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Sample records for altered charge selectivity

  1. Charged anaesthetics alter LM-fibroblast plasma-membrane enzymes by selective fluidization of inner or outer membrane leaflets.

    Science.gov (United States)

    Sweet, W D; Schroeder, F

    1986-10-15

    The functional consequences of the differences in lipid composition and structure between the two leaflets of the plasma membrane were investigated. Fluorescence of 1,6-diphenylhexa-1,3,5-triene(DPH), quenching, and differential polarized phase fluorimetry demonstrated selective fluidization by local anaesthetics of individual leaflets in isolated LM-cell plasma membranes. As measured by decreased limiting anisotropy of DPH fluorescence, cationic (prilocaine) and anionic (phenobarbital and pentobarbital) amphipaths preferentially fluidized the cytofacial and exofacial leaflets respectively. Unlike prilocaine, procaine, also a cation, fluidized both leaflets of these membranes equally. Pentobarbital stimulated 5'-nucleotidase between 0.1 and 5 mM and inhibited at higher concentrations, whereas phenobarbital only inhibited, at higher concentrations. Cationic drugs were ineffective. Two maxima of (Na+ + K+)-ATPase activation were obtained with both anionic drugs. Only one activation maximum was obtained with both cationic drugs. The maximum in activity below 1 mM for all four drugs clustered about a single limiting anisotropy value in the cytofacial leaflet, whereas there was no correlation between activity and limiting anisotropy in the exofacial leaflets. Therefore, although phenobarbital and pentobarbital below 1 mM fluidized the exofacial leaflet more than the cytofacial leaflet, the smaller fluidization in the cytofacial leaflet was functionally significant for (Na+ + K+)-ATPase. Mg2+-ATPase was stimulated at 1 mM-phenobarbital, unaffected by pentobarbital and slightly stimulated by both cationic drugs at concentrations fluidizing both leaflets. Thus the activity of (Na+ + K+)-ATPase was highly sensitive to selective fluidization of the leaflet containing its active site, whereas the other enzymes examined were little affected by fluidization of either leaflet.

  2. The Selection of the Phone Charging IC

    Institute of Scientific and Technical Information of China (English)

    Jian ming Lei

    2013-01-01

    An expensive digital IC is used in old battery only charger (BOC) and this IC needs separate software. For simplify the design and reduce the cost, we find the existing analogy charging ICs and select the most popular four from them, including Mitsumi, Freescale, TI and Analogic Tech, we make a detailed comparison and select the best one, based on this IC’s feature and our requirements, A detailed design evaluation is presented, including the design of the input over voltage protection (OVP), output OVP and over temperature protection (OTP), the WCA (Worse Case Analysis) of this OTP. After the improvement, this new BOC has lower cost, simpler topology, more efficient power consumption.

  3. Streamflow alteration at selected sites in Kansas

    Science.gov (United States)

    Juracek, Kyle E.; Eng, Ken

    2017-06-26

    An understanding of streamflow alteration in response to various disturbances is necessary for the effective management of stream habitat for a variety of species in Kansas. Streamflow alteration can have negative ecological effects. Using a modeling approach, streamflow alteration was assessed for 129 selected U.S. Geological Survey streamgages in the State for which requisite streamflow and basin-characteristic information was available. The assessment involved a comparison of the observed condition from 1980 to 2015 with the predicted expected (least-disturbed) condition for 29 streamflow metrics. The metrics represent various characteristics of streamflow including average flow (annual, monthly) and low and high flow (frequency, duration, magnitude).Streamflow alteration in Kansas was indicated locally, regionally, and statewide. Given the absence of a pronounced trend in annual precipitation in Kansas, a precipitation-related explanation for streamflow alteration was not supported. Thus, the likely explanation for streamflow alteration was human activity. Locally, a flashier flow regime (typified by shorter lag times and more frequent and higher peak discharges) was indicated for three streamgages with urbanized basins that had higher percentages of impervious surfaces than other basins in the State. The combination of localized reservoir effects and regional groundwater pumping from the High Plains aquifer likely was responsible, in part, for diminished conditions indicated for multiple streamflow metrics in western and central Kansas. Statewide, the implementation of agricultural land-management practices to reduce runoff may have been responsible, in part, for a diminished duration and magnitude of high flows. In central and eastern Kansas, implemented agricultural land-management practices may have been partly responsible for an inflated magnitude of low flows at several sites.

  4. Methylphenidate alters selective attention by amplifying salience

    NARCIS (Netherlands)

    Huurne, N.; Fallon, S.J.; Schouwenburg, M. van; Schaaf, M.; Buitelaar, J.; Jensen, O.; Cools, R.

    2015-01-01

    RATIONALE: Methylphenidate, the most common treatment of attention deficit hyperactivity disorder (ADHD), is increasingly used by healthy individuals as a "smart drug" to enhance cognitive abilities like attention. A key feature of (selective) attention is the ability to ignore irrelevant but salien

  5. Reduced glomerular size- and charge-selectivity in clinically healthy individuals with microalbuminuria

    DEFF Research Database (Denmark)

    Jensen, J S; Borch-Johnsen, K; Deckert, T

    1995-01-01

    The pathophysiologic mechanism behind microalbuminuria, a potential atherosclerotic risk factor, was explored by measuring fractional clearances of four endogenous plasma proteins of different size and electric charge (albumin, beta 2-microglobulin, immunoglobulin G, and immunoglobulin G4). Twenty......-microglobulin clearance was similar in the two groups. Since total IgG and the IgG4 subclass are of similar size and configuration but electrically neutral and negative, respectively; these findings indicate that microalbuminuria is associated with decreased size- and charge-selectivity of the glomerular vessel...... wall. Hypothetically, such alterations may reflect generalized vascular abnormalities linking microalbuminuria to atherogenesis....

  6. Low-energy state-selective charge transfer by multiply charged ions

    NARCIS (Netherlands)

    Lubinski, G; Juhasz, Z; Morgenstern, R; Hoekstra, R

    2001-01-01

    We present a combined rf-guided ion beam and photon emission spectroscopy method, which facilitates state-selective charge-transfer measurements at energies of direct relevance for astrophysics and fusion-plasma diagnostics and modeling. Ion energies have been varied from 1000 eV/amu down to energie

  7. Alterations of CNS structure & function by charged particle radiation & resultant oxidative stress

    Science.gov (United States)

    Nelson, Gregory; Chang, Polly; Favre, Cecile; Fike, John; Komarova, Natalia; Limoli, Charles; Mao, Xiao-Wen; Obenaus, Andre; Raber, Jacob; Spigelman, Igor; Soltesz, Ivan; Song, Sheng-Kwei; Stampanoni, Marco; Vlkolinsky, Roman; Wodarz, Dominik

    were complex and suggested continuous remodeling of the brain for up to 6 months. Thus we demonstrated a suite of CNS structural and functional changes after proton and iron ion exposure in the low dose regime. Based on these findings we will now test whether oxidative stress mediates the reactions of CNS to radiation exposure and what role radiation quality and dose rate play in the responses. We will use cultured neural precursor cells (mouse human) to detect changes in oxidative status and differentiation as functions of charged particle charge and velocity. These results will inform the selection of particles for many in vivo measurements that will compare wild type mice to a transgenic strain that over-expresses a human catalase gene (which inactivates hydrogen peroxide) in the mitochondrial compartment. This will explicitly test the role of reactive oxygen species in mediating the mechanisms underlying the CNS endpoints that we will measure. We will extend the electrophysiological measurements on individual nerves in hippocampal slices to characterize both inhibitory and excitatory synapses. Further, multi-electrode arrays will be used to follow correlated electrical activity in different hippocampal regions in order to understand network-level function as well as synaptic efficacy and plasticity. Controlled oxidative stress on irradiated samples will explore whether response mechanisms are shared. To link alterations in neurogenesis to performance we will explore behavioral changes mediated by the hippocampus simultaneously with measures of expression of the Arc gene in newly-born neurons. This will test whether decrements in performance correlate with loss of new cells and whether behavior properly stimulates functional integration of the new cells; the behavioral paradigm will be contextual fear conditioning. We will develop mathematical frameworks for CNS responses to radiation in order to inform risk estimates. Finally, we will couple a high

  8. Charge transport-driven selective oxidation of graphene

    Science.gov (United States)

    Lee, Young Keun; Choi, Hongkyw; Lee, Changhwan; Lee, Hyunsoo; Goddeti, Kalyan C.; Moon, Song Yi; Doh, Won Hui; Baik, Jaeyoon; Kim, Jin-Soo; Choi, Jin Sik; Choi, Choon-Gi; Park, Jeong Young

    2016-06-01

    Due to the tunability of the physical, electrical, and optical characteristics of graphene, precisely controlling graphene oxidation is of great importance for potential applications of graphene-based electronics. Here, we demonstrate a facile and precise way for graphene oxidation controlled by photoexcited charge transfer depending on the substrate and bias voltage. It is observed that graphene on TiO2 is easily oxidized under UV-ozone treatment, while graphene on SiO2 remains unchanged. The mechanism for the selective oxidation of graphene on TiO2 is associated with charge transfer from the TiO2 to the graphene. Raman spectra were used to investigate the graphene following applied bias voltages on the graphene/TiO2 diode under UV-ozone exposure. We found that under a reverse bias of 0.6 V on the graphene/TiO2 diode, graphene oxidation was accelerated under UV-ozone exposure, thus confirming the role of charge transfer between the graphene and the TiO2 that results in the selective oxidation of the graphene. The selective oxidation of graphene can be utilized for the precise, nanoscale patterning of the graphene oxide and locally patterned chemical doping, finally leading to the feasibility and expansion of a variety of graphene-based applications.Due to the tunability of the physical, electrical, and optical characteristics of graphene, precisely controlling graphene oxidation is of great importance for potential applications of graphene-based electronics. Here, we demonstrate a facile and precise way for graphene oxidation controlled by photoexcited charge transfer depending on the substrate and bias voltage. It is observed that graphene on TiO2 is easily oxidized under UV-ozone treatment, while graphene on SiO2 remains unchanged. The mechanism for the selective oxidation of graphene on TiO2 is associated with charge transfer from the TiO2 to the graphene. Raman spectra were used to investigate the graphene following applied bias voltages on the graphene/TiO2

  9. Electrokinetic Instability near Charge-Selective Hydrophobic Surfaces

    CERN Document Server

    Shelistov, V S; Ganchenko, G S

    2014-01-01

    The influence of the texture of a hydrophobic surface on the electro-osmotic slip of the second kind and the electrokinetic instability near charge-selective surfaces (permselective membranes, electrodes, or systems of micro- and nanochannels) is investigated theoretically using a simple model based on the Rubinstein-Zaltzman approach. A simple formula is derived to evaluate the decrease in the instability threshold due to hydrophobicity. The study is complemented by numerical investigations both of linear and nonlinear instabilities near a hydrophobic membrane surface. Theory predicts a significant enhancement of the ion flux to the surface and shows a good qualitative agreement with the available experimental data.

  10. Epigenetic Alterations in Density Selected Human Spermatozoa for Assisted Reproduction.

    Directory of Open Access Journals (Sweden)

    Bolan Yu

    Full Text Available Epidemiological evidence indicates that assisted reproductive technologies (ART may be associated with several epigenetic diseases such as Beckwith-Wiedemann syndrome (BWS or Silver-Russell syndrome (SRS. Selection of sperm by density-gradients in ART has improved DNA integrity and sperm quality; however, epigenetic alterations associated with this approach are largely unknown. In the present study, we investigated DNA methylation and histone retention profiles in raw sperm and selected sperm derived from the same individual and separated by using density-gradients. Results from a study group consisting of 93 males demonstrated that both global DNA methylation and histone retention levels decreased in density selected sperm. Compared to unselected raw sperm, histone transition rates decreased by an average of 27.2% in selected sperm, and the global methylation rate was 3.8% in unselected sperm and 3.3% in the selected sperm. DNA methylation and histone retention location profiling analyses suggested that these alterations displayed specific location patterns in the human genome. Changes in the pattern of hypomethylation largely occurred in transcriptional factor gene families such as HOX, FOX, and GATA. Histone retention increased in 67 genes, whereas it was significantly clustered in neural development-related gene families, particularly the olfactory sensor gene family. Although a causative relationship could not be established, the results of the present study suggest the possibility that sperm with good density also possess unique epigenetic profiles, particularly for genes involved in neural and olfactory development. As increasing evidence demonstrates that epigenetics plays a key role in embryonic development and offspring growth characteristics, the specific epigenetic alterations we observed in selected sperm may influence the transcriptional process and neural development in embryos.

  11. Selective Induced Altered Coccidians to Immunize and Prevent Enteritis

    Science.gov (United States)

    2016-01-01

    Microbiomic flora in digestive tract is pivotal to the state of our health and disease. Antibiotics affect GI, control composition of microbiome, and shift equilibrium from health into disease status. Coccidiosis causes gastrointestinal inflammation. Antibiotic additives contaminate animal products and enter food chain, consumed by humans with possible allergic, antibiotic resistance and enigmatic side effects. Purposed study induced nonpathogenic, immunogenic organisms to protect against disease and abolish antibiotics' use in food animals and side effects in man. Diverse species of Coccidia were used as model. Immature organisms were treated with serial purification procedure prior to developmental stages to obtain altered strains. Chicks received oral gavage immunized with serial low doses of normal or altered organisms or sham treatment and were challenged with high infective normal organisms to compare pathogenicity and immunogenicity. Mature induced altered forms of E. tenella and E. necatrix lacked developmental stage of “sporocysts” and contained free sporozoites. In contrast, E. maxima progressed to normal forms or did not mature at all. Animals that received altered forms were considerably protected with higher weight gain and antibody titers against challenge infection compared to those that received normal organisms (p < 0.05). This is the first report to induce selected protective altered organisms for possible preventive measures to minimize antibiotic use in food animals. PMID:27721824

  12. Effect of alterations in glomerular charge on deposition of cationic and anionic antibodies to fixed glomerular antigens in the rat.

    Science.gov (United States)

    Adler, S; Baker, P; Pritzl, P; Couser, W G

    1985-07-01

    Reduction of the negative charge of the glomerular capillary wall alters its charge- and size-selective properties. To investigate the effect of alteration in glomerular charge properties on antibody localization, we prepared cationic and anionic fractions of antibodies to subepithelial and glomerular basement membrane (GBM) antigens, and compared their deposition in normal rats and rats treated with protamine sulfate or aminonucleoside of puromycin to reduce capillary wall charge. IgG antibodies were eluted from kidneys of rats with active Heymann's nephritis (AICN), passive Heymann's nephritis (PHN), or anti-GBM nephritis (NTN), separated into cationic and anionic fractions, and radiolabeled with iodine 125 or iodine 131. Relative antibody content of each fraction was determined by incubation with an excess of glomerular antigen. Varying amounts of cationic and anionic IgG eluted from kidneys of rats with AICN or PHN were injected into 24 normal or protamine sulfate-treated rats. Glomerular binding of all antibodies was highly correlated with IgG delivery to the kidney. The ratio of cationic to anionic antibody deposited in the glomeruli of normal rats after 4 hours was 1.08 +/- 0.07 for AICN eluate and 0.37 +/- 0.04 for PHN eluate. The ratios were not significantly different in animals pretreated with protamine sulfate (1.15 +/- 0.06 and 0.44 +/- 0.06, respectively; P greater than 0.05). Varying amounts of cationic and anionic IgG eluted from kidneys of rats with NTN were injected into 10 normal rats and four rats treated with aminonucleoside of puromycin. Glomerular binding of antibody was again highly correlated with IgG delivery to the kidney. The ratio of cationic to anionic antibody deposited in the glomeruli of normal rats after 1 hour was 1.03 +/- 0.06, and was not significantly altered in rats treated with aminonucleoside of puromycin (1.05 +/- 0.03, P greater than 0.5). Proteinuria in PHN rats was also unaffected by treatment with protamine sulfate for

  13. Why climate change will invariably alter selection pressures on phenology.

    Science.gov (United States)

    Gienapp, Phillip; Reed, Thomas E; Visser, Marcel E

    2014-10-22

    The seasonal timing of lifecycle events is closely linked to individual fitness and hence, maladaptation in phenological traits may impact population dynamics. However, few studies have analysed whether and why climate change will alter selection pressures and hence possibly induce maladaptation in phenology. To fill this gap, we here use a theoretical modelling approach. In our models, the phenologies of consumer and resource are (potentially) environmentally sensitive and depend on two different but correlated environmental variables. Fitness of the consumer depends on the phenological match with the resource. Because we explicitly model the dependence of the phenologies on environmental variables, we can test how differential (heterogeneous) versus equal (homogeneous) rates of change in the environmental variables affect selection on consumer phenology. As expected, under heterogeneous change, phenotypic plasticity is insufficient and thus selection on consumer phenology arises. However, even homogeneous change leads to directional selection on consumer phenology. This is because the consumer reaction norm has historically evolved to be flatter than the resource reaction norm, owing to time lags and imperfect cue reliability. Climate change will therefore lead to increased selection on consumer phenology across a broad range of situations.

  14. Selective carboxyl methylation of structurally altered calmodulins in Xenopus oocytes

    Energy Technology Data Exchange (ETDEWEB)

    Desrosiers, R.R.; Romanik, E.A.; O' Connor, C.M. (Worcester Foundation for Experimental Biology, Shrewsbury, MA (USA))

    1990-12-05

    The eucaryotic protein carboxyl methyltransferase specifically modifies atypical D-aspartyl and L-isoaspartyl residues which are generated spontaneously as proteins age. The selectivity of the enzyme for altered proteins in intact cells was explored by co-injecting Xenopus laevis oocytes with S-adenosyl-L-(methyl-3H)methionine and structurally altered calmodulins generated during a 14-day preincubation in vitro. Control experiments indicated that the oocyte protein carboxyl methyltransferase was not saturated with endogenous substrates, since protein carboxyl methylation rates could be stimulated up to 8-fold by increasing concentrations of injected calmodulin. The oocyte protein carboxyl methyltransferase showed strong selectivities for bovine brain and bacterially synthesized calmodulins which had been preincubated in the presence of 1 mM EDTA relative to calmodulins which had been preincubated with 1 mM CaCl2. Radioactive methyl groups were incorporated into base-stable linkages with recombinant calmodulin as well as into carboxyl methyl esters following its microinjection into oocytes. This base-stable radioactivity most likely represents the trimethylation of lysine 115, a highly conserved post-translational modification which is present in bovine and Xenopus but not in bacterially synthesized calmodulin. Endogenous oocyte calmodulin incorporates radioactivity into both carboxyl methyl esters and into base-stable linkages following microinjection of oocytes with S-adenosyl-(methyl-3H)methionine alone. The rate of oocyte calmodulin carboxyl methylation in injected oocytes is calculated to be similar to that of lysine 115 trimethylation, suggesting that the rate of calmodulin carboxyl methylation is similar to that of calmodulin synthesis. At steady state, oocyte calmodulin contains approximately 0.0002 esters/mol of protein, which turn over rapidly.

  15. Metabolic alterations in genetically selected Drosophila strains with different longevities.

    Science.gov (United States)

    Buck, S A; Arking, R

    2001-10-01

    Sometime ago we obtained biomarker data suggesting that the earliest determining event in the expression of the extended longevity phenotype in our selected strains of Drosophila took place early in adult life at about 5-7 days of age. In a later series of experiments we documented that our La and Lb long lived strains underwent a specific up-regulation of the antioxidant defense system (ADS) genes and enzymes. This led to a reduction in oxidative damage and an extended longevity. In the current work, we assayed the activity of 17 metabolically important enzymes in 5-7 day old flies of 13 strains variously selected for different longevities. We conclude that the two sets of replicated long-lived strains have an altered metabolic pattern (relative to normal-lived animals) which is consistent with an increased flux through the pentose shunt and an enhanced NADP+ reducing system to support the increased activity of the ADS enzymes. This result can be interpreted as a shift of energy expenditure from reproduction to somatic maintenance. We conclude that theories based on differential energy allocations appear to empirically explain, at least in part, the mechanisms underlying the transformation of a normal longevity phenotype to an extended longevity phenotype.

  16. The Development of Conductive Nanoporous Chitosan Polymer Membrane for Selective Transport of Charged Molecules

    Directory of Open Access Journals (Sweden)

    Pei-Ru Chen

    2013-01-01

    Full Text Available We present the development of conductive nanoporous CNT/chitosan membrane for charge-selective transport of charged molecules, carboxylfluorescein (CF, substance P, and tumor necrosis factor-alpha (TNF-α. The membrane was made porous and conductive via gelatin nanoparticle leaching technique and addition of carbon nanotubes, respectively. These nanoporous membranes discriminate the diffusion of positive-charged molecules while inhibiting the passage of negative-charged molecules as positive potential was applied. The permeation selectivity of these membranes is reversed by converting the polarity of applied potential into negative. Based on this principle, charged molecules (carboxylfluorescein, substance P, and TNF-α are successfully filtered through these membranes. This system shows 30 times more selective for CF than substance P as positive potential was applied, while 2.5 times more selective for substance P than CF as negative potential was applied.

  17. State selective capture by highly charged Xe ions

    NARCIS (Netherlands)

    Hasan, V. G.; Knoop, S.; Morgenstern, R.; Hoekstra, R.; McCullough, RW; Currell, FJ; Greenwood, J; Gribakin, G; Scott, MP

    2007-01-01

    Single-electron capture in collisions of highly charged ions Xe18+ and Xe24+ with Na atoms is investigated by measuring the momenta of the Na recoil ions. The Q-value spectrum in Xe18+ + Na collisions shows capture into lower n states compared with Classical over-barrier model (CBM) calculations.

  18. Selective charging of tRNA isoacceptors induced by amino-acid starvation

    Science.gov (United States)

    Dittmar, Kimberly A; Sørensen, Michael A; Elf, Johan; Ehrenberg, Måns; Pan, Tao

    2005-01-01

    Aminoacylated (charged) transfer RNA isoacceptors read different messenger RNA codons for the same amino acid. The concentration of an isoacceptor and its charged fraction are principal determinants of the translation rate of its codons. A recent theoretical model predicts that amino-acid starvation results in ‘selective charging' where the charging levels of some tRNA isoacceptors will be low and those of others will remain high. Here, we developed a microarray for the analysis of charged fractions of tRNAs and measured charging for all Escherichia coli tRNAs before and during leucine, threonine or arginine starvation. Before starvation, most tRNAs were fully charged. During starvation, the isoacceptors in the leucine, threonine or arginine families showed selective charging when cells were starved for their cognate amino acid, directly confirming the theoretical prediction. Codons read by isoacceptors that retain high charging can be used for efficient translation of genes that are essential during amino-acid starvation. Selective charging can explain anomalous patterns of codon usage in the genes for different families of proteins. PMID:15678157

  19. Charge-transfer-directed radical substitution enables para-selective C-H functionalization

    Science.gov (United States)

    Boursalian, Gregory B.; Ham, Won Seok; Mazzotti, Anthony R.; Ritter, Tobias

    2016-08-01

    Efficient C-H functionalization requires selectivity for specific C-H bonds. Progress has been made for directed aromatic substitution reactions to achieve ortho and meta selectivity, but a general strategy for para-selective C-H functionalization has remained elusive. Herein we introduce a previously unappreciated concept that enables nearly complete para selectivity. We propose that radicals with high electron affinity elicit arene-to-radical charge transfer in the transition state of radical addition, which is the factor primarily responsible for high positional selectivity. We demonstrate with a simple theoretical tool that the selectivity is predictable and show the utility of the concept through a direct synthesis of aryl piperazines. Our results contradict the notion, widely held by organic chemists, that radical aromatic substitution reactions are inherently unselective. The concept of radical substitution directed by charge transfer could serve as the basis for the development of new, highly selective C-H functionalization reactions.

  20. Selective Acylation Enhances Membrane Charge Sensitivity of the Antimicrobial Peptide Mastoparan-X

    DEFF Research Database (Denmark)

    Etzerodt, Thomas Povl; Henriksen, Jonas Rosager; Rasmussen, Palle

    2011-01-01

    change in the membrane partitioning properties of MPX and it was found that the shorter acylation with PA gave improved affinity and selectivity toward negatively charged membranes, whereas OA decreased the selectivity. Based on these findings, we hypothesize that minor differences in the embedding...

  1. Continuum-state selectivity in hydrogen in Stark fields by charge-shape tuning

    Energy Technology Data Exchange (ETDEWEB)

    Ying, Y.; Nayfeh, M.H.

    1987-02-15

    We present numerical calculations of the photoionization of atomic hydrogen in the presence of a strong dc electric field, using three-photon excitation with two-photon resonance with intermediate Stark states. The systematics of the dependence of the cross section on the intermediate Stark states is calculated for the n = 2 to n = 9 manifolds. Our results indicate that one can use ''charge-shape tuning'' to selectively excite and enhance Stark-induced giant dipoles near E = 0 in hydrogen without the excitation of the overlapping continuum. Frequency selectivity can be used to excite from 1s (spherical charge) an intermediate whose charge is focused along the field followed by another excitation to the giant dipoles. Charge tunability can be achieved by controlling the degree of focusing by choice of the field and intermediates.

  2. Scalable Graphene-Based Membranes for Ionic Sieving with Ultrahigh Charge Selectivity.

    Science.gov (United States)

    Hong, Seunghyun; Constans, Charlotte; Surmani Martins, Marcos Vinicius; Seow, Yong Chin; Guevara Carrió, Juan Alfredo; Garaj, Slaven

    2017-02-08

    Nanostructured graphene-oxide (GO) laminate membranes, exhibiting ultrahigh water flux, are excellent candidates for next generation nanofiltration and desalination membranes, provided the ionic rejection could be further increased without compromising the water flux. Using microscopic drift-diffusion experiments, we demonstrated the ultrahigh charge selectivity for GO membranes, with more than order of magnitude difference in the permeabilities of cationic and anionic species of equivalent hydration radii. Measuring diffusion of a wide range of ions of different size and charge, we were able to clearly disentangle different physical mechanisms contributing to the ionic sieving in GO membranes: electrostatic repulsion between ions and charged chemical groups; and the compression of the ionic hydration shell within the membrane's nanochannels, following the activated behavior. The charge-selectivity allows us to rationally design membranes with increased ionic rejection and opens up the field of ion exchange and electrodialysis to the GO membranes.

  3. Tuning transport selectivity of ionic species by phosphoric acid gradient in positively charged nanochannel membranes.

    Science.gov (United States)

    Yang, Meng; Yang, Xiaohai; Wang, Kemin; Wang, Qing; Fan, Xin; Liu, Wei; Liu, Xizhen; Liu, Jianbo; Huang, Jin

    2015-02-03

    The transport of ionic species through a nanochannel plays important roles in fundamental research and practical applications of the nanofluidic device. Here, we demonstrated that ionic transport selectivity of a positively charged nanochannel membrane can be tuned under a phosphoric acid gradient. When phosphoric acid solution and analyte solution were connected by the positively charged nanochannel membrane, the faster-moving analyte through the positively charged nanochannel membrane was the positively charged dye (methylviologen, MV(2+)) instead of the negatively charged dye (1,5-naphthalene disulfonate, NDS(2-)). In other words, a reversed ion selectivity of the nanochannel membranes can be found. It can be explained as a result of the combination of diffusion, induced electroosmosis, and induced electrophoresis. In addition, the influencing factors of transport selectivity, including concentration of phosphoric acid, penetration time, and volume of feed solution, were also investigated. The results showed that the transport selectivity can further be tuned by adjusting these factors. As a method of tuning ionic transport selectivity by establishing phosphoric acid gradient, it will be conducive to improving the separation of ionic species.

  4. Effect of Selected Organic Acids on Cadmium Sorption by Variable-and Permanent-Charge Soils

    Institute of Scientific and Technical Information of China (English)

    HU Hong-Qing; LIU Hua-Liang; HE Ji-Zheng; HUANG Qiao-Yun

    2007-01-01

    Batch equilibrium experiments were conducted to investigate cadmium (Cd) sorption by two permanent-charge soils, a yellow-cinnamon soil and a yellow-brown soil, and two variable-charge soils, a red soil and a latosol, with addition of selected organic acids (acetate, tartrate, and citrate). Results showed that with an increase in acetate concentrations from 0 to 3.0 mmol L-1, Cd sorption percentage by the yellow-cinnamon soil, the yellow-brown soil, and the latosol decreased. The sorption percentage of Cd by the yellow-cinnamon soil and generally the yellow-brown soil (permanent-charge soils)decreased with an increase in tartrate concentration, but increased at low tartrate concentrations for the red soil and the latosol. Curves of percentage of Cd sorption for citrate were similar to those for tartrate. For the variable-charge soils with tartrate and citrate, there were obvious peaks in Cd sorption percentage. These peaks, where organic acids had maximum influence, changed with soil type, and were at a higher organic acid concentration for the variable-charge soils than for the permanent charge soils. Addition of cadmium after tartrate adsorption resulted in higher sorption increase for the variable-charge soils than permanent-charge soils. When tartrate and Cd solution were added together, sorption of Cd decreased with tartrate concentration for the yellow-brown soil, but increased at low tartrate concentrations and then decreased with tartrate concentration for the red soil and the latosol.

  5. Memory generalization is selectively altered in the psychosis dimension.

    Science.gov (United States)

    Ivleva, Elena I; Shohamy, Daphna; Mihalakos, Perry; Morris, David W; Carmody, Thomas; Tamminga, Carol A

    2012-06-01

    Global deficits in declarative memory are commonly reported in individuals with schizophrenia and psychotic bipolar disorder, and in their biological relatives. However, it remains unclear whether there are specific components within the global declarative memory dysfunction that are unique to schizophrenia and bipolar disorder, or whether these impairments overlap the two psychoses. This study sought to characterize differential components of learning and memory in individuals within the psychosis dimension: probands with schizophrenia (SZP, n=33), probands with psychotic bipolar I disorder (BDP, n=20), and biological relatives of SZP (SZR, n=21), contrasted with healthy controls (HC, n=26). A computerized cognitive paradigm, the Acquired Equivalence test, with probes for associative learning, memory for learned associations, and memory generalization was administered, along with standardized neuropsychological measures of declarative memory. All study groups were able to learn and remember the associations, although SZP were slower than HC in the initial learning stages. Both SZP (significantly) and BDP (at a trend level) showed altered memory generalization compared to HC (SZP vs. HC, p=.038, d=.8; BDP vs. HC, p=.069, d=.95). SZR showed memory generalization intermediate between SZP and HC, although their performance did not differ significantly from either group. These findings indicate that probands with schizophrenia and bipolar psychoses have similar alteration in the ability to flexibly generalize learned knowledge when probed with novel stimuli, despite overall sufficient associative learning and memory for what they learned. These results suggest that the two disorders present a clinical continuum with overlapping hippocampus-mediated memory generalization dysfunction underlying the psychosis phenotype.

  6. Ion selection of charge-modified large nanopores in a graphene sheet

    Science.gov (United States)

    Zhao, Shijun; Xue, Jianming; Kang, Wei

    2013-09-01

    Water desalination becomes an increasingly important approach for clean water supply to meet the rapidly growing demand of population boost, industrialization, and urbanization. The main challenge in current desalination technologies lies in the reduction of energy consumption and economic costs. Here, we propose to use charged nanopores drilled in a graphene sheet as ion exchange membranes to promote the efficiency and capacity of desalination systems. Using molecular dynamics simulations, we investigate the selective ion transport behavior of electric-field-driven KCl electrolyte solution through charge modified graphene nanopores. Our results reveal that the presence of negative charges at the edge of graphene nanopore can remarkably impede the passage of Cl- while enhance the transport of K+, which is an indication of ion selectivity for electrolytes. We further demonstrate that this selectivity is dependent on the pore size and total charge number assigned at the nanopore edge. By adjusting the nanopore diameter and electric charge on the graphene nanopore, a nearly complete rejection of Cl- can be realized. The electrical resistance of nanoporous graphene, which is a key parameter to evaluate the performance of ion exchange membranes, is found two orders of magnitude lower than commercially used membranes. Our results thus suggest that graphene nanopores are promising candidates to be used in electrodialysis technology for water desalinations with a high permselectivity.

  7. Site-selective nanoscale-polymerization of pyrrole on gold nanoparticles via plasmon induced charge separation.

    Science.gov (United States)

    Takahashi, Y; Furukawa, Y; Ishida, T; Yamada, S

    2016-04-28

    We proposed a nanoscale oxidative polymerization method which enables site-selective deposition on the surface of gold nanoparticles (AuNPs) combined with TiO2 by using plasmon induced charge separation (PICS) under visible-to-near infrared (IR) light irradiation. The method also revealed that the anodic site of PICS was located at the surface of AuNPs.

  8. A metal ion charged mixed matrix membrane for selective adsorption of hemoglobin

    NARCIS (Netherlands)

    Tetala, K.K.R.; Skrzypek, K.; Levisson, M.; Stamatialis, D.F.

    2013-01-01

    In this work, we developed a mixed matrix membrane by incorporating 20–40 µm size iminodiacetic acid modified immobeads within porous Ethylene vinyl alcohol (EVAL) polymer matrix. The MMM were charged with copper ions for selective adsorption of bovine hemoglobin in presence of bovine serum albumin.

  9. Reversal of charge selectivity in transmembrane protein pores by using noncovalent molecular adapters

    Science.gov (United States)

    Gu, Li-Qun; Dalla Serra, Mauro; Vincent, J. Bryan; Vigh, Gyula; Cheley, Stephen; Braha, Orit; Bayley, Hagan

    2000-01-01

    In this study, the charge selectivity of staphylococcal α-hemolysin (αHL), a bacterial pore-forming toxin, is manipulated by using cyclodextrins as noncovalent molecular adapters. Anion-selective versions of αHL, including the wild-type pore and various mutants, become more anion selective when β-cyclodextrin (βCD) is lodged within the channel lumen. By contrast, the negatively charged adapter, hepta-6-sulfato-β-cyclodextrin (s7βCD), produces cation selectivity. The cyclodextrin adapters have similar effects when placed in cation-selective mutant αHL pores. Most probably, hydrated Cl− ions partition into the central cavity of βCD more readily than K+ ions, whereas s7βCD introduces a charged ring near the midpoint of the channel lumen and confers cation selectivity through electrostatic interactions. The molecular adapters generate permeability ratios (PK+/PCl−) over a 200-fold range and should be useful in the de novo design of membrane channels both for basic studies of ion permeation and for applications in biotechnology. PMID:10760267

  10. 选择性罪名研究%Studies on Selective Charges

    Institute of Scientific and Technical Information of China (English)

    李凤梅

    2015-01-01

    Selective Charges is the highly generalization of counts with several selective elements ,and also the Judicial inter-pretation choice of Supreme People’s Court and The Supreme People’s Procurator ate,for the purpose of meeting the demand of legislation and making the system of charges regular.The same of Affiliated articles,independence of sub-constitution,same quality of the selective elements and the logical relation of Paralleling,containing or absorbing among selective elements are the basis of the charges.The principle of Taking as One Crime of selective charges will lead to the imbalance between crime and punishment,so the punish rules should be determined according to the facts;in the conditions of different discontinuing form, logical relations should be distinguished and the punish rules on Inchoate crime stipulated in General Parts should be taken;in the condition of concurrence between sub-charges and other charges,punishing rules of articles concurrence should be consid-ered firstly,and combined punishment should be taken if the sub-charges and other charges concurred.%选择性罪名是“两高”对存在多个同类构成要素、或者分别表现为多种形态的数个不同类构成要素的罪状的高度概括,是司法解释的一种选择。附属法条的同一性、纯正亚犯罪构成的独立性、选择性要素的同质性、以及各选择性要素间的逻辑勾连,是选择性罪名确定的主要依据。对选择性罪名“以一罪认定”可能导致罪刑失衡,应根据具体情况,决定是否适用数罪并罚。

  11. Altering intra- to inter-molecular hydrogen bonding by dimethylsulfoxide: A TDDFT study of charge transfer for coumarin 343

    Science.gov (United States)

    Liu, Xiaochun; Yin, Hang; Li, Hui; Shi, Ying

    2017-04-01

    DFT and TDDFT methods were carried out to investigate the influences of intramolecular and intermolecular hydrogen bonding on excited state charge transfer for coumarin 343 (C343). Intramolecular hydrogen bonding is formed between carboxylic acid group and carbonyl group in C343 monomer. However, in dimethylsulfoxide (DMSO) solution, DMSO 'opens up' the intramolecular hydrogen bonding and forms solute-solvent intermolecular hydrogen bonded C343-DMSO complex. Analysis of frontier molecular orbitals reveals that intramolecular charge transfer (ICT) occurs in the first excited state both for C343 monomer and complex. The results of optimized geometric structures indicate that the intramolecular hydrogen bonding interaction is strengthened while the intermolecular hydrogen bonding is weakened in excited state, which is confirmed again by monitoring the shifts of characteristic peaks of infrared spectra. We demonstrated that DMSO solvent can not only break the intramolecular hydrogen bonding to form intermolecular hydrogen bonding with C343 but also alter the mechanism of excited state hydrogen bonding strengthening.

  12. Measurements of Ion Selective Containment on the RF Charge Breeder Device BRIC

    CERN Document Server

    Variale, Vincenzo; Batazova, Marina; Boggia, Antonio; Clauser, Tarcisio; Kuznetsov, Gennady I; Rainò, Antonio; Shiyankov, Sergey; Skarbo, Boris A; Valentino, Vincenzo; Verrone, Grazia

    2005-01-01

    The "charge state breeder" BRIC (BReeding Ion Charge) is based on an EBIS source and it is designed to accept Radioactive Ion Beam (RIB) with charge +1, in a slow injection mode, to increase their charge state up to +n. BRIC has been developed at the INFN section of Bari (Italy) during these last 3 years with very limited funds. Now, it has been assembled at the LNL (Italy) where are in progress the first tests as stand alone source. The new feature of BRIC, with respect to the classical EBIS, is given by the insertion, in the ion drift chamber, of a Radio Frequency (RF) Quadrupole aiming to filtering the unwanted elements and then making a more efficient containment of the wanted ions. In this contribution, the measurements of the selective effect on the ion charge state containement of the RF quadrupole field, applied on the ion chamber, will be reported and discussed. The ion charge state analisys of the ions trapped in BRIC seem confirm, as foreseen by simulation results carried out previously, that the s...

  13. Selective pressure to increase charge in immunodominant epitopes of the H3 hemagglutinin influenza protein.

    Science.gov (United States)

    Pan, Keyao; Long, Jinxue; Sun, Haoxin; Tobin, Gregory J; Nara, Peter L; Deem, Michael W

    2011-01-01

    The evolutionary speed and the consequent immune escape of H3N2 influenza A virus make it an interesting evolutionary system. Charged amino acid residues are often significant contributors to the free energy of binding for protein-protein interactions, including antibody-antigen binding and ligand-receptor binding. We used Markov chain theory and maximum likelihood estimation to model the evolution of the number of charged amino acids on the dominant epitope in the hemagglutinin protein of circulating H3N2 virus strains. The number of charged amino acids increased in the dominant epitope B of the H3N2 virus since introduction in humans in 1968. When epitope A became dominant in 1989, the number of charged amino acids increased in epitope A and decreased in epitope B. Interestingly, the number of charged residues in the dominant epitope of the dominant circulating strain is never fewer than that in the vaccine strain. We propose these results indicate selective pressure for charged amino acids that increase the affinity of the virus epitope for water and decrease the affinity for host antibodies. The standard PAM model of generic protein evolution is unable to capture these trends. The reduced alphabet Markov model (RAMM) model we introduce captures the increased selective pressure for charged amino acids in the dominant epitope of hemagglutinin of H3N2 influenza (R (2) > 0.98 between 1968 and 1988). The RAMM model calibrated to historical H3N2 influenza virus evolution in humans fit well to the H3N2/Wyoming virus evolution data from Guinea pig animal model studies.

  14. Charge-selective fractions of naturally occurring nanoparticles as bioactive nanocarriers for cancer therapy.

    Science.gov (United States)

    Wang, Yongzhong; Yi, Sijia; Sun, Leming; Huang, Yujian; Zhang, Mingjun

    2014-10-01

    A carnivorous fungus, Arthrobotrys oligospora, has been shown to secrete nanoparticles. In the present work, the potential of two charge-selective fractions of fungal nanoparticles (FNPs) as bioactive nanocarriers in cancer therapy is explored by investigating their immunostimulatory activities, cytotoxic mechanisms and in vitro immunochemotherapeutic effects. A surface charge-selective fractionation procedure to purify crude FNPs has been established, and two FNP fractions (i.e. FNP1 and FNP2), with different surface charges and similarly reduced diameters of 100-200nm, are obtained. Both FNP fractions enhance the secretion of multiple proinflammatory cytokines and chemokines from macrophages and splenocytes. However, FNP2 has stronger cytotoxicity than FNP1. It is FNP2 not FNP1 that could clearly inhibit cell proliferation by inducing apoptosis and arresting cells at the sub G0/G1 phase. Both the FNP fractions can form pH-responsive nanocomplexes with doxorubicin (DOX) via electrostatic interactions. For direct cytotoxicity, DOX-FNP2 complexes demonstrate higher activity than DOX against multiple tumor cells, while DOX-FNP1 complexes show weaker activity than DOX. Interestingly, in a co-culture experiment where splenocytes are co-cultured with tumor cells, both DOX-FNP complexes demonstrate higher cytotoxicity than DOX. In conclusion, this work proposes a combined therapeutics for cancer treatment using charge-selective fractions of FNPs as bioactive nanocarriers.

  15. Glomerular size and charge selectivity in insulin-dependent diabetes mellitus

    DEFF Research Database (Denmark)

    Deckert, T; Feldt-Rasmussen, B; Djurup, R

    1988-01-01

    studied. In diabetic patients with normal urinary albumin excretion (less than 30 mg/24 hr), fractional IgG clearance was two to three times higher than in control subjects, whereas fractional clearance of the anionic plasma proteins IgG4 and albumin was similar to that of control subjects......G compared to patients with normal albumin excretion, while fractional IgG4 and albumin clearances were increased three- to fourfold; indicating unchanged glomerular pore size, but a decrease in anionic pore charge. In patients demonstrating urinary albumin excretion of greater than 100 mg/24 hr fractional....... These alterations indicate an increase in anionic pore charge within the glomerular basement membrane concomitant with an increase in either pore size or impairment of tubular reabsorption. Diabetic patients, whose urinary albumin excretion has started to rise (30 to 100 mg/24 hr), had unchanged fractional Ig...

  16. Selective targeting of cellular nucleus using positively-charged quantum dots.

    Science.gov (United States)

    Lee, Junghan; Choi, Youngseon; Cho, Yoojin; Song, Rita

    2013-01-01

    Developing highly selective probes for subcellular regions such as nucleus and cytoplamic organelles is of great interest for cellular imaging and high content screening analysis for biology and medicine. Cytoplasmic delivery of QDs has been well-understood, while nuclear delivery of QDs has been a challenge due to the unique structural characteristics of cell nucleus. In this study, we systematically investigated nucleus penetrating properties of small-sized ligand-exchanged QDs with either positive or negative surface charges in the similar size range of hydrodynamic diameter (7-10 nm). We found that the positively-charged QDs efficiently stain the nucleus in fixed HeLa cells as well as label nucleolar compartments in live HeLa cells. In contrast, the negatively charged QDs with the similar size range stain only the cytoplam in either fixed or live cells. The charge-dependent labeling pattern allowed us to simultaneously perform multiplex imaging of nuclues and cytoplasm. This study offers an insight into efficient nuclear delivery of nanoparticles such as QDs of which surface charge and size are critical for intracelllar localization and delivery.

  17. An invasive plant alters pollinator-mediated phenotypic selection on a native congener.

    Science.gov (United States)

    Beans, Carolyn M; Roach, Deborah A

    2015-01-01

    • Recent studies suggest that invasive plants compete reproductively with native plants by reducing the quantity or quality of pollinator visits. Although these studies have revealed ecological consequences of pollinator-mediated competition between invasive and native plants, the evolutionary outcomes of these interactions remain largely unexplored.• We studied the ecological and evolutionary impact of pollinator-mediated competition with an invasive jewelweed, Impatiens glandulifera, on a co-occurring native congener, I. capensis. Using a pollinator choice experiment, a hand pollination experiment, and a selection analysis, we addressed the following questions: (1) Do native pollinators show preference for the invasive or native jewelweed, and do they move between the two species? (2) Does invasive jewelweed pollen inhibit seed production in the native plant? (3) Does the invasive jewelweed alter phenotypic selection on the native plant's floral traits?• The pollinator choice experiment showed that pollinators strongly preferred the invasive jewelweed. The hand pollination experiment demonstrated that invasive pollen inhibited seed production in the native plant. The selection analysis showed that the presence of the invasive jewelweed altered phenotypic selection on corolla height in the native plant.• Invasive plants have the potential to alter phenotypic selection on floral traits in native plant populations. If native plants can evolve in response to this altered selection pressure, the evolution of floral traits may play an important role in permitting long-term coexistence of native and invasive plants. © 2015 Botanical Society of America, Inc.

  18. Highly selective uptake and release of charged molecules by pH-responsive polydopamine microcapsules.

    Science.gov (United States)

    Liu, Qinze; Yu, Bo; Ye, Weichun; Zhou, Feng

    2011-09-09

    A systematic study of the permeation of small molecules through Pdop microcapsules is reported. The zwitterionic Pdop microcapsules are prepared by oxidative polymerization of dopamine on polystyrene microspheres followed by core removal with THF. Rhodamine 6G, methyl orange and alizarin red are chosen as differently charged probing dyes. The loading amount is affected by pH and dye concentration. Highly selective and unidirectional uptake and release of charged molecules through Pdop microcapsules can be achieved by controlling pH value: at low pH, the Pdop particles incorporate cationic dye (rhodamine 6G); at high pH, they incorporate anionic dyes (methyl orange and alizarin red). In each case, the uptake is highly selective. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. An invasive plant alters phenotypic selection on the vegetative growth of a native congener.

    Science.gov (United States)

    Beans, Carolyn M; Roach, Deborah A

    2015-02-01

    The ecological consequences of plant competition have frequently been tested, but the evolutionary outcomes of these interactions have gone largely unexplored. The study of species invasions can make an important contribution to this field of research by allowing us to watch ecological and evolutionary processes unfold as a novel species is integrated into a plant community. We explored the ecological and evolutionary impact of an invasive jewelweed, Impatiens glandulifera, on a closely related native congener, I. capensis and asked: (1) Does the presence of the invasive jewelweed alter the fitness of native jewelweed populations? (2) Does the invasive jewelweed affect the vegetative growth of the native congener? and (3) Does the invasive jewelweed alter phenotypic selection on the vegetative traits of the native congener? We used a greenhouse competition experiment, an invasive species removal field experiment, and a survey of natural populations. We show that when the invasive jewelweed is present, phenotypic selection favors native jewelweed individuals investing less in rapid upward growth and more in branching and fruiting potential through the production of nodes. This research demonstrates that invasive plants have the potential to greatly alter natural selection on native competitors. Studies investigating altered selection in invaded communities can reveal the potential evolutionary impact of invasive competitors, while deepening our understanding of the more general role of competition in driving plant evolution and permitting species coexistence. © 2015 Botanical Society of America, Inc.

  20. High yield sample preconcentration using a highly ion-conductive charge-selective polymer.

    Science.gov (United States)

    Chun, Honggu; Chung, Taek Dong; Ramsey, J Michael

    2010-07-15

    The development and analysis of a microfluidic sample preconcentration system using a highly ion-conductive charge-selective polymer [poly-AMPS (2-acrylamido-2-methyl-1-propanesulfonic acid)] is reported. The preconcentration is based on the phenomenon of concentration polarization which develops at the boundaries of the poly-AMPS with buffer solutions. A negatively charged polymer, poly-AMPS, positioned between two microchannels efficiently extracts cations through its large cross section, resulting in efficient anion sample preconcentration. The present work includes the development of a robust polymer that is stable over a wide range of buffers with varying chemical compositions. The sample preconcentration effect remains linear to over 3 mM (0.15 pmol) and 500 microM (15 fmol) for fluorescein and TRITC-tagged albumin solutions, respectively. The system can potentially be used for concentrating proteins on microfluidic devices with subsequent analysis for proteomic applications.

  1. Implications of lipid monolayer charge characteristics on their selective interactions with a short antimicrobial peptide.

    Science.gov (United States)

    Ciumac, Daniela; Campbell, Richard A; Xu, Hai; Clifton, Luke A; Hughes, Arwel V; Webster, John R P; Lu, Jian R

    2017-02-01

    Many antimicrobial peptides (AMPs) target bacterial membranes and they kill bacteria by causing structural disruptions. One of the fundamental issues however lies in the selective responses of AMPs to different cell membranes as a lack of selectivity can elicit toxic side effects to mammalian host cells. A key difference between the outer surfaces of bacterial and mammalian cells is the charge characteristics. We report a careful study of the binding of one of the representative AMPs, with the general sequence G(IIKK)4I-NH2 (G4), to the spread lipid monolayers of DPPC (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) and DPPG (1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt)) mimicking the charge difference between them, using the combined measurements from Langmuir trough, Brewster angle microscopy (BAM) and neutron reflection (NR). The difference in pressure rise upon peptide addition into the subphase clearly demonstrated the different interactions arising from different lipid charge features. Morphological changes from the BAM imaging confirmed the association of the peptide into the lipid monolayers, but there was little difference between them. However, NR studies revealed that the peptide bound 4 times more onto the DPPG monolayer than onto the DPPC monolayer. Importantly, whilst the peptide could only be associated with the head groups of DPPC it was well penetrated into the entire DPPG monolayer, showing that the electrostatic interaction strengthened the hydrophobic interaction and that the combined molecular interactive processes increased the power of G4 in disrupting the charged membranes. The results are discussed in the context of general antibacterial actions as observed from other AMPs and membrane lytic actions.

  2. Progressive alterations of central nervous system structure and function are caused by charged particle radiation

    Science.gov (United States)

    Nelson, G. A.; Cns Nscor Team

    A new NASA-sponsored program project (NSCOR) has been organized to conduct the first comprehensive investigation of the response of a mammalian brain structure (mouse hippocampus) to charged-particle radiation. The NSCOR collaboration has three main goals. The first goal is to quantify the time- and dose-dependent changes in cellular composition and architecture. By using stereology on preserved brains, subsets of cells (neurons, glia, endothelia and stem cells) will be quantified out to 2 years after irradiation with accelerated protons and iron ions. To further characterize changes in vasculature architecture a polymer infusion technique will be used to produce a three-dimensional vasculature cast that then will be mapped by x-ray tomography to determine topological changes, and microscopic infarcts associated with amyloid protein deposits. The 2nd goal is to quantify hippocampal function(s). The primary measurement of function will be extracellular electrical recordings from hippocampal ``brain slices'' that reflect underlying functions such as connectivity, action potential generation & conduction, and neurotransmitter formation, secretion, and uptake. Individual nerve membrane properties will be assessed by ``patch clamp'' recordings. Two non-invasive methods will evaluate brain function and the evolution of changes with time. Electroencephalograms will map macroscopic spontaneous electrical activity while two state-of-the-art MRI magnetization sequences will visualize and quantify local oxygen utilization and white matter fiber tracts structural integrity. To quantify the brains' overall performance under stress, animals will receive a systemic shock mediated by the immune system in the form of a reaction to lipopolysaccharide. A second strategy will employ the APP23 transgenic mouse that develops the pathological changes associated with Alzheimer's disease. Measurements of irradiated mice will determine whether radiation exposure affects the latency and

  3. The selectivity of charged phenyl radicals in hydrogen atom abstraction reactions with isopropanol.

    Science.gov (United States)

    Jing, Linhong; Guler, Leonard P; Pates, George; Kenttämaa, Hilkka I

    2008-10-09

    The vertical electron affinity is demonstrated to be a key factor in controlling the selectivity of charged phenyl radicals in hydrogen atom abstraction from isopropanol in the gas phase. The measurement of the total reaction efficiencies (hydrogen and/or deuterium atom abstraction) for unlabeled and partially deuterium-labeled isopropanol, and the branching ratios of hydrogen and deuterium atom abstraction, by using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer, allowed the determination of the selectivity for each site in the unlabeled isopropanol. Examination of hydrogen atom abstraction from isopropanol by eight structurally different radicals revealed that the preferred site is the CH group. The selectivity of the charged phenyl radicals correlates with the radical's vertical electron affinity and the reaction efficiency. The smaller the vertical electron affinity of a radical, the lower its reactivity, and the greater the preference for the thermodynamically favored CH group over the CH3 group or the OH group. As the vertical electron affinity increases from 4.87 to 6.28 eV, the primary kinetic isotope effects decrease from 2.9 to 1.3 for the CD group, and the mixture of primary and alpha-secondary kinetic isotopes decreases from 6.0 to 2.4 for the CD3 group.

  4. Evidence of double layer/capacitive charging in carbon nanomaterial-based solid contact polymeric ion-selective electrodes.

    Science.gov (United States)

    Cuartero, Maria; Bishop, Josiah; Walker, Raymart; Acres, Robert G; Bakker, Eric; De Marco, Roland; Crespo, Gaston A

    2016-08-11

    This paper presents the first direct spectroscopic evidence for double layer or capacitive charging of carbon nanomaterial-based solid contacts in all-solid-state polymeric ion-selective electrodes (ISEs). Here, we used synchrotron radiation-X-ray photoelectron spectroscopy (SR-XPS) and SR valence band (VB) spectroscopy in the elucidation of the charging mechanism of the SCs.

  5. The selected response procedure: a variation on Appelbaum's altered atmosphere procedure for the Rorschach.

    Science.gov (United States)

    Jaffe, L

    1988-01-01

    This article introduces the Selected Response Procedure, which is a supplementary technique for expanding the scope of the Rorschach test. The procedure is conducted as follows: After the standard administration of the Rorschach test, patients are asked to look through all of the cards a second time and select one more response from any card of their choice. A rationale for this procedure is developed through a comparison to another supplementary Rorschach technique, the Altered Atmosphere Procedure. The importance of understanding the selected response within a theoretical framework, as well as the clinical context of each selected response, is highlighted by a clinical example using object relations theory. Finally, a number of didactic questions are offered as potential ways to query the possible meaning of selected responses.

  6. Beam angle selection incorporation of anatomical heterogeneities for pencil beam scanning charged-particle therapy

    Science.gov (United States)

    Toramatsu, Chie; Inaniwa, Taku

    2016-12-01

    In charged particle therapy with pencil beam scanning (PBS), localization of the dose in the Bragg peak makes dose distributions sensitive to lateral tissue heterogeneities. The sensitivity of a PBS plan to lateral tissue heterogeneities can be reduced by selecting appropriate beam angles. The purpose of this study is to develop a fast and accurate method of beam angle selection for PBS. The lateral tissue heterogeneity surrounding the path of the pencil beams at a given angle was quantified with the heterogeneity number representing the variation of the Bragg peak depth across the cross section of the beams using the stopping power ratio of body tissues with respect to water. To shorten the computation time, one-dimensional dose optimization was conducted along the central axis of the pencil beams as they were directed by the scanning magnets. The heterogeneity numbers were derived for all possible beam angles for treatment. The angles leading to the minimum mean heterogeneity number were selected as the optimal beam angle. Three clinical cases of head and neck cancer were used to evaluate the developed method. Dose distributions and their robustness to setup and range errors were evaluated for all tested angles, and their relation to the heterogeneity numbers was investigated. The mean heterogeneity number varied from 1.2 mm-10.6 mm in the evaluated cases. By selecting a field with a low mean heterogeneity number, target dose coverage and robustness against setup and range errors were improved. The developed method is simple, fast, accurate and applicable for beam angle selection in charged particle therapy with PBS.

  7. Understory avifauna exhibits altered mobbing behavior in tropical forest degraded by selective logging.

    Science.gov (United States)

    Hua, Fangyuan; Sieving, Kathryn E

    2016-11-01

    In understanding the impacts of selective logging on biodiversity, relatively little is known about the critical behavioral link between altered forest conditions and population persistence. Predator-mobbing is a widespread anti-predator behavior in birds that expresses a well-known trade-off influencing prey survival under predation risk. Here, we ask whether the predator-mobbing behavior of understory forest birds is altered by selective logging and associated forest structural changes in the highly endangered lowland rainforest of Sumatra. At four study sites spanning a gradient of logging-induced forest degradation, we used standardized mobbing and owl call playbacks with predator model presentation to elicit the predator-mobbing behavior of understory prey birds, compared birds' mobbing intensity across sites, and related variation in this intensity to forest vegetation structure. We found that selective logging altered birds' predator-mobbing intensity (measured by behavioral conspicuousness and propensity to approach the predator) as well as forest structure, and that vegetative changes to canopy and understory were correlated with contrasting responses by the two major bird foraging guilds, gleaning versus flycatching birds. We additionally discuss the implications of our findings for further hypothesis testing pertaining to the impacts of selective logging on the ecological processes underlying prey mobbing behavior, particularly with regards to predator-prey interactions and prey accruement of energy reserves.

  8. Oxidized fatty acid analysis by charge-switch derivatization, selected reaction monitoring, and accurate mass quantitation.

    Science.gov (United States)

    Liu, Xinping; Moon, Sung Ho; Mancuso, David J; Jenkins, Christopher M; Guan, Shaoping; Sims, Harold F; Gross, Richard W

    2013-11-01

    A highly sensitive, specific, and robust method for the analysis of oxidized metabolites of linoleic acid (LA), arachidonic acid (AA), and docosahexaenoic acid (DHA) was developed using charge-switch derivatization, liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI MS/MS) with selected reaction monitoring (SRM) and quantitation by high mass accuracy analysis of product ions, thereby minimizing interferences from contaminating ions. Charge-switch derivatization of LA, AA, and DHA metabolites with N-(4-aminomethylphenyl)-pyridinium resulted in a 10- to 30-fold increase in ionization efficiency. Improved quantitation was accompanied by decreased false positive interferences through accurate mass measurements of diagnostic product ions during SRM transitions by ratiometric comparisons with stable isotope internal standards. The limits of quantitation were between 0.05 and 6.0pg, with a dynamic range of 3 to 4 orders of magnitude (correlation coefficient r(2)>0.99). This approach was used to quantitate the levels of representative fatty acid metabolites from wild-type (WT) and iPLA2γ(-/-) mouse liver identifying the role of iPLA2γ in hepatic lipid second messenger production. Collectively, these results demonstrate the utility of high mass accuracy product ion analysis in conjunction with charge-switch derivatization for the highly specific quantitation of diminutive amounts of LA, AA, and DHA metabolites in biologic systems. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Beyond the ecological: biological invasions alter natural selection on a native plant species.

    Science.gov (United States)

    Lau, Jennifer A

    2008-04-01

    Biological invasions can have strong ecological effects on native communities by altering ecosystem functions, species interactions, and community composition. Even though these ecological effects frequently impact the population dynamics and fitness of native species, the evolutionary consequences of biological invasions have received relatively little attention. Here, I show that invasions impose novel selective pressures on a native plant species. By experimentally manipulating community composition, I found that the exotic plant Medicago polymorpha and the exotic herbivore Hypera brunneipennis alter the strength and, in some instances, the direction of natural selection on the competitive ability and anti-herbivore defenses of the native plant Lotus wrangelianus. Furthermore, the community composition of exotics influenced which traits were favored. For example, high densities of the exotic herbivore Hypera selected for increased resistance to herbivores in the native Lotus; however, when Medicago also was present, selection on this defense was eliminated. In contrast, selection on tolerance, another plant defense trait, was highest when both Hypera and Medicago were present at high densities. Thus, multiple exotic species may interact to influence the evolutionary trajectories of native plant populations, and patterns of selection may change as additional exotic species invade the community.

  10. Charged residues distribution modulates selectivity of the open state of human isoforms of the voltage dependent anion-selective channel.

    Science.gov (United States)

    Amodeo, Giuseppe Federico; Scorciapino, Mariano Andrea; Messina, Angela; De Pinto, Vito; Ceccarelli, Matteo

    2014-01-01

    Voltage Dependent Anion-selective Channels (VDACs) are pore-forming proteins located in the outer mitochondrial membrane. They are responsible for the access of ions and energetic metabolites into the inner membrane transport systems. Three VDAC isoforms exist in mammalian, but their specific role is unknown. In this work we have performed extensive (overall ∼5 µs) Molecular Dynamics (MD) simulations of the human VDAC isoforms to detect structural and conformational variations among them, possibly related to specific functional roles of these proteins. Secondary structure analysis of the N-terminal domain shows a high similarity among the three human isoforms of VDAC but with a different plasticity. In particular, the N-terminal domain of the hVDAC1 is characterized by a higher plasticity, with a ∼20% occurrence for the 'unstructured' conformation throughout the folded segment, while hVDAC2, containing a peculiar extension of 11 amino acids at the N-terminal end, presents an additional 310-helical folded portion comprising residues 10' to 3, adhering to the barrel wall. The N-terminal sequences of hVDAC isoforms are predicted to have a low flexibility, with possible consequences in the dynamics of the human VDACs. Clear differences were found between hVDAC1 and hVDAC3 against hVDAC2: a significantly modified dynamics with possible important consequence on the voltage-gating mechanism. Charge distribution inside and at the mouth of the pore is responsible for a different preferential localization of ions with opposite charge and provide a valuable rationale for hVDAC1 and hVDAC3 having a Cl-/K+ selectivity ratio of 1.8, whereas hVDAC2 of 1.4. Our conclusion is that hVDAC isoforms, despite sharing a similar scaffold, have modified working features and a biological work is now requested to give evidence to the described dissimilarities.

  11. Superconducting curved transport solenoid with dipole coils for charge selection of the muon beam

    Energy Technology Data Exchange (ETDEWEB)

    Strasser, P., E-mail: patrick.strasser@kek.jp [Muon Science Laboratory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); J-PARC Center, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Ikedo, Y.; Miyake, Y.; Shimomura, K.; Kawamura, N.; Nishiyama, K.; Makimura, S.; Fujimori, H.; Koda, A.; Nakamura, J.; Nagatomo, T. [Muon Science Laboratory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); J-PARC Center, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Adachi, T. [Department of Physics, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Pant, A.D. [Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 4-3-11 Takeda, Kofu 400-8511 (Japan); Ogitsu, T. [Cryogenic Science Center, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); J-PARC Center, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Makida, Y.; Yoshida, M. [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); J-PARC Center, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Sasaki, K. [Cryogenic Science Center, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); J-PARC Center, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Okamura, T. [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); J-PARC Center, 2-4 Shirane Shirakata, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); and others

    2013-12-15

    Highlights: • Superconducting curved transport solenoid. • Muon charge selection by superimposed dipole field. • World strongest pulsed muon source. -- Abstract: At the J-PARC Muon Science Facility (MUSE) the Super-Omega muon beamline is now under construction in the experimental hall No. 2 of the Materials and Life Science Facility building. Muons up to 45 MeV/c will be extracted with a large acceptance solid angle to produce the world highest intensity pulsed muon beam. This beamline comprises three parts, a normal-conducting capture solenoid, a superconducting curved transport solenoid and an axial focusing solenoid. Since only solenoids are used, both surface μ{sup +} and cloud μ{sup −} are extracted simultaneously. To accommodate future experiments that would only require either μ{sup +} or μ{sup −} beam, two dipole coils located on the straight section of the curved solenoid provide the muon charge selection by directing one of the beam onto the solenoid inner-wall. The design parameters, the construction status and the initial beam commissioning are reported.

  12. Altered complementary feeding strategies of the consumers Hydrobia ulvae and Idotea emarginata via passive selectivity

    Science.gov (United States)

    Aberle, N.; Malzahn, A. M.; Grey, J.; Hillebrand, H.; Wiltshire, K. H.

    2009-09-01

    This study aimed to identify differences in selectivity, foraging behaviour and complementary feeding of two benthic consumers (the isopod Idotea emarginata and the snail Hydrobia ulvae) using traditional cell counting as an indicator for algal biomass reduction and stable isotope labelling to detect differences in assimilation and digestion. We hypothesized that even when active feeding preferences of food components are not apparent, passive selectivity via mechanisms such as food assimilation and digestion can be of relevance. Algal biomass was reduced to a similar degree by the grazers independently from grazer and prey combinations without any indication for an active choice of food components. However, the isotope labelling approach indicated that passive selectivity can alter complementary feeding strategies, as we detected shifts in feeding preferences in relation to food quantity and competition. Thus, stable isotope labelling of food components opens up new perspectives in community ecology, allowing assessment of such complex mechanisms as passive selectivity, complementary feeding and competition.

  13. Functional divergence of the NIP III subgroup proteins involved altered selective constraints and positive selection

    Directory of Open Access Journals (Sweden)

    Zhu Zhujun

    2010-11-01

    Full Text Available Abstract Background Nod26-like intrinsic proteins (NIPs that belong to the aquaporin superfamily are unique to plants. According to homology modeling and phylogenetic analysis, the NIP subfamily can be further divided into three subgroups with distinct biological functions (NIP I, NIP II, and NIP III. In some grasses, the NIP III subgroup proteins (NIP2s were demonstrated to be permeable to solutes with larger diameter, such as silicic acid and arsenous acids. However, to date there is no data-mining or direct experimental evidences for the permeability of such larger solutes for dicot NIP2s, although they exhibit similar three-dimensional structures as those in grasses. It is therefore intriguing to investigate the molecular mechanisms that drive the evolution of plant NIP2s. Results The NIP III subgroup is more ancient with a divergence time that predates the monocot-dicot split. The proliferation of NIP2 genes in modern grass species is primarily attributed to whole genome and segmental chromosomal duplication events. The structure of NIP2 genes is relatively conserved, possessing five exons and four introns. All NIP2s possess an ar/R filter consisting of G, S, G, and R, except for the cucumber CsNIP2;2, where a small G in the H2 is substituted with the bulkier C residue. Our maximum likelihood analysis revealed that NIP2s, especially the loop A (LA region, have undergone strong selective pressure for adaptive evolution. The analysis at the amino acid level provided strong statistical evidences for the functional divergence between monocot and dicot NIP III subgroup proteins. In addition, several SDPs (Specificity Determining Positions responsible for functional specificity were predicted. Conclusions The present study provides the first evidences of functional divergence between dicot and monocot NIP2s, and suggests that positive selection, as well as a radical shift of evolutionary rate at some critical amino acid sites is the primary

  14. RNS60, a charge-stabilized nanostructure saline alters Xenopus Laevis oocyte biophysical membrane properties by enhancing mitochondrial ATP production.

    Science.gov (United States)

    Choi, Soonwook; Yu, Eunah; Kim, Duk-Soo; Sugimori, Mutsuyuki; Llinás, Rodolfo R

    2015-03-01

    We have examined the effects of RNS60, a 0.9% saline containing charge-stabilized oxygen nanobubble-based structures. RNS60 is generated by subjecting normal saline to Taylor-Couette-Poiseuille (TCP) flow under elevated oxygen pressure. This study, implemented in Xenopus laevis oocytes, addresses both the electrophysiological membrane properties and parallel biological processes in the cytoplasm. Intracellular recordings from defolliculated X. laevis oocytes were implemented in: (1) air oxygenated standard Ringer's solution, (2) RNS60-based Ringer's solution, (3) RNS10.3 (TCP-modified saline without excess oxygen)-based Ringer's, and (4) ONS60 (saline containing high pressure oxygen without TCP modification)-based Ringer's. RNS60-based Ringer's solution induced membrane hyperpolarization from the resting membrane potential. This effect was prevented by: (1) ouabain (a blocker of the sodium/potassium ATPase), (2) rotenone (a mitochondrial electron transfer chain inhibitor preventing usable ATP synthesis), and (3) oligomycin A (an inhibitor of ATP synthase) indicating that RNS60 effects intracellular ATP levels. Increased intracellular ATP levels following RNS60 treatment were directly demonstrated using luciferin/luciferase photon emission. These results indicate that RNS60 alters intrinsic the electrophysiological properties of the X. laevis oocyte membrane by increasing mitochondrial-based ATP synthesis. Ultrastructural analysis of the oocyte cytoplasm demonstrated increased mitochondrial length in the presence of RNS60-based Ringer's solution. It is concluded that the biological properties of RNS60 relate to its ability to optimize ATP synthesis.

  15. Induced defences alter the strength and direction of natural selection on reproductive traits in common milkweed.

    Science.gov (United States)

    Thompson, K A; Cory, K A; Johnson, M T J

    2017-06-01

    Evolutionary biologists have long sought to understand the ecological processes that generate plant reproductive diversity. Recent evidence indicates that constitutive antiherbivore defences can alter natural selection on reproductive traits, but it is unclear whether induced defences will have the same effect and whether reduced foliar damage in defended plants is the cause of this pattern. In a factorial field experiment using common milkweed, Asclepias syriaca L., we induced plant defences using jasmonic acid (JA) and imposed foliar damage using scissors. We found that JA-induced plants experienced selection for more inflorescences that were smaller in size (fewer flowers), whereas control plants only experienced a trend towards selection for larger inflorescences (more flowers); all effects were independent of foliar damage. Our results demonstrate that induced defences can alter both the strength and direction of selection on reproductive traits, and suggest that antiherbivore defences may promote the evolution of plant reproductive diversity. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  16. Mode-selective vibrational modulation of charge transport in organic electronic devices

    KAUST Repository

    Bakulin, Artem A.

    2015-08-06

    The soft character of organic materials leads to strong coupling between molecular, nuclear and electronic dynamics. This coupling opens the way to influence charge transport in organic electronic devices by exciting molecular vibrational motions. However, despite encouraging theoretical predictions, experimental realization of such approach has remained elusive. Here we demonstrate experimentally that photoconductivity in a model organic optoelectronic device can be modulated by the selective excitation of molecular vibrations. Using an ultrafast infrared laser source to create a coherent superposition of vibrational motions in a pentacene/C60 photoresistor, we observe that excitation of certain modes in the 1,500–1,700 cm−1 region leads to photocurrent enhancement. Excited vibrations affect predominantly trapped carriers. The effect depends on the nature of the vibration and its mode-specific character can be well described by the vibrational modulation of intermolecular electronic couplings. This presents a new tool for studying electron–phonon coupling and charge dynamics in (bio)molecular materials.

