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Sample records for alpha reduced widths

  1. H I Lyman-alpha Equivalent Widths of Stellar Populations

    NASA Astrophysics Data System (ADS)

    Peña-Guerrero, María A.; Leitherer, Claus

    2013-12-01

    We have compiled a library of stellar Lyman-alpha (Lyα) equivalent widths in O and B stars using the model atmosphere codes CMFGEN and TLUSTY, respectively. The equivalent widths range from about 0 to 30 Å in absorption for early-O to mid-B stars. The purpose of this library is for the prediction of the underlying stellar Lyα absorption in stellar populations of star-forming galaxies with nebular Lyα emission. We implemented the grid of individual equivalent widths into the Starburst99 population synthesis code to generate synthetic Lyα equivalent widths for representative star formation histories. A starburst observed after 10 Myr will produce a stellar Lyα line with an equivalent width of ~ - 10 ± 4 Å in absorption for a Salpeter initial mass function. The lower value (deeper absorption) results from an instantaneous burst, and the higher value (shallower line) from continuous star formation. Depending on the escape fraction of nebular Lyα photons, the effect of stellar Lyα on the total profile ranges from negligible to dominant. If the nebular escape fraction is 10%, the stellar absorption and nebular emission equivalent widths become comparable for continuous star formation at ages of 10-20 Myr.

  2. The gravity dependence of the H-alpha width in late-type stars

    NASA Technical Reports Server (NTRS)

    Zarro, D. M.

    1985-01-01

    A theoretical gravity-scaling law for the H-alpha absorption width in late-type stars is developed. The derivation is based upon (1) the hydrostatic thickening of stellar chromospheres with decreasing surface gravity, and (2) a dependence of the H-alpha width upon opacity and Doppler width in a region subject to a chromospheric temperature rise. The scaling relation is approximately consistent with the mean gravity dependence deduced from the empirical correlation between H-alpha and Ca II K Wilson-Bappu widths. The calculations suggest that gravity variations in chromospheric-mass column density may, in addition to Doppler velocity enhancements, control the width-luminosity broadening of the H-alpha profile in late-type stars.

  3. High-resolution measurement of absolute {alpha}-decay widths in {sup 16}O

    SciTech Connect

    Wheldon, C.; Ashwood, N. I.; Barr, M.; Curtis, N.; Freer, M.; Kokalova, Tz.; Malcolm, J. D.; Spencer, S. J.; Ziman, V. A.; Faestermann, Th.; Kruecken, R.; Wirth, H.-F.; Hertenberger, R.; Lutter, R.; Bergmaier, A.

    2011-06-15

    By using a large-acceptance position-sensitive silicon detector array in coincidence with the high-resolution Munich Q3D spectrograph, unambiguous measurements have been made of the absolute {alpha}-particle decay widths from excited states in {sup 16}O* in the energy range 13.85 to 15.87 MeV. Carbon targets have been bombarded with 42-MeV {sup 6}Li beams to induce {sub 6}{sup 12}C({sub 3}{sup 6}Li, d){sub 8}{sup 16}O* reactions. The deuteron ejectiles were measured in the Q3D and the results gated by {sup 4}He+{sup 12}C breakup products detected in the silicon array, the efficiency of which was modeled using Monte Carlo simulations. By comparing total population and breakup-gated spectra, the following absolute {alpha}-decay widths have been measured with high resolution: {Gamma}{sub {alpha}}0/{Gamma}{sub tot} = 0.87{+-}0.11 (13.980 MeV), 1.04{+-}0.15 (14.302 MeV), 0.92{+-}0.10 (14.399 MeV), 0.59{+-}0.04 (14.815 MeV), 0.88{+-}0.18 (15.785 MeV), and {Gamma}{sub {alpha}}1/{Gamma}{sub tot}=1.14{+-}0.08 (14.660 MeV), 0.46{+-}0.06 (14.815 MeV).

  4. Reduced riparian zone width compromises aquatic macroinvertebrate communities in streams of southern Brazil.

    PubMed

    Moraes, Aline Bianca; Wilhelm, Andréia Emília; Boelter, Thaíse; Stenert, Cristina; Schulz, Uwe H; Maltchik, Leonardo

    2014-11-01

    Recent changes in Brazilian legislation reduced the width of riparian forest buffer needed to be preserved in private properties from 30 to 15 m or less. The consequences of these modifications can be dramatic, mainly because riparian buffer width is an important parameter for riparian forest structure and functioning. Our study assessed whether (1) macroinvertebrate family richness and Ephemeroptera, Plecoptera, and Trichoptera (EPT) family richness decrease with reduced riparian buffer width; (2) taxonomic composition and functional feeding group (FFG) composition of macroinvertebrates vary with a reduced riparian buffer width; and (3) reduced riparian buffer width similarly influence the macroinvertebrate community in different stream substrates. We selected three fragments with different riparian buffer widths (>40, <30, and <15 m) in three streams (fourth and fifth orders) in the Sinos River watershed, southern Brazil. Our results show that on all substrate types, reducing the width of the riparian buffer altered neither the macroinvertebrate richness nor EPT richness. However, EPT richness was greater in the substrates stone and gravel than leaf litter, independent of riparian buffer width. There was a significant difference in macroinvertebrate composition among riparian buffer widths. The macroinvertebrate composition and FFG differed among substrates, independent of riparian buffer width. This study showed that riparian buffer widths <15 m altered the macroinvertebrate community. A width greater than 15 m is necessary to maintain the composition and trophic conditions of macroinvertebrate families similar to those found in reference states of conservation. PMID:25052327

  5. Implications of Lyman-alpha equivalent widths in active galactic nuclei

    NASA Technical Reports Server (NTRS)

    Shields, Joseph C.; Ferland, Gary J.

    1993-01-01

    Results of photoionization calculations that examine the sensitivity of Ly-alpha emission to parameters describing the broadline clouds and incident radiation field are reported. The case of the Seyfert I galaxy NGC 5548 is considered, and good consistency is found with observed properties of the Ly-alpha zone for a cloud density of about 10 exp 11/cu cm and ratio of ionizing photon to hydrogen density near 0.2. Estimation of the cloud covering factor depends on the extrapolation of the EUV continuum. EUV cutoffs at 20 and 60 eV correspond to a range of covering factors between 0.8 and 0.5, which is larger than typically assumed in the past for luminous Seyferts. Equivalent width observations of Fairall 9 show that its continuum cannot be as soft as suggested by previous line ratio analyses and imply that its EUV continuum persists to 20 eV or more before cutting off. A method by which variability measurements can be combined with the present calculations to measure the distances to AGN, and hence the Hubble constant, is outlined.

  6. Facial Width-To-Height Ratio Relates to Alpha Status and Assertive Personality in Capuchin Monkeys

    PubMed Central

    Lefevre, Carmen Emilia; Wilson, Vanessa A. D.; Morton, F. Blake; Brosnan, Sarah F.; Paukner, Annika; Bates, Timothy C.

    2014-01-01

    Social dominance hierarchies play a pivotal role in shaping the behaviour of many species, and sex differences within these hierarchies often exist. To date, however, few physical markers of dominance have been identified. Such markers would be valuable in terms of understanding the etiology of dominant behaviour and changes in social hierarchies over time. Animals may also use such traits to evaluate the potential dominance of others relative to themselves (i.e. a physical “cue”). Facial width-to-height ratio (fWHR), for example, has been suggested as a cue to dominance in humans, with links to both dominant behaviour and the perception of dominance in other individuals. Whether this association is present in non-human animals is currently not known. Therefore, here we examine within-species links between fWHR and dominant behaviour in 64 brown capuchin monkeys (Sapajus spp.) aged between 2 and 40 years. fWHR was positively associated with alpha status and with a dimensional rating of assertive personality in both males and females. Moreover, fWHR showed significant sexual dimorphism in adults but not juveniles, suggesting a developmental change may occur during puberty. In a sub-sample, sex differences were mediated by weight, suggesting fWHR dimorphism does not exceed what would be expected by differences in body weight. This is the first report of an association between face shape and behaviour in a non-human species. Results are discussed in terms of the role that face-behaviour associations might play within capuchin societies, and the possible selective forces that might have led to the evolution of fWHR-dominance associations in humans. PMID:24705247

  7. ON THE (NON-)ENHANCEMENT OF THE Ly{alpha} EQUIVALENT WIDTH BY A MULTIPHASE INTERSTELLAR MEDIUM

    SciTech Connect

    Laursen, Peter; Duval, Florent; Oestlin, Goeran

    2013-04-01

    It has been suggested that radiative transfer effects may explain the unusually high equivalent widths (EWs) of the Ly{alpha} line, observed occasionally from starburst galaxies, especially at high redshifts. If the dust is locked up inside high-density clouds dispersed in an empty intercloud medium, the Ly{alpha} photons could scatter off of the surfaces of the clouds, effectively having their journey confined to the dustless medium. The continuum radiation, on the other hand, does not scatter, and would thus be subject to absorption inside the clouds. This scenario is routinely invoked when Ly{alpha} EWs higher than what is expected theoretically are observed, although the ideal conditions under which the results are derived usually are not considered. Here we systematically examine the relevant physical parameters in this idealized framework, testing whether any astrophysically realistic scenarios may lead to such an effect. It is found that although clumpiness indeed facilitates the escape of Ly{alpha}, it is highly unlikely that any real interstellar media should result in a preferential escape of Ly{alpha} over continuum radiation. Other possible causes are discussed, and it is concluded that the observed high EWs are more likely to be caused by cooling radiation from cold accretion and/or anisotropic escape of the Ly{alpha} radiation.

  8. Reduced Variability of Auditory Alpha Activity in Chronic Tinnitus

    PubMed Central

    Schecklmann, Martin; Kreuzer, Peter M.; Vielsmeier, Veronika; Poeppl, Timm B.; Langguth, Berthold

    2014-01-01

    Subjective tinnitus is characterized by the conscious perception of a phantom sound which is usually more prominent under silence. Resting state recordings without any auditory stimulation demonstrated a decrease of cortical alpha activity in temporal areas of subjects with an ongoing tinnitus perception. This is often interpreted as an indicator for enhanced excitability of the auditory cortex in tinnitus. In this study we want to further investigate this effect by analysing the moment-to-moment variability of the alpha activity in temporal areas. Magnetoencephalographic resting state recordings of 21 tinnitus subjects and 21 healthy controls were analysed with respect to the mean and the variability of spectral power in the alpha frequency band over temporal areas. A significant decrease of auditory alpha activity was detected for the low alpha frequency band (8–10 Hz) but not for the upper alpha band (10–12 Hz). Furthermore, we found a significant decrease of alpha variability for the tinnitus group. This result was significant for the lower alpha frequency range and not significant for the upper alpha frequencies. Tinnitus subjects with a longer history of tinnitus showed less variability of their auditory alpha activity which might be an indicator for reduced adaptability of the auditory cortex in chronic tinnitus. PMID:24967106

  9. KOLMOGOROV WIDTHS IN THE SPACE {\\tilde L}_q OF THE CLASSES {\\tilde W}_p^{\\overline \\alpha} AND {\\tilde H}_p^{\\overline \\alpha} OF PERIODIC FUNCTIONS OF SEVERAL VARIABLES

    NASA Astrophysics Data System (ADS)

    Galeev, È. M.

    1986-04-01

    The author finds the order of the Kolmogorov widths d_N({\\tilde W}_p^{\\overline \\alpha} = \\bigcap_{i=1}^m {\\tilde W}_p^{\\alpha^i}, {\\tilde L}_q) for all 1 < p,q < \\infty, where {\\tilde W}_p^\\alpha is the class of periodic functions of several variables determined by a Weyl mixed fractional derivative, and d_N({\\tilde H}_p^{\\overline \\alpha} = \\bigcap_{i=1}^m {\\tilde H}_p^{\\alpha^i},{\\tilde L}_q) for p \\ge 2 or q \\ge 2, where {\\tilde H}_p^\\alpha is the class determined by a mixed difference. Bibliography: 28 titles.

  10. Ultraviolet observations of cool stars. IV - Intensities of Lyman-alpha and Mg II in epsilon Pegasi and epsilon Eridani, and line width-luminosity correlations

    NASA Technical Reports Server (NTRS)

    Mcclintock, W.; Linsky, J. L.; Henry, R. C.; Moos, H. W.

    1975-01-01

    A spectrometer on the Copernicus satellite has been used to confirm the existence of a line width-luminosity relation for the Ly-alpha and Mg II 2800-A chromospheric emission lines in K-type stars by observation of a K2 dwarf (epsilon Eri) and a K2 supergiant (epsilon Peg). Combined with previously reported observations of lines in three K giants (alpha Boo, alpha Tau, and beta Gem), the data are consistent with an identical dependence of line width on absolute visual magnitude for the Ca II K, Ly-alpha, and Mg II 2795-A lines. Surface fluxes of Ly-alpha, Mg II 2800-A, and O V 1218-A (upper limit) for epsilon Eri, and of Mg II 2800-A for epsilon Peg are also compared with values reported previously for the three giant stars.

  11. The solar O III spectrum. II - Longer wavelengths, line widths, and the He II Lyman alpha radiation field

    NASA Technical Reports Server (NTRS)

    Kastner, S. O.; Behring, W. E.; Bhatia, A. K.

    1983-01-01

    The solar O III spectrum above 900 A is analyzed, including several visible and infrared lines which are important in nebular studies. The dependence of the line intensities on the rate of photoexcitation by He Ly-alpha is determined, and the observability of these lines in the solar spectrum is studied. The impact approximation is employed to calculate the expected line widths of the stronger solar O III lines. The photoexciting field at 304 A calculated from the observed intensities of the O III lines below 900 A (Bhatia et al., 1982) is compared with the field predicted by a recent model (Avrett et al., 1976). It is shown that additional radiation trapping must be present beyond that given by this model.

  12. Reduced Paneth cell alpha-defensins in ileal Crohn's disease.

    PubMed

    Wehkamp, Jan; Salzman, Nita H; Porter, Edith; Nuding, Sabine; Weichenthal, Michael; Petras, Robert E; Shen, Bo; Schaeffeler, Elke; Schwab, Matthias; Linzmeier, Rose; Feathers, Ryan W; Chu, Hiutung; Lima, Heriberto; Fellermann, Klaus; Ganz, Tomas; Stange, Eduard F; Bevins, Charles L

    2005-12-13

    The pathogenesis of Crohn's disease (CD), an idiopathic inflammatory bowel disease, is attributed, in part, to intestinal bacteria that may initiate and perpetuate mucosal inflammation in genetically susceptible individuals. Paneth cells (PC) are the major source of antimicrobial peptides in the small intestine, including human alpha-defensins HD5 and HD6. We tested the hypothesis that reduced expression of PC alpha-defensins compromises mucosal host defenses and predisposes patients to CD of the ileum. We report that patients with CD of the ileum have reduced antibacterial activity in their intestinal mucosal extracts. These specimens also showed decreased expression of PC alpha-defensins, whereas the expression of eight other PC products either remained unchanged or increased when compared with controls. The specific decrease of alpha-defensins was independent of the degree of inflammation in the specimens and was not observed in either CD of the colon, ulcerative colitis, or pouchitis. The functional consequence of alpha-defensin expression levels was examined by using a transgenic mouse model, where we found changes in HD5 expression levels, comparable to those observed in CD, had a pronounced impact on the luminal microbiota. Thus, the specific deficiency of PC defensins that characterizes ileal CD may compromise innate immune defenses of the ileal mucosa and initiate and/or perpetuate this disease. PMID:16330776

  13. Greater Step Widths Reduce Internal Knee Abduction Moments in Medial Compartment Knee Osteoarthritis Patients During Stair Ascent.

    PubMed

    Paquette, Max R; Klipple, Gary; Zhang, Songning

    2015-08-01

    Increased step widths have been shown to reduce peak internal knee abduction moments in healthy individuals but not in knee osteoarthritis patients during stair descent. This study aimed to assess effects of increased step widths on peak knee abduction moments and associated variables in adults with medial knee osteoarthritis and healthy older adults during stair ascent. Thirteen healthy older adults and 13 medial knee osteoarthritis patients performed stair ascent using preferred, wide, and wider step widths. Three-dimensional kinematics and ground reaction forces (GRFs) using an instrumented staircase were collected. Increased step width reduced first and second peak knee abduction moments, and knee abduction moment impulse. In addition, frontal plane GRF at time of first and second peak knee abduction moment and lateral trunk lean at time of first peak knee abduction moment were reduced with increased step width during stair ascent in both groups. Knee abduction moment variables were not different between knee osteoarthritis patients and healthy controls. Our findings suggest that increasing step width may be an effective simple gait alteration to reduce knee abduction moment variables in both knee osteoarthritis and healthy adults during stair ascent. However, long term effects of increasing step width during stair ascent in knee osteoarthritis and healthy adults remain unknown. PMID:25781222

  14. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

    SciTech Connect

    Myra, J. R.; Russell, D. A.; D’Ippolito, D. A.; Ahn, J.-W.; Maingi, R.; Maqueda, R. J.; Lundberg, D. P.; Stotler, D. P.; Zweben, S. J.; Boedo, J.; Umansky, M.

    2011-01-01

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from the simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat flux width for the low power H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL heat flux width observed experimentally in higher power discharges. Intermittent separatrix spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping vs. emission are discussed.

  15. Reduced model simulations of the scrape-off-layer heat-flux width and comparison with experiment

    DOE PAGESBeta

    Myra, J. R.; Russell, D. A.; D’Ippolito, D. A.; Ahn, J.-W.; Maingi, R.; Maqueda, R. J.; Lundberg, D. P.; Stotler, D. P.; Zweben, S. J.; Boedo, J.; et al

    2011-01-01

    Reduced model simulations of turbulence in the edge and scrape-off-layer (SOL) region of a spherical torus or tokamak plasma are employed to address the physics of the scrape-off-layer heat flux width. The simulation model is an electrostatic two-dimensional fluid turbulence model, applied in the plane perpendicular to the magnetic field at the outboard midplane of the torus. The model contains curvature-driven-interchange modes, sheath losses, and both perpendicular turbulent diffusive and convective (blob) transport. These transport processes compete with classical parallel transport to set the SOL width. Midplane SOL profiles of density, temperature and parallel heat flux are obtained from themore » simulation and compared with experimental results from the National Spherical Torus Experiment (NSTX) to study the scaling of the heat flux width with power and plasma current. It is concluded that midplane turbulence is the main contributor to the SOL heat flux width for the low power H-mode discharges studied, while additional physics is required to explain the plasma current scaling of the SOL heat flux width observed experimentally in higher power discharges. Intermittent separatrix spanning convective cells are found to be the main mechanism that sets the near-SOL width in the simulations. The roles of sheared flows and blob trapping vs. emission are discussed.« less

  16. Anomalous fluctuations of s-wave reduced neutron widths of 192,194Pt resonances

    SciTech Connect

    Koehler, Paul Edward; Becvar, F.; Krticka, Milan; Harvey, John A; Guber, Klaus H

    2010-01-01

    We obtained an unprecedentedly large number of s-wave neutron widths through R-matrix analysis of neutron cross-section measurements on enriched Pt samples. Careful analysis of these data rejects the validity of the Porter-Thomas distribution with a statistical significance of at least 99.997%.

  17. A pulse width modulated picket fence pulser to reduce accelerator start-up transients

    SciTech Connect

    Reass, William A; Balmes, Anthony A; Bradley, Joseph T; Netz, Dana; Sandoval, Jacob B

    2010-01-01

    This paper describes a solid state modulator used to control the input beam to the Los Alamos Neutron Science Center 'LANSCE' 800 MeV accelerator. This electrostatic Ground Level Deflector (GLD) chops the beam after the 750 keV injection energy. Two GLD's are utilized, one for the 'H+' beam and another for the 'H-' beam. These modulators are mounted on the vacuum beam pipe and directly operate sets of deflection plates. To minimize the accelerator beam start up transients, the beam is let into the accelerator cavity structures by a pulse width modulated picket fence operating between 0 and 12 kV. As the deflection plate structure appears as a capacitive load, a totem-pole switching network is utilized to facilitate rise and fall times of {approx}50 ns that is able to sink and source current to minimize beam induced sidewall activation. This paper will describe the system design and provides operational results as now presently utilized on the LANSCE accelerator system.

  18. Does formate reduce alpha-ketoglutarate and ammonia to glutamate?

    NASA Technical Reports Server (NTRS)

    Maughan, Q.; Miller, S. L.; Bada, J. L. (Principal Investigator)

    1999-01-01

    The reported reduction of alpha-ketoglutarate and ammonia by formate is much slower than described (Morowitz et al., 1995). The formate reduction if any is small under these conditions. Glutamate is produced from a reduction by a second molecule of alpha-ketoglutarate involving an oxidative decarboxylation.

  19. Width measurement of the {sup 6}Li{sub 4.31} state by the {sup 7}Li({sup 3}He, {alpha}d){alpha} reaction

    SciTech Connect

    Arena, N.; Cavallaro, S.; D`Agostino, P.; D`Arrigo, A.; Fazio, G.; Giardina, G.; Sacchi, M.; Eremin, N.V.; Klochko, T.U.; Lombardi, M.

    1995-02-01

    The J{sup {pi}} = 2{sup +}, T = 0 {sup 6}Li state at E{sub x} = 4.31 MeV was populated by the {sup 7}Li({sup 3}He, {alpha}d){alpha} reaction performed at 4, 5, and 6 MeV {sup 3}He incident energies. The values obtained for {Gamma}({sup 6}Li{sub 4.31}) were compared with those deduced from the above reaction at E({sup 3}He) = 2.5 MeV. In contrast to the findings of other authors, no dependence of the above parameter on incident energy was observed. 23 refs., 1 fig., 2 tabs.

  20. Neonatal Mandibular Distraction Osteogenesis Reduces Cleft Palate Width and Lengthens Soft Palate, Influencing Palatoplasty in Patients With Pierre Robin Sequence.

    PubMed

    Collares, Marcus V M; Duarte, Daniele W; Sobral, Davi S; Portinho, Ciro P; Faller, Gustavo J; Fraga, Mariana M

    2016-07-01

    The aim of this study was to evaluate the influence of neonatal mandibular distraction osteogenesis (MDO) on cleft dimensions and on early palatoplasty outcomes in patients with Pierre Robin Sequence (PRS). In a prospective cohort study that enrolled 24 nonsyndromic patients with PRS, 12 submitted to the MDO group and 12 patients not treated (non-MDO group), the authors compared patients for cleft palate dimensions through 7 morphometric measurements at the moment of palatoplasty and for early palatoplasty outcomes. At palatoplasty, the MDO group presented a significant shorter distance between the posterior nasal spines (PNS-PNS, P < 0.001) and between uvular bases (UB-UB, P < 0.001), representing a reduction in cleft palate width. They also had significant soft palate lengthening represented by a larger distance between UB and retromolar space (UB-RM, P < 0.001) and UB and PNS (UB-PNS, P = 0.014). Their UB moved away from the posterior wall of the nasopharynx (UB-NPH, P < 0.001). The MDO group had a length of operative time significantly shorter (P < 0.001) and no early palatoplasty complications compared with the non-MDO group. In conclusion, MDO acted as an orthopedic procedure that reduced cleft palate width and elongated the soft palate in patients with PRS. These modifications enabled a reduction of around 11% in the length of operative time of palatoplasty (P < 0.001). PMID:27315309

  1. Reducing, by pulse width modulation, the curing temperature of a prototype high-power LED light curing unit.

    PubMed

    Huang, Ta-Ko; Hung, Chun-Cheng; Tsai, Chi-Cheng

    2006-06-01

    Third-generation LEDs have high irradiance and efficiency, but the associated temperature rise is potentially hazardous to the pulp of teeth. We evaluated, during composite polymerization, the irradiance and temperature rise of a prototype high-power LED light curing unit (LCU) with optimal pulse width modulation (PWM), and then compared the results with four off-the-shelf high-power LCUs. A cavity was prepared in a tooth, and a composite resin layer was applied and cured. For each LCU, the irradiance and temperature changes at the pulp-dentin junction were measured. Microhardness (Vickers hardness) of cured composite samples was measured for each LCU. Our prototype had a final temperature of 36.4 +/- 1.3 degrees C and irradiance of 1,182 +/- 1 mW/cm2. The unit with the highest temperature had a temperature of 48.7 +/- 1.2 degrees C and an irradiance of 1,194 +/- 1 mW/cm2. Based on the results of the present study, it was shown that PWM technology reduced the curing temperature while retaining the polymerization effectiveness of a high-power LED LCU. PMID:16916235

  2. Laminin alpha1 chain reduces muscular dystrophy in laminin alpha2 chain deficient mice.

    PubMed

    Gawlik, Kinga; Miyagoe-Suzuki, Yuko; Ekblom, Peter; Takeda, Shin'ichi; Durbeej, Madeleine

    2004-08-15

    Laminin (LN) alpha2 chain deficiency in humans and mice leads to severe forms of congenital muscular dystrophy (CMD). Here, we investigated whether LNalpha1 chain in mice can compensate for the absence of LNalpha2 chain and prevent the development of muscular dystrophy. We generated mice expressing a LNalpha1 chain transgene in skeletal muscle of LNalpha2 chain deficient mice. LNalpha1 is not normally expressed in muscle, but the transgenically produced LNalpha1 chain was incorporated into muscle basement membranes, and normalized the compensatory changes of expression of certain other laminin chains (alpha4, beta2). In 4-month-old mice, LNalpha1 chain could fully prevent the development of muscular dystrophy in several muscles, and partially in others. The LNalpha1 chain transgene not only reversed the appearance of histopathological features of the disease to a remarkable degree, but also greatly improved health and longevity of the mice. Correction of LNalpha2 chain deficiency by LNalpha1 chain may serve as a paradigm for gene therapy of CMD in patients. PMID:15213105

  3. 5Alpha-Reduced Steroids Are Major Metabolites in the Early Equine Embryo Proper and Its Membranes.

    PubMed

    Raeside, James I; Christie, Heather L; Betteridge, Keith J

    2015-09-01

    Steroid production and metabolism by early conceptuses are very important for the establishment and maintenance of pregnancy in horses. Our earlier work suggested the possible formation of 5alpha-reduced steroids in equine conceptuses. We have now demonstrated the formation of 5alpha-reduced metabolites of androstenedione, testosterone, and progesterone by the embryo and its membranes. A total of 44 conceptuses were collected from 26 mares between 20 and 31 days of pregnancy. Tissues from the embryo proper and from the separated components of the conceptus (bilaminar and trilaminar trophoblast, allantois) were incubated with tritium-labeled substrates. 5Alpha-reduced metabolites (5alpha-dihydro- and 3beta,5alpha-tetrahydro- steroids) as radiolabeled products were identified from a series of chromatographic steps using four solvent systems for high-performance liquid chromatography. Use of a 5alpha-reductase inhibitor confirmed the metabolites were indeed 5alpha-reduced steroids. For the embryo, the only products from androstenedione were 5alpha-dihydroandrostenedione and 3beta,5alpha-tetrahydroandrostenedione, with no evidence of more polar metabolites; there was some 3beta,5alpha-tetrahydrotestosterone but no 5alpha-dihydrotestosterone from testosterone, and formation of androstenedione was followed by the production of 5alpha-dihydroandrostenedione and 3beta,5alpha-tetrahydroandrostenedione. The major 5alpha-reduced product from progesterone was 3beta,5alpha-tetrahydroprogesterone, with lesser amounts of 5alpha-dihydroprogesterone. For the membranes, reductions to tetrahydro, 5alpha-reduced steroids were prominent in most instances, but also present were considerable amounts of products more polar than the substrates. The well-recognized activity of some 5alpha-reduced steroids--for example, 5alpha-dihydrotestosterone in male sexual differentiation--provokes interest in their even earlier appearance, as seen in this study, and suggests a possible role for them in

  4. Alpha and gamma band oscillations index differential processing of acoustically reduced and full forms.

    PubMed

    Drijvers, Linda; Mulder, Kimberley; Ernestus, Mirjam

    2016-02-01

    Reduced forms like yeshay for yesterday often occur in conversations. Previous behavioral research reported a processing advantage for full over reduced forms. The present study investigated whether this processing advantage is reflected in a modulation of alpha (8-12Hz) and gamma (30+Hz) band activity. In three electrophysiological experiments, participants listened to full and reduced forms in isolation (Experiment 1), sentence-final position (Experiment 2), or mid-sentence position (Experiment 3). Alpha power was larger in response to reduced forms than to full forms, but only in Experiments 1 and 2. We interpret these increases in alpha power as reflections of higher auditory cognitive load. In all experiments, gamma power only increased in response to full forms, which we interpret as showing that lexical activation spreads more quickly through the semantic network for full than for reduced forms. These results confirm a processing advantage for full forms, especially in non-medial sentence position. PMID:26878718

  5. Experimental investigation of heat transfer augmentation inside double pipe heat exchanger equipped with reduced width twisted tapes inserts using polymeric nanofluid

    NASA Astrophysics Data System (ADS)

    Hazbehian, Mohammad; Maddah, Heydar; Mohammadiun, Hamid; Alizadeh, Mostafa

    2016-01-01

    In this study, we report a further enhancement in heat transfer coefficients of base fluid in combination with structural modifications of tape inserts. Polyvinyl Alcohol and TiO2 with mean diameter of 15 nm were chosen as base fluid and nano-particles, respectively. The experiments are carried out in plain tube with four longitudinal internal fins and reduced width twisted tape (RWTT) inserts of twist ratio varying form 2-5 and width of 12-16. Experiments are undertaken to determine heat transfer coefficients and friction factor of TiO2/PVA nanofluid up to 2.0 % volume concentration at an average temperature of 30 °C. The investigations are undertaken in the Reynolds number range of 800-30,000 for flow in tubes and with tapes of different width length ratios. The experiments was verified with well-known correlations. The average Nusselt number and friction factor in the tube fitted with the full-length twisted tapes at y/w = 3.0, and 5.0, are respectively 50-130, and 30-95 % higher than those in the plain tube; 90-220 and 100-270 % when the working fluid is nanofluid, respectively. For the reduced width twisted tapes, the heat transfer rate is decreased with decreasing tapes width. The average Nusselt numbers in the tube fitted with the RWTT of 16, 14 and 12 are respectively, 210-390, 190-320 and 170-290 % of that in the plain tube. With the similar trend mentioned above, RWTT with higher width length yield higher thermal enhancement factor in comparison with smaller width. The use of RWTT led to the highest thermal performance factor up to 1.75. Maximum thermal performance factor which was obtained belonged to twists with twist ratio of 2 and width of 16 with φ = 0.5 % and Reynolds number range of 800-30,000.

  6. Reduced serum levels of 1 alpha,25-dihydroxyvitamin D during long-term total parenteral nutrition.

    PubMed

    Klein, G L; Horst, R L; Norman, A W; Ament, M E; Slatopolsky, E; Coburn, J W

    1981-05-01

    Painful bone disease, characterized by patchy osteomalacia and inactive bone, can develop in patients treated with total parenteral nutrition for more than 3 months. Serum levels of 1 alpha,25-dihydroxyvitamin D (1 alpha, 25(OH)2D), 24,25-dihydroxyvitamin D and 25-hydroxyvitamin D were measured in seven adults and five children treated with parenteral nutrition for 9 to 60 months. Serum levels of 1 alpha, 25(OH)2D were markedly reduced, while levels of 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D were normal. Serum calcium and phosphorus levels were normal or slightly increased, and immunoreactive parathyroid hormone levels were normal or low. Renal function was normal or minimally reduced. Skeletal symptoms disappeared and serum 1 alpha, 25(OH)2D levels rose to normal in one patient when nutrient infusions were discontinued for 6 weeks. Removal of calcium from the nutrient solution for 2 to 4 days was associated with no change in serum 1 alpha, 25(OH)2D in two patients. The cause of the reduction in serum levels of 1 alpha, 25(OH)2D and its role in the pathogenesis of bone disease in these patients remain uncertain. PMID:6786151

  7. Inhibition of protein synthesis by imexon reduces HIF-1alpha expression in normoxic and hypoxic pancreatic cancer cells.

    PubMed

    Samulitis, Betty K; Landowski, Terry H; Dorr, Robert T

    2009-02-01

    Hypoxia-inducing factor-1 alpha (HIF-1alpha), is a major survival factor for tumor cells growing in a low oxygen environment. The anti-cancer agent imexon binds thiols and causes accumulation of reactive oxygen species (ROS) in pancreatic cancer cells. Unlike many cytotoxic agents, imexon is equi-cytotoxic in human MiaPaCa-2 and Panc-1 cells grown in normoxic (21% O(2)) and hypoxic (1% O(2)) conditions. Western blot analyses of imexon-treated cells demonstrated that imexon reduces HIF-1alpha protein levels in both normoxic and hypoxic conditions in a time- and concentration-dependant fashion. Gemcitabine did not similarly affect HIF-1alpha levels. Imexon did not reduce transcription of new HIF-1alpha mRNA, but did reduce the synthesis of new proteins, including HIF-1alpha, measured by (35)S methionine/cysteine (Met/Cys) incorporation. Concurrently, the half-life of existing HIF-1alpha protein was increased by imexon, in association with a marked inhibition of chymotryptic activity in the 20S proteasome. The inhibition of HIF-1alpha translation was not specific, rather it was part of a general decrease in protein translation caused by imexon. This inhibitory effect on translation did not involve phosphorylation of eukaryotic initiation factor-2alpha (eIF-2alpha) and was not closely correlated to cell growth inhibition by imexon, suggesting that mechanisms other than protein synthesis inhibition contribute to the drug's cytotoxic effects. In summary, imexon blocks the translation of new proteins, including HIF-1alpha, and this effect overcomes an increase in the stability of preformed HIF-1alpha due to proteasome inhibition by imexon. Because net HIF-1alpha levels are reduced by imexon, combination studies with other drugs affected by HIF-1alpha survival signaling are warranted. PMID:18607542

  8. A Ly{alpha} EMITTER WITH AN EXTREMELY LARGE REST-FRAME EQUIVALENT WIDTH OF {approx}900 A AT z = 6.5: A CANDIDATE POPULATION III-DOMINATED GALAXY?

    SciTech Connect

    Kashikawa, Nobunari; Hayashi, Masao; Iye, Masanori; Nagao, Tohru; Ota, Kazuaki; Toshikawa, Jun; Ishizaki, Yoshifumi; Shibuya, Takatoshi; Egami, Eiichi; Jiang, Linhua; Ly, Chun; Malkan, Matthew A.; Matsuda, Yuichi; Shimasaku, Kazuhiro; Taniguchi, Yoshiaki; Shioya, Yasuhiro

    2012-12-20

    We have identified a very interesting Ly{alpha} emitter (LAE), whose Ly{alpha} emission line has an extremely large observed equivalent width of EW{sub 0} = 436{sup +422}{sub -{sub 149}} A, which corresponds to an extraordinarily large intrinsic rest-frame equivalent width of EW{sup int}{sub 0} = 872{sup +844}{sub -{sub 298}} A after the average intergalactic absorption correction. The object was spectroscopically confirmed to be a real LAE by its apparent asymmetric Ly{alpha} line profile detected at z = 6.538. The continuum emission of the object was definitely detected in our deep z'-band image; thus, its EW{sub 0} was reliably determined. Follow-up deep near-infrared spectroscopy revealed emission lines of neither He II {lambda}1640 as an apparent signature of Population III (Pop III) nor C IV {lambda}1549 as proof of an active nucleus. No detection of the short-lived He II {lambda}1640 line is not necessarily inconsistent with the interpretation that the underlying stellar population of the object is dominated by Pop III. We found that the observed extremely large EW{sub 0} of the Ly{alpha} emission and the upper limit on the EW{sub 0} of the He II {lambda}1640 emission can be explained by population synthesis models favoring a very young age less than 2-4 Myr and massive metal-poor (Z < 10{sup -5}) or even metal-free stars. The observed large EW{sub 0} of Ly{alpha} is insufficiently explained by Population I/II synthesis models with Z {>=} 10{sup -3}. However, we cannot conclusively rule out the possibility that this object is composed of a normal stellar population with a clumpy dust distribution, which could enhance the Ly{alpha} EW{sub 0}, though its significance is still unclear.

  9. Alpha-defensins 1-3 release by dendritic cells is reduced by estrogen

    PubMed Central

    2011-01-01

    Background During pregnancy the immune system of the mother must protect any activation that may negatively affect the fetus. Changes in susceptibility to infection as well as resolution of some autoimmune disorders represent empirical evidence for pregnancy related alterations in immunity. Sex hormones reach extremely high levels during pregnancy and have been shown to have direct effects on many immune functions including the antiviral response of dendritic cells. Among the immunologically active proteins secreted by monocyte derived DCs (MDDC) are the alpha-defensins 1-3. This family of cationic antimicrobial peptides has a broad spectrum of microbicidal activity and has also been shown to link innate to adaptive immunity by attracting T cells and immature DCs, which are essential for initiating and polarizing the immune response. Methods We compare culture-generated monocyte derived DCs (MDDCs) with directly isolated myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs) and measure their alpha-defensins 1-3 secretion by ELISA both, in basal situations and after hormone (E2 or PG) treatments. Moreover, using a cohort of pregnant women we isolated mDCs from blood and also measure the levels of these anti-microbial peptides along pregnancy. Results We show that mDCs and pDCs constitutively produce alpha-defensins 1-3 and at much higher levels than MDDCs. Alpha-defensins 1-3 production from mDCs and MDDCs but not pDCs is inhibited by E2. PG does not affect alpha-defensins 1-3 in any of the populations. Moreover, alpha-defensins 1-3 production by mDCs was reduced in the later stages of pregnancy in 40% of the patients. Conclusions Here, we demonstrate that mDCs and pDCs secrete alpha-defensins 1-3 and present a novel effect of E2 on the secretion of alpha-defensins 1-3 by dendritic cells. PMID:21861873

  10. Foam-stabilizing effects and cling formation patterns of iso-alpha-acids and reduced iso-alpha-acids in lager beer.

    PubMed

    Kunimune, Takeshi; Shellhammer, Thomas H

    2008-09-24

    Foam-stabilizing properties and cling formation patterns of iso-alpha-acids and reduced iso-alpha-acids were investigated using an unhopped lager beer. Unhopped beer was dosed with iso-alpha-acid (Iso), rho-iso-alpha-acid (Rho), tetrahydro-iso-alpha-acid (Tetra), and hexahydro-iso-alpha-acid (Hexa), separately, over a range of concentrations from 2 to 10 ppm. A uniform foam was created by Inpack 2000 Flasher Head and was measured by a NIBEM Foam Stability Tester (NIBEM-TPH) followed by a NIBEM Cling Meter (NIBEM-CLM) to determine the relationship between the concentration and NIBEM-30 and the cling formation ability of each compound. The foam-stabilizing power was determined to be Tetra, Hexa, Iso, and Rho from the strongest to weakest. Linear regression models were created using the NIBEM-TPH data set, and on the basis of 95% confidence intervals, the foam stability of Tetra or Hexa became significantly larger than that of Iso when 2.4 or 4.2 ppm of Tetra or Hexa was used as a replacement for Iso, respectively. Cling formation patterns could be categorized into three groups: "ring", "mesh", and "powdery". The control beer had the lowest foam stability and did not yield any foam cling. PMID:18729457

  11. The REDUCE trial: chemoprevention in prostate cancer using a dual 5alpha-reductase inhibitor, dutasteride.

    PubMed

    Musquera, Mireia; Fleshner, Neil E; Finelli, Antonio; Zlotta, Alexandre R

    2008-07-01

    Dutasteride, a dual 5alpha-reductase inhibitor, is used in the treatment of benign prostatic hyperplasia (BPH). It reduces serum prostate-specific antigen levels by approximately 50% at 6 months and total prostate volume by 25% after 2 years. Randomized placebo-controlled trials in BPH patients have shown the efficacy of dutasteride in symptomatic relief, improvements in quality of life and peak urinary flow rate. Side effects occurring with dutasteride are decreased libido, erectile dysfunction, ejaculation disorders and gynecomastia. Preliminary data from placebo-controlled BPH trials have shown a decrease in the detection of prostate cancer in patients treated with dutasteride, although these studies were not designed to look at this issue. Dutasteride differs from finasteride in that it inhibits both isoenzymes of 5alpha-reductase, type I and type II. The landmark Prostate Cancer Prevention Trial at the end of the 7-year study demonstrated a 24.8% reduction in the incidence of prostate cancer in the finasteride group compared with placebo. However, a 25.5% increase in the prevalence of high-grade Gleason tumors has been observed, the clinical significance of which has been debated. Preliminary data suggest a decrease in prostate cancer incidence in dutasteride-treated patients and demonstrate type I alphareductase enzyme expression in prostate cancer. As a result, dutasteride is being investigated for prostate cancer prevention in the ongoing Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, which is discussed here. PMID:18588452

  12. Measurement of the 4. 8-MeV /sup 9/B state width by the reaction /sup 10/B(/sup 3/He,. cap alpha. )/sup 9/B(. cap alpha. ) /sup 5/Li at E( /sup 3/He) = 2. 3 and 5. 0 MeV

    SciTech Connect

    Arena, N.; Cavallaro, S.; Fazio, G.; Giardina, G.; Italiano, A.; Mezzanares, F.

    1986-10-13

    The analog of the 4.7-MeV state of the /sup 9/Be nucleus has been observed in its mirror /sup 9/B by the reaction /sup 10/B(/sup 3/He, ..cap alpha..)/sup 9/B(..cap alpha..) /sup 5/Li (g.s.) at E( /sup 3/He) = 2.3 and 5.0 MeV. The excitation energy and width of the state have been deduced. The value of 1.5 +- 0.3 MeV found for the width is in line with the value deduced by the reaction /sup 7/Li(/sup 3/He,n) /sup 9/B, but it is larger by a factor of about 4 than the one measured by the proton following the ..beta../sup +/ decay of the /sup 9/C nucleus.

  13. Local delivery of soluble TNF-alpha receptor 1 gene reduces infarct size following ischemia/reperfusion injury in rats.

    PubMed

    Sugano, Masahiro; Hata, Tomoji; Tsuchida, Keiko; Suematsu, Nobuhiro; Oyama, Jun-Ichi; Satoh, Shinji; Makino, Naoki

    2004-11-01

    Apoptosis in the myocardium is linked to ischemia/reperfusion injury, and TNF-alpha induces apoptosis in cardiomyocytes. A significant amount of TNF-alpha is detected after ischemia and reperfusion. Soluble TNF-alpha receptor 1 (sTNFR1) is an extracellular domain of TNF-alpha receptor 1 and is an antagonist to TNF-alpha. In the present study, we examined the effects of sTNFR1 on infarct size in acute myocardial infarction (AMI) following ischemia/reperfusion. Male Wistar rats were subjected to left coronary artery (LCA) ligation. After 30 min of LCA occlusion, the temporary ligature on the LCA was released and blood flow was restored. Immediately after reperfusion, a total of 200 microg of sTNFR1 or LacZ plasmid was injected into three different sites of the left ventricular wall. At 6 h, 1 and 2 days after reperfusion, the TNF-alpha bioactivity in the myocardium was significantly higher in rats receiving LacZ plasmid than in sham-operated rats, whereas sTNFR1 plasmid significantly suppressed the increase in the TNF-alpha bioactivity. The sTNFR1 plasmid significantly reduced DNA fragmentation and caspase activity compared to the LacZ plasmid. Finally, the sTNFR1 expression-plasmid treatment significantly reduced the area of myocardial infarction at 2 days after ischemia/reperfusion compared to LacZ plasmid. In conclusion, the TNF-alpha bioactivity in the heart increased from the early stage of ischemia/reperfusion, and this increase was thought to contribute in part to the increased area of myocardial infarction. Suppression of TNF-alpha bioactivity with the sTNFR1 plasmid reduced the infarct size in AMI following ischemia and reperfusion. PMID:15646033

  14. Thalidomide treatment reduces tumor necrosis factor alpha production and enhances weight gain in patients with pulmonary tuberculosis.

