-reducing conditions, respectively. The recovery of [1,2-14C]DCE radioactivity as 14CO2 ranged from 4% to 14% and did not vary significantly between methanogenic and Fe(III)reducing conditions. VC mineralization was described by Michaelis- Menten kinetics. Under methanogenic conditions, V(max) was 0.19 ?? 0.01 ??mol L-1 d-1 and the half-saturation constant, k(m), was 7.6 ?? 1.7 ??M. Under Fe(III)-reducing conditions, V(max) was 0.76 ?? 0.07 ??mol L-1 d-1 and k(m) was 1.3 ?? 0.5 ??M. In contrast, DCE mineralization could be described by first-order kinetics. The first-order degradation rate constant for DCE mineralization was 0.6 ?? 0.2% d-1 under methanogenic and Fe(III)-reducing conditions. The results indicate that the kinetics of chlorinated ethane mineralization can vary significantly with the specific contaminant and the predominant redox conditions under which mineralization occurs.

  19. 78 FR 27033 - Safety Zone; High Water Conditions; Illinois River

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-09

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; High Water Conditions; Illinois River... intended to place restrictions on vessels due to current extreme high-water conditions. This safety zone is... History and Information On April 18, 2013, in light of dangerously high water conditions, the Coast...

  20. Stabilization of mercury in sediment by using biochars under reducing conditions.

    PubMed

    Liu, Peng; Ptacek, Carol J; Blowes, David W; Finfrock, Y Zou; Gordon, Robert A

    2017-03-05

    Mercury (Hg) is widely distributed in different localities around the world and poses a serious health threat to humans, especially when ingested in the form of methylmercury (MeHg). Efforts have been directed toward decreasing the production of MeHg by converting Hg to stable forms. Activated carbon and biochar have been evaluated as stabilization agents for Hg in contaminated sediments. However, the long-term fate of Hg stabilized by these materials remains unclear. Here, we compare the effectiveness of Hg stabilization using two biochars prepared from switchgrass at 300°C (lowT) and 600°C (highT). Experiments were conducted by co-blending biochars and sediment for >600 d under anaerobic conditions. Aqueous concentrations of total Hg and MeHg were greatly reduced in the presence of biochars, with the exception of a spike in MeHg concentration observed at ∼440 d in the high-T biochar system. Hg co-occurs with S, Fe, Cu, and other elements within the plant structure of low-T biochar particles, but primarily on the outer surfaces of high-T biochar particles. Our results indicate that the stabilization of Hg may be through an early-stage diagenetic process, suggesting that the stabilization of Hg by biochar may be effective over long time frames.

  1. Delayed extinction fails to reduce skin conductance reactivity to fear-conditioned stimuli.

    PubMed

    Fricchione, Jon; Greenberg, Mark S; Spring, Justin; Wood, Nellie; Mueller-Pfeiffer, Christoph; Milad, Mohammed R; Pitman, Roger K; Orr, Scott P

    2016-09-01

    A brief 10-min time delay between an initial and subsequent exposure to extinction trials has been found to impair memory reconsolidation in fear-conditioned rodents and humans, providing a potential means to reduce fearfulness in anxiety disorders and posttraumatic stress disorder (PTSD). The present study used videos of biologically prepared, conditioned stimuli (tarantulas) to test the efficacy of delayed extinction in blocking reconsolidation of conditioned fear in healthy young adults. Strong differential conditioning, measured by skin conductance, was observed among a screened subset of participants during acquisition. However, the delayed-extinction intervention failed to reduce reactivity to the conditioned stimulus paired with the extinction delay. These results are partially consistent with other recent, mixed findings and point to a need for testing other candidate interventions designed to interfere with the reconsolidation process. © 2016 Society for Psychophysiological Research.

  2. Prereactivation propranolol fails to reduce skin conductance reactivity to prepared fear-conditioned stimuli.

    PubMed

    Spring, Justin D; Wood, Nellie E; Mueller-Pfeiffer, Christoph; Milad, Mohammed R; Pitman, Roger K; Orr, Scott P

    2015-03-01

    Pharmacologic blockade of memory reconsolidation has been demonstrated in fear-conditioned rodents and humans and may provide a means to reduce fearfulness in anxiety disorders and posttraumatic stress disorder. Studying the efficacy of potential interventions in clinical populations is challenging, creating a need for paradigms within which candidate reconsolidation-blocking interventions can be readily tested. We used videos of biologically prepared conditioned stimuli (tarantulas) to test the efficacy of propranolol in blocking reconsolidation of conditioned fear in healthy young adults. Strong differential conditioning, measured by skin conductance, was observed among a screened subset of participants during acquisition. However, subsequent propranolol failed to reduce reactivity to the reactivated conditioned stimulus. These results are consistent with other recent findings and point to a need for testing other candidate drugs. © 2014 Society for Psychophysiological Research.

  3. Effect of hydrothermal reaction time and alkaline conditions on the electrochemical properties of reduced graphene oxide

    NASA Astrophysics Data System (ADS)

    Vermisoglou, E. C.; Giannakopoulou, T.; Romanos, G.; Giannouri, M.; Boukos, N.; Lei, C.; Lekakou, C.; Trapalis, C.

    2015-12-01

    Reduced graphene oxide sheets (rGO) were prepared by hydrothermal treatment of aqueous dispersions of graphite oxide (GtO) applied for short (4 h) and prolonged reaction times (19-24 h). The effect of process duration as well as the alkaline conditions (pH ∼10) by addition of K2CO3 on the quality characteristics of the produced rGO materials was investigated. Both reduction and exfoliation occurred during this process as it was evidenced by FTIR and XRD data. SEM, TEM and HRTEM microscopy displayed highly exfoliated rGO materials. XPS verified that the re-establishment of the conjugated graphene network is more extensive for prolonged times of hydrothermal processing in accordance to Raman spectroscopy measurements. The sample produced under alkaline conditions bore fewer defects and almost 5 times higher BET surface area (∼181 m2/g) than the sample with no pH adjustment (∼34 m2/g) for the same hydrothermal reaction time (19 h), attributed to the developed microporosity. The specific capacitance of this material estimated by electrochemical impedance using three-electrode cell and KCl aqueous solution as an electrolyte was ∼400-500 F/g. When EDLC capacitors were fabricated from rGO materials the electrochemical testing in organic electrolyte i.e. TEABF4 in PC, revealed that the shortest hydrothermal reaction time (4 h) was more efficient resulting in capacitance around 60 F/g.

  4. Changes in Gene Expression of E. coli under Conditions of Modeled Reduced Gravity

    NASA Astrophysics Data System (ADS)

    Vukanti, Raja; Mintz, Eric; Leff, Laura

    2008-06-01

    Relatively few studies have examined bacterial responses to the reduced gravity conditions that are experienced by bacteria grown in space. In this study, whole genome expression of Escherichia coli K12 under clinorotation (which models some of the conditions found under reduced gravity) was analyzed. We hypothesized that phenotypic differences at cellular and population levels under clinorotation (hereafter referred to as modeled reduced gravity) are directly coupled to changes in gene expression. Further, we hypothesized that these responses may be due to indirect effects of these environmental conditions on nutrient accessibility for bacteria. Overall, 430 genes were identified as significantly different between modeled reduced gravity conditions and controls. Up-regulated genes included those involved in the starvation response ( csiD, cspD, ygaF, gabDTP, ygiG, fliY, cysK) and redirecting metabolism under starvation ( ddpX, acs, actP, gdhA); responses to multiple stresses, such as acid stress ( asr, yhiW), osmotic stress ( yehZYW), oxidative stress ( katE, btuDE); biofilm formation ( lldR, lamB, yneA, fadB, ydeY); curli biosynthesis ( csgDEF), and lipid biosynthesis ( yfbEFG). Our results support the previously proposed hypothesis that under conditions of modeled reduced gravity, zones of nutrient depletion develop around bacteria eliciting responses similar to entrance into stationary phase which is generally characterized by expression of starvation inducible genes and genes associated with multiple stress responses.

  5. Adapting wood hydrolysate barriers to high humidity conditions.

    PubMed

    Yaich, Anas Ibn; Edlund, Ulrica; Albertsson, Ann-Christine

    2014-01-16

    The incorporation of layered silicates in bio-based barrier films resulted in lower water vapor permeability, and significantly lowered oxygen permeability at a relative humidity (RH) as high as 80%, with reduced moisture sensitivity of the wood hydrolysate (WH) based films. The applicability of WH based films was accordingly extended over a wider relative humidity condition range. Crude aqueous process liquor, the WH, was extracted from hardwood and utilized as a feed-stock for films without any upgrading pretreatment, yet producing superior oxygen barrier performance compared to partially upgraded WH and highly purified hemicelluloses. Films composed of crude WH and either one of two types of naturally occurring layered silicates, montmorillonite (MMT) or talc, as mineral additives, were evaluated with respect to oxygen and water vapor permeability, morphological, tensile and dynamic thermo-mechanical properties. Films with an oxygen permeability as low as 1.5 (cm(3)μm)/(m(2)daykPa) at 80% RH was achieved.

  6. Reduced body mass gain in small passerines during migratory stopover under simulated heat wave conditions.

    PubMed

    Bauchinger, Ulf; McWilliams, Scott R; Pinshow, Berry

    2011-04-01

    For birds that migrate long distances, maximizing the rate of refueling at stopovers is advantageous, but ambient conditions may adversely influence this vital process. We simulated a 3-day migratory stopover for garden warblers (Sylvia borin) and compared body temperatures (T(b)) and rates of refueling under conditions of a heat wave (T(a)=40 °C by day, and 15 °C at night) with those under more moderate conditions (T(a)=27 °C by day, and 15 °C at night). We measured T(b) with implanted thermo-sensitive radio transmitters. Birds had significantly lower rates of body mass gain on the first day of stopover (repeated measures mixed model ANOVA, p=0.002) affecting body mass during the entire stopover (p=0.034) and higher maximum T(b) during the day when exposed to high T(a) than when exposed to moderate T(a) (p=0.002). In addition, the birds exposed to high T(a) by day had significantly lower minimum T(b) at night than those exposed to moderate daytime T(a) (p=0.048), even though T(a) at night was the same for both groups. We interpret this lower nighttime T(b) to be a means of saving energy to compensate for elevated daytime thermoregulatory requirements, while higher T(b) by day may reduce protein turnover. All effects on T(b) were significantly more pronounced during the first day of stopover than on days two and three, which may be linked to the rate of renewal of digestive function during stopover. Our results suggest that environmental factors, such as high T(a), constrain migratory body mass gain. Extreme high T(a) and heat waves are predicted to increase due to global climate change, and thus are likely to pose increasing constraints on regaining body mass during stopover and therefore migratory performance in migratory birds. Copyright © 2010 Elsevier Inc. All rights reserved.

  7. Floral resource limitation severely reduces butterfly survival, condition and flight activity in simplified agricultural landscapes.

    PubMed

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-02-01

    Agricultural intensification has a strong negative impact on farmland biodiversity (including flower-visiting insects), but understanding the mechanisms involved in this requires experimental work. We document the impact of nectar limitation on the performance of a flower-visiting insect, the meadow brown butterfly Maniola jurtina. We conducted two types of experiments: a field experiment in agricultural landscapes with grasslands of different management intensity and an experiment in outdoor flight cages in which the nectar supply was simulated. For the field experiment, we introduced an array of nectar resources in intensively managed, nectar-poor meadows and in extensively managed, flower-rich grasslands and counted flower visitors. Despite higher butterfly abundance in the extensive meadows, our introduced nectar sources were more frequently visited in intensive meadows, indicating the lack of floral resources. The 48-h confinement under nectar-poor conditions in the flight cages had a strong negative effect on body condition, flight activity and lifetime survival compared to butterflies under nectar-rich conditions. Female lifespan was reduced by 22% and male lifespan even by 43%. Agricultural landscapes that provide limited amounts of floral nectar, and no high-quality, preferred nectar sources relative to the needs of the flower-visiting species, may create ecological sinks. Regards an insect's performance, the simple presence of nectar is not necessarily functionally adequate. The effectiveness of agri-environmental schemes for flower-visiting insects (e.g. flower strips) could be improved based on ecological and evolutionary insights on the effects of specific nectar quantities and qualities.

  8. Anaerobic hydrocarbon degradation in petroleum-contaminated harbor sediments under sulfate-reducing and artificially imposed iron-reducing conditions

    USGS Publications Warehouse

    Coates, J.D.; Anderson, R.T.; Woodward, J.C.; Phillips, E.J.P.; Lovley, D.R.

    1996-01-01

    The potential use of iron(III) oxide to stimulate in-situ hydrocarbon degradation in anaerobic petroleum-contaminated harbor sediments was investigated. Previous studies have indicated that Fe(III)-reducing bacteria (FeRB) can oxidize some electron donors more effectively than sulfate- reducing bacteria (SRB). In contrast to previous results in freshwater sediments, the addition of Fe(III) to marine sediments from San Diego Bay, CA did not switch the terminal electron-accepting process (TEAP) from sulfate reduction to Fe-(III) reduction. Addition of Fe(III) also did not stimulate anaerobic hydrocarbon oxidation. Exposure of the sediment to air [to reoxidize Fe(II) to Fe(III)] followed by anaerobic incubation of the sediments, resulted in Fe-(III) reduction as the TEAP, but contaminant degradation was not stimulated and in some instances was inhibited. The difference in the ability of FeRB to compete with the SRB in the different sediment treatments was related to relative population sizes. Although the addition of Fe(III) did not stimulate hydrocarbon degradation, the results presented here as well as other recent studies demonstrate that there may be significant anaerobic hydrocarbon degradation under sulfate-reducing conditions in harbor sediments.

  9. Larval competition reduces body condition in the female seed beetle, Callosobruchus maculatus.

    PubMed

    Schade, Daynika J; Vamosi, Steven M

    2012-01-01

    Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles.

  10. Reducing recidivism and symptoms in emerging adults with serious mental health conditions and justice system involvement.

    PubMed

    Davis, Maryann; Sheidow, Ashli J; McCart, Michael R

    2015-04-01

    The peak years of offending in the general population and among those with serious mental health conditions (SMHC) are during emerging adulthood. There currently are no evidence-based interventions for reducing offending behavior among 18-21 year olds, with or without SMHC. This open trial examined outcomes from an adaptation of Multisystemic Therapy (MST), an effective juvenile recidivism reduction intervention, modified for use with emerging adults with SMHC and recent justice system involvement. MST for emerging adults (MST-EA) targets MH symptoms, recidivism, problem substance use, and young adult functional capacities. All study participants (n = 41) were aged 17-20 and had a MH diagnosis and recent arrest or incarceration. Implementation outcomes indicated that MST-EA was delivered with strong fidelity, client satisfaction was high, and the majority of participants successfully completed the intervention. Research retention rates also were high. Pre-post-analyses revealed significant reductions in participants' MH symptoms, justice system involvement, and associations with antisocial peers.

  11. Reducing Recidivism and Symptoms in Emerging Adults with Serious Mental Health Conditions and Justice System Involvement

    PubMed Central

    Davis, Maryann; Sheidow, Ashli J.; McCart, Michael R.

    2014-01-01

    The peak years of offending in the general population and among those with serious mental health conditions (SMHC) are during emerging adulthood. There currently are no evidence-based interventions for reducing offending behavior among 18–21 year olds, with or without SMHC. This open trial examined outcomes from an adaptation of Multisystemic Therapy (MST), an effective juvenile recidivism reduction intervention, modified for use with emerging adults with SMHC and recent justice system involvement. MST for emerging adults (MST-EA) targets MH symptoms, recidivism, problem substance use, and young adult functional capacities. All study participants (n=41) were aged 17–20 and had a MH diagnosis and recent arrest or incarceration. Implementation outcomes indicated that MST-EA was delivered with strong fidelity, client satisfaction was high, and the majority of participants successfully completed the intervention. Research retention rates also were high. Pre-post analyses revealed significant reductions in participants’ MH symptoms, justice-system involvement, and associations with antisocial peers. PMID:25023764

  12. Maintaining reduced noise levels in a resource-constrained neonatal intensive care unit by operant conditioning.

    PubMed

    Ramesh, A; Denzil, S B; Linda, R; Josephine, P K; Nagapoornima, M; Suman Rao, P N; Swarna Rekha, A

    2013-03-01

    To evaluate the efficacy of operant conditioning in sustaining reduced noise levels in the neonatal intensive care unit (NICU). Quasi-experimental study on quality of care. Level III NICU of a teaching hospital in south India. 26 staff employed in the NICU. (7 Doctors, 13 Nursing staff and 6 Nursing assistants). Operant conditioning of staff activity for 6 months. This method involves positive and negative reinforcement to condition the staff to modify noise generating activities. Comparing noise levels in decibel: A weighted [dB (A)] before conditioning with levels at 18 and 24 months after conditioning. Decibel: A weighted accounts for noise that is audible to human ears. Operant conditioning for 6 months sustains the reduced noise levels to within 62 dB in ventilator room 95% CI: 60.4 - 62.2 and isolation room (95% CI: 55.8 - 61.5). In the preterm room, noise can be maintained within 52 dB (95% CI: 50.8 - 52.6). This effect is statistically significant in all the rooms at 18 months (P = 0.001). At 24 months post conditioning there is a significant rebound of noise levels by 8.6, 6.7 and 9.9 dB in the ventilator, isolation and preterm room, respectively (P =0.001). Operant conditioning for 6 months was effective in sustaining reduced noise levels. At 18 months post conditioning, the noise levels were maintained within 62 dB (A), 60 dB (A) and 52 dB (A) in the ventilator, isolation and pre-term room, respectively. Conditioning needs to be repeated at 12 months in the ventilator room and at 18 months in the other rooms.

  13. Fracture modes in tubular LSFCO ceramic membranes under graded reducing conditions

    SciTech Connect

    Nagendra, N.; Biswas, S.; Nithyanantham, T.; Bandopadhyay, S.

    2013-06-01

    Highlights: ► Microstructural evolution in LSFCO membranes under graded environment is reported. ► The role of chemically induced stresses and oxygen deficiency is evaluated. ► The stress distribution is modeled by a point defect model. - Abstract: Chromium (III) oxide (Cr{sub 2}O{sub 3})-doped LaSrFeO{sub 3} perovskite, La{sub 0.2}Sr{sub 0.8}Fe{sub 0.8}Cr{sub 0.2}O{sub 3−δ} (LSFCO), is being considered as a potential material for applications in solid oxide fuel cells, gas separation membranes, and electrochemical reactors because of its high electro-catalytic activity. Similar to other perovskites, the performance and mechanical strength of LSFCO materials are significantly affected by environment and temperature. Here, we report a fracture gradient phenomenon in tubular C-ring-shaped LSFCO ceramic membranes under graded reducing conditions. The graded reducing condition was produced by flushing N{sub 2} on the outer side of the C-ring membranes at 1000 °C while keeping the inner side untreated. The rings were then diametrically compressed to fracture, and the resultant fracture morphology was analyzed with a scanning electron microscope (SEM). A fracture gradient with three distinct regions across the thickness of the membranes was identified on the split surfaces. In the outer region of the C-ring specimen exposed to N{sub 2}, a mixed inter/transgranular fracture with a predominant intergranular pattern was observed. In the middle section of the fracture surface, a characteristic transgranular fracture of the perovskite grains was found. At the inner region of the ring, a mixed inter/transgranular fracture with a predominant transgranular pattern occurred. The mechanism of gradient fractures was attributed both to chemically induced stresses caused by oxygen diffusion and to the formation of a separate phase of oxygen-deficient perovskite in the parent perovskite. The stresses generated were modeled by a point defect model. This work provides

  14. Apparatus having reduced mechanical forces for supporting high magnetic fields

    DOEpatents

    Prueitt, Melvin L.; Mueller, Fred M.; Smith, James L.

    1991-01-01

    The present invention identifies several configurations of conducting elements capable of supporting extremely high magnetic fields suitable for plasma confinement, wherein forces experienced by the conducting elements are significantly reduced over those which are present as a result of the generation of such high fields by conventional techniques. It is anticipated that the use of superconducting materials will both permit the attainment of such high fields and further permit such fields to be generated with vastly improved efficiency.

  15. Manganese oxide-coated redox bars as an indicator for reducing soil conditions

    NASA Astrophysics Data System (ADS)

    Dorau, Kristof; Mansfeldt, Tim

    2014-05-01

    Field identification of reducing soil conditions is of concern not only for soil pedogenesis but also for nutrient and pollutant dynamics in soils. We manufactured manganese (Mn) oxide-coated polyvinyl chloride (PVC) bars and proved their suitability for identification of reducing soil conditions in both the laboratory and field. Birnessite (δ-MnO2) was synthesized according to a recently published method and was coated onto white PVC bars. We used microcosm devices with adjusted redox potentials (EH) to distinguish the onset and intensity of depletion patterns along the Mn oxide-coating and soil column experiments combined with field application to validate the enhanced removal of Mn against Fe oxide-coated bars under anaerobe soil conditions. Field application was performed at a site with shallow and strongly fluctuating water tables where water table depth and soil temperature were monitored. Three microcosm experiments adjusted to oxidizing (EH ~500 mV, pH 7), weakly reducing (EH ~175 mV, pH 7) and moderately reducing conditions (EH ~25 mV, pH 7) showed depending on the EH no, slight, or intense removal of the Mn oxide-coating, respectively. Moreover, the removal of Mn oxide (225 mm2 d-1) in soil column experiments exceeded the removal of Fe oxide (118 mm2 d-1). The enhanced removal of the Mn oxide-coating was also found under anaerobe conditions in field application. Consequently, identifying of reducing conditions in soils by Mn oxide-coated bars is possible. We recommend using this methodology for short-term monitoring, e.g. on weekly basis, since tri- and tetravalent Mn is the preferred electron acceptor compared with trivalent Fe.

  16. Tibial Acceleration and Spatiotemporal Mechanics in Distance Runners During Reduced-Body-Weight Conditions.

    PubMed

    Moran, Matthew F; Rickert, Brendan J; Greer, Beau K

    2017-05-01

    Treadmills that unload runners via a differential air-pressure (DAP) bladder (eg, AlterG Anti-Gravity Treadmill) are commonly used to reduce effective body weight (BW) in a clinical setting. However, the relationship between the level of unloading and tibial stress is currently unknown. To determine the relationship between tibial impact acceleration and level of BW unloading during running. Cross-sectional. University motion-analysis laboratory. 15 distance runners (9 male, 6 female; 20.4 ± 2.4 y, 60.1 ± 12.6 kg). Peak tibial acceleration and peak-to-peak tibial acceleration were measured via a uniaxial accelerometer attached to the tibia during a 37-min continuous treadmill run that simulated reduced-BW conditions via a DAP bladder. The trial began with a 10-min run at 100% BW followed by nine 3-min stages where BW was systematically reduced from 95% to 60% in 5% increments. There was no significant relationship between level of BW and either peak tibial acceleration or peak-to-peak tibial acceleration (P > .05). Both heart rate and step rate were significantly reduced with each 5% reduction in BW level (P < .01). Although ground-reaction forces are reduced when running in reduced-BW conditions on a DAP treadmill, tibial shock magnitudes are unchanged as an alteration in spatiotemporal running mechanics (eg, reduced step rate) and may nullify the unloading effect.

  17. The reduced density matrix method and the role of three-index representability conditions

    NASA Astrophysics Data System (ADS)

    Braams, Bastiaan J.; Zhao, Zhengji; Fukuda, Mituhiro; Overton, Michael L.; Percus, Jerome K.

    2004-03-01

    The variational approach for electronic structure based on the two-body reduced density matrix is studied, incorporating two representability conditions beyond the previously used P, Q and G conditions. The additional conditions (called T1 and T2 here) are implicit in work of R. M. Erdahl and extend the well-known three-index diagonal conditions also known as the Weinhold-Wilson inequalities. Calculations of the ground state energy and the dipole moment are reported for 47 different systems, in each case using an STO-6G basis set and comparing with Hartree-Fock, SDCI, BD(T), CCSD(T) and full CI calculations [2]. It is found that the use of the T1 and T2 conditions gives a significant improvement over just the P, Q and G conditions, and provides in all cases that we have studied more accurate results than the other mentioned approximations. [1] R. M. Erdahl, Int. J. Quantum Chem. 13, 697--718 (1978). [2] Zhengji Zhao, Bastiaan J. Braams, Mituhiro Fukuda, Michael L. Overton and Jerome K. Percus: "The reduced density matrix method and the role of three-index representability conditions". Accepted for publication in Journal of Chemical Physics.

  18. 38 CFR 21.9675 - Conditions that result in reduced rates or no payment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Conditions that result in reduced rates or no payment. 21.9675 Section 21.9675 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Post-9/11 GI Bill Payments-Educational...

  19. Reducing the Negative Impact of Adverse Environmental Conditions on Elementary-Aged Children and Their Families.

    ERIC Educational Resources Information Center

    Wilson, Cindy

    A practicum strategy was designed and implemented that focused on reducing the negative impact of adverse environmental conditions in one particular neighborhood in a town in Alberta (Canada) with a population of 8,500. Children in this neighborhood were served by one elementary school (enrollment 383), from which the strategy was implemented. The…

  20. 38 CFR 21.9675 - Conditions that result in reduced rates or no payment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2013-07-01 2013-07-01 false Conditions that result in reduced rates or no payment. 21.9675 Section 21.9675 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Post-9/11 GI Bill...

  1. 38 CFR 21.9675 - Conditions that result in reduced rates or no payment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2014-07-01 2014-07-01 false Conditions that result in reduced rates or no payment. 21.9675 Section 21.9675 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Post-9/11 GI Bill...

  2. 38 CFR 21.9675 - Conditions that result in reduced rates or no payment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2011-07-01 2011-07-01 false Conditions that result in reduced rates or no payment. 21.9675 Section 21.9675 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Post-9/11 GI Bill...

  3. 38 CFR 21.9675 - Conditions that result in reduced rates or no payment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2012-07-01 2012-07-01 false Conditions that result in reduced rates or no payment. 21.9675 Section 21.9675 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS (CONTINUED) VOCATIONAL REHABILITATION AND EDUCATION Post-9/11 GI Bill...

  4. Anaerobic Biodegradation of soybean biodiesel and diesel blends under sulfate-reducing conditions

    EPA Science Inventory

    Biotransformation of soybean biodiesel and its biodiesel/petrodiesel blends were investigated under sulfate-reducing conditions. Three blends of biodiesel, B100, B50, and B0, were treated using microbial cultures pre-acclimated to B100 (biodiesel only) and B80 (80% biodiesel and ...

  5. Apparatus for storing high magnetic fields having reduced mechanical forces and reduced magnetic pollution

    DOEpatents

    Prueitt, Melvin L.; Mueller, Fred M.; Smith, James L.

    1991-01-01

    The present invention identifies several configurations of conducting elements capable of storing extremely high magnetic fields for the purpose of energy storage or for other uses, wherein forces experienced by the conducting elements and the magnetic field pollution produced at locations away from the configuration are both significantly reduced over those which are present as a result of the generation of such high fields by currently proposed techniques. It is anticipated that the use of superconducting materials will both permit the attainment of such high fields and further permit such fields to be generated with vastly improved efficiency.

  6. Apparatus for storing high magnetic fields having reduced mechanical forces and reduced magnetic pollution

    DOEpatents

    Prueitt, M.L.; Mueller, F.M.; Smith, J.L.

    1991-04-09

    The present invention identifies several configurations of conducting elements capable of storing extremely high magnetic fields for the purpose of energy storage or for other uses, wherein forces experienced by the conducting elements and the magnetic field pollution produced at locations away from the configuration are both significantly reduced over those which are present as a result of the generation of such high fields by currently proposed techniques. It is anticipated that the use of superconducting materials will both permit the attainment of such high fields and further permit such fields to be generated with vastly improved efficiency. 15 figures.

  7. An integrated condition-monitoring method for a milling process using reduced decomposition features

    NASA Astrophysics Data System (ADS)

    Liu, Jie; Wu, Bo; Wang, Yan; Hu, Youmin

    2017-08-01

    Complex and non-stationary cutting chatter affects productivity and quality in the milling process. Developing an effective condition-monitoring approach is critical to accurately identify cutting chatter. In this paper, an integrated condition-monitoring method is proposed, where reduced features are used to efficiently recognize and classify machine states in the milling process. In the proposed method, vibration signals are decomposed into multiple modes with variational mode decomposition, and Shannon power spectral entropy is calculated to extract features from the decomposed signals. Principal component analysis is adopted to reduce feature size and computational cost. With the extracted feature information, the probabilistic neural network model is used to recognize and classify the machine states, including stable, transition, and chatter states. Experimental studies are conducted, and results show that the proposed method can effectively detect cutting chatter during different milling operation conditions. This monitoring method is also efficient enough to satisfy fast machine state recognition and classification.

  8. The effects of sugar phosphates in reducing hif-1? Under hypoxic conditions.

    PubMed

    Tucci, Michelle; Perrett, Wesley; Scott, Victoria; Wilson, Gerri; Black, David; Benghuzzi, Hamed

    2012-01-01

    Preliminary research has shown evidence of the presence of connective tissue growth factor CTGF in the tenosynovium of patients with carpal tunnel syndrome, a finding which supports the fibrotic pathophysiological progression of the disease. Connective tissue growth factor (CTGF) expression is regulated through the actions of two distinct molecular signals; transforming growth factor-beta (TGF-ß) and hypoxia inducible factor-1 alpha (HIF-1a). Mannose-6 phosphate is a natural inhibitor of TGF-ß and can also is converted to fructose 6 phosphate which we have shown is capable of reducing HIF-1 a. The goal of this experiment was to determine if mannose 6 phosphate is capable of reducing HIF-1a reducing both components of the CTGF pathway. Fibroblast cells were subjected to 5µM or 50µM concentration of either fructose 1,6 diphosphate (F6P) or mannose 6 phosphate (M6P) for a period of 24 hours in either ambient or hypoxic conditions. After the incubation period, cell viability, cell damage, morphology, and concentration of HIF-1a were determined. Cell numbers were reduced by approximately 50% in hypoxic conditions compared with ambient control. Intracellular glutathione concentration was increased significantly under hypoxic conditions compared with control. The concentration of reduced glutathione in both F6P and M6P were similar to ambient air values indicating a protection against oxidative stress. Hypoxia inducible factor-1 alpha was increased in cells under hypoxic conditions compared to base line levels in normoxic treated cells. Interestingly, only 5µM F6P was able to reduce HIF-1a back toward control normoxic values. The data suggest that the HIF-1a pathway leading to fibrosis is not the primary pathway for reductions in CTGF following MP6 treatments. This information is important in terms of developing compounds which decrease adhesion while not decreasing cell viability or impairing cellular function.

  9. Soil structure, colloids, and chemical transport as affected by short-term reducing conditions: a laboratory study

    NASA Astrophysics Data System (ADS)

    de-Campos, A. B.; Mamedov, A. I.; Huang, C.; Wagner, L. E.

    2008-12-01

    Upland soils in the Midwestern US often undergo reducing conditions when soils are temporally flooded during the spring and remain water saturated for days or weeks. Short-term reducing conditions change the chemistry of the soil and may affect soil structure and solution chemical transport. The effects of short-term reducing conditions on chemical and physical properties of the soils, colloids, and associated chemical/nutrients transport are still not well understood and was the objective of our study. A biogeochemical reactor was built to achieve reducing conditions. Three cultivated and three uncultivated soils with different organic carbon contents were incubated in the reactor for 1 hour and 3 days under anaerobic conditions. Effects of the redox state on soil structure (pore size distribution) and drainable porosity, colloids mobility, and chemical transport were determined using high energy moisture characteristic and analytical methods. After each treatment, the soil solution was collected for redox potential (Eh), pH, and electrical conductivity (EC) measurements, and chemical analysis of metals (Ca, Mg, K), nutrients (N, P), and dissolved organic carbon. Strongly reducing conditions were achieved after 3 days of incubation and were followed by a decrease in soil porosity and an increase in pH, EC, clay dispersion, swelling, colloids mobility, and associated chemical transport. The trend for each soil depended on their initial structural stability and chemical properties. The structure of cultivated soils and the leaching of nutrients and carbon from uncultivated soils were more sensitive to the redox state. A strong correlation was found between changes in Eh and drainable porosity. The role of short-term reducing conditions on changes in redox sensitive elements, organic matter decomposition, pH, and EC and their influence on soil structure and soil particles or colloids/chemical transport for both soil groups are discussed in the paper. This study

  10. Hydrocarbon activation under sulfate-reducing and methanogenic conditions proceeds by different mechanisms.

    NASA Astrophysics Data System (ADS)

    Head, Ian; Gray, Neil; Aitken, Caroline; Sherry, Angela; Jones, Martin; Larter, Stephen

    2010-05-01

    Microbial degradation of alkanes typically involves their conversion to fatty acids which are then catabolised by beta-oxidation. The critical step in this process is activation of the hydrocarbon. Under oxic conditions this is catalyzed by monooxygenase enzymes with the formation of long chain alcohols. In the absence of oxygen alternative alkane activation mechanisms have been observed or proposed. Fumarate addition to alkanes to form alkyl succinates is considered a central process in anaerobic hydrocarbon degradation. Comparative studies of crude oil degradation under sulphate-reducing and methanogenic conditions revealed distinctive patterns of compound class removal and metabolite formation. Alkyl succinates derived from C7 to C26 n-alkanes and branched chain alkanes were found in abundance in sulfate-reducing systems but these were not detected during methanogenic crude oil degradation. Only one other mechanism of alkane activation has been elucidated to date. This involves addition of carbon derived from bicarbonate/CO2 to C-3 of an alkane chain to form a 2-ethylalkane with subsequent removal of the ethyl group leading to the formation of a fatty acid 1 carbon shorter than the original alkane. 2-ethylalkanes have never been detected as metabolites of anaerobic alkane degradation and were not detected in crude oil-degrading methanogenic systems. Due to the range of alkanes present in crude oil it was not possible to infer the generation of C-odd acids from C-even alkanes which is characteristic of the C-3 carboxylation mechanism. Furthermore genes homologous to alkysuccinate synthetases were not detected in the methanogenic hydrocarbon degrading community by pyrosequencing of total DNA extracted from methanogenic enrichments cultures. beta-oxidation genes were detected and intriguingly, alcohol and aldehyde dehydrogenase genes were present. This offers the possibility that alkane activation in the methanogenic system does not proceed via acid metabolites

  11. Conditional High-Order Boltzmann Machines for Supervised Relation Learning.

    PubMed

    Huang, Yan; Wang, Wei; Wang, Liang; Tan, Tieniu

    2017-09-01

    Relation learning is a fundamental problem in many vision tasks. Recently, high-order Boltzmann machine and its variants have shown their great potentials in learning various types of data relation in a range of tasks. But most of these models are learned in an unsupervised way, i.e., without using relation class labels, which are not very discriminative for some challenging tasks, e.g., face verification. In this paper, with the goal to perform supervised relation learning, we introduce relation class labels into conventional high-order multiplicative interactions with pairwise input samples, and propose a conditional high-order Boltzmann Machine (CHBM), which can learn to classify the data relation in a binary classification way. To be able to deal with more complex data relation, we develop two improved variants of CHBM: 1) latent CHBM, which jointly performs relation feature learning and classification, by using a set of latent variables to block the pathway from pairwise input samples to output relation labels and 2) gated CHBM, which untangles factors of variation in data relation, by exploiting a set of latent variables to multiplicatively gate the classification of CHBM. To reduce the large number of model parameters generated by the multiplicative interactions, we approximately factorize high-order parameter tensors into multiple matrices. Then, we develop efficient supervised learning algorithms, by first pretraining the models using joint likelihood to provide good parameter initialization, and then finetuning them using conditional likelihood to enhance the discriminant ability. We apply the proposed models to a series of tasks including invariant recognition, face verification, and action similarity labeling. Experimental results demonstrate that by exploiting supervised relation labels, our models can greatly improve the performance.

  12. Magnesium deficiency reduces fear-induced conditional lick suppression in mice.

    PubMed

    Bardgett, Mark E; Schultheis, Patrick J; Muzny, Ashley; Riddle, Michael D; Wagge, Jordan R

    2007-03-01

    The consequences of broad-scale alterations in magnesium (Mg2+) levels on learning and memory are poorly understood. We have recently demonstrated that adult male mice maintained on an Mg2+-deficient diet exhibit reduced conditional freezing behavior. The purpose of the present study was to determine if the detrimental effect of Mg2+ deficiency in mice extended to another measure of conditional fear, conditioned lick suppression (CLS), as well as to another form of learning, spatial learning in the swim maze task. Adult male C57Bl/6J mice were provided with a normal or Mg2+-deficient diet and were trained and tested ten days later for conditional fear, using CLS and freezing as indicators of learning. Learning in the swim maze was tested in a separate cohort of mice during days 14-18 of diet exposure. Mg2+-deficient mice showed reduced CLS as well as conditional freezing behavior in comparison to control mice. However, learning in the swim maze task was normal in Mg2+-deficient mice. These studies indicate that the detrimental effects of Mg2+ deficiency extend to other measures of conditional fear but not to all forms of learning.

  13. Reduced Order Modeling For High Speed Flows with Moving Shocks

    DTIC Science & Technology

    2001-12-03

    use of Proper Orthogonal Decomposition ( POD ) for reduced order modeling (ROM)of fluid problems is extended to high-speed compressible fluid flows. The...challenge in using POD for high-speed flows is presented by the presence of moving discontinuities in the flow field. To ovecome these difficulties...difficulty. The accuracy and order reduction of the domain decomposition POD /ROM approach is quantified for each application. ROMs with as large as three

  14. High-Stakes Testing: Can Rapid Assessment Reduce the Pressure?

    ERIC Educational Resources Information Center

    Yeh, Stuart S.

    2006-01-01

    This article presents findings about the implementation of a system for rapidly assessing student progress in math and reading in grades K-12--a system that potentially could reduce pressure on teachers resulting from high-stakes testing and the implementation of the No Child Left Behind Act. Interviews with 49 teachers and administrators in one…

  15. Reducing peanut allergens by high pressure combined with polyphenol oxidase

    USDA-ARS?s Scientific Manuscript database

    Polyphenol oxidase (PPO) has been shown to reduce major peanut allergens (Ara h 1 and Ara h 2). Because high pressure (HP) can increase enzyme activity, we postulated that further reduction of peanut allergens can be achieved through HP combined with PPO. Peanut extracts were treated with each of th...

  16. A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

    NASA Technical Reports Server (NTRS)

    Williams, R. J.

    1986-01-01

    The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or floatation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacites with small quantities of gas which are recirculated over the sample is described. This system should be adaptable to reduced gravity space experiments requiring redox control. Experiments done conventionally and those done using this technique yield identical results done in a 1-g field.

  17. A system for conducting igneous petrology experiments under controlled redox conditions in reduced gravity

    NASA Technical Reports Server (NTRS)

    Williams, Richard J.

    1987-01-01

    The Space Shuttle and the planned Space Station will permit experimentation under conditions of reduced gravitational acceleration offering experimental petrologists the opportunity to study crystal growth, element distribution, and phase chemistry. In particular the confounding effects of macro and micro scale buoyancy-induced convection and crystal settling or flotation can be greatly reduced over those observed in experiments in the terrestrial laboratory. Also, for experiments in which detailed replication of the environment is important, the access to reduced gravity will permit a more complete simulation of processes that may have occurred on asteroids or in free space. A technique that was developed to control, measure, and manipulate oxygen fugacities with small quantities of gas which are recirculated over the sample. This system could be adaptable to reduced gravity space experiments requiring redox control.

  18. Dietary fibers reduce food intake by satiation without conditioned taste aversion in mice.

    PubMed

    Rasoamanana, Rojo; Even, Patrick C; Darcel, Nicolas; Tomé, Daniel; Fromentin, Gilles

    2013-02-17

    It is well known that intake of dietary fiber (DF) potently decreases food intake and feelings of hunger and/or promotes satiety ratings. However, the mechanisms explaining these effects are not well characterized. This work was performed to determine which of satiation and/or satiety mechanisms provoke the decrease of food intake induced by DF in mice. We tested in an intra-group protocol a low-viscosity (LV, fructo-oligosaccharide), a viscous (VP, guar gum) and a high-viscosity (HV, mixture of guar gum and fructo-oligosaccharide) preload. These were given to mice by intra-gastric gavage. It appeared that viscous preloads such as VP and HV reduced the daily energy intake by 14% and 21% respectively. The strong effect of HV was mainly due to a large decrease of meal size (by 57%) and meal duration (by 65%) with no effect on ingestion rate during the first 30 min after administration. Therefore, the DF-induced decrease of energy intake was due to a satiation mechanism. This is further supported by a 3-fold increased sensitization of neurons in the nucleus of the solitary tract as observed by c-Fos protein immunolabelling. No compensation of food intake was observed during the rest of the day, a phenomenon that may be explained by the fact that metabolic rate remained high despite the lower food intake. We have also shown that the DF-induced inhibition of food intake was not paired with a conditioned taste aversion. To conclude, this work demonstrates that DF inhibits food intake by increasing satiation during ~1h after administration.

  19. Pharmacological depletion of serotonin in the basolateral amygdala complex reduces anxiety and disrupts fear conditioning.

    PubMed

    Johnson, Philip L; Molosh, Andrei; Fitz, Stephanie D; Arendt, Dave; Deehan, Gerald A; Federici, Lauren M; Bernabe, Cristian; Engleman, Eric A; Rodd, Zachary A; Lowry, Christopher A; Shekhar, Anantha

    2015-11-01

    The basolateral and lateral amygdala nuclei complex (BLC) is implicated in a number of emotional responses including conditioned fear and social anxiety. Based on previous studies demonstrating that enhanced serotonin release in the BLC leads to increased anxiety and fear responses, we hypothesized that pharmacologically depleting serotonin in the BLC using 5,7-dihydroxytryptamine (5,7-DHT) injections would lead to diminished anxiety and disrupted fear conditioning. To test this hypothesis, 5,7-DHT(a serotonin-depleting agent) was bilaterally injected into the BLC. Desipramine (a norepinephrine reuptake inhibitor) was systemically administered to prevent non-selective effects on norepinephrine. After 5days, 5-7-DHT-treated rats showed increases in the duration of social interaction (SI) time, suggestive of reduced anxiety-like behavior. We then used a cue-induced fear conditioning protocol with shock as the unconditioned stimulus and tone as the conditioned stimulus for rats pretreated with bilateral 5,7-DHT, or vehicle, injections into the BLC. Compared to vehicle-treated rats, 5,7-DHT rats had reduced acquisition of fear during conditioning (measured by freezing time during tone), also had reduced fear retrieval/recall on subsequent testing days. Ex vivo analyses revealed that 5,7-DHT reduced local 5-HT concentrations in the BLC by ~40% without altering local norepinephrine or dopamine concentrations. These data provide additional support for 5-HT playing a critical role in modulating anxiety-like behavior and fear-associated memories through its actions within the BLC. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Pharmacological depletion of serotonin in the basolateral amygdala complex reduces anxiety and disrupts fear conditioning

    PubMed Central

    Johnson, Philip L.; Molosh, Andrei; Fitz, Stephanie D.; Arendt, Dave; Deehan, Gerald A.; Federici, Lauren M.; Bernabe, Cristian; Engleman, Eric A.; Rodd, Zachary A.; Lowry, Christopher A.; Shekhar, Anantha

    2015-01-01

    The basolateral and lateral amygdala nuclei complex (BLC) is implicated in a number of emotional responses including conditioned fear and social anxiety. Based on previous studies demonstrating that enhanced serotonin release in the BLC leads to increased anxiety and fear responses, we hypothesized that pharmacologically depleting serotonin in the BLC using 5,7-dihydroxytryptamine (5,7-DHT) injections would lead to diminished anxiety and disrupted fear conditioning. To test this hypothesis, 5,7-DHT (a serotonin-depleting agent) was bilaterally injected into the BLC. Desipramine (a norepinephrine reuptake inhibitor) was systemically administered to prevent non-selective effects on norepinephrine. After 5 days, 5-7-DHT-treated rats showed increases in the duration of social interaction (SI) time, suggestive of reduced anxiety-like behavior. We then used a cue-induced fear conditioning protocol with shock as the unconditioned stimulus and tone as the conditioned stimulus for rats pretreated with bilateral 5,7-DHT, or vehicle, injections into the BLC. Compared to vehicle-treated rats, 5,7-DHT rats had reduced acquisition of fear during conditioning (measured by freezing time during tone), also had reduced fear retrieval/recall on subsequent testing days. Ex vivo analyses revealed that 5,7-DHT reduced local 5-HT concentrations in the BLC by ∼40% without altering local norepinephrine or dopamine concentrations. These data provide additional support for 5-HT playing a critical role in modulating anxiety-like behavior and fear-associated memories through its actions within the BLC. PMID:26476009

  1. Decoupling of arsenic and iron release from ferrihydrite suspension under reducing conditions: a biogeochemical model

    PubMed Central

    Burnol, André; Garrido, Francis; Baranger, Philippe; Joulian, Catherine; Dictor, Marie-Christine; Bodénan, Françoise; Morin, Guillaume; Charlet, Laurent

    2007-01-01

    High levels of arsenic in groundwater and drinking water are a major health problem. Although the processes controlling the release of As are still not well known, the reductive dissolution of As-rich Fe oxyhydroxides has so far been a favorite hypothesis. Decoupling between arsenic and iron redox transformations has been experimentally demonstrated, but not quantitatively interpreted. Here, we report on incubation batch experiments run with As(V) sorbed on, or co-precipitated with, 2-line ferrihydrite. The biotic and abiotic processes of As release were investigated by using wet chemistry, X-ray diffraction, X-ray absorption and genomic techniques. The incubation experiments were carried out with a phosphate-rich growth medium and a community of Fe(III)-reducing bacteria under strict anoxic conditions for two months. During the first month, the release of Fe(II) in the aqueous phase amounted to only 3% to 10% of the total initial solid Fe concentration, whilst the total aqueous As remained almost constant after an initial exchange with phosphate ions. During the second month, the aqueous Fe(II) concentration remained constant, or even decreased, whereas the total quantity of As released to the solution accounted for 14% to 45% of the total initial solid As concentration. At the end of the incubation, the aqueous-phase arsenic was present predominately as As(III) whilst X-ray absorption spectroscopy indicated that more than 70% of the solid-phase arsenic was present as As(V). X-ray diffraction revealed vivianite Fe(II)3(PO4)2.8H2O in some of the experiments. A biogeochemical model was then developed to simulate these aqueous- and solid-phase results. The two main conclusions drawn from the model are that (1) As(V) is not reduced during the first incubation month with high Eh values, but rather re-adsorbed onto the ferrihydrite surface, and this state remains until arsenic reduction is energetically more favorable than iron reduction, and (2) the release of As

  2. Decoupling of arsenic and iron release from ferrihydrite suspension under reducing conditions: a biogeochemical model.

    PubMed

    Burnol, André; Garrido, Francis; Baranger, Philippe; Joulian, Catherine; Dictor, Marie-Christine; Bodénan, Françoise; Morin, Guillaume; Charlet, Laurent

    2007-11-29

    High levels of arsenic in groundwater and drinking water are a major health problem. Although the processes controlling the release of As are still not well known, the reductive dissolution of As-rich Fe oxyhydroxides has so far been a favorite hypothesis. Decoupling between arsenic and iron redox transformations has been experimentally demonstrated, but not quantitatively interpreted. Here, we report on incubation batch experiments run with As(V) sorbed on, or co-precipitated with, 2-line ferrihydrite. The biotic and abiotic processes of As release were investigated by using wet chemistry, X-ray diffraction, X-ray absorption and genomic techniques. The incubation experiments were carried out with a phosphate-rich growth medium and a community of Fe(III)-reducing bacteria under strict anoxic conditions for two months. During the first month, the release of Fe(II) in the aqueous phase amounted to only 3% to 10% of the total initial solid Fe concentration, whilst the total aqueous As remained almost constant after an initial exchange with phosphate ions. During the second month, the aqueous Fe(II) concentration remained constant, or even decreased, whereas the total quantity of As released to the solution accounted for 14% to 45% of the total initial solid As concentration. At the end of the incubation, the aqueous-phase arsenic was present predominately as As(III) whilst X-ray absorption spectroscopy indicated that more than 70% of the solid-phase arsenic was present as As(V). X-ray diffraction revealed vivianite Fe(II)3(PO4)2.8H2O in some of the experiments. A biogeochemical model was then developed to simulate these aqueous- and solid-phase results. The two main conclusions drawn from the model are that (1) As(V) is not reduced during the first incubation month with high Eh values, but rather re-adsorbed onto the ferrihydrite surface, and this state remains until arsenic reduction is energetically more favorable than iron reduction, and (2) the release of As

  3. Reduced isotope fractionation by denitrification under conditions relevant to the ocean

    NASA Astrophysics Data System (ADS)

    Kritee, K.; Sigman, Daniel M.; Granger, Julie; Ward, Bess B.; Jayakumar, Amal; Deutsch, Curtis

    2012-09-01

    Experiments with two well-studied denitrifiers and one recently isolated marine suboxic zone denitrifier show that the cellular-level denitrification N isotope effect (15ɛ) is typically lower than the canonical value of ˜25‰ under many conditions prevalent in the ocean. Across all three strains, 15ɛ is 10-15‰ at cellular nitrate reduction rates that are more representative of the environment than the very high rates under which we and previous investigators measure 15ɛ to be 20-30‰. A sharp decrease in 15ɛ is also observed in individual nitrate drawdown assays as the extracellular nitrate concentrations approach 2-35 μM and nitrate uptake becomes the rate-limiting step. On an apparently strain-specific basis, lower values of 15ɛ are observed under diverse conditions common in the natural environment: less reduced carbon sources, small inputs of oxygen, nutrient availability, agitation, and age of starter culture (i.e., initiation of assays with cells that had recently depleted a large previous nitrate amendment or were more recently in the exponential growth ("bloom") phase). A conserved oxygen-to-nitrogen isotope relationship across the experiments for all three denitrifiers (18ɛ/15ɛ = 0.93 ± 0.06 (1SD)) supports the interpretation that fractionation is imparted solely by the internal respiratory nitrate reductase, with the amplitude of 15ɛ varying with the proportional importance of cellular nitrate efflux relative to uptake. Aspects of the 15ɛ variation are unexpected; nevertheless, the occurrence of lower 15ɛ is robust. It is uncertain if our lower 15ɛ estimates apply to oceanic water column denitrification because field studies have generally yielded 15ɛwc between 20-30‰, more similar to previous culture estimates and our estimates at high cell specific nitrate reduction rates. If denitrification in the ocean's major suboxic zones does have an 15ɛ of ˜10-15‰, it would remove an apparent imbalance between global ocean N inputs and

  4. Aeroacoustic effects of reduced aft tip speed at constant thrust for a model counterrotation turboprop at takeoff conditions

    NASA Technical Reports Server (NTRS)

    Woodward, Richard P.; Hughes, Christopher E.

    1990-01-01

    A model high-speed, advanced counterrotation propeller, F7/A7, was tested in the anechoic wind tunnel at simulated takeoff and approach conditions of Mach 0.2. The propeller was operated in a baseline configuration with the forward and aft rotor blade setting angles and forward and aft rotational speeds essentially equal. Two additional configurations were tested with the aft rotor at increased blade setting angles and the rotational speed reduced to achieve overall performance similar to that of the baseline configuration. Acoustic data were taken with an axially translating microphone probe that was attached to the tunnel floor. Concurrent aerodynamic data were taken to define propeller operating conditions.

  5. Metacognition of agency is reduced in high hypnotic suggestibility.

    PubMed

    Terhune, Devin B; Hedman, Love R A

    2017-11-01

    A disruption in the sense of agency is the primary phenomenological feature of response to hypnotic suggestions but its cognitive basis remains elusive. Here we tested the proposal that distorted volition during response to suggestions arises from poor metacognition pertaining to the sources of one's control. Highly suggestible and control participants completed a motor task in which performance was reduced through surreptitious manipulations of cursor lag and stimuli speed. Highly suggestible participants did not differ from controls in performance or metacognition of performance, but their sense of agency was less sensitive to cursor lag manipulations, suggesting reduced awareness that their control was being manipulated. These results indicate that highly suggestible individuals have aberrant metacognition of agency and may be a valuable population for studying distortions in the sense of agency. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. High-pressure saline washing of allografts reduces bacterial contamination.

    PubMed

    Hirn, M Y; Salmela, P M; Vuento, R E

    2001-02-01

    60 fresh-frozen bone allografts were contaminated on the operating room floor. No bacterial growth was detected in 5 of them after contamination. The remaining 55 grafts had positive bacterial cultures and were processed with three methods: soaking in saline, soaking in antibiotic solution or washing by high-pressure saline. After high-pressure lavage, the cultures were negative in three fourths of the contaminated allografts. The corresponding figures after soaking grafts in saline and antibiotic solution were one tenth and two tenths, respectively. High-pressure saline cleansing of allografts can be recommended because it improves safety by reducing the superficial bacterial bioburden.

  7. Early age thermal conditioning immediately reduces body temperature of broiler chicks in a tropical environment.

    PubMed

    De Basilio, V; Requena, F; León, A; Vilariño, M; Picard, M

    2003-08-01

    Early age thermal conditioning (TC) durably improves resistance of broilers to heat stress and reduces body temperature (Tb). Three experiments on broiler chicks were conducted to evaluate the effects of TC at 5 d of age on Tb variation measured by thermometer between 4 and 7 d of age, under a tropical environment. Because manipulation of chickens to measure Tb with a thermometer may increase Tb, a preliminary experiment on 13 3-to-4-wk-old male broilers compared Tb measured by telemetry to Tb measured in the terminal colon during three successive periods at 22, 33, and 22 degrees C. During heat exposure, Tb rapidly increased by 0.9 degrees C and plateaued over 24 h. During the last period, seven of the broilers rapidly reduced Tb to a plateau lower than the initial Tb, although six broilers exhibited more variable Tb. Measurement by thermometer underestimated on average core Tb by 0.28 degrees C at 22 degrees C and by 0.57 degrees C at 33 degrees C, whereas Tb recorded by telemetry was not affected by manipulation of the chickens. TC reduced Tb 24 h later in the three experiments. Compared to unexposed control chicks (N), 12 h of TC at 40 degrees C did not significantly reduce Tb at 7 d of age, although 24 h did. TC at 38 and 40 degrees C over 24 h significantly reduced Tb variation from 4 to 7 d of age compared to N chicks, whereas 36 degrees C did not. Withdrawing feed from the chicks for 2 h prior to measurement did not significantly reduce Tb at 4 and 7 d of age, but Tb reduction due to TC was greater in fed chicks (0.28 degrees C) than in chicks without feed (0.05 degrees C). Early age thermal conditioning at 38 to 40 degrees C at 5 d of age for 24 h reduced body temperature of 7-d-old male broilers.

  8. Anaerobic biodegradation of soybean biodiesel and diesel blends under sulfate-reducing conditions.

    PubMed

    Wu, Shuyun; Yassine, Mohamad H; Suidan, Makram T; Venosa, Albert D

    2016-10-01

    Biotransformation of soybean biodiesel and its biodiesel/petrodiesel blends were investigated under sulfate-reducing conditions. Three blends of biodiesel, B100, B50, and B0, were treated using microbial cultures pre-acclimated to B100 (biodiesel only) and B80 (80% biodiesel and 20% petrodiesel). Results indicate that the biodiesel could be effectively biodegraded in the presence or absence of petrodiesel, whereas petrodiesel could not be biodegraded at all under sulfate-reducing conditions. The kinetics of biodegradation of individual Fatty Acid Methyl Ester (FAME) compounds and their accompanying sulfate-reduction rates were studied using a serum bottle test. As for the biodegradation of individual FAME compounds, the biodegradation rates for the saturated FAMEs decreased with increasing carbon chain length. For unsaturated FAMEs, biodegradation rates increased with increasing number of double bonds. The presence of petrodiesel had a greater effect on the rate of biodegradation of biodiesel than on the extent of removal.