  17. Selective contacts drive charge extraction in quantum dot solids via asymmetry in carrier transfer kinetics

    KAUST Repository

    Mora-Sero, Ivan

    2013-08-12

    Colloidal quantum dot solar cells achieve spectrally selective optical absorption in a thin layer of solution-processed, size-effect tuned, nanoparticles. The best devices built to date have relied heavily on drift-based transport due to the action of an electric field in a depletion region that extends throughout the thickness of the quantum dot layer. Here we study for the first time the behaviour of the best-performing class of colloidal quantum dot films in the absence of an electric field, by screening using an electrolyte. We find that the action of selective contacts on photovoltage sign and amplitude can be retained, implying that the contacts operate by kinetic preferences of charge transfer for either electrons or holes. We develop a theoretical model to explain these experimental findings. The work is the first to present a switch in the photovoltage in colloidal quantum dot solar cells by purposefully formed selective contacts, opening the way to new strategies in the engineering of colloidal quantum dot solar cells. © 2013 Macmillan Publishers Limited. All rights reserved.

  18. Selective contacts drive charge extraction in quantum dot solids via asymmetry in carrier transfer kinetics

    Science.gov (United States)

    Mora-Sero, Ivan; Bertoluzzi, Luca; Gonzalez-Pedro, Victoria; Gimenez, Sixto; Fabregat-Santiago, Francisco; Kemp, Kyle W.; Sargent, Edward H.; Bisquert, Juan

    2013-08-01

    Colloidal quantum dot solar cells achieve spectrally selective optical absorption in a thin layer of solution-processed, size-effect tuned, nanoparticles. The best devices built to date have relied heavily on drift-based transport due to the action of an electric field in a depletion region that extends throughout the thickness of the quantum dot layer. Here we study for the first time the behaviour of the best-performing class of colloidal quantum dot films in the absence of an electric field, by screening using an electrolyte. We find that the action of selective contacts on photovoltage sign and amplitude can be retained, implying that the contacts operate by kinetic preferences of charge transfer for either electrons or holes. We develop a theoretical model to explain these experimental findings. The work is the first to present a switch in the photovoltage in colloidal quantum dot solar cells by purposefully formed selective contacts, opening the way to new strategies in the engineering of colloidal quantum dot solar cells.

  19. Spin Selective Charge Transport through Cysteine Capped CdSe Quantum Dots.

    Science.gov (United States)

    Bloom, Brian P; Kiran, Vankayala; Varade, Vaibhav; Naaman, Ron; Waldeck, David H

    2016-07-13

    This work demonstrates that chiral imprinted CdSe quantum dots (QDs) can act as spin selective filters for charge transport. The spin filtering properties of chiral nanoparticles were investigated by magnetic conductive-probe atomic force microscopy (mCP-AFM) measurements and magnetoresistance measurements. The mCP-AFM measurements show that the chirality of the quantum dots and the magnetic orientation of the tip affect the current-voltage curves. Similarly, magnetoresistance measurements demonstrate that the electrical transport through films of chiral quantum dots correlates with the chiroptical properties of the QD. The spin filtering properties of chiral quantum dots may prove useful in future applications, for example, photovoltaics, spintronics, and other spin-driven devices.

  20. Optofluidic in situ maskless lithography of charge selective nanoporous hydrogel for DNA preconcentration.

    Science.gov (United States)

    Kim, Hyoki; Kim, Junhoi; Kim, Eun-Geun; Heinz, Austen James; Kwon, Sunghoon; Chun, Honggu

    2010-12-30

    An optofluidic maskless photopolymerization process was developed for in situ negatively charged nanoporous hydrogel [poly-AMPS (2-acrylamido-2-methyl-1-propanesulfonic acid)] fabrication. The optofluidic maskless lithography system, which combines a high power UV source and digital mirror device, enables fast polymerization of arbitrary shaped hydrogels in a microfluidic device. The poly-AMPS hydrogel structures were positioned near the intersections of two microchannels, and were used as a cation-selective filter for biological sample preconcentration. Preconcentration dynamics as well as the fabricated polymer shape were analyzed in three-dimensions using fluorescein sample and a confocal microscope. Finally, single-stranded DNA preconcentration was demonstrated for polymerase chain reaction-free signal enhancement.

  1. Selective estrogen receptor modulators differentially alter the immune response of gilthead seabream juveniles.

    Science.gov (United States)

    Rodenas, M C; Cabas, I; García-Alcázar, A; Meseguer, J; Mulero, V; García-Ayala, A

    2016-05-01

    17α-ethynylestradiol (EE2), a synthetic estrogen used in oral contraceptives and hormone replacement therapy, tamoxifen (Tmx), a selective estrogen-receptor modulator used in hormone replacement therapy, and G1, a G protein-coupled estrogen receptor (GPER) selective agonist, differentially increased the hepatic vitellogenin (vtg) gene expression and altered the immune response in adult gilthead seabream (Sparus aurata L.) males. However, no information exists on the effects of these compounds on the immune response of juveniles. This study aims, for the first time, to investigate the effects of the dietary intake of EE2, Tmx or G1 on the immune response of gilthead seabream juveniles and the capacity of the immune system of the specimens to recover its functionality after ceasing exposures (recovery period). The specimens were immunized with hemocyanin in the presence of aluminium adjuvant 1 (group A) or 120 (group B) days after the treatments ceased (dpt). The results indicate that EE2 and Tmx, but not G1, differentially promoted a transient alteration in hepatic vtg gene expression. Although all three compounds did not affect the production of reactive oxygen intermediates, they inhibited the induction of interleukin-1β (il1b) gene expression after priming. Interestingly, although Tmx increased the percentage of IgM-positive cells in both head kidney and spleen during the recovery period, the antibody response of vaccinated fish varied depending on the compound used and when the immunization was administered. Taken together, our results suggest that these compounds differentially alter the capacity of fish to respond to infection during ontogeny and, more interestingly, that the adaptive immune response remained altered to an extent that depends on the compound.

  2. Mass, charge, and energy separation by selective acceleration with a traveling potential hill

    Science.gov (United States)

    Tung, L. Schwager; Barr, W. L.; Lowder, R. S.; Post, R. F.

    1996-10-01

    A traveling electric potential hill has been used to generate an ion beam with an energy distribution that is mass dependent from a monoenergetic ion beam of mixed masses. This effect can be utilized as a novel method for mass separation applied to identification or enrichment of ions (e.g., of elements, isotopes, or molecules). This theory for mass-selective acceleration is presented here and is shown to be confirmed by experiment and by a time-dependent particle-in-cell computer simulation. Results show that monoenergetic ions with the particular mass of choice are accelerated by controlling the hill potential and the hill velocity. The hill velocity is typically 20%-30% faster than the ions to be accelerated. The ability of the hill to pickup a particular mass uses the fact that small kinetic energy differences in the lab frame appear much larger in the moving hill frame. Ions will gain energy from the approaching hill if their relative energy in the moving hill frame is less than the peak potential of the hill. The final energy of these accelerated ions can be several times the source energy, which facilitates energy filtering for mass purification or identification. If the hill potential is chosen to accelerate multiple masses, the heaviest mass will have the greatest final energy. Hence, choosing the appropriate hill potential and collector retarding voltage will isolate ions with the lightest, heaviest, or intermediate mass. In the experimental device, called a Solitron, purified 20Ne and 22Ne are extracted from a ribbon beam of neon that is originally composed of 20Ne:22Ne in the natural ratio of 91:9. The isotopic content of the processed beam is determined by measuring the energy distribution of the detected current. These results agree with the theory. In addition to mass selectivity, our theory can also be applied to the filtration of an ion beam according to charge state or energy. Because of this variety of properties, the Solitron is envisioned to

  3. Non-selective Separation of Bacterial Cells with Magnetic Nanoparticles Facilitated by Varying Surface Charge

    Directory of Open Access Journals (Sweden)

    Xin-Lei Gao

    2016-12-01

    Full Text Available Recovering microorganisms from environmental samples is a crucial primary step for understanding microbial communities using molecular ecological approaches. It is often challenging to harvest microorganisms both efficiently and unselectively, guaranteeing a similar microbial composition between original and separated biomasses. A magnetic nanoparticles (MNPs based method was developed to effectively separate microbial biomass from glass fiber pulp entrapped bacteria. Buffering pH and nanoparticle silica encapsulation significantly affected both biomass recovery and microbial selectivity. Under optimized conditions (using citric acid coated Fe3O4, buffering pH=2.2, the method was applied in the pretreatment of TSP sampler collected bioaerosols, the effective volume for DNA extraction was increased 10-folds, and the overall method detection limit of microbial contaminants in bioaerosols significantly decreased. A consistent recovery of the majority of airborne bacterial populations was demonstrated by in-depth comparison of microbial composition using 16S rRNA gene high-throughput sequencing. Surface charge was shown as the deciding factor for the interaction between MNPs and microorganisms, which helps developing materials with high microbial selectivity. To our knowledge, this study is the first report using MNPs to separate diverse microbial community unselectively from a complex environmental matrix. The technique is convenient and sensitive, as well as feasible to apply in monitoring of microbial transport and other related fields.

  4. Selective alterations of transcription factors in MPP+-induced neurotoxicity in PC12 cells.

    Science.gov (United States)

    Xu, Z; Cawthon, D; McCastlain, K A; Duhart, H M; Newport, G D; Fang, H; Patterson, T A; Slikker, W; Ali, S F

    2005-08-01

    MPP(+) (1-methyl-4-phenylpyridinium; the active metabolite of the neurotoxin MPTP (1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine)) depletes dopamine (DA) content and elicits cell death in PC12 cells. However, the mechanism of MPP(+)-induced neurotoxicity is still unclear. In this study, the dose response and time-course of MPP(+)-induced DA depletion and decreased cell viability were determined in nerve growth factor (NGF)-differentiated PC12 cells. The alteration of transcription factors (TFs) induced by MPP(+) from a selected dose level and time point was then evaluated using protein/DNA-binding arrays. K-means clustering analysis identified four patterns of protein/DNA-binding changes. Three of the 28 TFs identified in PC12 cells increased by 100% (p53, PRE, Smad SBE) and 2 decreased by 50% (HSE, RXR(DR1)) of control with MPP(+) treatment. In addition, three TFs decreased within the range of 33-50% (TFIID, E2F1, CREB) and two TFs increased within the range of 50-100% (PAX-5, Stat4). An electrophoretic mobility shift assay (EMSA) was used to confirm the changes of p53 and HSE. The observed changes in TFs correlated with the alterations of DA and cell viability. The data indicates that selective transcription factors are involved in MPP(+)-induced neurotoxicity and it provides mechanistic information that may be applicable to animal studies with MPTP and clinical studies of Parkinson's disease.

  5. Charge inversion, water splitting, and vortex suppression due to DNA sorption on ion-selective membranes and their ion-current signatures.

    Science.gov (United States)

    Slouka, Zdenek; Senapati, Satyajyoti; Yan, Yu; Chang, Hsueh-Chia

    2013-07-02

    The physisorption of negatively charged single-stranded DNA (ssDNA) of different lengths onto the surface of anion-exchange membranes is sensitively shown to alter the anion flux through the membrane. At low surface concentrations, the physisorbed DNAs act to suppress an electroconvection vortex instability that drives the anion flux into the membrane and hence reduce the overlimiting current through the membrane. Beyond a critical surface concentration, determined by the total number of phosphate charges on the DNA, the DNA layer becomes a cation-selective membrane, and the combined bipolar membrane has a lower net ion flux, at low voltages, than the original membrane as a result of ion depletion at the junction between the cation- (DNA) and anion-selective membranes. However, beyond a critical voltage that is dependent on the ssDNA coverage, water splitting occurs at the junction to produce a larger overlimiting current than that of the original membrane. These two large opposite effects of polyelectrolyte counterion sorption onto membrane surfaces may be used to eliminate limiting current constraints of ion-selective membranes for liquid fuel cells, dialysis, and desalination as well as to suggest a new low-cost membrane surface assay that can detect and quantify the number of large biomolecules captured by probes functionalized on the membrane surface.

  6. Electrochemical analysis of the alterations in copper pigments using charge transfer coefficient/peak potential diagrams. Application to microsamples of baroque wall paintings attached to polymer film electrodes.

    Science.gov (United States)

    Doménech-Carbó, A; Doménech-Carbó, M T; Gimeno-Adelantado, J V; Bosch-Reig, F; Saurí-Peris, M C; Casas-Catalán, M J

    2001-04-01

    The alteration of copper pigments in art samples was studied by linear scan and cyclic voltammetry using sample-modified Elvacite 2044 film electrodes on the basis of two-dimensional diagrams of charge transfer coefficients calculated from Tafel plots of reductive dissolution processes vs. peak potential. Characteristic voltammetric peaks were obtained for pigments used in the baroque vault frescoes of the Basílica de la Virgen de los Desamparados painted by Antonio Palomino. Results obtained by voltammetric techniques were compared with those from SEM/EDX and FT-IR analysis obtaining a good agreement and leaving to an unambiguous identification of pigments used by Palomino and their alteration products.

  7. Altering the interfacial activation mechanism of a lipase by solid-phase selective chemical modification.

    Science.gov (United States)

    López-Gallego, Fernando; Abian, Olga; Guisán, Jose Manuel

    2012-09-04

    This study presents a combined protein immobilization, directed mutagenesis, and site-selective chemical modification approach, which was used to create a hyperactivated semisynthetic variant of BTL2. Various alkane chains were tethered at three different positions in order to mimic the lipase interfacial activation exogenously triggered by detergents. Optimum results were obtained when a dodecane chain was introduced at position 320 by solid-phase site-selective chemical modification. The resulting semisynthetic variant showed a 2.5-fold higher activity than the wild-type nonmodified variant in aqueous conditions. Remarkably, this is the maximum hyperactivation ever observed for BTL2 in the presence of detergents such as Triton X-100. We present evidence to suggest that the endogenous dodecane chain hyperactivates the enzyme in a similar fashion as an exogenous detergent molecule. In this way, we also observe a faster irreversible enzyme inhibition and an altered detergent sensitivity profile promoted by the site-selective chemical modification. These findings are also supported by fluorescence studies, which reveal that the structural conformation changes of the semisynthetic variant are different to those of the wild type, an effect that is more pronounced in the presence of detergent. Finally, the optimal immobilized semisynthetic variant was successfully applied to the selective synthesis of oxiran-2-yl butyrate. Significantly, this biocatalyst is 12-fold more efficient than the immobilized wild-type enzyme, producing the S-enantiomer with higher enantiospecificity (ee = 92%).

  8. Masting behaviour in a Mediterranean pine tree alters seed predator selection on reproductive output.

    Science.gov (United States)

    Moreira, X; Abdala-Roberts, L; Zas, R; Merlo, E; Lombardero, M J; Sampedro, L; Mooney, K A

    2016-11-01

    Context-dependency in species interactions is widespread and can produce concomitant patterns of context-dependent selection. Masting (synchronous production of large seed crops at irregular intervals by a plant population) has been shown to reduce seed predation through satiation (reduction in rates of seed predation with increasing seed cone output) and thus represents an important source of context-dependency in plant-animal interactions. However, the evolutionary consequences of such dynamics are not well understood. Here we describe masting behaviour in a Mediterranean model pine species (Pinus pinaster) and present a test of the effects of masting on selection by seed predators on reproductive output. We predicted that masting, by enhancing seed predator satiation, could in turn strengthen positive selection by seed predators for larger cone output. For this we collected six-year data (spanning one mast year and five non-mast years) on seed cone production and seed cone predation rates in a forest genetic trial composed by 116 P. pinaster genotypes. Following our prediction, we found stronger seed predator satiation during the masting year, which in turn led to stronger seed predator selection for increased cone production relative to non-masting years. These findings provide evidence that masting can alter the evolutionary outcome of plant-seed predator interactions. More broadly, our findings highlight that changes in consumer responses to resource abundance represent a widespread mechanism for predicting and understanding context dependency in plant-consumer evolutionary dynamics.

  9. The new ECR charge breeder for the Selective Production of Exotic Species project at INFN—Laboratori Nazionali di Legnaro

    Science.gov (United States)

    Galatà, A.; Patti, G.; Roncolato, C.; Angot, J.; Lamy, T.

    2016-02-01

    The Selective Production of Exotic Species (SPES) project is an ISOL facility under construction at Istituto Nazionale di Fisica Nucleare-Laboratori Nationali di Legnaro (INFN-LNL). 1+ radioactive ions, produced and extracted from the target-ion-source system, will be charge bred to high charge states by an ECR charge breeder (SPES-CB): the project will adopt an upgraded version of the PHOENIX charge breeder, developed since about twenty years by the Laboratoire de Physique Subatomique et de Cosmologie (LPSC). The collaboration between LNL and LPSC started in 2010 with charge breeding experiments performed on the LPSC test bench and led, in June 2014, to the signature of a Research Collaboration Agreement for the delivery of a complete charge breeder and ancillaries, satisfying the SPES requirements. Important technological aspects were tackled during the construction phase, as, for example, beam purity issues, electrodes alignment, and vacuum sealing. This phase was completed in spring 2015, after which the qualification tests were carried out at LPSC on the 1+/q+ test stand. This paper describes the characteristics of the SPES-CB, with particular emphasis on the results obtained during the qualification tests: charge breeding of Ar, Xe, Rb, and Cs satisfied the SPES requirements for different intensities of the injected 1+ beam, showing very good performances, some of which are "best ever" for this device.

  10. The new ECR charge breeder for the Selective Production of Exotic Species project at INFN—Laboratori Nazionali di Legnaro

    Energy Technology Data Exchange (ETDEWEB)

    Galatà, A., E-mail: alessio.galata@lnl.infn.it; Patti, G.; Roncolato, C. [INFN-Laboratori Nazionali di Legnaro, Viale dell’Università 2, 35020 Padova, Legnaro (Italy); Angot, J.; Lamy, T. [LPSC-Université Grenoble Alpes-CNRS/IN2P3, 53 rue des Martyrs, 38026 Grenoble CEDEX (France)

    2016-02-15

    The Selective Production of Exotic Species (SPES) project is an ISOL facility under construction at Istituto Nazionale di Fisica Nucleare–Laboratori Nationali di Legnaro (INFN-LNL). 1+ radioactive ions, produced and extracted from the target-ion-source system, will be charge bred to high charge states by an ECR charge breeder (SPES-CB): the project will adopt an upgraded version of the PHOENIX charge breeder, developed since about twenty years by the Laboratoire de Physique Subatomique et de Cosmologie (LPSC). The collaboration between LNL and LPSC started in 2010 with charge breeding experiments performed on the LPSC test bench and led, in June 2014, to the signature of a Research Collaboration Agreement for the delivery of a complete charge breeder and ancillaries, satisfying the SPES requirements. Important technological aspects were tackled during the construction phase, as, for example, beam purity issues, electrodes alignment, and vacuum sealing. This phase was completed in spring 2015, after which the qualification tests were carried out at LPSC on the 1+/q+ test stand. This paper describes the characteristics of the SPES-CB, with particular emphasis on the results obtained during the qualification tests: charge breeding of Ar, Xe, Rb, and Cs satisfied the SPES requirements for different intensities of the injected 1+ beam, showing very good performances, some of which are “best ever” for this device.

  11. Detectors for selective registration of charged particles and gamma-quanta

    CERN Document Server

    Ryzhikov, V; Katrunov, K

    2002-01-01

    A new design is proposed and described of a combined detector (CD) for simultaneous detection of charged particles and gamma-quanta. The CD comprises a single crystalline plate of ZnSe(Te) placed onto the output window of a scintillating transparent light transducer made of CsI(Ti) and Al sub 2 O sub 3 (Ti) in the shape of truncated pyramid. The CsI(Ti) light transducer is used to create an additional channel for detection of gamma-radiation,as well as for protecting the photodiode from the penetrating radiation.It is shown that introduction of such light transducer does not worsen the energy characteristics of ZnSe(Te). Separate detection of alpha- and gamma-radiation has been achieved under simultaneous excitation by sup 2 sup 3 sup 9 Pu (ZnSe(Te), R sub a =6%) and sup 2 sup 4 sup 1 Am (CsI(Tl), R subgamma = 20 %). The use of selective optical filters allows separation of the peaks of total absorption (p.t.a.) in the case of their superposition.

  12. Selective Surface Charge Sign Reversal on Metallic Carbon Nanotubes for Facile Ultrahigh Purity Nanotube Sorting.

    Science.gov (United States)

    Wang, Jing; Nguyen, Tuan Dat; Cao, Qing; Wang, Yilei; Tan, Marcus Y C; Chan-Park, Mary B

    2016-03-22

    Semiconducting (semi-) single-walled carbon nanotubes (SWNTs) must be purified of their metallic (met-) counterparts for most applications including nanoelectronics, solar cells, chemical sensors, and artificial skins. Previous bulk sorting techniques are based on subtle contrasts between properties of different nanotube/dispersing agent complexes. We report here a method which directly exploits the nanotube band structure differences. For the heterogeneous redox reaction of SWNTs with oxygen/water couple, the aqueous pH can be tuned so that the redox kinetics is determined by the availability of nanotube electrons only at/near the Fermi level, as predicted quantitatively by the Marcus-Gerischer (MG) theory. Consequently, met-SWNTs oxidize much faster than semi-SWNTs and only met-SWNTs selectively reverse the sign of their measured surface zeta potential from negative to positive at the optimized acidic pH when suspended with nonionic surfactants. By passing the redox-reacted nanotubes through anionic hydrogel beads, we isolate semi-SWNTs to record high electrically verified purity above 99.94% ± 0.04%. This facile charge sign reversal (CSR)-based sorting technique is robust and can sort SWNTs with a broad diameter range.

  13. Desired alteration of protein affinities: competitive selection of protein variants using yeast signal transduction machinery.

    Directory of Open Access Journals (Sweden)

    Misato Kaishima

    Full Text Available Molecules that can control protein-protein interactions (PPIs have recently drawn attention as new drug pipeline compounds. Here, we report a technique to screen desirable affinity-altered (affinity-enhanced and affinity-attenuated protein variants. We previously constructed a screening system based on a target protein fused to a mutated G-protein γ subunit (Gγcyto lacking membrane localization ability. This ability, required for signal transmission, is restored by recruiting Gγcyto into the membrane only when the target protein interacts with an artificially membrane-anchored candidate protein, thereby allowing interacting partners (Gγ recruitment system to be searched and identified. In the present study, the Gγ recruitment system was altered by integrating the cytosolic expression of a third protein as a competitor to set a desirable affinity threshold. This enabled the reliable selection of both affinity-enhanced and affinity-attenuated protein variants. The presented approach may facilitate the development of therapeutic proteins that allow the control of PPIs.

  14. Environmentally realistic exposure to the herbicide atrazine alters some sexually selected traits in male guppies.

    Directory of Open Access Journals (Sweden)

    Kausalya Shenoy

    Full Text Available Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments and the number of courtship displays performed. Atrazine exposure also reduced aggression towards competing males in the context of mate competition. In the wild, exposure levels vary among individuals because of differential distribution of the pollutants across habitats; hence, differently impacted males often compete for the same mates. Disrupted mating signals can reduce reproductive success as females avoid mating with perceptibly suboptimal males. Less aggressive males are at a competitive disadvantage and lose access to females. This study highlights the effects of atrazine on ecologically relevant mating signals and behaviors in exposed wildlife. Altered reproductive traits have important implications for population dynamics, evolutionary patterns, and conservation of wildlife species.

  15. Environmentally Realistic Exposure to the Herbicide Atrazine Alters Some Sexually Selected Traits in Male Guppies

    Science.gov (United States)

    Shenoy, Kausalya

    2012-01-01

    Male mating signals, including ornaments and courtship displays, and other sexually selected traits, like male-male aggression, are largely controlled by sex hormones. Environmental pollutants, notably endocrine disrupting compounds, can interfere with the proper functioning of hormones, thereby impacting the expression of hormonally regulated traits. Atrazine, one of the most widely used herbicides, can alter sex hormone levels in exposed animals. I tested the effects of environmentally relevant atrazine exposures on mating signals and behaviors in male guppies, a sexually dimorphic freshwater fish. Prolonged atrazine exposure reduced the expression of two honest signals: the area of orange spots (ornaments) and the number of courtship displays performed. Atrazine exposure also reduced aggression towards competing males in the context of mate competition. In the wild, exposure levels vary among individuals because of differential distribution of the pollutants across habitats; hence, differently impacted males often compete for the same mates. Disrupted mating signals can reduce reproductive success as females avoid mating with perceptibly suboptimal males. Less aggressive males are at a competitive disadvantage and lose access to females. This study highlights the effects of atrazine on ecologically relevant mating signals and behaviors in exposed wildlife. Altered reproductive traits have important implications for population dynamics, evolutionary patterns, and conservation of wildlife species. PMID:22312428

  16. Selective charging of tRNA isoacceptors induced by amino-acid starvation

    DEFF Research Database (Denmark)

    Dittmar, K. A.; Sørensen, Michael Askvad; Elf, J.

    2005-01-01

    Aminoacylated (charged) transfer RNA isoacceptors read different messenger RNA codons for the same amino acid. The concentration of an isoacceptor and its charged fraction are principal determinants of the translation rate of its codons. A recent theoretical model predicts that amino-acid starvat...

  17. Controlling the Charge State and Redox Properties of Supported Polyoxometalates via Soft Landing of Mass Selected Ions

    Energy Technology Data Exchange (ETDEWEB)

    Gunaratne, Kalupathirannehelage Don D.; Johnson, Grant E.; Andersen, Amity; Du, Dan; Zhang, Weiying; Prabhakaran, Venkateshkumar; Lin, Yuehe; Laskin, Julia

    2014-12-04

    We investigate the controlled deposition of Keggin polyoxometalate (POM) anions, PMo12O403- and PMo12O402-, onto different self-assembled monolayer (SAM) surfaces via soft landing of mass-selected ions. Utilizing in situ infrared reflection absorption spectroscopy (IRRAS), ex situ cyclic voltammetry (CV) and electronic structure calculations, we examine the structure and charge retention of supported multiply-charged POM anions and characterize the redox properties of the modified surfaces. SAMs of alkylthiol (HSAM), perfluorinated alkylthiol (FSAM), and alkylthiol terminated with NH3+ functional groups (NH3+SAM) are chosen as model substrates for soft landing to examine the factors which influence the immobilization and charge retention of multiply charged anionic molecules. The distribution of charge states of POMs on different SAM surfaces are determined by comparing the IRRAS spectra with vibrational spectra calculated using density functional theory (DFT). In contrast to the results obtained previously for multiply charged cations, soft landed anions are found to retain charge on all three SAM surfaces. This charge retention is attributed to the substantial electron binding energy of the POM anions. Investigation of redox properties by CV reveals that, while surfaces prepared by soft landing exhibit similar features to those prepared by adsorption of POM from solution, the soft landed POM2- has a pronounced shift in oxidation potential compared to POM3- for one of the redox couples. These results demonstrate that ion soft landing is uniquely suited for precisely controlled preparation of substrates with specific electronic and chemical properties that cannot be achieved using conventional deposition techniques.

  18. Angiogenic Signalling Pathways Altered in Gliomas: Selection Mechanisms for More Aggressive Neoplastic Subpopulations with Invasive Phenotype

    Directory of Open Access Journals (Sweden)

    Susana Bulnes

    2012-01-01

    Full Text Available The angiogenesis process is a key event for glioma survival, malignancy and growth. The start of angiogenesis is mediated by a cascade of intratumoural events: alteration of the microvasculature network; a hypoxic microenvironment; adaptation of neoplastic cells and synthesis of pro-angiogenic factors. Due to a chaotic blood flow, a consequence of an aberrant microvasculature, tissue hypoxia phenomena are induced. Hypoxia inducible factor 1 is a major regulator in glioma invasiveness and angiogenesis. Clones of neoplastic cells with stem cell characteristics are selected by HIF-1. These cells, called “glioma stem cells” induce the synthesis of vascular endothelial growth factor. This factor is a pivotal mediator of angiogenesis. To elucidate the role of these angiogenic mediators during glioma growth, we have used a rat endogenous glioma model. Gliomas induced by prenatal ENU administration allowed us to study angiogenic events from early to advanced tumour stages. Events such as microvascular aberrations, hypoxia, GSC selection and VEGF synthesis may be studied in depth. Our data showed that for the treatment of gliomas, developing anti-angiogenic therapies could be aimed at GSCs, HIF-1 or VEGF. The ENU-glioma model can be considered to be a useful option to check novel designs of these treatment strategies.

  19. Angiogenic Signalling Pathways Altered in Gliomas: Selection Mechanisms for More Aggressive Neoplastic Subpopulations with Invasive Phenotype

    Science.gov (United States)

    Bulnes, Susana; Bengoetxea, Harkaitz; Ortuzar, Naiara; Argandoña, Enrike G.; Garcia-Blanco, Álvaro; Rico-Barrio, Irantzu; Lafuente, José V.

    2012-01-01

    The angiogenesis process is a key event for glioma survival, malignancy and growth. The start of angiogenesis is mediated by a cascade of intratumoural events: alteration of the microvasculature network; a hypoxic microenvironment; adaptation of neoplastic cells and synthesis of pro-angiogenic factors. Due to a chaotic blood flow, a consequence of an aberrant microvasculature, tissue hypoxia phenomena are induced. Hypoxia inducible factor 1 is a major regulator in glioma invasiveness and angiogenesis. Clones of neoplastic cells with stem cell characteristics are selected by HIF-1. These cells, called “glioma stem cells” induce the synthesis of vascular endothelial growth factor. This factor is a pivotal mediator of angiogenesis. To elucidate the role of these angiogenic mediators during glioma growth, we have used a rat endogenous glioma model. Gliomas induced by prenatal ENU administration allowed us to study angiogenic events from early to advanced tumour stages. Events such as microvascular aberrations, hypoxia, GSC selection and VEGF synthesis may be studied in depth. Our data showed that for the treatment of gliomas, developing anti-angiogenic therapies could be aimed at GSCs, HIF-1 or VEGF. The ENU-glioma model can be considered to be a useful option to check novel designs of these treatment strategies. PMID:22852079

  20. Post-duplication charge evolution of phosphoglucose isomerases in teleost fishes through weak selection on many amino acid sites

    Directory of Open Access Journals (Sweden)

    Sato Yukuto

    2007-10-01

    Full Text Available Abstract Background The partitioning of ancestral functions among duplicated genes by neutral evolution, or subfunctionalization, has been considered the primary process for the evolution of novel proteins (neofunctionalization. Nonetheless, how a subfunctionalized protein can evolve into a more adaptive protein is poorly understood, mainly due to the limitations of current analytical methods, which can detect only strong selection for amino acid substitutions involved in adaptive molecular evolution. In this study, we employed a comparative evolutionary approach to this question, focusing on differences in the structural properties of a protein, specifically the electric charge, encoded by fish-specific duplicated phosphoglucose isomerase (Pgi genes. Results Full-length cDNA cloning, RT-PCR based gene expression analyses, and comparative sequence analyses showed that after subfunctionalization with respect to the expression organ of duplicate Pgi genes, the net electric charge of the PGI-1 protein expressed mainly in internal tissues became more negative, and that of PGI-2 expressed mainly in muscular tissues became more positive. The difference in net protein charge was attributable not to specific amino acid sites but to the sum of various amino acid sites located on the surface of the PGI molecule. Conclusion This finding suggests that the surface charge evolution of PGI proteins was not driven by strong selection on individual amino acid sites leading to permanent fixation of a particular residue, but rather was driven by weak selection on a large number of amino acid sites and consequently by steady directional and/or purifying selection on the overall structural properties of the protein, which is derived from many modifiable sites. The mode of molecular evolution presented here may be relevant to various cases of adaptive modification in proteins, such as hydrophobic properties, molecular size, and electric charge.

  1. Free-Electron Laser Wavelength-Selective Materials Alteration and Photoexcitation Spectroscopy

    Science.gov (United States)

    Tolk, Norman.

    1996-10-01

    The Vanderbilt Free-Electron Laser's (FEL) tunability (2-10um), high intensity (15 MW) and short pulse structure (1 ps) make it ideal for studying (a) the electronic and vibrational structure of small and wide band gap semiconductors, and (b) non-thermal wavelength-selective materials alteration. Spectroscopic studies footnote Work performed with R.G. Albridge, A.V. Barnes, J. Gilligan, G. Margaritondo, and J. T. McKinley of semiconductor electronic and nonlinear optical properties will be discussed. Recent two-photon absorption measurements in Ge were the first verification of a two-decades old prediction by Bassani and Hassan that the indirect two-photon absorption in Ge would be an LO-phonon assisted process. They also provided valuable insight into the effect of inversion symmetry on two-photon absorption. The strength of germanium's indirect gap two-photon absorption was found to be 1000 times weaker than the direct absorption. The FEL has greatly facilitated internal photoemission (IPE) heterojunction band discontinuity measurements. This technique is a photocurrent excitation spectroscopy that provides a direct measurement of the discontinuity without resorting to complex modeling. A photocurrent threshold is observed as the photon energy exceeds the discontinuity energy. IPE has long been used in the field of Schottky barriers but has largely been ignored in the case of semiconductor heterojunctions because of insufficiently intense light sources. We will discuss IPE measurements of InP/GaInAs and a-Ge/GaAs. Our low-temperature IPE discontinuity measurements reach accuracies better than #5 meV. Another important area of materials research at the FEL concerns identification of wavelength-selective mechanisms for materials alteration. Vibrational modes associated with defects and impurities provide a means of introducing a non thermal distribution of energy into a solid. We have used the FEL to demonstrate strongly wavelength-selective ablation near the C

  2. High-energy Electron Scattering and the Charge Distributions of Selected Nuclei

    Science.gov (United States)

    Hahn, B.; Ravenhall, D. G.; Hofstadter, R.

    1955-10-01

    Experimental results are presented of electron scattering by Ca, V, Co, In, Sb, Hf, Ta, W, Au, Bi, Th, and U, at 183 Mev and (for some of the elements) at 153 Mev. For those nuclei for which asphericity and inelastic scattering are absent or unimportant, i.e., Ca, V, Co, In, Sb, Au, and Bi, a partial wave analysis of the Dirac equation has been performed in which the nuclei are represented by static, spherically symmetric charge distributions. Smoothed uniform charge distributions have been assumed; these are characterized by a constant charge density in the central region of the nucleus, with a smoothed-our surface. Essentially two parameters can be determined, related to the radium and to the surface thickness. An examination of the Au experiments show that the functional forms of the surface are not important, and that the charge density in the central regions is probably fairly flat, although it cannot be determined very accurately.

  3. Acute stress alters auditory selective attention in humans independent of HPA: a study of evoked potentials.

    Directory of Open Access Journals (Sweden)

    Ludger Elling

    Full Text Available BACKGROUND: Acute stress is a stereotypical, but multimodal response to a present or imminent challenge overcharging an organism. Among the different branches of this multimodal response, the consequences of glucocorticoid secretion have been extensively investigated, mostly in connection with long-term memory (LTM. However, stress responses comprise other endocrine signaling and altered neuronal activity wholly independent of pituitary regulation. To date, knowledge of the impact of such "paracorticoidal" stress responses on higher cognitive functions is scarce. We investigated the impact of an ecological stressor on the ability to direct selective attention using event-related potentials in humans. Based on research in rodents, we assumed that a stress-induced imbalance of catecholaminergic transmission would impair this ability. METHODOLOGY/PRINCIPAL FINDINGS: The stressor consisted of a single cold pressor test. Auditory negative difference (Nd and mismatch negativity (MMN were recorded in a tonal dichotic listening task. A time series of such tasks confirmed an increased distractibility occurring 4-7 minutes after onset of the stressor as reflected by an attenuated Nd. Salivary cortisol began to rise 8-11 minutes after onset when no further modulations in the event-related potentials (ERP occurred, thus precluding a causal relationship. This effect may be attributed to a stress-induced activation of mesofrontal dopaminergic projections. It may also be attributed to an activation of noradrenergic projections. Known characteristics of the modulation of ERP by different stress-related ligands were used for further disambiguation of causality. The conjuncture of an attenuated Nd and an increased MMN might be interpreted as indicating a dopaminergic influence. The selective effect on the late portion of the Nd provides another tentative clue for this. CONCLUSIONS/SIGNIFICANCE: Prior studies have deliberately tracked the adrenocortical influence

  4. Selected clinical, biochemical, and electrolyte alterations in anesthetized captive tigers (Panthera tigris) and lions (Panthera leo).

    Science.gov (United States)

    Reilly, Sabrina; Seddighi, M Reza; Steeil, James C; Sura, Patricia; Whittemore, Jacqueline C; Gompf, Rebecca E; Elliott, Sarah B; Ramsay, Edward C

    2014-06-01

    A prospective study to assess changes in selected plasma biochemistry and electrolyte values, plasma insulin and aldosterone concentrations, and electrocardiography (ECG) was performed on eight female captive tigers (Panthera tigris) and three lions (Panthera leo) undergoing general anesthesia for elective laparoscopic ovariectomy. Each animal was sedated with medetomidine (18-25 microg/kg) and midazolam (0.06-0.1 mg/kg) intramuscularly, and anesthesia was induced with ketamine (1.9-3.5 mg/kg) intramuscularly and maintained with isoflurane. Venous blood samples were collected and analyzed for plasma biochemistry parameters and insulin and aldosterone concentrations. An ECG was recorded at the time of each blood sample collection. Mean plasma potassium, glucose, phosphorus, and aldosterone concentrations increased during anesthesia (P < or = 0.05). One tiger developed hyperkalemia (6.5 mmol/L) 2.5 hr after anesthetic induction. Plasma insulin concentrations were initially below the low end of the domestic cat reference interval (72-583 pmol/L), but mean insulin concentration increased (P < or = 0.05) over time compared with the baseline values. Three tigers and two lions had ECG changes that were representative of myocardial hypoxemia. Based on these results, continuous monitoring of clinical and biochemical alterations during general anesthesia in large nondomestic felids is warranted, and consideration should be given to reversal of medetomidine in these animals should significant changes in electrolytes or ECG occur.

  5. Zeta Sperm Selection Improves Pregnancy Rate and Alters Sex Ratio in Male Factor Infertility Patients: A Double-Blind, Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Nasr Esfahani Mohammad Hossein

    2016-07-01

    Full Text Available Background Selection of sperm for intra-cytoplasmic sperm injection (ICSI is usually considered as the ultimate technique to alleviate male-factor infertility. In routine ICSI, selection is based on morphology and viability which does not necessarily preclude the chance injection of DNA-damaged or apoptotic sperm into the oocyte. Sperm with high negative surface electrical charge, named “Zeta potential”, are mature and more likely to have intact chromatin. In addition, X-bearing spermatozoa carry more negative charge. Therefore, we aimed to compare the clinical outcomes of Zeta procedure with routine sperm selection in infertile men candidate for ICSI. Materials and Methods From a total of 203 ICSI cycles studied, 101 cycles were allocated to density gradient centrifugation (DGC/Zeta group and the remaining 102 were included in the DGC group in this prospective study. Clinical outcomes were com- pared between the two groups. The ratios of Xand Y bearing sperm were assessed by fluorescence in situ hybridization (FISH and quantitative polymerase chain reaction (qPCR methods in 17 independent semen samples. Results In the present double-blind randomized clinical trial, a significant increase in top quality embryos and pregnancy rate were observed in DGC/Zeta group compared to DGC group. Moreover, sex ratio (XY/XX at birth significantly was lower in the DGC/Zeta group compared to DGC group despite similar ratio of X/Y bearings sper- matozoa following Zeta selection. Conclusion Zeta method not only improves the percentage of top embryo quality and pregnancy outcome but also alters the sex ratio compared to the conventional DGC method, despite no significant change in the ratio of Xand Ybearing sperm population (Registration number: IRCT201108047223N1.

  6. STN1 OB Fold Mutation Alters DNA Binding and Affects Selective Aspects of CST Function

    Science.gov (United States)

    Bhattacharjee, Anukana; Stewart, Jason; Chaiken, Mary; Price, Carolyn M.

    2016-01-01

    Mammalian CST (CTC1-STN1-TEN1) participates in multiple aspects of telomere replication and genome-wide recovery from replication stress. CST resembles Replication Protein A (RPA) in that it binds ssDNA and STN1 and TEN1 are structurally similar to RPA2 and RPA3. Conservation between CTC1 and RPA1 is less apparent. Currently the mechanism underlying CST action is largely unknown. Here we address CST mechanism by using a DNA-binding mutant, (STN1 OB-fold mutant, STN1-OBM) to examine the relationship between DNA binding and CST function. In vivo, STN1-OBM affects resolution of endogenous replication stress and telomere duplex replication but telomeric C-strand fill-in and new origin firing after exogenous replication stress are unaffected. These selective effects indicate mechanistic differences in CST action during resolution of different replication problems. In vitro binding studies show that STN1 directly engages both short and long ssDNA oligonucleotides, however STN1-OBM preferentially destabilizes binding to short substrates. The finding that STN1-OBM affects binding to only certain substrates starts to explain the in vivo separation of function observed in STN1-OBM expressing cells. CST is expected to engage DNA substrates of varied length and structure as it acts to resolve different replication problems. Since STN1-OBM will alter CST binding to only some of these substrates, the mutant should affect resolution of only a subset of replication problems, as was observed in the STN1-OBM cells. The in vitro studies also provide insight into CST binding mechanism. Like RPA, CST likely contacts DNA via multiple OB folds. However, the importance of STN1 for binding short substrates indicates differences in the architecture of CST and RPA DNA-protein complexes. Based on our results, we propose a dynamic DNA binding model that provides a general mechanism for CST action at diverse forms of replication stress. PMID:27690379

  7. Direct Observation of Charge Separation on Anatase TiO2 Crystals with Selectively Etched {001} Facets.

    Science.gov (United States)

    Liu, Xiaogang; Dong, Guojun; Li, Shaopeng; Lu, Gongxuan; Bi, Yingpu

    2016-03-09

    Synchronous illumination X-ray photoelectron spectroscopy (SIXPS) was employed for the first time to directly identify the photogenerated charge separation and transfer on anatase TiO2 single-crystals with selectively etched {001} facets. More specifically, for the TiO2 crystals with intact {001} and {101} facets, most of photogenerated charge carriers rapidly recombined, and no evident electron-hole separation was detected. With selectively etching on {001} facets, high efficient charge separation via hole transfer to titanium and electron to oxygen was clearly observed. However, when the {001} facets were completely etched into a hollow structure, the recombination for photogenerated electron-hole pairs would dominate again. These demonstrations clearly reveal that the appropriate corrosion on {001} facets could facilitate more efficient electron-hole separation and transfer. As expected, the optimized TiO2 microcrystals with etched {001} facets could achieve a hydrogen generation rate of 74.3 μmol/h/g, which is nearly 7 times higher than the intact-TiO2 crystals.

  8. THE POSSIBILITIES OF CO2 EMISSION REDUCTION IN THE PROCESS OF STEEL CHARGE HEATING THROUGH THE SELECTION OF HEATING RATE

    Directory of Open Access Journals (Sweden)

    Barbara Halusiak

    2015-08-01

    Full Text Available The reduction of carbon dioxide emission is an important aspect of the economic policy of each country. Institutions promoting environmental protection seek to reduce the level of greenhouse gas emissions. One of the main emitters of harmful gases to the atmosphere is the steelmaking sector. The heating technology used in metallurgical works contributes to the amount of emitted carbon dioxide that forms as a result of the loss of steel and the combustion of fuel, whose thermal energy is used during the course of the charge heating process in the heating furnace. Achieving the imposed ecological targets by not exceeding the specified emission level is possible by implementing appropriate pollutant emission reducing technologies in the metallurgical industry. Based on numerical computation results, the effect of heating rate on the emission of carbon dioxide has been determined in the paper. This study demonstrates that by selecting the appropriate steel charge heating technology the emissions of greenhouse gases can be substantially reduced.

  9. Optofluidic in situ maskless lithography of charge selective nanoporous hydrogel for DNA preconcentration

    OpenAIRE

    2010-01-01

    An optofluidic maskless photopolymerization process was developed for in situ negatively charged nanoporous hydrogel [poly-AMPS (2-acrylamido-2-methyl-1-propanesulfonic acid)] fabrication. The optofluidic maskless lithography system, which combines a high power UV source and digital mirror device, enables fast polymerization of arbitrary shaped hydrogels in a microfluidic device. The poly-AMPS hydrogel structures were positioned near the intersections of two microchannels, and were used as a ...

  10. Evidence of changes in renal charge selectivity in patients with type 1 (insulin-dependent) diabetes mellitus

    DEFF Research Database (Denmark)

    Kverneland, A; Feldt-Rasmussen, B; Vidal, P

    1986-01-01

    in plasma and urine was determined by a specific, sensitive and highly reproducible chromatographic procedure. In diabetic patients with normal urinary albumin excretion, the selectivity index was increased three-fold compared with that of non-diabetic subjects (2 p less than 0.01). A significant...... patients with increased albumin excretion rate had a significantly lower selectivity index compared with patients with normal albumin excretion (2 p less than 0.01). A significant negative correlation (r = 0.85, 2 p less than 0.001, exponential curve fit) was seen between urinary albumin excretion...... and selectivity index in the diabetic patients, indicating that the capability of differentiating between macromolecules of different charges is again lost with increasing urinary albumin excretion.(ABSTRACT TRUNCATED AT 250 WORDS)...

  11. Biochemical evaluation of a 108-member deglycobleomycin library: viability of a selection strategy for identifying bleomycin analogues with altered properties.

    Science.gov (United States)

    Ma, Qian; Xu, Zhidong; Schroeder, Benjamin R; Sun, Wenyue; Wei, Fang; Hashimoto, Shigeki; Konishi, Kazuhide; Leitheiser, Christopher J; Hecht, Sidney M

    2007-10-17

    The bleomycins (BLMs) are clinically used glycopeptide antitumor antibiotics that have been shown to mediate the sequence-selective oxidative damage of both DNA and RNA. Previously, we described the solid-phase synthesis of a library of 108 unique analogues of deglycoBLM A6, a congener that cleaves DNA analogously to BLM itself. Each member of the library was assayed for its ability to effect single- and double-strand nicking of duplex DNA, sequence-selective DNA cleavage, and RNA cleavage in the presence and absence of a metal ion cofactor. All of the analogues tested were found to mediate concentration-dependent plasmid DNA relaxation to some extent, and a number exhibited double-strand cleavage with an efficiency comparable to or greater than deglycoBLM A6. Further, some analogues having altered linker and metal-binding domains mediated altered sequence-selective cleavage, and a few were found to cleave a tRNA3Lys transcript both in the presence and in the absence of a metal cofactor. The results provide insights into structural elements within BLM that control DNA and RNA cleavage. The present study also permits inferences to be drawn regarding the practicality of a selection strategy for the solid-phase construction and evaluation of large libraries of BLM analogues having altered properties.

  12. The charge breeder beam line for the selective production of exotic species project at INFN-Legnaro National Laboratories

    Science.gov (United States)

    Galatà, A.; Comunian, M.; Maggiore, M.; Manzolaro, M.; Angot, J.; Lamy, T.

    2014-02-01

    SPES (Selective Production of Exotic Species) is an INFN (Istituto Nazionale di Fisica Nucleare) project with the aim at producing and post-accelerating exotic beams to perform forefront research in nuclear physics. To allow post-acceleration of the radioactive ions, an ECR-based Charge Breeder (CB) developed on the basis of the Phoenix booster was chosen. The design of the complete beam line for the SPES-CB will be described: a system for stable 1+ beams production was included; special attention was paid to the medium resolution mass spectrometer after the CB to limit possible superposition of the exotic beams with the impurities present in the ECR plasma.

  13. Conical intersections, charge localization, and photoisomerization pathway selection in a minimal model of a degenerate monomethine dye.

    Science.gov (United States)

    Olsen, Seth; McKenzie, Ross H

    2009-12-21

    We propose a minimal model Hamiltonian for the electronic structure of a monomethine dye, in order to describe the photoisomerization of such dyes. The model describes interactions between three diabatic electronic states, each of which can be associated with a valence bond structure. Monomethine dyes are characterized by a charge-transfer resonance; the indeterminacy of the single-double bonding structure dictated by the resonance is reflected in a duality of photoisomerization pathways corresponding to the different methine bonds. The possible multiplicity of decay channels complicates mechanistic models of the effect of the environment on fluorescent quantum yields, as well as coherent control strategies. We examine the extent and topology of intersection seams between the electronic states of the dye and how they relate to charge localization and selection between different decay pathways. We find that intersections between the S(1) and S(0) surfaces only occur for large twist angles. In contrast, S(2)/S(1) intersections can occur near the Franck-Condon region. When the molecule has left-right symmetry, all intersections are associated with con- or disrotations and never with single bond twists. For asymmetric molecules (i.e., where the bridge couples more strongly to one end) the S(2) and S(1) surfaces bias torsion about different bonds. Charge localization and torsion pathway biasing are correlated. We relate our observations with several recent experimental and theoretical results, which have been obtained for dyes with similar structure.

  14. Soft Landing of Mass-Selected Gold Clusters: Influence of Ion and Ligand on Charge Retention and Reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Grant E.; Laskin, Julia

    2015-02-01

    Herein, we employ a combination of reduction synthesis in solution, soft landing of mass-selected precursor and product ions, and in situ time-of-flight secondary ion mass spectrometry (TOF-SIMS) to examine the influence of ion and the length of diphosphine ligands on the charge retention and reactivity of ligated gold clusters deposited onto self-assembled monolayer surfaces (SAMs). Product ions (Au10L42+, (10,4)2+, L = 1,3-bis(diphenyl-phosphino)propane, DPPP) were prepared through in-source collision induced dissociation (CID) and precursor ions [(8,4)2+, L = 1,6-bis(diphenylphosphino)hexane, DPPH] were synthesized in solution for comparison to (11,5)3+ precursor ions ligated with DPPP investigated previously (ACS Nano 2012, 6, 573 and J. Phys. Chem. C. 2012, 116, 24977). Similar to (11,5)3+ precursor ions, the (10,4)2+ product ions are shown to retain charge on 1H,1H,2H,2H-perfluorodecanethiol monolayers (FSAMs). Additional abundant peaks at higher m/z indicative of reactivity are observed in the TOF-SIMS spectrum of (10,4)2+ product ions that are not seen for (11,5)3+ precursor ions. The abundance of (10,4)2+ on 16-mercaptohexadecanoic acid (COOH-SAMs) is demonstrated to be lower than on FSAMs, consistent with partial reduction of charge. The (10,4)2+ product ion on 1-dodecanethiol (HSAMs) exhibits peaks similar to those seen on the COOH-SAM. On the HSAM, higher m/z peaks indicative of reactivity are observed similar to those on the FSAM. The (8,4)2+ DPPH precursor ions are shown to retain charge on FSAMs similar to (11,5)3+ precursor ions prepared with DPPP. An additional peak corresponding to attachment of one gold atom to (8,4)2+ is observed at higher m/z for DPPH-ligated clusters. On the COOH-SAM, (8,4)2+ is less abundant than on the FSAM consistent with partial neutralization. The results indicate that although retention of charge by product ions generated by CID is similar to precursor ions their reactivity during analysis with SIMS is different

  15. Altering the self-organization of dyes on titania with dyeing solvents to tune the charge-transfer dynamics of sensitized solar cells.

    Science.gov (United States)

    Wang, Yinglin; Yang, Lin; Zhang, Jing; Li, Renzhi; Zhang, Min; Wang, Peng

    2014-04-14

    Herein we selected the model organic donor-acceptor dye C218 and modulated the self-organization of dye molecules on the surface of titania by changing the dyeing solvent from chlorobenzene to a mixture of acetonitrile and tert-butanol. We further unveiled the relationship between the microstructure of a dye layer and the multichannel charge-transfer dynamics that underlie the photovoltaic performance of dye-sensitized solar cells. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Natural soil microbes alter flowering phenology and the intensity of selection on flowering time in a wild Arabidopsis relative.

    Science.gov (United States)

    Wagner, Maggie R; Lundberg, Derek S; Coleman-Derr, Devin; Tringe, Susannah G; Dangl, Jeffery L; Mitchell-Olds, Thomas

    2014-06-01

    Plant phenology is known to depend on many different environmental variables, but soil microbial communities have rarely been acknowledged as possible drivers of flowering time. Here, we tested separately the effects of four naturally occurring soil microbiomes and their constituent soil chemistries on flowering phenology and reproductive fitness of Boechera stricta, a wild relative of Arabidopsis. Flowering time was sensitive to both microbes and the abiotic properties of different soils; varying soil microbiota also altered patterns of selection on flowering time. Thus, soil microbes potentially contribute to phenotypic plasticity of flowering time and to differential selection observed between habitats. We also describe a method to dissect the microbiome into single axes of variation that can help identify candidate organisms whose abundance in soil correlates with flowering time. This approach is broadly applicable to search for microbial community members that alter biological characteristics of interest.

  17. Controlled Assembly of Heterobinuclear Sites on Mesoporous Silica: Visible Light Charge-Transfer Units with Selectable Redox Properties

    Energy Technology Data Exchange (ETDEWEB)

    Frei, Heinz; Han, Hongxian; Frei, Heinz

    2008-06-04

    Mild synthetic methods are demonstrated for the selective assembly of oxo-bridged heterobinuclear units of the type TiOCrIII, TiOCoII, and TiOCeIII on mesoporous silica support MCM-41. One method takes advantage of the higher acidity and, hence, higher reactivity of titanol compared to silanol OH groups towards CeIII or CoII precursor. The procedure avoids the customary use of strong base. The controlled assembly of the TiOCr system exploits the selective redox reactivity of one metal towards another (TiIII precursor reacting with anchored CrVI centers). The observed selectivity for linking a metal precursor to an already anchored partner versus formation of isolated centers ranges from a factor of six (TiOCe) to complete (TiOCr, TiOCo). Evidence for oxo bridges and determination of the coordination environment of each metal centers is based on K-edge EXAFS (TiOCr), L-edge absorption spectroscopy (Ce), and XANES measurements (Co, Cr). EPR, optical, FT-Raman and FT-IR spectroscopy furnish additional details on oxidation state and coordination environment of donor and acceptor metal centers. In the case of TiOCr, the integrity of the anchored group upon calcination (350 oC) and cycling of the Cr oxidation state is demonstrated. The binuclear units possess metal-to-metal charge-transfer transitions that absorb deep in the visible region. The flexible synthetic method for assembling the units opens up the use of visible light charge transfer pumps featuring donor or acceptor metals with selectable redox potential.

  18. Mutagenesis of squash (Cucurbita moschata) glycerol-3-phosphate acyltransferase (GPAT) to produce an enzyme with altered substrate selectivity.

    Science.gov (United States)

    Hayman, M W; Fawcett, T; Schierer, T F; Simon, J W; Kroon, J T; Gilroy, J S; Rice, D W; Rafferty, J; Turnbull, A P; Sedelnikova, S E; Slabas, A R

    2000-12-01

    In an attempt to rationalize the relationship between structure and substrate selectivity of glycerol-3-phosphate acyltransferase (GPAT, 1AT, EC 2.3.1.15) we have cloned a number of cDNAs into the pET overexpression system using a PCR-based approach. Following assay of the recombinant enzyme we noted that the substrate selectivity of the squash (Cucurbita moschata) enzyme had altered dramatically. This form of GPAT has now been crystallized and its full three-dimensional structure elucidated. Since we now have two forms of the enzyme that display different substrate selectivities this should provide a powerful tool to determine the basis of the selectivity changes. Kinetic and structural analyses are currently being performed to rationalize the changes which have taken place.

  19. Enhanced conduction and minimized charge trapping in electrically alterable read-only memories using off-stoichiometric silicon dioxide films

    Science.gov (United States)

    Dimaria, D. J.; Dong, D. W.; Pesavento, F. L.; Lam, C.; Brorson, S. D.

    1984-04-01

    DiMaria et al. (1982) have published preliminary results related to the development of a solid-state nonvolatile random-access memory (NVRAM). It must be possible to change the information storage of such a memory very rapidly (approximately equal to or less than 1 microsecond). Such a memory is evolving from a mixed-phase oxide technology involving SiO2 and Si-rich SiO2 originally developed for a much slower memory (aproximately equal to or greater than 1 msec), called an electrically alterable read-only memory (EAROM). This article has the objective to present detailed information on the physics and on the operation of these memory devices. The original EAROM involved a field-effect-transistor (FET) configuration with a dual-electron-injector structure (DEIS). This memory was called a DEIS EAROM. The development of a modified DEIS EAROM (MDEIS EAROM) is discussed. The presented data provides more information on a new technical direction in the quest for a pure NVRAM.

  20. Effects of Rhythmic and Melodic Alterations and Selected Musical Experiences on Rhythmic Processing.

    Science.gov (United States)

    Sink, Patricia E.

    1984-01-01

    Study showed that music listening habits and preferences and instrument training may affect ways an individual processes the multiple dimensions of rhythm. Apparent alterations in tempo, duration and pitch characteristics, rhythmic and melodic phrase patterning, and monotony may serve as organizers of rhythmic processing. (Author/RM)

  1. STATE-SELECTIVE CHARGE-TRANSFER BETWEEN HE-LIKE IONS AND HE

    NARCIS (Netherlands)

    BEIJERS, JPM; HOEKSTRA, R; MORGENSTERN, R

    1994-01-01

    We report absolute, state-selective cross sections for single-electron capture by He-like ions (N5+, O6+, F7+, Ne8+) colliding on He which were determined by vuv photon-emission spectroscopy. The impact energy was varied between 0.05 and 2 keV amu(-1) The experimental data are compared with theoreti

  2. First state selective electron capture measurements with trapped highly charged ions

    NARCIS (Netherlands)

    Bliek, F.W.; Woestenenk, G.R.; Hoekstra, R.A.; Morgenstern, R.W.H.

    1997-01-01

    The first state selective electron capture cross section measurements at eV energies are reported for collisions between C4+ ions and H-2 molecules. The cross sections are measured in a crossed beam experiment by means of Photon Emission Spectroscopy. The ion beams are decelerated in an octopole ion

  3. Optimal Site Selection of Electric Vehicle Charging Stations Based on a Cloud Model and the PROMETHEE Method

    Directory of Open Access Journals (Sweden)

    Yunna Wu

    2016-03-01

    Full Text Available The task of site selection for electric vehicle charging stations (EVCS is hugely important from the perspective of harmonious and sustainable development. However, flaws and inadequacies in the currently used multi-criteria decision making methods could result in inaccurate and irrational decision results. First of all, the uncertainty of the information cannot be described integrally in the evaluation of the EVCS site selection. Secondly, rigorous consideration of the mutual influence between the various criteria is lacking, which is mainly evidenced in two aspects: one is ignoring the correlation, and the other is the unconscionable measurements. Last but not least, the ranking method adopted in previous studies is not very appropriate for evaluating the EVCS site selection problem. As a result of the above analysis, a Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE method-based decision system combined with the cloud model is proposed in this paper for EVCS site selection. Firstly, the use of the PROMETHEE method can bolster the confidence and visibility for decision makers. Secondly, the cloud model is recommended to describe the fuzziness and randomness of linguistic terms integrally and accurately. Finally, the Analytical Network Process (ANP method is adopted to measure the correlation of the indicators with a greatly simplified calculation of the parameters and the steps required.

  4. Calculations of state-selective differential cross sections for charge transfer in collisions between O3+ and H2

    Institute of Scientific and Technical Information of China (English)

    Chi Bao-Qian; Liu Ling; Wang Jian-Guo

    2008-01-01

    The non-dissociative charge-transfer processes in collisions between O3+ and H2 are investigated by using the quantum-mechanical molecular-orbital coupled-channel (QMOCC) method. The adiabatic potentials and radial cou-pling matrix elements.utilized in the QMOCC calculations are obtained with the spin-coupled valence-bond approach. Electronic and vibrational state-selective differential cross sections are presented for projectile energies of 0.1, 1.0 and 10.0 eV/u in the H2 orientation angles of 45° and 89°. The electronic and the vibrational state-selective differential cross sections show similar behaviours: they decrease as the scattering angle increases, and beyond a specific angle the oscillating structures appear. Moreover, it is also found that the vibrational state-selective differential cross sections are strongly orientation-dependent, which provides a possibility to determine the orientations of molecule H2 by identifying the vibrational state-selective differential scattering processes.

  5. Selective blockade of TRPA1 channel attenuates pathological pain without altering noxious cold sensation or body temperature regulation.

    Science.gov (United States)

    Chen, Jun; Joshi, Shailen K; DiDomenico, Stanley; Perner, Richard J; Mikusa, Joe P; Gauvin, Donna M; Segreti, Jason A; Han, Ping; Zhang, Xu-Feng; Niforatos, Wende; Bianchi, Bruce R; Baker, Scott J; Zhong, Chengmin; Simler, Gricelda H; McDonald, Heath A; Schmidt, Robert G; McGaraughty, Steve P; Chu, Katharine L; Faltynek, Connie R; Kort, Michael E; Reilly, Regina M; Kym, Philip R

    2011-05-01

    Despite the increasing interest in TRPA1 channel as a pain target, its role in cold sensation and body temperature regulation is not clear; the efficacy and particularly side effects resulting from channel blockade remain poorly understood. Here we use a potent, selective, and bioavailable antagonist to address these issues. A-967079 potently blocks human (IC(50): 51 nmol/L, electrophysiology, 67 nmol/L, Ca(2+) assay) and rat TRPA1 (IC(50): 101 nmol/L, electrophysiology, 289 nmol/L, Ca(2+) assay). It is >1000-fold selective over other TRP channels, and is >150-fold selective over 75 other ion channels, enzymes, and G-protein-coupled receptors. Oral dosing of A-967079 produces robust drug exposure in rodents, and exhibits analgesic efficacy in allyl isothiocyanate-induced nocifensive response and osteoarthritic pain in rats (ED(50): 23.2 mg/kg, p.o.). A-967079 attenuates cold allodynia produced by nerve injury but does not alter noxious cold sensation in naive animals, suggesting distinct roles of TRPA1 in physiological and pathological states. Unlike TRPV1 antagonists, A-967079 does not alter body temperature. It also does not produce locomotor or cardiovascular side effects. Collectively, these data provide novel insights into TRPA1 function and suggest that the selective TRPA1 blockade may present a viable strategy for alleviating pain without untoward side effects. Copyright © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  6. [Selective alteration of the declarative memory systems in patients treated with a high number of electroconvulsive therapy sessions].

    Science.gov (United States)

    Rami-González, L; Boget-Llucià, T; Bernardo, M; Marcos, T; Cañizares-Alejos, S; Penadés, R; Portella, M J; Castelví, M; Raspall, T; Salamero, M

    The reversible electrochemical effects of electroconvulsive therapy (ECT) on specific areas of the brain enable the neuroanatomical bases of some cognitive functions to be studied. In research carried out on memory systems, a selective alteration of the declarative ones has been observed after treatment with ECT. Little work has been done to explore the differential alteration of the memory subsystems in patients with a high number of ECT sessions. AIM. To study the declarative and non declarative memory system in psychiatric patients submitted to maintenance ECT treatment, with a high number of previous ECT sessions. 20 patients submitted to treatment with ECT (10 diagnosed as having depression and 10 with schizophrenia) and 20 controls, who were paired by age, sex and psychopathological diagnosis. For the evaluation of the declarative memory system, the Wechsler Memory Scale (WMS) logical memory test was used. The Hanoi Tower procedural test was employed to evaluate the non declarative system. Patients treated with ECT performed worse in the WMS logical memory test, but this was only significant in patients diagnosed as suffering from depression. No significant differences were observed in the Hanoi Tower test. A selective alteration of the declarative systems was observed in patients who had been treated with a high number of ECT sessions, while the non declarative memory systems remain unaffected.

  7. Discrimination of uranium alteration zones in selected areas by use of LANDSAT MSS imagery. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kober, C.L.; Procter-Gregg, H.D.

    1977-02-01

    The surface alteration halos of fifty known uranium occurrences in the Western United States have been analyzed to determine spectral signatures in imagery acquired by the LANDSAT Multi-Spectral Scanner. The deposits included veins and metasediments in the northeast of Washington, batholitic districts in the northwest of Idaho, veins and intrusives in a portion of the Colorado Front Range and sedimentary deposits on the Colorado Plateau. Image analysis employed an analog hybrid video processing system composed of a light table, vidicon camera, image analyzer and color output monitor. A complete description of the theory and methodology is provided in the report.

  8. Selection of tRNA charging quality control mechanisms that increase mistranslation of the genetic code

    DEFF Research Database (Denmark)

    Yadavalli, Srujana S; Ibba, Michael

    2013-01-01

    Mistranslation can follow two events during protein synthesis: production of non-cognate amino acid:transfer RNA (tRNA) pairs by aminoacyl-tRNA synthetases (aaRSs) and inaccurate selection of aminoacyl-tRNAs by the ribosome. Many aaRSs actively edit non-cognate amino acids, but editing mechanisms...... are not evolutionarily conserved, and their physiological significance remains unclear. To address the connection between aaRSs and mistranslation, the evolutionary divergence of tyrosine editing by phenylalanyl-tRNA synthetase (PheRS) was used as a model. Certain PheRSs are naturally error prone, most notably...... a Mycoplasma example that displayed a low level of specificity consistent with elevated mistranslation of the proteome. Mycoplasma PheRS was found to lack canonical editing activity, relying instead on discrimination against the non-cognate amino acid by kinetic proofreading. This mechanism of discrimination...

  9. Selective alterations of neurons and circuits related to early memory loss in Alzheimer’s disease

    Science.gov (United States)

    Llorens-Martín, Maria; Blazquez-Llorca, Lidia; Benavides-Piccione, Ruth; Rabano, Alberto; Hernandez, Felix; Avila, Jesus; DeFelipe, Javier

    2014-01-01

    A progressive loss of episodic memory is a well-known clinical symptom that characterizes Alzheimer’s disease (AD). The beginning of this loss of memory has been associated with the very early, pathological accumulation of tau and neuronal degeneration observed in the entorhinal cortex (EC). Tau-related pathology is thought to then spread progressively to the hippocampal formation and other brain areas as the disease progresses. The major cortical afferent source of the hippocampus and dentate gyrus is the EC through the perforant pathway. At least two main circuits participate in the connection between EC and the hippocampus; one originating in layer II and the other in layer III of the EC giving rise to the classical trisynaptic (ECII → dentate gyrus → CA3 → CA1) and monosynaptic (ECIII → CA1) circuits. Thus, the study of the early pathological changes in these circuits is of great interest. In this review, we will discuss mainly the alterations of the granule cell neurons of the dentate gyrus and the atrophy of CA1 pyramidal neurons that occur in AD in relation to the possible differential alterations of these two main circuits. PMID:24904307

  10. Selective alterations of neurons and circuits related to early memory loss in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    María eLlorens-Martín

    2014-05-01

    Full Text Available A progressive loss of episodic memory is a well-known clinical symptom that characterizes Alzheimer’s disease (AD. The beginning of this loss of memory has been associated with the very early, pathological accumulation of tau and neuronal degeneration observed in the entorhinal cortex (EC. Tau-related pathology is thought to then spread progressively to the hippocampal formation and other brain areas as the disease progresses. The major cortical afferent source of the hippocampus and dentate gyrus is the EC through the perforant pathway. At least two main circuits participate in the connection between EC and the hippocampus; one originating in layer II and the other in layer III of the EC giving rise to the classical trisynaptic (ECII→dentate gyrus→CA3→CA1 and monosynaptic (ECIII→CA1 circuits. Thus, the study of the early pathological changes in these circuits is of great interest. In this review, we will discuss mainly the alterations of the granule cell neurons of the dentate gyrus and the atrophy of CA1 pyramidal neurons that occur in AD in relation to the possible differential alterations of these two main circuits.

  11. Neuropeptide Y response to alcohol is altered in nucleus accumbens of mice selectively bred for drinking to intoxication

    Science.gov (United States)

    Barkley-Levenson, Amanda M.; Ryabinin, Andrey E.; Crabbe, John C.

    2016-01-01

    The High Drinking in the Dark (HDID) mice have been selectively bred for drinking to intoxicating blood alcohol levels and represent a genetic model of risk for binge-like drinking. Presently, little is known about the specific genetic factors that promote excessive intake in these mice. Previous studies have identified neuropeptide Y (NPY) as a potential target for modulating alcohol intake. NPY expression differs in some rodent lines that have been selected for high and low alcohol drinking phenotypes, as well as inbred mouse strains that differ in alcohol preference. Alcohol drinking and alcohol withdrawal also produce differential effects on NPY expression in the brain. Here, we assessed brain NPY protein levels in HDID mice of two replicates of selection and control heterogeneous stock (HS) mice at baseline (water drinking) and after binge-like alcohol drinking to determine whether selection is associated with differences in NPY expression and its sensitivity to alcohol. NPY levels did not differ between HDID and HS mice in any brain region in the water-drinking animals. HS mice showed a reduction in NPY levels in the nucleus accumbens (NAc) – especially in the shell – in ethanol-drinking animals vs. water-drinking controls. However, HDID mice showed a blunted NPY response to alcohol in the NAc core and shell compared to HS mice. These findings suggest that the NPY response to alcohol has been altered by selection for drinking to intoxication in a region-specific manner. Thus, the NPY system may represent a potential target for altering binge-like alcohol drinking in these mice. PMID:26779672

  12. Laserspray ionization on a commercial atmospheric pressure-MALDI mass spectrometer ion source: selecting singly or multiply charged ions.

    Science.gov (United States)

    McEwen, Charles N; Larsen, Barbara S; Trimpin, Sarah

    2010-06-15

    Multiply charged ions, similar to those obtained with electrospray ionization, are produced at atmospheric pressure (AP) using standard MALDI conditions of laser fluence and reflective geometry. Further, the charge state can be switched to singly charged ions nearly instantaneously by changing the voltage applied to the MALDI target plate. Under normal AP-MALDI operating conditions in which a voltage is applied to the target plate, primarily singly charged ions are observed, but at or near zero volts, highly charged ions are observed for peptides and proteins. Thus, switching between singly and multiply charged ions requires only manipulation of a single voltage. As in ESI, multiple charging, produced using the AP-MALDI source, allows compounds with molecular weights beyond the mass-to-charge limit of the mass spectrometer to be observed and improves the fragmentation relative to singly charged ions.