    PubMed Central

    Tramontana, J. M.; Utaipat, U.; Molloy, A.; Akarasewi, P.; Burroughs, M.; Makonkawkeyoon, S.; Johnson, B.; Klausner, J. D.; Rom, W.; Kaplan, G.

    1995-01-01

    BACKGROUND: The monocyte-derived cytokine, tumor necrosis factor alpha (TNF alpha), is essential for host immunity, but overproduction of this cytokine may have serious pathologic consequences. Excess TNF alpha produced in pulmonary tuberculosis may cause fevers, weakness, night sweats, necrosis, and progressive weight loss. Thalidomide (alpha-N-phthalimidoglutarimide) has recently been shown to suppress TNF alpha production by human monocytes in vitro and to reduce serum TNF alpha in leprosy patients. We have therefore conducted a two-part placebo-controlled pilot study of thalidomide in patients with active tuberculosis to determine its effects on clinical response, immune reactivity, TNF alpha levels, and weight. MATERIALS AND METHODS: 30 male patients with active tuberculosis, either human immunodeficiency virus type 1 positive (HIV-1+) or HIV-1-, received thalidomide or placebo for single or multiple 14 day cycles. Toxicity of the study drug, delayed type hypersensitivity (DTH), cytokine production, and weight gain were evaluated. RESULTS: Thalidomide treatment was well tolerated, without serious adverse events. The drug did not adversely affect the DTH response to purified protein derivative (PPD), total leukocyte, or differential cell counts. TNF alpha production was significantly reduced during thalidomide treatment while interferon-gamma (IFN gamma) production was enhanced. Daily administration of thalidomide resulted in a significant enhancement of weight gain. CONCLUSIONS: The results indicate that thalidomide is well tolerated by patients receiving anti-tuberculosis therapy. Thalidomide treatment reduces TNF alpha production both in vivo and in vitro and is associated with an accelerated weight gain during the study period. PMID:8521296

  15. Failure of isolated rat tibial periosteal cells to 5 alpha reduce testosterone to 5 alpha-dihydrotestosterone

    SciTech Connect

    Turner, R.T.; Bleiberg, B.; Colvard, D.S.; Keeting, P.E.; Evans, G.; Spelsberg, T.C. )

    1990-07-01

    Periosteal cells were isolated from tibiae of adult male rats after collagenase treatment. Northern blot analysis of total cytoplasmic RNA extracted from the isolated periosteal cells was positive for expression of genes encoding the osteoblast marker proteins osteocalcin (BGP) and pre-pro-alpha 2(I) chain of type 1 precollagen. The isolated periosteal cells were incubated with 1 nM (3H)testosterone (({sup 3}H)T) for up to 240 minutes and the reaction products separated by high-performance liquid chromatography. ({sup 3}H)5 alpha-dihydrotestosterone (({sup 3}H)DHT) was not detected in extracts of periosteal cell incubations. In contrast, ({sup 3}H)DHT was produced in a time-dependent manner by cells from seminal vesicles. These results suggest that testosterone 5 alpha-reductase activity is not expressed by osteoblasts in rat tibial periosteum and that the anabolic effects of androgens in this tissue are not mediated by locally produced DHT.

  16. Intranasal application of alpha interferon reduces morbidity associated with low pathogenic avian influenza infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Type I interferons, including interferon alpha (IFN-alpha), are expressed rapidly after viral infection, and represent a first line of defense initiated by the innate immune response. Following infection of chickens with avian influenza virus (AIV), transcription of IFN-alpha is quickly up regulate...

  17. Radiation brain injury is reduced by the polyamine inhibitor [alpha]-difluoromethylornithine

    SciTech Connect

    Fike, J.R.; Seilhan, T.M.; Gobbel, G.T. ); Marton, L.J. )

    1994-04-01

    [alpha]-difluoromethylornithine (DFMO) was used to reduce [sup 125]I-induced brain injury in normal beagle dogs. Different DFMO doses and administration schedules were used to determine if the reduction in brain injury was dependent on dose and/or dependent upon when the drug was administered relative to the radiation treatment. Doses of DMFO of 75 mg/kg/day and 37.5 mg/kg/day given 2 days before, during and for 14 days after irradiation reduced levels of putrescine (PU) in the cerebrospinal fluid relative to controls. Volume of edema was significantly reduced by 75 mg/kg/day of DFMO before, during and after irradiation and by the same dose when the drug was started immediately after irradiation. A reduction in edema volume after 37.5 mg/kg/day of DFMO before, during and after irradiation was very near significance. Ultrafast CT studies performed on dogs that received a DFMO dose of 75 mg/kg/day before, during and after irradiation suggested that the reduce edema volume was associated with reduced vascular permeability. Volume of necrosis and volume of contrast enhancement (breakdown of the blood-brain barrier) were significantly lower than controls only after a DFMO dose of 75 mg/kg/day before, during and after irradiation. These latter data, coupled with the findings relative to edema, suggest that different mechanisms may be involved with respect to the effects of DFMO on brain injury, or that the extents of edema, necrosis and breakdown of the blood-brain barrier may depend upon different levels of polyamine depletion. The precise mechanisms by which DFMO exerts the effects observed here need to be determined. 41 refs., 5 figs.

  18. Age-Related Increases in Basal Ganglia Glutamate are Associated with TNF-Alpha, Reduced Motivation and Decreased Psychomotor Speed During IFN-alpha Treatment: Preliminary Findings

    PubMed Central

    Haroon, Ebrahim; Felger, Jennifer C.; Woolwine, Bobbi J.; Chen, Xiangchuan; Parekh, Samir; Spivey, James; Hu, Xiaoping; Miller, Andrew H.

    2014-01-01

    Inflammation-induced alterations in central nervous system (CNS) metabolism have focused on glutamate. At excessive concentrations, glutamate is toxic to glia and neurons, and inflammatory cytokines have been shown to influence glutamate metabolism by blocking glutamate reuptake and increasing glutamate release. Increased glutamate has also been found in depression, a disorder associated with increased inflammation. Data by our group have shown increased glutamate as measured by magnetic resonance spectroscopy (MRS) in basal ganglia and dorsal anterior cingulate cortex of patients administered the inflammatory cytokine interferon (IFN)-alpha. Given data that increasing age is associated with an exaggerated CNS inflammatory response, we examined whether older age (>55 years) would be associated with a greater IFN-alpha-induced increase in CNS glutamate. Using a longitudinal design, 31 patients with hepatitis C virus (HCV) underwent MRS, blood sampling for inflammatory markers, and behavioral assessments before (Visit1) and after four weeks (Visit 2) of either IFN-alpha (n=17) or no treatment (n=14). Older patients treated with IFN-alpha exhibited a significantly increased glutamate from Visit 1 to Visit 2 as reflected by the glutamate/creatine ratio (Glu/Cr) in left basal ganglia compared to older controls and younger IFN-alpha-treated and untreated subjects. In addition, increased Glu/Cr in older but not younger IFN-alpha-treated and untreated patients was associated with increased tumor necrosis factor, reduced motivation as measured by the Multidimensional Fatigue Inventory and increased choice movement time on the Cambridge Neuropsychological Test Automated Battery. Taken together, these preliminary data support the notion that older age may interact with inflammation to exaggerate the effects of inflammatory stimuli on CNS glutamate and behavior. PMID:25500218

  19. Phase width reduction project summary

    SciTech Connect

    Clark, D.J.; Xie, Z.Q.; McMahan, M. A.

    1999-11-01

    The purpose of the phase width reduction project, 1993--96, was to reduce the phase width of the 88-Inch Cyclotron beam on target from 5--10 ns to 1--2 ns for certain experiments, such as Gammasphere, which use time-of-flight identification. Since reducing the phase width also reduces beam intensity, tuning should be done to also optimize the transmission. The Multi-turn Collimator slits in the cyclotron center region were used to collimate the early turns radially, thus reducing the phase width from about 5 ns to 1--2 ns FWHM for a Gammasphere beam. The effect of the slits on phase width was verified with a Fast Faraday Cup and with particle and gamma-ray detectors in the external beamline.

  20. Measles virus infection enhances IL-1 beta but reduces tumor necrosis factor-alpha expression in human monocytes.

    PubMed

    Leopardi, R; Vainionpää, R; Hurme, M; Siljander, P; Salmi, A A

    1992-10-01

    Monocytes may play a role in the immunologic abnormalities caused by measles. The effect of measles virus (MV) infection on peripheral blood monocyte functions is poorly known. We report that MV-infected PBM have an altered pattern of IL-1 beta and TNF-alpha production in response to stimulation with LPS and PMA in vitro. MV-infected peripheral blood monocytes produced higher amounts of IL-1 beta, whereas the production of TNF-alpha was reduced. The same effect was observed in the human monocytic cell line THP-1, which was used for RNA analysis. An increased steady-state level of IL-1 beta mRNA was observed in MV-infected cells, and the level of TNF-alpha mRNA was reduced. However, both IL-1 beta and TNF-alpha had about 50% increased transcription rate. Analysis of the mRNA stability after transcriptional block by actinomycin D showed that the TNF-alpha mRNA had a reduced half-life in MV-infected cells (about 30 vs 80 min in uninfected cells), whereas IL-1 beta mRNA stability was similar in uninfected and MV-infected cells. These results indicate that MV infection disturbs the immunoregulatory network by interfering with the monocyte functions. PMID:1527385

  1. alpha-MSH tripeptide analogs activate the melanocortin 1 receptor and reduce UV-induced DNA damage in human melanocytes.

    PubMed

    Abdel-Malek, Zalfa A; Ruwe, Andrew; Kavanagh-Starner, Renny; Kadekaro, Ana Luisa; Swope, Viki; Haskell-Luevano, Carrie; Koikov, Leonid; Knittel, James J

    2009-10-01

    One skin cancer prevention strategy that we are developing is based on synthesizing and testing melanocortin analogs that reduce and repair DNA damage resulting from exposure to solar ultraviolet (UV) radiation, in addition to stimulating pigmentation. Previously, we reported the effects of tetrapeptide analogs of alpha-melanocortin (alpha-MSH) that were more potent and stable than the physiological alpha-MSH, and mimicked its photoprotective effects against UV-induced DNA damage in human melanocytes. Here, we report on a panel of tripeptide analogs consisting of a modified alpha-MSH core His(6)-d-Phe(7)-Arg(8), which contained different N-capping groups, C-terminal modifications, or arginine mimics. The most potent tripeptides in activating cAMP formation and tyrosinase of human melanocytes were three analogs with C-terminal modifications. The most effective C-terminal tripeptide mimicked alpha-MSH in reducing hydrogen peroxide generation and enhancing nucleotide excision repair following UV irradiation. The effects of these three analogs required functional MC1R, as they were absent in human melanocytes that expressed non-functional receptor. These results demonstrate activation of the MC1R by tripeptide melanocortin analogs. Designing small analogs for topical delivery should prove practical and efficacious for skin cancer prevention. PMID:19558415

  2. Hypoxia reduces constitutive and TNF-{alpha}-induced expression of monocyte chemoattractant protein-1 in human proximal renal tubular cells

    SciTech Connect

    Li Xuan; Kimura, Hideki . E-mail: hkimura@fmsrsa.fukui-med.ac.jp; Hirota, Kiichi; Sugimoto, Hidehiro; Yoshida, Haruyoshi

    2005-10-07

    Chronic hypoxia has been reported to be associated with macrophage infiltration in progressive forms of kidney disease. Here, we investigated the regulatory effects of hypoxia on constitutive and TNF-{alpha}-stimulated expression of monocyte chemoattractant protein-1 (MCP-1) in cultured human proximal renal tubular cells (HPTECs). Hypoxia reduced constitutive MCP-1 expression at the mRNA and protein levels in a time-dependent fashion for up to 48 h. Hypoxia also inhibited MCP-1 up-regulation by TNF-{alpha}. Treatment with actinomycin D showed that hypoxic down-regulation of MCP-1 expression resulted mainly from a decrease in the transcription but not the mRNA stability. Immunoblot and immunofluorescence analyses revealed that treatment with hypoxia or an iron chelator, desferrioxamine, induced nuclear accumulation of hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) in HPTECs. Desferrioxamine mimicked hypoxia in the reduction of MCP-1 expression. However, overexpression of a dominant negative form of HIF-1{alpha} did not abolish the hypoxia-induced reduction of MCP-1 expression in HPTECs. These results suggest that hypoxia is an important negative regulator of monocyte chemotaxis to the renal inflamed interstitium, by reducing MCP-1 expression partly via hypoxia-activated signals other than the HIF-1 pathway.

  3. Brief Report: Reduced Temporal-Central EEG Alpha Coherence During Joint Attention Perception in Adolescents with Autism Spectrum Disorder.

    PubMed

    Jaime, Mark; McMahon, Camilla M; Davidson, Bridget C; Newell, Lisa C; Mundy, Peter C; Henderson, Heather A

    2016-04-01

    Although prior studies have demonstrated reduced resting state EEG coherence in adults with autism spectrum disorder (ASD), no studies have explored the nature of EEG coherence during joint attention. We examined the EEG coherence of the joint attention network in adolescents with and without ASD during congruent and incongruent joint attention perception and an eyes-open resting condition. Across conditions, adolescents with ASD showed reduced right hemisphere temporal-central alpha coherence compared to typically developing adolescents. Greater right temporal-central alpha coherence during joint attention was positively associated with social cognitive performance in typical development but not in ASD. These results suggest that, in addition to a resting state, EEG coherence during joint attention perception is reduced in ASD. PMID:26659813

  4. The natural xanthone alpha-mangostin reduces oxidative damage in rat brain tissue.

    PubMed

    Márquez-Valadez, Berenice; Lugo-Huitrón, Rafael; Valdivia-Cerda, Verónica; Miranda-Ramírez, Luis Rubén; Pérez-De La Cruz, Verónica; González-Cuahutencos, Octavio; Rivero-Cruz, Isabel; Mata, Rachel; Santamaría, Abel; Pedraza-Chaverrí, José

    2009-02-01

    The antiperoxidative properties of alpha-mangostin, a xanthone isolated from mangosteen fruit, were tested for the first time in nerve tissue exposed to different toxic insults. Two reliable biological preparations (rat brain homogenates and synaptosomal P2 fractions) were exposed to the toxic actions of a free radical generator (ferrous sulfate), an excitotoxic agent (quinolinate), and a mitochondrial toxin (3-nitropropionate). alpha-Mangostin decreased the lipoperoxidative action of FeSO(4) in both preparations in a concentration-dependent manner, and completely abolished the peroxidative effects of quinolinate, 3-nitropropionate and FeSO(4) + quinolinate at all concentrations tested. Interestingly, when tested alone in brain homogenates, alpha-mangostin significantly decreased the lipoperoxidation even below basal levels. alpha-Mangostin also prevented the decreased reductant capacity of mitochondria in synaptosomal fractions. Our results suggest that alpha-mangostin exerts a robust antiperoxidative effect in brain tissue preparations probably through its properties as a free radical scavenger. In light of these findings, this antioxidant should be tested in other neurotoxic models involving oxidative stress. PMID:19178790

  5. Alpha-1 antitrypsin reduces ovariectomy-induced bone loss in mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alpha-1antitrypsin (AAT) is a multifunctional protein with proteinase inhibitor and anti-inflammatory activities. Recent studies showed that AAT has therapeutic effect for diseases associated with inflammation, such as type 1 diabetes and arthritis. Proinflammatory cytokines are primary mediators of...

  6. Reduced alpha(2)-adrenergic sensitivity of subcutaneous abdominal adipocytes as a modulator of fasting and postprandial triglyceride levels in men.

    PubMed

    Imbeault, P; Couillard, C; Tremblay, A; Després, J P; Mauriège, P

    2000-09-01

    such as body weight, percent body fat, visceral and subcutaneous abdominal adipose tissue accumulation measured by CT, as well as subcutaneous abdominal fat cell alpha(2)-adrenoceptor sensitivity. Taken together, these results indicate that a reduced antilipolytic sensitivity of subcutaneous abdominal adipocytes to catecholamines may increase fasting TG levels, which in turn play a role in the etiology of an impaired postprandial TRL clearance in men. PMID:10974043

  7. Ceramides and cell signaling molecules in psoriatic epidermis: reduced levels of ceramides, PKC-alpha, and JNK.

    PubMed

    Lew, Bark-Lynn; Cho, Yunhi; Kim, Jungmin; Sim, Woo-Young; Kim, Nack-In

    2006-02-01

    Ceramides are the main lipids in the stratum corneum and are generated during cellular stress and apoptosis by de novo synthesis or by the action of sphingomyelinase. In addition, they are lipid second messengers produced by sphingolipid metabolism and trigger important cell responses, including protein kinase C-alpha (PKC-alpha) activation and the stimulation of signal transduction pathways with apoptosis and stress-activated protein kinases (SAPK), such as c-jun N-terminal kinase (JNK). Thus, ceramides have anti-proliferative and apoptotic effects. This study measured the changes in the levels of epidermal ceramides and ceramide-related apoptotic signaling molecules in psoriasis patients. Samples from lesional and non-lesional epidermis were obtained from psoriasis patients. Total ceramides were fractionated using thin-layer chromatography, and the levels of PKC-alpha and JNK expression were measured using Western blot analysis with specific antibodies. The ceramide level was reduced significantly, and this was associated with the downregulation of apoptotic signaling molecules, such as PKC-alpha and JNK, in the lesional epidermis of psoriasis patients. These results suggest that the decreased level of ceramides downregulates the apoptotic pathway, leading to epidermal proliferation in psoriasis. PMID:16479073

  8. Inhibition of TNF-alpha reduces myocardial injury and proinflammatory pathways following ischemia-reperfusion in the dog.

    PubMed

    Gu, Qiuping; Yang, Xiao Ping; Bonde, Pramod; DiPaula, Anthony; Fox-Talbot, Karen; Becker, Lewis C

    2006-12-01

    We examined whether tumor necrosis factor-alpha (TNF-alpha) promotes postischemic inflammation and myocardial injury via activation of nuclear factor kappa B (NFkappaB) in an in vivo canine model. Isoflurane-anesthetized dogs underwent closed-chest balloon occlusion of the anterior descending coronary artery for 90 minutes, followed by reperfusion for 3 hours. Dogs randomly received a soluble TNF inhibitor (etanercept, 0.5 mg/kg intravenously) or saline before occlusion. Collateral blood flow and risk region size (RISK) were measured with radioactive microspheres, infarct size (INF) was measured by triphenyltetrazolium chloride staining, inflammation was measured by tissue myeloperoxidase (MPO) activity, intercellular adhesion molecular-1 (ICAM-1) messenger ribonucleic acid (mRNA) was measured by Northern blotting, and ICAM-1 protein expression was measured by Western blotting. NFkappaB activation was measured in nuclear extracts by electrophoretic mobility shift assays. INF/RISK was significantly smaller in the etanercept group than in the saline control group after adjusting for collateral flow (P < 0.009 by analysis of covariance, mean reduction in INF/RISK = 40%, 0.32 +/- 0.09 versus 0.53 +/- 0.09). MPO activity, ICAM-1 mRNA and protein expression, and NFkappaB binding activity were all significantly reduced in the etanercept group. Administration of a soluble TNF-alpha inhibitor reduced NFkappaB activation, ICAM-1 upregulation, and myocardial injury following ischemia-reperfusion. TNF-alpha appears to play a significant role in vivo in the genesis of postischemic inflammation. PMID:17204912

  9. Relation between increased anxiety and reduced expression of alpha1 and alpha2 subunits of GABA(A) receptors in Wfs1-deficient mice.

    PubMed

    Raud, Sirli; Sütt, Silva; Luuk, Hendrik; Plaas, Mario; Innos, Jürgen; Kõks, Sulev; Vasar, Eero

    2009-08-28

    Mutations in the coding region of the WFS1 gene cause Wolfram syndrome, a rare multisystem neurodegenerative disorder of autosomal recessive inheritance. In clinical studies a relation between mutations in the Wfs1 gene and increased susceptibility for mood disorders has been established. According to our previous studies, mice lacking Wfs1 gene displayed increased anxiety in stressful environment. As the GABA-ergic system plays a significant role in the regulation of anxiety, we analyzed the expression of GABA-related genes in the forebrain structures of wild-type and Wfs1-deficient mice. Experimentally naïve Wfs1-deficient animals displayed a significant down-regulation of alpha1 (Gabra1) and alpha2 (Gabra2) subunits of GABA(A) receptors in the temporal lobe and frontal cortex. Exposure of wild-type mice to the elevated plus-maze decreased levels of Gabra1 and Gabra2 genes in the temporal lobe. A similar tendency was also established in the frontal cortex of wild-type animals exposed to behavioral test. In Wfs1-deficient mice the elevated plus-maze exposure did not induce further changes in the expression of Gabra1 and Gabra2 genes. By contrast, the expression of Gad1 and Gad2 genes, enzymes responsible for the synthesis of GABA, was not significantly affected by the exposure of mice to the elevated plus-maze or by the invalidation of Wfs1 gene. Altogether, the present study demonstrates that increased anxiety of Wfs1-deficient mice is probably linked to reduced expression of Gabra1 and Gabra2 genes in the frontal cortex and temporal lobe. PMID:19477223

  10. Novel fluorinated antiinflammatory steroid with reduced side effects: methyl 9 alpha-fluoroprednisolone-16-carboxylate.

    PubMed

    McLean, H M; Khalil, M A; Heiman, A S; Lee, H J

    1994-04-01

    In an effort to test the hypothesis that 9 alpha-fluorination of a steroidal antedrug would enhance receptor binding affinity and local antiinflammatory activity, without concomitantly increasing adverse systemic effects, a fluorinated analog, 10, of methyl 11 beta, 21-dihydroxy- 3,20-dioxo-1,4-pregnadiene-16 alpha-carboxylate (DP16CM, 1) was synthesized and evaluated. In the acute rat croton oil-induced ear edema bioassay, 10 was found to be twice as potent as 1. This increase in topical potency was consistent with enhanced binding affinity of 10, relative to 1. The IC50 values for displacement of [3H]dexamethasone from glucocorticoid receptors of rat hepatoma tissue culture cells were 0.16, 1.2, and 0.03 microM for 10, 1, and prednisolone, respectively. Following multiple topical ID50 applications of predniosolone, 1, and its new fluorinated analog, 10, in the rat subacute croton oil-induced ear edema bioassay, only prednisolone exhibited significant untoward effects, such as reduction in relative thymus and adrenal weights, plasma corticosterone levels, and normal body weight gain. Thus, while fluroination of 1 enhanced its topical potency, there was not a concomitant increase in untoward systemic effects. This lack of adverse systemic effects is ostensibly due to the presence of the metabolically labile 16-carboxylate ester moiety. PMID:7913964

  11. Characterization of a non-reducing terminal fragment from bovine articular cartilage keratan sulphates containing alpha(2-3)-linked sialic acid and alpha(1-3)-linked fucose. A sulphated variant of the VIM-2 epitope.

    PubMed Central

    Brown, G M; Huckerby, T N; Abram, B L; Nieduszynski, I A

    1996-01-01

    Alkaline-borohydride-reduced keratan sulphate chains were isolated from bovine articular cartilage (6-8-year-old animals) and digested with keratanase II, an endo- beta-N-acetylglucosaminidase. The resulting oligosaccharides were borohydride-reduced and fractionated on a strong anion-exchange column. 1H-NMR spectroscopic analysis of the products revealed one containing both alpha(2-3)-linked sialic acid and alpha(1-3)-linked fucose which was shown to have the structure (I) shown. This structure is a sulphated variant of the VIM-2 epitope (CD65), a putative ligand of E-selectin. No oligosaccharide containing the sialyl-Le(+) structure [NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc beta 1-] was identified in this study. [equation: see text] PMID:8870660

  12. Major vault protein forms complexes with hypoxia-inducible factor (HIF)-1alpha and reduces HIF-1alpha level in ACHN human renal adenocarcinoma cells.

    PubMed

    Iwashita, Ken-ichi; Ikeda, Ryuji; Takeda, Yasuo; Sumizawa, Tomoyuki; Furukawa, Tatsuhiko; Yamaguchi, Tatsuya; Akiyama, Shin-ichi; Yamada, Katsushi

    2010-04-01

    Vaults are evolutionarily highly conserved ribonucleoprotein (RNP) particles with a hollow barrel-like structure. Although roles in multidrug resistance and innate immunity have been suggested, the physiological function of vaults remains unclear. Major vault protein (MVP), the main component of the vault particle, has been reported to be induced by hypoxia. However, there are no reports about the effect of vaults on cellular responses to hypoxia. We thus examined whether vaults are implicated in cellular responses to hypoxia. In this study, we focused on hypoxia-inducible factor-1alpha (HIF-1alpha), which is a master regulator of hypoxic responses, and found that: (i) MVP knockdown by RNA interference increases HIF-1alpha protein levels induced by hypoxia and hypoxia mimetics; (ii) MVP knockdown does not affect HIF-1alpha mRNA levels, but decreases the ubiquitination and degradation of HIF-1alpha protein; and (iii) vaults form complexes with HIF-1alpha, PHD2, and pVHL. Taken together, these results suggest that vaults function as scaffolds in HIF-1alpha degradation pathway and promote the ubiquitination and degradation of HIF-1alpha. PMID:20175781

  13. A new monoclonal antibody DAG-6F4 against human alpha-dystroglycan reveals reduced core protein in some, but not all, dystroglycanopathy patients.

    PubMed

    Humphrey, Emma L; Lacey, Erica; Le, Lam T; Feng, Lucy; Sciandra, Francesca; Morris, Charlotte R; Hewitt, Jane E; Holt, Ian; Brancaccio, Andrea; Barresi, Rita; Sewry, Caroline A; Brown, Susan C; Morris, Glenn E

    2015-01-01

    We generated a novel monoclonal antibody, DAG-6F4, against alpha-dystroglycan which immunolabels the sarcolemma in human muscle biopsies. Its seven amino-acid epitope, PNQRPEL, was identified using phage-displayed peptides and is located immediately after the highly-glycosylated mucin domain of alpha-dystroglycan. On Western blots of recombinant alpha-dystroglycan, epitope accessibility was reduced, but not entirely prevented, by glycosylation. DAG-6F4 immunolabelling was markedly reduced in muscle biopsies from Duchenne muscular dystrophy patients consistent with disruption of the dystroglycan complex. In a range of dystroglycanopathy patients with reduced/altered glycosylation, staining by DAG-6F4 was often less reduced than staining by IIH6 (antibody against the glycan epitope added by LARGE and commonly used to identify glycosylated alpha-dystroglycan). Whereas IIH6 was reduced in all patients, DAG-6F4 was hardly changed in a LARGE patient, less reduced than IIH6 in limb-girdle muscular dystrophy type 2I, but as reduced as IIH6 in some congenital muscular dystrophy patients. Although absence of the LARGE-dependent laminin-binding site appears not to affect alpha-dystroglycan stability at the sarcolemma, the results suggest that further reduction in aDG glycosylation may reduce its stability. These studies suggest that DAG-6F4 may be a useful addition to the antibody repertoire for evaluating the dystroglycan complex in neuromuscular disorders. PMID:25387694

  14. Suppression of hypoxia-inducible factor-1alpha and its downstream genes reduces acute hyperglycemia-enhanced hemorrhagic transformation in a rat model of cerebral ischemia.

    PubMed

    Chen, Chunhua; Ostrowski, Robert P; Zhou, Changman; Tang, Jiping; Zhang, John H

    2010-07-01

    We evaluated a role of hypoxia-inducible factor-1alpha (HIF-1alpha) and its downstream genes in acute hyperglycemia-induced hemorrhagic transformation in a rat model of focal cerebral ischemia. Male Sprague-Dawley rats weighing 280-300 g (n = 105) were divided into sham, 90 min middle cerebral artery occlusion (MCAO), MCAO plus HIF-1alpha inhibitors, 2-methoxyestradiol (2ME2) or 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1), groups. Rats received an injection of 50% dextrose (6 ml/kg intraperitoneally) at 15 min before MCAO. HIF-1alpha inhibitors were administered at the onset of reperfusion. The animals were examined for neurological deficits and sacrificed at 6, 12, 24, and 72 hr following MCAO. The cerebral tissues were collected for histology, zymography, and Western blot analysis. The expression of HIF-1alpha was increased in ischemic brain tissues after MCAO and reduced by HIF-1alpha inhibitors. In addition, 2ME2 reduced the expression of vascular endothelial growth factor (VEGF) and the elevation of active matrix metalloproteinase-2 and -9 (MMP-2/MMP-9) in the ipsilateral hemisphere. Both 2ME2 and YC-1 reduced infarct volume and ameliorated neurological deficits. However, only 2ME2 attenuated hemorrhagic transformation in the ischemic territory. In conclusion, the inhibition of HIF-1alpha and its downstream genes attenuates hemorrhagic conversion of cerebral infarction and ameliorates neurological deficits after focal cerebral ischemia. PMID:20155812

  15. The nutraceutical potential of omega-3 alpha-linolenic acid in reducing the consequences of stroke.

    PubMed

    Blondeau, Nicolas

    2016-01-01

    Stroke is a worldwide major cause of mortality and morbidity. Preclinical studies have identified over 1000 molecules with brain-protective properties. More than 200 clinical trials have evaluated neuroprotective candidates for ischemic stroke yet, to date almost all failed, leading to a re-analysis of treatment strategies against stroke. An emerging view is to seek combinatory therapy, or discovering molecules able to stimulate multiple protective and regenerative mechanisms. A pertinent experimental approach to identify such candidates is the study of brain preconditioning, which refers to how the brain protects itself against ischemia and others stress-inducing stimuli. The recent discovery that nutrients like alpha-linolenic acid (ALA is an essential omega-3 polyunsaturated fatty acid required as part of our daily diet), may be an efficient brain preconditionner against stroke fosters the novel concept of brain preconditioning by nutraceuticals. This review stresses the underestimated role of nutrition in preventing and combating stroke. Although there is a consensus that increased consumption of salt, fatty foods and alcoholic beverages may promote pathologies like hypertension, obesity and alcoholism - all of which are well known risk factors of stroke - few risk factors are attributed to a deficiency in an essential nutrient in the diet. The ALA deficiency observed in the Western modern diets may itself constitute a risk factor. This review outlines how ALA supplementation by modification of the daily diet prevented mortality and cerebral damage in a rodent model of ischemic stroke. It also describes the pleiotropic ability of ALA to trigger responses that are multicellular, mechanistically diverse, resulting in neuronal protection, stimulation of neuroplasticity, and brain artery vasodilation. Overall, this review proposes a promising therapeutic opportunity by integrating a nutritional-based approach focusing on enriching the daily diet in ALA to prevent

  16. Propanil inhibits tumor necrosis factor-alpha production by reducing nuclear levels of the transcription factor nuclear factor-kappab in the macrophage cell line ic-21.

    PubMed

    Frost, L L; Neeley, Y X; Schafer, R; Gibson, L F; Barnett, J B

    2001-05-01

    Tumor necrosis factor-alpha (TNF-alpha) is an essential proinflammatory cytokine whose production is normally stimulated by bacterial cell wall components, such as lipopolysaccharide (LPS), during an infection. Macrophages stimulated with LPS in vitro produce several cytokines, including TNF-alpha. LPS-stimulated primary mouse macrophages produced less TNF-alpha protein and message after treatment with the herbicide propanil (Xie et al., Toxicol. Appl. Pharmacol. 145, 184-191, 1997). Nuclear factor-kappaB (NF-kappaB) tightly regulates TNF-alpha transcription. Therefore, as a step toward understanding the mechanism of the effect of propanil on TNF-alpha transcription, IC-21 cells were transfected with a TNF-alpha promoter-luciferase construct, and the effect of propanil on luciferase activity was measured. Cells transfected with promoter constructs containing a kappaB site showed decreased luciferase activity relative to controls after propanil treatment. These observations implicated NF-kappaB binding as an intracellular target of propanil. Further studies demonstrated a marked reduction in the nuclear levels of the stimulatory p65 subunit of NF-kappaB after propanil treatment, as measured by fluorescence confocal microscopy and Western blot analysis. The p50 subunit of NF-kappaB was not found to be reduced after propanil exposure by Western blot. Electrophoretic mobility gel shift assays showed decreased DNA binding of both p65/p50 heterodimers and p50/p50 homodimers to the kappaB3 site of the TNF-alpha promoter of propanil-treated cells. The marked reduction in nuclear p65/p50 NF-kappaB levels and diminished binding to the TNF-alpha promoter in propanil-treated cells are consistent with reduced TNF-alpha levels induced by LPS. PMID:11312646

  17. Targeting of Alpha-V Integrins Reduces Malignancy of Bladder Carcinoma

    PubMed Central

    van der Horst, Geertje; Bos, Lieke; van der Mark, Maaike; Cheung, Henry; Heckmann, Bertrand; Clément-Lacroix, Philippe; Lorenzon, Giocondo; Pelger, Rob C. M.; Bevers, Rob F. M.; van der Pluijm, Gabri

    2014-01-01

    Low survival rates of metastatic cancers emphasize the need for a drug that can prevent and/or treat metastatic cancer. αv integrins are involved in essential processes for tumor growth and metastasis and targeting of αv integrins has been shown to decrease angiogenesis, tumor growth and metastasis. In this study, the role of αv integrin and its potential as a drug target in bladder cancer was investigated. Treatment with an αv integrin antagonist as well as knockdown of αv integrin in the bladder carcinoma cell lines, resulted in reduced malignancy invitro, as illustrated by decreased proliferative, migratory and clonogenic capacity. The CDH1/CDH2 ratio increased, indicating a shift towards a more epithelial phenotype. This shift appeared to be associated with downregulation of EMT-inducing transcription factors including SNAI2. The expression levels of the self-renewal genes NANOG and BMI1 decreased as well as the number of cells with high Aldehyde Dehydrogenase activity. In addition, self-renewal ability decreased as measured with the urosphere assay. In line with these observations, knockdown or treatment of αv integrins resulted in decreased metastatic growth in preclinical invivo models as assessed by bioluminescence imaging. In conclusion, we show that αv integrins are involved in migration, EMT and maintenance of Aldehyde Dehydrogenase activity in bladder cancer cells. Targeting of αv integrins might be a promising approach for treatment and/or prevention of metastatic bladder cancer. PMID:25247809

  18. Increased Expression of Alpha-Synuclein Reduces Neurotransmitter Release by Inhibiting Synaptic Vesicle Reclustering After Endocytosis

    PubMed Central

    Nemani, Venu M.; Lu, Wei; Berge, Victoria; Nakamura, Ken; Onoa, Bibiana; Lee, Michael K.; Chaudhry, Farrukh A.; Nicoll, Roger A.; Edwards, Robert H.

    2011-01-01

    Summary The protein α-synuclein accumulates in the brain of patients with sporadic Parkinson’s disease (PD), and increased gene dosage causes a severe, dominantly inherited form of PD, but we know little about the effects of synuclein that precede degeneration. α-Synuclein localizes to the nerve terminal, but the knockout has little if any effect on synaptic transmission. In contrast, we now find that the modest over-expression of α-synuclein, in the range predicted for gene multiplication and in the absence of overt toxicity, markedly inhibits neurotransmitter release. The mechanism, elucidated by direct imaging of the synaptic vesicle cycle, involves a specific reduction in size of the synaptic vesicle recycling pool. Ultrastructural analysis demonstrates reduced synaptic vesicle density at the active zone, and imaging further reveals a defect in the reclustering of synaptic vesicles after endocytosis. Increased levels of α-synuclein thus produce a specific, physiological defect in synaptic vesicle recycling that precedes detectable neuropathology. PMID:20152114

  19. Tryptophan mutations at azi-etomidate photo-incorporation sites on alpha1 or beta2 subunits enhance GABAA receptor gating and reduce etomidate modulation.

    PubMed

    Stewart, Deirdre; Desai, Rooma; Cheng, Qi; Liu, Aiping; Forman, Stuart A

    2008-12-01

    The potent general anesthetic etomidate produces its effects by enhancing GABA(A) receptor activation. Its photolabel analog [(3)H]azi-etomidate labels residues within transmembrane domains on alpha and beta subunits: alphaMet236 and betaMet286. We hypothesized that these methionines contribute to etomidate sites formed at alpha-beta subunit interfaces and that increasing side-chain bulk and hydrophobicity at either locus would mimic etomidate binding and block etomidate effects. Channel activity was electrophysiologically quantified in alpha(1)beta(2)gamma(2L) receptors with alpha(1)M236W or beta(2)M286W mutations, in both the absence and the presence of etomidate. Measurements included spontaneous activation, GABA EC(50), etomidate agonist potentiation, etomidate direct activation, and rapid macrocurrent kinetics. Both alpha(1)M236W and beta(2)M286W mutations induced spontaneous channel opening, lowered GABA EC(50), increased maximal GABA efficacy, and slowed current deactivation, mimicking effects of etomidate on alpha(1)beta(2)gamma(2L) channels. These changes were larger with alpha(1)M236W than with beta(2)M286W. Etomidate (3.2 muM) reduced GABA EC(50) much less in alpha(1)M236Wbeta(2)gamma(2L) receptors (2-fold) than in wild type (23-fold). However, etomidate was more potent and efficacious in directly activating alpha(1)M236Wbeta(2)gamma(2L) compared with wild type. In alpha(1)beta(2)M286Wgamma(2L) receptors, etomidate induced neither agonist-potentiation nor direct channel activation. These results support the hypothesis that alpha(1)Met236 and beta(2)Met286 are within etomidate sites that allosterically link to channel gating. Although alpha(1)M236W produced the larger impact on channel gating, beta(2)M286W produced more profound changes in etomidate sensitivity, suggesting a dominant role in drug binding. Furthermore, quantitative mechanistic analysis demonstrated that wild-type and mutant results are consistent with the presence of only one class of

  20. Simultaneous determination of alpha-lipoic acid and its reduced form by high-performance liquid chromatography with fluorescence detection.

    PubMed

    Satoh, Soichiro; Toyo'oka, Toshimasa; Fukushima, Takeshi; Inagaki, Shinsuke

    2007-07-01

    The simultaneous determination of alpha-lipoic acid (LA) and DHLA (reduced form of LA) was carried out by HPLC with fluorescence detection. DHLA in the sample was first labeled with ABD-F at room temperature for 10 min and then the LA was labeled with SBD-F at 50 degrees C for 1 h after conversion to DHLA using the reducing agent, TCEP. The resulting fluorophores, ABD-DHLA and SBD-DHLA, were separated by reversed-phase chromatography and detected at 510 nm (excitation at 380 nm). Both fluorophors were completely separated without any interference of endogenous thiols and disulfides in the sample and sensitively detected by fluorimetry. The proposed method was applied to the assay of the LA supplement and the determination in human plasma after the oral administration of LA tablets. The concentration (%) of LA in the tablet was reasonable to the stated amount. Furthermore, the result of a time course study in the plasma after the administration of LA did not differ from a previous report. Thus, the present method seems to be applicable to the simultaneous determination of LA and DHLA in various biological specimens. PMID:17462965

  1. Passive Immunization Reduces Behavioral and Neuropathological Deficits in an Alpha-Synuclein Transgenic Model of Lewy Body Disease

    PubMed Central

    Masliah, Eliezer; Rockenstein, Edward; Mante, Michael; Crews, Leslie; Spencer, Brian; Adame, Anthony; Patrick, Christina; Trejo, Margarita; Ubhi, Kiren; Rohn, Troy T.; Mueller-Steiner, Sarah; Seubert, Peter; Barbour, Robin; McConlogue, Lisa; Buttini, Manuel; Games, Dora; Schenk, Dale

    2011-01-01

    Dementia with Lewy bodies (DLB) and Parkinson's Disease (PD) are common causes of motor and cognitive deficits and are associated with the abnormal accumulation of alpha-synuclein (α-syn). This study investigated whether passive immunization with a novel monoclonal α-syn antibody (9E4) against the C-terminus (CT) of α-syn was able to cross into the CNS and ameliorate the deficits associated with α-syn accumulation. In this study we demonstrate that 9E4 was effective at reducing behavioral deficits in the water maze, moreover, immunization with 9E4 reduced the accumulation of calpain-cleaved α-syn in axons and synapses and the associated neurodegenerative deficits. In vivo studies demonstrated that 9E4 traffics into the CNS, binds to cells that display α-syn accumulation and promotes α-syn clearance via the lysosomal pathway. These results suggest that passive immunization with monoclonal antibodies against the CT of α-syn may be of therapeutic relevance in patients with PD and DLB. PMID:21559417

  2. Osteoclast formation is strongly reduced both in vivo and in vitro in the absence of CD47/SIRP{alpha}-interaction

    SciTech Connect

    Lundberg, Pernilla . E-mail: pernilla.lundberg@odont.umu.se; Koskinen, Cecilia; Baldock, Paul A.; Loethgren, Hanna; Stenberg, Asa; Lerner, Ulf H.; Oldenborg, Per-Arne

    2007-01-12

    Physical interaction between the cell surface receptors CD47 and signal regulatory protein alpha (SIRP{alpha}) was reported to regulate cell migration, phagocytosis, cytokine production, and macrophage fusion. However, it is unclear if the CD47/SIRP{alpha}-interaction can also regulate macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor (NF)-{kappa}B ligand (RANKL)-stimulated formation of osteoclasts. Here, we show that functional blocking antibodies to either CD47 or SIRP{alpha} strongly reduced formation of multinucleated tartrate-resistant acid phosphatase (TRAP){sup +} osteoclasts in cultures of murine hematopoietic cells, stimulated in vitro by M-CSF and RANKL. In addition, the numbers of osteoclasts formed in M-CSF/RANKL-stimulated bone marrow macrophage cultures from CD47 {sup -/-} mice were strongly reduced, and bones of CD47 {sup -/-} mice exhibited significantly reduced osteoclast numbers, as compared with wild-type controls. We conclude that the CD47/SIRP{alpha} interaction is important for M-CSF/RANKL-stimulated osteoclast formation both in vivo and in vitro, and that absence of CD47 results in decreased numbers of osteoclasts in CD47 {sup -/-} mice.

  3. Exogenous IFN-alpha Administration Reduces Influenza A Virus Replication in the Lower Respiratory Tract of Rhesus Macaques

    PubMed Central

    Matzinger, Shannon R.; Carroll, Timothy D.; Fritts, Linda; McChesney, Michael B.; Miller, Christopher J.

    2011-01-01

    To determine the role of innate immune responses in controlling influenza A virus replication, rhesus macaques (RM) were administered pegylated IFN-alpha prior to virus challenge. Systemic and mucosal pegylated IFN-alpha administration induced expression of the interferon-stimulated genes (ISG) MxA and OAS in the airways. RM treated with IFN-alpha 24 hours prior to influenza virus challenge had significantly lower peak vRNA levels in the trachea compared to untreated animals. In addition to blunting viral replication, IFN-alpha treatment minimized the weight loss and spike in body temperature after influenza infection of RM. These results confirm the importance of IFN-alpha induced innate immune responses in the rapid control of influenza A virus replication in primates. PMID:22220209

  4. A 3D Radiative Transfer Simulation of Lyma-alpha Backscatter Intensity Reduced From Voyager’s Ultraviolet Spectrometer

    NASA Astrophysics Data System (ADS)

    Fayock, Brian; Zank, Gary; Heerikhuisen, Jacob

    2014-06-01

    Models of the heliosphere have evolved for the past few decades to fit observations made by a large number of spacecraft. Voyager missions have provided unique in-situ measurements that have proven to be essential for model testing. Lyman-alpha backscatter intensity has been reduced from measurements taken by the ultraviolet spectrometers on board both Voyager spacecraft. We have developed a 3D Monte Carlo radiative transfer code to simulate this backscatter intensity by generating millions of photons from the sun to scatter within a neutral hydrogen distribution resulting from a state-of-the-art 3D MHD-kinetic neutral heliospheric model, both of which have been developed within the Center for Space Physics and Aeronomic Research at the University of Alabama in Huntsville. While many have attempted to simulate the Voyager observations, we are the first to achieve agreement with our results. In this presentation, we will discuss the core mechanisms driving the radiative transfer code, the statistical quantities collected, and the interpretation of the results relative to the spacecraft data.