  9. Anaerobic degradation and dehalogenation of chlorosalicylates and salicylate under four reducing conditions.

    PubMed

    Milligan, P W; Häggblom, M M

    2001-01-01

    The anaerobic biodegradability and transformation of the mono-and dichlorinated salicylates (2-hydroxybenzoates) was examined under denitrifying, Fe (III) reducing, sulfate reducing and methanogenic conditions. 3,6-Dichlorosalicylate and 6-chlorosalicylate are anaerobic microbial metabolites of dicamba, a widely used herbicide. Anaerobic microcosms were established with dicamba treated soil from Wyoming, and golf course drainage stream sediments from New Jersey, which were each spiked with salicylate, 3,6-dichlorosalicylate or one of the four monochlorosalicylate isomers. Salicylate was degraded under denitrifying, sulfidogenic and methanogenic conditions. In methanogenic enrichments 5-chlorosalicylate and 3-chlorosalicylate were reductively dehalogenated to salicylate which was then utilized. Dehalogenation of monochlorinated salicylates to salicylate was also observed in denitrifying chlorosalicylate degrading cultures. The study revealed that the position of the chlorine substituent as well as the predominant electron accepting process affect the rate and extent of chlorosalicylate degradation in anoxic environments.

  10. Soot formation and radiation in turbulent jet diffusion flames under normal and reduced gravity conditions

    NASA Technical Reports Server (NTRS)

    Ku, Jerry C.; Tong, LI; Sun, Jun; Greenberg, Paul S.; Griffin, Devon W.

    1993-01-01

    Most practical combustion processes, as well as fires and explosions, exhibit some characteristics of turbulent diffusion flames. For hydrocarbon fuels, the presence of soot particles significantly increases the level of radiative heat transfer from flames. In some cases, flame radiation can reach up to 75 percent of the heat release by combustion. Laminar diffusion flame results show that radiation becomes stronger under reduced gravity conditions. Therefore, detailed soot formation and radiation must be included in the flame structure analysis. A study of sooting turbulent diffusion flames under reduced-gravity conditions will not only provide necessary information for such practical issues as spacecraft fire safety, but also develop better understanding of fundamentals for diffusion combustion. In this paper, a summary of the work to date and of future plans is reported.

  11. Reduced Toxicity Conditioning and Allogeneic Hematopoietic Progenitor Cell Transplantation for Recessive Dystrophic Epidermolysis Bullosa.

    PubMed

    Geyer, Mark B; Radhakrishnan, Kavita; Giller, Roger; Umegaki, Noriko; Harel, Sivan; Kiuru, Maija; Morel, Kimberly D; LeBoeuf, Nicole; Kandel, Jessica; Bruckner, Anna; Fabricatore, Sandra; Chen, Mei; Woodley, David; McGrath, John; Baxter-Lowe, LeeAnn; Uitto, Jouni; Christiano, Angela M; Cairo, Mitchell S

    2015-09-01

    Recessive dystrophic epidermolysis bullosa is a severe, incurable, inherited blistering disease caused by COL7A1 mutations. Emerging evidence suggests hematopoietic progenitor cells (HPCs) can be reprogrammed into skin; HPC-derived cells can restore COL7 expression in COL7-deficient mice. We report two children with recessive dystrophic epidermolysis bullosa treated with reduced-toxicity conditioning and HLA-matched HPC transplantation.

  12. Retrofitting Inefficient Rooftop Air-Conditioning Units Reduces U.S. Navy Energy Use (Fact Sheet)

    SciTech Connect

    Not Available

    2014-04-01

    As part of the U.S. Navy's overall energy strategy, the National Renewable Energy Laboratory (NREL) partnered with the Naval Facilities Engineering Command (NAVFAC) to demonstrate market-ready energy efficiency measures, renewable energy generation, and energy systems integration. One such technology - retrofitting rooftop air-conditioning units with an advanced rooftop control system - was identified as a promising source for reducing energy use and costs, and can contribute to increasing energy security.

  13. Ovarian Function after Hematopoietic Cell Transplantation: A Descriptive Study Following the Use of GnRH Agonists for Myeloablative Conditioning and Observation Only for Reduced-Intensity Conditioning

    PubMed Central

    Phelan, Rachel; Mann, Elizabeth; Napurski, Char; DeFor, Todd E; Petryk, Anna; Miller, Weston P; Wagner, John E; Verneris, Michael R; Smith, Angela R

    2017-01-01

    Gonadal failure is a health and quality of life concern in hematopoietic cell transplant (HCT) survivors. While ovarian dysfunction is nearly universal following myeloablative (MA) conditioning, risk is unclear after reduced-intensity conditioning (RIC). Gonadotropin-releasing hormone agonists decrease ovarian failure rates following conventional chemotherapy but little is known about its effectiveness with HCT. We investigated the impact of leuprolide on ovarian function after MA conditioning and monitored ovarian function after RIC in this descriptive pilot study. Post-menarchal females <50 years undergoing HCT with adequate baseline ovarian function (FSH level <40 mIU/mL and normal menstruation) were eligible. Prior to MA conditioning, leuprolide was administered. Those undergoing RIC were observed. FSH was measured at various time points. Seventeen women aged 12–45 years were evaluated (7 in the intervention group and 10 observation group). Compared to the historical high rate of ovarian failure after MA conditioning, 3 of 7 evaluable Lupron recipients had ovarian failure at a median of 703 days post-transplant. Ovarian failure occurred in 1 of 10 recipients of RIC at median follow-up of 901 days. In conclusion, leuprolide may protect ovarian function after MA conditioning. Additionally, RIC with cyclophosphamide, fludarabine and low-dose TBI has a low risk of ovarian failure. PMID:27272448

  14. IMPACTS OF REDUCING CONDITIONS IN THE SATURATED ZONE AT YUCCA MOUNTAIN

    SciTech Connect

    B.W. Arnold; A. Meijer; E. Kalinina; B. Robinson; S. Kelkar; C. Jove-Colon; S. Kuzio; S. James; M. Zhu

    2006-02-28

    Variations in groundwater redox chemistry in the saturated zone near Yucca Mountain could have significant repository to the accessible environment. This study examines geochemical data relevant to the distribution of redox impacts on processes associated with the potential transport of redox-sensitive radionuclides from the proposed conditions in the saturated zone, the relationships between redox state and solubility and sorption coefficients for technetium and neptunium, and sensitivity in transport model simulations. Results indicate evidence for a zone of reducing conditions in the volcanic rocks of the saturated zone located to the east and south of the repository and along the inferred flow paths from the repository. A working hypothesis is that these reducing conditions are related to the presence of minor pyrite in the matrix of some volcanic units. Chemical equilibrium modeling of technetium solubility using EQ3/6 software codes is used to estimate the value of solubility limits as a function of Eh. Surface complexation modeling with the EQ3 code is used to estimate neptunium sorption coefficient values as a function of Eh. A general analytical approach, one-dimensional reactive transport modeling, and the three-dimensional saturated zone site-scale transport model using the FEHM software code are used to evaluate the impacts of solubility limits and enhanced sorption in reducing zones on the simulated transport of technetium and neptunium in the saturated zone. Results show that if precipitation occurs in response to flow through a reducing zone, then the peak concentration released to the accessible environment will be restricted to the solubility limit. Simulations also show that enhanced sorption within a reducing zone of modest width leads to significantly greater retardation of radionuclides in the saturated zone.

  15. Ghrelin knockout mice show decreased voluntary alcohol consumption and reduced ethanol-induced conditioned place preference.

    PubMed

    Bahi, Amine; Tolle, Virginie; Fehrentz, Jean-Alain; Brunel, Luc; Martinez, Jean; Tomasetto, Catherine-Laure; Karam, Sherif M

    2013-05-01

    Recent work suggests that stomach-derived hormone ghrelin receptor (GHS-R1A) antagonism may reduce motivational aspects of ethanol intake. In the current study we hypothesized that the endogenous GHS-R1A agonist ghrelin modulates alcohol reward mechanisms. For this purpose ethanol-induced conditioned place preference (CPP), ethanol-induced locomotor stimulation and voluntary ethanol consumption in a two-bottle choice drinking paradigm were examined under conditions where ghrelin and its receptor were blocked, either using ghrelin knockout (KO) mice or the specific ghrelin receptor (GHS-R1A) antagonist "JMV2959". We showed that ghrelin KO mice displayed lower ethanol-induced CPP than their wild-type (WT) littermates. Consistently, when injected during CPP-acquisition, JMV2959 reduced CPP-expression in C57BL/6 mice. In addition, ethanol-induced locomotor stimulation was lower in ghrelin KO mice. Moreover, GHS-R1A blockade, using JMV2959, reduced alcohol-stimulated locomotion only in WT but not in ghrelin KO mice. When alcohol consumption and preference were assessed using the two-bottle choice test, both genetic deletion of ghrelin and pharmacological antagonism of the GHS-R1A (JMV2959) reduced voluntary alcohol consumption and preference. Finally, JMV2959-induced reduction of alcohol intake was only observed in WT but not in ghrelin KO mice. Taken together, these results suggest that ghrelin neurotransmission is necessary for the stimulatory effect of ethanol to occur, whereas lack of ghrelin leads to changes that reduce the voluntary intake as well as conditioned reward by ethanol. Our findings reveal a major, novel role for ghrelin in mediating ethanol behavior, and add to growing evidence that ghrelin is a key mediator of the effects of multiple abused drugs.

  16. Conditioning of the abdominal cavity reduces tumor implantation in a laparoscopic mouse model.

    PubMed

    Binda, Maria Mercedes; Corona, Roberta; Amant, Frederic; Koninckx, Philippe Robert

    2014-07-01

    The addition of 4 % O2 and 10 % N2O to the CO2 pneumoperitoneum (PP), together with slight cooling and humidification (conditioning), contributes to reducing adhesions by preventing mesothelial damage. We investigated the effect of peritoneal damage during laparoscopy on tumor implantation. In Experiment 1, different tumor cell concentrations were injected into control mice without PP and into mice with 60-min dry CO2PP (mesothelial damage). In Experiment 2, tumor cells were injected into control mice (group I) and in mice with mesothelial damage (group II). In groups III to VI, mesothelial damage was decreased by adding humidification, humidification + 10 % N2O, humidification + 10 % N2O + 4 % O2, and conditioning, respectively. In Experiment 1, the tumors increased with the number of cells injected and with mesothelial damage in the abdominal cavity (p = 0.018) and abdominal wall (p < 0.0001). Experiment 2 confirmed that 60 min of dry CO2PP increased the number of tumors in the abdominal cavity and wall (p = 0.026 and p = 0.003, respectively). The number of tumors was decreased in the abdominal cavity by conditioning (p = 0.030) and in the abdominal wall using humidified CO2 (p = 0.032) or conditioning (p = 0.026). Tumor implantation was enhanced by peritoneal damage (60 min of dry CO2PP and desiccation), but this was prevented by conditioning. If confirmed in humans, conditioning would become important for oncologic surgery.

  17. Donor Chimerism Early after Reduced-intensity Conditioning Hematopoietic Stem Cell Transplantation Predicts Relapse and Survival

    PubMed Central

    Koreth, John; Kim, Haesook T.; Nikiforow, Sarah; Milford, Edgar L.; Armand, Philippe; Cutler, Corey; Glotzbecker, Brett; Ho, Vincent T.; Antin, Joseph H.; Soiffer, Robert J.; Ritz, Jerome; Alyea, Edwin P.

    2015-01-01

    The impact of early donor cell chimerism on outcomes of T-replete reduced-intensity conditioning (RIC) hematopoietic stem cell transplantation (HSCT) is ill-defined. We evaluated day 30 (D30) and 100 (D100) total donor cell chimerism after RIC HSCT undertaken between 2002 and 2010 at our institution, excluding patients who died or relapsed before D30. When available, donor T-cell chimerism was also assessed. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), relapse and non-relapse mortality (NRM). 688 patients with hematologic malignancies (48% myeloid; 52% lymphoid) and a median age of 57 years (range, 18-74) undergoing RIC HSCT with T-replete donor grafts (97% peripheral blood; 92% HLA-matched) and median follow-up of 58.2 months (range, 12.6-120.7) were evaluated. In multivariable analysis total donor cell and T-cell chimerism at D30 and D100 each predicted RIC HSCT outcomes, with D100 total donor cell chimerism most predictive. D100 total donor cell chimerism <90% was associated with increased relapse (HR 2.54, 95% CI 1.83-3.51, p<0.0001), impaired PFS (HR 2.01, 95% CI 1.53-2.65, p<0.0001) and worse OS (1.50, 95% CI 1.11-2.04, p=0.009), but not NRM (HR 0.76; 95% CI 0.44-2.27, p=0.33). There was no additional utility of incorporating sustained D30-D100 total donor cell chimerism, or T-cell chimerism. Low donor chimerism early after RIC HSCT is an independent risk factor for relapse and impaired survival. Donor chimerism assessment early after RIC HSCT can prognosticate for long-term outcomes and help identify high-risk patient cohorts that may benefit from additional therapeutic interventions. PMID:24907627

  18. Effect of modeled reduced gravity conditions on bacterial morphology and physiology

    PubMed Central

    2012-01-01

    Background Bacterial phenotypes result from responses to environmental conditions under which these organisms grow; reduced gravity has been demonstrated in many studies as an environmental condition that profoundly influences microorganisms. In this study, we focused on low-shear stress, modeled reduced gravity (MRG) conditions and examined, for Escherichia coli and Staphlyococcus aureus, a suite of bacterial responses (including total protein concentrations, biovolume, membrane potential and membrane integrity) in rich and dilute media and at exponential and stationary phases for growth. The parameters selected have not been studied in E. coli and S. aureus under MRG conditions and provide critical information about bacterial viability and potential for population growth. Results With the exception of S. aureus in dilute Luria Bertani (LB) broth, specific growth rates (based on optical density) of the bacteria were not significantly different between normal gravity (NG) and MRG conditions. However, significantly higher bacterial yields were observed for both bacteria under MRG than NG, irrespective of the medium with the exception of E. coli grown in LB. Also, enumeration of cells after staining with 4',6-diamidino-2-phenylindole showed that significantly higher numbers were achieved under MRG conditions during stationary phase for E. coli and S. aureus grown in M9 and dilute LB, respectively. In addition, with the exception of smaller S. aureus volume under MRG conditions at exponential phase in dilute LB, biovolume and protein concentrations per cell did not significantly differ between MRG and NG treatments. Both E. coli and S. aureus had higher average membrane potential and integrity under MRG than NG conditions; however, these responses varied with growth medium and growth phase. Conclusions Overall, our data provides novel information about E. coli and S. aureus membrane potential and integrity and suggest that bacteria are physiologically more active and

  19. Effect of modeled reduced gravity conditions on bacterial morphology and physiology.

    PubMed

    Vukanti, Raja; Model, Michael A; Leff, Laura G

    2012-01-12

    Bacterial phenotypes result from responses to environmental conditions under which these organisms grow; reduced gravity has been demonstrated in many studies as an environmental condition that profoundly influences microorganisms. In this study, we focused on low-shear stress, modeled reduced gravity (MRG) conditions and examined, for Escherichia coli and Staphlyococcus aureus, a suite of bacterial responses (including total protein concentrations, biovolume, membrane potential and membrane integrity) in rich and dilute media and at exponential and stationary phases for growth. The parameters selected have not been studied in E. coli and S. aureus under MRG conditions and provide critical information about bacterial viability and potential for population growth. With the exception of S. aureus in dilute Luria Bertani (LB) broth, specific growth rates (based on optical density) of the bacteria were not significantly different between normal gravity (NG) and MRG conditions. However, significantly higher bacterial yields were observed for both bacteria under MRG than NG, irrespective of the medium with the exception of E. coli grown in LB. Also, enumeration of cells after staining with 4',6-diamidino-2-phenylindole showed that significantly higher numbers were achieved under MRG conditions during stationary phase for E. coli and S. aureus grown in M9 and dilute LB, respectively. In addition, with the exception of smaller S. aureus volume under MRG conditions at exponential phase in dilute LB, biovolume and protein concentrations per cell did not significantly differ between MRG and NG treatments. Both E. coli and S. aureus had higher average membrane potential and integrity under MRG than NG conditions; however, these responses varied with growth medium and growth phase. Overall, our data provides novel information about E. coli and S. aureus membrane potential and integrity and suggest that bacteria are physiologically more active and a larger percentage are viable

  20. Migration Behavior of Plutonium in Compacted Bentonite Under Reducing Condition Using Electromigration

    SciTech Connect

    Kazuya Idemitsu; Yosuke Yamasaki; Syeda Afsarun Nessa; Yaohiro Inagaki; Tatsumi Arima; Toshiaki Mitsugashira; Mitsuo Hara; Yoshimitsu Suzuki

    2007-07-01

    Carbon steel is one of the candidate overpack materials for high-level waste disposal and is expected to assure complete containment of vitrified waste glass during an initial period of 1000 years in Japan. Carbon steel overpack will be corroded by consuming oxygen introduced by repository construction after closure of repository and then will keep the reducing environment in the vicinity of repository. The migration of iron corrosion products through the buffer material will affect migration of redox-sensitive radionuclides. Therefore the authors have carried out electromigration experiments with source of iron ions supplied by anode corrosion of iron coupons attached to compacted bentonite. Authors tried to use plutonium in this experimental configuration to obtain the knowledge of migration behavior of actinides. Authors also used cesium as reference. The concentrations of iron and sodium showed nearly complementary distributions. It is expected that iron ion could migrate as ferrous ion through the interlayer of montmorillonite replacing exchangeable sodium ions in the interlayer. Concentration profiles of plutonium in bentonite grew as time supplying electric potential as long as 168 h. Plutonium migrated from the iron anode toward cathode as deeper than 1 mm of the interior of bentonite even in 48 h, though plutonium could not diffuse 1 mm for 2 years. On the other hand, profiles of cesium were reported to be controlled by ordinary diffusion because of large diffusion coefficient of cesium in bentonite as large as 10{sup -12} m{sup 2}/s. Drift of the cesium profile by electric potential gradient could be observed clearly after 240 h at individual experiment for cesium. Apparent dispersion coefficients of plutonium were calculated from the profiles and were as large as 10{sup -13} m{sup 2}/s. Since plutonium migration was accelerated by electric potential, plutonium chemical species would have positive charge and were estimated as PuOH{sup 2+} or PuCl{sup 2

  1. High Performance Parallel Algorithms for Improved Reduced-Order Modeling

    DTIC Science & Technology

    2008-05-04

    HIGH PERFORMANCE PARALLEL ALGORITHMS FOR IMPROVED REDUCED-ORDER MODELING AFOSR FA9550-05-1-0449 FINAL REPORT Chris Beattie, Jeff Borggaard, Serkan ... Serkan Gugercin and Traian Iliescu (co-PIs) Post-Docs Andrew Duggelby, Alexander Hay and Sonja Schlaugh Students Weston Hunter, Denis Kovacs, Miroslav...internship to discuss his research. [Contacts: Chris Camphouse (937) 255-6326, James Myatt (937) 255-8498] Synergistic Activities 1. Serkan Gugerin, with

  2. High average power solid state laser power conditioning system

    SciTech Connect

    Steinkraus, R.F.

    1987-03-03

    The power conditioning system for the High Average Power Laser program at Lawrence Livermore National Laboratory (LLNL) is described. The system has been operational for two years. It is high voltage, high power, fault protected, and solid state. The power conditioning system drives flashlamps that pump solid state lasers. Flashlamps are driven by silicon control rectifier (SCR) switched, resonant charged, (LC) discharge pulse forming networks (PFNs). The system uses fiber optics for control and diagnostics. Energy and thermal diagnostics are monitored by computers.

  3. Root surface conditioning with nicotine or cotinine reduces viability and density of fibroblasts in vitro.

    PubMed

    Martinez, Aurora Esmeralda Traverso; Silverio, Karina Gonzales; Fogo, Jose Carlos; Kirkwood, Keith Lough; Rossa, Carlos

    2005-09-01

    The purpose of study was to evaluate fibroblast attachment and cellular morphology on root surfaces chemically conditioned with nicotine or cotinine. A secondary objective was to determine if mechanical scaling and root planning of these chemically conditioned surfaces would alter cellular attachment. Root surface dentin specimens were prepared from uniradicular teeth of non-smoking patients. Specimens were randomly assigned to two experimental groups: no treatment (chemical conditioning only) and scaling and root planning after conditioning (SRPC). The concentrations of the tested substances were in the range of 0-1 mg/mL (nicotine) and 0-1 g/mL (cotinine). After a 24-h conditioning period, dentin slices were incubated with continuous lineage of fibroblastic cells from rat (McCoy cells) for another 24 h. Specimens were prepared for SEM analysis and microphotographs. The statistical analysis of the data indicated significant alteration of cellular morphology on fibroblasts that were grown on root surface exposed to nicotine concentrations greater than 1 ?g/mL. This effect of nicotine was not reduced by SRPC. On the other hand, in the SRPC group cellular density was greater. For cotinine-conditioned specimens, the greater concentrations also led to alteration on morphology, and these alterations were observed in the SRPC group as well. Cotinine did not induce significant changes on cellular density. The results indicated that fibroblasts are negatively influenced by nicotine present on the dentin substrate and also that scaling may reduce these effects. Cotinine treatment on root surfaces may alter cell morphology and density but these effects were less severe than that promoted by nicotine, and were not affected by scaling.

  4. Personalized Fludarabine Dosing To Reduce Non-Relapse Mortality In Hematopoietic Stem Cell Transplant Recipients Receiving Reduced Intensity Conditioning

    PubMed Central

    Sanghavi, Kinjal; Wiseman, Anthony; Kirstein, Mark N.; Cao, Qing; Brundage, Richard; Jensen, Kyle; Rogosheske, John; Kurtzweil, Andy; Long-Boyle, Janel; Wagner, John; Warlick, Erica D.; Brunstein, Claudio G; Weisdorf, Daniel J.; Jacobson, Pamala A.

    2016-01-01

    Patients undergoing hematopoietic cell transplantation (HCT) with reduced intensity conditioning (RIC) commonly receive fludarabine. Higher exposure of F-ara-A, the active component of fludarabine, has been associated with a greater risk of non-relapse mortality (NRM). We sought to develop a model for fludarabine dosing in adult HCT recipients that would allow for precise dose targeting and predict adverse clinical outcomes. We developed a pharmacokinetic model from 87 adults undergoing allogeneic RIC HCT that predicts F-ara-A population clearance (Clpop) accounting for ideal body weight and renal function. We then applied the developed model to an independent cohort of 240 patients to identify whether model predictions were associated with NRM and acute graft vs host disease (GVHD). Renal mechanisms accounted for 35.6% of total F-ara-A Clpop. In the independent cohort the hazard ratio of NRM at day 100 was significantly higher in patients with predicted F-ara-A clearance (Clpred) <8.50 L/hr (p<0.01) and area under the curve (AUCpred)>6.00 μg*hr/mL (p=0.01). A lower Clpred was also associated with more NRM at month 6 (p=0.01) and trended towards significance at 12 months (p=0.05). In multivariate analysis, low fludarabine clearance trended towards higher risk of acute GVHD (p=0.05). We developed a model that predicts an individual's systemic F-ara-A exposure accounting for kidney function and weight. This model may provide guidance in dosing in overweight individuals and those with altered kidney function. PMID:27094990

  5. Tetrahydrocannabinolic acid reduces nausea-induced conditioned gaping in rats and vomiting in Suncus murinus

    PubMed Central

    Rock, E M; Kopstick, R L; Limebeer, C L; Parker, L A

    2013-01-01

    BACKGROUND AND PURPOSE We evaluated the anti-emetic and anti-nausea properties of the acid precursor of Δ9-tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), and determined its mechanism of action in these animal models. EXPERIMENTAL APPROACH We investigated the effect of THCA on lithium chloride- (LiCl) induced conditioned gaping (nausea-induced behaviour) to a flavour, and context (a model of anticipatory nausea) in rats, and on LiCl-induced vomiting in Suncus murinus. Furthermore, we investigated THCA's ability to induce hypothermia and suppress locomotion [rodent tasks to assess cannabinoid1 (CB1) receptor agonist-like activity], and measured plasma and brain THCA and THC levels. We also determined whether THCA's effect could be blocked by pretreatment with SR141716 (SR, a CB1 receptor antagonist). KEY RESULTS In rats, THCA (0.05 and/or 0.5 mg·kg−1) suppressed LiCl-induced conditioned gaping to a flavour and context; the latter effect blocked by the CB1 receptor antagonist, SR, but not by the 5-hydroxytryptamine-1A receptor antagonist, WAY100635. In S. murinus, THCA (0.05 and 0.5 mg·kg−1) reduced LiCl-induced vomiting, an effect that was reversed with SR. A comparatively low dose of THC (0.05 mg·kg−1) did not suppress conditioned gaping to a LiCl-paired flavour or context. THCA did not induce hypothermia or reduce locomotion, indicating non-CB1 agonist-like effects. THCA, but not THC was detected in plasma samples. CONCLUSIONS AND IMPLICATIONS THCA potently reduced conditioned gaping in rats and vomiting in S. murinus, effects that were blocked by SR. These data suggest that THCA may be a more potent alternative to THC in the treatment of nausea and vomiting. PMID:23889598

  6. Naphthalene and benzene degradation under Fe(III)-reducing conditions in petroleum-contaminated aquifers

    USGS Publications Warehouse

    Anderson, Robert T.; Lovely, Derek R.

    1999-01-01

    Naphthalene was oxidized anaerobically to CO2 in sediments collected from a petroleum-contaminated aquifer in Bemidji, Minnesota in which Fe(III) reduction was the terminal electron-accepting process. Naphthalene was not oxidized in sediments from the methanogenic zone at Bemidji or in sediments from the Fe(III)-reducing zone of other petroleum-contaminated aquifers studied. In a profile across the Fe(III)-reducing zone of the Bemidji aquifer, rates of naphthalene oxidation were fastest in sediments with the highest proportion of Fe(III), which was also the zone of the most rapid degradation of benzene, toluene, and acetate. The comparative studies attempted to elucidate factors that might account for the fact that unsubstituted aromatic hydrocarbons such as benzene and naphthalene were degraded under Fe(III)-reducing conditions at Bemidji, but not at the other aquifers examined. These studies indicated that the ability of Fe(III)-reducing microorganisms to degrade benzene and naphthalene at the Bemidji site cannot be attributed to groundwater components that make Fe(III) more available for reduction or other potential factors that were evaluated. However, unlike the other aquifers evaluated, uncontaminated sediments at the Bemidji site could be adapted for anaerobic benzene degradation merely with the addition of benzene. These findings indicate that Bemidji sediments naturally contain Fe(III) reducers capable of degradation of unsubstituted aromatic hydrocarbons.

  7. Sulfate-reducing bacteria lower sulfur-mediated pitting corrosion under conditions of oxygen ingress.

    PubMed

    Johnston, Shawna L; Voordouw, Gerrit

    2012-08-21

    The effect of oxygen ingress into sour water containing dissolved sulfide on the production of sulfur and polysulfide (S-PS) and associated iron corrosion was investigated. Biotic (active SRB present), abiotic (autoclaved SRB present), and chemical (no bacteria present) conditions were compared. Under biotic conditions formation of S-PS was only seen at a high ratio of oxygen to sulfide (R(OS)) of 1 to 2.4. General corrosion rates increased 10-fold to 0.10 mm/yr under these conditions. Under abiotic and chemical conditions S-PS formation increased over the entire range of R(OS) with general corrosion rates reaching 0.06 mm/yr. Although general corrosion rates were thus highest under biotic conditions, biotically corroded coupons showed much less pitting corrosion. Maximum pit depth increased to 40-80 μm with increasing R(OS) for coupons incubated for 1 month under abiotic or chemical conditions but not for biotically incubated coupons (10 μm). This appeared to be related to the properties and size of the sulfur formed, which was hydrophobic and in excess of 10 μm under chemical or abiotic conditions and hydrophilic and 0.5 to 1 μm under biotic conditions. Hence, perhaps contrary to expectation, SRB lowered pitting corrosion rates under conditions of oxygen ingress due to their ability to respire oxygen and produce a less aggressive form of sulfur. Microbial control, which is usually required in sour systems, may be counterproductive under these conditions.

  8. Reduced CO2 fertilization effect in temperate C3 grasslands under more extreme weather conditions

    NASA Astrophysics Data System (ADS)

    Obermeier, W. A.; Lehnert, L. W.; Kammann, C. I.; Müller, C.; Grünhage, L.; Luterbacher, J.; Erbs, M.; Moser, G.; Seibert, R.; Yuan, N.; Bendix, J.

    2017-02-01

    The increase in atmospheric greenhouse gas concentrations from anthropogenic activities is the major driver of recent global climate change. The stimulation of plant photosynthesis due to rising atmospheric carbon dioxide concentrations ([CO2]) is widely assumed to increase the net primary productivity (NPP) of C3 plants--the CO2 fertilization effect (CFE). However, the magnitude and persistence of the CFE under future climates, including more frequent weather extremes, are controversial. Here we use data from 16 years of temperate grassland grown under `free-air carbon dioxide enrichment’ conditions to show that the CFE on above-ground biomass is strongest under local average environmental conditions. The observed CFE was reduced or disappeared under wetter, drier and/or hotter conditions when the forcing variable exceeded its intermediate regime. This is in contrast to predictions of an increased CO2 fertilization effect under drier and warmer conditions. Such extreme weather conditions are projected to occur more intensely and frequently under future climate scenarios. Consequently, current biogeochemical models might overestimate the future NPP sink capacity of temperate C3 grasslands and hence underestimate future atmospheric [CO2] increase.

  9. Reduced CO2 fertilization effect in temperate C3 grasslands under more extreme weather conditions

    NASA Astrophysics Data System (ADS)

    Obermeier, W. A.; Lehnert, L. W.; Kammann, C. I.; Müller, C.; Grünhage, L.; Luterbacher, J.; Erbs, M.; Moser, G.; Seibert, R.; Yuan, N.; Bendix, J.

    2016-12-01

    The increase in atmospheric greenhouse gas concentrations from anthropogenic activities is the major driver of recent global climate change. The stimulation of plant photosynthesis due to rising atmospheric carbon dioxide concentrations ([CO2]) is widely assumed to increase the net primary productivity (NPP) of C3 plants--the CO2 fertilization effect (CFE). However, the magnitude and persistence of the CFE under future climates, including more frequent weather extremes, are controversial. Here we use data from 16 years of temperate grassland grown under `free-air carbon dioxide enrichment’ conditions to show that the CFE on above-ground biomass is strongest under local average environmental conditions. The observed CFE was reduced or disappeared under wetter, drier and/or hotter conditions when the forcing variable exceeded its intermediate regime. This is in contrast to predictions of an increased CO2 fertilization effect under drier and warmer conditions. Such extreme weather conditions are projected to occur more intensely and frequently under future climate scenarios. Consequently, current biogeochemical models might overestimate the future NPP sink capacity of temperate C3 grasslands and hence underestimate future atmospheric [CO2] increase.

  10. A high energy output nanogenerator based on reduced graphene oxide

    NASA Astrophysics Data System (ADS)

    Li, Weiping; Zhang, Yupeng; Liu, Liangliang; Li, Delong; Liao, Lei; Pan, Chunxu

    2015-10-01

    In this paper, we report a novel graphene-based nanogenerator for high energy harvesting. Experimental and theoretical results revealed that the energy output mechanism is the joint action of the strain effect (band engineering) and the triboelectric effect of reduced graphene oxide. It was found that the current could be adjusted by experimental parameters, such as the electrolyte concentration and rotation rate. Furthermore, the voltage output could be amplified by series connection of the system. Compared with other nanogenerators, the present graphene-based nanogenerator provides advantages, such as simple assembly, flexibility and high structural stability. It is expected that this nanogenerator will be of potential application in active sensors and sustainable power sources.In this paper, we report a novel graphene-based nanogenerator for high energy harvesting. Experimental and theoretical results revealed that the energy output mechanism is the joint action of the strain effect (band engineering) and the triboelectric effect of reduced graphene oxide. It was found that the current could be adjusted by experimental parameters, such as the electrolyte concentration and rotation rate. Furthermore, the voltage output could be amplified by series connection of the system. Compared with other nanogenerators, the present graphene-based nanogenerator provides advantages, such as simple assembly, flexibility and high structural stability. It is expected that this nanogenerator will be of potential application in active sensors and sustainable power sources. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr04971g

  11. Mussel fishery affects diet and reduces body condition of Eiders Somateria mollissima in the Wadden Sea

    NASA Astrophysics Data System (ADS)

    Laursen, Karsten; Asferg, Karen S.; Frikke, John; Sunde, Peter

    2009-06-01

    Although the Danish Wadden Sea is of international importance for several bird species, large-scale blue mussel Mytilus edulis fishing took place from 1984-1987, ceasing thereafter due to low mussel stocks. Mussel fishing removes much of the blue mussel biomass, especially larger individuals. Hence we predict that intensive mussel fishing will affect their predators, such as the Eider Somateria mollissima, which is predominantly a blue mussel feeder by, 1) reducing the amount of blue mussels in their diet relative to alternative prey items, 2) exploitation of smaller blue mussel shell classes, 3) loss of body condition, 4) changing feeding distribution to aggregate to the remaining mussel stocks, and 5) decreasing numbers. Before winter 1986/87 blue mussel biomass was estimated at 40,600 tons, decreasing to 15,400 tons in 1987/88 due to mussel fishery. We collected Eiders in both periods to monitor their diet and body mass and used aerial surveys to determine changes in numbers and distribution. Between the two periods, blue mussels declined in the Eiders diet, numbers of Eiders with empty stomachs increased and the mean length of blue mussel taken by Eiders decreased. Eider body condition declined from 1986/87 to 1987/88, mostly the result of the reduction in numbers of individuals with blue mussel remains in their gizzards and in better body condition compared to those taking alternative food items or having empty gizzards. Eiders shifted their distribution from the southern part of the Danish Wadden Sea to the northern part, where the remaining blue mussel stocks were situated. Eider numbers were lowest in 1987/88, the year of lowest blue mussel stocks. We conclude that intensive mussel fishery affected the Eider's diet, reduced their body condition and affected distribution and abundance. The results also showed that availability of blue mussels may have a key role in building up and maintaining body condition in Eiders during winter.

  12. Dissolution and Mobilization of Uranium in a Reduced Sediment by Natural Humic Substances under Anaerobic Conditions

    SciTech Connect

    Gu, Baohua; Luo, Wensui

    2009-01-01

    Biological reduction and precipitation of uranium (U) has been proposed as a remedial option for immobilizing uranium at contaminated sites, but the long-term stability and mobility of uranium remain a concern because it is neither removed nor destroyed. In this study, the dissolution and mobilization of reduced and oxidized forms of uranium [U(IV) and U(VI)] by natural humic substances were investigated in batch and column flow systems using a bioreduced sediment containing both U(IV) and U(VI). The addition of humic substances significantly increased the dissolution of U(IV) under anaerobic conditions. Humic acid (HA) was found to be more effective than fulvic acid (FA) in dissolving U(IV) in either 1 mM KCl or KHCO3 background solution. However, more U(VI) was dissolved in 1 mM KHCO3 than in 1 mM KCl background electrolytes. The HA also was found to be more effective than FA in mobilizing uranium under reducing and column flow conditions, although an accumulative amount of eluted U(VI) and U(IV) was relatively low (<60 g) after leaching with ~97 pore volumes of the humic solution in 1 mM KHCO3. These observations suggest that natural humic substances could potentially influence the long-term stability of bioreduced U(IV) even under strong reducing environments.

  13. Evaluation of redox indicators for determining sulfate-reducing and dechlorinating conditions.

    PubMed

    Jones, Brian D; Ingle, James D

    2005-11-01

    An in situ methodology based on covalently bonded redox indicators has been developed for determining when sulfate-reducing conditions exist in environmental samples. Three immobilized redox indicators [thionine (Thi, formal potential at pH 7 (E(0')7) equals 52 mV), cresyl violet (CV, E(0')7 = -81 mV), and phenosafranine (PSaf, E(0')7 = -267 mV)] were tested for their response to sulfide in synthetic solutions and under sulfate-reducing conditions in wastewater slurries. The byproduct of the sulfate-reducing process, sulfide, was found to couple well to CV in the concentration range of 1-100 microM total sulfide ([S(-II)]) and the pH range of 6-8. Thi, the indicator with the highest formal potential, reacts rapidly with sulfide at levels well below 1 microM while PSaf, the indicator with the lowest formal potential, does not couple to sulfide at levels in excess of 100 microM [S(-II)]. The degree of reduction of the indicators (i.e., the fraction of cresyl violet oxidized) in contact with a given level of sulfide can be modeled qualitatively with an equilibrium expression for [S(-II)]-indicator based on the Nernst equation assuming that rhombic sulfur is the product of sulfide oxidation. In a groundwater sample with dechlorinating microbes, reduction of Thi and partial reduction of CV correlated with dechlorination of TCE to cis-DCE.

  14. The High School Strength and Conditioning Professional: A Job Description.

    ERIC Educational Resources Information Center

    Best, Randy

    2001-01-01

    Presents a job description for the high school strength and conditioning professional, who is in a unique position to integrate athletics and academics, highlighting: minimum qualifications; school-related benefits derived from employing a strength and conditioning professional; whom the professional reports to and works with; job…

  15. High Speed Gear Sized and Configured to Reduce Windage Loss

    NASA Technical Reports Server (NTRS)

    Kunz, Robert F. (Inventor); Medvitz, Richard B. (Inventor); Hill, Matthew John (Inventor)

    2013-01-01

    A gear and drive system utilizing the gear include teeth. Each of the teeth has a first side and a second side opposite the first side that extends from a body of the gear. For each tooth of the gear, a first extended portion is attached to the first side of the tooth to divert flow of fluid adjacent to the body of the gear to reduce windage losses that occur when the gear rotates. The gear may be utilized in drive systems that may have high rotational speeds, such as speeds where the tip velocities are greater than or equal to about 68 m/s. Some embodiments of the gear may also utilize teeth that also have second extended portions attached to the second sides of the teeth to divert flow of fluid adjacent to the body of the gear to reduce windage losses that occur when the gear rotates.

  16. Ischaemic conditioning reduces kidney injury in an experimental large-animal model of warm renal ischaemia.

    PubMed

    Hunter, J P; Hosgood, S A; Barlow, A D; Nicholson, M L

    2015-11-01

    techniques in renal transplantation have not yet established the optimal technique and timing of conditioning. In this study, a large-animal model of renal warm ischaemia was used to compare different conditioning techniques. Postconditioning applied directly to the renal artery was shown to reduce renal injury. Furthermore, new evidence is provided that shorter cycles of ischaemic postconditioning than previously described can protect against renal injury. Evidence from a large-animal model is provided for different conditioning techniques. The beneficial postconditioning technique described is straightforward to perform and provides an alternative method of conditioning following renal transplantation, with potential for application in clinical practice. © 2015 BJS Society Ltd Published by John Wiley & Sons Ltd.

  17. High perceptual load leads to both reduced gain and broader orientation tuning

    PubMed Central

    Stolte, Moritz; Bahrami, Bahador; Lavie, Nilli

    2014-01-01

    Due to its limited capacity, visual perception depends on the allocation of attention. The resultant phenomena of inattentional blindness, accompanied by reduced sensory visual cortex response to unattended stimuli in conditions of high perceptual load in the attended task, are now well established (Lavie, 2005; Lavie, 2010, for reviews). However, the underlying mechanisms for these effects remain to be elucidated. Specifically, is reduced perceptual processing under high perceptual load a result of reduced sensory signal gain, broader tuning, or both? We examined this question with psychophysical measures of orientation tuning under different levels of perceptual load in the task performed. Our results show that increased perceptual load leads to both reduced sensory signal and broadening of tuning. These results clarify the effects of attention on elementary visual perception and suggest that high perceptual load is critical for attentional effects on sensory tuning. PMID:24610952

  18. Photosynthesis, Light Use Efficiency, and Yield of Reduced-Chlorophyll Soybean Mutants in Field Conditions.

    PubMed

    Slattery, Rebecca A; VanLoocke, Andy; Bernacchi, Carl J; Zhu, Xin-Guang; Ort, Donald R

    2017-01-01

    Reducing chlorophyll (chl) content may improve the conversion efficiency of absorbed photosynthetically active radiation into biomass and therefore yield in dense monoculture crops by improving light penetration and distribution within the canopy. The effects of reduced chl on leaf and canopy photosynthesis and photosynthetic efficiency were studied in two reportedly robust reduced-chl soybean mutants, Y11y11 and y9y9, in comparison to the wild-type (WT) "Clark" cultivar. Both mutants were characterized during the 2012 growing season whereas only the Y11y11 mutant was characterized during the 2013 growing season. Chl deficiency led to greater rates of leaf-level photosynthesis per absorbed photon early in the growing season when mutant chl content was ∼35% of the WT, but there was no effect on photosynthesis later in the season when mutant leaf chl approached 50% of the WT. Transient benefits of reduced chl at the leaf level did not translate to improvements in canopy-level processes. Reduced pigmentation in these mutants was linked to lower water use efficiency, which may have dampened any photosynthetic benefits of reduced chl, especially since both growing seasons experienced significant drought conditions. These results, while not confirming our hypothesis or an earlier published study in which the Y11y11 mutant significantly outyielded the WT, do demonstrate that soybean significantly overinvests in chl. Despite a >50% chl reduction, there was little negative impact on biomass accumulation or yield, and the small negative effects present were likely due to pleiotropic effects of the mutation. This outcome points to an opportunity to reinvest nitrogen and energy resources that would otherwise be used in pigment-proteins into increasing biochemical photosynthetic capacity, thereby improving canopy photosynthesis and biomass production.

  19. Photosynthesis, Light Use Efficiency, and Yield of Reduced-Chlorophyll Soybean Mutants in Field Conditions

    PubMed Central

    Slattery, Rebecca A.; VanLoocke, Andy; Bernacchi, Carl J.; Zhu, Xin-Guang; Ort, Donald R.

    2017-01-01

    Reducing chlorophyll (chl) content may improve the conversion efficiency of absorbed photosynthetically active radiation into biomass and therefore yield in dense monoculture crops by improving light penetration and distribution within the canopy. The effects of reduced chl on leaf and canopy photosynthesis and photosynthetic efficiency were studied in two reportedly robust reduced-chl soybean mutants, Y11y11 and y9y9, in comparison to the wild-type (WT) “Clark” cultivar. Both mutants were characterized during the 2012 growing season whereas only the Y11y11 mutant was characterized during the 2013 growing season. Chl deficiency led to greater rates of leaf-level photosynthesis per absorbed photon early in the growing season when mutant chl content was ∼35% of the WT, but there was no effect on photosynthesis later in the season when mutant leaf chl approached 50% of the WT. Transient benefits of reduced chl at the leaf level did not translate to improvements in canopy-level processes. Reduced pigmentation in these mutants was linked to lower water use efficiency, which may have dampened any photosynthetic benefits of reduced chl, especially since both growing seasons experienced significant drought conditions. These results, while not confirming our hypothesis or an earlier published study in which the Y11y11 mutant significantly outyielded the WT, do demonstrate that soybean significantly overinvests in chl. Despite a >50% chl reduction, there was little negative impact on biomass accumulation or yield, and the small negative effects present were likely due to pleiotropic effects of the mutation. This outcome points to an opportunity to reinvest nitrogen and energy resources that would otherwise be used in pigment-proteins into increasing biochemical photosynthetic capacity, thereby improving canopy photosynthesis and biomass production. PMID:28458677

  20. Development of air conditioning technologies to reduce CO2 emissions in the commercial sector

    PubMed Central

    Yoshida, Yukiko

    2006-01-01

    Background Architectural methods that take into account global environmental conservation generally concentrate on mitigating the heat load of buildings. Here, we evaluate the reduction of carbon dioxide (CO2) emissions that can be achieved by improving heating, ventilating, and air conditioning (HVAC) technologies. Results The Climate Change Research Hall (CCRH) of the National Institute for Environmental Studies (NIES) is used as a case study. CCRH was built in line with the "Green Government Buildings" program of the Government Buildings Department at the Ministry of Land, Infrastructure and Transport in Japan. We have assessed the technology used in this building, and found that there is a possibility to reduce energy consumption in the HVAC system by 30%. Conclusion Saving energy reduces CO2 emissions in the commercial sector, although emission factors depend on the country or region. Consequently, energy savings potential may serve as a criterion in selecting HVAC technologies with respect to emission reduction targets. PMID:17062161

  1. Development of air conditioning technologies to reduce CO2 emissions in the commercial sector.

    PubMed

    Yoshida, Yukiko

    2006-10-25

    Architectural methods that take into account global environmental conservation generally concentrate on mitigating the heat load of buildings. Here, we evaluate the reduction of carbon dioxide (CO2) emissions that can be achieved by improving heating, ventilating, and air conditioning (HVAC) technologies. The Climate Change Research Hall (CCRH) of the National Institute for Environmental Studies (NIES) is used as a case study. CCRH was built in line with the "Green Government Buildings" program of the Government Buildings Department at the Ministry of Land, Infrastructure and Transport in Japan. We have assessed the technology used in this building, and found that there is a possibility to reduce energy consumption in the HVAC system by 30%. Saving energy reduces CO2 emissions in the commercial sector, although emission factors depend on the country or region. Consequently, energy savings potential may serve as a criterion in selecting HVAC technologies with respect to emission reduction targets.

  2. Reduced hydrogen embrittlement susceptibility in platinum implanted high strength steel

    NASA Astrophysics Data System (ADS)

    Cowie, J. G.; Lowder, L. J.; Culbertson, R. J.; Kosik, W. E.; Brown, R.

    1991-07-01

    High strength steels suffer from a high susceptibility to hydrogen embrittlement in a corrosive atmosphere, a factor which limits their usefulness. A good catalyst, such as platinum, present on the surface of the steel may lead to a low value of hydrogen overvoltage, thereby reducing the accumulation and subsequent diffusion of atomic hydrogen into the metal. In the present study, platinum was implanted into high strength electroslag remelted (ESR) 4340 steel specimens to a dose of 10 16 atoms/cm 2. Both Pt-implanted and unimplanted specimens were rate charged with hydrogen. The relative concentration of diffusible hydrogen was determined using an electrochemical measurement device known as a Barnacle Electrode. The specimens implanted with platinum exhibited less diffusible hydrogen than the unimplanted steel. Slow strain rate notched-tensile tests, in an aqueous solution of 3.5 wt.% NaCI, were performed in order to evaluate the effect of hydrogen on strength and ductility. The Pt-implanted specimens were able to sustain significantly higher loads before fracture than their unimplanted counterparts. Scanning electron microscopy (SEM) verified the presence of brittle cracking typical of hydrogen embrittlement type failures. Degradation of mechanical properties due to hydrogen embrittlement was thus significantly reduced. This suggested that both the electrochemical and catalytic properties of the Pt-implanted surface were responsible for the improvement in properties.

  3. Effects of Calcination Condition on Porous Reduced Titanium Oxides and Oxynitrides via Preceramic Polymer Route

    SciTech Connect

    Hasegawa, George; Sato, Tatsuya; Kanamori, Kazuyoshi; Sun, Cheng-Jun; Ren, Yang; Kobayashi, Yoji; Kageyama, Hiroshi; Abe, Takeshi; Nakanishi, Kazuki

    2015-03-16

    The preceramic polymer route from titanium-based inorganic-organic hybrid networks provides electro conductive N-doped reduced titanium oxides (TinO2n–1) and titanium oxynitrides (TiOxNy) with a monolithic shape as well as well-defined porous structure. This methodology demonstrates advantageously lower temperature of crystal phase transition compared to the reduction of TiO2 by carbon or H2. In this study, effects of calcination condition on various features of the products have been explored by adopting three different atmospheric conditions and varying the calcination temperature. The detailed crystallographic and elemental analyses disclose the distinguished difference in phase transition behavior with respect to calcination atmosphere. Correlation between the crystallization and nitridation behaviors, porous properties and electric conductivities in the final products has been discussed.

  4. Bubble Generation in a Continuous Liquid Flow Under Reduced Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Pais, Salvatore Cezar

    1999-01-01

    The present work reports a study of bubble generation under reduced gravity conditions for both co-flow and cross-flow configurations. Experiments were performed aboard the DC-9 Reduced Gravity Aircraft at NASA Glenn Research Center, using an air-water system. Three different flow tube diameters were used: 1.27, 1.9, and 2.54 cm. Two different ratios of air injection nozzle to tube diameters were considered: 0.1 and 0.2. Gas and liquid volumetric flow rates were varied from 10 to 200 ml/s. It was experimentally observed that with increasing superficial liquid velocity, the bubbles generated decreased in size. The bubble diameter was shown to increase with increasing air injection nozzle diameters. As the tube diameter was increased, the size of the detached bubbles increased. Likewise, as the superficial liquid velocity was increased, the frequency of bubble formation increased and thus the time to detach forming bubbles decreased. Independent of the flow configuration (for either single nozzle or multiple nozzle gas injection), void fraction and hence flow regime transition can be controlled in a somewhat precise manner by solely varying the gas and liquid volumetric flow rates. On the other hand, it is observed that uniformity of bubble size can be controlled more accurately by using single nozzle gas injection than by using multiple port injection, since this latter system gives rise to unpredictable coalescence of adjacent bubbles. A theoretical model, based on an overall force balance, is employed to study single bubble generation in the dynamic and bubbly flow regime. Under conditions of reduced gravity, the gas momentum flux enhances bubble detachment; however, the surface tension forces at the nozzle tip inhibits bubble detachment. Liquid drag and inertia can act either as attaching or detaching force, depending on the relative velocity of the bubble with respect to the surrounding liquid. Predictions of the theoretical model compare well with performed

  5. Noradrenergic blockade of memory reconsolidation: a failure to reduce conditioned fear responding.

    PubMed

    Bos, Marieke Geerte Nynke; Beckers, Tom; Kindt, Merel

    2014-01-01

    Upon recall, a memory can enter a labile state in which it requires new protein synthesis to restabilize. This two-phased reconsolidation process raises the prospect to directly target excessive fear memory as opposed to the formation of inhibitory memory following extinction training. In our previous studies, we convincingly demonstrated that 40 mg propranolol HCl administration before or after memory reactivation eliminated the emotional expression of fear memory indexed by the fear potentiated startle reflex. To apply this procedure in clinical practice it is important to understand the optimal and boundary conditions of this procedure. As part of a large project aimed at unraveling putative boundary conditions of disrupting reconsolidation of associative fear memory with propranolol HCl, we again tested our memory reconsolidation procedure. Participants (N = 44) underwent a three-day differential fear conditioning procedure. Twenty-four hours after fear acquisition, participants received 40 mg propranolol HCl prior to memory reactivation. The next day, participants were subjected to extinction training and reinstatement testing. In sharp contrast to our previous findings, propranolol HCl before memory reactivation did not attenuate the startle fear response. Remarkably, the startle fear response even persisted during extinction training and did not show the usually observed gradual decline in conditioned physiological responding (startle potentiation and skin conductance) upon repeated unreinforced trials. We discuss these unexpected findings and propose some potential explanations. It remains, however, unclear why we observed a resistance to reduce conditioned fear responding by either disrupting reconsolidation or extinction training. The present results underscore that the success of human fear conditioning research may depend on subtle manipulations and instructions.

  6. Noradrenergic Blockade of Memory Reconsolidation: A Failure to Reduce Conditioned Fear Responding

    PubMed Central

    Bos, Marieke Geerte Nynke; Beckers, Tom; Kindt, Merel

    2014-01-01

    Upon recall, a memory can enter a labile state in which it requires new protein synthesis to restabilize. This two-phased reconsolidation process raises the prospect to directly target excessive fear memory as opposed to the formation of inhibitory memory following extinction training. In our previous studies, we convincingly demonstrated that 40 mg propranolol HCl administration before or after memory reactivation eliminated the emotional expression of fear memory indexed by the fear potentiated startle reflex. To apply this procedure in clinical practice it is important to understand the optimal and boundary conditions of this procedure. As part of a large project aimed at unraveling putative boundary conditions of disrupting reconsolidation of associative fear memory with propranolol HCl, we again tested our memory reconsolidation procedure. Participants (N = 44) underwent a three-day differential fear conditioning procedure. Twenty-four hours after fear acquisition, participants received 40 mg propranolol HCl prior to memory reactivation. The next day, participants were subjected to extinction training and reinstatement testing. In sharp contrast to our previous findings, propranolol HCl before memory reactivation did not attenuate the startle fear response. Remarkably, the startle fear response even persisted during extinction training and did not show the usually observed gradual decline in conditioned physiological responding (startle potentiation and skin conductance) upon repeated unreinforced trials. We discuss these unexpected findings and propose some potential explanations. It remains, however, unclear why we observed a resistance to reduce conditioned fear responding by either disrupting reconsolidation or extinction training. The present results underscore that the success of human fear conditioning research may depend on subtle manipulations and instructions. PMID:25506319

  7. Polycyclic Aromatic Hydrocarbon-Induced Changes in Bacterial Community Structure under Anoxic Nitrate Reducing Conditions

    PubMed Central

    Martirani-Von Abercron, Sophie-Marie; Pacheco, Daniel; Benito-Santano, Patricia; Marín, Patricia; Marqués, Silvia

    2016-01-01

    Although bacterial anaerobic degradation of mono-aromatic compounds has been characterized in depth, the degradation of polycyclic aromatic hydrocarbons (PAHs) such as naphthalene has only started to be understood in sulfate reducing bacteria, and little is known about the anaerobic degradation of PAHs in nitrate reducing bacteria. Starting from a series of environments which had suffered different degrees of hydrocarbon pollution, we used most probable number (MPN) enumeration to detect and quantify the presence of bacterial communities able to degrade several PAHs using nitrate as electron acceptor. We detected the presence of a substantial nitrate reducing community able to degrade naphthalene, 2-methylnaphthalene (2MN), and anthracene in some of the sites. With the aim of isolating strains able to degrade PAHs under denitrifying conditions, we set up a series of enrichment cultures with nitrate as terminal electron acceptor and PAHs as the only carbon source and followed the changes in the bacterial communities throughout the process. Results evidenced changes attributable to the imposed nitrate respiration regime, which in several samples were exacerbated in the presence of the PAHs. The presence of naphthalene or 2MN enriched the community in groups of uncultured and poorly characterized organisms, and notably in the Acidobacteria uncultured group iii1-8, which in some cases was only a minor component of the initial samples. Other phylotypes selected by PAHs in these conditions included Bacilli, which were enriched in naphthalene enrichments. Several nitrate reducing strains showing the capacity to grow on PAHs could be isolated on solid media, although the phenotype could not be reproduced in liquid cultures. Analysis of known PAH anaerobic degradation genes in the original samples and enrichment cultures did not reveal the presence of PAH-related nmsA-like sequences but confirmed the presence of bssA-like genes related to anaerobic toluene degradation

  8. Improved intensive care unit survival for critically ill allogeneic haematopoietic stem cell transplant recipients following reduced intensity conditioning

    PubMed Central

    Townsend, William M; Holroyd, Ailsa; Pearce, Rachel; Mackinnon, Stephen; Naik, Prakesh; Goldstone, Anthony H; Linch, David C; Peggs, Karl S; Thomson, Kirsty J; Singer, Mervyn; Howell, David C J; Morris, Emma C

    2013-01-01

    The use of allogeneic haematopoietic stem cell transplantation (Allo-HSCT) is a standard treatment option for many patients with haematological malignancies. Historically, patients requiring intensive care unit (ICU) admission for transplant-related toxicities have fared extremely poorly, with high ICU mortality rates. Little is known about the impact of reduced intensity Allo-HSCT conditioning regimens in older patients on the ICU and subsequent long-term outcomes. A retrospective analysis of data collected from 164 consecutive Allo-HSCT recipients admitted to ICU for a total of 213 admissions, at a single centre over an 11·5-year study period was performed. Follow-up was recorded until 31 March 2011. Autologous HSCT recipients were excluded. In this study we report favourable ICU survival following Allo-HSCT and, for the first time, demonstrate significantly better survival for patients who underwent Allo-HSCT with reduced intensity conditioning compared to those treated with myeloablative conditioning regimens. In addition, we identified the need for ventilation (invasive or non-invasive) as an independently significant adverse factor affecting short-term ICU outcome. For patients surviving ICU admission, subsequent long-term overall survival was excellent; 61% and 51% at 1 and 5 years, respectively. Reduced intensity Allo-HSCT patients admitted to ICU with critical illness have improved survival compared to myeloablative Allo-HSCT recipients. PMID:23496350

  9. Mechanisms of Chromium and Uranium Toxicity in Pseudomonas stutzeri RCH2 Grown under Anaerobic Nitrate-Reducing Conditions

    PubMed Central

    Thorgersen, Michael P.; Lancaster, W. Andrew; Ge, Xiaoxuan; Zane, Grant M.; Wetmore, Kelly M.; Vaccaro, Brian J.; Poole, Farris L.; Younkin, Adam D.; Deutschbauer, Adam M.; Arkin, Adam P.; Wall, Judy D.; Adams, Michael W. W.