  13. Lowering the overall charge on TMPyP4 improves its selectivity for G-quadruplex DNA.

    Science.gov (United States)

    Ruan, Thomas L; Davis, Supriya J; Powell, Barrett M; Harbeck, Cole P; Habdas, Jan; Habdas, Piotr; Yatsunyk, Liliya A

    2017-01-01

    Ligands that stabilize non-canonical DNA structures called G-quadruplexes (GQs) might have applications in medicine as anti-cancer agents, due to the involvement of GQ DNA in a variety of cancer-related biological processes. Five derivatives of 5,10,15,20-tetrakis(N-methyl-4-pyridyl)porphyrin (TMPyP4), where a N-methylpyridyl group was replaced with phenyl (4P3), 4-aminophenyl (PN3M), 4-phenylamidoproline (PL3M), or 4-carboxyphenyl (PC3M and P2C2M) were investigated for their interactions with human telomeric DNA (Tel22) using fluorescence resonance energy transfer (FRET) assay, and UV-visible and circular dichroism spectroscopies in K(+) buffer. The molecules are cationic or zwitterionic with an overall charge of 3+ (4P3, PN3M, and PL3M), 2+ (PC3M) or neutral (P2C2M). All porphyrins except P2C2M stabilize human telomeric DNA in FRET assays by ∼20 °C at 5 eq CD melting experiments suggest that 4P3 is the most stabilizing ligand with a stabilization temperature of 16.8 °C at 4 eq. Importantly, 4P3, PC3M and PL3M demonstrate excellent selectivity for quadruplexes, far superior to that of TMPyP4. Binding constants, determined using UV-vis titrations, correlate with charge: triply cationic 4P3, PN3M and PL3M display Ka of 5-9 μM(-1), doubly cationic PC3M displays Ka of 1 μM(-1), and neutral P2C2M displays weak-to-no binding. UV-vis data suggest that binding interactions are driven by electrostatic attractions and that the binding mode may be base-stacking (or end-stacking) judging by the high values of red shift (15-20 nm) and hypochromicity (40-50%). We conclude that lowering the charge on TMPyP4 to 3+ can achieve the desired balance between stabilizing ability, affinity, and high selectivity required for an excellent quadruplex ligand.

  14. Binding among Select Episodic Elements Is Altered via Active Short-Term Retrieval

    Science.gov (United States)

    Bridge, Donna J.; Voss, Joel L.

    2015-01-01

    Of the many elements that comprise an episode, are any disproportionately bound to the others? We tested whether active short-term retrieval selectively increases binding. Individual objects from multiobject displays were retrieved after brief delays. Memory was later tested for the other objects. Cueing with actively retrieved objects facilitated…

  15. Charge- and Size-Selective Molecular Separation using Ultrathin Cellulose Membranes

    KAUST Repository

    Puspasari, Tiara

    2016-08-30

    To date, it is still a challenge to prepare high-flux and highselectivity microporous membranes thinner than 20 nm without introducing defects. In this work, we report for the first time the application of cellulose membranes for selective separation of small molecules. A freestanding cellulose membrane as thin as 10 nm has been prepared through regeneration of trimethylsilyl cellulose (TMSC). The freestanding membrane can be transferred to any desired substrate and shows a normalized flux as high as 700 L m−2 h−1 bar−1 when supported by a porous alumina disc. According to filtration experiments, the membrane exhibits precise size-sieving performances with an estimated pore size between 1.5–3.5 nm depending on the regeneration period and initial TMSC concentration. A perfect discrimination of anionic molecules over neutral species is demonstrated. Moreover, the membrane demonstrates high reproducibility, high scale-up potential, and excellent stability over two months.

  16. Banned -- Select: "a drug to alter the sex of the foetus".

    Science.gov (United States)

    Unnikrishnan, P V

    1993-04-01

    In 1991, the Government of Gujarat State, India, banned the manufacture and sale of an Ayurvedic drug called Select. This was the first time an Ayurvedic product had ever been banned. The manufacturer claimed that if a pregnant woman took Select for 45 days after her last menstrual period, she would have a male fetus. Further, the manufacturer marketed the drug as a tool which would change the dowry system (i.e., it would reduce the number of girls in the population). Select's high cost did not deter the naive and trusting public in Gujarat and other states. Drug activists and consumer groups called for the ban and noted that the marketing claims were typical of the unethical behavior of the Ayurvedic market. These consumer groups brought the existence of Select to the attention of the government which admittedly cannot adequately monitor and control the drug market. Groups ranging from illegal smugglers to multinational giants use loopholes in the Drugs and Cosmetics Act and Excise Laws to license their drugs as Ayurvedic/Herbal, but most drugs are hazardous. Policy makers, physicians, nongovernmental and consumer groups, the media, and others should join together to rid India of this unethical practice. They should help the government to implement a rational policy for traditional systems of medicine and, once the policy has been developed to select an essential drug list of Ayurvedic drugs needed for national health programs; monitor and minimize misleading advertisements; screen all existing Ayurvedic drugs and drugs of other traditional medicine systems; and require thorough research on the relevance, usefulness, and safety of new patent drugs of other traditional medicine systems; and require thorough research on the relevance, usefulness, and safety of new patent drugs. The government should declare any products with more than 12% alcohol to be liquor.

  17. Distinct genetic alterations occur in ovarian tumor cells selected for combined resistance to carboplatin and docetaxel

    Directory of Open Access Journals (Sweden)

    Armstrong Stephen R

    2012-11-01

    Full Text Available Abstract Background Current protocols for the treatment of ovarian cancer include combination chemotherapy with a platinating agent and a taxane. However, many patients experience relapse of their cancer and the development of drug resistance is not uncommon, making successful second line therapy difficult to achieve. The objective of this study was to develop and characterize a cell line resistant to both carboplatin and docetaxel (dual drug resistant ovarian cell line and to compare this cell line to cells resistant to either carboplatin or docetaxel. Methods The A2780 epithelial endometrioid ovarian cancer cell line was used to select for isogenic carboplatin, docetaxel and dual drug resistant cell lines. A selection method of gradually increasing drug doses was implemented to avoid clonal selection. Resistance was confirmed using a clonogenic assay. Changes in gene expression associated with the development of drug resistance were determined by microarray analysis. Changes in the expression of selected genes were validated by Quantitative Real-Time Polymerase Chain Reaction (QPCR and immunoblotting. Results Three isogenic cell lines were developed and resistance to each drug or the combination of drugs was confirmed. Development of resistance was accompanied by a reduced growth rate. The microarray and QPCR analyses showed that unique changes in gene expression occurred in the dual drug resistant cell line and that genes known to be involved in resistance could be identified in all cell lines. Conclusions Ovarian tumor cells can acquire resistance to both carboplatin and docetaxel when selected in the presence of both agents. Distinct changes in gene expression occur in the dual resistant cell line indicating that dual resistance is not a simple combination of the changes observed in cell lines exhibiting single agent resistance.

  18. Altered mitochondrial respiration in selectively vulnerable brain subregions following transient forebrain ischemia in the rat.

    Science.gov (United States)

    Sims, N R; Pulsinelli, W A

    1987-11-01

    Mitochondrial respiratory function, assessed from the rate of oxygen uptake by homogenates of rat brain subregions, was examined after 30 min of forebrain ischemia and at recirculation periods of up to 48 h. Ischemia-sensitive regions which develop extensive neuronal loss during the recirculation period (dorsal-lateral striatum, CA1 hippocampus) were compared with ischemia-resistant areas (paramedian neocortex, CA3 plus CA4 hippocampus). All areas showed reductions (to 53-69% of control) during ischemia for oxygen uptake rates determined in the presence of ADP or an uncoupling agent, which then recovered within 1 h of cerebral recirculation. In the ischemia-resistant regions, oxygen uptake rates remained similar to control values for at least 48 h of recirculation. After 3 h of recirculation, a significant decrease in respiratory activity (measured in the presence of ADP or uncoupling agent) was observed in the dorsal-lateral striatum which progressed to reductions of greater than 65% of the initial activity by 24 h. In the CA1 hippocampus, oxygen uptake rates were unchanged for 24 h, but were significantly reduced (by 30% in the presence of uncoupling agent) at 48 h. These alterations parallel the development of histological evidence of ischemic cell change determined previously and apparently precede the appearance of differential changes between sensitive and resistant regions in the content of high-energy phosphate compounds. These results suggest that alterations of mitochondrial activity are a relatively early change in the development of ischemic cell death and provide a sensitive biochemical marker for this process.

  19. Selective behavioral alterations on addition of a 4'-phenyl group to cocaine.

    Science.gov (United States)

    Seale, T W; Niekrasz, I; Chang, F; Singh, S; Basmadjian, G P

    1996-01-31

    We synthesized a cocaine analog in which a phenyl group was added at the para-position of the benzene ring of cocaine. This substitution caused a modest reduction (four-fold compared with cocaine) in binding potency for the primate (Papio) dopamine transporter as judged by displacement of [3H]WIN 35,428 binding from caudate/putamen membranes. Behavioral effects of this structural modification in the mouse were complex and selective, comprising absence of stimulation of locomotor activity, enhanced inhibition of locomotion and reduced lethal potency. Convulsant potency was unaltered. Substituents at the 4'-position of cocaine are important in its actions. Simple changes in the chemical structure of this drug may produce complex and selective changes in its neurochemical and behavioral actions.

  20. Gender selection: pressure from patients and industry should not alter our adherence to ethical guidelines.

    Science.gov (United States)

    Sauer, Mark V

    2004-11-01

    Patients who undergo assisted reproduction occasionally request that physicians intervene with techniques that help to determine the gender of their offspring. Conventionally, all of these methods require an invasive procedure that places both the mother and pregnancy at risk. However, for sex-linked disorders, the risk/benefit ratio is favorable; therefore, in such cases, gender selection is warranted. The recent introduction of noninvasive techniques for X- and Y-chromosome-bearing sperm sorting now provides another option for couples. However, the method is not absolute in its ability to sort sperm correctly; in many cases, the offspring are not of the desired sex. Sperm sorting has been marketed increasingly as a means for "family balancing," which is contrary to recommendations that are offered by ethics committees of several professional societies. More studies are needed with respect to the impact of gender selection on families before this method is introduced into routine practice.

  1. Archaerhodopsin Selectively and Reversibly Silences Synaptic Transmission through Altered pH

    Directory of Open Access Journals (Sweden)

    Mohamady El-Gaby

    2016-08-01

    Full Text Available Tools that allow acute and selective silencing of synaptic transmission in vivo would be invaluable for understanding the synaptic basis of specific behaviors. Here, we show that presynaptic expression of the proton pump archaerhodopsin enables robust, selective, and reversible optogenetic synaptic silencing with rapid onset and offset. Two-photon fluorescence imaging revealed that this effect is accompanied by a transient increase in pH restricted to archaerhodopsin-expressing boutons. Crucially, clamping intracellular pH abolished synaptic silencing without affecting the archaerhodopsin-mediated hyperpolarizing current, indicating that changes in pH mediate the synaptic silencing effect. To verify the utility of this technique, we used trial-limited, archaerhodopsin-mediated silencing to uncover a requirement for CA3-CA1 synapses whose afferents originate from the left CA3, but not those from the right CA3, for performance on a long-term memory task. These results highlight optogenetic, pH-mediated silencing of synaptic transmission as a spatiotemporally selective approach to dissecting synaptic function in behaving animals.

  2. Charge-carrier selective electrodes for organic bulk heterojunction solar cell by contact-printed siloxane oligomers

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Hyun-Sik; Khang, Dahl-Young, E-mail: dykhang@yonsei.ac.kr

    2015-08-31

    ‘Smart’ (or selective) electrode for charge carriers, both electrons and holes, in organic bulk-heterojunction (BHJ) solar cells using insertion layers made of hydrophobically-recovered and contact-printed siloxane oligomers between electrodes and active material has been demonstrated. The siloxane oligomer insertion layer has been formed at a given interface simply by conformally-contacting a cured slab of polydimethylsiloxane stamp for less than 100 s. All the devices, either siloxane oligomer printed at one interface only or printed at both interfaces, showed efficiency enhancement when compared to non-printed ones. The possible mechanism that is responsible for the observed efficiency enhancement has been discussed based on the point of optimum symmetry and photocurrent analysis. Besides its simplicity and large-area applicability, the demonstrated contact-printing technique does not involve any vacuum or wet processing steps and thus can be very useful for the roll-based, continuous production scheme for organic BHJ solar cells. - Highlights: • Carrier-selective insertion layer in organic bulk heterojunction solar cells • Simple contact-printing of siloxane oligomers improves cell efficiency. • Printed siloxane layer reduces carrier recombination at electrode surfaces. • Siloxane insertion layer works equally well at both electrode surfaces. • Patterned PDMS stamp shortens the printing time within 100 s.

  3. Molecular interaction of selected phytochemicals under the charged environment of Plasmodium falciparum chloroquine resistance transporter (PfCRT) model.

    Science.gov (United States)

    Patel, Saumya K; Khedkar, Vijay M; Jha, Prakash C; Jasrai, Yogesh T; Pandya, Himanshu A; George, Linz-Buoy; Highland, Hyacinth N; Skelton, Adam A

    2016-01-01

    Phytochemicals of Catharanthus roseus Linn. and Tylophora indica have been known for their inhibition of malarial parasite, Plasmodium falciparum in cell culture. Resistance to chloroquine (CQ), a widely used antimalarial drug, is due to the CQ resistance transporter (CRT) system. The present study deals with computational modeling of Plasmodium falciparum chloroquine resistance transporter (PfCRT) protein and development of charged environment to mimic a condition of resistance. The model of PfCRT was developed using Protein homology/analogy engine (PHYRE ver 0.2) and was validated based on the results obtained using PSI-PRED. Subsequently, molecular interactions of selected phytochemicals extracted from C. roseus Linn. and T. indica were studied using multiple-iterated genetic algorithm-based docking protocol in order to investigate the translocation of these legends across the PfCRT protein. Further, molecular dynamics studies exhibiting interaction energy estimates of these compounds within the active site of the protein showed that compounds are more selective toward PfCRT. Clusters of conformations with the free energy of binding were estimated which clearly demonstrated the potential channel and by this means the translocation across the PfCRT is anticipated.

  4. Medulloblastoma-associated DDX3 variant selectively alters the translational response to stress.

    Science.gov (United States)

    Oh, Sekyung; Flynn, Ryan A; Floor, Stephen N; Purzner, James; Martin, Lance; Do, Brian T; Schubert, Simone; Vaka, Dedeepya; Morrissy, Sorana; Li, Yisu; Kool, Marcel; Hovestadt, Volker; Jones, David T W; Northcott, Paul A; Risch, Thomas; Warnatz, Hans-Jörg; Yaspo, Marie-Laure; Adams, Christopher M; Leib, Ryan D; Breese, Marcus; Marra, Marco A; Malkin, David; Lichter, Peter; Doudna, Jennifer A; Pfister, Stefan M; Taylor, Michael D; Chang, Howard Y; Cho, Yoon-Jae

    2016-05-10

    DDX3X encodes a DEAD-box family RNA helicase (DDX3) commonly mutated in medulloblastoma, a highly aggressive cerebellar tumor affecting both children and adults. Despite being implicated in several facets of RNA metabolism, the nature and scope of DDX3's interactions with RNA remain unclear. Here, we show DDX3 collaborates extensively with the translation initiation machinery through direct binding to 5'UTRs of nearly all coding RNAs, specific sites on the 18S rRNA, and multiple components of the translation initiation complex. Impairment of translation initiation is also evident in primary medulloblastomas harboring mutations in DDX3X, further highlighting DDX3's role in this process. Arsenite-induced stress shifts DDX3 binding from the 5'UTR into the coding region of mRNAs concomitant with a general reduction of translation, and both the shift of DDX3 on mRNA and decreased translation are blunted by expression of a catalytically-impaired, medulloblastoma-associated DDX3R534H variant. Furthermore, despite the global repression of translation induced by arsenite, translation is preserved on select genes involved in chromatin organization in DDX3R534H-expressing cells. Thus, DDX3 interacts extensively with RNA and ribosomal machinery to help remodel the translation landscape in response to stress, while cancer-related DDX3 variants adapt this response to selectively preserve translation.

  5. Acoustic noise alters selective attention processes as indicated by direct current (DC) brain potential changes.

    Science.gov (United States)

    Trimmel, Karin; Schätzer, Julia; Trimmel, Michael

    2014-09-26

    Acoustic environmental noise, even of low to moderate intensity, is known to adversely affect information processing in animals and humans via attention mechanisms. In particular, facilitation and inhibition of information processing are basic functions of selective attention. Such mechanisms can be investigated by analyzing brain potentials under conditions of externally directed attention (intake of environmental information) versus internally directed attention (rejection of environmental stimuli and focusing on memory/planning processes). This study investigated brain direct current (DC) potential shifts-which are discussed to represent different states of cortical activation-of tasks that require intake and rejection of environmental information under noise. It was hypothesized that without background noise rejection tasks would show more positive DC potential changes compared to intake tasks and that under noise both kinds of tasks would show positive DC shifts as an expression of cortical inhibition caused by noise. DC potential shifts during intake and rejection tasks were analyzed at 16 standard locations in 45 persons during irrelevant speech or white noise vs. control condition. Without noise, rejection tasks were associated with more positive DC potential changes compared to intake tasks. During background noise, however, this difference disappeared and both kinds of tasks led to positive DC shifts. Results suggest-besides some limitations-that noise modulates selective attention mechanisms by switching to an environmental information processing and noise rejection mode, which could represent a suggested "attention shift". Implications for fMRI studies as well as for public health in learning and performance environments including susceptible persons are discussed.

  6. Acoustic Noise Alters Selective Attention Processes as Indicated by Direct Current (DC Brain Potential Changes

    Directory of Open Access Journals (Sweden)

    Karin Trimmel

    2014-09-01

    Full Text Available Acoustic environmental noise, even of low to moderate intensity, is known to adversely affect information processing in animals and humans via attention mechanisms. In particular, facilitation and inhibition of information processing are basic functions of selective attention. Such mechanisms can be investigated by analyzing brain potentials under conditions of externally directed attention (intake of environmental information versus internally directed attention (rejection of environmental stimuli and focusing on memory/planning processes. This study investigated brain direct current (DC potential shifts—which are discussed to represent different states of cortical activation—of tasks that require intake and rejection of environmental information under noise. It was hypothesized that without background noise rejection tasks would show more positive DC potential changes compared to intake tasks and that under noise both kinds of tasks would show positive DC shifts as an expression of cortical inhibition caused by noise. DC potential shifts during intake and rejection tasks were analyzed at 16 standard locations in 45 persons during irrelevant speech or white noise vs. control condition. Without noise, rejection tasks were associated with more positive DC potential changes compared to intake tasks. During background noise, however, this difference disappeared and both kinds of tasks led to positive DC shifts. Results suggest—besides some limitations—that noise modulates selective attention mechanisms by switching to an environmental information processing and noise rejection mode, which could represent a suggested “attention shift”. Implications for fMRI studies as well as for public health in learning and performance environments including susceptible persons are discussed.

  7. A new approach for hydrothermal alteration mapping by selecting and interpreting principal components in Landsat ETM+ images

    Directory of Open Access Journals (Sweden)

    Mohammad Kashkoei Jahroomi

    2016-07-01

    Full Text Available Introduction In remote sensing studies, especially those in which multi-spectral image data are used, (i.e., Landsat-7 Enhanced Thematic Mapper, various statistical methods are often applied for image enhancement and feature extraction (Reddy, 2008. Principal component analysis is a multivariate statistical technique which is frequently used in multidimensional data analysis. This method attempts to extract and place the spectral information into a smaller set of new components that are more interpretable. However, the results obtained from this method are not so straightforward and require somewhat sophisticated techniques to interpret (Drury, 2001. In this paper we present a new approach for mapping of hydrothermal alteration by analyzing and selecting the principal components extracted through processing of Landsat ETM+ images. The study area is located in a mountainous region of southern Kerman. Geologically, it lies in the volcanic belt of central Iran adjacent to the Gogher-Baft ophiolite zone. The region is highly altered with sericitic, propyliticand argillic alterationwell developed, and argillic alteration is limited (Jafari, 2009; Masumi and Ranjbar, 2011. Multispectral data of Landsat ETM+ was acquired (path 181, row 34 in this study. In these images the color composites of Band 7, Band 4 and Band 1 in RGB indicate the lithology outcropping in the study area. The principal component analysis (PCA ofimage data is often implemented computationally using three steps: (1 Calculation of the variance, covariance matrix or correlation matrix of the satellite sensor data. (2 Computation of the eigenvalues and eigenvectors of the variance-covariance matrix or correlation matrix, and (3 Linear transformation of the image data using the coefficients of the eigenvector matrix. Results By applying PCA to the spectral data, according to the eigenvectors obtained, 6 principal components were extracted from the data set. In the PCA matrix, theeigen

  8. Sugar overconsumption during adolescence selectively alters motivation and reward function in adult rats.

    Directory of Open Access Journals (Sweden)

    Leandro F Vendruscolo

    Full Text Available BACKGROUND: There has been a dramatic escalation in sugar intake in the last few decades, most strikingly observed in the adolescent population. Sugar overconsumption has been associated with several adverse health consequences, including obesity and diabetes. Very little is known, however, about the impact of sugar overconsumption on mental health in general, and on reward-related behavioral disorders in particular. This study examined in rats the effects of unlimited access to sucrose during adolescence on the motivation for natural and pharmacological rewards in adulthood. METHODOLOGY/PRINCIPAL FINDINGS: Adolescent rats had free access to 5% sucrose or water from postnatal day 30 to 46. The control group had access to water only. In adulthood, rats were tested for self-administration of saccharin (sweet, maltodextrin (non-sweet, and cocaine (a potent drug of abuse using fixed- and progressive-ratio schedules, and a concentration-response curve for each substance. Adult rats, exposed or not exposed to sucrose, were tested for saccharin self-administration later in life to verify the specificity of adolescence for the sugar effects. Sugar overconsumption during adolescence, but not during adulthood, reduced the subsequent motivation for saccharin and maltodextrin, but not cocaine. This selective decrease in motivation is more likely due to changes in brain reward processing than changes in gustatory perception. CONCLUSIONS/SIGNIFICANCE: Sugar overconsumption induces a developmental stage-specific chronic depression in reward processing that may contribute to an increase in the vulnerability to reward-related psychiatric disorders.

  9. A highly potent and selective Vps34 inhibitor alters vesicle trafficking and autophagy.

    Science.gov (United States)

    Ronan, Baptiste; Flamand, Odile; Vescovi, Lionel; Dureuil, Christine; Durand, Laurence; Fassy, Florence; Bachelot, Marie-France; Lamberton, Annabelle; Mathieu, Magali; Bertrand, Thomas; Marquette, Jean-Pierre; El-Ahmad, Youssef; Filoche-Romme, Bruno; Schio, Laurent; Garcia-Echeverria, Carlos; Goulaouic, Hélène; Pasquier, Benoit

    2014-12-01

    Vps34 is a phosphoinositide 3-kinase (PI3K) class III isoform that has attracted major attention over the recent years because of its role in autophagy. Herein we describe the biological characterization of SAR405, which is a low-molecular-mass kinase inhibitor of Vps34 (KD 1.5 nM). This compound has an exquisite protein and lipid kinase selectivity profile that is explained by its unique binding mode and molecular interactions within the ATP binding cleft of human Vps34. To the best of our knowledge, this is the first potent and specific Vps34 inhibitor described so far. Our results demonstrate that inhibition of Vps34 kinase activity by SAR405 affects both late endosome-lysosome compartments and prevents autophagy. Moreover, we show that the concomitant inhibition of Vps34 and mTOR, with SAR405 and the US Food and Drug Administration-approved mTOR inhibitor everolimus, results in synergistic antiproliferative activity in renal tumor cell lines, indicating a potential clinical application in cancer.

  10. Altering small and medium alcohol selectivity in the wax ester synthase.

    Science.gov (United States)

    Barney, Brett M; Ohlert, Janet M; Timler, Jacobe G; Lijewski, Amelia M

    2015-11-01

    The bifunctional wax ester synthase/acyl-coenzyme A:diacylglycerol acyltransferase (WS/DGAT or wax ester synthase) catalyzes the terminal reaction in the bacterial wax ester biosynthetic pathway, utilizing a range of alcohols and fatty acyl-CoAs to synthesize the corresponding wax ester. The wild-type wax ester synthase Maqu_0168 from Marinobacter aquaeolei VT8 exhibits a preference for longer fatty alcohols, while applications with smaller alcohols would yield products with desired biotechnological properties. Small and medium chain length alcohol substrates are much poorer substrates for the native enzyme, which may hinder broad application of the wax ester synthase in many proposed biosynthetic schemes. Developing approaches to improve enzyme activity toward specific smaller alcohol substrates first requires a clear understanding of which amino acids of the primary sequences of these enzymes contribute to substrate specificity in the native enzyme. In this report, we surveyed a range of potential residues and identified the leucine at position 356 and methionine at position 405 in Maqu_0168 as residues that affected selectivity toward small, branched, and aromatic alcohols when substituted with different amino acids. This analysis provides evidence of residues that line the binding site for wax ester synthase, which will aid rational approaches to improve this enzyme with specific substrates.

  11. Trap-Assisted Transport and Non-Uniform Charge Distribution in Sulfur-Rich PbS Colloidal Quantum Dot-based Solar Cells with Selective Contacts.

    Science.gov (United States)

    Malgras, Victor; Zhang, Guanran; Nattestad, Andrew; Clarke, Tracey M; Mozer, Attila J; Yamauchi, Yusuke; Kim, Jung Ho

    2015-12-09

    This study reports evidence of dispersive transport in planar PbS colloidal quantum dot heterojunction-based devices as well as the effect of incorporating a MoO3 hole selective layer on the charge extraction behavior. Steady state and transient characterization techniques are employed to determine the complex recombination processes involved in such devices. The addition of a selective contact drastically improves the device efficiency up to 3.15% (especially due to increased photocurrent and decreased series resistance) and extends the overall charge lifetime by suppressing the main first-order recombination pathway observed in device without MoO3. The lifetime and mobility calculated for our sulfur-rich PbS-based devices are similar to previously reported values in lead-rich quantum dots-based solar cells. Nevertheless, strong Shockley-Read-Hall mechanisms appear to keep restricting charge transport, as the equilibrium voltage takes more than 1 ms to be established.

  12. Selective gas adsorption in a pair of robust isostructural MOFs differing in framework charge and anion loading.

    Science.gov (United States)

    Cowan, Matthew G; Miller, Reece G; Southon, Peter D; Price, Jason R; Yazaydin, Ozgur; Lane, Joseph R; Kepert, Cameron J; Brooker, Sally

    2014-11-17

    Activation of the secondary assembly instructions in the mononuclear pyrazine imide complexes [Co(III)(dpzca)2](BF4) or [Co(II)(dpzca)2] and [Ni(II)(dpzca)2] has facilitated the construction of two robust nanoporous three-dimensional coordination polymers, [Co(III)(dpzca)2Ag](BF4)2·2(H2O) [1·2(H2O)] and [Ni(II)(dpzca)2Ag]BF4·0.5(acetone) [2·0.5(acetone)]. Despite the difference in charge distribution and anion loading, the framework structures of 1·2(H2O) and 2·0.5(acetone) are isostructural. One dimensional channels along the b-axis permeate the structures and contain the tetrafluoroborate counterions (the Co(III)-based MOF has twice as many BF4(-) anions as the Ni(II)-based MOF) and guest solvent molecules. These anions are not readily exchanged whereas the solvent molecules can be reversibly removed and replaced. The H2, N2, CO2, CH4, H2O, CH3OH, and CH3CN sorption behaviors of the evacuated frameworks 1 and 2 at 298 K have been studied, and modeled, and both show very high selectivity for CO2 over N2. The increased anion loading in the channels of Co(III)-based MOF 1 relative to Ni(II)-based MOF 2 results in increased selectivity for CO2 over N2 but a decrease in the sorption kinetics and storage capacity of the framework.

  13. Selective alteration of sodium channel gating by Australian funnel-web spider toxins.

    Science.gov (United States)

    Nicholson, G M; Little, M J; Tyler, M; Narahashi, T

    1996-01-01

    The actions of potent mammalian neurotoxins isolated from the venom of two Australian funnel-web spiders were investigated using both electrophysiological and neurochemical techniques. Whole-cell patch clamp recording of sodium currents in rat dorsal root ganglion neurons revealed that versutoxin (VTX), isolated from the venom of Hadronyche versuta, produced a concentration-dependent slowing or removal of tetrodotoxin-sensitive (TTX-S) sodium current inactivation and a reduction in peak TTX-S sodium current. In contrast, VTX had no effect on tetrodotoxin-resistant (TTX-R) sodium currents or potassium currents. VTX also shifted the voltage dependence of sodium channel activation in the hyperpolarizing direction and increased the rate of recovery from inactivation. Ion flux studies performed in rat brain synaptosomes also revealed that robustoxin (RTX), from the venom of Atrax robustus, and VTX both produced a partial activation of 22Na+ flux and an inhibition of batrachotoxin-activated 22Na+ flux. This inhibition of flux through batrachotoxin-activated channels was not due to an interaction with neurotoxin receptor site 1 since [3H]saxitoxin binding was unaffected. In addition, the partial activation of 22Na+ flux was not enhanced in the presence of alpha-scorpion toxin and further experiments suggest that VTX also enhances [3H]batrachotoxin binding. These selective actions of funnel-web spider toxins on sodium channel function are comparable to those of alpha-scorpion and sea anemone toxins which bind to neurotoxin receptor site 3 on the channel to slow channel inactivation profoundly. Also, these modifications of sodium channel gating and kinetics are consistent with actions of the spider toxins to produce repetitive firing of action potentials.

  14. Simulation of Pore Width and Pore Charge Effects on Selectivities of CO2 vs. H2 from a Syngas-like Mixture in Carbon Mesopores

    NARCIS (Netherlands)

    Trinh, T.T.; Vlugt, T.J.H.; Hägg, M.B.; Bedeaux, D.; Kjelstrup, S.

    2014-01-01

    Classical molecular dynamics simulations were performed to study the effect of pore width and surface charge in carbon mesoporous materials on adsorption and diffusion selectivities of CO2/H2 in a syngas-like mixture (mole fraction of CO2 = 0.30). The pore width of the graphite slit varied from 2.5

  15. Selective effects of charge on G protein activation by FSH-receptor residues 551-555 and 650-653.

    Science.gov (United States)

    Grasso, P; Deziel, M R; Reichert, L E

    1995-01-01

    Two cytosolic regions of the rat testicular FSH receptor (FSHR), residues 533-555 and 645-653, have been identified as G protein-coupling domains. We localized the activity in these domains to their C-terminal sequences, residues 551-555 (KIAKR, net charge +3) and 650-653 (RKSH, net charge +3), and examined the effects of charge on G protein activation by the C-terminal peptides, using synthetic analogs containing additions, through alanine (A) linkages, of arginine (R, +), histidine (H, +) or both. RA-KIAKR (net charge +4) mimicked the effect of FSHR-(551-555) on guanine nucleotide exchange in rat testis membranes, but reduced its ability to inhibit FSH-stimulated estradiol biosynthesis in cultured rat Sertoli cells. Further increasing net charge by the addition of H (HARA-KIAKR, net charge +5) increased guanosine 5'-triphosphate (GTP) binding, but eliminated FSHR-(551-555) effects on FSH-stimulated steroidogenesis. HA-RKSH (net charge +4) significantly inhibited guanine nucleotide exchange in rat testis membranes, but stimulated basal and potentiated FSH-induced estradiol biosynthesis in cultured rat Sertoli cells. Addition of two H residues (HAHA-RKSH, net charge +5) restored GTP binding and further potentiated basal and FSH-stimulated steroidogenesis. These results suggest that positive charges in G protein-coupling domains of the FSHR play a role in modulating G protein activation and postbinding effects of FSH, such as steroidogenesis.

  16. An alpha-helical cationic antimicrobial peptide selectively modulates macrophage responses to lipopolysaccharide and directly alters macrophage gene expression.

    Science.gov (United States)

    Scott, M G; Rosenberger, C M; Gold, M R; Finlay, B B; Hancock, R E

    2000-09-15

    Certain cationic antimicrobial peptides block the binding of LPS to LPS-binding protein and reduce the ability of LPS to induce the production of inflammatory mediators by macrophages. To gain a more complete understanding of how LPS activates macrophages and how cationic peptides influence this process, we have used gene array technology to profile gene expression patterns in macrophages treated with LPS in the presence or the absence of the insect-derived cationic antimicrobial peptide CEMA (cecropin-melittin hybrid). We found that CEMA selectively blocked LPS-induced gene expression in the RAW 264.7 macrophage cell line. The ability of LPS to induce the expression of >40 genes was strongly inhibited by CEMA, while LPS-induced expression of another 16 genes was relatively unaffected. In addition, CEMA itself induced the expression of a distinct set of 35 genes, including genes involved in cell adhesion and apoptosis. Thus, CEMA, a synthetic alpha-helical peptide, selectively modulates the transcriptional response of macrophages to LPS and can alter gene expression in macrophages.

  17. Breeding biology and nest-site selection of red-tailed hawks in an altered desert grassland

    Science.gov (United States)

    Hobbs, R.J.; DeStefano, S.; Halvorson, W.L.

    2006-01-01

    Red-tailed Hawks (Buteo jamaicensis) have expanded their range as trees have invaded formerly-open grasslands. Desert grasslands of southern Arizona have been invaded by mesquite trees (Prosopis velutina) since Anglo-American settlement and now support a large population of Red-tailed Hawks. We studied a population of Red-tailed Hawks in an altered desert grassland in southern Arizona. Our objectives were to determine what environmental characteristics influence Red-tailed Hawk habitat selection in mesquite-invaded desert grasslands and to evaluate the habitat quality of these grasslands for Red-tailed Hawks based on nesting density, nest success, and productivity. Red-tailed Hawks had 86% (95% C.I. = 73-99) nest success and 1.82 young per breeding pair (95% C.I. = 1.41-2.23). Nesting density was 0.15 (95% CI = 0.08-0.21) breeding pairs/km2 and the mean nearest-neighbor distance was 1.95 km (95% C.I. = 1.74-2.16). Red-tailed Hawks selected nest-sites with taller nest-trees and greater tree height and cover than were available at random. Mesquite trees in desert grasslands provide abundant potential nesting structures for Red-tailed Hawks. ?? 2006 The Raptor Research Foundation, Inc.

  18. Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution.

    Science.gov (United States)

    Guillén, Yolanda; Ruiz, Alfredo

    2012-02-01

    Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution.

  19. Gene alterations at Drosophila inversion breakpoints provide prima facie evidence for natural selection as an explanation for rapid chromosomal evolution

    Directory of Open Access Journals (Sweden)

    Guillén Yolanda

    2012-02-01

    Full Text Available Abstract Background Chromosomal inversions have been pervasive during the evolution of the genus Drosophila, but there is significant variation between lineages in the rate of rearrangement fixation. D. mojavensis, an ecological specialist adapted to a cactophilic niche under extreme desert conditions, is a chromosomally derived species with ten fixed inversions, five of them not present in any other species. Results In order to explore the causes of the rapid chromosomal evolution in D. mojavensis, we identified and characterized all breakpoints of seven inversions fixed in chromosome 2, the most dynamic one. One of the inversions presents unequivocal evidence for its generation by ectopic recombination between transposon copies and another two harbor inverted duplications of non-repetitive DNA at the two breakpoints and were likely generated by staggered single-strand breaks and repair by non-homologous end joining. Four out of 14 breakpoints lay in the intergenic region between preexisting duplicated genes, suggesting an adaptive advantage of separating previously tightly linked duplicates. Four out of 14 breakpoints are associated with transposed genes, suggesting these breakpoints are fragile regions. Finally two inversions contain novel genes at their breakpoints and another three show alterations of genes at breakpoints with potential adaptive significance. Conclusions D. mojavensis chromosomal inversions were generated by multiple mechanisms, an observation that does not provide support for increased mutation rate as explanation for rapid chromosomal evolution. On the other hand, we have found a number of gene alterations at the breakpoints with putative adaptive consequences that directly point to natural selection as the cause of D. mojavensis rapid chromosomal evolution.

  20. High-Fat Diet-Induced Alterations in the Feeding Suppression of Low-Dose Nisoxetine, a Selective Norepinephrine Reuptake Inhibitor

    OpenAIRE

    Bello, Nicholas T.; Walters, Amy L.; Verpeut, Jessica L.; Priscila P. Cunha

    2013-01-01

    Central noradrenergic pathways are involved in feeding and cardiovascular control, physiological processes altered by obesity. The present studies determined how high-fat feeding and body weight gain alter the sensitivity to the feeding suppression and neural activation to a selective norepinephrine reuptake inhibitor, nisoxetine. Acute administration of nisoxetine (saline: 0, 3, 10, and 30 mg/kg; IP) resulted in a dose-dependent reduction in the 24 h refeeding response in male Sprague Dawley...

  1. Matrix-assisted laser desorption/ionization mass spectrometry method for selectively producing either singly or multiply charged molecular ions.

    Science.gov (United States)

    Trimpin, Sarah; Inutan, Ellen D; Herath, Thushani N; McEwen, Charles N

    2010-01-01

    Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is noted for its ability to produce primarily singly charged ions. This is an attribute when using direct ionization for complex mixtures such as protein digests or synthetic polymers. However, the ability to produce multiply charged ions, as with electrospray ionization (ESI), has advantages such as extending the mass range on mass spectrometers with limited mass-to-charge (m/z) range and enhancing fragmentation for structural characterization. We designed and fabricated a novel field free transmission geometry atmopsheric pressure (AP) MALDI source mounted to a high-mass resolution Orbitrap Exactive mass spectrometer. We report the ability to produce at will either singly charged ions or highly charged ions using a MALDI process by simply changing the matrix or the matrix preparation conditions. Mass spectra with multiply charged ions very similar to those obtained with ESI of proteins such as cytochrome c and ubiquitin are obtained with low femtomole amounts applied to the MALDI target plate and for peptides such as angiotensin I and II with application of attomole amounts. Single scan acquisitions produce sufficient ion current even from proteins.

  2. Study on the Site Selection Optimization of Electric Vehicle Charging Station%电动汽车充电站选址优化研究

    Institute of Scientific and Technical Information of China (English)

    杨现青; 刘法胜; 杨玲玲

    2016-01-01

    Electric vehicle charging station is an important factor affecting the development of electric vehicles ,the promotion of electric vehicles is of great significance .At present ,the construction of the supporting facilities of the charging station lags behind the development of the electric vehicle ,w hich has already hindered the development of the electric vehicle .And for the charging station construction site is reasonable to affect the charging station operating efficiency ,quality of service and security .Firstly ,this paper analyzed the current situation of the research on the location and layout of the charging station of the electric vehicle ,and summarized the factors that affect the location and layout of the charging station and the principle of the location and layout of the charging station . On the basis of meeting the location principle ,a nonlinear objective function was established ,which was based on the charge demand point distribution ,and establishes the maximum service radius of the charging station and the maximum service quantity of the charging station .In order to solve the objective function ,genetic algorithm was used to optimize the objective function .At last ,the location of the charging station and the range of the charging demand point were calculated by the simulation .Simulation results show that the proposed model can achieve a better site selection ,in reality ,it can provide some reference for the site selection of the charging station .%电动汽车充电站是影响电动汽车发展的一个重要因素,对电动车的推广具有重要意义。当前充电站配套设施建设的滞后阻碍电动汽车的发展。充电站建设前期选址是否合理影响着充电站的运营效益、服务质量以及安全性。针对当前电动汽车充电站选址布局的研究现状,总结影响充电站选址布局的因素和充电站选址布局原则。在满足选址原则的基础上,考虑充电需

  3. Inactivation of a single copy of Crebbp selectively alters pre-mRNA processing in mouse hematopoietic stem cells.

    Directory of Open Access Journals (Sweden)

    Madeleine E Lemieux

    Full Text Available Global expression analysis of fetal liver hematopoietic stem cells (FL HSCs revealed the presence of unspliced pre-mRNA for a number of genes in normal FL HSCs. In a subset of these genes, Crebbp+/- FL HSCs had less unprocessed pre-mRNA without a corresponding reduction in total mRNA levels. Among the genes thus identified were the key regulators of HSC function Itga4, Msi2 and Tcf4. A similar but much weaker effect was apparent in Ep300+/- FL HSCs, indicating that, in this context as in others, the two paralogs are not interchangeable. As a group, the down-regulated intronic probe sets could discriminate adult HSCs from more mature cell types, suggesting that the underlying mechanism is regulated with differentiation stage and is active in both fetal and adult hematopoiesis. Consistent with increased myelopoiesis in Crebbp hemizygous mice, targeted reduction of CREBBP abundance by shRNA in the multipotent EML cell line triggered spontaneous myeloid differentiation in the absence of the normally required inductive signals. In addition, differences in protein levels between phenotypically distinct EML subpopulations were better predicted by taking into account not only the total mRNA signal but also the amount of unspliced message present. CREBBP thus appears to selectively influence the timing and degree of pre-mRNA processing of genes essential for HSC regulation and thereby has the potential to alter subsequent cell fate decisions in HSCs.

  4. Extensive evolutionary changes in regulatory element activity during human origins are associated with altered gene expression and positive selection.

    Directory of Open Access Journals (Sweden)

    Yoichiro Shibata

    2012-06-01

    Full Text Available Understanding the molecular basis for phenotypic differences between humans and other primates remains an outstanding challenge. Mutations in non-coding regulatory DNA that alter gene expression have been hypothesized as a key driver of these phenotypic differences. This has been supported by differential gene expression analyses in general, but not by the identification of specific regulatory elements responsible for changes in transcription and phenotype. To identify the genetic source of regulatory differences, we mapped DNaseI hypersensitive (DHS sites, which mark all types of active gene regulatory elements, genome-wide in the same cell type isolated from human, chimpanzee, and macaque. Most DHS sites were conserved among all three species, as expected based on their central role in regulating transcription. However, we found evidence that several hundred DHS sites were gained or lost on the lineages leading to modern human and chimpanzee. Species-specific DHS site gains are enriched near differentially expressed genes, are positively correlated with increased transcription, show evidence of branch-specific positive selection, and overlap with active chromatin marks. Species-specific sequence differences in transcription factor motifs found within these DHS sites are linked with species-specific changes in chromatin accessibility. Together, these indicate that the regulatory elements identified here are genetic contributors to transcriptional and phenotypic differences among primate species.

  5. Simulations of Adsorption of CO2 and CH4 in MOFs: Effect of the Size and Charge Distribution on the Selectivity

    Science.gov (United States)

    Maiga, Sidi M.; Medina, Mayra A.; Durodola, Oluwaseyitan J.; Gatica, Silvina M.

    2013-08-01

    Using the method of Grand Canonical Monte Carlo we have computed the adsorption of CO2 and CH4 in MOFs with a periodic cubic structure. We used a model of the MOF that allows systematic variations in the charge distribution, size and LJ parameters. We estimated the selectivity of CO2 over CH4 for different temperatures in MOFs with various sizes and charge distributions. The results show that inserting dipoles at the corners of the MOF's unit cell would increase the selectivity of CO2; on the other hand adding quadrupoles to the structure is ineffective. The size of the cell strongly affects the adsorption of CO2 and selectivity: compressing the cell in only 10 % significantly increases the selectivity; expanding the cell by 20 % reduces it. Regarding thermal effects, we estimated that the selectivity drops from 250 to 2 when the temperature rises from 120 K to 300 K. Although this model is inspired by the IRMOF-1, which has a cubic unit cell, it can be adapted to represent other MOFs with noncubic structures by modifying the geometry accordingly. This work implies that MOFs suit gas separation.

  6. Effect of field-focusing and ion selectivity on the extended space charge developed at the microchannel-nanochannel interface.

    Science.gov (United States)

    Liel, Uri; Leibowitz, Neta; Schiffbauer, Jarrod; Park, Sinwook; Yossifon, Gilad

    2016-08-17

    We present results demonstrating the effect of varying microchannel depth and bulk conductivity on the space charge-mediated transition between classical, diffusion-limited current and over-limiting current in microchannel-nanochannel devices. The extended space charge layer develops at the depleted microchannel-nanochannel entrance when the limiting current is exceeded and is correlated with a distinctive maximum in the dc resistance. This maximum is shown to be affected by the microchannel depth, via field-focusing, and solution conductivity. In particular, we observe that upon their increase, the maximum becomes flatter and shifts to higher voltages.

  7. Selective depletion of Mac-1-expressing microglia in rat subventricular zone does not alter neurogenic response early after stroke.

    Science.gov (United States)

    Heldmann, Ursula; Mine, Yutaka; Kokaia, Zaal; Ekdahl, Christine T; Lindvall, Olle

    2011-06-01

    Ischemic stroke induces migration of newly formed neuroblasts, generated by neural stem cells in the adult rat subventricular zone (SVZ), towards the injured striatum where they differentiate into mature neurons. Stroke also leads to accumulation of microglia in the SVZ but their role for neurogenesis is unclear. Here we developed a method for selective depletion of the macrophage antigen complex-1 (Mac-1)-expressing microglia population in the SVZ by intraventricular injection of the immunotoxin Mac-1-saporin in rats. We found that the vast majority of Mac-1+ cells were Iba-1+ microglia. The Mac-1+ population was heterogeneous and included both a small proliferative pool of cells, which was not affected by middle cerebral artery occlusion (MCAO), and a larger subpopulation that changed morphologically into a semi-activated state in response to the insult. This subpopulation did not increase its expression of the phagocytic marker ED1 but exhibited high levels of triggering receptor expressed on myeloid cells-2 (TREM-2), associated with alternative microglia activation. A minor portion of the SVZ Mac-1+ cells originated from the blood early after stroke, but this macrophage population became much more substantial at later stages. Almost 80% reduction of Mac-1-expressing microglia, caused by Mac-1 saporin delivered just before and at 1 week after MCAO, did not alter the numbers of newly formed neuroblasts in the striatum or their migratory distance. These findings indicate that the Mac-1-expressing microglia in the SVZ do not play a major role either for the number of neuroblasts which exit the SVZ or their migration in the striatum early following stroke.

  8. Alteration of Selected Neurotrophic Factors and their Receptor Expression in Mouse Brain Response to Whole-Brain Irradiation.

    Science.gov (United States)

    Pius-Sadowska, Ewa; Kawa, Miłosz Piotr; Kłos, Patrycja; Rogińska, Dorota; Rudnicki, Michał; Boehlke, Marek; Waloszczyk, Piotr; Machaliński, Bogusław

    2016-11-01

    Ionizing radiation can significantly affect brain function in children and young adults, particularly in the hippocampus where neurogenic niches are located. Injury to normal tissue is a major concern when whole-brain irradiation (WBI) is used to treat central nervous system (CNS) tumors, and the pathogenesis of this injury remains poorly understood. We assessed the expression of selected neurotrophins (NTs) and NT receptors (NTRs) in brains of young mice after a single 10 Gy gamma-ray exposure using morphological and molecular analyses [qRT-PCR, Western blot, immunohistochemistry (IHC)] to evaluate WBI-induced injury in its acute phase. Activity of the NT-NTR axes was examined by analysis of ERK and Akt phosphorylation. Using Nissl staining of hippocampus slices to visualize morphological changes, and TUNEL assay and active caspase-3 detection to assess apoptotic cell death, we found evidence of apoptosis and degenerative changes in hippocampal tissue after WBI. Shortly after WBI, we also observed significant overexpression of several NTs (BDNF, NT-3, NGF and GDNF) and NTRs (TrkA, TrkB, TrkC, GFRα-1, and p75NTR) compared to control animals. The upregulated NT and NTR proteins, in part, originated from two analyzed neurogenic areas: the subgranular zone of the hippocampal dentate gyrus and the subventricular zone, as confirmed by IHC. Finally, components of intracellular signaling pathways, including Akt and MAPK, were activated in acute phase after WBI. Given the role of NTs in diverse biological mechanisms, including maintenance and growth of neurons in the adult brain, our findings of altered expression of neurotrophins and their receptors in brain tissue shortly after irradiation suggest that these molecules play a vital role in the pathophysiology of the acute phase of WBI-induced injury.

  9. Testosterone manipulation postcastration does not alter cloacal gland growth differences in male quail selected for divergent plasma corticosterone stress response.

    Science.gov (United States)

    Busso, J M; Satterlee, D G; Roberts, M L; Buchanan, K L; Evans, M R; Marin, R H

    2010-12-01

    Japanese quail selected for reduced (low-stress, LS) rather than exaggerated (high-stress, HS) plasma corticosterone response to brief restraint have consistently shown greater cloacal gland (CG) development, an androgen-dependent trait. In this study, the effects of testosterone implants on levels of plasma testosterone and CG development in castrated LS and HS quail were determined. Stress-line males were castrated and randomly allocated to 1 of 3 testosterone treatments: the empty testosterone (ET), low testosterone (LT), or high testosterone (HT) implant group. Cloacal gland volume was determined at 4 weekly intervals that represented ranges of 1 to 9 d, 8 to 17 d, 15 to 24 d, and 22 to 31 d after castration and testosterone implantation. Levels of plasma testosterone were also assessed at the end of the study. Development of the CG was affected by quail line (LS > HS), testosterone treatment (HT > LT > ET), and time of measurement (1 to 9 d quail, but not in ET-treated quail). However, even though HT implant treatments induced higher CG development than did LT treatments beyond the first interval of CG volume measurement, and despite the finding of greater CG volumes in LS than HS quail during the last 2 measurement intervals within each of the LT and HT groups, no interaction was observed between testosterone implant dosages and quail stress line on CG volume. Thus, by the end of the study, regardless of testosterone dose, CG volume was consistently greater in LS quail than in their HS counterparts. In addition, although, as expected, the testosterone implant treatment significantly altered levels of plasma testosterone (HT > LT > ET), neither quail line nor its interaction with testosterone treatment affected plasma testosterone. The present findings suggest that the often-observed depressed CG development in the HS line may be independent of testosterone effects.

  10. A demographic transition altered the strength of selection for fitness and age-specific survival and fertility in a 19th century American population.

    Science.gov (United States)

    Moorad, Jacob A

    2013-06-01

    Modernization has increased longevity and decreased fertility in many human populations, but it is not well understood how or to what extent these demographic transitions have altered patterns of natural selection. I integrate individual-based multivariate phenotypic selection approaches with evolutionary demographic methods to demonstrate how a demographic transition in 19th century female populations of Utah altered relationships between fitness and age-specific survival and fertility. Coincident with this demographic transition, natural selection for fitness, as measured by the opportunity for selection, increased by 13% to 20% over 65 years. Proportional contributions of age-specific survival to total selection (the complement to age-specific fertility) diminished from approximately one third to one seventh following a marked increase in infant survival. Despite dramatic reductions in age-specific fertility variance at all ages, the absolute magnitude of selection for fitness explained by age-specific fertility increased by approximately 45%. I show that increases in the adaptive potential of fertility traits followed directly from decreased population growth rates. These results suggest that this demographic transition has increased the adaptive potential of the Utah population, intensified selection for reproductive traits, and de-emphasized selection for survival-related traits. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  11. CrossRef Large numbers of cold positronium atoms created in laser-selected Rydberg states using resonant charge exchange

    CERN Document Server

    McConnell, R; Kolthammer, WS; Richerme, P; Müllers, A; Walz, J; Grzonka, D; Zielinski, M; Fitzakerley, D; George, MC; Hessels, EA; Storry, CH; Weel, M

    2016-01-01

    Lasers are used to control the production of highly excited positronium atoms (Ps*). The laser light excites Cs atoms to Rydberg states that have a large cross section for resonant charge-exchange collisions with cold trapped positrons. For each trial with 30 million trapped positrons, more than 700 000 of the created Ps* have trajectories near the axis of the apparatus, and are detected using Stark ionization. This number of Ps* is 500 times higher than realized in an earlier proof-of-principle demonstration (2004 Phys. Lett. B 597 257). A second charge exchange of these near-axis Ps* with trapped antiprotons could be used to produce cold antihydrogen, and this antihydrogen production is expected to be increased by a similar factor.

  12. Neutralizing positive charges at the surface of a protein lowers its rate of amide hydrogen exchange without altering its structure or increasing its thermostability.

    Science.gov (United States)

    Shaw, Bryan F; Arthanari, Haribabu; Narovlyansky, Max; Durazo, Armando; Frueh, Dominique P; Pollastri, Michael P; Lee, Andrew; Bilgicer, Basar; Gygi, Steven P; Wagner, Gerhard; Whitesides, George M

    2010-12-15

    This paper combines two techniques--mass spectrometry and protein charge ladders--to examine the relationship between the surface charge and hydrophobicity of a representative globular protein (bovine carbonic anhydrase II; BCA II) and its rate of amide hydrogen-deuterium (H/D) exchange. Mass spectrometric analysis indicated that the sequential acetylation of surface lysine-ε-NH3(+) groups--a type of modification that increases the net negative charge and hydrophobicity of the surface of BCA II without affecting its secondary or tertiary structure--resulted in a linear decrease in the aggregate rate of amide H/D exchange at pD 7.4, 15 °C. According to analysis with MS, the acetylation of each additional lysine generated between 1.4 and 0.9 additional hydrogens that are protected from H/D exchange during the 2 h exchange experiment at 15 °C, pD 7.4. NMR spectroscopy demonstrated that none of the hydrogen atoms which became protected upon acetylation were located on the side chain of the acetylated lysine residues (i.e., lys-ε-NHCOCH3) but were instead located on amide NHCO moieties in the backbone. The decrease in rate of exchange associated with acetylation paralleled a decrease in thermostability: the most slowly exchanging rungs of the charge ladder were the least thermostable (as measured by differential scanning calorimetry). This observation--that faster rates of exchange are associated with slower rates of denaturation--is contrary to the usual assumptions in protein chemistry. The fact that the rates of H/D exchange were similar for perbutyrated BCA II (e.g., [lys-ε-NHCO(CH2)2CH3]18) and peracetylated BCA II (e.g., [lys-ε-NHCOCH3]18) suggests that the electrostatic charge is more important than the hydrophobicity of surface groups in determining the rate of H/D exchange. These electrostatic effects on the kinetics of H/D exchange could complicate (or aid) the interpretation of experiments in which H/D exchange methods are used to probe the structural

  13. Pseudomonas exotoxin-mediated selection yields cells with altered expression of low-density lipoprotein receptor-related protein.

    Science.gov (United States)

    FitzGerald, D J; Fryling, C M; Zdanovsky, A; Saelinger, C B; Kounnas, M; Winkles, J A; Strickland, D; Leppla, S

    1995-06-01

    The alpha 2-macroglobulin (alpha 2M) receptor/low-density lipoprotein receptor-related protein (LRP) is important for the clearance of proteases, protease-inhibitor complexes, and various ligands associated with lipid metabolism. While the regulation of receptor function is poorly understood, the addition of high concentrations of the 39-kD receptor-associated protein (RAP) to cells inhibits the binding and/or uptake of many of these ligands. Previously, we (Kounnas, M.Z., R.E. Morris, M.R. Thompson, D.J. FitzGerald, D.K. Strickland, and C.B. Saelinger. 1992. J. Biol. Chem. 267:12420-12423) [corrected] showed that Pseudomonas exotoxin (PE) could bind immobilized LRP. Also, the addition of RAP blocked toxin-mediated cell killing. These findings suggested that PE might use LRP to gain entry into toxin-sensitive cells. Here we report on a strategy to select PE-resistant lines of Chinese hamster ovary cells that express altered amounts of LRP. An important part of this strategy is to screen PE-resistant clones for those that retain sensitivity to both diphtheria toxin and to a fusion protein composed of lethal factor (from anthrax toxin) fused to the adenosine diphosphate-ribosylating domain of PE. Two lines, with obvious changes in their expression of LRP, were characterized in detail. The 14-2-1 line had significant amounts of LRP, but in contrast to wild-type cells, little or no receptor was displayed on the cell surface. Instead, receptor protein was found primarily within cells, much of it apparently in an unprocessed state. The 14-2-1 line showed no uptake of chymotrypsin-alpha 2M and was 10-fold resistant to PE compared with wild-type cells. A second line, 13-5-1, had no detectable LRP mRNA or protein, did not internalize alpha 2M-chymotrypsin, and exhibited a 100-fold resistance to PE. Resistance to PE appeared to be due to receptor-specific defects, since these mutant lines showed no resistance to a PE chimeric toxin that was internalized via the transferrin

  14. A novel match-line selective charging scheme for high-speed, low-power and noise-tolerant content-addressable memory

    KAUST Repository

    Hasan, Muhammad Mubashwar

    2010-06-01

    Content-addressable memory (CAM) is an essential component for high-speed lookup intensive applications. This paper presents a match-line selective charging technique to increase speed and reduce the energy per bit per search while increasing the noise-tolerance. Simulation in TSMC 0.18 μm technology with 64×72 Ternary CAM shows the match-line energy reduction of 45% compared to the conventional currentsaving scheme with the reduction of minimum cycle time by 68% and the improvement of noise-tolerance by 96%.

  15. Wettability alteration: A comprehensive review of materials/methods and testing the selected ones on heavy-oil containing oil-wet systems.

    Science.gov (United States)

    Mohammed, Mohammedalmojtaba; Babadagli, Tayfun

    2015-06-01

    Changing the wetting state of materials is a growing field of research in many areas of engineering and science. In the oil industry, the term wettability alteration usually refers to the process of making the reservoir rock more water-wet. This is of particular importance in naturally hydrophobic carbonates, fractured formations, and heavy-oil systems. This shift in wettability enhances oil recovery in oil-wet and weakly water-wet reservoirs and eventually increases the ultimate oil recovery. For wettability alteration, two methods have been traditionally used: Thermal and chemical. Although many attempts have been made on reviewing the advancement of research in certain aspects of wettability, a comprehensive review of these techniques, especially in terms of the classification of the chemicals used, has been ignored. In this paper, we begin with this review and provide the past experience of wettability alteration in sandstone and carbonate reservoirs. More than 100 papers were reviewed extensively with an in-depth analysis of different methods suggested in literature. The areas of controversy and contradicted observations are discussed. The limitations and the applicability of each method were analyzed. Concerns on up-scaling laboratory findings to field scale are also addressed. The most promising potential methods are identified and their critical conditions highlighted. At the end, a selection of reviewed methods is validated experimentally for one of the most challenging cases: Extra heavy-oil and bitumen recovery from fractured-strongly-oil-wet carbonates. Berea sandstone (aged to be oil-wet) and Indiana limestone samples were saturated with heavy oil (3600cp). Next, the process was initiated by soaking the cores into solvent (heptane or diluent oil) and the oil recovery was estimated using refractive index measurements. Note that solvent was selected to dilute the oil and recover a considerable amount of oil as any chemical or thermal methods yielded

  16. HYDROTHEMAL ALTERATION MAPPING USING FEATURE-ORIENTED PRINCIPAL COMPONENT SELECTION (FPCS METHOD TO ASTER DATA:WIKKI AND MAWULGO THERMAL SPRINGS, YANKARI PARK, NIGERIA

    Directory of Open Access Journals (Sweden)

    A. J. Abubakar

    2017-10-01

    Full Text Available Geothermal systems are essentially associated with hydrothermal alteration mineral assemblages such as iron oxide/hydroxide, clay, sulfate, carbonate and silicate groups. Blind and fossilized geothermal systems are not characterized by obvious surface manifestations like hot springs, geysers and fumaroles, therefore, they could not be easily identifiable using conventional techniques. In this investigation, the applicability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER were evaluated in discriminating hydrothermal alteration minerals associated with geothermal systems as a proxy in identifying subtle Geothermal systems at Yankari Park in northeastern Nigeria. The area is characterized by a number of thermal springs such as Wikki and Mawulgo. Feature-oriented Principal Component selection (FPCS was applied to ASTER data based on spectral characteristics of hydrothermal alteration minerals for a systematic and selective extraction of the information of interest. Application of FPCS analysis to bands 5, 6 and 8 and bands 1, 2, 3 and 4 datasets of ASTER was used for mapping clay and iron oxide/hydroxide minerals in the zones of Wikki and Mawulgo thermal springs in Yankari Park area. Field survey using GPS and laboratory analysis, including X-ray Diffractometer (XRD and Analytical Spectral Devices (ASD were carried out to verify the image processing results. The results indicate that ASTER dataset reliably and complementarily be used for reconnaissance stage of targeting subtle alteration mineral assemblages associated with geothermal systems.

  17. Has enhanced folate status during pregnancy altered natural selection and possibly Autism prevalence? A closer look at a possible link.

    Science.gov (United States)

    Rogers, Eugene J

    2008-09-01

    higher frequency in Autisic individuals. It is hypothesized here that the enhancement of maternal folate status before and during pregnancy in the last 15 years has altered natural selection by increasing survival rates during pregnancy of infants possessing the MTHFR C677T polymorphism, via reduction in hyperhomocysteinemia associated with this genotype and thereby miscarriage rates. This also points directly to an increased rate of births of infants with higher postnatal requirements for folic acid needed for normal methylation during this critical neurodevelopmental period. If these numbers have increased then so have the absolute number of infants that after birth fail to maintain the higher folate status experienced in utero thus leading to an increased number of cases of developmental disorders such as Autism. Detection of the C677T polymorphism as well as other methionine cycle enzymes related to folate metabolism and methylation at birth as part of newborn screening programs could determine which newborns need be monitored and maintained on diets or supplements that ensure adequate folate status during this critical postnatal neurodevelopment period.

  18. Retentivity, selectivity and thermodynamic behavior of polycyclic aromatic hydrocarbons on charge-transfer and hypercrosslinked stationary phases under conditions of normal phase high performance liquid chromatography.

    Science.gov (United States)

    Jiang, Ping; Lucy, Charles A

    2016-03-11

    Charge-transfer and hypercrosslinked polystyrene phases offer retention and separation for polycyclic aromatic hydrocarbons (PAHs) and thus have potential for petroleum analysis. The size, shape and planarity selectivity for PAH standards on charge-transfer (DNAP column) and hypercrosslinked polystyrene (HC-Tol and 5HGN columns) phases are different under normal phase liquid chromatography (NPLC). The HC-Tol column behaves like a conventional NPLC column with low retention of PAHs. Retention of PAHs on the DNAP and 5HGN are strong and increases with the number of aromatic rings. The main retention mechanism is through π-π interactions and dipole-induced dipole interaction. Thermodynamics indicates that the retention mechanism of PAHs remains unchanged over the temperature range 20-60°C. In addition, on either DNAP or 5HGN column, both linear and bent PAHs are retained through the same mechanism. But DNAP possesses smaller π-π interaction and higher planarity selectivity than 5HGN for PAHs. This is suggestive that DNAP interacts with PAHs through a disordered phase arrangement, while 5HGN behaves as an ordered adsorption phase.

  19. Improved metabolic control does not alter the charge-dependent glomerular filtration of albumin in uncomplicated type 1 (insulin-dependent) diabetes

    DEFF Research Database (Denmark)

    Kverneland, A; Welinder, B; Feldt-Rasmussen, B

    1988-01-01

    The selectivity index, i.e. clearance of non glycated albumin/clearance of glycated albumin was studied in fourteen patients with Type 1 (insulin-dependent) diabetes and normal urinary albumin excretion. The index was increased above one in all patients, and correlated significantly to HbA1c...

  20. An altered Pseudomonas diversity is recovered from soil by using nutrient-poor Pseudomonas-selective soil extract media

    DEFF Research Database (Denmark)

    Aagot, N.; Nybroe, O.; Nielsen, P.

    2001-01-01

    . Several of these analyses showed that the amount of Casamino Acids significantly influenced the diversity of the recovered Pseudomonas isolates. Furthermore, the data suggested that specific Pseudomonas subpopulations were represented on the nutrient-poor media. The NAA 1:100 medium, containing ca. 15 mg......We designed five Pseudomonas-selective soil extract NAA media containing the selective properties of trimethoprim and sodium lauroyl sarcosine and 0 to 100% of the amount of Casamino Acids used in the classical Pseudomonas-selective Gould's S1 medium. All of the isolates were confirmed...

  1. Selective dicer suppression in the kidney alters GSK3β/β-catenin pathways promoting a glomerulocystic disease.

    Directory of Open Access Journals (Sweden)

    Anna Iervolino

    Full Text Available Dicer is a crucial enzyme for the maturation of miRNAs. Mutations in the Dicer gene are highly associated with Pleuro Pulmonary Blastoma-Family Dysplasia Syndrome (PPB-FDS, OMIM 601200, recently proposed to be renamed Dicer syndrome. Aside from the pulmonary phenotype (blastoma, renal nephroma and thyroid goiter are frequently part of Dicer syndrome. To investigate the renal phenotype, conditional knockout (cKO mice for Dicer in Pax8 expressing cells were generated. Dicer cKO mice progressively develop a glomerulocystic phenotype coupled with urinary concentration impairment, proteinuria and severe renal failure. Higher cellular turnover of the parietal cells of Bowman's capsule precedes the development of the cysts and the primary cilium progressively disappears with cyst-enlargement. Upregulation of GSK3β precedes the development of the glomerulocystic phenotype. Downregulation of β-catenin in the renal cortex and its cytosolic removal in the cells lining the cysts may be associated with observed accumulation of GSK3β. Alterations of β-catenin regulating pathways could promote cystic degeneration as in other models. Thus, miRNAs are fundamental in preserving renal morphology and function. Alteration of the GSK3β/β-catenin pathway could be a crucial mechanism linking miRNA dysregulation and the development of a glomerulocystic disease.

  2. Morphological transition of the host-structure influences solvent-relaxation: A wavelength-selective fluorescence exploration through environment-sensitive intramolecular charge transfer photophysics

    Science.gov (United States)

    Paul, Bijan Kumar; Guchhait, Nikhil

    2011-10-01

    Here, we report the modulation of photo-induced intramolecular charge transfer (ICT) photophysics of N,N-dimethylaminonaphthyl-acrylo-nitrile (DMANAN) associated with sphere-to-rod structural transition of SDS micelles induced by increasing ionic strength of the medium. Emphasis is rendered on the exploration of solvent-relaxation associated with this transition on the basis of wavelength-selective fluorescence technique which includes monitoring of red-edge excitation shift (REES) and excitation/emission anisotropy profiles. Based on micropolarity determination and organization of solvent water around the probe microenvironment we argue that the present results advocate for rod-shaped micelles to be a better mimic for membrane bilayers than spherical micelles.

  3. Selective modulation of charge-carrier transport of a photoanode in a photoelectrochemical cell by a graphitized fullerene interfacial layer.

    Science.gov (United States)

    Park, Sun-Young; Lim, Dong Chan; Hong, Eun Mi; Lee, Joo-Yeoul; Heo, Jinhee; Lim, Jae Hong; Lee, Chang-Lyoul; Kim, Young Dok; Mul, Guido

    2015-01-01

    We show that a graphitic carbon interfacial layer, derived from C70 by annealing at 500 °C, results in a significant increase in the attainable photocurrent of a photoelectrochemical cell that contains a WO3 -functionalized fluorine-doped tin oxide (FTO) photoanode. Time-resolved photoluminescence spectroscopy, photoconductive atomic force microscopy, Hall measurements, and electrochemical impedance spectroscopy show that the increase in photocurrent is the result of fast and selective electron transport from optically excited WO3 through the graphitic carbon interfacial layer to the FTO-coated glass electrode. Thus the energy efficiency of perspective solar-to-fuel devices can be improved by modification of the interface of semiconductors and conducting substrate electrodes by using graphitized fullerene derivatives.

  4. Altered Circulating Levels of Serotonin and Immunological Changes in Laying Hens Divergently Selected for Feather Pecking Behavior

    DEFF Research Database (Denmark)

    Buitenhuis, Albert Johannes; Kjaer, Jørgen B.; Labouriau, Rodrigo

    2006-01-01

    The aim of this study was to investigate the changes in immunological parameters as well as changes with respect to plasma levels of serotonin and tryptophan in lines selected for and against feather pecking (FP) behavior [high FP (HP) line and low FP (LP) line] for 5 generations. The hens from...

  5. Size-selective predation and predator-induced life-history shifts alter the outcome of competition between planktonic grazers

    NARCIS (Netherlands)

    Hülsmann, S.; Rinke, K.; Mooij, W.M.

    2011-01-01

    1.We studied the effect of size-selective predation on the outcome of competition between two differently sized prey species in a homogenous environment. 2. Using a physiologically structured population model, we calculated equilibrium food concentrations for a range of predation scenarios defined b

  6. Altered Circulating Levels of Serotonin and Immunological Changes in Laying Hens Divergently Selected for Feather Pecking Behavior

    DEFF Research Database (Denmark)

    Buitenhuis, Albert Johannes; Kjaer, Jørgen B.; Labouriau, Rodrigo

    2006-01-01

    The aim of this study was to investigate the changes in immunological parameters as well as changes with respect to plasma levels of serotonin and tryptophan in lines selected for and against feather pecking (FP) behavior [high FP (HP) line and low FP (LP) line] for 5 generations. The hens from...

  7. Titanium Oxide/Platinum Catalysis: Charge Transfer from a Titanium Oxide Support Controls Activity and Selectivity in Methanol Oxidation on Platinum

    KAUST Repository

    Hervier, Antoine

    2011-11-24

    Platinum films of 1 nm thickness were deposited by electron beam evaporation onto 100 nm thick titanium oxide films (TiOx) with variable oxygen vacancy concentrations and fluorine (F) doping. Methanol oxidation on the platinum films produced formaldehyde, methyl formate, and carbon dioxide. F-doped samples demonstrated significantly higher activity for methanol oxidation when the TiOx was stoichiometric (TiO 2), but lower activity when it was nonstoichiometric (TiO 1.7 and TiO1.9). These results correlate with the chemical behavior of the same types of catalysts in CO oxidation. Fluorine doping of stoichiometric TiO2 also increased selectivity toward partial oxidation of methanol to formaldehyde and methyl formate, but had an opposite effect in the case of nonstoichiometric TiOx. Introduction of oxygen vacancies and fluorine doping both increased the conductivity of the TiO x film. For oxygen vacancies, this occurred by the formation of a conduction channel in the band gap, whereas in the case of fluorine doping, F acted as an n-type donor, forming a conduction channel at the bottom of the conduction band, about 0.5-1.0 eV higher in energy. The higher energy electrons in F-doped stoichiometric TiOx led to higher turnover rates and increased selectivity toward partial oxidation of methanol. This correlation between electronic structure and turnover rate and selectivity indicates that the ability of the support to transfer charges to surface species controls in part the activity and selectivity of the reaction. © 2011 American Chemical Society.