  5. Ethanol reduces GABAA alpha1 subunit receptor surface expression by a protein kinase Cgamma-dependent mechanism in cultured cerebral cortical neurons.

    PubMed

    Kumar, Sandeep; Suryanarayanan, Asha; Boyd, Kevin N; Comerford, Chris E; Lai, Marvin A; Ren, Qinglu; Morrow, A Leslie

    2010-05-01

    Prolonged ethanol exposure causes central nervous system hyperexcitability that involves a loss of GABAergic inhibition. We previously demonstrated that long-term ethanol exposure enhances the internalization of synaptic GABA(A) receptors composed of alpha1beta2/3gamma2 subunits. However, the mechanisms of ethanol-mediated internalization are unknown. This study explored the effect of ethanol on surface expression of GABA(A) alpha1 subunit-containing receptors in cultured cerebral cortical neurons and the role of protein kinase C (PKC) beta, gamma, and epsilon isoforms in their trafficking. Cultured neurons were prepared from rat pups on postnatal day 1 and maintained for 18 days. Cells were exposed to ethanol, and surface receptors were isolated by biotinylation and P2 fractionation, whereas functional analysis was conducted by whole-cell patch-clamp recording of GABA- and zolpidem-evoked responses. Ethanol exposure for 4 h decreased biotinylated surface expression of GABA(A) receptor alpha1 subunits and reduced zolpidem (100 nM) enhancement of GABA-evoked currents. The PKC activator phorbol-12,13-dibutyrate mimicked the effect of ethanol, and the selective PKC inhibitor calphostin C prevented ethanol-induced internalization of these receptors. Ethanol exposure for 4 h also increased the colocalization and coimmunoprecipitation of PKCgamma with alpha1 subunits, whereas PKCbeta/alpha1 association and PKCepsilon/alpha1 colocalization were not altered by ethanol exposure. Selective PKCgamma inhibition by transfection of selective PKCgamma small interfering RNAs blocked ethanol-induced internalization of GABA(A) receptor alpha1 subunits, whereas PKCbeta inhibition using pseudo-PKCbeta had no effect. These findings suggest that ethanol exposure selectively alters PKCgamma translocation to GABA(A) receptors and PKCgamma regulates GABA(A) alpha1 receptor trafficking after ethanol exposure. PMID:20159950

  6. GABA(A) receptor alpha1 subunit mutation A322D associated with autosomal dominant juvenile myoclonic epilepsy reduces the expression and alters the composition of wild type GABA(A) receptors.

    PubMed

    Ding, Li; Feng, Hua-Jun; Macdonald, Robert L; Botzolakis, Emanuel J; Hu, Ningning; Gallagher, Martin J

    2010-08-20

    A GABA(A) receptor (GABA(A)R) alpha1 subunit mutation, A322D (AD), causes an autosomal dominant form of juvenile myoclonic epilepsy (ADJME). Previous studies demonstrated that the mutation caused alpha1(AD) subunit misfolding and rapid degradation, reducing its total and surface expression substantially. Here, we determined the effects of the residual alpha1(AD) subunit expression on wild type GABA(A)R expression to determine whether the AD mutation conferred a dominant negative effect. We found that although the alpha1(AD) subunit did not substitute for wild type alpha1 subunits on the cell surface, it reduced the surface expression of alpha1beta2gamma2 and alpha3beta2gamma2 receptors by associating with the wild type subunits within the endoplasmic reticulum and preventing them from trafficking to the cell surface. The alpha1(AD) subunit reduced surface expression of alpha3beta2gamma2 receptors by a greater amount than alpha1beta2gamma2 receptors, thus altering cell surface GABA(A)R composition. When transfected into cultured cortical neurons, the alpha1(AD) subunit altered the time course of miniature inhibitory postsynaptic current kinetics and reduced miniature inhibitory postsynaptic current amplitudes. These findings demonstrated that, in addition to causing a heterozygous loss of function of alpha1(AD) subunits, this epilepsy mutation also elicited a modest dominant negative effect that likely shapes the epilepsy phenotype. PMID:20551311

  7. 1 alpha-hydroxyvitamin D3 plus 25-hydroxyvitamin D3 reduces parturient paresis in dairy cows fed high dietary calcium.

    PubMed

    Hodnett, D W; Jorgensen, N A; Deluca, H F

    1992-02-01

    The effectiveness of a combination of 1 alpha-hydroxyvitamin D3 and 25-hydroxyvitamin D3 for reducing incidence of parturient paresis in aged Holstein cows was tested. Intramuscular injection of .5 mg of 1 alpha-hydroxyvitamin D3 plus 4 mg of 25-hydroxyvitamin D3 increased plasma 1,25-dihydroxyvitamin D concentrations through parturition. Treatment with 1 alpha-hydroxyvitamin D3 plus 25-hydroxyvitamin D3 raised prepartum serum Ca approximately 2 mg/dl and prepartum serum P approximately 4 to 5 mg/dl higher than untreated controls. Both treated and control cows had approximately a 2-mg/dl decrease in serum Ca following parturition. The prepartum diet of alfalfa silage and hay was supplemented with a grain mixture supplying 100 g of Ca/d from ground limestone. Under these dietary conditions, incidence of parturient paresis was reduced from 33 to 8%. In a separate experiment, treatment with 1 alpha-hydroxyvitamin D3 plus 25-hydroxyvitamin D3 did not reduce incidence of parturient paresis when cows consumed mixed diets of different feed-stuff composition. Further experiments are required to determine specifically the factor or factors responsible for the difference in response to active vitamin D compound administration between the two experiments. Prepartum dietary Ca intake may be one such factor. PMID:1560144

  8. Resonances and resonance widths

    SciTech Connect

    Collins, T.

    1986-05-01

    Two-dimensional betatron resonances are much more important than their simple one-dimensional counterparts and exhibit a strong dependence on the betatron phase advance per cell. A practical definition of ''width'' is expanded upon in order to display these relations in tables. A primarily pedagogical introduction is given to explain the tables, and also to encourage a wider capability for deriving resonance behavior and wider use of ''designer'' resonances.

  9. Narrow Width Pentaquarks

    NASA Astrophysics Data System (ADS)

    Buccella, F.; Sorba, P.

    A general study of pentaquarks built with four quarks in a L=1 state and an antiquark in S-wave shows that several of such states are forbidden by a selection rule, which holds in the limit of flavor symmetry, to decay into a baryon and a meson final state. We identify the most promising /line{10} multiplet for the classification of the Θ+ and Ξ-- particles recently discovered with the prediction of a narrow width for both of them.

  10. Eugenol reduces acute pain in mice by modulating the glutamatergic and tumor necrosis factor alpha (TNF-α) pathways.

    PubMed

    Dal Bó, Wladmir; Luiz, Ana Paula; Martins, Daniel F; Mazzardo-Martins, Leidiane; Santos, Adair R S

    2013-10-01

    Eugenol is utilized together with zinc oxide in odontological clinical for the cementation of temporary prostheses and the temporary restoration of teeth and cavities. This work explored the antinociceptive effects of the eugenol in different models of acute pain in mice and investigated its possible modulation of the inhibitory (opioid) and excitatory (glutamatergic and pro-inflammatory cytokines) pathways of nociceptive signaling. The administration of eugenol (3-300 mg/kg, p.o., 60 min or i.p., 30 min) inhibited 82 ± 10% and 90 ± 6% of the acetic acid-induced nociception, with ID₅₀ values of 51.3 and 50.2 mg/kg, respectively. In the glutamate test, eugenol (0.3-100 mg/kg, i.p.) reduced the response behavior by 62 ± 5% with an ID₅₀ of 5.6 mg/kg. In addition, the antinociceptive effect of eugenol (10 mg/kg, i.p.) in the glutamate test was prevented by the i.p. treatment for mice with naloxone. The pretreatment of mice with eugenol (10 mg/kg, i.p.) was able to inhibit the nociception induced by the intrathecal (i.t.) injection of glutamate (37 ± 9%), kainic (acid kainite) (41 ± 12%), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) (55 ± 5%), and substance P (SP) (39 ± 8%). Furthermore, eugenol (10 mg/kg, i.p.) also inhibited biting induced by tumor necrosis factor alpha (TNF-α, 65 ± 8%). These results extend our current knowledge of eugenol and confirm that it promotes significant antinociception against different mouse models of acute pain. The mechanism of action appears to involve the modulation of the opioid system and glutamatergic receptors (i.e., kainate and AMPA), and the inhibition of TNF-α. Thus, eugenol could represent an important compound in the treatment for acute pain. PMID:22775297

  11. Reducing renal uptake of 90Y- and 177Lu-labeled alpha-melanocyte stimulating hormone peptide analogues

    SciTech Connect

    Miao, Yubin; Fisher, Darrell R.; Quinn, Thomas P.

    2006-06-15

    The purpose of this study was to improve the tumor-to-kidney uptake ratios of 90Y- and 177Lu-[1,2,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-Re-Cys,D-Phe,Arg]alpha-melanocyte stimulating hormone (DOTA-RE(Arg)CCMSH), through coupling a negatively charged glutamic acid (Glu) to the peptide sequence. A new peptide of DOTA-Re(Glu,Arg)CCMSH was designed, synthesized and labeled with 90Y and 177Lu. Pharmacokinetics of 90Y- and 177Lu-DOTA-RE(Glu,Arg)CCNSH were determined in B16/F1 murine melanoma-bearing C57 mice. Both exhibited significantly less renal uptake than 90Y- and 177Lu-DOTA-Re(Arg)CCMSH at 30 min and at 2, 3, and 24 h after dose administration. The renal uptake values of 90Y- and 177Lu-DOTA-Re(Glu,Arg)CCMSH were 28.16% and 28.81% of those of 90Y- and 177Lu-DOTA-RE(Arg)CCMSH, respectively, at 4 hr post-injection. We also showed higher tumor-to-kidney uptake ratios 2.28 and 1.69 times that of 90Y- and 177Lu-DOTA-Re(Arg)CCMSH, respectively, at 4 h post-injection. The90Y- and 177Lu-DOTA-Re(Glu,Arg)CCMSH activity accumulation was low in normal organs except for kidneys. Coupling a negatively charged amino acid (Glu) to the CCMSH peptide sequence dramatically reduced the renal uptake values and increased the tumor-to-kidney uptake ratios of 90Y- and 177Lu-DOTA-Re(Glu,Arg)CCMSH, facilitating their potential applications as radiopharmaceuticals for targeted radionuclide therapy of melanoma.

  12. Corticosteroid-binding globulin cleavage is paradoxically reduced in alpha-1 antitrypsin deficiency: Implications for cortisol homeostasis.

    PubMed

    Nenke, Marni A; Holmes, Mark; Rankin, Wayne; Lewis, John G; Torpy, David J

    2016-01-15

    High-affinity corticosteroid-binding globulin (haCBG) is cleaved by neutrophil elastase (NE) resulting in permanent transition to the low cortisol-binding affinity form (laCBG), thereby increasing cortisol availability at inflammatory sites. Alpha-1 antitrypsin (AAT) is the major inhibitor of NE. AAT deficiency (AATD) predisposes patients to early-onset emphysema due to increased proteolytic destruction from the inherent proteinase-antiproteinase imbalance. We hypothesized that AATD may result in increased CBG cleavage in vivo. We collected demographic data and blood samples from 10 patients with AATD and 28 healthy controls measuring total CBG and haCBG levels by parallel in-house ELISAs, as well as AAT, total and free cortisol levels. haCBG was higher (median [range]); 329 [210-551] vs. 250 [175-365] nmol/L; P<0.005, and laCBG lower; 174 [68-229] vs. 220 [119-348] nmol/L; P=0.016 in the AATD group, compared with controls. The ratio of haCBG:total CBG was also higher in AATD; 72 [53-83] vs. 54 [41-72] %; P=0.0001). There was a negative correlation between haCBG:total CBG and AAT levels (P<0.05, R=-0.64). Paradoxically, proteolytic cleavage of CBG was reduced in AATD, despite the recognized increase in NE activity. This implies that NE activity is not the mechanism for systemic CBG cleavage in basal, low inflammatory conditions. Relatively low levels of laCBG may have implications for cortisol action in AATD. PMID:26522656

  13. Low voltage alpha EEG phenotype is associated with reduced amplitudes of alpha event-related oscillations, increased cortical phase synchrony, and a low level of response to alcohol.

    PubMed

    Ehlers, Cindy L; Wills, Derek N; Phillips, Evelyn; Havstad, James

    2015-10-01

    Low voltage EEG (LVEEG) is a heritable phenotype that differs depending on ancestral heritage, yet its impact on brain networks and cognition remain relatively unexplored. In this study we assessed energy and task related phase locking of event-related oscillation (EROs), behavioral responses, measures of IQ and personality, and expected responses to alcohol in a large sample of individuals with LVEEG compared to those with higher voltage variants. Participants (n=762) were recruited from a Native American community and completed a diagnostic interview, the Quick Test, the Subjective High Assessment Scale Expectation Version (SHAS-E) and the Maudsley Personality Inventory. Clinical and spectral analyzed EEGs were collected for determination of the presence of a LVEEG variant. EROs were generated using a facial expression recognition task. Participants with LVEEG (n=451) were significantly more likely to be older, married and have higher degrees of Native American heritage but did not differ in gender, income or education. Individuals with LVEEG were also found to have decreased energy in their alpha EROs, increased phase locking between stimulus trials, and increased phase-locking between cortical brain areas. No significant differences in the cognitive tests, personality variables or alcohol dependence or anxiety diagnoses were found, however, individuals with LVEEG did report a larger number of drinks ever consumed in a 24-h period and a less intense expected response to alcohol. These data suggest that alpha power in the resting EEG is highly associated with energy and cortical connectivity measures generated by event-related stimuli, as well as potentially increased risk for alcohol use. PMID:26151497

  14. In vivo transfer of soluble TNF-alpha receptor 1 gene improves cardiac function and reduces infarct size after myocardial infarction in rats.

    PubMed

    Sugano, Masahiro; Tsuchida, Keiko; Hata, Tomoji; Makino, Naoki

    2004-05-01

    Increased circulating and cardiac TNF-alpha levels during myocardial ischemia have been found in both experimental animals and patients with ischemic heart disease and advanced heart failure. Soluble TNF-alpha receptor 1 (sTNFR1) is an antagonist to TNF-alpha. In the present study, we examined whether sTNFR1 improves cardiac function in rats after myocardial infarction. Male Wistar rats were subjected to left coronary artery (LCA) ligation. Immediately after the ligation, a total of 200 microg of either the sTNFR1 or LacZ plasmid was injected into three different sites in the left ventricular wall. From 1 to 21 days after LCA ligation, TNF-alpha bioactivity in the heart was higher in rats receiving LacZ plasmid than in sham-operated rats, whereas sTNFR1 plasmid significantly suppressed the increase. The LV diastolic dimension was significantly lower, and the fractional shortening was significantly higher in rats treated with the sTNFR1 plasmid than in those treated with the LacZ plasmid. At 21 days after LCA ligation, the LV end-diastolic pressure was also significantly lower in the rats treated with the sTNFR1 plasmid. In addition, the sTNFR1 expression plasmid had significantly reduced the infarct size. In conclusion, TNF-alpha bioactivity in the heart increased during the early stage of infarction and remained elevated. This elevation seemed partially responsible for the impairment of LV function and the increased infarct size. Suppression of TNF-alpha bioactivity from the early stage of infarction with the sTNFR1 plasmid improved cardiac function and reduced infarct size. PMID:15117889

  15. Platelets of the Wistar Furth rat have reduced levels of alpha-granule proteins. An animal model resembling gray platelet syndrome.

    PubMed Central

    Jackson, C W; Hutson, N K; Steward, S A; Saito, N; Cramer, E M

    1991-01-01

    Rats of the Wistar Furth (WF) strain have hereditary macrothrombocytopenia (large mean platelet volume [MPV] with increased platelet size heterogeneity and reduced platelet count). Ultrastructural studies suggest that this anomaly results from erratic subdivision of megakaryocyte cytoplasm into platelets. In this study, we have examined protein profiles of platelets of WF rats for biochemical abnormalities associated with this anomaly. Marked decreases in protein bands with an Mr of 185, 57, 53, 16, 13, and 8 kd were observed in one-dimensional reduced SDS-PAGE gels in WF platelets compared with platelets of Wistar, Long Evans, and Sprague-Dawley rats. These proteins were released into the supernatant when washed platelets were treated with thrombin suggesting that they were alpha-granule proteins. These abnormalities were not present in offspring of crosses between Wistar Furth and Wistar rats; however, they were present in platelets of offspring with large MPV derived from backcrosses of (WF X Wistar) F1 males to WF females, but not in backcross offspring with normal platelet size. Immunoblotting confirmed decreased levels of thrombospondin, fibrinogen, and platelet factor 4 in WF platelets. Electron microscopic examination revealed that platelet alpha granules were usually smaller in Wistar Furth than in Wistar rats. In addition, immunogold electron microscopy demonstrated that the surface connected canalicular system of the large Wistar Furth platelets, contained dense material composed of alpha-granule proteins, not present in Wistar platelets. From these results, we conclude that the Wistar Furth rat platelet phenotype of large mean platelet volume and decreased levels of alpha-granule proteins represents an animal model resembling gray platelet syndrome. The autosomal recessive pattern of inheritance of the large MPV phenotype and platelet alpha-granule protein deficiencies suggests that a component common to both formation of platelet alpha granules, and

  16. Tc-99m-labeled RGD-conjugated alpha-melanocyte stimulating hormone hybrid peptides with reduced renal uptake

    PubMed Central

    Yang, Jianquan; Hu, Chien-An

    2015-01-01

    The purpose of this study was to examine whether the replacement of the positively-charged Lys or Arg linker with a neutral linker could reduce the renal uptake of Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide. The RGD motif {cyclic(Arg-Gly-Asp-dTyr-Asp)} was coupled to [Cys3,4,10, d-Phe7, Arg11]α-MSH3–13 {(Arg11)CCMSH} through the neutral βAla or Ahx {aminohexanoic acid} linker (replacing the Lys or Arg linker) to generate novel RGD-βAla-(Arg11)CCMSH and RGD-Ahx-(Arg11)CCMSH hybrid peptides. The receptor binding affinity and cytotoxicity of RGD-βAla-(Arg11)CCMSH and RGD-Ahx-(Arg11)CCMSH were determined in B16/F1 melanoma cells. The melanoma targeting and imaging properties of 99mTc-RGD-βAla-(Arg11)CCMSH and 99mTc-RGD-Ahx-(Arg11)CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The replacement of the Lys or Arg linker with the βAla or Ahx linker retained nanomolar receptor binding affinities and remarkable cytotoxicity of RGD-βAla-(Arg11)CCMSH and RGD-Ahx-(Arg11)CCMSH. The receptor binding affinities of RGD-βAla-(Arg11)CCMSH and RGD-Ahx-(Arg11)CCMSH were 0.8 and 1.3 nM. Three-hour incubation with 0.1 µM of RGD-βAla-(Arg11)CCMSH and RGD-Ahx-(Arg11)CCMSH decreased the survival percentages of B16/F1 cells by 71 and 67% as compared to the untreated control cells five days post the treatment. The replacement of the Arg linker with the βAla or Ahx linker reduced the non-specific renal uptake of 99mTc-RGD-βAla-(Arg11)CCMSH and 99mTc-RGD-Ahx-(Arg11)CCMSH by 62% and 61% at 2 h post-injection. 99mTc-RGD-βAla-(Arg11)CCMSH displayed higher melanoma uptake than 99mTc-RGD-Ahx-(Arg11)CCMSH at 0.5, 2, 4 and 24 h post-injection. Enhanced tumor to kidney uptake ratio of 99mTc-RGD-βAla-(Arg11)CCMSH warranted the further evaluation of 188Re-labeled RGD-βAla-(Arg11)CCMSH as a novel MC1 receptor-targeting therapeutic peptide for melanoma treatment in the future. PMID:25557051

  17. Diatomic predissociation line widths

    NASA Technical Reports Server (NTRS)

    Child, M. S.

    1973-01-01

    Predissociation by rotation and curve crossing in diatomic molecules is discussed. The pattern of predissociation line widths is seen as providing a highly sensitive yardstick for the determination of unknown potential curves. In addition, the computation of such a pattern for given potential curves is considered a matter of routine, unless the predissociation happens to occur from an adiabatic potential curve. Analytic formulas are used to provide physical insight into the details of the predissociation pattern, to the extent that a direct inversion procedure is developed for determination of the repulsive potential curves for Type 1 predissociations.

  18. Alpha-globin loci in homozygous beta-thalassemia intermedia.

    PubMed

    Triadou, P; Lapoumeroulie, C; Girot, R; Labie, D

    1983-01-01

    Homozygous beta-thalassemia intermediate (TI) differs from thalassemia major (TM) in being less severe clinically. Associated alpha-thalassemia could account for the TI phenotype by reducing the alpha/non-alpha chain imbalance. We have analyzed the alpha loci of 9 TI and 11 TM patients by restriction endonuclease mapping. All the TM and 7 of the TI patients have the normal complement of four alpha-globin genes (alpha alpha/alpha alpha). One TI patient has three alpha-globin genes (alpha alpha/-alpha), and another TI patient has five alpha genes (alpha alpha/alpha alpha alpha). PMID:6305827

  19. Simulated Microgravity Reduces TNF-Alpha Activity, Suppresses Glucose Uptake and Enhances Arginine Flux in Pancreatic Islets of Langerhans

    NASA Technical Reports Server (NTRS)

    Tobin, Brian W.; Leeper-Woodford, Sandra K.; Hashemi, Brian B.; Smith, Scott M.; Sams, Clarence F.; Paloski, W. H. (Technical Monitor)

    2000-01-01

    The present studies were designed to determine effects of microgravity upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF - alpha) activity and indices of insulin and fuel homeostasis of pancreatic islets of Langerhans. Islets (1726+/-117,150 u IEU) from Wistar Furth rats were treated as: 1) HARV (High Aspect Ratio Vessel cell culture) , 2) HARV plus LPS 3) static culture, 4) static culture plus LPS TNF-alpha (L929 cytotoxicity assay) was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (p<0.05). A decrease in insulin concentration was demonstrated in the LPS stimulated HARV culture (p<0.05). We observed a greater glucose concentration and increased disappearance of arginine in islets cultured in HARVs. While nitrogenous compound analysis indicated a ubiquitous reliance upon glutamine in all experimental groups, arginine was converted to ornithine at a two-fold greater rate in the islets cultured in the HARV microgravity paradigm (p<0.05). These studies demonstrate alterations in LPS induced TNF-alpha production of pancreatic islets of Langerhans, favoring a lesser TNF activity in the HARV paradigm. These alterations in fuel homeostasis may be promulgated by gravity averaged cell culture methods or by three dimensional cell assembly.

  20. Width of nonlinear resonance

    SciTech Connect

    Ohnuma, S.

    1984-03-01

    Two approximations are made, one essential and the other not so essential but convenient to keep the analytical treatment manageable: (1) Only one nonlinear resonance is considered at a time so that the treatment is best suited when the tune is close to one resonance only. To improve this approximation, one must go to the next order which involves a canonical transformation of dynamical variables. Analytical treatment of more than one resonance is not possible for general cases. (2) In the formalism using the action-angle variables, the Hamiltonian can have terms which are independent of the angle variables. These terms are called phase-independent terms or shear terms. The tune is then a function of the oscillation amplitudes. In the lowest-order treatment, the (4N)-pole components but not the (4N + 2)-pole components contribute to this dependence. In deriving the resonance width analytically, one ignores these terms in the Hamiltonian for the sake of simplicity. If these are retained, one needs at least three extra parameters and the analytical treatment becomes rather unwieldy.

  1. Phlorotannin-rich Ecklonia cava reduces the production of beta-amyloid by modulating alpha- and gamma-secretase expression and activity.

    PubMed

    Kang, Il-Jun; Jang, Bong Geom; In, Sua; Choi, Boyoung; Kim, Misook; Kim, Min-Ju

    2013-01-01

    Beta-amyloid (Aβ) is a major pathogenic peptide in Alzheimer's disease (AD) and is generated by the processing of amyloid precursor protein (APP). We have previously reported that the brown algae Ecklonia cava, which has anti-oxidant and anti-inflammatory functions, decreased Aβ production and further aggregation in HEK293 cells expressing the APP Swedish mutation. Here, we show the reduction mechanism of Aβ production using the butanol extract of Ecklonia cava through the examination of expression and activity of alpha-, beta-, and gamma-secretase. Treatment with the extract resulted in the activation of alpha-secretase with a contrasting decrease in its mRNA and protein expression. This activation was consistent with the translocation of the extract into the plasma membrane of the secretase. Gamma-secretase activity was lowered by E. cava, and this effect may be due to the decreased expression of PSEN1 mRNA and protein. In addition, the basal nuclear location of PSEN1, which may affect chromosome missegregation in neurodegenerative disease, was reduced by the extract, despite the significance of this finding remains unclear. Taken together, these results led us to conclude that E. cava regulated the expression and activity of gamma-secretase and alpha-secretase, leading to a reduction in Aβ production by the stable cells. Our data indicate that E. cava is a novel natural-product candidate for AD treatment, although further in vivo studies are needed. PMID:23041113

  2. A diet supplemented with husks of Plantago ovata reduces the development of endothelial dysfunction, hypertension, and obesity by affecting adiponectin and TNF-alpha in obese Zucker rats.

    PubMed

    Galisteo, Milagros; Sánchez, Manuel; Vera, Rocío; González, Mercedes; Anguera, Anna; Duarte, Juan; Zarzuelo, Antonio

    2005-10-01

    The aim of the present study was to analyze whether consumption of a fiber-supplemented diet containing 3.5% Plantago ovata husks prevented many of the abnormalities clustered in the metabolic syndrome, including obesity, dyslipidemia, hypertension and endothelial dysfunction. For this purpose, obese Zucker rats, a model of type 2 diabetes, and their lean littermates were studied. Rats consumed a standard control diet or that diet supplemented with 3.5% P. ovata husks for 25 wk. Body weights were measured weekly. Systolic blood pressure (SBP) was measured monthly. At the end of the treatment, plasma concentrations of triglycerides, total cholesterol, FFAs, glucose, insulin, adiponectin, and tumor necrosis factor alpha (TNF-alpha) were determined, and studies on vascular function were performed using aortic rings. Rats fed the P. ovata husk-supplemented diet had a significantly reduced body weight gain compared with those fed the standard diet. Decreased endothelium-dependent relaxation in response to acetylcholine (ACh) by aortic rings from obese Zucker rats was improved in those fed the fiber-supplemented diet. The greater SBP, higher plasma concentrations of triglycerides, total cholesterol, FFA, glucose, insulin, and TNF-alpha, and the hypoadinectinemia that occurred in obese Zucker rats that consumed the control diet were significantly improved in those fed the fiber-supplemented diet. We conclude that intake of a P. ovata husk-supplemented diet prevents endothelial dysfunction, hypertension, and obesity development, and ameliorates dyslipidemia and abnormal plasma concentrations of adiponectin and TNF-alpha in obese Zucker rats. PMID:16177203

  3. The Width of a Proof

    ERIC Educational Resources Information Center

    Hanna, Gila

    2014-01-01

    This paper's aim is to discuss the concept of width of a proof put forward by Timothy Gowers. It explains what this concept means and attempts to show how it relates to other concepts discussed in the existing literature on proof and proving. It also explores how the concept of width of a proof might be used productively in the mathematics…

  4. A non-reducing terminal fragment from tracheal cartilage keratan sulphate chains contains alpha (2-3)-linked N-acetylneuraminic acid.

    PubMed Central

    Dickenson, J M; Huckerby, T N; Nieduszynski, I A

    1991-01-01

    Keratan sulphate chains were isolated from bovine tracheal ring cartilage (15-18-month-old animals) after papain digestion of the tissue followed by ethanol fractionation, chondroitinase ABC digestion and alkaline borohydride reduction. The keratan sulphate chains were further purified by anion-exchange chromatography on a Pharmacia Mono-Q column in order to remove any contaminating chondroitin sulphate and O-linked oligosaccharides. The chains were then treated with keratanase and the digest was subjected to alkaline borohydride reduction, producing oligosaccharides with galactitol at their reducing ends. The reduced digest was chromatographed on a Nucleosil 5 SB anion-exchange column and individual oligosaccharides were isolated. One of these, oligosaccharide (I), was shown by 500 MHz 1H-n.m.r. spectroscopy to have the following structure: NeuAc alpha 2-3Gal beta 1-4GlcNAc(6SO4) beta 1-3Gal-ol (I) The structure of this oligosaccharide shows that keratan sulphate chains from bovine tracheal ring cartilage may be terminated with N-acetylneuraminic acid linked alpha (2-3) to an unsulphated galactose. Keratan sulphate chains were also isolated from bovine femoral head cartilage (15-18-month-old animals) using an identical protocol, but with keratanase which was subsequently shown to have sialidase activity. This yielded oligosaccharide (II), the unsialyated version of (I): Gal beta 1-4GlcNAc(6SO4) beta 1-3Gal-ol (II). PMID:1910336

  5. DO QUASAR BROAD-LINE VELOCITY WIDTHS ADD ANY INFORMATION TO VIRIAL BLACK HOLE MASS ESTIMATES?

    SciTech Connect

    Croom, Scott M.

    2011-08-01

    We examine how much information measured broad-line widths add to virial black hole (BH) mass estimates for flux-limited samples of quasars. We do this by comparing the BH mass estimates to those derived by randomly reassigning the quasar broad-line widths to different objects and re-calculating the BH mass. For 9000 BH masses derived from the H{beta} line we find that the distributions of original and randomized BH masses in the M{sub BH}-redshift plane and the M{sub BH}-luminosity plane are formally identical. A two-dimensional Kolmogorov-Smirnov test does not find a difference at >90% confidence. For the Mg II line (32,000 quasars) we do find very significant differences between the randomized and original BH masses, but the amplitude of the difference is still small. The difference for the C IV line (14,000 quasars) is 2{sigma}-3{sigma} and again the amplitude of the difference is small. Subdividing the data into redshift and luminosity bins we find that the median absolute difference in BH mass between the original and randomized data is 0.025, 0.01, and 0.04 dex for H{beta}, Mg II, and C IV, respectively. The maximum absolute difference is always {<=}0.1 dex. We investigate whether our results are sensitive to corrections to Mg II virial masses, such as those suggested by Onken and Kollmeier. These corrections do not influence our results, other than to reduce the significance of the difference between original and randomized BH masses to only 1{sigma}-2{sigma} for Mg II. Moreover, we demonstrate that the correlation between mass residuals and Eddington ratio discussed by Onken and Kollmeier is more directly attributable to the slope of the relation between H{beta} and Mg II line width. The implication is that the measured quasar broad-line velocity widths provide little extra information, after allowing for the mean velocity width. In this case virial estimates are equivalent to M{sub BH}{proportional_to}L{sup {alpha}}, with L/L{sub Edd

  6. The {beta}-delayed {alpha}-spectrum of {sup 16}N and the astrophysical aspects of the {sup 12}C({alpha},{gamma}){sup 16}O reaction

    SciTech Connect

    Azuma, R.E.; Buchmann, L.; Barker, F.C.

    1995-08-01

    Radiative alpha-capture by {sup 12}C is a key process occurring during the helium-burning phase in red giant stars, and its rate remains one of the most significant uncertainties in the nucleosynthetic calculations for massive stars. This is largely due to the lack of precise experimental information concerning the values of the reduced {alpha}-particle widths of the J{sup {pi}} = 1{sup {minus}} and 2{sup +} subthreshold states in {sup 16}O to which the higher-energy radiative capture data are only weakly sensitive. Of these two states, the reduced {alpha}-width of the E{sub x} = 7.12 MeV J{sup {pi}} = 1{sup {minus}} level has been predicted to have a considerable effect on the structure of the hitherto unmeasured low-energy region of the {beta}-delayed {alpha}-particle spectrum of {sup 16}N. Experiments using the TRIUMF isotope separator TISOL have been performed to measure this {alpha}-spectrum down to an energy of E{sub {alpha}} = 600 keV, utilizing a coincidence technique which also accounts completely for the detector response function. The {alpha}-spectrum, containing 10{sup 6} counts, has been incorporated into both R- and K-matrix analyses along with the previously measured {sup 12}C({alpha},{gamma}){sup 16}O cross section and the {sup 12}C + {alpha} elastic phase shifts to yield a much improved value for S{sub E1}(300) keV. In light of this new determination of S{sub E1}(300), the available radiative capture data and elastic scattering phase shifts are re-analyzed, along with {beta}-delayed {alpha}-spectrum of {sup 16}N in an attempt also to place improved limits on the S{sub E1}(300) contribution to the {sup 12}C({alpha},{gamma}){sup 16}O cross section.

  7. Mice expressing the A53T mutant form of human alpha-synuclein exhibit hyperactivity and reduced anxiety-like behavior.

    PubMed

    Graham, Dianca R; Sidhu, Anita

    2010-06-01

    Genetic mutations associated with alpha-synuclein (alpha-Syn) are implicated in the pathogenesis of Parkinson's disease (PD). PD is primarily a movement disorder, but patients are known to experience anxiety and other mood disorders. In this study, we examined the effect of the hA53T mutation during development by analyzing the protein expression of norepinephrine (NET), serotonin (SERT), and dopamine (DAT) transporters in addition to assessing locomotor and anxiety-like behavior. We observed significant decreases in DAT expression at 8 months in transgenic animals compared with normal and younger mice. We used the elevated plus maze, open-field test, and rotarod apparatus to evaluate wild-type and hA53T hemizygous mice at 2, 8, and 12 months of age. Our results showed that 12-month-old transgenic mice spend more time in the open arms and display a greater number of open entries of the elevated plus maze compared with wild-type controls and younger mice. Open-field test results showed that 12-month-old mice travel a greater distance overall and travel more in the inner zone than either wild-type or younger mice. Rotarod testing showed that 8- and 12-month-old transgenic mice perform better than either wild-type controls or younger mice. Overall, 8-12-month-old transgenic mice showed a trend toward reduced anxiety-like behavior and increased hyperactivity. These results indicate a possible role of the A53T alpha-Syn mutation in anxiety-like and hyperactive behaviors in a PD mouse model, suggesting that these behaviors might be comorbid with this disease. PMID:20077428

  8. Brief Report: Reduced Temporal-Central EEG Alpha Coherence during Joint Attention Perception in Adolescents with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Jaime, Mark; McMahon, Camilla M.; Davidson, Bridget C.; Newell, Lisa C.; Mundy, Peter C.; Henderson, Heather A.

    2016-01-01

    Although prior studies have demonstrated reduced resting state EEG coherence in adults with autism spectrum disorder (ASD), no studies have explored the nature of EEG coherence during joint attention. We examined the EEG coherence of the joint attention network in adolescents with and without ASD during congruent and incongruent joint attention…

  9. Alpha-lipoic acid supplementation reduces mTORC1 signaling in skeletal muscle from high fat fed, obese Zucker rats.

    PubMed

    Li, Zhuyun; Dungan, Cory M; Carrier, Bradley; Rideout, Todd C; Williamson, David L

    2014-12-01

    The mammalian target of rapamycin (mTOR) signaling pathway is hyperactive in liver, adipose and skeletal muscle tissues of obese rodents. Alpha-lipoic acid (αLA) has been well accepted as a weight-loss treatment, though there are limited studies on its effect on mTOR signaling in high-fat fed, obese rodents. Therefore, the goal of this study was to determine mTOR signaling and oxidative protein alterations in skeletal muscle of high-fat fed, obese rats after αLA supplementation. Phosphorylation of the mTOR substrate, eukaryotic initiation factor (eIF) 4E-binding protein 1 (4E-BP1) and eIF4B were significantly reduced (p < 0.05) in muscle from αLA supplemented rats. Activation of AMP-activated protein kinase (AMPK), an mTOR inhibitory kinase, was higher (p < 0.05) in the αLA group. Protein expression of markers of oxidative metabolism, acetyl CoA carboxylase (ACC), cytochrome c oxidase IV (COX IV), peroxisome proliferator-activated receptor (PPAR), and PPAR gamma coactivator 1-alpha (PGC-1α) were significantly higher (p < 0.05) after αLA supplementation compared to non-supplemented group. Our findings show that αLA supplementation limits the negative ramifications of consuming a high fat diet on skeletal muscle markers of oxidative metabolism and mTORC1 signaling. PMID:25366515

  10. Reducing C-terminal-truncated alpha-synuclein by immunotherapy attenuates neurodegeneration and propagation in Parkinson's disease-like models.

    PubMed

    Games, Dora; Valera, Elvira; Spencer, Brian; Rockenstein, Edward; Mante, Michael; Adame, Anthony; Patrick, Christina; Ubhi, Kiren; Nuber, Silke; Sacayon, Patricia; Zago, Wagner; Seubert, Peter; Barbour, Robin; Schenk, Dale; Masliah, Eliezer

    2014-07-01

    Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are common neurodegenerative disorders of the aging population, characterized by progressive and abnormal accumulation of α-synuclein (α-syn). Recent studies have shown that C-terminus (CT) truncation and propagation of α-syn play a role in the pathogenesis of PD/DLB. Therefore, we explored the effect of passive immunization against the CT of α-syn in the mThy1-α-syn transgenic (tg) mouse model, which resembles the striato-nigral and motor deficits of PD. Mice were immunized with the new monoclonal antibodies 1H7, 5C1, or 5D12, all directed against the CT of α-syn. CT α-syn antibodies attenuated synaptic and axonal pathology, reduced the accumulation of CT-truncated α-syn (CT-α-syn) in axons, rescued the loss of tyrosine hydroxylase fibers in striatum, and improved motor and memory deficits. Among them, 1H7 and 5C1 were most effective at decreasing levels of CT-α-syn and higher-molecular-weight aggregates. Furthermore, in vitro studies showed that preincubation of recombinant α-syn with 1H7 and 5C1 prevented CT cleavage of α-syn. In a cell-based system, CT antibodies reduced cell-to-cell propagation of full-length α-syn, but not of the CT-α-syn that lacked the 118-126 aa recognition site needed for antibody binding. Furthermore, the results obtained after lentiviral expression of α-syn suggest that antibodies might be blocking the extracellular truncation of α-syn by calpain-1. Together, these results demonstrate that antibodies against the CT of α-syn reduce levels of CT-truncated fragments of the protein and its propagation, thus ameliorating PD-like pathology and improving behavioral and motor functions in a mouse model of this disease. PMID:25009275

  11. Reducing C-Terminal-Truncated Alpha-Synuclein by Immunotherapy Attenuates Neurodegeneration and Propagation in Parkinson's Disease-Like Models

    PubMed Central

    Games, Dora; Valera, Elvira; Spencer, Brian; Rockenstein, Edward; Mante, Michael; Adame, Anthony; Patrick, Christina; Ubhi, Kiren; Nuber, Silke; Sacayon, Patricia; Zago, Wagner; Seubert, Peter; Barbour, Robin; Schenk, Dale

    2014-01-01

    Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are common neurodegenerative disorders of the aging population, characterized by progressive and abnormal accumulation of α-synuclein (α-syn). Recent studies have shown that C-terminus (CT) truncation and propagation of α-syn play a role in the pathogenesis of PD/DLB. Therefore, we explored the effect of passive immunization against the CT of α-syn in the mThy1-α-syn transgenic (tg) mouse model, which resembles the striato-nigral and motor deficits of PD. Mice were immunized with the new monoclonal antibodies 1H7, 5C1, or 5D12, all directed against the CT of α-syn. CT α-syn antibodies attenuated synaptic and axonal pathology, reduced the accumulation of CT-truncated α-syn (CT-α-syn) in axons, rescued the loss of tyrosine hydroxylase fibers in striatum, and improved motor and memory deficits. Among them, 1H7 and 5C1 were most effective at decreasing levels of CT-α-syn and higher-molecular-weight aggregates. Furthermore, in vitro studies showed that preincubation of recombinant α-syn with 1H7 and 5C1 prevented CT cleavage of α-syn. In a cell-based system, CT antibodies reduced cell-to-cell propagation of full-length α-syn, but not of the CT-α-syn that lacked the 118–126 aa recognition site needed for antibody binding. Furthermore, the results obtained after lentiviral expression of α-syn suggest that antibodies might be blocking the extracellular truncation of α-syn by calpain-1. Together, these results demonstrate that antibodies against the CT of α-syn reduce levels of CT-truncated fragments of the protein and its propagation, thus ameliorating PD-like pathology and improving behavioral and motor functions in a mouse model of this disease. PMID:25009275

  12. Alpha-tubulin enhanced renal tubular cell proliferation and tissue repair but reduced cell death and cell-crystal adhesion.

    PubMed

    Manissorn, Juthatip; Khamchun, Supaporn; Vinaiphat, Arada; Thongboonkerd, Visith

    2016-01-01

    Adhesion of calcium oxalate (CaOx) crystals on renal tubular epithelial cells is a critical event for kidney stone disease that triggers many cascades of cellular response. Our previous expression proteomics study identified several altered proteins in MDCK renal tubular cells induced by CaOx crystals. However, functional significance of those changes had not been investigated. The present study thus aimed to define functional roles of such proteome data. Global protein network analysis using STRING software revealed α-tubulin, which was decreased, as one of central nodes of protein-protein interactions. Overexpression of α-tubulin (pcDNA6.2-TUBA1A) was then performed and its efficacy was confirmed. pcDNA6.2-TUBA1A could maintain levels of α-tubulin and its direct interacting partner, vimentin, after crystal exposure. Also, pcDNA6.2-TUBA1A successfully reduced cell death to almost the basal level and increased cell proliferation after crystal exposure. Additionally, tissue repair capacity was improved in pcDNA6.2-TUBA1A cells. Moreover, cell-crystal adhesion was reduced by pcDNA6.2-TUBA1A. Finally, levels of potential crystal receptors (HSP90, HSP70, and α-enolase) on apical membrane were dramatically reduced to basal levels by pcDNA6.2-TUBA1A. These findings implicate that α-tubulin has protective roles in kidney stone disease by preventing cell death and cell-crystal adhesion, but on the other hand, enhancing cell proliferation and tissue repair function. PMID:27363348

  13. Alpha-tubulin enhanced renal tubular cell proliferation and tissue repair but reduced cell death and cell-crystal adhesion

    PubMed Central

    Manissorn, Juthatip; Khamchun, Supaporn; Vinaiphat, Arada; Thongboonkerd, Visith

    2016-01-01

    Adhesion of calcium oxalate (CaOx) crystals on renal tubular epithelial cells is a critical event for kidney stone disease that triggers many cascades of cellular response. Our previous expression proteomics study identified several altered proteins in MDCK renal tubular cells induced by CaOx crystals. However, functional significance of those changes had not been investigated. The present study thus aimed to define functional roles of such proteome data. Global protein network analysis using STRING software revealed α-tubulin, which was decreased, as one of central nodes of protein-protein interactions. Overexpression of α-tubulin (pcDNA6.2-TUBA1A) was then performed and its efficacy was confirmed. pcDNA6.2-TUBA1A could maintain levels of α-tubulin and its direct interacting partner, vimentin, after crystal exposure. Also, pcDNA6.2-TUBA1A successfully reduced cell death to almost the basal level and increased cell proliferation after crystal exposure. Additionally, tissue repair capacity was improved in pcDNA6.2-TUBA1A cells. Moreover, cell-crystal adhesion was reduced by pcDNA6.2-TUBA1A. Finally, levels of potential crystal receptors (HSP90, HSP70, and α-enolase) on apical membrane were dramatically reduced to basal levels by pcDNA6.2-TUBA1A. These findings implicate that α-tubulin has protective roles in kidney stone disease by preventing cell death and cell-crystal adhesion, but on the other hand, enhancing cell proliferation and tissue repair function. PMID:27363348

  14. Bounding the Higgs boson width through interferometry.

    PubMed

    Dixon, Lance J; Li, Ye

    2013-09-13

    We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg→γγ. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum. PMID:24074073

  15. Modeling Solar Lyman Alpha Irradiance

    NASA Technical Reports Server (NTRS)

    Pap, J.; Hudson, H. S.; Rottman, G. J.; Willson, R. C.; Donnelly, R. F.; London, J.