    2017-01-01

    Chromium and uranium are highly toxic metals that contaminate many natural environments. We investigated their mechanisms of toxicity under anaerobic conditions using nitrate-reducing Pseudomonas stutzeri RCH2, which was originally isolated from a chromium-contaminated aquifer. A random barcode transposon site sequencing library of RCH2 was grown in the presence of the chromate oxyanion (Cr[VI]O42−) or uranyl oxycation (U[VI]O22+). Strains lacking genes required for a functional nitrate reductase had decreased fitness as both metals interacted with heme-containing enzymes required for the later steps in the denitrification pathway after nitrate is reduced to nitrite. Cr[VI]-resistance also required genes in the homologous recombination and nucleotide excision DNA repair pathways, showing that DNA is a target of Cr[VI] even under anaerobic conditions. The reduced thiol pool was also identified as a target of Cr[VI] toxicity and psest_2088, a gene of previously unknown function, was shown to have a role in the reduction of sulfite to sulfide. U[VI] resistance mechanisms involved exopolysaccharide synthesis and the universal stress protein UspA. As the first genome-wide fitness analysis of Cr[VI] and U[VI] toxicity under anaerobic conditions, this study provides new insight into the impact of Cr[VI] and U[VI] on an environmental isolate from a chromium contaminated site, as well as into the role of a ubiquitous protein, Psest_2088. PMID:28848534

  10. The solubility of platinum in silicate melt under reducing conditions: Results from experiments without metal inclusions

    NASA Astrophysics Data System (ADS)

    Bennett, N. R.; Brenan, J. M.; Koga, K. T.

    2014-05-01

    The solubility of Pt in silicate melt was investigated at conditions of 2073-2573 K, 2 GPa and ˜IW -1.5 to +3.5. These are the first measurements of Pt solubility under conditions more reducing than the iron-wüstite buffer (IW) which are demonstrably free from contamination by metal-inclusions. Pt solubility increases with increasing temperature and decreasing oxygen fugacity. The ability of carbon to enhance Pt solubility under reducing conditions (3500 K. Under these conditions however, the estimated Pt/Os ratio is ˜40,000 times higher than that estimated for the PUM (Brandon et al., 2006). Instead, the PUM composition is generated most readily by metal-silicate equilibrium at more modest temperatures (˜3100 K), followed by a late accretion of chondritic material subsequent to core formation.

  11. Method of reducing temperature in high-speed photography

    NASA Technical Reports Server (NTRS)

    Walker, E. D.; Slater, H. A.

    1984-01-01

    A continuing problem in high-speed motion picture photography is adequate lighting and the associated temperature rise. Large temperature rises can damage subject matter and make recording of the desired images impossible. The problem is more severe in macrophotography because of bellows extension and the necessary increase in light. This report covers one approach to reducing the initial temperature rise: the use of filters and heat-absorbing materials. The accompanying figures provide the starting point for selecting distance as a function of light intensity and determining the associated temperature rise. Using these figures will allow the photographer greater freedom in meeting different photographic situations.

  12. Extreme weather conditions reduce the CO2 fertilization effect in temperate C3 grasslands

    NASA Astrophysics Data System (ADS)

    Obermeier, Wolfgang; Lehnert, Lukas; Kammann, Claudia; Müller, Christoph; Grünhage, Ludger; Luterbacher, Jürg; Erbs, Martin; Yuan, Naiming; Bendix, Jörg

    2016-04-01

    The increase in atmospheric greenhouse gas concentrations from anthropogenic activities is the major driver of global climate change. The rising atmospheric carbon dioxide (CO2) concentrations may stimulate plant photosynthesis and, thus, cause a net sink effect in the global carbon cycle. As a consequence of an enhanced photosynthesis, an increase in the net primary productivity (NPP) of C3 plants (termed CO2 fertilization) is widely assumed. This process is associated with a reduced stomatal conductance of leaves as the carbon demand of photosynthesis is met earlier. This causes a higher water-use efficiency and, hence, may reduce water stress in plants exposed to elevated CO2 concentrations ([eCO2]). However, the magnitude and persistence of the CO2 fertilization effect under a future climate including more frequent weather extremes are controversial. To test the CO2 fertilization effect for Central European grasslands, a data set comprising 16 years of biomass samples and environmental variables such as local weather and soil conditions was analysed by means of a novel approach. The data set was recorded on a "Free Air Carbon dioxide Enrichment" (FACE) experimental site which allows to quantify the CO2 fertilization effect under naturally occurring climate variations. The results indicate that the CO2 fertilization effect on the aboveground biomass is strongest under local average environmental conditions. Such intermediate regimes were defined by the mean +/- 1 standard deviation of the long-term average in the respective variable three months before harvest. The observed CO2 fertilization effect was reduced or vanished under drier, wetter and hotter conditions when the respective variable exceeded the bounds of the intermediate regimes. Comparable conditions, characterized by a higher frequency of more extreme weather conditions, are predicted for the future by climate projections. Consequently, biogeochemical models may overestimate the future NPP sink

  13. Reduced prokaryotic heterotrophic production at in situ pressure conditions in the dark ocean

    NASA Astrophysics Data System (ADS)

    Amano-Sato, Chie; Sintes, Eva; Reinthaler, Thomas; Utsumi, Motoo; Herndl, Gerhard J.

    2017-04-01

    Prokaryotic heterotrophic production (PHP) is a key process in the ocean's biological carbon cycle. About 50% of the oceanic PHP takes place in the dark ocean characterized by low temperature and high hydrostatic pressure, which increases by 1 MPa (10 atm) every 100 m depth. However, rate measurements of PHP are usually performed under atmospheric pressure conditions. Yet, the difference in pressure conditions and the handling of the samples on board may introduce biases in the PHP measurements. To determine PHP at in situ conditions, we developed an in situ microbial incubator (ISMI) designed to autonomously sample and incubate seawater down to a depth of 4000 m. Natural prokaryotic communities from the North Atlantic and Pacific Oceans were incubated in the ISMI with 5 nM 3H-leucine at different depths ranging between 10 and 3200 m. For comparison, atmospheric pressure incubations at in situ temperature were also conducted. PHP and single cell activity assessed by microautoradiography combined with catalyzed reporter deposition fluorescence in situ hybridization (MICRO-CARD-FISH) were determined. PHP obtained under in situ pressure conditions was generally lower than under atmospheric pressure conditions, suggesting that incubation under atmospheric pressure on board stimulates activity of dark ocean prokaryotes. The ratio between the bulk PHP obtained under in situ and under atmospheric pressure conditions decreased with depth. Moreover, MICRO-CARD-FISH revealed that some specific prokaryotic groups are apparently more affected by the hydrostatic pressure condition than others. Our results suggest that PHP in the dark ocean might be lower than assumed based on measurements under surface pressure conditions.

  14. Nonreflective boundary conditions for high-order methods

    NASA Technical Reports Server (NTRS)

    Atkins, H.; Casper, Jay

    1994-01-01

    A different approach to nonreflective boundary conditions for the Euler equations is presented. This work is motivated by a need for inflow and outflow boundary conditions that do not limit the useful accuracy of high-order accurate methods. The primary interest is in the propagation and convection of continuous acoustic and convective waves. This new approach employs the exact solution to finite waves to relate interior values and ambient conditions to boundary values. The method is first presented in one dimension and then generalized to multidimensions. Grid refinement studies are used to demonstrate high-order convergence for both one-dimensional and two-dimensional flows.

  15. Nonreflective boundary conditions for high-order methods

    NASA Technical Reports Server (NTRS)

    Atkins, H. L.; Casper, Jay

    1993-01-01

    A different approach to nonreflective boundary conditions for the Euler equations is presented. This work is motivated by a need for in and outflow boundary conditions that do not limit the useful accuracy of high-order accurate methods. The primary interest is in the propagation and convection of continuous acoustic and convective waves. This new approach employs the exact solution to finite waves to relate interior values and ambient conditions to boundary values. The method is first presented in one dimension and then generalized to multidimensions. Grid refinement studies are used to demonstrate high-order convergence for both one-dimensional and two-dimensional flows.

  16. A high energy output nanogenerator based on reduced graphene oxide.

    PubMed

    Li, Weiping; Zhang, Yupeng; Liu, Liangliang; Li, Delong; Liao, Lei; Pan, Chunxu

    2015-11-21

    In this paper, we report a novel graphene-based nanogenerator for high energy harvesting. Experimental and theoretical results revealed that the energy output mechanism is the joint action of the strain effect (band engineering) and the triboelectric effect of reduced graphene oxide. It was found that the current could be adjusted by experimental parameters, such as the electrolyte concentration and rotation rate. Furthermore, the voltage output could be amplified by series connection of the system. Compared with other nanogenerators, the present graphene-based nanogenerator provides advantages, such as simple assembly, flexibility and high structural stability. It is expected that this nanogenerator will be of potential application in active sensors and sustainable power sources.

  17. Dissolution of Technetium(IV) Oxide by Natural and Synthetic Organic Ligands Under both Reducing and Oxidizing Conditions

    SciTech Connect

    Gu, Baohua; Dong, W.; Liang, Liyuan; Wall, Nathalie

    2011-01-01

    Technetium-99 (Tc) in nuclear waste is a significant environmental concern due to its long half-life and high mobility in the subsurface. Reductive precipitation of Tc(IV) oxides [TcO2(s)] is an effective means of immobilizing Tc, thereby impeding its migration in groundwater. However, TcO2(s) is subject to dissolution by oxidants and/or complexing agents. In this study we ascertain the effects of a synthetic organic ligand, ethylenediaminetetraacetate (EDTA), and two natural humic isolates on the dissolution and solubility of Tc(IV) oxides. Pure synthetic TcO2(s) (0.23 mM) was used in batch experiments to determine dissolution kinetics at pH ~6 under both reducing and oxidizing conditions. All organic ligands were found to enhance the dissolution of Tc(IV) oxides, increasing their solubility from ~10-8 M (without ligands) to 4 10-7 M under strictly anoxic conditions. Reduced Tc(IV) was also found to re-oxidize rapidly under oxic conditions, with an observed oxidative dissolution rate approximately an order of magnitude higher than that of ligand-promoted dissolution under reducing conditions. Significantly, oxidative dissolution was inhibited by EDTA but enhanced by humic acid compared with experiments without any complexing agents. The redox functional properties of humics, capable of facilitating intra-molecular electron transfer, may account for this increased oxidation rate under oxic conditions. Our results highlight the importance of complex interactions for the stability and mobility of Tc, and thus for the long-term fate of Tc in contaminated environments.

  18. Highly sensitive reduced graphene oxide microelectrode array sensor.

    PubMed

    Ng, Andrew M H; Kenry; Teck Lim, Chwee; Low, Hong Yee; Loh, Kian Ping

    2015-03-15

    Reduced graphene oxide (rGO) has been fabricated into a microelectrode array (MEA) using a modified nanoimprint lithography (NIL) technique. Through a modified NIL process, the rGO MEA was fabricated by a self-alignment of conducting Indium Tin Oxide (ITO) and rGO layer without etching of the rGO layer. The rGO MEA consists of an array of 10μm circular disks and microelectrode signature has been found at a pitch spacing of 60μm. The rGO MEA shows a sensitivity of 1.91nAμm(-1) to dopamine (DA) without the use of mediators or functionalization of the reduced graphene oxide (rGO) active layer. The performance of rGO MEA remains stable when tested under highly resistive media using a continuous flow set up, as well as when subjecting it to mechanical stress. The successful demonstration of NIL for fabricating rGO microelectrodes on flexible substrate presents a route for the large scale fabrication of highly sensitive, flexible and thin biosensing platform.

  19. Reduced graphene oxide film based highly responsive infrared detector

    NASA Astrophysics Data System (ADS)

    Khan, Mustaque A.; Nanda, Karuna K.; Krupanidhi, Saluru B.

    2017-08-01

    Due to the unique optical properties, graphene can effectively be used for the detection of infrared light. In this regard, reduced graphene oxide (RGO) has drawn considerable attention in scientific society because of simplicity of preparation and tunable properties. Here, we report the synthesis of RGO by solvothermal reduction of graphene oxide (GO) in ethanol and the detection of infrared light (1064 and 1550 nm) with metal—RGO—metal configuration. We have observed that photocurrent, responsivity as well as the external quantum efficiency increase with C/O ratio. The responsivity value in near-infrared region can be as high as 1.34 A · W-1 and the external quantum efficiency is more than 100%. Response times of these devices are in the order of few seconds. Overall, the responsivity of our device is found to be better than many of the already reported values where graphene or reduced graphene oxide is the only active material. The high value of quantum efficiency is due to strong light absorption and the presence of mid-gap states band in RGOs.

  20. Conditional Economic Incentives for Reducing HIV Risk Behaviors: Integration of Psychology and Behavioral Economics

    PubMed Central

    Operario, Don; Kuo, Caroline C.; Sosa-Rubí, Sandra G.; Gálarraga, Omar

    2014-01-01

    Objective This paper reviews psychology and behavioral economic approaches to HIV prevention, and examines the integration and application of these approaches in conditional economic incentive (CEI) programs for reducing HIV risk behavior. Methods We discuss the history of HIV prevention approaches, highlighting the important insights and limitations of psychological theories. We provide an overview of the theoretical tenets of behavioral economics that are relevant to HIV prevention, and utilize CEIs as an illustrative example of how traditional psychological theories end behavioral economics can be combined into new approaches for HIV prevention. Results Behavioral economic interventions can complement psychological frameworks for reducing HIV risk by introducing unique theoretical understandings about the conditions under which risky decisions are amenable to intervention. Findings from illustrative CEI programs show mixed but generally promising effects of economic interventions on HIV and STI prevalence, HIV testing, HIV medication adherence, and drug use. Conclusion CEI programs can complement psychological interventions for HIV prevention and behavioral risk reduction. To maximize program effectiveness, CEI programs must be designed according to contextual and population-specific factors that may determine intervention applicability and success. PMID:24001243

  1. Mass transport phenomena between bubbles and dissolved gases in liquids under reduced gravity conditions

    NASA Technical Reports Server (NTRS)

    Dewitt, Kenneth J.; Brockwell, Jonathan L.; Yung, Chain-Nan; Chai, An-Ti; Mcquillen, John B.; Sotos, Raymond G.; Neumann, Eric S.

    1988-01-01

    This paper will describe the experimental and analytical work that has been done to establish justification and feasibility for a Shuttle mid-deck experiment involving mass transfer between a gas bubble and a liquid. The experiment involves the observation and measurement of the dissolution of an isolated, immobile gas bubble of specified size and composition in a thermostatted solvent liquid of known concentration in the reduced gravity environment of earth orbit. Methods to generate and deploy the bubble have been successful both in normal gravity using mutually buoyant fluids and under reduced gravity conditions in the NASA Lear Jet. Initialization of the experiment with a bubble of a prescribed size and composition in a liquid of known concentration has been accomplished using the concept of unstable equilibrium. Subsequent bubble dissolution or growth is obtained by a step increase or decrease in the liquid pressure. A numerical model has been developed which simulates the bubble dynamics and can be used to determine molecular parameters by comparison with the experimental data. The primary objective of the experiment is the elimination of convective effects that occur in normal gravity. The results will yield information on transport under conditions of pure diffusion.

  2. Conditional economic incentives for reducing HIV risk behaviors: integration of psychology and behavioral economics.

    PubMed

    Operario, Don; Kuo, Caroline; Sosa-Rubí, Sandra G; Gálarraga, Omar

    2013-09-01

    This article reviews psychology and behavioral economic approaches to HIV prevention, and examines the integration and application of these approaches in conditional economic incentive (CEI) programs for reducing HIV risk behavior. We discuss the history of HIV prevention approaches, highlighting the important insights and limitations of psychological theories. We provide an overview of the theoretical tenets of behavioral economics that are relevant to HIV prevention, and utilize CEIs as an illustrative example of how traditional psychological theories and behavioral economics can be combined into new approaches for HIV prevention. Behavioral economic interventions can complement psychological frameworks for reducing HIV risk by introducing unique theoretical understandings about the conditions under which risky decisions are amenable to intervention. Findings from illustrative CEI programs show mixed but generally promising effects of economic interventions on HIV and sexually transmitted infection (STI) prevalence, HIV testing, HIV medication adherence, and drug use. CEI programs can complement psychological interventions for HIV prevention and behavioral risk reduction. To maximize program effectiveness, CEI programs must be designed according to contextual and population-specific factors that may determine intervention applicability and success. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  3. Mass transport phenomena between bubbles and dissolved gases in liquids under reduced gravity conditions

    NASA Technical Reports Server (NTRS)

    Dewitt, Kenneth J.; Brockwell, Jonathan L.; Yung, Chain-Nan; Chai, An-Ti; Mcquillen, John B.; Sotos, Raymond G.; Neumann, Eric S.

    1988-01-01

    This paper will describe the experimental and analytical work that has been done to establish justification and feasibility for a Shuttle mid-deck experiment involving mass transfer between a gas bubble and a liquid. The experiment involves the observation and measurement of the dissolution of an isolated, immobile gas bubble of specified size and composition in a thermostatted solvent liquid of known concentration in the reduced gravity environment of earth orbit. Methods to generate and deploy the bubble have been successful both in normal gravity using mutually buoyant fluids and under reduced gravity conditions in the NASA Lear Jet. Initialization of the experiment with a bubble of a prescribed size and composition in a liquid of known concentration has been accomplished using the concept of unstable equilibrium. Subsequent bubble dissolution or growth is obtained by a step increase or decrease in the liquid pressure. A numerical model has been developed which simulates the bubble dynamics and can be used to determine molecular parameters by comparison with the experimental data. The primary objective of the experiment is the elimination of convective effects that occur in normal gravity. The results will yield information on transport under conditions of pure diffusion.

  4. Inactivation of the lateral habenula reduces anxiogenic behavior and cocaine seeking under conditions of heightened stress.

    PubMed

    Gill, Margaret J; Ghee, Shannon M; Harper, Stiles M; See, Ronald E

    2013-10-01

    Recent anatomical and functional studies have renewed interest in the lateral habenula (LHb), a critical brain region that works in an opponent manner to modulate aversive and appetitive processes. In particular, increased LHb activation is believed to drive anxiogenic states during stressful conditions. Here, we reversibly inactivated the LHb with GABA receptor agonists (baclofen/muscimol) in rats prior to testing in an open field, elevated plus maze, and defensive burying task in the presence or absence of yohimbine, a noradrenergic α2-receptor antagonist that acts as an anxiogenic stressor. In a second set of experiments using a cocaine self-administration and reinstatement model, we inactivated the LHb during extinction responding and cue-induced reinstatement of cocaine seeking in the presence or absence of yohimbine pretreatment. Inactivation of the LHb after yohimbine treatment attenuated anxiogenic behavior by increasing time spent in the open arms and reducing the time spent burying. Inactivation of the LHb also reduced cocaine seeking when cue-induced reinstatement occurred in the presence of yohimbine, but did not affect extinction responding or cue-induced reinstatement by itself. These data demonstrate that the LHb critically regulates states of heightened anxiety during both unconditioned behavior and conditioned appetitive processes. Published by Elsevier Inc.

  5. Increasing concentrations of iron in surface waters as a consequence of reducing conditions in the catchment area

    NASA Astrophysics Data System (ADS)

    Ekström, Sara M.; Regnell, Olof; Reader, Heather E.; Nilsson, P. Anders; Löfgren, Stefan; Kritzberg, Emma S.

    2016-02-01

    Recent studies report trends of strongly increasing iron (Fe) concentrations in freshwaters. Since Fe is a key element with a decisive role in the biogeochemical cycling of major elements, it is important to understand the mechanisms behind these trends. We hypothesized that variations in Fe concentration are driven mainly by redox dynamics in hydraulically connected soils. Notably, Fe(III), which is the favored oxidation state except in environments where microbial activity provide strong reducing intensity, has several orders of magnitude lower water solubility than Fe(II). To test our hypothesis, seasonal variation in water chemistry, discharge, and air temperature was studied in three Swedish rivers. Methylmercury and sulfate were used as indicators of seasonal redox changes. Seasonal variability in water chemistry, discharge, and air temperature in the Emån and Lyckeby Rivers implied that the variation in Fe was primarily driven by the prevalence of reducing conditions in the catchment. In general, high Fe concentrations were observed when methylmercury was high and sulfate was low, indicative of reducing conditions. The Fe concentrations showed no or weak relationships with variations in dissolved organic matter concentration and aromaticity. The seasonal variation in Fe concentration of the Ume river was primarily dependent on timing of the snowmelt in high- versus low-altitude areas of the catchment. There were long-term trends of increasing temperature in all catchments and also trends of increasing discharge in the southern rivers, which should increase the probability for anaerobic conditions in space and time and thereby increase Fe transport to the aquatic systems.

  6. 15 CFR 14.14 - High risk special award conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false High risk special award conditions. 14.14 Section 14.14 Commerce and Foreign Trade Office of the Secretary of Commerce UNIFORM...-PROFIT, AND COMMERCIAL ORGANIZATIONS Pre-Award Requirements § 14.14 High risk special award...

  7. Structural stability of coprecipitated natural organic matter and ferric iron under reducing conditions

    USGS Publications Warehouse

    Henneberry, Yumiko K.; Kraus, Tamara E.C.; Nico, Peter S.; Horwath, William R.

    2012-01-01

    The objective was to assess the interaction of Fe coprecipitated with dissolved organic matter (DOM) and its effect on Fe (hydr)oxide crystallinity and DOM retention under abiotic reducing conditions. A Fe-based coagulant was reacted with DOM from an agricultural drain and the resulting precipitate (floc) was exposed to S(-II) and Fe(II). Solution concentrations of Fe(II/III) and DOM were monitored, floc crystallinity was determined using X-ray diffraction, and the composition and distribution of functional groups were assessed using scanning transmission X-ray microscopy (STXM) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. Results indicate coprecipitation of Fe(III) with DOM forms a non-crystalline floc that withstands crystallization regardless of change in pH, Fe:DOM ratio and type of reductant added. There was no evidence that exposure to reducing conditions led to release of DOM from the floc, indicating that coprecipitation with complex natural DOM in aquatic environments may stabilize Fe (hydr)oxides against crystallization upon reaction with reduced species and lead to long term sequestration of the DOM. STXM analysis identified spatially distinct regions with remarkable functional group purity, contrary to the model of DOM as a relatively uniform complex polymer lacking identifiable organic compounds. Polysaccharide-like OM was strongly and directly correlated with the presence of Fe but showed different Fe binding strength depending on the presence of carboxylic acid functional groups, whereas amide and aromatic functional groups were inversely correlated with Fe content.

  8. Methodology of high-resolution photography for mural condition database

    NASA Astrophysics Data System (ADS)

    Higuchi, R.; Suzuki, T.; Shibata, M.; Taniguchi, Y.

    2015-08-01

    Digital documentation is one of the most useful techniques to record the condition of cultural heritage. Recently, high-resolution images become increasingly useful because it is possible to show general views of mural paintings and also detailed mural conditions in a single image. As mural paintings are damaged by environmental stresses, it is necessary to record the details of painting condition on high-resolution base maps. Unfortunately, the cost of high-resolution photography and the difficulty of operating its instruments and software have commonly been an impediment for researchers and conservators. However, the recent development of graphic software makes its operation simpler and less expensive. In this paper, we suggest a new approach to make digital heritage inventories without special instruments, based on our recent our research project in Üzümlü church in Cappadocia, Turkey. This method enables us to achieve a high-resolution image database with low costs, short time, and limited human resources.

  9. Bulk Migration of Ni/NiO in Ni-YSZ during Reducing Conditions

    SciTech Connect

    Saraf, Laxmikant V.; Baer, Donald R.; Lea, Alan S.; Zhu, Zihua; Strohm, James J.; Sitzman, S. D.; King, David L.

    2010-02-09

    Understanding the migration of Ni/NiO in Ni-YSZ can potentially help to design a better solid oxide fuel cell (SOFC) anode. We have observed that extensive hydrogen reduction and methane steam reforming of Ni-YSZ caused bulk migration of Ni/NiO to at least ~ 5 µm deeper from the Ni-YSZ surface. No significant bulk migration effects were detected after simple thermal treatments in non-reducing/non-reforming environment. Surface analysis of a single zirconia grain in the first 10-20 nm region from annealed, hydrogen reduced and methane steam reformed Ni-YSZ shows Ni-enriched surface supporting earlier claims of Ni exsolution. 3D-EBSD analysis of thermally treated sample before exposing it to reducing and reforming environment indicated mixed NiO/YSZ phase with some porosity and random grain orientation. The surface analysis and mapping were carried out using ToF-SIMS and AES whereas EDS maps on FIB sliced areas on Ni-YSZ were utilized for the bulk analysis. The results provide additional information related to complex reactions occurring in SOFC during internal reforming conditions.

  10. The dual function of nitrite under stomach conditions is modulated by reducing compounds.

    PubMed

    Volk, J; Gorelik, S; Granit, R; Kohen, R; Kanner, J

    2009-09-01

    Salivary nitrite plays a role in the lipid peroxidation process of muscle tissue in simulated gastric fluid. The objectives of our study were to elucidate the fate of nitrite in the presence of reducing compounds and to evaluate its effect on lipid peroxidation during digestion. Nitrite at pH 3 (possibly NO(2.), not NO.) can oxidize beta-carotene, but the addition of reducing compounds, ascorbic acid or polyphenols, alters its effect. Ascorbic acid alone promoted the formation of NO. from nitrite only up to pH 3, but the addition of iron ions facilitated the formation of NO. up to pH 5.5. NO prevented membranal lipid peroxidation under stomach conditions. Nitrite, only in the presence of reducing compounds, achieved the same goal but at much higher concentrations. Addition of polyphenols to nitrite synergistically improved its antioxidant effect. Therefore, to promote NO. production and to achieve better control of the lipid peroxidation process in the stomach, a nitrite-rich meal should be consumed simultaneously with food rich in polyphenols.

  11. Degradation of Monochlorinated and Nonchlorinated Aromatic Compounds under Iron-Reducing Conditions

    PubMed Central

    Kazumi, J.; Haggblom, M. M.; Young, L. Y.

    1995-01-01

    The capacity for Fe(sup3+) to serve as an electron acceptor in the microbial degradation of monochlorinated and nonchlorinated aromatic compounds was investigated in anoxic sediment enrichments. The substrates tested included phenol, benzoate, aniline, their respective monochlorinated isomers, o-, m-, and p-cresol, and all six dimethylphenol isomers. Phenol and 2-, 3-, and 4-chlorophenol were utilized by anaerobic microorganisms, with the concomitant reduction of Fe(sup3+) to Fe(sup2+). The amount of Fe(sup2+) produced in the enrichments was 89 to 138% of that expected for the stoichiometric degradation of these substrates to CO(inf2), suggesting complete mineralization at the expense of Fe reduction. Under Fe-reducing conditions, there was initial loss of benzoate and 3-chlorobenzoate but not of 2- or 4-chlorobenzoate. In addition, there was initial microbial utilization of aniline but not of the chloroaniline isomers. There was also initial loss of o-, m-, and p-cresol in our enrichments. None of the dimethylphenol isomers, however, was degraded within 300 days. Furthermore, we tested the capacity of an Fe-reducing, benzoate-grown culture of Geobacter metallireducens GS-15 to utilize monochlorinated benzoates and phenols. G. metallireducens was able to degrade benzoate and phenol but none of their chlorinated isomers, suggesting that the degradation of chlorophenols in our sediment enrichments may be due to novel Fe-reducing organisms that have yet to be isolated. PMID:16535169

  12. Violation of eating expectancies does not reduce conditioned desires for chocolate.

    PubMed

    van den Akker, Karolien; van den Broek, Myrr; Havermans, Remco C; Jansen, Anita

    2016-05-01

    Although eating desires can be easily learned, their extinction appears more difficult. The present two-session study aimed to investigate the role of eating expectancies in the short and longer-term extinction of eating desires. In addition, the relationship between eating desires and conditioned evaluations was examined to test whether they might share a similar mechanism. It was hypothesized that the short-term extinction of eating desires would be more successful after the disconfirmation of eating expectancies (instructed extinction or IE), while resulting in worse longer-term extinction because omission of the food reward during extinction is not surprising. In contrast to the hypotheses, it was found that IE had no effect on the short-term and longer-term extinction of eating desires. Eating desires correlated with conditioned evaluations only to some extent. It is concluded that eating expectancies do not mediate the short-term extinction of conditioned eating desires. In addition, their longer-term extinction does not appear to be facilitated by a greater violation of eating expectancies. This suggests that it might not be necessary to focus on expectancy violation in cue exposure therapy to reduce eating desires. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Straw Mulching Reduces the Harmful Effects of Extreme Hydrological and Temperature Conditions in Citrus Orchards

    PubMed Central

    Liu, Yi; Wang, Jing; Liu, Dongbi; Li, Zhiguo; Zhang, Guoshi; Tao, Yong; Xie, Juan; Pan, Junfeng; Chen, Fang

    2014-01-01

    Extreme weather conditions with negative impacts can strongly affect agricultural production. In the Danjiangkou reservoir area, citrus yields were greatly influenced by cold weather conditions and drought stress in 2011. Soil straw mulching (SM) practices have a major effect on soil water and thermal regimes. A two-year field experiment was conducted to evaluate whether the SM practices can help achieve favorable citrus fruit yields. Results showed that the annual total runoff was significantly (P<0.05) reduced with SM as compared to the control (CK). Correspondingly, mean soil water storage in the top 100 cm of the soil profile was increased in the SM as compared to the CK treatment. However, this result was significant only in the dry season (Jan to Mar), and not in the wet season (Jul to Sep) for both years. Interestingly, the SM treatment did not significantly increase citrus fruit yield in 2010 but did so in 2011, when the citrus crop was completely destroyed (zero fruit yield) in the CK treatment plot due to extremely low temperatures during the citrus overwintering stage. The mulch probably acted as an insulator, resulting in smaller fluctuations in soil temperature in the SM than in the CK treatment. The results suggested that the small effects on soil water and temperature changes created by surface mulch had limited impact on citrus fruit yield in a normal year (e.g., in 2010). However, SM practices can positively impact citrus fruit yield in extreme weather conditions. PMID:24489844

  14. Dissolution of biogenic and synthetic UO2 under varied reducing conditions.

    PubMed

    Ulrich, Kai-Uwe; Singh, Abhas; Schofield, Eleanor J; Bargar, John R; Veeramani, Harish; Sharp, Jonathan O; Bernier-Latmani, Rizlan; Giammar, Daniel E

    2008-08-01

    The chemical stability of biogenic UO2, a nanoparticulate product of environmental bioremediation, may be impacted by the particles' surface free energy, structural defects, and compositional variability in analogy to abiotic UO(2+x) (0 < or = x < or = 0.25). This study quantifies and compares intrinsic solubility and dissolution rate constants of biogenic nano-UO2 and synthetic bulk UO2.00, taking molecular-scale structure into account. Rates were determined under anoxic conditions as a function of pH and dissolved inorganic carbon in continuous-flow experiments. The dissolution rates of biogenic and synthetic UO2 solids were lowest at near neutral pH and increased with decreasing pH. Similar surface area-normalized rates of biogenic and synthetic UO2 suggest comparable reactive surface site densities. This finding is consistent with the identified structural homology of biogenic UO2 and stoichiometric UO2.00 Compared to carbonate-free anoxic conditions, dissolved inorganic carbon accelerated the dissolution rate of biogenic UO2 by 3 orders of magnitude. This phenomenon suggests continuous surface oxidation of U(IV) to U(VI), with detachment of U(VI) as the rate-determining step in dissolution. Although reducing conditions were maintained throughout the experiments, the UO2 surface can be oxidized by water and radiogenic oxidants. Even in anoxic aquifers, UO2 dissolution may be controlled by surface U(VI) rather than U(IV) phases.

  15. Straw mulching reduces the harmful effects of extreme hydrological and temperature conditions in citrus orchards.

    PubMed

    Liu, Yi; Wang, Jing; Liu, Dongbi; Li, Zhiguo; Zhang, Guoshi; Tao, Yong; Xie, Juan; Pan, Junfeng; Chen, Fang

    2014-01-01

    Extreme weather conditions with negative impacts can strongly affect agricultural production. In the Danjiangkou reservoir area, citrus yields were greatly influenced by cold weather conditions and drought stress in 2011. Soil straw mulching (SM) practices have a major effect on soil water and thermal regimes. A two-year field experiment was conducted to evaluate whether the SM practices can help achieve favorable citrus fruit yields. Results showed that the annual total runoff was significantly (P<0.05) reduced with SM as compared to the control (CK). Correspondingly, mean soil water storage in the top 100 cm of the soil profile was increased in the SM as compared to the CK treatment. However, this result was significant only in the dry season (Jan to Mar), and not in the wet season (Jul to Sep) for both years. Interestingly, the SM treatment did not significantly increase citrus fruit yield in 2010 but did so in 2011, when the citrus crop was completely destroyed (zero fruit yield) in the CK treatment plot due to extremely low temperatures during the citrus overwintering stage. The mulch probably acted as an insulator, resulting in smaller fluctuations in soil temperature in the SM than in the CK treatment. The results suggested that the small effects on soil water and temperature changes created by surface mulch had limited impact on citrus fruit yield in a normal year (e.g., in 2010). However, SM practices can positively impact citrus fruit yield in extreme weather conditions.

  16. Evaluation of biotransformation products from 2,4-dinitrotoluene under nitrate-reducing conditions. Final report

    SciTech Connect

    Freedman, D.L.; Noguera, D.R.

    1995-04-10

    Wastewater generated during the manufacture of munitions often contains significant levels of nitrates and 2,4-dinitrotoluene (DNT). The objective of this project was to characterize the major biotransformation products formed from DNT under denitrifying conditions, and to identify the organisms responsible. In a denitrifying enrichment culture that used ethanol as the primary substrate, DNT was transformed primarily to 2-amino-4-nitrotoluene, 4-arnino-2-nitrotoluene, and 2,4-diaminotoluene. With extended incubation (>% 80 days), all of the 2,4-diaminotoluene subsequently disappeared. In cultures that received 14Cdnt, nearly all of the labeled metabolites remained in the aqueous phase. Approximately 35% consisted of insoluble material, while 29% was soluble hydrophobic and 32% was soluble hydrophilic. Two organisms were isolated from the enrichment: Pseudomonas aeruginosa and a much slower-growing rod. Pure cultures of P. aeruginosa only partially reduced DNT to 2,4-diaminotoluene under both aerobic and denitrifying conditions. Accumulation of 2-amino-4-nitrotoluene accounted for 25-45% of the DNT consumed, while 4-acetylamino-2-nitrotoluene accounted for 32-35%. Reduction and acetylation therefore appear to be major biotransformation pathways for DNT under both aerobic and denitrifying conditions.

  17. Developmental lead exposure impairs contextual fear conditioning and reduces adult hippocampal neurogenesis in the rat brain.

    PubMed

    Jaako-Movits, Külli; Zharkovsky, Tamara; Romantchik, Olga; Jurgenson, Monika; Merisalu, Eda; Heidmets, Lenne-Triin; Zharkovsky, Alexander

    2005-11-01

    The effects of developmental lead exposure on the emotional reactivity, contextual fear conditioning and neurogenesis in the dentate gyrus of 60-80 days-old rats were studied. Wistar rat pups were exposed to 0.2% lead acetate via their dams' drinking water from postnatal day (PND) 1 to PND 21 and directly via drinking water from weaning until PND 30. At PND 60 and 80 the level of anxiety and contextual fear conditioning were studied, respectively. At PND 80 all animals received injections of BrdU to determine the effects of Pb on the generation of new cells in the dentate gyrus of hippocampus and on their survival and differentiation patterns. The results of the present study demonstrate that developmental lead exposure induces persistent increase in the level of anxiety and inhibition of contextual fear conditioning. Developmental lead exposure reduced generation of new cells in the dentate gyrus and altered the pattern of differentiation of BrdU-positive cells into mature neurons. A lower proportion of BrdU-positive cells co-expressed with the marker for mature neurons, calbindin. In contrast, the proportions of young not fully differentiated neurons and proportions of astroglial cells, generated from newly born cells, were increased in lead-exposed animals. Our results demonstrate that developmental lead exposure induces persistent inhibition of neurogenesis and alters the pattern of differentiation of newly born cells in the dentate gyrus of rat hippocampus, which could, at least partly, contribute to behavioral and cognitive impairments observed in adulthood.

  18. Case Management Reduces Drinking During Pregnancy among High Risk Women

    PubMed Central

    May, Philip A.; Marais, Anna-Susan; Gossage, J. Phillip; Barnard, Ronel; Joubert, Belinda; Cloete, Marise; Hendricks, Natalie; Roux, Sumien; Blom, Annalien; Steenekamp, Jeanetta; Alexander, Theresa; Andreas, Romena; Human, Suzanne; Snell, Cudore; Seedat, Soraya; Parry, Charles C.; Kalberg, Wendy O.; Buckley, David; Blankenship, Jason

    2014-01-01

    Aim Estimate the efficacy of Case Management (CM) for women at high risk for bearing a child with Fetal Alcohol Spectrum Disorders (FASD). Design Women were recruited from antenatal clinics and engaged in 18 months of CM. Setting A South African community with a subculture of heavy, regular, weekend, recreational drinking and high documented rates of FASD. Participants Forty-one women who were high risk for bearing a child with FASD. Measures Statistical analysis of trends in drinking and other risk factors. Findings At intake 87.8% were pregnant, most had previous alcohol-exposed pregnancies, most/all of their friends drink alcohol (67.5%), and 50.0% had stressful lives. CM was particularly valuable for pregnant women, as statistically significant reductions in alcohol risk were obtained for them in multiple variables: total drinks on weekends after six months of CM (p = .026) and estimated peak blood alcohol concentration (BAC) at six (p < .001) and 18 months (p < .001). For participants completing 18 months of CM, AUDIT scores improved significantly by 6-month follow-up (from 19.8 to 9.7, p = .000), and even though rising at 12 and 18 months, AUDIT scores indicate that problematic drinking remained statistically significantly lower than baseline throughout CM. Happiness scale scores correlated significantly with reduced drinking in most time periods. Conclusions An enduring change in drinking behavior is difficult in this social setting. Yet, CM provided by skilled and empathic case managers reduced maternal drinking at critical times, and therefore, alcohol exposure levels to the fetus. PMID:24729823

  19. Abiotic Formation of Valine Peptides Under Conditions of High Temperature and High Pressure

    NASA Astrophysics Data System (ADS)

    Furukawa, Yoshihiro; Otake, Tsubasa; Ishiguro, Takato; Nakazawa, Hiromoto; Kakegawa, Takeshi

    2012-12-01

    We investigated the oligomerization of solid valine and the stabilities of valine and valine peptides under conditions of high temperature (150-200 °C) and high pressure (50-150 MPa). Experiments were performed under non-aqueous condition in order to promote dehydration reaction. After prolonged exposure of monomeric valine to elevated temperatures and pressures, the products were analyzed by liquid chromatography mass spectrometry comparing their retention times and masses. We identified linear peptides that ranged in size from dimer to hexamer, as well as a cyclic dimer. Previous studies that attempted abiotic oligomerization of valine in the absence of a catalyst have never reported valine peptides larger than a dimer. Increased reaction temperature increased the dissociative decomposition of valine and valine peptides to products such as glycine, β-alanine, ammonia, and amines by processes such as deamination, decarboxylation, and cracking. The amount of residual valine and peptide yields was greater at higher pressures at a given temperature, pressure, and reaction time. This suggests that dissociative decomposition of valine and valine peptides is reduced by pressure. Our findings are relevant to the investigation of diagenetic processes in prebiotic marine sediments where similar pressures occur under water-poor conditions. These findings also suggest that amino acids, such as valine, could have been polymerized to peptides in deep prebiotic marine sediments within a few hundred million years.

  20. Baclofen, raclopride, and naltrexone differentially reduce solid fat emulsion intake under limited access conditions.

    PubMed

    Rao, R E; Wojnicki, F H E; Coupland, J; Ghosh, S; Corwin, R L W

    2008-06-01

    Previous work in rats has demonstrated that an Intermittent (Monday, Wednesday, Friday) schedule of access promotes binge-type consumption of 100% vegetable shortening during a 1-h period of availability. The present study used novel shortening-derived stable solid emulsions of various fat concentrations. These emulsions were the consistency of pudding and did not demonstrate oil and water phase separation previously reported with oil-based liquid emulsions. Male Sprague-Dawley rats were grouped according to schedule of access (Daily or Intermittent) to one of three concentrations (18%, 32%, 56%) of solid fat emulsion. There were no significant Intermittent vs. Daily differences in amount consumed, due to high intakes in all groups. This indicated the acceptability of the emulsions. Baclofen (GABA(B) agonist) and raclopride (D2-like antagonist) both significantly reduced emulsion intake in all Daily groups, but only in the 56% fat Intermittent group. Naltrexone (opioid antagonist), in contrast, significantly reduced 32% and 56% fat emulsion intake in the Intermittent, as well as the Daily groups. These results indicate that the fat intake-reducing effects of GABA(B) activation and D(2) blockade depend upon fat concentration and schedule of fat access, while the fat intake-reducing effects of opioid blockade depend upon fat concentration but not schedule of access.

  1. BACLOFEN, RACLOPRIDE, AND NALTREXONE DIFFERENTIALLY REDUCE SOLID FAT EMULSION INTAKE UNDER LIMITED ACCESS CONDITIONS

    PubMed Central

    RE, Rao; FHE, Wojnicki; J, Coupland; S, Ghosh; RLW, Corwin

    2009-01-01

    Previous work in rats has demonstrated that an Intermittent (Monday, Wednesday, Friday) schedule of access promotes binge-type consumption of 100% vegetable shortening during a 1-hour period of availability. The present study used novel shortening-derived stable solid emulsions of various fat concentrations. These emulsions were the consistency of pudding and did not demonstrate oil and water phase separation previously reported with oil-based liquid emulsions. Male Sprague-Dawley rats were grouped according to schedule of access (Daily or Intermittent) to one of three concentrations (18%, 32%, 56%) of solid fat emulsion. There were no significant Intermittent vs. Daily differences in amount consumed, due to high intakes in all groups. This indicated the acceptability of the emulsions. Baclofen (GABA-B agonist) and raclopride (D2-like antagonist) both significantly reduced emulsion intake in all Daily groups, but only in the 56% fat Intermittent group. Naltrexone (opioid antagonist), in contrast, significantly reduced 32% and 56% fat emulsion intake in the Intermittent, as well as the Daily groups. These results indicate that the fat intake reducing effects of GABAB activation and D2 blockade depend upon fat concentration and schedule of fat access, while the fat intake reducing effects of opioid blockade depend upon fat concentration but not schedule of access. PMID:18353432

  2. Conditional Disabled-1 Deletion in Mice Alters Hippocampal Neurogenesis and Reduces Seizure Threshold

    PubMed Central

    Korn, Matthew J.; Mandle, Quinton J.; Parent, Jack M.

    2016-01-01

    Many animal models of temporal lobe epilepsy (TLE) exhibit altered neurogenesis arising from progenitors within the dentate gyrus subgranular zone (SGZ). Aberrant integration of new neurons into the existing circuit is thought to contribute to epileptogenesis. In particular, adult-born neurons that exhibit ectopic migration and hilar basal dendrites (HBDs) are suggested to be pro-epileptogenic. Loss of reelin signaling may contribute to these morphological changes in patients with epilepsy. We previously demonstrated that conditional deletion of the reelin adaptor protein, disabled-1 (Dab1), from postnatal mouse SGZ progenitors generated dentate granule cells (DGCs) with abnormal dendritic development and ectopic placement. To determine whether the early postnatal loss of reelin signaling is epileptogenic, we conditionally deleted Dab1 in neural progenitors and their progeny on postnatal days 7–8 and performed chronic video-EEG recordings 8–10 weeks later. Dab1-deficient mice did not have spontaneous seizures but exhibited interictal epileptiform abnormalities and a significantly reduced latency to pilocarpine-induced status epilepticus. After chemoconvulsant treatment, over 90% of mice deficient for Dab1 developed generalized motor convulsions with tonic-clonic movements, rearing, and falling compared to <20% of wild-type mice. Recombination efficiency, measured by Cre reporter expression, inversely correlated with time to the first sustained seizure. These pro-epileptogenic changes were associated with decreased neurogenesis and increased numbers of hilar ectopic DGCs. Interestingly, neurons co-expressing the Cre reporter comprised a fraction of these hilar ectopic DGCs cells, suggesting a non-cell autonomous effect for the loss of reelin signaling. We also noted a dispersion of the CA1 pyramidal layer, likely due to hypomorphic effects of the conditional Dab1 allele, but this abnormality did not correlate with seizure susceptibility. These findings suggest

  3. Reducing conditions can alter the source of respired carbon and stimulate decomposition in mineral soils

    NASA Astrophysics Data System (ADS)

    Huang, W.; Hall, S. J.

    2016-12-01

    Soil organic matter decomposition is widely thought to be constrained by reducing conditions in flooded wetland ecosystems. However, the potential impact of periodic reducing conditions on carbon (C) mineralization in terrestrial mineral soils that experience transient moisture saturation has received less attention. Here we incubated three Mollisols amended with C4 leaf litter at three different soil moisture levels (field capacity for the control, intermediate, and saturation) over three months in the laboratory. Soil CO2 and CH4 production and isotope ratios of CO2 (δ13CO2) were measured daily using a tunable diode laser for the first two weeks and weekly thereafter. Soil Eh dropped from 516 mV to -184 mV in the intermediate and saturated soils during the first seventeen days; iron (Fe) reduction occurred in both intermediate and saturated soils after the seventh day. Total CO2 production rate in the intermediate and saturated soils was initially lower than the control, but exceeded the control after the eleventh day. After three months, mean cumulative CO2 production was significantly higher in the intermediate soil moisture treatment (152 μmol CO2 g-1 soil, P < 0.01) and equivalent between the saturated and control soils (128 and 141 μmol CO2 g-1 soil, P = 0.11). The intermediate and saturated soils also induced substantial CH4 production. Differences in mean δ13CO2 (-14.0‰ for the control and -22.7‰ for the saturated soils) over the first two weeks (before CH4 production began) showed that CO2 production from the saturated soils was derived from different C source(s) compared to the control. These findings challenge traditional paradigms by showing that reducing conditions can enhance C mineralization, perhaps by facilitating microbial access to alternative or occluded C sources. We suggest that Fe reduction could be an important mechanism of C loss in mineral soils due to the release of adsorbed or co-precipitated organic matter during Fe

  4. Dual design resistor for high voltage conditioning and transmission lines

    DOEpatents

    Siggins, Timothy Lynn [Newport News, VA; Murray, Charles W [Hayes, VA; Walker, Richard L [Norfolk, VA

    2007-01-23

    A dual resistor for eliminating the requirement for two different value resistors. The dual resistor includes a conditioning resistor at a high resistance value and a run resistor at a low resistance value. The run resistor can travel inside the conditioning resistor. The run resistor is capable of being advanced by a drive assembly until an electrical path is completed through the run resistor thereby shorting out the conditioning resistor and allowing the lower resistance run resistor to take over as the current carrier.

  5. Mechanism of reduced cardiac stroke volume at high altitude.

    PubMed

    Alexander, J K; Grover, R F

    1983-06-01

    Two postulates have been advanced to account for reduced stroke at high altitude: (1) diminished venous return secondary to contracted plasma volume and (2) left ventricular (LV) dysfunction secondary to hypoxia. To test these hypotheses, we assessed LV dimensions and contractility indices by M-mode echocardiography and systolic time intervals in 11 young men at sealevel and serially for 10 days at 3100 m altitude. Mean LV end-diastolic dimension fell 16% after 6-8 days, with a 20% decrease in plasma volume reflected by hematocrit rise. Pre-ejection period to LV ejection time (PEP/LVET) ratio was increased after 1-2 days. All indices of contractility were unchanged at rest, and slightly enhanced during exercise. Thus stroke volume falls and PEP/LVET ratio rises at 3100 m because of diminished venous return despite preservation of LV systolic performance.

  6. Soil structure, colloids, and chemical transport as affected by short-term reducing conditions: a laboratory study

    USDA-ARS?s Scientific Manuscript database

    Upland soils in the Midwestern US often undergo reducing conditions when soils are temporally flooded during the spring and remain water saturated for days or weeks. Short-term reducing conditions change the chemistry of the soil and may affect soil structure and solution chemical transport. The eff...

  7. Fault gouge rheology under confined, high-velocity conditions

    NASA Astrophysics Data System (ADS)

    Reches, Z.; Madden, A. S.; Chen, X.

    2012-12-01

    We recently developed the experimental capability to investigate the shear properties of fine-grain gouge under confined conditions and high-velocity. The experimental system includes a rotary apparatus that can apply large displacements of tens of meters, slip velocity of 0.001- 2.0 m/s, and normal stress of 35 MPa (Reches and Lockner, 2010). The key new component is a Confined ROtary Cell (CROC) that can shear a gouge layer either dry or under pore-pressure. The pore pressure is controlled by two syringe pumps. CROC includes a ring-shape gouge chamber of 62.5 mm inner diameter, 81.25 mm outer diameter, and up to 3 mm thick gouge sample. The lower, rotating part of CROC contains the sample chamber, and the upper, stationary part includes the loading, hollow cylinder and setting for temperature, and dilation measurements, and pore-pressure control. Each side of the gouge chamber has two pairs of industrial, spring-energized, self-lubricating, teflon-graphite seals, built for particle media and can work at temperature up to 250 ded C. The space between each of the two sets of seals is pressurized by nitrogen. This design generates 'zero-differential pressure' on the inner seal (which is in contact with the gouge powder), and prevents gouge leaks. For the preliminary dry experiments, we used ~2.0 mm thick layers of room-dry kaolinite powder. Total displacements were on the order of meters and normal stress up to 4 MPa. The initial shear was accommodated by multiple internal slip surfaces within the kaolinite layer accommodated as oriented Riedel shear structures. Later, the shear was localized within a thin, plate-parallel Y-surface. The kaolinite layer was compacted at a quasi-asymptotic rate, and displayed a steady-state friction coefficient of ~ 0.5 with no clear dependence on slip velocity up to 0.15 m/s. Further experiments with loose quartz sand (grain size ~ 125 micron) included both dry runs and pore-pressure (distilled water) controlled runs. The sand was

  8. High-albedo materials for reducing building cooling energy use

    SciTech Connect

    Taha, H.; Sailor, D.; Akbari, H.

    1992-01-01

    One simple and effective way to mitigate urban heat islands, i.e., the higher temperatures in cities compared to those of the surrounds, and their negative impacts on cooling energy consumption is to use high-albedo materials on major urban surfaces such as rooftops, streets, sidewalks, school yards, and the exposed surfaces of parking lots. High-albedo materials can save cooling energy use by directly reducing the heat gain through a building`s envelope (direct effect) and also by lowering the urban air temperature in the neighborhood of the building (indirect effect). This project is an attempt to address high-albedo materials for buildings and to perform measurements of roof coatings. We search for existing methods and materials to implement fighter colors on major building and urban surfaces. Their cost effectiveness are examined and the possible related technical, maintenance, and environmental problems are identified. We develop a method for measuring albedo in the field by studying the instrumentation aspects of such measurements. The surface temperature impacts of various albedo/materials in the actual outdoor environment are studied by measuring the surface temperatures of a variety of materials tested on an actual roof. We also generate an albedo database for several urban surfaces to serve as a reference for future use. The results indicate that high-albedo materials can have a large impact on the surface temperature regime. On clear sunny days, when the solar noon surface temperatures of conventional roofing materials were about 40{degrees}C (72{degrees}F) warmer than air, the surface temperature of high-albedo coatings were only about 5{degrees}C warmer than air. In the morning and in the late afternoon, the high-albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0.055{degrees}C/(W m{sup {minus}2}), the high-albedo surfaces warm up by an average 0.015{degrees}C/(W m{sup {minus}2}).

  9. High-albedo materials for reducing building cooling energy use

    SciTech Connect

    Taha, H.; Sailor, D.; Akbari, H.

    1992-01-01

    One simple and effective way to mitigate urban heat islands, i.e., the higher temperatures in cities compared to those of the surrounds, and their negative impacts on cooling energy consumption is to use high-albedo materials on major urban surfaces such as rooftops, streets, sidewalks, school yards, and the exposed surfaces of parking lots. High-albedo materials can save cooling energy use by directly reducing the heat gain through a building's envelope (direct effect) and also by lowering the urban air temperature in the neighborhood of the building (indirect effect). This project is an attempt to address high-albedo materials for buildings and to perform measurements of roof coatings. We search for existing methods and materials to implement fighter colors on major building and urban surfaces. Their cost effectiveness are examined and the possible related technical, maintenance, and environmental problems are identified. We develop a method for measuring albedo in the field by studying the instrumentation aspects of such measurements. The surface temperature impacts of various albedo/materials in the actual outdoor environment are studied by measuring the surface temperatures of a variety of materials tested on an actual roof. We also generate an albedo database for several urban surfaces to serve as a reference for future use. The results indicate that high-albedo materials can have a large impact on the surface temperature regime. On clear sunny days, when the solar noon surface temperatures of conventional roofing materials were about 40{degrees}C (72{degrees}F) warmer than air, the surface temperature of high-albedo coatings were only about 5{degrees}C warmer than air. In the morning and in the late afternoon, the high-albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0.055{degrees}C/(W m{sup {minus}2}), the high-albedo surfaces warm up by an average 0.015{degrees}C/(W m{sup {minus}2}).

  10. Aqueous Dissolution of Silver Iodide and Associated Iodine Release Under Reducing Conditions with Sulfide

    SciTech Connect

    Yaohiro Inagaki; Toshitaka Imamura; Kazuya Idemitsu; Tatsumi Arima; Osamu Kato; Hidekazu Asano; Tsutomu Nishimura

    2007-07-01

    Aqueous dissolution tests of silver iodide (AgI) were performed in Na{sub 2}S solutions in order to evaluate, empirically, dissolution of AgI to release iodine under reducing conditions with sulfide. The results indicated that AgI dissolves to release iodine being controlled by mainly precipitation of Ag{sub 2}S. However, the dissolution of AgI can be depressed to proceed, and the thermodynamic equilibrium cannot be attained easily. Solid phase analysis for the reacted AgI suggested that a thin layer of solid silver forming at AgI surface may evolve to be protective against transportation of reactant species, which can lead to the depression in the dissolution of AgI. (authors)

  11. A new system to reduce formaldehyde levels improves safety conditions during gross veterinary anatomy learning.

    PubMed

    Nacher, Víctor; Llombart, Cristina; Carretero, Ana; Navarro, Marc; Ysern, Pere; Calero, Sebastián; Fígols, Enric; Ruberte, Jesús

    2007-01-01

    Dissection is a very useful method of learning veterinary anatomy. However, formaldehyde, which is widely used to preserve cadavers, is an irritant, and it has recently been classified as a carcinogen. In 1997, the Instituto Nacional de Seguridad e Higiene en el Trabajo [National Institute of Workplace Security and Hygiene] found that the levels of formaldehyde in our dissection room were above the threshold limit values. Unfortunately, no optimal substitute for formaldehyde is currently available. Therefore, we designed a new ventilation system that combines slow propulsion of fresh air from above the dissection table and rapid aspiration of polluted air from the perimeter. Formaldehyde measurements performed in 2004, after the introduction of this new system into our dissection laboratory, showed a dramatic reduction (about tenfold, or 0.03 ppm). A suitable propelling/aspirating air system successfully reduces the concentration of formaldehyde in the dissection room, significantly improving safety conditions for students, instructors, and technical staff during gross anatomy learning.

  12. Blood circulation in rat lungs under conditions of reduced oxygen level in inhaled air.

    PubMed

    Ivanov, K P; Mel'nikova, N N

    2012-12-01

    According to some authors, reduction in oxygen level in the lung alveoli results in constriction of afferent vessels, while others observed no vessel constriction. The issue is of principle importance in relation to the lung involvement in body adaptation to hypoxia. Conventional methods are inefficient to solve it, therefore we used a contact microscope allowing observation of lung circulatory system structure and condition of the lung circulatory system in whole, virtually intact animal, on whole undamaged lungs in situ, at normal physiological lung position in the thorax. We found that large vessels carrying blood to the alveoli do not constrict or dilate at reduced Po(2)in lung alveoli. These vessels with a diameter of 15 to 40 μ and more are the only blood source for alveoli.