  8. Klebsiella pneumoniae O antigen loss alters the outer membrane protein composition and the selective packaging of proteins into secreted outer membrane vesicles.

    Science.gov (United States)

    Cahill, Bethaney K; Seeley, Kent W; Gutel, Dedra; Ellis, Terri N

    2015-11-01

    Klebsiella pneumoniae is a nosocomial pathogen which naturally secretes lipopolysaccharide (LPS) and cell envelope associated proteins into the environment through the production of outer membrane vesicles (OMVs). The loss of the LPS O antigen has been demonstrated in other bacterial species to significantly alter the composition of OMVs. Therefore, this study aimed to comprehensively analyze the impact of O antigen loss on the sub-proteomes of both the outer membrane and secreted OMVs from K. pneumoniae. As determined by LC-MS/MS, OMVs were highly enriched with outer membrane proteins involved in cell wall, membrane, and envelope biogenesis as compared to the source cellular outer membrane. Deletion of wbbO, the enzyme responsible for O antigen attachment to LPS, decreased but did not eliminate this enrichment effect. Additionally, loss of O antigen resulted in OMVs with increased numbers of proteins involved in post-translational modification, protein turnover, and chaperones as compared to secreted vesicles from the wild type. This alteration of OMV composition may be a compensatory mechanism to deal with envelope stress. This comprehensive analysis confirms the highly distinct protein composition of OMVs as compared to their source membrane, and provides evidence for a selective sorting mechanism that involves LPS polysaccharides. These data support the hypothesis that modifications to LPS alters both the mechanics of protein sorting and the contents of secreted OMVs and significantly impacts the protein composition of the outer membrane.

  9. Exercise Training after Spinal Cord Injury Selectively Alters Synaptic Properties in Neurons in Adult Mouse Spinal Cord

    Science.gov (United States)

    Flynn, Jamie R.; Dunn, Lynda R.; Galea, Mary P.; Callister, Robin; Rank, Michelle M.

    2013-01-01

    Abstract Following spinal cord injury (SCI), anatomical changes such as axonal sprouting occur within weeks in the vicinity of the injury. Exercise training enhances axon sprouting; however, the exact mechanisms that mediate exercised-induced plasticity are unknown. We studied the effects of exercise training after SCI on the intrinsic and synaptic properties of spinal neurons in the immediate vicinity (<2 segments) of the SCI. Male mice (C57BL/6, 9–10 weeks old) received a spinal hemisection (T10) and after 1 week of recovery, they were randomized to trained (treadmill exercise for 3 weeks) and untrained (no exercise) groups. After 3 weeks, mice were killed and horizontal spinal cord slices (T6–L1, 250 μm thick) were prepared for visually guided whole cell patch clamp recording. Intrinsic properties, including resting membrane potential, input resistance, rheobase current, action potential (AP) threshold and after-hyperpolarization (AHP) amplitude were similar in neurons from trained and untrained mice (n=67 and 70 neurons, respectively). Neurons could be grouped into four categories based on their AP discharge during depolarizing current injection; the proportions of tonic firing, initial bursting, single spiking, and delayed firing neurons were similar in trained and untrained mice. The properties of spontaneous excitatory synaptic currents (sEPSCs) did not differ in trained and untrained animals. In contrast, evoked excitatory synaptic currents recorded after dorsal column stimulation were markedly increased in trained animals (peak amplitude 78.9±17.5 vs. 42.2±6.8 pA; charge 1054±376 vs. 348±75 pA·ms). These data suggest that 3 weeks of treadmill exercise does not affect the intrinsic properties of spinal neurons after SCI; however, excitatory synaptic drive from dorsal column pathways, such as the corticospinal tract, is enhanced. PMID:23320512

  10. A sensitive and selective fluorescent probe for cysteine based on a new response-assisted electrostatic attraction strategy: the role of spatial charge configuration.

    Science.gov (United States)

    Zhou, Xin; Jin, Xuejun; Sun, Guangyan; Wu, Xue

    2013-06-10

    A new strategy for fast fluorescent detection of cysteine (Cys), based on a response-assisted electrostatic attraction, is demonstrated. By utilizing this strategy, we designed and synthesized three fluorescent probes for the specific detection of Cys under actual physiological conditions. The probe m-CP, a coumarin fluorophore conjugated with a substituted methyl pyridinium group through an unsaturated ketone unit, showed highly selective and sensitive detection for cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). The kinetic analysis indicated that the sensing process was highly accelerated (a response time less than 1 min) by the response-assisted electrostatic attraction. More importantly, control experiments with isomeric probes first demonstrated that the spatial charge configuration of the probe played an important role in Cys-preferred selectivity and kinetic rate acceleration. Furthermore, the practical utility of the probe m-CP in the fluorescent labeling of Cys residues within proteins was demonstrated. Finally, these probes were employed in living cell imaging with HeLa cells, in which it displayed satisfactory cell permeability and enabled us to distinguish active thiols in the cytoplasm, nucleus, and mitochondria. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Effect of compositional alteration of food matrices and processing on availability of selected nutrients and bioactive components in rice products.

    Science.gov (United States)

    Oghbaei, Morteza; Prakash, Jamuna

    2011-05-01

    The aim was to determine the influence of compositional alteration and processing on the digestibility/availability of nutrients and bioactive components [protein (IVPD), starch (IVSD), iron, calcium, polyphenols, flavonoids] in rice products. The compositional changes representing fortified foods in 'wafers' and 'noodles' were addition of iron, rice bran, onion and cabbage. The moisture content of wafer and noodles ranged from 4.1 to 4.8% and from 73.3 to 82.1%, respectively. Wafer control (73.9-75.9%) and noodle with iron and control (85.4-87.0%) showed the highest IVPD and IVSD. Addition of rice bran decreased nutrient digestibility. The control and iron-added products exhibited least and highest available iron (2.50-2.69% and 5.99-7.07%). Total and available bioactive components increased in proportion to added external source. Overall availability of all components was better in noodles than in wafers, indicating high moisture supported higher availability. In conclusion, it can be said that both composition of the food matrix and processing influenced the availability of analyzed components.

  12. Lack of thyroid hormone receptor alpha1 is associated with selective alterations in behavior and hippocampal circuits.

    Science.gov (United States)

    Guadaño-Ferraz, A; Benavides-Piccione, R; Venero, C; Lancha, C; Vennström, B; Sandi, C; DeFelipe, J; Bernal, J

    2003-01-01

    Brain development and function are dependent on thyroid hormone (T3), which acts through nuclear hormone receptors. T3 receptors (TRs) are transcription factors that activate or suppress target gene expression in a hormone-dependent or -independent fashion. Two distinct genes, TRalpha and TRbeta, encode several receptor isoforms with specific functions defined in many tissues but not in the brain. Mutations in the TRbeta gene cause the syndrome of peripheral resistance to thyroid hormone; however, no alterations of the TRalpha gene have been described in humans. Here we demonstrate that mice lacking the TRalpha1 isoform display behavioral abnormalities of hippocampal origin, as shown by the open field and fear conditioning tests. In the open field test mutant mice revealed less exploratory behavior than wild-type mice. In the contextual fear conditioning test mutant mice showed a significantly higher freezing response than wild-type controls when tested 1 week after training. These findings correlated with fewer GABAergic terminals on the CA1 pyramidal neurons in the mutant mice. Our results indicate that TRalpha1 is involved in the regulation of hippocampal structure and function, and raise the possibility that deletions or mutations of this receptor isoform may lead to behavioral changes or even psychiatric syndromes in humans.

  13. Functional Connectivity Estimated from Resting-State fMRI Reveals Selective Alterations in Male Adolescents with Pure Conduct Disorder.

    Directory of Open Access Journals (Sweden)

    Feng-Mei Lu

    Full Text Available Conduct disorder (CD is characterized by a persistent pattern of antisocial behavior and aggression in childhood and adolescence. Previous task-based and resting-state functional magnetic resonance imaging (fMRI studies have revealed widespread brain regional abnormalities in adolescents with CD. However, whether the resting-state networks (RSNs are altered in adolescents with CD remains unknown. In this study, resting-state fMRI data were first acquired from eighteen male adolescents with pure CD and eighteen age- and gender-matched typically developing (TD individuals. Independent component analysis (ICA was implemented to extract nine representative RSNs, and the generated RSNs were then compared to show the differences between the CD and TD groups. Interestingly, it was observed from the brain mapping results that compared with the TD group, the CD group manifested decreased functional connectivity in four representative RSNs: the anterior default mode network (left middle frontal gyrus, which is considered to be correlated with impaired social cognition, the somatosensory network (bilateral supplementary motor area and right postcentral gyrus, the lateral visual network (left superior occipital gyrus, and the medial visual network (right fusiform, left lingual gyrus and right calcarine, which are expected to be relevant to the perceptual systems responsible for perceptual dysfunction in male adolescents with CD. Importantly, the novel findings suggested that male adolescents with pure CD were identified to have dysfunctions in both low-level perceptual networks (the somatosensory network and visual network and a high-order cognitive network (the default mode network. Revealing the changes in the functional connectivity of these RSNs enhances our understanding of the neural mechanisms underlying the modulation of emotion and social cognition and the regulation of perception in adolescents with CD.

  14. Functional Connectivity Estimated from Resting-State fMRI Reveals Selective Alterations in Male Adolescents with Pure Conduct Disorder.

    Science.gov (United States)

    Lu, Feng-Mei; Zhou, Jian-Song; Zhang, Jiang; Xiang, Yu-Tao; Zhang, Jian; Liu, Qi; Wang, Xiao-Ping; Yuan, Zhen

    2015-01-01

    Conduct disorder (CD) is characterized by a persistent pattern of antisocial behavior and aggression in childhood and adolescence. Previous task-based and resting-state functional magnetic resonance imaging (fMRI) studies have revealed widespread brain regional abnormalities in adolescents with CD. However, whether the resting-state networks (RSNs) are altered in adolescents with CD remains unknown. In this study, resting-state fMRI data were first acquired from eighteen male adolescents with pure CD and eighteen age- and gender-matched typically developing (TD) individuals. Independent component analysis (ICA) was implemented to extract nine representative RSNs, and the generated RSNs were then compared to show the differences between the CD and TD groups. Interestingly, it was observed from the brain mapping results that compared with the TD group, the CD group manifested decreased functional connectivity in four representative RSNs: the anterior default mode network (left middle frontal gyrus), which is considered to be correlated with impaired social cognition, the somatosensory network (bilateral supplementary motor area and right postcentral gyrus), the lateral visual network (left superior occipital gyrus), and the medial visual network (right fusiform, left lingual gyrus and right calcarine), which are expected to be relevant to the perceptual systems responsible for perceptual dysfunction in male adolescents with CD. Importantly, the novel findings suggested that male adolescents with pure CD were identified to have dysfunctions in both low-level perceptual networks (the somatosensory network and visual network) and a high-order cognitive network (the default mode network). Revealing the changes in the functional connectivity of these RSNs enhances our understanding of the neural mechanisms underlying the modulation of emotion and social cognition and the regulation of perception in adolescents with CD.

  15. Chronic intermittent ethanol exposure selectively alters the expression of Gα subunit isoforms and RGS subtypes in rat prefrontal cortex.

    Science.gov (United States)

    Luessen, D J; Sun, H; McGinnis, M M; McCool, B A; Chen, R

    2017-10-01

    Chronic alcohol exposure induces pronounced changes in GPCR-mediated G-protein signaling. Recent microarray and RNA-seq analyses suggest associations between alcohol abuse and the expression of genes involved in G-protein signaling. The activity of G-proteins (e.g. Gαi/o and Gαq) is negatively modulated by regulator of G-protein signaling (RGS) proteins which are implicated in drugs of abuse including alcohol. The present study used 7days of chronic intermittent ethanol exposure followed by 24h withdrawal (CIE) to investigate changes in mRNA and protein levels of G-protein subunit isoforms and RGS protein subtypes in rat prefrontal cortex, a region associated with cognitive deficit attributed to excessive alcohol drinking. We found that this ethanol paradigm induced differential expression of Gα subunits and RGS subtypes. For example, there were increased mRNA and protein levels of Gαi1/3 subunits and no changes in the expression of Gαs and Gαq subunits in ethanol-treated animals. Moreover, CIE increased the mRNA but not the protein levels of Gαo. Additionally, a modest increase in Gαi2 mRNA level by CIE was accompanied by a pronounced increase in its protein level. Interestingly, we found that CIE increased mRNA and protein levels of RGS2, RGS4, RGS7 and RGS19 but had no effect on the expression of RGS5, RGS6, RGS8, RGS12 or RGS17. Changes in the expression of Gα subunits and RGS subtypes could contribute to the functional alterations of certain GPCRs following chronic ethanol exposure. The present study suggests that RGS proteins may be potential new targets for intervention of alcohol abuse via modification of Gα-mediated GPCR function. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Selective destruction of nigrostriatal dopaminergic neurons does not alter [3H]-ryanodine binding in rat striatum

    Directory of Open Access Journals (Sweden)

    Noël F.

    2000-01-01

    Full Text Available Dopamine nigrostriatal neurons are important for motor control and may contain a particularly dense population of ryanodine receptors involved in the control of dopamine release. To test this hypothesis, we used a classical model of unilateral selective lesion of these neurons in rats based on 6-hydroxydopamine (6-OHDA injection into the substantia nigra. Binding of [3H]-GBR 12935, used as a presynaptic marker since it labels specifically the dopamine uptake complex, was dramatically decreased by 83-100% in striatum homogenates after 6-OHDA lesion. On the contrary, no reduction of [3H]-ryanodine binding was observed. The present data indicate that [3H]-ryanodine binding sites present in rat striatum are not preferentially localized in dopaminergic terminals.

  17. Packing interactions between transmembrane helices alter ion selectivity of the yeast Golgi Ca2+/Mn2+-ATPase PMR1.

    Science.gov (United States)

    Mandal, Debjani; Rulli, Samuel J; Rao, Rajini

    2003-09-12

    PMR1 is the yeast secretory pathway pump responsible for high affinity transport of Mn2+ and Ca2+ into the Golgi, where these ions are sequestered and effectively removed from the cytoplasm. Phenotypic growth assays allow for convenient screening of side chains important for Ca2+ and Mn2+ transport. Earlier we demonstrated that mutant Q783A at the cytoplasmic interface of M6 could transport Ca2+, but not Mn2+. Scanning mutagenesis of side chains proximal to residue Gln-783 in membrane helices M2, M4, M5, and M6 revealed additional residues near the cytoplasmic interface, notably Leu-341 (M5), Phe-738 (M5), and Leu-785 (M6) that are sensitive to substitution. Importantly, we obtained evidence for a packing interaction between Val-335 in M4 and Gln-783 in M6 that is critical for Mn2+ transport. Thus, mutant V335G mimics the Mn2+ transport defect of Q783A and mutant V335I can effectively suppress the Mn2+-defective phenotype of Q783A. These changes in ion selectivity were confirmed by cation-dependent ATP hydrolysis using purified enzyme. Other substitutions at these sites are tolerated individually, but not in combination. Exchange of side chains at 335 and 783 also results in ion selectivity defects, suggesting that the packing interaction may be conformation-sensitive. Homology models of M4, M5, and M6 of PMR1 have been generated, based on the structures of the sarcoplasmic reticulum Ca2+-ATPase. The models are supported by data from mutagenesis and reveal that Gln-783 and Val-335 show conformation-sensitive packing at the cytoplasmic interface. We suggest that this region may constitute a gate for access of Mn2+ ions.

  18. Ion-exchange and hydrophobic interactions affecting selectivity for neutral and charged solutes on three structurally similar agglomerated ion-exchange and mixed-mode stationary phases.

    Science.gov (United States)

    Kazarian, Artaches A; Taylor, Mark R; Haddad, Paul R; Nesterenko, Pavel N; Paull, Brett

    2013-11-25

    The nature and extent of mixed-mode retention mechanisms evident for three structurally related, agglomerated, particle-based stationary phases were evaluated. These three agglomerated phases were Thermo Fisher ScientificIon PacAS11-HC - strong anion exchange, Thermo Fisher Scientific IonPac CS10--strong cation-exchange PS-DVB, and the Thermo Fisher Scientific Acclaim Trinity P1silica-based substrate, which is commercially marketed as a mixed-mode stationary phase. All studied phases can exhibit zwitterionic and hydrophobic properties, which contribute to the retention of charged organic analytes. A systematic approach was devised to investigate the relative ion-exchange capacities and hydrophobicities for each of the three phases, together with the effect of eluent pH upon selectivity, using a specifically selected range of anionic, cationic and neutral aromatic compounds. Investigation of the strong anion-exchange column and the Trinity P1 mixed-mode substrate, in relation to ion-exchange capacity and pH effects, demonstrated similar retention behaviour for both the anionic and ampholytic solutes, as expected from the structurally related phases. Further evaluation revealed that the ion-exchange selectivity of the mixed-mode phase exhibited properties similar to that of the strong anion-exchange column, with secondary cation-exchange selectivity, albeit with medium to high anion-exchange and cation-exchange capacities, allowing selective retention for each of the anionic, cationic and ampholytic solutes. Observed mixed-mode retention upon the examined phases was found to be a sum of anion- and cation-exchange interactions, secondary ion-exchange and hydrophobic interactions, with possible additional hydrogen bonding. Hydrophobic evaluation of the three phases revealed logP values of 0.38-0.48, suggesting low to medium hydrophobicity. These stationary phases were also benchmarked against traditional reversed-phase substrates namely, octadecylsilica YMC-Pac Pro C18

  19. Tools for charged Higgs bosons

    Energy Technology Data Exchange (ETDEWEB)

    Staal, Oscar

    2010-12-15

    We review the status of publicly available software tools applicable to charged Higgs physics. A selection of codes are highlighted in more detail, focusing on new developments that have taken place since the previous charged Higgs workshop in 2008. We conclude that phenomenologists now have the tools ready to face the LHC data. A new web page collecting charged Higgs resources is presented. (orig.)

  20. Selective Inhibitor of Nuclear Export (SINE) Compounds Alter New World Alphavirus Capsid Localization and Reduce Viral Replication in Mammalian Cells.

    Science.gov (United States)

    Lundberg, Lindsay; Pinkham, Chelsea; de la Fuente, Cynthia; Brahms, Ashwini; Shafagati, Nazly; Wagstaff, Kylie M; Jans, David A; Tamir, Sharon; Kehn-Hall, Kylene

    2016-11-01

    The capsid structural protein of the New World alphavirus, Venezuelan equine encephalitis virus (VEEV), interacts with the host nuclear transport proteins importin α/β1 and CRM1. Novel selective inhibitor of nuclear export (SINE) compounds, KPT-185, KPT-335 (verdinexor), and KPT-350, target the host's primary nuclear export protein, CRM1, in a manner similar to the archetypical inhibitor Leptomycin B. One major limitation of Leptomycin B is its irreversible binding to CRM1; which SINE compounds alleviate because they are slowly reversible. Chemically inhibiting CRM1 with these compounds enhanced capsid localization to the nucleus compared to the inactive compound KPT-301, as indicated by immunofluorescent confocal microscopy. Differences in extracellular versus intracellular viral RNA, as well as decreased capsid in cell free supernatants, indicated the inhibitors affected viral assembly, which led to a decrease in viral titers. The decrease in viral replication was confirmed using a luciferase-tagged virus and through plaque assays. SINE compounds had no effect on VEEV TC83_Cm, which encodes a mutated form of capsid that is unable to enter the nucleus. Serially passaging VEEV in the presence of KPT-185 resulted in mutations within the nuclear localization and nuclear export signals of capsid. Finally, SINE compound treatment also reduced the viral titers of the related eastern and western equine encephalitis viruses, suggesting that CRM1 maintains a common interaction with capsid proteins across the New World alphavirus genus.

  1. Preliminary report of altered insulin secretion pattern in monochorionic twin pregnancies complicated with selective intrauterine growth restriction.

    Science.gov (United States)

    Chang, Yao-Lung; Wang, Tzu-Hao; Abufraijeh, Seham M; Chang, Shuenn-Dyh; Chao, An-Shine; Hsieh, Peter C C

    2017-02-01

    Fetuses with intrauterine growth restriction (IUGR) have adaptive hormonal changes including changes in insulin, which may increase their future risks for developing diabetes mellitus. This study compared cord blood insulin concentrations in IUGR and appropriate for gestational age (AGA) fetuses in a monochorionic (MC) twin model. Ten pairs were classified as selective IUGR (sIUGR) based on having one twin weight below the 10th percentile and with an intertwin birth weight discordance>20%. Fourteen pairs without IUGR were included as a comparison group. Pregnancies with twin-twin transfusion syndrome, congenital structural malformations, and genetic abnormalities were excluded. Insulin and glucose concentrations were measured in cord venous blood at the time of delivery. Cord blood insulin concentrations of sIUGR fetuses were significantly lower than those of AGA counterpart fetuses in MC twins affected by sIUGR (5.1±4.1 mU/L, range: 0.7-9.9 mU/L for sIUGR fetuses and 12.2±7.6 mU/L, range: 3.5-23.7 mU/L for AGA fetuses, p=0.019). No significant difference in insulin concentrations between larger and smaller fetuses in MC twins without IUGR was observed. Insulin concentration was inversely correlated with gestational age of delivery in all fetuses except in those with sIUGR. We did not find any difference in cord blood glucose concentrations between the two fetuses in both groups. Our data show reduced insulin secretion and loss of the physiological decline in concentration over time as gestational age increases in fetuses with sIUGR compared to AGA counterparts. Copyright © 2017 Taiwan Association of Obstetrics & Gynecology. Published by Elsevier B.V. All rights reserved.

  2. Glutamatergic transmission in the central nucleus of the amygdala is selectively altered in Marchigian Sardinian alcohol-preferring rats: Alcohol and CRF effects.

    Science.gov (United States)

    Herman, Melissa A; Varodayan, Florence P; Oleata, Christopher S; Luu, George; Kirson, Dean; Heilig, Markus; Ciccocioppo, Roberto; Roberto, Marisa

    2016-03-01

    The CRF system of the central nucleus of the amygdala (CeA) is important for the processing of anxiety, stress, and effects of acute and chronic ethanol. We previously reported that ethanol decreases evoked glutamate transmission in the CeA of Sprague Dawley rats and that ethanol dependence alters glutamate release in the CeA. Here, we examined the effects of ethanol, CRF and a CRF1 receptor antagonist on spontaneous and evoked glutamatergic transmission in CeA neurons from Wistar and Marchigian Sardinian Preferring (msP) rats, a rodent line genetically selected for excessive alcohol drinking and characterized by heightened activity of the CRF1 system. Basal spontaneous and evoked glutamate transmission in CeA neurons from msP rats was increased compared to Wistar rats. Ethanol had divergent effects, either increasing or decreasing spontaneous glutamate release in the CeA of Wistar rats. This bidirectional effect was retained in msP rats, but the magnitude of the ethanol-induced increase in glutamate release was significantly smaller. The inhibitory effect of ethanol on evoked glutamatergic transmission was similar in both strains. CRF also either increased or decreased spontaneous glutamate release in CeA neurons of Wistar rats, however, in msP rats CRF only increased glutamate release. The inhibitory effect of CRF on evoked glutamatergic transmission was also lost in neurons from msP rats. A CRF1 antagonist produced only minor effects on spontaneous glutamate transmission, which were consistent across strains, and no effects on evoked glutamate transmission. These results demonstrate that the genetically altered CRF system of msP rats results in alterations in spontaneous and stimulated glutamate signaling in the CeA that may contribute to both the anxiety and drinking behavioral phenotypes.

  3. Developing risk hypotheses and selecting species for assessing non-target impacts of GM trees with novel traits: the case of altered-lignin pine trees.

    Science.gov (United States)

    Malone, Louise A; Todd, Jacqui H; Burgess, Elisabeth P J; Walter, Christian; Wagner, Armin; Barratt, Barbara I P

    2010-01-01

    A procedure is presented for developing environmental risk hypotheses associated with the deployment of forest trees genetically modified to have altered wood properties and for selecting non-target species to test these hypotheses. Altered-lignin Pinus radiata trees intended for use in New Zealand are used as a hypothetical case study to illustrate our approach. Firstly, environmental management goals (such as wood production, flood control or preservation of biodiversity) were identified and linked to the forest attributes they require. Necessary conditions for each attribute were listed and appropriate assessment endpoints for them developed. For example, biological control of pests may be one condition necessary for a forest to have healthy trees, and the diversity and abundance of natural enemy species in the forest could be an appropriate assessment endpoint for measuring this condition. A conceptual model describing the relationships between an altered-lignin GM pine tree and potentially affected invertebrates and micro-organisms in a plantation forest was used to develop a set of risk hypotheses describing how the GM trees might affect each assessment endpoint. Because purified lignin does not represent the properties it imparts to wood, maximum hazard dose tests with non-target organisms, as are used to inform toxin risk assessment, cannot be conducted. Alternative experiments, based on current knowledge of the responses of organisms to lignin, must be designed. A screening method was adapted and applied to a database of invertebrate species known to inhabit New Zealand pine forests to identify and prioritize non-target invertebrate species that could be used as experimental subjects for examining these hypotheses. The screening model and its application are presented, along with a set of recommendations for pre-release tests with GM pines and potentially affected invertebrates and micro-organisms.

  4. High-Fat Diet-Induced Alterations in the Feeding Suppression of Low-Dose Nisoxetine, a Selective Norepinephrine Reuptake Inhibitor

    Directory of Open Access Journals (Sweden)

    Nicholas T. Bello

    2013-01-01

    Full Text Available Central noradrenergic pathways are involved in feeding and cardiovascular control, physiological processes altered by obesity. The present studies determined how high-fat feeding and body weight gain alter the sensitivity to the feeding suppression and neural activation to a selective norepinephrine reuptake inhibitor, nisoxetine. Acute administration of nisoxetine (saline: 0, 3, 10, and 30 mg/kg; IP resulted in a dose-dependent reduction in the 24 h refeeding response in male Sprague Dawley rats maintained on standard chow. In a similar fashion, nisoxetine resulted in reductions in blood pressure and a compensatory increase in heart rate. From these studies, the 3 mg/kg dose was subthreshold. In a separate experiment, however, 10 wk exposure to a high-fat diet (60% fat resulted in weight gain and significant feeding suppression following administration of nisoxetine (3 mg/kg compared with animals fed a control diet (10% fat. Nisoxetine (3 mg/kg also resulted in greater neural activation, as measured by c-Fos immunohistochemistry, in the arcuate nucleus of the hypothalamus in animals exposed to the high-fat diet. Such data indicate acute nisoxetine doses that suppress food intake can impact cardiovascular measures. It also suggests that the feeding suppression to a low-dose nisoxetine is enhanced as a result of high-fat diet and weight gain.

  5. High-fat diet-induced alterations in the feeding suppression of low-dose nisoxetine, a selective norepinephrine reuptake inhibitor.

    Science.gov (United States)

    Bello, Nicholas T; Walters, Amy L; Verpeut, Jessica L; Cunha, Priscila P

    2013-01-01

    Central noradrenergic pathways are involved in feeding and cardiovascular control, physiological processes altered by obesity. The present studies determined how high-fat feeding and body weight gain alter the sensitivity to the feeding suppression and neural activation to a selective norepinephrine reuptake inhibitor, nisoxetine. Acute administration of nisoxetine (saline: 0, 3, 10, and 30 mg/kg; i.p.) resulted in a dose-dependent reduction in the 24 h refeeding response in male Sprague Dawley rats maintained on standard chow. In a similar fashion, nisoxetine resulted in reductions in blood pressure and a compensatory increase in heart rate. From these studies, the 3 mg/kg dose was subthreshold. In a separate experiment, however, 10 wk exposure to a high-fat diet (60% fat) resulted in weight gain and significant feeding suppression following administration of nisoxetine (3 mg/kg) compared with animals fed a control diet (10% fat). Nisoxetine (3 mg/kg) also resulted in greater neural activation, as measured by c-Fos immunohistochemistry, in the arcuate nucleus of the hypothalamus in animals exposed to the high-fat diet. Such data indicate acute nisoxetine doses that suppress food intake can impact cardiovascular measures. It also suggests that the feeding suppression to a low-dose nisoxetine is enhanced as a result of high-fat diet and weight gain.

  6. Orbital-selective charge transfer at oxygen-deficient LaAlO3/SrTiO3(001) interfaces

    Science.gov (United States)

    Ong, P. V.; Lee, Jaichan

    2013-05-01

    Density-functional theory within the local density approximation + Hubbard U approach was used to study interface electronic structures in stoichiometric and oxygen-deficient LaAlO3/SrTiO3 (LAO/STO) superlattices with regularly spaced n-type and p-type interfaces. Asymmetric behaviors between complementary n-type and p-type interfaces were revealed in terms of orbital-selective charge transfer. Extra electrons induced by oxygen vacancies at the p-type interface easily spread to the n-type interface and occupy the Ti 3dxyorbitals, while those induced by the vacancies at the n-type interface are strictly confined and reside in Ti 3dx2-y2 and/or 3d3z2-r2 orbtials. The electronic behavior of oxygen vacancies at the LAO/STO interfaces and the possibility of distinguishing between intrinsic electronic states, which are induced by the polar catastrophe, and extrinsic states due to oxygen vacancies are discussed in detail.

  7. Neurochemical and electrophysiological deficits in the ventral hippocampus and selective behavioral alterations caused by high-fat diet in female C57BL/6 mice.

    Science.gov (United States)

    Krishna, S; Keralapurath, M M; Lin, Z; Wagner, J J; de La Serre, C B; Harn, D A; Filipov, N M

    2015-06-25

    Mounting experimental evidence, predominantly from male rodents, demonstrates that high-fat diet (HFD) consumption and ensuing obesity are detrimental to the brain. To shed additional light on the neurological consequences of HFD consumption in female rodents and to determine the relatively early impact of HFD in the likely continuum of neurological dysfunction in the context of chronic HFD intake, this study investigated effects of HFD feeding for up to 12weeks on selected behavioral, neurochemical, and electrophysiological parameters in adult female C57BL/6 mice; particular focus was placed on the ventral hippocampus (vHIP). Selected locomotor, emotional and cognitive functions were evaluated using behavioral tests after 5weeks on HFD or control (low-fat diet) diets. One week later, mice were sacrificed and brain regional neurochemical (monoamine) analysis was performed. Behaviorally naïve mice were maintained on their respective diets for an additional 5-6weeks at which time synaptic plasticity was determined in ex vivo slices from the vHIP. HFD-fed female mice exhibited increased: (i) locomotor activity in the open field testing, (ii) mean turn time on the pole test, (iii) swimming time in the forced swim test, and (iv) number of marbles buried in the marble burying test. In contrast, the novel object recognition memory was unaffected. Mice on HFD also had decreased norepinephrine and dopamine turnover, respectively, in the prefrontal cortex and the vHIP. HFD consumption for a total of 11-12weeks altered vHIP synaptic plasticity, evidenced by significant reductions in the paired-pulse ratio and long-term potentiation (LTP) magnitude. In summary, in female mice, HFD intake for several weeks induced multiple behavioral alterations of mainly anxiety-like nature and impaired monoamine pathways in a brain region-specific manner, suggesting that in the female, certain behavioral domains (anxiety) and associated brain regions, i.e., the vHIP, are preferentially

  8. High dynamic range charge measurements

    Energy Technology Data Exchange (ETDEWEB)

    De Geronimo, Gianluigi

    2012-09-04

    A charge amplifier for use in radiation sensing includes an amplifier, at least one switch, and at least one capacitor. The switch selectively couples the input of the switch to one of at least two voltages. The capacitor is electrically coupled in series between the input of the amplifier and the input of the switch. The capacitor is electrically coupled to the input of the amplifier without a switch coupled therebetween. A method of measuring charge in radiation sensing includes selectively diverting charge from an input of an amplifier to an input of at least one capacitor by selectively coupling an output of the at least one capacitor to one of at least two voltages. The input of the at least one capacitor is operatively coupled to the input of the amplifier without a switch coupled therebetween. The method also includes calculating a total charge based on a sum of the amplified charge and the diverted charge.

  9. Hydrolysed inulin alleviates the azoxymethane-induced preneoplastic aberrant crypt foci by altering selected intestinal microbiota in Sprague-Dawley rats.

    Science.gov (United States)

    Pattananandecha, Thanawat; Sirilun, Sasithorn; Duangjitcharoen, Yodsawee; Sivamaruthi, Bhagavathi Sundaram; Suwannalert, Prasit; Peerajan, Sartjin; Chaiyasut, Chaiyavat

    2016-09-01

    Context Inulin, a non-digestible carbohydrate isolated from Helianthus tuberosus L. (Asteraceae), has been shown to alter the gut beneficial bacteria including Lactobacillus spp. and Bifidobacteria. Inulin also influences the activities of intestinal microbiota that could prevent the colon cancer development. Objective This study determines the effect of hydrolysed inulin with different degrees of polymerisation on alteration of intestinal microbiota and their activities on azoxymethane (AOM)-induced preneoplastic aberrant crypt foci (ACF) in rats. Materials and methods Seventy-two male Sprague-Dawley rats were randomly divided into six groups (three control and three AOM-treated groups) and the animal were fed with either a normal diet or diet containing 10% of long-chain inulin (InuL) or short-chain inulin (InuS), respectively, for 17 weeks. Colon cancer was induced in rats by injecting AOM subcutaneously at the 8th and 9th week of the study period. At the end of the experiment, cecal contents of rats were examined for selected microbiota, organic acids, putrefactive compounds and microbial enzymes. ACF formation was microscopically examined. Results The inulin diets significantly increased the weight and decreased the pH of the caecal content. The rats fed with InuL-supplemented diet showed approximately 2.9- and 6.8-fold increases in the biomass of Lactobacillus spp. and Bifidobacteria, respectively. Naive and AOM-treated rats fed with inulin-supplemented diet showed ∼1.3- and ∼2.2-fold decreases in the biomass of Escherichia coli and Salmonella enterica serovar Typhi, respectively. Inulins significantly decreased the colonic concentration of phenol, p-cresol and indole. Reduction in the activity of microbial enzymes such as β-glucuronidase, azoreductase and nitroreductase were observed in inulin-treated animals. Reduction in the ACF formation has been observed in inulin-treated groups. Discussion and conclusion The present study demonstrates that dietary

  10. Alterations of Hair and Nail Content of Selected Trace Elements in Nonoccupationally Exposed Patients with Chronic Depression from Different Geographical Regions

    Directory of Open Access Journals (Sweden)

    Anna Błażewicz

    2017-01-01

    Full Text Available The aim of this study was to determine if altered levels of selected trace elements manifest themselves during chronic depression. To identify elements strongly associated with chronic depression, relationships between the elemental contents of hair and nails and the interelement correlations were checked. Inductively coupled plasma mass spectrometry and ion chromatography were used to evaluate the contents of Zn, Cu, Co, Pb, Mn, and Fe in hair and nail samples from a total of 415 subjects (295 patients and 120 healthy volunteers. The study included logistic regression models to predict the probability of chronic depression. To investigate possible intercorrelations among the studied elements, the scaled principal component analysis was used. The research has revealed differences in TE levels in the group of depressed men and women in comparison to the healthy subjects. Statistically significant differences in both hair and nails contents of several elements were observed. Our study also provides strong evidence that the intermediary metabolism of certain elements is age- and gender-dependent. Zn, Mn, Pb, and Fe contents in hair/nails seem to be strongly associated with chronic depression. We found no statistically significant residence-related differences in the contents of studied elements in nonoccupationally exposed patients and healthy subjects.

  11. CHARGE syndrome

    Directory of Open Access Journals (Sweden)

    Prasad Chitra

    2006-09-01

    Full Text Available Abstract CHARGE syndrome was initially defined as a non-random association of anomalies (Coloboma, Heart defect, Atresia choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies/deafness. In 1998, an expert group defined the major (the classical 4C's: Choanal atresia, Coloboma, Characteristic ears and Cranial nerve anomalies and minor criteria of CHARGE syndrome. Individuals with all four major characteristics or three major and three minor characteristics are highly likely to have CHARGE syndrome. However, there have been individuals genetically identified with CHARGE syndrome without the classical choanal atresia and coloboma. The reported incidence of CHARGE syndrome ranges from 0.1–1.2/10,000 and depends on professional recognition. Coloboma mainly affects the retina. Major and minor congenital heart defects (the commonest cyanotic heart defect is tetralogy of Fallot occur in 75–80% of patients. Choanal atresia may be membranous or bony; bilateral or unilateral. Mental retardation is variable with intelligence quotients (IQ ranging from normal to profound retardation. Under-development of the external genitalia is a common finding in males but it is less apparent in females. Ear abnormalities include a classical finding of unusually shaped ears and hearing loss (conductive and/or nerve deafness that ranges from mild to severe deafness. Multiple cranial nerve dysfunctions are common. A behavioral phenotype for CHARGE syndrome is emerging. Mutations in the CHD7 gene (member of the chromodomain helicase DNA protein family are detected in over 75% of patients with CHARGE syndrome. Children with CHARGE syndrome require intensive medical management as well as numerous surgical interventions. They also need multidisciplinary follow up. Some of the hidden issues of CHARGE syndrome are often forgotten, one being the feeding adaptation of these children, which needs an early aggressive approach from a feeding team. As the child

  12. To Establish Evaluation System for Location Selection of Electric Vehicle Charging and Swapping Station%电动汽车充(换)电站选址评价体系的构建

    Institute of Scientific and Technical Information of China (English)

    袁加妍; 潘莹; 张娥

    2014-01-01

    The problem of location selection of electric vehicle charging and swapping station is important to promote the development of electric vehicle industry.The paper introduces six principles and key factors such as social,data,economy,environmental and others that will influences location selection of electric vehicle charging and swapping station.We select the extent of coverage,economic costs,distribution of resources and service capabilities as basic index,and use AHP and FCE as the evaluation method.Through the establishment of evaluation system,we can understand the key factors of location selection of electric vehicle charging and swapping station,thereby break the bottleneck of the electric vehicle industry development.Also we should further analysis and evaluate the layout of location selection of existing and planned electric vehicle charging and swapping station scientifically.This will also give technical guidance and reference for the location selec-tion of electric vehicle charging and swapping station.%电动汽车充(换)电站的选址问题,是推进电动汽车产业化发展的一个重要问题。介绍了电动汽车充(换)电站选址的六大原则和影响选址的社会、数据、经济、环境及其他可能影响的关键因素,并且选取覆盖程度、经济成本、资源配置、服务能力作为一级指标,利用层次分析法和模糊综合评价法进行评价和分析。通过建立电动汽车充(换)电站选址评价体系,可以了解充(换)电站选址的关键因素,从而破解制约电动汽车产业化发展的瓶颈问题,并对现有及规划充(换)电站的站址布局,进行深入分析和科学评价,同时也为电动汽车大规模产业化发展下的充(换)电站的选址,进行技术指导和借鉴。

  13. Charged Leptons

    CERN Document Server

    Albrecht, J; Babu, K; Bernstein, R H; Blum, T; Brown, D N; Casey, B C K; Cheng, C -h; Cirigliano, V; Cohen, A; Deshpande, A; Dukes, E C; Echenard, B; Gaponenko, A; Glenzinski, D; Gonzalez-Alonso, M; Grancagnolo, F; Grossman, Y; Harnik, R; Hitlin, D G; Kiburg, B; Knoepfe, K; Kumar, K; Lim, G; Lu, Z -T; McKeen, D; Miller, J P; Ramsey-Musolf, M; Ray, R; Roberts, B L; Rominsky, M; Semertzidis, Y; Stoeckinger, D; Talman, R; Van De Water, R; Winter, P

    2013-01-01

    This is the report of the Intensity Frontier Charged Lepton Working Group of the 2013 Community Summer Study "Snowmass on the Mississippi", summarizing the current status and future experimental opportunities in muon and tau lepton studies and their sensitivity to new physics. These include searches for charged lepton flavor violation, measurements of magnetic and electric dipole moments, and precision measurements of the decay spectrum and parity-violating asymmetries.

  14. Altered selectivity of parathyroid hormone (PTH) and PTH-related protein (PTHrP) for distinct conformations of the PTH/PTHrP receptor.

    Science.gov (United States)

    Dean, Thomas; Vilardaga, Jean-Pierre; Potts, John T; Gardella, Thomas J

    2008-01-01

    PTH and PTHrP use the same G protein-coupled receptor, the PTH/PTHrP receptor (PTHR), to mediate their distinct biological actions. The extent to which the mechanisms by which the two ligands bind to the PTHR differ is unclear. We examined this question using several pharmacological and biophysical approaches. Kinetic dissociation and equilibrium binding assays revealed that the binding of [(125)I]PTHrP(1-36) to the PTHR was more sensitive to GTPgammaS (added to functionally uncouple PTHR-G protein complexes) than was the binding of [(125)I]PTH(1-34) ( approximately 75% maximal inhibition vs. approximately 20%). Fluorescence resonance energy transfer-based kinetic analyses revealed that PTHrP(1-36) bound to the PTHR more slowly and dissociated from it more rapidly than did PTH(1-34). The cAMP signaling response capacity of PTHrP(1-36) in cells decayed more rapidly than did that of PTH(1-34) (t(1/2) = approximately 1 vs. approximately 2 h). Divergent residue 5 in the ligand, Ile in PTH and His in PTHrP, was identified as a key determinant of the altered receptor-interaction responses exhibited by the two peptides. We conclude that whereas PTH and PTHrP bind similarly to the G protein-coupled PTHR conformation (RG), PTH has a greater capacity to bind to the G protein-uncoupled conformation (R(0)) and, hence, can produce cumulatively greater signaling responses (via R(0)-->RG isomerization) than can PTHrP. Such conformational selectivity may relate to the distinct modes by which PTH and PTHrP act biologically, endocrine vs. paracrine, and may help explain reported differences in the effects that the ligands have on calcium and bone metabolism when administered to humans.

  15. Circulating levels of endocannabinoids respond acutely to voluntary exercise, are altered in mice selectively bred for high voluntary wheel running, and differ between the sexes.

    Science.gov (United States)

    Thompson, Zoe; Argueta, Donovan; Garland, Theodore; DiPatrizio, Nicholas

    2017-03-01

    concentrations than males. For mice housed with wheels, the amount of running during the 30min before sampling was a significant positive predictor of plasma AEA within groups, and HR mice had significantly lower levels of AEA than C mice. Our results suggest that voluntary exercise alters circulating levels of endocannabinoids, and further demonstrate that selective breeding for voluntary exercise is associated with evolutionary changes in the endocannabinoid system.

  16. High Voltage Charge Pump

    KAUST Repository

    Emira, Ahmed A.

    2014-10-09

    Various embodiments of a high voltage charge pump are described. One embodiment is a charge pump circuit that comprises a plurality of switching stages each including a clock input, a clock input inverse, a clock output, and a clock output inverse. The circuit further comprises a plurality of pumping capacitors, wherein one or more pumping capacitors are coupled to a corresponding switching stage. The circuit also comprises a maximum selection circuit coupled to a last switching stage among the plurality of switching stages, the maximum selection circuit configured to filter noise on the output clock and the output clock inverse of the last switching stage, the maximum selection circuit further configured to generate a DC output voltage based on the output clock and the output clock inverse of the last switching stage.

  17. Improving cycle life of layered lithium transition metal oxide (LiMO2) based positive electrodes for Li ion batteries by smart selection of the electrochemical charge conditions

    Science.gov (United States)

    Kasnatscheew, Johannes; Evertz, Marco; Streipert, Benjamin; Wagner, Ralf; Nowak, Sascha; Cekic Laskovic, Isidora; Winter, Martin

    2017-08-01

    Increasing the specific energy of a lithium ion battery and maintaining its cycle life is a predominant goal and major challenge for electrochemical energy storage applications. Focusing on the positive electrode as the specific energy bottleneck, cycle life characteristics of promising layered oxide type active materials (LiMO2) has been thoroughly investigated. Comparing the variety of LiMO2 compositions, it could be shown that the ;Ni-rich; (Ni ≥ 60% for M in LiMO2) electrodes expectably revealed best performance compromises between specific energy and cycle life at 20 °C, but only LiNi0.6Mn0.2Co0.2O2 (NMC622) could also maintain sufficient cycle performance at elevated temperatures. Focusing on NMC622, it could be demonstrated that the applied electrochemical conditions (charge capacity, delithiation amount) in the formation cycles significantly influence the subsequent cycling performance. Moreover, the insignificant transition metal dissolution, demonstrated by means of total X-ray fluorescence (TXRF) technique, and unchanged lithiation degree in the discharged state, determined by the measurement of the Li+ content by means of the inductively coupled plasma optical emission spectroscopy (ICP-OES) technique, pointed to a delithiation (charge) hindrance capacity fade mechanism. Considering these insights, thoughtful modifications of the electrochemical charge conditions could significantly prolong the cycle life.

  18. Review on modified TiO2 photocatalysis under UV/visible light: selected results and related mechanisms on interfacial charge carrier transfer dynamics.

    Science.gov (United States)

    Kumar, S Girish; Devi, L Gomathi

    2011-11-24

    Titania is one of the most widely used benchmark standard photocatalysts in the field of environmental applications. However, the large band gap of titania and massive recombination of photogenerated charge carriers limit its overall photocatalytic efficiency. The former can be overcome by modifying the electronic band structure of titania including various strategies like coupling with a narrow band gap semiconductor, metal ion/nonmetal ion doping, codoping with two or more foreign ions, surface sensitization by organic dyes or metal complexes, and noble metal deposition. The latter can be corrected by changing the surface properties of titania by fluorination or sulfation or by the addition of suitable electron acceptors besides molecular oxygen in the reaction medium. This review encompasses several advancements made in these aspects, and also some of the new physical insights related to the charge transfer events like charge carrier generation, trapping, detrapping, and their transfer to surface are discussed for each strategy of the modified titania to support the conclusions derived. The synergistic effects in the mixed polymorphs of titania and also the theories proposed for their enhanced activity are reported. A recent venture on the synthesis and applications of anatase titania with a large percentage of reactive {001} facets and their band gap extension to the visible region via nonmetal ion doping which is a current hot topic is briefly outlined.

  19. Complete Charging for Piezoelectric Energy Harvesting System

    Institute of Scientific and Technical Information of China (English)

    樊康旗; 徐春辉; 王卫东

    2014-01-01

    Under an in-phase assumption, the complete charging for an energy harvesting system is studied, which consists of a piezoelectric energy harvester (PEH), a bridge rectifier, a filter capacitor, a switch, a controller and a rechargeable battery. For the transient charging, the results indicate that the voltage across the filter capacitor increases as the charging proceeds, which is consistent with that reported in the literature. However, a new finding shows that the charging rate and energy harvesting efficiency decrease over time after their respective peak values are acquired. For the steady-state charging, the results reveal that the energy harvesting efficiency can be adjusted by altering the critical charging voltage that controls the transition of the system. The optimal energy harvesting efficiency is limited by the optimal efficiency of the transient charging. Finally, the relationship between the critical charging voltage and the equivalent resistance of the controller and rechargeable battery is established explicitly.

  20. Dopant selection for control of charge carrier density and mobility in amorphous indium oxide thin-film transistors: Comparison between Si- and W-dopants

    Science.gov (United States)

    Mitoma, Nobuhiko; Aikawa, Shinya; Ou-Yang, Wei; Gao, Xu; Kizu, Takio; Lin, Meng-Fang; Fujiwara, Akihiko; Nabatame, Toshihide; Tsukagoshi, Kazuhito

    2015-01-01

    The dependence of oxygen vacancy suppression on dopant species in amorphous indium oxide (a-InOx) thin film transistors (TFTs) is reported. In a-InOx TFTs incorporating equivalent atom densities of Si- and W-dopants, absorption of oxygen in the host a-InOx matrix was found to depend on difference of Gibbs free energy of the dopants for oxidation. For fully oxidized films, the extracted channel conductivity was higher in the a-InOx TFTs containing dopants of small ionic radius. This can be explained by a reduction in the ionic scattering cross sectional area caused by charge screening effects.

  1. Cox4i2, Ifit2, and Prdm11 Mutant Mice: Effective Selection of Genes Predisposing to an Altered Airway Inflammatory Response from a Large Compendium of Mutant Mouse Lines.

    Science.gov (United States)

    Horsch, Marion; Aguilar-Pimentel, Juan Antonio; Bönisch, Clemens; Côme, Christophe; Kolster-Fog, Cathrine; Jensen, Klaus T; Lund, Anders H; Lee, Icksoo; Grossman, Lawrence I; Sinkler, Christopher; Hüttemann, Maik; Bohn, Erwin; Fuchs, Helmut; Ollert, Markus; Gailus-Durner, Valérie; de Angelis, Martin Hrabĕ; Beckers, Johannes

    2015-01-01

    We established a selection strategy to identify new models for an altered airway inflammatory response from a large compendium of mutant mouse lines that were systemically phenotyped in the German Mouse Clinic (GMC). As selection criteria we included published gene functional data, as well as immunological and transcriptome data from GMC phenotyping screens under standard conditions. Applying these criteria we identified a few from several hundred mutant mouse lines and further characterized the Cox4i2tm1Hutt, Ifit2tm1.1Ebsb, and Prdm11tm1.1ahl lines following ovalbumin (OVA) sensitization and repeated OVA airway challenge. Challenged Prdm11tm1.1ahl mice exhibited changes in B cell counts, CD4+ T cell counts, and in the number of neutrophils in bronchoalveolar lavages, whereas challenged Ifit2tm1.1Ebsb mice displayed alterations in plasma IgE, IgG1, IgG3, and IgM levels compared to the challenged wild type littermates. In contrast, challenged Cox4i2tm1Hutt mutant mice did not show alterations in the humoral or cellular immune response compared to challenged wild type mice. Transcriptome analyses from lungs of the challenged mutant mouse lines showed extensive changes in gene expression in Prdm11tm1.1ahl mice. Functional annotations of regulated genes of all three mutant mouse lines were primarily related to inflammation and airway smooth muscle (ASM) remodeling. We were thus able to define an effective selection strategy to identify new candidate genes for the predisposition to an altered airway inflammatory response under OVA challenge conditions. Similar selection strategies may be used for the analysis of additional genotype-envirotype interactions for other diseases.

  2. Electrical Double Layer and Charge Regulation for a Homotattic Surface

    Science.gov (United States)

    Zhmud; House

    1997-03-15

    The spatial distribution of the electrostatic potential near a charge-regulated homotattic surface containing zones with altering ionization ability is studied in the framework of the Debye approximation. In contrast to the constant-charge case traditionally discussed in the literature, charge regulation causes inhomogeneity of the surface charge distribution within each zone at the surface. Possible methods of solution of the charge regulation problem are outlined, and the results of a model calculation are reported.

  3. Construction Machinery Depreciation Method Selection Based on Final Value of Depreciation Charges%基于终值的工程机械折旧方法探讨

    Institute of Scientific and Technical Information of China (English)

    袁吉

    2016-01-01

    Taking the shield machine as an example, this paper uses composite life method and the annual summation method to calculate depreciation charges. Through calculation and comparison, we found total amount of depreciation charge and tax unchanged, the time of depreciation and taxes different, lead to the final cost of depreciation and tax amount appeared the 8.1% difference. Through comparative analysis, we found that the annual summation method is very beneficial for enterprises of construction machinery update because the final cost of depreciation value increased. In the case of constant total tax , tax time was pushed back,and the burden of the enterprise is reduced.%以盾构机为例,分别采用平均年限法和年数总和法计提折旧费,通过计算对比,发现分别采用两种折旧方法时,折旧费计提总额和税金总额不变,但因折旧费和税金发生的时点不同,导致折旧费和税金的终值出现了8.1%的差值。通过对比分析,发现采用加速折旧法时折旧费的终值增加对于企业工程机械的更新非常有利,在不减少企业纳税总额同时,也推迟了企业纳税的时间,减轻了企业的负担。

  4. Temporal Alterations in the Secretome of the Selective Ligninolytic Fungus Ceriporipsis subvermispora during growth on Aspen Wood Reveal this Organism's Strategy for Degrading Lighnocellulose

    Science.gov (United States)

    Chiaki Hori; Jill Gaskell; Kiyohiko Igarashi; Phil Kersten; Michael Mozuch; Masahiro Samejima; Dan Cullen

    2014-01-01

    The white-rot basidiomycetes efficiently degrade all wood cell wall polymers. Generally, these fungi simultaneously degrade cellulose and lignin, but certain organisms, such as Ceriporiopsis subvermispora, selectively remove lignin in advance of cellulose degradation. However, relatively little is known about themechanismof selective ligninolysis. To...

  5. Collaborative Mobile Charging and Coverage

    Institute of Scientific and Technical Information of China (English)

    吴杰

    2014-01-01

    Wireless energy charging using mobile vehicles has been a viable research topic recently in the area of wireless networks and mobile computing. This paper gives a short survey of recent research conducted in our research group in the area of collaborative mobile charging. In collaborative mobile charging, multiple mobile chargers work together to accomplish a given set of ob jectives. These ob jectives include charging sensors at different frequencies with a minimum number of mobile chargers and reaching the farthest sensor for a given set of mobile chargers, subject to various constraints, including speed and energy limits of mobile chargers. Through the process of problem formulation, solution construction, and future work extension for problems related to collaborative mobile charging and coverage, we present three principles for good practice in conducting research. These principles can potentially be used for assisting graduate students in selecting a research problem for a term project, which can eventually be expanded to a thesis/dissertation topic.

  6. Raman-Mössbauer-XRD studies of selected samples from "Los Azulejos" outcrop: A possible analogue for assessing the alteration processes on Mars

    Science.gov (United States)

    Lalla, E. A.; Sanz-Arranz, A.; Lopez-Reyes, G.; Sansano, A.; Medina, J.; Schmanke, D.; Klingelhoefer, G.; Rodríguez-Losada, J. A.; Martínez-Frías, J.; Rull, F.

    2016-06-01

    The outcrop of "Los Azulejos" is visible at the interior of the Cañadas Caldera in Tenerife Island (Spain). It exhibits a great variety of alteration processes that could be considered as terrestrial analogue for several geological processes on Mars. This outcrop is particularly interesting due to the content of clays, zeolite, iron oxides, and sulfates corresponding to a hydrothermal alteration catalogued as "Azulejos" type alteration. A detailed analysis by portable and laboratory Raman systems as well as other different techniques such as X-ray diffraction (XRD) and Mössbauer spectroscopy has been carried out (using twin-instruments from Martian lander missions: Mössbauer spectrometer MIMOS-II from the NASA-MER mission of 2001 and the XRD diffractometer from the NASA-MSL Curiosity mission of 2012). The mineral identification presents the following mineral species: magnetite, goethite, hematite, anatase, rutile, quartz, gregoryite, sulfate (thenardite and hexahydrite), diopside, feldspar, analcime, kaolinite and muscovite. Moreover, the in-situ Raman and Micro-Raman measurements have been performed in order to compare the capabilities of the portable system specially focused for the next ESA Exo-Mars mission. The mineral detection confirms the sub-aerial alteration on the surface and the hydrothermal processes by the volcanic fluid circulations in the fresh part. Therefore, the secondary more abundant mineralization acts as the color agent of the rocks. Thus, the zeolite-illite group is the responsible for the bluish coloration, as well as the feldspars and carbonates for the whitish and the iron oxide for the redish parts. The XRD system was capable to detect a minor proportion of pyroxene, which is not visible by Raman and Mössbauer spectroscopy due to the "Azulejos" alteration of the parent material on the outcrop. On the other hand, Mössbauer spectroscopy was capable of detecting different types of iron-oxides (Fe3+/2+-oxide phases). These analyses

  7. Charge Qubit-Atom Hybrid

    CERN Document Server

    Yu, Deshui; Hufnagel, C; Kwek, L C; Amico, Luigi; Dumke, R

    2016-01-01

    We investigate a novel hybrid system of a superconducting charge qubit interacting directly with a single neutral atom via electric dipole coupling. Interfacing of the macroscopic superconducting circuit with the microscopic atomic system is accomplished by varying the gate capacitance of the charge qubit. To achieve strong interaction, we employ two Rydberg states with an electric-dipole-allowed transition, which alters the polarizability of the dielectric medium of the gate capacitor. Sweeping the gate voltage with different rates leads to a precise control of hybrid quantum states. Furthermore, we show a possible implementation of a universal two-qubit gate.

  8. Altered catalytic activity of and DNA cleavage by DNA topoisomerase II from human leukemic cells selected for resistance to VM-26.

    Science.gov (United States)

    Danks, M K; Schmidt, C A; Cirtain, M C; Suttle, D P; Beck, W T

    1988-11-29

    The simultaneous development of resistance to the cytotoxic effects of several classes of natural product anticancer drugs, after exposure to only one of these agents, is referred to as multiple drug resistance (MDR). At least two distinct mechanisms for MDR have been postulated: that associated with P-glycoprotein and that thought to be due to an alteration in DNA topoisomerase II activity (at-MDR). We describe studies with two sublines of human leukemic CCRF-CEM cells approximately 50-fold resistant (CEM/VM-1) and approximately 140-fold resistant (CEM/VM-1-5) to VM-26, a drug known to interfere with DNA topoisomerase II activity. Each of these lines is cross-resistant to other drugs known to affect topoisomerase II but not cross-resistant to vinblastine, an inhibitor of mitotic spindle formation. We found little difference in the amount of immunoreactive DNA topoisomerase II in 1.0 M NaCl nuclear extracts of the two resistant and parental cell lines. However, topoisomerase II in nuclear extracts of the resistant sublines is altered in both catalytic activity (unknotting) of and DNA cleavage by this enzyme. Also, the rate at which catenation occurs is 20-30-fold slower with the CEM/VM-1-5 preparations. The effect of VM-26 on both strand passing and DNA cleavage is inversely related to the degree of primary resistance of each cell line. Our data support the hypothesis that at-MDR is due to an alteration in topoisomerase II or in a factor modulating its activity.

  9. Fluoxetine, a selective inhibitor of serotonin uptake, potentiates morphine analgesia without altering its discriminative stimulus properties or affinity for opioid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Hynes, M.D.; Lochner, M.A.; Bemis, K.G.; Hymson, D.L.

    1985-06-17

    The analgesic effect of morphine in the rat tail jerk assay was enhanced by the serotonin uptake inhibitor, fluoxetine. Tail jerk latency was not affected by fluoxetine alone. Morphine's affinity for opioid receptors labeled in vitro with /sup 3/H-naloxone or /sup 3/H-D-Ala/sup 2/-D-Leu/sup 5/-enkephalin was not altered by fluoxetine, which has no affinity for these sites at concentrations as high as 1000 nM. In rats trained to discriminate morphine from saline, fluoxetine at doses of 5 or 10 mg/kg were recognized as saline. Increasing the fluoxetine dose to 20 mg/kg did not result in generalization to either saline or morphine. The dose response curve for morphine generalization was not significantly altered by fluoxetine doses of 5 or 10 mg/kg. Those rats treated with the combination of morphine and 20 mg/kg of fluoxetine did not exhibit saline or morphine appropriate responding. Fluoxetine potentiates the analgesic properties of morphine without enhancing its affinity for opioid receptors or its discriminative stimulus properties. 30 references, 2 figures, 2 tables.

  10. Simulation and optimization of site and capacity selection in the planning of charge infrastructure for battery electric vehicle fleets; Simulation und Optimierung der Standort- und Kapazitaetsauswahl in der Planung von Ladeinfrastruktur fuer batterieelektrische Fahrzeugflotten

    Energy Technology Data Exchange (ETDEWEB)

    Siefen, Kostja

    2012-07-15

    Political, technological and economic factors have led to a new upswing in the development of Electric Mobility. In addition to the private sector, certain industrial fleets are especially suited as pilot customers for battery electric vehicles. Economic advantages compared to conventional vehicles are caused by low energy costs if vehicles reach high mileage and still have enough time to recharge the needed energy. To supply energy to all fleet vehicles, a proper charging infrastructure has to be available in the operational area. The focus of this work is the development of new simulation and optimization models for this strategic planning task. The developed simulation model allows a detailed analysis and evaluation of the impact of various business models. It allows the variation of the fleet size, the vehicle types, the battery capacity, the infrastructure configuration and charging rules in the operational concept. The developed optimization model allows the cost-minimal selection of supply locations and their capacity to ensure the required quality of service. For medium and large problem instances exact solution methods reach their limits, so that a separate heuristic method is presented. The developed methods were used in a real project to demonstrate the practicality.

  11. CHARGE Association

    Directory of Open Access Journals (Sweden)

    Semanti Chakraborty

    2012-01-01

    Full Text Available We present here a case of 17-year-old boy from Kolkata presenting with obesity, bilateral gynecomastia, mental retardation, and hypogonadotrophic hypogonadism. The patient weighed 70 kg and was of 153 cm height. Facial asymmetry (unilateral facial palsy, gynecomastia, decreased pubic and axillary hair, small penis, decreased right testicular volume, non-palpable left testis, and right-sided congenital inguinal hernia was present. The patient also had disc coloboma, convergent squint, microcornea, microphthalmia, pseudohypertelorism, low set ears, short neck, and choanalatresia. He had h/o VSD repaired with patch. Laboratory examination revealed haemoglobin 9.9 mg/dl, urea 24 mg/dl, creatinine 0.68 mg/dl. IGF1 77.80 ng/ml (decreased for age, GH <0.05 ng/ml, testosterone 0.25 ng/ml, FSH-0.95 ΅IU/ml, LH 0.60 ΅IU/ml. ACTH, 8:00 A.M cortisol, FT3, FT4, TSH, estradiol, DHEA-S, lipid profile, and LFT was within normal limits. Prolactin was elevated at 38.50 ng/ml. The patient′s karyotype was 46XY. Echocardiography revealed ventricularseptal defect closed with patch, grade 1 aortic regurgitation, and ejection fraction 67%. Ultrasound testis showed small right testis within scrotal sac and undescended left testis within left inguinal canal. CT scan paranasal sinuses revealed choanalatresia and deviation of nasal septum to the right. Sonomammography revealed bilateral proliferation of fibroglandular elements predominantly in subareoalar region of breasts. MRI of brain and pituitary region revealed markedly atrophic pituitary gland parenchyma with preserved infundibulum and hypothalamus and widened suprasellar cistern. The CHARGE association is an increasingly recognized non-random pattern of congenital anomalies comprising of coloboma, heart defect, choanal atresia, retarded growth and development, genital hypoplasia, ear abnormalities, and/or deafness. [1] These anomalies have a higher probability of occurring together. In this report, we have

  12. Charge selective contact on ultra-thin In(OH){sub x}S {sub y}/Pb(OH) {sub x}S {sub y} heterostructure prepared by SILAR

    Energy Technology Data Exchange (ETDEWEB)

    Gavrilov, S.; Oja, I.; Lim, B.; Belaidi, A.; Bohne, W.; Strub, E.; Roehrich, J.; Lux-Steiner, M.-Ch.; Dittrich, Th. [Hahn-Meitner-Institut, Glienicker Str. 100, 14109 Berlin (Germany)

    2006-04-15

    Ultra-thin In(OH){sub x}S{sub y}/Pb(OH){sub x}S {sub y} heterostructures were formed by the wet chemical SILAR (successive ion layer adsorption and reaction) technique. ERDA (elastic recoil detection analysis) was used for stoichiometry analysis. The heterocontacts were conditioned by joint annealing of the two layers at different low temperatures in air. The charge selectivity was demonstrated with various small area solar cell structures. The results are discussed on the base of formation of bonds between sulphide clusters and passivation of defects with hydrogen containing species in hydroxy-sulphides. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  13. The net charge at interfaces between insulators

    Science.gov (United States)

    Bristowe, N. C.; Littlewood, P. B.; Artacho, Emilio

    2011-03-01

    The issue of the net charge at insulating oxide interfaces is briefly reviewed with the ambition of dispelling myths of such charges being affected by covalency and related charge density effects. For electrostatic analysis purposes, the net charge at such interfaces is defined by the counting of discrete electrons and core ion charges, and by the definition of the reference polarization of the separate, unperturbed bulk materials. The arguments are illustrated for the case of a thin film of LaAlO3 over SrTiO3 in the absence of free carriers, for which the net charge is exactly 0.5e per interface formula unit, if the polarization response in both materials is referred to zero bulk values. Further consequences of the argument are extracted for structural and chemical alterations of such interfaces, in which internal rearrangements are distinguished from extrinsic alterations (changes of stoichiometry, redox processes), only the latter affecting the interfacial net charge. The arguments are reviewed alongside the proposal of Stengel and Vanderbilt (2009 Phys. Rev. B 80 241103) of using formal polarization values instead of net interfacial charges, based on the interface theorem of Vanderbilt and King-Smith (1993 Phys. Rev. B 48 4442-55). Implications for non-centrosymmetric materials are discussed, as well as for interfaces for which the charge mismatch is an integer number of polarization quanta.

  14. The intermolecular interaction in D2 - CX4 and O2 - CX4 (X = F, Cl) systems: Molecular beam scattering experiments as a sensitive probe of the selectivity of charge transfer component

    Science.gov (United States)

    Cappelletti, David; Falcinelli, Stefano; Pirani, Fernando

    2016-10-01

    Gas phase collisions of a D2 projectile by CF4 and by CCl4 targets have been investigated with the molecular beam technique. The integral cross section, Q, has been measured for both collisional systems in the thermal energy range and oscillations due to the quantum "glory" interference have been resolved in the velocity dependence of Q. The analysis of the measured Q(v) data provided novel information on the anisotropic potential energy surfaces of the studied systems at intermediate and large separation distances. The relative role of the most relevant types of contributions to the global interaction has been characterized. Extending the phenomenology of a weak intermolecular halogen bond, the present work demonstrates that while D2 - CF4 is basically bound through the balance between size (Pauli) repulsion and dispersion attraction, an appreciable intermolecular bond stabilization by charge transfer is operative in D2 - CCl4. We also demonstrated that the present analysis is consistent with that carried out for the F(2P)-D2 and Cl(2P)-D2 systems, previously characterized by scattering experiments performed with state-selected halogen atom beams. A detailed comparison of the present and previous results on O2-CF4 and O2-CCl4 systems pinpointed striking differences in the behavior of hydrogen and oxygen molecules when they interact with the same partner, mainly due to the selectivity of the charge transfer component. The present work contributes to cast light on the nature and role of the intermolecular interaction in prototype systems, involving homo-nuclear diatoms and symmetric halogenated molecules.

  15. 核电厂铅酸蓄电池充放电方式分析%The Analysis for Selection of the Lead-acid Battery Charging and Discharging Method

    Institute of Scientific and Technical Information of China (English)

    刘宇; 李波; 孔凡华

    2015-01-01

    蓄电池作为直流系统的最后一道保护屏障,其运行状况、性能是直流系统安全稳定运行的决定性因素,而充放电试验是验证蓄电池运行状况的基本方法.文章以某核电铅酸蓄电池为例,着重介绍了铅酸蓄电池在不同工况下的充放电方式.通过查阅相关文献、调查研究并结合现场实际情况,对不同工况下蓄电池的充放电方式进行了确认;同时对不同充放电方式的适用范围及其优缺点进行了分析,为铅酸蓄电池组设计了合理的充放电方式选用方法,为铅酸蓄电池的安全稳定运行打下了坚实的基础.%The operation of battery,as the last barrier of DC system,determines the stable op-eration of the DC system. Capacity test is the basic way to verify the battery performance. This article takes the lead-acid battery of Fuqing Nuclear Power Plant as example,shows the different charging and discharging modes. The charging and discharging modes under different conditions are confirmed depending on relevant literature,investigation and the actual situation. The advantages and disadvantages of different charging and discharging modes,and also the scope of application are discussed in this paper. Areasonable charging and discharging method forlead-acid batteries is selected,which laid a solid foundation for the safe and stable operation of lead-acid battery.

  16. Dielectric charging by an electron beam

    Science.gov (United States)

    Upatov, V. Y.

    1996-08-01

    Experimental discovery of a charge spot field effect (CSFE) has altered considerably our understanding of dielectric charging by an electron beam, under conditions typical for the operation of a large class of cathode ray tubes (CRT). Dielectric charging by an electron beam was studied using a specific pulse method for the measurement of the potential. The accuracy of this method is discussed. Measurements were made of the potential relief of a positively charged spot on muscovite mica (quartz, aluminum oxide). The potential at the spot center, under conditions described in the paper and at a relatively long charging time, was shown to be considerably lower than that of the collector. Potential dependence on charging time, determined under the same conditions, is shown for the charged spot center and a number of adjacent points. During creation of the charged spot charging current was measured. The results of the measurements are discussed. A new mechanism of dielectric charging by electron beam is proposed. A CSFE is formulated, and its significance for the operation of CRT is stated. Criticism is given of in-plane grid effect. The paper presents calculations of fields for grid target models determining the mechanism of dielectric charging by electron beam.

  17. Network based management for multiplexed electric vehicle charging

    Energy Technology Data Exchange (ETDEWEB)

    Gadh, Rajit; Chung, Ching Yen; Qui, Li

    2017-04-11

    A system for multiplexing charging of electric vehicles, comprising a server coupled to a plurality of charging control modules over a network. Each of said charging modules being connected to a voltage source such that each charging control module is configured to regulate distribution of voltage from the voltage source to an electric vehicle coupled to the charging control module. Data collection and control software is provided on the server for identifying a plurality of electric vehicles coupled to the plurality of charging control modules and selectively distributing charging of the plurality of charging control modules to multiplex distribution of voltage to the plurality of electric vehicles.

  18. SLAP deficiency increases TCR avidity leading to altered repertoire and negative selection of cognate antigen-specific CD8+ T cells.