    1990-01-01

    Solar Lyman alpha irradiance is estimated from various solar indices using linear regression analyses. Models developed with multiple linear regression analysis, including daily values and 81-day running means of solar indices, predict reasonably well both the short- and long-term variations observed in Lyman alpha. It is shown that the full disk equivalent width of the He line at 1083 nm offers the best proxy for Lyman alpha, and that the total irradiance corrected for sunspot effect also has a high correlation with Lyman alpha.

  16. Isohumulones, bitter acids derived from hops, activate both peroxisome proliferator-activated receptor alpha and gamma and reduce insulin resistance.

    PubMed

    Yajima, Hiroaki; Ikeshima, Emiko; Shiraki, Maho; Kanaya, Tomoka; Fujiwara, Daisuke; Odai, Hideharu; Tsuboyama-Kasaoka, Nobuyo; Ezaki, Osamu; Oikawa, Shinichi; Kondo, Keiji

    2004-08-01

    The peroxisome proliferator-activated receptors (PPARs) are dietary lipid sensors that regulate fatty acid and carbohydrate metabolism. The hypolipidemic effects of fibrate drugs and the therapeutic benefits of the thiazolidinedione drugs are due to their activation of PPARalpha and -gamma, respectively. In this study, isohumulones, the bitter compounds derived from hops that are present in beer, were found to activate PPARalpha and -gamma in transient co-transfection studies. Among the three major isohumulone homologs, isohumulone and isocohumulone were found to activate PPARalpha and -gamma. Diabetic KK-Ay mice that were treated with isohumulones (isohumulone and isocohumulone) showed reduced plasma glucose, triglyceride, and free fatty acid levels (65.3, 62.6, and 73.1%, respectively, for isohumulone); similar reductions were found following treatment with the thiazolidinedione drug, pioglitazone. Isohumulone treatment did not result in significant body weight gain, although pioglitazone treatment did increase body weight (10.6% increase versus control group). C57BL/6N mice fed a high fat diet that were treated with isohumulones showed improved glucose tolerance and reduced insulin resistance. Furthermore, these animals showed increased liver fatty acid oxidation and a decrease in size and an increase in apoptosis of their hypertrophic adipocytes. A double-blind, placebo-controlled pilot study for studying the effect of isohumulones on diabetes suggested that isohumulones significantly decreased blood glucose and hemoglobin A1c levels after 8 weeks (by 10.1 and 6.4%, respectively, versus week 0). These results suggest that isohumulones can improve insulin sensitivity in high fat diet-fed mice with insulin resistance and in patients with type 2 diabetes. PMID:15178687

  17. /sup 12/C(/sup 6/Li,d)/sup 16/O. -->. cap alpha. +/sup 12/C reaction mechanism by means of angular correlation measurements

    SciTech Connect

    Cunsolo, A.; Foti, A.; Imme, G.; Pappalardo, G.; Raciti, G.; Saunier, N.

    1980-06-01

    The particle-particle angular correlation method is applied to the reaction /sup 12/C(/sup 6/Li,d)/sup 16/O ..-->.. ..cap alpha..+/sup 12/C. Deuterons were detected at theta/sup lab//sub d/=10/sup 0/. Information on the reaction mechanism is obtained by analyzing the shape and the angular shift of the experimental data. A dominant direct transfer mechanism is found for the primary reaction. The ratios GAMMA..cap alpha../sub 0//GAMMA and the ..cap alpha..-reduced widths ..gamma cap alpha../sub 0/ are deduced.

  18. Activation of Alpha 7 Cholinergic Nicotinic Receptors Reduce Blood–Brain Barrier Permeability following Experimental Traumatic Brain Injury

    PubMed Central

    Zhao, Jing; Kobori, Nobuhide; Redell, John B.; Hylin, Michael J.; Hood, Kimberly N.; Moore, Anthony N.

    2016-01-01

    Traumatic brain injury (TBI) is a major human health concern that has the greatest impact on young men and women. The breakdown of the blood–brain barrier (BBB) is an important pathological consequence of TBI that initiates secondary processes, including infiltration of inflammatory cells, which can exacerbate brain inflammation and contribute to poor outcome. While the role of inflammation within the injured brain has been examined in some detail, the contribution of peripheral/systemic inflammation to TBI pathophysiology is largely unknown. Recent studies have implicated vagus nerve regulation of splenic cholinergic nicotinic acetylcholine receptor α7 (nAChRa7) signaling in the regulation of systemic inflammation. However, it is not known whether this mechanism plays a role in TBI-triggered inflammation and BBB breakdown. Following TBI, we observed that plasma TNF-α and IL-1β levels, as well as BBB permeability, were significantly increased in nAChRa7 null mice (Chrna7−/−) relative to wild-type mice. The administration of exogenous IL-1β and TNF-α to brain-injured animals worsened Evans Blue dye extravasation, suggesting that systemic inflammation contributes to TBI-triggered BBB permeability. Systemic administration of the nAChRa7 agonist PNU-282987 or the positive allosteric modulator PNU-120596 significantly attenuated TBI-triggered BBB compromise. Supporting a role for splenic nAChRa7 receptors, we demonstrate that splenic injection of the nicotinic receptor blocker α-bungarotoxin increased BBB permeability in brain-injured rats, while PNU-282987 injection decreased such permeability. These effects were not seen when α-bungarotoxin or PNU-282987 were administered to splenectomized, brain-injured rats. Together, these findings support the short-term use of nAChRa7-activating agents as a strategy to reduce TBI-triggered BBB permeability. SIGNIFICANCE STATEMENT Breakdown of the blood–brain barrier (BBB) in response to traumatic brain injury (TBI

  19. The Lyman alpha coronagraph

    NASA Technical Reports Server (NTRS)

    Kohl, J. L.; Reeves, E. M.; Kirkham, B.

    1977-01-01

    The rocket-borne Lyman alpha coronagraph (RLAC) is to be used in the absence of a natural solar eclipse to determine coronal temperatures from measurements of the line width of Lyman-alpha and to determine neutral hydrogen densities of coronal material from the absolute intensity. The coronagraph consists of a 75-cm Fastie-Ebert scanning spectrometer with an AMR 641 photoelectric detection system, an off-axis parabolic primary mirror, and an occulting system. A special optical arrangement achieves rejection of radiation from the solar disk.

  20. Hypoxia-inducible factor 1 mediates hypoxia-induced cardiomyocyte lipid accumulation by reducing the DNA binding activity of peroxisome proliferator-activated receptor {alpha}/retinoid X receptor

    SciTech Connect

    Belanger, Adam J.; Luo Zhengyu; Vincent, Karen A.; Akita, Geoffrey Y.; Cheng, Seng H.; Gregory, Richard J.; Jiang Canwen

    2007-12-21

    In response to cellular hypoxia, cardiomyocytes adapt to consume less oxygen by shifting ATP production from mitochondrial fatty acid {beta}-oxidation to glycolysis. The transcriptional activation of glucose transporters and glycolytic enzymes by hypoxia is mediated by hypoxia-inducible factor 1 (HIF-1). In this study, we examined whether HIF-1 was involved in the suppression of mitochondrial fatty acid {beta}-oxidation in hypoxic cardiomyocytes. We showed that either hypoxia or adenovirus-mediated expression of a constitutively stable hybrid form (HIF-1{alpha}/VP16) suppressed mitochondrial fatty acid metabolism, as indicated by an accumulation of intracellular neutral lipid. Both treatments also reduced the mRNA levels of muscle carnitine palmitoyltransferase I which catalyzes the rate-limiting step in the mitochondrial import of fatty acids for {beta}-oxidation. Furthermore, adenovirus-mediated expression of HIF-1{alpha}/VP16 in cardiomyocytes under normoxic conditions also mimicked the reduction in the DNA binding activity of peroxisome proliferator-activated receptor {alpha} (PPAR{alpha})/retinoid X receptor (RXR), in the presence or absence of a PPAR{alpha} ligand. These results suggest that HIF-1 may be involved in hypoxia-induced suppression of fatty acid metabolism in cardiomyocytes by reducing the DNA binding activity of PPAR{alpha}/RXR.

  1. Exposure of the eggs to 17alpha-methyl testosterone reduced hatching success and growth and elicited teratogenic effects in postembryonic life stages of crayfish.

    PubMed

    Vogt, Günter

    2007-12-30

    Testosterone is regularly found in the tissues of decapod crustaceans. Although this vertebrate-type sex hormone is not the principal factor of sex differentiation in crustaceans, it was shown to be capable of acting on the reproductive organs of shrimps and crabs. In the present study I have exposed developing eggs and stage 5 juveniles of the parthenogenetic all female marbled crayfish to 17alpha-methyl testosterone in order to test whether in freshwater crayfish sex can be changed from female to male by this androgen. MT did not elicit sex change, neither when administered during embryonic development nor during juvenile stage 5, the main period of proliferation of the oocytes. However, exposure to 100 microg/L MT from 64% to 84% embryonic development resulted in prolonged embryonic development, reduced hatching success, reduced growth of the juveniles, and severe malformations of the appendages in the juveniles. The marbled crayfish is recommended to be considered for toxicity tests due to its easy culture in the laboratory and its genotypical uniformity. PMID:17983674

  2. Overexpression of the calpain-specific inhibitor calpastatin reduces human alpha-Synuclein processing, aggregation and synaptic impairment in [A30P]αSyn transgenic mice

    PubMed Central

    Diepenbroek, Meike; Casadei, Nicolas; Esmer, Hakan; Saido, Takaomi C.; Takano, Jiro; Kahle, Philipp J.; Nixon, Ralph A; Rao, Mala V.; Melki, Ronald; Pieri, Laura; Helling, Stefan; Marcus, Katrin; Krueger, Rejko; Masliah, Eliezer; Riess, Olaf; Nuber, Silke

    2014-01-01

    Lewy bodies, a pathological hallmark of Parkinson's disease (PD), contain aggregated alpha-synuclein (αSyn), which is found in several modified forms and can be discovered phosphorylated, ubiquitinated and truncated. Aggregation-prone truncated species of αSyn caused by aberrant cleavage of this fibrillogenic protein are hypothesized to participate in its sequestration into inclusions subsequently leading to synaptic dysfunction and neuronal death. Here, we investigated the role of calpain cleavage of αSyn in vivo by generating two opposing mouse models. We crossed into human [A30P]αSyn transgenic (i) mice deficient for calpastatin, a calpain-specific inhibitor, thus enhancing calpain activity (SynCAST(−)) and (ii) mice overexpressing human calpastatin leading to reduced calpain activity (SynCAST(+)). As anticipated, a reduced calpain activity led to a decreased number of αSyn-positive aggregates, whereas loss of calpastatin led to increased truncation of αSyn in SynCAST(−). Furthermore, overexpression of calpastatin decreased astrogliosis and the calpain-dependent degradation of synaptic proteins, potentially ameliorating the observed neuropathology in [A30P]αSyn and SynCAST(+) mice. Overall, our data further support a crucial role of calpains, particularly of calpain 1, in the pathogenesis of PD and in disease-associated aggregation of αSyn, indicating a therapeutic potential of calpain inhibition in PD. PMID:24619358

  3. Overexpression of the calpain-specific inhibitor calpastatin reduces human alpha-Synuclein processing, aggregation and synaptic impairment in [A30P]αSyn transgenic mice.

    PubMed

    Diepenbroek, Meike; Casadei, Nicolas; Esmer, Hakan; Saido, Takaomi C; Takano, Jiro; Kahle, Philipp J; Nixon, Ralph A; Rao, Mala V; Melki, Ronald; Pieri, Laura; Helling, Stefan; Marcus, Katrin; Krueger, Rejko; Masliah, Eliezer; Riess, Olaf; Nuber, Silke

    2014-08-01

    Lewy bodies, a pathological hallmark of Parkinson's disease (PD), contain aggregated alpha-synuclein (αSyn), which is found in several modified forms and can be discovered phosphorylated, ubiquitinated and truncated. Aggregation-prone truncated species of αSyn caused by aberrant cleavage of this fibrillogenic protein are hypothesized to participate in its sequestration into inclusions subsequently leading to synaptic dysfunction and neuronal death. Here, we investigated the role of calpain cleavage of αSyn in vivo by generating two opposing mouse models. We crossed into human [A30P]αSyn transgenic (i) mice deficient for calpastatin, a calpain-specific inhibitor, thus enhancing calpain activity (SynCAST(-)) and (ii) mice overexpressing human calpastatin leading to reduced calpain activity (SynCAST(+)). As anticipated, a reduced calpain activity led to a decreased number of αSyn-positive aggregates, whereas loss of calpastatin led to increased truncation of αSyn in SynCAST(-). Furthermore, overexpression of calpastatin decreased astrogliosis and the calpain-dependent degradation of synaptic proteins, potentially ameliorating the observed neuropathology in [A30P]αSyn and SynCAST(+) mice. Overall, our data further support a crucial role of calpains, particularly of calpain 1, in the pathogenesis of PD and in disease-associated aggregation of αSyn, indicating a therapeutic potential of calpain inhibition in PD. PMID:24619358

  4. Ly(alpha) emission and absorption features in the spectra of galaxies

    NASA Technical Reports Server (NTRS)

    Chen, W. L.; Neufeld, David A.

    1994-01-01

    The combined effects of interstellar dust absorption and of scattering by hydrogen atoms may give rise to a Ly(alpha) spectral feature of negative equivalent width, as has been observed in several star-forming galaxies. By considering the transfer of Ly(alpha) line radiation and of neighboring stellar continuum radiation within a dusty galaxy, we find that dust absorption has three effects: (1) it reduces the apparent ultraviolet continuum luminosity at all wavelengths; (2) it preferentially decreases the apparent Ly(alpha) line luminosity from H II regions; and (3) it creates an 'attenuation feature' in the continuum spectrum -- centered at the Ly(alpha) rest frequency -- which occurs because the attenuation of the stellar continuum radiation increases as the Ly(alpha) rest frequency is approached, due to the effects of scattering by hydrogen atoms. For plausible values of the galactic dust content and of the disk thickness, these effects can lead to a negative net Ly(alpha) equivalent width, even for galaxies in which the unattenuated spectrum would show a strong Ly(alpha) emission line.

  5. Ab initio alpha-alpha scattering

    NASA Astrophysics Data System (ADS)

    Elhatisari, Serdar; Lee, Dean; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A.; Luu, Thomas; Meißner, Ulf-G.

    2015-12-01

    Processes such as the scattering of alpha particles (4He), the triple-alpha reaction, and alpha capture play a major role in stellar nucleosynthesis. In particular, alpha capture on carbon determines the ratio of carbon to oxygen during helium burning, and affects subsequent carbon, neon, oxygen, and silicon burning stages. It also substantially affects models of thermonuclear type Ia supernovae, owing to carbon detonation in accreting carbon-oxygen white-dwarf stars. In these reactions, the accurate calculation of the elastic scattering of alpha particles and alpha-like nuclei—nuclei with even and equal numbers of protons and neutrons—is important for understanding background and resonant scattering contributions. First-principles calculations of processes involving alpha particles and alpha-like nuclei have so far been impractical, owing to the exponential growth of the number of computational operations with the number of particles. Here we describe an ab initio calculation of alpha-alpha scattering that uses lattice Monte Carlo simulations. We use lattice effective field theory to describe the low-energy interactions of protons and neutrons, and apply a technique called the ‘adiabatic projection method’ to reduce the eight-body system to a two-cluster system. We take advantage of the computational efficiency and the more favourable scaling with system size of auxiliary-field Monte Carlo simulations to compute an ab initio effective Hamiltonian for the two clusters. We find promising agreement between lattice results and experimental phase shifts for s-wave and d-wave scattering. The approximately quadratic scaling of computational operations with particle number suggests that it should be possible to compute alpha scattering and capture on carbon and oxygen in the near future. The methods described here can be applied to ultracold atomic few-body systems as well as to hadronic systems using lattice quantum chromodynamics to describe the interactions of

  6. Ab initio alpha-alpha scattering.

    PubMed

    Elhatisari, Serdar; Lee, Dean; Rupak, Gautam; Epelbaum, Evgeny; Krebs, Hermann; Lähde, Timo A; Luu, Thomas; Meißner, Ulf-G

    2015-12-01

    Processes such as the scattering of alpha particles ((4)He), the triple-alpha reaction, and alpha capture play a major role in stellar nucleosynthesis. In particular, alpha capture on carbon determines the ratio of carbon to oxygen during helium burning, and affects subsequent carbon, neon, oxygen, and silicon burning stages. It also substantially affects models of thermonuclear type Ia supernovae, owing to carbon detonation in accreting carbon-oxygen white-dwarf stars. In these reactions, the accurate calculation of the elastic scattering of alpha particles and alpha-like nuclei--nuclei with even and equal numbers of protons and neutrons--is important for understanding background and resonant scattering contributions. First-principles calculations of processes involving alpha particles and alpha-like nuclei have so far been impractical, owing to the exponential growth of the number of computational operations with the number of particles. Here we describe an ab initio calculation of alpha-alpha scattering that uses lattice Monte Carlo simulations. We use lattice effective field theory to describe the low-energy interactions of protons and neutrons, and apply a technique called the 'adiabatic projection method' to reduce the eight-body system to a two-cluster system. We take advantage of the computational efficiency and the more favourable scaling with system size of auxiliary-field Monte Carlo simulations to compute an ab initio effective Hamiltonian for the two clusters. We find promising agreement between lattice results and experimental phase shifts for s-wave and d-wave scattering. The approximately quadratic scaling of computational operations with particle number suggests that it should be possible to compute alpha scattering and capture on carbon and oxygen in the near future. The methods described here can be applied to ultracold atomic few-body systems as well as to hadronic systems using lattice quantum chromodynamics to describe the interactions of

  7. Inhibition of p53 by pifithrin-alpha reduces myocyte apoptosis and leukocyte transmigration in aged rat hearts following 24 hours of reperfusion.

    PubMed

    Liu, Peitan; Xu, Baohuan; Cavalieri, Thomas A; Hock, Carl E

    2008-11-01

    Ischemic heart disease is a common age-related disease. Apoptotic cell death and inflammation are the major contributors to I/R injury. The mechanisms that trigger myocyte apoptosis and inflammation during myocardial I/R (MI/R) remain to be elucidated. Published data from our laboratory demonstrated that pretreatment of MI/R rats with pifithrin-alpha (PFT), a specific p53 inhibitor, reduced myocyte apoptosis and improved cardiac function compared with MI/R rats pretreated with saline at 4 h of reperfusion. In the present study, we investigated the effects of PFT on the occurrence of myocyte apoptosis and leukocyte transmigration in the later period of reperfusion. Aged (20-month-old) male F344 rats were subjected to 30 min of myocardial ischemia via ligature of the LCA, followed by 24 h of reperfusion. Pifithrin-alpha (2.2 mg/kg, intraperitoneally) or saline was administered to rats before ischemia. The results indicate that pretreatment of MI/R rats with PFT significantly decreased the percentage of infarct area to ischemic area (33 +/- 8 vs. 54 +/- 9, P < 0.05) and improved cardiac output (79 +/- 11 vs. 38 +/- 9 mL/min per 100 g body weight, P < 0.05) when compared with rats pretreated with saline at 24 h of reperfusion. The protective effects of PFT may involve the p53/Bax-mediated apoptosis because treatment of MI/R rats with PFT attenuated the ratio of Bax to Bcl2 (0.97 +/- 0.1 vs. 2.1 +/- 0.2, P < 0.05) and reduced myocyte apoptosis. Interestingly, inhibition of p53 transcriptional function by PFT alleviated leukocyte infiltration into the ischemic area of the heart (339 +/- 37 vs. 498 +/- 75 cells/10 high-power fields, P < 0.05). These data suggest that inhibition of p53 transcriptional function by PFT attenuates myocyte apoptosis and alleviates leukocyte transmigration at 24 h of reperfusion. The mechanisms by which p53 modulates leukocyte transmigration require further investigation. PMID:18317410

  8. Combined Intraperitoneal and Intrathecal Etanercept Reduce Increased Brain Tumor Necrosis Factor-Alpha and Asymmetric Dimethylarginine Levels and Rescues Spatial Deficits in Young Rats after Bile Duct Ligation

    PubMed Central

    Sheen, Jiunn-Ming; Chen, Yu-Chieh; Hsu, Mei-Hsin; Tain, You-Lin; Yu, Hong-Ren; Huang, Li-Tung

    2016-01-01

    Background: Rats subjected to bile duct ligation (BDL) exhibit increased systemic oxidative stress and brain dysfunction characteristic of hepatic encephalopathy (HE), including fatigue, neurotransmitter alterations, cognitive and motor impairment, and brain inflammation. The levels of tumor necrosis factor-alpha (TNF-α) and asymmetric dimethylarginine (ADMA) are both increased in plasma and brain in encephalopathy induced by chronic liver failure. This study first determined the temporal profiles of TNF-α and ADMA in the plasma, brain cortex, and hippocampus in young BDL rats. Next, we examined whether etanercept was beneficial in preventing brain damage. Methods: Young rats underwent sham ligation or BDL at day 17 ± 1 for 4 weeks. Treatment group rats were administered etanercept (10 mg/kg) intraperitoneally (IP) three times per week with or without etanercept (100 μg) intrathecally (IT) three times in total. Results: We found increased plasma TNF-α, soluble tumor necrosis factor receptor 1 (sTNFR1), soluble tumor necrosis factor receptor 2 (sTNFR2), and ADMA levels, increased cortical TNF-α mRNA and protein and ADMA, and hippocampal TNF-α mRNA and protein, and spatial defects in young BDL rats. The increase in cortex TNF-α mRNA and ADMA were reduced by IP etanercept or combined IP and IT etanercept. Dually IP/IT etanercept administration reduced the increased cortical and hippocampal TNF-α mRNA and protein level as well as spatial deficits. Conclusions: We conclude that combined intraperitoneal and intrathecal etanercept reduce increased brain TNF-α and ADMA levels and rescues spatial deficits in young rats after BDL. PMID:27445694

  9. Mitogen-activated protein kinase kinase 1/extracellular signal-regulated kinase (MEK-1/ERK) inhibitors sensitize reduced glucocorticoid response mediated by TNF{alpha} in human epidermal keratinocytes (HaCaT)

    SciTech Connect

    Onda, Kenji . E-mail: knjond@ps.toyaku.ac.jp; Nagashima, Masahiro; Kawakubo, Yo; Inoue, Shota; Hirano, Toshihiko; Oka, Kitaro

    2006-12-08

    Glucocorticoids (GCs) are essential drugs administered topically or systematically for the treatment of autoimmune skin diseases such as pemphigus. However, a certain proportion of patients does not respond well to GCs. Although studies on the relationship between cytokines and GC insensitivity in local tissues have attracted attention recently, little is known about the underlying mechanism(s) for GC insensitivity in epidermal keratinocytes. Here, we report that tumor necrosis factor (TNF) {alpha} reduces GC-induced transactivation of endogenous genes as well as a reporter plasmid which contains GC responsive element (GRE) in human epidermal keratinocyte cells (HaCaT). The GC insensitivity by TNF{alpha} was not accompanied by changes in mRNA expressions of GR isoforms ({alpha} or {beta}). However, we observed that mitogen-activated protein kinase kinase-1/extracellular signal-regulated kinase (MEK-1/ERK) inhibitors (PD98059 and U0126) significantly sensitized the GC-induced transactivation of anti-inflammatory genes (glucocorticoid-induced leucine zipper (GILZ) and mitogen-activated protein kinase phosphatase (MKP)-1) and FK506 binding protein (FKBP) 51 gene in the presence of TNF{alpha}. Additionally, we observed that TNF{alpha} reduced prednisolone (PSL)-dependent nuclear translocation of GR, which was restored by pre-treatment of MEK-1 inhibitors. This is the first study demonstrating a role of the MEK-1/ERK cascade in TNF{alpha}-mediated GC insensitivity. Our data suggest that overexpression of TNF{alpha} leads to topical GC insensitivity by reducing GR nuclear translocation in keratinocytes, and our findings also suggest that inhibiting the MEK-1/ERK cascade may offer a therapeutic potential for increasing GC efficacy in epidermis where sufficient inflammatory suppression is required.

  10. Prussian blue-gold nanoparticles-ionic liquid functionalized reduced graphene oxide nanocomposite as label for ultrasensitive electrochemical immunoassay of alpha-fetoprotein.

    PubMed

    Gao, Qi; Liu, Na; Ma, Zhanfang

    2014-06-01

    In this work, poly(diallyldimethylammonium chloride) (PDDA) protected Prussian blue/gold nanoparticles/ionic liquid functionalized reduced graphene oxide (IL-rGO-Au-PDDA-PB) nanocomposite was fabricated. The resulting nanocomposite exhibited high biocompatibility, conductivity and catalytic activity. To assess the performance of the nanocomposite, a sensitive sandwich-type immunosensor was constructed for detecting alpha-fetoprotein (AFP). Greatly enhanced sensitivity for this immunosensor was based on triple signal amplification strategies. Firstly, IL-rGO modified electrode was used as biosensor platform to capture a large amount of antibody due to its increased surface area, thus amplifying the detection response. Secondly, a large number of Au-PDDA-PB was conjugated on the surface of IL-rGO, which meant the enrichment of the signal and the more immobilization of label antibody. Finally, the catalytic reaction between H2O2 and the IL-rGO-Au-PDDA-PB nanocomposite further enhanced the signal response. The signals increased linearly with AFP concentrations in the range of 0.01-100 ng mL(-1). The detection limit for AFP was 4.6 pg mL(-1). The immunosensor showed high sensitivity, excellent selectivity and good stability. Moreover, the immunosensor was applied to the analysis of AFP in serum sample with satisfactory result. PMID:24856397

  11. Vanadium oxides on aluminum oxide supports. 1. Surface termination and reducibility of vanadia films on alpha-Al2O3(0001).

    PubMed

    Todorova, Tanya K; Ganduglia-Pirovano, M Veronica; Sauer, Joachim

    2005-12-15

    Using density functional theory and statistical thermodynamics, we obtained the phase diagram of thin VnOm films of varying thickness (approximately 2-6 A, 1-6 vanadium layers) supported on alpha-Al2O3(0001). Depending on the temperature, oxygen pressure, and vanadium concentration, films with different thickness and termination may form. In ultrahigh vacuum (UHV), at room temperature and for low vanadium concentrations, an ultrathin (1 x 1) O=V-terminated film is most stable. As more vanadium is supplied, the thickest possible films form. Their structures and terminations correspond to previous findings for the (0001) surface of bulk V2O3 [Kresse et al., Surf. Sci. 2004, 555, 118]. The presence of surface vanadyl (O=V) groups is a prevalent feature. They are stable up to at least 800 K in UHV. Vanadyl oxygen atoms induce a V(2p) core-level shift of about 2 eV on the surface V atoms. The reducibility of the supported films is characterized by the energy of oxygen defect formation. For the stable structures, the results vary between 4.11 and 3.59 eV per 1/2O2. In contrast, oxygen removal from the V2O5(001) surface is much easier (1.93 eV). This provides a possible explanation for the lower catalytic activity of vanadium oxides supported on alumina compared to that of crystalline vanadia particles. PMID:16375327

  12. Ru(bpy)32+/nanoporous silver-based electrochemiluminescence immunosensor for alpha fetoprotein enhanced by gold nanoparticles decorated black carbon intercalated reduced graphene oxide

    PubMed Central

    Zhu, Wenjuan; Lv, Xiaohui; Wang, Qi; Ma, Hongmin; Wu, Dan; Yan, Tao; Hu, Lihua; Du, Bin; Wei, Qin

    2016-01-01

    A highly sensitive sandwich-type electrochemiluminescence (ECL) immunosensor was proposed for the quantitative determination of alpha fetoprotein (AFP) using gold nanoparticles decorated black carbon intercalated reduced graphene oxide (Au-rGO@CB) as sensing platform and nanoporous silver (NPS) loaded Ru(bpy)32+ as labels. In this work, intercalation of CB inhibited the accumulation of rGO and Au-rGO@CB was firstly used to immobilize primary antibody (Ab1) in ECL system. NPS prepared by the dealloying of binary alloy has high pore volume and surface areas, which was used to load amount of secondary antibodies (Ab2) and Ru(bpy)32+, which could greatly enhance the ECL intensity. Under optimal conditions, the designed immunosensor exhibited wider linear range from 0.0001 to 30 ng/mL with a relative lower detection limit of 33 fg/mL for AFP detection. Overall, the designed immunosensor exhibited high sensitivity and selectivity, good repeatability and stability. This proposed method provided a potential application for clinical monitoring of AFP. PMID:26829062

  13. Reduced hippocampal volume and verbal memory performance associated with interleukin-6 and tumor necrosis factor-alpha levels in chemotherapy-treated breast cancer survivors

    PubMed Central

    Kesler, Shelli; Janelsins, Michelle; Koovakkattu, Della; Palesh, Oxana; Mustian, Karen; Morrow, Gary; Dhabhar, Firdaus S.

    2013-01-01

    Many survivors of breast cancer show significant cognitive impairments, including memory deficits. Inflammation induced by chemotherapy may contribute to hippocampal changes that underlie these deficits. In this cross-sectional study, we measured bilateral hippocampal volumes from high-resolution magnetic resonance images in 42 chemotherapy-treated breast cancer survivors and 35 healthy female controls. Patients with breast cancer were, on average, 4.8 ± 3.4 years off-therapy. In a subset of these participants (20 breast cancer, 23 controls), we quantified serum cytokine levels. Left hippocampal volumes and memory performance were significantly reduced and interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNFα) concentrations were significantly elevated in the breast cancer group compared to controls. In the breast cancer group, lower left hippocampal volume was associated with higher levels of TNFα and lower levels of IL-6 with a significant interaction between these two cytokines suggesting a potential modulatory effect of IL-6 on TNFα. Verbal memory performance was associated with cytokine levels and left hippocampal volume in both groups. These findings provide evidence of altered hippocampal volume and verbal memory difficulties following breast cancer chemotherapy that may be mediated by TNFα and IL-6. PMID:22698992

  14. On the maximal diphoton width

    NASA Astrophysics Data System (ADS)

    Salvio, Alberto; Staub, Florian; Strumia, Alessandro; Urbano, Alfredo

    2016-03-01

    Motivated by the 750 GeV diphoton excess found at LHC, we compute the maximal width into γγ that a neutral scalar can acquire through a loop of charged fermions or scalars as function of the maximal scale at which the theory holds, taking into account vacuum (meta)stability bounds. We show how an extra gauge symmetry can qualitatively weaken such bounds, and explore collider probes and connections with Dark Matter.

  15. THE LYMAN ALPHA MORPHOLOGY OF LOCAL STARBURST GALAXIES: RELEASE OF CALIBRATED IMAGES

    SciTech Connect

    Oestlin, Goeran; Hayes, Matthew; Kunth, Daniel; Atek, Hakim; Mas-Hesse, J. Miguel; Leitherer, Claus; Petrosian, Artashes E-mail: matthew.hayes@unige.ch

    2009-09-15

    We present reduced and calibrated high resolution Lyman-alpha (Ly{alpha}) images for a sample of six local star-forming galaxies. Targets were selected to represent a range in luminosity and metallicity and to include both known Ly{alpha} emitters and nonemitters. Far ultraviolet imaging was carried out with the Solar Blind Channel of the Advanced Camera for Surveys on the Hubble Space Telescope (HST) in the F122M (Ly{alpha} online) and F140LP (continuum) filters. The resulting Ly{alpha} images are the product of careful modeling of both the stellar and nebular continua, facilitated by supporting HST imaging at {lambda} {approx} 2200, 3300, 4400, 5500, H{alpha}, and 8000 A, combined with Starburst 99 evolutionary synthesis models, and prescriptions for dust extinction on the continuum. In all, the resulting morphologies in Ly{alpha}, H{alpha}, and UV continuum are qualitatively very different and we show that the bulk of Ly{alpha} emerges in a diffuse component resulting from resonant scattering events. Ly{alpha} escape fractions, computed from integrated H{alpha} luminosities and recombination theory, are found never to exceed 14%. Internal dust extinction is estimated in each pixel and used to correct Ly{alpha} fluxes. However, the extinction corrections are far too small (by factors from 2.6 to infinity) to reconcile the emerging global Ly{alpha} luminosities with standard recombination predictions. Surprisingly, when comparing the global equivalent widths of Ly{alpha} and H{alpha}, the two quantities appear to be anticorrelated, which may be due to the evolution of mechanical feedback from the starburst. This calls for caution in the interpretation of Ly{alpha} observations in terms of star formation rates. The images presented have a physical resolution 3 orders of magnitude better than attainable at high redshifts from the ground with current instrumentation and our images may therefore serve as useful templates for comparing with observations and modeling of

  16. Turner syndrome isochromosome karyotype correlates with decreased dental crown width.

    PubMed

    Rizell, S; Barrenäs, M-L; Andlin-Sobocki, A; Stecksén-Blicks, C; Kjellberg, H

    2012-04-01

    The aim of this project was to study possible influences of Turner syndrome (TS) karyotype and the number of X chromosomes with intact short arm (p-arm) on dental crown width. Primary and permanent mesio-distal crown width was measured on plaster casts from 112 TS females. The influence on crown width of four karyotypes: 1. monosomy (45,X), 2. mosaic (45,X/46,XX), 3. isochromosome, and 4. other, and the number of intact X chromosomal p-arms were investigated. In comparisons between karyotypes, statistically significant differences were found for isochromosome karyotype maxillary second premolars, canines, laterals, mandibular first premolars, and canines, indicating that this karyotype was the most divergent as shown by the most reduced crown width. When each karyotype group were compared versus controls, all teeth in the isochromosome group were significantly smaller than controls (P < 0.01-0.001). The 45,X/46,XX karyotype expressed fewer and smaller differences from controls, while 45,X individuals seemed to display an intermediate tooth width compared with 45,X/46,XX and isochromosomes. No significant difference in crown width was found comparing the groups with one or two intact X chromosomal p-arms. Both primary and permanent teeth proved to have a significantly smaller crown width in the entire group of TS females compared to healthy females. We conclude that the isochromosome group deviates most from other karyotypes and controls, exhibiting the smallest dental crown width, while individuals with 45,X/46,XX mosaicism seemed to have a less affected crown width. An influence of the number of intact p-arms on crown width could not be demonstrated in this study. PMID:21303812

  17. The dopamine uptake inhibitor 3 alpha-[bis(4'-fluorophenyl)metoxy]-tropane reduces cocaine-induced early-gene expression, locomotor activity, and conditioned reward.

    PubMed

    Velázquez-Sánchez, Clara; Ferragud, Antonio; Hernández-Rabaza, Vicente; Nácher, Amparo; Merino, Virginia; Cardá, Miguel; Murga, Juan; Canales, Juan J

    2009-11-01

    Benztropine (BZT) analogs, a family of high-affinity dopamine transporter ligands, are molecules that exhibit pharmacological and behavioral characteristics predictive of significant therapeutic potential in cocaine addiction. Here, we examined in mice the effects of 3 alpha-[bis(4'-fluorophenyl)metoxy]-tropane (AHN-1055) on motor activity, conditioned place preference (CPP) and c-Fos expression in the striatum. AHN-1055 produced mild attenuation of spontaneous locomotor activity at a low dose (1 mg/kg) and weak stimulation at a higher dose (10 mg/kg). In parallel, the BZT analog significantly increased c-Fos expression in the dorsolateral caudoputamen at the high dose, whereas producing marginal decreases at low and moderate doses (1, 3 mg/kg) in both dorsal and ventral striatum. Interaction assays showed that cocaine's ability to stimulate locomotor activity was decreased by AHN-1055 treatment, but not by treatment with D-amphetamine. Such reduced ability did not result from an increase in stereotyped behavior. Another dopamine uptake inhibitor, nomifensine, decreased cocaine-induced locomotor activity but evoked by itself intense motor stereotypies. Remarkably, the BZT analog dose-dependently blocked cocaine-induced CPP without producing CPP when given alone, and blocked in conditioned mice cocaine-stimulated early-gene activation in the nucleus accumbens and dorsomedial striatum. These observations provide evidence that AHN-1055 does not behave as a classical psychomotor stimulant and that some of its properties, including attenuation of cocaine-induced striatal c-Fos expression, locomotor stimulation, and CPP, support its candidacy, and that of structurally related molecules, as possible pharmacotherapies in cocaine addiction. PMID:19606084

  18. Modulation of gene expression by alpha-tocopherol and alpha-tocopheryl phosphate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The naturally occurring vitamin E analogue, alpha-tocopheryl phosphate (alphaTP), has been reported to be more potent in reducing cell proliferation and the expression of the CD36 scavenger receptor than the un-phosphorylated alpha-tocopherol (alpha T). We have now assessed the effects of alpha T an...

  19. Alpha Particle

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Term that is sometimes used to describe a helium nucleus, a positively charged particle that consists of two protons and two neutrons, bound together. Alpha particles, which were discovered by Ernest Rutherford (1871-1937) in 1898, are emitted by atomic nuclei that are undergoing alpha radioactivity. During this process, an unstable heavy nucleus spontaneously emits an alpha particle and transmut...

  20. 14 CFR 121.95 - Route width.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., FLAG, AND SUPPLEMENTAL OPERATIONS Approval of Routes: Domestic and Flag Operations § 121.95 Route width... routes in the case of certificate holders conducting flag operations) have a width equal to...

  1. 23 CFR 658.15 - Width.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS TRUCK SIZE AND WEIGHT, ROUTE DESIGNATIONS-LENGTH, WIDTH AND WEIGHT LIMITATIONS § 658.15 Width. (a) No State shall impose a width limitation of more or less than 102 inches, or its approximate metric equivalent, 2.6 meters (102.36 inches)...

  2. 23 CFR 658.15 - Width.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS TRUCK SIZE AND WEIGHT, ROUTE DESIGNATIONS-LENGTH, WIDTH AND WEIGHT LIMITATIONS § 658.15 Width. (a) No State shall impose a width limitation of more or less than 102 inches, or its approximate metric equivalent, 2.6 meters (102.36 inches)...

  3. 23 CFR 658.15 - Width.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS TRUCK SIZE AND WEIGHT, ROUTE DESIGNATIONS-LENGTH, WIDTH AND WEIGHT LIMITATIONS § 658.15 Width. (a) No State shall impose a width limitation of more or less than 102 inches, or its approximate metric equivalent, 2.6 meters (102.36 inches)...

  4. 23 CFR 658.15 - Width.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS TRUCK SIZE AND WEIGHT, ROUTE DESIGNATIONS-LENGTH, WIDTH AND WEIGHT LIMITATIONS § 658.15 Width. (a) No State shall impose a width limitation of more or less than 102 inches, or its approximate metric equivalent, 2.6 meters (102.36 inches)...

  5. 23 CFR 658.15 - Width.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION ENGINEERING AND TRAFFIC OPERATIONS TRUCK SIZE AND WEIGHT, ROUTE DESIGNATIONS-LENGTH, WIDTH AND WEIGHT LIMITATIONS § 658.15 Width. (a) No State shall impose a width limitation of more or less than 102 inches, or its approximate metric equivalent, 2.6 meters (102.36 inches)...

  6. Adenovirus-Mediated Expression of Interferon-Alpha Delays Viral Replication and Reduces Disease Signs in Swine Challenged with Porcine Reproductive and Respiratory Syndrome Virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, pigs were injected with a nonreplicating human adenovirus type 5 vector expressing porcine interferon-alpha (Ad5-pIFNa) and then challenged with porcine reproductive and respiratory syndrome virus (PRRSV) to determine whether the presence of increased levels of IFNa would decrease vir...

  7. Presence of interferon-alpha delays viral replication and reduces disease signs in pigs challenged with porcine reproductive and respiratory syndrome virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Compared to other viruses that infect the respiratory system, porcine reproductive and respiratory syndrome virus (PRRSV) appears to induce only modest levels of interferon-alpha (IFNA). However, IFNA has been shown to inhibit PRRSV replication in vitro, and indirectly to inhibit replication in viv...

  8. Intraspecific competition reduces niche width in experimental populations

    PubMed Central

    Parent, Christine E; Agashe, Deepa; Bolnick, Daniel I

    2014-01-01

    Intraspecific competition is believed to drive niche expansion, because otherwise suboptimal resources can provide a refuge from competition for preferred resources. Competitive niche expansion is well supported by empirical observations, experiments, and theory, and is often invoked to explain phenotypic diversification within populations, some forms of speciation, and adaptive radiation. However, some foraging models predict the opposite outcome, and it therefore remains unclear whether competition will promote or inhibit niche expansion. We conducted experiments to test whether competition changes the fitness landscape to favor niche expansion, and if competition indeed drives niche expansion as expected. Using Tribolium castaneum flour beetles fed either wheat (their ancestral resource), corn (a novel resource) or mixtures of both resources, we show that fitness is maximized on a mixed diet. Next, we show that at higher population density, the optimal diet shifts toward greater use of corn, favoring niche expansion. In stark contrast, when beetles were given a choice of resources, we found that competition caused niche contraction onto the ancestral resource. This presents a puzzling mismatch between how competition alters the fitness landscape, versus competition's effects on resource use. We discuss several explanations for this mismatch, highlighting potential reasons why optimality models might be misleading. PMID:25505525

  9. Intraspecific competition reduces niche width in experimental populations.

    PubMed

    Parent, Christine E; Agashe, Deepa; Bolnick, Daniel I

    2014-10-01

    Intraspecific competition is believed to drive niche expansion, because otherwise suboptimal resources can provide a refuge from competition for preferred resources. Competitive niche expansion is well supported by empirical observations, experiments, and theory, and is often invoked to explain phenotypic diversification within populations, some forms of speciation, and adaptive radiation. However, some foraging models predict the opposite outcome, and it therefore remains unclear whether competition will promote or inhibit niche expansion. We conducted experiments to test whether competition changes the fitness landscape to favor niche expansion, and if competition indeed drives niche expansion as expected. Using Tribolium castaneum flour beetles fed either wheat (their ancestral resource), corn (a novel resource) or mixtures of both resources, we show that fitness is maximized on a mixed diet. Next, we show that at higher population density, the optimal diet shifts toward greater use of corn, favoring niche expansion. In stark contrast, when beetles were given a choice of resources, we found that competition caused niche contraction onto the ancestral resource. This presents a puzzling mismatch between how competition alters the fitness landscape, versus competition's effects on resource use. We discuss several explanations for this mismatch, highlighting potential reasons why optimality models might be misleading. PMID:25505525

  10. Limit Cycles Can Reduce the Width of the Habitable Zone

    NASA Astrophysics Data System (ADS)

    Haqq-Misra, Jacob; Kopparapu, Ravi Kumar; Batalha, Natasha E.; Harman, Chester E.; Kasting, James F.