  13. Outcome after Transplantation According to Reduced-Intensity Conditioning Regimen in Patients Undergoing Transplantation for Myelofibrosis.

    PubMed

    Robin, Marie; Porcher, Raphael; Wolschke, Christine; Sicre de Fontbrune, Flore; Alchalby, Haefaa; Christopeit, Maximilian; Cassinat, Bruno; Zabelina, Tatjana; Peffault de Latour, Régis; Ayuk, Francis; Socié, Gérard; Kröger, Nicolaus

    2016-07-01

    Allogeneic hematopoietic stem cell transplantation remains the sole curative option for myelofibrosis. Many transplantation recipients receive a reduced-intensity conditioning (RIC) regimen owing to age or comorbidities; however, there is little published evidence to guide the choice of RIC regimen. In this study, we compared outcomes in patients who received 1 of 2 frequently used RIC regimens for patients with myelofibrosis: fludarabine-busulfan (FB) and fludarabine-melphalan (FM). A total of 160 patients underwent a RIC allograft procedure (FB group, n = 105; FM group, n = 55). We have developed a complex statistical model involving weighting and adjustment to permit comparison between these 2 groups. After weighting, the incidence of acute graft-versus-host disease (GVHD) was 62% in the FM group and 31% in the FB group (P = .001), and the corresponding incidence of chronic GVHD was 49% and 53%, respectively. The 7-year progression-free survival was were 52% in the FM group versus 33% in the FB group, and the 7-year overall survival rate 52% in the FM group versus 59% in the FB group. Nonrelapse mortality (NRM) was 43% in the FM group and 31% in the FB group. Multivariable analyses revealed no significant differences in PFS between the 2 groups; however, the relapse rate was significantly lower in the FM group (hazard ratio, 9.21; P = .008), whereas a trend toward reduced NRM was seen in the FB group (hazard ratio, 0.51; P = .068). In conclusion, both regimens appear to be efficient in mediating disease control and can be used to successfully condition patients with myelofibrosis. The FM regimen appears to induce more NRM than the FB regimen, but with augmented control of disease, leading to comparable overall survival rates for both regimens. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  14. Biperiden (an M1 antagonist) reduces memory consolidation of cocaine-conditioned place preference.

    PubMed

    Zacarias, Marina S; Ramos, Anna C; Alves, Danielle R; Galduróz, José C F

    2012-04-04

    It is well-known that cocaine dependence is a public health issue, and several studies stress the need to look for new and more effective treatments. Although the mesolimbic dopamine (DA) system, which originates in the ventral tegmental area (VTA) and projects to several forebrain structures, is known to be critically involved in the neurobiology of cocaine dependence, acetylcholine (ACh) has also been shown to play an important role in cocaine dependence via its action on this reward system. ACh is also important in the formation of hippocampal memory associated with appetitive behavior. Thus, the aim of this study was to evaluate the effect of biperiden, an ACh antagonist with high affinity for muscarinic M1 type receptors, on the acquisition of cocaine-conditioned place preference (CPP) in mice. The cocaine and biperiden were dissolved in sterile saline and were administered intraperitoneally at a dose of 10mg/kg. The conditioning regime was 8 days long, and the cholinergic antagonist was given immediately at the end of each conditioning session. The test for CPP occurred 24h after the last session. The results showed that animals treated with biperiden spent significantly less time in the cocaine-paired compartment than did the ones treated with saline. This finding represents a reduction in the consolidation of cocaine-induced CPP. One hypothesis that could explain this outcome focuses on the action of cholinergic antagonists on the consolidation of contextual memories. The amnesic effect of M1 antagonists on aversive tasks and on morphine CPP has been demonstrated when administered before the training or the conditioning session. The present study highlights the possibility of impairment in the acquisition of an appetitive memory, even when the cholinergic drug is administered after the conditioning session. This protocol also rejects the possibility of performance disturbance and suggests a possible pharmacological tool in the treatment of cocaine

  15. Changes in iso- and n-alkane distribution during biodegradation of crude oil under nitrate and sulphate reducing conditions.

    PubMed

    Hasinger, Marion; Scherr, Kerstin E; Lundaa, Tserennyam; Bräuer, Leopold; Zach, Clemens; Loibner, Andreas Paul

    2012-02-20

    Crude oil consists of a large number of hydrocarbons with different susceptibility to microbial degradation. The influence of hydrocarbon structure and molecular weight on hydrocarbon biodegradation under anaerobic conditions is not fully explored. In this study oxygen, nitrate and sulphate served as terminal electron acceptors (TEAs) for the microbial degradation of a paraffin-rich crude oil in a freshly contaminated soil. During 185 days of incubation, alkanes from n-C11 to n-C39, three n- to iso-alkane ratios commonly used as weathering indicators and the unresolved complex mixture (UCM) were quantified and statistically analyzed. The use of different TEAs for hydrocarbon degradation resulted in dissimilar degradative patterns for n- and iso-alkanes. While n-alkane biodegradation followed well-established patterns under aerobic conditions, lower molecular weight alkanes were found to be more recalcitrant than mid- to high-molecular weight alkanes under nitrate-reducing conditions. Biodegradation with sulphate as the TEA was most pronounced for long-chain (n-C32 to n-C39) alkanes. The observation of increasing ratios of n-C17 to pristane and of n-C18 to phytane provides first evidence of the preferential degradation of branched over normal alkanes under sulphate reducing conditions. The formation of distinctly different n- and iso-alkane biodegradation fingerprints under different electron accepting conditions may be used to assess the occurrence of specific degradation processes at a contaminated site. The use of n- to iso-alkane ratios for this purpose may require adjustment if applied for anaerobic sites. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. New Results in Two-Phase Pressure Drop Calculations at Reduced Gravity Conditions

    NASA Astrophysics Data System (ADS)

    Braisted, Jon; Kurwitz, Cable; Best, Frederick

    2004-02-01

    The mass, power, and volume energy savings of two-phase systems for future spacecraft creates many advantages over current single-phase systems. Current models of two-phase phenomena such as pressure drop, void fraction, and flow regime prediction are still not well defined for space applications. Commercially available two-phase modeling software has been developed for a large range of acceleration fields including reduced-gravity conditions. Recently, a two-phase experiment has been flown to expand the two-phase database. A model of the experiment was created in the software to determine how well the software could predict the pressure drop observed in the experiment. Of the simulations conducted, the computer model shows good agreement of the pressure drop in the experiment to within 30%. However, the software does begin to over-predict pressure drop in certain regions of a flow regime map indicating that some models used in the software package for reduced-gravity modeling need improvement.

  17. Mass transport phenomena between bubbles and dissolved gases in liquids under reduced gravity conditions

    NASA Technical Reports Server (NTRS)

    Dewitt, Kenneth J.; Brockwell, Jonathan L.; Yung, Chain-Nan; Chai, An-Ti; Mcquillen, John B.; Sotos, Raymond G.; Neumann, Eric S.

    1988-01-01

    The experimental and analytical work that was done to establish justification and feasibility for a shuttle middeck experiment involving mass transfer between a gas bubble and a liquid is described. The experiment involves the observation and measurement of the dissolution of an isolated immobile gas bubble of specified size and composition in a thermostatted solvent liquid of known concentration in the reduced gravity environment of earth orbit. Methods to generate and deploy the bubble were successful both in normal gravity using mutually buoyant fluids and under reduced gravity conditions in the NASA Lear Jet. Initialization of the experiment with a bubble of a prescribed size and composition in a liquid of known concentration was accomplished using the concept of unstable equilibrium. Subsequent bubble dissolution or growth is obtained by a step increase or decrease in the liquid pressure. A numerical model was developed which simulates the bubble dynamics and can be used to determine molecular parameters by comparison with the experimental data. The primary objective of the experiment is the elimination of convective effects that occur in normal gravity.

  18. Isolation and Characterization of an Enterobacter cloacae Strain That Reduces Hexavalent Chromium under Anaerobic Conditions

    PubMed Central

    Wang, Pi-Chao; Mori, Tsukasa; Komori, Kohya; Sasatsu, Masanori; Toda, Kiyoshi; Ohtake, Hisao

    1989-01-01

    An Enterobacter cloacae strain (HO1) capable of reducing hexavalent chromium (chromate) was isolated from activated sludge. This bacterium was resistant to chromate under both aerobic and anaerobic conditions. Only the anaerobic culture of the E. cloacae isolate showed chromate reduction. In the anaerobic culture, yellow turned white with chromate and the turbidity increased as the reduction proceeded, suggesting that insoluble chromium hydroxide was formed. E. cloacae is likely to utilize toxic chromate as an electron acceptor anaerobically because (i) the anaerobic growth of E. cloacae HO1 accompanied the decrease of toxic chromate in culture medium, (ii) the chromate-reducing activity was rapidly inhibited by oxygen, and (iii) the reduction occurred more rapidly in glycerol- or acetate-grown cells than in glucose-grown cells. The chromate reduction in E. cloacae HO1 was observed at pH 6.0 to 8.5 (optimum pH, 7.0) and at 10 to 40°C (optimum, 30°C). PMID:16347962

  19. High duck nesting success in a predator-reduced environment

    USGS Publications Warehouse

    Duebbert, H.F.; Lokemoen, J.T.

    1980-01-01

    Duck nesting and production were studied during 1969-74 on a 51-ha field of undisturbed grass-legume cover and a surrounding 8.13-km2 area in north-central South Dakota. The principal mammalian predators of ducks were reduced within a 259-km2 zone from May 1969 through August 1971. Dabbling duck nest densities, hatching success, and breeding populations attained high levels. Seven duck species produced 1,062 nests on the 51-ha field during 6 years, 864 (81%) hatched, 146 (14%) were destroyed, and 52 (5%) had other fates. During 1970-72, when predator reduction was most effective, the hatching success for 756 nests was 94%. The number of mallard (Anas platyrhynchos) nests increased from 37 (0.7/ha) in 1969 to 181 (3.5/ha) in 1972. Mallard pairs increased from 2.8/km2 to 16.8/km2 on the 8.13-km2 area during the same period. A minimum of 7,250 ducklings hatched on the 51-ha field during the 6 years, including 2,342 ducklings in 1972. Exceptionally high duck nesting densities and hatching rates occurred when predators were controlled.

  20. High abundance and diversity of iron-reducing bacteria in wet tropical forest soils

    NASA Astrophysics Data System (ADS)

    Dubinsky, E. A.; Brodie, E. L.; Andersen, G. L.; Silver, W. L.; Firestone, M. K.

    2005-12-01

    In wet tropical forests, warm and damp conditions promote rapid oxygen consumption in soils that contain high concentrations of iron oxides. Ferric iron is often the most abundant terminal electron acceptor for bacteria in soil during frequent periods of oxygen depletion. Highly-weathered soils of the wet tropics are likely to support large populations of Fe(III) reducing microorganisms whose activity is consequential to soil mineralogy and geochemistry. We studied the diversity and abundance of Fe(III)-reducing bacteria along a 700 m elevation gradient with variable soil redox conditions in northeast Puerto Rico. Culturable iron-reducers were enumerated, isolated and identified using five different media that contained poorly-crystalline Fe(III) oxides as the terminal electron acceptor. Entire soil microbial communities were characterized along the gradient using high-density 16S rRNA gene microarrays capable of detecting 9000 different bacterial and archaeal taxa and assessing changes in their spatial abundance. Fe(III)-reducing bacteria spanned the Proteobacteria and Firmicutes and included many previously unidentified Fe(III) reducers. Populations of culturable iron reducers numbered 108 to 1010 bacteria per gram soil, some of the highest numbers found in any soils or sediments, and population size increased significantly with elevation. These bacteria were dominated by both unclassified alpha- and gamma proteobacteria not previously known to reduce iron, in addition to delta-proteobacteria, such as the family Geobacteraceae, that are well-known Fe(III) reducers. The activity of this group of bacteria can affect biogeochemical cycles that are linked to iron and fundamental to tropical forest productivity, including phosphorus and carbon cycling.

  1. Effect of oxalic acid treatment on sediment arsenic concentrations and lability under reducing conditions.

    PubMed

    Sun, Jing; Bostick, Benjamin C; Mailloux, Brian J; Ross, James M; Chillrud, Steven N

    2016-07-05

    Oxalic acid enhances arsenic (As) mobilization by dissolving As host minerals and competing for sorption sites. Oxalic acid amendments thus could potentially improve the efficiency of widely used pump-and-treat (P&T) remediation. This study investigates the effectiveness of oxalic acid on As mobilization from contaminated sediments with different As input sources and redox conditions, and examines whether residual sediment As after oxalic acid treatment can still be reductively mobilized. Batch extraction, column, and microcosm experiments were performed in the laboratory using sediments from the Dover Municipal Landfill and the Vineland Chemical Company Superfund sites. Oxalic acid mobilized As from both Dover and Vineland sediments, although the efficiency rates were different. The residual As in both Dover and Vineland sediments after oxalic acid treatment was less vulnerable to microbial reduction than before the treatment. Oxalic acid could thus improve the efficiency of P&T. X-ray absorption spectroscopy analysis indicated that the Vineland sediment samples still contained reactive Fe(III) minerals after oxalic acid treatment, and thus released more As into solution under reducing conditions than the treated Dover samples. Therefore, the efficacy of enhanced P&T must consider sediment Fe mineralogy when evaluating its overall potential for remediating groundwater As. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Effect of Oxalic Acid Treatment on Sediment Arsenic Concentrations and Lability under Reducing Conditions

    PubMed Central

    Sun, Jing; Bostick, Benjamin C.; Mailloux, Brian J.; Ross, James M.; Chillrud, Steven N.

    2016-01-01

    Oxalic acid enhances arsenic (As) mobilization by dissolving As host minerals and competing for sorption sites. Oxalic acid amendments thus could potentially improve the efficiency of widely used pump-and-treat (P&T) remediation. This study investigates the effectiveness of oxalic acid on As mobilization from contaminated sediments with different As input sources and redox conditions, and examines whether residual sediment As after oxalic acid treatment can still be reductively mobilized. Batch extraction, column, and microcosm experiments were performed in the laboratory using sediments from the Dover Municipal Landfill and the Vineland Chemical Company Superfund sites. Oxalic acid mobilized As from both Dover and Vineland sediments, although the efficiency rates were different. The residual As in both Dover and Vineland sediments after oxalic acid treatment was less vulnerable to microbial reduction than before the treatment. Oxalic acid could thus improve the efficiency of P&T. X-ray absorption spectroscopy analysis indicated that the Vineland sediment samples still contained reactive Fe(III) minerals after oxalic acid treatment, and thus released more As into solution under reducing conditions than the Dover samples. Therefore, the efficacy of P&T must consider sediment Fe mineralogy when evaluating its overall potential for remediating groundwater As. PMID:26970042

  3. Real-Time NMR Studies of Oxyamine Ligations of Reducing Carbohydrates under Equilibrium Conditions.

    PubMed

    Baudendistel, Oliver R; Wieland, Daniel E; Schmidt, Magnus S; Wittmann, Valentin

    2016-11-21

    Ligation reactions at the anomeric center of carbohydrates have gained increasing importance in the field of glycobiology. Oxyamines are frequently used in labeling, immobilization, and bioconjugation of reducing carbohydrates. Herein, we present a systematic investigation of these ligation reactions under aqueous conditions. A series of four unprotected monosaccharides (glucose, N-acetylglucosamine, mannose, and 2-deoxyglucose) and one disaccharide (N,N'-diacetylchitobiose) was reacted with three primary and one secondary oxyamine. We monitored the concentrations of the starting materials and products by (1) H NMR spectroscopy and determined reaction times and equilibrium yields. Our experiments show that the outcome of the ligation reaction is not only dependent on the sugar and oxyamine used but also strongly on the reaction conditions. In the case of glucose, lowering the pH from 6 to 3 led to steadily increasing reaction rates, whereas the yields were decreasing at the same time. Variation of the temperature did not only influence the product ratio in equilibrium but can also have a strong impact on the equilibrium yield. In the case of reactions of a primary oxyamine, increased temperatures led to a higher proportion of acyclic products. Reaction of the secondary oxyamine with glucose unexpectedly led to lower yields at higher temperatures. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Linked Redox Precipitation of Sulfur and Selenium under Anaerobic Conditions by Sulfate-Reducing Bacterial Biofilms

    PubMed Central

    Hockin, Simon L.; Gadd, Geoffrey M.

    2003-01-01

    A biofilm-forming strain of sulfate-reducing bacteria (SRB), isolated from a naturally occurring mixed biofilm and identified by 16S rDNA analysis as a strain of Desulfomicrobium norvegicum, rapidly removed 200 μM selenite from solution during growth on lactate and sulfate. Elemental selenium and elemental sulfur were precipitated outside SRB cells. Precipitation occurred by an abiotic reaction with bacterially generated sulfide. This appears to be a generalized ability among SRB, arising from dissimilatory sulfide biogenesis, and can take place under low redox conditions and in the dark. The reaction represents a new means for the deposition of elemental sulfur by SRB under such conditions. A combination of transmission electron microscopy, environmental scanning electron microscopy, and cryostage field emission scanning electron microscopy were used to reveal the hydrated nature of SRB biofilms and to investigate the location of deposited sulfur-selenium in relation to biofilm elements. When pregrown SRB biofilms were exposed to a selenite-containing medium, nanometer-sized selenium-sulfur granules were precipitated within the biofilm matrix. Selenite was therefore shown to pass through the biofilm matrix before reacting with bacterially generated sulfide. This constitutes an efficient method for the removal of toxic concentrations of selenite from solution. Implications for environmental cycling and the fate of sulfur and selenium are discussed, and a general model for the potential action of SRB in selenium transformations is presented. PMID:14660350

  5. Experimental cooling during incubation leads to reduced innate immunity and body condition in nestling tree swallows.

    PubMed

    Ardia, Daniel R; Pérez, Jonathan H; Clotfelter, Ethan D

    2010-06-22

    Nest microclimate can have strong effects that can carry over to later life-history stages. We experimentally cooled the nests of tree swallows (Tachycineta bicolor). Females incubating in cooled nests reduced incubation time and allowed egg temperatures to drop, leading to extended incubation periods. We partially cross-fostered nestlings to test carry-over effects of cooling during incubation on nestling innate constitutive immunity, assessed through bacteria killing ability (BKA) of blood. Nestlings that had been cooled as eggs showed a lower ability to kill bacteria than control nestlings, regardless of the treatment of their foster mother. However, there was no effect of treatment of rearing females on nestling BKA in control nestlings, even though cooled females made significantly fewer feeding visits than did control females. This suggests that the effect of cooling occurred during incubation and was not due to carry-over effects on nestling condition. Nestlings that were exposed to experimental cooling as embryos had lower residual body mass and absolute body mass at all four ages measured. Our results indicate that environmental conditions and trade-offs experienced during one stage of development can have important carry-over effects on later life-history stages.

  6. Experimental cooling during incubation leads to reduced innate immunity and body condition in nestling tree swallows

    PubMed Central

    Ardia, Daniel R.; Pérez, Jonathan H.; Clotfelter, Ethan D.

    2010-01-01

    Nest microclimate can have strong effects that can carry over to later life-history stages. We experimentally cooled the nests of tree swallows (Tachycineta bicolor). Females incubating in cooled nests reduced incubation time and allowed egg temperatures to drop, leading to extended incubation periods. We partially cross-fostered nestlings to test carry-over effects of cooling during incubation on nestling innate constitutive immunity, assessed through bacteria killing ability (BKA) of blood. Nestlings that had been cooled as eggs showed a lower ability to kill bacteria than control nestlings, regardless of the treatment of their foster mother. However, there was no effect of treatment of rearing females on nestling BKA in control nestlings, even though cooled females made significantly fewer feeding visits than did control females. This suggests that the effect of cooling occurred during incubation and was not due to carry-over effects on nestling condition. Nestlings that were exposed to experimental cooling as embryos had lower residual body mass and absolute body mass at all four ages measured. Our results indicate that environmental conditions and trade-offs experienced during one stage of development can have important carry-over effects on later life-history stages. PMID:20147326

  7. Bone Marrow or Peripheral Blood for Reduced-Intensity Conditioning Unrelated Donor Transplantation

    PubMed Central

    Eapen, Mary; Logan, Brent R.; Horowitz, Mary M.; Zhong, Xiaobo; Perales, Miguel-Angel; Lee, Stephanie J.; Rocha, Vanderson; Soiffer, Robert J.; Champlin, Richard E.

    2015-01-01

    Purpose There have been no randomized trials that have compared peripheral blood (PB) with bone marrow (BM) grafts in the setting of reduced-intensity conditioning (RIC) transplantations for hematologic malignancy. Because immune modulation plays a significant role in sustaining clinical remission after RIC, we hypothesize that higher graft-versus-host disease (GVHD) associated with PB transplantation may offer a survival advantage. Patients and Methods The primary outcome evaluated was overall survival. Cox regression models were built to study outcomes after transplantation of PB (n = 887) relative to BM (n = 219) for patients with acute myeloid leukemia, myelodysplastic syndrome, or non-Hodgkin lymphoma, the three most common indications for unrelated RIC transplantation. Transplantations were performed in the United States between 2000 and 2008. Conditioning regimens consisted of an alkylating agent and fludarabine, and GVHD prophylaxis involved a calcineurin inhibitor (CNI) with either methotrexate (MTX) or mycophenolate mofetil (MMF). Results After adjusting for age, performance score, donor-recipient HLA-match, disease, and disease status at transplantation (factors associated with overall survival), there were no significant differences in 5-year rates of survival after transplantation of PB compared with BM: 34% versus 38% with CNI-MTX and 27% versus 20% with CNI-MMF GVHD prophylaxis. Conclusion Survival after transplantation of PB and BM are comparable in the setting of nonirradiation RIC regimens for hematologic malignancy. The effect of GVHD prophylaxis on survival merits further evaluation. PMID:25534391

  8. Bone marrow or peripheral blood for reduced-intensity conditioning unrelated donor transplantation.

    PubMed

    Eapen, Mary; Logan, Brent R; Horowitz, Mary M; Zhong, Xiaobo; Perales, Miguel-Angel; Lee, Stephanie J; Rocha, Vanderson; Soiffer, Robert J; Champlin, Richard E

    2015-02-01

    There have been no randomized trials that have compared peripheral blood (PB) with bone marrow (BM) grafts in the setting of reduced-intensity conditioning (RIC) transplantations for hematologic malignancy. Because immune modulation plays a significant role in sustaining clinical remission after RIC, we hypothesize that higher graft-versus-host disease (GVHD) associated with PB transplantation may offer a survival advantage. The primary outcome evaluated was overall survival. Cox regression models were built to study outcomes after transplantation of PB (n = 887) relative to BM (n = 219) for patients with acute myeloid leukemia, myelodysplastic syndrome, or non-Hodgkin lymphoma, the three most common indications for unrelated RIC transplantation. Transplantations were performed in the United States between 2000 and 2008. Conditioning regimens consisted of an alkylating agent and fludarabine, and GVHD prophylaxis involved a calcineurin inhibitor (CNI) with either methotrexate (MTX) or mycophenolate mofetil (MMF). After adjusting for age, performance score, donor-recipient HLA-match, disease, and disease status at transplantation (factors associated with overall survival), there were no significant differences in 5-year rates of survival after transplantation of PB compared with BM: 34% versus 38% with CNI-MTX and 27% versus 20% with CNI-MMF GVHD prophylaxis. Survival after transplantation of PB and BM are comparable in the setting of nonirradiation RIC regimens for hematologic malignancy. The effect of GVHD prophylaxis on survival merits further evaluation. © 2014 by American Society of Clinical Oncology.

  9. Cotinine enhances the extinction of contextual fear memory and reduces anxiety after fear conditioning.

    PubMed

    Zeitlin, Ross; Patel, Sagar; Solomon, Rosalynn; Tran, John; Weeber, Edwin J; Echeverria, Valentina

    2012-03-17

    Posttraumatic stress disorder (PTSD) is an anxiety disorder triggered by traumatic events. Symptoms include anxiety, depression and deficits in fear memory extinction (FE). PTSD patients show a higher prevalence of cigarette smoking than the general population. The present study investigated the effects of cotinine, a tobacco-derived compound, over anxiety and contextual fear memory after fear conditioning (FC) in mice, a model for inducing PTSD-like symptoms. Two-month-old C57BL/6J mice were separated into three experimental groups. These groups were used to investigate the effect of pretreatment with cotinine on contextual fear memory and posttreatment on extinction and stability or retrievability of the fear memory. Also, changes induced by cotinine on the expression of extracellular signal-regulated kinase (ERK)1/2 were assessed after extinction in the hippocampus. An increase in anxiety and corticosterone levels were found after fear conditioning. Cotinine did not affect corticosterone levels but enhanced the extinction of contextual fear, decreased anxiety and the stability and/or retrievability of contextual fear memory. Cotinine-treated mice showed higher levels of the active forms of ERK1/2 than vehicle-treated mice after FC. This evidence suggests that cotinine is a potential new pharmacological treatment to reduce symptoms in individuals with PTSD.

  10. Linked redox precipitation of sulfur and selenium under anaerobic conditions by sulfate-reducing bacterial biofilms.

    PubMed

    Hockin, Simon L; Gadd, Geoffrey M

    2003-12-01

    A biofilm-forming strain of sulfate-reducing bacteria (SRB), isolated from a naturally occurring mixed biofilm and identified by 16S rDNA analysis as a strain of Desulfomicrobium norvegicum, rapidly removed 200 micro M selenite from solution during growth on lactate and sulfate. Elemental selenium and elemental sulfur were precipitated outside SRB cells. Precipitation occurred by an abiotic reaction with bacterially generated sulfide. This appears to be a generalized ability among SRB, arising from dissimilatory sulfide biogenesis, and can take place under low redox conditions and in the dark. The reaction represents a new means for the deposition of elemental sulfur by SRB under such conditions. A combination of transmission electron microscopy, environmental scanning electron microscopy, and cryostage field emission scanning electron microscopy were used to reveal the hydrated nature of SRB biofilms and to investigate the location of deposited sulfur-selenium in relation to biofilm elements. When pregrown SRB biofilms were exposed to a selenite-containing medium, nanometer-sized selenium-sulfur granules were precipitated within the biofilm matrix. Selenite was therefore shown to pass through the biofilm matrix before reacting with bacterially generated sulfide. This constitutes an efficient method for the removal of toxic concentrations of selenite from solution. Implications for environmental cycling and the fate of sulfur and selenium are discussed, and a general model for the potential action of SRB in selenium transformations is presented.

  11. Conditional Deletion of Ferritin H in Mice Reduces B and T Lymphocyte Populations

    PubMed Central

    Vanoaica, Liviu; Richman, Larry; Jaworski, Maike; Darshan, Deepak; Luther, Sanjiv A.; Kühn, Lukas C.

    2014-01-01

    The immune system and iron availability are intimately linked as appropriate iron supply is needed for cell proliferation, while excess iron, as observed in hemochromatosis, may reduce subsets of lymphocytes. We have tested the effects of a ferritin H gene deletion on lymphocytes. Mx-Cre mediated conditional deletion of ferritin H in bone marrow reduced the number of mature B cells and peripheral T cells in all lymphoid organs. FACS analysis showed an increase in the labile iron pool, enhanced reactive oxygen species formation and mitochondrial depolarization. The findings were confirmed by a B-cell specific deletion using Fthlox/lox; CD19-Cre mice. Mature B cells were strongly under-represented in bone marrow and spleen of the deleted mice, whereas pre-B and immature B cells were not affected. Bone marrow B cells showed increased proliferation as judged by the number of cells in S and G2/M phase as well as BrdU incorporation. Upon in vitro culture with B-cell activating factor of the tumor necrosis factor family (BAFF), ferritin H-deleted spleen B cells showed lower survival rates than wild type cells. This was partially reversed with iron-chelator deferiprone. The loss of T cells was also confirmed by a T cell-specific deletion in Fthlox/lox;CD4-Cre mice. Our data show that ferritin H is required for B and T cell survival by actively reducing the labile iron pool. They further suggest that natural B and T cell maturation is influenced by intracellular iron levels and possibly deregulated in iron excess or deprivation. PMID:24586648

  12. The use of magnesium peroxide for the inhibition of sulfate-reducing bacteria under anoxic conditions.

    PubMed

    Chang, Yu-Jie; Chang, Yi-Tang; Hung, Chun-Hsiung

    2008-11-01

    Sulfate-reducing bacteria (SRB), which cause microbiologically influenced material corrosion under anoxic conditions, form one of the major groups of microorganisms responsible for the generation of hydrogen sulfide. In this study, which is aimed at reducing the presence of SRB, a novel alternative approach involving the addition of magnesium peroxide (MgO2) compounds involving the use of reagent-grade MgO2 and a commercial product (ORC) was evaluated as a means of inhibiting SRB in laboratory batch columns. Different concentrations of MgO2 were added in the columns when black sulfide sediment had appeared in the columns. The experimental results showed that MgO2 is able to inhibit biogenic sulfide. The number of SRB, the sulfide concentration and the sulfate reducing rate (SRR) were decreased. ORCtrade mark as an additive was able to decrease more effectively the concentration of sulfide in water and the SRB-control effect was maintained over a longer time period when ORCtrade mark was used. The level of oxidation-reduction potential (ORP), which has a linear relationship to the sulfide/sulfate ratio, is a good indicator of SRB activity. As determined by fluorescence in-situ hybridization (FISH), most SRB growth was inhibited under increasing amounts of added MgO2. The concentration of sulfide reflected the abundance of the SRB. Utilization of organic matter greater than the theoretical SRB utilization rate indicated that facultative heterotrophs became dominant after MgO2 was added. The results of this study could supply the useful information for further study on evaluating the solution to biocorrosion problems in practical situations.

  13. A case study employing operant conditioning to reduce stress of capture for red-bellied tamarins (Saguinus labiatus).

    PubMed

    Owen, Yvonne; Amory, Jonathan R

    2011-01-01

    Traditional techniques used to capture New World monkeys, such as net capture, can induce high levels of acute stress detrimental to welfare. Alternatively, training nonhuman animals via operant conditioning to voluntarily participate in husbandry and/or veterinary practices is accepted as a humane process that can reduce stress and improve welfare. This study details the use of operant conditioning using positive reinforcement training (PRT) and target training to train a family of 5 captive red-bellied tamarins (Saguinus labiatus) in a wildlife park to voluntarily enter a transportation box and remain calm for 1 min after 54 training sessions. Observations of 2 unrelated net-capture processes provided measures of locomotion and vocalizations as indicators of stress behavior that were compared with those of the trained tamarins. Net-captured monkeys exhibited rapid erratic locomotion and emitted long, high-frequency vocalizations during capture whereas the trained tamarins exhibited minimal locomotion and emitted only 4 brief vocalizations (root mean square 35 dB) during capture. This indicates that the use of PRT considerably reduced potential for stress and improved welfare during the capture and containment of the tamarins. Copyright © Taylor & Francis Group, LLC

  14. LLMapReduce: Multi-Level Map-Reduce for High Performance Data Analysis

    DTIC Science & Technology

    2016-05-23

    Lexington, MA, U.S.A Abstract— The map-reduce parallel programming model has become extremely popular in the big data community. Many big data ...to big data users running on a supercomputer. LLMapReduce dramatically simplifies map-reduce programming by providing simple parallel programming...SLURM; LSF I. INTRODUCTION Large scale computing is currently dominated by four ecosystems: supercomputing, database, enterprise, and big data [1

  15. The ecophysiology of sulfur isotope fractionation by sulfate reducing bacteria in response to variable environmental conditions

    NASA Astrophysics Data System (ADS)

    Leavitt, W.; Bradley, A. S.; Johnston, D. T.; Pereira, I. A. C.; Venceslau, S.; Wallace, C.

    2014-12-01

    Microbial sulfate reducers (MSR) drive the Earth's biogeochemical sulfur cycle. At the heart of this energy metabolism is a cascade of redox transformations coupling organic carbon and/or hydrogen oxidation to the dissimilatory reduction of sulfate to sulfide. The sulfide produced is depleted in the heavier isotopes of sulfur relative to sulfate. The magnitude of discrimination (fractionation) depends on: i) the cell-specific sulfate reduction rate (csSRR, Kaplan & Rittenberg (1964) Can. J. Microbio.; Chambers et al. (1975) Can. J. Microbio; Sim et al. (2011) GCA; Leavitt et al. (2013) PNAS), ii) the ambient sulfate concentration (Harrison & Thode (1958) Research; Habicht et al. (2002) Science; Bradley et al. in review), iii) both sulfate and electron donor availability, or iv) an intrinsic physiological limitation (e.g. cellular division rate). When neither sulfate nor electron donor limits csSRR a more complex function relates the magnitude of isotope fractionation to cell physiology and environmental conditions. In recent and on-going work we have examined the importance of enzyme-specific fractionation factors, as well as the influence of electron donor or electron acceptor availability under carefully controlled culture conditions (e.g. Leavitt et al. (2013) PNAS). In light of recent advances in MSR genetics and biochemistry we utilize well-characterized mutant strains, along with a continuous-culture methodology (Leavitt et al. (2013) PNAS) to further probe the fractionation capacity of this metabolism under controlled physiological conditions. We present our latest findings on the magnitude of S and D/H isotope fractionation in both wild type and mutant strains. We will discuss these in light of recent theoretical advances (Wing & Halevy (2014) PNAS), examining the mode and relevance of MSR isotope fractionation in the laboratory to modern and ancient environmental settings, particularly anoxic marine sediments.

  16. Studies of Two-Phase Flow Dynamics and Heat Transfer at Reduced Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Witte, Larry C.; Bousman, W. Scott; Fore, Larry B.

    1996-01-01

    The ability to predict gas-liquid flow patterns is crucial to the design and operation of two-phase flow systems in the microgravity environment. Flow pattern maps have been developed in this study which show the occurrence of flow patterns as a function of gas and liquid superficial velocities as well as tube diameter, liquid viscosity and surface tension. The results have demonstrated that the location of the bubble-slug transition is affected by the tube diameter for air-water systems and by surface tension, suggesting that turbulence-induced bubble fluctuations and coalescence mechanisms play a role in this transition. The location of the slug-annular transition on the flow pattern maps is largely unaffected by tube diameter, liquid viscosity or surface tension in the ranges tested. Void fraction-based transition criteria were developed which separate the flow patterns on the flow pattern maps with reasonable accuracy. Weber number transition criteria also show promise but further work is needed to improve these models. For annular gas-liquid flows of air-water and air- 50 percent glycerine under reduced gravity conditions, the pressure gradient agrees fairly well with a version of the Lockhart-Martinelli correlation but the measured film thickness deviates from published correlations at lower Reynolds numbers. Nusselt numbers, based on a film thickness obtained from standard normal-gravity correlations, follow the relation, Nu = A Re(sup n) Pr(exp l/3), but more experimental data in a reduced gravity environment are needed to increase the confidence in the estimated constants, A and n. In the slug flow regime, experimental pressure gradient does not correlate well with either the Lockhart-Martinelli or a homogeneous formulation, but does correlate nicely with a formulation based on a two-phase Reynolds number. Comparison with ground-based correlations implies that the heat transfer coefficients are lower at reduced gravity than at normal gravity under the same

  17. Local analogs of high-redshift galaxies: Interstellar medium conditions

    NASA Astrophysics Data System (ADS)

    Bian, Fuyan; Kewley, Lisa J.; Dopita, Michael A.; Juneau, Stephanie

    2017-03-01

    Local analog galaxies play an important role in understanding the properties of high-redshift galaxies. We present a method to select a type of local analog that closely resembles the ionized interstellar medium conditions in high-redshift galaxies. These galaxies are selected based on their locations in the [O III]/Hβ versus [N II]/Hα nebular emission-line diagnostic diagram. The ionization parameters and electron densities in these analogs are comparable to those in z ~= 2 - 3 galaxies, but higher than those in normal SDSS galaxies by ~= 0.6 dex and ~= 0.9 dex, respectively. We find that the high sSFR and SFR surface density can enhance the electron densities and the ionization parameters, but still cannot fully explain the difference in ISM condition between nearby galaxies and the local analogs/high-redshift galaxies.

  18. Reduced autonomic activity during stepwise exposure to high altitude.

    PubMed

    Sevre, K; Bendz, B; Hankø, E; Nakstad, A R; Hauge, A; Kåsin, J I; Lefrandt, J D; Smit, A J; Eide, I; Rostrup, M

    2001-12-01

    Several studies have shown increased sympathetic activity during acute exposure to hypobaric hypoxia. In a recent field study we found reduced plasma catecholamines during the first days after a stepwise ascent to high altitude. In the present study 14 subjects were exposed to a simulated ascent in a hypobaric chamber to test the hypothesis of a temporary reduction in autonomic activity. The altitude was increased stepwise to 4500 m over 3 days. Heart rate variability (HRV) was assessed continuously in seven subjects. Baroreceptor reflex sensitivity (BRS) was determined in eight subjects with the 'Transfer Function' method at baseline, at 4500 m and after returning to baseline. Resting plasma catecholamines and cardiovascular- and plasma catecholamine- responses to cold pressor- (CPT) and mental stress-test (MST) were assessed daily in all and 12 subjects, respectively. Data are mean +/- SEM. Compared with baseline at 4500 m there were lower total power (TP) (35 457 +/- 26 302 vs. 15 001 +/- 11 176 ms2), low frequency (LF) power (3112 +/- 809 vs. 1741 +/- 604 ms2), high frequency (HF) power (1466 +/- 520 vs. 459 +/- 189 ms2) and HF normalized units (46 +/- 0.007 vs. 44 +/- 0.006%), P < or = 0.001. Baroreceptor reflex sensitivity decreased (15.6 +/- 2.1 vs. 9.5 +/- 2.6 ms mmHg(-1), P = 0.015). Resting noradrenaline (NA) decreased (522 +/- 98 vs. 357 +/- 60 pmol L(-1), P = 0.027). The increase in systolic blood pressure (SBP) and NA during mental stress was less pronounced (21 +/- 4 vs. 10 +/- 2% and 25 +/- 9 vs. -2 +/- 8%, respectively, P < 0.05). The increase in SBP during cold pressor test decreased (16 +/- 3 vs. 1 +/- 6%, P = 0.03). Diastolic blood pressure, HR and adrenaline displayed similar tendencies. We conclude that a transient reduction in parasympathetic and sympathetic activity was demonstrated during stepwise exposure to high altitude.

  19. Glow discharge techniques for conditioning high vacuum systems

    SciTech Connect

    Dylla, H.F.

    1988-03-01

    A review is given of glow discharge techniques which are useful for conditioning vacuum vessels for high vacuum applications. Substantial development of glow discharge techniques has been done for the purpose of in-situ conditioning of the large ultrahigh vacuum systems for particle accelerators and magnetic fusion devices. In these applications the glow discharge treatments remove impurities from vessel surfaces in order to minimize particle-induced desorption coefficients. Cleaning mechanisms involve a mixture of sputtering and ion- (or neutral) induced desorption effects depending on the gas mixture (ArO/sub 2/ vs. H/sub 2/) and excitation method (DC, RF, and ECR). The author will review the methodology of glow discharge conditioning, diagnostic measurements provided by residual gas and surface composition analysis, and applications to vessel conditioning and materials processing. 76 refs., 16 figs.

  20. Glycerol and urea can be used to increase skin permeability in reduced hydration conditions.

    PubMed

    Björklund, Sebastian; Engblom, Johan; Thuresson, Krister; Sparr, Emma

    2013-12-18

    The natural moisturizing factor (NMF) is a group of hygroscopic molecules that is naturally present in skin and protects from severe drying. Glycerol and urea are two examples of NMF components that are also used in skin care applications. In the present study, we investigate the influence of glycerol and urea on the permeability of a model drug (metronidazole, Mz) across excised pig skin membranes at different hydrating conditions. The degree of skin hydration is regulated by the gradient in water activity across the membrane, which in turn depends on the water activity of the formulation in contact with the skin membrane. Here, we determine the water activity of all formulations employed using an isothermal calorimetric method. Thus, the gradient in water activity is controlled by a novel experimental set-up with well-defined boundary conditions on both sides of the skin membrane. The results demonstrate that glycerol and urea can retain high steady state flux of Mz across skin membranes at dehydrating conditions, which otherwise would decrease the permeability due to dehydration. X-ray diffraction measurements are performed to give insight into the effects of glycerol and urea on SC molecular organization. The novel steady state flux results can be related to the observation that water, glycerol, and urea all affect the structural features of the SC molecular components in a similar manner.

  1. Reduced intensity conditioning allogeneic hematopoietic cell transplantation for adult acute myeloid leukemia in complete remission - a review from the Acute Leukemia Working Party of the EBMT

    PubMed Central

    Sengsayadeth, Salyka; Savani, Bipin N.; Blaise, Didier; Malard, Florent; Nagler, Arnon; Mohty, Mohamad

    2015-01-01

    Acute myeloid leukemia is the most common indication for an allogeneic hematopoietic cell transplant. The introduction of reduced intensity conditioning has expanded the recipient pool for transplantation, which has importantly made transplant an option for the more commonly affected older age groups. Reduced intensity conditioning allogeneic transplantation is currently the standard of care for patients with intermediate or high-risk acute myeloid leukemia and is now most often employed in older patients and those with medical comorbidities. Despite being curative for a significant proportion of patients, post-transplant relapse remains a challenge in the reduced intensity conditioning setting. Herein we discuss the studies that demonstrate the feasibility of reduced intensity conditioning allogeneic transplants, compare the outcomes of reduced intensity conditioning versus chemotherapy and conventional myeloablative conditioning regimens, describe the optimal donor and stem cell source, and consider the impact of post-remission consolidation, comorbidities, center experience, and more intensive (reduced toxicity conditioning) regimens on outcomes. Additionally, we discuss the need for further prospective studies to optimize transplant outcomes. PMID:26130513

  2. SCHOOL AIR CONDITIONING/CASE STUDY, MCPHERSON HIGH SCHOOL.

    ERIC Educational Resources Information Center

    OSTENBERG, JOE W.

    THE STANFORD UNIVERSITY SCHOOL PLANNING LABORATORIES CONDUCTED AN EDUCATIONAL SURVEY OF THE EDUCATIONAL NEEDS OF THE MCPHERSON CITY SCHOOLS BY STUDYING THE EXISTING CONDITIONS, LOCAL ECONOMIES, AND POTENTIAL POPULATION GROWTH. IT WAS RECOMMENDED THAT A NEW SENIOR HIGH BE BUILT TO HOUSE 700-750 STUDENTS, THE ANTICIPATED ENROLLMENT 10 YEARS AFTER…

  3. Mechanical Isolation of Highly Stable Antimonene under Ambient Conditions.

    PubMed

    Ares, Pablo; Aguilar-Galindo, Fernando; Rodríguez-San-Miguel, David; Aldave, Diego A; Díaz-Tendero, Sergio; Alcamí, Manuel; Martín, Fernando; Gómez-Herrero, Julio; Zamora, Félix

    2016-08-01

    Antimonene fabricated by mechanical exfoliation is highly stable under atmospheric conditions over periods of months and even when immersed in water. Density functional theory confirms the experiments and predicts an electronic gap of ≈1 eV. These results highlight the use of antimonene for optoelectronics applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. SCHOOL AIR CONDITIONING/CASE STUDY, MCPHERSON HIGH SCHOOL.

    ERIC Educational Resources Information Center

    OSTENBERG, JOE W.

    THE STANFORD UNIVERSITY SCHOOL PLANNING LABORATORIES CONDUCTED AN EDUCATIONAL SURVEY OF THE EDUCATIONAL NEEDS OF THE MCPHERSON CITY SCHOOLS BY STUDYING THE EXISTING CONDITIONS, LOCAL ECONOMIES, AND POTENTIAL POPULATION GROWTH. IT WAS RECOMMENDED THAT A NEW SENIOR HIGH BE BUILT TO HOUSE 700-750 STUDENTS, THE ANTICIPATED ENROLLMENT 10 YEARS AFTER…

  5. Changes in Soil Minerology Reduce Phosphorus Mobility During Anoxic Soil Conditions

    NASA Astrophysics Data System (ADS)

    Giri, S. K.; Geohring, L. D.; Richards, B. K.; Walter, M.; Steenhuis, T. S.

    2008-05-01

    soil incubation showed higher P sorption than aerobic soil due to reduced iron (Fe+2) - P mineral formation. Some of the readily available P in the soil solution tended to co-precipitate quickly with Fe, Al, Ca, and Mn, but it also resulted in the formation of earthy masses of vivianite [Fe2+3(PO4)2 . 8 H20], thus almost completely immobilizing P. These findings suggest that where conditions in the landscape are saturated, but remain stagnant for extended time periods, P additions may not necessarily enhance leaching once hydrological transport resumes. The temporal nature of P mobilization processes combined with rapid (i.e., preferential flow) hydrological transport appears to have a more important role in controlling P transport through the landscape.

  6. Ignition and combustion of bulk metals under elevated, normal and reduced gravity conditions

    NASA Technical Reports Server (NTRS)

    Abbud-Madrid, Angel; Branch, Melvyn C.; Daily, John W.

    1995-01-01

    This research effort is aimed at providing further insight into this multi-variable dependent phenomena by looking at the effects of gravity on the ignition and combustion behavior of metals. Since spacecraft are subjected to higher-than-1g gravity loads during launch and reentry and to zero-gravity environments while in orbit, the study of ignition and combustion of bulk metals at different gravitational potentials is of great practical concern. From the scientific standpoint, studies conducted under microgravity conditions provide simplified boundary conditions since buoyancy is removed, and make possible the identification of fundamental ignition mechanisms. The effect of microgravity on the combustion of bulk metals has been investigated by Steinberg, et al. on a drop tower simulator. However, no detailed quantitative work has been done on ignition phenomena of bulk metals at lower or higher-than-normal gravitational fields or on the combustion characteristics of metals at elevated gravity. The primary objective of this investigation is the development of an experimental system capable of providing fundamental physical and chemical information on the ignition of bulk metals under different gravity levels. The metals used in the study, iron (Fe), titanium (Ti), zirconium (Zr), magnesium (Mg), zinc (Zn), and copper (Cu) were selected because of their importance as elements of structural metals and their simple chemical composition (pure metals instead of multi-component alloys to avoid complication in morphology and spectroscopic studies). These samples were also chosen to study the two different combustion modes experienced by metals: heterogeneous or surface oxidation, and homogeneous or gas-phase reaction. The experimental approach provides surface temperature profiles, spectroscopic measurements, surface morphology, x-ray spectrometry of metals specimens and their combustion products, and high-speed cinematography of the heating, ignition and combustion

  7. An Intermediate Alemtuzumab Schedule Reduces the Incidence of Mixed Chimerism Following Reduced-Intensity Conditioning Hematopoietic Cell Transplantation for Hemophagocytic Lymphohistiocytosis

    PubMed Central

    Marsh, Rebecca A.; Kim, Mi-Ok; Liu, Chunyan; Bellman, Denise; Hart, Laura; Grimley, Michael; Kumar, Ashish; Jodele, Sonata; Myers, Kasiani C.; Chandra, Sharat; Leemhuis, Tom; Mehta, Parinda A.; Bleesing, Jack J.; Davies, Stella M.; Jordan, Michael B.; Filipovich, Alexandra H.

    2014-01-01

    Reduced-intensity conditioning (RIC) improves the outcomes of hematopoietic cell transplantation (HCT) in patients with hemophagocytic lymphohistiocytosis (HLH). Proximal (ie, close to graft infusion) dosing of alemtuzumab is associated with a high incidence of mixed chimerism, whereas distal (ie, distant from graft infusion) dosing is associated with less mixed chimerism but more acute graft-versus-host disease (GVHD). The alemtuzumab dose per kilogram of body weight also influences these outcomes. We hypothesized that an intermediate alemtuzumab dosing schedule would reduce mixed chimerism and maintain a low incidence of acute GVHD. In this study, 24 consecutive HCTs were performed in patients with HLH or a related disorder using a novel intermediate alemtuzumab schedule of 1 mg/kg starting on day -14. The cumulative incidences (CIs) of mixed chimerism, upfront acute GVHD grades II-IV, and receipt of additional hematopoietic cell products after HCT were compared in patients treated with a distal alemtuzumab schedule (n = 15) and those treated with a proximal alemtuzumab schedule (n = 33). All patients received fludarabine and melphalan. The CI of mixed chimerism was 31% in the intermediate group, 72% in the proximal group (P < .01), and 75% in the distal group patients who received ≥2 mg/kg alemtuzumab (P = .03). The CI of acute GVHD grades II-IV before the development of mixed chimerism was 4% in the intermediate group, 0% in the proximal group, and 13% in the distal group (P = .04, proximal versus distal). The 1-year CI of administration of additional hematopoietic cell products for mixed chimerism (donor lymphocyte infusion ± hematopoietic stem cell boost ± repeat HCT) was 14% in the intermediate group, 53% in the proximal group (P = .01), and 38% in the distal ≥2 mg/kg alemtuzumab group (P = .02). Our findings indicate that intermediate RIC reduces the incidence of mixed chimerism, is associated with a low incidence of upfront acute GVHD, and decreases

  8. Reduced nonlinearities in 100-nm high SOI waveguides

    NASA Astrophysics Data System (ADS)

    Lacava, C.; Marchetti, R.; Vitali, V.; Cristiani, I.; Giuliani, G.; Fournier, M.; Bernabe, S.; Minzioni, P.

    2016-03-01

    Here we show the results of an experimental analysis dedicated to investigate the impact of optical non linear effects, such as two-photon absorption (TPA), free-carrier absorption (FCA) and free-carrier dispersion (FCD), on the performance of integrated micro-resonator based filters for application in WDM telecommunication systems. The filters were fabricated using SOI (Silicon-on-Insulator) technology by CEA-Leti, in the frame of the FP7 Fabulous Project, which aims to develop low-cost and high-performance integrated optical devices to be used in new generation passive optical- networks (NG-PON2). Different designs were tested, including both ring-based structures and racetrack-based structures, with single-, double- or triple- resonator configuration, and using different waveguide cross-sections (from 500 x 200 nm to 825 x 100 nm). Measurements were carried out using an external cavity tunable laser source operating in the extended telecom bandwidth, using both continuous wave signals and 10 Gbit/s modulated signals. Results show that the use 100-nm high waveguide allows reducing the impact of non-linear losses, with respect to the standard waveguides, thus increasing by more than 3 dB the maximum amount of optical power that can be injected into the devices before causing significant non-linear effects. Measurements with OOK-modulated signals at 10 Gbit/s showed that TPA and FCA don't affect the back-to-back BER of the signal, even when long pseudo-random-bit-sequences (PRBS) are used, as the FCD-induced filter-detuning increases filter losses but "prevents" excessive signal degradation.

  9. Proteomic analysis of Saccharomyces cerevisiae under high gravity fermentation conditions.

    PubMed

    Pham, Trong Khoa; Chong, Poh Kuan; Gan, Chee Sian; Wright, Phillip C

    2006-12-01

    Saccharomyces cerevisiae KAY446 was utilized for ethanol production, with glucose concentrations ranging from 120 g/L (normal) to 300 g/L (high). Although grown in a high glucose environment, S. cerevisiae still retained the ability to produce ethanol with a high degree of glucose utilization. iTRAQ-mediated shotgun proteomics was applied to identify relative expression change of proteins under the different glucose conditions. A total of 413 proteins were identified from three replicate, independent LC-MS/MS runs. Unsurprisingly, many proteins in the glycolysis/gluconeogenesis pathway showed significant changes in expression level. Twenty five proteins involved in amino acid metabolism decreased their expression, while the expressions of 12 heat-shock related proteins were also identified. Under high glucose conditions, ethanol was produced as a major product. However, the assimilation of glucose as well as a number of byproducts was also enhanced. Therefore, to optimize the ethanol production under very high gravity conditions, a number of pathways will need to be deactivated, while still maintaining the correct cellular redox or osmotic state. Proteomics is demonstrated here as a tool to aid in this forward metabolic engineering.

  10. High Temperature Decomposition of Almandine and Pyrope in Reducing Atmosphere

    NASA Astrophysics Data System (ADS)

    Aparicio, C.; Filip, J.; Mashlan, M.

    2010-07-01

    Thermal decomposition of two garnets of near end-member composition—almandine (Fe2.85Mg0.15)(Al1.99)Si2.99O12 and pyrope (Mg2.22Fe0.47Ca0.33)(Cr0.11Fe0.06Al1.81)Si2.98O12—has been carried out in reducing atmosphere (forming gas: 10% of H2 in N2). High-temperature behavior of both samples was monitored using simultaneous thermogravimetry and differential scanning calorimetry. The decomposition of almandine and pyrope turned out to proceed at slightly different temperatures above 1000 °C. Therefore, two series of samples were prepared based on the results of thermal analysis: almandine heated up to 950 °C, 1070 °C and 1200 °C, and pyrope heated up to 1000 °C, 1100 °C, 1125 °C and 1200 °C. The identification of the decomposition products was performed by X-ray powder diffraction and Mössbauer spectroscopy. The common feature of the decomposition of both garnets is the presence of metallic iron and spinel phase, while the other products include fayalite, cristobalite, and cordierite for almandine; and enstatite and anorthite for pyrope. The formation of this last component was enabled due to Ca content in pyrope.

  11. Reducing peanut allergens by high pressure combined with polyphenol oxidase

    NASA Astrophysics Data System (ADS)

    Chung, Si-Yin; Houska, Milan; Reed, Shawndrika

    2013-12-01

    Polyphenol oxidase (PPO) has been shown to reduce major peanut allergens. Since high pressure (HP) can increase enzyme activity, we postulated that further reduction of peanut allergens can be achieved through HP combined with PPO. Peanut extracts containing caffeic acid were treated with each of the following: (1) HP; (2) HP+PPO; (3) PPO; and (4) none. HP was conducted at 300 and 500 MPa, each for 3 and 10 min, 37 °C. After treatment, SDS-PAGE was performed and allergenic capacity (IgE binding) was determined colorimetrically in inhibition enzyme-linked immunosorbent assay and Western blots, using a pooled plasma from peanut-allergic patients. Data showed that HP alone had no effect on major peanut allergens. However, HP at 500 MPa combined with PPO (HP500/PPO) induced a higher (approximately twofold) reduction of major peanut allergens and IgE binding than PPO alone or HP300/PPO. There was no difference between treatment times. We concluded that HP500/PPO at 3-min enhanced a twofold reduction of the allergenic capacity of peanut extracts, as compared to PPO itself.

  12. High Temperature Decomposition of Almandine and Pyrope in Reducing Atmosphere

    SciTech Connect

    Aparicio, C.; Filip, J.; Mashlan, M.

    2010-07-13

    Thermal decomposition of two garnets of near end-member composition--almandine (Fe{sub 2.85}Mg{sub 0.15})(Al{sub 1.99})Si{sub 2.99}O{sub 12} and pyrope (Mg{sub 2.22}Fe{sub 0.47}Ca{sub 0.33})(Cr{sub 0.11}Fe{sub 0.06}Al{sub 1.81})Si{sub 2.98}O{sub 12}--has been carried out in reducing atmosphere (forming gas: 10% of H{sub 2} in N{sub 2}). High-temperature behavior of both samples was monitored using simultaneous thermogravimetry and differential scanning calorimetry. The decomposition of almandine and pyrope turned out to proceed at slightly different temperatures above 1000 degree sign C. Therefore, two series of samples were prepared based on the results of thermal analysis: almandine heated up to 950 deg. C, 1070 deg. C and 1200 deg. C, and pyrope heated up to 1000 deg. C, 1100 deg. C, 1125 deg. C and 1200 deg. C. The identification of the decomposition products was performed by X-ray powder diffraction and Moessbauer spectroscopy. The common feature of the decomposition of both garnets is the presence of metallic iron and spinel phase, while the other products include fayalite, cristobalite, and cordierite for almandine; and enstatite and anorthite for pyrope. The formation of this last component was enabled due to Ca content in pyrope.

  13. Does "transition shoe" promote an intermediate biomechanical condition compared to running in conventional shoe and in reduced protection condition?