    Science.gov (United States)

    Friend, Samantha F; Peterson, Lisa K; Kedl, Ross M; Dragone, Leonard L

    2013-03-01

    How T cell receptor (TCR) avidity influences CD8(+) T cell development and repertoire selection is not yet fully understood. To fill this gap, we utilized Src-like adaptor protein (SLAP)-deficient mice as a tool to increase TCR avidity on double positive (DP) thymocytes. We generated SLAP(-/-) mice with the transgenic MHC class I-restricted TCR (OT-1) and SLAP(-/-) Vβ5 mice, expressing only the β-chain of the TCR OT-1 transgene, to examine the effects of increased TCR surface levels on CD8(+) T cell development and repertoire selection. In comparing SLAP(-/-) OT-1 and Vβ5 mice with wild-type controls, we performed compositional analysis and assessed thymocyte signaling by measuring CD5 levels. In addition, we performed tetramer and compositional staining to measure affinity for the cognate antigen, ovalbumin (OVA) peptide, presented by MHC. Furthermore, we quantified differences in α-chain repertoire in SLAP(-/-) Vβ5 mice. We have found that SLAP(-/-) OT-1 mice have fewer CD8(+) thymocytes but have increased CD5 expression. SLAP(-/-) OT-1 mice have fewer DP thymocytes expressing Vα2, signifying increased endogenous α-chain rearrangement, and more non-OVA-specific CD8(+) splenocytes upon tetramer staining. Our data demonstrate that SLAP(-/-) Vβ5 mice also have fewer OVA-specific cells and increased Vα2 usage in the peripheral Vβ5 CD8(+) T cells that were non-OVA-specific, demonstrating differences in α-chain repertoire. These studies provide direct evidence that increased TCR avidity in DP thymocytes enhances CD8(+) T cell negative selection deleting thymocytes with specificity for cognate antigen, an antigen the mature T cells may never encounter. Collectively, these studies provide new insights into how TCR avidity during CD8(+) T cell development influences repertoire selection.

  19. Field Driven Charging Dynamics of a Fluidized Granular Bed

    CERN Document Server

    Yoshimatsu, R; Shinbrot, T; Herrmann, H J

    2016-01-01

    A simplified model has previously described the inductive charging of colliding identical grains in the presence of an external electric field. Here we extend that model by including heterogeneous surface charge distributions, grain rotations and electrostatic interactions between grains. We find from this more realistic model that strong heterogeneities in charging can occur in agitated granular beds, and we predict that shielding due to these heterogeneities can dramatically alter the charging rate in such beds.

  20. Workplace Charging. Charging Up University Campuses

    Energy Technology Data Exchange (ETDEWEB)

    Giles, Carrie [ICF International, Fairfax, VA (United States); Ryder, Carrie [ICF International, Fairfax, VA (United States); Lommele, Stephen [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-01

    This case study features the experiences of university partners in the U.S. Department of Energy's (DOE) Workplace Charging Challenge with the installation and management of plug-in electric vehicle (PEV) charging stations.

  1. High motivation for exercise is associated with altered chromatin regulators of monoamine receptor gene expression in the striatum of selectively bred mice.

    Science.gov (United States)

    Saul, M C; Majdak, P; Perez, S; Reilly, M; Garland, T; Rhodes, J S

    2017-03-01

    Although exercise is critical for health, many lack the motivation to exercise, and it is unclear how motivation might be increased. To uncover the molecular underpinnings of increased motivation for exercise, we analyzed the transcriptome of the striatum in four mouse lines selectively bred for high voluntary wheel running and four non-selected control lines. The striatum was dissected and RNA was extracted and sequenced from four individuals of each line. We found multiple genes and gene systems with strong relationships to both selection and running history over the previous 6 days. Among these genes were Htr1b, a serotonin receptor subunit and Slc38a2, a marker for both glutamatergic and γ-aminobutyric acid (GABA)-ergic signaling. System analysis of the raw results found enrichment of transcriptional regulation and kinase genes. Further, we identified a splice variant affecting the Wnt-related Golgi signaling gene Tmed5. Using coexpression network analysis, we found a cluster of interrelated coexpression modules with relationships to running behavior. From these modules, we built a network correlated with running that predicts a mechanistic relationship between transcriptional regulation by nucleosome structure and Htr1b expression. The Library of Integrated Network-Based Cellular Signatures identified the protein kinase C δ inhibitor, rottlerin, the tyrosine kinase inhibitor, Linifanib and the delta-opioid receptor antagonist 7-benzylidenenaltrexone as potential compounds for increasing the motivation to run. Taken together, our findings support a neurobiological framework of exercise motivation where chromatin state leads to differences in dopamine signaling through modulation of both the primary neurotransmitters glutamate and GABA, and by neuromodulators such as serotonin. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  2. In vitro resistance selections for Plasmodium falciparum dihydroorotate dehydrogenase inhibitors give mutants with multiple point mutations in the drug-binding site and altered growth.

    Science.gov (United States)

    Ross, Leila S; Gamo, Francisco Javier; Lafuente-Monasterio, Maria José; Singh, Onkar M P; Rowland, Paul; Wiegand, Roger C; Wirth, Dyann F

    2014-06-27

    Malaria is a preventable and treatable disease; yet half of the world's population lives at risk of infection, and an estimated 660,000 people die of malaria-related causes every year. Rising drug resistance threatens to make malaria untreatable, necessitating both the discovery of new antimalarial agents and the development of strategies to identify and suppress the emergence and spread of drug resistance. We focused on in-development dihydroorotate dehydrogenase (DHODH) inhibitors. Characterizing resistance pathways for antimalarial agents not yet in clinical use will increase our understanding of the potential for resistance. We identified resistance mechanisms of Plasmodium falciparum (Pf) DHODH inhibitors via in vitro resistance selections. We found 11 point mutations in the PfDHODH target. Target gene amplification and unknown mechanisms also contributed to resistance, albeit to a lesser extent. These mutant parasites were often hypersensitive to other PfDHODH inhibitors, which immediately suggested a novel combination therapy approach to preventing resistance. Indeed, a combination of wild-type and mutant-type selective inhibitors led to resistance far less often than either drug alone. The effects of point mutations in PfDHODH were corroborated with purified recombinant wild-type and mutant-type PfDHODH proteins, which showed the same trends in drug response as the cognate cell lines. Comparative growth assays demonstrated that two mutant parasites grew less robustly than their wild-type parent, and the purified protein of those mutants showed a decrease in catalytic efficiency, thereby suggesting a reason for the diminished growth rate. Co-crystallography of PfDHODH with three inhibitors suggested that hydrophobic interactions are important for drug binding and selectivity.

  3. Explosive bulk charge

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Jacob Lee

    2015-04-21

    An explosive bulk charge, including: a first contact surface configured to be selectively disposed substantially adjacent to a structure or material; a second end surface configured to selectively receive a detonator; and a curvilinear side surface joining the first contact surface and the second end surface. The first contact surface, the second end surface, and the curvilinear side surface form a bi-truncated hemispherical structure. The first contact surface, the second end surface, and the curvilinear side surface are formed from an explosive material. Optionally, the first contact surface and the second end surface each have a substantially circular shape. Optionally, the first contact surface and the second end surface consist of planar structures that are aligned substantially parallel or slightly tilted with respect to one another. The curvilinear side surface has one of a smooth curved geometry, an elliptical geometry, and a parabolic geometry.

  4. Coaxial charged particle energy analyzer

    Science.gov (United States)

    Kelly, Michael A. (Inventor); Bryson, III, Charles E. (Inventor); Wu, Warren (Inventor)

    2011-01-01

    A non-dispersive electrostatic energy analyzer for electrons and other charged particles having a generally coaxial structure of a sequentially arranged sections of an electrostatic lens to focus the beam through an iris and preferably including an ellipsoidally shaped input grid for collimating a wide acceptance beam from a charged-particle source, an electrostatic high-pass filter including a planar exit grid, and an electrostatic low-pass filter. The low-pass filter is configured to reflect low-energy particles back towards a charged particle detector located within the low-pass filter. Each section comprises multiple tubular or conical electrodes arranged about the central axis. The voltages on the lens are scanned to place a selected energy band of the accepted beam at a selected energy at the iris. Voltages on the high-pass and low-pass filters remain substantially fixed during the scan.

  5. Mild stress induces brain region-specific alterations of selective ER stress markers' mRNA expression in Wfs1-deficient mice.

    Science.gov (United States)

    Altperery, A; Raud, S; Sütt, S; Reimets, R; Visnapuu, T; Toots, M; Vasar, E

    2017-09-26

    In this work, the effect of mild stress (elevated plus maze test, EPM) on the expression of endoplasmic reticulum (ER) stress markers in different brain areas of wild type (WT) and Wfs1-deficient (Wfs1KO) mice was investigated. The following ER stress markers were studied: activating transcription factor 6α (Atf6α), protein kinase-like ER kinase (Perk), X-box binding protein 1 (Xbp1) and its spliced form (Xbp1s), 78-kilodalton glucose regulated protein (Grp78), 94-kilodalton glucose regulated protein (Grp94), C/EBP homologous protein (Chop). Wfs1KO and WT mice, not exposed to EPM, had similar patterns of ER stress markers in the studied brain areas. The exploratory activity of Wfs1KO mice in the EPM was inhibited compared to WT mice, probably reflecting increased anxiety in genetically modified mice. In response to the EPM, activation of inositol-requiring transmembrane kinase and endonuclease 1α (Ire1α) ER stress pathway was seen in both genotypes, but in different brain areas. Such a brain region-specific Ire1α activation was linked with dominant behavioural trends in these mice as more anxious, neophobic Wfs1KO mice had increased ER stress markers expression in the temporal lobe, the brain region related to anxiety, and more curious WT mice had ER stress markers increased in the ventral striatum which is related to the exploratory drive. The molecular mechanism triggering respective changes in ER stress markers in these brain regions is likely related to altered levels of monoamine neurotransmitters (serotonin, dopamine) in Wfs1KO mice. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Altered Ca2+ kinetics associated with α-actinin-3 deficiency may explain positive selection for ACTN3 null allele in human evolution.

    Science.gov (United States)

    Head, Stewart I; Chan, Stephen; Houweling, Peter J; Quinlan, Kate G R; Murphy, Robyn; Wagner, Sören; Friedrich, Oliver; North, Kathryn N

    2015-01-01

    Over 1.5 billion people lack the skeletal muscle fast-twitch fibre protein α-actinin-3 due to homozygosity for a common null polymorphism (R577X) in the ACTN3 gene. α-Actinin-3 deficiency is detrimental to sprint performance in elite athletes and beneficial to endurance activities. In the human genome, it is very difficult to find single-gene loss-of-function variants that bear signatures of positive selection, yet intriguingly, the ACTN3 null variant has undergone strong positive selection during recent evolution, appearing to provide a survival advantage where food resources are scarce and climate is cold. We have previously demonstrated that α-actinin-3 deficiency in the Actn3 KO mouse results in a shift in fast-twitch fibres towards oxidative metabolism, which would be more "energy efficient" in famine, and beneficial to endurance performance. Prolonged exposure to cold can also induce changes in skeletal muscle similar to those observed with endurance training, and changes in Ca2+ handling by the sarcoplasmic reticulum (SR) are a key factor underlying these adaptations. On this basis, we explored the effects of α-actinin-3 deficiency on Ca2+ kinetics in single flexor digitorum brevis muscle fibres from Actn3 KO mice, using the Ca2+-sensitive dye fura-2. Compared to wild-type, fibres of Actn3 KO mice showed: (i) an increased rate of decay of the twitch transient; (ii) a fourfold increase in the rate of SR Ca2+ leak; (iii) a threefold increase in the rate of SR Ca2+ pumping; and (iv) enhanced maintenance of tetanic Ca2+ during fatigue. The SR Ca2+ pump, SERCA1, and the Ca2+-binding proteins, calsequestrin and sarcalumenin, showed markedly increased expression in muscles of KO mice. Together, these changes in Ca2+ handling in the absence of α-actinin-3 are consistent with cold acclimatisation and thermogenesis, and offer an additional explanation for the positive selection of the ACTN3 577X null allele in populations living in cold environments during recent

  7. Altered Ca2+ kinetics associated with α-actinin-3 deficiency may explain positive selection for ACTN3 null allele in human evolution.

    Directory of Open Access Journals (Sweden)

    Stewart I Head

    Full Text Available Over 1.5 billion people lack the skeletal muscle fast-twitch fibre protein α-actinin-3 due to homozygosity for a common null polymorphism (R577X in the ACTN3 gene. α-Actinin-3 deficiency is detrimental to sprint performance in elite athletes and beneficial to endurance activities. In the human genome, it is very difficult to find single-gene loss-of-function variants that bear signatures of positive selection, yet intriguingly, the ACTN3 null variant has undergone strong positive selection during recent evolution, appearing to provide a survival advantage where food resources are scarce and climate is cold. We have previously demonstrated that α-actinin-3 deficiency in the Actn3 KO mouse results in a shift in fast-twitch fibres towards oxidative metabolism, which would be more "energy efficient" in famine, and beneficial to endurance performance. Prolonged exposure to cold can also induce changes in skeletal muscle similar to those observed with endurance training, and changes in Ca2+ handling by the sarcoplasmic reticulum (SR are a key factor underlying these adaptations. On this basis, we explored the effects of α-actinin-3 deficiency on Ca2+ kinetics in single flexor digitorum brevis muscle fibres from Actn3 KO mice, using the Ca2+-sensitive dye fura-2. Compared to wild-type, fibres of Actn3 KO mice showed: (i an increased rate of decay of the twitch transient; (ii a fourfold increase in the rate of SR Ca2+ leak; (iii a threefold increase in the rate of SR Ca2+ pumping; and (iv enhanced maintenance of tetanic Ca2+ during fatigue. The SR Ca2+ pump, SERCA1, and the Ca2+-binding proteins, calsequestrin and sarcalumenin, showed markedly increased expression in muscles of KO mice. Together, these changes in Ca2+ handling in the absence of α-actinin-3 are consistent with cold acclimatisation and thermogenesis, and offer an additional explanation for the positive selection of the ACTN3 577X null allele in populations living in cold environments

  8. Selective factors governing in vitro β-carotene bioaccessibility: negative influence of low filtration cutoffs and alterations by emulsifiers and food matrices.

    Science.gov (United States)

    Corte-Real, Joana; Richling, Elke; Hoffmann, Lucien; Bohn, Torsten

    2014-12-01

    Because of their putative health benefits, the biological fate of carotenoids after digestion has been met with much interest, and ex vivo methods using carotenoid standards to study their digestion and further metabolism have been developed. In the absence of a complex food matrix, that is, when studying isolated carotenoids, protocol conditions of gastrointestinal digestion models have to be adjusted. In this investigation, we hypothesized that certain selected factors would significantly influence the bioaccessibility of β-carotene in vitro. The factors considered included (i) type of lipid matrix employed (milk, cream, or oil), (ii) presence/absence of emulsifiers (e.g. lecithin and taurocholate), (iii) addition of a gastric lipase, and (iv) final filtration (20 or 200 nm) of the digesta. Adding an emulsifier mixture (10 mg lecithin + 50 mg monoolein + 5 mg oleic acid) enhanced β-carotene bioaccessibility 3 times (P emulsifier and matrix should be considered. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Alterações fenotípicas em cultivares de alface selecionadas para calor Phenotypical alterations in lettuce genotypes selected for heat tolerance

    Directory of Open Access Journals (Sweden)

    José Henrique Conti

    2000-11-01

    Full Text Available Cultivares de alface selecionadas para o pendoamento lento e as mesmas que lhes deram origem foram analisadas quanto a variações morfológicas, com o objetivo de quantificar possíveis modificações adaptativas para as condições de cultivo em épocas de calor. Cultivares dos grupos "manteiga" (Regina, Glória, IAC 303, IAC 202, Sem Rival e Luciana "folha crespa" (Grand Rapids e Brisa e "americana" (Great Lakes e Mesa 659, foram avaliadas em dois plantios de verão, em Piracicaba, em delineamento de blocos casualizados. No primeiro experimento, (novembro/90, foram avaliadas as características de número de estômatos, espessura de folha e quantidade de clorofila total. No segundo, (setembro/91, foram avaliados o peso seco, peso fresco, porcentagem de matéria seca, tempo para pendoamento e número de folhas. As cultivares selecionadas para calor no grupo "manteiga" (Glória e Regina, apresentaram maior número de estômatos (respectivamente 9487/cm² e 7973/cm² e folhas mais grossas (respectivamente 556 mm e 439 mm e também, acumularam maior quantidade de matéria seca (respectivamente 24,55 g e 25,50 g. A cultivar selecionada para calor do grupo "folha crespa" (Brisa acumulou maior quantidade de matéria verde (446,77g e seca (22,40 g, da mesma forma que apresentou maior quantidade de estômatos (7.279/cm². Para as cultivares do grupo "americana", observou-se diferença significativa apenas para espessura de folha, sendo que a cultivar Mesa 659 apresentou folhas mais grossas (589 mm. Constataram-se aumentos significativos da biomassa vegetal nas cultivares selecionadas para calor em relação àquelas não selecionadas. As cultivares que atingiram maior produtividade de matéria seca por planta foram Mesa 659 (28,74 g, Great Lakes (27,17 g e Regina. Os resultados comprovaram que a seleção para o pendoamento lento indiretamente produziu variações adaptativas nas plantas de alface.Lettuce cultivars selected for slow bolting and

  10. Propofol selectively alters GluA1 AMPA receptor phosphorylation in the hippocampus but not prefrontal cortex in young and aged mice

    Science.gov (United States)

    Mao, Li-Min; Hastings, James M.; Fibuch, Eugene E; Wang, John Q.

    2014-01-01

    Propofol is a commonly used general anesthetic agent which has been previously shown to enhance the inhibitory GABAergic transmission in the central nervous system. In addition to the GABAergic element, the excitatory transmission may be another central molecular site impacted by propofol. Increasing evidence implies that the alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor represents an excitatory amino acid receptor subtype subjected to the regulation by propofol. Indeed, in this study, we found that a single injection of propofol at an anesthetic dose increased AMPA receptor GluA1 subunit phosphorylation in young (2–3 months old) and aged (20–21 months old) mice in vivo. Propofol caused an increase in GluA1 phosphorylation in the hippocampus but not in the prefrontal cortex. The propofol effect was also site-selective as the drug elevated GluA1 phosphorylation at serine 831 (S831) but not serine 845. Interestingly, while propofol induced a moderate and transient increase in S831 phosphorylation in young mice, the drug caused a substantial and sustained S831 phosphorylation in aged animals. Total GluA1 abundance remained stable in the hippocampus and prefrontal cortex in both young and aged mice in response to propofol. These results provide evidence supporting the sensitivity of GluA1 AMPA receptors to propofol. A single dose of propofol was able to upregulate GluA1 phosphorylation in the confined hippocampus in an age-dependent manner. PMID:24907515

  11. PE11 (Rv1169c Selectively Altering Fatty Acid Components of Mycobacterium smegmatis and Host interleukin-6 Level Accompany with Cell Death

    Directory of Open Access Journals (Sweden)

    Wanyan eDeng

    2015-06-01

    Full Text Available PE/PPE family proteins, named after their conserved PE (Pro-Glu and PPE (Pro-Pro-Glu domains of N-terminal, are most intriguing aspects of pathologic mycobacterial genome. The roles of most members of this family remain unknown, although selected genes of this family are related to the virulence of Mycobacterium tuberculosis. In order to decipher the role of Rv1169c, the Mycobacterium smegmatis strain heterologously expressed this ORF was constructed and identified that Rv1169c was a cell wall associated protein with a novel function in modifying the cell wall fatty acid component.. The growth of Rv1169c expressing strain was affected under surface stress, acidic condition and antibiotics norfloxacin and rifampicin treatment. M. smegmatis expressing Rv1169c induced necrotic cell death of macrophage after infection and significantly decreased interlukin-6 production compared to controls. In general, these results underscore a proposing role of Rv1169c in virulence of M. tuberculosis, as it’s role in the susceptibility of anti-mycobacteria factors caused by modified cell wall fatty acid, and the induced necrotic cell death by Rv1169c is crucial for M. tuberculosis virulence during infection.

  12. Selective translational repression of HIV-1 RNA by Sam68DeltaC occurs by altering PABP1 binding to unspliced viral RNA

    Directory of Open Access Journals (Sweden)

    Soros Vanessa

    2008-10-01

    Full Text Available Abstract HIV-1 structural proteins are translated from incompletely spliced 9 kb and 4 kb mRNAs, which are transported to the cytoplasm by Crm1. It has been assumed that once in the cytoplasm, translation of incompletely spliced HIV-1 mRNAs occurs in the same manner as host mRNAs. Previous analyses have demonstrated that Sam68 and a mutant thereof, Sam68ΔC, have dramatic effects on HIV gene expression, strongly enhancing and inhibiting viral structural protein synthesis, respectively. While investigating the inhibition of incompletely spliced HIV-1 mRNAs by Sam68ΔC, we determined that the effect was independent of the perinuclear bundling of the viral RNA. Inhibition was dependent upon the nuclear export pathway used, as translation of viral RNA exported via the Tap/CTE export pathway was not blocked by Sam68ΔC. We demonstrate that inhibition of HIV expression by Sam68ΔC is correlated with a loss of PABP1 binding with no attendant change in polyadenosine tail length of the affected RNAs. The capacity of Sam68ΔC to selectively inhibit translation of HIV-1 RNAs exported by Crm1 suggests that it is able to recognize unique characteristics of these viral RNPs, a property that could lead to new therapeutic approaches to controlling HIV-1 replication.

  13. PRMT5 Is Upregulated in HTLV-1-Mediated T-Cell Transformation and Selective Inhibition Alters Viral Gene Expression and Infected Cell Survival

    Directory of Open Access Journals (Sweden)

    Amanda R. Panfil

    2015-12-01

    Full Text Available Human T-cell leukemia virus type-1 (HTLV-1 is a tumorigenic retrovirus responsible for development of adult T-cell leukemia/lymphoma (ATLL. This disease manifests after a long clinical latency period of up to 2–3 decades. Two viral gene products, Tax and HBZ, have transforming properties and play a role in the pathogenic process. Genetic and epigenetic cellular changes also occur in HTLV-1-infected cells, which contribute to transformation and disease development. However, the role of cellular factors in transformation is not completely understood. Herein, we examined the role of protein arginine methyltransferase 5 (PRMT5 on HTLV-1-mediated cellular transformation and viral gene expression. We found PRMT5 expression was upregulated during HTLV-1-mediated T-cell transformation, as well as in established lymphocytic leukemia/lymphoma cell lines and ATLL patient PBMCs. shRNA-mediated reduction in PRMT5 protein levels or its inhibition by a small molecule inhibitor (PRMT5i in HTLV-1-infected lymphocytes resulted in increased viral gene expression and decreased cellular proliferation. PRMT5i also had selective toxicity in HTLV-1-transformed T-cells. Finally, we demonstrated that PRMT5 and the HTLV-1 p30 protein had an additive inhibitory effect on HTLV-1 gene expression. Our study provides evidence for PRMT5 as a host cell factor important in HTLV-1-mediated T-cell transformation, and a potential target for ATLL treatment.

  14. Comparative study of the effect of BPA and its selected analogues on hemoglobin oxidation, morphological alterations and hemolytic changes in human erythrocytes.

    Science.gov (United States)

    Maćczak, Aneta; Bukowska, Bożena; Michałowicz, Jaromir

    2015-01-01

    Bisphenol A (BPA) has been shown to provoke many deleterious impacts on human health, and thus it is now successively substituted by BPA analogues, whose effects have been poorly investigated. Up to now, only one study has been realized to assess the effect of BPA on human erythrocytes, which showed its significant hemolytic and oxidative potential. Moreover, no study has been conducted to evaluate the effect of BPA analogues on red blood cells. The purpose of the present study was to compare the impact of BPA and its selected analogues such as bisphenol F (BPF), bisphenol S (BPS) and bisphenol AF (BPAF) on hemolytic and morphological changes and hemoglobin oxidation (methemoglobin formation) of human erythrocytes. The erythrocytes were incubated with different bisphenols concentrations ranging from 0.5 to 500μg/ml for 1, 4 and 24h. The compounds examined caused hemolysis in human erythrocytes with BPAF exhibiting the strongest effect. All bisphenols examined caused methemoglobin formation with BPA inducing the strongest oxidative potential. Flow cytometry analysis showed that all bisphenols (excluding BPS) induced significant changes in erythrocytes size. Changes in red blood cells shape were conducted using phase contrast microscopy. It was noticed that BPA and BPAF induced echinocytosis, BPF caused stomatocytosis, while BPS did not provoke significant changes in shape of red blood cells. Generally, the results showed that BPS, which is the main substituent of bisphenol A in polymers and thermal paper production, exhibited significantly lower disturbance of erythrocyte functions than BPA.

  15. PRMT5 Is Upregulated in HTLV-1-Mediated T-Cell Transformation and Selective Inhibition Alters Viral Gene Expression and Infected Cell Survival.

    Science.gov (United States)

    Panfil, Amanda R; Al-Saleem, Jacob; Howard, Cory M; Mates, Jessica M; Kwiek, Jesse J; Baiocchi, Robert A; Green, Patrick L

    2015-12-30

    Human T-cell leukemia virus type-1 (HTLV-1) is a tumorigenic retrovirus responsible for development of adult T-cell leukemia/lymphoma (ATLL). This disease manifests after a long clinical latency period of up to 2-3 decades. Two viral gene products, Tax and HBZ, have transforming properties and play a role in the pathogenic process. Genetic and epigenetic cellular changes also occur in HTLV-1-infected cells, which contribute to transformation and disease development. However, the role of cellular factors in transformation is not completely understood. Herein, we examined the role of protein arginine methyltransferase 5 (PRMT5) on HTLV-1-mediated cellular transformation and viral gene expression. We found PRMT5 expression was upregulated during HTLV-1-mediated T-cell transformation, as well as in established lymphocytic leukemia/lymphoma cell lines and ATLL patient PBMCs. shRNA-mediated reduction in PRMT5 protein levels or its inhibition by a small molecule inhibitor (PRMT5i) in HTLV-1-infected lymphocytes resulted in increased viral gene expression and decreased cellular proliferation. PRMT5i also had selective toxicity in HTLV-1-transformed T-cells. Finally, we demonstrated that PRMT5 and the HTLV-1 p30 protein had an additive inhibitory effect on HTLV-1 gene expression. Our study provides evidence for PRMT5 as a host cell factor important in HTLV-1-mediated T-cell transformation, and a potential target for ATLL treatment.

  16. Detecting Site-Specific Physicochemical Selective Pressures: Applications to the Class I HLA of the Human Major Histocompatibility Complex and the SRK of the Plant Sporophytic Self-Incompatibility System

    DEFF Research Database (Denmark)

    Sainudiin, Raazesh; Wong, Wendy Shuk Wan; Yogeeswaran, Krithika

    2005-01-01

    plants (Brassicaceae), whose structure is unknown. Through likelihood ratio tests we demonstrate that at some sites, the positively selected MHC and SRK proteins are under physicochemical selective pressures to alter polarity, volume, polarity and/or volume, and charge to various extents. An empirical...... Bayes approach is used to identify sites that may be important for ligand recognition in these proteins....

  17. Changing dietary calcium-phosphorus level and cereal source selectively alters abundance of bacteria and metabolites in the upper gastrointestinal tracts of weaned pigs.

    Science.gov (United States)

    Metzler-Zebeli, Barbara U; Mann, Evelyne; Schmitz-Esser, Stephan; Wagner, Martin; Ritzmann, Mathias; Zebeli, Qendrim

    2013-12-01

    Several dietary ingredients may affect the bacterial community structure and metabolism in the porcine gut and may therefore influence animals' health and performance. This study investigated the effects of cereal source and calcium-phosphorus (CaP) level in the diet on bacterial microbiota and metabolites, nutrient intake, and gut environment in weaned pigs. Pigs (n=8/treatment) were fed wheat-barley- or corn-based diets with an adequate or high CaP level for 14 days. Effects on microbiota in the stomach, ileum, and midcolon were assessed using quantitative PCR. Data showed that Enterobacteriaceae, Campylobacter spp., and Helicobacter spp., which all contain highly immune reactive lipopolysaccharide (LPS), were abundant at all gut sites. Diet effects on bacteria and metabolites were moderate and occurred mainly in the upper gut, whereas no effects on bacteria, fermentation products, and LPS could be observed in the colon. Differences in carbohydrate intake with corn versus wheat-barley diets selectively stimulated Bifidobacterium in the stomach and ileum. There was a growth advantage for a few bacterial groups in the stomach and ileum of pigs fed the high versus adequate CaP level (i.e., gastric Enterobacteriaceae and ileal Enterococcus, Bacteroides-Prevotella-Porphyromonas, and Campylobacter). Interestingly, gastrointestinal pH was not affected by dietary CaP level. The present findings demonstrate the stability of the bacterial community and gut environment toward dietary changes even in young pigs. The results on stimulation of gastric and ileal Bifidobacterium by corn diets may be employed in nutritional strategies to support gut health after weaning.

  18. Expression of the human apolipoprotein A-I gene in transgenic mice alters high density lipoprotein (HDL) particle size distribution and diminishes selective uptake of HDL cholesteryl esters

    Energy Technology Data Exchange (ETDEWEB)

    Chajekshaul, T.; Hayek, T.; Walsh, A.; Breslow, J.L. (Rockefeller University, New York, NY (USA))

    1991-08-01

    Transgenic mice carrying the human apolipoprotein (apo) A-I gene (HuAITg mice) were used to examine the effects of overexpression of the human gene on high density lipoprotein (HDL) particle size distribution and metabolism. On a chow diet, control mice had HDL cholesterol and apo A-I levels of 49 {plus minus} 2 and 137 {plus minus} 12 mg/dl of plasma, respectively. HuAITg mice had HDL cholesterol, human apo A-I, and mouse apo A-I levels of 88 {plus minus} 2, 255 {plus minus} 19, and 16 {plus minus} 2 mg/dl, respectively. Nondenaturing gradient gel electrophoresis revealed control mouse plasma HDL to be primarily monodisperse with a particle diameter of 10.2 nm, whereas HuAITg mouse plasma HDL was polydisperse with particles of diameter 11.4, 10.2, and 8.7 nm, which correspond in size to human HDL1, HDL2, and HDL3, respectively. In vivo turnover studies of HDL labeled with (3H)cholesteryl linoleyl ether and 125I-apo A-I were performed. In control animals, the fractional catabolic rate (FCR) for HDL cholesteryl ester was significantly more than the apo A-I FCR. In the HuAITg mice, the HDL cholesteryl ester FCR was the same as the apo A-I FCR. There were no significant differences between control and HuAITg animals in the sites of tissue removal of HDL cholesteryl ester, with the liver extracting most of the injected radioactivity. Control and HuAITg animals had comparable liver and intestinal cholesterol synthesis and LDL FCR. In conclusion, HuAITg mice have principally human and not mouse apo A-I in their plasma. This apparently causes a change in HDL particle size distribution in the transgenic mice to one resembling the human pattern. The replacement of mouse by human apo A-I also apparently causes the loss of the selective uptake pathway of HDL cholesteryl esters present in control mice.

  19. Perinatal exposure to the selective serotonin reuptake inhibitor citalopram alters spatial learning and memory, anxiety, depression, and startle in Sprague-Dawley rats.

    Science.gov (United States)

    Sprowles, Jenna L N; Hufgard, Jillian R; Gutierrez, Arnold; Bailey, Rebecca A; Jablonski, Sarah A; Williams, Michael T; Vorhees, Charles V

    2016-11-01

    Selective serotonin reuptake inhibitors (SSRIs) block the serotonin (5-HT) reuptake transporter (SERT) and increase synaptic 5-HT. 5-HT is also important in brain development; hence when SSRIs are taken during pregnancy there exists the potential for these drugs to affect CNS ontogeny. Prenatal SSRI exposure has been associated with an increased prevalence of autism spectrum disorder (ASD), and peripheral 5-HT is elevated in some ASD patients. Perinatal SSRI exposure in rodents has been associated with increased depression and anxiety-like behavior, decreased sociability, and impaired learning in the offspring, behaviors often seen in ASD. The present study investigated whether perinatal exposure to citalopram causes persistent neurobehavioral effects. Gravid Sprague-Dawley rats were assigned to two groups and subcutaneously injected twice per day with citalopram (10mg/kg; Cit) or saline (Sal) 6h apart on embryonic day (E)6-21, and then drug was given directly to the pups after delivery from postnatal day (P)1-20. Starting on P60, one male/female from each litter was tested in the Cincinnati water maze (CWM) and open-field before and after MK-801. A second pair from each litter was tested in the Morris water maze (MWM) and open-field before and after (+)-amphetamine. A third pair was tested as follows: elevated zero-maze, open-field, marble burying, prepulse inhibition of acoustic startle, social preference, and forced swim. Cit-exposed rats were impaired in the MWM during acquisition and probe, but not during reversal, shift, or cued trials. Cit-exposed rats also showed increased marble burying, decreased time in the center of the open-field, decreased latency to immobility in forced swim, and increased acoustic startle across prepulse intensities with no effects on CWM. The results are consistent with citalopram inducing several ASD-like effects. The findings add to concerns about use of SSRIs during pregnancy. Further research on different classes of

  20. Battery charging system

    Energy Technology Data Exchange (ETDEWEB)

    Carollo, J.A.; Kalinsky, W.A.

    1984-02-21

    A battery charger utilizes three basic modes of operation that includes a maintenance mode, a rapid charge mode and time controlled limited charging mode. The device utilizes feedback from the battery being charged of voltage, current and temperature to determine the mode of operation and the time period during which the battery is being charged.

  1. Magnetic charge quantisation and fractionally charged quarks

    NARCIS (Netherlands)

    Hooft, G. 't

    1976-01-01

    If magnetic monopoles with Schwinger's value of the magnetic charge would exist then that would pose serious restrictions on theories with fractionally charged quarks, even if they are confined. Weak and electromagnetic interactions must be unified with color, leading to a Weinberg angle w close to

  2. Charge Transfer and Catalysis at the Metal Support Interface

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Lawrence Robert [Univ. of California, Berkeley, CA (United States)

    2012-07-31

    Kinetic, electronic, and spectroscopic characterization of model Pt–support systems are used to demonstrate the relationship between charge transfer and catalytic activity and selectivity. The results show that charge flow controls the activity and selectivity of supported metal catalysts. This dissertation builds on extensive existing knowledge of metal–support interactions in heterogeneous catalysis. The results show the prominent role of charge transfer at catalytic interfaces to determine catalytic activity and selectivity. Further, this research demonstrates the possibility of selectively driving catalytic chemistry by controlling charge flow and presents solid-state devices and doped supports as novel methods for obtaining electronic control over catalytic reaction kinetics.

  3. Charging for differentiated Internet services

    Science.gov (United States)

    Stiller, Burkhard; Gerke, Jan; Hasan, Hasan; Reichl, Peter; Flury, Placi

    2001-07-01

    Internet communications today play a major role in data transport within the local as well as the wide area. On one hand, since emerging networked applications require a variety of different communication services, the number of service classes offered by service providers has to be targeted at this demand. On the other hand, assuming that a set of different traffic classes are offered by service providers, the 'right' incentives have to be provided, ensuring that applications or their users select the most appropriate traffic class. Even though users are considered to be selective, they intend to chose that class which offers the best available Quality-of-Service (QoS), as long as the price to be paid does not exceed their willingness-to-pay. Therefore, charging for differentiated Internet services is important in a commercialized Internet. The current Internet does not cater for charging at all, since the technology required, the pricing models going beyond a flat-fee approach, and the appropriate efficiency in technical as well as economic terms are still missing on a global basis. This paper outlines the major problems for charging Internet services and describes briefly an important new solution for a pricing approach, which solves the Internet pricing feasibility problem. Based on these preconditions an Internet Charging System (ICS) is introduced, focusing mainly on its leading characteristics and its generic approach to instantiate for a given scenario.

  4. Electrical charging of ash in Icelandic volcanic plumes

    CERN Document Server

    Aplin, Karen L; Nicoll, Keri A

    2014-01-01

    The existence of volcanic lightning and alteration of the atmospheric potential gradient in the vicinity of near-vent volcanic plumes provides strong evidence for the charging of volcanic ash. More subtle electrical effects are also visible in balloon soundings of distal volcanic plumes. Near the vent, some proposed charging mechanisms are fractoemission, triboelectrification, and the so-called "dirty thunderstorm" mechanism, which is where ash and convective clouds interact electrically to enhance charging. Distant from the vent, a self-charging mechanism, probably triboelectrification, has been suggested to explain the sustained low levels of charge observed on a distal plume. Recent research by Houghton et al. (2013) linked the self-charging of volcanic ash to the properties of the particle size distribution, observing that a highly polydisperse ash distribution would charge more effectively than a monodisperse one. Natural radioactivity in some volcanic ash could also contribute to self-charging of volcan...

  5. Influence of surface charge on wetting kinetics.

    Science.gov (United States)

    Puah, Lee San; Sedev, Rossen; Fornasiero, Daniel; Ralston, John; Blake, Terry

    2010-11-16

    The wettability of a titania surface, partially covered with octadecyltrihydrosilane, has been investigated as a function of solution pH. The results show that surface charge affects both static wettability and wetting kinetics. The static contact angle decreases above and below the point of zero charge of the titania surface in a Lippman-like manner as the pH is altered. The dependence of dynamic contact angle on velocity is also affected by pH. The molecular-kinetic theory (MKT) is used to interpret the dynamic contact angle data. The frequency of molecular displacement κ(0) strongly varies with surface charge, whereas the mean molecular displacement length λ is essentially unaffected. There is an exponential dependence of contact-line friction upon work of adhesion, which is varied simply by altering the pH.

  6. Higher magnesium intake is associated with lower fasting glucose and insulin, with no evidence of interaction with select genetic loci, in a meta-analysis of 15 CHARGE Consortium Studies.

    Science.gov (United States)

    Hruby, Adela; Ngwa, Julius S; Renström, Frida; Wojczynski, Mary K; Ganna, Andrea; Hallmans, Göran; Houston, Denise K; Jacques, Paul F; Kanoni, Stavroula; Lehtimäki, Terho; Lemaitre, Rozenn N; Manichaikul, Ani; North, Kari E; Ntalla, Ioanna; Sonestedt, Emily; Tanaka, Toshiko; van Rooij, Frank J A; Bandinelli, Stefania; Djoussé, Luc; Grigoriou, Efi; Johansson, Ingegerd; Lohman, Kurt K; Pankow, James S; Raitakari, Olli T; Riserus, Ulf; Yannakoulia, Mary; Zillikens, M Carola; Hassanali, Neelam; Liu, Yongmei; Mozaffarian, Dariush; Papoutsakis, Constantina; Syvänen, Ann-Christine; Uitterlinden, André G; Viikari, Jorma; Groves, Christopher J; Hofman, Albert; Lind, Lars; McCarthy, Mark I; Mikkilä, Vera; Mukamal, Kenneth; Franco, Oscar H; Borecki, Ingrid B; Cupples, L Adrienne; Dedoussis, George V; Ferrucci, Luigi; Hu, Frank B; Ingelsson, Erik; Kähönen, Mika; Kao, W H Linda; Kritchevsky, Stephen B; Orho-Melander, Marju; Prokopenko, Inga; Rotter, Jerome I; Siscovick, David S; Witteman, Jacqueline C M; Franks, Paul W; Meigs, James B; McKeown, Nicola M; Nettleton, Jennifer A

    2013-03-01

    Favorable associations between magnesium intake and glycemic traits, such as fasting glucose and insulin, are observed in observational and clinical studies, but whether genetic variation affects these associations is largely unknown. We hypothesized that single nucleotide polymorphisms (SNPs) associated with either glycemic traits or magnesium metabolism affect the association between magnesium intake and fasting glucose and insulin. Fifteen studies from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) Consortium provided data from up to 52,684 participants of European descent without known diabetes. In fixed-effects meta-analyses, we quantified 1) cross-sectional associations of dietary magnesium intake with fasting glucose (mmol/L) and insulin (ln-pmol/L) and 2) interactions between magnesium intake and SNPs related to fasting glucose (16 SNPs), insulin (2 SNPs), or magnesium (8 SNPs) on fasting glucose and insulin. After adjustment for age, sex, energy intake, BMI, and behavioral risk factors, magnesium (per 50-mg/d increment) was inversely associated with fasting glucose [β = -0.009 mmol/L (95% CI: -0.013, -0.005), P magnesium-related SNP or interaction between any SNP and magnesium reached significance after correction for multiple testing. However, rs2274924 in magnesium transporter-encoding TRPM6 showed a nominal association (uncorrected P = 0.03) with glucose, and rs11558471 in SLC30A8 and rs3740393 near CNNM2 showed a nominal interaction (uncorrected, both P = 0.02) with magnesium on glucose. Consistent with other studies, a higher magnesium intake was associated with lower fasting glucose and insulin. Nominal evidence of TRPM6 influence and magnesium interaction with select loci suggests that further investigation is warranted.

  7. Linear shaped charge

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, David; Stofleth, Jerome H.; Saul, Venner W.

    2017-07-11

    Linear shaped charges are described herein. In a general embodiment, the linear shaped charge has an explosive with an elongated arrowhead-shaped profile. The linear shaped charge also has and an elongated v-shaped liner that is inset into a recess of the explosive. Another linear shaped charge includes an explosive that is shaped as a star-shaped prism. Liners are inset into crevices of the explosive, where the explosive acts as a tamper.

  8. Aggregator-Based Interactive Charging Management System for Electric Vehicle Charging

    Directory of Open Access Journals (Sweden)

    Mingchao Xia

    2016-03-01

    Full Text Available With the ongoing large-scale implementation of electric vehicles (EVs, the exploration of a more flexible approach to maintain fair interaction between EVs and the power grid is urgently required. This paper presents an aggregator-based interactive charging management scheme adopting interruptible load (IL pricing, in which the EV aggregator will respond to the load control command of the grid in an EV interactive mode. Charging managements are carried out according to battery state-of-charge and the EV departure time in EV charging stations. A power-altering charging (PAC control method is proposed to dispatch the EVs charging fairly in a station and guarantee EV owners’ preferences. The method does not require classical iterative procedures or heavy computations; furthermore, it is beneficial for EVs to depart earlier than expected for reasons beyond keeping homeostatic charging. The proposed scheme, which is tested to charge individual EVs well according to its preference, was implemented as part of an “EV Beijing” project. The proposed management scheme provides new insight into EV charging strategy and provides another choice to EV users.

  9. Electrodynamics of Radiating Charges

    Directory of Open Access Journals (Sweden)

    Øyvind Grøn

    2012-01-01

    Full Text Available The theory of electrodynamics of radiating charges is reviewed with special emphasis on the role of the Schott energy for the conservation of energy for a charge and its electromagnetic field. It is made clear that the existence of radiation from a charge is not invariant against a transformation between two reference frames that has an accelerated motion relative to each other. The questions whether the existence of radiation from a uniformly accelerated charge with vanishing radiation reaction force is in conflict with the principle of equivalence and whether a freely falling charge radiates are reviewed. It is shown that the resolution of an electromagnetic “perpetuum mobile paradox” associated with a charge moving geodetically along a circular path in the Schwarzschild spacetime requires the so-called tail terms in the equation of motion of a charged particle.

  10. Rovibrationally selected ion-molecule collision study using the molecular beam vacuum ultraviolet laser pulsed field ionization-photoion method: charge transfer reaction of N2(+)(X 2Σg+; v+ = 0-2; N+ = 0-9) + Ar.

    Science.gov (United States)

    Chang, Yih Chung; Xu, Yuntao; Lu, Zhou; Xu, Hong; Ng, C Y

    2012-09-14

    We have developed an ion-molecule reaction apparatus for state-selected absolute total cross section measurements by implementing a high-resolution molecular beam vacuum ultraviolet (VUV) laser pulsed field ionization-photoion (PFI-PI) ion source to a double-quadrupole double-octopole ion-guide mass spectrometer. Using the total cross section measurement of the state-selected N(2)(+)(v(+), N(+)) + Ar charge transfer (CT) reaction as an example, we describe in detail the design of the VUV laser PFI-PI ion source used, which has made possible the preparation of reactant N(2)(+)(X (2)Σ(g)(+), v(+) = 0-2, N(+) = 0-9) PFI-PIs with high quantum state purity, high intensity, and high kinetic energy resolution. The PFI-PIs and prompt ions produced in the ion source are shown to have different kinetic energies, allowing the clean rejection of prompt ions from the PFI-PI beam by applying a retarding potential barrier upstream of the PFI-PI source. By optimizing the width and amplitude of the pulsed electric fields employed to the VUV-PFI-PI source, we show that the reactant N(2)(+) PFI-PI beam can be formed with a laboratory kinetic energy resolution of ΔE(lab) = ± 50 meV. As a result, the total cross section measurement can be conducted at center-of-mass kinetic energies (E(cm)'s) down to thermal energies. Absolute total rovibrationally selected cross sections σ(v(+) = 0-2, N(+) = 0-9) for the N(2)(+)(X (2)Σ(g)(+); v(+) = 0-2, N(+) = 0-9) + Ar CT reaction have been measured in the E(cm) range of 0.04-10.0 eV, revealing strong vibrational enhancements and E(cm)-dependencies of σ(v(+) = 0-2, N(+) = 0-9). The thermochemical threshold at E(cm) = 0.179 eV for the formation of Ar(+) from N(2)(+)(X; v(+) = 0, N(+)) + Ar was observed by the measured σ(v(+) = 0), confirming the narrow ΔE(cm) spread achieved in the present study. The σ(v(+) = 0-2; N(+)) values obtained here are compared with previous experimental and theoretical results. The theoretical predictions

  11. The absence of P2X7 receptors (P2rx7) on non-haematopoietic cells leads to selective alteration in mood-related behaviour with dysregulated gene expression and stress reactivity in mice.

    Science.gov (United States)

    Csölle, Cecilia; Andó, Rómeó D; Kittel, Ágnes; Gölöncsér, Flóra; Baranyi, Mária; Soproni, Krisztina; Zelena, Dóra; Haller, József; Németh, Tamás; Mócsai, Attila; Sperlágh, Beáta

    2013-02-01

    The purpose of this study was to explore how genetic deletion and pharmacological antagonism of the P2X7 receptor (P2rx7) alter mood-related behaviour, gene expression and stress reactivity in the brain. The forced swim test (FST), tail suspension test (TST) and amphetamine-induced hyperlocomotion (AH) tests were used in wild-type (P2rx7(+/+)) and P2rx7-deficient (P2rx7(-/-)) mice. Biogenic amine levels were analysed in the amygdala and striatum, adrenocorticotropic hormone (ACTH) and corticosterone levels were measured in the plasma and pituitary after restraint stress. Chimeric mice were generated by bone marrow transplantation. A whole genome microarray analysis with real-time polymerase chain reaction validation was performed on the amygdala. In the absence of P2rx7s decreased behavioural despair in the FST, reduced immobility in the TST and attenuated amphetamine-induced hyperactivity were detected. Basal norepinephrine levels were elevated in the amygdala, whereas stress-induced ACTH and corticosterone responses were alleviated in P2rx7(-/-) mice. Sub-acute treatment with the selective P2rx7 antagonist, Brilliant Blue G, reproduced the effect of genetic deletion in the TST and AH test in P2rx7(+/+) but not P2rx7(-/-) mice. No change in behavioural phenotype was observed in chimeras lacking the P2rx7 in their haematopoietic compartment. Whole genome microarray analysis indicated a widespread up- and down-regulation of genes crucial for synaptic function and neuroplasticity by genetic deletion. Here, we present evidence that the absence of P2rx7s on non-haematopoietic cells leads to a mood-stabilizing phenotype in several behavioural models and suggest a therapeutic potential of P2rx7 antagonists for the treatment of mood disorders.

  12. Surface Charging and Points of Zero Charge

    CERN Document Server

    Kosmulski, Marek

    2009-01-01

    Presents Points of Zero Charge data on well-defined specimen of materials sorted by trademark, manufacturer, and location. This text emphasizes the comparison between particular results obtained for different portions of the same or very similar material and synthesizes the information published in research reports over the past few decades

  13. Rain Drop Charge Sensor

    Science.gov (United States)

    S, Sreekanth T.

    begin{center} Large Large Rain Drop Charge Sensor Sreekanth T S*, Suby Symon*, G. Mohan Kumar (1) , S. Murali Das (2) *Atmospheric Sciences Division, Centre for Earth Science Studies, Thiruvananthapuram 695011 (1) D-330, Swathi Nagar, West Fort, Thiruvananthapuram 695023 (2) Kavyam, Manacaud, Thiruvananthapuram 695009 begin{center} ABSTRACT To study the inter-relations with precipitation electricity and precipitation microphysical parameters a rain drop charge sensor was designed and developed at CESS Electronics & Instrumentation Laboratory. Simultaneous measurement of electric charge and fall speed of rain drops could be done using this charge sensor. A cylindrical metal tube (sensor tube) of 30 cm length is placed inside another thick metal cover opened at top and bottom for electromagnetic shielding. Mouth of the sensor tube is exposed and bottom part is covered with metal net in the shielding cover. The instrument is designed in such a way that rain drops can pass only through unhindered inside the sensor tube. When electrically charged rain drops pass through the sensor tube, it is charged to the same magnitude of drop charge but with opposite polarity. The sensor tube is electrically connected the inverted input of a current to voltage converter operational amplifier using op-amp AD549. Since the sensor is electrically connected to the virtual ground of the op-amp, the charge flows to the ground and the generated current is converted to amplified voltage. This output voltage is recorded using a high frequency (1kHz) voltage recorder. From the recorded pulse, charge magnitude, polarity and fall speed of rain drop are calculated. From the fall speed drop diameter also can be calculated. The prototype is now under test running at CESS campus. As the magnitude of charge in rain drops is an indication of accumulated charge in clouds in lightning, this instrument has potential application in the field of risk and disaster management. By knowing the charge

  14. Induced Charge Capacitive Deionization

    CERN Document Server

    Rubin, S; Biesheuvel, P M; Bercovici, M

    2016-01-01

    We demonstrate the phenomenon of induced-charge capacitive deionization (ICCDI) that occurs around a porous and conducting particle immersed in an electrolyte, under the action of an external electrostatic field. The external electric field induces an electric dipole in the porous particle, leading to capacitive charging of its volume by both cations and anions at opposite poles. This regime is characterized both by a large RC charging time and a small electrochemical charge relaxation time, which leads to rapid and significant deionization of ionic species from a volume which is on the scale of the particle. We show by theory and experiment that the transient response around a cylindrical particle results in spatially non-uniform charging and non-steady growth of depletion regions which emerge around the particle's poles. Potentially, ICCDI can be useful in applications where fast concentration changes of ionic species are required over large volumes.

  15. The effect of charge on the release kinetics from polysaccharide–nanoclay composites

    Energy Technology Data Exchange (ETDEWEB)

    Buffa, Stefano Del; Grifoni, Emanuele; Ridi, Francesca, E-mail: francesca.ridi@unifi.it; Baglioni, Piero, E-mail: piero.baglioni@unifi.it [University of Florence, Department of Chemistry “Ugo Schiff” and CSGI (Italy)

    2015-03-15

    The objective of this study was to integrate inorganic halloysite nanotubes (HNT) with chitosan and hyaluronic acid to obtain hybrid nanocomposites with opposing charges and to investigate their potential in the controlled release of drug model probes. Two oppositely charged polysaccharides, chitosan and hyaluronic acid, were selected for their biocompatibility and their importance in biomedical applications. The high surface area and the hollow nanometric-sized lumen of HNT allowed for the efficient loading of rhodamine 110 and carboxyfluorescein, used as models for oppositely charged drugs. In the case of chitosan, the preparation of the nanocomposite was carried out exploiting the electrostatic interaction between the polymer and HNT in water, while with hyaluronic acid, a covalent functionalization strategy was employed to couple the polymer with the clay. Nanocomposites were characterized with thermal, microscopic, and spectroscopic techniques, and the release kinetics of the model compounds was assessed by fluorescence measurements. The release curves were fitted with a model able to account for the desorption process from the external and the internal halloysite surfaces. The results show that both polymeric coatings alter the release of the probes, indicating a key role of both charge and coating composition on the initial and final amount of released dye, as well as on the rate of the desorption process.

  16. The effect of charge on the release kinetics from polysaccharide-nanoclay composites

    Science.gov (United States)

    Del Buffa, Stefano; Grifoni, Emanuele; Ridi, Francesca; Baglioni, Piero

    2015-03-01

    The objective of this study was to integrate inorganic halloysite nanotubes (HNT) with chitosan and hyaluronic acid to obtain hybrid nanocomposites with opposing charges and to investigate their potential in the controlled release of drug model probes. Two oppositely charged polysaccharides, chitosan and hyaluronic acid, were selected for their biocompatibility and their importance in biomedical applications. The high surface area and the hollow nanometric-sized lumen of HNT allowed for the efficient loading of rhodamine 110 and carboxyfluorescein, used as models for oppositely charged drugs. In the case of chitosan, the preparation of the nanocomposite was carried out exploiting the electrostatic interaction between the polymer and HNT in water, while with hyaluronic acid, a covalent functionalization strategy was employed to couple the polymer with the clay. Nanocomposites were characterized with thermal, microscopic, and spectroscopic techniques, and the release kinetics of the model compounds was assessed by fluorescence measurements. The release curves were fitted with a model able to account for the desorption process from the external and the internal halloysite surfaces. The results show that both polymeric coatings alter the release of the probes, indicating a key role of both charge and coating composition on the initial and final amount of released dye, as well as on the rate of the desorption process.

  17. High temperature charge amplifier for geothermal applications

    Science.gov (United States)

    Lindblom, Scott C.; Maldonado, Frank J.; Henfling, Joseph A.

    2015-12-08

    An amplifier circuit in a multi-chip module includes a charge to voltage converter circuit, a voltage amplifier a low pass filter and a voltage to current converter. The charge to voltage converter receives a signal representing an electrical charge and generates a voltage signal proportional to the input signal. The voltage amplifier receives the voltage signal from the charge to voltage converter, then amplifies the voltage signal by the gain factor to output an amplified voltage signal. The lowpass filter passes low frequency components of the amplified voltage signal and attenuates frequency components greater than a cutoff frequency. The voltage to current converter receives the output signal of the lowpass filter and converts the output signal to a current output signal; wherein an amplifier circuit output is selectable between the output signal of the lowpass filter and the current output signal.

  18. Spacecraft dielectric material properties and spacecraft charging

    Science.gov (United States)

    Frederickson, A. R.; Wall, J. A.; Cotts, D. B.; Bouquet, F. L.

    1986-01-01

    The physics of spacecraft charging is reviewed, and criteria for selecting and testing semiinsulating polymers (SIPs) to avoid charging are discussed and illustrated. Chapters are devoted to the required properties of dielectric materials, the charging process, discharge-pulse phenomena, design for minimum pulse size, design to prevent pulses, conduction in polymers, evaluation of SIPs that might prevent spacecraft charging, and the general response of dielectrics to space radiation. SIPs characterized include polyimides, fluorocarbons, thermoplastic polyesters, poly(alkanes), vinyl polymers and acrylates, polymers containing phthalocyanine, polyacene quinones, coordination polymers containing metal ions, conjugated-backbone polymers, and 'metallic' conducting polymers. Tables summarizing the results of SIP radiation tests (such as those performed for the NASA Galileo Project) are included.

  19. An improved charge pump with suppressed charge sharing effect

    Directory of Open Access Journals (Sweden)

    Na Bai

    2013-09-01

    Full Text Available A differential charge pump with reduced charge sharing effect is presented. The current-steering topology is adopted for fast switching. A replica charge pump is added to provide a current path for the complementary branch of the master charge pump in the current switching. Through the replica charge pump, the voltage at the complementary node of the master charge pump keeps stable during switching, and the dynamic charge sharing effect is avoided. Apply the charge pump to a 4.8 GHz band integer-N PLL, the measured reference spur is -49.7dBc with a 4-MHz reference frequency.

  20. Surface charge mapping with a nanopipette.

    Science.gov (United States)

    McKelvey, Kim; Kinnear, Sophie L; Perry, David; Momotenko, Dmitry; Unwin, Patrick R

    2014-10-01

    Nanopipettes are emerging as simple but powerful tools for probing chemistry at the nanoscale. In this contribution the use of nanopipettes for simultaneous surface charge mapping and topographical imaging is demonstrated, using a scanning ion conductance microscopy (SICM) format. When a nanopipette is positioned close to a surface in electrolyte solution, the direct ion current (DC), driven by an applied bias between a quasi-reference counter electrode (QRCE) in the nanopipette and a second QRCE in the bulk solution, is sensitive to surface charge. The charge sensitivity arises because the diffuse double layers at the nanopipette and the surface interact, creating a perm-selective region which becomes increasingly significant at low ionic strengths (10 mM 1:1 aqueous electrolyte herein). This leads to a polarity-dependent ion current and surface-induced rectification as the bias is varied. Using distance-modulated SICM, which induces an alternating ion current component (AC) by periodically modulating the distance between the nanopipette and the surface, the effect of surface charge on the DC and AC is explored and rationalized. The impact of surface charge on the AC phase (with respect to the driving sinusoidal signal) is highlighted in particular; this quantity shows a shift that is highly sensitive to interfacial charge and provides the basis for visualizing charge simultaneously with topography. The studies herein highlight the use of nanopipettes for functional imaging with applications from cell biology to materials characterization where understanding surface charge is of key importance. They also provide a framework for the design of SICM experiments, which may be convoluted by topographical and surface charge effects, especially for small nanopipettes.

  1. Nonradiative charge transfer in collisions of protons with rubidium atoms

    Institute of Scientific and Technical Information of China (English)

    Yan Ling-Ling; Qu Yi-Zhi; Liu Chun-Hua; Zhang Yu; Wang Jian-Guo; Buenker Robert J

    2012-01-01

    The nonradiative charge-transfer cross sections for protons colliding with Rb(5s) atoms are calculated by using the quantum-mechanical molecularorbital close-coupling method in an energy range of 10-3 keV 10 keV.The total and state-selective charge-transfer cross sections are in good agreement with the experimental data in the relatively low energy region.The importance of rotational coupling for chargetransfer process is stressed.Compared with the radiative charge-transfer process,nonradiative charge transfer is a dominant mechanism at energies above 15 eV.The resonance structures of state-selective charge-transfer cross sections arising from the competition among channels are analysed in detail.The radiative and nonradiative charge-transfer rate coefficients from low to high temperature are presented.

  2. Space-Charge Effect

    CERN Document Server

    Chauvin, N

    2013-01-01

    First, this chapter introduces the expressions for the electric and magnetic space-charge internal fields and forces induced by high-intensity beams. Then, the root-mean-square equation with space charge is derived and discussed. In the third section, the one-dimensional Child-Langmuir law, which gives the maximum current density that can be extracted from an ion source, is exposed. Space-charge compensation can occur in the low-energy beam transport lines (located after the ion source). This phenomenon, which counteracts the spacecharge defocusing effect, is explained and its main parameters are presented. The fifth section presents an overview of the principal methods to perform beam dynamics numerical simulations. An example of a particles-in-cells code, SolMaxP, which takes into account space-charge compensation, is given. Finally, beam dynamics simulation results obtained with this code in the case of the IFMIF injector are presented.

  3. Water Quality Protection Charges

    Data.gov (United States)

    Montgomery County of Maryland — The Water Quality Protection Charge (WQPC) is a line item on your property tax bill. WQPC funds many of the County's clean water initiatives including: • Restoration...

  4. EV Charging Infrastructure Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Karner, Donald [Electric Transportation Inc., Rogers, AR (United States); Garetson, Thomas [Electric Transportation Inc., Rogers, AR (United States); Francfort, Jim [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-08-01

    As highlighted in the U.S. Department of Energy’s EV Everywhere Grand Challenge, vehicle technology is advancing toward an objective to “… produce plug-in electric vehicles that are as affordable and convenient for the average American family as today’s gasoline-powered vehicles …” [1] by developing more efficient drivetrains, greater battery energy storage per dollar, and lighter-weight vehicle components and construction. With this technology advancement and improved vehicle performance, the objective for charging infrastructure is to promote vehicle adoption and maximize the number of electric miles driven. The EV Everywhere Charging Infrastructure Roadmap (hereafter referred to as Roadmap) looks forward and assumes that the technical challenges and vehicle performance improvements set forth in the EV Everywhere Grand Challenge will be met. The Roadmap identifies and prioritizes deployment of charging infrastructure in support of this charging infrastructure objective for the EV Everywhere Grand Challenge

  5. Primitive Virtual Negative Charge

    CERN Document Server

    Kim, Kiyoung

    2008-01-01

    Physical fields, such as gravity and electromagnetic field, are interpreted as results from rearrangement of vacuum particles to get the equilibrium of net charge density and net mass density in 4-dimensional complex space. Then, both fields should interact to each other in that physical interaction is considered as a field-to-field interaction. Hence, Mass-Charge interaction is introduced with primitive-virtual negative charge defined for the mass. With the concept of Mass-Charge interaction electric equilibrium of the earth is discussed, especially about the electric field and magnetic field of the earth. For unsettled phenomena related with the earth's gravity, such as antigravity phenomenon, gravity anomalies during the solar eclipses, the connection between geomagnetic storms and earthquakes, etc., possible explanations are discussed.

  6. The London Congestion Charge

    National Research Council Canada - National Science Library

    Leape, Jonathan

    2006-01-01

    .... Traffic congestion has declined substantially, and the program is largely popular. This article describes the origins of the London congestion charge, how it overcame practical and theoretical difficulties, and what effects it has had...

  7. Electrically charged targets

    Science.gov (United States)

    Goodman, Ronald K.; Hunt, Angus L.

    1984-01-01

    Electrically chargeable laser targets and method for forming such charged targets in order to improve their guidance along a predetermined desired trajectory. This is accomplished by the incorporation of a small amount of an additive to the target material which will increase the electrical conductivity thereof, and thereby enhance the charge placed upon the target material for guidance thereof by electrostatic or magnetic steering mechanisms, without adversely affecting the target when illuminated by laser energy.

  8. Charge-sensitive amplifier

    Directory of Open Access Journals (Sweden)

    Startsev V. I.

    2008-02-01

    Full Text Available The authors consider design and circuit design techniques of reduction of the influence of the pyroelectric effect on operation of the charge sensitive amplifiers. The presented experimental results confirm the validity of the measures taken to reduce the impact of pyroelectric currents. Pyroelectric currents are caused by the influence of the temperature gradient on the piezoelectric sensor and on the output voltage of charge sensitive amplifiers.

  9. Electric Vehicle Charging Modeling

    OpenAIRE

    Grahn, Pia

    2014-01-01

    With an electrified passenger transportation fleet, carbon dioxide emissions could be reduced significantly depending on the electric power production mix. Increased electric power consumption due to electric vehicle charging demands of electric vehicle fleets may be met by increased amount of renewable power production in the electrical systems. With electric vehicle fleets in the transportation system there is a need for establishing an electric vehicle charging infrastructure that distribu...

  10. Charged Higgs Boson Searches

    CERN Document Server

    The ATLAS collaboration

    2009-01-01

    The discovery of a charged Higgs boson would be tangible proof of physics beyond the Standard Model. This note presents the ATLAS potential for discovering a charged Higgs boson, utilizing five different final states of the signal arising from the three dominating fermionic decay modes of the charged Higgs boson. The search covers the region below the top quark mass, taking into account the present experimental constraints, the transition region with a charged Higgs boson mass of the order of the top quark mass, and the high-mass region with a charged Higgs boson mass up to 600 GeV. All studies are performed with a realistic simulation of the detector response including all three trigger levels and taking into account all dominant systematic uncertainties. Results are given in terms of discovery and exclusion contours for each channel individually and for all channels combined, showing that the ATLAS experiment is capable of detecting the charged Higgs boson in a significant fraction of the (tan beta , mH+-) ...

  11. [Altered states of consciousness].

    Science.gov (United States)

    Gora, E P

    2005-01-01

    The review of modern ideas concerning the altered states of consciousness is presented in this article. Various methods of entry into the altered states of consciousness are looked over. It is shown that the altered states of consciousness are insufficiently known, but important aspects of human being existence. The role of investigation of the altered states of consciousness for the creation of integrative scientific conception base is discussed.

  12. Selective Alteration of Steranes in Heavy Biodegraded Oils from Dongying Sag%东营凹陷生物降解稠油甾烷分子的选择蚀变

    Institute of Scientific and Technical Information of China (English)

    陈中红; Moldowan J M; 刘昭茜

    2012-01-01

    The alkane and aromatic fraction of eleven biodegraded oils and five non-biodegraded oils from the Dongying Depression,Bohai Bay Basin,Eastern China were analyzed by GC-MS to investigate the effects of biodegradation and thermal maturation on the distributions of steranes.The results indicate that the biodegradation and depletion of steranes emerged in the heavily biodegraded oils(scale≥6).The oil samples show an increase in the C29 sterane C2920S/(20S+20R) and C29ββ/(ββ+αα) thermal maturity parameters in the heavily biodegraded oils,indicating this level of biodegradation(scale≥6) can alter the two maturity parameters.The selective depletion of C27-C29 steranes follows the order ααα 20Rαββ 20Rαββ 20S≥ααα 20S and C27C29C28,and the diasteranes and C20-C21 steranes were much more resistant to biodegradation than regular C27-C29 steranes.%为分析生物降解原油中甾烷生物标志物分子发生选择性蚀变的先后顺序及生物降解作用对甾烷分子成熟度参数的影响,在渤海湾盆地东营凹陷广饶潜山油藏选择了发生不同程度生物降解作用的原油,利用色谱质谱(GC-MS)仪对其中甾烷进行了定量测试分析和对比。结果发现在生物降解过程中,不同级别的生物降解作用对甾烷具有不同程度的影响:6级以下的生物降解作用对甾烷的降解能力有限,甾烷及其相关化合物比值没有可以识别的改变;6级以上的严重生物降解作用会对甾烷生物标志物的相关参数产生显著的影响。在严重生物降解原油中(级别≥6):甾烷系列被降解和蚀耗的先后顺序为,ααα20R〉αββ20R〉αββ20S≥ααα20S,C27〉C29〉C28,规则甾烷优先于重排甾烷发生降解,C27,C28,C29甾烷优先于C20,C21甾烷发生降解;甾烷生物标志物分子参数C2920S/(20S+20R),C29ββ/(ββ+αα)会发生显著升高,不能真实反映成熟度大小。研究结果为正确评价生物降解原油的成

  13. Adsorption of charged protein residues on an inorganic nanosheet: Computer simulation of LDH interaction with ion channel

    Science.gov (United States)

    Tsukanov, Alexey A.; Psakhie, Sergey G.

    2016-08-01

    Quasi-two-dimensional and hybrid nanomaterials based on layered double hydroxides (LDH), cationic clays, layered oxyhydroxides and hydroxides of metals possess large specific surface area and strong electrostatic properties with permanent or pH-dependent electric charge. Such nanomaterials may impact cellular electrostatics, changing the ion balance, pH and membrane potential. Selective ion adsorption/exchange may alter the transmembrane electrochemical gradient, disrupting potential-dependent cellular processes. Cellular proteins as a rule have charged residues which can be effectively adsorbed on the surface of layered hydroxide based nanomaterials. The aim of this study is to attempt to shed some light on the possibility and mechanisms of protein "adhesion" an LDH nanosheet and to propose a new direction in anticancer medicine, based on physical impact and strong electrostatics. An unbiased molecular dynamics simulation was performed and the combined process free energy estimation (COPFEE) approach was used.

  14. Multipole Expansions of Aggregate Charge: How Far to Go?

    CERN Document Server

    Matthews, Lorin S; Hyde, Truell W

    2015-01-01

    Aggregates immersed in a plasma or radiative environment will have charge distributed over their extended surface. Previous studies have modeled the aggregate charge using the monopole and dipole terms of a multipole expansion, with results indicating that the dipole-dipole interactions play an important role in increasing the aggregation rate and altering the morphology of the resultant aggregates. This study examines the effect that including the quadrupole terms has on the dynamics of aggregates interacting with each other and the confining electric fields in laboratory experiments. Results are compared to modeling aggregates as a collection of point charges located at the center of each spherical monomer comprising the aggregate.

  15. Electric vehicle battery charging controller

    DEFF Research Database (Denmark)

    2016-01-01

    to a battery management system in the electric vehicle to charge a battery therein, a first communication unit for receiving a charging message via a communication network, and a control unit for controlling a charging current provided from the charge source to the electric vehicle, the controlling at least...

  16. Charge transport in organic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ortmann, Frank

    2009-07-01

    The understanding of charge transport is one of the central goals in the research on semiconducting crystals. For organic crystals this is particularly complicated due to the strength of the electron-phonon interaction which requires the description of a seamless transition between the limiting cases of a coherent band-transport mechanism and incoherent hopping. In this thesis, charge transport phenomena in organic crystals are studied by theoretical means. A theory for charge transport in organic crystals is developed which covers the whole temperature range from low T, where it reproduces an expression from the Boltzmann equation for band transport, via elevated T, where it generalizes Holstein's small-polaron theory to finite bandwidths, up to high T, for which a temperature dependence equal to Marcus' electron-transfer theory is obtained. Thereby, coherent band transport and thermally induced hopping are treated on equal footing while simultaneously treating the electron-phonon interaction non-perturbatively. By avoiding the approximation of narrow polaron bands the theory allows for the description of large and small polarons and serves as a starting point for computational studies. The theoretical description is completed by using ab initio material parameters for the selected crystals under study. These material parameters are taken from density functional theory calculations for durene, naphthalene, and guanine crystals. Besides the analysis of the transport mechanism, special focus is put on the study of the relationship between mobility anisotropy and structure of the crystals. This study is supported by a 3D-visualization method for the transport channels in such crystals which has been derived in this thesis. (orig.)

  17. Holographic charge density waves

    CERN Document Server

    Donos, Aristomenis

    2013-01-01

    We show that strongly coupled holographic matter at finite charge density can exhibit charge density wave phases which spontaneously break translation invariance while preserving time-reversal and parity invariance. We show that such phases are possible within Einstein-Maxwell-dilaton theory in general spacetime dimensions. We also discuss related spatially modulated phases when there is an additional coupling to a second vector field, possibly with non-zero mass. We discuss how these constructions, and others, should be associated with novel spatially modulated ground states.

  18. Holographic charge density waves

    Science.gov (United States)

    Donos, Aristomenis; Gauntlett, Jerome P.