    2016-08-01

    The liquid water habitable zone (HZ) describes the orbital distance at which a terrestrial planet can maintain above-freezing conditions through regulation by the carbonate-silicate cycle. Recent calculations have suggested that planets in the outer regions of the HZ cannot maintain stable, warm climates, but rather should oscillate between long, globally glaciated states and shorter periods of climatic warmth. Such conditions, similar to “Snowball Earth” episodes experienced on Earth, would be inimical to the development of complex land life, including intelligent life. Here, we build on previous studies with an updated energy balance climate model to calculate this “limit cycle” region of the HZ where such cycling would occur. We argue that an abiotic Earth would have a greater CO2 partial pressure than today because plants and other biota help to enhance the storage of CO2 in soil. When we tune our abiotic model accordingly, we find that limit cycles can occur but that previous calculations have overestimated their importance. For G stars like the Sun, limit cycles occur only for planets with CO2 outgassing rates less than that on modern Earth. For K- and M-star planets, limit cycles should not occur; however, M-star planets may be inhospitable to life for other reasons. Planets orbiting late G-type and early K-type stars retain the greatest potential for maintaining warm, stable conditions. Our results suggest that host star type, planetary volcanic activity, and seafloor weathering are all important factors in determining whether planets will be prone to limit cycling.

  11. Alpha-thalassaemia.

    PubMed

    Harteveld, Cornelis L; Higgs, Douglas R

    2010-01-01

    Alpha-thalassaemia is inherited as an autosomal recessive disorder characterised by a microcytic hypochromic anaemia, and a clinical phenotype varying from almost asymptomatic to a lethal haemolytic anaemia.It is probably the most common monogenic gene disorder in the world and is especially frequent in Mediterranean countries, South-East Asia, Africa, the Middle East and in the Indian subcontinent. During the last few decades the incidence of alpha thalassaemia in North-European countries and Northern America has increased because of demographic changes. Compound heterozygotes and some homozygotes have a moderate to severe form of alpha thalassaemia called HbH disease. Hb Bart's hydrops foetalis is a lethal form in which no alpha-globin is synthesized. Alpha thalassaemia most frequently results from deletion of one or both alpha genes from the chromosome and can be classified according to its genotype/phenotype correlation. The normal complement of four functional alpha-globin genes may be decreased by 1, 2, 3 or all 4 copies of the genes, explaining the clinical variation and increasing severity of the disease. All affected individuals have a variable degree of anaemia (low Hb), reduced mean corpuscular haemoglobin (MCH/pg), reduced mean corpuscular volume (MCV/fl) and a normal/slightly reduced level of HbA2. Molecular analysis is usually required to confirm the haematological observations (especially in silent alpha-thalassaemia and alpha-thalassaemia trait). The predominant features in HbH disease are anaemia with variable amounts of HbH (0.8-40%). The type of mutation influences the clinical severity of HbH disease. The distinguishing features of the haemoglobin Bart's hydrops foetalis syndrome are the presence of Hb Bart's and the total absence of HbF. The mode of transmission of alpha thalassaemia is autosomal recessive. Genetic counselling is offered to couples at risk for HbH disease or haemoglobin Bart's Hydrops Foetalis Syndrome. Carriers of alpha+- or

  12. Binding of tumor necrosis factor alpha to activated forms of human plasma alpha 2 macroglobulin.

    PubMed Central

    Wollenberg, G. K.; LaMarre, J.; Rosendal, S.; Gonias, S. L.; Hayes, M. A.

    1991-01-01

    We tested the hypothesis that human plasma alpha 2 macroglobulin (alpha 2M) is a latent binding glycoprotein for human tumor necrosis factor alpha (TNF-alpha). Human recombinant 125I-TNF-alpha was incubated for 2 hours (37 degrees C) with purified native alpha 2M and with alpha 2M that was modified by reaction with methylamine or various proteinases. 125I-TNF-alpha/alpha 2M complexes were detected by nondenaturing polyacrylamide gel electrophoresis after autoradiography or by liquid chromatography on Superose-6. 125I-TNF-alpha bound strongly but noncovalently to alpha 2M-plasmin and alpha 2M-methylamine. There was minimal binding of 125I-TNF-alpha to native alpha 2M, alpha 2M-trypsin, or alpha 2M-thrombin. A 10(6) molar excess of porcine heparin did not reduce the binding of 125I-TNF-alpha to alpha 2M-methylamine or alpha 2M-plasmin. alpha 2M-plasmin or alpha 2M-methylamine added to human plasma or serum preferentially bound 125I-TNF-alpha in the presence of native alpha 2M. 125I-TNF-alpha also bound to 'fast' alpha-macroglobulins in methylamine-reacted human, rat, mouse, swine, equine, and bovine plasma. However, TNF-alpha, preincubated with either alpha 2M-plasmin or alpha 2M-methylamine, remained a potent necrogen for cultured L929 cells. Purified 125I-TNF-alpha/alpha 2M-plasmin complex injected intravenously in CD-1 mice rapidly cleared from the circulation, unless the alpha 2M-receptor pathway was blocked by coinjection of excess alpha 2M-trypsin. These findings demonstrate that alpha 2M is a latent plasmin-activated binding glycoprotein for TNF-alpha and that TNF-alpha/alpha 2M-plasmin complexes can be removed from the circulation by the alpha 2M-receptor pathway. This suggests that alpha 2M may be an important regulator of the activity and distribution of TNF-alpha in vivo. Images Figure 1 Figure 3 PMID:1704186

  13. Width of the level at E sub x congruent 18 MeV in sup 5 Li

    SciTech Connect

    Arena, N.; Cavallaro, S. Istituto Nazionale di Fisica Nucleare, Sezione di Catania, Catania, Italy); D'Arrigo, A.; Fazio, G.; Giardina, G.; Italiano, A.; Herman, M.; Lombardi, M.

    1989-09-01

    The {alpha}{alpha} bidimensional spectra for the {sup 6}Li({sup 3}He, {alpha}{ital p}){sup 4}He reaction at 11, 13, and 14 MeV incident energy have been measured. The {sup 5}Li state at {ital E}{sub {ital x}}=(17.9{plus minus}0.4) MeV has been observed and its width has been determined as (3.5{plus minus}0.8) MeV. The excitation energy is in line with the shell-model calculations while the {Gamma} value is the first quantitative estimate of the width of the above state.

  14. Red cell distribution width and nonalcoholic steatohepatitis

    PubMed Central

    Gulcan Kurt, Yasemin; Cayci, Tuncer; Aydin, Fevzi Nuri; Agilli, Mehmet

    2014-01-01

    Red cell distribution width is a measure of deviation of the volume of red blood cells. It is a marker of anisocytosis and often used to evaluate the possible causes of anemia. Elevated red cell distribution width levels are also associated with acute and chronic inflammatory responses. In nonalcoholic steatohepatitis, inflammation is accompanied with steatosis. For assuming red cell distribution width as a marker of nonalcoholic steatohepatitis, intervening factors such as levels of inflammatory markers should also be evaluated. PMID:25473202

  15. Optically thick line widths in pyrotechnic flares

    NASA Technical Reports Server (NTRS)

    Douda, B. E.; Exton, R. J.

    1975-01-01

    Experimentally determined sodium line widths for pyrotechnic flares are compared with simple analytical, optically-thick-line-shape calculations. Three ambient pressure levels are considered (760, 150 and 30 torr) for three different flare compositions. The measured line widths range from 1.3 to 481 A. The analytic procedure emphasizes the Lorentz line shape as observed under optically-thick conditions. Calculated widths are in good agreement with the measured values over the entire range.

  16. Elevated red blood cell distribution width and inflammation in printing workers

    PubMed Central

    Celik, Ahmet; Aydin, Neriman; Ozcirpici, Birgul; Saricicek, Edibe; Sezen, Hatice; Okumus, Mehmet; Bozkurt, Selim; Kilinc, Metin

    2013-01-01

    Background The aim of this study was to estimate the effects of exposure to chemical compounds on systemic biochemical inflammatory markers in printing industry workers. Material/Methods Fifty-eight printing workers from 19 different small- and medium-sized enterprises in the printing sector were investigated. For comparison, 80 healthy workers not subjected to workplace chemicals served as control subjects. Results No significant differences were observed between the printing workers and control subjects with respect to age, BMI, waist circumference/hip circumference ratio, smoking, and alcohol consumption. Printing workers had significantly higher serum TNF-alpha levels (11.02±5.34 vs. 9.26±3.87 pg/ml, p=0.039), plasma fibrinogen levels (1.74±0.49 vs. 1.38±0.5 mg/dl, p=0.012), and red blood cell distribution width (RDW-SD) (49.77±3.09 vs. 47.3±2.88 p<0.01) compared to control subjects. Conclusions Elevation of RDW, serum TNF-alpha, and plasma fibrinogen levels in printing workers may be due to systemic toxic effects of chemical compounds used in this sector. TNF-alpha is an inflammatory cytokine that has a wide spectrum of biological activities, and fibrinogen plays an important role in pathological processes. Some compounds may be carcinogenic or mutagenic. Better designed workplaces and working conditions will help to reduce the hazardous effects of chemical compounds. PMID:24231719

  17. Reduced pancreatic polypeptide response to hypoglycemia and amylin response to arginine in subjects with a mutation in the HNF-4alpha/MODY1 gene.

    PubMed

    Ilag, L L; Tabaei, B P; Herman, W H; Zawacki, C M; D'Souza, E; Bell, G I; Fajans, S S

    2000-06-01

    Subjects with the Q268X mutation in the hepatocyte nuclear factor (HNF)-4alpha gene (RW pedigree/maturity-onset diabetes of the young [MODY]-1) have diminished insulin and glucagon secretory responses to arginine. To determine if pancreatic polypeptide (PP) secretion is likewise involved, we studied PP responses to insulin-induced hypoglycemia in 17 RW pedigree members: 6 nondiabetic mutation-negative [ND(-)], 4 nondiabetic mutation-positive [ND(+)], and 7 diabetic mutation-positive [D(+)]. Subjects received 0.08 U/kg body wt human regular insulin as an intravenous bolus to produce moderate self-limited hypoglycemia. PP areas under the curve (PP-AUCs) were compared among groups. With hypoglycemia, the PP-AUC was lower in the D(+) group (14,907 +/- 6,444 pg/ml, P = 0.03) and the ND(+) group (14,622 +/- 6,015 pg/ml, P = 0.04) compared with the ND(-) group (21,120 +/- 4,158 pg/ml). In addition, to determine if the beta-cell secretory defect in response to arginine involves amylin in addition to insulin secretion, we analyzed samples from 17 previously studied RW pedigree subjects. We compared the AUCs during arginine infusions for the 3 groups both at euglycemia and hyperglycemia as well as their C-peptide-to-amylin ratios. The D(+) and ND(+) groups had decreased amylin AUCs during both arginine infusions compared with the ND(-) group, but had similar C-peptide-to-amylin ratios. These results suggest that the HNF-4alpha mutation in the RW/MODY1 pedigree confers a generalized defect in islet cell function involving PP cells in addition to beta- and alpha-cells, and beta-cell impairment involving proportional deficits in insulin and amylin secretion. PMID:10866048

  18. Alpha Thalassemia

    MedlinePlus

    ... an apparently normal individual has a child with hemoglobin H disease or alpha thalassemia minor. It can ... gene on one chromosome 25% 25% 25% 25% hemoglobin H disease there is a 25% chance with ...

  19. Discovery of {sup 109}Xe and {sup 105}Te: Superallowed {alpha} Decay near Doubly Magic {sup 100}Sn

    SciTech Connect

    Liddick, S. N.; Batchelder, J. C.; Grzywacz, R.; Bingham, C. R.; Mazzocchi, C.; Drafta, G.; Tantawy, M. N.; Page, R. D.; Darby, I. G.; Joss, D. T.; Thomson, J.; Rykaczewski, K. P.; Gross, C. J.; Goodin, C.; Hamilton, J. H.; Hwang, J. K.; Li, K.; Hecht, A. A.; Ilyushkin, S.; Korgul, A.

    2006-08-25

    Two new {alpha} emitters {sup 109}Xe and {sup 105}Te were identified through the observation of the {sup 109}Xe{yields}{sup 105}Te{yields}{sup 101}Sn {alpha}-decay chain. The {sup 109}Xe nuclei were produced in the fusion-evaporation reaction {sup 54}Fe({sup 58}Ni,3n){sup 109}Xe and studied using the Recoil Mass Spectrometer at the Holifield Radioactive Ion Beam Facility. Two transitions at E{sub {alpha}}=4062{+-}7 keV and E{sub {alpha}}=3918{+-}9 keV were interpreted as the l=2 and l=0 transitions from the 7/2{sup +} ground state in {sup 109}Xe (T{sub 1/2}=13{+-}2 ms) to the 5/2{sup +} ground state and a 7/2{sup +} excited state, located at 150{+-}13 keV in {sup 105}Te. The observation of the subsequent decay of {sup 105}Te marks the discovery of the lightest known {alpha}-decaying nucleus. The measured transition energy E{sub {alpha}}=4703{+-}5 keV and half-life T{sub 1/2}=620{+-}70 ns were used to determine the reduced {alpha}-decay width {delta}{sup 2}. The ratio {delta}{sub {sup 105}Te}{sup 2}/{delta}{sub {sup 213}Po}{sup 2} of {approx}3 indicates a superallowed character of the {alpha} emission from {sup 105}Te.

  20. Development of crash modification factors for changing lane width on roadway segments using generalized nonlinear models.

    PubMed

    Lee, Chris; Abdel-Aty, Mohamed; Park, Juneyoung; Wang, Jung-Han

    2015-03-01

    This study evaluates the effectiveness of changing lane width in reducing crashes on roadway segments. To consider nonlinear relationships between crash rate and lane width, the study develops generalized nonlinear models (GNMs) using 3-years crash records and road geometry data collected for all roadway segments in Florida. The study also estimates various crash modification factors (CMFs) for different ranges of lane width based on the results of the GNMs. It was found that the crash rate was highest for 12-ft lane and lower for the lane width less than or greater than 12ft. GNMs can extrapolate this nonlinear continuous effect of lane width and estimate the CMFs for any lane width, not only selected lane widths, unlike generalized linear models (GLMs) with categorical variables. The CMFs estimated using GNMs reflect that crashes are less likely to occur for narrower lanes if the lane width is less than 12ft whereas crashes are less likely to occur for wider lanes if the lane width is greater than 12ft. However, these effects varied with the posted speed limits as the effect of interaction between lane width and speed limit was significant. The estimated CMFs show that crashes are less likely to occur for lane widths less than 12ft than the lane widths greater than 12ft if the speed limit is higher than or equal to 40mph. It was also found from the CMFs that crashes at higher severity levels (KABC and KAB) are less likely to occur for lane widths greater or less than 12ft compared to 12-ft lane. The study demonstrates that the CMFs estimated using GNMs clearly reflect variations in crashes with lane width, which cannot be captured by the CMFs estimated using GLMs. Thus, it is recommended that if the relationship between crash rate and lane width is nonlinear, the CMFs are estimated using GNMs. PMID:25616033

  1. Critical comparison of Kramers' fission width with the stationary width from the Langevin equation

    SciTech Connect

    Sadhukhan, Jhilam; Pal, Santanu

    2009-06-15

    It is shown that Kramers' fission width, originally derived for a system with constant inertia, can be extended to systems with a deformation-dependent collective inertia, which is the case for nuclear fission. The predictions of Kramers' width for systems with variable inertia are found to be in very good agreement with the stationary fission widths obtained by solving the corresponding Langevin equations.

  2. Background canceling surface alpha detector

    DOEpatents

    MacArthur, Duncan W.; Allander, Krag S.; Bounds, John A.

    1996-01-01

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone.

  3. Background canceling surface alpha detector

    DOEpatents

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

    1996-06-11

    A background canceling long range alpha detector which is capable of providing output proportional to both the alpha radiation emitted from a surface and to radioactive gas emanating from the surface. The detector operates by using an electrical field between first and second signal planes, an enclosure and the surface or substance to be monitored for alpha radiation. The first and second signal planes are maintained at the same voltage with respect to the electrically conductive enclosure, reducing leakage currents. In the presence of alpha radiation and radioactive gas decay, the signal from the first signal plane is proportional to both the surface alpha radiation and to the airborne radioactive gas, while the signal from the second signal plane is proportional only to the airborne radioactive gas. The difference between these two signals is proportional to the surface alpha radiation alone. 5 figs.

  4. The Apollo Alpha Spectrometer.

    NASA Technical Reports Server (NTRS)

    Jagoda, N.; Kubierschky, K.; Frank, R.; Carroll, J.

    1973-01-01

    Located in the Science Instrument Module of Apollo 15 and 16, the Alpha Particle Spectrometer was designed to detect and measure the energy of alpha particles emitted by the radon isotopes and their daughter products. The spectrometer sensor consisted of an array of totally depleted silicon surface barrier detectors. Biased amplifier and linear gate techniques were utilized to reduce resolution degradation, thereby permitting the use of a single 512 channel PHA. Sensor identification and in-flight radioactive calibration were incorporated to enhance data reduction.

  5. Tetrahydro Iso-Alpha Acids and Hexahydro Iso-Alpha Acids from Hops Inhibit Proliferation of Human Hepatocarcinoma Cell Lines and Reduce Diethylnitrosamine Induced Liver Tumor Formation in Rats.

    PubMed

    Stärkel, Peter; De Saeger, Christine; Delire, Bénédicte; Magat, Julie; Jordan, Bénédicte; Konda, Veera R; Tripp, Mathew L; Borbath, Ivan

    2015-01-01

    Chronic inflammation plays important role in the pathogenesis of hepatocellular carcinoma (HCC). To date, no antiinflammatory approach has shown its efficacy in preventing HCC occurrence in humans. Because tetra- and hexahydro isoalpha acids (THIAA and HHIAA) from hops elicit antiinflammatory properties, we evaluated these compounds for antitumor effects in vitro in human HCC cell lines (HepG2, Hep3B, Huh7) and in vivo in diethylnitrosamine (DEN)-induced animal model of HCC. In human HCC cell lines, THIAA and HHIAA reduced cell proliferation and viability which was associated with the inhibition of the NF-κB-DNA binding and tumor necrosis factor α mRNA expression. Both compounds also inhibited phosphorylation of the mTOR effector p70S6 kinase without affecting ERK, AKT, JNK, and GSK3β phosphorylation or activator protein-1 activation. In DEN-treated rats, administration of THIAA and HHIAA in food reduced the tumor numbers and the expression of the cellular transformation marker glutathione-S-transferase in the liver. In conclusion, THIAA and HHIAA show antitumor properties in vitro in human HCC cell lines as well as in vivo in a chemically induced animal model of HCC. PMID:25941903

  6. Bipartite Graphs of Large Clique-Width

    NASA Astrophysics Data System (ADS)

    Korpelainen, Nicholas; Lozin, Vadim V.

    Recently, several constructions of bipartite graphs of large clique-width have been discovered in the literature. In the present paper, we propose a general framework for developing such constructions and use it to obtain new results on this topic.

  7. You can't stop the music: reduced auditory alpha power and coupling between auditory and memory regions facilitate the illusory perception of music during noise.

    PubMed

    Müller, Nadia; Keil, Julian; Obleser, Jonas; Schulz, Hannah; Grunwald, Thomas; Bernays, René-Ludwig; Huppertz, Hans-Jürgen; Weisz, Nathan

    2013-10-01

    Our brain has the capacity of providing an experience of hearing even in the absence of auditory stimulation. This can be seen as illusory conscious perception. While increasing evidence postulates that conscious perception requires specific brain states that systematically relate to specific patterns of oscillatory activity, the relationship between auditory illusions and oscillatory activity remains mostly unexplained. To investigate this we recorded brain activity with magnetoencephalography and collected intracranial data from epilepsy patients while participants listened to familiar as well as unknown music that was partly replaced by sections of pink noise. We hypothesized that participants have a stronger experience of hearing music throughout noise when the noise sections are embedded in familiar compared to unfamiliar music. This was supported by the behavioral results showing that participants rated the perception of music during noise as stronger when noise was presented in a familiar context. Time-frequency data show that the illusory perception of music is associated with a decrease in auditory alpha power pointing to increased auditory cortex excitability. Furthermore, the right auditory cortex is concurrently synchronized with the medial temporal lobe, putatively mediating memory aspects associated with the music illusion. We thus assume that neuronal activity in the highly excitable auditory cortex is shaped through extensive communication between the auditory cortex and the medial temporal lobe, thereby generating the illusion of hearing music during noise. PMID:23664946

  8. Alpha-tocopherol quinine ameliorates spatial memory deficits by reducing beta-amyloid oligomers, neuroinflammation and oxidative stress in transgenic mice with Alzheimer's disease.

    PubMed

    Wang, Shao-Wei; Yang, Shi-Gao; Liu, Wen; Zhang, Yang-Xin; Xu, Peng-Xin; Wang, Teng; Ling, Tie-Jun; Liu, Rui-Tian

    2016-01-01

    The pathologies of Alzheimer's disease (AD) is associated with soluble beta-amyloid (Aβ) oligomers, neuroinflammation and oxidative stress. Decreasing the levels of Aβ oligomer, glial activation and oxidative stress are potential therapeutic approaches for AD treatment. We previously found alpha-tocopherol quinine (α-TQ) inhibited Aβ aggregation and cytotoxicity, decreased the release of inflammatory cytokines and reactive oxygen species (ROS) in vitro. However, whether α-TQ ameliorates memory deficits and other neuropathologies in mice or patients with AD remains unknown. In this study, we reported that orally administered α-TQ ameliorated memory impairment in APPswe/PS1dE9 transgenic mice, decreased oxidative stress and the levels of Aβ oligomer in the brains of mice, prevented the production of inducible nitric oxide synthase and inflammatory mediators, such as interleukin-6 and interleukin-1β, and inhibited microglial activation by inhibiting NF-κB signaling pathway. These findings suggest that α-TQ has potential therapeutic value for AD treatment. PMID:26358659

  9. Finite banana width effect on magnetoacoustic cyclotron instability

    SciTech Connect

    Chen, Y.P.; Tsai, S.T.

    1995-08-01

    The finite banana width (FBW) effect on the coupling between magnetoacoustic waves and the near harmonic gyro-oscillations of the energetic ions/{alpha} particles in tokamaks are studied. The gyrokinetic equation with FBW effect is rederived for the energetic trapped ions. The dispersion relation and growth rate of the magnetoacoustic cyclotron instability (MACI) are obtained. It is found that the coherence interaction between the energetic ion trajectory and mode field has a significant effect when the Larmor radius of energetic ions is larger than the wavelength of MACI. Near the low field side the FBW effect destabilizes the mode, while away from it the FBW gives a stabilizing effect. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

  10. Reanalysis of nuclear level widths from particle--x-ray coincidence experiments

    SciTech Connect

    Amund Amundsen, P.; Dost, M.

    1986-03-01

    Using new theoretical values for the ionization probabilities during the incoming part of a collision, we have reanalyzed the mean nuclear level widths obtained by the particle-x-ray coincidence method. We find that the deduced level widths are substantially reduced.

  11. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... Liver Disease Information > Alpha-1 Antitrypsin Deficiency Alpha-1 Antitrypsin Deficiency Explore this section to learn more about alpha-1 antitrypsin deficiency, including a description of the disorder ...

  12. Alpha-Lipoic Acid Reduces LDL-Particle Number and PCSK9 Concentrations in High-Fat Fed Obese Zucker Rats

    PubMed Central

    Carrier, Bradley; Wen, Shin; Zigouras, Sophia; Browne, Richard W.; Li, Zhuyun; Patel, Mulchand S.; Williamson, David L.; Rideout, Todd C.

    2014-01-01

    We characterized the hypolipidemic effects of alpha-lipoic acid (LA, R-form) and examined the associated molecular mechanisms in a high fat fed Zucker rat model. Rats (n = 8) were assigned to a high fat (HF) diet or the HF diet with 0.25% LA (HF-LA) for 30 days and pair fed to remove confounding effects associated with the anorectic properties of LA. Compared with the HF controls, the HF-LA group was protected against diet-induced obesity (102.5±3.1 vs. 121.5±3.6,% change BW) and hypercholesterolemia with a reduction in total-C (−21%), non-HDL-C (−25%), LDL-C (−16%), and total LDL particle number (−46%) and an increase in total HDL particles (∼22%). This cholesterol-lowering response was associated with a reduction in plasma PCSK9 concentration (−70%) and an increase in hepatic LDLr receptor protein abundance (2 fold of HF). Compared with the HF-fed animals, livers of LA-supplemented animals were protected against TG accumulation (−46%), likely through multiple mechanisms including: a suppressed lipogenic response (down-regulation of hepatic acetyl-CoA carboxylase and fatty acid synthase expression); enhanced hepatic fat oxidation (increased carnitine palmitoyltransferase Iα expression); and enhanced VLDL export (increased hepatic diacylglycerol acyltransferase and microsomal triglyceride transfer protein expression and elevated plasma VLDL particle number). Study results also support an enhanced fatty acid uptake (2.8 fold increase in total lipase activity) and oxidation (increased CPT1β protein abundance) in muscle tissue in LA-supplemented animals compared with the HF group. In summary, in the absence of a change in caloric intake, LA was effective in protecting against hypercholesterolemia and hepatic fat accumulation under conditions of strong genetic and dietary predisposition toward obesity and dyslipidemia. PMID:24595397

  13. Solution conformation of a neuronal nicotinic acetylcholine receptor antagonist {alpha}-conotoxin OmIA that discriminates {alpha}3 vs. {alpha}6 nAChR subtypes

    SciTech Connect

    Chi, Seung-Wook; Kim, Do-Hyoung; Olivera, Baldomero M.; McIntosh, J. Michael; Han, Kyou-Hoon . E-mail: khhan600@kribb.re.kr

    2006-06-23

    {alpha}-Conotoxin OmIA from Conus omaria is the only {alpha}-conotoxin that shows a {approx}20-fold higher affinity to the {alpha}3{beta}2 over the {alpha}6{beta}2 subtype of nicotinic acetylcholine receptor. We have determined a three-dimensional structure of {alpha}-conotoxin OmIA by nuclear magnetic resonance spectroscopy. {alpha}-Conotoxin OmIA has an '{omega}-shaped' overall topology with His{sup 5}-Asn{sup 12} forming an {alpha}-helix. Structural features of {alpha}-conotoxin OmIA responsible for its selectivity are suggested by comparing its surface characteristics with other functionally related {alpha}4/7 subfamily conotoxins. Reduced size of the hydrophilic area in {alpha}-conotoxin OmIA seems to be associated with the reduced affinity towards the {alpha}6{beta}2 nAChR subtype.

  14. Bayesian Identification of Emission-Line Galaxies with Photometric Equivalent Widths

    NASA Astrophysics Data System (ADS)

    Leung, Andrew S.; Gawiser, Eric J.; Acquaviva, Viviana; HETDEX Collaboration

    2015-01-01

    We present a Bayesian approach to the classification of emission-line galaxies as an alternative to the traditional limit of requiring Lyman-alpha emitting (LAE) galaxies to have rest-frame equivalent width (EW) > 20Å. The Bayesian method relies on known distributions of line luminosities and equivalent widths as prior probabilities and returns the probability that an object is an LAE given the observed characteristics. This will be directly relevant for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), which seeks to classify more than a million emission-line galaxies into LAEs and low-redshift [O II] emitters. For a simulated HETDEX catalog with realistic measurement noise, the Bayesian method recovers a majority of the LAEs missed by the EW > 20 Angstroms cutoff over 2 < z < 3. The method is robust, performing at least as well as the EW > 20Å cut in contamination (false positives) and incompleteness (false negatives). Trade-off between contamination and incompleteness can be achieved by adjusting the stringency of the probability requirement for classifying an observed object as an LAE. A basic implementation of the Bayesian reduces errors in cosmological parameters by ~22%, which is equivalent to obtaining ~40% more data. The inclusion of the color of the galaxies, contingent on the availability of this information, increases the discriminating power of Bayesian separation and results in further reductions in errors. The Bayesian method is also being used to determine which single broadband filter produces the best performance. This method would enable large-scale structure analyses to be performed directly on emission-line objects labeled with probabilities of being LAEs rather than splitting the sample into LAEs and [O II] emitters.We gratefully acknowledge support from NSF through grant AST-1055919.

  15. Blueberries reduce pro-inflammatory cytokine TNF-alpha and IL-6 production in mouse macrophages by inhibiting NF Kappa B activation and the MAPK pathway

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blueberries (BB) have been reported to attenuate atherosclerosis in apoE deficient (ApoE-/-) mice. The aim of this study was to evaluate the effects of BB in reducing pro-inflammatory cytokine production in mouse macrophages. ApoE-/- mice were fed AIN-93G diet (CD) or CD formulated to contain 1% fre...

  16. Rho iso-alpha acids from hops inhibit the GSK-3/NF-κB pathway and reduce inflammatory markers associated with bone and cartilage degradation

    PubMed Central

    Konda, Veera Reddy; Desai, Anuradha; Darland, Gary; Bland, Jeffrey S; Tripp, Matthew L

    2009-01-01

    Background Rho iso-alpha acids (RIAA) from hops have been shown to have anti-inflammatory properties. To understand the mechanisms, we evaluated the effect of RIAA in cell signaling pathways and inflammatory markers using various in vitro models. We also investigated their therapeutic effect in mice with collagen-induced arthritis. Methods The LPS-stimulated RAW 264.7 macrophages were used to evaluate the effect of RIAA on the NF-κB and MAPK signaling pathways; phosphorylation of ERK1/2, p38 and JNK was assessed by western blotting and NF-κB binding by electrophoretic mobility shift assays. Effect on the NF-κB activity was evaluated by the luciferase reporter assays in LPS-stimulated RAW 264.7 cells. GSK-3α/β kinase activity was measured in cell-free assays. The inhibitory effect of RIAA on inflammatory markers was assessed by measuring nitric oxide in LPS-stimulated RAW 264.7 cells, RANKL-mediated TRAP activity in transformed osteoclasts, and TNF-α/IL-1β-mediated MMP-13 expression in SW1353 cells. Mice with collagen-induced arthritis were fed with RIAA for 2 weeks. Symptoms of joint swelling, arthritic index and joint damage were assessed. Results RIAA selectively inhibited the NF-κB pathway while having no effect on ERK1/2, p38 and JNK phosphorylation in LPS-stimulated RAW 264.7 cells. RIAA also inhibited GSK-3α/β kinase activity and GSK-3β dependent phosphorylation of β-catenin in RAW 264.7 cells. In addition, RIAA inhibited NF-κB-mediated inflammatory markers in various cell models, including nitric oxide in LPS-stimulated RAW 264.7 cells, RANKL-mediated TRAP activity in transformed osteoclasts, and TNF-α/IL-1β-mediated MMP-13 expression in SW1353 human chondrosarcoma cells. Finally, in a mouse model of collagen-induced arthritis, RIAA ameliorated joint damage as evidenced by significant reduction of the arthritis index and histology score; at 250 mg/kg-body weight, RIAA had efficacy similar to that of 20 mg/kg-body weight of celecoxib

  17. Evolution of the alpha particle driven toroidicity induced Alfven mode

    SciTech Connect

    Wu, Y.; White, R.B.; Cheng, C.Z.

    1994-04-01

    The interaction of alpha particles with a toroidicity induced Alfven eigenmode is investigated self-consistently by using a kinetic dispersion relation. All important poloidal harmonics and their radial mode profiles are included. A Hamiltonian guiding center code is used to simulate the alpha particle motion. The simulations include particle orbit width, nonlinear particle dynamics and the effects of the modes on the particles. Modification of the particle distribution leading to mode saturation is observed. There is no significant alpha particle loss.

  18. Alpha Schottky junction energy source

    NASA Astrophysics Data System (ADS)

    Litz, Marc S.; Fan, Zhaoyang; Carroll, James J.; Bayne, Stephen

    2012-06-01

    Isotope batteries offer solutions for long-lived low-power sensor requirements. Alpha emitting isotopes have energy per decay 103 times that of beta emitters. Alpha particles are absorbed within 20 μm of most materials reducing shielding mitigation. However, damage to materials from the alphas limits their practical use. A Schottky Barrier Diode (SBD) geometry is considered with an alpha emitting contact-layer on a diamond-like crystal semiconductor region. The radiation tolerance of diamond, the safety of alpha particles, combined with the internal field of the SBD is expected to generate current useful for low-power electronic devices over decades. Device design parameters and calculations of the expected current are described.

  19. Abdominal surgery reduces the ability of rat spleen cells to synthesize and secrete active tumour necrosis factor-alpha (TNF-α) by a multilevel regulation

    PubMed Central

    Lahat, N; Rahat, M A; Brod, V; Cohen, S; Weber, G; Kinarty, A; Bitterman, H

    1999-01-01

    We have previously shown that abdominal surgery (explorative laparotomy) reduces the ability of lipopolysaccharide (LPS)-triggered spleen macrophages to secrete TNF-α. In this study we characterize possible mechanisms which could be responsible for the reduction in splenic production of TNF-α. Post-operative and control (unoperated) rat splenocytes or enriched splenic macrophages were cultured with LPS. Steady-state levels of TNF-α mRNA were determined by Northern and slot blot analyses, and validated by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). The amount of TNF-α protein was measured by Western blot analysis, and its biological activity was determined by the fibroblast L-929 cytotoxicity assay. Surgery induced a 12-fold inhibition in TNF-α activity (P < 0.02), caused up to two-fold reduction in the accumulation of TNF-α mRNA (P < 0.01), and suppressed TNF-α protein maturation into its 17-kD form in cellular extracts. Post-surgical spleen supernatants revealed mainly a band of a lower molecular weight (14 kD). Our data suggest a multilevel regulation of post-operative inhibition of TNF-α response to LPS, at the accumulation of mRNA, translational and secretory levels. We also suggest that the reduced bioactivity could be partially caused by a proteolytic cleavage of TNF-α. Since TNF-α is an important participant in immune responses, its reduced production and activity may be a central mechanism of post-operative immunosuppression. PMID:9933416

  20. The Stokes line width and uncertainty relations

    NASA Technical Reports Server (NTRS)

    Nikishov, A. I.; Ritus, V. I.

    1994-01-01

    For a function given by contour integral the two types (conventions) of asymptotic representations are considered: the usual representation by asymptotic series in inverse powers of large parameters and the special division of contour integral in contributions of high and low saddle points. It is shown that the width of the recessive term formation zone (Stokes strip) in the second convention is determined by uncertainty relation and is much less than the zone width in the first convention. The reasons of such a difference is clarified. The results of the work are useful for understanding of formation region of the exponentially small process arising on the background of the strong one.

  1. Infrared line widths at planetary atmospheric temperatures

    NASA Technical Reports Server (NTRS)

    Varanasi, Prasad

    1988-01-01

    Recent theoretical models and measurements of the variation of collision-broadened line width with temperature in the infrared are discussed for temperatures relevant to planetary atmospheres. The present review is restricted to lines broadened by H2, N2, O2, CO2, and He, the lines formed in the atmospheres of Jupiter, Saturn, Uranus, and Neptune. The design for a low-temperature absorption cell consisting of a nickel-coated copper tube is described. The lack of an adequate theoretical model for variation of the collision-broadened line width with temperature in terms of the molecular constants of the colliding partners is pointed out.

  2. Anti-Interleukin-1 Beta/Tumor Necrosis Factor-Alpha IgY Antibodies Reduce Pathological Allergic Responses in Guinea Pigs with Allergic Rhinitis

    PubMed Central

    Wei-xu, Hu; Wen-yun, Zhou; Xi-ling, Zhu; Zhu, Wen; Li-hua, Wu; Xiao-mu, Wu; Hui-ping, Wei; Wen-ding, Wang; Dan, He; Qin, Xiang

    2016-01-01

    This study aims to determine whether the combined blockade of IL-1β and TNF-α can alleviate the pathological allergic inflammatory reaction in the nasal mucosa and lung tissues in allergic rhinitis (AR) guinea pigs. Healthy guinea pigs treated with saline were used as the healthy controls. The AR guinea pigs were randomly divided into (1) the AR model group treated with intranasal saline; (2) the 0.1% nonspecific IgY treatment group; (3) the 0.1% anti-TNF-α IgY treatment group; (4) the 0.1% anti-IL-1β IgY treatment group; (5) the 0.1% combined anti-IL-1β and TNF-α IgY treatment group; and (6) the fluticasone propionate treatment group. The inflammatory cells were evaluated using Wright's staining. Histopathology was examined using hematoxylin-eosin staining. The results showed that the number of eosinophils was significantly decreased in the peripheral blood, nasal lavage fluid, and bronchoalveolar lavage fluid (P < 0.05), and eosinophil, neutrophil, and lymphocyte infiltration and edema were significantly reduced or absent in the nasal mucosa and lung tissues (P < 0.05) in the combined 0.1% anti-IL-1β- and TNF-α IgY-treated guinea pigs. The data suggest that topical blockade of IL-1β and TNF-α could reduce pathological allergic inflammation in the nasal mucosa and lung tissues in AR guinea pigs. PMID:27046957

  3. Reduced embryonic survival in rainbow trout resulting from paternal exposure to the environmental estrogen 17 alpha- ethynylestradiol during late sexual maturation

    SciTech Connect

    Brown, Kim H.; Schultz, Irvin R.; Nagler, James J.

    2007-11-01

    Exposure of fishes to environmental estrogens is known to affect sexual development and spawning, but little information exists regarding effects on gametes. This study evaluated embryonic survival of offspring from male rainbow trout (Oncorhynchus mykiss) exposed to 17a-ethynylestradiol (EE2)using an in vitro fertilization protocol. Males were exposed at either 1800 or 6700 degree days (8d) (i.e. 161 or 587 days post-fertilization (dpf)) to test for effects on testes linked to reproductive ontogeny. At 18008d, fish were beginning testicular differentiation and were exposed to 109 ng EE2/l for 21 days. At 67008d, fish have testes containing spermatocytes and spermatids and were exposed for 56 days to either 0.8, 8.3, or 65 ng EE2/l. Semen was collected at full sexual maturity in each group and used to fertilize eggs pooled from several non-exposed females. Significant decreases in embryonic survival were observed only with the 67008d exposure. In 0.8 and 8.3 ng EE2/l treatments, embryo survival was significantly reduced at 19 dpf when compared with the control. In contrast, an immediate decrease in embryonic survival at 0.5 dpf was observed in the 65 ng EE2/l treatment. Blood samples collected at spawning from 67008d exposed males revealed a significant decrease in 11-ketotestosterone and a significant increase in luteinizing hormone levels for the 65 ng EE2/l treatment when compared with the other treatment groups. Results indicate that sexually maturing male rainbow trout are susceptible to EE2 exposure with these fish exhibiting two possible mechanisms of reduced embryonic survival through sperm varying dependant

  4. Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

    SciTech Connect

    Lochter, Andre; Navre, Marc; Werb, Zena; Bissell, Mina J

    1998-06-29

    Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions of integrins during tumor cell invasion.

  5. 7 CFR 29.1085 - Width.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Width. 29.1085 Section 29.1085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... ) (2 ) Waste tolerance (2 ) (2 ) (2 ) 1 Expressed in inches. 2 Expressed in percentage. elements...

  6. 7 CFR 29.1085 - Width.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Width. 29.1085 Section 29.1085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... ) (2 ) Waste tolerance (2 ) (2 ) (2 ) 1 Expressed in inches. 2 Expressed in percentage. elements...

  7. 7 CFR 29.1085 - Width.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Width. 29.1085 Section 29.1085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... ) (2 ) Waste tolerance (2 ) (2 ) (2 ) 1 Expressed in inches. 2 Expressed in percentage. elements...

  8. 7 CFR 29.1085 - Width.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Width. 29.1085 Section 29.1085 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... ) (2 ) Waste tolerance (2 ) (2 ) (2 ) 1 Expressed in inches. 2 Expressed in percentage. elements...

  9. Definition of the {delta} mass and width

    SciTech Connect

    Djukanovic, D.; Scherer, S.; Gegelia, J.

    2007-08-01

    In the framework of effective field theory we show that, at two-loop order, the mass and width of the {delta} resonance defined via the (relativistic) Breit-Wigner parametrization both depend on the choice of field variables. In contrast, the complex-valued position of the pole of the propagator is independent of this choice.

  10. Stability of {sup 248–254}Cf isotopes against alpha and cluster radioactivity

    SciTech Connect

    Santhosh, K.P. Biju, R.K.

    2013-07-15

    Stability of {sup 248–254}Cf nuclei against alpha and cluster emissions is studied within our Coulomb and proximity potential model (CPPM). It is found that these nuclei are stable against light clusters (except alpha particles) and unstable against heavy cluster (A{sub 2}≥40) emissions. For heavy cluster emissions the daughter nuclei lead to doubly magic {sup 208}Pb or the neighbouring one. The effects of quadrupole and hexadecapole deformations of parent nuclei, daughter nuclei and emitted cluster on half lives are also studied. The computed alpha decay half life values (including quadrupole deformation β{sub 2}) are in close agreement with experimental data. Inclusion of quadrupole deformation reduces the height and width of the barrier (increases the barrier penetrability) and hence half life decreases. -- Highlights: •{sup 248–254}Cf parents are stable against light clusters (except alpha particles) and are unstable against heavy clusters ({sup 46}Ar, {sup 48,50}Ca etc.). •For the case of heavy cluster emissions the daughter nuclei are doubly magic {sup 208}Pb or neighbouring one. •The alpha decay half lives are in agreement with experimental data. •The cluster decay half lives decrease with the inclusion of quadrupole deformation.

  11. Inflammatory activation is associated with a reduced glucocorticoid receptor alpha/beta expression ratio in monocytes of inpatients with melancholic major depressive disorder

    PubMed Central

    Carvalho, L A; Bergink, V; Sumaski, L; Wijkhuijs, J; Hoogendijk, W J; Birkenhager, T K; Drexhage, H A

    2014-01-01

    In this study, we used new technology to investigate whether a coherent pattern of enhanced expression of inflammatory and other immune activation genes in circulating monocytes is found in patients with major depression. Since a high inflammatory state of monocytes might be related to glucocorticoid resistance, we also included the genes for the two isoforms of the glucocorticoid receptor. For this study, we aimed at finding a similar coherent pattern of inflammatory and immune activation genes in monocytes of patients with MDD and recruited 47 medication-free melancholic MDD inpatients and 42 healthy controls. A quantitative-polymerase chain reaction (Q-PCR) monocyte gene expression analysis was performed using a panel of inflammatory-related genes previously identified as abnormally regulated in mood disorder patients. Selected serum cytokines/chemokines were assessed using a cytometric bead array. Depressive symptoms were analysed using Hamilton depression scores (HAMD). Thirty-four of the 47 monocyte inflammatory-related genes were significantly upregulated and 2 were significantly downregulated as compared to controls, the latter including the gene for the active GRα in particular in those with a high HAMD score. The reduced GRα expression correlated strongly to the upregulation of the inflammatory genes in monocytes. Serum levels of IL6, IL8, CCL2 and VEGF were significantly increased in patients compared to controls. Our data show the deregulation of two interrelated homoeostatic systems, that is, the immune system and the glucocorticoid system, co-occurring in major depression. PMID:24424390

  12. Measurement of giant dipole resonance width at low temperature: A new experimental perspective

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, S.; Pandit, Deepak; Pal, Surajit; Bhattacharya, Srijit; De, A.; Bhattacharya, S.; Bhattacharya, C.; Banerjee, K.; Kundu, S.; Rana, T. K.; Mukherjee, G.; Pandey, R.; Gohil, M.; Pai, H.; Meena, J. K.; Banerjee, S. R.