    PubMed

    da Silva Azevedo, Ana Paula; Mezêncio, Bruno; Valvassori, Raísa; Mochizuki, Luis; Amadio, Alberto Carlos; Serrão, Júlio Cerca

    2016-05-01

    This study evaluated if running in a "transition shoe" commercially available results in intermediate mechanical load upon lower extremities compared to conventional shoe and minimalist shoe/barefoot. Kinematic and kinetic parameters while running in different shoe conditions were compared. Fourteen runners (12 men, 2 women; age=28.4±7.3 years), inexperienced in minimalist shoes and barefoot running, ran on an instrumented treadmill within four experimental conditions (conventional shoe - CS, transition shoe - TrS, minimalist shoe - MS, and barefoot - BF). Running was performed at 9km/h for 10min in each experimental condition. Vertical ground reaction force (VGRF) and two-dimensional kinematic variables of lower limbs (both legs) were recorded. Nine data acquisitions (10s) were conducted for each footwear condition. Transition shoe lead to significant changes in VGRF variables related to impact control, while kinematic parameters were little affected. The TrS had smaller first peak of VGRF (Fy1) than CS (p≤0.001) and higher than MS (p=0.050) and BF (p≤0.001). Time to first peak of VGRF (tFy1) of TrS was smaller than CS (p≤0.001) and higher than MS (p≤0.001) and BF (p≤0.001). The TrS and MS induced to lesser knee flexion (p<0.001) and greater dorsiflexion (p<0.001) than CS and BF. Thus, results suggest the transition shoe (TrS) tested seem to promote an intermediate mechanical load condition only for VGRF parameters, presenting values of impact forces between those found for conventional shoe and minimalist shoe/barefoot. Such knowledge could be useful for the transition process from conventional running shoe to minimalist shoe/barefoot.

  14. Microbial Anaerobic Ammonium Oxidation Under Iron Reducing Conditions, Alternative Electron Acceptors

    NASA Astrophysics Data System (ADS)

    Ruiz-Urigüen, M.; Jaffe, P. R.

    2015-12-01

    Autotrophic Acidimicrobiaceae-bacterium named A6 (A6), part of the Actinobacteria phylum have been linked to anaerobic ammonium (NH4+) oxidation under iron reducing conditions. These organisms obtain their energy by oxidizing NH4+ and transferring the electrons to a terminal electron acceptor (TEA). Under environmental conditions, the TEAs are iron oxides [Fe(III)], which are reduced to Fe(II), this process is known as Feammox. Our studies indicate that alternative forms of TEAs can be used by A6, e.g. iron rich clays (i.e. nontronite) and electrodes in bioelectrochemical systems such as Microbial Electrolysis Cells (MECs), which can sustain NH4+removal and A6 biomass production. Our results show that nontronite can support Feammox and promote bacterial cell production. A6 biomass increased from 4.7 x 104 to 3.9 x 105 cells/ml in 10 days. Incubations of A6 in nontronite resulted in up to 10 times more NH4+ removal and 3 times more biomass production than when ferrihydrite is used as the Fe(III) source. Additionally, Fe in nontronite can be reoxidized by aeration and A6 can reutilize it; however, Fe is still finite in the clay. In contrast, in MECs, A6 harvest electrons from NH4+ and use an anode as an unlimited TEA, as a result current is produced. We operated multiple MECs in parallel using a single external power source, as described by Call & Logan (2011). MECs were run with an applied voltage of 0.7V and different growing mediums always containing initial 5mM NH4+. Results show that current production is favored when anthraquinone-2,6-disulfonate (AQDS), an electron shuttled, is present in the medium as it facilitates the transfer of electrons from the bacterial cell to the anode. Additionally, A6 biomass increased from 1 x 104 to 9.77 x 105cells/ml in 14 days of operation. Due to Acidimicrobiaceae-bacterium A6's ability to use various TEAs, MECs represent an alternative, iron-free form, for optimized biomass production of A6 and its application in NH4

  15. A Conditional Cash Transfer Program in the Philippines Reduces Severe Stunting.

    PubMed

    Kandpal, Eeshani; Alderman, Harold; Friedman, Jed; Filmer, Deon; Onishi, Junko; Avalos, Jorge

    2016-09-01

    Pantawid, a conditional cash transfer (CCT) program in the Philippines, provided grants conditioned on health-related behaviors for children aged 0-5 y and schooling for those aged 10-14 y. We investigated whether Pantawid improved anthropometric measurements in children aged 6-36 mo. We estimated cross-sectional intention-to-treat effects using a 2011 cluster-randomized trial across 130 villages-65 treated and 65 control-with data collected after 31 mo of implementation. Anthropometry characteristics were measured for 241 children in treated areas and 244 children in control areas. Health service use for children aged 6-36 mo and dietary intake for those aged 6-60 mo also were measured. Outcome variables were height-for-age z scores (HAZs) and weight-for-age z scores (WAZs), stunting, severe stunting, underweight, and severely underweight. Impact also was assessed on perinatal care, institutional delivery, presence of skilled birth attendant, breastfeeding practices, immunization, growth monitoring and deworming, care-seeking, and children's intake of protein-rich foods. Pantawid was associated with a significant reduction in severe stunting [<-3 SD from WHO standards for healthy children; β = -10.2 percentage points (95% CI -18.8, -1.6 percentage points); P = 0.020] as well as a marginally significant increase in HAZs [β = 0.284 SDs (95% CI -0.033, 0.602 SDs); P = 0.08]. WAZs, stunting, underweight, and severely underweight status did not change. Concomitantly, several measures of health-seeking behavior increased significantly. To our knowledge, Pantawid is one of few CCT programs worldwide that significantly reduced severe stunting in children aged 6-36 mo; changes in key parenting practices, including children's intake of protein-rich foods and care-seeking behavior, were concurrent. © 2016 American Society for Nutrition.

  16. High Energy Boundary Conditions for a Cartesian Mesh Euler Solver

    NASA Technical Reports Server (NTRS)

    Pandya, Shishir A.; Murman, Scott M.; Aftosmis, Michael J.

    2004-01-01

    Inlets and exhaust nozzles are often omitted or fared over in aerodynamic simulations of aircraft due to the complexities involving in the modeling of engine details such as complex geometry and flow physics. However, the assumption is often improper as inlet or plume flows have a substantial effect on vehicle aerodynamics. A tool for specifying inlet and exhaust plume conditions through the use of high-energy boundary conditions in an established inviscid flow solver is presented. The effects of the plume on the flow fields near the inlet and plume are discussed.

  17. Reduced nonlinear prognostic model construction from high-dimensional data

    NASA Astrophysics Data System (ADS)

    Gavrilov, Andrey; Mukhin, Dmitry; Loskutov, Evgeny; Feigin, Alexander

    2017-04-01

    Construction of a data-driven model of evolution operator using universal approximating functions can only be statistically justified when the dimension of its phase space is small enough, especially in the case of short time series. At the same time in many applications real-measured data is high-dimensional, e.g. it is space-distributed and multivariate in climate science. Therefore it is necessary to use efficient dimensionality reduction methods which are also able to capture key dynamical properties of the system from observed data. To address this problem we present a Bayesian approach to an evolution operator construction which incorporates two key reduction steps. First, the data is decomposed into a set of certain empirical modes, such as standard empirical orthogonal functions or recently suggested nonlinear dynamical modes (NDMs) [1], and the reduced space of corresponding principal components (PCs) is obtained. Then, the model of evolution operator for PCs is constructed which maps a number of states in the past to the current state. The second step is to reduce this time-extended space in the past using appropriate decomposition methods. Such a reduction allows us to capture only the most significant spatio-temporal couplings. The functional form of the evolution operator includes separately linear, nonlinear (based on artificial neural networks) and stochastic terms. Explicit separation of the linear term from the nonlinear one allows us to more easily interpret degree of nonlinearity as well as to deal better with smooth PCs which can naturally occur in the decompositions like NDM, as they provide a time scale separation. Results of application of the proposed method to climate data are demonstrated and discussed. The study is supported by Government of Russian Federation (agreement #14.Z50.31.0033 with the Institute of Applied Physics of RAS). 1. Mukhin, D., Gavrilov, A., Feigin, A., Loskutov, E., & Kurths, J. (2015). Principal nonlinear dynamical

  18. Soluble electron shuttles control microbial community development under iron-reducing conditions in wetland sediment microcosms

    NASA Astrophysics Data System (ADS)

    Flynn, T. M.; Sladek, M. F.; Jensvold, Z. D.; Antonopoulos, D. A.; Koval, J. C.; Kemner, K. M.; O'Loughlin, E. J.

    2016-12-01

    Dissimilatory metal-reducing bacteria (DMRB) inhabit sedimentary environments throughout the critical zone, gaining energy by coupling the oxidation of reduced organic compounds or H2 to the reduction of iron and other metal oxides. These oxides are poorly soluble at the temperature and pH ranges typical of most critical zone environments, and consequently many DMRB use soluble electron-shuttling compounds to aid the transfer of electrons to these extracellular electron acceptors. Pure culture studies suggest these electron shuttles enhance the overall rate of iron reduction, yet little is known about how the presence of these compounds affects complex native communities of microorganisms under iron-reducing conditions. We examined the effect quinone-based electron shuttles with different redox potentials have on the rate of iron reduction, the onset of methanogenesis, and the trajectory of microbial community development in wetland sediment microcosms amended with goethite (α-FeOOH) and either acetate or H2. Unlike pure culture experiments, microcosms given 9,10-anthraquinone-2-carboxylic acid (AQC) or 5-hydroxy-1,4-naphthoquinone (lawsone, NQL) showed no increase in the rate of iron reduction relative to control experiments with no shuttle (NS) added. The rate and extent of iron reduction increased significantly however in those given 9,10-anthraquinone-2,6-disulfonate (AQDS). Methanogenesis did not begin in AQDS, NQL, or NS microcosms until ferrous iron production ceased and was inhibited entirely in AQC-amended microcosms. These AQC-amended microcosms also showed a significant divergence from the others in microbial community development. 16S rRNA sequences classified as Geobacteraceae dominated NS control microcosms (61% average abundance) as well as those amended with AQDS (42-65%) and NQL (62%), though distinct operational taxonomic units (OTUs) were abundant depending on the shuttle used. AQC microcosms were instead dominated by Pelobacteraceae (68% in

  19. Long-term microplastic retention causes reduced body condition in the langoustine, Nephrops norvegicus.

    PubMed

    Welden, Natalie A C; Cowie, Phillip R

    2016-11-01

    Microplastic represents a rising proportion of marine litter and is widely distributed throughout a range of marine habitats. Correspondingly, the number of reports of species containing microplastics increases annually. Nephrops norvegicus in the Firth of Clyde have previously been shown to retain large aggregations of microplastic fibres. The potential for N. norvegicus to retain plastic over an extended time period increases the likelihood of any associated negative impacts to the individual. This study represents the longest observation of the impacts of microplastic retention in invertebrates. We exposed N. norvegicus to plastic over eight months to determine the impacts of extended exposure. Over this period we compared the feeding rate, body mass, and nutritional state of plastic-fed N. norvegicus to that of fed and starved control groups. Following the experimental period, the plastic-fed langoustine contained microplastic aggregations comparable to those of small individuals from the Clyde Sea Area. Comparisons between fed, unfed and plastic-fed individuals indicated a reduction in feeding rate, body mass, and metabolic rate as well as catabolism of stored lipids in plastic contaminated animals. We conclude that N. norvegicus exposed to high levels of environmental microplastic pollution may experience reduced nutrient availability. This can result in reduced population stability and may affect the viability of local fisheries. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Electric Current Activated Combustion Synthesis and Chemical Ovens Under Terrestrial and Reduced Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Unuvar, C.; Fredrick, D.; Anselmi-Tamburini, U.; Manerbino, A.; Guigne, J. Y.; Munir, Z. A.; Shaw, B. D.

    2004-01-01

    Combustion synthesis (CS) generally involves mixing reactants together (e.g., metal powders) and igniting the mixture. Typically, a reaction wave will pass through the sample. In field activated combustion synthesis (FACS), the addition of an electric field has a marked effect on the dynamics of wave propagation and on the nature, composition, and homogeneity of the product as well as capillary flow, mass-transport in porous media, and Marangoni flows, which are influenced by gravity. The objective is to understand the role of an electric field in CS reactions under conditions where gravity-related effects are suppressed or altered. The systems being studied are Ti+Al and Ti+3Al. Two different ignition orientations have been used to observe effects of gravity when one of the reactants becomes molten. This consequentially influences the position and concentration of the electric current, which in turn influences the entire process. Experiments have also been performed in microgravity conditions. This process has been named Microgravity Field Activated Combustion Synthesis (MFACS). Effects of gravity have been demonstrated, where the reaction wave temperature and velocity demonstrate considerable differences besides the changes of combustion mechanisms with the different high currents applied. Also the threshold for the formation of a stable reaction wave is increased under zero gravity conditions. Electric current was also utilized with a chemical oven technique, where inserts of aluminum with minute amounts of tungsten and tantalum were used to allow observation of effects of settling of the higher density solid particles in liquid aluminum at the present temperature profile and wave velocity of the reaction.

  1. Impact of ABO blood group mismatch in alemtuzumab-based reduced-intensity conditioned haematopoietic SCT.

    PubMed

    Brierley, C K; Littlewood, T J; Peniket, A J; Gregg, R; Ward, J; Clark, A; Parker, A; Malladi, R; Medd, P

    2015-07-01

    The impact of ABO incompatibility on clinical outcomes following haematopoietic SCT (HSCT) remains controversial. This retrospective study assessed the effect of ABO mismatch on transplant outcomes and transfusion requirements in 594 patients undergoing reduced-intensity conditioned (RIC) HSCT with alemtuzumab in three UK transplant centres. We found no significant effects of minor, major or bidirectional ABO mismatch on overall survival, relapse-free survival, nonrelapse mortality or relapse incidence. Although the rate of acute GVHD was unaffected by ABO mismatch, the incidence of extensive chronic GVHD was higher in patients with minor and major mismatch compared with those who were ABO matched (hazard ratio (HR) 1.74, P=0.032 for minor, HR 1.69 P=0.0036 for major mismatch). Red cell and platelet transfusion requirements in the first 100 days post transplant did not differ by ABO mismatch. In this large UK series, ABO mismatch in RIC HSCT has no clinically significant effect on survival outcomes but appears to modify susceptibility to extensive chronic GVHD.

  2. Biofuel blending reduces particle emissions from aircraft engines at cruise conditions

    NASA Astrophysics Data System (ADS)

    Moore, Richard H.; Thornhill, Kenneth L.; Weinzierl, Bernadett; Sauer, Daniel; D'Ascoli, Eugenio; Kim, Jin; Lichtenstern, Michael; Scheibe, Monika; Beaton, Brian; Beyersdorf, Andreas J.; Barrick, John; Bulzan, Dan; Corr, Chelsea A.; Crosbie, Ewan; Jurkat, Tina; Martin, Robert; Riddick, Dean; Shook, Michael; Slover, Gregory; Voigt, Christiane; White, Robert; Winstead, Edward; Yasky, Richard; Ziemba, Luke D.; Brown, Anthony; Schlager, Hans; Anderson, Bruce E.

    2017-03-01

    Aviation-related aerosol emissions contribute to the formation of contrail cirrus clouds that can alter upper tropospheric radiation and water budgets, and therefore climate. The magnitude of air-traffic-related aerosol-cloud interactions and the ways in which these interactions might change in the future remain uncertain. Modelling studies of the present and future effects of aviation on climate require detailed information about the number of aerosol particles emitted per kilogram of fuel burned and the microphysical properties of those aerosols that are relevant for cloud formation. However, previous observational data at cruise altitudes are sparse for engines burning conventional fuels, and no data have previously been reported for biofuel use in-flight. Here we report observations from research aircraft that sampled the exhaust of engines onboard a NASA DC-8 aircraft as they burned conventional Jet A fuel and a 50:50 (by volume) blend of Jet A fuel and a biofuel derived from Camelina oil. We show that, compared to using conventional fuels, biofuel blending reduces particle number and mass emissions immediately behind the aircraft by 50 to 70 per cent. Our observations quantify the impact of biofuel blending on aerosol emissions at cruise conditions and provide key microphysical parameters, which will be useful to assess the potential of biofuel use in aviation as a viable strategy to mitigate climate change.

  3. Achieving stringent CR is essential before reduced-intensity conditioning allogeneic hematopoietic cell transplantation in AML.

    PubMed

    Ustun, C; Wiseman, A C; Defor, T E; Yohe, S; Linden, M A; Oran, B; Burke, M; Warlick, E; Miller, J S; Weisdorf, D

    2013-11-01

    Reduced-intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (allo-HCT) can cure patients with AML in CR. However, relapse after RIC allo-HCT may indicate heterogeneity in the stringency of CR. Strict definition of CR requires no evidence of leukemia by both morphologic and flow cytometric criteria. We re-evaluated 85 AML patients receiving RIC allo-HCT in CR to test if a strict definition of CR had direct implications for the outcome. These patients had leukemia immunophenotype documented at diagnosis and analyzed at allo-HCT. Eight (9.4%) had persistent leukemia by flow cytometric criteria at allo-HCT. The patients with immunophenotypic persistent leukemia had a significantly increased relapse (hazard ratio (HR): 3.7; 95% confidence interval (CI): 1.3-10.3, P=0.01) and decreased survival (HR: 2.9; 95% CI: 1.3-6.4, P<0.01) versus 77 patients in CR by both morphology and flow cytometry. However, the pre-allo-HCT bone marrow (BM) blast count (that is, 0-4%) was not significantly associated with risks of relapse or survival. These data indicate the presence of leukemic cells, but not the BM blast count affects survival. A strict morphologic and clinical lab flow cytometric definition of CR predicts outcomes after RIC allo-HCT, and therefore is critical to achieve at transplantation.

  4. Sonification of in-vehicle interface reduces gaze movements under dual-task condition.

    PubMed

    Tardieu, Julien; Misdariis, Nicolas; Langlois, Sabine; Gaillard, Pascal; Lemercier, Céline

    2015-09-01

    In-car infotainment systems (ICIS) often degrade driving performances since they divert the driver's gaze from the driving scene. Sonification of hierarchical menus (such as those found in most ICIS) is examined in this paper as one possible solution to reduce gaze movements towards the visual display. In a dual-task experiment in the laboratory, 46 participants were requested to prioritize a primary task (a continuous target detection task) and to simultaneously navigate in a realistic mock-up of an ICIS, either sonified or not. Results indicated that sonification significantly increased the time spent looking at the primary task, and significantly decreased the number and the duration of gaze saccades towards the ICIS. In other words, the sonified ICIS could be used nearly exclusively by ear. On the other hand, the reaction times in the primary task were increased in both silent and sonified conditions. This study suggests that sonification of secondary tasks while driving could improve the driver's visual attention of the driving scene.

  5. Biofuel blending reduces particle emissions from aircraft engines at cruise conditions.

    PubMed

    Moore, Richard H; Thornhill, Kenneth L; Weinzierl, Bernadett; Sauer, Daniel; D'Ascoli, Eugenio; Kim, Jin; Lichtenstern, Michael; Scheibe, Monika; Beaton, Brian; Beyersdorf, Andreas J; Barrick, John; Bulzan, Dan; Corr, Chelsea A; Crosbie, Ewan; Jurkat, Tina; Martin, Robert; Riddick, Dean; Shook, Michael; Slover, Gregory; Voigt, Christiane; White, Robert; Winstead, Edward; Yasky, Richard; Ziemba, Luke D; Brown, Anthony; Schlager, Hans; Anderson, Bruce E

    2017-03-15

    Aviation-related aerosol emissions contribute to the formation of contrail cirrus clouds that can alter upper tropospheric radiation and water budgets, and therefore climate. The magnitude of air-traffic-related aerosol-cloud interactions and the ways in which these interactions might change in the future remain uncertain. Modelling studies of the present and future effects of aviation on climate require detailed information about the number of aerosol particles emitted per kilogram of fuel burned and the microphysical properties of those aerosols that are relevant for cloud formation. However, previous observational data at cruise altitudes are sparse for engines burning conventional fuels, and no data have previously been reported for biofuel use in-flight. Here we report observations from research aircraft that sampled the exhaust of engines onboard a NASA DC-8 aircraft as they burned conventional Jet A fuel and a 50:50 (by volume) blend of Jet A fuel and a biofuel derived from Camelina oil. We show that, compared to using conventional fuels, biofuel blending reduces particle number and mass emissions immediately behind the aircraft by 50 to 70 per cent. Our observations quantify the impact of biofuel blending on aerosol emissions at cruise conditions and provide key microphysical parameters, which will be useful to assess the potential of biofuel use in aviation as a viable strategy to mitigate climate change.

  6. The interactive biotic and abiotic processes of DDT transformation under dissimilatory iron-reducing conditions.

    PubMed

    Jin, Xin; Wang, Fang; Gu, Chenggang; Yang, Xinglun; Kengara, Fredrick O; Bian, Yongrong; Song, Yang; Jiang, Xin

    2015-11-01

    The objective of the study was to elucidate the biotic and abiotic processes under dissimilatory iron reducing conditions involved in reductive dechlorination and iron reduction. DDT transformation was investigated in cultures of Shewanella putrefaciens 200 with/without α-FeOOH. A modified first-order kinetics model was developed and described DDT transformation well. Both the α-FeOOH reduction rate and the dechlorination rate of DDT were positively correlated to the biomass. Addition of α-FeOOH enhanced reductive dechlorination of DDT by favoring the cell survival and generating Fe(II) which was absorbed on the surface of bacteria and iron oxide. 92% of the absorbed Fe(II) was Na-acetate (1M) extractable. However, α-FeOOH also played a negative role of competing for electrons as reflected by the dechlorination rate of DDT was inhibited when increasing the α-FeOOH from 1 g L(-1) to 5 g L(-1). DDT was measured to be toxic to S. putrefaciens 200. The metabolites DDD, DDE and DDMU were recalcitrant to S. putrefaciens 200. The results suggested that iron oxide was not the key factor to promote the dissipation of DDX (DDT and the metabolites), whereas the one-electron reduction potential (E1) of certain organochlorines is the main factor and that the E1 higher than the threshold of the reductive driving forces of DIRB probably ensures the occur of reductive dechlorination.

  7. Fracture process of nonstoichiometric oxide based solid oxide fuel cell under oxidizing/reducing gradient conditions

    NASA Astrophysics Data System (ADS)

    Sato, Kazuhisa; Yashiro, Keiji; Kawada, Tatsuya; Yugami, Hiroo; Hashida, Toshiyuki; Mizusaki, Junichiro

    The influence of chemically induced expansion on the fracture damage of a nonstoichiometric oxide (ceria) based solid oxide fuel cell (SOFC) single cell laminate was investigated by using numerical stress analyses under oxidizing/reducing gradient condition. The single cell examined in this study was composed of electrolyte (Ce 0.8Sm 0.2O 2- δ), anode (Cermets of Ni-Ce 0.8Sm 0.2O 2- δ), and cathode (La 0.6Sr 0.4Co 0.2Fe 0.8O 3- δ), respectively. The finite element method (FEM) was employed to calculate the residual stress, thermal stresses, and chemically induced expansion stresses for the single cell. The residual and thermal stresses were calculated much smaller than the fracture strength of the individual components of the single cell. On the other hand, the chemically induced expansion stresses were shown to remarkably increase for the temperature range greater than 973 K and accounted their magnitude for primary part of the induced stress. It was shown from the FEM that the maximum circumferential stress induced in the single cell exceeded the fracture strength of the individual components at the onset of the fracture damage detect by acoustic emission (AE) method.

  8. Fibroblast growth factor-2 enhances extinction and reduces renewal of conditioned fear.

    PubMed

    Graham, Bronwyn M; Richardson, Rick

    2010-05-01

    Anxiety disorders are increasingly prevalent in society; hence, there is a need to improve on existing treatments for such disorders. Fibroblast growth factor-2 (FGF2), a mitogen that is involved in brain development and regeneration, has been shown to both facilitate long-term extinction of fear and reduce stress-precipitated relapse in rats. Extinction is the laboratory analog of exposure-based therapies in humans. In this study, we continued to investigate the clinical potential of FGF2 as a pharmacological enhancer of extinction by examining its effect on renewal, a common type of relapse. In all experiments, rats were trained to fear a white noise-conditioned stimulus, and then this learned fear was extinguished the following day. Rats received systemic injections of FGF2 or vehicle immediately after extinction training. At test, on the day after extinction training, levels of freezing elicited by the white noise in either the extinction context or the original training context were measured. FGF2-treated rats showed less renewal of fear when tested in the original training context than did vehicle-treated rats. This pattern occurred even when vehicle rats were given double the amount of extinction training, and when FGF2-treated rats were given equivalent exposure to the extinction context. These results show that FGF2 facilitates long-term extinction and attenuates relapse, and thus highlight its potential as a novel pharmacological adjunct to exposure therapy.

  9. Evaporation-reducing Culture Condition Increases the Reproducibility of Multicellular Spheroid Formation in Microtiter Plates.

    PubMed

    Das, Viswanath; Fürst, Tomáš; Gurská, Soňa; Džubák, Petr; Hajdúch, Marián

    2017-03-07

    Tumor models that closely imitate in vivo conditions are becoming increasingly popular in drug discovery and development for the screening of potential anti-cancer drugs. Multicellular tumor spheroids (MCTSes) effectively mimic the physiological conditions of solid tumors, making them excellent in vitro models for lead optimization and target validation. Out of the various techniques available for MCTS culture, the liquid-overlay method on agarose is one of the most inexpensive methods for MCTS generation. However, the reliable transfer of MCTS cultures using liquid-overlay for high-throughput screening may be compromised by a number of limitations, including the coating of microtiter plates (MPs) with agarose and the irreproducibility of uniform MCTS formation across wells. MPs are significantly prone to edge effects that result from excessive evaporation of medium from the exterior of the plate, preventing the use of the entire plate for drug tests. This manuscript provides detailed technical improvements to the liquid-overlay technique to increase the scalability and reproducibility of uniform MCTS formation. Additionally, details on a simple, semi-automatic, and universally applicable software tool for the evaluation of MCTS features after drug treatment is presented.

  10. Dehalogenation and biodegradation of brominated phenols and benzoic acids under iron-reducing, sulfidogenic, and methanogenic conditions.

    PubMed Central

    Monserrate, E; Häggblom, M M

    1997-01-01

    The anaerobic biodegradation of monobrominated phenols and benzoic acids by microorganisms enriched from marine and estuarine sediments was determined in the presence of different electron acceptors [i.e., Fe(III), SO4(2-), or HCO3-]. Under all conditions tested, the bromophenol isomers were utilized without a lengthy lag period whereas the bromobenzoate isomers were utilized only after a lag period of 23 to 64 days. 2-Bromophenol was debrominated to phenol, with the subsequent utilization of phenol under all three reducing conditions. Debromination of 3-bromophenol and 4-bromophenol was also observed under sulfidogenic and methanogenic conditions but not under iron-reducing conditions. In the bromobenzoate-degrading cultures, no intermediates were observed under any of the conditions tested. Debromination rates were higher under methanogenic conditions than under sulfate-reducing or iron-reducing conditions. The stoichiometric reduction of sulfate or Fe(III) and the utilization of bromophenols and phenol indicated that biodegradation was coupled to sulfate or iron reduction, respectively. The production of phenol as a transient intermediate demonstrates that reductive dehalogenation is the initial step in the biodegradation of bromophenols under iron- and sulfate-reducing conditions. PMID:9480645

  11. Tetraglyme Coatings Reduce Fibrinogen and von Willebrand Factor Adsorption and Platelet Adhesion under Both Static and Flow Conditions

    PubMed Central

    Zhang, Min; Horbett, Thomas A.

    2013-01-01

    Previous studies have showed that radio-frequency plasma deposited tetraglyme coatings greatly reduced fibrinogen adsorption (ΓFg) from highly diluted plasmas (0.1% and 1%) and subsequent platelet adhesion under static conditions. In this study, the protein resistant properties of tetraglyme were re-examined with high-concentration plasma, and subsequent platelet adhesion was measured under both static and flow conditions. The resistance of tetraglyme to vWf adsorption (ΓvWf) and the role of vWf in platelet adhesion under flow were also investigated. ΓFg and ΓvWf were measured with 125I radiolabeled proteins. Flow studies were done at shear rates of 50 or 500 s−1 by passing a platelet/red cell suspension through a GlycoTech flow chamber. When adsorbed from a series of increasing plasma concentrations, the adsorption of both proteins to tetraglyme increased steadily, and did not show a peak at intermediate dilutions, i.e. there was no Vroman effect. When plasma concentration was less than 10%, the tetraglyme surface was highly non-fouling, exhibiting ultralow ΓFg (less than 5 ng/ cm2) and extremely low platelet adhesion under both static and flow conditions. However, when the adsorption was done from 100% plasma, ΓFg was much higher (~ 85 ng/cm2), indicating that tetraglyme surface may not be sufficiently protein-resistant in the physiological environment. To correlate platelet adhesion under flow with ΓFg and ΓvWf, a series of tetraglyme surfaces varying in ether content and protein adsorption was created by varying deposition power. On these surfaces, platelet adhesion at low shear rate depended only on the amount of ΓFg, but under high shear, both ΓFg and ΓvWf affected platelet adhesion. In particular, it was found that ΓvWf must be reduced to less than 0.4 ng/cm2 to achieve ultra low platelet adhesion under high shear. PMID:18496865

  12. Persistent high temperature and low precipitation reduce peat carbon accumulation.

    PubMed

    Bragazza, Luca; Buttler, Alexandre; Robroek, Bjorn J M; Albrecht, Remy; Zaccone, Claudio; Jassey, Vincent E J; Signarbieux, Constant

    2016-12-01

    Extreme climate events are predicted to become more frequent and intense. Their ecological impacts, particularly on carbon cycling, can differ in relation to ecosystem sensitivity. Peatlands, being characterized by peat accumulation under waterlogged conditions, can be particularly sensitive to climate extremes if the climate event increases soil oxygenation. However, a mechanistic understanding of peatland responses to persistent climate extremes is still lacking, particularly in terms of aboveground-belowground feedback. Here, we present the results of a transplantation experiment of peat mesocosms from high to low altitude in order to simulate, during 3 years, a mean annual temperature c. 5 °C higher and a mean annual precipitation c. 60% lower. Specifically, we aim at understanding the intensity of changes for a set of biogeochemical processes and their feedback on carbon accumulation. In the transplanted mesocosms, plant productivity showed a species-specific response depending on plant growth forms, with a significant decrease (c. 60%) in peat moss productivity. Soil respiration almost doubled and Q10 halved in the transplanted mesocosms in combination with an increase in activity of soil enzymes. Spectroscopic characterization of peat chemistry in the transplanted mesocosms confirmed the deepening of soil oxygenation which, in turn, stimulated microbial decomposition. After 3 years, soil carbon stock increased only in the control mesocosms whereas a reduction in mean annual carbon accumulation of c. 30% was observed in the transplanted mesocosms. Based on the above information, a structural equation model was built to provide a mechanistic understanding of the causal connections between peat moisture, vegetation response, soil respiration and carbon accumulation. This study identifies, in the feedback between plant and microbial responses, the primary pathways explaining the reduction in carbon accumulation in response to recurring climate extremes in

  13. Amendment of biochar reduces the release of toxic elements under dynamic redox conditions in a contaminated floodplain soil.

    PubMed

    Rinklebe, Jörg; Shaheen, Sabry M; Frohne, Tina

    2016-01-01

    Biochar (BC) can be used to remediate soils contaminated with potential toxic elements (PTEs). However, the efficiency of BC to immobilize PTEs in highly contaminated floodplain soils under dynamic redox conditions has not been studied up to date. Thus, we have (i) quantified the impact of pre-definite redox conditions on the release dynamics of dissolved aluminum (Al), arsenic (As), cadmium (Cd), copper (Cu), nickel (Ni), and zinc (Zn) in a highly contaminated soil (CS) (non-treated) and in the same soil treated with 10 g kg(-1) biochar based material (CS+BC), and (ii) assessed the efficacy of the material to reduce the concentrations of PTEs in soil solution under dynamic redox conditions using an automated biogeochemical microcosm apparatus. The impact of redox potential (EH), pH, dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), iron (Fe), manganese (Mn), and sulfate (SO4(2-)) on dynamics of PTEs was also determined. The EH was lowered to +68 mV and afterwards increased stepwise to +535 mV. Significant negative correlation between EH and pH in CS and CS+BC was detected. The systematic increase of EH along with decrease of pH favors the mobilization of PTEs in CS and CS+BC. The material addition seems to have little effect on redox processes because pattern of EH/pH and release dynamics of PTEs was basically similar in CS and CS+BC. However, concentrations of dissolved PTEs were considerably lower in CS+BC than in CS which demonstrates that BC is able to decrease concentrations of dissolved PTEs even under dynamic redox conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Microbial community functional structure in response to micro-aerobic conditions in sulfate-reducing sulfur-producing bioreactor.

    PubMed

    Yu, Hao; Chen, Chuan; Ma, Jincai; Xu, Xijun; Fan, Ronggui; Wang, Aijie

    2014-05-01

    Limited oxygen supply to anaerobic wastewater treatment systems had been demonstrated as an effective strategy to improve elemental sulfur (S(0)) recovery, coupling sulfate reduction and sulfide oxidation. However, little is known about the impact of dissolved oxygen (DO) on the microbial functional structures in these systems. We used a high throughput tool (GeoChip) to evaluate the microbial community structures in a biological desulfurization reactor under micro-aerobic conditions (DO: 0.02-0.33 mg/L). The results indicated that the microbial community functional compositions and structures were dramatically altered with elevated DO levels. The abundances of dsrA/B genes involved in sulfate reduction processes significantly decreased (p < 0.05, LSD test) at relatively high DO concentration (DO: 0.33 mg/L). The abundances of sox and fccA/B genes involved in sulfur/sulfide oxidation processes significantly increased (p < 0.05, LSD test) in low DO concentration conditions (DO: 0.09 mg/L) and then gradually decreased with continuously elevated DO levels. Their abundances coincided with the change of sulfate removal efficiencies and elemental sulfur (S(0)) conversion efficiencies in the bioreactor. In addition, the abundance of carbon degradation genes increased with the raising of DO levels, showing that the heterotrophic microorganisms (e.g., fermentative microorganisms) were thriving under micro-aerobic condition. This study provides new insights into the impacts of micro-aerobic conditions on the microbial functional structure of sulfate-reducing sulfur-producing bioreactors, and revealed the potential linkage between functional microbial communities and reactor performance. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  15. Selecting Salient Features in High Feature to Exemplar Ratio Conditions

    DTIC Science & Technology

    2002-03-01

    We present an approach for identifying salient input features in high feature to exemplar ratio conditions. Basically we modify the SNR saliency...screening algorithm to improve the solution of the optimal salient feature subset problem. We propose that applying the SNR method to randomly selected...subsets (SRSS) has a superior potential to identify the salient features than the traditional SNR algorithm has. Two experimental studies are provided

  16. 5-HT1A receptor antagonists reduce food intake and body weight by reducing total meals with no conditioned taste aversion.

    PubMed

    Dill, M Joelle; Shaw, Janice; Cramer, Jeff; Sindelar, Dana K

    2013-11-01

    Serotonin acts through receptors controlling several physiological functions, including energy homeostasis regulation and food intake. Recent experiments demonstrated that 5-HT1A receptor antagonists reduce food intake. We sought to examine the microstructure of feeding with 5-HT1A receptor antagonists using a food intake monitoring system. We also examined the relationship between food intake, inhibition of binding and pharmacokinetic (PK) profiles of the antagonists. Ex vivo binding revealed that, at doses used in this study to reduce food intake, inhibition of binding of a 5-HT1A agonist by ~40% was reached in diet-induced obese (DIO) mice with a trend for higher binding in DIO vs. lean animals. Additionally, PK analysis detected levels from 2 to 24h post-compound administration. Male DIO mice were administered 5-HT1A receptor antagonists LY439934 (10 or 30 mg/kg, p.o.), WAY100635 (3 or 10mg/kg, s.c.), SRA-333 (10 or 30 mg/kg, p.o.), or NAD-299 (3 or 10mg/kg, s.c.) for 3 days and meal patterns were measured. Analyses revealed that for each antagonist, 24-h food intake was reduced through a specific decrease in the total number of meals. Compared to controls, meal number was decreased 14-35% in the high dose. Average meal size was not changed by any of the compounds. The reduction in food intake reduced body weight 1-4% compared to Vehicle controls. Subsequently, a conditioned taste aversion (CTA) assay was used to determine whether the feeding decrease might be an indicator of aversion, nausea, or visceral illness caused by the antagonists. Using a two bottle preference test, it was found that none of the compounds produced a CTA. The decrease in food intake does not appear to be a response to nausea or malaise. These results indicate that 5-HT1A receptor antagonist suppresses feeding, specifically by decreasing the number of meals, and induce weight loss without an aversive side effect.

  17. Deep Neuromuscular Block Improves Surgical Conditions during Bariatric Surgery and Reduces Postoperative Pain: A Randomized Double Blind Controlled Trial

    PubMed Central

    Torensma, Bart; Martini, Chris H.; Boon, Martijn; Olofsen, Erik; in ‘t Veld, Bas; Liem, Ronald S. L.; Knook, Mireille T. T.; Swank, Dingeman J.; Dahan, Albert

    2016-01-01

    Background It remains unknown whether the administration of a deep neuromuscular block (NMB) during bariatric surgery improves surgical conditions and patient outcome. The authors studied the effect of deep versus moderate NMB in laparoscopic bariatric surgery on surgical conditions and postoperative pain. Methods and Results One hundred patients scheduled to undergo elective bariatric surgery were randomized to a deep NMB (post-tetanic-count 2–3) or a moderate NMB (train-of-four 1–2). The quality of the surgical field was scored using the Leiden-Surgical Rating Scale (L-SRS), a 5-point scale ranging from 1 (extremely poor conditions) to 5 (optimal conditions). Three surgeons scored the L-SRS at 10-min intervals during surgery; postoperative pain scores were obtained in the postanesthesia-care-unit (PACU) and on the ward. Mean (95% confidence interval) L-SRS scores in moderate NMB 4.2 (4.0–4.4) versus 4.8 (4.7–4.9) in deep NMB (p < 0.001). Moderate NMB resulted in 17% of scores at L-SRS scores of 1–3, while deep NMB resulted in 100% scores at the high end of the L-SRS (4–5). Deep NMB led to improved pain scores in the PACU (4.6 (4.2–4.9) versus 3.9 (3.6–4.4), p = 0.03) and reduced shoulder pain on the ward (1.8 (1.5–2.1) versus 1.3 (1.1–1.5), p = 0.03). A composite score of pain and opioid use in the PACU favoured deep NMB (p = 0.001). Conclusions In bariatric surgery, deep relaxation has advantages for surgeon and patient. Compared to moderate NMB, deep NMB produced stable and improved surgical conditions with less postoperative pain. PMID:27936214

  18. High Quality Acquisition of Surface Electromyography - Conditioning Circuit Design

    NASA Astrophysics Data System (ADS)

    Shobaki, Mohammed M.; Malik, Noreha Abdul; Khan, Sheroz; Nurashikin, Anis; Haider, Samnan; Larbani, Sofiane; Arshad, Atika; Tasnim, Rumana

    2013-12-01

    The acquisition of Surface Electromyography (SEMG) signals is used for many applications including the diagnosis of neuromuscular diseases, and prosthesis control. The diagnostic quality of the SEMG signal is highly dependent on the conditioning circuit of the SEMG acquisition system. This paper presents the design of an SEMG conditioning circuit that can guarantee to collect high quality signal with high SNR such that it is immune to environmental noise. The conditioning circuit consists of four stages; consisting of an instrumentation amplifier that is used with a gain of around 250; 4th order band pass filter in the 20-500Hz frequency range as the two initial stages. The third stage is an amplifier with adjustable gain using a variable resistance; the gain could be changed from 1000 to 50000. In the final stage the signal is translated to meet the input requirements of data acquisition device or the ADC. Acquisition of accurate signals allows it to be analyzed for extracting the required characteristic features for medical and clinical applications. According to the experimental results, the value of SNR for collected signal is 52.4 dB which is higher than the commercial system, the power spectrum density (PSD) graph is also presented and it shows that the filter has eliminated the noise below 20 Hz.

  19. Hif-1α Knockdown Reduces Glycolytic Metabolism and Induces Cell Death of Human Synovial Fibroblasts Under Normoxic Conditions.

    PubMed

    Del Rey, Manuel J; Valín, Álvaro; Usategui, Alicia; García-Herrero, Carmen M; Sánchez-Aragó, María; Cuezva, José M; Galindo, María; Bravo, Beatriz; Cañete, Juan D; Blanco, Francisco J; Criado, Gabriel; Pablos, José L

    2017-06-16

    Increased glycolysis and HIF-1α activity are characteristics of cells under hypoxic or inflammatory conditions. Besides, in normal O2 environments, elevated rates of glycolysis support critical cellular mechanisms such as cell survival. The purpose of this study was to analyze the contribution of HIF-1α to the energy metabolism and survival of human synovial fibroblasts (SF) under normoxic conditions. HIF-1α was silenced using lentiviral vectors or small-interfering RNA (siRNA) duplexes. Expression analysis by qRT-PCR and western blot of known HIF-1α target genes in hypoxia demonstrated the presence of functional HIF-1α in normoxic SF and confirmed the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a HIF-1α target even in normoxia. HIF-1α silencing induced apoptotic cell death in cultured SF and, similarly, treatment with glycolytic, but not with OXPHOS inhibitors, induced SF death. Finally, in vivo HIF-1α targeting by siRNA showed a significant reduction in the viability of human SF engrafted into a murine air pouch. Our results demonstrate that SF are highly dependent on glycolytic metabolism and that HIF-1α plays a regulatory role in glycolysis even under aerobic conditions. Local targeting of HIF-1α provides a feasible strategy to reduce SF hyperplasia in chronic arthritic diseases.

  20. Reducing the impact of physical inactivity: evidence to support the case for targeting people with chronic mental and physical conditions.

    PubMed

    Everson-Hock, Emma S; Green, Mark A; Goyder, Elizabeth C; Copeland, Robert J; Till, Simon H; Heller, Ben; Hart, Ollie

    2016-06-01

    Recent evidence suggests that small increases in the physical activity of those considered least active can have a bigger health impact than raising levels of those already achieving or close to achieving recommendations. Profiling the characteristics of those who are least active allows for appropriate targeting of interventions. This study therefore examined the characteristics of people in the lowest physical activity bracket. Data were taken from the Collaboration for Leadership in Applied Health Research and Care (CLAHRC) funded 'South Yorkshire Cohort', a longitudinal observational dataset of residents of South Yorkshire, England. Five separate outcomes based on a shortened version of the GPPAQ were used to represent the lowest levels of physical activity. Potential predictors examined were age, sex, body mass index, ethnicity, chronic conditions, current employment and deprivation. Descriptive statistics and logistic regression were conducted. Individuals with chronic mental and physical conditions (fatigue, insomnia, anxiety, depression, diabetes, breathing problems, high blood pressure, heart disease, stroke and cancer) were more likely to report the lowest levels of physical activity across all five outcomes. Demographic variations were also observed. Targeting people with chronic mental and physical conditions has the potential to reduce the impact of physical inactivity. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Species Diversity Improves the Efficiency of Mercury-Reducing Biofilms under Changing Environmental Conditions

    PubMed Central

    von Canstein, Harald; Kelly, Sven; Li, Ying; Wagner-Döbler, Irene

    2002-01-01

    Six mercury-resistant environmental proteobacterial isolates and one genetically modified mercury-resistant Pseudomonas putida strain were analyzed for physiological traits of adaptive relevance in an environment of packed-bed bioreactors designed for the decontamination of mercury-polluted chlor-alkali wastewater. The strains displayed characteristic differences in each trait (i.e., biofilm formation capability, growth rate in mercury contaminated wastewaters, and mercury reduction efficiency). Subsequently, they were immobilized either as a monoculture or as a mixed culture on porous carrier material in packed-bed bioreactors through which different batches of filter-sterilized industrial chlor-alkali wastewater were pumped. In monospecies bioreactors, the mercury retention efficiency was sensitive to rapidly increasing mercury concentrations in the wastewater. Mixed culture biofilms displayed a high mercury retention efficiency that was not affected by rapid increases in mercury or continuously high mercury concentrations. The dynamic in the community composition of the mixed culture bioreactors was determined by ribosomal intergenic spacer polymorphism analysis. Mercury-mediated selective pressure decreased the number of prevalent strains. Microbial diversity was completely restored after easing of the selective pressure. Microbial diversity provides a reservoir of strains with complementary ecological niches that results in a superior bioreactor performance under changing environmental conditions. PMID:12039739

  2. Reduced vision in highly myopic eyes without ocular pathology: the ZOC-BHVI high myopia study.

    PubMed

    Jong, Monica; Sankaridurg, Padmaja; Li, Wayne; Resnikoff, Serge; Naidoo, Kovin; He, Mingguang

    2017-07-11

    The aim was to investigate the relationship of the magnitude of myopia with visual acuity in highly myopic eyes without ocular pathology. Twelve hundred and ninety-two highly myopic eyes (up to -6.00 DS both eyes, no astigmatic cut-off) with no ocular pathology from the ZOC-BHVI high myopia study in China, had cycloplegic refraction, followed by subjective refraction and visual acuities and axial length measurement. Two logistic regression models were undertaken to test the association of age, gender, refractive error, axial length and parental myopia with reduced vision. Mean group age was 19.0 ± 8.6 years; subjective spherical equivalent refractive error was -9.03 ± 2.73 D; objective spherical equivalent refractive error was -8.90 ± 2.60 D and axial length was 27.0 ± 1.3 mm. Using visual acuity, 82.4 per cent had normal vision, 16.0 per cent had mildly reduced vision, 1.2 per cent had moderately reduced vision, 0.3 per cent had severely reduced vision and no subjects were blind. The percentage with reduced vision increased with spherical equivalent to 74.5 per cent from -15.00 to -39.99 D, axial length to 67.7 per cent of eyes from 30.01 to 32.00 mm and age to 22.9 per cent of those 41 years and over. Spherical equivalent and axial length were significantly associated with reduced vision (p < 0.0001). Age and parental myopia were not significantly associated with reduced vision. Gender was significant for one model (p = 0.04). Mildly reduced vision is common in high myopia without ocular pathology and is strongly correlated with greater magnitudes of refractive error and axial length. Better understanding is required to minimise reduced vision in high myopes. © 2017 Optometry Australia.

  3. Atmospheric conditions during high ragweed pollen concentrations in Zagreb, Croatia

    NASA Astrophysics Data System (ADS)

    Prtenjak, Maja Telišman; Srnec, Lidija; Peternel, Renata; Madžarević, Valentina; Hrga, Ivana; Stjepanović, Barbara

    2012-11-01

    We examined the atmospheric conditions favourable to the occurrence of maximum concentrations of ragweed pollen with an extremely high risk of producing allergy. Over the 2002-2009 period, daily pollen data collected in Zagreb were used to identify two periods of high pollen concentration (> 600 grains/m3) for our analysis: period A (3-4 September 2002) and period B (6-7 September 2003). Synoptic conditions in both periods were very similar: Croatia was under the influence of a lower sector high pressure system moving slowly eastward over Eastern Europe. During the 2002-2009 period, this type of weather pattern (on ~ 70% of days), in conjunction with almost non-gradient surface pressure conditions in the area (on ~ 30% of days) characterised days when the daily pollen concentrations were higher than 400 grains/m3. Numerical experiments using a mesoscale model at fine resolution showed successful multi-day simulations reproducing the local topographic influence on wind flow and in reasonable agreement with available observations. According to the model, the relatively weak synoptic flow (predominantly from the eastern direction) allowed local thermal circulations to develop over Zagreb during both high pollen episodes. Two-hour pollen concentrations and 48-h back-trajectories indicated that regional-range transport of pollen grains from the central Pannonian Plain was the cause of the high pollen concentrations during period A. During period B, the north-westward regional-range transport in Zagreb was supplemented significantly by pronounced horizontal recirculation of pollen grains. This recirculation happened within the diurnal local circulation over the city, causing a late-evening increase in pollen concentration.

  4. Atmospheric conditions during high ragweed pollen concentrations in Zagreb, Croatia.

    PubMed

    Prtenjak, Maja Telišman; Srnec, Lidija; Peternel, Renata; Madžarević, Valentina; Hrga, Ivana; Stjepanović, Barbara

    2012-11-01

    We examined the atmospheric conditions favourable to the occurrence of maximum concentrations of ragweed pollen with an extremely high risk of producing allergy. Over the 2002-2009 period, daily pollen data collected in Zagreb were used to identify two periods of high pollen concentration (> 600 grains/m(3)) for our analysis: period A (3-4 September 2002) and period B (6-7 September 2003). Synoptic conditions in both periods were very similar: Croatia was under the influence of a lower sector high pressure system moving slowly eastward over Eastern Europe. During the 2002-2009 period, this type of weather pattern (on ~ 70% of days), in conjunction with almost non-gradient surface pressure conditions in the area (on ~ 30% of days) characterised days when the daily pollen concentrations were higher than 400 grains/m(3). Numerical experiments using a mesoscale model at fine resolution showed successful multi-day simulations reproducing the local topographic influence on wind flow and in reasonable agreement with available observations. According to the model, the relatively weak synoptic flow (predominantly from the eastern direction) allowed local thermal circulations to develop over Zagreb during both high pollen episodes. Two-hour pollen concentrations and 48-h back-trajectories indicated that regional-range transport of pollen grains from the central Pannonian Plain was the cause of the high pollen concentrations during period A. During period B, the north-westward regional-range transport in Zagreb was supplemented significantly by pronounced horizontal recirculation of pollen grains. This recirculation happened within the diurnal local circulation over the city, causing a late-evening increase in pollen concentration.

  5. Photosynthesis, light use efficiency, and yield of reduced-chlorophyll soybean mutants in field conditions

    USDA-ARS?s Scientific Manuscript database

    Reducing chlorophyll (chl) content may improve the conversion efficiency of absorbed radiation into biomass (ec) and therefore yield in dense monoculture crops by improving light penetration and distribution within the canopy. Modeling suggests that reducing chl content may also reduce leaf temperat...

  6. Impact of KIR and HLA Genotypes on Outcomes after Reduced-Intensity Conditioning Hematopoietic Cell Transplantation

    PubMed Central

    Sobecks Ronald, M; Tao, Wang; Medhat, Askar; Gallagher Meighan, M; Michael, Haagenson; Stephen, Spellman; Marcelo, Fernandez-Vina; Karl-Johan, Malmberg; Carlheinz, Muller; Minoo, Battiwalla; James, Gajewski; Verneris Michael, R; Olle, Ringden; Marino Susana, R; Stella, Davies; Jason, Dehn; Martin, Bornhäuser; Yoshihiro, Inamoto; Ann, Woolfrey; Peter, Shaw; Marilyn, Pollack; Daniel, Weisdorf; Jeffrey, Miller; Hurley Carolyn, K; Lee Stephanie, J; Hsu Katharine, C

    2015-01-01

    Natural killer (NK) cells are regulated killer immunoglobulin-like receptor (KIR) interactions with HLA class I ligands. Several models of NK reactivity have been associated with improved outcomes following myeloablative allogeneic hematopoietic cell transplantation (HCT), but this issue has not been rigorously addressed in reduced-intensity conditioning (RIC) unrelated donor (URD) HCT. We studied 909 patients undergoing RIC-URD HCT. Patients with acute myeloid leukemia (AML, n=612) lacking ≥1 KIR ligands experienced higher grade III–IV acute graft-vs.-host disease (GvHD) (HR 1.6, 95%CI 1.16–2.28, p=0.005) compared to those with all ligands present. Absence of HLA-C2 for donor KIR2DL1 was associated with higher grade II–IV (HR 1.4, p=0.002) and III–IV acute GvHD (HR 1.5, p=0.01) compared to HLA-C2+patients. AML patients with KIR2DS1+, HLA-C2 homozygous donors had greater treatment-related mortality compared to others (HR 2.4, 95%CI 1.4–4.2, p=0.002), but did not experience lower relapse. There were no significant associations with outcomes for AML when assessing donor activating KIRs or centromeric KIR content, nor for any donor-recipient KIR-HLA assessments in patients with myelodysplastic syndrome (n=297). KIR-HLA combinations in RIC-URD HCT recapitulate some but not all KIR-HLA effects observed in myeloablative HCT. PMID:25960307

  7. ED triage pain protocol reduces time to receiving analgesics in patients with painful conditions.

    PubMed

    Barksdale, Aaron Nathan; Hackman, Jeff Lee; Williams, Karen; Gratton, Matt Christopher

    2016-12-01

    Studies suggest that collaborative nursing protocols initiated in triage improve emergency department (ED) throughput and decrease time to treatment. The objective of the study is to determine if an ED triage pain protocol improves time to provision of analgesics. Retrospective data abstracted via electronic medical record of patients at a safety net facility with 67 000 annual adult visits. Patients older than 18 years who presented to the ED between March 1, 2011, and May 31, 2013, with 1 of 6 conditions were included: back pain, dental pain, extremity trauma, sore throat, ear pain, or pain from an abscess. A 3-month orientation to an ED nurse-initiated pain protocol began on March 1, 2012. Nurses administered oral analgesics per protocol, beginning with acetaminophen or ibuprofen and progressing to oxycodone. Preimplementation and postimplementation analyses examined differences in time to analgesics. Multivariable analysis modeled time to analgesics as a function of patient factors. Over a 27-month period, 23 409 patients were included: 13 112 received pain medications and 10 297 did not. A total of 12 240 (52%) were male, 12 578 (54%) were African American, and 7953 (34%) were white, with a mean (SD) age of 39 years (13 years). The pain protocol was used in 1002 patients. There was a significant change in mean time (minutes) to provision of analgesics between preimplementation (238) and postimplementation (168) (P < .0001). Linear regression showed the protocol-delivered medications to younger patients and of lower acuity in a reduced time. Variables not related to time to provision of medication included sex, payer, and race. Emergency department triage pain protocol decreased time to provision of pain medications and did so without respect to payer category, sex, or race. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. High CD3+ and CD34+ peripheral blood stem cell grafts content is associated with increased risk of graft-versus-host disease without beneficial effect on disease control after reduced-intensity conditioning allogeneic transplantation from matched unrelated donors for acute myeloid leukemia — an analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation

    PubMed Central

    Czerw, Tomasz; Labopin, Myriam; Schmid, Christoph; Cornelissen, Jan J.; Chevallier, Patrice; Blaise, Didier; Kuball, Jürgen; Vigouroux, Stephane; Garban, Frédéric; Lioure, Bruno; Fegueux, Nathalie; Clement, Laurence; Sandstedt, Anna; Maertens, Johan; Guillerm, Gaëlle; Bordessoule, Dominique

    2016-01-01

    Inconsistent results have been reported regarding the influence of graft composition on the incidence of graft versus host disease (GVHD), disease control and survival after reduced-intensity conditioning (RIC) allogeneic peripheral blood stem cell transplantation (allo-PBSCT). These discrepancies may be at least in part explained by the differences in disease categories, disease status at transplant, donor type and conditioning. The current retrospective EBMT registry study aimed to analyze the impact of CD3+ and CD34+ cells dose on the outcome of RIC allo-PBSCT in patients with acute myelogenous leukemia (AML) in first complete remission, allografted from HLA-matched unrelated donors (10 of 10 match). We included 203 adults. In univariate analysis, patients transplanted with the highest CD3+ and CD34+ doses (above the third quartile cut-off point values, >347 × 10^6/kg and >8.25 × 10^6 /kg, respectively) had an increased incidence of grade III-IV acute (a) GVHD (20% vs. 6%, P = .003 and 18% vs. 7%, P = .02, respectively). There was no association between cellular composition of grafts and transplant-related mortality, AML relapse, incidence of chronic GVHD and survival. Neither engraftment itself nor the kinetics of engraftment were affected by the cell dose. In multivariate analysis, CD3+ and CD34+ doses were the only adverse predicting factors for grade III-IV aGVHD (HR = 3.6; 95%CI: 1.45-9.96, P = .006 and 2.65 (1.07-6.57), P = .04, respectively). These results suggest that careful assessing the CD3+ and CD34+ graft content and tailoring the cell dose infused may help in reducing severe acute GVHD risk without negative impact on the other transplantation outcomes. PMID:27036034

  9. High tolerance to high-light conditions for the protected species Ariocarpus kotschoubeyanus (Cactaceae).

    PubMed

    Arroyo-Pérez, Erika; Flores, Joel; González-Salvatierra, Claudia; Matías-Palafox, María L; Jiménez-Sierra, Cecilia

    2017-01-01

    We determined the seasonal ecophysiological performance under perennial plants and under high solar radiation for adult individuals from the 'living rock' cactus Ariocarpus kotschoubeyanus, which occurs equally under nurse plants and in open spaces. We evaluated the effective quantum yield of photosystem II (ΦPSII) and the dissipation of thermal energy [non-photochemical quenching (NPQ)] thorough the year. The maximum apparent electron transport rate (ETRmax) and the saturating photosynthetically active photon flux density for PSII (PFDsat) were also determined from rapid light curves. We found that although the ΦPSII was higher in shaded sites under potential nurse plants than in exposed sites, all values were close to the optimal value of 0.83. The high ΦPSII found for A. kotschoubeyanus plants suggests that they use a great proportion of the absorbed light for photosynthesis, under nurse plants as well as in open spaces. We also found higher NPQ values in exposed sites than in shaded ones but only in Autumn, thus reducing the risk of photoinhibition. In addition, the PFDsat was higher in exposed sites than in shaded ones in Spring, Summer and Autumn, but in Winter there were no differences between treatments. We also found high saturating light levels for ETR (PFDsat higher than 1378 μmol m(-2) s(-1)) in all seasons but in winter for shaded and non-shaded plants. Our findings indicate that A. kotschoubeyanus plants use a great proportion of the light that they absorb for photosynthesis. This high tolerance to high-light conditions could explain why A. kotschoubeyanus do not show preferences for protected sites under nurse plants.