    2013-06-01

    We show that strongly coupled holographic matter at finite charge density can exhibit charge density wave phases which spontaneously break translation invariance while preserving time-reversal and parity invariance. We show that such phases are possible within Einstein-Maxwell-dilaton theory in general spacetime dimensions. We also discuss related spatially modulated phases when there is an additional coupling to a second vector field, possibly with nonzero mass. We discuss how these constructions, and others, should be associated with novel spatially modulated ground states.

  19. Charges for linearized gravity

    CERN Document Server

    Aksteiner, Steffen

    2013-01-01

    Maxwell test fields as well as solutions of linearized gravity on the Kerr exterior admit non-radiating modes, i.e. non-trivial time-independent solutions. These are closely related to conserved charges. In this paper we discuss the non-radiating modes for linearized gravity, which may be seen to correspond to the Poincare Lie-algebra. The 2-dimensional isometry group of Kerr corresponds to a 2-parameter family of gauge-invariant non-radiating modes representing infinitesimal perturbations of mass and azimuthal angular momentum. We calculate the linearized mass charge in terms of linearized Newman-Penrose scalars.

  20. Developing waste water charges and water extraction charges into an all-embracing water utilisation charge; Weiterentwicklung von Abwasserabgabe und Wasserentnahmeentgelten zu einer umfassenden Wassernutzungsabgabe

    Energy Technology Data Exchange (ETDEWEB)

    Gawel, Erik; Koeck, Wolfgang; Kern, Katharina; Moeckel, Stefan [Helmholtz-Zentrum fuer Umweltforschung GmbH - UFZ, Leipzig (Germany); Hollaender, Robert; Faelsch, Marcel; Voelkner, Thomas [Leipzig Univ. (Germany). Inst. fuer Infrastruktur und Ressourcenmanagement

    2011-10-15

    The use of economic instruments in water protection policy in the form of wastewater charges under German federal law and the various water extraction charges levied by individual German federal states has a long history in Germany. The critical accompaniment of these instruments in economics and politics is equally as long. A comprehensive, more recent analysis of experiences with the instruments wastewater charges and water extraction charges in Germany has not yet been conducted. In particular Art. 9 of the EU's Water Framework Directive that requires among other things to take into account the basic cost recovery principle for water services (including environmental and resource costs) gives reason to put these instruments to the test: To what extent do wastewater charges and water extraction charges contribute to the new legally-formulated goals of the European Community in water quality policy? Can effectiveness and efficiency be improved through a change of design and are they even a model for an extension of charge requirements on further water uses? The WFD also offers cause here to think about the extent to which the application of economic control mechanisms should be expanded in terms of claims on aquatic ecosystem services. In a reform and modernisation of these charges as well as in the introduction of new charges, the specifications of European and federal law as well as steering aspects from economics and public economics and altered basic conditions in water management must be considered. Given this background, in an interdisciplinary analysis the report examines the efficiency and reform options of existing charges as well as the introduction of new water use charges in the fields of agriculture, shipping and hydro-power. (orig.)

  1. Study on molecular modelling of the selectivity of catalysts for heavy petroleum fractions hydrocracking; Etude sur molecule modele des parametres regissant la selectivite des catalyseurs d'hydrocraquage des charges lourdes

    Energy Technology Data Exchange (ETDEWEB)

    Leite, L.

    2000-10-19

    Hydrocracking is a catalytic petroleum refining process that is commonly applied to upgrade the heavier fractions obtained from the distillation of crude oils. Nowadays the European demand for good quality middle distillates (kerosene and gas-oil) is high and one important goal for the refining is to transform selectively feedstocks into middle distillates. To understand how this transformation occurs, studies on model compounds have been investigated. Numerous studies have been devoted to paraffin hydrocracking. However theses molecules do not fully represent heavy petroleum fraction. Taking into account that the trend in the future will be to treat heavier feedstocks containing a large quantity of PNA (Polynuclear Aromatic hydrocarbons), the understanding of their transformation under hydrocracking conditions is a key point. In this study, we studied hydrocracking of phenanthrene over platinum on acid solids catalysts. Our main aim was to compare hydrocracking catalysts in term of catalytic activity and selectivity toward primary products thanks to our model reaction and to correlate these catalytic performances with acid solid properties and especially to rationalize the effects due to the acidity and the porosity of the acid solids. Catalytic experiments emphasised an effect of the porous structure on the selectivities. The acidity of the catalysts seemed to impose the catalytic activity but did not permit to explain the selectivities. This 'effect of the structure' has been clarified with the simulation of intermediate products adsorption and diffusion in the studied structures thanks to a molecular modelling study. Indeed, the selectivities obtained during phenanthrene hydrocracking have been linked up with the intermediate products adsorption energies in the structures. The results of this study permit to propose that the key-step for selectivities determination is the physical desorption of the primary products. (author)

  2. Charged particle beams

    CERN Document Server

    Humphries, Stanley

    2013-01-01

    Detailed enough for a text and sufficiently comprehensive for a reference, this volume addresses topics vital to understanding high-power accelerators and high-brightness-charged particle beams. Subjects include stochastic cooling, high-brightness injectors, and the free electron laser. Humphries provides students with the critical skills necessary for the problem-solving insights unique to collective physics problems. 1990 edition.

  3. The London Congestion Charge

    National Research Council Canada - National Science Library

    Leape, Jonathan

    2006-01-01

    .... In early 2003, London imposed a congestion charge—a daily charge for driving or parking a vehicle on public roads within central London between the hours of 7:00 a.m. and 6:30 p.m. on workdays...

  4. Ion and water transport in charge-modified graphene nanopores

    Institute of Scientific and Technical Information of China (English)

    裘英华; 李堃; 陈伟宇; 司伟; 谭启檐; 陈云飞

    2015-01-01

    Porous graphene has a high mechanical strength and an atomic-layer thickness that makes it a promising material for material separation and biomolecule sensing. Electrostatic interactions between charges in aqueous solutions are a type of strong long-range interaction that may greatly infl uence fl uid transport through nanopores. In this study, molecular dynamic simulations were conducted to investigate ion and water transport through 1.05-nm diameter monolayer graphene nanopores, with their edges charge-modified. Our results indicated that these nanopores are selective to counterions when they are charged. As the charge amount increases, the total ionic currents show an increase–decrease profile while the co-ion currents monotonically decrease. The co-ion rejection can reach 76.5%and 90.2%when the nanopores are negatively and positively charged, respectively. The Cl−ion current increases and reaches a plateau, and the Na+current decreases as the charge amount increases in systems in which Na+ions act as counterions. In addition, charge modification can enhance water transport through nanopores. This is mainly due to the ion selectivity of the nanopores. Notably, positive charges on the pore edges facilitate water transport much more strongly than negative charges.

  5. EDITORIAL: Nanotechnological selection Nanotechnological selection

    Science.gov (United States)

    Demming, Anna

    2013-01-01

    At the nanoscale measures can move from a mass-scale analogue calibration to counters of discrete units. The shift redefines the possible levels of control that can be achieved in a system if adequate selectivity can be imposed. As an example as ionic substances pass through nanoscale pores, the quantity of ions is low enough that the pore can contain either negative or positive ions. Yet precise control over this selectivity still raises difficulties. In this issue researchers address the challenge of how to regulate the ionic selectivity of negative and positive charges with the use of an external charge. The approach may be useful for controlling the behaviour, properties and chemical composition of liquids and has possible technical applications for nanofluidic field effect transistors [1]. Selectivity is a critical advantage in the administration of drugs. Nanoparticles functionalized with targeting moieties can allow delivery of anti-cancer drugs to tumour cells, whilst avoiding healthy cells and hence reducing some of the debilitating side effects of cancer treatments [2]. Researchers in Belarus and the US developed a new theranostic approach—combining therapy and diagnosis—to support the evident benefits of cellular selectivity that can be achieved when nanoparticles are applied in medicine [3]. Their process uses nanobubbles of photothermal vapour, referred to as plasmonic nanobubbles, generated by plasmonic excitations in gold nanoparticles conjugated to diagnosis-specific antibodies. The intracellular plasmonic nanobubbles are controlled by laser fluence so that the response can be tuned in individual living cells. Lower fluence allows non-invasive high-sensitive imaging for diagnosis and higher fluence can disrupt the cellular membrane for treatments. The selective response of carbon nanotubes to different gases has leant them to be used within various different types of sensors, as summarized in a review by researchers at the University of

  6. Ion and water transport in charge-modified graphene nanopores

    CERN Document Server

    Qiu, Yinghua; Chen, Weiyu; Si, Wei; Tan, Qiyan; Chen, Yunfei

    2016-01-01

    Porous graphene has high mechanical strength and atomic layer thickness, which make it a promising material for material separation and biomolecule sensing. Electrostatic interactions between charges in aqueous solution are a kind of strong long-range interaction which may have great influence on the fluid transport through nanopores. Here, molecular dynamics simulations were conducted to investigate ion and water transport through a 1.05-nm-in-diameter monolayer graphene nanopore with its edge charge-modified. From the results, it is found that the nanopores are selective to counterions when they are charged. As the charge amount increases, the total ionic currents show an increase-decrease profile while the co-ion currents monotonously decrease. The co-ions rejection can reach 75% and 90% when the nanopores are negatively and positively charged, respectively. Cl ions current increases and reaches a plateau, and Na+ current decreases with the charge amount in the systems where they act as counterions. Beside...

  7. Electrostatic charging and control of droplets in microfluidic devices.

    Science.gov (United States)

    Zhou, Hongbo; Yao, Shuhuai

    2013-03-07

    Precharged droplets can facilitate manipulation and control of low-volume liquids in droplet-based microfluidics. In this paper, we demonstrate non-contact electrostatic charging of droplets by polarizing a neutral droplet and splitting it into two oppositely charged daughter droplets in a T-junction microchannel. We performed numerical simulation to analyze the non-contact charging process and proposed a new design with a notch at the T-junction in aid of droplet splitting for more efficient charging. We experimentally characterized the induced charge in droplets in microfabricated devices. The experimental results agreed well with the simulation. Finally, we demonstrated highly effective droplet manipulation in a path selection unit appending to the droplet charging. We expect our work could enable precision manipulation of droplets for more complex liquid handling in microfluidics and promote electric-force based manipulation in 'lab-on-a-chip' systems.

  8. Charge and Size Distributions of Electrospray Drops

    Science.gov (United States)

    de Juan L; de la Mora JF

    1997-02-15

    The distributions of charge q and diameter d of drops emitted from electrified liquid cones in the cone-jet mode are investigated with two aerosol instruments. A differential mobility analyzer (DMA, Vienna type) first samples the spray drops, selects those with electrical mobilities within a narrow band, and either measures the associated current or passes them to a second instrument. The drops may also be individually counted optically and sized by sampling them into an aerodynamic size spectrometer (API's Aerosizer). For a given cone-jet, the distribution of charge q for the main electrospray drops is some 2.5 times broader than their distribution of diameters d, with qmax/qmin approximately 4. But mobility-selected drops have relative standard deviations of only 5% for both d and q, showing that the support of the (q, d) distribution is a narrow band centered around a curve q(d). The approximate one-dimensionality of this support region is explained through the mechanism of jet breakup, which is a random process with only one degree of freedom: the wavelength of axial modulation of the jet. The observed near constancy of the charge over volume ratio (q approximately d3) shows that the charge is frozen in the liquid surface at the time scale of the breakup process. The charge over volume ratio of the primary drops varies between 98 and 55% of the ratio of spray current I over liquid flow rate Q, and decreases at increasing Q. I/Q is therefore an unreliable measure of the charge density of these drops.

  9. Optimization of BEV Charging Strategy

    Science.gov (United States)

    Ji, Wei

    This paper presents different approaches to optimize fast charging and workplace charging strategy of battery electric vehicle (BEV) drivers. For the fast charging analysis, a rule-based model was built to simulate BEV charging behavior. Monte Carlo analysis was performed to explore to the potential range of congestion at fast charging stations which could be more than four hours at the most crowded stations. Genetic algorithm was performed to explore the theoretical minimum waiting time at fast charging stations, and it can decrease the waiting time at the most crowded stations to be shorter than one hour. A deterministic approach was proposed as a feasible suggestion that people should consider to take fast charging when the state of charge is approaching 40 miles. This suggestion is hoped to help to minimize potential congestion at fast charging stations. For the workplace charging analysis, scenario analysis was performed to simulate temporal distribution of charging demand under different workplace charging strategies. It was found that if BEV drivers charge as much as possible and as late as possible at workplace, it could increase the utility of solar-generated electricity while relieve grid stress of extra intensive electricity demand at night caused by charging electric vehicles at home.

  10. Development of a Microcontroller-based Battery Charge Controller for an Off-grid Photovoltaic System

    Science.gov (United States)

    Rina, Z. S.; Amin, N. A. M.; Hashim, M. S. M.; Majid, M. S. A.; Rojan, M. A.; Zaman, I.

    2017-08-01

    A development of a microcontroller-based charge controller for a 12V battery has been explained in this paper. The system is designed based on a novel algorithm to couple existing solar photovoltaic (PV) charging and main grid supply charging power source. One of the main purposes of the hybrid charge controller is to supply a continuous charging power source to the battery. Furthermore, the hybrid charge controller was developed to shorten the battery charging time taken. The algorithm is programmed in an Arduino Uno R3 microcontroller that monitors the battery voltage and generates appropriate commands for the charging power source selection. The solar energy is utilized whenever the solar irradiation is high. The main grid supply will be only consumed whenever the solar irradiation is low. This system ensures continuous charging power supply and faster charging of the battery.

  11. 75 FR 77741 - Federal Acquisition Regulation; Limitation on Pass-Through Charges

    Science.gov (United States)

    2010-12-13

    ...-through charges deep into the supply chain. Response: The Councils do not concur with the respondent's... activities with respect to subcontractor sourcing, selection, negotiation, and administration that facilitate...

  12. Measurement of Neutrino Induced, Charged Current, Charged Pion Production

    Energy Technology Data Exchange (ETDEWEB)

    Wilking, Michael Joseph [Univ. of Colorado, Boulder, CO (United States)

    2009-05-01

    Neutrinos are among the least understood particles in the standard model of particle physics. At neutrino energies in the 1 GeV range, neutrino properties are typically determined by observing the outgoing charged lepton produced in a charged current quasi-elastic interactions. The largest charged current background to these measurements comes from charged current pion production interactions, for which there is very little available data.

  13. Perturbatively charged holographic disorder

    CERN Document Server

    O'Keeffe, Daniel K

    2015-01-01

    Within the framework of holography applied to condensed matter physics, we study a model of perturbatively charged disorder in D=4 dimensions. Starting from initially uncharged AdS_4, a randomly fluctuating boundary chemical potential is introduced by turning on a bulk gauge field parameterized by a disorder strength and a characteristic scale k_0. Accounting for gravitational backreaction, we construct an asymptotically AdS solution perturbatively in the disorder strength. The disorder averaged geometry displays unphysical divergences in the deep interior. We explain how to remove these divergences and arrive at a well behaved solution. The disorder averaged DC conductivity is calculated and is found to contain a correction to the AdS result. The correction appears at second order in the disorder strength and scales inversely with k_0. We discuss the extension to a system with a finite initial charge density. The disorder averaged DC conductivity may be calculated by adopting a technique developed for hologr...

  14. Electrically charged curvaton

    CERN Document Server

    D'Onofrio, Michela; Rajantie, Arttu

    2012-01-01

    We consider the possibility that the primordial curvature perturbation was generated through the curvaton mechanism from a scalar field with an electric charge, or precisely the Standard Model U(1) weak hypercharge. This links the dynamics of the very early universe concretely to the Standard Model of particle physics, and because the coupling strength is known, it reduces the number of free parameters in the curvaton model. We show that the model is compatible with CMB observations for Hubble rate $H_* > 10^8 GeV$ and curvaton mass $m > 10^{-2}H_*$. Charge fluctuations generated during inflation are screened by electron-positron pairs, and therefore do not violate observational constraints. The interaction with the gauge field leads to interesting dynamics after inflation, including resonant preheating, with potentially highly non-trivial observational consequences, which should be studied more carefully using numerical field theory simulations.

  15. Charged Lifshitz Black Holes

    OpenAIRE

    Dehghani, M. H.; Pourhasan, R.; Mann, R. B.

    2011-01-01

    We investigate modifications of the Lifshitz black hole solutions due to the presence of Maxwell charge in higher dimensions for arbitrary $z$ and any topology. We find that the behaviour of large black holes is insensitive to the topology of the solutions, whereas for small black holes significant differences emerge. We generalize a relation previously obtained for neutral Lifshitz black branes, and study more generally the thermodynamic relationship between energy, entropy, and chemical pot...

  16. Extremally charged line

    CERN Document Server

    Ryzner, Jiří

    2016-01-01

    We investigate the properties of a static, cylindrically symmetric Majumdar-Papapetrou-type solution of Einstein-Maxwell equations. We locate its singularities, establish its algebraic type, find its asymptotic properties and weak-field limit, study the structure of electrogeodesics, and determine the mass and charge of its sources. We provide an interpretation of the spacetime and discuss the parameter appearing in the metric.

  17. Existence of magnetic charge

    Science.gov (United States)

    Akers, David

    1990-10-01

    A status report is presented on the existence of quarks carrying the Dirac unit of magnetic charge g = (137/2) e. The Paschen-Back effect in dyonium is discussed. From the dyonium model, Akers predicted the existence of a new η meson at 1814 MeV with I G(JPC) = 0+(0-+). Experimental evidence now confirms the existence of the meson resonance.

  18. Oral alterations among chemical dependents

    Directory of Open Access Journals (Sweden)

    Estela Vanessa COLODEL

    2009-03-01

    Full Text Available Introduction: It has been daily observed a significant increase ofchemical dependent individuals, as well as the lack of depth on thisissue in the dentistry area. Nevertheless many times the dentalclinicians are the first professionals to diagnose possible alterations,which appear due to the consumption of tobacco, alcohol and other illicit drugs. Objectives: To make a literature review of oral alterations and to identify them on a specific group of persons, which are addicted to different types of drugs. Material and methods: The clinical history of the selected individuals was added to the answers of a questionnaire,comprising the data of the present research. Results: Besides other minor soft tissue alterations, a high prevalence of caries and periodontal diseases were found in the studied population. Conclusion: It was concluded that the role of the dental clinician is very important to the health rehabilitation of drug addicts, individuals with physical and mental disorders that need specific oral care, which sometimes is neglected.

  19. Distributed charging of electrical assets

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Soumyadip; Phan, Dung; Sharma, Mayank; Wu, Chai Wah; Xiong, Jinjun

    2016-02-16

    The present disclosure relates generally to the field of distributed charging of electrical assets. In various examples, distributed charging of electrical assets may be implemented in the form of systems, methods and/or algorithms.

  20. Banking Bank Charge Debates Continue

    Institute of Scientific and Technical Information of China (English)

    WANG PEI

    2006-01-01

    @@ The saying, "There's no such thing as a free lunch" is one that can be applied to the charges increasingly being imposed on savers by Chinese banks.Ranging from managementfees for small deposit accounts to charges for withdrawals of large amounts of cash, from ATM cross-bank withdrawal charges to annual fees for bank payment cards, charges by banks are becoming a unstoppable trend. But it is not a trend the general public is so keen to accept.

  1. Notch Charge-Coupled Devices

    Science.gov (United States)

    Janesick, James

    1992-01-01

    Notch charge-coupled devices are imaging arrays of photodetectors designed to exhibit high charge-transfer efficiencies necessary for operation in ultra-large array, and less vulnerable to degradation by energetic protons, neutrons, and electrons. Main channel of horizontal register includes deep narrow inner channel (notch). Small packets of charge remain confined to notch. Larger packets spill into rest of channel; transferred in usual way. Degradation of charge-transfer efficiency by energetic particles reduced.

  2. Modular Battery Charge Controller

    Science.gov (United States)

    Button, Robert; Gonzalez, Marcelo

    2009-01-01

    A new approach to masterless, distributed, digital-charge control for batteries requiring charge control has been developed and implemented. This approach is required in battery chemistries that need cell-level charge control for safety and is characterized by the use of one controller per cell, resulting in redundant sensors for critical components, such as voltage, temperature, and current. The charge controllers in a given battery interact in a masterless fashion for the purpose of cell balancing, charge control, and state-of-charge estimation. This makes the battery system invariably fault-tolerant. The solution to the single-fault failure, due to the use of a single charge controller (CC), was solved by implementing one CC per cell and linking them via an isolated communication bus [e.g., controller area network (CAN)] in a masterless fashion so that the failure of one or more CCs will not impact the remaining functional CCs. Each micro-controller-based CC digitizes the cell voltage (V(sub cell)), two cell temperatures, and the voltage across the switch (V); the latter variable is used in conjunction with V(sub cell) to estimate the bypass current for a given bypass resistor. Furthermore, CC1 digitizes the battery current (I1) and battery voltage (V(sub batt) and CC5 digitizes a second battery current (I2). As a result, redundant readings are taken for temperature, battery current, and battery voltage through the summation of the individual cell voltages given that each CC knows the voltage of the other cells. For the purpose of cell balancing, each CC periodically and independently transmits its cell voltage and stores the received cell voltage of the other cells in an array. The position in the array depends on the identifier (ID) of the transmitting CC. After eight cell voltage receptions, the array is checked to see if one or more cells did not transmit. If one or more transmissions are missing, the missing cell(s) is (are) eliminated from cell

  3. Predictions of nuclear charge radii

    Science.gov (United States)

    Bao, M.; Lu, Y.; Zhao, Y. M.; Arima, A.

    2016-12-01

    The nuclear charge radius is a fundamental property of an atomic nucleus. In this article we study the predictive power of empirical relations for experimental nuclear charge radii of neighboring nuclei and predict the unknown charge radii of 1085 nuclei based on the experimental CR2013 database within an uncertainty of 0.03 fm.

  4. Improving Charging-Breeding Simulations with Space-Charge Effects

    Science.gov (United States)

    Bilek, Ryan; Kwiatkowski, Ania; Steinbrügge, René

    2016-09-01

    Rare-isotope-beam facilities use Highly Charged Ions (HCI) for accelerators accelerating heavy ions and to improve measurement precision and resolving power of certain experiments. An Electron Beam Ion Trap (EBIT) is able to create HCI through successive electron impact, charge breeding trapped ions into higher charge states. CBSIM was created to calculate successive charge breeding with an EBIT. It was augmented by transferring it into an object-oriented programming language, including additional elements, improving ion-ion collision factors, and exploring the overlap of the electron beam with the ions. The calculation is enhanced with the effects of residual background gas by computing the space charge due to charge breeding. The program assimilates background species, ionizes and charge breeds them alongside the element being studied, and allows them to interact with the desired species through charge exchange, giving fairer overview of realistic charge breeding. Calculations of charge breeding will be shown for realistic experimental conditions. We reexamined the implementation of ionization energies, cross sections, and ion-ion interactions when charge breeding.

  5. Charge dynamic characteristics in corona-charged polytetrafluoroethylene film electrets

    Institute of Scientific and Technical Information of China (English)

    陈钢进; 肖慧明; 朱春凤

    2004-01-01

    In this work, the charge dynamics characteristics of injection, transport and decay in porous and non-porous polytetrafluoroethylene (PTFE) film electrets were investigated by means of corona charging, isothermal and thermal stimulating surface-potential decay measurements. The results showed that the initial surface potential, whether positively or negatively charging, is much higher in non-porous PTFE than in porous PTFE. For porous film the value of initial sur-face potentials increases with increase of film thickness. Higher charging temperature can remarkably improve charge stability. The charge dynamics are correlated to materials microstructure according to their scanning electron micrographs.For non-porous PTFE films, polarizability change of C-F bonds is the main origin of electret charges; but for porous PTFE film a large number of bulk and interface type traps are expected because of the greater area of interface and higher crys-tallinity.

  6. Charge dynamic characteristics in corona-charged polytetrafluoroethylene film electrets

    Institute of Scientific and Technical Information of China (English)

    陈钢进; 肖慧明; 朱春凤

    2004-01-01

    In this work, the charge dynamics characteristics of injection, transport and decay in porous and non-porous polytetrafluoroethylene (PTFE) film electrets were investigated by means of corona charging, isothermal and thermal stimulating surface-potential decay measurements. The results showed that the initial surface potential, whether positively or negatively charging, is much higher in non-porous PTFE than in porous PTFE. For porous film the value of initial surface potentials increases with increase of film thickness. Higher charging temperature can remarkably improve charge stability. The charge dynamics are correlated to materials microstructure according to their scanning electron micrographs.For non-porous PTFE films, polarizability change of C-F bonds is the main origin of electret charges; but for porous PTFE film a large number of bulk and interface type traps are expected because of the greater area of interface and higher crystallinity.

  7. Charge renormalization in planar and spherical charged lipidic aqueous interfaces.

    Science.gov (United States)

    Bordi, Federico; Cametti, Cesare; Sennato, Simona; Paoli, Beatrice; Marianecci, Carlotta

    2006-03-16

    The charge renormalization in planar and spherical charged lipidic aqueous interfaces has been investigated by means of thermodynamic and electrokinetic measurements. We analyzed the behavior of mixed DOTAP/DOPE monolayers at the air-electrolyte solution interface and DOTAP/DOPE liposomes 100 nm in size dispersed in an aqueous phase of varying ionic strength. For the two systems, we have compared the "effective" surface charge derived from the measurements of surface potential and zeta-potential to the "bare" charge based on the stoichiometry of the lipid mixture investigated. The results confirm that a strong charge renormalization occurs, whose strength depends on the geometry of the mesoscopic system. The dependence of the "effective" charge on the "bare" charge is discussed in light of an analytical approximation based on the Poisson-Boltzmann equation recently proposed.

  8. Charge Stripper Effects on Beam Optics in 180-degree Bending Section of RISP Linac

    CERN Document Server

    Jang, Ji-Ho; Song, Jeong Seog

    2016-01-01

    The RAON, a superconducting linear accelerator for RISP (Rare Isotope Science Project), will use a charge stripper in order to increase the charge states of the heavy ions for effective acceleration in the higher energy part of the linac. The charge stripper affects the beam qualities by scattering when the heavy ions go through the charge stripper. Moreover we have to select and accelerate proper charge states between 77+ and 81+ for uranium beam case in order to satisfy the beam power requirement at an IF (Inflight Fragmentation) target. This work focuses on the beam optics affected by the charge stripper in the 180-dgree bending section.

  9. Sample Preconcentration in Nanochannels with Tunable Surface Charge

    Science.gov (United States)

    Eden, Alexander; McCallum, Christopher; Storey, Brian; Meinhart, Carl; Pennathur, Sumita

    2016-11-01

    We present a novel method for field amplified sample stacking (FASS) and focusing in nanochannels by taking advantage of the nonuniform ion distributions produced by thick electric double layers (EDLs) in channels with heterogeneous surface charge. This is accomplished by applying a voltage bias to a gate electrode embedded within the channel wall, tuning the surface charge in a region of the channel and significantly altering the charge density and ionic strength in that region relative to the rest of the channel. The resulting nonuniform electromigration fluxes in the different regions serve to stack charged sample ions at an interface where a step change in zeta potential occurs, providing enhancement ratios superior to those exhibited in traditional microchannel FASS. Numerical simulations are performed to demonstrate the phenomenon, and resulting velocity and salt concentration profiles show good agreement with analytical results.

  10. Characterisation of charge voltage of lead-acid batteries: application to the charge control strategy in photovoltaic systems

    Energy Technology Data Exchange (ETDEWEB)

    Vela, N. [CIEMAT-DER, Madrid (Spain). Laboratorio de Energia Solar Fotovoltaica; Aguilera, J. [Universidad de Jaen (Spain). Escuela Politecnica Superior

    2006-12-15

    In stand-alone photovoltaic (PV) systems, charge controllers prevent excessive battery overcharge by interrupting or limiting the current flow from the PV array to the battery when the battery becomes fully charged. Charge regulation is most often accomplished by limiting the battery voltage to a predetermined value or cut-off voltage, higher than the gassing voltage. These regulation voltages are dependent on the temperature and battery charge current. An adequate selection of overcharge cut-off voltage for each battery type and operating conditions would maintain the highest battery state of charge without causing significant overcharge thus improving battery performance and reliability. To perform this work, a sample of nine different lead-acid batteries, typically used in stand-alone PV systems including vented and sealed batteries with 2 V cells and monoblock configurations have been selected. This paper presents simple mathematical expressions fitting two charge characteristic voltages: the gassing voltage (V{sub g}) and the end-of charge voltage (V{sub fc}) as function of charge current and temperature for the tested batteries. With these expressions, we have calculated V{sub g} and V{sub fc} at different current rates. An analysis of the different values obtained is presented here focusing in the implication in control strategies of batteries in stand-alone PV systems. (author)

  11. Charge sniffer for electrostatics demonstrations

    Science.gov (United States)

    Dinca, Mihai P.

    2011-02-01

    An electronic electroscope with a special design for demonstrations and experiments on static electricity is described. It operates as an electric charge sniffer by detecting slightly charged objects when they are brought to the front of its sensing electrode. The sniffer has the advantage of combining high directional sensitivity with a logarithmic bar display. It allows for the identification of electric charge polarity during charge separation by friction, peeling, electrostatic induction, batteries, or secondary coils of power transformers. Other experiments in electrostatics, such as observing the electric field of an oscillating dipole and the distance dependence of the electric field generated by simple charge configurations, are also described.

  12. Antiproton charge radius

    Science.gov (United States)

    Crivelli, P.; Cooke, D.; Heiss, M. W.

    2016-09-01

    The upcoming operation of the extra low energy antiprotons ring at CERN, the upgrade of the antiproton decelerator (AD), and the installation in the AD hall of an intense slow positron beam with an expected flux of 1 08 e+ /s will open the possibility for new experiments with antihydrogen (H ¯). Here we propose a scheme to measure the Lamb shift of H ¯. For four months of data taking, we anticipate an uncertainty of 100 ppm. This will provide a test of C P T and the first determination of the antiproton charge radius at the level of 10%.

  13. Price Based Electric Vehicle Charging

    DEFF Research Database (Denmark)

    Mahat, Pukar; Handl, Martin; Kanstrup, Kenneth

    2012-01-01

    It is expected that a lot of the new light vehicles in the future will be electrical vehicles (EV). The storage capacity of these EVs has the potential to complement renewable energy resources and mitigate its intermittency. However, EV charging may have negative impact on the power grid. This pa......It is expected that a lot of the new light vehicles in the future will be electrical vehicles (EV). The storage capacity of these EVs has the potential to complement renewable energy resources and mitigate its intermittency. However, EV charging may have negative impact on the power grid....... This paper investigates the impact on a Danish distribution system when the EV charging aims to reduce the charging cost by charging at the cheapest hours. Results show that the charging based on the price signal only will have adverse effect on the grid. The paper also proposes an alternate EV charging...

  14. Charged Galileon black holes

    CERN Document Server

    Babichev, Eugeny; Hassaine, Mokhtar

    2015-01-01

    We consider an Abelian gauge field coupled to a particular truncation of Horndeski theory. The Galileon field has translation symmetry and couples non minimally both to the metric and the gauge field. When the gauge-scalar coupling is zero the gauge field reduces to a standard Maxwell field. By taking into account the symmetries of the action, we construct charged black hole solutions. Allowing the scalar field to softly break symmetries of spacetime we construct black holes where the scalar field is regular on the black hole event horizon. Some of these solutions can be interpreted as the equivalent of Reissner-Nordstrom black holes of scalar tensor theories with a non trivial scalar field. A self tuning black hole solution found previously is extended to the presence of dyonic charge without affecting whatsoever the self tuning of a large positive cosmological constant. Finally, for a general shift invariant scalar tensor theory we demonstrate that the scalar field Ansatz and method we employ are mathematic...

  15. Charged Dust Aggregate Interactions

    Science.gov (United States)

    Matthews, Lorin; Hyde, Truell

    2015-11-01

    A proper understanding of the behavior of dust particle aggregates immersed in a complex plasma first requires a knowledge of the basic properties of the system. Among the most important of these are the net electrostatic charge and higher multipole moments on the dust aggregate as well as the manner in which the aggregate interacts with the local electrostatic fields. The formation of elongated, fractal-like aggregates levitating in the sheath electric field of a weakly ionized RF generated plasma discharge has recently been observed experimentally. The resulting data has shown that as aggregates approach one another, they can both accelerate and rotate. At equilibrium, aggregates are observed to levitate with regular spacing, rotating about their long axis aligned parallel to the sheath electric field. Since gas drag tends to slow any such rotation, energy must be constantly fed into the system in order to sustain it. A numerical model designed to analyze this motion provides both the electrostatic charge and higher multipole moments of the aggregate while including the forces due to thermophoresis, neutral gas drag, and the ion wakefield. This model will be used to investigate the ambient conditions leading to the observed interactions. This research is funded by NSF Grant 1414523.

  16. Charged Galileon black holes

    Science.gov (United States)

    Babichev, Eugeny; Charmousis, Christos; Hassaine, Mokhtar

    2015-05-01

    We consider an Abelian gauge field coupled to a particular truncation of Horndeski theory. The Galileon field has translation symmetry and couples non minimally both to the metric and the gauge field. When the gauge-scalar coupling is zero the gauge field reduces to a standard Maxwell field. By taking into account the symmetries of the action, we construct charged black hole solutions. Allowing the scalar field to softly break symmetries of spacetime we construct black holes where the scalar field is regular on the black hole event horizon. Some of these solutions can be interpreted as the equivalent of Reissner-Nordstrom black holes of scalar tensor theories with a non trivial scalar field. A self tuning black hole solution found previously is extended to the presence of dyonic charge without affecting whatsoever the self tuning of a large positive cosmological constant. Finally, for a general shift invariant scalar tensor theory we demonstrate that the scalar field Ansatz and method we employ are mathematically compatible with the field equations. This opens up the possibility for novel searches of hairy black holes in a far more general setting of Horndeski theory.

  17. Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems

    Science.gov (United States)

    Tuffner, Francis K [Richland, WA; Kintner-Meyer, Michael C. W. [Richland, WA; Hammerstrom, Donald J [West Richland, WA; Pratt, Richard M [Richland, WA

    2012-05-22

    Battery charging control methods, electric vehicle charging methods, battery charging apparatuses and rechargeable battery systems. According to one aspect, a battery charging control method includes accessing information regarding a presence of at least one of a surplus and a deficiency of electrical energy upon an electrical power distribution system at a plurality of different moments in time, and using the information, controlling an adjustment of an amount of the electrical energy provided from the electrical power distribution system to a rechargeable battery to charge the rechargeable battery.

  18. Charge Breeding of Radioactive Ions

    CERN Document Server

    Wenander, F J C

    2013-01-01

    Charge breeding is a technique to increase the charge state of ions, in many cases radioactive ions. The singly charged radioactive ions, produced in an isotope separator on-line facility, and extracted with a low kinetic energy of some tens of keV, are injected into a charge breeder, where the charge state is increased to Q. The transformed ions are either directed towards a dedicated experiment requiring highly charged ions, or post-accelerated to higher beam energies. In this paper the physics processes involved in the production of highly charged ions will be introduced, and the injection and extraction beam parameters of the charge breeder defined. A description of the three main charge-breeding methods is given, namely: electron stripping in gas jet or foil; external ion injection into an electron-beam ion source/trap (EBIS/T); and external ion injection into an electron cyclotron resonance ion source (ECRIS). In addition, some preparatory devices for charge breeding and practical beam delivery aspects ...

  19. Use of charging control guidelines for geosynchronous satellite design studies

    Science.gov (United States)

    Steves, N. J.

    1980-01-01

    Several of the principle guidelines from the Spacecraft Charging Design Guidelines Handbook are presented with illustrative examples. Use of the geomagnetic substorm specification to qualify satellite designs, the evaluation of satellite designs by using analytical modelling techniques, the use of selected materials and coatings to minimize charging, the tying of all conducting elements to a common ground, and the use of electrical filtering to protect circuits from discharge induced upsets are discussed. Discharge criteria and SCATHA data are excluded.

  20. Nanoengineered field induced charge separation membranes manufacture thereof

    Science.gov (United States)

    O'Brien, Kevin C.; Haslam, Jeffery J.; Bourcier, William L.; Floyd, III, William Clary

    2016-08-02

    A device according to one embodiment includes a porous membrane having a surface charge and pore configuration characterized by a double layer overlap effect being present in pores of the membrane, where the porous membrane includes functional groups that preferentially interact with either cations or anions. A device according to another embodiment includes a porous membrane having a surface charge in pores thereof sufficient to impart anion or cation selectivity in the pores. Additional devices, systems and methods are also presented.

  1. Music and Alterity Processes

    Directory of Open Access Journals (Sweden)

    Josep Martí

    2014-10-01

    Full Text Available The concept of alterity constitutes an important issue in anthropological research and, therefore, in the study of musical practices, as well. Without it, we could hardly understand other kinds of music situated in different spaces and time from the observer. In order to effectively approach these musical practices, we have to develop strategies to help us reduce as much as possible that which distorts the vision of the other. However, beyond the strictly epistemological and methodological issues, the study of music cannot ignore the ethical question related to the manner in which Western thought has understood and treated the other: through a hierarchical and stereotypical type of thinking based on the condition of otherness. Throughout the article, different alterity procedures are presented and discussed, such as synecdochization, exoticization, undervaluation, overvaluation, misunderstanding and exclusion. Taking these different alterity strategies into account may help us to better understand how the musical other is constructed, used and ultimately instrumentalized.

  2. Attention Alters Perceived Attractiveness.

    Science.gov (United States)

    Störmer, Viola S; Alvarez, George A

    2016-04-01

    Can attention alter the impression of a face? Previous studies showed that attention modulates the appearance of lower-level visual features. For instance, attention can make a simple stimulus appear to have higher contrast than it actually does. We tested whether attention can also alter the perception of a higher-order property-namely, facial attractiveness. We asked participants to judge the relative attractiveness of two faces after summoning their attention to one of the faces using a briefly presented visual cue. Across trials, participants judged the attended face to be more attractive than the same face when it was unattended. This effect was not due to decision or response biases, but rather was due to changes in perceptual processing of the faces. These results show that attention alters perceived facial attractiveness, and broadly demonstrate that attention can influence higher-level perception and may affect people's initial impressions of one another.

  3. Characterization of an atomic hydrogen source for charge exchange experiments

    Science.gov (United States)

    Leutenegger, M. A.; Beiersdorfer, P.; Betancourt-Martinez, G. L.; Brown, G. V.; Hell, N.; Kelley, R. L.; Kilbourne, C. A.; Magee, E. W.; Porter, F. S.

    2016-11-01

    We characterized the dissociation fraction of a thermal dissociation atomic hydrogen source by injecting the mixed atomic and molecular output of the source into an electron beam ion trap containing highly charged ions and recording the x-ray spectrum generated by charge exchange using a high-resolution x-ray calorimeter spectrometer. We exploit the fact that the charge exchange state-selective capture cross sections are very different for atomic and molecular hydrogen incident on the same ions, enabling a clear spectroscopic diagnostic of the neutral species.

  4. Characterization of an atomic hydrogen source for charge exchange experiments

    Energy Technology Data Exchange (ETDEWEB)

    Leutenegger, M. A. [NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771 (United States); CRESST/University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, Maryland 21250 (United States); Beiersdorfer, P.; Brown, G. V.; Magee, E. W. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States); Betancourt-Martinez, G. L. [NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771 (United States); University of Maryland College Park, College Park, Maryland 20742 (United States); Hell, N. [Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550 (United States); Dr. Karl-Remeis-Sternwarte and ECAP, FAU Erlangen-Nürnberg, Sternwartstr. 7, 96049 Bamberg (Germany); Kelley, R. L.; Kilbourne, C. A.; Porter, F. S. [NASA Goddard Space Flight Center, Code 662, Greenbelt, Maryland 20771 (United States)

    2016-11-15

    We characterized the dissociation fraction of a thermal dissociation atomic hydrogen source by injecting the mixed atomic and molecular output of the source into an electron beam ion trap containing highly charged ions and recording the x-ray spectrum generated by charge exchange using a high-resolution x-ray calorimeter spectrometer. We exploit the fact that the charge exchange state-selective capture cross sections are very different for atomic and molecular hydrogen incident on the same ions, enabling a clear spectroscopic diagnostic of the neutral species.

  5. Fractional lattice charge transport

    Science.gov (United States)

    Flach, Sergej; Khomeriki, Ramaz

    2017-01-01

    We consider the dynamics of noninteracting quantum particles on a square lattice in the presence of a magnetic flux α and a dc electric field E oriented along the lattice diagonal. In general, the adiabatic dynamics will be characterized by Bloch oscillations in the electrical field direction and dispersive ballistic transport in the perpendicular direction. For rational values of α and a corresponding discrete set of values of E(α) vanishing gaps in the spectrum induce a fractionalization of the charge in the perpendicular direction - while left movers are still performing dispersive ballistic transport, the complementary fraction of right movers is propagating in a dispersionless relativistic manner in the opposite direction. Generalizations and the possible probing of the effect with atomic Bose-Einstein condensates and photonic networks are discussed. Zak phase of respective band associated with gap closing regime has been computed and it is found converging to π/2 value. PMID:28102302

  6. Stable charged cosmic strings.

    Science.gov (United States)

    Weigel, H; Quandt, M; Graham, N

    2011-03-11

    We study the quantum stabilization of a cosmic string by a heavy fermion doublet in a reduced version of the standard model. We show that charged strings, obtained by populating fermionic bound state levels, become stable if the electroweak bosons are coupled to a fermion that is less than twice as heavy as the top quark. This result suggests that extraordinarily large fermion masses or unrealistic couplings are not required to bind a cosmic string in the standard model. Numerically we find the most favorable string profile to be a simple trough in the Higgs vacuum expectation value of radius ≈10(-18)  m. The vacuum remains stable in our model, because neutral strings are not energetically favored.

  7. Battery charging stations

    Energy Technology Data Exchange (ETDEWEB)

    Bergey, M.

    1997-12-01

    This paper discusses the concept of battery charging stations (BCSs), designed to service rural owners of battery power sources. Many such power sources now are transported to urban areas for recharging. A BCS provides the opportunity to locate these facilities closer to the user, is often powered by renewable sources, or hybrid systems, takes advantage of economies of scale, and has the potential to provide lower cost of service, better service, and better cost recovery than other rural electrification programs. Typical systems discussed can service 200 to 1200 people, and consist of stations powered by photovoltaics, wind/PV, wind/diesel, or diesel only. Examples of installed systems are presented, followed by cost figures, economic analysis, and typical system design and performance numbers.

  8. 12 CFR 226.4 - Finance charge.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Finance charge. 226.4 Section 226.4 Banks and... LENDING (REGULATION Z) General § 226.4 Finance charge. (a) Definition. The finance charge is the cost of...) Charges by third parties. The finance charge includes fees and amounts charged by someone other than...

  9. Low-charge-state linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Kim, J.W.

    1995-08-01

    A design is being developed for a low-charge-state linac suitable for injecting ATLAS with a low-charge-state, radioactive beam. Initial work indicates that the existing ATLAS interdigital superconducting accelerating structures, together with the superconducting quadrupole transverse focussing element discussed above, provides a basis for a high-performance low-charge-state linac. The initial 2 or 3 MV of such a linac could be based on a normally-conducting, low-frequency RFQ, possibly combined with 24-MHz superconducting interdigital structures. Beam dynamics studies of the whole low-charge-state post-accelerator section were carried out in early FY 1995.

  10. Butterflies with rotation and charge

    Science.gov (United States)

    Reynolds, Alan P.; Ross, Simon F.

    2016-11-01

    We explore the butterfly effect for black holes with rotation or charge. We perturb rotating BTZ and charged black holes in 2 + 1 dimensions by adding a small perturbation on one asymptotic region, described by a shock wave in the spacetime, and explore the effect of this shock wave on the length of geodesics through the wormhole and hence on correlation functions. We find the effect of the perturbation grows exponentially at a rate controlled by the temperature; dependence on the angular momentum or charge does not appear explicitly. We comment on issues affecting the extension to higher-dimensional charged black holes.

  11. Butterflies with rotation and charge

    CERN Document Server

    Reynolds, Alan P

    2016-01-01

    We explore the butterfly effect for black holes with rotation or charge. We perturb rotating BTZ and charged black holes in 2+1 dimensions by adding a small perturbation on one asymptotic region, described by a shock wave in the spacetime, and explore the effect of this shock wave on the length of geodesics through the wormhole and hence on correlation functions. We find the effect of the perturbation grows exponentially at a rate controlled by the temperature; dependence on the angular momentum or charge does not appear explicitly. We comment on issues affecting the extension to higher-dimensional charged black holes.

  12. Fractional Charge Definitions and Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Goldhaber, A.S.

    2004-06-04

    Fractional charge is known through theoretical and experimental discoveries of isolable objects carrying fractions of familiar charge units--electric charge Q, spin S, and the difference of baryon and lepton numbers B-L. With a few simple assumptions all these effects may be described using a generalized version of charge renormalization for locally conserved charges, in which medium correlations yield familiar adiabatic, continuous renormalization, or sometimes nonadiabatic, discrete renormalization. Fractional charges may be carried by fundamental particles or fundamental solitons. Either picture works for the simplest fractional-quantum-Hall-effect quasiholes, though the particle description is far more general. The only known fundamental solitons in three or fewer space dimensions d are the kink (d = 1), the vortex (d = 2), and the magnetic monopole (d = 3). Further, for a charge not intrinsically coupled to the topological charge of a soliton, only the kink and the monopole may carry fractional values. The same reasoning enforces fractional values of B-L for electrically charged elementary particles.

  13. Charge transport in polymeric transistors

    Directory of Open Access Journals (Sweden)

    Alberto Salleo

    2007-03-01

    Full Text Available Polymeric semiconductors have attracted much attention because of their possible use as active materials in printed electronics. Thin-film transistors (TFTs are a convenient tool for studying charge-transport physics in conjugated polymers. Two families of materials are reviewed here: fluorene copolymers and polythiophenes. Because charge transport is highly anisotropic in molecular conductors, the electrical properties of conjugated polymers are strongly dependent on microstructure. Molecular weight, polydispersity, and regioregularity all affect morphology and charge-transport in these materials. Charge transport models based on microstructure are instrumental in identifying the electrical bottlenecks in these materials.

  14. Charged Polaritons with Spin 1

    Directory of Open Access Journals (Sweden)

    Samoilov V.

    2011-04-01

    Full Text Available We present a new model for metal which is based on the stimulated vibration of independent charged Fermi-ions, representing as independent harmonic oscillators with natural frequencies, under action of longitudinal and transverse elastic waves. Due to application of the elastic wave-particle principle and ion-wave dualities, we predict the existence of two types of charged Polaritons with spin 1 which are induced by longitudinal and transverse elastic fields. As result of presented theory, at small wavenumbers, these charged polaritons represent charged phonons.

  15. Charge transport in nanoscale junctions.

    Science.gov (United States)

    Albrecht, Tim; Kornyshev, Alexei; Bjørnholm, Thomas

    2008-09-03

    the molecular level. Nanoscale charge transport experiments in ionic liquids extend the field to high temperatures and to systems with intriguing interfacial potential distributions. Other directions may include dye-sensitized solar cells, new sensor applications and diagnostic tools for the study of surface-bound single molecules. Another motivation for this special issue is thus to highlight activities across different research communities with nanoscale charge transport as a common denominator. This special issue gathers 27 articles by scientists from the United States, Germany, the UK, Denmark, Russia, France, Israel, Canada, Australia, Sweden, Switzerland, the Netherlands, Belgium and Singapore; it gives us a flavour of the current state-of-the-art of this diverse research area. While based on contributions from many renowned groups and institutions, it obviously cannot claim to represent all groups active in this very broad area. Moreover, a number of world-leading groups were unable to take part in this project within the allocated time limit. Nevertheless, we regard the current selection of papers to be representative enough for the reader to draw their own conclusions about the current status of the field. Each paper is original and has its own merit, as all papers in Journal of Physics: Condensed Matter special issues are subjected to the same scrutiny as regular contributions. The Guest Editors have deliberately not defined the specific subjects covered in this issue. These came out logically from the development of this area, for example: 'Traditional' solid state nanojunctions based on adsorbed layers, oxide films or nanowires sandwiched between two electrodes: effects of molecular structure (aromaticity, anchoring groups), symmetry, orientation, dynamics (noise patterns) and current-induced heating. Various 'physical effects': inelastic tunnelling and Coulomb blockade, polaron effects, switching modes, and negative differential resistance; the role of

  16. Putative resolution of the EEEE selectivity paradox in L-type Ca2+ and bacterial Na+ biological ion channels

    Science.gov (United States)

    Kaufman, I. Kh; Luchinsky, D. G.; Gibby, W. A. T.; McClintock, P. V. E.; Eisenberg, R. S.

    2016-05-01

    The highly selective permeation of ions through biological ion channels can be described and explained in terms of fluctuational dynamics under the influence of powerful electrostatic forces. Hence valence selectivity, e.g. between Ca2+ and Na+ in calcium and sodium channels, can be described in terms of ionic Coulomb blockade, which gives rise to distinct conduction bands and stop-bands as the fixed negative charge Q f at the selectivity filter of the channel is varied. This picture accounts successfully for a wide range of conduction phenomena in a diversity of ion channels. A disturbing anomaly, however, is that what appears to be the same electrostatic charge and structure (the so-called EEEE motif) seems to select Na+ conduction in bacterial channels but Ca2+ conduction in mammalian channels. As a possible resolution of this paradox it is hypothesised that an additional charged protein residue on the permeation path of the mammalian channel increases |{{Q}f}| by e, thereby altering the selectivity from Na+ to Ca2+. Experiments are proposed that will enable the hypothesis to be tested.

  17. PUBLIC ACCEPTANCE OF ROAD-USER CHARGING

    Directory of Open Access Journals (Sweden)

    Neil THORPE

    2002-01-01

    Full Text Available This paper focuses upon public attitudes to and public acceptance of road-user charging as an effective means of managing travel demand, with the overall aim of identifying the characteristics of key interest groups, the kinds of attitudes they hold and their preferences for the distribution of the benefits of generated net revenues and released roadspace. It is argued that this knowledge can play a pivotal role in the design of road-user charging systems that satisfy two important criteria – namely, that they are capable of achieving their stated objectives and are generally acceptable to the public. A case-study of three toll-rings used for revenue generation by the Norwegian cities of Bergen, Oslo and Trondheim is selected, where a team of Norwegian interviewers administered a computer-based survey to a total of 756 respondents. Results of the analyses of the attitudinal data collected raise concerns about the approach of introducing initially low levels of road-use charge, designed to have negligible impacts on travel behaviour but to raise revenues to fund necessary improvements to public transport, both to familiarise private car-users with the principles of a pay-as-you-go system of charging and hopefully to reduce levels of public opposition prior to the introduction of the longer term objective of higher charges for traffic restraint. The timescale over which charges are increased may be crucial in terms of balancing a resistance to change in the longer term against the credibility of a system whose objectives are modified in the relatively short-term. The key conclusion from the first Stated Preference exercise is that there is a high degree of consensus among individuals on the importance of investing significant amounts of net revenues in new road infrastructure as well as improved public transport. The second Stated Preference exercise highlights respondents' concerns that the benefits in improved network performance achieved by a

  18. Molecular and structural insight into lysine selection on substrate and ubiquitin lysine 48 by the ubiquitin-conjugating enzyme Cdc34

    DEFF Research Database (Denmark)

    Suryadinata, Randy; Holien, Jessica K; Yang, George

    2013-01-01

    The attachment of ubiquitin (Ub) to lysines on substrates or itself by ubiquitin-conjugating (E2) and ubiquitin ligase (E3) enzymes results in protein ubiquitination. Lysine selection is important for generating diverse substrate-Ub structures and targeting proteins to different fates; however......, the mechanisms of lysine selection are not clearly understood. The positioning of lysine(s) toward the E2/E3 active site and residues proximal to lysines are critical in their selection. We investigated determinants of lysine specificity of the ubiquitin-conjugating enzyme Cdc34, toward substrate and Ub lysines....... Evaluation of the relative importance of different residues positioned -2, -1, +1 and +2 toward ubiquitination of its substrate, Sic1, on lysine 50 showed that charged residues in the -1 and -2 positions negatively impact on ubiquitination. Modeling suggests that charged residues at these positions alter...

  19. Highly Charged Clusters of Fullerenes: Charge Mobility and Appearance Sizes

    Science.gov (United States)

    Manil, B.; Maunoury, L.; Huber, B. A.; Jensen, J.; Schmidt, H. T.; Zettergren, H.; Cederquist, H.; Tomita, S.; Hvelplund, P.

    2003-11-01

    Clusters of fullerenes (C60,C70)n are produced in a gas aggregation source and are multiply ionized in collisions with highly charged Xe20+,30+ ions. Their stabilities and decay processes are analyzed with high-resolution time-of-flight mass spectrometry. Fullerene clusters in charge states up to q=5 have been observed and appearance sizes are found to be as small as napp=5, 10, 21, and 33 for q=2, 3, 4, and 5, respectively. The analysis of the multicoincident fragmentation spectra indicates a high charge mobility. This is in contrast to charge localization effects which have been reported for Arq+n rare gas clusters. Clusters of fullerenes are found to be conducting when multiply charged.

  20. Charge transfer in multicomponent oxides

    Science.gov (United States)

    Kohan, A. F.; Ceder, G.

    1998-02-01

    The transfer of charge between different ions in an oxide plays an essential role in the stability of these compounds. Since small variations in charge can introduce large changes in the total energy, a correct description of this phenomenon is critical. In this work, we show that the ionic charge in oxides can strongly depend on its atomic environment. A model to assign point charges to atoms as a function of their atomic environment has recently been proposed for binary alloys [C. Wolverton, A. Zunger, S. Froyen, and S.-H. Wei, Phys. Rev. B 54, 7843 (1996)] and proven to be very successful in screened solids such as semiconductors and metals. Here, we extend this formalism to multicomponent oxides and we assess its applicability. The simple point-charge model predicts a linear relation between the charge on an atom and the number of unlike neighbors, and between the net value of the charge and the Coulomb field at a given site. The applicability of this approach is tested in a large-supercell self-consistent tight-binding calculation for a random Zr-Ca-O alloy. The observed fluctuations of the ionic charge about the average linear behavior (as a function of the number of unlike neighbors) was larger than 0.25 electrons even when many shells of atomic neighbors were considered in the fit. This variation is significant since it can introduce large errors in the electrostatic energy. On the other hand, for small absolute values of the charge, the ionic charge varied linearly with the Coulomb field, in agreement with previous findings. However, for large Coulomb fields, this function saturates at the formal chemical charge.

  1. Smart electric vehicle (EV) charging and grid integration apparatus and methods

    Energy Technology Data Exchange (ETDEWEB)

    Gadh, Rajit; Mal, Siddhartha; Prabhu, Shivanand; Chu, Chi-Cheng; Sheikh, Omar; Chung, Ching-Yen; He, Lei; Xiao, Bingjun; Shi, Yiyu

    2015-05-05

    An expert system manages a power grid wherein charging stations are connected to the power grid, with electric vehicles connected to the charging stations, whereby the expert system selectively backfills power from connected electric vehicles to the power grid through a grid tie inverter (if present) within the charging stations. In more traditional usage, the expert system allows for electric vehicle charging, coupled with user preferences as to charge time, charge cost, and charging station capabilities, without exceeding the power grid capacity at any point. A robust yet accurate state of charge (SOC) calculation method is also presented, whereby initially an open circuit voltage (OCV) based on sampled battery voltages and currents is calculated, and then the SOC is obtained based on a mapping between a previously measured reference OCV (ROCV) and SOC. The OCV-SOC calculation method accommodates likely any battery type with any current profile.

  2. Escherichia coli O157:H7 Cells Exposed to Lettuce Leaf Lysate in Refrigerated Conditions Exhibit Differential Expression of Selected Virulence and Adhesion-Related Genes with Altered Mammalian Cell Adherence.

    Science.gov (United States)

    Kennedy, Nicole M; Mukherjee, Nabanita; Banerjee, Pratik

    2016-07-01

    Contamination by and persistence of pathogenic bacteria in ready-to-eat produce have emerged as significant food safety and public health concerns. Viable produceborne pathogens cope with several stresses (e.g., temperature fluctuations and lowtemperature storage) during production and storage of the commodities. In this study, we investigated the impact of transient cold shock on Escherichia coli O157:H7 (EcO157) cells in a produce matrix (romaine lettuce leaf lysate). EcO157 cells were exposed to 25°C for 1 h, 4°C for 1 h, and 4°C for 10 min in lettuce lysate. The expression of selected genes coding for virulence, stress response, and heat and cold shock proteins was quantified by real-time quantitative reverse transcription PCR assay. Treated EcO157 cells adhered to MAC-T mammalian cells were enumerated by in vitro bioassay. Expression of the Shiga toxin 1 gene (stx1a) was upregulated significantly (P < 0.05) upon cold shock treatments, but virulence genes related to EcO157 attachment (eaeA, lpfA, and hcpA) were down-regulated. Two key members of the cold shock regulon, cold shock protein (cspA) and gyrA, were significantly induced (P < 0.05) at the refrigeration temperature (4°C). Significant upregulation of an SOS response gene, recA, was also observed. E. coli heat shock regulon member grpE was induced, but a universal stress protein (uspA) was downregulated at the refrigeration temperatures in lettuce lysate. The adhesion assay revealed a temperature-dependent reduction in the attachment of cold-shocked EcO157 cells. The results of the current study indicate a reduction in the attachment of cold-shocked EcO157 to epithelial cells and higher levels of Shiga toxin gene expression at the molecular level.

  3. The influence of combined magnesium and vanadate administration on the level of some elements in selected rat organs: V-Mg interactions and the role of iron-essential protein (DMT-1) in the mechanism underlying altered tissues iron level.

    Science.gov (United States)

    Scibior, Agnieszka; Adamczyk, Agnieszka; Gołębiowska, Dorota; Niedźwiecka, Irmina; Fornal, Emilia

    2014-04-01

    The effect of 12 week co-administration of sodium metavanadate (SMV) and magnesium sulfate (MS) on the levels of some elements in selected rats' organs and an attempt to elucidate a role of divalent metal transporter 1 (DMT-1) in the mechanism(s) of the SMV-induced disorders in some tissue Fe homeostasis were studied. SMV taken up separately or in combination with MS may pose a risk of the rise and shortage of the total hepatic and splenic Fe and Cu contents, respectively, cerebral Fe deficiency, splenic Ca deposition, and the hepatic, renal, and cerebral DMT-1 down-regulation. When administered alone, SMV may also cause the decrease in the total renal Fe and Cu contents. A visible protective effect of Mg against the renal and cerebral V accumulation and the decrease in the renal Fe and Cu contents during the SMV-MS co-administration together with our previous findings suggest a beneficial role of Mg at SMV exposure. Further, the SMV-induced fall in total iron binding capacity (TIBC), reported previously, and its correlations with the hepatic, splenic, and cerebral Fe levels allow us to suggest that diminished TIBC could be partly involved in the mechanism(s) responsible for the dramatic redistribution of Fe in those tissues. Finally, DMT-1, which potentially could participate in the hepatic non-transferrin Fe-bound uptake, does not play a significant role in this process indicating the need for studying other Fe transporters to more precisely elucidate molecular mechanism(s) underlying the hepatic Fe loading in our experimental conditions.

  4. Quantum charged rigid membrane

    Energy Technology Data Exchange (ETDEWEB)

    Cordero, Ruben [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del I.P.N., Unidad Adolfo Lopez Mateos, Edificio 9, 07738 Mexico, D.F. (Mexico); Molgado, Alberto [Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, Zacatecas Zac. (Mexico); Rojas, Efrain, E-mail: cordero@esfm.ipn.mx, E-mail: amolgado@fisica.uaz.edu.mx, E-mail: efrojas@uv.mx [Departamento de Fisica, Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)

    2011-03-21

    The early Dirac proposal to model the electron as a charged membrane is reviewed. A rigidity term, instead of the natural membrane tension, involving linearly the extrinsic curvature of the worldvolume swept out by the membrane is considered in the action modeling the bubble in the presence of an electromagnetic field. We set up this model as a genuine second-order derivative theory by considering a non-trivial boundary term which plays a relevant part in our formulation. The Lagrangian in question is linear in the bubble acceleration and by means of the Ostrogradski-Hamiltonian approach, we observed that the theory comprises the management of both first- and second-class constraints. We thus show that our second-order approach is robust allowing for a proper quantization. We found an effective quantum potential which permits us to compute bounded states for the system. We comment on the possibility of describing brane world universes by invoking this kind of second-order correction terms.

  5. Quantum charged rigid membrane

    CERN Document Server

    Cordero, Ruben; Rojas, Efrain

    2010-01-01

    The early Dirac proposal to model the electron as a charged membrane is reviewed. A rigidity term, instead of the natural membrane tension, involving linearly the extrinsic curvature of the worldvolume swept out by the membrane is considered in the action modeling the bubble in the presence of an electromagnetic field. We set up this model as a genuine second-order derivative theory by considering a non-trivial boundary term which plays a relevant part in our formulation. The Lagrangian in question is linear in the bubble acceleration and by means of the Ostrogradski-Hamiltonian approach we observed that the theory comprises the management of both first- and second-class constraints. We show thus that our second-order approach is robust allowing for a proper quantization. We found an effective quantum potential which permits to compute bounded states for the system. We comment on the possibility of describing brane world universes by invoking this kind of second-order correction terms.

  6. Calculating charged defects using CRYSTAL

    Science.gov (United States)

    Bailey, Christine L.; Liborio, Leandro; Mallia, Giuseppe; Tomić, Stanko; Harrison, Nicholas M.

    2010-07-01

    The methodology for the calculation of charged defects using the CRYSTAL program is discussed. Two example calculations are used to illustrate the methodology: He+ ions in a vacuum and two intrinsic charged defects, Cu vacancies and Ga substitution for Cu, in the chalcopyrite CuGaS2.

  7. Metallic charge stripes in cuprates

    OpenAIRE

    Tranquada, J. M.

    2003-01-01

    Some recent evidence for the existence of dynamic, metallic stripes in the 214-family of cuprates is reviewed. The mechanism of stripe pinning is considered, and changes in the charge density within stripes between the pinned and dynamic phases is discussed. From a purely experimental perspective, dynamic charge stripes are fully compatible with nodal ``quasiparticles'' and other electronic properties common to all superconducting cuprates.

  8. Filling of charged cylindrical capillaries

    NARCIS (Netherlands)

    Das, Siddhartha; Chanda, Sourayon; Eijkel, J.C.T.; Tas, N.R.; Chakraborty, Suman; Mitra, Sushanta K.

    2014-01-01

    We provide an analytical model to describe the filling dynamics of horizontal cylindrical capillaries having charged walls. The presence of surface charge leads to two distinct effects: It leads to a retarding electrical force on the liquid column and also causes a reduced viscous drag force because

  9. Charge transport in amorphous oligothiophenes

    Energy Technology Data Exchange (ETDEWEB)

    Schrader, Manuel; Baumeier, Bjoern; Andrienko, Denis [Max-Planck-Institute for Polymer Research, Ackermannweg 10, 55128 Mainz (Germany); Elschner, Chris; Riede, Moritz; Leo, Karl [TU Dresden, Institute of Applied Photophysics, Mommsenstr. 13, 01062 Dresden (Germany)

    2011-07-01

    Organic semiconducting materials are needed for emerging devices such as photovoltaic solar cells. In this work we combine first principle calculations, molecular dynamics and kinetic Monte Carlo simulations to study charge transport in dicyanovinyl oligothiophenes of different lengths. Poole-Frenkel behavior of the charge carrier mobility is rationalized based on electrostatic and conformational disorder.

  10. Ressourcenorientierte Diagnostik im Alter

    OpenAIRE

    Forstmeier, Simon; Maercker, Andreas

    2008-01-01

    Trotz der im Alter zunehmenden körperlichen, kognitiven und sozialen Verlusten bleibt das subjektive Wohlbefinden relativ stabil. Dies weist auf die vielen Ressourcen älterer Menschen hin. Dieser Artikel stellt für die klinische Ressourcendiagnostik relevante Verfahren vor und erläutert die zugrunde liegenden Konzepte. Berücksichtigt werden Aktivitäten und Erlebnisse als Ressourcen, emotionale Ressourcen (positiver Affekt, Lebenszufriedenheit, Selbstwerterleben, Lebensqualität), motivationale...

  11. Holography, charge and baryon asymmetry

    CERN Document Server

    Mongan, T R

    2009-01-01

    The holographic principle indicates the finite number of bits of information available on the particle horizon describes all physics within the horizon. Linking information on the horizon with Standard Model particles requires a holographic model describing constituents (preons) of Standard Model particles in terms of bits of information on the horizon. Standard Model particles have charges 0, 1/3, 2/3 or 1 in units of the electron charge e, so bits in a preon model must be identified with fractional charge. Energy must be transferred to change the state of a bit, and labeling the low energy state of a bit e/3n and the high energy state -e/3n amounts to defining electric charge. Any such charged preon model will produce more protons than anti-protons at the time of baryogenesis and require baryon asymmetry. It will also produce more positrons than electrons, as suggested by astrophysical measurements.

  12. Charge order in cuprate superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Bulut, Sinan; Kampf, Arno P. [Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute of Physics, University of Augsburg (Germany); Atkinson, Bill A. [Department of Physics and Astronomy, Trent University, Peterborough, Ontario (Canada)

    2015-07-01

    Motivated by widespread experimental evidence of charge orders in underdoped cuprate superconductors, we study a three band model of a cuprate plane. Our calculations start from a pseudogap-like normal system with a reconstructed Fermi surface, and we search for charge instabilities. From the charge susceptibilities, we identify a charge ordering instability with an ordering wavevector, q*, that matches experimental results not only with respect to the doping dependence but more importantly regarding its magnitude and direction. Namely, q* points along the Brillouin zone axes. Thus, our results clarify the discrepancy between many recent theoretical calculations and the experiments. We extend this calculation towards possible loop current instabilities and the charge ordering pattern in bilayer systems.

  13. Grain charging in protoplanetary discs

    CERN Document Server

    Ilgner, Martin

    2011-01-01

    Recent work identified a growth barrier for dust coagulation that originates in the electric repulsion between colliding particles. Depending on its charge state, dust material may have the potential to control key processes towards planet formation such as MHD (magnetohydrodynamic) turbulence and grain growth which are coupled in a two-way process. We quantify the grain charging at different stages of disc evolution and differentiate between two very extreme cases: compact spherical grains and aggregates with fractal dimension D_f = 2. Applying a simple chemical network that accounts for collisional charging of grains, we provide a semi-analytical solution. This allowed us to calculate the equilibrium population of grain charges and the ionisation fraction efficiently. The grain charging was evaluated for different dynamical environments ranging from static to non-stationary disc configurations. The results show that the adsorption/desorption of neutral gas-phase heavy metals, such as magnesium, effects the ...

  14. Electrostatic charging of jumping droplets

    Science.gov (United States)

    Miljkovic, Nenad; Preston, Daniel J.; Enright, Ryan; Wang, Evelyn N.

    2013-09-01

    With the broad interest in and development of superhydrophobic surfaces for self-cleaning, condensation heat transfer enhancement and anti-icing applications, more detailed insights on droplet interactions on these surfaces have emerged. Specifically, when two droplets coalesce, they can spontaneously jump away from a superhydrophobic surface due to the release of excess surface energy. Here we show that jumping droplets gain a net positive charge that causes them to repel each other mid-flight. We used electric fields to quantify the charge on the droplets and identified the mechanism for the charge accumulation, which is associated with the formation of the electric double layer at the droplet-surface interface. The observation of droplet charge accumulation provides insight into jumping droplet physics as well as processes involving charged liquid droplets. Furthermore, this work is a starting point for more advanced approaches for enhancing jumping droplet surface performance by using external electric fields to control droplet jumping.

  15. Static Gas-Charging Plug

    Science.gov (United States)

    Indoe, William

    2012-01-01

    A gas-charging plug can be easily analyzed for random vibration. The design features two steeped O-rings in a radial configuration at two different diameters, with a 0.050-in. (.1.3-mm) diameter through-hole between the two O-rings. In the charging state, the top O-ring is engaged and sealing. The bottom O-ring outer diameter is not squeezed, and allows air to flow by it into the tank. The inner diameter is stretched to plug the gland diameter, and is restrained by the O-ring groove. The charging port bushing provides mechanical stop to restrain the plug during gas charge removal. It also prevents the plug from becoming a projectile when removing gas charge from the accumulator. The plug can easily be verified after installation to ensure leakage requirements are met.

  16. Piston-assisted charge pumping

    CERN Document Server

    Kaur, D; Mourokh, L

    2015-01-01

    We examine charge transport through a system of three sites connected in series in the situation when an oscillating charged piston modulates the energy of the middle site. We show that with an appropriate set of parameters, charge can be transferred against an applied voltage. In this scenario, when the oscillating piston shifts away from the middle site, the energy of the site decreases and it is populated by a charge transferred from the lower energy site. On the other hand, when the piston returns to close proximity, the energy of the middle site increases and it is depopulated by the higher energy site. Thus through this process, the charge is pumped against the potential gradient. Our results can explain the process of proton pumping in one of the mitochondrial enzymes, Complex I. Moreover, this mechanism can be used for electron pumping in semiconductor nanostructures.

  17. Null Mutations of Group A Streptococcus Orphan Kinase RocA: Selection in Mouse Infection and Comparison with CovS Mutations in Alteration of In Vitro and In Vivo Protease SpeB Expression and Virulence.