    2012-03-01

    The systematic evolution of the giant dipole resonance (GDR) width in the temperature region of 0.9- 1.4 MeV has been measured experimentally for 119Sb using alpha induced fusion reaction and employing the LAMBDA high energy photon spectrometer. The temperatures have been precisely determined by simultaneously extracting the vital level density parameter from the neutron evaporation spectrum and the angular momentum from gamma multiplicity filter using a realistic approach. The systematic trend of the data seems to disagree with the thermal shape fluctuation model (TSFM). The model predicts the gradual increase of GDR width from its ground state value whereas the measured GDR widths appear to remain constant at the ground state value till T ∼ 1 MeV and increase thereafter, indicating towards a failure of the adiabatic assumption of the model at low temperature.

  13. Three mutations identified in the voltage-sensitive sodium channel alpha-subunit gene of permethrin-resistant human head lice reduce the permethrin sensitivity of house fly Vssc1 sodium channels expressed in Xenopus oocytes.

    PubMed

    SupYoon, Kyong; Symington, Steven B; Hyeock Lee, Si; Soderlund, David M; Marshall Clark, J

    2008-03-01

    Point mutations in the para-orthologous sodium channel alpha-subunit of the head louse (M815I, T917I, and L920F) are associated with permethrin resistance and DDT resistance. These mutations were inserted in all combinations using site-directed mutagenesis at the corresponding amino acid sequence positions (M827I, T929I, and L932F) of the house fly para-orthologous voltage-sensitive sodium channel alpha-subunit (Vssc1(WT)) gene and heterologously co-expressed with the sodium channel auxiliary subunit of house fly (Vsscbeta) in Xenopus oocytes. The double mutant possessing M827I and T929I (Vssc1(MITI)/Vsscbeta) caused a approximately 4.0mV hyperpolarizing shift and the triple mutant, Vssc1(MITILF)/Vsscbeta, caused a approximately 3.2mV depolarizing shift in the voltage dependence of activation curves. Vssc1(MITI)/Vsscbeta, Vssc1(TILF)/Vsscbeta, and Vssc1(MITILF)/Vsscbeta caused depolarizing shifts ( approximately 6.6, approximately 7.6, and approximately 8.8mV, respectively) in the voltage dependence of steady-state inactivation curves. The M827I and L932F mutations reduced permethrin sensitivity when expressed alone but the T929I mutation, either alone or in combination, virtually abolished permethrin sensitivity. Thus, the T929I mutation is the principal cause of permethrin resistance in head lice. Comparison of the expression rates of channels containing single, double and triple mutations with that of Vssc1(WT)/Vsscbeta channels indicates that the M827I mutation may play a role in rescuing the decreased expression of channels containing T929I. PMID:18252244

  14. Poly(I:C) reduces expression of JAM-A and induces secretion of IL-8 and TNF-{alpha} via distinct NF-{kappa}B pathways in human nasal epithelial cells

    SciTech Connect

    Ohkuni, Tsuyoshi; Kojima, Takashi; Ogasawara, Noriko; Masaki, Tomoyuki; Fuchimoto, Jun; Kamekura, Ryuta; Koizumi, Jun-ichi; Ichimiya, Shingo; Murata, Masaki; Tanaka, Satoshi; Himi, Tetsuo; Sawada, Norimasa

    2011-01-01

    Human nasal epithelium is an important physical barrier and innate immune defense protecting against inhaled substances and pathogens. Toll-like receptor (TLR) signaling, which plays a key role in the innate immune response, has not been well characterized in human nasal epithelial cells (HNECs), including the epithelial tight junctional barrier. In the present study, mRNAs of TLR1-10 were detected in hTERT-transfected HNECs, which can be used as an indispensable and stable model of normal HNECs, similar to primary cultured HNECs. To investigate the changes of tight junction proteins and the signal transduction pathways via TLRs in HNECs in vitro, hTERT-transfected HNECs were treated with TLR2 ligand P{sub 3}CSK{sub 4}, TLR3 ligand poly(I:C), TLR4 ligand LPS, TLR7/8 ligand CL097, TLR8 ligand ssRNA40/LyoVec, and TLR9 ligand ODN2006. In hTERT-transfected HNECs, treatment with poly(I:C) significantly reduced expression of the tight junction protein JAM-A and induced secretion of proinflammatory cytokines IL-8 and TNF-{alpha}. Both the reduction of JAM-A expression and the induction of secretion of IL-8 and TNF-{alpha} after treatment with poly(I:C) were modulated by distinct signal transduction pathways via EGFR, PI3K, and p38 MAPK and finally regulated by a TLR3-mediated NF-{kappa}B pathway. The control of TLR3-mediated signaling pathways in HNECs may be important not only in infection by viral dsRNA but also in autoimmune diseases caused by endogenous dsRNA released from necrotic cells.

  15. Phase envelopes for variable width square well chain fluids

    NASA Astrophysics Data System (ADS)

    Cui, Jingyu; Elliott, J. Richard

    2001-04-01

    Discontinuous Molecular Dynamics (DMD) and Thermodynamic Perturbation Theory (TPT) have been used to study square-well (SW) chain molecules with variable well-width SW potentials. Well widths of 1.5, 1.8, and 2.0 are considered for united atom models of ethane, n-hexane, and n-octane. The properties studied are the acentric factor, vapor pressure, and liquid density. DMD of purely repulsive potentials was applied to record the number of interaction sites in different wells, giving estimates of the TPT contributions from the attractive potential. DMD simulations of the complete potential near the coexistence condition were used to refine estimates of the derivative quantities related to the compressibility factor. Evaluations of this approach indicate that it is accurate and efficient at βɛ>0 and η>0.28. Phase diagrams of pure fluids also indicate quantitative accuracy for DMD/TPT at reduced temperatures less than 0.9. The results show that wider wells improve the representation of thermodynamic properties for longer chains. The well width becomes a function of the molecular weight, however.

  16. Effects of pacing magnitudes and forms on bistability width in a modeled ventricular tissue

    NASA Astrophysics Data System (ADS)

    Huang, Xiaodong; Liu, Xuemei; Zheng, Lixian; Mi, Yuanyuan; Qian, Yu

    2013-07-01

    Bistability in periodically paced cardiac tissue is relevant to cardiac arrhythmias and its control. In the present paper, one-dimensional tissue of the phase I Luo-Rudy model is numerically investigated. The effects of various parameters of pacing signals on bistability width are studied. The following conclusions are obtained: (i) Pacing can be classified into two types: pulsatile and sinusoidal types. Pulsatile pacing reduces bistability width as its magnitude is increased. Sinusoidal pacing increases the width as its amplitude is increased. (ii) In a pacing period the hyperpolarizing part plays a more important role than the depolarizing part. Variations of the hyperpolarizing ratio in a period evidently change the width of bistability and its variation tendency. (iii) A dynamical mechanism is proposed to qualitatively explain the phenomena, which reveals the reason for the different effects of pulsatile and sinusoidal pacing on bistability. The methods for changing bistability width by external pacing may help control arrhythmias in cardiology.

  17. Are There Any Good Digraph Width Measures?

    NASA Astrophysics Data System (ADS)

    Ganian, Robert; Hliněný, Petr; Kneis, Joachim; Meister, Daniel; Obdržálek, Jan; Rossmanith, Peter; Sikdar, Somnath

    Several width measures for digraphs have been proposed in the last few years. However, none of them possess all the "nice" properties of treewidth, namely, (1) being algorithmically useful, that is, admitting polynomial-time algorithms for a large class of problems on digraphs of bounded width; and (2) having nice structural properties such as being monotone under taking subdigraphs and some form of arc contractions. As for (1), MSO1 is the least common denominator of all reasonably expressive logical languages that can speak about the edge/arc relation on the vertex set, and so it is quite natural to demand efficient solvability of all MSO1-definable problems in this context. (2) is a necessary condition for a width measure to be characterizable by some version of the cops-and-robber game characterizing treewidth. More specifically, we introduce a notion of a directed topological minor and argue that it is the weakest useful notion of minors for digraphs in this context. Our main result states that any reasonable digraph measure that is algorithmically useful and structurally nice cannot be substantially different from the treewidth of the underlying undirected graph.

  18. Alpha-1 Antitrypsin Deficiency

    MedlinePlus

    ... from the NHLBI on Twitter. What Is Alpha-1 Antitrypsin Deficiency? Alpha-1 antitrypsin (an-tee-TRIP-sin) deficiency, or AAT ... as it relates to lung disease. Overview Alpha-1 antitrypsin, also called AAT, is a protein made ...

  19. Microtubule depolymerization potentiates alpha-synuclein oligomerization.

    PubMed

    Esteves, A Raquel; Arduíno, Daniela M; Swerdlow, Russell H; Oliveira, Catarina R; Cardoso, Sandra M

    2010-01-01

    Parkinson's disease (PD) is associated with perturbed mitochondria function and alpha-synuclein fibrillization. We evaluated potential mechanistic links between mitochondrial dysfunction and alpha-synuclein aggregation. We studied a PD cytoplasmic hybrid (cybrid) cell line in which platelet mitochondria from a PD subject were transferred to NT2 neuronal cells previously depleted of endogenous mitochondrial DNA. Compared to a control cybrid cell line, the PD line showed reduced ATP levels, an increased free/polymerized tubulin ratio, and alpha-synuclein oligomer accumulation. Taxol (which stabilizes microtubules) normalized the PD tubulin ratio and reduced alpha-synuclein oligomerization. A nexus exists between mitochondrial function, cytoskeleton homeostasis, and alpha-synuclein oligomerization. In our model, mitochondrial dysfunction triggers an increased free tubulin, which destabilizes the microtubular network and promotes alpha-synuclein oligomerization. PMID:20552056

  20. Chicken interferon alpha pretreatment reduces virus replication of pandemic H1N1 and H5N9 avian influenza viruses in lung cell cultures from different avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Type I interferons, including interferon (IFN)-alpha, represent one of the first lines of innate immune defense against influenza virus infection. Following natural infection of chickens with avian influenza virus (AIV), transcription of IFN-alpha is quickly up regulated along with multiple other im...

  1. Artifacts for Calibration of Submicron Width Measurements

    NASA Technical Reports Server (NTRS)

    Grunthaner, Frank; Grunthaner, Paula; Bryson, Charles, III

    2003-01-01

    Artifacts that are fabricated with the help of molecular-beam epitaxy (MBE) are undergoing development for use as dimensional calibration standards with submicron widths. Such standards are needed for calibrating instruments (principally, scanning electron microscopes and scanning probe microscopes) for measuring the widths of features in advanced integrated circuits. Dimensional calibration standards fabricated by an older process that involves lithography and etching of trenches in (110) surfaces of single-crystal silicon are generally reproducible to within dimensional tolerances of about 15 nm. It is anticipated that when the artifacts of the present type are fully developed, their critical dimensions will be reproducible to within 1 nm. These artifacts are expected to find increasing use in the semiconductor-device and integrated- circuit industries as the width tolerances on semiconductor devices shrink to a few nanometers during the next few years. Unlike in the older process, one does not rely on lithography and etching to define the critical dimensions. Instead, one relies on the inherent smoothness and flatness of MBE layers deposited under controlled conditions and defines the critical dimensions as the thicknesses of such layers. An artifact of the present type is fabricated in two stages (see figure): In the first stage, a multilayer epitaxial wafer is grown on a very flat substrate. In the second stage, the wafer is cleaved to expose the layers, then the exposed layers are differentially etched (taking advantage of large differences between the etch rates of the different epitaxial layer materials). The resulting structure includes narrow and well-defined trenches and a shelf with thicknesses determined by the thicknesses of the epitaxial layers from which they were etched. Eventually, it should be possible to add a third fabrication stage in which durable, electronically inert artifacts could be replicated in diamondlike carbon from a master made by

  2. Beta/alpha continuous air monitor

    DOEpatents

    Becker, Gregory K.; Martz, Dowell E.

    1989-01-01

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinguishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts.

  3. Beta/alpha continuous air monitor

    DOEpatents

    Becker, G.K.; Martz, D.E.

    1988-06-27

    A single deep layer silicon detector in combination with a microcomputer, recording both alpha and beta activity and the energy of each pulse, distinquishing energy peaks using a novel curve fitting technique to reduce the natural alpha counts in the energy region where plutonium and other transuranic alpha emitters are present, and using a novel algorithm to strip out radon daughter contribution to actual beta counts. 7 figs.

  4. GAS MOTION STUDY OF Ly{alpha} EMITTERS AT z {approx} 2 USING FUV AND OPTICAL SPECTRAL LINES {sup ,}

    SciTech Connect

    Hashimoto, Takuya; Shimasaku, Kazuhiro; Nakajima, Kimihiko; Ouchi, Masami; Ono, Yoshiaki; Rauch, Michael; Janice Lee; Okamura, Sadanori

    2013-03-01

    We present the results of Magellan/MMIRS and Keck/NIRSPEC spectroscopy for five Ly{alpha} emitters (LAEs) at z {approx_equal} 2.2 for which high-resolution FUV spectra from Magellan/MagE are available. We detect nebular emission lines including H{alpha} on the individual basis and low-ionization interstellar (LIS) absorption lines in a stacked FUV spectrum, and measure average offset velocities of the Ly{alpha} line, {Delta}v {sub Ly{alpha}}, and LIS absorption lines, {Delta}v {sub abs}, with respect to the systemic velocity defined by the nebular lines. For a sample of eight z {approx} 2-3 LAEs without active galactic nucleus from our study and the literature, we obtain {Delta}v {sub Ly{alpha}} = 175 {+-} 35 km s{sup -1}, which is significantly smaller than that of Lyman-break Galaxies (LBGs), {Delta}v {sub Ly{alpha}} {approx_equal} 400 km s{sup -1}. The stacked FUV spectrum gives {Delta}v {sub abs} = -179 {+-} 73 km s{sup -1}, comparable to that of LBGs. These positive {Delta}v {sub Ly{alpha}} and negative {Delta}v {sub abs} suggest that LAEs also have outflows. In contrast to LBGs, however, the LAEs' {Delta}v {sub Ly{alpha}} is as small as |{Delta}v {sub abs}|, suggesting low neutral hydrogen column densities. Such a low column density with a small number of resonant scattering may cause the observed strong Ly{alpha} emission of LAEs. We find an anti-correlation between Ly{alpha} equivalent width (EW) and {Delta}v {sub Ly{alpha}} in a compilation of LAE and LBG samples. Although its physical origin is not clear, this anti-correlation result appears to challenge the hypothesis that a strong outflow, by means of a reduced number of resonant scattering, produces a large EW. If LAEs at z > 6 have similarly small {Delta}v {sub Ly{alpha}} values, constraints on the reionization history derived from the Ly{alpha} transmissivity may need to be revised.

  5. Antibody-mediated reduction of .alpha.-ketoamides

    DOEpatents

    Schultz, Peter G.; Gallop, Mark A.

    1998-01-01

    Monoclonal antibodies raised against a 4-nitrophenyl phosphonate hapten catalyze the stereospecific reduction of an .alpha.-ketoamide to the corresponding .alpha.-hydroxyamide in the presence of an appropriate reducing agent.

  6. Antibody-mediated reduction of {alpha}-ketoamides

    DOEpatents

    Schultz, P.G.; Gallop, M.A.

    1998-06-09

    Monoclonal antibodies raised against a 4-nitrophenyl phosphonate hapten catalyze the stereospecific reduction of an {alpha}-ketoamide to the corresponding {alpha}-hydroxyamide in the presence of an appropriate reducing agent.

  7. Adalimumab (tumor necrosis factor-blocker) reduces the expression of glial fibrillary acidic protein immunoreactivity increased by exogenous tumor necrosis factor alpha in an organotypic culture of porcine neuroretina

    PubMed Central

    Garcia-Gutierrez, M.T.; Srivastava, G.K.; Gayoso, M.J.; Gonzalo-Orden, J.M.; Pastor, J.C.

    2013-01-01

    Purpose To determine if exogenous addition of tumor necrosis factor alpha (TNFα) exacerbates retinal reactive gliosis in an organotypic culture of porcine neuroretina and to evaluate if concomitant adalimumab, a TNF-blocker, diminishes it. Methods Porcine retinal explants from 20 eyeballs were cultured. Cultures with 100 pg/ml TNFα, 10 µg/ml adalimumab, 100 pg/ml TNFα plus 10 µg/ml adalimumab, or controls without additives were maintained for 9 days. Freshly detached retinas were processed in parallel. TNFα levels in control culture supernatants were quantified with enzyme-linked immunosorbent assay. Cryostat sections were doubly immunostained for glial fibrillary acidic protein (GFAP), a marker for reactive gliosis, and cellular retinaldehyde-binding protein (CRALBP), a marker for Müller cells. Sections were also labeled with the isolectin IB4, a label for microglia/macrophages. Results TNFα in control culture supernatants was detected only at day 1. Compared to the fresh neuroretinal samples, upregulation of GFAP and downregulation of CRALBP occurred during the 9 days of culture. Exogenous TNFα stimulated glial cells to upregulate GFAP and downregulate CRALBP immunoreactivity. TNFα-treated cultures also initiated the growth of gliotic membranes and underwent retinal disorganization. Adalimumab inhibited the spontaneous increases in GFAP and maintained CRALBP. In combination with TNFα, adalimumab reduced GFAP expression and conserved CRALBP, with only slight retinal disorganization. No appreciable changes in IB4 labeling were observed under the different culture conditions. Conclusions In cultured porcine neuroretina, spontaneous reactive gliosis and retinal disorganization were exacerbated by exogenous TNFα. Adalimumab reduced spontaneous changes and those induced by TNFα. Therefore, inhibiting TNFα may represent a novel approach to controlling retinal fibrosis observed in some human diseases. PMID:23687426

  8. Pulse width modulation inverter with battery charger

    NASA Technical Reports Server (NTRS)

    Slicker, James M. (Inventor)

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a flyback DC-DC converter circuit for recharging the battery.

  9. Optical antennas with sinusoidal modulation in width.

    PubMed

    Dikken, Dirk Jan; Segerink, Frans B; Korterik, Jeroen P; Pfaff, Stefan S; Prangsma, Jord C; Herek, Jennifer L

    2016-08-01

    Small metal structures sustaining plasmon resonances in the optical regime are of great interest due to their large scattering cross sections and ability to concentrate light to subwavelength volumes. In this paper, we study the dipolar plasmon resonances of optical antennas with a constant volume and a sinusoidal modulation in width. We experimentally show that by changing the phase of the width-modulation, with a small 10 nm modulation amplitude, the resonance shifts over 160 nm. Using simulations we show how this simple design can create resonance shifts greater than 600 nm. The versatility of this design is further shown by creating asymmetric structures with two different modulation amplitudes, which we experimentally and numerically show to give rise to two resonances. Our results on both the symmetric and asymmetric antennas show the capability to control the localization of the fields outside the antenna, while still maintaining the freedom to change the antenna resonance wavelength. The antenna design we tested combines a large spectral tunability with a small footprint: all the antenna dimensions are factor 7 to 13 smaller than the wavelength, and hold potential as a design element in meta-surfaces for beam shaping. PMID:27505755

  10. Pulse width modulation inverter with battery charger

    DOEpatents

    Slicker, James M.

    1985-01-01

    An inverter is connected between a source of DC power and a three-phase AC induction motor, and a microprocessor-based circuit controls the inverter using pulse width modulation techniques. In the disclosed method of pulse width modulation, both edges of each pulse of a carrier pulse train are equally modulated by a time proportional to sin .theta., where .theta. is the angular displacement of the pulse center at the motor stator frequency from a fixed reference point on the carrier waveform. The carrier waveform frequency is a multiple of the motor stator frequency. The modulated pulse train is then applied to each of the motor phase inputs with respective phase shifts of 120.degree. at the stator frequency. Switching control commands for electronic switches in the inverter are stored in a random access memory (RAM) and the locations of the RAM are successively read out in a cyclic manner, each bit of a given RAM location controlling a respective phase input of the motor. The DC power source preferably comprises rechargeable batteries and all but one of the electronic switches in the inverter can be disabled, the remaining electronic switch being part of a "flyback" DC-DC converter circuit for recharging the battery.

  11. Investigating Starburst Galaxy Emission Line Equivalent Widths

    NASA Astrophysics Data System (ADS)

    Meskhidze, Helen; Richardson, Chris T.

    2016-01-01

    Modeling star forming galaxies with spectral synthesis codes allows us to study the gas conditions and excitation mechanisms that are necessary to reproduce high ionization emission lines in both local and high-z galaxies. Our study uses the locally optimally-emitting clouds model to develop an atlas of starburst galaxy emission line equivalent widths. Specifically, we address the following question: What physical conditions are necessary to produce strong high ionization emission lines assuming photoionization via starlight? Here we present the results of our photoionization simulations: an atlas spanning 15 orders of magnitude in ionizing flux and 10 orders of magnitude in hydrogen density that tracks over 150 emission lines ranging from the UV to the near IR. Each simulation grid contains ~1.5x104 photoionization models calculated by supplying a spectral energy distribution, grain content, and chemical abundances. Specifically, we will be discussing the effects on the emission line equivalent widths of varying the metallicity of the cloud, Z = 0.2 Z⊙ to Z = 5.0 Z⊙, and varying the star-formation history, using the instantaneous and continuous evolution tracks and the newly released Starburst99 Geneva rotation tracks.

  12. Lyman Alpha Emitting Galaxies at 2 < z < 3: Towards a Calibrated Probe of Dark Energy

    SciTech Connect

    Caryl Gronwall

    2012-12-03

    The goal of this project was to establish the physical properties of Ly{alpha} emitting galaxies from redshifts of 2 to 3 in order to better calibrate the use of LAEs as probes of the large scale structure of the universe for upcoming dark energy experiments, such as the Hobby Eberly Telescope Dark Energy Experiment (HETDEX). We have obtained narrow-band imaging of the Extended Chandra Deep Field South (ECDF-S) in two different narrow-band filters centered at Ly{alpha} at z=2.1 and 3.1. The resulting of samples of LAEs were used to determine the LAE luminosity function, equivalent width distribution and clustering properties (bias) of LAEs at these redshifts. While the results from the ECDF-S appear robust, they are based on a single field. To explore the effects of cosmic variance and galaxy environment on the physical properties of LAEs, we have also obtained narrow-band data at both redshifts (z = 2:1 and 3:1) in three additional fields (SDSS 1030+-05, the Extended Hubble Deep Field South, and CW 1255+01). The narrow-band imaging data has been reduced and LAE catalogs are being generated. We have calculated preliminary luminosity functions, equivalent width distributions, and clustering properties. We have also obtained follow-up spectroscopy in the optical (using VLT/FORS) and in the near-infrared (using Magellan/MMIRS). Since individual LAEs have too little S/N to enable meaningful fits for stellar population parameters, our previous work has analyzed stacked Spectral Energy Distributions (SEDs). SED fitting was performed on several subsets of LAEs selected by their rest-UV luminosity, UV spectral slope, Ly alpha luminosity, Equivalent Width, or rest-optical (IRAC) luminosity.

  13. Search for rapid H-alpha variability studies in Be stars - 28 Eri, X Ophiuchi, 66 Ophiuchi and Pi Aquarii

    NASA Astrophysics Data System (ADS)

    Ghosh, K. K.

    1988-10-01

    In order to search for rapid H&alpha; variability in Be stars, a series of H&alpha; profiles were observed on a time scale of few minutes for 28 Eri, X Oph, 66 Oph and π Aqr. In total, 95 and 54 H&alpha; profiles were obtained for the program Be stars and the standard stars respectively. The theoretical expression of Chalabaev and Maillard (1983) was used to estimate the uncertainty of the H&alpha; equivalent width measurements. It is found that rapid variations of continuum level and equivalent widths of H&alpha; line are absent.

  14. Solar-Cycle Changes in GONG P-Mode Widths and Amplitudes 1995-1998

    NASA Technical Reports Server (NTRS)

    Komm R. W.; Howe, R.; Hill, F.

    1999-01-01

    We search for a solar cycle variation in mode widths and amplitudes derived from 3-month GONG time series. The variation of mode width and amplitude observed in GONG data are the combined effects of fill factor, temporal variation, and measurement uncertainties. The largest variation is caused by the fill factor resulting in modes with increased width and reduced amplitude when fill is lower. We assume that the solar cycle variation is the only other systematic variation beside the temporal window function effect. We correct all currently available data sets for the fill factor and simultaneously derive the solar cycle variation. We find an increase of about 3% on average in mode width from the previous minimum to Oct. 1998 and a decrease of about 7% and 6% in mode amplitude and mode area (width x amplitude). We find no l dependence of the solar-cycle changes. As a function of frequency, these changes show a maximum between 2.7 and 3.3 mHz with about 47% higher than average values for mode width and about 29% and 36% higher ones for mode amplitude and area. We estimate the significance of these rather small changes by a pre-whitening method and find that the results are significant at or above the 99.9% level with mode area showing the highest level of significance and mode width the lowest. The variation in background amplitude is most likely not significant and is consistent with a zero change.

  15. Replacement of Lys Linker with Arg Linker Resulting in Improved Melanoma Uptake and Reduced Renal Uptake of Tc-99m-Labeled Arg-Gly-Asp-Conjugated Alpha-Melanocyte Stimulating Hormone Hybrid Peptide

    PubMed Central

    Yang, Jianquan; Guo, Haixun; Padilla, R. Steve; Berwick, Marianne; Miao, Yubin

    2010-01-01

    The purpose of this study was to reduce the non-specific renal uptake of Arg-Gly-Asp (RGD)-conjugated alpha-melanocyte stimulating hormone (α-MSH) hybrid peptide through structural modification or L-lysine co-injection. The RGD motif {cyclic(Arg-Gly-Asp-dTyr-Asp)} was coupled to [Cys3,4,10, d-Phe7, Arg11]α-MSH3-13 {(Arg11)CCMSH} through the Arg linker (substituting the Lys linker) to generate a novel RGD-Arg-(Arg11)CCMSH hybrid peptide. The melanoma targeting and pharmacokinetic properties of 99mTc-RGD-Arg-(Arg11)CCMSH were determined in B16/F1 melanoma-bearing C57 mice. The effect of L-lysine co-injection on the renal uptake was determined through the co-injection of L-lysine with 99mTc-RGD-Arg-(Arg11)CCMSH or 99mTc-RGD-Lys-(Arg11)CCMSH. Replacement of the Lys linker with an Arg linker exhibited a profound effect in reducing the non-specific renal uptake of 99mTc-RGD-Arg-(Arg11)CCMSH, as well as increasing the tumor uptake of 99mTc-RGD-Arg-(Arg11)CCMSH compared to 99mTc-RGD-Lys-(Arg11)CCMSH. 99mTc-RGD-Arg-(Arg11)CCMSH exhibited high tumor uptake (21.41 ± 3.74% ID/g at 2 h post-injection) and prolonged tumor retention (6.81 ± 3.71% ID/g at 24 h post-injection) in B16/F1 melanoma-bearing mice. The renal uptake values of 99mTc-RGD-Arg-(Arg11)CCMSH were 40.14-64.08% of those of 99mTc-RGD-Lys-(Arg11)CCMSH (p<0.05) at 0.5, 2, 4 and 24 h post-injection. Co-injection of L-lysine was effective in decreasing the renal uptakes of 99mTc-RGD-Arg-(Arg11)CCMSH by 27.7% and 99mTc-RGD-Lys-(Arg11)CCMSH by 52.1% at 2 h post-injection. Substitution of the Lys linker with an Arg linker dramatically improved the melanoma uptake and reduced the renal uptake of 99mTc-RGD-Arg-(Arg11)CCMSH, warranting the further evaluation of 188Re-labeled RGD-Arg-(Arg11)CCMSH as a novel MC1 receptor-targeting therapeutic peptide for melanoma treatment in the future. PMID:20728365

  16. Direct measurement of the W boson width

    SciTech Connect

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Aguilo, E.; Ahsan, M.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; /Michigan U. /Northeastern U.

    2009-09-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

  17. Quantum Monte Carlo calculations of neutron-alpha scattering.

    SciTech Connect

    Nollett, K. M.; Pieper, S. C.; Wiringa, R. B.; Carlson, J.; Hale, G. M.; Physics

    2007-07-13

    We describe a new method to treat low-energy scattering problems in few-nucleon systems, and we apply it to the five-body case of neutron-alpha scattering. The method allows precise calculations of low-lying resonances and their widths. We find that a good three-nucleon interaction is crucial to obtain an accurate description of neutron-alpha scattering.

  18. Quantum Monte Carlo Calculations of Neutron-{alpha} Scattering

    SciTech Connect

    Nollett, Kenneth M.; Pieper, Steven C.; Wiringa, R. B.; Carlson, J.; Hale, G. M.

    2007-07-13

    We describe a new method to treat low-energy scattering problems in few-nucleon systems, and we apply it to the five-body case of neutron-alpha scattering. The method allows precise calculations of low-lying resonances and their widths. We find that a good three-nucleon interaction is crucial to obtain an accurate description of neutron-alpha scattering.

  19. Alpha-decay properties of /sup 205-208/Fr: Identification of /sup 206/Fr/sup m/

    SciTech Connect

    Ritchie, B.G.; Toth, K.S.; Carter, H.K.; Mlekodaj, R.L.; Spejewski, E.H.

    1981-05-01

    Alpha-particle and ..gamma..-ray spectral measurements were made for /sup 205-208/Fr. A new a emitter (T/sub 1/2/ = 0.7 +- 0.1 sec and E/sub a/ = 6.930 +- 0.005 MeV) was observed and identified with the decay of a previously unknown isomer in /sup 206/Fr. From the a particle and g ray intensities, a decay branching ratios were deduced for /sup 205-208/Fr utilizing available information concerning the nuclides' (electron capture+positron) decay properties. Reduced widths were calculated and compared with those of neighboring nuclei.

  20. Neutron decay widths of excited states of {sup 11}Be

    SciTech Connect

    Haigh, P. J.; Freer, M.; Ashwood, N. I.; Bloxham, T.; Curtis, N.; McEwan, P.; Bohlen, H. G.; Dorsch, T.; Kokalova, Tz.; Schulz, Ch.; Wheldon, C.

    2009-01-15

    The two-neutron transfer reaction {sup 9}Be({sup 16}O, {sup 14}O){sup 11}Be[{sup 10}Be +n] has been used to measure the branching ratios for the neutron decay of excited states of {sup 11}Be. The {sup 14}O ejectile was detected by a Q3D spectrometer at forward angles. The energies and angles of the {sup 10}Be fragments of the decaying {sup 11}Be* recoil were measured in coincidence with the {sup 14}O ejectile using a double-sided silicon strip detector array at backward angles. This enabled a kinematic reconstruction of the reaction to be performed. Theoretical decay branch ratios were calculated using barrier penetrability factors and were compared to the measured ratios to provide information on the relative reduced widths of the states. The decay widths have been used to link states in {sup 11}Be with a common structure and structurally to states in the daughter nucleus {sup 10}Be. The 3/2{sup -} 8.82-MeV state was identified as a candidate for a molecular band head.

  1. Pulse-width-independent low power programmable low temperature poly-Si thin-film transistor shift register

    NASA Astrophysics Data System (ADS)

    Song, Eunji; Song, Seok-Jeong; Nam, Hyoungsik

    2015-05-01

    This paper demonstrates a low power programmable pulse width LTPS TFT shift register which achieves the constant power consumption over various pulse widths with the smaller number of TFTs compared to the previous programmable shift register. The proposed shift register consists of nine n-channel LTPS TFTs and one coupling capacitor. By eliminating the shoot-through current path in a NOT-AND logic, the simulation ensures that the proposed structure reduces the power consumption significantly by 60.5% for two line pulse width and by 88.6% for ten line pulse width from the previous programmable pulse width shift register. The power consumption of 12 shift registers is measured at 0.235 mW, independently of programmed pulse widths.

  2. Real time pulse width monitor for Intensified Charge Coupled Device (ICCD) electro-optic shutters

    SciTech Connect

    Yates, G.J.

    1996-12-01

    A method is described or controlling and measuring the pulse width of electrical gate pulses used for optical shuttering of image intensifier. The intensifiers are coupled to high frame rate Charge-Coupled-Devices (CCD) or Focus-Projection Scan (FPS) vidicon TV cameras for readout and telemetry of time resolved image sequences. The shutter duration or gate width of individual shutters is measured in real time and encoded in the video frame corresponding to a given shutter interval. The shutter information is updated once catch video frame by strobing new data with each TV camera vertical sync pulse. This circuitry is used in conjunction with commercial video insertion/annotation equipment to provide die shutter width information in alpha numeric text form along with the time resolved video image on a frame-by-frame basis. The measurement technique and circuitry involving a combination of high speed digital counters and analog integrators for measurements in the Ins to 1024 ns range are described. The accuracy obtained is compared with measurements obtained using batch speed DSOs. The measured data are provided in 10-bit Binary (Bi) and four decades of Binary Coded Decimal (BCD) and also displayed on four digit seven segment displays. The control circuitry including digital and analog input means for gate width selection are described. The implementation of both measurement and control circuitry into an Intensified Shuttered CCD (ISCCD) radiometric system for recording fast shuttered images at RS-170 to 4 KHz frame rates is presented.

  3. Circuit multiplies pulse width modulation, exhibits linear transfer function

    NASA Technical Reports Server (NTRS)

    Carlson, A. W.; Furciniti, A.

    1967-01-01

    Modulation multiplier provides a simple means of multiplying the width modulation of a pulse train by a constant factor. It operates directly on a pulse width modulated input signal to generate an output pulse train having a greater degree of width modulation than the input signal.

  4. Effect of EDTA on the metastable zone width of ADP

    NASA Astrophysics Data System (ADS)

    Rajesh, N. P.; Meera, K.; Srinivasan, K.; Santhana Raghavan, P.; Ramasamy, P.

    2000-06-01

    Enhancement of the metastable zone width in ammonium dihydrogen ortho phosphate (ADP) was achieved by the addition of 1 mol% of the chelating agent ethylenediaminetetra acetic acid (EDTA) to ADP solution. The metastable zone width studies were conducted and the nucleation parameters were calculated from the measurements of the dependence of the metastable zone width on the cooling rate.

  5. ENERGY-DEPENDENT GAMMA-RAY BURST PULSE WIDTH DUE TO THE CURVATURE EFFECT AND INTRINSIC BAND SPECTRUM

    SciTech Connect

    Peng, Z. Y.; Ma, L.; Zhao, X. H.; Yin, Y.; Bao, Y. Y.

    2012-06-20

    Previous studies have found that the width of the gamma-ray burst (GRB) pulse is energy dependent and that it decreases as a power-law function with increasing photon energy. In this work we have investigated the relation between the energy dependence of the pulse and the so-called Band spectrum by using a sample including 51 well-separated fast rise and exponential decay long-duration GRB pulses observed by BATSE (Burst and Transient Source Experiment on the Compton Gamma Ray Observatory). We first decompose these pulses into rise and decay phases and find that the rise widths and the decay widths also behave as a power-law function with photon energy. Then we investigate statistically the relations between the three power-law indices of the rise, decay, and total width of the pulse (denoted as {delta}{sub r}, {delta}{sub d}, and {delta}{sub w}, respectively) and the three Band spectral parameters, high-energy index ({alpha}), low-energy index ({beta}), and peak energy (E{sub p} ). It is found that (1) {alpha} is strongly correlated with {delta}{sub w} and {delta}{sub d} but seems uncorrelated with {delta}{sub r}; (2) {beta} is weakly correlated with the three power-law indices, and (3) E{sub p} does not show evident correlations with the three power-law indices. We further investigate the origin of {delta}{sub d}-{alpha} and {delta}{sub w}-{alpha}. We show that the curvature effect and the intrinsic Band spectrum could naturally lead to the energy dependence of the GRB pulse width and also the {delta}{sub d}-{alpha} and {delta}{sub w}-{alpha} correlations. Our results hold so long as the shell emitting gamma rays has a curved surface and the intrinsic spectrum is a Band spectrum or broken power law. The strong {delta}{sub d}-{alpha} correlation and inapparent correlations between {delta}{sub r} and the three Band spectral parameters also suggest that the rise and decay phases of the GRB pulses have different origins.

  6. The width of the solitary wave in dusty plasma

    NASA Astrophysics Data System (ADS)

    Malekolkalami, Behrooz; Alipanah, Amjad

    2016-01-01

    The Sagdeev potential method is employed to compute the width of the ion-acoustic solitary wave propagated in a dusty plasma containing three components (dust-ion-electron). The results indicate that the width is a continuous function over the allowable ranges of plasma parameters. The complexity of the resulting equations is an obstacle to the expression of the width function in an explicit form in terms of the parameters. Thus, computer algebra is needed to plot the graph of the width function versus the parameters, which helps us to understand the width changes as the parameters change.

  7. Global synchronization of parallel processors using clock pulse width modulation

    SciTech Connect

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  8. Phosphorylation-independent stimulation of DNA topoisomerase II alpha activity.

    PubMed

    Kimura, K; Saijo, M; Tanaka, M; Enomoto, T

    1996-05-01

    It has been suggested that casein kinase II phosphorylates DNA topoisomerase II alpha (topo II alpha) in mouse FM3A cells, by comparison of phosphopeptide maps of topo II alpha labeled in intact cells and of topo II alpha phosphorylated by various kinases in vitro. The phosphorylation of purified topo II alpha by casein kinase II, which attached a maximum of two phosphate groups per topo II alpha molecule, had no effect on the activity of topo II alpha. Dephosphorylation of purified topo II alpha by potato acid phosphatase, which almost completely dephosphorylated the topo II alpha, did not reduce the activity of topo II alpha. The incubation itself, regardless of phosphorylation or dephosphorylation status, stimulated the enzyme activity in both reactions. Topo II alpha activity was stimulated by incubation in a medium containing low concentrations of glycerol but not in that containing high concentrations of glycerol, such as the 50% in which purified topo II alpha is stored. The stimulation of topo II alpha activity by incubation was dependent on the concentration of topo II alpha, requiring a relatively high concentration of topo II alpha. PMID:8631919

  9. SOL Width Scaling in the MAST Tokamak

    NASA Astrophysics Data System (ADS)

    Ahn, Joon-Wook; Counsell, Glenn; Connor, Jack; Kirk, Andrew

    2002-11-01

    Target heat loads are determined in large part by the upstream SOL heat flux width, Δ_h. Considerable effort has been made in the past to develop analytical and empirical scalings for Δh to allow reliable estimates to be made for the next-step device. The development of scalings for a large spherical tokamak (ST) such as MAST is particularly important both for development of the ST concept and for improving the robustness of scalings derived for conventional tokamaks. A first such scaling has been developed in MAST DND plasmas. The scaling was developed by flux-mapping data from the target Langmuir probe arrays to the mid-plane and fitting to key upstream parameters such as P_SOL, bar ne and q_95. In order to minimise the effects of co-linearity, dedicated campaigns were undertaken to explore the widest possible range of each parameter while keeping the remainder as fixed as possible. Initial results indicate a weak inverse dependence on P_SOL and approximately linear dependence on bar n_e. Scalings derived from consideration of theoretical edge transport models and integration with data from conventional devices is under way. The established scaling laws could be used for the extrapolations to the future machine such as Spherical Tokamak Power Plant (STPP). This work is jointly funded by Euratom and UK Department of Trade and Industry. J-W. Ahn would like to recognise the support of a grant from the British Foreign & Commonwealth Office.

  10. Absolute decay width measurements in 16O

    NASA Astrophysics Data System (ADS)

    Wheldon, C.; Ashwood, N. I.; Barr, M.; Curtis, N.; Freer, M.; Kokalova, Tz; Malcolm, J. D.; Spencer, S. J.; Ziman, V. A.; Faestermann, Th; Krücken, R.; Wirth, H.-F.; Hertenberger, R.; Lutter, R.; Bergmaier, A.

    2012-09-01

    The reaction 126C(63Li, d)168O* at a 6Li bombarding energy of 42 MeV has been used to populate excited states in 16O. The deuteron ejectiles were measured using the high-resolution Munich Q3D spectrograph. A large-acceptance silicon-strip detector array was used to register the recoil and break-up products. This complete kinematic set-up has enabled absolute α-decay widths to be measured with high-resolution in the 13.9 to 15.9 MeV excitation energy regime in 16O; many for the first time. This energy region spans the 14.4 MeV four-α breakup threshold. Monte-Carlo simulations of the detector geometry and break-up processes yield detection efficiencies for the two dominant decay modes of 40% and 37% for the α+12C(g.s.) and a+12C(2+1) break-up channels respectively.

  11. A study of presynaptic alpha2-autoreceptors in alpha2A/D-, alpha2B- and alpha2C-adrenoceptor-deficient mice.

    PubMed

    Trendelenburg, A U; Klebroff, W; Hein, L; Starke, K

    2001-08-01

    The function of presynaptic alpha2-autoreceptors was studied in the hippocampus, occipito-parietal cortex, atria and vas deferens of NMRI mice, mice in which the alpha2A/D-, the alpha2B- or alpha2c-adrenoceptor gene had been disrupted (alpha2A/DKO, alpha2BKO and alpha2CKO, respectively), and the wildtype mice from which the knockout animals had been generated. Tissue pieces were preincubated with 3H-noradrenaline and then superfused and stimulated electrically. The alpha2-adrenoceptor agonist medetomidine reduced the electrically evoked overflow of tritium in all tissues from all mouse strains (stimulation with single pulses or single high-frequency pulse trains, called POPs, i.e. pulse patterns leading to minimal autoinhibition). The effects of medetomidine did not differ in NMRI, wildtype, alpha2BKO and alpha2CKO mice but were greatly reduced in alpha2A/DKO brain preparations and to a lesser extent in alpha2A/DKO atria and vasa deferentia. Six drugs were tested as antagonists against medetomidine. Their pKd values indicated that the hippocampal and occipito-parietal alpha2-autoreceptors in NMRI and wildtype mice were alpha2D (the rodent variant of the alpha2A/D-adrenoceptor) whereas the atrial and vas deferens alpha2-autoreceptors in NMRI and wildtype mice could not be identified with a single alpha2 subtype. Deletion of the alpha2A/D gene changed the pKd values in all tissues so that they now reflected alpha2C properties, whereas deletion of the alpha2C gene changed the pKd values in atria and vasa deferentia so that they now had alpha2D properties (as they had in NMRI and wildtype brain preparations). Autoinhibition by released noradrenaline was created using trains of up to 64 pulses or up to 4 POPs, and the overflow-enhancing effect of the alpha2 antagonist rauwolscine was determined. Results did not differ, irrespective of whether preparations were obtained from NMRI, wildtype, alpha2BKO or alpha2CKO mice: the overflow of tritium elicited by p pulses or POPs

  12. Equivalent width evaluation methods for Doppler, Lorentz, and Voigt profiles.

    PubMed

    Habib, Abdel Aziz M; Rammah, Yasser S

    2014-01-01

    An accurate technique has been developed to calculate the equivalent width of absorption lines. The calculations have been carried out for the pure Doppler and pure Lorentz limiting forms of the equivalent width. A novel expression for the equivalent width for Lorentz profile is given from direct integration of the line profile. The more general case of a Voigt profile leads to an analytical formula that permits a rapid estimate of the equivalent width for a wide range of maximum optical depths. The reliability of the approach is verified using a numerical application calculating the equivalent width for nickel resonance lines at 232.0 and 352.3 nm from atomic absorption (AA) measurements. The dependence of equivalent width on the number density of absorbing atoms is also provided. The results obtained for the equivalent width for the Voigt profile were compared with the data in the available literature obtained by different approaches. PMID:24480275

  13. alpha-Hexachlorocyclohexane (alpha-HCH)

    Integrated Risk Information System (IRIS)

    alpha - Hexachlorocyclohexane ( alpha - HCH ) ; CASRN 319 - 84 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Ass

  14. Downflow width behavior of Martian and terrestrial lava flows

    NASA Astrophysics Data System (ADS)

    Peitersen, Matthew N.; Crown, David A.