  10. High tolerance to high-light conditions for the protected species Ariocarpus kotschoubeyanus (Cactaceae)

    PubMed Central

    Arroyo-Pérez, Erika; González-Salvatierra, Claudia; Matías-Palafox, María L.; Jiménez-Sierra, Cecilia

    2017-01-01

    Abstract We determined the seasonal ecophysiological performance under perennial plants and under high solar radiation for adult individuals from the ‘living rock’ cactus Ariocarpus kotschoubeyanus, which occurs equally under nurse plants and in open spaces. We evaluated the effective quantum yield of photosystem II (ΦPSII) and the dissipation of thermal energy [non-photochemical quenching (NPQ)] thorough the year. The maximum apparent electron transport rate (ETRmax) and the saturating photosynthetically active photon flux density for PSII (PFDsat) were also determined from rapid light curves. We found that although the ΦPSII was higher in shaded sites under potential nurse plants than in exposed sites, all values were close to the optimal value of 0.83. The high ΦPSII found for A. kotschoubeyanus plants suggests that they use a great proportion of the absorbed light for photosynthesis, under nurse plants as well as in open spaces. We also found higher NPQ values in exposed sites than in shaded ones but only in Autumn, thus reducing the risk of photoinhibition. In addition, the PFDsat was higher in exposed sites than in shaded ones in Spring, Summer and Autumn, but in Winter there were no differences between treatments. We also found high saturating light levels for ETR (PFDsat higher than 1378 μmol m−2 s−1) in all seasons but in winter for shaded and non-shaded plants. Our findings indicate that A. kotschoubeyanus plants use a great proportion of the light that they absorb for photosynthesis. This high tolerance to high-light conditions could explain why A. kotschoubeyanus do not show preferences for protected sites under nurse plants. PMID:28729902

  11. High resolution Ge/Li/ spectrometer reduces rate-dependent distortions at high counting rates

    NASA Technical Reports Server (NTRS)

    Brenner, R.; Larsen, R. N.; Mann, H. M.; Rudnick, S. J.; Sherman, I. S.; Strauss, M. G.

    1968-01-01

    Modified spectrometer system with a low-noise preamplifier reduces rate-dependent distortions at high counting rates, 25,000 counts per second. Pole-zero cancellation minimizes pulse undershoots due to multiple time constants, baseline restoration improves resolution and prevents spectral shifts.

  12. Anaerobic Biodegradation Of Methyl tert-Butyl Ether Under Iron-Reducing Conditions In Batch And Continuous-Flow Cultures

    EPA Science Inventory

    The feasibility of biodegradation of the fuel oxygenate methyl tert-butyl ether (MTBE) under iron-reducing conditions was explored in batch and continuous-flow systems. A porous pot completely-mixed reactor was seeded with diverse cultures and operated under iron-reducing...

  13. Anaerobic Biodegradation Of Methyl tert-Butyl Ether Under Iron-Reducing Conditions In Batch And Continuous-Flow Cultures

    EPA Science Inventory

    The feasibility of biodegradation of the fuel oxygenate methyl tert-butyl ether (MTBE) under iron-reducing conditions was explored in batch and continuous-flow systems. A porous pot completely-mixed reactor was seeded with diverse cultures and operated under iron-reducing...

  14. Embryonic Methamphetamine Exposure Inhibits Methamphetamine Cue Conditioning and Reduces Dopamine Concentrations in Adult N2 Caenorhabditis elegans.

    PubMed

    Katner, Simon N; Neal-Beliveau, Bethany S; Engleman, Eric A

    2016-01-01

    Methamphetamine (MAP) addiction is substantially prevalent in today's society, resulting in thousands of deaths and costing billions of dollars annually. Despite the potential deleterious consequences, few studies have examined the long-term effects of embryonic MAP exposure. Using the invertebrate nematode Caenorhabditis elegans allows for a controlled analysis of behavioral and neurochemical changes due to early developmental drug exposure. The objective of the current study was to determine the long-term behavioral and neurochemical effects of embryonic exposure to MAP in C. elegans. In addition, we sought to improve our conditioning and testing procedures by utilizing liquid filtration, as opposed to agar, and smaller, 6-well testing plates to increase throughput. Wild-type N2 C. elegans were embryonically exposed to 50 μM MAP. Using classical conditioning, adult-stage C. elegans were conditioned to MAP (17 and 500 μM) in the presence of either sodium ions (Na+) or chloride ions (Cl-) as conditioned stimuli (CS+/CS-). Following conditioning, a preference test was performed by placing worms in 6-well test plates spotted with the CS+ and CS- at opposite ends of each well. A preference index was determined by counting the number of worms in the CS+ target zone divided by the total number of worms in the CS+ and CS- target zones. A food conditioning experiment was also performed in order to determine whether embryonic MAP exposure affected food conditioning behavior. For the neurochemical experiments, adult worms that were embryonically exposed to MAP were analyzed for dopamine (DA) content using high-performance liquid chromatography. The liquid filtration conditioning procedure employed here in combination with the use of 6-well test plates significantly decreased the time required to perform these experiments and ultimately increased throughput. The MAP conditioning data found that pairing an ion with MAP at 17 or 500 μM significantly increased the preference

  15. Embryonic Methamphetamine Exposure Inhibits Methamphetamine Cue Conditioning and Reduces Dopamine Concentrations in Adult N2 C. elegans

    PubMed Central

    Katner, S.N.; Neal-Beliveau, B.S.; Engleman, E.A.

    2016-01-01

    Methamphetamine (MAP) addiction is substantially prevalent in today's society, resulting in thousands of deaths and costing billions of dollars annually. Despite the potential deleterious consequences, few studies have examined the long-term effects of embryonic MAP exposure. Using the invertebrate nematode Caenorhabditis elegans (C. elegans) allows for a controlled analysis of behavioral and neurochemical changes due to early developmental drug exposure. The objective of the current studies was to determine the long-term behavioral and neurochemical effects of embryonic exposure to MAP in C. elegans. In addition, we sought to improve our conditioning and testing procedures by utilizing liquid filtration, as opposed to agar, and smaller, 6-well testing plates to increase throughput. Wild-type N2 C. elegans were embryonically exposed to 50 μM MAP. Using classical conditioning, adult-stage C. elegans were conditioned to MAP (17 and 500 μM) in the presence of either sodium ions (Na+) or chloride (Cl-) ions as conditioned stimuli (CS+/CS-). Following conditioning, a preference test was performed by placing worms in 6-well test plates spotted with the CS+ and CS- at opposite ends of each well. A preference index (PI) was determined by counting the number of worms in the CS+ target zone divided by the total number of worms in the CS+ and CS- target zones. A food conditioning experiment was also performed in order to determine if embryonic MAP exposure affected food conditioning behavior. For the neurochemical experiments, adult worms that were embryonically exposed to MAP were analyzed for (dopamine) DA content using high performance liquid chromatography (HPLC). The liquid filtration conditioning procedure employed here in combination with the use 6-well test plates significantly decreased the time required to perform these experiments and ultimately increased throughput. The MAP conditioning data found that pairing an ion with MAP at 17 or 500 μM significantly

  16. Adverse health effects of high-effort/low-reward conditions.

    PubMed

    Siegrist, J

    1996-01-01

    In addition to the person-environment fit model (J. R. French, R. D. Caplan, & R. V. Harrison, 1982) and the demand-control model (R. A. Karasek & T. Theorell, 1990), a third theoretical concept is proposed to assess adverse health effects of stressful experience at work: the effort-reward imbalance model. The focus of this model is on reciprocity of exchange in occupational life where high-cost/low-gain conditions are considered particularly stressful. Variables measuring low reward in terms of low status control (e.g., lack of promotion prospects, job insecurity) in association with high extrinsic (e.g., work pressure) or intrinsic (personal coping pattern, e.g., high need for control) effort independently predict new cardiovascular events in a prospective study on blue-collar men. Furthermore, these variables partly explain prevalence of cardiovascular risk factors (hypertension, atherogenic lipids) in 2 independent studies. Studying adverse health effects of high-effort/low-reward conditions seems well justified, especially in view of recent developments of the labor market.

  17. High nitrate supply reduces growth in maize, from cell to whole plant.

    PubMed

    Saiz-Fernández, Iñigo; De Diego, Nuria; Sampedro, Maria Carmen; Mena-Petite, Amaia; Ortiz-Barredo, Amaia; Lacuesta, Maite

    2015-01-15

    Nitrogen (N) is an essential macronutrient that limits agricultural productivity, and both low and high N supply have been suggested to alter plant growth. The overall aim of this work is to study the impact of nitrate (NO3(-)) in maize yield and the possible causes that induce this alteration. High NO3(-) doses did not increase the yield of maize grown neither in the field nor under controlled conditions. In fact, plants grown under controlled conditions for 45 days with NO3(-) concentrations over 5mM showed a decrease in biomass production. This reduction was perceptible in shoots prior to roots, where phytomer expansion was reduced. Cell size and number were also reduced in the leaves of plants with high NO3(-). This alteration was correlated with the increase of 1-aminocyclopropane-1-carboxylic acid in leaves, which was probably translocated from the roots in order to synthesize ethylene. Cytokinins (CKs) also showed a relevant role in this inhibitory effect, increasing in high NO3(-) plants with a reduction in root and shoot growth, inhibition of apical dominance and a strong decrease of leaf expansion, symptoms described previously as "CK syndrome". We propose that high NO3(-) inhibits maize growth by causing hormonal alterations that modify plant growth from cell to whole plant. Copyright © 2014 Elsevier GmbH. All rights reserved.

  18. High concentrations of glucose reduce the oxidative metabolism of dog neutrophils in vitro

    PubMed Central

    2013-01-01

    Background Dogs are commonly affected by hyperglycemic conditions. Hyperglycemia compromises the immune response and favors bacterial infections; however, reports on the effects of glucose on neutrophil oxidative metabolism and apoptosis are conflicting in humans and rare in dogs. Considering the many complex factors that affect neutrophil oxidative metabolism in vivo, we investigated in vitro the specific effect of high concentrations of glucose on superoxide production and apoptosis rate in neutrophils from healthy dogs. Results The capacity of the neutrophils to reduce tetrazolium nitroblue decreased significantly in the higher concentration of glucose (15.13 ± 9.73% (8 mmol/L) versus 8.93 ± 5.71% (16 mmol/L)). However, there were no changes in tetrazolium nitroblue reduction at different glucose concentrations when the neutrophils were first activated with phorbol myristate acetate. High concentrations of glucose did not affect the viability and apoptosis rate of canine neutrophils either with or without prior camptothecin stimulation. This study provides the first evidence that high concentrations of glucose inhibit the oxidative metabolism of canine neutrophils in vitro in a manner similar to that which occurs in humans, and that the decrease in superoxide production did not increase the apoptosis rate. Conclusions A high concentration of glucose reduces the oxidative metabolism of canine neutrophils in vitro. It is likely that glucose at high concentrations rapidly affects membrane receptors responsible for the activation of NADPH oxidase in neutrophils; therefore, the nonspecific immune response can be compromised in dogs with acute and chronic hyperglycemic conditions. PMID:23388121

  19. High Technology Centrifugal Compressor for Commercial Air Conditioning Systems

    SciTech Connect

    Ruckes, John

    2006-04-15

    R&D Dynamics, Bloomfield, CT in partnership with the State of Connecticut has been developing a high technology, oil-free, energy-efficient centrifugal compressor called CENVA for commercial air conditioning systems under a program funded by the US Department of Energy. The CENVA compressor applies the foil bearing technology used in all modern aircraft, civil and military, air conditioning systems. The CENVA compressor will enhance the efficiency of water and air cooled chillers, packaged roof top units, and other air conditioning systems by providing an 18% reduction in energy consumption in the unit capacity range of 25 to 350 tons of refrigeration The technical approach for CENVA involved the design and development of a high-speed, oil-free foil gas bearing-supported two-stage centrifugal compressor, CENVA encompassed the following high technologies, which are not currently utilized in commercial air conditioning systems: Foil gas bearings operating in HFC-134a; Efficient centrifugal impellers and diffusers; High speed motors and drives; and System integration of above technologies. Extensive design, development and testing efforts were carried out. Significant accomplishments achieved under this program are: (1) A total of 26 builds and over 200 tests were successfully completed with successively improved designs; (2) Use of foil gas bearings in refrigerant R134a was successfully proven; (3) A high speed, high power permanent magnet motor was developed; (4) An encoder was used for signal feedback between motor and controller. Due to temperature limitations of the encoder, the compressor could not operate at higher speed and in turn at higher pressure. In order to alleviate this problem a unique sensorless controller was developed; (5) This controller has successfully been tested as stand alone; however, it has not yet been integrated and tested as a system; (6) The compressor successfully operated at water cooled condensing temperatures Due to temperature

  20. Ultrafilter Conditions for High Level Waste Sludge Processing

    SciTech Connect

    Geeting, John GH; Hallen, Richard T.; Peterson, Reid A.

    2006-08-28

    An evaluation of the optimal filtration conditions was performed based on test data obtained from filtration of a High Level Waste Sludge sample from the Hanford tank farms. This evaluation was performed using the anticipated configuration for the Waste Treatment Plant at the Hanford site. Testing was performed to identify the optimal pressure drop and cross flow velocity for filtration at both high and low solids loading. However, this analysis indicates that the actual filtration rate achieved is relatively insensitive to these conditions under anticipated operating conditions. The maximum filter flux was obtained by adjusting the system control valve pressure from 400 to 650 kPa while the filter feed concentration increased from 5 to 20 wt%. However, operating the system with a constant control valve pressure drop of 500 kPa resulted in a less than 1% reduction in the average filter flux. Also note that allowing the control valve pressure to swing as much as +/- 20% resulted in less than a 5% decrease in filter flux.

  1. High explosive violent reaction (HEVR) from slow heating conditions

    SciTech Connect

    Vigil, A.S.

    1999-03-01

    The high explosives (HEs) developed and used at the Los Alamos National Laboratory are designed to be insensitive to impact and thermal insults under all but the most extreme conditions. Nevertheless, violent reactions do occasionally occur when HE is involved in an accident. The HE response is closely dependent on the type of external stimulus that initiates the reaction. For example, fast heating of conventional HE will probably result in fairly benign burning, while long-term, slow heating of conventional HE is more likely to produce an HEVR that will do much more damage to the immediate surroundings. An HEVR (High Explosive Violent Reaction) can be defined as the rapid release of energy from an explosive that ranges from slightly faster than a deflagration (very rapid burning) to a reaction that approaches a detonation. A number of thermal analyses have been done to determine slow heat/cook-off conditions that produce HE self-heating that can build up to a catastrophic runaway reaction. The author specifies the conditions that control reaction violence, describes experiments that produced an HEVR, describes analyses done to determine a heating rate threshold for HEVR, and lists possible HEVR situations.

  2. Melt Conditioning of Light Metals by Application of High Shear for Improved Microstructure and Defect Control

    NASA Astrophysics Data System (ADS)

    Patel, Jayesh B.; Yang, Xinliang; Mendis, Chamini L.; Fan, Zhongyun

    2017-04-01

    Casting is the first step toward the production of majority of metal products whether the final processing step is casting or other thermomechanical processes such as extrusion or forging. The high shear melt conditioning provides an easily adopted pathway to producing castings with a more uniform fine-grained microstructure along with a more uniform distribution of the chemical composition leading to fewer defects as a result of reduced shrinkage porosities and the presence of large oxide films through the microstructure. The effectiveness of high shear melt conditioning in improving the microstructure of processes used in industry illustrates the versatility of the high shear melt conditioning technology. The application of high shear process to direct chill and twin roll casting process is demonstrated with examples from magnesium melts.

  3. Design and realization of high voltage disconnector condition monitoring system

    NASA Astrophysics Data System (ADS)

    Shi, Jinrui; Xu, Tianyang; Yang, Shuixian; Li, Buoyang

    2017-08-01

    The operation status of the high voltage disconnector directly affects the safe and stable operation of the power system. This article uses the wireless frequency hopping communication technology of the communication module to achieve the temperature acquisition of the switch contacts and high voltage bus, to introduce the current value of the loop in ECS, and judge the operation status of the disconnector by considering the ambient temperature, calculating the temperature rise; And through the acquisition of the current of drive motor in the process of switch closing and opening, and fault diagnosis of the disconnector by analyzing the change rule of the drive motor current, the condition monitoring of the high voltage disconnector is realized.

  4. High-Latitude Ionospheric Dynamics During Conditions of Northward IMF

    NASA Technical Reports Server (NTRS)

    Sharber, J. R.

    1996-01-01

    In order to better understand the physical processes operating during conditions of northward interplanetary magnetic field (IMF), in situ measurements from the Dynamics Explorer-2 (low altitude) polar satellite and simultaneous observations from the auroral imager on the Dynamics Explorer-1 (high altitude) satellite were used to investigate the relationships between optical emissions, particle precipitation, and convective flows in the high-latitude ionosphere. Field aligned current and convective flow patterns during IMF north include polar cap arcs, the theta aurora or transpolar arc, and the 'horse-collar' aurora. The initial part of the study concentrated on the electrodynamics of auroral features in the horse-collar aurora, a contracted but thickened emission region in which the dawn and dusk portions can spread to very high latitudes, while the latter part focused on the evolution of one type of IMF north auroral pattern to another, specifically the quiet-time horse-collar pattern to a theta aurora.

  5. High rate material behaviour at hot forming conditions

    NASA Astrophysics Data System (ADS)

    Meyer, Lothar W.; Kuprin, Corinna; Halle, Thorsten

    2009-03-01

    Modern processes of hot forming use very high strain rates and large, mostly incrementally applied strains. For the simulation of such forming processes relevant material data are needed, which have to be recorded under accordant forming conditions. This places extraordinary demands on the experimental technique, because high temperatures, high strain rates and large strains have to be implemented simultaneously. In the following contribution such an aligned experimental technique is introduced. In order to apply a very large range of strain rate, compression tests are performed using different technical equipment up to a drop tower and Hopkinson pressure bar. To reach large plastic strains, a hot torsion test was developed, which allowed true plastic shear strains up to 10 at strain rates in the order of 100 1/s at hot forming temperatures.

  6. Collision condition indicted by High Pressure Phases in a Chondrite

    NASA Astrophysics Data System (ADS)

    Kato, Y.; Sekine, T.; Kayama, M.; Miyahara, M.; Yamaguchi, A.

    2012-12-01

    It has been generally recognized that there were many collisions during planetary accretion. Chondrites include the materials at the time of formation of the solar system. It is essential to unravel the shock history in meteorites and the parent planet in order to understand such collisional processes. In this study, we investigate a thin section of ordinary chondrite Y-790729 classified as L6 in which high-pressure minerals are found in the about 620-μm-wide shock vein. The mineralogical and chemical features give us detailed information to constrain the shock conditions. We have tried to constrain the P-T condition from the viewpoints of the mineral assemblage and cathodoluminescense (CL) spectroscopy. Y-790729 consists mostly of olivine and pyroxene and has shock veins. To identify high pressure phases, we used an optical microscope, a scanning electron microscope (SEM), micro Raman spectroscopy, and electron probe micro analyzer (EPMA). In addition, scanning electron microscopy-cathodoluminescence (SEM-CL) analysis, detectable shock-induced defect centers, was used to characterize the shock metamorphism in feldspar minerals. The presence of shock vein, maskelynite, and high pressure phases confirms shock record. 7 high pressure phases of ringwoodite, high-pressure clinoenstatite (HPC), majorite, merrillite, lingunite, high-pressure chromite and akimotoite were found in this section. All of them exist only in a shock vein, but maskelynite occurs everywhere in the section. From these observations, it is obvious that the shock vein experienced the high pressure and high temperature generated by shock wave. If some of the high pressure minerals are equilibrated, the P-T condition can be estimated. Based on the equilibrium phase diagram of MgSiO3 polymorphs (Presnall. 1995), the P-T conditions for crystallization of majorite, HPC and akimotoite is about 17 GPa and 1600 oC, because the compositions of the three phases are close to MgSiO3. It is consistent with the

  7. High Accuracy Temperature Measurements Using RTDs with Current Loop Conditioning

    NASA Technical Reports Server (NTRS)

    Hill, Gerald M.

    1997-01-01

    To measure temperatures with a greater degree of accuracy than is possible with thermocouples, RTDs (Resistive Temperature Detectors) are typically used. Calibration standards use specialized high precision RTD probes with accuracies approaching 0.001 F. These are extremely delicate devices, and far too costly to be used in test facility instrumentation. Less costly sensors which are designed for aeronautical wind tunnel testing are available and can be readily adapted to probes, rakes, and test rigs. With proper signal conditioning of the sensor, temperature accuracies of 0.1 F is obtainable. For reasons that will be explored in this paper, the Anderson current loop is the preferred method used for signal conditioning. This scheme has been used in NASA Lewis Research Center's 9 x 15 Low Speed Wind Tunnel, and is detailed.

  8. An intermediate alemtuzumab schedule reduces the incidence of mixed chimerism following reduced-intensity conditioning hematopoietic cell transplantation for hemophagocytic lymphohistiocytosis.

    PubMed

    Marsh, Rebecca A; Kim, Mi-Ok; Liu, Chunyan; Bellman, Denise; Hart, Laura; Grimley, Michael; Kumar, Ashish; Jodele, Sonata; Myers, Kasiani C; Chandra, Sharat; Leemhuis, Tom; Mehta, Parinda A; Bleesing, Jack J; Davies, Stella M; Jordan, Michael B; Filipovich, Alexandra H

    2013-11-01

    Reduced-intensity conditioning (RIC) improves the outcomes of hematopoietic cell transplantation (HCT) in patients with hemophagocytic lymphohistiocytosis (HLH). Proximal (ie, close to graft infusion) dosing of alemtuzumab is associated with a high incidence of mixed chimerism, whereas distal (ie, distant from graft infusion) dosing is associated with less mixed chimerism but more acute graft-versus-host disease (GVHD). The alemtuzumab dose per kilogram of body weight also influences these outcomes. We hypothesized that an intermediate alemtuzumab dosing schedule would reduce mixed chimerism and maintain a low incidence of acute GVHD. In this study, 24 consecutive HCTs were performed in patients with HLH or a related disorder using a novel intermediate alemtuzumab schedule of 1 mg/kg starting on day -14. The cumulative incidences (CIs) of mixed chimerism, upfront acute GVHD grades II-IV, and receipt of additional hematopoietic cell products after HCT were compared in patients treated with a distal alemtuzumab schedule (n = 15) and those treated with a proximal alemtuzumab schedule (n = 33). All patients received fludarabine and melphalan. The CI of mixed chimerism was 31% in the intermediate group, 72% in the proximal group (P < .01), and 75% in the distal group patients who received ≥2 mg/kg alemtuzumab (P = .03). The CI of acute GVHD grades II-IV before the development of mixed chimerism was 4% in the intermediate group, 0% in the proximal group, and 13% in the distal group (P = .04, proximal versus distal). The 1-year CI of administration of additional hematopoietic cell products for mixed chimerism (donor lymphocyte infusion ± hematopoietic stem cell boost ± repeat HCT) was 14% in the intermediate group, 53% in the proximal group (P = .01), and 38% in the distal ≥2 mg/kg alemtuzumab group (P = .02). Our findings indicate that intermediate RIC reduces the incidence of mixed chimerism, is associated with a low incidence of upfront acute

  9. Polar and high latitude substorms and solar wind conditions

    NASA Astrophysics Data System (ADS)

    Despirak, I. V.; Lyubchich, A. A.; Kleimenova, N. G.

    2014-09-01

    All substorm disturbances observed in polar latitudes can be divided into two types: polar, which are observable at geomagnetic latitudes higher than 70° in the absence of substorms below 70°, and high latitude substorms, which travel from auroral (<70°) to polar (>70°) geomagnetic latitudes. The aim of this study is to compare conditions in the IMF and solar wind, under which these two types of substorms are observable on the basis of data from meridional chain of magnetometers IMAGE and OMNI database for 1995, 2000, and 2006-2011. In total, 105 polar and 55 high latitude substorms were studied. It is shown that polar substorms are observable at a low velocity of solar wind after propagation of a high-speed recurrent stream during the late recovery phase of a magnetic storm. High latitude substorms, in contrast, are observable with a high velocity of solar wind, increased values of the Bz component of the IMF, the Ey component of the electric field, and solar wind temperature and pressure, when a high-speed recurrent stream passes by the Earth.

  10. Active Supervision: An Intervention to Reduce High School Tardiness

    ERIC Educational Resources Information Center

    Johnson-Gros, Kristin N.; Lyons, Elizabeth A.; Griffin, Jennifer R.

    2008-01-01

    One proactive approach to aid in reducing disciplinary problems in schools is implementing Positive Behavior Support (PBS) strategies. To successfully implement PBS school-wide, Sugai and Horner (2002a) emphasize a multisystems perspective, which focuses on school-wide discipline, classroom management, non-classroom settings, and individual…

  11. Active Supervision: An Intervention to Reduce High School Tardiness

    ERIC Educational Resources Information Center

    Johnson-Gros, Kristin N.; Lyons, Elizabeth A.; Griffin, Jennifer R.

    2008-01-01

    One proactive approach to aid in reducing disciplinary problems in schools is implementing Positive Behavior Support (PBS) strategies. To successfully implement PBS school-wide, Sugai and Horner (2002a) emphasize a multisystems perspective, which focuses on school-wide discipline, classroom management, non-classroom settings, and individual…

  12. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    SciTech Connect

    Boeder, A; Zimm, C

    2006-09-30

    Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate

  13. Action of bimetallic nanocatalysts under reaction conditions and during catalysis: evolution of chemistry from high vacuum conditions to reaction conditions.

    PubMed

    Tao, Franklin Feng; Zhang, Shiran; Nguyen, Luan; Zhang, Xueqiang

    2012-12-21

    Bimetallic catalysts are one of the main categories of metal catalysts due to the tunability of electronic and geometric structures through alloying a second metal. The integration of a second metal creates a vast number of possibilities for varying the surface structure and composition of metal catalysts toward designing new catalysts. It is well acknowledged that the surface composition, atomic arrangement, and electronic state of bimetallic catalysts could be different from those before a chemical reaction or catalysis based on ex situ studies. Thanks to advances in electron-based surface analytical techniques, the surface chemistry and structure of bimetallic nanoparticles can be characterized under reaction conditions and during catalysis using ambient pressure analytical techniques including ambient pressure XPS, ambient pressure STM, X-ray absorption spectroscopy and others. These ambient pressure studies revealed various restructurings in the composition and arrangement of atoms in the surface region of catalysts under reaction conditions or during catalysis compared to that before reaction. These restructurings are driven by thermodynamic and kinetic factors. The surface energy of the constituent metals and adsorption energy of reactant molecules or dissociated species on a metal component are two main factors from the point of view of thermodynamics. Correlations between the authentic surface structure and chemistry of catalysts during catalysis and simultaneous catalytic performance were built for understanding catalytic mechanisms of bimetallic catalysts toward designing new catalysts with high activity, selectivity, and durability.

  14. Modeling of Vapor Bubble Growth Under Nucleate Boiling Conditions in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Buyevich, Yu A.; Webbon, Bruce W.

    1995-01-01

    A dynamic model is developed to describe the evolution of a vapor bubble growing at a nucleation site on a superheated surface under arbitrary gravity. The bubble is separated from the surface by a thin microlayer and grows due to the evaporation from the microlayer interface. The average thickness of the microlayer increases as the bubble expands along the surface if the evaporation rate is lower than some critical value. The corresponding threshold value of the surface temperature has to be associated with the burn-out crisis. Two main reasons make for bubble separation, which are the buoyancy force and a force caused by the vapor momentum that comes to the bubble with vapor molecules. The latter force is somewhat diminished if condensation takes place at the upper bubble surface in subcooled liquids. The action of the said forces is opposed by inertia of the additional mass of liquid as the bubble center rises above the surface and by inertia of liquid being expelled by the growing bubble in radial directions. An extra pressure force arises due to the liquid inflow into the microlayer with a finite velocity. The last force helps in holding the bubble close to the surface during an initial stage of bubble evolution. Two limiting regimes with distinctly different properties can be singled out, depending on which of the forces that favor bubble detachment dominates. Under conditions of moderately reduced gravity, the situation is much the same as in normal gravity, although the bubble detachment volume increases as gravity diminishes. In microgravity, the buoyancy force is negligible. Then the bubble is capable of staying near the surface for a long time, with intensive evaporation from the microlayer. It suggests a drastic change in the physical mechanism of heat removal as gravity falls below a certain sufficiently low level. Inferences of the model and conclusions pertaining to effects caused on heat transfer processes by changes in bubble hydrodynamics induced

  15. Modeling of Vapor Bubble Growth Under Nucleate Boiling Conditions in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Buyevich, Yu A.; Webbon, Bruce W.

    1995-01-01

    A dynamic model is developed to describe the evolution of a vapor bubble growing at a nucleation site on a superheated surface under arbitrary gravity. The bubble is separated from the surface by a thin microlayer and grows due to the evaporation from the microlayer interface. The average thickness of the microlayer increases as the bubble expands along the surface if the evaporation rate is lower than some critical value. The corresponding threshold value of the surface temperature has to be associated with the burn-out crisis. Two main reasons make for bubble separation, which are the buoyancy force and a force caused by the vapor momentum that comes to the bubble with vapor molecules. The latter force is somewhat diminished if condensation takes place at the upper bubble surface in subcooled liquids. The action of the said forces is opposed by inertia of the additional mass of liquid as the bubble center rises above the surface and by inertia of liquid being expelled by the growing bubble in radial directions. An extra pressure force arises due to the liquid inflow into the microlayer with a finite velocity. The last force helps in holding the bubble close to the surface during an initial stage of bubble evolution. Two limiting regimes with distinctly different properties can be singled out, depending on which of the forces that favor bubble detachment dominates. Under conditions of moderately reduced gravity, the situation is much the same as in normal gravity, although the bubble detachment volume increases as gravity diminishes. In microgravity, the buoyancy force is negligible. Then the bubble is capable of staying near the surface for a long time, with intensive evaporation from the microlayer. It suggests a drastic change in the physical mechanism of heat removal as gravity falls below a certain sufficiently low level. Inferences of the model and conclusions pertaining to effects caused on heat transfer processes by changes in bubble hydrodynamics induced

  16. The Physical Conditions of Atomic Gas at High Redshift

    NASA Astrophysics Data System (ADS)

    Neeleman, Marcel

    In this thesis we provide insight into the chemical composition, physical conditions and cosmic distribution of atomic gas at high redshift. We study this gas in absorption against bright background quasars in absorption systems known as Damped Ly-alpha Systems (DLAs). These systems contain the bulk of the atomic gas at high redshift and are the likely progenitors of modern-day galaxies. In Chapter 2, we find that the atomic gas in DLAs obeys a mass-metallicity relationship that is similar to the mass-metallicity relationship seen in star-forming galaxies. The evolution of this relationship is linear with redshift, allowing for a planar equation to accurately describe this evolution, which provides a more stringent constraint on simulations modeling DLAs. Furthermore, the concomitant evolution of the mass-metallicity relationship of atomic gas and star-forming galaxies suggests an intimate link between the two. We next use a novel way to measure the physical conditions of the gas by using fine-structure line ratios of singly ionized carbon and silicon. By measuring the density of the upper and lower level states, we are able to determine the temperature, hydrogen density and electron density of the gas. We find that the conditions present in this high redshift gas are consistent with the conditions we see in the local interstellar medium (ISM). A few absorbers have higher than expected pressure, which suggests that they probe the ISM of star-forming galaxies. Finally in Chapter 4, we measure the cosmic neutral hydrogen density at redshifts below 1.6. Below this redshift, the Ly-alpha line of hydrogen is absorbed by the atmosphere, making detection difficult. Using the archive of the Hubble Space Telescope, we compile a comprehensive list of quasars for a search of DLAs at redshift below 1.6. We find that the incidence rate of DLAs and the cosmic neutral hydrogen density is smaller than previously measured, but consistent with the values both locally and at

  17. Thermophysical Properties Measurement of High-Temperature Liquids Under Microgravity Conditions in Controlled Atmospheric Conditions

    NASA Technical Reports Server (NTRS)

    Watanabe, Masahito; Ozawa, Shumpei; Mizuno, Akotoshi; Hibiya, Taketoshi; Kawauchi, Hiroya; Murai, Kentaro; Takahashi, Suguru

    2012-01-01

    Microgravity conditions have advantages of measurement of surface tension and viscosity of metallic liquids by the oscillating drop method with an electromagnetic levitation (EML) device. Thus, we are preparing the experiments of thermophysical properties measurements using the Materials-Science Laboratories ElectroMagnetic-Levitator (MSL-EML) facilities in the international Space station (ISS). Recently, it has been identified that dependence of surface tension on oxygen partial pressure (Po2) must be considered for industrial application of surface tension values. Effect of Po2 on surface tension would apparently change viscosity from the damping oscillation model. Therefore, surface tension and viscosity must be measured simultaneously in the same atmospheric conditions. Moreover, effect of the electromagnetic force (EMF) on the surface oscillations must be clarified to obtain the ideal surface oscillation because the EMF works as the external force on the oscillating liquid droplets, so extensive EMF makes apparently the viscosity values large. In our group, using the parabolic flight levitation experimental facilities (PFLEX) the effect of Po2 and external EMF on surface oscillation of levitated liquid droplets was systematically investigated for the precise measurements of surface tension and viscosity of high temperature liquids for future ISS experiments. We performed the observation of surface oscillations of levitated liquid alloys using PFLEX on board flight experiments by Gulfstream II (G-II) airplane operated by DAS. These observations were performed under the controlled Po2 and also under the suitable EMF conditions. In these experiments, we obtained the density, the viscosity and the surface tension values of liquid Cu. From these results, we discuss about as same as reported data, and also obtained the difference of surface oscillations with the change of the EMF conditions.

  18. 41 CFR 109-43.307-4 - Conditional gifts to reduce the public debt.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Federal Property Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT... heads of field organizations shall take appropriate action as required when conditional gifts are...

  19. High-pressure highly reduced nitrides and oxides from chromitite of a Tibetan ophiolite.

    PubMed

    Dobrzhinetskaya, Larissa F; Wirth, Richard; Yang, Jingsui; Hutcheon, Ian D; Weber, Peter K; Green, Harry W

    2009-11-17

    The deepest rocks known from within Earth are fragments of normal mantle ( approximately 400 km) and metamorphosed sediments ( approximately 350 km), both found exhumed in continental collision terranes. Here, we report fragments of a highly reduced deep mantle environment from at least 300 km, perhaps very much more, extracted from chromite of a Tibetan ophiolite. The sample consists, in part, of diamond, coesite-after-stishovite, the high-pressure form of TiO(2), native iron, high-pressure nitrides with a deep mantle isotopic signature, and associated SiC. This appears to be a natural example of the recently discovered disproportionation of Fe(2+) at very high pressure and consequent low oxygen fugacity (fO(2)) in deep Earth. Encapsulation within chromitite enclosed within upwelling solid mantle rock appears to be the only vehicle capable of transporting these phases and preserving their low-fO(2) environment at the very high temperatures of oceanic spreading centers.

  20. In situ Fe-sulfide coating for arsenic removal under reducing conditions

    NASA Astrophysics Data System (ADS)

    Xie, Xianjun; Liu, Yaqing; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Duan, Mengyu; Wang, Yanxin

    2016-03-01

    An in situ Fe-sulfide coating approach has been developed for As-contaminated groundwater remediation. Alternate injection of Fe(II), O2-free water and S2- can realize Fe-sulfide coating onto quartz sands with minor changes in porosity. As(III) uptake experiment indicated that the retardation factor for As(III) was 37 and dynamic retention capacity was 44.94 mg As(III)/g Fe, which was much higher than the maximum adsorption capacity for As(III) by FeS and FeS2. This result indicated that adsorption cannot be the only mechanism for As(III) uptake by Fe-sulfide coating layer. The SEM image and FTIR spectra results suggested that interaction between As(III) and Fe-sulfides and formation of As-sulfide precipitates could significantly contribute to As(III) uptake by Fe-sulfide coating layer. Alternate injection of Fe(II) + As(III) and S2- was conducted to simulate in situ As immobilization from real groundwater. The SEM image showed that the quartz sands were mainly covered by crystalline framboidal pyrite after such amendment. The breakthrough of As(III) was not observed during this experiment and the removal capacity for As(III) was 109.7 mg As/g Fe. The As(III) immobilization mechanism during alternate injection of Fe(II) + As(III) and S2- was significantly different from that of As(III) uptake by Fe-sulfide coating. The direct interaction between As(III) and S2- produced As-sulfides contributed to the high As(III) removal capacity during alternate injection of Fe(II) + As(III) and S2-. This result indicated that alternate injection of Fe(II) and S2- approach has an attractive application for As-contaminated groundwater remediation under strongly reducing environment.

  1. Conditional Deletion of the Phd2 Gene in Articular Chondrocytes Accelerates Differentiation and Reduces Articular Cartilage Thickness

    PubMed Central

    Cheng, Shaohong; Pourteymoor, Sheila; Alarcon, Catrina; Mohan, Subburaman

    2017-01-01

    Based on our findings that PHD2 is a negative regulator of chondrocyte differentiation and that hypoxia signaling is implicated in the pathogenesis of osteoarthritis, we investigated the consequence of disruption of the Phd2 gene in chondrocytes on the articular cartilage phenotype in mice. Immunohistochemistry detected high expression of PHD2 in the superficial zone (SZ), while PHD3 and HIF-1α (target of PHD2) are mainly expressed in the middle-deep zone (MDZ). Conditional deletion of the Phd2 gene (cKO) in chondrocytes accelerated the transition of progenitors to hypertrophic (differentiating) chondrocytes as revealed by reduced SZ thickness, and increased MDZ thickness, as well as increased chondrocyte hypertrophy. Immunohistochemistry further revealed decreased levels of progenitor markers but increased levels of hypertrophy markers in the articular cartilage of the cKO mice. Treatment of primary articular chondrocytes, in vitro, with IOX2, a specific inhibitor of PHD2, promoted articular chondrocyte differentiation. Knockdown of Hif-1α expression in primary articular chondrocytes using lentiviral vectors containing Hif-1α shRNA resulted in reduced expression levels of Vegf, Glut1, Pgk1, and Col10 compared to control shRNA. We conclude that Phd2 is a key regulator of articular cartilage development that acts by inhibiting the differentiation of articular cartilage progenitors via modulating HIF-1α signaling. PMID:28349987

  2. Role of reduced-intensity conditioning allogeneic hematopoietic cell transplantation in older patients with de novo acute myeloid leukemia.

    PubMed

    Yamasaki, Satoshi; Hirakawa, Akihiro; Aoki, Jun; Uchida, Naoyuki; Fukuda, Takahiro; Ogawa, Hiroyasu; Ohashi, Kazuteru; Kondo, Tadakazu; Eto, Tetsuya; Kanamori, Heiwa; Okumura, Hirokazu; Iwato, Koji; Ichinohe, Tatsuo; Kanda, Junya; Onizuka, Makoto; Kuwatsuka, Yachiyo; Yanada, Masamitsu; Atsuta, Yoshiko; Takami, Akiyoshi; Yano, Shingo

    2017-02-01

    Reduced-intensity conditioning (RIC) regimens extend the therapeutic use of allogeneic hematopoietic cell transplantation (HCT) to older patients. The survival trend in 2325 patients aged >50 years presenting with de novo acute myeloid leukemia (AML) who underwent first reduced-intensity HCT (RIC-HCT) was assessed by retrospectively analyzing outcomes between 2000 and 2013. The annual number of RIC-HCTs in Japan was higher in the 2008-2013 period (n = 205/year [1229/6 years]) than in the 2000-2007 period (n = 137/year [1096/8 years]). Overall and disease-free survival were higher in the 2008-2013 period (P < 0.001) because of the improvement in transplant-related mortality (TRM). Survival regarding RIC-HCT for AML has improved over time, with an increased number of RIC-HCTs in patients with a Karnofsky performance status (KPS) ≥80. However, TRM remains high and the relapse rate has not improved over time. Multivariate analyses showed that a KPS ≥80 and complete remission at HCT were associated with less TRM and relapse, and better survival regardless of age ≥65 years. Accurate timing and prospective identification of patients at risk of TRM may aid the development of risk-adapted strategies for RIC-HCT in AML patients regardless of age.

  3. [The oral cavity condition in patients with high blood pressure].

    PubMed

    Rosiak, Joanna; Kubić-Filiks, Beata; Szymańska, Jolanta

    2015-10-01

    The incidence of high blood pressure in adults is estimated at ca. 30-40% of the general population. Both hypertension disease and hypertensive drugs affect the condition of the patients' oral cavity. A review of the current literature shows that disorders most frequently found in the masticatory organ of patients with hypertension include: xerostomia, changes in salivary glands, gum hypertrophy, lichenoid lesions, taste disorders, and paraesthesias. The authors emphasize that patients with high blood pressure, along with the treatment of the underlying disease, should receive prophylactic and therapeutic dental care. This would enable reduction and/or elimination of unpleasant complaints, and also help prevent the emergence of secondary disorders in the patients' oral cavity as a result of hypertension pharmacotherapy.

  4. Soot formation in diesel combustion under high-EGR conditions.

    SciTech Connect

    Idicheria, Cherian A.; Pickett, Lyle M.

    2005-06-01

    Experiments were conducted in an optically accessible constant-volume combustion vessel to investigate soot formation at diesel combustion conditions - in a high exhaust-gas recirculation (EGR) environment. The ambient oxygen concentration was decreased systematically from 21% to 8% to simulate a wide range of EGR conditions. Quantitative measurements of in-situ soot in quasi-steady n-heptane and No.2 diesel fuel jets were made by using laser extinction and planar laser-induced incandescence (PLII) measurements. Flame lift-off length measurements were also made in support of the soot measurements. At constant ambient temperature, results show that the equivalence ratio estimated at the lift-off length does not vary with the use of EGR, implying an equal amount of fuel-air mixing prior to combustion. Soot measurements show that the soot volume fraction decreases with increasing EGR. The regions of soot formation are effectively 'stretched out' to longer axial and radial distances from the injector with increasing EGR, according to the dilution in ambient oxygen. However, the axial soot distribution and location of maximum soot collapses if plotted in terms of a 'flame coordinate', where the relative fuel-oxygen mixture is equivalent. The total soot in the jet cross-section at the maximum axial soot location initially increases and then decreases to zero as the oxygen concentration decreases from 21% to 8%. The trend is caused by competition between soot formation rates and increasing residence time. Soot formation rates decrease with decreasing oxygen concentration because of the lower combustion temperatures. At the same time, the residence time for soot formation increases, allowing more time for accumulation of soot. Increasing the ambient temperature above nominal diesel engine conditions leads to a rapid increase in soot for high-EGR conditions when compared to conditions with no EGR. This result emphasizes the importance of EGR cooling and its beneficial

  5. Symmetry recovery of cell-free layer after bifurcations of small arterioles in reduced flow conditions: effect of RBC aggregation.

    PubMed

    Ng, Yan Cheng; Namgung, Bumseok; Tien, Sim Leng; Leo, Hwa Liang; Kim, Sangho

    2016-08-01

    Heterogeneous distribution of red blood cells (RBCs) in downstream vessels of arteriolar bifurcations can be promoted by an asymmetric formation of cell-free layer (CFL) in upstream vessels. Consequently, the CFL widths in subsequent downstream vessels become an important determinant for tissue oxygenation (O2) and vascular tone change by varying nitric oxide (NO) availability. To extend our previous understanding on the formation of CFL in arteriolar bifurcations, this study investigated the formation of CFL widths from 2 to 6 vessel-diameter (2D-6D) downstream of arteriolar bifurcations in the rat cremaster muscle (D = 51.5 ± 1.3 μm). As the CFL widths are highly influenced by RBC aggregation, the degree of aggregation was adjusted to simulate levels seen during physiological and pathological states. Our in vivo experimental results showed that the asymmetry of CFL widths persists along downstream vessels up to 6D from the bifurcating point. Moreover, elevated levels of RBC aggregation appeared to retard the recovery of CFL width symmetry. The required length of complete symmetry recovery was estimated to be greater than 11D under reduced flow conditions, which is relatively longer than interbifurcation distances of arterioles for vessel diameter of ∼50 μm. In addition, our numerical prediction showed that the persistent asymmetry of CFL widths could potentially result in a heterogeneous vasoactivity over the entire arteriolar network in such abnormal flow conditions.

  6. Manganese concentration in lobster (Homarus americanus) gills as an index of exposure to reducing conditions in western Long Island Sound

    USGS Publications Warehouse

    Draxler, Andrew F.J.; Sherrell, Robert M.; Wieczorek, Dan; Lavigne, Michele G.; Paulson, A.J.

    2005-01-01

    We examined the accumulation of manganese (Mn) in gill tissues of chemically nai??ve lobsters held in situ at six sites in Long Island Sound (LIS) for up to six weeks to evaluate the possible contribution of eutrophication-driven habitat quality factors to the 1999 mass mortality of American lobsters (Homarus americanus). These western LIS lobster habitats experience seasonal hypoxia, which results in redox-mobilized Mn being transferred to and deposited on the tissues of the lobsters. Manganese accumulated in gill tissue of lobsters throughout the study, but rates were highest at western and southern LIS sites, ranging from 3.4-0.8 ??g/g/d (???16 ??g/g initial). The Baden-Eriksson observation that Mn accumulation in Norway lobsters (Nephrops norvegicus) is associated with ecosystem hypoxia is confirmed and extended to H. americanus. It seems likely that, after accounting for molting frequency, certain critical values may be applied to other lobster habitats of the NE US shelf. If a high proportion of lobsters in autumn have gill Mn concentrations exceeding 30 ??g/g, then the habitats are likely experiencing some reduced oxygen levels. Manganese concentrations above 100 ??g/g suggest exposure to conditions with the potential for lobster mortality should the temperatures of bottom waters become elevated, and gill concentrations above some higher level (perhaps 300 ??g/g) indicate the most severe habitat conditions with a strong potential for hypoxia stress.

  7. Manganese concentration in lobster (Homarus americansus) gills as an index of exposure to reducing conditions in Western Long Island Sound

    USGS Publications Warehouse

    Draxler, Andrew F.J.; Sherrell, Robert M.; Wieczorek, Daniel; Lavigne, Michele G.; Paulson, Anthony J.

    2005-01-01

    We examined the accumulation of manganese (Mn) in gill tissues of chemically naïve lobsters heldin situ at six sites in Long Island Sound (LIS) for up to six weeks to evaluate the possible contribution of eutrophication-driven habitat quality factors to the 1999 mass mortality of American lobsters (Homarus americanus). These western LIS lobster habitats experience seasonal hypoxia, which results in redox-mobilized Mn being transferred to and deposited on the tissues of the lobsters. Manganese accumulated in gill tissue of lobsters throughout the study, but rates were highest at western and southern LIS sites, ranging from 3.4–0.8 μ g/g/d (~16 μg/g initial). The Baden-Eriksson observation that Mn accumulation in Norway lobsters (Nephrops norvegicus) is associated with ecosystem hypoxia is confirmed and extended to H. americanus. It seems likely that, after accounting for molting frequency, certain critical values may be applied to other lobster habitats of the NE US shelf. If a high proportion of lobsters in autumn have gill Mn concentrations exceeding 30 μg/g, then the habitats are likely experiencing some reduced oxygen levels. Manganese concentrations above 100 μg/g suggest exposure to conditions with the potential for lobster mortality should the temperatures of bottom waters become elevated, and gill concentrations above some higher level (perhaps 300 μg/g) indicate the most severe habitat conditions with a strong potential for hypoxia stress.

  8. Fludarabine-based reduced intensity conditioning transplants have a higher incidence of cytomegalovirus reactivation compared with myeloablative transplants.

    PubMed

    George, B; Kerridge, I; Gilroy, N; Huang, G; Hertzberg, M; Gottlieb, D; Bradstock, K

    2010-05-01

    Two hundred and ten adult CMV seropositive patients undergoing myeloablative conditioning (MAC) [n=127] or reduced intensity conditioning (RIC) [n=83] transplants (HCT) were serially monitored for CMV reactivation and disease, using a qualitative polymerase chain reaction (PCR) followed by quantitation with pp65 antigen or quantitative PCR. CMV reactivation occurred in 53 RIC (63.9%) and 61 MAC (48%; P=0.03) transplants at a median of 47 days (range: 24-1977). Risk factors identified included acute GVHD (P=0.001), RIC regimen (P=0.03), unrelated donor (P=0.02), use of anti-thymocyte globulin/alemtuzumb (P=0.02) and use of bone marrow in MAC transplants (P=0.011). On multivariate analysis, RIC transplants and acute GVHD remained independent predictors. Treatment with antiviral drugs resulted in CMV negativity rates of 86.8% in MAC and 88.6% in RIC transplants. CMV disease occurred in 10.8% of RIC and 4.7% of MAC transplants (P=0.15). At a median follow-up of 26 months (range: 3-88), 48.1% of RIC and 50.3% of MAC transplants are alive. The higher incidence of CMV reactivation among RIC transplants suggests the need for novel prophylactic or pre-emptive strategies in this high-risk group of patients.

  9. Aeroacoustic effects of reduced aft tip speed at constant thrust for a model counterrotation turboprop at takeoff conditions

    NASA Technical Reports Server (NTRS)

    Woodward, Richard P.; Hughes, Christopher E.

    1990-01-01

    A model high-speed, advanced counterrotation propeller, F7/A7, was tested in the NASA Lewis Research Center's 9- by 15-foot anechoic wind tunnel at simulated takeoff and approach conditions of Mach 0.2. The propeller was operated in a baseline configuration with the forward and aft rotor blade setting angles (36.2deg and 35.4 deg) and forward and aft rotational speeds essentially equal. Two additional configurations were tested with the aft rotor at increased blade setting angles and the rotational speed reduced to achieve overall performance similar to that of the baseline configuration. The aft rotor blade angles were adjusted such that the thrust and power absorption for each rotor remained the same as for the baseline configuration. Acoustic data were taken with an axially translating microphone probe that was attached to the tunnel floor. Concurrent aerodynamic data were taken to define propeller operating conditions. The aft rotor fundamental tone was about 6 dB lower with the 36.2 deg and 38.4 deg blade setting angles, and about 9 dB lower with the 36.2 and 41.4 deg blade setting angles. Predicted noise reductions based on tip speed considerations were 5 and 9.5 dB, respectively, for the two altered blade setting angles.

  10. Reducing pressure on natural forests through high-yield forestry

    Treesearch

    W.T. Gladstone; F. Thomas Ledig

    1990-01-01

    High-yield forestry can make a valuable contribution to the conservation and sustained use of forest ecosystems. Despite the pressing reasons for conserving forest resources, population growth creates pressures for exploiting them. Unless needs for forest products, export credits, and local employment can be met by new devices, such as high-yield forestry, these...

  11. Anaerobic Naphthalene Degradation by Microbial Pure Cultures under Nitrate-Reducing Conditions

    PubMed Central

    Rockne, Karl J.; Chee-Sanford, Joanne C.; Sanford, Robert A.; Hedlund, Brian P.; Staley, James T.; Strand, Stuart E.

    2000-01-01

    Pure bacterial cultures were isolated from a highly enriched denitrifying consortium previously shown to anaerobically biodegrade naphthalene. The isolates were screened for the ability to grow anaerobically in liquid culture with naphthalene as the sole source of carbon and energy in the presence of nitrate. Three naphthalene-degrading pure cultures were obtained, designated NAP-3-1, NAP-3-2, and NAP-4. Isolate NAP-3-1 tested positive for denitrification using a standard denitrification assay. Neither isolate NAP-3-2 nor isolate NAP-4 produced gas in the assay, but both consumed nitrate and NAP-4 produced significant amounts of nitrite. Isolates NAP-4 and NAP-3-1 transformed 70 to 90% of added naphthalene, and the transformation was nitrate dependent. No significant removal of naphthalene occurred under nitrate-limited conditions or in cell-free controls. Both cultures exhibited partial mineralization of naphthalene, representing 7 to 20% of the initial added 14C-labeled naphthalene. After 57 days of incubation, the largest fraction of the radiolabel in both cultures was recovered in the cell mass (30 to 50%), with minor amounts recovered as unknown soluble metabolites. Nitrate consumption, along with the results from the 14C radiolabel study, are consistent with the oxidation of naphthalene coupled to denitrification for NAP-3-1 and nitrate reduction to nitrite for NAP-4. Phylogenetic analyses based on 16S ribosomal DNA sequences of NAP-3-1 showed that it was closely related to Pseudomonas stutzeri and that NAP-4 was closely related to Vibrio pelagius. This is the first report we know of that demonstrates nitrate-dependent anaerobic degradation and mineralization of naphthalene by pure cultures. PMID:10742247

  12. Classical conditioning analog enhanced acetylcholine responses but reduced excitability of an identified neuron.

    PubMed

    Lorenzetti, Fred D; Baxter, Douglas A; Byrne, John H

    2011-10-12

    Although classical and operant conditioning are operationally distinct, it is unclear whether these two forms of learning are mechanistically distinct or similar. Feeding behavior of Aplysia provides a useful model system for addressing this issue. Both classical and operant appetitive behavioral training enhance feeding, and neuronal correlates have been identified. Behavioral training was replicated by in vitro analogs that use isolated ganglia. Moreover, a single-cell analog of operant conditioning was developed using neuron B51, a cell important for the expression of the conditioned behavior. Here, a single-cell analog of classical conditioning was developed. Acetylcholine (ACh) mediated the conditioned stimulus (CS)-elicited excitation of B51 in ganglia and mimicked the CS in the single-cell analog of classical conditioning. Pairing ACh with dopamine, which mediates the unconditioned stimulus in ganglia, decreased the excitability of B51, and increased the CS-elicited excitation of B51, similar to results following both in vivo and in vitro classical training. Finally, a D1 dopamine receptor (D1R) agonist failed to support classical conditioning in the cellular analog, whereas D1R mediates reinforcement in operant conditioning.

  13. Amphetamine Conditioned Place Preference in High and Low Impulsive Rats

    PubMed Central

    Yates, Justin R.; Marusich, Julie A.; Gipson, Cassandra D.; Beckmann, Joshua S.; Bardo, Michael T.