    Science.gov (United States)

    Feng, Wenchao; Minor, Dylan; Liu, Mengyao; Li, Jinquan; Ishaq, Suzanne L; Yeoman, Carl; Lei, Benfang

    2017-01-01

    Group A Streptococcus (GAS) acquires mutations of the virulence regulator CovRS in human and mouse infections, and these mutations result in the upregulation of virulence genes and the downregulation of the protease SpeB. To identify in vivo mutants with novel phenotypes, GAS isolates from infected mice were screened by enzymatic assays for SpeB and the platelet-activating factor acetylhydrolase Sse, and a new type of variant that had enhanced Sse expression and normal levels of SpeB production was identified (the variants had a phenotype referred to as enhanced Sse activity [Sse(A+)] and normal SpeB activity [SpeB(A+)]). Sse(A+) SpeB(A+) variants had transcript levels of CovRS-controlled virulence genes comparable to those of a covS mutant but had no covRS mutations. Genome resequencing of an Sse(A+) SpeB(A+) isolate identified a C605A nonsense mutation in orphan kinase gene rocA, and 6 other Sse(A+) SpeB(A+) isolates also had nonsense mutations or small indels in rocA RocA and CovS mutants had similar levels of enhancement of the expression of CovRS-controlled virulence genes at the exponential growth phase; however, mutations of RocA but not mutations of CovS did not result in the downregulation of speB transcription at stationary growth phase or in subcutaneous infection of mice. GAS with RocA and CovS mutations caused greater enhancement of the expression of hasA than spyCEP in mouse skin infection than wild-type GAS did. RocA mutants ranked between wild-type GAS and CovS mutants in skin invasion, inhibition of neutrophil recruitment, and virulence in subcutaneous infection of mice. Thus, GAS RocA mutants can be selected in subcutaneous infections in mice and exhibit gene expression patterns and virulences distinct from those of CovS mutants. The findings provide novel information for understanding GAS fitness mutations in vivo, virulence gene regulation, in vivo gene expression, and virulence. Copyright © 2016 American Society for Microbiology.

  18. Shock Electrodeposition in Charged Porous Media

    CERN Document Server

    Han, Ji-Hyung

    2015-01-01

    It is shown that surface conduction in porous media can drastically alter the stability and morphology of electrodeposition at high rates, above the diffusion-limited current. Copper electrodeposits are visualized by scanning electron microscopy and energy dispersive spectroscopy in cellulose nitrate membranes, whose pores are coated with positive or negative charged polymers. Above the limiting current, surface conduction inhibits growth in the positive membrane and produces irregular dendrites, while it enhances growth and suppresses dendrites behind a deionization shock in the negative membrane. The discovery of uniform growth contradicts quasi-steady leaky membrane models, which are in the same universality class as unstable Laplacian growth, and indicates the importance of transient electro-diffusion or electro-osmotic dispersion. Shock electrodeposition could be exploited for high-rate recharging of metal batteries or manufacturing of metal matrix composite coatings.

  19. Highly efficient charged particle veto detector CUP

    Energy Technology Data Exchange (ETDEWEB)

    Palacz, M. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland)]. E-mail: palacz@slcj.uw.edu.pl; Nyberg, J. [Department of Radiation Sciences, Uppsala University, Uppsala (Sweden); Bednarczyk, P. [Institute de Recherches Subatomiques, Strasbourg (France); Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow (Poland); Dworski, J. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland); Gorska, M. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany); Iwanicki, J. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland); Kapusta, M. [Soltan Institute for Nuclear Studies, Swierk (Poland); Kownacki, J. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland); Kulczycka, E. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland); Lagergren, K. [Royal Institute of Technology, Stockholm (Sweden); Moszynski, M. [Soltan Institute for Nuclear Studies, Swierk (Poland); Pienkowski, L. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland); Stolarz, A. [Heavy Ion Laboratory, Warsaw University, ul. Pasteura 5A, PL 02-093 Warsaw (Poland); Wolski, D. [Soltan Institute for Nuclear Studies, Swierk (Poland); Zieblinski, M. [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow (Poland)

    2005-09-11

    A novel, highly efficient, plastic scintillator detector has been constructed. The primary application of the detector is to act as a veto device in heavy-ion-induced fusion-evaporation reactions, in which the structure of proton-rich nuclides is investigated by {gamma}-ray spectroscopy methods. The detector rejects events in which light charged particles, like protons and {alpha} particles, are emitted in the evaporation process, facilitating selection of reaction channels associated with emission of only neutrons. The detector was used in a EUROBALL experiment, with achieved efficiencies of 80% and 63% for protons and {alpha} particles, respectively. The design of the detector, its performance and limitations are discussed.

  20. R-charge Conservation and More in Factorizable and Non-Factorizable Orbifolds

    CERN Document Server

    Bizet, Nana Geraldine Cabo; Pena, Damian Kaloni Mayorga; Parameswaran, Susha L; Schmitz, Matthias; Zavala, Ivonne

    2013-01-01

    We consider the string theory origin of R-charge conservation laws in heterotic orbifold compactifications, deriving the corresponding string coupling selection rule for factorizable and non-factorizable orbifolds, with prime ordered and non-prime ordered point groups. R-charge conservation arises due to symmetries among the worldsheet instantons that can mediate the couplings. Among our results is a previously missed non-trivial contribution to the conserved R-charges from the Gamma-phases in non-prime orbifolds, which weakens the R-charge selection rule. Symmetries among the worldsheet instantons can also lead to additional selection rules for some couplings. We make a similar analysis for Rule 4 or the 'torus lattice selection rule'. Moreover, we identify a new string selection rule, that we call Rule 6 or the 'coset vector selection rule'.

  1. Portable refrigerant charge meter and method for determining the actual refrigerant charge in HVAC systems

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhiming; Abdelaziz, Omar; LaClair, Tim L.

    2017-08-08

    A refrigerant charge meter and a method for determining the actual refrigerant charge in HVAC systems are described. The meter includes means for determining an optimum refrigerant charge from system subcooling and system component parameters. The meter also includes means for determining the ratio of the actual refrigerant charge to the optimum refrigerant charge. Finally, the meter includes means for determining the actual refrigerant charge from the optimum refrigerant charge and the ratio of the actual refrigerant charge to the optimum refrigerant charge.

  2. Charge transfer in the cold Yb$^+$ + Rb collisions

    CERN Document Server

    Sayfutyarova, Elvira R; Yakovleva, Svetlana A; Belyaev, Andrey K

    2013-01-01

    Charge-transfer cold Yb$^+$ + Rb collision dynamics is investigated theoretically using high-level {\\it ab initio} potential energy curves, dipole moment functions and nonadiabatic coupling matrix elements. Within the scalar-relativistic approximation, the radiative transitions from the entrance $A^1\\Sigma^+$ to the ground $X^1\\Sigma^+$ state are found to be the only efficient charge-transfer pathway. The spin-orbit coupling does not open other efficient pathways, but alters the potential energy curves and the transition dipole moment for the $A-X$ pair of states. The radiative, as well as the nonradiative, charge-transfer cross sections calculated within the $10^{-3}-10$ cm$^{-1}$ collision energy range exhibit all features of the Langevin ion-atom collision regime, including a rich structure associated with centrifugal barrier tunneling (orbiting) resonances. Theoretical rate coefficients for two Yb isotopes agree well with those measured by immersing Yb$^+$ ion in an ultracold Rb ensemble in a hybrid trap....

  3. Simulation for signal charge transfer of charge coupled devices

    Institute of Scientific and Technical Information of China (English)

    Wang Zujun; Liu Yinong; Chen Wei; Tang Benqi; Xiao Zhigang; Huang Shaoyan; Liu Minbo; Zhang Yong

    2009-01-01

    Physical device models and numerical processing methods are presented to simulate a linear buried channel charge coupled devices (CCDs). The dynamic transfer process of CCD is carried out by a three-phase clock pulse driver. By using the semiconductor device simulation software MEDICI, dynamic transfer pictures of signal charges cells, electron concentration and electrostatic potential are presented. The key parameters of CCD such as charge transfer efficiency (CTE) and dark electrons are numerically simulated. The simulation results agree with the theoretic and experimental results.

  4. Radiation by moving charges

    Energy Technology Data Exchange (ETDEWEB)

    Geloni, Gianluca [European XFEL GmbH, Hamburg (Germany); Kocharyan, Vitali; Saldin, Evgeni [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2017-04-15

    It is generally accepted that in order to describe the dynamics of relativistic particles in the laboratory (lab) frame it is sufficient to take into account the relativistic dependence of the particle momenta on the velocity. This solution of the dynamics problem in the lab frame makes no reference to Lorentz transformations. For this reason they are not discussed in particle tracking calculations in accelerator and plasma physics. It is generally believed that the electrodynamics problem can be treated within the same ''single inertial frame'' description without reference to Lorentz transformations. In particular, in order to evaluate radiation fields arising from charged particles in motion we need to know their velocities and positions as a function of the lab frame time t. The relativistic motion of a particle in the lab frame is described by Newton's second law ''corrected'' for the relativistic dependence of momentum on velocity. It is assumed in all standard derivations that one can perform identification of the trajectories in the source part of the usual Maxwell's equations with the trajectories vector x(t) measured (or calculated by using the corrected Newton's second law) in the lab frame. This way of coupling fields and particles is considered since more than a century as the relativistically correct procedure.We argue that this procedure needs to be changed, and we demonstrate the following, completely counterintuitive statement: the results of conventional theory of radiation by relativistically moving charges are not consistent with the principle of relativity. In order to find the trajectory of a particle in the lab frame consistent with the usual Maxwell's equations, one needs to solve the dynamic equation inmanifestly covariant form by using the coordinate-independent proper time τ to parameterize the particle world-line in space-time. We show that there is a difference between &apos

  5. Charged particle and laser irradiation of selected materials

    Energy Technology Data Exchange (ETDEWEB)

    Svendsen, W.E.

    1996-11-01

    The main topics of the present thesis are the processes governing electronic sputtering of insulators and laser ablation of metals and insulators. The sputtering yield for electron bombardment of solid deuterium was investigated using quartz crystal microbalances as the measuring technique. The sputtering yield was measured with varying electron energy and deuterium film thickness. Laser ablation measurements of silver and nickel were carried out using a Nd:YAG laser. The effect of various experimental parameters such as background gas pressure (Ar, N{sub 2}), position of quartz crystals with respect to target position and the optimal number of laser shots for carrying out the experiments were investigated. The deposition rate was measured with varying laser wavelength and laser fluence. The angular distribution of the ablated material was measured for silver as well. A theoretical model based on the thermal properties of laser interaction with metals was applied in the initial phase of ablation. For the non-thermal processes governing laser interaction with the ablated plasma plume, a model developed by Phipps and Dreyfus was used to interpret the results. Laser ablation measurements of water-ice were carried using a Nitrogen laser. Attempts were made to measure the deposition rate for various the laser wavelengths and energies. (au) 8 tabs., 49 ills., 77 refs.

  6. Phase behavior of charged colloids : many-body effects, charge renormalization and charge regulation

    NARCIS (Netherlands)

    Zoetekouw, Bastiaan

    2006-01-01

    The main topic of this thesis is Poisson–Boltzmann theory for suspensions of charged colloids in two of its approximations: cell-type approximations that explicitly take into account non-linear effects near the colloidal surfaces, such as charge renormalization, at the expense of neglecting any

  7. Charge Injection, Charge Trapping and Charge Transfer in Quantum-Dot Solids

    NARCIS (Netherlands)

    Boehme, S.C.

    2015-01-01

    This study reports on fundamental processes in Quantum-Dot Solids, after light absorption. Transient Absorption and Time-resolved Photoluminescence spectrocopy reveal the dynamics of charge transfer and charge trapping processes. Typically, both occur on a picosecond time scale and compete with each

  8. Simulation of bipolar charge transport in nanocomposite polymer films

    Science.gov (United States)

    Lean, Meng H.; Chu, Wei-Ping L.

    2015-03-01

    This paper describes 3D particle-in-cell simulation of bipolar charge injection and transport through nanocomposite film comprised of ferroelectric ceramic nanofillers in an amorphous polymer matrix. The classical electrical double layer (EDL) model for a monopolar core is extended (eEDL) to represent the nanofiller by replacing it with a dipolar core. Charge injection at the electrodes assumes metal-polymer Schottky emission at low to moderate fields and Fowler-Nordheim tunneling at high fields. Injected particles migrate via field-dependent Poole-Frenkel mobility and recombine with Monte Carlo selection. The simulation algorithm uses a boundary integral equation method for solution of the Poisson equation coupled with a second-order predictor-corrector scheme for robust time integration of the equations of motion. The stability criterion of the explicit algorithm conforms to the Courant-Friedrichs-Levy limit assuring robust and rapid convergence. The model is capable of simulating a wide dynamic range spanning leakage current to pre-breakdown. Simulation results for BaTiO3 nanofiller in amorphous polymer matrix indicate that charge transport behavior depend on nanoparticle polarization with anti-parallel orientation showing the highest leakage conduction and therefore lowest level of charge trapping in the interaction zone. Charge recombination is also highest, at the cost of reduced leakage conduction charge. The eEDL model predicts the meandering pathways of charge particle trajectories.

  9. Measurements of aerosol charging states in Helsinki, Finland

    Directory of Open Access Journals (Sweden)

    S. Gagné

    2011-05-01

    Full Text Available The charging state of aerosol populations was measured with an Ion-DMPS in Helsinki, Finland between December 2008 and February 2010. Based on the charging states, we calculated the ion-induced nucleation fraction to be around 0.8 % ± 0.9 %. We review the role of ion-induced nucleation and propose different explanations for a low ion-induced nucleation participation in urban areas. We present a new method to retrieve the average charging state for an event, and a given size. We also use a new theoretical framework that allows for different concentrations of small cluster ions for different polarities (polarity asymmetry. We extrapolate the ion-induced fraction using polarity symmetry and asymmetry. Finally, a method to calculate the growth rates from the variation of the charging state as a function of the particle diameter using polarity symmetry and asymmetry is presented and used on a selection of new particle formation events.

  10. The charge spectrum of positive ions in a hydrogen aurora

    Science.gov (United States)

    Lynch, J.; Pulliam, D.; Leach, R.; Scherb, F.

    1976-01-01

    An auroral ion charge spectrometer was flown into a hydrogen aurora on a Javelin sounding rocket launched from Churchill, Manitoba. The instrument contained an electrostatic analyzer which selected particles with incident energy per unit charge up to 20 keV/charge and an 80-kV power supply which accelerated these ions onto an array of solid state detectors. Ions tentatively identified as H(+), He(+2), and O(+) were detected from 225 to 820 km in altitude. The experiment did not discriminate between H(+) and He(+), or between O(+), N(+), and C(+). Upper limits of highly charged heavy ion abundances have been set at 20% of the He(+2) and 0.15% of the H(+). It is concluded that both terrestrial and solar wind sources play significant roles in auroral ion precipitation.

  11. Electrokinetic inversion of ion screening charges in nano-channels

    CERN Document Server

    Zhu, Xin; Ni, Sheng; Zhang, Xingye; Liu, Yang

    2016-01-01

    This work studies a counter-intuitive but basic process of ionic screening in nano-fluidic channels. Numerical simulations and perturbation analysis reveal that, under significant electrokinetic transport, the ion screening charges can be locally inverted in the channels: their charge sign becomes the same as that of the channel surface charges. The process is identified to originate from the coupling of longitudinal transport and junction electrostatics. This finding may revise the common understanding of ionic screening in nano-channels and indicates that their ion selectivity can be locally changed by transport. Furthermore, the charge inversion process results in a body force torque on channel fluids, which is a possible mechanism for vortex generation in the channels.

  12. The charge spectrum of positive ions in a hydrogen aurora

    Science.gov (United States)

    Lynch, J.; Pulliam, D.; Leach, R.; Scherb, F.

    1976-01-01

    An auroral ion charge spectrometer was flown into a hydrogen aurora on a Javelin sounding rocket launched from Churchill, Manitoba. The instrument contained an electrostatic analyzer which selected particles with incident energy per unit charge up to 20 keV/charge and an 80-kV power supply which accelerated these ions onto an array of solid state detectors. Ions tentatively identified as H(+), He(+2), and O(+) were detected from 225 to 820 km in altitude. The experiment did not discriminate between H(+) and He(+), or between O(+), N(+), and C(+). Upper limits of highly charged heavy ion abundances have been set at 20% of the He(+2) and 0.15% of the H(+). It is concluded that both terrestrial and solar wind sources play significant roles in auroral ion precipitation.

  13. When Charged Black Holes Merge

    Science.gov (United States)

    Kohler, Susanna

    2016-08-01

    Most theoretical models assume that black holes arent charged. But a new study shows that mergers of charged black holes could explain a variety of astrophysical phenomena, from fast radio bursts to gamma-ray bursts.No HairThe black hole no hair theorem states that all black holes can be described by just three things: their mass, their spin, and their charge. Masses and spins have been observed and measured, but weve never measured the charge of a black hole and its widely believed that real black holes dont actually have any charge.That said, weve also never shown that black holes dont have charge, or set any upper limits on the charge that they might have. So lets suppose, for a moment, that its possible for a black hole to be charged. How might that affect what we know about the merger of two black holes? A recent theoretical study by Bing Zhang (University of Nevada, Las Vegas) examines this question.Intensity profile of a fast radio burst, a sudden burst of radio emission that lasts only a few milliseconds. [Swinburne Astronomy Productions]Driving TransientsZhangs work envisions a pair of black holes in a binary system. He argues that if just one of the black holes carries charge possibly retained by a rotating magnetosphere then it may be possible for the system to produce an electromagnetic signal that could accompany gravitational waves, such as a fast radio burst or a gamma-ray burst!In Zhangs model, the inspiral of the two black holes generates a global magnetic dipole thats perpendicular to the plane of the binarys orbit. The magnetic flux increases rapidly as the separation between the black holes decreases, generating an increasingly powerful magnetic wind. This wind, in turn, can give rise to a fast radio burst or a gamma-ray burst, depending on the value of the black holes charge.Artists illustration of a short gamma-ray burst, thought to be caused by the merger of two compact objects. [ESO/A. Roquette]Zhang calculates lower limits on the charge

  14. Big break for charge symmetry

    CERN Document Server

    Miller, G A

    2003-01-01

    Two new experiments have detected charge-symmetry breaking, the mechanism responsible for protons and neutrons having different masses. Symmetry is a crucial concept in the theories that describe the subatomic world because it has an intimate connection with the laws of conservation. The theory of the strong interaction between quarks - quantum chromodynamics - is approximately invariant under what is called charge symmetry. In other words, if we swap an up quark for a down quark, then the strong interaction will look almost the same. This symmetry is related to the concept of sup i sospin sup , and is not the same as charge conjugation (in which a particle is replaced by its antiparticle). Charge symmetry is broken by the competition between two different effects. The first is the small difference in mass between up and down quarks, which is about 200 times less than the mass of the proton. The second is their different electric charges. The up quark has a charge of +2/3 in units of the proton charge, while ...

  15. Charge-pump voltage converter

    Science.gov (United States)

    Brainard, John P.; Christenson, Todd R.

    2009-11-03

    A charge-pump voltage converter for converting a low voltage provided by a low-voltage source to a higher voltage. Charge is inductively generated on a transfer rotor electrode during its transit past an inductor stator electrode and subsequently transferred by the rotating rotor to a collector stator electrode for storage or use. Repetition of the charge transfer process leads to a build-up of voltage on a charge-receiving device. Connection of multiple charge-pump voltage converters in series can generate higher voltages, and connection of multiple charge-pump voltage converters in parallel can generate higher currents. Microelectromechanical (MEMS) embodiments of this invention provide a small and compact high-voltage (several hundred V) voltage source starting with a few-V initial voltage source. The microscale size of many embodiments of this invention make it ideally suited for MEMS- and other micro-applications where integration of the voltage or charge source in a small package is highly desirable.

  16. Analyzing Affect of Image Charge in Space Charge Effect

    Institute of Scientific and Technical Information of China (English)

    ZhangXueying; XuHushan; JiaFei; LiWenfei

    2003-01-01

    There is an increasing requirement of high injection current and highly charged ion beams for accelerators at many laboratories, such as CERN, GSI, GANIL and IMP, with the development of super-conducting ECR source in recent.years. In this case, the space charge effect becomes a major concern when the beam current is as high as tens of mA. In fact, the faradic field induced by the image charges will be come into the metallic surfaces while the beams are transported in a vacuum tube or in between two plates. In order to ensure studying the space charge effect in reason, it is necessary to investigate the effect from such a field.

  17. Classification of solar cells according to mechanisms of charge separation and charge collection.

    Science.gov (United States)

    Kirchartz, Thomas; Bisquert, Juan; Mora-Sero, Ivan; Garcia-Belmonte, Germà

    2015-02-14

    In the last decade, photovoltaics (PV) has experienced an important transformation. Traditional solar cells formed by compact semiconductor layers have been joined by new kinds of cells that are constituted by a complex mixture of organic, inorganic and solid or liquid electrolyte materials, and rely on charge separation at the nanoscale. Recently, metal organic halide perovskites have appeared in the photovoltaic landscape showing large conversion efficiencies, and they may share characteristics of the two former types. In this paper we provide a general description of the photovoltaic mechanisms of the single absorber solar cell types, combining all-inorganic, hybrid and organic cells into a single framework. The operation of the solar cell relies on a number of internal processes that exploit internal charge separation and overall charge collection minimizing recombination. There are two main effects to achieve the required efficiency, first to exploit kinetics at interfaces, favouring the required forward process, and second to take advantage of internal electrical fields caused by a built-in voltage and by the distribution of photogenerated charges. These principles represented by selective contacts, interfaces and the main energy diagram, form a solid base for the discussion of the operation of future types of solar cells. Additional effects based on ferroelectric polarization and ionic drift provide interesting prospects for investigating new PV effects mainly in the perovskite materials.

  18. Charge density waves in solids

    CERN Document Server

    Gor'kov, LP

    2012-01-01

    The latest addition to this series covers a field which is commonly referred to as charge density wave dynamics.The most thoroughly investigated materials are inorganic linear chain compounds with highly anisotropic electronic properties. The volume opens with an examination of their structural properties and the essential features which allow charge density waves to develop.The behaviour of the charge density waves, where interesting phenomena are observed, is treated both from a theoretical and an experimental standpoint. The role of impurities in statics and dynamics is considered and an

  19. Rewritable artificial magnetic charge ice

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y. -L.; Xiao, Z. -L.; Snezhko, A.; Xu, J.; Ocola, L. E.; Divan, R.; Pearson, J. E.; Crabtree, G. W.; Kwok, W. -K.

    2016-05-19

    Artificial ices enable the study of geometrical frustration by design and through direct observation. However, it has proven difficult to achieve tailored long-range ordering of their diverse configurations, limiting both fundamental and applied research directions. We designed an artificial spin structure that produces a magnetic charge ice with tunable long-range ordering of eight different configurations. We also developed a technique to precisely manipulate the local magnetic charge states and demonstrate write-read-erase multifunctionality at room temperature. This globally reconfigurable and locally writable magnetic charge ice could provide a setting for designing magnetic monopole defects, tailoring magnonics, and controlling the properties of other two-dimensional materials.

  20. Effect of Zn Adsorption on Charge of Variable Charge Soils

    Institute of Scientific and Technical Information of China (English)

    SUNHAN-YUAN

    1993-01-01

    The variation in appa rent carge of two typical variable charge soils resulting from Zn adsorption were studied by KCl saturation and NH4NO3 replacement methods.Results showed that zinc were adsorbed specifically to those sites with negative charge.As in different pH ranges,the percantages of specific and electrostatic adsorptions of zine and the mechanisms of specific adsorption were different,the effects of Zn adsorption on apparent charge were varied and could be characterized as:when 1 mmol Zn2+ was adsorbed,a change about 1 mmol in the apparent charge was observed in the low pH range(1),1.4 to 1.5mmol in the moderate pH range(II) and 0.55 to 0.6mmol in the high pH range (III).These experimental data,in terms of soil charge,proved once more author's conclusion in the preceding paper(Sun,1993) that in accordance with the behaviors of Zn adsorption by the variable charge soils in relation to pH,three pH ranges with different adsorption mechanisms were delineated;that is,in Range I,specific adsorption was the predominant mechanism,in Ranges II and III,specific and electrostatic adsorptions co-existed,but their specific adsorption mechanisms were not identical.

  1. Particle Catcher Using Induced-Charge Electroosmosis

    Science.gov (United States)

    Sugioka, Hideyuki

    2017-01-01

    Finding an innovative separation mechanism is a central task in future microfluidic systems. We propose a size-controllable microfluidic catching device that has a face-to-face structure consisting of elastic beams that change the acceptable particle size dynamically by hydrodynamic force due to induced charge electroosmosis (ICEO) in water and numerically examine the novel separation mechanism consisting of catching and releasing motions with size selectivity. By an implicit strongly coupled simulation technique between a fluid and an elastic structure based on the boundary element method, along with the thin double-layer approximation, we find that the catching device works effectively at low applied voltages in a realistic microfluidic channel and shows a wide range dynamic size selectivity. Furthermore, by modeling the ICEO phenomena with elastic motion, we successfully explain the acceptable particle size of the catching device. We believe that our proposed device will contribute to realizing innovative microfluidic systems in the future.

  2. Charge Transport in one dimension

    CERN Document Server

    Holcombe, S R

    2010-01-01

    We consider charge transport in nanopores where the dielectric constant inside the nanopore is much greater than in the surrounding material, so that the flux of the electric fields due to the charges is almost entirely confined to the nanopore. That means that we may model the electric fields due to charge densities in the nanopore in terms of average properties across the nanopore as solutions of one dimensional Poisson equations. We develop basic equations for an M component system using equations of continuity to relate concentrations to currents, and flux equations relating currents to concentration gradients and conductivities. We then derive simplified scaled versions of the equations. We develop exact solutions for the one component case in a variety of boundary conditions using a Hopf-Cole transformation, Fourier series, and periodic solutions of the Burgers equation. These are compared with a simpler model in which the scaled diffusivity is zero so that all charge motion is driven by the electric fi...

  3. Measurements of W Charge Asymmetry

    Energy Technology Data Exchange (ETDEWEB)

    Holzbauer, J. L. [Mississippi U.

    2015-10-06

    We discuss W boson and lepton charge asymmetry measurements from W decays in the electron channel, which were made using 9.7 fb$^{-1}$ of RunII data collected by the D0 detector at the Fermilab Tevatron Collider. The electron charge asymmetry is presented as a function of pseudo-rapidity out to |$\\eta$| $\\le$ 3.2, in five symmetric and asymmetric kinematic bins of electron transverse momentum and the missing transverse energy of the event. We also give the W charge asymmetry as a function of W boson rapidity. The asymmetries are compared with next-to-leading order perturbative quantum chromodynamics calculations. These charge asymmetry measurements will allow more accurate determinations of the proton parton distribution functions and are the most precise to date.

  4. Induced-charge Electrokinetic Phenomena

    CERN Document Server

    Bazant, M Z; Bazant, Martin Z.; Squires, Todd M.

    2003-01-01

    Motivated by the recent discovery of AC electro-osmosis near micro-electrodes, we predict a broad class of nonlinear electrokinetic phenomena involving induced interfacial charge. By considering various polarizable objects (metals or dielectrics) in DC and AC applied fields, we develop a simple physical picture of `induced-charge electro-osmosis' (ICEO), the fluid slip at a surface due to an electric field acting on the diffuse charge it induces. We also discuss `induced-charge electrophoresis' (ICEP), the analogous motion of a freely-suspended polarizable particle. Both differ significantly from their classical linear counterparts. We present a mathematical theory of ICEO flows in the weakly nonlinear limit of thin double layers. As an example, we calculate the time-dependent ICEO slip around a metallic sphere with a thin dielectric coating in a suddenly-applied DC field. We briefly discuss possible applications of ICEO to microfluidics and of ICEP to colloidal manipulation.

  5. Organic Text Authors Charge Plagiarism.

    Science.gov (United States)

    Chemical and Engineering News, 1979

    1979-01-01

    Reports on the recent controversy involving two organic chemistry textbooks. The charge of plagiarism and the court litigations are the object of interest in the chemical community since many prominant scientists are planned as witnesses. (SA)

  6. Screening Effect in Charge Qubit

    Institute of Scientific and Technical Information of China (English)

    HUA Ming; XIAO Xiao; GAO Yi-Bo

    2011-01-01

    We study the influence of screening effect on quantum decoherence for charge qubit and the process of quantum information storage. When the flux produced by the circulating current in SQUID loop is considered, screening effect is formally characterized by a LC resonator. Using large-detuning condition and Fr(o)hlich transformation in the qubit-cavity-resonator system, we calculate the decoherence factor for charge qubit and the effective qubit-cavity Hamiltonian. The decoherence factor owns a factorized structure, it shows that screening effect is a resource of decoherence for charge qubit. The effective Hamiltonian shows that the screening effect results in a frequency shift for charge qubit and a modified qubit-cavity coupling constant induced by a LC resonator.

  7. BRST charge for nonlinear algebras

    CERN Document Server

    Buchbinder, I L

    2007-01-01

    We study the construction of the classical nilpotent canonical BRST charge for the nonlinear gauge algebras where a commutator (in terms of Poisson brackets) of the constraints is a finite order polynomial of the constraints.

  8. Quantum physics: Destruction of discrete charge

    Science.gov (United States)

    Nazarov, Yuli V.

    2016-08-01

    Electric charge is quantized in units of the electron's charge. An experiment explores the suppression of charge quantization caused by quantum fluctuations and supports a long-standing theory that explains this behaviour. See Letter p.58

  9. Charged-Lepton Flavour Physics

    OpenAIRE

    Hoecker, Andreas

    2012-01-01

    This writeup of a talk at the 2011 Lepton-Photon symposium in Mumbai, India, summarises recent results in the charged-lepton flavour sector. I review searches for charged-lepton flavour violation, lepton electric dipole moments and flavour-conserving CP violation. I also discuss recent progress in tau-lepton physics and in the Standard Model prediction of the muon anomalous magnetic moment.

  10. Thermophoresis of charged colloidal particles.

    Science.gov (United States)

    Fayolle, Sébastien; Bickel, Thomas; Würger, Alois

    2008-04-01

    Thermally induced particle flow in a charged colloidal suspension is studied in a fluid-mechanical approach. The force density acting on the charged boundary layer is derived in detail. From Stokes' equation with no-slip boundary conditions at the particle surface, we obtain the particle drift velocity and the thermophoretic transport coefficients. The results are discussed in view of previous work and available experimental data.

  11. Thermophoresis of charged colloidal particles

    OpenAIRE

    Fayolle, Sébastien; Bickel, Thomas; Würger, Alois

    2008-01-01

    International audience; Thermally induced particle flow in a charged colloidal suspension is studied in a fluid-mechanical approach. The force density acting on the charged boundary layer is derived in detail. From Stokes' equation with no-slip boundary conditions at the particle surface, we obtain the particle drift velocity and the thermophoretic transport coefficients. The results are discussed in view of previous work and available experimental data.

  12. A note on charged interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Luo Huaqiang [Courant Institute of Mathematical Sciences, New York University, New York, NY 10012 (United States); Yu, M Y [Institute for Theoretical Physics I, Ruhr-University, D-44780 Bochum (Germany)

    2006-12-15

    A condition associated with the plasma boundary or other charged interface is reviewed. It is pointed out that in comparing theories and simulations of such interfaces, in order to avoid conflicting results it should be ascertained that the systems under consideration are thermodynamically equivalent. For the plasma-wall interface in equilibrium, the rate of change of the surface-charge density with respect to the surface potential must be positive.

  13. Multizone Artillery Propelling Charge Studies

    Science.gov (United States)

    1983-05-01

    PROJECT, TASK AREA 4 WORK UNIT NUMBERS IL162618AH80 11. CONTROLLING OFFICE NAME AND ADDRESS US Army Armament Research & Development Command...are affected by the many interrelated components comprising the charge. We have identified areas of concern for bagged multizone charges; studies...B. Brodman DRDAP-LCB-I, D. Spring DRDAR-LCE, R. Walker DRDAR-LCU-CT E. Barrleres R. Davitt DRDAR-CLU-CV C.Mandala E. Moore DRDAR-LCM-E S

  14. Metallic charge stripes in cuprates

    Energy Technology Data Exchange (ETDEWEB)

    Tranquada, J.M

    2004-08-01

    Some recent evidence for the existence of dynamic, metallic stripes in the 214 family of cuprates is reviewed. The mechanism of stripe pinning is considered, and changes in the charge density within stripes between the pinned and dynamic phases is discussed. From a purely experimental perspective, dynamic charge stripes are fully compatible with nodal 'quasiparticles' and other electronic properties common to all superconducting cuprates.

  15. Metallic charge stripes in cuprates

    Science.gov (United States)

    Tranquada, J. M.

    2004-08-01

    Some recent evidence for the existence of dynamic, metallic stripes in the 214 family of cuprates is reviewed. The mechanism of stripe pinning is considered, and changes in the charge density within stripes between the pinned and dynamic phases is discussed. From a purely experimental perspective, dynamic charge stripes are fully compatible with nodal “quasiparticles” and other electronic properties common to all superconducting cuprates.

  16. Charged-lepton flavour physics

    Indian Academy of Sciences (India)

    Andreas Hoecker

    2012-11-01

    This write-up on a talk at the 2011 Lepton–Photon symposium in Mumbai, India, summarizes recent results in the charged-lepton flavour sector. Searches for charged-lepton flavour violation, lepton electric dipole moments and flavour-conserving CP violation are reviewed here. Recent progress in -lepton physics and in the Standard Model prediction of the muon anomalous magnetic moment is also discussed.

  17. Fingerprints of charge exchange between He2+ and water molecules

    NARCIS (Netherlands)

    Bodewits, D.; Tielens, A.G.G.M.; Morgenstern, R.W.H.; Hoekstra, R.A.

    We have measured state selective cross sections for single and double charge exchange of He2+ and water molecules at velocities of 500-1000 km/s. The cross sections for single electron capture into the HeII(2p) state are much larger than those for double electron capture into the HeI(1s2p) state.

  18. Study of Two Digital Charge-Coupled Devices

    Science.gov (United States)

    Wilson, D. D.; Young, V. F.

    1982-01-01

    Recent report describes reliability study of two charge-coupled-device (CCD) shift registers. Major objective of study was to establish methodology for selecting, testing, screening, derating and applying CCD's. Includes a discussion of CCD structures and operating principles. Characteristics of SCCD and BCCD types are compared.

  19. Fractional Effective Charges and Misner-Wheeler Charge without Charge Effect in Metamaterials

    Directory of Open Access Journals (Sweden)

    Igor Smolyaninov

    2016-07-01

    Full Text Available Transformation optics enables engineering of the effective topology and dimensionality of the optical space in metamaterials. Nonlinear optics of such metamaterials may mimic Kaluza-Klein theories having one or more kinds of effective charges. As a result, novel photon blockade devices may be realized. Here we demonstrate that an electromagnetic wormhole may be designed, which connects two points of such an optical space and changes its effective topological connectivity. Electromagnetic field configurations, which exhibit fractional effective charges, appear as a result of such topology change. Moreover, such effects as Misner-Wheeler “charge without charge” may be replicated.

  20. Jet charge at the LHC.

    Science.gov (United States)

    Krohn, David; Schwartz, Matthew D; Lin, Tongyan; Waalewijn, Wouter J

    2013-05-24

    Knowing the charge of the parton initiating a light-quark jet could be extremely useful both for testing aspects of the standard model and for characterizing potential beyond-the-standard-model signals. We show that despite the complications of hadronization and out-of-jet radiation such as pileup, a weighted sum of the charges of a jet's constituents can be used at the LHC to distinguish among jets with different charges. Potential applications include measuring electroweak quantum numbers of hadronically decaying resonances or supersymmetric particles, as well as standard model tests, such as jet charge in dijet events or in hadronically decaying W bosons in tt[over ¯] events. We develop a systematically improvable method to calculate moments of these charge distributions by combining multihadron fragmentation functions with perturbative jet functions and pertubative evolution equations. We show that the dependence on energy and jet size for the average and width of the jet charge can be calculated despite the large experimental uncertainty on fragmentation functions. These calculations can provide a validation tool for data independent of Monte Carlo fragmentation models.

  1. Electroelasticity of Charged Black Branes

    CERN Document Server

    Armas, Jay; Obers, Niels A

    2013-01-01

    We present the first order corrected dynamics of fluid branes carrying higher-form charge by obtaining the general form of their equations of motion to pole-dipole order. Assuming linear response theory, we characterize the corresponding effective theory of stationary bent charged (an)isotropic fluid branes in terms of two sets of response coefficients, the Young modulus and the piezoelectric moduli. We subsequently find large classes of examples in gravity of this effective theory, by constructing stationary strained charged black brane solutions to first order in a derivative expansion. Using solution generating techniques and bent neutral black branes as a seed solution, we obtain a class of charged black brane geometries carrying smeared Maxwell charge in Einstein-Maxwell-dilaton gravity. In the specific case of ten-dimensional space-time we furthermore use T-duality to generate bent black branes with higher-form charge, including smeared D-branes of type II string theory. By subsequently measuring the be...

  2. Solar Charged Stand Alone Inverter

    Directory of Open Access Journals (Sweden)

    M.Vasugi

    2014-07-01

    Full Text Available This paper deals with solar powered stand alone inverter which converts the variable dc output of a photovoltaic solar panel into ac that can be fed to loads. Stand alone inverters are used in systems where the inverter get its energy from batteries charged by photo voltaic arrays. A charge controller limits the rate at which electric current is added to or drawn from electric batteries. This charge discharge controller is needed to prevent the battery from being overcharged or discharged thus prolonging its life. The charge/discharge control is necessary in order to achieve safety and increase the capacity of the battery. The project has been tested according its operational purposes. Maximum power rating of the experimented solar charge controller is 100W according battery capacities. Cost effective solar charge controller has been designed and implemented to have efficient system and much longer battery lifetime. The dc output is given to inverter and then it is supplied to loads. This method is very cheap and cost effective.

  3. Preparation of Composite Charge-mosaic Hollow Fiber Membrane by Interfacial Polymerization

    Institute of Scientific and Technical Information of China (English)

    Hao Qin ZHANG; Jin Dun LIU

    2004-01-01

    The preparation of composite charge-mosaic membrane included spinning of hollow fiber as the supporting membrane, preparing a selective layer on the inside surface of the fiber by interfacial polymerization. The charge-mosaic membranes show a high salt permeability while retaining sucrose. The charge-mosaic membrane can be effectively used to separate multivalent salts with organic matter of molecular weight great than 300 g/mol in industry.

  4. Effect of hydrogen charging on the mechanical properties of medium strength aluminium alloys 2091 and 2014

    DEFF Research Database (Denmark)

    Bandopadhyay, A.; Ambat, Rajan; Dwarakadasa, E.S.

    1992-01-01

    Cathodic hydrogen charging in 3.5% NaCl solution altered the mechanical properties of 2091-T351 (Al-Cu-Li-Mg-Zr) determined by a slow (10(-3)/s) strain rate tensile testing technique. UTS and YS decreased in the caw of 2091-T351 and 2014-T6(Al-Cu-Mn-Si-Mg) with increase in charging current density...

  5. Nonsense mutations and altered splice-site selection

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, H.C. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States)

    1997-03-01

    The invited editorial by Maquat, regarding defects in RNA splicing and the consequence of shortened translational reading frames, provided a balanced and comprehensive review of the topic. We believe, however, that our work describing the nonsense codon-mediated skipping of fibrillin-1 exon 51 was interpreted in a manner that is not fully supported by our data. 6 refs.

  6. Synthesis and properties of differently charged chemiluminescent acridinium ester labels.

    Science.gov (United States)

    Natrajan, Anand; Sharpe, David

    2013-02-14

    Chemiluminescent acridinium dimethylphenyl esters containing N-sulfopropyl groups in the acridinium ring are highly sensitive, hydrophilic labels that are used in automated immunoassays for clinical diagnostics. Light emission from these labels is triggered with alkaline peroxide in the presence of a cationic surfactant. At physiological pH, N-sulfopropyl acridinium esters exist as water adducts that are commonly referred to as pseudobases. Pseudobase formation, which results from addition of water to the zwitterionic N-sulfopropyl acridinium ring, neutralizes the positive charge on the acridinium nitrogen and imparts a net negative charge to the label due to the sulfonate moiety. As a consequence, N-sulfopropyl acridinium ester conjugates of small molecule haptens as well as large molecules such as proteins gain negative charges at neutral pH. In the current study, we describe the synthesis and properties of two new hydrophilic acridinium dimethylphenyl ester labels where the net charge in the labels was altered. In one label, the structure of the hydrophilic N-alkyl group attached to the acridinium ring was changed so that the pseudobase of the label contains no net charge. In the second acridinium ester, two additional negative charges in the form of sulfopropyl groups were added to the acridinium ring to make this label's pseudobase strongly anionic. Chemiluminescence measurements of these labels, as well as their conjugates of an antibody with a neutral pI, indicate that acridinium ester charge while having a modest effect on emission kinetics has little influence on light output. However, our results demonstrate that acridinium ester charge can affect protein pI, apparent chemiluminescence stability and non-specific binding of protein conjugates to microparticles. These results emphasize the need for careful consideration of acridinium ester charge in order to optimize reagent stability and performance in immunoassays. In the current study, we observed that

  7. Local Time-Dependent Charging in a Perovskite Solar Cell.

    Science.gov (United States)

    Bergmann, Victor W; Guo, Yunlong; Tanaka, Hideyuki; Hermes, Ilka M; Li, Dan; Klasen, Alexander; Bretschneider, Simon A; Nakamura, Eiichi; Berger, Rüdiger; Weber, Stefan A L

    2016-08-03

    Efficient charge extraction within solar cells explicitly depends on the optimization of the internal interfaces. Potential barriers, unbalanced charge extraction, and interfacial trap states can prevent cells from reaching high power conversion efficiencies. In the case of perovskite solar cells, slow processes happening on time scales of seconds cause hysteresis in the current-voltage characteristics. In this work, we localized and investigated these slow processes using frequency-modulation Kelvin probe force microscopy (FM-KPFM) on cross sections of planar methylammonium lead iodide (MAPI) perovskite solar cells. FM-KPFM can map the charge density distribution and its dynamics at internal interfaces. Upon illumination, space charge layers formed at the interfaces of the selective contacts with the MAPI layer within several seconds. We observed distinct differences in the charging dynamics at the interfaces of MAPI with adjacent layers. Our results indicate that more than one process is involved in hysteresis. This finding is in agreement with recent simulation studies claiming that a combination of ion migration and interfacial trap states causes the hysteresis in perovskite solar cells. Such differences in the charging rates at different interfaces cannot be separated by conventional device measurements.

  8. Problems in point charge electrodynamics

    CERN Document Server

    Ferris, Michael R

    2013-01-01

    (Shortened due to character limit) This thesis consists of two parts. In part I we consider a discrepancy in the derivation of the electromagnetic self force for a point charge. In the point charge framework the self force can be defined as an integral of the Lienard-Wiechert stress 3-forms over a suitably defined worldtube. We show the Schott term may be obtained using a null displacement vector to define the worldtube providing certain conditions are realized. Part II comprises an investigation into a problem in accelerator physics. In a high energy accelerator the cross-section of the beampipe is not continuous and there exist geometric discontinuities such as collimators and cavities. When a relativistic bunch of particles passes such a discontinuity the field generated by a leading charge can interact with the wall and consequently affect the motion of trailing charges. The fields acting on the trailing charges are known as (geometric) wakefields. We model a bunch of particles as a one dimensional contin...

  9. Space Charge Modulated Electrical Breakdown

    Science.gov (United States)

    Li, Shengtao; Zhu, Yuanwei; Min, Daomin; Chen, George

    2016-09-01

    Electrical breakdown is one of the most important physical phenomena in electrical and electronic engineering. Since the early 20th century, many theories and models of electrical breakdown have been proposed, but the origin of one key issue, that the explanation for dc breakdown strength being twice or higher than ac breakdown strength in insulating materials, remains unclear. Here, by employing a bipolar charge transport model, we investigate the space charge dynamics in both dc and ac breakdown processes. We demonstrate the differences in charge accumulations under both dc and ac stresses and estimate the breakdown strength, which is modulated by the electric field distortion induced by space charge. It is concluded that dc breakdown initializes in the bulk whereas ac breakdown initializes in the vicinity of the sample-electrode interface. Compared with dc breakdown, the lower breakdown strength under ac stress and the decreasing breakdown strength with an increase in applied frequency, are both attributed to the electric field distortion induced by space charges located in the vicinity of the electrodes.

  10. A Study on Wireless Charging for Prolonging the Lifetime of Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Weijian Tu

    2017-07-01

    Full Text Available Wireless charging is an important issue in wireless sensor networks, since it can provide an emerging and effective solution in the absence of other power supplies. The state-of-the-art methods employ a mobile car and a predefined moving path to charge the sensor nodes in the network. Previous studies only consider a factor of the network (i.e., residual energy of sensor node as a constraint to design the wireless charging strategy. However, other factors, such as the travelled distance of the mobile car, can also affect the effectiveness of wireless charging strategy. In this work, we study wireless charging strategy based on the analysis of a combination of two factors, including the residual energy of sensor nodes and the travelled distance of the charging car. Firstly, we theoretically analyze the limited size of the sensor network to match the capability of a charging car. Then, the networked factors are selected as the weights of traveling salesman problem (TSP to design the moving path of the charging car. Thirdly, the charging time of each sensor node is computed based on the linear programming problem for the charging car. Finally, a charging period for the network is studied. The experimental results show that the proposed approach can significantly maximize the lifetime of the wireless sensor network.

  11. A Study on Wireless Charging for Prolonging the Lifetime of Wireless Sensor Networks.

    Science.gov (United States)

    Tu, Weijian; Xu, Xianghua; Ye, Tingcong; Cheng, Zongmao

    2017-07-04

    Wireless charging is an important issue in wireless sensor networks, since it can provide an emerging and effective solution in the absence of other power supplies. The state-of-the-art methods employ a mobile car and a predefined moving path to charge the sensor nodes in the network. Previous studies only consider a factor of the network (i.e., residual energy of sensor node) as a constraint to design the wireless charging strategy. However, other factors, such as the travelled distance of the mobile car, can also affect the effectiveness of wireless charging strategy. In this work, we study wireless charging strategy based on the analysis of a combination of two factors, including the residual energy of sensor nodes and the travelled distance of the charging car. Firstly, we theoretically analyze the limited size of the sensor network to match the capability of a charging car. Then, the networked factors are selected as the weights of traveling salesman problem (TSP) to design the moving path of the charging car. Thirdly, the charging time of each sensor node is computed based on the linear programming problem for the charging car. Finally, a charging period for the network is studied. The experimental results show that the proposed approach can significantly maximize the lifetime of the wireless sensor network.

  12. Surface charge and hydrodynamic coefficient measurements of Bacillus subtilis spore by optical tweezers.

    Science.gov (United States)

    Pesce, Giuseppe; Rusciano, Giulia; Sasso, Antonio; Isticato, Rachele; Sirec, Teja; Ricca, Ezio

    2014-04-01

    In this work we report on the simultaneous measurement of the hydrodynamic coefficient and the electric charge of single Bacillus subtilis spores. The latter has great importance in protein binding to spores and in the adhesion of spores onto surfaces. The charge and the hydrodynamic coefficient were measured by an accurate procedure based on the analysis of the motion of single spores confined by an optical trap. The technique has been validated using charged spherical polystyrene beads. The excellent agreement of our results with the expected values demonstrates the quality of our procedure. We measured the charge of spores of B. subtilis purified from a wild type strain and from two isogenic mutants characterized by an altered spore surface. Our technique is able to discriminate the three spore types used, by their charge and by their hydrodynamic coefficient which is related to the hydrophobic properties of the spore surface. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Charged Higgs Analysis in CMS

    CERN Document Server

    Eysermans, Jan

    2016-01-01

    In this talk an overview is given of the possible searches of the Charged Higgs Boson during run 2 of the LHC data taking period. The Charged Higgs boson emerges in several (minimal) Standard Model (SM) extensions such as the 2 Doublet Higgs Model, which predicts 5 physical Higgs bosons, consistent with the SM Higgs boson. Based on the main production and decay modes, the possible intermediate and final state particles are predicted for a Charged Higgs mass higher than the top quark mass ($m_{H^{\\pm}} > m_t$). In particular, the dominant H to tau nu and H to tb channels are discussed in more detail together with their associated background.

  14. Charged gravastars admitting conformal motion

    CERN Document Server

    Usmani, A A; Ray, Saibal; Nandi, K K; Kuhfittig, Peter K F; Rakib, Sk A; Hasan, Z

    2010-01-01

    We propose a new model of a {\\it gravastar} admitting conformal motion. While retaining the framework of the Mazur-Mottola model, the gravastar is assumed to be internally charged, with an exterior defined by a Reissner-Nordstr{\\"o}m rather than a Schwarzschild line element. The solutions obtained involve (i) the interior region, (ii) the shell, and (iii) the exterior region of the sphere. Of these three cases the first case is of primary interest since the total gravitational mass vanishes for vanishing charge and turns the total gravitational mass into an {\\it electromagnetic mass} under certain conditions. This suggests that the interior de Sitter vacuum of a charged gravastar is essentially an electromagnetic mass model that must generate the gravitational mass. We have also analyzed various other aspects such as the stress energy tensor in the thin shell and the entropy of the system.

  15. Charging transient in polyvinyl formal

    Indian Academy of Sciences (India)

    P K Khare; P L Jain; R K Pandey

    2001-08-01

    In the present paper charging and discharging transient currents in polyvinyl formal (PVF) were measured as a function of temperatures (40–80°C), poling fields (9.0 × 103–9.0 × 104 V/cm) and electrode combinations (Al–Al, Au–Al, Zn–Al, Bi–Al, Cu–Al and Ag–Al). The current–time characteristics have different values of slope lying between 0.42–0.56 and 1.42–1.63. The polarization is considered to be due to dipolar reorientation associated with structural motions and space charge relaxations due to trapping of injected charge carriers in energetically distributed traps.

  16. Genetic Alterations in Glioma

    Energy Technology Data Exchange (ETDEWEB)

    Bralten, Linda B. C.; French, Pim J., E-mail: p.french@erasmusmc.nl [Department of Neurology, Erasmus University Medical Center, Erasmus University Rotterdam, Dr Molewaterplein 50, 3000 CA, Rotterdam (Netherlands)

    2011-03-07

    Gliomas are the most common type of primary brain tumor and have a dismal prognosis. Understanding the genetic alterations that drive glioma formation and progression may help improve patient prognosis by identification of novel treatment targets. Recently, two major studies have performed in-depth mutation analysis of glioblastomas (the most common and aggressive subtype of glioma). This systematic approach revealed three major pathways that are affected in glioblastomas: The receptor tyrosine kinase signaling pathway, the TP53 pathway and the pRB pathway. Apart from frequent mutations in the IDH1/2 gene, much less is known about the causal genetic changes of grade II and III (anaplastic) gliomas. Exceptions include TP53 mutations and fusion genes involving the BRAF gene in astrocytic and pilocytic glioma subtypes, respectively. In this review, we provide an update on all common events involved in the initiation and/or progression across the different subtypes of glioma and provide future directions for research into the genetic changes.

  17. Music alters visual perception.

    Directory of Open Access Journals (Sweden)

    Jacob Jolij

    Full Text Available BACKGROUND: Visual perception is not a passive process: in order to efficiently process visual input, the brain actively uses previous knowledge (e.g., memory and expectations about what the world should look like. However, perception is not only influenced by previous knowledge. Especially the perception of emotional stimuli is influenced by the emotional state of the observer. In other words, how we perceive the world does not only depend on what we know of the world, but also by how we feel. In this study, we further investigated the relation between mood and perception. METHODS AND FINDINGS: We let observers do a difficult stimulus detection task, in which they had to detect schematic happy and sad faces embedded in noise. Mood was manipulated by means of music. We found that observers were more accurate in detecting faces congruent with their mood, corroborating earlier research. However, in trials in which no actual face was presented, observers made a significant number of false alarms. The content of these false alarms, or illusory percepts, was strongly influenced by the observers' mood. CONCLUSIONS: As illusory percepts are believed to reflect the content of internal representations that are employed by the brain during top-down processing of visual input, we conclude that top-down modulation of visual processing is not purely predictive in nature: mood, in this case manipulated by music, may also directly alter the way we perceive the world.

  18. Altered Perspectives: Immersive Environments

    Science.gov (United States)

    Shipman, J. S.; Webley, P. W.

    2016-12-01

    Immersive environments provide an exciting experiential technology to visualize the natural world. Given the increasing accessibility of 360o cameras and virtual reality headsets we are now able to visualize artistic principles and scientific concepts in a fully immersive environment. The technology has become popular for photographers as well as designers, industry, educational groups, and museums. Here we show a sci-art perspective on the use of optics and light in the capture and manipulation of 360o images and video of geologic phenomena and cultural heritage sites in Alaska, England, and France. Additionally, we will generate intentionally altered perspectives to lend a surrealistic quality to the landscapes. Locations include the Catacombs of Paris, the Palace of Versailles, and the Northern Lights over Fairbanks, Alaska. Some 360o view cameras now use small portable dual lens technology extending beyond the 180o fish eye lens previously used, providing better coverage and image quality. Virtual reality headsets range in level of sophistication and cost, with the most affordable versions using smart phones and Google Cardboard viewers. The equipment used in this presentation includes a Ricoh Theta S spherical imaging camera. Here we will demonstrate the use of 360o imaging with attendees being able to be part of the immersive environment and experience our locations as if they were visiting themselves.

  19. 76 FR 10233 - Schedule of Water Charges

    Science.gov (United States)

    2011-02-24

    ... COMMISSION 18 CFR Part 420 Schedule of Water Charges AGENCY: Delaware River Basin Commission. ACTION: Final...--Water Supply Charges. Accordingly, the Commission's water charging rates for consumptive use and non.... FOR FURTHER INFORMATION CONTACT: For questions about the water charging program, please contact...

  20. 47 CFR 69.124 - Interconnection charge.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Interconnection charge. 69.124 Section 69.124... Computation of Charges § 69.124 Interconnection charge. (a) Until December 31, 2001, local exchange carriers not subject to price cap regulation shall assess an interconnection charge expressed in dollars...

  1. Nanotribology of charged polymer brushes

    Science.gov (United States)

    Klein, Jacob

    Polymers at surfaces, whose modern understanding may be traced back to early work by Sam Edwards1, have become a paradigm for modification of surface properties, both as steric stabilizers and as remarkable boundary lubricants2. Charged polymer brushes are of particular interest, with both technological implications and especially biological relevance where most macromolecules are charged. In the context of biolubrication, relevant in areas from dry eye syndrome to osteoarthritis, charged polymer surface phases and their complexes with other macromolecules may play a central role. The hydration lubrication paradigm, where tenaciously-held yet fluid hydration shells surrounding ions or zwitterions serve as highly-efficient friction-reducing elements, has been invoked to understand the excellent lubrication provided both by ionized3 and by zwitterionic4 brushes. In this talk we describe recent advances in our understanding of the nanotribology of such charged brush systems. We consider interactions between charged end-grafted polymers, and how one may disentangle the steric from the electrostatic surface forces5. We examine the limits of lubrication by ionized brushes, both synthetic and of biological origins, and how highly-hydrated zwitterionic chains may provide extremely effective boundary lubrication6. Finally we describe how the lubrication of articular cartilage in the major joints, a tribosystem presenting some of the greatest challenges and opportunities, may be understood in terms of a supramolecular synergy between charged surface-attached polymers and zwitterionic groups7. Work supported by European Research Council (HydrationLube), Israel Science Foundation (ISF), Petroleum Research Fund of the American Chemical Society, ISF-NSF China Joint Program.

  2. Electric Charge in Interaction with Magnetically Charged Black Holes

    CERN Document Server

    Kim, J H

    2007-01-01

    We examine the angular momentum of an electric charge e placed at rest outside a dilaton black hole with magnetic charge Q. The electromagnetic angular momentum which is stored in the electromagnetic field outside the black hole shows several common features regardless of the dilaton coupling strength, though the dilaton black holes are drastically different in their spacetime structure depending on it. First, the electromagnetic angular momentum depends on the separation distance between the two objects and changes monotonically from eQ to 0 as the charge goes down from infinity to the horizon, if rotational effects of the black hole are discarded. Next, as the black hole approaches extremality, however, the electromagnetic angular momentum tends to be independent of the distance between the two objects. It is then precisely $eQ$ as in the electric charge and monopole system in flat spacetime. We discuss why these effects are exhibited and argue that the above features are to hold in widely generic settings ...

  3. Absolute Stability Limit for Relativistic Charged Spheres

    CERN Document Server

    Giuliani, Alessandro

    2007-01-01

    We find an exact solution for the stability limit of relativistic charged spheres for the case of constant gravitational mass density and constant charge density. We argue that this provides an absolute stability limit for any relativistic charged sphere in which the gravitational mass density decreases with radius and the charge density increases with radius. We then provide a cruder absolute stability limit that applies to any charged sphere with a spherically symmetric mass and charge distribution. We give numerical results for all cases. In addition, we discuss the example of a neutral sphere surrounded by a thin, charged shell.

  4. Scientist to appeal misconduct charge

    Science.gov (United States)

    Gwynne, Peter

    2008-08-01

    Lawyers for the "bubble-fusion" researcher Rusi Taleyarkhan have told Physics World that he will appeal over the findings of a panel that last month found him guilty of two charges of scientific misconduct. Taleyarkhan, a nuclear engineer at Purdue University in the US, was charged by a sixmember internal committee, which concluded that he had cited a paper by researchers in his own lab as if it were an independent confirmation of his alleged discovery of bubble fusion in 2002. The committee also found him guilty of adding the name of a student who had not contributed to that paper as an author.

  5. A charged spherically symmetric solution

    Indian Academy of Sciences (India)

    K Moodley; S D Maharaj; K S Govinder

    2003-09-01

    We find a solution of the Einstein–Maxwell system of field equations for a class of accelerating, expanding and shearing spherically symmetric metrics. This solution depends on a particular ansatz for the line element. The radial behaviour of the solution is fully specified while the temporal behaviour is given in terms of a quadrature. By setting the charge contribution to zero we regain an (uncharged) perfect fluid solution found previously with the equation of state =+ constant, which is a generalisation of a stiff equation of state. Our class of charged shearing solutions is characterised geometrically by a conformal Killing vector.

  6. Static Charge Development on Explosives .

    Directory of Open Access Journals (Sweden)

    K. Raha

    1991-01-01

    Full Text Available Static charge development character of some of the important explosive crystals have been predicted on the basis of their crystal class and symmetry. Among the important mechanism of charge development, the piezoelectric and pyroelectric characters have been considered. Ammonium trinitrate, ammonium nitrate, m-dinitro-benzene, trinitro-toluene, styphnic acid, beeta-lead styphnate, 4,4'dinitro-dipheny1, a-hexamethylenetetranitramine, nitroguanidine, picric acid, dimethylnitramine, a-lead azide and beeta-lead azide are pyroelectric in nature, whereas pentaerythritol tetranitrate, picryliodide, hexamethylenetranitramine, tetranitromethane and trinitroethane are piezoelectric in nature.

  7. Hydration of highly charged ions.

    Science.gov (United States)

    Hofer, Thomas S; Weiss, Alexander K H; Randolf, Bernhard R; Rode, Bernd M

    2011-08-01

    Based on a series of ab initio quantum mechanical charge field molecular dynamics (QMCF MD) simulations, the broad spectrum of structural and dynamical properties of hydrates of trivalent and tetravalent ions is presented, ranging from extreme inertness to immediate hydrolysis. Main group and transition metal ions representative for different parts of the periodic system are treated, as are 2 threefold negatively charged anions. The results show that simple predictions of the properties of the hydrates appear impossible and that an accurate quantum mechanical simulation in cooperation with sophisticated experimental investigations seems the only way to obtain conclusive results.

  8. Equilibrium configurations of tripolar charges

    CERN Document Server

    Yershov, V N

    2005-01-01

    It is shown that an ensemble of particles with tripolar (colour) charges will necessarily cohere in a hierarchy of structures, from simple clusters and strings to complex aggregates and cyclic molecule-like structures. The basic combinatoric rule remains essentially the same on different levels of the hierarchy, thus leading to a pattern of resemblance between different levels. The number of primitive charges in each structure is determined by the symmetry of the combined effective potential of this structure. The outlined scheme can serve as a framework for building a model of composite fundamental fermions.

  9. Electrooptical Detection of Charged Particles

    CERN Document Server

    Semertzidis, Y K; Kowalski, L A; Kraus, D E; Larsen, R; Lazarus, D M; Magurno, B; Nikas, D; Ozben, C; Srinivasan-Rao, T; Tsang, Thomas

    2000-01-01

    We have made the first observation of a charged particle beam by means of its electro-optical effect on the polarization of laser light in a LiNbO3 crystal. The modulation of the laser light during the passage of a pulsed electron beam was observed using a fast photodiode and a digital oscilloscope. The fastest rise time measured, 120 ps, was obtained in the single shot mode and was limited by the bandwidth of the oscilloscope and the associated electronics. This technology holds promise for detectors of greatly improved spatial and temporal resolution for single relativistic charged particles as well as particle beams.

  10. Cost-Effectiveness Comparison of Coupler Designs of Wireless Power Transfer for Electric Vehicle Dynamic Charging

    Directory of Open Access Journals (Sweden)

    Weitong Chen

    2016-11-01

    Full Text Available This paper presents a cost-effectiveness comparison of coupler designs for wireless power transfer (WPT, meant for electric vehicle (EV dynamic charging. The design comparison of three common types of couplers is first based on the raw material cost, output power, transfer efficiency, tolerance of horizontal offset, and flux density. Then, the optimal cost-effectiveness combination is selected for EV dynamic charging. The corresponding performances of the proposed charging system are compared and analyzed by both simulation and experimentation. The results verify the validity of the proposed dynamic charging system for EVs.

  11. Diagnostics of many-particle electronic states: non-stationary currents and residual charge dynamics

    Science.gov (United States)

    Maslova, N. S.; Mantsevich, V. N.; Arseyev, P. I.

    2017-01-01

    We propose the method for identifying many particle electronic states in the system of coupled quantum dots (impurities) with Coulomb correlations. We demonstrate that different electronic states can be distinguished by the complex analysis of localized charge dynamics and non-stationary characteristics. We show that localized charge time evolution strongly depends on the properties of initial state and analyze different time scales in charge kinetics for initially prepared singlet and triplet states. We reveal the conditions for existence of charge trapping effects governed by the selection rules for electron transitions between the states with different occupation numbers.

  12. Multiple-charge transfer and trapping in DNA dimers

    Science.gov (United States)

    Tornow, Sabine; Bulla, Ralf; Anders, Frithjof B.; Zwicknagl, Gertrud

    2010-11-01

    We investigate the charge transfer characteristics of one and two excess charges in a DNA base-pair dimer using a model Hamiltonian approach. The electron part comprises diagonal and off-diagonal Coulomb matrix elements such a correlated hopping and the bond-bond interaction, which were recently calculated by Starikov [E. B. Starikov, Philos. Mag. Lett. 83, 699 (2003)10.1080/0950083031000151374] for different DNA dimers. The electronic degrees of freedom are coupled to an ohmic or a superohmic bath serving as dissipative environment. We employ the numerical renormalization group method in the nuclear tunneling regime and compare the results to Marcus theory for the thermal activation regime. For realistic parameters, the rate that at least one charge is transferred from the donor to the acceptor in the subspace of two excess electrons significantly exceeds the rate in the single charge sector. Moreover, the dynamics is strongly influenced by the Coulomb matrix elements. We find sequential and pair transfer as well as a regime where both charges remain self-trapped. The transfer rate reaches its maximum when the difference of the on-site and intersite Coulomb matrix element is equal to the reorganization energy which is the case in a guanine/cytosine (GC)-dimer. Charge transfer is completely suppressed for two excess electrons in adenine/thymine (AT)-dimer in an ohmic bath and replaced by damped coherent electron-pair oscillations in a superohmic bath. A finite bond-bond interaction W alters the transfer rate: it increases as function of W when the effective Coulomb repulsion exceeds the reorganization energy (inverted regime) and decreases for smaller Coulomb repulsion.

  13. Amine reactivity with charged sulfuric acid clusters

    OpenAIRE

    Bzdek, B. R.; D. P. Ridge; Johnston, M. V.

    2011-01-01

    The distribution of charged species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid n...

  14. Charge Management Optimization for Future TOU Rates

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiucai; Markel, Tony

    2016-06-22

    The effectiveness of future time of use (TOU) rates to enable managed charging for providing demand response depends on the vehicle's flexibility and the benefits to owners. This paper adopts opportunity, delayed, and smart charging methods to quantify these impacts, flexibilities, and benefits. Simulation results show that delayed and smart charging methods can shift most charging events to lower TOU rate periods without compromising the charged energy and individual driver mobility needs.

  15. Electrostatic wire stabilizing a charged particle beam

    Science.gov (United States)

    Prono, D.S.; Caporaso, G.J.; Briggs, R.J.

    1983-03-21

    In combination with a charged particle beam generator and accelerator, apparatus and method are provided for stabilizing a beam of electrically charged particles. A guiding means, disposed within the particle beam, has an electric charge induced upon it by the charged particle beam. Because the sign of the electric charge on the guiding means and the sign of the particle beam are opposite, the particles are attracted toward and cluster around the guiding means to thereby stabilize the particle beam as it travels.

  16. Factors influencing the electrospray intrasource separation and selective ionization of glycerophospholipids.

    Science.gov (United States)

    Han, Xianlin; Yang, Kui; Yang, Jingyue; Fikes, Kora N; Cheng, Hua; Gross, Richard W

    2006-02-01

    The external electric field induces a separation of cations from negative electrolyte ions in the infusate while differential ionization of molecular species that possess differential electrical propensities can be induced in either the positive- or negative-ion mode during the electrospray ionization process. These physical and electrical processes that occur in the electrospray ion source have been used to selectively ionize lipid classes possessing different electrical propensities that are now known as "intrasource separation and selective ionization". However, the chemical principles underlying charge-dependent alterations in ionization efficiencies responsible for the selective ionization of lipid classes are not known with certainty. Herein, we examined the multiple factors that contribute to intrasource separation and selective ionization of lipid classes under optimal instrumental conditions. We demonstrated that many different lipid classes could be selectively ionized in the ion source and that intrasource resolution of distinct molecular constituents was independent of lipid concentration, flow rate, and residual ions under most experimental conditions. Moreover, the presence of alkaline conditions facilitates the selective ionization of many lipid classes through a mechanism independent of the design of the ESI ion source. Collectively, this study provides an empirical foundation for understanding the chemical mechanisms underlying intrasource separation and selective ionization of lipid classes that can potentially be used for global analysis of cellular lipidomes without the need for chromatographic separation.

  17. Different methods to alter surface morphology of high aspect ratio structures

    Energy Technology Data Exchange (ETDEWEB)

    Leber, M., E-mail: moritz.leber@utah.edu [Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT (United States); Shandhi, M.M.H. [Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT (United States); Hogan, A. [Blackrock Microsystems, Salt Lake City, UT (United States); Solzbacher, F. [Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT (United States); Bhandari, R.; Negi, S. [Department of Electrical and Computer Engineering, University of Utah, Salt Lake City, UT (United States); Blackrock Microsystems, Salt Lake City, UT (United States)

    2016-03-01

    Graphical abstract: Surface engineering of high aspect ratio silicon structures. - Highlights: • Multiple roughening techniques for high aspect ratio devices were investigated. • Modification of surface morphology of high aspect ratio silicon devices (1:15). • Decrease of 76% in impedance proves significant increase in surface area. - Abstract: In various applications such as neural prostheses or solar cells, there is a need to alter the surface morphology of high aspect ratio structures so that the real surface area is greater than geometrical area. The change in surface morphology enhances the devices functionality. One of the applications of altering the surface morphology is of neural implants such as the Utah electrode array (UEA) that communicate with single neurons by charge injection induced stimulation or by recording electrical neural signals. For high selectivity between single cells of the nervous system, the electrode surface area is required to be as small as possible, while the impedance is required to be as low as possible for good signal to noise ratios (SNR) during neural recording. For stimulation, high charge injection and charge transfer capacities of the electrodes are required, which increase with the electrode surface. Traditionally, researchers have worked with either increasing the roughness of the existing metallization (platinum grey, black) or other materials such as Iridium Oxide and PEDOT. All of these previously investigated methods lead to more complicated metal deposition processes that are difficult to control and often have a critical impact on the mechanical properties of the metal films. Therefore, a modification of the surface underneath the electrode's coating will increase its surface area while maintaining the standard and well controlled metal deposition process. In this work, the surfaces of the silicon micro-needles were engineered by creating a defined microstructure on the electrodes surface using several

  18. Different methods to alter surface morphology of high aspect ratio structures

    Science.gov (United States)

    Leber, M.; Shandhi, M. M. H.; Hogan, A.; Solzbacher, F.; Bhandari, R.; Negi, S.

    2016-03-01

    In various applications such as neural prostheses or solar cells, there is a need to alter the surface morphology of high aspect ratio structures so that the real surface area is greater than geometrical area. The change in surface morphology enhances the devices functionality. One of the applications of altering the surface morphology is of neural implants such as the Utah electrode array (UEA) that communicate with single neurons by charge injection induced stimulation or by recording electrical neural signals. For high selectivity between single cells of the nervous system, the electrode surface area is required to be as small as possible, while the impedance is required to be as low as possible for good signal to noise ratios (SNR) during neural recording. For stimulation, high charge injection and charge transfer capacities of the electrodes are required, which increase with the electrode surface. Traditionally, researchers have worked with either increasing the roughness of the existing metallization (platinum grey, black) or other materials such as Iridium Oxide and PEDOT. All of these previously investigated methods lead to more complicated metal deposition processes that are difficult to control and often have a critical impact on the mechanical properties of the metal films. Therefore, a modification of the surface underneath the electrode's coating will increase its surface area while maintaining the standard and well controlled metal deposition process. In this work, the surfaces of the silicon micro-needles were engineered by creating a defined microstructure on the electrodes surface using several methods such as laser ablation, focused ion beam, sputter etching, reactive ion etching (RIE) and deep reactive ion etching (DRIE). The surface modification processes were optimized for the high aspect ratio silicon structures of the UEA. The increase in real surface area while maintaining the geometrical surface area was verified using scanning electron

  19. Heterogeneity of monoclonal antibodies revealed by charge-sensitive methods.

    Science.gov (United States)

    Vlasak, J; Ionescu, R

    2008-12-01

    The expanding field of monoclonal antibody-based pharmaceuticals has triggered increased interest in analytical characterization of these large proteins and in understanding of their heterogeneity and degradation pathways. As a result, a large number of enzymatic modifications as well as chemical and physical degradations have been reported in monoclonal antibodies in recent years. Most heterogeneity is related to changes in the surface charge of the antibody, either directly, as a change in the number of charged residues, or indirectly as a chemical or physical alteration that changes surface-charge distribution. This review presents an overview of the sources of charge-related heterogeneity in monoclonal antibodies and the methods used for their detection. A detailed section is dedicated to deamidation of asparagine and isomerization of aspartic acid residues, two ubiquitous degradation pathways detected in antibodies and other proteins as well. Finally, kinetic modeling of the accumulation of antibody variants is presented as a tool to determine the expected fraction of molecules that have undergone one or more degradation reactions.