    1999-04-01

    Examination of the downflow width behavior of 59 terrestrial lava flows at Puu Oo (Hawaii) and Glass Mountain (California) and 86 Martian flows at Alba Patera, Tyrrhena Patera, Elysium, and Olympus Mons was completed using aerial photographs, topographic maps, previously published flow maps, and Viking Orbiter images. The examined lava flows exhibit diverse width behavior, from which information about flow processes and conditions was assessed. For Puu Oo flows, no significant correlation was found between the average width of a flow and flow length or average underlying slope. A significant, but weak relationship was found between average width and average flow thickness. In analyses of the downflow width behavior of individual flows, no consistent correlations were observed between width and thickness or underlying slope. When width was analyzed as a function of distance from the source for all flows, a variety of flow width behavioral trends were recognized and quantitatively classified. The most common behavior observed on Earth and Mars involved variations of width (sometimes significant) about a mean without a significant downflow narrowing or widening trend. The distributions of width behavior trends for the Alba Patera and Puu Oo flows examined were similar, with this type of ``constant'' behavior dominating. In contrast, Tyrrhena Patera flows showed a tendency to widen with distance downflow, and silicic flows at Glass Mountain were more likely to narrow. Flows were also subdivided by distance from the vent, and the width behavior of each division classified. Subdivision of flows resulted in significant changes in the classification of width behavior. While width behavior in the medial regions of flows was similar to that over entire flow lengths, proximal regions show more variability (possibly due to greater fluidity of lavas near the vent) and distal regions tend to uniformly narrow (possibly due to limited supply). In certain cases, classification and

  15. Excitation of high-n toroidicity-induced shear Alfven eigenmodes by energetic particles and fusion alpha particles in tokamaks

    SciTech Connect

    Fu, G.Y.; Cheng, C.Z.

    1992-07-01

    The stability of high-n toroidicity-induced shear Alfven eigenmodes (TAE) in the presence of fusion alpha particles or energetic ions in tokamaks is investigated. The TAE modes are discrete in nature and thus can easily tap the free energy associated with energetic particle pressure gradient through wave particle resonant interaction. A quadratic form is derived for the high-n TAE modes using gyro-kinetic equation. The kinetic effects of energetic particles are calculated perturbatively using the ideal MHD solution as the lowest order eigenfunction. The finite Larmor radius (FLR) effects and the finite drift orbit width (FDW) effects are included for both circulating and trapped energetic particles. It is shown that, for circulating particles, FLR and FDW effects have two opposite influences on the stability of the high-n TAE modes. First, they have the usual stabilizing effects by reducing the wave particle interaction strength. Second, they also have destabilizing effects by allowing more particles to resonate with the TAE modes. It is found that the growth rate induced by the circulating alpha particles increase linearly with toroidal mode number n for small {kappa}{sub {theta}}{rho}{sub {alpha}}, and decreases as 1/n for {kappa}{sub {theta}}{rho}{sub {alpha}} {much_gt} 1. The maximum growth rate is obtained at {kappa}{sub {theta}}{rho}{sub {alpha}} on the order of unity and is nearly constant for the range of 0.7 < {upsilon}{sub {alpha}}/{upsilon}{sub A} < 2.5. On the other hand, the trapped particle response is dominated by the precessional drift resonance. The bounce resonant contribution is negligible. The growth rate peaks sharply at the value of {kappa}{sub {theta}}{rho}{sub {alpha}} such that the precessional drift resonance occurs for the most energetic trapped particles. The maximum growth rate due to the energetic trapped particles is comparable to that of circulating particles.

  16. Excitation of high-n toroidicity-induced shear Alfven eigenmodes by energetic particles and fusion alpha particles in tokamaks

    SciTech Connect

    Fu, G.Y.; Cheng, C.Z.

    1992-07-01

    The stability of high-n toroidicity-induced shear Alfven eigenmodes (TAE) in the presence of fusion alpha particles or energetic ions in tokamaks is investigated. The TAE modes are discrete in nature and thus can easily tap the free energy associated with energetic particle pressure gradient through wave particle resonant interaction. A quadratic form is derived for the high-n TAE modes using gyro-kinetic equation. The kinetic effects of energetic particles are calculated perturbatively using the ideal MHD solution as the lowest order eigenfunction. The finite Larmor radius (FLR) effects and the finite drift orbit width (FDW) effects are included for both circulating and trapped energetic particles. It is shown that, for circulating particles, FLR and FDW effects have two opposite influences on the stability of the high-n TAE modes. First, they have the usual stabilizing effects by reducing the wave particle interaction strength. Second, they also have destabilizing effects by allowing more particles to resonate with the TAE modes. It is found that the growth rate induced by the circulating alpha particles increase linearly with toroidal mode number n for small {kappa}{sub {theta}}{rho}{sub {alpha}}, and decreases as 1/n for {kappa}{sub {theta}}{rho}{sub {alpha}} {much gt} 1. The maximum growth rate is obtained at {kappa}{sub {theta}}{rho}{sub {alpha}} on the order of unity and is nearly constant for the range of 0.7 < {upsilon}{sub {alpha}}/{upsilon}{sub A} < 2.5. On the other hand, the trapped particle response is dominated by the precessional drift resonance. The bounce resonant contribution is negligible. The growth rate peaks sharply at the value of {kappa}{sub {theta}}{rho}{sub {alpha}} such that the precessional drift resonance occurs for the most energetic trapped particles. The maximum growth rate due to the energetic trapped particles is comparable to that of circulating particles.

  17. Statistical evaluation of metal fill widths for emulated metal fill in parasitic extraction methodology

    NASA Astrophysics Data System (ADS)

    J-Me, Teh; Noh, Norlaili Mohd.; Aziz, Zalina Abdul

    2015-05-01

    In the chip industry today, the key goal of a chip development organization is to develop and market chips within a short time frame to gain foothold on market share. This paper proposes a design flow around the area of parasitic extraction to improve the design cycle time. The proposed design flow utilizes the usage of metal fill emulation as opposed to the current flow which performs metal fill insertion directly. By replacing metal fill structures with an emulation methodology in earlier iterations of the design flow, this is targeted to help reduce runtime in fill insertion stage. Statistical design of experiments methodology utilizing the randomized complete block design was used to select an appropriate emulated metal fill width to improve emulation accuracy. The experiment was conducted on test cases of different sizes, ranging from 1000 gates to 21000 gates. The metal width was varied from 1 x minimum metal width to 6 x minimum metal width. Two-way analysis of variance and Fisher's least significant difference test were used to analyze the interconnect net capacitance values of the different test cases. This paper presents the results of the statistical analysis for the 45 nm process technology. The recommended emulated metal fill width was found to be 4 x the minimum metal width.

  18. Ag contact properties according to the front grid width and firing temperature for silicon solar cells.

    PubMed

    Kim, Seongtak; Park, Sungeun; Kim, Young Do; Bae, Soohyun; Boo, Hyunpil; Kim, Hyunho; Lee, Kyung Dong; Tark, Sung Ju; Kim, Donghwan

    2014-10-01

    The effect of peak firing temperature and grid width on the contact properties between Ag metal and silicon (n+ emitter) was investigated for screen-printed silicon solar cells. We confirmed the factors that control the specific contact resistance as follows: (1) the Ag coverage fraction on the silicon surface, d(2) the thickness of the glass layer and (3) the etching depth on the n+ emitter region. The lowest specific contact resistance (8.27 mΩ x cm2) was obtained at the optimum firing temperature (720 degrees C). We also found that the grid width affected the contact quality of Ag paste because the contact width related to the absorbed heat of samples in RTP system. For this reason, when the grid width was further reduced, meaning more heat absorption, more Ag crystallites grew and the glass layer thickened. Light I-V results of a 6-inch silicon solar cell with minimum busbar width were similar to the PC1D simulation results. The efficiency was improved by 0.2% with the reduction of the busbar width. PMID:25942864

  19. Stance width changes how sensory feedback is used for multisegmental balance control.

    PubMed

    Goodworth, Adam D; Mellodge, Patricia; Peterka, Robert J

    2014-08-01

    A multilink sensorimotor integration model of frontal plane balance control was developed to determine how stance width influences the use of sensory feedback in healthy adults. Data used to estimate model parameters came from seven human participants who stood on a continuously rotating surface with three different stimulus amplitudes, with eyes open and closed, and at four different stance widths. Dependent variables included lower body (LB) and upper body (UB) sway quantified by frequency-response functions. Results showed that stance width had a major influence on how parameters varied across stimulus amplitude and between visual conditions. Active mechanisms dominated LB control. At narrower stances, with increasing stimulus amplitude, subjects used sensory reweighting to shift reliance from proprioceptive cues to vestibular and/or visual cues that oriented the LB more toward upright. When vision was available, subjects reduced reliance on proprioception and increased reliance on vision. At wider stances, LB control did not exhibit sensory reweighting. In the UB system, both active and passive mechanisms contributed and were dependent on stance width. UB control changed across stimulus amplitude most in wide stance (opposite of the pattern found in LB control). The strong influence of stance width on sensory integration and neural feedback control implies that rehabilitative therapies for balance disorders can target different aspects of balance control by using different stance widths. Rehabilitative strategies designed to assess or modify sensory reweighting will be most effective with the use of narrower stances, whereas wider stances present greater challenges to UB control. PMID:24760788

  20. Stance width changes how sensory feedback is used for multisegmental balance control

    PubMed Central

    Mellodge, Patricia; Peterka, Robert J.

    2014-01-01

    A multilink sensorimotor integration model of frontal plane balance control was developed to determine how stance width influences the use of sensory feedback in healthy adults. Data used to estimate model parameters came from seven human participants who stood on a continuously rotating surface with three different stimulus amplitudes, with eyes open and closed, and at four different stance widths. Dependent variables included lower body (LB) and upper body (UB) sway quantified by frequency-response functions. Results showed that stance width had a major influence on how parameters varied across stimulus amplitude and between visual conditions. Active mechanisms dominated LB control. At narrower stances, with increasing stimulus amplitude, subjects used sensory reweighting to shift reliance from proprioceptive cues to vestibular and/or visual cues that oriented the LB more toward upright. When vision was available, subjects reduced reliance on proprioception and increased reliance on vision. At wider stances, LB control did not exhibit sensory reweighting. In the UB system, both active and passive mechanisms contributed and were dependent on stance width. UB control changed across stimulus amplitude most in wide stance (opposite of the pattern found in LB control). The strong influence of stance width on sensory integration and neural feedback control implies that rehabilitative therapies for balance disorders can target different aspects of balance control by using different stance widths. Rehabilitative strategies designed to assess or modify sensory reweighting will be most effective with the use of narrower stances, whereas wider stances present greater challenges to UB control. PMID:24760788

  1. [Alpha-linolenic acid and cardiovascular diseases].

    PubMed

    Ristić-Medić, Danijela; Ristić, Gordana; Tepsić, Vesna

    2003-01-01

    IMPORTANCE AND METABOLISM OF ALPHA-LINOLENIC ACID: Alpha-linolenic acid is an essential fatty acid which cannot be produced in the body and must be taken by food. Both in animals and humans, alpha-linolenic acid is desaturated and elongated into eicosapentaenoic and docosahexaenoic acid. It is also incorporated into plasma and tissue lipids and its conversion is affected by levels of linoleic acid. POTENTIAL ROLE IN PATHOGENESIS OF CARDIOVASCULAR DISEASES: Diet enriched in n-3 fatty acids, especially alpha-linolenic acid, reduces the incidence of cardiac death. Studies have shown that alpha linolenic acid prevents ventricular fibrillation which is the main cause of cardiac death. Studies in rats suggest that alpha-linolenic acid may be more effective in preventing ventricular fibrillations than eicosapentaenoic and docosahexaenoic acid. Furthermore, alpha-linolenic acid is the main fatty acid decreasing platalet aggregation which is an important step in thrombosis i.e. non-fatal myocardial infarction and stroke. DIETARY SOURCES AND NUTRITION RECOMMENDATIONS: Dietary sources include flaxseed and flaxseed oil, canola oil, soybean and soybean oil, pumpkin seed and pumpkin oil, walnuts and walnut oil. Strong evidence supports beneficial effects of alpha-linolenic acid and its dietary sources should be incorporated into balanced diet for prevention of cardiovascular diseases. The recommended daily intake is 2 g with a ratio of 5/1 for linoleic/alpha-linolenic acid. PMID:15510909

  2. Alpha-1 Antitrypsin Test

    MedlinePlus

    ... measures the level of the protein AAT in blood. Alpha-1 antitrypsin phenotype testing evaluates the amount and type of AAT being produced and compares it to normal patterns. Alpha-1 antitrypsin genotype testing ( DNA testing) can ...

  3. Alpha-1 antitrypsin test

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003715.htm Alpha-1 antitrypsin test To use the sharing features on this page, please enable JavaScript. Alpha-1 antitrypsin is a laboratory test to measure the ...

  4. Influence of pulse width and target density on pulsed laser deposition of thin YBaCuO film.

    SciTech Connect

    Vikram, S.

    1999-01-20

    We have studied the effects of temporal pulse width and target density on the deposition of thin films of YBaCuO. A 248nm excimer laser and an 825nm Ti-sapphire laser were used to conduct the experiments with pulse widths of 27 ns, 16 ns, and 150 fs, and target densities of 80% and 90%. Scanning electron microscope photomicrographs and profilometer traces show a striking difference between nanosecond and femtosecond laser irradiation. Shortening the pulse width reduced particulate formation, provided stoichiometry, and improved the film properties. Decreasing the target density raised the ablation rate, produced thicker but nonuniform films, and reduced particulate formation.

  5. Alpha glucosidase inhibitors.

    PubMed

    Kalra, Sanjay

    2014-04-01

    Alpha glucosidase inhibitors (AGIs) are a unique class of anti-diabetic drugs. Derived from bacteria, these oral drugs are enzyme inhibitors which do not have a pancreato -centred mechanism of action. Working to delay carbohydrate absorption in the gastrointestinal tract, they control postprandial hyperglycaemia and provide unquestioned cardiovascular benefit. Specially suited for a traditional Pakistani carbohydrate-rich diet, AGIs have been termed the 'untapped diamonds' of diabetology. The use of these oral antidiabetic drugs (OADs) that target pathophysiology in the early stages of type 2 diabetes, notably to reduce postprandial hyperglycaemia and hyperinsulinaemia will inevitably increase with time. This review describes the history of their development, mechanism of action, basic and clinical pharmacology, and suggests practical, evidence-based guidance for their optimal use. PMID:24864650

  6. The Alpha Centauri System.

    ERIC Educational Resources Information Center

    Soderblom, David R.

    1987-01-01

    Describes the Alpha Centauri star system, which is the closest star system to the sun. Discusses the difficulties associated with measurements involving Alpha Centauri, along with some of the recent advances in stellar seismology. Raises questions about the possibilities of planets around Alpha Centauri. (TW)

  7. Radiographic reference limits for cardiac width of budgerigars (Melopsittacus undulatus).

    PubMed

    Velayati, Mozhgan; Mirshahi, Ali; Razmyar, Jamshid; Azizzadeh, Mohammad

    2015-03-01

    Primary and secondary cardiovascular diseases are not uncommon in birds. Although radiologic standards for heart width have been developed for mammals, they are still not available for many avian species. The purpose of this study was to establish normal reference values for cardiac size in budgerigar (Melopsittacus undulatus), one of the most popular pet bird species all over the world. After clinical and radiographic (lateral and ventrodorsal views) evaluations, 27 adult, clinically healthy budgerigars (10 females and 17 males) were included in this study. High-quality ventrodorsal and lateral radiographic projections were obtained. The cardiac and thoracic width, distance between third and fourth ribs, synsacrum width, coracoid width, and the distance between clavicle bones were measured on ventrodorsal radiographs. The ratio between cardiac width and other mentioned indices was calculated. Correlation of each anatomical index with the cardiac width was evaluated by linear regression model. Sex and weight were included in all models. Mean + SD of cardiac width was 10.8 +/- 0.6 mm, with lower and upper limits of 9.5 and 12.0 mm. The results showed a significant correlation between the cardiac width and the thoracic width (R2 = 0.28; P = 0.005). There were no significant associations between weight, sex, and the heart width. The values and ratios obtained in this study can be used as a reference of normal cardiac size of budgerigar in radiology for detection of cardiomegaly in this bird. PMID:25831574

  8. Scanning laser tomography Z profile signal width as an objective index of macular retinal thickening

    PubMed Central

    Hudson, C.; Flanagan, J.; Turner, G.; McLeod, D.

    1998-01-01

    AIMS—(i) To evaluate the relation between retinal thickness and the Z profile signal width of a scanning laser tomographer in selected patients exhibiting clinically manifest and circumscribed macular retinal thickening; (ii) to compare the Z profile signal width values of a group of age similar normal subjects with those of the patients with macular retinal thickening; and (iii) to present the methodology underlying the Z profile signal width derivation.
METHODS—Three patients with the following conditions were selected: widespread diabetic macular oedema; localised diabetic macular oedema; and macular hole. The patients were selected because they exhibited clinically manifest and circumscribed macular retinal thickening. Patients underwent fundus photography and a clinical examination which included fundus biomicroscopy. Fourteen age similar normal subjects were also assessed. The Heidelberg retina tomograph (HRT) was utilised to acquire seven topographic images of each macula. Z profile signal width data were analysed using custom software. Signal width was measured at 50% of the maximum intensity.
RESULTS—For each patient with macular retinal thickening, Z profile signal width analysis (after normalisation to reduce the influence of variation in reflectance intensity between successive images) revealed a significant (p<0.0001) localised increase of signal width which agreed with the HRT topographic analysis of retinal height, and also the clinical assessment of retinal thickness. The mean normalised Z profile signal width for the normal subjects (assessed over the whole image) ranged from 0.278 (SD 0.039) to 0.444 (0.063); these values compared with those obtained from patients in areas of macular retinal thickening of 0.761 (0.224) to 0.953 (0.194). Z profile signal width test-retest data for the patient with localised diabetic macular oedema were plus or minus 0.159 which compared with a mean signal width value of 0.761.

  9. Correcting Coefficient Alpha for Correlated Errors: Is [alpha][K]a Lower Bound to Reliability?

    ERIC Educational Resources Information Center

    Rae, Gordon

    2006-01-01

    When errors of measurement are positively correlated, coefficient alpha may overestimate the "true" reliability of a composite. To reduce this inflation bias, Komaroff (1997) has proposed an adjusted alpha coefficient, ak. This article shows that ak is only guaranteed to be a lower bound to reliability if the latter does not include correlated…

  10. Experimental and Theoretical Electron Density Distribution of Alpha,Alpha-Trehalose Dihydrate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alpha,alpha-rehalose is of interest because of its cryoprotective and antidessicant properties, and because it possesses various technical anomalies such as 13C NMR spectra that give misleading indications of intramolecular structural symmetry. It is a non-reducing disaccharide, with the glycosidic...

  11. Manipulation of two alpha-endo-beta-1,4-glucanase genes, AtCel6 and GmCel7, reduces susceptibility to Heterodera glycines in soybean roots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant endo-beta-1,4-glucanases (EGases) include cell-wall-modifying enzymes that are involved in nematode-induced growth of syncytia (feeding structures) in nematode-infected roots. EGases in the alpha and beta subfamilies contain signal peptides and are secreted, while those in the gamma subfamily ...

  12. Influence of the {alpha}-d motion in {sup 6}Li on Trojan horse applications

    SciTech Connect

    Pizzone, R.G.; Spitaleri, C.; Cherubini, S.; La Cognata, M.; Lamia, L.; Musumarra, A.; Romano, S.; Tumino, A.; Tudisco, S.; Miljanic, D.; Typel, S.

    2005-05-01

    The {alpha}-d cluster structure of {sup 6}Li has been extensively investigated in the past few decades. In particular the width of the {alpha} momentum distribution in {sup 6}Li has been studied as a function of the transferred momentum. These investigations are now reviewed and updated after recent experiments. Trojan horse method applications are also discussed because the momentum distribution of the spectator particle inside the Trojan horse nucleus is a necessary input for this method. The impact of the width (FWHM) variation in the extraction of the astrophysical S(E) factor is discussed for the {sup 6}Li(d,{alpha}){sup 4}He reaction.

  13. Compact pulse width modulation circuitry for silicon photomultiplier readout.

    PubMed

    Bieniosek, M F; Olcott, P D; Levin, C S

    2013-08-01

    The adoption of solid-state photodetectors for positron emission tomography (PET) system design and the interest in 3D interaction information from PET detectors has lead to an increasing number of readout channels in PET systems. To handle these additional readout channels, PET readout electronics should be simplified to reduce the power consumption, cost, and size of the electronics for a single channel. Pulse-width modulation (PWM), where detector pulses are converted to digital pulses with width proportional to the detected photon energy, promises to simplify PET readout by converting the signals to digital form at the beginning of the processing chain, and allowing a single time-to-digital converter to perform the data acquisition for many channels rather than routing many analogue channels and digitizing in the back end. Integrator based PWM systems, also known as charge-to-time converters (QTCs), are especially compact, reducing the front-end electronics to an op-amp integrator with a resistor discharge, and a comparator. QTCs, however, have a long dead-time during which dark count noise is integrated, reducing the output signal-to-noise ratio. This work presents a QTC based PWM circuit with a gated integrator that shows performance improvements over existing QTC based PWM. By opening and closing an analogue switch on the input of the integrator, the circuit can be controlled to integrate only the portions of the signal with a high signal-to-noise ratio. It also allows for multiplexing different detectors into the same PWM circuit while avoiding uncorrelated noise propagation between photodetector channels. Four gated integrator PWM circuits were built to readout the spatial channels of two position sensitive solid-state photomultiplier (PS-SSPM). Results show a 4 × 4 array 0.9 mm × 0.9 mm × 15 mm of LYSO crystals being identified on the 5 mm × 5 mm PS-SSPM at room temperature with no degradation for twofold multiplexing. In principle, much larger

  14. Compact Pulse Width Modulation Circuitry for Silicon Photomultiplier Readout

    PubMed Central

    Bieniosek, M F; Olcott, P D; Levin, C S

    2013-01-01

    The adoption of solid state photo-detectors for positron emission tomography (PET) system design and the interest in 3D interaction information from PET detectors has lead to an increasing number of readout channels in PET systems. To handle these additional readout channels, PET readout electronics should be simplified to reduce the power consumption, cost, and size of the electronics for a single channel. Pulse width modulation (PWM), where detector pulses are converted to digital pulses with width proportional to the detected photon energy, promises to simplify PET readout by converting the signals to digital form at the beginning of the processing chain, and allowing a single time-to-digital converter to perform the data acquisition for many channels rather than routing many analog channels and digitizing in the back end. Integrator based PWM systems, also known as charge-to-time converters (QTC), are especially compact, reducing the front-end electronics to an op-amp integrator with a resistor discharge, and a comparator. QTCs, however, have a long dead-time during which dark count noise is integrated, reducing the output signal to noise ratio. This work presents a QTC based PWM circuit with a gated integrator that shows performance improvements over existing QTC based PWM. By opening and closing an analog switch on the input of the integrator, the circuit can be controlled to integrate only the portions of the signal with a high signal-to-noise ratio. It also allows for multiplexing different detectors into the same PWM circuit while avoiding uncorrelated noise propagation between photodetector channels. Four gated integrator PWM circuits were built to readout the spatial channels of two position sensitive solid state photomultiplier (PS-SSPM). Results show a 4×4 array 0.9mm×0.9mm×15mm of LYSO crystals being identified on the 5mm×5mm PS-SSPM at room temperature with no degradation for 2-fold multiplexing. In principle, much larger multiplexing ratios are

  15. Compact pulse width modulation circuitry for silicon photomultiplier readout

    NASA Astrophysics Data System (ADS)

    Bieniosek, M. F.; Olcott, P. D.; Levin, C. S.

    2013-08-01

    The adoption of solid-state photodetectors for positron emission tomography (PET) system design and the interest in 3D interaction information from PET detectors has lead to an increasing number of readout channels in PET systems. To handle these additional readout channels, PET readout electronics should be simplified to reduce the power consumption, cost, and size of the electronics for a single channel. Pulse-width modulation (PWM), where detector pulses are converted to digital pulses with width proportional to the detected photon energy, promises to simplify PET readout by converting the signals to digital form at the beginning of the processing chain, and allowing a single time-to-digital converter to perform the data acquisition for many channels rather than routing many analogue channels and digitizing in the back end. Integrator based PWM systems, also known as charge-to-time converters (QTCs), are especially compact, reducing the front-end electronics to an op-amp integrator with a resistor discharge, and a comparator. QTCs, however, have a long dead-time during which dark count noise is integrated, reducing the output signal-to-noise ratio. This work presents a QTC based PWM circuit with a gated integrator that shows performance improvements over existing QTC based PWM. By opening and closing an analogue switch on the input of the integrator, the circuit can be controlled to integrate only the portions of the signal with a high signal-to-noise ratio. It also allows for multiplexing different detectors into the same PWM circuit while avoiding uncorrelated noise propagation between photodetector channels. Four gated integrator PWM circuits were built to readout the spatial channels of two position sensitive solid-state photomultiplier (PS-SSPM). Results show a 4 × 4 array 0.9 mm × 0.9 mm × 15 mm of LYSO crystals being identified on the 5 mm × 5 mm PS-SSPM at room temperature with no degradation for twofold multiplexing. In principle, much larger

  16. Biologic width and its importance in periodontal and restorative dentistry.

    PubMed

    Nugala, Babitha; Kumar, Bb Santosh; Sahitya, S; Krishna, P Mohana

    2012-01-01

    An adequate understanding of the relationship between periodontal tissues and restorative dentistry is paramount to ensure adequate form, function, esthetics and comfort of the dentition. While most clinicians are aware of this important relationship, uncertainty remains regarding specific concepts such as biologic width, its maintenance and applications of crown lengthening in cases of biologic width violation. Relevant publications regarding biologic width, its violation and management were identified up to August 2011 using manual and electronic database search in Medline, Embase, Directory of Open Access Journals and Google Scholar. This review discusses the concept of biologic width around tooth and its relationship to periodontal health and restorative dentistry. PMID:22368328

  17. Calibration issues in delta alpha /alpha .

    NASA Astrophysics Data System (ADS)

    Molaro, Paolo; Centurión, Miriam; Levshakov, Sergei

    Laser Comb Wavelength calibration shows that the ThAr one is locally unreliable with possible deviations of up to 100 {m s}-1 within one order range, while delivering an overall 1 {m s}-1 accuracy (Wilken et al 2009). Such deviation corresponds to delta alpha /alpha ≈ 7* 10-6 for a Fe II-Mg II pair. Comparison of line shifts among the 5 Fe II lines, with almost identical sensitivity to fine structure constant changes, offers a clean way to directly test the presence of possible local wavelength calibration errors of whatever origin. We analyzed 5 absorption systems, with zabs ranging from 1.15 to 2.19 towards 3 bright QSOs. The results show that while some lines are aligned within 20 {m s}-1, others reveal large deviations reaching 200 {m s}-1 or higher and corresponding to a delta alpha /alpha > 10-5 level. The origin of these deviations is not clearly identified but could be related to the adaptation of wavelength calibration to CCD manufacturing irregularities. These results suggest that to draw conclusions from delta alpha /alpha analysis based on one or only few lines must be done with extreme care.

  18. Solar wind suprathermal electron Stahl widths across high-speed stream structures

    SciTech Connect

    Skoug, Ruth M; Steinberg, John T; Goodrich, Katherine A; Anderson, Brett R

    2011-01-03

    Suprathermal electrons (100-1500 eV) observed in the solar wind typically show a strahl distribution, that is, a beam directed away from the Sun along the magnetic field direction. The strahl width observed at 1 AU is highly variable, ranging from 10-70 degrees. The obsenred finite width of the strahl results from the competition between beam focusing as the interplanetary magnetic field strength drops with distance from the Sun, and pitch-angle scattering as the beam interacts with the solar wind plasma in transit from the sun. Here we examine strahl width, observed with ACE SWEPAM across high-speed stream structures to investigate variations in electron scattering as a function of local plasma characteristics. We find that narrow strahls (less than 20 degrees wide), indicating reduced scattering, are observed within high-speed streams. Narrow strahls are also observed in both very low temperature solar wind, in association with ICMEs. Case studies of high-speed streams typically show the strahl narrowing at the leading edge of the stream. In some cases, the strahl narrows at the reverse shock or pressure wave, in other cases at the stream interface. The narrowing can either occur discontinuously or gradually over a period of hours. Within the high-speed wind, the strahl remains narrow for a period of hours to days, and then gradually broadens. The strahl width is roughly constant at all energies across these structures. For some fraction of high-speed streams, counterstreaming is associated with passage of the corotating interaction region. In these cases, we find the widths of the two counterstreaming beams frequently differ by more than 40 degrees. This dramatic difference in strahl width contrasts with observations in the solar wind as a whole, in which counterstreaming strahls typically differ in width by less than 20 degrees.

  19. Implications of Satellite Swath Width on Global Aerosol Optical Thickness Statistics

    NASA Technical Reports Server (NTRS)

    Colarco, Peter; Kahn, Ralph; Remer, Lorraine; Levy, Robert; Welton, Ellsworth

    2012-01-01

    We assess the impact of swath width on the statistics of aerosol optical thickness (AOT) retrieved by satellite as inferred from observations made by the Moderate Resolution Imaging Spectroradiometer (MODIS). We sub-sample the year 2009 MODIS data from both the Terra and Aqua spacecraft along several candidate swaths of various widths. We find that due to spatial sampling there is an uncertainty of approximately 0.01 in the global, annual mean AOT. The sub-sampled monthly mean gridded AOT are within +/- 0.01 of the full swath AOT about 20% of the time for the narrow swath sub-samples, about 30% of the time for the moderate width sub-samples, and about 45% of the time for the widest swath considered. These results suggest that future aerosol satellite missions with only a narrow swath view may not sample the true AOT distribution sufficiently to reduce significantly the uncertainty in aerosol direct forcing of climate.

  20. Effect of Slag Thickness on Macrosegregation and Transition Zone Width of Electroslag Remelting Dual Alloy Ingot

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Yan, Hongguang; Ren, Neng; Li, Baokuan

    2016-01-01

    The influence of the slag thickness on macrosegregation and transition zone (TZ) width of electroslag remelting (ESR) dual alloy ingot was investigated. To produce a dual alloy ingot, an electrode, constituted by a CrMoV bar and a NiCrMoV alloy bar, was remelted by using the ESR process. The slag thickness ranged from 50 mm to 70 mm. The results indicate that the slag temperature and melt rate first increase and then decrease with the increasing of the slag thickness. The metal sump depth, however, monotonically decreases. The most pronounced macrosegregation is found when the slag thickness is 50 mm and is alleviated with a thicker slag. The minimal TZ width appears when the slag thickness is 60 mm. Processing the ESR dual alloy ingot with a 60-mm slag layer is the best choice for reducing the TZ width and macrosegregation in the present work.

  1. Finite-width currents, magnetic shear, and the current-driven ion-cyclotron instability

    NASA Technical Reports Server (NTRS)

    Bakshi, P.; Ganguli, G.; Palmadesso, P.

    1983-01-01

    Our earlier results that non-local effects due to even a small magnetic shear produce a significant reduction of the growth rate of the ion cyclotron instability driven by a uniform current are now generalized to finite width currents. Externally prescribed as well as self-consistent shears are considered. If the current width Lc exceeds the shear length Ls, the previous results are recovered. Shear becomes less effective with reduction of Lc, and for typical parameters, the growth rate attains its (shearless) local value for Lc/Ls approximately less than 10 to the minus 2. Non-local effects of the finite current width itself come into play if Lc is further reduced to a few ion Larmor radii and can quench the instability. Previously announced in STAR as N83-28996

  2. Relating orogen width to shortening, erosion, and exhumation during Alpine collision

    NASA Astrophysics Data System (ADS)

    Rosenberg, C. L.; Berger, A.; Bellahsen, N.; Bousquet, R.

    2015-06-01

    We investigate along-strike width changes of the thickened, accreted lower plate (TALP) in the Central and in the Eastern Alps. We set the width of the TALP in relation to the inferred amount of collisional shortening and exhumation along six orogen-scale cross sections. Taking the present-day, along-strike gradients in the amount of collisional shortening to represent the temporal evolution of the collisional wedge, it may be concluded that the cross-sectional area of the TALP diminishes during ongoing shortening, indicating that the erosional flux outpaced the accretionary flux. Higher amounts of collisional shortening systematically coincide with smaller widths of the TALP and dramatic increases of the reconstructed eroded rock column. Higher amounts of shortening also coincide with larger amplitudes of orogen-scale, upright folds, with higher exhumation and with higher exhumation rates. Hence, erosion did play a major role in reducing by >30 km the vertical crustal thickness in order to accommodate and allow shortening by folding. Long-term climate differences cannot explain alternating changes of width by a factor of almost 2 along straight segments of the orogen on length scales less than 200 km, as observed from the western Central Alps to the easternmost Eastern Alps. Sedimentary or paleontological evidences supporting such paleo-climatic differences are lacking, suggesting that erosional processes did not directly control the width of the orogen.

  3. Measuring Slit Width and Separation in a Diffraction Experiment

    ERIC Educational Resources Information Center

    Gan, K. K.; Law, A. T.

    2009-01-01

    We present a procedure for measuring slit width and separation in single- and double-slit diffraction experiments. Intensity spectra of diffracted laser light are measured with an optical sensor (PIN diode). Slit widths and separations are extracted by fitting to the measured spectra. We present a simple fitting procedure to account for the…

  4. Laminin alpha1 chain mediated reduction of laminin alpha2 chain deficient muscular dystrophy involves integrin alpha7beta1 and dystroglycan.

    PubMed

    Gawlik, Kinga I; Mayer, Ulrike; Blomberg, Kristina; Sonnenberg, Arnoud; Ekblom, Peter; Durbeej, Madeleine

    2006-03-20

    Transgenically introduced laminin (LN) alpha1 chain prevents muscular dystrophy in LNalpha2 chain deficient mice. We now report increased integrin alpha7Bbeta1D synthesis in dystrophic LNalpha2 chain deficient muscle. Yet, immunofluorescence demonstrated a reduced expression of integrin alpha7B subunit at the sarcolemma. Transgenic expression of LNalpha1 chain reconstituted integrin alpha7B at the sarcolemma. Expression of alpha- and beta-dystroglycan is enhanced in LNalpha2 chain deficient muscle and normalized by transgenic expression of LNalpha1 chain. We suggest that LNalpha1 chain in part ameliorates the development of LNalpha2 chain deficient muscular dystrophy by retaining the binding sites for integrin alpha7Bbeta1D and alpha-dystroglycan, respectively. PMID:16504180

  5. Removal of alpha-Gal epitopes from porcine aortic valve and pericardium using recombinant human alpha galactosidase A.

    PubMed

    Park, Seongsik; Kim, Woong-Han; Choi, Sun-Young; Kim, Yong-Jin

    2009-12-01

    It has been reported that the immune response due to alpha-Gal epitopes is an important factor in tissue valve failure. The elimination of the interaction between the natural anti-Gal antibodies and alpha-gal epitopes on the xenografts is a prerequisite to the success of xenografts in humans. Previously, we reported that the green coffee bean alpha-galactosidase could remove all alpha-Gal epitopes from cell surface of porcine aortic valve and pericardial tissue, but it has limitations on cost effectiveness. In this study we wanted to know whether the recently produced recombinant human alpha-galactosidase A has the same effective enzymatic activity as green coffee bean alpha-galactosidase in removing alpha-Gal epitopes from the same tissues. After treating fresh porcine aortic valve and pericardial tissue with recombinant alpha-galactosidase A, each sample was stained with Griffonia simplicifolia type I isolectin B4 indirect immunoperoxidase avidin-biotin technique. We then examined whether the alpha-Gal epitopes were reduced or abolished in each consecutive concentration of recombinant alpha-galactosidase A by comparing the degree of the Griffonia simplicifolia isolectin B4 staining. As a result, the recombinant alpha-galactosidase A could remove cell surface alpha-Gals on porcine aortic valve and pericardial tissue as effectively as green coffee bean alpha-galactosidase. PMID:19949670

  6. Variations in solar Lyman alpha irradiance on short time scales

    NASA Technical Reports Server (NTRS)

    Pap, J. M.

    1992-01-01

    Variations in solar UV irradiance at Lyman alpha are studied on short time scales (from days to months) after removing the long-term changes over the solar cycle. The SME/Lyman alpha irradiance is estimated from various solar indices using linear regression analysis. In order to study the nonlinear effects, Lyman alpha irradiance is modeled with a 5th-degree polynomial as well. It is shown that the full-disk equivalent width of the He line at 1083 nm, which is used as a proxy for the plages and active network, can best reproduce the changes observed in Lyman alpha. Approximately 72 percent of the solar-activity-related changes in Lyman alpha irradiance arise from plages and the network. The network contribution is estimated by the correlation analysis to be about 19 percent. It is shown that significant variability remains in Lyman alpha irradiance, with periods around 300, 27, and 13.5d, which is not explained by the solar activity indices. It is shown that the nonlinear effects cannot account for a significant part of the unexplained variation in Lyman alpha irradiance. Therefore, additional events (e.g., large-scale motions and/or a systematic difference in the area and intensity of the plages and network observed in the lines of Ca-K, He 1083, and Lyman alpha) may explain the discrepancies found between the observed and estimated irradiance values.

  7. [Alpha1-adrenoceptor subtypes and alpha1-adrenoceptor antagonists].

    PubMed

    Muramatsu, Ikunobu; Suzuki, Fumiko; Tanaka, Takashi; Yamamoto, Hatsumi; Morishima, Shigeru

    2006-03-01

    Alpha(1)-adrenoceptors are widely distributed in the human body and play important physiologic roles. Three alpha(1)-adrenoceptor subtypes (alpha(1A), alpha(1B) and alpha(1D)) have been cloned and show different pharmacologic profiles. In addition, a putative alpha(1)-adrenoceptor (alpha(1L) subtype) has also been proposed. Recently, three drugs (tamsulosin, naftopidil, and silodosin) have been developed in Japan for the treatment of urinary obstruction in patients with benign prostatic hyperplasia. In this review, we describe recent alpha(1)-adrenoceptor subclassifications and the pharmacologic characteristics (subtype selectivity and clinical relevance) of alpha(1)-adrenoceptor antagonists. PMID:16518082

  8. Dynamical and Stellar Masses of Lyman-alpha Galaxies

    NASA Astrophysics Data System (ADS)

    Rhoads, James E.; Malhotra, S.; McLinden, E.; Richardson, M. L.; Finkelstein, S. L.; Tilvi, V. S.

    2012-01-01

    We have observed strong nebular lines of [OIII] and H alpha for Lyman-alpha galaxies at z=2-3.1 using Keck+NIRSPEC, LBT+LUCIFER, and Gemini+NIFS. [OIII] 5007 is strong enough to dominate the 2 micron K band fluxes of these galaxies, and leads to an overestimate of the stellar mass of the galaxy by an order of magnitude. After correcting for the observed [OIII] lines, we infer low masses and young ages for these galaxies. We also use the physical widths of the rest-optical lines, combined with spatial sizes from HST imaging, to obtain direct dynamical mass estimates of Lyman alpha galaxies (which cannot be done using the resonantly scattered Lyman alpha line). Finally, we combine our stellar mass estimates and line widths to place these galaxies on the baryonic Tully-Fisher relation. We find that the stellar masses required to reproduce the observed light are lower than one would expect based on the galaxies' line widths. The stellar mass densities of these galaxies are comparable to those of elliptical galaxies today. We gratefully acknowledge support from NSF grant NSF-AST-0808165.

  9. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel – a cadaveric study

    PubMed Central

    Li, Zong-Ming; Gabra, Joseph N.; Marquardt, Tamara L.; Kim, Dong Hee

    2013-01-01

    Background Carpal tunnel morphology plays an essential role in the etiology and treatment of carpal tunnel syndrome. The purpose of this study was to observe the morphological changes of the carpal tunnel as a result of carpal arch width narrowing. It was hypothesized carpal arch width narrowing would result in increased height and area of the carpal arch. Methods The carpal arch width of eight cadaveric hands was narrowed by a custom apparatus and cross-sectional ultrasound images were acquired. The carpal arch height and area were quantified as the carpal arch width was narrowed. Correlation and regression analyses were performed for the carpal arch height and area with respect to the carpal arch width. Findings The carpal tunnel became more convex as the carpal arch width was narrowed. The initial carpal arch width, height, and area were 25.7 (SD 1.9) mm, 4.1 (SD 0.6) mm, and 68.5 (SD 14.0) mm2, respectively. The carpal arch height and area negatively correlated with the carpal arch width, with correlation coefficients of −0.974 (SD 0.018) and −0.925 (SD 0.034), respectively. Linear regression analyses showed a 1 mm narrowing of the carpal arch width resulted in proportional increases of 0.40 (SD 0.14) mm in the carpal arch height and 4.0 (SD 2.2) mm2 in the carpal arch area. Interpretation This study demonstrates that carpal arch width narrowing leads to increased carpal arch height and area, a potential mechanism to reduce the mechanical insult to the median nerve and relieve symptoms associated with carpal tunnel syndrome. PMID:23583095

  10. RADIATIVE TRANSFER MODELING OF Ly{alpha} EMITTERS. I. STATISTICS OF SPECTRA AND LUMINOSITY

    SciTech Connect

    Zheng Zheng; Cen Renyue; Trac, Hy; Miralda-Escude, Jordi

    2010-06-10

    We combine a cosmological reionization simulation with box size of 100 h {sup -1} Mpc on a side and a Monte Carlo Ly{alpha} radiative transfer code to model Ly{alpha} Emitters (LAEs) at z {approx} 5.7. The model introduces Ly{alpha} radiative transfer as the single factor for transforming the intrinsic Ly{alpha} emission properties into the observed ones. Spatial diffusion of Ly{alpha} photons from radiative transfer results in extended Ly{alpha} emission and only the central part with high surface brightness can be observed. Because of radiative transfer, the appearance of LAEs depends on density and velocity structures in circumgalactic and intergalactic media as well as the viewing angle, which leads to a broad distribution of apparent (observed) Ly{alpha} luminosity for a given intrinsic Ly{alpha} luminosity. Radiative transfer also causes frequency diffusion of Ly{alpha} photons. The resultant Ly{alpha} line is asymmetric with a red tail. The peak of the Ly{alpha} line shifts toward longer wavelength and the shift is anti-correlated with the apparent-to-intrinsic Ly{alpha} luminosity ratio. The simple radiative transfer model provides a new framework for studying LAEs. It is able to explain an array of observed properties of z {approx} 5.7 LAEs in Ouchi et al., producing Ly{alpha} spectra, morphology, and apparent Ly{alpha} luminosity function (LF) similar to those seen in observation. The broad distribution of apparent Ly{alpha} luminosity at fixed UV luminosity provides a natural explanation for the observed UV LF, especially the turnover toward the low luminosity end. The model also reproduces the observed distribution of Ly{alpha} equivalent width (EW) and explains the deficit of UV bright, high EW sources. Because of the broad distribution of the apparent-to-intrinsic Ly{alpha} luminosity ratio, the model predicts effective duty cycles and Ly{alpha} escape fractions for LAEs.

  11. Influence of pulse width and detuning on coherent phonon generation

    NASA Astrophysics Data System (ADS)

    Nakamura, Kazutaka G.; Shikano, Yutaka; Kayanuma, Yosuke

    2015-10-01

    We investigated the coherent phonon generation mechanism by irradiation of an ultrashort pulse with a simple two-level model. Our derived formulation shows that both impulsive stimulated Raman scattering (ISRS) and impulsive absorption (IA) simultaneously occur, and phonon wave packets are generated in the electronic ground and excited states by ISRS and IA, respectively. We identify the dominant process from the amplitude of the phonon oscillation. For short pulse widths, ISRS is very small and becomes larger as the pulse width increases. We also show that the initial phase is dependent on the pulse width and the detuning.