    2011-01-01

    Stimulants such as d-amphetamine (AMPH) are used commonly to treat attention-deficit hyperactivity disorder (ADHD), but concerns have been raised regarding the use of AMPH due to its reinforcing and potentially addictive properties. The current study examined if individual differences in impulsive choice predict AMPH-induced hyperactivity and conditioned place preference (CPP). Rats were first tested in delay discounting using an adjusting delay procedure to measure impulsive choice and then were subsequently tested for AMPH CPP. High impulsive (HiI) and low impulsive (LoI) rats were conditioned across four sessions with 0.1, 0.5, or 1.5 mg/kg of AMPH. AMPH increased locomotor activity for HiI and LoI rats following 0.5 mg/kg but failed to increase activity following 0.1 and 1.5 mg/kg. CPP was established for HiI rats with both 0.5 and 1.5 mg/kg of AMPH, whereas LoI rats did not develop CPP following any dose of AMPH; HiI and LoI groups differed significantly following 0.5 mg/kg of AMPH. These results indicate that HiI rats are more sensitive to the rewarding effects of AMPH compared to LoI rats, which is consistent with research showing that high impulsive individuals may be more vulnerable to stimulant abuse. PMID:21807020

  14. Lie construction affects information storage under high memory load condition.

    PubMed

    Liu, Yuqiu; Wang, Chunjie; Jiang, Haibo; He, Hongjian; Chen, Feiyan

    2017-01-01

    Previous studies indicate that lying consumes cognitive resources, especially working memory (WM) resources. Considering the dual functions that WM might play in lying: holding the truth-related information and turning the truth into lies, the present study examined the relationship between the information storage and processing in the lie construction. To achieve that goal, a deception task based on the old/new recognition paradigm was designed, which could manipulate two levels of WM load (low-load task using 4 items and high-load task using 6 items) during the deception process. The analyses based on the amplitude of the contralateral delay activity (CDA), a proved index of the number of representations being held in WM, showed that the CDA amplitude was lower in the deception process than that in the truth telling process under the high-load condition. In contrast, under the low-load condition, no CDA difference was found between the deception and truth telling processes. Therefore, we deduced that the lie construction and information storage compete for WM resources; when the available WM resources cannot meet this cognitive demand, the WM resources occupied by the information storage would be consumed by the lie construction.

  15. High motility reduces grazing mortality of planktonic bacteria.

    PubMed

    Matz, Carsten; Jürgens, Klaus

    2005-02-01

    We tested the impact of bacterial swimming speed on the survival of planktonic bacteria in the presence of protozoan grazers. Grazing experiments with three common bacterivorous nanoflagellates revealed low clearance rates for highly motile bacteria. High-resolution video microscopy demonstrated that the number of predator-prey contacts increased with bacterial swimming speed, but ingestion rates dropped at speeds of >25 microm s(-1) as a result of handling problems with highly motile cells. Comparative studies of a moderately motile strain (<25 microm s(-1)) and a highly motile strain (>45 microm s(-1)) further revealed changes in the bacterial swimming speed distribution due to speed-selective flagellate grazing. Better long-term survival of the highly motile strain was indicated by fourfold-higher bacterial numbers in the presence of grazing compared to the moderately motile strain. Putative constraints of maintaining high swimming speeds were tested at high growth rates and under starvation with the following results: (i) for two out of three strains increased growth rate resulted in larger and slower bacterial cells, and (ii) starved cells became smaller but maintained their swimming speeds. Combined data sets for bacterial swimming speed and cell size revealed highest grazing losses for moderately motile bacteria with a cell size between 0.2 and 0.4 microm(3). Grazing mortality was lowest for cells of >0.5 microm(3) and small, highly motile bacteria. Survival efficiencies of >95% for the ultramicrobacterial isolate CP-1 (< or =0.1 microm(3), >50 microm s(-1)) illustrated the combined protective action of small cell size and high motility. Our findings suggest that motility has an important adaptive function in the survival of planktonic bacteria during protozoan grazing.

  16. Obesity as a Conditioning Factor for High-Altitude Diseases.

    PubMed

    San Martin, Rocío; Brito, Julio; Siques, Patricia; León-Velarde, Fabiola

    2017-01-01

    Obesity, a worldwide epidemic, has become a major health burden because it is usually accompanied by an increased risk for insulin resistance, diabetes, hypertension, cardiovascular diseases, and even some kinds of cancer. It also results in associated increases in healthcare expenditures and labor and economic consequences. There are also other fields of medicine and biology where obesity or being overweight play a major role, such as high-altitude illnesses (acute mountain sickness, hypoxic pulmonary hypertension, and chronic mountain sickness), where an increasing relationship among these two morbid statuses has been demonstrated. This association could be rooted in the interactions between obesity-related metabolic alterations and critical ventilation impairments due to obesity, which would aggravate hypobaric hypoxia at high altitudes, leading to hypoxemia, which is a trigger for developing high-altitude diseases. This review examines the current literature to support the idea that obesity or overweight could be major conditioning factors at high altitude. © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

  17. (-)-Bornyl acetate induces autonomic relaxation and reduces arousal level after visual display terminal work without any influences of task performance in low-dose condition.

    PubMed

    Matsubara, Eri; Fukagawa, Mio; Okamoto, Tsuyoshi; Ohnuki, Koichiro; Shimizu, Kuniyoshi; Kondo, Ryuichiro

    2011-04-01

    (-)-Bornyl acetate is the main volatile constituent in numerous conifer oils and has a camphoraceous, pine-needle-like odor. It is frequently used as the conifer needle composition in soap, bath products, room sprays, and pharmaceutical products. However, the psychophysiological effects of (-)-bornyl acetate remained unclear. We investigated the effects of breathing air mixed with (-)-bornyl acetate at different doses (low-dose and high-dose conditions) on the individuals during and after VDT (visual display terminal) work using a visual discrimination task. The amounts of (-)-bornyl acetate through our odorant delivery system for 40 min were 279.4 µg in the low-dose and 716.3 µg in the high-dose (-)-bornyl acetate condition. (-)-Bornyl acetate induced changes of autonomic nervous system for relaxation and reduced arousal level after VDT work without any influences of task performance in low-dose condition, but not in high-dose condition.

  18. Reduced amygdala responsivity during conditioning to trauma-related stimuli in posttraumatic stress disorder.

    PubMed

    Diener, Slawomira J; Nees, Frauke; Wessa, Michèle; Wirtz, Gustav; Frommberger, Ulrich; Penga, Tina; Ruttorf, Michaela; Ruf, Matthias; Schmahl, Christian; Flor, Herta

    2016-10-01

    Exaggerated conditioned fear responses and impaired extinction along with amygdala overactivation have been observed in posttraumatic stress disorder (PTSD). These fear responses might be triggered by cues related to the trauma through higher-order conditioning, where reminders of the trauma may serve as unconditioned stimuli (US) and could maintain the fear response. We compared arousal, valence, and US expectancy ratings and BOLD brain responses using fMRI in 14 traumatized persons with PTSD and 14 without PTSD (NPTSD) and 13 matched healthy controls (HC) in a differential aversive conditioning paradigm. The US were trauma-specific pictures for the PTSD and NPTSD group and equally aversive and arousing for the HC; the conditioned stimuli (CS) were graphic displays. During conditioning, the PTSD patients compared to the NPTSD and HC indicated higher arousal to the conditioned stimulus that was paired with the trauma picture (CS+) compared to the unpaired (CS-), increased dissociation during acquisition and extinction, and failure to extinguish the CS/US-association compared to NPTSD. During early and late acquisition, the PTSD patients showed a significantly lower amygdala activation to CS+ versus CS- and a negative interaction between activation in the amygdala and dorsolateral prefrontal cortex (PFC), while NPTSD and HC displayed a negative interaction between amygdala and medial PFC. These findings suggest maladaptive anticipatory coping with trauma-related stimuli in patients with PTSD, indicated by enhanced conditioning, with related abnormal amygdala reactivity and connectivity, and delayed extinction.

  19. Highly reflective roof surfaces reduce cooling energy use and peak demand

    SciTech Connect

    George, K.L.

    1993-12-31

    Light-colored building surfaces are a time-honored method of staying cool, familiar to anyone who has seen the white-washed buildings in the Mediterranean, the Caribbean, and other warm climes. This heat rejecting strategy has been largely ignored in many places since the advent of mechanical air conditioning. However, recent monitoring experiments suggest that utilities could reduce summer cooling loads significantly by encouraging wide-scale application of light-colored, highly reflective roof surfaces on homes and small commercial buildings. Recent field tests in California and Florida show that application of light-colored coatings to poorly insulated roof systems can reduce cooling energy use and peak demand by more than one-third. Installation of highly reflective, or high ``albedo,`` roofs can be a cost-effective and low-risk utility DSM measure if done during new construction or when buildings are scheduled for reroofing. Most commercial building roofing materials are available in white versions or are easily coated. The residential market is more problematic, however, since asphalt shingles, which constitute more than half of the US residential roofing market, are not highly reflective. More research and market development is warranted to help realize the potential of highly reflective roofs. This includes additional product testing, labeling of highly reflective roofing materials, development of nonwhite reflective surfaces, additional performance monitoring, and implementation of utility pilot programs.

  20. Effects of stigma-reducing conditions on intention to seek psychological help among Korean college students with anxious-ambivalent attachment.

    PubMed

    Nam, Suk Kyung; Choi, Seong In; Lee, Sang Min

    2015-05-01

    This study aimed to examine whether stigma-reducing conditions (i.e., random assignment of participants to hypothetical scenarios with varying levels of stigma) effectively increase intention to seek help for Korean college students with anxious-ambivalent attachment style, depending on previous counseling experience. Three hundred thirty Korean college students participated and were randomly assigned to either a low or a high stigma-reducing manipulative condition group. Each group was provided with three possible strategies to reduce stigma: the location of a counseling center, contact with a mental health patient, and the media portrayal of mental illness. In the high-stigma group, the strategies were described in a way that was highly stigmatizing. In the other group, the 3 strategies were created in a way that was not as stigmatizing. In order to examine the effect of stigma-reducing scenarios through the conditions, participants were also instructed to remember a previous or current stressful situation before responding to the questionnaire. The results of multivariate analysis of variance showed a 3-way interaction effect (i.e., level of stigma based on stigma manipulative condition, level of attachment anxiety, and previous counseling experience) on the intentions score when the "contact" and the "media" strategies were applied. The results indicated that individuals who have a higher level of attachment anxiety and a previous experience of counseling were more sensitive to the stigma-reducing manipulative condition. These results highlight the importance of the "contact" and "media" strategies in reducing stigma of seeking counseling for mental health services. (c) 2015 APA, all rights reserved).

  1. High Temperature Thermosetting Polyimide Nanocomposites Prepared with Reduced Charge Organoclay

    NASA Technical Reports Server (NTRS)

    Campbell, Sandi; Liang, Margaret I.

    2005-01-01

    The naturally occurring sodium and calcium cations found in bentonite clay galleries were exchanged with lithium cations. Following the cation exchange, a series of reduced charge clays were prepared by heat treatment of the lithium bentonite at 130 C, 150 C, or 170 C. Inductively coupled plasma (ICP) analysis showed that heating the lithium clay at elevated temperatures reduced its cation exchange capacity. Ion exchange of heat-treated clays with either a protonated alkyl amine or a protonated aromatic diamine resulted in decreasing amounts of the organic modifier incorporated into the lithium clay. The level of silicate dispersion in a thermosetting polyimide matrix was dependent upon the temperature of Li-clay heat treatment as well as the organic modification. In general, clays treated at 150 C or 170 C, and exchanged with protonated octadcylamine or protonated 2,2'-dimethlybenzidine (DMBZ) showed a higher degree of dispersion than clays treated at 130 C, or exchanged with protonated dodecylamine. Dynamic mechanical analysis showed little change in the storage modulus or T(sub g) of the nanocomposites compared to the base resin. However, long term isothermal aging of the samples showed a significant decrease in the resin oxidative weight loss. Nanocomposite samples aged in air for 1000 hours at 288 C showed of to a decrease in weight loss compared to that of the base resin. This again was dependent on the temperature at which the Li-clay was heated and the choice of organic modification.

  2. Reduced discomfort during high-definition transcutaneous stimulation using 6% benzocaine.

    PubMed

    Guleyupoglu, Berkan; Febles, Nicole; Minhas, Preet; Hahn, Christoph; Bikson, Marom

    2014-01-01

    High-Definition transcranial Direct Current Stimulation (HD-tDCS) allows for non-invasive neuromodulation using an array of compact (approximately 1 cm(2) contact area) "High-Definition" (HD) electrodes, as compared to conventional tDCS (which uses two large pads that are approximately 35 cm(2)). In a previous transcutaneous study, we developed and validated designs for HD electrodes that reduce discomfort over >20 min session with 2 mA electrode current. The purpose of this study was to investigate the use of a chemical pretreatment with 6% benzocaine (topical numbing agent) to further reduce subjective discomfort during transcutaneous stimulation and to allow for better sham controlled studies. Pre-treatment with 6% benzocaine was compared with control (no pretreatment) for 22 min 2 mA of stimulation, with either CCNY-4 or Lectron II electroconductive gel, for both cathodal and anodal transcutaneous (forearm) stimulation (eight different combinations). RESULTS show that for all conditions and polarities tested, stimulation with HD electrodes is safe and well tolerated and that pretreatment further reduced subjective discomfort. Pretreatment with a mild analgesic reduces discomfort during HD-tDCS.

  3. Development of High Speed Inverter Rotary Compressor for the Air-conditioning System

    NASA Astrophysics Data System (ADS)

    Kang, Seoung-Min; Yang, Eun-soo; Shin, Jin-Ung; Park, Joon-Hong; Lee, Se-Dong; Ha, Jong-Hun; Son, Young-Boo; Lee, Byeong-Chul

    2015-08-01

    In order to meet the various operating loads of an air-conditioning system, an inverter compressor with a wide operational range is necessary. One of the ways to achieve a wide operation range is to drive a small capacity compressor at high speed. Moreover, it is possible to maximize the efficiency in part-load operation condition close to actual operating conditions and to reduce the cost by compact design of a small capacity compressor. In addition, the shortage of maximum capacity, due to the small rated capacity, is covered through high speed operation. However, in general, if the compressor operates at high speed, problems occurs such as reduced efficiency due to friction, increased noise, increased amount of oil discharge and decreased durability of the main components. In order to solve these problems the following have been investigated: optimized dimension parameters of the compression chamber, enhanced shaft design and the structure for the reduction of oil discharge and noise at high speed operation. Finally the high speed inverter rotary compressor with high efficiency and more compact size has been developed as compared with the conventional rotary compressor.

  4. In situ Fe-sulfide coating for arsenic removal under reducing conditions

    SciTech Connect

    Xie, Xianjun; Liu, Yaqing; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Duan, Mengyu; Wang, Yanxin

    2016-03-01

    An in situ Fe-sulfide coating approach has been developed for As-contaminated groundwater remediation. Alternate injection of Fe(II), O2-free water and S2$-$ can realize Fe-sulfide coating onto quartz sands with minor changes in porosity. As(III) uptake experiment indicated that the retardation factor for As(III) was 37 and dynamic retention capacity was 44.94 mg As(III)/g Fe, which was much higher than the maximum adsorption capacity for As(III) by FeS and FeS2. This result indicated that adsorption cannot be the only mechanism for As(III) uptake by Fe-sulfide coating layer. The SEM image and FTIR spectra results suggested that interaction between As(III) and Fe-sulfides and formation of As-sulfide precipitates could significantly contribute to As(III) uptake by Fe-sulfide coating layer. Alternate injection of Fe(II) + As(III) and S2$-$ was conducted to simulate in situ As immobilization from real groundwater. The SEM image showed that the quartz sands were mainly covered by crystalline framboidal pyrite after such amendment. The breakthrough of As(III) was not observed during this experiment and the removal capacity for As(III) was 109.7 mg As/g Fe. The As(III) immobilization mechanism during alternate injection of Fe(II) + As(III) and S2$-$ was significantly different from that of As(III) uptake by Fe-sulfide coating. The direct interaction between As(III) and S2$-$ produced As-sulfides contributed to the high As(III) removal capacity during alternate injection of Fe(II) + As(III) and S2$-$. This result indicated that alternate injection of Fe(II) and S2$-$ approach has an attractive application for As-contaminated groundwater remediation under strongly reducing environment.

  5. Noninvasive health condition monitoring device for workers at high altitudes conditions.

    PubMed

    Aqueveque, Pablo; Gutierrez, Cristopher; Saavedra, Francisco; Pino, Esteban J

    2016-08-01

    This work presents the design and implementation of a continuous monitoring device to control the health state of workers, for instance miners, at high altitudes. The extreme ambient conditions are harmful for peoples' health; therefore a continuous control of the workers' vital signs is necessary. The developed system includes physiological variables: electrocardiogram (ECG), respiratory activity and body temperature (BT), and ambient variables: ambient temperature (AT) and relative humidity (RH). The noninvasive sensors are incorporated in a t-shirt to deliver a functional device, and maximum comfort to the users. The device is able to continuously calculate heart rate (HR) and respiration rate (RR), and establish a wireless data transmission to a central monitoring station.

  6. High-performance mussel-inspired adhesives of reduced complexity

    NASA Astrophysics Data System (ADS)

    Ahn, B. Kollbe; Das, Saurabh; Linstadt, Roscoe; Kaufman, Yair; Martinez-Rodriguez, Nadine R.; Mirshafian, Razieh; Kesselman, Ellina; Talmon, Yeshayahu; Lipshutz, Bruce H.; Israelachvili, Jacob N.; Waite, J. Herbert

    2015-10-01

    Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (~50 mJ m-2) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (<4 nm) and strong glue layer. The catecholic zwitterion holds particular promise as an adhesive for nanofabrication. This study significantly simplifies bio-inspired themes for wet adhesion by combining catechol with hydrophobic and electrostatic functional groups in a small molecule.

  7. High-performance mussel-inspired adhesives of reduced complexity

    PubMed Central

    Ahn, B. Kollbe; Das, Saurabh; Linstadt, Roscoe; Kaufman, Yair; Martinez-Rodriguez, Nadine R.; Mirshafian, Razieh; Kesselman, Ellina; Talmon, Yeshayahu; Lipshutz, Bruce H.; Israelachvili, Jacob N.; Waite, J. Herbert

    2015-01-01

    Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (∼50 mJ m−2) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (<4 nm) and strong glue layer. The catecholic zwitterion holds particular promise as an adhesive for nanofabrication. This study significantly simplifies bio-inspired themes for wet adhesion by combining catechol with hydrophobic and electrostatic functional groups in a small molecule. PMID:26478273

  8. High-speed floating-point divider with reduced area

    NASA Astrophysics Data System (ADS)

    Han, Kyung-Nam; Tenca, Alexandre F.; Tran, David

    2009-08-01

    This paper presents a new implementation of a floating-point divider unit with a competitive performance and reduced area based on proposed modifications to the recursive equations of Goldschmidt algorithm. The Goldschmidt algorithm takes advantage of parallelism in the Newton-Raphson method with the same quadratic convergence. However, recursive equations in the Goldschmidt algorithm consist of a series of multiplications with full-precision operands, and it suffers from large area consumption. In this paper, the recursive equations in the algorithm are modified to replace full-precision multipliers with smaller multipliers and squarers. Implementations of floating-point reciprocal and divider using the modification are presented. Synthesis result shows around 20% to 40% area reduction when it is compared to the implementation based on the conventional Goldschmidt algorithm.

  9. High-performance mussel-inspired adhesives of reduced complexity.

    PubMed

    Ahn, B Kollbe; Das, Saurabh; Linstadt, Roscoe; Kaufman, Yair; Martinez-Rodriguez, Nadine R; Mirshafian, Razieh; Kesselman, Ellina; Talmon, Yeshayahu; Lipshutz, Bruce H; Israelachvili, Jacob N; Waite, J Herbert

    2015-10-19

    Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (∼50 mJ m(-2)) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (<4 nm) and strong glue layer. The catecholic zwitterion holds particular promise as an adhesive for nanofabrication. This study significantly simplifies bio-inspired themes for wet adhesion by combining catechol with hydrophobic and electrostatic functional groups in a small molecule.

  10. Slow waves moving near the openings in highly stressed conditions

    NASA Astrophysics Data System (ADS)

    Guzev, Michail; Makarov, Vladimir

    2017-04-01

    In situ experiments have shown the unusual deformation waves near the openings on high depth of the construction. Process of the wave spreading is beginning after the mining and has two stages of the zonal mesocracking structure formation and development [1]. Extending in a radial direction, the wave poorly fades with distance. For phenomenon modelling the theoretical decision for non-Eucledian models about opening of round cross-section in strongly compressed rock massif is used [2]. The decision qualitatively repeats behaviour of a wave in a rock mass, adjustment of phenomenological parametres is executed. References [1] Vladimir V. Makarov, Mikhail A. Guzev, Vladimir N. Odintsev, Lyudmila S. Ksendzenko (2016) Periodical zonal character of damage near the openings in highly-stressed rock mass conditions. Journal of Rock Mechanics and Geotechnical Engineering. Volume 8, Issue 2, pp. 164-169. [2] M.A. Guzev, V.V. Makarov, 2007. Deforming and failure of the high stressed rocks around the openings, RAS Edit., Vladivostok, 2007, P. 232 (in Russian).

  11. Reducing the High School Dropout Rate. KIDS COUNT Indicator Brief

    ERIC Educational Resources Information Center

    Shore, Rima; Shore, Barbara

    2009-01-01

    Researchers use many different methods to calculate the high school dropout rate, and depending on the approach, the numbers can look very different. But, no matter which method is used, the key finding is the same: too many students are leaving school without the knowledge and skills they need to meet the demands of twenty-first century…

  12. Teacher Initiatives to Reduce Truancy among High School Students

    ERIC Educational Resources Information Center

    Nemec, Christopher J.; Watson, Rod A.

    2007-01-01

    The purpose of this research project was to improve the attendance of high school students using teacher initiatives. There were two teachers and about 140 students involved. The interventions used were improving lesson plans, developing better relationships with students and positive incentives. The students at this school had a history of very…

  13. Using Infant Simulation to Reduce Pregnancy among High School Students

    ERIC Educational Resources Information Center

    McCowan, Richard J.; Roberts, Scott W.; Slaughter, John

    2009-01-01

    A long-term public health goal in the United States involves convincing adolescents to postpone sexual activity or promote responsible sexual activity. This study investigated the effect of using infant simulators on sexuality, child care attitudes and knowledge with a sample of 309 high school students from seven different states. The treatment…

  14. Reducing High Absenteeism through Low-Cost Incentives.

    ERIC Educational Resources Information Center

    North Chaplik, Barbara D.; Engel, Ross A.

    1984-01-01

    Describes a study of the effects of a low-cost incentive program--including daily, weekly, and monthly reinforcements such as attention, approval, and inexpensive awards--on the absenteeism of high-absence employees in an urban school district's transportation department. A 20-percent reduction in absenteeism was achieved. (TE)

  15. Bubble Stripping as a Tool to Reduce High Dissolved CO2 in Coastal Marine Ecosystems

    NASA Astrophysics Data System (ADS)

    Koweek, D.; Mucciarone, D. A.; Dunbar, R. B.

    2016-02-01

    High dissolved CO2 concentrations in coastal ecosystems are a common occurrence due to a combination of large ecosystem metabolism and long residence times. Many of the socially, commercially, and recreationally important species may have adapted to this natural variability over time. However, eutrophication and ocean acidification may be perturbing the water chemistry beyond the bounds of tolerance for these organisms. We are currently limited in our ability to deal with the geochemical changes unfolding in our coastal ocean. This study helps to address this deficit of solutions by introducing bubble stripping as a novel geochemical engineering approach to reducing high CO2 in coastal marine ecosystems. We use an empirically validated numerical model to find that air/sea gas exchange rates within a bubbled system are 1-2 orders of magnitude higher than within a non-bubbled system. By coupling bubbling-enhanced ventilation to a coastal ecosystem metabolism model, we demonstrate that strategically timed bubble plumes can mitigate exposure to high CO2 under present-day conditions and that exposure mitigation is enhanced in the more acidic conditions predicted by the end of the century. The Fifth Assessment Report of the Intergovernmental Panel on Climate Change emphasizes the need to both adapt to and mitigate the effects of climate change and ocean acidification. We believe shallow water bubble stripping could be one approach for reducing high CO2 conditions in coastal ecosystems and should be added to the growing list of engineering approaches intended to increase coastal resilience in a changing ocean.

  16. Isolation of new aureobasidium strains that produce high-molecular-weight pullulan with reduced pigmentation.

    PubMed

    Pollock, T J; Thorne, L; Armentrout, R W

    1992-03-01

    New isolates of Aureobasidium pullulans were obtained from plant leaf surfaces gathered in San Diego County. The new fungal isolates were identified as A. pullulans on the basis of the appearance of polymorphic colonies formed on agar plates, the electrophoretic profiles of repeated genomic DNA sequences, and the production of pullulan in shake flask cultures. The isolates showed different degrees of pigmentation. One of the natural isolates was nonpigmented under mock production conditions in liquid culture, but was still able to synthesize a reduced amount of pigment on agar plates at late times. A mutagenic treatment with ethidium bromide produced derivatives of normally pigmented natural isolates that exhibited an increased tendency toward yeastlike growth and reduced pigmentation. Additionally, some of the new isolates and mutant derivatives accumulated pullulan of relatively high molecular weight in the culture broths.

  17. Isolation of New Aureobasidium Strains That Produce High-Molecular-Weight Pullulan with Reduced Pigmentation

    PubMed Central

    Pollock, Thomas J.; Thorne, Linda; Armentrout, Richard W.

    1992-01-01

    New isolates of Aureobasidium pullulans were obtained from plant leaf surfaces gathered in San Diego County. The new fungal isolates were identified as A. pullulans on the basis of the appearance of polymorphic colonies formed on agar plates, the electrophoretic profiles of repeated genomic DNA sequences, and the production of pullulan in shake flask cultures. The isolates showed different degrees of pigmentation. One of the natural isolates was nonpigmented under mock production conditions in liquid culture, but was still able to synthesize a reduced amount of pigment on agar plates at late times. A mutagenic treatment with ethidium bromide produced derivatives of normally pigmented natural isolates that exhibited an increased tendency toward yeastlike growth and reduced pigmentation. Additionally, some of the new isolates and mutant derivatives accumulated pullulan of relatively high molecular weight in the culture broths. Images PMID:16348676

  18. Environmental conditions for alternative tree cover states in high latitudes

    NASA Astrophysics Data System (ADS)

    Abis, Beniamino; Brovkin, Victor

    2016-04-01

    Previous analysis of the vegetation cover from remote sensing revealed the existence of three alternative modes in the frequency distribution of boreal tree cover: a sparsely vegetated treeless state, a savanna-like state, and a forest state. Identifying which are the regions subject to multimodality, and assessing which are the main factors underlying their existence, is important to project future change of natural vegetation cover and its effect on climate. We study the impact on the forest cover fraction distribution of seven globally-observed environmental factors: mean annual rainfall, mean minimum temperature, growing degree days above 0, permafrost distribution, soil moisture, wildfire occurrence frequency, and thawing depth. Through the use of generalised additive models, regression trees, and conditional histograms, we find that the main factors determining the forest distribution in high latitudes are: permafrost distribution, mean annual rainfall, mean minimum temperature, soil moisture, and wildfire frequency. Additionally, we find differences between regions within the boreal area, such as Eurasia, Eastern North America, and Western North America. Furthermore, using a classification based on these factors, we show the existence and location of alternative tree cover states under the same climate conditions in the boreal region. These are areas of potential interest for a more detailed analysis of land-atmosphere interactions.

  19. Reduced cannibalistic behavior of African catfish, Clarias gariepinus, larvae under dark and dim conditions.

    PubMed

    Mukai, Yukinori; Sanudin, Noorsyarinah; Firdaus, Rian Freddie; Saad, Shahbudin

    2013-06-01

    In general, African catfish shows higher survival rates in the dark conditions than in the light conditions. In this study, larval behavior of African catfish was observed under 0, 0.01, 0.1, 1, 10, and 100 lx using a CCD camera to investigate the reason why African catfish larvae show higher survival rates in dark conditions. The larvae showed significantly higher swimming activity under 0, 0.01, and 0.1 lx than that under 10 and 100 lx. The larvae also showed significantly increased aggressive behavior under 10 and 100 lx; the swimming larvae attacked resting individuals more frequently under 10 and 100 lx than under 0, 0.01, and 0.1 lx. The aggressive behavior and sharp teeth of the attacking larvae appeared to induce skin surface lesions on injured larvae. Chemical substances were then generated from the injured skin surface, and these chemical stimuli triggered cannibalistic behavior in other fish near the injured fish. The results of this study demonstrate that the higher survival rates of African catfish larvae under dark conditions are a result of inactivity and subsequent increase in chemical releasing stimuli concentrations around inactive individuals that triggers feeding behavior in nearby active catfish. Therefore, we recommend larval rearing of African catfish in dark or dim conditions, as it improves catfish survival rates.

  20. Optimal conditions for tissue perforation using high intensity focused ultrasound

    NASA Astrophysics Data System (ADS)

    Mochizuki, Takashi; Kihara, Taizo; Ogawa, Kouji; Tanabe, Ryoko; Yosizawa, Shin; Umemura, Shin-ichiro; Kakimoto, Takashi; Yamashita, Hiromasa; Chiba, Toshio

    2012-10-01

    To perforate tissue lying deep part in body, a large size transducer was assembled by combining four spherical-shaped transducers, and the optimal conditions for tissue perforation have studied using ventricle muscle of chicken as a target. The ex vivo experiments showed that ventricle muscle was successfully perforated both when it was exposed to High Intensity Focused Ultrasound (HIFU) directly and when it was exposed to HIFU through atrial muscle layer. Moreover, it was shown that calculated acoustic power distributions are well similar to the perforation patterns, and that the acoustic energy distributes very complexly near the focus. Lastly, perforation on the living rabbit bladder wall was demonstrated as a preliminary in vivo experiment.

  1. Speciation and Fate of Trace Metals in Estuarine Sediments Under Reduced and Oxidized Conditions, Seaplane Lagoon, Alameda Naval Air Station

    SciTech Connect

    Carroll, S A; Day, P A; Esser, B; Randall, S

    2002-10-18

    We have identified important chemical reactions that control the fate of metal-contaminated estuarine sediments if they are left undisturbed (in situ) or if they are dredged. We combined information on the molecular bonding of metals in solids from X-ray absorption spectroscopy (XAS) with thermodynamic and kinetic driving forces obtained from dissolved metal concentrations to deduce the dominant reactions under reduced and oxidized conditions. We evaluated the in situ geochemistry of metals (cadmium, chromium, iron, lead, manganese and zinc) as a function of sediment depth (to 100 cm) from a 60-year record of contamination at the Alameda Naval Air Station, California. Results from XAS and thermodynamic modeling of porewaters show that cadmium and most of the zinc form stable sulfide phases, and that lead and chromium are associated with stable carbonate, phosphate, phyllosilicate, or oxide minerals. Therefore, there is minimal risk associated with the release of these trace metals from the deeper sediments contaminated prior to the Clean Water Act (1975) as long as reducing conditions are maintained. Increased concentrations of dissolved metals with depth were indicative of the formation of metal HS- complexes. The sediments also contain zinc, chromium, and manganese associated with detrital iron-rich phyllosilicates and/or oxides. These phases are recalcitrant at near-neutral pH and do not undergo reductive dissolution within the 60-year depositional history of sediments at this site. The fate of these metals during dredging was evaluated by comparing in situ geochemistry with that of sediments oxidized by seawater in laboratory experiments. Cadmium and zinc pose the greatest hazard from dredging because their sulfides were highly reactive in seawater. However, their dissolved concentrations under oxic conditions were limited eventually by sorption to or co-precipitation with an iron (oxy)hydroxide. About 50% of the reacted CdS and 80% of the reacted ZnS were

  2. PROBING THE PHYSICAL CONDITIONS OF ATOMIC GAS AT HIGH REDSHIFT

    SciTech Connect

    Neeleman, Marcel; Wolfe, Arthur M.; Prochaska, J. Xavier

    2015-02-10

    A new method is used to measure the physical conditions of the gas in damped Lyα systems (DLAs). Using high-resolution absorption spectra of a sample of 80 DLAs, we are able to measure the ratio of the upper and lower fine-structure levels of the ground state of C{sup +} and Si{sup +}. These ratios are determined solely by the physical conditions of the gas. We explore the allowed physical parameter space using a Monte Carlo Markov chain method to constrain simultaneously the temperature, neutral hydrogen density, and electron density of each DLA. The results indicate that at least 5% of all DLAs have the bulk of their gas in a dense, cold phase with typical densities of ∼100 cm{sup –3} and temperatures below 500 K. We further find that the typical pressure of DLAs in our sample is log (P/k{sub B} ) = 3.4 (K cm{sup –3}), which is comparable to the pressure of the local interstellar medium (ISM), and that the components containing the bulk of the neutral gas can be quite small with absorption sizes as small as a few parsecs. We show that the majority of the systems are consistent with having densities significantly higher than expected for a purely canonical warm neutral medium, indicating that significant quantities of dense gas (i.e., n {sub H} > 0.1 cm{sup –3}) are required to match observations. Finally, we identify eight systems with positive detections of Si II*. These systems have pressures (P/k{sub B} ) in excess of 20,000 K cm{sup –3}, which suggest that these systems tag a highly turbulent ISM in young, star-forming galaxies.

  3. High order optimal control of space trajectories with uncertain boundary conditions

    NASA Astrophysics Data System (ADS)

    Di Lizia, P.; Armellin, R.; Bernelli-Zazzera, F.; Berz, M.

    2014-01-01

    A high order optimal control strategy is proposed in this work, based on the use of differential algebraic techniques. In the frame of orbital mechanics, differential algebra allows to represent, by high order Taylor polynomials, the dependency of the spacecraft state on initial conditions and environmental parameters. The resulting polynomials can be manipulated to obtain the high order expansion of the solution of two-point boundary value problems. Since the optimal control problem can be reduced to a two-point boundary value problem, differential algebra is used to compute the high order expansion of the solution of the optimal control problem about a reference trajectory. Whenever perturbations in the nominal conditions occur, new optimal control laws for perturbed initial and final states are obtained by the mere evaluation of polynomials. The performances of the method are assessed on lunar landing, rendezvous maneuvers, and a low-thrust Earth-Mars transfer.

  4. Reducing mortality for high risk surgical patients in the UK.

    PubMed

    Rogers, B A; Carrothers, A D; Jones, Chris

    2012-06-01

    Over 40 million surgical procedures are performed per annum in the USA and Europe, including several million patients who are considered to be high risk (Bennett-Guerrero et al 2003). Overall, the risk of death or major complications after surgery in the general surgical patient population is low, with a post-operative mortality rate of less than1% during the same hospital admission (Niskanen et al 2001).

  5. Bias-reduced and separation-proof conditional logistic regression with small or sparse data sets.

    PubMed

    Heinze, Georg; Puhr, Rainer

    2010-03-30

    Conditional logistic regression is used for the analysis of binary outcomes when subjects are stratified into several subsets, e.g. matched pairs or blocks. Log odds ratio estimates are usually found by maximizing the conditional likelihood. This approach eliminates all strata-specific parameters by conditioning on the number of events within each stratum. However, in the analyses of both an animal experiment and a lung cancer case-control study, conditional maximum likelihood (CML) resulted in infinite odds ratio estimates and monotone likelihood. Estimation can be improved by using Cytel Inc.'s well-known LogXact software, which provides a median unbiased estimate and exact or mid-p confidence intervals. Here, we suggest and outline point and interval estimation based on maximization of a penalized conditional likelihood in the spirit of Firth's (Biometrika 1993; 80:27-38) bias correction method (CFL). We present comparative analyses of both studies, demonstrating some advantages of CFL over competitors. We report on a small-sample simulation study where CFL log odds ratio estimates were almost unbiased, whereas LogXact estimates showed some bias and CML estimates exhibited serious bias. Confidence intervals and tests based on the penalized conditional likelihood had close-to-nominal coverage rates and yielded highest power among all methods compared, respectively. Therefore, we propose CFL as an attractive solution to the stratified analysis of binary data, irrespective of the occurrence of monotone likelihood. A SAS program implementing CFL is available at: http://www.muw.ac.at/msi/biometrie/programs.

  6. Amplitude modulation reduces loudness adaptation to high-frequency tones

    PubMed Central

    Wynne, Dwight P.; George, Sahara E.; Zeng, Fan-Gang

    2015-01-01

    Long-term loudness perception of a sound has been presumed to depend on the spatial distribution of activated auditory nerve fibers as well as their temporal firing pattern. The relative contributions of those two factors were investigated by measuring loudness adaptation to sinusoidally amplitude-modulated 12-kHz tones. The tones had a total duration of 180 s and were either unmodulated or 100%-modulated at one of three frequencies (4, 20, or 100 Hz), and additionally varied in modulation depth from 0% to 100% at the 4-Hz frequency only. Every 30 s, normal-hearing subjects estimated the loudness of one of the stimuli played at 15 dB above threshold in random order. Without any amplitude modulation, the loudness of the unmodulated tone after 180 s was only 20% of the loudness at the onset of the stimulus. Amplitude modulation systematically reduced the amount of loudness adaptation, with the 100%-modulated stimuli, regardless of modulation frequency, maintaining on average 55%–80% of the loudness at onset after 180 s. Because the present low-frequency amplitude modulation produced minimal changes in long-term spectral cues affecting the spatial distribution of excitation produced by a 12-kHz pure tone, the present result indicates that neural synchronization is critical to maintaining loudness perception over time. PMID:26233027

  7. Randomized Controlled Trial of a Spring Break Intervention to Reduce High-Risk Drinking

    PubMed Central

    Lee, Christine M.; Neighbors, Clayton; Lewis, Melissa A.; Kaysen, Debra; Mittmann, Angela; Geisner, Irene M.; Atkins, David C.; Zheng, Cheng; Garberson, Lisa A.; Kilmer, Jason R.; Larimer, Mary E.

    2014-01-01

    Objective While recent studies have documented high-risk drinking occurring during Spring Break (SB), particularly on SB trips with friends, published intervention studies are few. The present study evaluated the efficacy of Event Specific Prevention (ESP) strategies for reducing SB drinking among college students, compared to general prevention strategies and an assessment-only control group, as well as evaluated inclusion of peers in interventions and mode of intervention delivery (in-person vs. web). Method Participants included 783 undergraduates (56.1% women, average age 20.5) intending to go on a SB trip with friends as well as to drink heavily on at least one day of SB. Participants completed assessments prior to SB and were randomized to one of five intervention conditions: SB in-person BASICS, SB web BASICS, SB in-person BASICS with friend, SB web BASICS with friend, general BASICS, or an attention control condition. Follow-up assessment was completed one week after SB. Results While the SB web BASICS (with and without friends) and general BASICS interventions were not effective at reducing SB drinking, results indicated significant intervention effects for SB in-person BASICS in reducing SB drinking, particularly on trip days. Follow-up analyses indicated change in descriptive norms mediated treatment effect and reductions in drinking, while SB drinking intentions and positive expectancies did not. Conclusions Overall, results suggest an in-person SB-specific intervention is effective at reducing SB drinking, especially during trips. In contrast, interventions that contain non-SB related content, are web-based, or seek to involve friends may be less effective at reducing SB drinking. PMID:24491072

  8. A method for manufacturing superior set yogurt under reduced oxygen conditions.

    PubMed

    Horiuchi, H; Inoue, N; Liu, E; Fukui, M; Sasaki, Y; Sasaki, T

    2009-09-01

    The yogurt starters Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus are well-known facultatively anaerobic bacteria that can grow in oxygenated environments. We found that they removed dissolved oxygen (DO) in a yogurt mix as the fermentation progressed and that they began to produce acid actively after the DO concentration in the yogurt mix was reduced to 0 mg/kg, suggesting that the DO retarded the production of acid. Yogurt fermentation was carried out at 43 or 37 degrees C both after the DO reduction treatment and without prior treatment. Nitrogen gas was mixed and dispersed into the yogurt mix after inoculation with yogurt starter culture to reduce the DO concentration in the yogurt mix. The treatment that reduced DO concentration in the yogurt mix to approximately 0 mg/kg beforehand caused the starter culture LB81 used in this study to enter into the exponential growth phase earlier. Furthermore, the combination of reduced DO concentration in the yogurt mix beforehand and incubation at a lower temperature (37 degrees C) resulted in a superior set yogurt with a smooth texture and strong curd structure.

  9. Orexin-1 receptor antagonist SB-334867 reduces the acquisition and expression of cocaine-conditioned reinforcement and the expression of amphetamine-conditioned reward.

    PubMed

    Hutcheson, Daniel M; Quarta, Davide; Halbout, Briac; Rigal, Aurélie; Valerio, Enzo; Heidbreder, Christian

    2011-04-01

    Preclinical evidence suggests an important role of the brain orexin system in behaviours related to drug addiction. This study aimed at assessing the effect of the orexin-1 receptor antagonist SB-334867 on aspects of psychostimulant-conditioned behaviours that are thought to contribute to the maintenance of and relapse to psychostimulant drug use. Rats were first allowed to nose poke for cocaine infusions associated with a cue light presentation (conditioned stimulus; CS) over five daily sessions. Subsequently, drug-free rats were tested for the acquisition of a new response in which presses on a novel active lever led to the presentation of the previously paired CS. We tested SB-334867 in two conditions, SB-334867 was given either before each cocaine self-administration or before the initial four sessions of acquisition for a novel instrumental responding paired with the CS (conditioned reinforcement). The effect of SB-334867 was also tested on the expression of conditioned place preference to d-amphetamine. The rats treated with SB-334867 before each cocaine self-administration session subsequently showed reduced active lever pressing compared with controls in the initial days of the conditioned reinforcement. In the second study, untreated rats showed normal acquisition of discriminated responding preferential for the lever providing the cocaine cue. In contrast, SB-334867 decreased the number of active lever pressing (compared with the control) with significant effects in all sessions. Finally, SB-334867 blocked the expression of d-amphetamine-induced conditioned place preference. These results suggest that orexin-1 receptor antagonism could offer therapeutic potential in reducing the impact of psychostimulant-predictive stimuli that contribute to compulsive drug seeking in human drug users.

  10. Wooden breast condition results in reduced thaw loss in frozen-thawed broiler breast fillets

    USDA-ARS?s Scientific Manuscript database

    Wooden breast condition (WBC) is an emerging quality issue with broiler breast meat that significantly affects both raw and cooked meat properties. The objective of this study was to investigate the effects of WBC on meat water-holding capacity (WHC) estimated with different methods. Broiler breast ...

  11. Reduced Sensitivity to Minimum-Jerk Biological Motion in Autism Spectrum Conditions

    ERIC Educational Resources Information Center

    Cook, Jennifer; Saygin, Ayse Pinar; Swain, Rachel; Blakemore, Sarah-Jayne

    2009-01-01

    We compared psychophysical thresholds for biological and non-biological motion detection in adults with autism spectrum conditions (ASCs) and controls. Participants watched animations of a biological stimulus (a moving hand) or a non-biological stimulus (a falling tennis ball). The velocity profile of the movement was varied between 100% natural…

  12. Reduced Sensitivity to Minimum-Jerk Biological Motion in Autism Spectrum Conditions

    ERIC Educational Resources Information Center

    Cook, Jennifer; Saygin, Ayse Pinar; Swain, Rachel; Blakemore, Sarah-Jayne

    2009-01-01

    We compared psychophysical thresholds for biological and non-biological motion detection in adults with autism spectrum conditions (ASCs) and controls. Participants watched animations of a biological stimulus (a moving hand) or a non-biological stimulus (a falling tennis ball). The velocity profile of the movement was varied between 100% natural…

  13. Polyimide Nanocomposites Prepared from High-Temperature, Reduced Charge Organoclays

    NASA Technical Reports Server (NTRS)

    Delozier, D. M.; Orwoll, R. A.; Cahoon, J. F.; Ladislaw, J. S.; Smith, J. G., Jr.; Connell, J. W.

    2003-01-01

    Montmorillonite clays modified with the dihydrochloride salt of 1,3-bis(3-aminophenoxy)benzene (APB) were used in the preparation of polyimide/organoclay hybrid films. Organoclays with varying surface charge based upon APB were prepared and examined for their dispersion behavior in the polymer matrix. High molecular weight poly(amide acid) solutions were prepared in the presence of the organoclays. Films were cast and subsequently heated to 300C to cause imidization. The resulting nanocomposite films, containing 3 wt% of organoclay, were characterized by transmission electron microscopy and X-ray diffraction. The clay's cation exchange capacity (CEC) played a key role in determining the extent of dispersion in the polyimide matrix. Considerable dispersion was observed in some of the nanocomposite films. The most effective organoclay was found to have a CEC of 0.70 meq/g. Nanocomposite films prepared with 3-8 wt% of this organoclay were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and thin-film tensile testing. High levels of clay dispersion could be achieved even at the higher clay loadings. Results from mechanical testing revealed that while the moduli of the nanocomposites increased with increasing clay loadings, both strength and elongation decreased.

  14. Polyimide Nanocomposites Prepared from High-Temperature, Reduced Charge Organoclays

    NASA Technical Reports Server (NTRS)

    Delozier, D. M.; Orwoll, R. A.; Cahoon, J. F.; Ladislaw, J. S.; Smith, J. G., Jr.; Connell, J. W.

    2003-01-01

    Montmorillonite clays modified with the dihydrochloride salt of 1,3-bis(3-aminophenoxy)benzene (APB) were used in the preparation of polyimide/organoclay hybrid films. Organoclays with varying surface charge based upon APB were prepared and examined for their dispersion behavior in the polymer matrix. High molecular weight poly(amide acid) solutions were prepared in the presence of the organoclays. Films were cast and subsequently heated to 300C to cause imidization. The resulting nanocomposite films, containing 3 wt% of organoclay, were characterized by transmission electron microscopy and X-ray diffraction. The clay's cation exchange capacity (CEC) played a key role in determining the extent of dispersion in the polyimide matrix. Considerable dispersion was observed in some of the nanocomposite films. The most effective organoclay was found to have a CEC of 0.70 meq/g. Nanocomposite films prepared with 3-8 wt% of this organoclay were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and thin-film tensile testing. High levels of clay dispersion could be achieved even at the higher clay loadings. Results from mechanical testing revealed that while the moduli of the nanocomposites increased with increasing clay loadings, both strength and elongation decreased.

  15. Opaque minerals as keys for distinguishing oxidising and reducing diagenetic conditions in the Lower Triassic Bunter Sandstone, North German Basin

    NASA Astrophysics Data System (ADS)

    Weibel, R.; Friis, H.

    2004-07-01

    The diagenetic evolution in red and white/drab parts of the Bunter Sandstone from outcrops and wells in the North German Basin was unraveled by a detailed petrographical, mineralogical, and chemical study. The diagenetic sequences for the red and white/drab parts differ in the degree of alteration of iron-bearing detrital minerals and in the authigenic opaque minerals. In the white/drab parts, one typically sees reduction of red mica, dissolution of hematite and magnetite, and alteration of ilmenite and titanomagnetite to leucoxene. In contrast, the red parts commonly display oxidation of glauconite; red zonation in ooids; hematisation of magnetite, biotite, and magnetite host in titanomagnetite; and leucoxene replacement of the ilmenite lamellae in titanomagnetite. The red colour of the red bed host is due to red coatings of goethite needles and/or hematite needles. Goethite needles precipitated in the prevailing oxidising conditions, present shortly after deposition, whereas pseudomorphous replacement by hematite occurred during the burial process. The white/drab colour of the reduced areas is the original colour of the sediment. The black core in reduction spots is due to mineralization. Uranium and vanadium minerals (coffinite, montroseite, and V-illite) in reduction spots are located close to carbonate fragments, which probably contained organic matter. Isolated reduction spots may have formed immediately after deposition; inside these were clasts eroded from algal mats formed in the sabkha environment. The copper minerals typically occur in areas with high porosity, reflecting the importance of access to chloride-rich brines, which transported dissolved copper. When these brines reached reducing environments, chalcocite and chalcopyrite were precipitated, possibly by replacement of pyrite. In the red areas, these saline brines may also have promoted the second-stage alteration of ilmenite, in which leucoxene, the first-stage alteration product, was

  16. Highly variable Pliocene sea surface conditions in the Norwegian Sea

    NASA Astrophysics Data System (ADS)

    Bachem, Paul E.; Risebrobakken, Bjørg; De Schepper, Stijn; McClymont, Erin L.

    2017-09-01

    The Pliocene was a time of global warmth with small sporadic glaciations, which transitioned towards the larger-scale Pleistocene glacial-interglacial variability. Here, we present high-resolution records of sea surface temperature (SST) and ice-rafted debris (IRD) in the Norwegian Sea from 5.32 to 3.14 Ma, providing evidence that the Pliocene surface conditions of the Norwegian Sea underwent a series of transitions in response to orbital forcing and gateway changes. Average SSTs are 2 °C above the regional Holocene mean, with notable variability on millennial to orbital timescales. Both gradual changes and threshold effects are proposed for the progression of regional climate towards the Late Pliocene intensification of Northern Hemisphere glaciation. Cooling from 4.5 to 4.3 Ma may be linked to the onset of poleward flow through the Bering Strait. This cooling was further intensified by a period of cool summers due to weak obliquity forcing. A 7 °C warming of the Norwegian Sea at 4.0 Ma suggests a major increase in northward heat transport from the North Atlantic, leading to an enhanced zonal SST gradient in the Nordic Seas, which may be linked to the expansion of sea ice in the Arctic and Nordic Seas. A warm Norwegian Sea and enhanced zonal temperature gradient between 4.0 and 3.6 Ma may have been a priming factor for increased glaciation around the Nordic Seas due to enhanced evaporation and precipitation at high northern latitudes.

  17. Origins of life and biochemistry under high-pressure conditions.

    PubMed

    Daniel, Isabelle; Oger, Philippe; Winter, Roland

    2006-10-01

    Life on Earth can be traced back to as far as 3.8 billion years (Ga) ago. The catastrophic meteoritic bombardment ended between 4.2 and 3.9 Ga ago. Therefore, if life emerged, and we know it did, it must have emerged from nothingness in less than 400 million years. The most recent scenarios of Earth accretion predict some very unstable physico-chemical conditions at the surface of Earth, which, in such a short time period, would impede the emergence of life from a proto-biotic soup. A possible alternative would be that life originated in the depth of the proto-ocean of the Hadean Earth, under high hydrostatic pressure. The large body of water would filter harmful radiation and buffer physico-chemical variations, and therefore would provide a more stable radiation-free environment for pre-biotic chemistry. After a short introduction to Earth history, the current tutorial review presents biological and physico-chemical arguments in support of high-pressure origin for life on Earth.

  18. High Performance Palladium Supported on Nanoporous Carbon under Anhydrous Condition

    NASA Astrophysics Data System (ADS)

    Yang, Zehui; Ling, Ying; Zhang, Yunfeng; Xu, Guodong

    2016-11-01

    Due to the high cost of polymer electrolyte fuel cells (PEFCs), replacing platinum (Pt) with some inexpensive metal was carried out. Here, we deposited palladium nanoparticles (Pd-NPs) on nanoporous carbon (NC) after wrapping by poly[2,2‧-(2,6-pyridine)-5,5‧-bibenzimidazole] (PyPBI) doped with phosphoric acid (PA) and the Pd-NPs size was successfully controlled by varying the weight ratio between Pd precursor and carbon support doped with PA. The membrane electrode assembly (MEA) fabricated from the optimized electrocatalyst with 0.05 mgPd cm-2 for both anode and cathode sides showed a power density of 76 mW cm-2 under 120 °C without any humidification, which was comparable to the commercial CB/Pt, 89 mW cm-2 with 0.45 mgPt cm-2 loaded in both anode and cathode. Meanwhile, the power density of hybrid MEA with 0.45 mgPt cm-2 in cathode and 0.05 mgPd cm-2 in anode reached 188 mW cm-2. The high performance of the Pt-free electrocatalyst was attributed to the porous structure enhancing the gas diffusion and the PyPBI-PA facilitating the proton conductivity in catalyst layer. Meanwhile, the durability of Pd electrocatalyst was enhanced by coating with acidic polymer. The newly fabricated Pt-free electrocatalyst is extremely promising for reducing the cost in the high-temperature PEFCs.

  19. High Performance Palladium Supported on Nanoporous Carbon under Anhydrous Condition

    PubMed Central

    Yang, Zehui; Ling, Ying; Zhang, Yunfeng; Xu, Guodong

    2016-01-01

    Due to the high cost of polymer electrolyte fuel cells (PEFCs), replacing platinum (Pt) with some inexpensive metal was carried out. Here, we deposited palladium nanoparticles (Pd-NPs) on nanoporous carbon (NC) after wrapping by poly[2,2′-(2,6-pyridine)-5,5′-bibenzimidazole] (PyPBI) doped with phosphoric acid (PA) and the Pd-NPs size was successfully controlled by varying the weight ratio between Pd precursor and carbon support doped with PA. The membrane electrode assembly (MEA) fabricated from the optimized electrocatalyst with 0.05 mgPd cm−2 for both anode and cathode sides showed a power density of 76 mW cm−2 under 120 °C without any humidification, which was comparable to the commercial CB/Pt, 89 mW cm−2 with 0.45 mgPt cm−2 loaded in both anode and cathode. Meanwhile, the power density of hybrid MEA with 0.45 mgPt cm−2 in cathode and 0.05 mgPd cm−2 in anode reached 188 mW cm−2. The high performance of the Pt-free electrocatalyst was attributed to the porous structure enhancing the gas diffusion and the PyPBI-PA facilitating the proton conductivity in catalyst layer. Meanwhile, the durability of Pd electrocatalyst was enhanced by coating with acidic polymer. The newly fabricated Pt-free electrocatalyst is extremely promising for reducing the cost in the high-temperature PEFCs. PMID:27811971

  20. Reduced length fibre Bragg gratings for high frequency acoustic sensing

    NASA Astrophysics Data System (ADS)

    Davis, Claire; Robertson, David; Brooks, Chris; Norman, Patrick; Rosalie, Cedric; Rajic, Nik

    2014-12-01

    In-fibre Bragg gratings (FBGs) are now well established for applications in acoustic sensing. The upper frequency response limit of the Bragg grating is determined by its gauge length, which has typically been limited to about 1 mm for commercially available Type 1 gratings. This paper investigates the effect of FBG gauge length on frequency response for sensing of acoustic waves. The investigation shows that the ratio of wavelength to FBG length must be at least 8.8 in order to reliably resolve the strain response without significant gain roll-off. Bragg gratings with a gauge length of 200 µm have been fabricated and their capacity to measure low amplitude high frequency acoustic strain fields in excess of 2 MHz is experimentally demonstrated. The ultimate goal of this work is to enhance the sensitivity of acoustic damage detection techniques by extending the frequency range over which acoustic waves may be reliably measured using FBGs.

  1. Reduced coagulation at high altitude identified by thromboelastography.

    PubMed

    Martin, Daniel S; Pate, Jim S; Vercueil, Andre; Doyle, Patrick W; Mythen, Michael G; Grocott, Mike P W

    2012-06-01

    The impact of hypoxaemia on blood coagulation remains unclear despite use of a variety of measures to address the issue. We report the first use of thromboelastography (TEG) at high altitude to describe the dynamics of clot formation in whole blood samples. Seventeen healthy volunteers ascended to 5,300 m following an identical ascent profile; TEG measurements at 4,250 m and 5,300 m were compared with those from sea level. Peripheral oxygen saturation (SpO2) and haematocrit were also measured. Ascent resulted in a decline in SpO2 from 97.8 (± 1.2) % at sea level to 86.9 (± 3.3) % at 4,250 m and 79.5 (± 5.8) % at 5,300 m (p<0.001); haematocrit rose from 43.7 (± 2.8) % at sea level, to 46.7 (± 3.9) % and 52.6 (± 3.2) % at 4,250 m and 5,300 m, respectively (p<0.01). TEG reaction (R)-time and kinetic (K)-time were both increased at 5,300 m compared to sea level, 8.95 (± 1.37) minutes (min) to 11.69 (± 2.91) min (p=0.016) and 2.40 (± 0.66) min to 4.99 (± 1.67) min (p<0.001), respectively. Additionally the alpha (α)-angle was decreased from 57.7 (± 8.2) to 51.6 (± 6.4) (p<0.001). There was no change in maximum amplitude (MA) on ascent to altitude. These changes are consistent with an overall pattern of slowed coagulation at high altitude.

  2. Local charge transport properties of hydrazine reduced monolayer graphene oxide sheets prepared under pressure condition

    SciTech Connect

    Ryuzaki, Sou Meyer, Jakob A. S.; Petersen, Søren; Nørgaard, Kasper; Hassenkam, Tue; Laursen, Bo W.