  20. Diffractive charged meson pair production

    CERN Document Server

    Lehmann-Dronke, B; Schäfer, S; Stein, E; Schäfer, A

    1999-01-01

    We investigate the possibility to measure the nonforward gluon distribution function by means of diffractively produced charged pion and kaon pairs in polarized lepton nucleon scattering. The resulting cross sections are sizable and are dominated by the gluonic contribution. We find large spin asymmetries, both for pion pairs and for kaon pairs.

  1. The Penetration of Shaped Charges

    Institute of Scientific and Technical Information of China (English)

    Wu Mingde

    1996-01-01

    @@ In order to get the best perforating effect, many facts have to be considered. Perforating job is often design by computer. A perforating engineer has to decide the perforating technology and procedure, the gun and charge system, the shot density and phasing, the penetration and hole size, etc.

  2. Floating liquid bridge charge dynamics

    Science.gov (United States)

    Teschke, Omar; Soares, David Mendez; Gomes, Whyllerson Evaristo; Valente Filho, Juracyr Ferraz

    2016-01-01

    The interaction of liquid with electric fields is investigated in a configuration where up to 13 kV are applied between electrodes resulting in a 106 V/m electric field in the capillaries and where there is the formation of a free-standing fluid bridge in the interelectrode gap. The Mott-Gurney equation was fitted to the measured ionization current vs applied voltage curve which indicates that the ionization rate at the high-voltage anode electrode dimethylsulfoxide (DMSO) interface and space charging in the interelectrode gap determine the floating liquid bridge current for a given cathode-to-anode voltage. Space charge effects were measured in the cathode becker and also at the liquid bridge since the ionized charges at the anode migrate to the bridge outer surface and decrease the interfacial tension from 43 mJ/m2 to 29 mJ/m2. Two distinct structural regions then form the bridge, a charged plastic (bulk modulus ˜100 MPa) conducting outer layer with a surface conductivity of ˜10-9 Ω-1, which shapes and supports the floating fluid structure, and an inner liquid cylinder, where DMSO molecules flow.

  3. Microscopic Charge Density Wave Transport

    NARCIS (Netherlands)

    Slot, Erwin

    2005-01-01

    This thesis describes the work performed on crystals with a phase transition to a Charge-Density Wave (CDW). The electrical transport properties change when crystal sizes are smaller than characteristic length scales for CDWs, typically 1 micrometer. In contrast to metals, semiconductors and superco

  4. Measurement of the Charge Asymmetry in Top Quark Pair Production

    Directory of Open Access Journals (Sweden)

    Böser Christian

    2012-06-01

    Full Text Available We present a measurement of the charge asymmetry in top quark pair production using an integrated luminosity of 1.09 fb−1 collected with the CMS detector. Top quark pairs with a signature of one electron or muon and four or more jets, at least one of them b tagged, are selected. At the LHC a small charge asymmetry in the rapidity distributions of top and antitop quarks is predicted. Therein slightly broader rapidity distributions for top quarks are expected, while antitop quarks are produced more centrally and possess narrower rapidity distributions. We determine the charge asymmetry based on two different sensitive variables and the results are compared with the most precise standard model theory predictions using a dedicated unfolding technique.

  5. First determination of the electric charge of the top quark

    CERN Document Server

    Abazov, V M; Abolins, M; Acharya, B S; Adams, M; Adams, T; Agelou, M; Ahn, S H; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Anastasoaie, M; Andeen, T; Anderson, S; Andrieu, B; Anzelc, M S; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Assis-Jesus, A C S; Atramentov, O; Autermann, C; Avila, C; Ay, C; Badaud, F; Baden, A; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, P; Banerjee, S; Barberis, E; Bargassa, P; Baringer, P; Barnes, C; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Bellavance, A; Benítez, J A; Beri, S B; Bernardi, G; Bernhard, R; Berntzon, L; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Binder, M; Biscarat, C; Black, K M; Blackler, I; Blazey, G; Blekman, F; Blessing, S; Bloch, D; Bloom, K; Blumenschein, U; Böhnlein, A; Boeriu, O; Bolton, T A; Borissov, G; Bos, K; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Buchanan, N J; Buchholz, D; Bühler, M; Büscher, V; Burdin, S; Burke, S; Burnett, T H; Busato, E; Buszello, C P; Butler, J M; Calfayan, P; Calvet, S; Cammin, J; Caron, S; Carvalho, W; Casey, B C K; Cason, N M; Castilla-Valdez, H; Chakraborty, D; Chan, K M; Chandra, A; Charles, F; Cheu, E; Chevallier, F; Cho, D K; Choi, S; Choudhary, B; Christofek, L; Claes, D; Clement, B; Clément, C; Coadou, Y; Cooke, M; Cooper, W E; Coppage, D; Corcoran, M; Cousinou, M C; Cox, B; Crepe-Renaudin, S; Cutts, D; Cwiok, M; Da Motta, H; Das, A; Das, M; Davies, B; Davies, G; Davis, G A; De, K; de Jong, P; De Jong, S J; De La Cruz-Burelo, E; De Oliveira Martins, C; Degenhardt, J D; Déliot, F; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doidge, M; Dominguez, A; Dong, H; Dudko, L V; Duflot, L; Dugad, S R; Duggan, D; Duperrin, A; Dyer, J; Dyshkant, A; Eads, M; Edmunds, D; Edwards, T; Ellison, J; Elmsheuser, J; Elvira, V D; Eno, S; Ermolov, P; Evans, H; Evdokimov, A; Evdokimov, V N; Fatakia, S N; Feligioni, L; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fleck, I; Ford, M; Fortner, M; Fox, H; Fu, S; Fuess, S; Gadfort, T; Galea, C F; Gallas, E; Galyaev, E; García, C; García-Bellido, A; Gardner, J; Gavrilov, V; Gay, A; Gay, P; Gelé, D; Gelhaus, R; Gerber, C E; Gershtein, Yu; Gillberg, D; Ginther, G; Gollub, N; Gómez, B; Goussiou, A; Grannis, P D; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, P; Grivaz, J F; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutíerrez, G; Gutíerrez, P; Haas, A; Hadley, N J; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Hanagaki, K; Hansson, P; Harder, K; Harel, A; Harrington, R; Hauptman, J M; Hauser, R; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinmiller, J M; Heinson, A P; Heintz, U; Hensel, C; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Hoeth, H; Hohlfeld, M; Hong, S J; Hooper, R; Houben, P; Hu, Y; Hubacek, Z; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jarvis, C; Jenkins, A; Jesik, R; Johns, K; Johnson, C; Johnson, M; Jonckheere, A; Jonsson, P; Juste, A; Käfer, D; Kahn, S; Kajfasz, E; Kalinin, A M; Kalk, J M; Kalk, J R; Kappler, S; Karmanov, D; Kasper, J; Kasper, P; Katsanos, I; Kau, D; Kaur, R; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A I; Kharzheev, Yu M; Khatidze, D; Kim, H; Kim, T J; Kirby, M H; Klima, B; Kohli, J M; Konrath, J P; Kopal, M; Korablev, V M; Kotcher, J; Kothari, B; Koubarovsky, A; Kozelov, A V; Kozminski, J; Krop, D; Kryemadhi, A; Kühl, T; Kumar, A; Kunori, S; Kupco, A; Kurca, T; Kvita, J; Lammers, S; Landsberg, G L; Lazoflores, J; Le Bihan, A C; Lebrun, P; Lee, W M; Leflat, A; Lehner, F; Lesne, V; Lévêque, J; Lewis, P; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Z; Lobo, L; Lobodenko, A; Lokajícek, M; Lounis, A; Love, P; Lubatti, H J; Lynker, M; Lyon, A L; Maciel, A K A; Madaras, R J; Mättig, P; Magass, C; Magerkurth, A; Magnan, A M; Makovec, N; Mal, P K; Malbouisson, H B; Malik, S; Malyshev, V L; Mao, H S; Maravin, Y; Martens, M; McCarthy, R; Meder, D; Melnitchouk, A; Mendes, A; Mendoza, L; Merkin, M; Merritt, K W; Meyer, A; Meyer, J; Michaut, M; Miettinen, H; Millet, T; Mitrevski, J; Molina, J; Mondal, N K; Monk, J; Moore, R W; Moulik, T; Muanza, G S; Mulders, M; Mulhearn, M; Mundim, L; Mutaf, Y D; Nagy, E; Naimuddin, M; Narain, M; Naumann, N A; Neal, H A; Negret, J P; Neustroev, P; Nöding, C; Nomerotski, A; Novaes, S F; Nunnemann, T; O'Dell, V; O'Neil, D C; Obrant, G; Oguri, V; Oliveira, N; Oshima, N; Otec, R; Oteroy-Garzon, G J; Owen, M; Padley, P; Parashar, N; Park, S J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Pawloski, G; Perea, P M; Pérez, E; Peters, K; Petroff, P; Petteni, M; Piegaia, R; Piper, J; Pleier, M A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M E; Pompos, A; Pope, B G; Popov, A V; Potter, C; Prado da Silva, W L; Prosper, H B; Protopopescu, S D; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Rani, K J; Ranjan, K; Ratoff, P N; Renkel, P; Reucroft, S; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F K; Robinson, S; Rodrigues, R F; Royon, C; Rubinov, P; Ruchti, R; Rud, V I; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Santoro, A F S; Savage, G; Sawyer, L; Scanlon, T; Schaile, A D; Schamberger, R D; Scheglov, Y; Schellman, H; Schieferdecker, P; Schmitt, C; Schwanenberger, C; Schwartzman, A; Schwienhorst, R; Sekaric, J; Sen-Gupta, S; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shephard, W D; Shivpuri, R K; Shpakov, D; Siccardi, V; Sidwell, R A; Simák, V; Sirotenko, V I; Skubic, P L; Slattery, P F; Smith, R P; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Song, X; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Souza, M; Spurlock, B; Stark, J; Steele, J; Stolin, V; Stone, A; Stoyanova, D A; Strandberg, J; Strandberg, S; Strang, M A; Strauss, M; Ströhmer, R; Strom, D; Strovink, M; Stutte, L; Sumowidagdo, S; Sznajder, A; Talby, M; Tamburello, P; Taylor, W; Telford, P; Temple, J; Tiller, B; Titov, M; Tokmenin, V V; Tomoto, M; Toole, T; Torchiani, I; Towers, S; Trefzger, T; Trincaz-Duvoid, S; Tsybychev, D; Tuchming, B; Tully, C; Turcot, A S; Tuts, P M; Unalan, R; Uvarov, L; Uvarov, S; Uzunyan, S; Vachon, B; vanden Berg, P J; Van Kooten, R; Van Leeuwen, W M; Varelas, N; Varnes, E W; Vartapetian, A H; Vasilyev, I A; Vaupel, M; Verdier, P; Vertogradov, L S; Verzocchi, M; Villeneuve-Séguier, F; Vint, P; Vlimant, J R; Von Törne, E; Voutilainen, M; Vreeswijk, M; Wahl, H D; Wang, L; Wang, M H L; Warchol, J; Watts, G; Wayne, M; Weber, M; Weerts, H; Wermes, N; Wetstein, M; White, A; Wicke, D; Wilson, G W; Wimpenny, S J; Wobisch, M; Womersley, J; Wood, D R; Wyatt, T R; Xie, Y; Xuan, N; Yacoob, S; Yamada, R; Yan, M; Yasuda, T; Yatsunenko, Y A; Yip, K; Yoo, H D; Youn, S W; Yu, C; Yu, J; Yurkewicz, A; Zatserklyaniy, A; Zeitnitz, C; Zhang, D; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G

    2007-01-01

    We present the first determination of the electric charge of the top quark, using top quark pairs (ttbar) produced in ppbar collisions at sqrt(s)=1.96 TeV by the Fermilab Tevatron collider. We use 370 pb-1 of data collected by the D0 experiment and select events with at least one high transverse momentum electron or muon, high transverse energy imbalance, and four or more jets. We discriminate between b- and bbar-quark jets by using the charge and momenta of tracks within the jet cones. The data is consistent with the expected electric charge, |q|=2e/3. We exclude, at the 92% C.L., that the sample is solely due to the production of exotic quark pairs QQbar with |q|=4e/3. We place an upper limit on the fraction of QQbar pairs rho < 0.80 at the 90% C.L.

  6. Multiple charge beam dynamics in alternate phase focusing structure

    Directory of Open Access Journals (Sweden)

    S. Dechoudhury

    2014-07-01

    Full Text Available Asymmetrical alternate phase (A-APF focusing realized in a sequence of 36 superconducting quarter wave resonators (QWRs has been shown to accelerate almost 81% of input uranium beam before foil stripper to an energy of 6.2  MeV/u from 1.3  MeV/u. Ten charge states from 34+ to 43+ could be simultaneously accelerated with the phase of resonators tuned for 34+. The A-APF structure showed the unique nature of a large potential bucket for charge states higher than that of the tuned one. Steering inherent to QWRs can be mitigated by selecting appropriate phase variation of the APF periods and optimization of solenoid field strengths placed in each of the periods. This mitigation facilitates the multiple charge state acceleration scheme.

  7. Complexation behavior of oppositely charged polyelectrolytes: Effect of charge distribution

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Mingtian; Li, Baohui, E-mail: dliang@pku.edu.cn, E-mail: baohui@nankai.edu.cn [School of Physics and Key Laboratory of Functional Polymer Materials of Ministry of Education, Nankai University, Tianjin 300071 (China); Zhou, Jihan; Su, Cuicui; Niu, Lin; Liang, Dehai, E-mail: dliang@pku.edu.cn, E-mail: baohui@nankai.edu.cn [Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China)

    2015-05-28

    Complexation behavior of oppositely charged polyelectrolytes in a solution is investigated using a combination of computer simulations and experiments, focusing on the influence of polyelectrolyte charge distributions along the chains on the structure of the polyelectrolyte complexes. The simulations are performed using Monte Carlo with the replica-exchange algorithm for three model systems where each system is composed of a mixture of two types of oppositely charged model polyelectrolyte chains (EGEG){sub 5}/(KGKG){sub 5}, (EEGG){sub 5}/(KKGG){sub 5}, and (EEGG){sub 5}/(KGKG){sub 5}, in a solution including explicit solvent molecules. Among the three model systems, only the charge distributions along the chains are not identical. Thermodynamic quantities are calculated as a function of temperature (or ionic strength), and the microscopic structures of complexes are examined. It is found that the three systems have different transition temperatures, and form complexes with different sizes, structures, and densities at a given temperature. Complex microscopic structures with an alternating arrangement of one monolayer of E/K monomers and one monolayer of G monomers, with one bilayer of E and K monomers and one bilayer of G monomers, and with a mixture of monolayer and bilayer of E/K monomers in a box shape and a trilayer of G monomers inside the box are obtained for the three mixture systems, respectively. The experiments are carried out for three systems where each is composed of a mixture of two types of oppositely charged peptide chains. Each peptide chain is composed of Lysine (K) and glycine (G) or glutamate (E) and G, in solution, and the chain length and amino acid sequences, and hence the charge distribution, are precisely controlled, and all of them are identical with those for the corresponding model chain. The complexation behavior and complex structures are characterized through laser light scattering and atomic force microscopy measurements. The order

  8. Search for fractionally charged particles in pp collisions at s=7TeV

    Science.gov (United States)

    Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hammer, J.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Knünz, V.; Krammer, M.; Krätschmer, I.; Liko, D.; Mikulec, I.; Pernicka, M.; Rahbaran, B.; Rohringer, C.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Taurok, A.; Waltenberger, W.; Walzel, G.; Widl, E.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Bansal, M.; Bansal, S.; Cornelis, T.; De Wolf, E. A.; Janssen, X.; Luyckx, S.; Mucibello, L.; Ochesanu, S.; Roland, B.; Rougny, R.; Selvaggi, M.; Staykova, Z.; Van Haevermaet, H.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Blekman, F.; Blyweert, S.; D'Hondt, J.; Gonzalez Suarez, R.; Kalogeropoulos, A.; Maes, M.; Olbrechts, A.; Van Doninck, W.; Van Mulders, P.; Van Onsem, G. P.; Villella, I.; Clerbaux, B.; De Lentdecker, G.; Dero, V.; Gay, A. P. R.; Hreus, T.; Léonard, A.; Marage, P. E.; Mohammadi, A.; Reis, T.; Thomas, L.; Vander Marcken, G.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Adler, V.; Beernaert, K.; Cimmino, A.; Costantini, S.; Garcia, G.; Grunewald, M.; Klein, B.; Lellouch, J.; Marinov, A.; Mccartin, J.; Ocampo Rios, A. A.; Ryckbosch, D.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Verwilligen, P.; Walsh, S.; Yazgan, E.; Zaganidis, N.; Basegmez, S.; Bruno, G.; Castello, R.; Ceard, L.; Delaere, C.; du Pree, T.; Favart, D.; Forthomme, L.; Giammanco, A.; Hollar, J.; Lemaitre, V.; Liao, J.; Militaru, O.; Nuttens, C.; Pagano, D.; Pin, A.; Piotrzkowski, K.; Schul, N.; Vizan Garcia, J. M.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Alves, G. A.; Correa Martins Junior, M.; De Jesus Damiao, D.; Martins, T.; Pol, M. E.; Souza, M. H. G.; Aldá Júnior, W. L.; Carvalho, W.; Custódio, A.; Da Costa, E. M.; De Oliveira Martins, C.; Fonseca De Souza, S.; Matos Figueiredo, D.; Mundim, L.; Nogima, H.; Oguri, V.; Prado Da Silva, W. L.; Santoro, A.; Soares Jorge, L.; Sznajder, A.; Anjos, T. S.; Bernardes, C. A.; Dias, F. A.; Tomei, T. R. Fernandez Perez; Gregores, E. M.; Lagana, C.; Marinho, F.; Mercadante, P. G.; Novaes, S. F.; Padula, Sandra S.; Genchev, V.; Iaydjiev, P.; Piperov, S.; Rodozov, M.; Stoykova, S.; Sultanov, G.; Tcholakov, V.; Trayanov, R.; Vutova, M.; Dimitrov, A.; Hadjiiska, R.; Kozhuharov, V.; Litov, L.; Pavlov, B.; Petkov, P.; Bian, J. G.; Chen, G. M.; Chen, H. S.; Jiang, C. H.; Liang, D.; Liang, S.; Meng, X.; Tao, J.; Wang, J.; Wang, X.; Wang, Z.; Xiao, H.; Xu, M.; Zang, J.; Zhang, Z.; Asawatangtrakuldee, C.; Ban, Y.; Guo, Y.; Li, W.; Liu, S.; Mao, Y.; Qian, S. J.; Teng, H.; Wang, D.; Zhang, L.; Zou, W.; Avila, C.; Gomez, J. P.; Gomez Moreno, B.; Osorio Oliveros, A. F.; Sanabria, J. C.; Godinovic, N.; Lelas, D.; Plestina, R.; Polic, D.; Puljak, I.; Antunovic, Z.; Kovac, M.; Brigljevic, V.; Duric, S.; Kadija, K.; Luetic, J.; Morovic, S.; Attikis, A.; Galanti, M.; Mavromanolakis, G.; Mousa, J.; Nicolaou, C.; Ptochos, F.; Razis, P. A.; Finger, M.; Finger, M., Jr.; Assran, Y.; Elgammal, S.; Ellithi Kamel, A.; Khalil, S.; Mahmoud, M. A.; Radi, A.; Kadastik, M.; Müntel, M.; Raidal, M.; Rebane, L.; Tiko, A.; Eerola, P.; Fedi, G.; Voutilainen, M.; Härkönen, J.; Heikkinen, A.; Karimäki, V.; Kinnunen, R.; Kortelainen, M. J.; Lampén, T.; Lassila-Perini, K.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Peltola, T.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Ungaro, D.; Wendland, L.; Banzuzi, K.; Karjalainen, A.; Korpela, A.; Tuuva, T.; Besancon, M.; Choudhury, S.; Dejardin, M.; Denegri, D.; Fabbro, B.; Faure, J. L.; Ferri, F.; Ganjour, S.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Locci, E.; Malcles, J.; Millischer, L.; Nayak, A.; Rander, J.; Rosowsky, A.; Shreyber, I.; Titov, M.; Baffioni, S.; Beaudette, F.; Benhabib, L.; Bianchini, L.; Bluj, M.; Broutin, C.; Busson, P.; Charlot, C.; Daci, N.; Dahms, T.; Dobrzynski, L.; Granier de Cassagnac, R.; Haguenauer, M.; Miné, P.; Mironov, C.; Naranjo, I. N.; Nguyen, M.; Ochando, C.; Paganini, P.; Sabes, D.; Salerno, R.; Sirois, Y.; Veelken, C.; Zabi, A.; Agram, J.-L.; Andrea, J.; Bloch, D.; Bodin, D.; Brom, J.-M.; Cardaci, M.; Chabert, E. C.; Collard, C.; Conte, E.; Drouhin, F.; Ferro, C.; Fontaine, J.-C.; Gelé, D.; Goerlach, U.; Juillot, P.; Le Bihan, A.-C.; Van Hove, P.; Fassi, F.; Mercier, D.; Beauceron, S.; Beaupere, N.; Bondu, O.; Boudoul, G.; Chasserat, J.; Chierici, R.; Contardo, D.; Depasse, P.; El Mamouni, H.; Fay, J.; Gascon, S.; Gouzevitch, M.; Ille, B.; Kurca, T.; Lethuillier, M.; Mirabito, L.; Perries, S.; Sgandurra, L.; Sordini, V.; Tschudi, Y.; Verdier, P.; Viret, S.; Tsamalaidze, Z.; Anagnostou, G.; Autermann, C.; Beranek, S.; Edelhoff, M.; Feld, L.; Heracleous, N.; Hindrichs, O.

    2013-05-01

    A search is presented for free heavy long-lived fractionally charged particles produced in pp collisions at s=7TeV. The data sample was recorded by the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0fb-1. Candidate fractionally charged particles are identified by selecting tracks with associated low charge measurements in the silicon tracking detector. Observations are found to be consistent with expectations for background processes. The results of the search are used to set upper limits on the cross section for pair production of fractionally charged, massive spin-1/2 particles that are neutral under SU(3)C and SU(2)L. We exclude at 95% confidence level such particles with electric charge ±2e/3 with masses below 310 GeV, and those with charge ±e/3 with masses below 140 GeV.

  9. Measurement of the atmospheric muon charge ratio with the OPERA detector

    CERN Document Server

    Agafonova, N; Aoki, S; Ariga, A; Ariga, T; Autiero, D; Badertscher, A; Bagulya, A; Bertolin, A; Besnier, M; Bick, D; Boyarkin, V; Bozza, C; Brugière, T; Brugnera, R; Brunetti, G; Buontempo, S; Cazes, A; Chaussard, L; Chernyavsky, M; Chiarella, V; Chon-Sen, N; Chukanov, A; Cozzi, M; D'Amato, G; Corso, F Dal; D'Ambrosio, N; De Lellis, G; D'eclais, Y; De Serio, M; Di Capua, F; Di Ferdinando, D; Di Giovanni, A; Di Marco, N; Dmitrievski, S; Dracos, M; Duchesneau, D; Dusini, S; Ebert, J; Egorov, O; Enikeev, R; Ereditato, A; Esposito, L S; Favier, J; Felici, G; Ferber, T; Fini, R; Frekers, D; Fukuda, T; Fukushima, C; Galkin, V I; Garfagnini, A; Giacomelli, G; Giorgini, M; Goellnitz, C; Goldberg, J; Golubkov, D; Goncharova, L; Gornushkin, Y; Grella, G; Grianti, F; Guler, M; Gustavino, C; Hagner, C; Hamada, K; Hara, T; Hierholzer, M; Hoshino, K; Ieva, M; Jakovcic, K; Jollet, C; Juget, F; Kazuyama, M; Kim, S H; Kimura, M; Klicek, B; Knuesel, J; Kodama, K; Komatsu, M; Kose, U; Kreslo, I; Kubota, H; Lazzaro, C; Lenkeit, J; Ljubicic, A; Longhin, A; Lutter, G; Malgin, A; Mandrioli, G; Marotta, A; Marteau, J; Matsuo, T; Matveev, V; Mauri, N; Medinaceli, E; Meisel, F; Meregaglia, A; Migliozzi, P; Mikado, S; Miyamoto, S; Monacelli, P; Morishima, K; Moser, U; Muciaccia, M T; Naganawa, N; Naka, T; Nakamura, M; Nakano, T; Naumov, D; Nikitina, V; Niwa, K; Nonoyama, Y; Ogawa, S; Olchevski, A; Oldorf, C; Orlova, G; Osedlo, V; Paniccia, M; Paoloni, A; Park, B D; Park, I G; Pastore, A; Patrizii, L; Pennacchio, E; Pessard, H; Pilipenko, V; Pistillo, C; Policastro, G; Polukhina, N; Pozzato, M; Pretzl, K; Publichenko, P; Pupilli, F; Rescigno, R; Roganova, T; Rokujo, H; Romano, G; Rosa, G; Rostovtseva, I; Rubbia, A; Russo, A; Ryasny, V; Ryazhskaya, O; Sato, O; Sato, Y; Schembri, A; Parzefall, W Schmidt; Schroeder, H; Lavina, L Scotto; Sheshukov, A; Shibuya, H; Simone, S; Sioli, M; Sirignano, C; Sirri, G; Song, J S; Spinetti, M; Stanco, L; Starkov, N; Stipcevic, M; Strauss, T; Strolin, P; Takahashi, S; Tenti, M; Terranova, F; Tezuka, I; Tioukov, V; Tolun, P; Tran, T; Tufanli, S; Vilain, P; Vladimirov, M; Votano, L; Vuilleumier, J L; Wilquet, G; Wonsak, B; Yakushev, V; Yoon, C S; Yoshioka, T; Yoshida, J; Zaitsev, Y; Zemskova, S; Zghiche, A; Zimmermann, R

    2010-01-01

    The OPERA detector at the Gran Sasso underground laboratory (LNGS) was used to measure the atmospheric muon charge ratio in the TeV energy region. We analyzed 403069 atmospheric muons corresponding to 113.4 days of livetime during the 2008 CNGS run. We computed separately the muon charge ratio for single and for multiple muon events in order to select different energy regions of the primary cosmic ray spectrum and to test the charge ratio dependence on the primary composition. The measured charge ratio values were corrected taking into account the charge-misidentification errors. Data have also been grouped in five bins of the "vertical surface energy". A fit to a simplified model of muon production in the atmosphere allowed the determination of the pion and kaon charge ratios weighted by the cosmic ray energy spectrum.

  10. Testing, Performance and Reliability Evaluation of Charge Controllers for Solar Photovoltaic Home Lighting System in India

    Directory of Open Access Journals (Sweden)

    Adarsh Kumar

    2016-01-01

    Full Text Available :Charge controller is the most important part of a Solar Photovoltaic Home LightingSystem (SPVHLS which controls the charging ofbattery from photovoltaic (PV module and discharging of battery through load. This paper analyzes testresults of fourteen charge controllers (CC available in Indiaaccording to the Ministry of New and RenewableEnergy (MNRE specification. The different parameters of charge controllers to be tested arebattery high voltage disconnect (HVD, low voltage disconnect(LVD, load reconnect voltage (LRV, short circuit protection etc. It is found thatseven charge controllers meet the technical specifications ofMNRE. There is also a study of different features and properties of the chargecontrollers. Finally a brief discussion on selection appropriate charge controller for Solar Photovoltaic Home LightingSystem (SPVHLS and further improvement ofcharge controller is presented.

  11. Search for fractionally charged particles in pp collisions at $\\sqrt{s}$ = 7 TeV

    CERN Document Server

    Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Aguilo, Ernest; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hammer, Josef; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Krätschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Pernicka, Manfred; Rahbaran, Babak; Rohringer, Christine; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Waltenberger, Wolfgang; Walzel, Gerhard; Widl, Edmund; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Luyckx, Sten; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Selvaggi, Michele; Staykova, Zlatka; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Gonzalez Suarez, Rebeca; Kalogeropoulos, Alexis; Maes, Michael; Olbrechts, Annik; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Clerbaux, Barbara; De Lentdecker, Gilles; Dero, Vincent; Gay, Arnaud; Hreus, Tomas; Léonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Reis, Thomas; Thomas, Laurent; Vander Marcken, Gil; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Cimmino, Anna; Costantini, Silvia; Garcia, Guillaume; Grunewald, Martin; Klein, Benjamin; Lellouch, Jérémie; Marinov, Andrey; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Verwilligen, Piet; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Bruno, Giacomo; Castello, Roberto; Ceard, Ludivine; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Schul, Nicolas; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; De Jesus Damiao, Dilson; Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Aldá Júnior, Walter Luiz; Carvalho, Wagner; Custódio, Analu; Da Costa, Eliza Melo; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Oguri, Vitor; Prado Da Silva, Wanda Lucia; Santoro, Alberto; Soares Jorge, Luana; Sznajder, Andre; Souza Dos Anjos, Tiago; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Lagana, Caio; Da Cunha Marinho, Franciole; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Piperov, Stefan; Rodozov, Mircho; Stoykova, Stefka; Sultanov, Georgi; Tcholakov, Vanio; Trayanov, Rumen; Vutova, Mariana; Dimitrov, Anton; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Tao, Junquan; Wang, Jian; Wang, Xianyou; Wang, Zheng; Xiao, Hong; Xu, Ming; Zang, Jingjing; Zhang, Zhen; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Osorio Oliveros, Andres Felipe; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Plestina, Roko; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Duric, Senka; Kadija, Kreso; Luetic, Jelena; Morovic, Srecko; Attikis, Alexandros; Galanti, Mario; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Khalil, Shaaban; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Müntel, Mait; Raidal, Martti; Rebane, Liis; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Härkönen, Jaakko; Heikkinen, Mika Aatos; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Ungaro, Donatella; Wendland, Lauri; Banzuzi, Kukka; Karjalainen, Ahti; Korpela, Arja; Tuuva, Tuure; Besancon, Marc

    2013-01-01

    A search is presented for free heavy long-lived fractionally charged particles produced in pp collisions at $\\sqrt{s}$ = 7 TeV. The data sample was recorded by the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 inverse femtobarns. Candidate fractionally charged particles are identified by selecting tracks with associated low charge measurements in the silicon tracking detector. Observations are found to be consistent with expectations for background processes. The results of the search are used to set upper limits on the cross section for pair production of fractionally charged, massive spin-1/2 particles that are neutral under SU(3)$_C$ and SU(2)$_L$. We exclude at 95% confidence level such particles with electric charge ±2e/3 with masses below 310 GeV, and those with charge ±e/3 with masses below 140 GeV.

  12. Role of acetylation and charge in antimicrobial peptides based on human beta-defensin-3.

    Science.gov (United States)

    Papanastasiou, Emilios Andrew; Hua, Quyen; Sandouk, Aline; Son, U Hyon; Christenson, Andrew James; Van Hoek, Monique Louise; Bishop, Barney Michael

    2009-07-01

    Cationic antimicrobial peptides are an evolutionarily ancient and essential element of innate immunity in higher organisms. The precise mechanism by which these peptides exert their antimicrobial activity on bacteria is not well understood. Decapeptides based on the C-terminus of human beta-defensin-3 were designed and evaluated to study the role of charge in defining the antimicrobial activity and selectivity of these peptides against Escherichia coli. Acetylated derivatives of these peptides were prepared in order to further evaluate how positively charged primary amines contribute to potency in these small antimicrobial peptides. These peptides enabled us to explore the relationship between net charge, charge distribution and antimicrobial activity. While the results indicate that net charge is a major factor in antimicrobial activity in these peptides, the actual relationship between charge and potency appears to be more complex.

  13. Electron capture by highly charged ions from surfaces and gases

    Energy Technology Data Exchange (ETDEWEB)

    Allen, F.

    2008-01-11

    In this study highly charged ions produced in Electron Beam Ion Traps are used to investigate electron capture from surfaces and gases. The experiments with gas targets focus on spectroscopic measurements of the K-shell x-rays emitted at the end of radiative cascades following electron capture into Rydberg states of Ar{sup 17+} and Ar{sup 18+} ions as a function of collision energy. The ions are extracted from an Electron Beam Ion Trap at an energy of 2 keVu{sup -1}, charge-selected and then decelerated down to 5 eVu{sup -1} for interaction with an argon gas target. For decreasing collision energies a shift to electron capture into low orbital angular momentum capture states is observed. Comparative measurements of the K-shell x-ray emission following electron capture by Ar{sup 17+} and Ar{sup 18+} ions from background gas in the trap are made and a discrepancy in the results compared with those from the extraction experiments is found. Possible explanations are discussed. For the investigation of electron capture from surfaces, highly charged ions are extracted from an Electron Beam Ion Trap at energies of 2 to 3 keVu{sup -1}, charge-selected and directed onto targets comprising arrays of nanoscale apertures in silicon nitride membranes. The highly charged ions implemented are Ar{sup 16+} and Xe{sup 44+} and the aperture targets are formed by focused ion beam drilling in combination with ion beam assisted thin film deposition, achieving hole diameters of 50 to 300 nm and aspect ratios of 1:5 to 3:2. After transport through the nanoscale apertures the ions pass through an electrostatic charge state analyzer and are detected. The percentage of electron capture from the aperture walls is found to be much lower than model predictions and the results are discussed in terms of a capillary guiding mechanism. (orig.)

  14. Alteration of in vivo cellulose ribbon assembly by carboxymethylcellulose and other cellulose derivatives

    OpenAIRE

    1982-01-01

    In vivo cellulose ribbon assembly by the Gram-negative bacterium Acetobacter xylinum can be altered by incubation in carboxymethylcellulose (CMC), a negatively charged water-soluble cellulose derivative, and also by incubation in a variety of neutral, water-soluble cellulose derivatives. In the presence of all of these substituted celluloses, normal fasciation of microfibril bundles to form the typical twisting ribbon is prevented. Alteration of ribbon assembly is most extensive in the presen...

  15. Alteraciones en el largo de la cola y su asociación con caracteres de fertilidad en ratones CF1 seleccionados por peso Alterations in tail length and its association with fertility characters in CF1 mice selected for weight

    Directory of Open Access Journals (Sweden)

    S.F. Bernardi

    2011-12-01

    Full Text Available En una población testigo (t de ratones de la cepa CF1 y en dos pares de líneas de selección divergente para peso (s y h: negativas; s’ y h’: positivas derivadas de la primera, fundadas y criadas en la Facultad de Ciencias Veterinarias de la Universidad Nacional de Rosario, se presentaron animales con alteraciones en las colas y ausencia de vértebras caudales en baja frecuencia. Para estimar las relaciones entre longitud de cola (LC, número de vértebras caudales (V, peso (P y caracteres de fertilidad, se midió LC en mm, se contó V mediante radiografías, se observaron caracteres estructurales en ovarios y testículos por microscopía óptica. Por aplicación de ANOVA y pruebas de comparaciones múltiples se probó que las líneas difirieron en LC (p0,05 en el sentido de la selección de P (machos: LCh=8,4; LCs=8,8; LCt=9,0; LCh’=9,2; LCs’=9,8. Los ratones con ausencias de vértebras caudales (cc tuvieron en promedio la mitad de V que los animales con colas fenotípicamente normales (cn. Cuando los cc se compararon con los cn (p0,05 se observó un menor tamaño de las gónadas en ambos sexos, un menor diámetro del túbulo seminífero en machos y un menor número de cuerpos lúteos en hembras. LC se modificó como respuesta correlacionada a la selección de peso, pero la presencia de animales con malformaciones en la cola se debería a mutaciones que podrían estar asociadas con fertilidad.In a control population (t and in two pairs of lines of two-way selection for body weight (s and h: downward selection; s’ and h’: upward selection, mice with tail alterations and absence of caudal vertebrae were presented with low frecuency from line foundation. To estimate the relations among tail length (LC, number of caudal vertebrae (V, weight (P and fertility characters, LC was measured in mm, V was counted by X-rays, structural characters in ovaries and testicles were observed by optical microscopy. It was tested, by ANOVA and multiple

  16. Research on Battery Charging-Discharging in New Energy Systems

    Directory of Open Access Journals (Sweden)

    Che Yanbo

    2013-07-01

    Full Text Available As an energy storage component, the battery plays increasingly important role in new energy industry. Charging and discharging system is the vital part of the application of the battery, but the charge and discharge are always designed separately and carried by different part in the traditional application. Additionally, most battery discharge mode and method are always simplified which cannot ensure to meet the demand of power utilization. In the actual energy storage system, the design of the energy converter, which make the power storage and supply as a whole and the design of the charge and discharge method, will play an important role in efficient utilization of the battery system. As a part of the new energy system, the study makes battery and the charging and discharging system as a whole to store energy, which can store and release electric energy high efficiently according to the system state and control the bidirectional flow of energy precisely. Using TMS320F2812 as the control core, the system which integrates charging and discharging with battery monitoring can achieve the bidirectional Buck/Boost power control. It can achieve three-stage charging and selective discharging of the battery. Due to the influence of the diode reverse recovery time, current oscillation will appear. In order to eliminate the oscillation, we can set the circuit to work in critical conduction mode. The experimental result shows that the system can achieve the charging and discharging control of lead-acid battery and increase the battery life time further.

  17. [Natural selection].

    Science.gov (United States)

    Mayr, E

    1985-05-01

    Much of the resistance against Darwin's theory of natural selection has been due to misunderstandings. It is shown that natural selection is not a tautology and that it is a two-step process. The first step, the production of variation, is under the control of chance; the second step, selection proper, is an anti-chance process, but subject to many constraints. The target of selection is the individual as a whole, and many neutral mutations can be retained as hitchhikers of successful genotypes. Sexual selection results from selection for pure reproductive success.

  18. Nanoparticle gel electrophoresis: bare charged spheres in polyelectrolyte hydrogels.

    Science.gov (United States)

    Li, Fei; Hill, Reghan J

    2013-03-15

    Nanoparticle gel electrophoresis has recently emerged as an attractive means of separating and characterizing nanoparticles. Consequently, a theory that accounts for electroosmotic flow in the gel, and coupling of the nanoparticle and hydrogel electrostatics and hydrodynamics, is required, particularly for gels in which the mesh size is comparable to or smaller than the particle radii. Here, we present an electrokinetic model for charged, spherical colloidal particles undergoing electrophoresis in charged (polyelectrolyte) hydrogels: the gel-electrophoresis analogue of Henry's theory for electrophoresis in Newtonian electrolytes. We compare numerically exact solutions of the model with several independent asymptotic approximations, identifying regions in the parameter space where these approximations are accurate or break down. As previously assumed in the literature, Henry's formula, modified by the addition of a constant electroosmotic flow mobility, is accurate only for nanoparticles that are small compared to the hydrogel mesh size. We derived an exact analytical solution of the full model by judiciously modifying the theory of Allison et al. for uncharged gels, drawing on the superposition methodology of Doane et al. to account for hydrogel charge. This furnishes accurate and economical mobility predictions for the entire parameter space. The present model suggests that nanoparticle size separations (with diameters ≲40 nm) are optimal at low ionic strength, with a gel mesh size that is selected according to the particle charging mechanism. For weakly charged particles, optimal size separation is achieved when the Brinkman screening length is matched to the mean particle size. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Charge Exchange Effect on Space-Charge-Limited Current Densities in Ion Diode

    Institute of Scientific and Technical Information of China (English)

    石磊

    2002-01-01

    The article theoretically studied the charge-exchange effects on space charge limited electron and ion current densities of non-relativistic one-dimensional slab ion diode, and compared with those of without charge exchange.

  20. CHARGE '

    African Journals Online (AJOL)

    2005-11-30

    Nov 30, 2005 ... events that initiate the lecture may carry much pain occasioned .... deepened my resolve to do whatever I could to help. Rwanda” .... You just need to ask anyone of them!!! .... How do we feel if we find ourselves at the receiving.

  1. Stability of charged strange quark stars

    Energy Technology Data Exchange (ETDEWEB)

    Arbañil, José D. V.; Malheiro, Manuel [Departamento de Física, Instituto Tecnológico de Aeronáutica, Centro Técnico Aeroespacial, 12228-900 São José dos Campos, SP (Brazil)

    2015-12-17

    We investigate the hydrostatic equilibrium and the stability of charged stars made of a charged perfect fluid. The matter contained in the star follows the MIT bag model equation of state and the charge distribution to a power-law of the radial coordinate. The hydrostatic equilibrium and the stability of charged strange stars are analyzed using the Tolman-Oppenheimer-Volkoff equation and the Chandrasekhar’s equation pulsation, respectively. These two equation are modified from their original form to the inclusion of the electric charge. We found that the stability of the star decreases with the increment of the central energy density and with the increment of the amount of charge.

  2. Charge symmetry at the partonic level

    Energy Technology Data Exchange (ETDEWEB)

    Londergan, J. T.; Peng, J. C.; Thomas, A. W.

    2010-07-01

    This review article discusses the experimental and theoretical status of partonic charge symmetry. It is shown how the partonic content of various structure functions gets redefined when the assumption of charge symmetry is relaxed. We review various theoretical and phenomenological models for charge symmetry violation in parton distribution functions. We summarize the current experimental upper limits on charge symmetry violation in parton distributions. A series of experiments are presented, which might reveal partonic charge symmetry violation, or alternatively might lower the current upper limits on parton charge symmetry violation.

  3. Holographic heavy ion collisions with baryon charge

    CERN Document Server

    Casalderrey-Solana, Jorge; van der Schee, Wilke; Triana, Miquel

    2016-01-01

    We numerically simulate collisions of charged shockwaves in Einstein-Maxwell theory in anti-de Sitter space as a toy model of heavy ion collisions with non-zero baryon charge. The stress tensor and the baryon current become well described by charged hydrodynamics at roughly the same time. The effect of the charge density on generic observables is typically no larger than 15\\%. %The rapidity profile of the charge is wider than the profile of the local energy density. We find significant stopping of the baryon charge and compare our results with those in heavy ion collision experiments.

  4. Characterizing the surface charge of synthetic nanomembranes by the streaming potential method

    Science.gov (United States)

    Datta, Subhra; Conlisk, A. T.; Kanani, Dharmesh M.; Zydney, Andrew L.; Fissell, William H.; Roy, Shuvo

    2010-01-01

    The inference of the surface charge of polyethylene glycol (PEG)-coated and uncoated silicon membranes with nanoscale pore sizes from streaming potential measurements in the presence of finite electric double layer (EDL) effects is studied theoretically and experimentally. The developed theoretical model for inferring the pore wall surface charge density from streaming potential measurements is applicable to arbitrary pore cross-sectional shapes and accounts for the effect of finite salt concentration on the ionic mobilities and the thickness of the deposited layer of PEG. Theoretical interpretation of the streaming potential data collected from silicon membranes having nanoscale pore sizes, with/without pore wall surface modification with PEG, indicates that finite electric double layer (EDL) effects in the pore-confined electrolyte significantly affect the interpretation of the membrane charge and that surface modification with PEG leads to a reduction in the pore wall surface charge density. The theoretical model is also used to study the relative significance of the following uniquely nanoscale factors affecting the interpretation of streaming potential in moderate to strongly charged pores: altered net charge convection by applied pressure differentials, surface-charge effects on ionic conduction, and electroosmotic convection of charges. PMID:20462592

  5. Revealing the ultrafast charge carrier dynamics in organo metal halide perovskite solar cell materials using time resolved THz spectroscopy.

    Science.gov (United States)

    Ponseca, C S; Sundström, V

    2016-03-28

    Ultrafast charge carrier dynamics in organo metal halide perovskite has been probed using time resolved terahertz (THz) spectroscopy (TRTS). Current literature on its early time characteristics is unanimous: sub-ps charge carrier generation, highly mobile charges and very slow recombination rationalizing the exceptionally high power conversion efficiency for a solution processed solar cell material. Electron injection from MAPbI3 to nanoparticles (NP) of TiO2 is found to be sub-ps while Al2O3 NPs do not alter charge dynamics. Charge transfer to organic electrodes, Spiro-OMeTAD and PCBM, is sub-ps and few hundreds of ps respectively, which is influenced by the alignment of energy bands. It is surmised that minimizing defects/trap states is key in optimizing charge carrier extraction from these materials.

  6. Make Dark Matter Charged Again

    CERN Document Server

    Agrawal, Prateek; Randall, Lisa; Scholtz, Jakub

    2016-01-01

    We revisit constraints on dark matter that is charged under a $U(1)$ gauge group in the dark sector, decoupled from Standard Model forces. We find that the strongest constraints in the literature are subject to a number of mitigating factors. For instance, the naive dark matter thermalization timescale in halos is corrected by saturation effects that slow down isotropization for modest ellipticities. The weakened bounds uncover interesting parameter space, making models with weak-scale charged dark matter viable, even with electromagnetic strength interaction. This also leads to the intriguing possibility that dark matter self-interactions within small dwarf galaxies are extremely large, a relatively unexplored regime in current simulations. Such strong interactions suppress heat transfer over scales larger than the dark matter mean free path, inducing a dynamical cutoff length scale above which the system appears to have only feeble interactions. These effects must be taken into account to assess the viabili...

  7. Wilson loops with arbitrary charges

    CERN Document Server

    Korcyl, Piotr; Wosiek, Jacek

    2014-01-01

    We discuss how to implement, in lattice gauge theories, external charges which are not commensurate with an elementary gauge coupling. It is shown that an arbitrary, real power of a standard Wilson loop (or Polyakov line) can be defined and consistently computed in lattice formulation of non-abelian, two dimensional gauge theories. However, such an observable can excite quantum states with integer fluxes only. Since the non-integer fluxes are not in the spectrum of the theory they cannot be created, no matter which observable is chosen. Also the continuum limit of above averages does not exist unless the powers in question are in fact integer. On the other hand, a new continuum limit exists, which is rather intuitive, and where above observables make perfect sense and lead to the string tension proportional to the square of arbitrary (non necessary commensurate with gauge coupling) charge.

  8. Geometrical charged-particle optics

    CERN Document Server

    Rose, Harald H

    2009-01-01

    This reference monograph covers all theoretical aspects of modern geometrical charged-particle optics. It is intended as a guide for researchers, who are involved in the design of electron optical instruments and beam-guiding systems for charged particles, and as a tutorial for graduate students seeking a comprehensive treatment. Procedures for calculating the properties of systems with arbitrarily curved axes are outlined in detail and methods are discussed for designing and optimizing special components such as aberration correctors, spectrometers, energy filters, monochromators, ion traps, electron mirrors and cathode lenses. Also addressed is the design of novel electron optical components enabling sub-Angstroem spatial resolution and sub-0.1eV energy resolution. Relativistic motion and spin precession of the electron is treated in a concise way by employing a covariant five-dimensional procedure.

  9. Charged gravastars in higher dimensions

    Directory of Open Access Journals (Sweden)

    S. Ghosh

    2017-04-01

    Full Text Available We explore possibility to find out a new model of gravastars in the extended D-dimensional Einstein–Maxwell space–time. The class of solutions as obtained by Mazur and Mottola of a neutral gravastar [1,2] have been observed as a competent alternative to D-dimensional versions of the Schwarzschild–Tangherlini black hole. The outer region of the charged gravastar model therefore corresponds to a higher dimensional Reissner–Nordström black hole. In connection to this junction conditions, therefore we have formulated mass and the related Equation of State of the gravastar. It has been shown that the model satisfies all the requirements of the physical features. However, overall observational survey of the results also provide probable indication of non-applicability of higher dimensional approach for construction of a gravastar with or without charge from an ordinary 4-dimensional seed as far as physical ground is concerned.

  10. Charge depletion in organic heterojunction

    Science.gov (United States)

    Ng, T. W.; Lo, M. F.; Lee, S. T.; Lee, C. S.

    2012-03-01

    Until now two types of organic-organic heterojunction (OHJ) have been observed in P-N junctions formed between undoped-organic semiconductors. Charge-transfers across OHJs are either negligible or showing electron transfer from P-type to N-type materials, leading to charges accumulation near the interface. Here, we observed that junction of 4,4',4''-tris(2-methylphenyl-phenylamino)triphenylamine (m-MTDATA)/bathocuproine (BCP) show the third-behavior. Electrons in BCP (N-type) transfer to m-MTDATA (P-type), leading to depletion of mobile majority carriers near the junction. While "depletion junctions" are typical in inorganic semiconductors, there are no reports in undoped-OHJ. Formation mechanism of depletion OHJs and fundamental differences between inorganic and organic HJs are discussed.

  11. Geometrical charged-particle optics

    CERN Document Server

    Rose, Harald

    2012-01-01

    This second edition is an extended version of the first edition of Geometrical Charged-Particle Optics. The updated reference monograph is intended as a guide for researchers and graduate students who are seeking a comprehensive treatment of the design of instruments and beam-guiding systems of charged particles and their propagation in electromagnetic fields. Wave aspects are included in this edition for explaining electron holography, the Aharanov-Bohm effect and the resolution of electron microscopes limited by diffraction. Several methods for calculating the electromagnetic field are presented and procedures are outlined for calculating the properties of systems with arbitrarily curved axis. Detailed methods are presented for designing and optimizing special components such as aberration correctors, spectrometers, energy filters monochromators, ion traps, electron mirrors and cathode lenses. In particular, the optics of rotationally symmetric lenses, quadrupoles, and systems composed of these elements are...

  12. Charged particles in Titan's ionosphere

    Science.gov (United States)

    Tripathi, Sachchida

    2010-05-01

    Charged particles in Titan's ionosphere Marykutty Michael1, Sachchida Nand Tripathi1,2,3, Pratima Arya1 1Indian Institute of Technology Kanpur 2Oak Ridge Associated Universities 3NASA Goddard Space Flight Center Observations by two instruments onboard the Cassini spacecraft, Ion Neutral Mass Spectrometer (INMS) and CAssini Plasma Spectrometer (CAPS), revealed the existence of heavy hydrocarbon and nitrile species with masses of several thousand atomic mass units at altitudes of 950 - 1400 km in the atmosphere of Titan (Waite et al., 2007; Crary et al., 2009). Though these particles were believed to be molecules, they are most likely aerosols formed by the clumping of smaller molecules (Waite et al., 2009). These particles were estimated to have a density of 10-3 kg m-3 and a size of up to 256 nm. The existence of very heavy ions has also been observed by the CAPS components with a mass by charge ratio of up to 10000 (Coates et al., 2007, 2009; Sittler et al., 2009). The goal of this paper is to find out whether the so called heavy ions (or charged particles) are generated by the charge transfer of ions and electrons to the particles. The charging of these particles has been studied by using the charge balance equations that include positive ions, negative ions, electrons, neutral and charged particles. Information on the most abundant ion clusters are obtained from Vuitton et al., (2009) and Wilson and Atreya, (2004). Mass by charge ratio thus calculated will be compared with those observed by Coates et al. (2007). References: Coates AJ, et al., Discovery of heavy negative ions in Titan's ionosphere, Geophys. Res. Lett., 34:L22103, 2007. Coates AJ, et al., Heavy negative ions in titan's ionosphere: altitude and latitude dependence. Planet. Space Sci., doi:10.1016/j.pss.2009.05.009, 2009. Crary F.J., et al., Heavy ions, temperatures and winds in titan's ionosphere: Combined cassini caps and inms observations. Planet. Space Sci., doi:10.1016/j.pss.2009.09.006, 2009

  13. Invariance of the Noether charge

    CERN Document Server

    Silagadze, Z K

    2016-01-01

    Surprisingly, an interesting property of the Noether charge that it is by itself invariant under the corresponding symmetry transformation is never discussed in quantum field theory or classical mechanics textbooks we have checked. This property is also almost never mentioned in articles devoted to Noether's theorem. Nevertheless, to prove this property in the context of Lagrangian formalism is not quite trivial and the proof, outlined in this article, can constitute an useful and interesting exercise for students.

  14. The Aerospace Spacecraft Charging Document

    Science.gov (United States)

    2008-03-07

    materials is caused primarily by electrons with energies of a few hundred keV to 1.5 Hev (meg~alectron volts). These energetic electrons can penetrate thin ...Figure 13 presents a histogram of the amplitudes of those test dis- Chrges. For comparison purposes, Figure 14 presents a silar histogram of the natural...surface charging of dielectrics with respect to frame and other surface potentials include the use of transparent conduc- tive films grounded to the

  15. Screening in quantum charged systems

    Science.gov (United States)

    Martin, Ph. A.; Gruber, Ch.

    1984-07-01

    For stationary states of quantum charged systems in ν dimensions, ν>=2, it is proven that the reduced-density matrices satisfy a set of sum rules whenever the clustering is faster than |x|-(ν+l). These sum rules, describing the screening properties, are analogous to those previously derived for classical systems. For neutral quantum fluids, it is shown that the clustering cannot be faster than the decay of the force.

  16. Charging Graphene for Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jun

    2014-10-06

    Since 2004, graphene, including single atomic layer graphite sheet, and chemically derived graphene sheets, has captured the imagination of researchers for energy storage because of the extremely high surface area (2630 m2/g) compared to traditional activated carbon (typically below 1500 m2/g), excellent electrical conductivity, high mechanical strength, and potential for low cost manufacturing. These properties are very desirable for achieving high activity, high capacity and energy density, and fast charge and discharge. Chemically derived graphene sheets are prepared by oxidation and reduction of graphite1 and are more suitable for energy storage because they can be made in large quantities. They still contain multiply stacked graphene sheets, structural defects such as vacancies, and oxygen containing functional groups. In the literature they are also called reduced graphene oxide, or functionalized graphene sheets, but in this article they are all referred to as graphene for easy of discussion. Two important applications, batteries and electrochemical capacitors, have been widely investigated. In a battery material, the redox reaction occurs at a constant potential (voltage) and the energy is stored in the bulk. Therefore, the energy density is high (more than 100 Wh/kg), but it is difficult to rapidly charge or discharge (low power, less than 1 kW/kg)2. In an electrochemical capacitor (also called supercapacitors or ultracapacitor in the literature), the energy is stored as absorbed ionic species at the interface between the high surface area carbon and the electrolyte, and the potential is a continuous function of the state-of-charge. The charge and discharge can happen rapidly (high power, up to 10 kW/kg) but the energy density is low, less than 10 Wh/kg2. A device that can have both high energy and high power would be ideal.

  17. Intramolecular Charge Transfer in Arylpyrazolines

    Institute of Scientific and Technical Information of China (English)

    WANG Ming-Liang; LIU Ju-Zheng; XU Chun-Xiang

    2006-01-01

    @@ Arylpyrazoline microparticles dispersed in water are synthesized and their absorption spectra are compared with those in solution. It is found that the absorbance of pyrazoline group in solution of 5-aryl arylpyrazoline is far greater than that in solution of arylpyrazolines with no 5-aryl group. This hyperchromic effect is intensified in 5-aryl arylpyrazoline microparticles. It is indicated that intramolecular charge transfer exists between pyrazoline group and 5-aryl group and this kind of interaction is increased in their microparticles.

  18. Genetic alteration in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoo Chul; Kang, Tae Woong; Lee, Jin Oh [Korea Cancer Center Hospital of Korea Atomic Energy Research Institute, Seoul (Korea, Republic of)

    1994-12-01

    Cancer of stomach, colon and liver are a group of the most common cancer in Korea. However, results with current therapeutic modalities are still unsatisfactory. The intensive efforts have been made to understand basic pathogenesis and to find better therapeutic tools for the treatment of this miserable disease. We studied the alteration of tumor suppressor genes and oncogenes in hepatocellular carcinoma in Korea. We found that alteration of Rb gene, APC were 33 %, 13 % respectively. But alterations of oncogenes such as myc, ras and mdm2 were rarely found. Our results suggests that HBV may act as oncogenic role in hepatocarcinogenesis instead of oncogenes. 6 figs, 2 tabs. (Author).

  19. Epigenetic alterations in gastric carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    In-Seon CHOI; Tsung-Teh WU

    2005-01-01

    Gastric cancer is believed to result in part from the accumulation of multiple genetic alterations leading to oncogene overexpression and tumor suppressor loss. Epigenetic alterations as a distinct and crucial mechanism to silence a variety of methylated tissue-specific and imprinted genes, have been extensively studied in gastric carcinoma and play important roles in gastric carcinogenesis. This review will briefly discuss the basic aspects of DNA methylation and CpG island methylation, in particular the epigenetic alterations of certain critical genes implicated in gastric carcinogenesis and its relevance of clinical implications.

  20. Synchrotron radiation from massless charge

    CERN Document Server

    Gal'tsov, D V

    2015-01-01

    Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some general arguments suggest that strictly massless charge does not not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for {\\em ab initio} massless particle of zero spin. Provided $E^2\\gg eH$, the maximum in the spectrum is shown to be at $\\hbar \\omega=E/3$, and the average photon energy is $4E/9$. The normalized spectrum is universal, depending neither on $E$ nor on $H$. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Our results are consistent with the view (sup...

  1. Synchrotron radiation from massless charge

    Directory of Open Access Journals (Sweden)

    D.V. Gal'tsov

    2015-07-01

    Full Text Available Classical radiation power from an accelerated massive charge diverges in the zero-mass limit, while some authors suggest that strictly massless charge does not radiate at all. On the other hand, the regularized classical radiation reaction force, though looking odd, is non-zero and finite. To clarify this controversy, we consider radiation problem in massless scalar quantum electrodynamics in the external magnetic field. In this framework, synchrotron radiation is found to be non-zero, finite, and essentially quantum. Its spectral distribution is calculated using Schwinger's proper time technique for ab initio massless particle of zero spin. Provided E2≫eH, the maximum in the spectrum is shown to be at ħω=E/3, and the average photon energy is 4E/9. The normalized spectrum is universal, depending neither on E nor on H. Quantum nature of radiation makes classical radiation reaction equation meaningless for massless charge. Classical theory is reliable only as providing the low-frequency part of the true quantum radiation spectrum.

  2. Fully Traversable Wormholes Hiding Charge

    CERN Document Server

    Guendelman, Eduardo

    2012-01-01

    The charge-hiding effect by a wormhole, which was studied for the case where gravity/gauge-field system is self-consistently interacting with a charged lightlike brane (LLB) as a matter source, is now studied for the case of a time like brane. From the demand that no surfaces of infinite coordinate time redshift appear in the problem we are lead now to a completly traversable wormhole space, according to not only the traveller that goes through the wormhole (as was the case for the LLB), but also to a static external observer, this requires negative surface energy density for the shell sitting at the throat of the wormhole. We study a gauge field subsystem which is of a special non-linear form containing a square-root of the Maxwell term and which previously has been shown to produce a QCD-like confining gauge field dynamics in flat space-time. The condition of finite energy of the system or asymptotic flatness on one side of the wormhole implies that the charged object sitting at the wormhole throat expels a...

  3. Photon splitting in a strongly magnetized, charge-asymmetric plasma

    Directory of Open Access Journals (Sweden)

    Chistyakov M.V.

    2016-01-01

    Full Text Available The process of the photon splitting, γ → γγ, is investigated in the presence of strongly magnetized charge-asymmetric cold plasma. The dispersion properties of photons and the new polarization selection rules are obtained in such plasma. The absorption rate of the leading photon splitting channel are calculated with taking account of the photon dispersion and wave function renormalization. In addition, a comparison of the photon splitting and the Compton scattering processes is performed.

  4. Characteristics of Extreme Auroral Charging Events

    Science.gov (United States)

    Minow, Joseph I.; Willis, Emily; Parker, Linda Neergaard

    2014-01-01

    Today’s presentation describes preliminary results from a study of extreme auroral charging in low Earth orbit. Goal of study is to document characteristics of auroral charging events of importance to spacecraft design, operations, and anomaly investigations.

  5. 38 CFR 21.7076 - Entitlement charges.

    Science.gov (United States)

    2010-07-01

    ... Bill-Active Duty) Entitlement § 21.7076 Entitlement charges. (a) Overview. VA will make charges against... part of the normal term, quarter or semester, if the veteran or servicemember is enrolled for...

  6. Charged line segments and ellipsoidal equipotentials

    CERN Document Server

    Curtright, T L; Chen, X; Haddad, M J; Karayev, S; Khadka, D B; Li, J

    2016-01-01

    This is a survey of the electrostatic potentials produced by charged straight-line segments, in various numbers of spatial dimensions, with comparisons between uniformly charged segments and those having non-uniform linear charge distributions that give rise to ellipsoidal equipotentials surrounding the segments. A uniform linear distribution of charge is compatible with ellipsoidal equipotentials only for three dimensions. In higher dimensions, the linear charge density giving rise to ellipsoidal equipotentials is counter-intuitive --- the charge distribution has a maximum at the center of the segment and vanishes at the ends of the segment. Only in two dimensions is the continuous charge distribution intuitive --- for that one case of ellipsoidal equipotentials, the charge is peaked at the ends of the segment and minimized at the center.

  7. Electrostatic charges generated on aerosolisation of dispersions

    CERN Document Server

    Wang, Y

    2001-01-01

    In responding to the international community's agreement of phasing out chlorofluorocarbon (CFC) propellants by the year 2000, hydrofluoroalkane (HFA) has been chosen to replace CFCs. Intensive investigations related to the new propellant products have been carried out. Aerosol electrostatics is one of the topics investigated. To understand and subsequently control the charging processes is the motive of the research reported here. To help elucidate the complex charging process occurring naturally during atomization of liquids from pressurised Metered Dose Inhalers (pMDIs), it has been broken down into a sequence of related, simpler sub processes-drop charging, streaming current charging (coarse spray), splashing charging and fine spray charging. Our initial studies are of single drops forming at and breaking away from the tips of capillary tubes. The drop forming processes are so slow that any hydrodynamic effect can be dismissed. Then the charge on the drop is measured. It is found that the charge on water ...

  8. Complementary surface charge for enhanced capacitive deionization

    NARCIS (Netherlands)

    Gao, X.; Porada, S.; Omosebi, A.; Liu, K.L.; Biesheuvel, P.M.; Landon, J.

    2016-01-01

    Commercially available activated carbon cloth electrodes are treated using nitric acid and ethylenediamine solutions, resulting in chemical surface charge enhanced carbon electrodes for capacitive deionization (CDI) applications. Surface charge enhanced electrodes are then configured in a CDI cel

  9. Amine reactivity with charged sulfuric acid clusters

    OpenAIRE

    Bzdek, B. R.; D. P. Ridge; Johnston, M. V.

    2011-01-01

    The distribution of ionic species produced by electrospray of an ammonium sulfate solution in both positive and negative polarities is examined using Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). Positively-charged ammonium bisulfate cluster composition differs significantly from negatively-charged cluster composition. For positively-charged clusters all sulfuric acid is neutralized to bisulfate, whereas for negatively-charged clusters the degree of sulfuric acid neu...

  10. On the Preon Model with Preonic Charge

    Science.gov (United States)

    Senju, H.

    1987-05-01

    It is proposed to identify ghe recently introduced preonic charge as the source of the binding force with the magnetic charge. This identification leads to the necessary relation of composite quarks and leptons among preonic charges. The reason why the charge of quark is a third of e is under stood. The color number 3 and the preon number 3 in lepton and quark are correlated.

  11. DNA charge transport: Moving beyond 1D

    Science.gov (United States)

    Zhang, Yuqi; Zhang, William B.; Liu, Chaoren; Zhang, Peng; Balaeff, Alexander; Beratan, David N.

    2016-10-01

    Charge transport across novel DNA junctions has been studied for several decades. From early attempts to move charge across DNA double crossover junctions to recent studies on DNA three-way junctions and G4 motifs, it is becoming clear that efficient cross-junction charge migration requires strong base-to-base electronic coupling at the junction, facilitated by favorable pi-stacking. We review recent progress toward the goal of manipulating and controlling charge transport through DNA junctions.

  12. Complement Activation Alters Platelet Function

    Science.gov (United States)

    2015-12-01

    Award Number: W81XWH-12-1-0523 TITLE: Complement Activation Alters Platelet Function PRINCIPAL INVESTIGATOR: George Tsokos, M.D. CONTRACTING...Activation Alters Platelet Function 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-12-1-0523 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) George Tsokos, M.D...a decreased level of disease. Further studies will expand upon these observations better outlining the function of platelets in the injury associated

  13. Size and Charge Dependence of Ion Transport in Human Nail Plate.

    Science.gov (United States)

    Baswan, Sudhir M; Li, S Kevin; LaCount, Terri D; Kasting, Gerald B

    2016-03-01

    The electrical properties of human nail plate are poorly characterized yet are a key determinate of the potential to treat nail diseases, such as onychomycosis, using iontophoresis. To address this deficiency, molar conductivities of 17 electrolytes comprising 12 ionic species were determined in hydrated human nail plate in vitro. Cation transport numbers across the nail for 11 of these electrolytes were determined by the electromotive force method. Effective ionic mobilities and diffusivities at infinite dilution for all ionic species were determined by regression analysis. The ratios of diffusivities in nail to those in solution were found to correlate inversely with the hydrodynamic radii of the ions according to a power law relationship having an exponent of -1.75 ± 0.27, a substantially steeper size dependence than observed for similar experiments in skin. Effective diffusivities of cations in nail were 3-fold higher than those of comparably sized anions. These results reflect the strong size and charge selectivity of the nail plate for ionic conduction and diffusion. The analysis implies that efficient transungual iontophoretic delivery of ionized drugs having radii upward of 5 Å (molecular weight, ca. ≥ 340 Da) will require chemical or mechanical alteration of the nail plate. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  14. A CMOS Current Steering Neurostimulation Array With Integrated DAC Calibration and Charge Balancing.

    Science.gov (United States)

    Greenwald, Elliot; Maier, Christoph; Wang, Qihong; Beaulieu, Robert; Etienne-Cummings, Ralph; Cauwenberghs, Gert; Thakor, Nitish

    2017-04-01

    An 8-channel current steerable, multi-phasic neural stimulator with on-chip current DAC calibration and residue nulling for precise charge balancing is presented. Each channel consists of two sub-binary radix DACs followed by wide-swing, high output impedance current buffers providing time-multiplexed source and sink outputs for anodic and cathodic stimulation. A single integrator is shared among channels and serves to calibrate DAC coefficients and to closely match the anodic and cathodic stimulation phases. Following calibration, the differential non-linearity is within ±0.3 LSB at 8-bit resolution, and the two stimulation phases are matched within 0.3%. Individual control in digital programming of stimulation coefficients across the array allows altering the spatial profile of current stimulation for selection of stimulation targets by current steering. Combined with the self-calibration and current matching functions, the current steering capabilities integrated on-chip support use in fully implanted neural interfaces with autonomous operation for and adaptive stimulation under variations in electrode and tissue conditions. As a proof-of-concept we applied current steering stimulation through a multi-channel cuff electrode on the sciatic nerve of a rat.

  15. Borophene as a Promising Material for Charge-Modulated Switchable CO2 Capture.

    Science.gov (United States)

    Tan, Xin; Tahini, Hassan A; Smith, Sean C

    2017-06-14

    Ideal carbon dioxide (CO2) capture materials for practical applications should bind CO2 molecules neither too weakly to limit good loading kinetics nor too strongly to limit facile release. Although charge-modulated switchable CO2 capture has been proposed to be a controllable, highly selective, and reversible CO2 capture strategy, the development of a practical gas-adsorbent material remains a great challenge. In this study, by means of density functional theory (DFT) calculations, we have examined the possibility of conductive borophene nanosheets as promising sorbent materials for charge-modulated switchable CO2 capture. Our results reveal that the binding strength of CO2 molecules on negatively charged borophene can be significantly enhanced by injecting extra electrons into the adsorbent. At saturation CO2 capture coverage, the negatively charged borophene achieves CO2 capture capacities up to 6.73 × 10(14) cm(-2). In contrast to the other CO2 capture methods, the CO2 capture/release processes on negatively charged borophene are reversible with fast kinetics and can be easily controlled via switching on/off the charges carried by borophene nanosheets. Moreover, these negatively charged borophene nanosheets are highly selective for separating CO2 from mixtures with CH4, H2, and/or N2. This theoretical exploration will provide helpful guidance for identifying experimentally feasible, controllable, highly selective, and high-capacity CO2 capture materials with ideal thermodynamics and reversibility.

  16. Invisible Surface Charge Pattern on Inorganic Electrets

    DEFF Research Database (Denmark)

    Wang, Fei; Hansen, Ole

    2013-01-01

    We propose an easy method to pattern the surface charge of ${\\rm SiO}_{2}$ electrets without patterning the dielectric layer. By eliminating the use of metal guard electrodes, both the charge efficiency and the surface charge stability in humid environments improve. We apply the concept to a vibr...

  17. Incremental Pressing Technique in Explosive Charge

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A pressing technique has become available that might be useful for compressing granular explosives. If the height-diameter ratio of the charge is unfavorable,the high quality charge can not be obtained with the common single-action pressing. This paper presents incremental pressing technique, which can obtain the charge with higher overall density and more uniform density.

  18. 25 CFR 700.105 - Utility charges.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Utility charges. 700.105 Section 700.105 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Policies and Instructions Definitions § 700.105 Utility charges. Utility charges means the cost for...

  19. Charge conservation effects for high order fluctuations

    CERN Document Server

    Begun, Viktor

    2016-01-01

    The exact charge conservation significantly impacts multiplicity fluctuations. The result depends strongly on the part of the system charge carried by the particles of interest. Along with the expected suppression of fluctuations for large systems, charge conservation may lead to negative skewness or kurtosis for small systems.

  20. Can Like Charges Attract Each Other?

    Science.gov (United States)

    Balta, Nuri

    2012-01-01

    Electroscopes are sensitive instruments useful for investigations of static electricity. They are devices that are used for detecting whether an object is charged or uncharged. They also determine the type of charge. Their operation is based on the principle of like sign charge repulsion.