    2014-09-01

    Charge transport properties of chemically reduced graphene oxide (RGO) sheets prepared by treatment with hydrazine were examined using conductive atomic force microscopy. The current-voltage (I-V) characteristics of monolayer RGO sheets prepared under atmospheric pressure followed an exponentially increase due to 2D variable-range hopping conduction through small graphene domains in an RGO sheet containing defect regions of residual sp{sup 3} carbon clusters bonded to oxygen groups, whereas RGO sheets prepared in a closed container under moderate pressure showed linear I-V characteristics with a conductivity of 267.2−537.5 S/m. It was found that the chemical reduction under pressure results in larger graphene domains (sp{sup 2} networks) in the RGO sheets when compared to that prepared under atmospheric pressure, indicating that the present reduction of GO sheets under the pressure is one of the effective methods to make well-reduced GO sheets.

  3. Implications of macromolecular crowding and reducing conditions for in vitro ribosome construction

    PubMed Central

    Fritz, Brian R.; Jamil, Osman K.; Jewett, Michael C.

    2015-01-01

    In vitro construction of Escherichia coli ribosomes could elucidate a deeper understanding of these complex molecular machines and make possible the production of synthetic variants with new functions. Toward this goal, we recently developed an integrated synthesis, assembly and translation (iSAT) system that allows for co-activation of ribosomal RNA (rRNA) transcription and ribosome assembly, mRNA transcription and protein translation without intact cells. Here, we discovered that macromolecular crowding and reducing agents increase overall iSAT protein synthesis; the combination of 6% w/v Ficoll 400 and 2 mM DTBA yielded approximately a five-fold increase in overall iSAT protein synthesis activity. By utilizing a fluorescent RNA aptamer, fluorescent reporter proteins and ribosome sedimentation analysis, we showed that crowding agents increase iSAT yields by enhancing translation while reducing agents increase rRNA transcription and ribosome assembly. Finally, we showed that iSAT ribosomes possess ∼70% of the protein synthesis activity of in vivo-assembled E. coli ribosomes. This work improves iSAT protein synthesis through the addition of crowding and reducing agents, provides a thorough understanding of the effect of these additives within the iSAT system and demonstrates how iSAT allows for manipulation and analysis of ribosome biogenesis in the context of an in vitro transcription-translation system. PMID:25897121

  4. High Energy Boundary Conditions for a Cartesian Mesh Euler Solver

    NASA Technical Reports Server (NTRS)

    Pandya, Shishir; Murman, Scott; Aftosmis, Michael

    2003-01-01

    Inlets and exhaust nozzles are common place in the world of flight. Yet, many aerodynamic simulation packages do not provide a method of modelling such high energy boundaries in the flow field. For the purposes of aerodynamic simulation, inlets and exhausts are often fared over and it is assumed that the flow differences resulting from this assumption are minimal. While this is an adequate assumption for the prediction of lift, the lack of a plume behind the aircraft creates an evacuated base region thus effecting both drag and pitching moment values. In addition, the flow in the base region is often mis-predicted resulting in incorrect base drag. In order to accurately predict these quantities, a method for specifying inlet and exhaust conditions needs to be available in aerodynamic simulation packages. A method for a first approximation of a plume without accounting for chemical reactions is added to the Cartesian mesh based aerodynamic simulation package CART3D. The method consists of 3 steps. In the first step, a components approach where each triangle is assigned a component number is used. Here, a method for marking the inlet or exhaust plane triangles as separate components is discussed. In step two, the flow solver is modified to accept a reference state for the components marked inlet or exhaust. In the third step, the flow solver uses these separated components and the reference state to compute the correct flow condition at that triangle. The present method is implemented in the CART3D package which consists of a set of tools for generating a Cartesian volume mesh from a set of component triangulations. The Euler equations are solved on the resulting unstructured Cartesian mesh. The present methods is implemented in this package and its usefulness is demonstrated with two validation cases. A generic missile body is also presented to show the usefulness of the method on a real world geometry.

  5. High salinity and UVR synergistically reduce the photosynthetic performance of an intertidal benthic diatom.

    PubMed

    Wu, Yaping; Zhu, Yanchen; Xu, Juntian

    2017-09-01

    The intertidal flat is an important intermediate ecosystem characterized by abrupt fluctuations of some environmental factors. As a major contributor to coastal primary productivity, benthic diatoms have to cope up with these fluctuating conditions, such as variations in salinity and light. In this study, we used a typical benthic diatom, Nitzschia sp., to investigate how the photosynthetic performance of a benthic species responded to coupled stresses of high salinity and simulated sunlight. Results showed that their responses were largely dependent on the spectra of light they received. Further, ultraviolet radiation (UVR) interacted with high salinity more effectively than photosynthetically active radiation (PAR), which synergistically reduced the photochemical performance of photosystem II (PSII). The different responses to PAR and UVR were mainly attributed to the repair processes of PSII. Under high salinity, particularly for cells exposed to UVR, the repair rate was significantly lower than those under the control treatment. The present work suggests that UVR, rather than PAR, could be more important in influencing the benthic diatom under high salinity conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. High-pressure highly reduced nitrides and oxides from chromitite of a Tibetan ophiolite

    PubMed Central

    Dobrzhinetskaya, Larissa F.; Wirth, Richard; Yang, Jingsui; Hutcheon, Ian D.; Weber, Peter K.; Green, Harry W.

    2009-01-01

    The deepest rocks known from within Earth are fragments of normal mantle (≈400 km) and metamorphosed sediments (≈350 km), both found exhumed in continental collision terranes. Here, we report fragments of a highly reduced deep mantle environment from at least 300 km, perhaps very much more, extracted from chromite of a Tibetan ophiolite. The sample consists, in part, of diamond, coesite-after-stishovite, the high-pressure form of TiO2, native iron, high-pressure nitrides with a deep mantle isotopic signature, and associated SiC. This appears to be a natural example of the recently discovered disproportionation of Fe2+ at very high pressure and consequent low oxygen fugacity (fO2) in deep Earth. Encapsulation within chromitite enclosed within upwelling solid mantle rock appears to be the only vehicle capable of transporting these phases and preserving their low-fO2 environment at the very high temperatures of oceanic spreading centers. PMID:19880742

  7. Small Scale Trace Contaminant Testing of SA9T at Ambient and Reduced Pressure Conditions

    NASA Technical Reports Server (NTRS)

    Broerman, Craig; Sweterlitsch, Jeffrey

    2011-01-01

    A principle concern for air revitalization technology in a closed loop system is the capability to control carbon dioxide (CO2) and humidity (H2O). An amine based sorbent technology, SA9T, has long been evaluated for use in this application and several programs are evaluating it for use in both a cabin as well as space suit applications. While the CO2 and H2O performance of the sorbent has been tested extensively, the question of how trace contaminants impact performance requires further evaluation. This paper presents experimental results of small scale SA9T testing that was performed over a variety of test conditions and with a variety of trace contaminants. Testing evaluated the ability of SA9T media to sufficiently remove CO2 and H2O after exposure to a fully saturated trace contaminant at ambient conditions. Testing also evaluated the impact of CO2 and H2O removal performance at suit loop pressures during cyclic operation with a constant inlet contaminant load. In addition, testing evaluated the performance of SA9T at ambient conditions in a continuous 30-day test with a mixed trace contaminant stream.

  8. Bench-Scale Trace Contaminant Testing of SA9T at Ambient and Reduced Pressure Conditions

    NASA Technical Reports Server (NTRS)

    Broerman, Craig; Sweterlitsch, Jeff

    2011-01-01

    A principal concern for air revitalization technology in a closed loop system is the capability to control carbon dioxide (CO2) and humidity (H2O). An amine based sorbent technology, SA9T, has been evaluated for use in this application and several programs are evaluating it for use in both cabin and space suit applications. While the CO2 and H2O performance of the sorbent has been tested extensively, the question of how trace contaminants impact performance requires further evaluation. This paper presents experimental results of bench-scale SA9T testing that was performed under a variety of test conditions and with several different trace contaminants. Tests were conducted to determine if the capacity of the SA9T media to sufficiently remove CO2 and H2O is compromised after exposure to a fully saturated trace contaminant at ambient conditions. Tests also were conducted to evaluate the performance of SA9T at ambient conditions in a continuous 30-day test with a mixed trace contaminant stream. In addition, testing also evaluated the impact of CO2 and H2O removal performance at suit loop pressures (29.6 KPa/4.3 psia) during cyclic operation with a constant inlet contaminant load.

  9. ATM gene single nucleotide polymorphisms predict regimen-related gastrointestinal toxicity in patients allografted after reduced conditioning.

    PubMed

    Kuba, Adam; Raida, Ludek; Mrazek, Frantisek; Schneiderova, Petra; Kriegova, Eva; Furst, Tomas; Furstova, Jana; Faber, Edgar; Ambruzova, Zuzana; Papajik, Tomas

    2015-06-01

    Polymorphisms of genes involved in innate and adaptive immunity have become an object of major interest in regard to hematopoietic stem cell transplantation (HSCT) complications. Regimen-related gastrointestinal toxicity (RR-GIT) is the dominant complication during the pre-engraftment period and has been linked to increased risk of graft-versus-host disease (GVHD) development. According to our hypothesis, functional variants of genes participating in DNA damage response (DDR) may have an impact on the extent of tissue damage caused by the conditioning regimen. In our single-center study, we analyzed 62 patients who underwent HSCT from HLA-identical donors after reduced conditioning. The patients were genotyped for 5 single nucleotide polymorphisms (SNPs, rs4585 T/G, rs189037 A/G, rs227092 T/G, rs228590 C/T, and rs664677 T/C) of the ATM gene-the essential member of the DDR pathways, using allele-specific matrix-assisted laser desorption/ionization, time-of-flight (MALDI-TOF) mass spectrometry assay. Because of almost absolute linkage disequilibrium observed among all 5 SNPs, association of 2 major ATM haplotypes (ATM1/ATM2) with RR-GIT and acute GVHD (aGVHD) was analyzed. Importantly, the univariate and multivariate analysis showed that patients homozygous for ATM2 haplotype (rs4585*T, rs189037*A, rs227092*T, rs228590*C, and rs664677*T) are more likely to suffer from high-grade RR-GIT than ATM1 homozygous patients. The association with aGVHD was not significant. To our knowledge, this is the first report showing the ATM gene variability in relation to RR-GIT in the allogeneic HSCT setting. Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  10. Stimulus preexposure reduces generalization of conditioned taste aversions between alcohol and non-alcohol flavors in infant rats.

    PubMed

    Chotro, M Gabriela; Alonso, Gumersinda

    2003-02-01

    Results of 3 experiments showed that infant rats (age 13-17 days) generalize conditioned taste aversions between alcohol and non-alcohol tastes such as a mixture of sucrose and quinine, apple cider vinegar, or coffee. Nonreinforced preexposure to those tastes reduced generalized aversions between them. Generalization between alcohol and sucrose-quinine was reduced not only after preexposure to both tastes, but also when only the nonconditioned taste was preexposed, whereas with alcohol and vinegar, both tastes had to be preexposed to obtain that effect. In no case was generalization reduced when only the to-be-conditioned taste was preexposed. Previous experience with alcohol alone, as well as with similar gustatory stimuli, may enhance subjects' ability to differentiate them during infantile stages in rats.

  11. Muddy conditions reduce hygiene and lying time in dairy cattle and increase time spent on concrete.

    PubMed

    Chen, Jennifer M; Stull, Carolyn L; Ledgerwood, David N; Tucker, Cassandra B

    2017-03-01

    Dairy cattle spend less time lying and show signs of increased stress when housed in rainy and windy conditions, but no work has separated the effects of exposure to inclement weather from muddy conditions underfoot. Our objective was to evaluate the effects of muddy conditions alone on lying behavior, hygiene, and physiological responses. We housed pairs of pregnant, nonlactating dairy cattle (n = 12; 6 primigravid heifers, 6 multiparous cows) in enclosed pens with dirt floors and a concrete feed apron. Cattle were exposed to 3 levels of soil moisture: 90 (dry), 74 (muddy), or 67% (very muddy) dry matter for 5 d each in a replicated 3 × 3 Latin square design. Lying time was measured on all days with data loggers, and lying locations and postures were recorded on the final day of each treatment. Before and after each treatment, blood samples were collected, and the percentage of dirty surface area was measured on the udder, hind leg, and side of each animal. Cattle spent less time lying down in muddier conditions, especially in the first 24 h of exposure, when cows and heifers spent only 3.2 and 5.8 h, respectively, lying down in the muddiest treatment compared with 12.5 and 12.7 h on dry soil. When the soil was dry, cattle never chose to lie down on concrete, but in muddier conditions they spent a greater proportion of their lying time on concrete (mean ± SE: 56 ± 14 and 10 ± 8% in the very muddy and muddy treatments, respectively). The shift in lying location was more marked for heifers, and all 6 spent ≥87% of their lying time on concrete in the muddiest treatment. When cattle chose to lie down on wetter soil, they limited the surface area exposed to their surroundings by tucking their legs beneath their bodies (mean ± SE: 30 ± 11, 15 ± 4, and 5 ± 2% of lying observations in the very muddy, muddy, and dry treatments, respectively). Despite cattle spending less time on wetter soil, all 3 measured body parts became dirtier in muddier conditions (1.4-, 1

  12. Final Report Construction of Whole Genome Microarrays, and Expression Analysis of Desulfovibrio vulgaris cells in Metal-Reducing Conditions

    SciTech Connect

    M.W. Fields; J.D. Wall; J. Keasling; J. Zhou

    2008-05-15

    We continue to utilize the oligonucleotide microarrays that were constructed through funding with this project to characterize growth responses of Desulfovibrio vulgaris relevant to metal-reducing conditions. To effectively immobilize heavy metals and radionuclides via sulfate-reduction, it is important to understand the cellular responses to adverse factors observed at contaminated subsurface environments (e.g., nutrients, pH, contaminants, growth requirements and products). One of the major goals of the project is to construct whole-genome microarrays for Desulfovibrio vulgaris. First, in order to experimentally establish the criteria for designing gene-specific oligonucleotide probes, an oligonucleotide array was constructed that contained perfect match (PM) and mismatch (MM) probes (50mers and 70mers) based upon 4 genes. The effects of probe-target identity, continuous stretch, mismatch position, and hybridization free energy on specificity were examined. Little hybridization was observed at a probe-target identity of <85% for both 50mer and 70mer probes. 33 to 48% of the PM signal intensities were detected at a probe-target identity of 94% for 50mer oligonucleotides, and 43 to 55% for 70mer probes at a probe-target identity of 96%. When the effects of sequence identity and continuous stretch were considered independently, a stretch probe (>15 bases) contributed an additional 9% of the PM signal intensity compared to a non-stretch probe (< 15 bases) at the same identity level. Cross-hybridization increased as the length of continuous stretch increased. A 35-base stretch for 50mer probes or a 50-base stretch for 70mer probes had approximately 55% of the PM signal. Mismatches should be as close to the middle position of an oligonucleotide probe as possible to minimize cross-hybridization. Little cross-hybridization was observed for probes with a minimal binding free energy greater than -30 kcal/mol for 50mer probes or -40 kcal/mol for 70mer probes. Based on the

  13. Impact of iron-reducing bacteria on the corrosion rate of carbon steel under simulated geological disposal conditions.

    PubMed

    Schütz, Marta K; Schlegel, Michel L; Libert, Marie; Bildstein, Olivier

    2015-06-16

    The current projects for the disposal of high-level radioactive waste rely on underground burial and confinement by metallic envelopes that are susceptible to corrosion processes. The impact of microbial activity must be fully clarified in order to provide biological parameters for predictive reactive transport models. This study investigates the impact of hydrogenotrophic iron-reducing bacteria (Shewanella oneidensis strain MR-1) on the corrosion rate of carbon steel under simulated geological disposal conditions by using a geochemical approach. It was found that corrosion damage changes mostly according to the experimental solution (i.e., chemical composition). Magnetite and vivianite were identified as the main corrosion products. In the presence of bacteria, the corrosion rate increased by a factor of 1.3 (according to weight loss analysis) to 1.8 (according to H2 measurements), and the detected amount of magnetite diminished. The mechanism likely to enhance corrosion is the destabilization and dissolution of the passivating magnetite layer by reduction of structural Fe(III) coupled to H2 oxidation.

  14. Leaching and accumulation of trace elements in sulfate reducing granular sludge under concomitant thermophilic and low pH conditions.

    PubMed

    Gonzalez-Gil, G; Lopes, S I C; Saikaly, P E; Lens, P N L

    2012-12-01

    The leaching and/or accumulation of trace elements in sulfate reducing granular sludge systems was investigated. Two thermophilic up-flow anaerobic sludge bed (UASB) reactors operated at pH 5 were fed with sucrose (4 gCOD l(reactor)(-1)d(-1)) and sulfate at different COD/SO(4)(2-) ratios. During the start-up of such acidogenic systems, an initial leaching of trace elements from the inoculum sludge occurred regardless of trace elements supplementation in the reactor influent. The granular sludge maintained the physical structure despite high Fe leaching. After start-up and nonetheless the acidic conditions, Co, Ni, Cu, Zn, Mo and Se were retained or accumulated by the sludge when added. Particularly, Ni and Co accumulated in the carbonates and exchangeable fractions ensuring potential bioavailability. Otherwise, the initial stock in the inoculum sludge sufficed to operate the process for nearly 1 year without supplementation of trace elements and no significant sludge wash-out occurred.

  15. Mycophenolate mofetil and cyclosporine for graft-versus-host disease prophylaxis following reduced intensity conditioning allogeneic stem cell transplantation.

    PubMed

    Mohty, M; de Lavallade, H; Faucher, C; Bilger, K; Vey, N; Stoppa, A-M; Gravis, G; Coso, D; Viens, P; Gastaut, J-A; Blaise, D

    2004-09-01

    The use of reduced intensity conditioning (RIC) regimens for allogeneic stem cell transplantation (allo-SCT) can result in a significant decrease in early procedure-related toxicity in patients not eligible for standard myeloablative regimens. However, acute graft-versus-host disease (aGVHD) remains a matter of concern after RIC allo-SCT, and its incidence might be expected to be higher in elderly and high-risk patients. This report investigated mycophenolate mofetil (MMF) and cyclosporin A (CsA) combination (n=14) in comparison to CsA alone (n=20) for GVHD prophylaxis in cancer patients aged over 50 years (27 haematological malignancies and seven solid tumours) receiving an HLA-identical sibling antithymocyte-globulin (ATG)-based RIC allo-SCT. Baseline demographic characteristics and risk factors for aGVHD were comparable between both groups. Although MMF administration was not associated with any significant toxicity, the cumulative incidence of any form of GVHD was comparable between both groups (cumulative incidence of grade II-IV aGVHD, 50% (95% CI, 28-72%) for CsA alone, as compared to 64% (95% CI, 39-89%) to CsA and MMF, P=NS), suggesting that adjunction of MMF to CsA is feasible, but does not translate towards a significant reduction of aGVHD, at least in the context ATG-based RIC allo-SCT.

  16. Mackinawite (FeS) Reduces Mercury(II) under Sulfidic Conditions

    PubMed Central

    2015-01-01

    Mercury (Hg) is a toxicant of global concern that accumulates in organisms as methyl Hg. The production of methyl Hg by anaerobic bacteria may be limited in anoxic sediments by the sequestration of divalent Hg [Hg(II)] into a solid phase or by the formation of elemental Hg [Hg(0)]. We tested the hypothesis that nanocrystalline mackinawite (tetragonal FeS), which is abundant in sediments where Hg is methylated, both sorbs and reduces Hg(II). Mackinawite suspensions were equilibrated with dissolved Hg(II) in batch reactors. Examination of the solid phase using Hg LIII-edge extended X-ray absorption fine structure (EXAFS) spectroscopy showed that Hg(II) was indeed reduced in FeS suspensions. Measurement of purgeable Hg using cold vapor atomic fluorescence spectrometry (CVAFS) from FeS suspensions and control solutions corroborated the production of Hg(0) that was observed spectroscopically. However, a fraction of the Hg(II) initially added to the suspensions remained in the divalent state, likely in the form of β-HgS-like clusters associated with the FeS surface or as a mixture of β-HgS and surface-associated species. Complexation by dissolved S(-II) in anoxic sediments hinders Hg(0) formation, but, by contrast, Hg(II)–S(-II) species are reduced in the presence of mackinawite, producing Hg(0) after only 1 h of reaction time. The results of our work support the idea that Hg(0) accounts for a significant fraction of the total Hg in wetland and estuarine sediments. PMID:25180562

  17. High Fat High Sugar Diet Reduces Voluntary Wheel Running in Mice Independent of Sex Hormone Involvement

    PubMed Central

    Vellers, Heather L.; Letsinger, Ayland C.; Walker, Nicholas R.; Granados, Jorge Z.; Lightfoot, J. Timothy

    2017-01-01

    Introduction: Indirect results in humans suggest that chronic overfeeding decreases physical activity with few suggestions regarding what mechanism(s) may link overfeeding and decreased activity. The primary sex hormones are known regulators of activity and there are reports that chronic overfeeding alters sex hormone levels. Thepurpose of this study was to determine if chronic overfeeding altered wheel running through altered sex hormone levels. Materials and Methods: C57BL/6J mice were bred and the pups were weaned at 3-weeks of age and randomly assigned to either a control (CFD) or high fat/high sugar (HFHS) diet for 9–11 weeks depending on activity analysis. Nutritional intake, body composition, sex hormone levels, and 3-day and 2-week wheel-running activity were measured. Additionally, groups of HFHS animals were supplemented with testosterone (males) and 17β-estradiol (females) to determine if sex hormone augmentation altered diet-induced changes in activity. Results: 117 mice (56♂, 61♀) were analyzed. The HFHS mice consumed significantly more calories per day than CFD mice (male: p < 0.0001; female: p < 0.0001) and had significantly higher body fat (male: p < 0.0001; female: p < 0.0001). The HFHS diet did not reduce sex hormone levels, but did significantly reduce acute running-wheel distance in male (p = 0.05, 70 ± 28%) and female mice (p = 0.02, 57 ± 26%). In animals that received hormone supplementation, there was no significant effect on activity levels. Two-weeks of wheel access was not sufficient to alter HFHS-induced reductions in activity or increases in body fat. Conclusion: Chronic overfeeding reduces wheel running, but is independent of the primary sex hormones. PMID:28890701

  18. High Fat High Sugar Diet Reduces Voluntary Wheel Running in Mice Independent of Sex Hormone Involvement.

    PubMed

    Vellers, Heather L; Letsinger, Ayland C; Walker, Nicholas R; Granados, Jorge Z; Lightfoot, J Timothy

    2017-01-01

    Introduction: Indirect results in humans suggest that chronic overfeeding decreases physical activity with few suggestions regarding what mechanism(s) may link overfeeding and decreased activity. The primary sex hormones are known regulators of activity and there are reports that chronic overfeeding alters sex hormone levels. Thepurpose of this study was to determine if chronic overfeeding altered wheel running through altered sex hormone levels. Materials and Methods: C57BL/6J mice were bred and the pups were weaned at 3-weeks of age and randomly assigned to either a control (CFD) or high fat/high sugar (HFHS) diet for 9-11 weeks depending on activity analysis. Nutritional intake, body composition, sex hormone levels, and 3-day and 2-week wheel-running activity were measured. Additionally, groups of HFHS animals were supplemented with testosterone (males) and 17β-estradiol (females) to determine if sex hormone augmentation altered diet-induced changes in activity. Results: 117 mice (56♂, 61♀) were analyzed. The HFHS mice consumed significantly more calories per day than CFD mice (male: p < 0.0001; female: p < 0.0001) and had significantly higher body fat (male: p < 0.0001; female: p < 0.0001). The HFHS diet did not reduce sex hormone levels, but did significantly reduce acute running-wheel distance in male (p = 0.05, 70 ± 28%) and female mice (p = 0.02, 57 ± 26%). In animals that received hormone supplementation, there was no significant effect on activity levels. Two-weeks of wheel access was not sufficient to alter HFHS-induced reductions in activity or increases in body fat. Conclusion: Chronic overfeeding reduces wheel running, but is independent of the primary sex hormones.

  19. Thermo-economic approach for absorption air condition onboard high-speed crafts

    NASA Astrophysics Data System (ADS)

    Seddiek, Ibrahim S.; Mosleh, Mosaad; Banawan, Adel A.

    2012-12-01

    High-speed crafts suffer from losing a huge amount of their machinery energy in the form of heat loss with the exhaust gases. This will surely increase the annual operating cost of this type of ships and an adverse effect on the environment. This paper introduces a suggestion that may contribute to overcoming such problems. It presents the possibility of reusing the energy lost by the ships' exhaust gases as heating source for an absorption air condition unit onboard high-speed crafts. As a numerical example; the proposed method was investigated at a high-speed craft operating in Red Sea between Egypt and the Kingdom of Saudi Arabia. The results obtained are very satisfactory. It showed the possibility of providing the required ship's air condition cooling load during sailing and in port. Economically, this will reduce the annual ship's operating cost. Moreover, it will achieve a valuable reduction of ship's emissions.

  20. Reduced graphene oxide with ultrahigh conductivity as carbon coating layer for high performance sulfur@reduced graphene oxide cathode

    NASA Astrophysics Data System (ADS)

    Zhao, Hongbin; Peng, Zhenhuan; Wang, Wenjun; Chen, Xikun; Fang, Jianhui; Xu, Jiaqiang

    2014-01-01

    We developed hydrogen iodide (HI) reduction of rGO and surfactant-assisted chemical reaction- deposition method to form hybrid material of sulfur (S) encapsulated in reduced graphene oxide (rGO) sheets for rechargeable lithium batteries. The surfactant-assisted chemical reaction-deposition method strategy provides intimate contact between the S and graphene oxide. Chemical reduced rGO with high conductivity as carbon coating layer prevented the dissolution of polysulfide ions and improved the electron transfer. This novel core-shell structured S@rGO composites with high S content showed high reversible capacity, good discharge capacity retention and enhanced rate capability used as cathodes in rechargeable Li/S cells. We demonstrated here that an electrode prepared from a S@rGO with up to 85 wt% S maintains a stable discharge capacity of about 980 mAh g-1 at 0.05 C and 570 mAh g-1 at 1C after 200 cycles charge/discharge. These results emphasize the importance of rGO with high electrical conductivity after HI-reduced rGO homogeneously coating on the surface of S, therefore, effectively alleviating the shuttle phenomenon of polysulfides in organic electrolyte. Our surfactant-assisted chemical reaction-HI reduction approach should offer a new technique for the design and synthesis of battery electrodes based on highly conducting carbon materials.

  1. Biologically-Induced Precipitation of Minerals in a Medium with Zinc Under Sulfate-Reducing Conditions.

    PubMed

    Wolicka, Dorota; Borkowski, Andrzej; Jankiewicz, Urszula; Stępień, Wojciech; Kowalczyk, Paweł

    2015-01-01

    Sulfate-reducing microbial communities were enriched from soils collected in areas with crude-oil exploitation. Cultures were grown in modified Postgate C medium and minimal medium, with ethanol or lactate as an electron donor. The batch cultures were grown with addition of zinc in concentrations of 100-700 mg/l. A lack of increased protein concentration in the solutions compared with the control batch, was noted in cultures containing over 200 mg Zn2+/l. The 16S rRNA method was applied to determine the specific composition of the selected microorganism communities. The analysis indicated the presence of Desulfovibrio spp., Desulfobulbus spp. and Desulfotomaculum spp. in the communities. Diffractometric analysis indicated the presence of biogenic sphalerite in cultures with 100 and 200 mg Zn2+/l and elemental sulfur in cultures with 200 mg Zn2+/l. Other post culture sediments (300-700 mg Zn2+/l) contained only hopeite [Zn3(PO4)2·4H2O] formed abiotically during the experiment, which was confirmed by studies of the activity of sulfate-reducing microbial communities.

  2. Volume stabilization of high MgO cement: Effect of curing conditions and fly ash addition

    SciTech Connect

    Ali, M.M.; Mullick, A.K.

    1998-11-01

    Hydration of high MgO cement paste under autoclave condition causes the rapid formation and crystallization of magnesium hydroxide and leads to the creation of larger pore sizes. This results in the loss of mechanical strength and higher expansion values. Under ambient water curing, precipitation and distribution of gelatinous calcium silicate hydrates into the finer network causes a homogeneous morphology and the development of smaller pores. The resultant higher mechanical strength associated with partial hydration of MgO yields reduced expansion. High MgO cement paste containing fly ash also showed considerable pore refinement and improved hydrate morphology favoring volume stability under both autoclave and ambient water curing.

  3. High pressure processing alters water distribution enabling the production of reduced-fat and reduced-salt pork sausages.

    PubMed

    Yang, Huijuan; Han, Minyi; Bai, Yun; Han, Yanqing; Xu, Xinglian; Zhou, Guanghong

    2015-04-01

    High pressure processing (HPP) was used to explore novel methods for modifying the textural properties of pork sausages with reduced-salt, reduced-fat and no fat replacement additions. A 2×7 factorial design was set up, incorporating two pressure levels (0.1 or 200 MPa) and seven fat levels (0, 5, 10, 15, 20, 25 and 30%). Sausages treated at 200 MPa exhibited improved tenderness at all fat levels compared with 0.1 MPa treated samples, and the shear force of sausages treated at 200 MPa with 15 or 20% fat content was similar to the 0.1 MPa treated sausages with 30% fat. HPP significantly changed the P₂ peak ratio of the four water components in raw sausages, resulting in improved textural properties of emulsion-type sausages with reduced-fat and reduced-salt. Significant correlations were found between pH, color, shear force and water proportions. The scanning and transmission micrographs revealed the formation of smaller fat globules and an improved network structure in the pressure treated sausages. In conclusion, there is potential to manufacture sausages with reduced-fat and reduced-salt by using HPP to maintain textural qualities. Copyright © 2014. Published by Elsevier Ltd.

  4. High opportunity for postcopulatory sexual selection under field conditions.

    PubMed

    Turnell, Biz R; Shaw, Kerry L

    2015-08-01

    In polygamous systems, male fitness is determined not only by mating success but also by fertilization success. Despite the growing interest over the past several decades in postcopulatory sexual selection, its relative importance compared to precopulatory sexual selection remains a subject of debate. Here, we use extensive behavioral observations of a seminatural population of Hawaiian swordtail crickets, Laupala cerasina, and molecular paternity assignment to measure the opportunities for pre- and postcopulatory selection. Because postcopulatory selection has the potential to operate at multiple stages, we also separately attribute its effects to factors specific to mating events versus factors specific to males. We find that variance in postcopulatory success is over four times as great as variance in precopulatory success, with most of it unexplained by male mating order or the number of nuptial gifts given. Surprisingly, we also find that male singing effort is under postcopulatory selection, suggesting that males who sing more frequently also have more competitive ejaculates. Our results are consistent with the hypothesis that high polyandry levels promote greater relative postcopulatory selection. They also highlight the need for detailed behavioral observations under conditions as natural as possible when measuring mating and reproductive success.

  5. Bidirectional microbial electron transfer: Switching an acetate oxidizing biofilm to nitrate reducing conditions.

    PubMed

    Pous, Narcís; Carmona-Martínez, Alessandro A; Vilajeliu-Pons, Anna; Fiset, Erika; Bañeras, Lluis; Trably, Eric; Balaguer, M Dolors; Colprim, Jesús; Bernet, Nicolas; Puig, Sebastià

    2016-01-15

    Up to date a few electroactive bacteria embedded in biofilms are described to catalyze both anodic and cathodic reactions in bioelectrochemical systems (i.e. bidirectional electron transfer). How these bacteria transfer electrons to or from the electrode is still uncertain. In this study the extracellular electron transfer mechanism of bacteria within an electroactive biofilm was investigated by using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). First, a mature anodic electroactive biofilm was developed from an activated sludge sample (inoculum), acetate as electron donor and a poised electrode (+397mV vs. SHE). Later, this biofilm was "switched" to biocathodic conditions by feeding it with a medium containing nitrates and poising the electrode at -303mV vs. SHE. The electrochemical characterization indicated that both, acetate oxidation and nitrate reduction took place at a similar formal potential of -175±05 and -175±34mV vs. SHE, respectively. The biofilm was predominantly composed by Geobacter sp. at both experimental conditions. Taken together, the results indicated that both processes could be catalyzed by using the same electron conduit, and most likely by the same bacterial consortium. Hence, this study suggests that electroactive bacteria within biofilms could use the same electron transfer conduit for catalyzing anodic and cathodic reactions. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Anaerobic degradation of toluene and xylene by aquifer microorganisms under sulfate-reducing conditions.

    PubMed Central

    Edwards, E A; Wills, L E; Reinhard, M; Grbić-Galić, D

    1992-01-01

    Toluene and the three isomers of xylene were completely mineralized to CO2 and biomass by aquifer-derived microorganisms under strictly anaerobic conditions. The source of the inoculum was gasoline-contaminated sediment from Seal Beach, Calif. Evidence confirming that sulfate was the terminal electron acceptor is presented. Benzene and ethylbenzene were not degraded under the experimental conditions used. Successive transfers of the mixed cultures that were enriched from aquifer sediments retained the ability to degrade toluene and xylenes. Greater than 90% of 14C-labeled toluene or 14C-labeled o-xylene was mineralized to 14CO2. The doubling time for the culture grown on toluene or m-xylene was about 20 days, and the cell yield was about 0.1 to 0.14 g of cells (dry weight) per g of substrate. The accumulation of sulfide in the cultures as a result of sulfate reduction appeared to inhibit degradation of aromatic hydrocarbons. PMID:1575482

  7. A telehealth nursing intervention reduces hospitalizations in children with complex health conditions.

    PubMed

    Cady, Rhonda; Finkelstein, Stanley; Kelly, Anne

    2009-01-01

    The U Special Kids Program (USK) at the University of Minnesota provides care coordination and case management services by telephone to children with special health-care needs. We measured the effect of the USK programme on hospital resource utilization using a retrospective record review. Information on hospitalizations was collected for children enrolled in the programme for at least two years and validated for accuracy against inpatient claims data. Hospitalizations were classified as planned, unplanned or due to lack of home care. A total of 43 children enrolled in the USK programme between July 1996 and December 2006 met the study criteria. The children had multiple, complex conditions. During the period of the study, there were 61 planned hospitalizations, 184 unplanned hospitalizations and 3 hospitalizations due to lack of home care. The number of unplanned hospitalizations decreased from 74 in the first year of enrolment to 35 in the second; this reduction was significant (P < 0.007). In the subsequent years, the rate of unplanned admissions stabilized. In contrast, the rate of planned hospitalizations was relatively constant over the five-year enrolment period. Telephone-based care coordination and case management is a promising approach for children with multiple, complex health conditions.

  8. Neuregulin 1 Transgenic Mice Display Reduced Mismatch Negativity, Contextual Fear Conditioning and Social Interactions

    PubMed Central

    Ehrlichman, Richard S.; Luminais, Steven N.; White, Samantha L.; Rudnick, Noam D.; Ma, Nan; Dow, Holly C.; Kreibich, Arati S.; Abel, Ted; Brodkin, Edward S.; Hahn, Chang-Gyu; Siegel, Steven J.

    2009-01-01

    Introduction Neuregulin-1 (NRG1) is one of susceptibility genes for schizophrenia and plays critical roles in glutamatergic, dopaminergic and GABAergic signaling. Using mutant mice heterozygous for Nrg1 (Nrg1+/−) we studied the effects of Nrg1 signaling on behavioral and electrophysiological measures relevant to schizophrenia. Experimental Procedure Behavior of Nrg1+/− mice and their wild type littermates was evaluated using pre-pulse inhibition, contextual fear conditioning, novel object recognition, locomotor, and social choice paradigms. Event-related potentials (ERPs) were recorded to assess auditory gating and novel stimulus detection. Results Gating of ERPs was unaffected in Nrg1+/− mice, but mismatch negativity in response to novel stimuli was attenuated. The Nrg1+/− mice exhibited behavioral deficits in contextual fear conditioning and social interactions, while locomotor activity, pre-pulse inhibition and novel object recognition were not impaired. Summary Nrg1+/− mice had impairments in a subset of behavioral and electrophysiological tasks relevant to the negative/cognitive symptom domains of schizophrenia that are thought to be influenced by glutamatergic and dopaminergic neurotransmission. These mice are a valuable tool for studying endophenotypes of schizophrenia, but highlight that single genes can not account for the complex pathophysiology of the disorder. PMID:19643092

  9. WSe2-contact metal interface chemistry and band alignment under high vacuum and ultra high vacuum deposition conditions

    NASA Astrophysics Data System (ADS)

    Smyth, Christopher M.; Addou, Rafik; McDonnell, Stephen; Hinkle, Christopher L.; Wallace, Robert M.

    2017-06-01

    Contact metals (Au, Ir, and Cr) are deposited on bulk WSe2 under ultra-high vacuum (UHV, 1  ×  10-9 mbar) and high vacuum (HV, 5  ×  10-6 mbar) conditions and subsequently characterized with x-ray photoelectron spectroscopy (XPS) to elucidate the effects of reactor base pressure on resulting interface chemistry, contact chemistry, and band alignment. Au forms a van der Waals interface with WSe2 regardless of deposition chamber ambient. In contrast, Ir and Cr form a covalent interface by reducing WSe2 to form interfacial metal selenides. When Cr is deposited under HV conditions, significant oxygen incorporation is observed resulting in the thermodynamically favorable formation of tungsten oxyselenide and a substantial concentration of Cr x O y . Regardless of contact metal, WO x (2.63  <  x  <  2.92) forms during deposition under HV conditions which may positively affect interface transport properties. Cr and Ir form unexpectedly large electron and hole Schottky barriers, respectively, when deposited under UHV conditions due to interfacial reactions that contribute to anomalous band alignment. These results reveal the true interface chemistry formed between metals and WSe2 under UHV and HV conditions and demonstrate the impact on the Fermi level position following contact formation on WSe2.

  10. Mass Transport Phenomena Between Bubbles and Dissolved Gases in Liquids Under Reduced Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Dewitt, K. J.; Brockwell, J. L.

    1985-01-01

    The long term objective of the experiment is to observe the dissolution of isolated, immobile gas bubbles of specified size and composition in a solvent liquid of known concentration in the reduced gravity environment of earth orbit. Preliminary bubble dissolution experiment conducted both in the NASA Lewis 2.2 sec drop tower and in normal gravity using SO2 - Toluene system were not completely successful in their objective. The method of gas injection and lack of bubble interface stabiliy experienced due to the extreme solubility of SO in Toluene has the effects of changing the problem from that of bubble dissolution to one of bubble formation stability and subsequent dissolution in a liquid of unknown initial solute concentration. Current work involves further experimentation in order to refine the bubble injection system and to investigate the concept of having a bubble with a critical radius in a state of unstable equilibrium.

  11. Mass Transport Phenomena Between Bubbles and Dissolved Gases in Liquids Under Reduced Gravity Conditions

    NASA Technical Reports Server (NTRS)

    Dewitt, K. J.; Brockwell, J. L.

    1985-01-01

    The long term objective of the experiment is to observe the dissolution of isolated, immobile gas bubbles of specified size and composition in a solvent liquid of known concentration in the reduced gravity environment of earth orbit. Preliminary bubble dissolution experiment conducted both in the NASA Lewis 2.2 sec drop tower and in normal gravity using SO2 - Toluene system were not completely successful in their objective. The method of gas injection and lack of bubble interface stabiliy experienced due to the extreme solubility of SO in Toluene has the effects of changing the problem from that of bubble dissolution to one of bubble formation stability and subsequent dissolution in a liquid of unknown initial solute concentration. Current work involves further experimentation in order to refine the bubble injection system and to investigate the concept of having a bubble with a critical radius in a state of unstable equilibrium.

  12. Behavior of Self-Lubricated Liquids Under Normal and Reduced-Pressure Conditions

    NASA Astrophysics Data System (ADS)

    dell'Aversana, P.; Tontodonato, V.; Neitzel, G. P.

    1999-11-01

    We explore the behavior of liquid systems where wetting is inhibited via a (self) lubrication effect produced by thermocapillary convection. We investigate shape changes in the lubricating air film when the ambient air pressure is reduced to determine the effect on load capacity and, ultimately, reliability of a system exploiting this effect. We examine the response to electrostatic charges that may induce the wetting of a solid surface, even when the lubricating action of the air film would be sufficient to prevent it otherwise. We have observed that a static model is suitable for describing the behavior of such systems despite the existence of convection. An original technique for measuring the difference between advancing and receding contact angles of a silicone oil drop attached at a copper platelet is presented. The drop is first squeezed and then released by an unwetted glass surface loaded onto the drop. Again, the static model seems suitable to describe the mechanical behavior of such a system.

  13. Delivery and Payment Redesign to Reduce Disparities in High Risk Postpartum Care.

    PubMed

    Howell, Elizabeth A; Padrón, Norma A; Beane, Susan J; Stone, Joanne; Walther, Virginia; Balbierz, Amy; Kumar, Rashi; Pagán, José A

    2017-03-01

    Purpose This paper describes the implementation of an innovative program that aims to improve postpartum care through a set of coordinated delivery and payment system changes designed to use postpartum care as an opportunity to impact the current and future health of vulnerable women and reduce disparities in health outcomes among minority women. Description A large health care system, a Medicaid managed care organization, and a multidisciplinary team of experts in obstetrics, health economics, and health disparities designed an intervention to improve postpartum care for women identified as high-risk. The program includes a social work/care management component and a payment system redesign with a cost-sharing arrangement between the health system and the Medicaid managed care plan to cover the cost of staff, clinician education, performance feedback, and clinic/clinician financial incentives. The goal is to enroll 510 high-risk postpartum mothers. Assessment The primary outcome of interest is a timely postpartum visit in accordance with NCQA healthcare effectiveness data and information set guidelines. Secondary outcomes include care process measures for women with specific high-risk conditions, emergency room visits, postpartum readmissions, depression screens, and health care costs. Conclusion Our evidence-based program focuses on an important area of maternal health, targets racial/ethnic disparities in postpartum care, utilizes an innovative payment reform strategy, and brings together insurers, researchers, clinicians, and policy experts to work together to foster health and wellness for postpartum women and reduce disparities.

  14. Reduced ability to detect surface-related biofilm bacteria after antibiotic exposure under in vitro conditions.

    PubMed

    Ravn, Christen; Furustrand Tafin, Ulrika; Bétrisey, Bertrand; Overgaard, Søren; Trampuz, Andrej

    2016-12-01

    Background and purpose - Antibiotic treatment of patients before specimen collection reduces the ability to detect organisms by culture. We investigated the suppressive effect of antibiotics on the growth of non-adherent, planktonic, and surface-related biofilm bacteria in vitro by using sonication and microcalorimetry methods. Patients and methods - Biofilms of Staphylococcus aureus, S. epidermidis, Escherichia coli, and Propionibacterium acnes were formed on porous glass beads and exposed for 24 h to antibiotic concentrations from 1 to 1,024 times the minimal inhibitory concentration (MIC) of vancomycin, daptomycin, rifampin, flucloxacillin, or ciprofloxacin. The beads were then sonicated to dislodge biofilm, followed by culture and measurement of growth-related heat flow by microcalorimetry of the resulting sonication fluid. Results - Vancomycin did not inhibit the heat flow of staphylococci and P. acnes at concentrations ≤1,024 μg/mL, whereas flucloxacillin at >128 μg/mL inhibited S. aureus. Daptomycin inhibited heat flow of S. aureus, S. epidermidis, and P. acnes at lower concentrations (32-128 times MIC, p < 0.001). Rifampin showed inconsistent results in staphylococci due to random emergence of resistance, which was observed at concentrations ≤1,024 times MIC (i.e. 8 μg/mL). Ciprofloxacin inhibited heat flow of E. coli at ≥4 times MIC (i.e. ≥ 0.06 μg/mL). Interpretation - Whereas time-dependent antibiotics (i.e. vancomycin and flucloxacillin) showed only weak growth suppression, concentration-dependent drugs (i.e. daptomycin and ciprofloxacin) had a strong suppressive effect on bacterial growth and reduced the ability to detect planktonic and biofilm bacteria. Exposure to rifampin rapidly caused emergence of resistance. Our findings indicate that preoperative administration of antibiotics may have heterogeneous effects on the ability to detect biofilm bacteria.

  15. Reduced ability to detect surface-related biofilm bacteria after antibiotic exposure under in vitro conditions

    PubMed Central

    Ravn, Christen; Furustrand Tafin, Ulrika; Bétrisey, Bertrand; Overgaard, Søren; Trampuz, Andrej

    2016-01-01

    Background and purpose Antibiotic treatment of patients before specimen collection reduces the ability to detect organisms by culture. We investigated the suppressive effect of antibiotics on the growth of non-adherent, planktonic, and surface-related biofilm bacteria in vitro by using sonication and microcalorimetry methods. Patients and methods Biofilms of Staphylococcus aureus, S. epidermidis, Escherichia coli, and Propionibacterium acnes were formed on porous glass beads and exposed for 24 h to antibiotic concentrations from 1 to 1,024 times the minimal inhibitory concentration (MIC) of vancomycin, daptomycin, rifampin, flucloxacillin, or ciprofloxacin. The beads were then sonicated to dislodge biofilm, followed by culture and measurement of growth-related heat flow by microcalorimetry of the resulting sonication fluid. Results Vancomycin did not inhibit the heat flow of staphylococci and P. acnes at concentrations ≤1,024 μg/mL, whereas flucloxacillin at >128 μg/mL inhibited S. aureus. Daptomycin inhibited heat flow of S. aureus, S. epidermidis, and P. acnes at lower concentrations (32–128 times MIC, p < 0.001). Rifampin showed inconsistent results in staphylococci due to random emergence of resistance, which was observed at concentrations ≤1,024 times MIC (i.e. 8 μg/mL). Ciprofloxacin inhibited heat flow of E. coli at ≥4 times MIC (i.e. ≥ 0.06 μg/mL). Interpretation Whereas time-dependent antibiotics (i.e. vancomycin and flucloxacillin) showed only weak growth suppression, concentration-dependent drugs (i.e. daptomycin and ciprofloxacin) had a strong suppressive effect on bacterial growth and reduced the ability to detect planktonic and biofilm bacteria. Exposure to rifampin rapidly caused emergence of resistance. Our findings indicate that preoperative administration of antibiotics may have heterogeneous effects on the ability to detect biofilm bacteria. PMID:27775462

  16. The metabolic costs of improving ethanol yield by reducing glycerol formation capacity under anaerobic conditions in Saccharomyces cerevisiae

    PubMed Central

    2013-01-01

    Background Finely regulating the carbon flux through the glycerol pathway by regulating the expression of the rate controlling enzyme, glycerol-3-phosphate dehydrogenase (GPDH), has been a promising approach to redirect carbon from glycerol to ethanol and thereby increasing the ethanol yield in ethanol production. Here, strains engineered in the promoter of GPD1 and deleted in GPD2 were used to investigate the possibility of reducing glycerol production of Saccharomyces cerevisiae without jeopardising its ability to cope with process stress during ethanol production. For this purpose, the mutant strains TEFmut7 and TEFmut2 with different GPD1 residual expression were studied in Very High Ethanol Performance (VHEP) fed-batch process under anaerobic conditions. Results Both strains showed a drastic reduction of the glycerol yield by 44 and 61% while the ethanol yield improved by 2 and 7% respectively. TEFmut2 strain showing the highest ethanol yield was accompanied by a 28% reduction of the biomass yield. The modulation of the glycerol formation led to profound redox and energetic changes resulting in a reduction of the ATP yield (YATP) and a modulation of the production of organic acids (acetate, pyruvate and succinate). Those metabolic rearrangements resulted in a loss of ethanol and stress tolerance of the mutants, contrarily to what was previously observed under aerobiosis. Conclusions This work demonstrates the potential of fine-tuned pathway engineering, particularly when a compromise has to be found between high product yield on one hand and acceptable growth, productivity and stress resistance on the other hand. Previous study showed that, contrarily to anaerobiosis, the resulting gain in ethanol yield was accompanied with no loss of ethanol tolerance under aerobiosis. Moreover those mutants were still able to produce up to 90 gl-1 ethanol in an anaerobic SSF process. Fine tuning metabolic strategy may then open encouraging possibilities for further

  17. Experimental Study on the pH of Pore water in Compacted Bentonite under Reducing Conditions with Electromigration

    SciTech Connect

    Nessa, S.A.; Idemitsu, K.; Yamazaki, S.; Ikeuchi, H.; Inagaki, Y.; Arima, T.

    2008-07-01

    Compacted bentonite and carbon steel are considered a good buffer and over-pack materials in the repositories of high-level radioactive waste disposal. Sodium bentonite, Kunipia-F contains approximately 95 wt% of montmorillonite. Bentonites prominent properties of high swelling, sealing ability and cation exchange capacity provide retardation against the transport of radionuclides from the waste into the surrounding rocks in the repository and its properties determine the behavior of bentonite. In this regards, the pH of pore water in compacted bentonite is measured with pH test paper wrapped with semi-permeable membrane of collodion sheet under reducing conditions. On 30 days, the pH test paper in the experimental apparatus indicated that the pH of pore water in compacted bentonite is around 8.0 at saturated state. The carbon steel coupon is connected as the working electrode to the potentiostat and is held at a constant supplied potential between +300 and -300 mV vs. Ag/AgCl electrode for up to 7 days. During applying electromigration the pH of pore water in bentonite decreased and it reached 6.0{approx}6.0 on 7 days. The concentration of iron and sodium showed nearly complementary distribution in the bentonite specimen after electromigration. It is expected that iron could migrate as ferrous ion through the interlayer of montmorillonite replacing exchangeable sodium ions in the interlayer. Semi-permeable membrane of collodion sheet does not affect the color change of pH test paper during the experiment. (authors)

  18. Isolation, identification and characterization of highly tellurite-resistant, tellurite-reducing bacteria from Antarctica

    NASA Astrophysics Data System (ADS)

    Arenas, Felipe A.; Pugin, Benoit; Henríquez, Nicole A.; Arenas-Salinas, Mauricio A.; Díaz-Vásquez, Waldo A.; Pozo, María F.; Muñoz, Claudia M.; Chasteen, Thomas G.; Pérez-Donoso, José M.; Vásquez, Claudio C.

    2014-03-01

    The tellurium oxyanion, tellurite, is extremely noxious to most living organisms. Its toxicity has been mainly related to the generation of reactive oxygen species (ROS) as well as to an unbalancing of the thiol:redox buffering system. Nevertheless, a few bacteria are capable of thriving at high tellurite concentrations. One mechanism of resistance is the enzymatic and non-enzymatic reduction of tellurite to the less toxic elemental tellurium. This reduction generates nano- to micrometric tellurium crystals that display different shapes and sizes. To date, a very limited number of highly tellurite-resistant and tellurite-reducing bacterial species are available from international culture collections. In this work, we decided to look for tellurite-reducing bacteria from an extreme environment, Antarctica. This environment exhibits a combination of several extreme factors such as high UV-radiation and desiccation and freezing conditions that impact directly on the local biodiversity. Since, as does, all these factors induce ROS formation, we hypothesized that Antarctic bacteria could also exhibit tellurite-resistance. In this context, we isolated 123 tellurite-resistant bacteria, and characterized six new tellurite-resistant and tellurite-reducing bacterial strains from samples collected in Antarctica. These strains were identified according to their 16S rRNA gene sequence as Staphylococcus hameolyticus, Staphylococcus sciuri, Acinetobacter haemolyticus, Pseudomonas lini, and two strains of Psychrobacter immobilis. The isolates display tellurite-resistance about 35- to 500-fold higher than Escherichia coli (Te-sensitive organism), and a high level of tellurite reduction which might be interesting for an application in the field of bioremediation or nanoparticle biosynthesis.

  19. Appetitive sensitization by amphetamine does not reduce its ability to produce conditioned taste aversion to saccharin.

    PubMed

    Scott-Railton, John; Arnold, Gretchen; Vezina, Paul

    2006-12-15

    Previous exposure to amphetamine attenuates its ability to induce conditioned taste aversion (CTA). Because amphetamine, unlike emetic agents like LiCl, possesses appetitive properties that sensitize when it is administered repeatedly, the present study assessed the contribution of sensitization to this US-pre-exposure effect (US-PEE). It was found that not all sensitizing regimens of systemic amphetamine injections produce a US-PEE. In addition, previous exposure to amphetamine in the VTA, where it acts to induce sensitization but not CTA, did not produce a US-PEE. It is concluded that amphetamine sensitization alone does not modulate this drug's ability to produce CTA. Implications of these findings for anatomically based associative and non-associative models of CTA and the US-PEE are discussed.

  20. System and method of providing quick thermal comfort with reduced energy by using directed spot conditioning

    DOEpatents

    Wang, Mingyu; Kadle, Prasad S.; Ghosh, Debashis; Zima, Mark J.; Wolfe, IV, Edward; Craig, Timothy D

    2016-10-04

    A heating, ventilation, and air conditioning (HVAC) system and a method of controlling a HVAC system that is configured to provide a perceived comfortable ambient environment to an occupant seated in a vehicle cabin. The system includes a nozzle configured to direct an air stream from the HVAC system to the location of a thermally sensitive portion of the body of the occupant. The system also includes a controller configured to determine an air stream temperature and an air stream flow rate necessary to establish the desired heat supply rate for the sensitive portion and provide a comfortable thermal environment by thermally isolating the occupant from the ambient vehicle cabin temperature. The system may include a sensor to determine the location of the sensitive portion. The nozzle may include a thermoelectric device to heat or cool the air stream.

  1. Reducing Conservatism in Aircraft Engine Response Using Conditionally Active Min-Max Limit Regulators

    NASA Technical Reports Server (NTRS)

    May, Ryan D.; Garg, Sanjay

    2012-01-01

    Current aircraft engine control logic uses a Min-Max control selection structure to prevent the engine from exceeding any safety or operational limits during transients due to throttle commands. This structure is inherently conservative and produces transient responses that are slower than necessary. In order to utilize the existing safety margins more effectively, a modification to this architecture is proposed, referred to as a Conditionally Active (CA) limit regulator. This concept uses the existing Min-Max architecture with the modification that limit regulators are active only when the operating point is close to a particular limit. This paper explores the use of CA limit regulators using a publicly available commercial aircraft engine simulation. The improvement in thrust response while maintaining all necessary safety limits is demonstrated in a number of cases.

  2. Bubble Stripping as a Tool To Reduce High Dissolved CO2 in Coastal Marine Ecosystems.

    PubMed

    Koweek, David A; Mucciarone, David A; Dunbar, Robert B

    2016-04-05

    High dissolved CO2 concentrations in coastal ecosystems are a common occurrence due to a combination of large ecosystem metabolism, shallow water, and long residence times. Many important coastal species may have adapted to this natural variability over time, but eutrophication and ocean acidification may be perturbing the water chemistry beyond the bounds of tolerance for these organisms. We are currently limited in our ability to deal with the geochemical changes unfolding in our coastal ocean. This study helps to address this deficit of solutions by introducing bubble stripping as a novel geochemical engineering approach to reducing high CO2 in coastal marine ecosystems. We use a process-based model to find that air/sea gas exchange rates within a bubbled system are 1-2 orders of magnitude higher than within a nonbubbled system. By coupling bubbling-enhanced ventilation to a coastal ecosystem metabolism model, we demonstrate that strategically timed bubble plumes can mitigate exposure to high CO2 under present-day conditions and that exposure mitigation is enhanced in the more acidic conditions predicted by the end of the century. We argue that shallow water CO2 bubble stripping should be considered among the growing list of engineering approaches intended to increase coastal resilience in a changing ocean.

  3. Conditional Sox9 ablation reduces chondroitin sulfate proteoglycan levels and improves motor function following spinal cord injury.

    PubMed

    McKillop, William M; Dragan, Magdalena; Schedl, Andreas; Brown, Arthur

    2013-02-01

    Chondroitin sulfate proteoglycans (CSPGs) found in perineuronal nets and in the glial scar after spinal cord injury have been shown to inhibit axonal growth and plasticity. Since we have previously identified SOX9 as a transcription factor that upregulates the expression of a battery of genes associated with glial scar formation in primary astrocyte cultures, we predicted that conditional Sox9 ablation would result in reduced CSPG expression after spinal cord injury and that this would lead to increased neuroplasticity and improved locomotor recovery. Control and Sox9 conditional knock-out mice were subject to a 70 kdyne contusion spinal cord injury at thoracic level 9. One week after injury, Sox9 conditional knock-out mice expressed