  12. Bank stability and channel width adjustment, East Fork River, Wyoming.

    USGS Publications Warehouse

    Andrews, E.D.

    1982-01-01

    Frequent surveys of eight cross sections located in self-formed reaches of the East Fork River, Wyoming, during the 1974 snowmelt flood showed a close relation between channel morphology and scour and fill. Those cross sections narrower than the mean reach width filled at discharges less than bankfull and scoured at discharges greater than bankfull. Those cross sections wider than the mean reach width scoured at discharges less than bankfull and filled at discharges greater than bankfull. Bank stability, and to some extent the adjustment of stream channel width, in the East Fork River study reach appears to be controlled by the processes of scour and fill. -from Author

  13. Comparison of electron width models for fast line profile calculations

    NASA Astrophysics Data System (ADS)

    Iglesias, Carlos A.

    2016-03-01

    The first non-vanishing term in the perturbation expansion of the electron contribution to the line width, commonly used in spectral line broadening by plasmas, was previously expressed in terms of the thermally averaged bremsstrahlung Gaunt factor. The approximations in the derivation, however, suggest that the result is uncertain. The electron width formula is tested with the hydrogen Balmer series and found suspect. Calculations for the He II Lyman series also display similar difficulties. The limitation of this electron width formulation is traced to the absence of an explicit strong collision cutoff beyond which the second-order theory is invalid.

  14. Some comments on. cap alpha. /sub s/ and. lambda. /sub anti MS/

    SciTech Connect

    Durand, B.

    1984-09-01

    Some new determinations of the strong coupling constant ..cap alpha../sub s/ from hadronic and leptonic decay widths of quarkonia are added to the accumulation of data on ..cap alpha../sub s/ as a function of Q. When compared with the renormalization group prediction of 1/..cap alpha../sub s/ vs 1n Q, parameterized by the QCD scale parameter ..lambda../sub anti MS/, these new points do very little to resolve whether ..cap alpha../sub s/ runs as predicted, and if so, on which ..lambda../sub anti MS/ curve. 6 references.

  15. Latest updates in global flood modelling: channel bifurcation and global river width database

    NASA Astrophysics Data System (ADS)

    Yamazaki, D.; Kanae, S.; Hirabayashi, Y.; O'Loughlin, F.; Trigg, M. A.; Bates, P. D.

    2014-12-01

    Global flood modelling is a relatively new framework in earth system studies, and there still exist many rooms for improving model physics. A typical grid size of global models (generally >5 km) is coarser than the scale of the topography of river channels and floodplains, therefore flood dynamics in global flood models is represented by sub-grid parameterization. Here, we introduce two latest updates in flood dynamics parameterization, i.e. channel bifurcation scheme and global river width database. The upstream-downstream relationship of model grids is prescribed (i.e. parameterized) by a river network map, where each grid has been assumed to have only one downstream grid. We abandoned this "only one downstream" assumption, and succeeded to represent channel bifurcation in a global flood model. The new bifurcation scheme was tested in the Mekong River, and showed the importance of channel bifurcation in mega-delta hydrodynamics. Channel cross-sectional shape has been parameterized using an empirical equation of discharge (or drainage area), and it is a major source of uncertainties in global flood modelling. We recently developed a fully-automated algorithm to calculate river width from satellite water mask. By applying this algorithm to SRTM Water Body Data, the Global Width Database for Large Rivers (GWD-LR) was constructed. The difference between the satellite-based width and empirically-estimated width is very large, suggesting the difficulty of river width parameterization by an empirical equation. Improvement in flood dynamics parameterization reduces uncertainties in global flood simulations. This enables advanced validation/calibration of global flood models, such as direct comparison against satellite altimeters. A future strategy for advanced model validation/calibration will be mentioned in the conference presentation.

  16. Event counting alpha detector

    DOEpatents

    Bolton, Richard D.; MacArthur, Duncan W.

    1996-01-01

    An electrostatic detector for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure.

  17. Alpha-particle diagnostics

    SciTech Connect

    Young, K.M.

    1991-01-01

    This paper will focus on the state of development of diagnostics which are expected to provide the information needed for {alpha}- physics studies in the future. Conventional measurement of detailed temporal and spatial profiles of background plasma properties in DT will be essential for such aspects as determining heating effectiveness, shaping of the plasma profiles and effects of MHD, but will not be addressed here. This paper will address (1) the measurement of the neutron source, and hence {alpha}-particle birth profile, (2) measurement of the escaping {alpha}-particles and (3) measurement of the confined {alpha}-particles over their full energy range. There will also be a brief discussion of (4) the concerns about instabilities being generated by {alpha}-particles and the methods necessary for measuring these effects. 51 refs., 10 figs.

  18. Imaging alpha particle detector

    DOEpatents

    Anderson, D.F.

    1980-10-29

    A method and apparatus for detecting and imaging alpha particles sources is described. A dielectric coated high voltage electrode and a tungsten wire grid constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source to be quantitatively or qualitatively analyzed. A thin polyester film window allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

  19. Imaging alpha particle detector

    DOEpatents

    Anderson, David F.

    1985-01-01

    A method and apparatus for detecting and imaging alpha particles sources is described. A conducting coated high voltage electrode (1) and a tungsten wire grid (2) constitute a diode configuration discharge generator for electrons dislodged from atoms or molecules located in between these electrodes when struck by alpha particles from a source (3) to be quantitatively or qualitatively analyzed. A thin polyester film window (4) allows the alpha particles to pass into the gas enclosure and the combination of the glass electrode, grid and window is light transparent such that the details of the source which is imaged with high resolution and sensitivity by the sparks produced can be observed visually as well. The source can be viewed directly, electronically counted or integrated over time using photographic methods. A significant increase in sensitivity over other alpha particle detectors is observed, and the device has very low sensitivity to gamma or beta emissions which might otherwise appear as noise on the alpha particle signal.

  20. Event counting alpha detector

    DOEpatents

    Bolton, R.D.; MacArthur, D.W.

    1996-08-27

    An electrostatic detector is disclosed for atmospheric radon or other weak sources of alpha radiation. In one embodiment, nested enclosures are insulated from one another, open at the top, and have a high voltage pin inside and insulated from the inside enclosure. An electric field is produced between the pin and the inside enclosure. Air ions produced by collision with alpha particles inside the decay volume defined by the inside enclosure are attracted to the pin and the inner enclosure. With low alpha concentrations, individual alpha events can be measured to indicate the presence of radon or other alpha radiation. In another embodiment, an electrical field is produced between parallel plates which are insulated from a single decay cavity enclosure. 6 figs.

  1. 223. FREQUENTLY REPRODUCED VIEW OF GWMP SHOWING VARIABLE WIDTH MEDIANS ...

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

    223. FREQUENTLY REPRODUCED VIEW OF GWMP SHOWING VARIABLE WIDTH MEDIANS WITH INDEPENDENT ALIGNMENTS FROM KEY BRIDGE LOOKING NORTHWEST, 1953. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  2. Optical waveguide device with an adiabatically-varying width

    DOEpatents

    Watts; Michael R. , Nielson; Gregory N.

    2011-05-10

    Optical waveguide devices are disclosed which utilize an optical waveguide having a waveguide bend therein with a width that varies adiabatically between a minimum value and a maximum value of the width. One or more connecting members can be attached to the waveguide bend near the maximum value of the width thereof to support the waveguide bend or to supply electrical power to an impurity-doped region located within the waveguide bend near the maximum value of the width. The impurity-doped region can form an electrical heater or a semiconductor junction which can be activated with a voltage to provide a variable optical path length in the optical waveguide. The optical waveguide devices can be used to form a tunable interferometer (e.g. a Mach-Zehnder interferometer) which can be used for optical modulation or switching. The optical waveguide devices can also be used to form an optical delay line.

  3. Better Polynomial Algorithms on Graphs of Bounded Rank-Width

    NASA Astrophysics Data System (ADS)

    Ganian, Robert; Hliněný, Petr

    Although there exist many polynomial algorithms for NP-hard problems running on a bounded clique-width expression of the input graph, there exists only little comparable work on such algorithms for rank-width. We believe that one reason for this is the somewhat obscure and hard-to-grasp nature of rank-decompositions. Nevertheless, strong arguments for using the rank-width parameter have been given by recent formalisms independently developed by Courcelle and Kanté, by the authors, and by Bui-Xuan et al. This article focuses on designing formally clean and understandable "pseudopolynomial" (XP) algorithms solving "hard" problems (non-FPT) on graphs of bounded rank-width. Those include computing the chromatic number and polynomial or testing the Hamiltonicity of a graph and are extendable to many other problems.

  4. Tunable pulse width and multi-megawatt peak-power pulses from a nonlinearly compressed monolithic fiber MOPA system

    NASA Astrophysics Data System (ADS)

    Yamashita, Ryutarou; Maeda, Kazuo; Watanabe, Goro; Tei, Kazuyoku; Yamaguchi, Shigeru; Enokidani, Jun; Sumida, Shin

    2016-03-01

    We report on tunable pulse width and high peak power pulse generation from a nonlinearly compressed monolithic fiber MOPA system. The master seed source employs a Mach-Zehnder intensity modulator (MZIM). This seed source has operational flexibility with respect to pulse width, 90 ps to 2 ns and repetition rate, 200 kHz to 2 MHz. The seed pulses are amplified by a monolithic three-stage amplifier system based on polarization maintain Yb-doped fibers. The maximum output power was 32 W at the shortest pulse condition, the pulse width of 90 ps and the repetition rate of 750 kHz. A spectral width after amplification was broadened to 0.73 nm at RMS width. Both of ASE and SRS are not observed in the spectrum. After amplification, we also demonstrated pulse compression with a small piece of chirped volume Bragg-grating (CVBG) which has the dispersion rate of 81 ps/nm. As a result of pulse compression, the shortest pulse width was reduced from 90 ps to 3.5 ps, which brought an increase of the peak power up to 3.2 MW. The compressed pulses are clean with little structure in their wings. We can expand the operation range of the monolithic fiber MOPA system in pulse width, 3.5 ps to 2 ns.

  5. Patterns of river width and surface area newly revealed by the satellite-derived North American River Width (NARWidth) dataset

    NASA Astrophysics Data System (ADS)

    Allen, G. H.; Pavelsky, T.

    2014-12-01

    The total surface area of rivers and streams is a key quantity for estimating gaseous emissions from fluvial networks to the atmosphere. Presently, the most sophisticated evaluations of continental-scale river surface area rely on: 1) calculating river width from digital elevation models (DEMs) by scaling width to upstream drainage area via downstream hydraulic geometry (DHG) relationships; 2) extrapolating river width and length from large to small river basins using Horton ratios; and 3) extrapolating empirical relationships between climate and percentage water cover to from low- to high-latitude basins where hydrologically conditioned topographic data does not exist. Here we use the recently developed North American River Width (NARWidth) dataset to estimate the total surface area of North American rivers and streams. NARWidth is the first fine-resolution, continental-scale river centerline and width database. The database is derived from Landsat satellite imagery and contains measurements of >2.4×105 km of rivers wider than 30 m at mean annual discharge. We find that datasets that estimate river width by applying DHG relationships to DEMs underestimate the abundance of wide rivers and do not capture the widest rivers observed by NARWidth. We attribute these differences to: 1) the tendency of stream gauges to be located at stable, single channel sites, leading to a potential bias of measured river width relative to the representative river width throughout a river's entire length; and 2) physiographic conditions that are not captured by DHG and can cause substantial deviation from strict width-discharge relationships. We then calculate the total surface area of North American rivers by extrapolating the strong observed relationship between total river surface area and width at different widths (r2>0.996 for 100-2000 m widths) to narrow rivers and streams. We find that the total surface area of North American rivers is ~1.38×105 km2 for all rivers wider than 1

  6. Finite coplanar waveguide width effects in pulsed inductive microwave magnetometry

    SciTech Connect

    Schneider, M.L.; Kos, A.B.; Silva, T.J.

    2004-07-12

    The effect of finite coplanar waveguide (CPW) width on the measurement of the resonance frequency in thin ferromagnetic films has been characterized for pulsed inductive microwave magnetometry. A shift in resonant frequency is a linear function of the ratio of sample thickness to CPW width. The proportionality constant is experimentally determined to be 0.74{+-}0.1 times the saturation magnetization of the film. The frequency shift may be modeled as arising from an effective magnetic-anisotropy field.

  7. Quantifying River Widths of North America from Satellite Imagery

    NASA Astrophysics Data System (ADS)

    Allen, G. H.; Pavelsky, T.; Miller, Z.

    2013-12-01

    River width is a fundamental predictor variable in many hydrologic, geomorphic, and biogeochemical models, yet current large-scale models rely on theoretical hydraulic geometry relationships that do not fully capture natural variability in river form. Here we present the first high-resolution dataset of long-term mean width of North American rivers wider than 30 m. The dataset contains 7.93 million georeferenced width measurements derived from Landsat TM and ETM+ imagery that were acquired when rivers were most likely to be at mean discharge. We built the dataset by developing an automated procedure that selects and downloads raw imagery, creates cloud-free normalized difference water index images, histogram balances and mosaics them together, and produces a water mask using a dynamic water-land threshold technique. We then visually inspected and corrected the mask for errors and used RivWidth software to calculate river width at each river centerline pixel. We validated our dataset using >1000 United States Geological Survey and Water Survey of Canada in situ gauge station measurements. Error analysis shows a robust relationship between the remotely sensed widths and in situ gauge measurements with an r 2 = 0.86 (Spearman's = 0.81) and a mean absolute error of 27.5 m. We find that North American river widths lie on logarithmic frequency curve with some notable exceptions at widths <100 m. This dataset can be used to improve our understanding of the water, carbon, and nitrogen cycles, as well as large-scale landscape evolution models. Our results also allow for the characterization of the extent of rivers likely to be observable by the planned Surface Water and Ocean Topography (SWOT) satellite mission.

  8. Width of the plasmon resonance in metal clusters

    NASA Astrophysics Data System (ADS)

    Montag, B.; Reinhard, P.-G.

    1995-05-01

    The width of the plasmon resonance in the clusters Na+9, Na+21, and Na+41 is investigated in the framework of the structure-averaged jellium model and compared with recent experimental data. The two leading mechanisms for the line broadening are fragmentation of the resonance into nearby 1ph states and splitting through thermal quadrupole fluctuations. The fragmentation becomes activated mainly through octupole fluctuations and it gives the dominating contribution to the width.

  9. An H-alpha velocity study of S252

    NASA Technical Reports Server (NTRS)

    Fountain, W. F.; Gary, G. A.; Odell, C. R.

    1983-01-01

    The H II region S252 (NGC 2175) was studied by means of H-alpha radial velocities and line widths. The velocity structure appears to be dominated by the western ionization front, abutting a dense neutral cloud which is a CO source, and by symmetry abut the ionizing star. This data, together with other studies of CO, H167-alpha, and the H II radio continuum, allow construction of a model of S252. The H II model is basically a double blister formed by a luminous hot star being located between two orthogonal, elongated neutral clouds.

  10. Alpha-Decay Half-Lives of Superheavy Nuclei

    SciTech Connect

    Budaca, A. I.; Silisteanu, I.; Silisteanu, A. O.; Anghel, C. I.

    2010-11-24

    Half-lives given by self-consistent models for the {alpha}-clustering and resonance scattering are calculated and compared with data and empirical estimates. The major influence of the pairing, deformed shell closures and screening corrections is evidenced in the systematics of half-lives and provides a convenient basis for the interpretation of observed trends of the data and for prediction of new results. The very small widths of {alpha}-resonances observed experimentally in fusion-evaporation reactions, are interpreted as resonance levels of radioactive products, and such a correlation contributes directly to the study of the nuclear structure on the basis of decay data.

  11. The H-alpha/H-beta ratio in solar flares

    NASA Technical Reports Server (NTRS)

    Zirin, H.; Liggett, M.; Patterson, A.

    1982-01-01

    The present investigation involves the study of an extensive body of data accumulated of simultaneous H-alpha and H-beta cinematography of flares. The data were obtained with two telescopes simultaneously photographing flares in H-alpha and H-beta. The results of measurements in a number of flares are presented in a table. The flares were selected purely by optical quality of the data. That the measured ratios are not too different from those in stellar flares is suggested by the last two columns of the table. These columns show that a variety of possible line width ratios could give an integrated intensity ratio of less than unity.

  12. Crack width monitoring of concrete structures based on smart film

    NASA Astrophysics Data System (ADS)

    Zhang, Benniu; Wang, Shuliang; Li, Xingxing; Zhang, Xu; Yang, Guang; Qiu, Minfeng

    2014-04-01

    Due to its direct link to structural security, crack width is thought to be one of the most important parameters reflecting damage conditions of concrete structures. However, the width problem is difficult to solve with the existing structural health monitoring methods. In this paper, crack width monitoring by means of adhering enameled copper wires with different ultimate strains on the surface of structures is proposed, based on smart film crack monitoring put forward by the present authors. The basic idea of the proposed method is related to a proportional relationship between the crack width and ultimate strain of the broken wire. Namely, when a certain width of crack passes through the wire, some low ultimate strain wires will be broken and higher ultimate strain wires may stay non-broken until the crack extends to a larger scale. Detection of the copper wire condition as broken or non-broken may indicate the width of the structural crack. Thereafter, a multi-layered stress transfer model and specimen experiment are performed to quantify the relationship. A practical smart film is then redesigned with this idea and applied to Chongqing Jiangjin Yangtze River Bridge.

  13. The alpha channeling effect

    SciTech Connect

    Fisch, N. J.

    2015-12-10

    Alpha particles born through fusion reactions in a tokamak reactor tend to slow down on electrons, but that could take up to hundreds of milliseconds. Before that happens, the energy in these alpha particles can destabilize on collisionless timescales toroidal Alfven modes and other waves, in a way deleterious to energy confinement. However, it has been speculated that this energy might be instead be channeled into useful energy, so as to heat fuel ions or to drive current. Such a channeling needs to be catalyzed by waves Waves can produce diffusion in energy of the alpha particles in a way that is strictly coupled to diffusion in space. If these diffusion paths in energy-position space point from high energy in the center to low energy on the periphery, then alpha particles will be cooled while forced to the periphery. The energy from the alpha particles is absorbed by the wave. The amplified wave can then heat ions or drive current. This process or paradigm for extracting alpha particle energy collisionlessly has been called alpha channeling. While the effect is speculative, the upside potential for economical fusion is immense. The paradigm also operates more generally in other contexts of magnetically confined plasma.

  14. THE FUNDAMENTAL PLANE OF DAMPED Ly{alpha} SYSTEMS

    SciTech Connect

    Neeleman, Marcel; Wolfe, Arthur M.; Prochaska, J. Xavier

    2013-05-20

    Using a sample of 100 H I-selected damped Ly{alpha} (DLA) systems, observed with the High Resolution Echelle Spectrometer on the Keck I telescope, we present evidence that the scatter in the well-studied correlation between the redshift and metallicity of a DLA is largely due to the existence of a mass-metallicity relationship at each redshift. To describe the fundamental relations that exist between redshift, metallicity, and mass, we use a fundamental plane description, which is described by the following equation: [M/H] = (- 1.9 {+-} 0.5) + (0.74 {+-} 0.21) {center_dot} log {Delta}v{sub 90} - (0.32 {+-} 0.06) {center_dot} z. Here, we assert that the velocity width, {Delta}v{sub 90}, which is defined as the velocity interval containing 90% of the integrated optical depth, traces the mass of the underlying dark matter halo. This description provides two significant improvements over the individual descriptions of the mass-metallicity correlation and metallicity-redshift correlation. Firstly, the fundamental equation reduces the scatter around both relationships by about 20%, providing a more stringent constraint on numerical simulations modeling DLAs. Secondly, it confirms that the dark matter halos that host DLAs satisfy a mass-metallicity relationship at each redshift between redshifts 2 through 5.

  15. Enhancement of metastable zone width for solution growth of potassium acid phthalate

    NASA Astrophysics Data System (ADS)

    Srinivasan, K.; Meera, K.; Ramasamy, P.

    1999-09-01

    A new method has been developed in which the addition of a small amount of ethylenediamine tetra acetic acid (EDTA), a well-known chelating agent, enhances the metastable zone width significantly. Also, it has been found that this addition reduces the rate of nucleation and increases the growth rate of the crystal. This method has been employed for solution growth of potassium hydrogen phthalate (KC 8H 5O 4), which is also known as potassium acid phthalate (KAP).

  16. On the Assimilation of Tree-Ring-Width Chronologies

    NASA Astrophysics Data System (ADS)

    Acevedo, Walter; Reich, Sebastian; Cubasch, Ulrich

    2015-04-01

    Data assimilation (DA) of climate proxy records is currently acknowledged as a promising approach to the paleoclimate reconstruction problem, with the potential to bring physical consistency to reconstructed fields. Previous paleo-DA studies have typically assumed a linear relationship between climate forcing and the resulting proxy data, whereas there exist growing evidence of complex, potentially non-linear, proxy formation processes. Accordingly, it appears natural to simulate the proxy response to climate in a more realistic fashion, by way of proxy-specific forward models. Following this train of thought, we investigate the assimilation of the most traditional climate proxy type, Tree-Ring-Width (TRW) chronologies, using the process-based tree-ring growth forward model Vaganov-Shashkin-Lite (VSL) and ensemble Kalman filter (EnKF) techniques. Used as observation operator, VSL's formulation implies three compounding, challenging features: (i) time averaging, (ii) "switching recording" of 2 variables and (iii) bounded response windows leading to "thresholded response". DA experiments involving VSL-based pseudo-TRW observations are performed first for a chaotic 2-scale dynamical system, used as a cartoon of the atmosphere-land system, and then for an atmospheric general circulation model of intermediate complexity. Our results reveal that VSL's nonlinearities may considerable deteriorate the performance of EnKF for Time-Averaged (TA) estimation, as compared to the utilization of a TA linear observation operator. Moreover, we show that this assimilation skill loss can be considerably reduced by embedding VSL's formulation into fuzzy logic theory, which fosters new interpretations of tree-ring growth limitation processes.

  17. CT radiation profile width measurement using CR imaging plate raw data.

    PubMed

    Bjarnason, Thorarin Albert; Yang, Chang-Ying Joseph

    2015-01-01

    This technical note demonstrates computed tomography (CT) radiation profile measurement using computed radiography (CR) imaging plate raw data showing it is possible to perform the CT collimation width measurement using a single scan without saturating the imaging plate. Previously described methods require careful adjustments to the CR reader settings in order to avoid signal clipping in the CR processed image. CT radiation profile measurements were taken as part of routine quality control on 14 CT scanners from four vendors. CR cassettes were placed on the CT scanner bed, raised to isocenter, and leveled. Axial scans were taken at all available collimations, advancing the cassette for each scan. The CR plates were processed and raw CR data were analyzed using MATLAB scripts to measure collimation widths. The raw data approach was compared with previously established methodology. The quality control analysis scripts are released as open source using creative commons licensing. A log-linear relationship was found between raw pixel value and air kerma, and raw data collimation width measurements were in agreement with CR-processed, bit-reduced data, using previously described methodology. The raw data approach, with intrinsically wider dynamic range, allows improved measurement flexibility and precision. As a result, we demonstrate a methodology for CT collimation width measurements using a single CT scan and without the need for CR scanning parameter adjustments which is more convenient for routine quality control work. PMID:26699559

  18. Effect of Channel Length and Width on NBTI in Ultra Deep Sub-Micron PMOSFETs

    NASA Astrophysics Data System (ADS)

    Cao, Yan-Rong; Ma, Xiao-Hua; Hao, Yue; Tian, Wen-Chao

    2010-03-01

    The effects of channel length and width on the degradation of negative bias temperature instability (NBTI) are studied. With the channel length decreasing, the NBTI degradation increases. As the channel edges have more damage and latent damage for the process reasons, the device can be divided into three parts: the gate and source overlap region, the middle channel region, and the gate and drain overlap region. When the NBTI stress is applied, the non-uniform distribution of the generated defects in the three parts will be generated due to the inhomogeneous degradation. With the decreasing channel length, the channel edge regions will take up a larger ratio to the middle channel region and the degradation of NBTI is enhanced. The channel width also plays an important role in the degradation of NBTI. There is an inflection point during the decreasing channel width. There are two particular factors: the lower vertical electric field effect for the thicker gate oxide thickness of the shallow trench isolation (STI) edge and the STI mechanical stress effecting on the NBTI degradation. The former reduces and the latter intensifies the degradation. Under the mutual compromise of the both factors, when the effect of the STI mechanical stress starts to prevail over the lower vertical electric field effect with the channel width decreasing, the inflection point comes into being.

  19. Giant dipole resonance width in nuclei near Sn at low temperature and high angular momentum

    SciTech Connect

    Bhattacharya, Srijit; Mukhopadhyay, S.; Pandit, Deepak; Pal, Surajit; Bhattacharya, S.; Bhattacharya, C.; Banerjee, K.; Kundu, S.; Rana, T. K.; Dey, A.; Mukherjee, G.; Ghosh, T.; Gupta, D.; Banerjee, S. R.

    2008-02-15

    High energy {gamma} rays in coincidence with low energy yrast {gamma} rays have been measured from {sup 113}Sb, at excitation energies of 109 and 122 MeV, formed by bombarding {sup 20}Ne on {sup 93}Nb at projectile energies of 145 and 160 MeV, respectively, to study the role of angular momentum (J) and temperature (T) over giant dipole resonance (GDR) width ({gamma}). The maximum populated angular momenta for fusion were 67({Dirac_h}/2{pi}) and 73({Dirac_h}/2{pi}), respectively, for the above-mentioned beam energies. The high energy photons were detected using a Large Area Modular BaF{sub 2} Detector Array (LAMBDA) along with a 24-element multiplicity filter. After pre-equilibrium corrections, the excitation energy E* was averaged over the decay steps of the compound nucleus (CN). The average values of temperature, angular momentum, CN mass, etc., have been calculated using the statistical model code CASCADE. Using those average values, results show the systematic increase of GDR width with T, which is consistent with Kusnezov parametrization and the thermal shape fluctuation model (TSFM). The rise of GDR width with temperature also supports the assumptions of adiabatic coupling in the TSFM. But the GDR widths and corresponding reduced plots with J are not consistent with those of the theoretical model at high spins.

  20. Reliability of the Tran-Blaha functional in predicting band gaps and widths

    NASA Astrophysics Data System (ADS)

    Rignanese, Gian-Marco; David, Waroquiers; Lherbier, Aurélien; Miglio, Anna; Stankovski, Martin; Ponce, Samuel; Oliveira, Micael; Giantomassi, Matteo; Gonze, Xavier

    2013-03-01

    For a set of oxides and semiconductors, we compute the electronic band structures (gaps and widths) within Density-Functional theory (DFT) using the Tran-Blaha (TB09) functional [Phys. Rev. Lett. 102, 226401 (2009)]. We compare them with those obtained from (i) DFT using the local-density approximation (LDA), (ii) many-body perturbation theory (MBPT), and (iii) experiments. TB09 leads to band gaps in much better agreement with experiment than the LDA. However, the valence (and conduction) band widths are often underestimated (noticeably more than in LDA). MBPT corrections are obtained peforming one-shot GW calculations using DFT eigenenergies and wavefunctions as starting point (both LDA and TB09 are considered). These corrections lead to a much better agreement with experimental data for the band widths. The MBPT band gaps obtained starting TB09 are close to those from quasi-particle self-consistent GW calculations, at a much reduced cost. Finally, we explore the possibility to tune a semi-empirical parameter present in the TB09 functional aiming to obtain simultaneously better gaps and band widths. We find that these requirements are conflicting.

  1. Giant dipole resonance width in nuclei near Sn at low temperature and high angular momentum

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Srijit; Mukhopadhyay, S.; Pandit, Deepak; Pal, Surajit; de, A.; Bhattacharya, S.; Bhattacharya, C.; Banerjee, K.; Kundu, S.; Rana, T. K.; Dey, A.; Mukherjee, G.; Ghosh, T.; Gupta, D.; Banerjee, S. R.

    2008-02-01

    High energy γ rays in coincidence with low energy yrast γ rays have been measured from Sb113, at excitation energies of 109 and 122 MeV, formed by bombarding Ne20 on Nb93 at projectile energies of 145 and 160 MeV, respectively, to study the role of angular momentum (J) and temperature (T) over giant dipole resonance (GDR) width (Γ). The maximum populated angular momenta for fusion were 67ℏ and 73ℏ, respectively, for the above-mentioned beam energies. The high energy photons were detected using a Large Area Modular BaF2 Detector Array (LAMBDA) along with a 24-element multiplicity filter. After pre-equilibrium corrections, the excitation energy E* was averaged over the decay steps of the compound nucleus (CN). The average values of temperature, angular momentum, CN mass, etc., have been calculated using the statistical model code CASCADE. Using those average values, results show the systematic increase of GDR width with T, which is consistent with Kusnezov parametrization and the thermal shape fluctuation model (TSFM). The rise of GDR width with temperature also supports the assumptions of adiabatic coupling in the TSFM. But the GDR widths and corresponding reduced plots with J are not consistent with those of the theoretical model at high spins.

  2. Precision Measurement of {eta} --> {gamma} {gamma} Decay Width via the Primakoff Effect

    SciTech Connect

    Gan, Liping Gin

    2013-08-01

    A precision measurement of the {eta} --> {gamma} {gamma} decay width via the Primakoff effect is underway in Hall D at Jefferson Lab. The decay width will be extracted from measured differential cross sections at forward angles on two light targets, liquid hydrogen and 4He, using a 11.5 GeV tagged photon beam. Results of this experiment will not only potentially resolve a long standing discrepancy between the Primakoff and the collider measurements, but will also reduce the experimental uncertainty by a factor of two on the average value of previous experimental results listed by the Particle Data Group(PDG). It will directly improve all other eta partial decay widths which rely on the accuracy of the eta radiative decay width. The projected 3% precision on the {Gamma}({eta} --> {gamma} {gamma} ) measurement will have a significant impact on the experimental determination of the fundamental parameters in QCD, such as the ratio of light quark masses (m{sub u},m{sub d},m{sub s}) and the {eta} - {eta}' mixing angle. It will be a sensitive probe for understanding QCD symmetries and the origin and the dynamics of QCD symmetry breaking.

  3. Patterns of river width and surface area revealed by the satellite-derived North American River Width data set

    NASA Astrophysics Data System (ADS)

    Allen, George H.; Pavelsky, Tamlin M.

    2015-01-01

    hydraulic, hydrologic, and biogeochemical models evolve toward greater spatial resolution and larger extent, robust morphometric data sets are essential to constrain their results. Here we present the Landsat-derived North American River Width (NARWidth) data set, the first fine-resolution, continental scale river centerline and width database. NARWidth contains measurements of >2.4 × 105 km of rivers wider than 30 m at mean annual discharge. We find that conventional digital elevation model-derived width data sets underestimate the abundance of wide rivers. To calculate the total surface area of North American rivers, we extrapolate the strong observed relationship between river width and total surface area at different river widths (r2 > 0.99 for 100-2000 m widths) to narrower rivers and streams. We conservatively estimate the total surface area of North American rivers as 1.24-0.15+0.39 × 105 km2 (1σ confidence intervals), values 20-15+38% greater than previous estimates used to evaluate greenhouse gas efflux from rivers to the atmosphere.

  4. The relationship between innercanthal dimension and interalar width to the intercanine width of maxillary anterior teeth in central Indian population

    PubMed Central

    Deogade, Suryakant Chhagan; Mantri, Sneha S.; Sumathi, K.; Rajoriya, Shivani

    2015-01-01

    Statement of Problem: Selection of proper sized maxillary anterior teeth is one of the difficult clinical steps in complete denture esthetics. Several studies have been reported to establish methods of estimating the combined width of maxillary anterior teeth. Purpose: The aim of this study was to determine whether a relationship exists between the innercanthal distance (ICD) and interalar width (IAW) with the combined width of maxillary anterior teeth. Material and Methods: The maxillary anterior teeth of 600 adult subjects were examined. ICD was measured between the median angles of the palpebral fissure. IAW was measured between the ala of the nose at their widest point. The mean combined width of the maxillary anterior teeth was determined intraorally at their widest dimension. Pearson's correlation coefficients were calculated to determine the relationship between ICD, IAW and the combined width of maxillary anterior teeth (α =0.05). Results: Although the Pearson correlation coefficients were relatively small, a significant relationship existed between innercanthal dimension and IAW (P < 0001). Conclusion: Within the limitations of this study, the results suggest that ICD and IAW cannot be used as a preliminary method for determining the width of the maxillary anterior teeth for edentulous patients. PMID:26929493

  5. Alpha Particle Diagnostic

    SciTech Connect

    Fisher, Ray, K.

    2009-05-13

    The study of burning plasmas is the next frontier in fusion energy research, and will be a major objective of the U.S. fusion program through U.S. collaboration with our international partners on the ITER Project. For DT magnetic fusion to be useful for energy production, it is essential that the energetic alpha particles produced by the fusion reactions be confined long enough to deposit a significant fraction of their initial ~3.5 MeV energy in the plasma before they are lost. Development of diagnostics to study the behavior of energetic confined alpha particles is a very important if not essential part of burning plasma research. Despite the clear need for these measurements, development of diagnostics to study confined the fast confined alphas to date has proven extremely difficult, and the available techniques remain for the most part unproven and with significant uncertainties. Research under this grant had the goal of developing diagnostics of fast confined alphas, primarily based on measurements of the neutron and ion tails resulting from alpha particle knock-on collisions with the plasma deuterium and tritium fuel ions. One of the strengths of this approach is the ability to measure the alphas in the hot plasma core where the interesting ignition physics will occur.

  6. The width of gamma-ray burst spectra

    NASA Astrophysics Data System (ADS)

    Axelsson, Magnus; Borgonovo, Luis

    2015-03-01

    The emission processes active in the highly relativistic jets of gamma-ray bursts (GRBs) remain unknown. In this paper, we propose a new measure to describe spectra: the width of the EFE spectrum, a quantity dependent only on finding a good fit to the data. We apply this to the full sample of GRBs observed by Fermi/Gamma-ray Burst Monitor (GBM) and Compton Gamma-ray Observatory/Burst and Transient Source Experiment (BATSE). The results from the two instruments are fully consistent. We find that the median widths of spectra from long and short GRBs are significantly different (chance probability <10-6). The width does not correlate with either duration or hardness, and this is thus a new, independent distinction between the two classes. Comparing the measured spectra with widths of spectra from fundamental emission processes - synchrotron and blackbody radiation - the results indicate that a large fraction of GRB spectra are too narrow to be explained by synchrotron radiation from a distribution of electron energies: for example, 78 per cent of long GRBs and 85 per cent of short GRBs are incompatible with the minimum width of standard slow cooling synchrotron emission from a Maxwellian distribution of electrons, with fast cooling spectra predicting even wider spectra. Photospheric emission can explain the spectra if mechanisms are invoked to give a spectrum much broader than a blackbody.

  7. Capacitor charging FET switcher with controller to adjust pulse width

    DOEpatents

    Mihalka, Alex M.

    1986-01-01

    A switching power supply includes an FET full bridge, a controller to drive the FETs, a programmable controller to dynamically control final output current by adjusting pulse width, and a variety of protective systems, including an overcurrent latch for current control. Power MOSFETS are switched at a variable frequency from 20-50 kHz to charge a capacitor load from 0 to 6 kV. A ferrite transformer steps up the DC input. The transformer primary is a full bridge configuration with the FET switches and the secondary is fed into a high voltage full wave rectifier whose output is connected directly to the energy storage capacitor. The peak current is held constant by varying the pulse width using predetermined timing resistors and counting pulses. The pulse width is increased as the capacitor charges to maintain peak current. A digital ripple counter counts pulses, and after the desired number is reached, an up-counter is clocked. The up-counter output is decoded to choose among different resistors used to discharge a timing capacitor, thereby determining the pulse width. A current latch shuts down the supply on overcurrent due to either excessive pulse width causing transformer saturation or a major bridge fault, i.e., FET or transformer failure, or failure of the drive circuitry.

  8. Surface roughness from MOLA backscatter pulse-widths

    NASA Astrophysics Data System (ADS)

    Poole, W. D.; Muller, J.-P.; Gupta, S.; Grindrod, P. M.

    2013-09-01

    The time-spread of backscatter laser altimeter pulses, known as pulse-widths, are thought to be capable of being used to infer variations in topography within the footprint of the laser pulse. Here, Mars Orbiter Laser Altimeter (MOLA) pulse-widths have been compared to surface roughness and slope, as measured from high-resolution digital terrain models (DTMs), over different terrains in order to understand how this dataset can be used in the selection of landing and roving sites, and in inferring surface formation and evolution. The results are varied, and suggest that pulsewidths do not respond consistently to variations in terrain. The results show that over Mars Science Laboratory (MSL) candidate landing sites, the pulse-widths can be used as a rough estimate of surface roughness at baselines much larger than the footprint of the pulse. Over much rougher terrain, these pulse-widths respond best to footprint scale slope, which suggests that an additional slope correction for 75 m baselines slopes is required to infer finer scale roughness. However, this is shown not to be the case, as correcting the pulse-widths for 75 m slopes at the MSL candidate sites, and detrending the DTM data, produced poorer results.

  9. Rapid inspection for sub-wavelength line-width

    NASA Astrophysics Data System (ADS)

    Chang, Ming; Chen, Chih-Yang; Liou, Huay-Chung

    2010-08-01

    This paper presents a rapid inspection technique used for the evaluation of structures with line-width below sub-wavelength and diffraction limit. Inspections are carried out with an optical microscope via a vertical scanning and through-focus measurement, where the intensities of reflection light from different focal positions of the specimen are transferred into a series of numeric data through the use of an Entropy algorithm. A through-focus focus metric (TFFM) profile is then obtained for the inspection of line-width. The secondary peak in TFFM profile is related to the distance of 180° phase difference of the grating image according to the Talbot effect. This characteristic can be used to determine the pitch of grating specimen. Based on the variance of the secondary peak for different line-width, the line-width of a grating can be obtained from the comparison of simulated and measured data. Experimental results show that the Entropy algorithm can be used to achieve more reliable and fast evaluation in line-width inspection. Furthermore, as through-focus measurement is a non-destructive inspection method, it can be used as another positive element which equals to a traditional nano-scale inspection methods, such as AFM and SEM.

  10. Effective Widths of Compression-Loaded Plates With a Cutout

    NASA Technical Reports Server (NTRS)

    Hilburger, Mark W.; Nemeth, Michael P.; Starnes, James H., Jr.

    2000-01-01

    A study of the effects of cutouts and laminate construction on the prebuckling and initial postbuckling stiffnesses, and the effective widths of compression-loaded, laminated-composite and aluminum square plates is presented. The effective-width concept is extended to plates with cutouts, and experimental and nonlinear finite-element analysis results are presented. Behavioral trends are compared for seven plate families and for cutout-diameter-to-plate-width ratios up to 0.66. A general compact design curve that can be used to present and compare the effective widths for a wide range of laminate constructions is also presented. A discussion of how the results can be used and extended to include certain types of damage, cracks, and other structural discontinuities or details is given. Several behavioral trends are described that initially appear to be nonintuitive. The results demonstrate a complex interaction between cutout size and plate orthotropy that affects the axial stiffness and effective width of a plate subjected to compression loads.

  11. Optimized mixture of hops rho iso-alpha acids-rich extract and acacia proanthocyanidins-rich extract reduces insulin resistance in 3T3-L1 adipocytes and improves glucose and insulin control in db/db mice

    PubMed Central

    Darland, Gary; Konda, Veera Reddy; Pacioretty, Linda M.; Chang, Jyh-Lurn; Bland, Jeffrey S.; Babish, John G.

    2012-01-01

    Rho iso-alpha acids-rich extract (RIAA) from Humulus lupulus (hops) and proanthocyanidins-rich extracts (PAC) from Acacia nilotica exert anti-inflammatory and anti-diabetic activity in vitro and in vivo. We hypothesized that a combination of these two extracts would exert enhanced effects in vitro on inflammatory markers and insulin signaling, and on nonfasting glucose and insulin in db/db mice. Over 49 tested combinations, RIAA:PAC at 5:1 (6.25 µg/mL) exhibited the greatest reductions in TNFα-stimulated lipolysis and IL-6 release in 3T3-L1 adipocytes, comparable to 5 µg/mL troglitazone. Pretreatment of 3T3-L1 adipocytes with this combination (5 µg/mL) also led to a 3-fold increase in insulin-stimulated glucose uptake that was comparable to 5 µg/mL pioglitazone or 901 µg/mL aspirin. Finally, db/db mice fed with RIAA:PAC at 5:1 (100 mg/kg) for 7 days resulted in 22% decrease in nonfasting glucose and 19% decrease in insulin that was comparable to 0.5 mg/kg rosiglitazone and better than 100 mg/kg metformin. RIAA:PAC mixture may have the potential to be an alternative when conventional therapy is undesirable or ineffective, and future research exploring its long-term clinical application is warranted. PMID:23198019

  12. Bilocal expansion of the Borel amplitude and the hadronic tau decay width

    SciTech Connect

    Cvetic, Gorazd; Lee, Taekoon

    2001-07-01

    The singular part of the Borel transform of a QCD amplitude near the infrared renormalon can be expanded in terms of higher order Wilson coefficients of the operators associated with the renormalon. In this paper we observe that this expansion gives nontrivial constraints on the Borel amplitude that can be used to improve the accuracy of the ordinary perturbative expansion of the Borel amplitude. In particular, we consider the Borel transform of the Adler function and its expansion around the first infrared renormalon due to the gluon condensate. Using the next-to-leading order (NLO) Wilson coefficient of the gluon condensate operator, we obtain an exact constraint on the Borel amplitude at the first IR renormalon. We then extrapolate, using judiciously chosen conformal transformations and Pade{prime} approximants, the ordinary perturbative expansion of the Borel amplitude in such a way that this constraint is satisfied. This procedure allows us to predict the O({alpha}{sub s}{sup 4}) coefficient of the Adler function, which gives a result consistent with the estimate by Kataev and Starshenko using a completely different method. We then apply this improved Borel amplitude to the tau decay width and obtain the strong coupling constant {alpha}{sub s}(M{sub z}{sup 2})=0.1193{+-}0.0007{sub exp.}{+-}0.0010{sub EW+CKM}{+-}0.0009{sub meth.}{+-}0.0003{sub evol.}. We then compare this result with those of other resummation methods.

  13. Morphodynamics structures induced by variations of the channel width

    NASA Astrophysics Data System (ADS)

    Duro, Gonzalo; Crosato, Alessandra; Tassi, Pablo

    2014-05-01

    In alluvial channels, forcing effects, such as a longitudinally varying width, can induce the formation of steady bars (Olesen, 1984). The type of bars that form, such as alternate, central or multiple, will mainly depend on the local flow width-to-depth ratio and on upstream conditions (Struiksma et al., 1985). The effects on bar formation of varying the channel width received attention only recently and investigations, based on flume experiments and mathematical modelling, are mostly restricted to small longitudinal sinusoidal variations of the channel width (e.g. Repetto et al., 2002; Wu and Yeh, 2005, Zolezzi et al., 2012; Frascati and Lanzoni, 2013). In this work, we analyze the variations in equilibrium bed topography in a longitudinal width-varying channel with characteristic scales of the Waal River (The Netherlands) using two different 2D depth-averaged morphodynamic models, one based on the Delft3D code and one on Telemac-Mascaret system. In particular, we explore the effects of changing the wavelength of sinusoidal width variations in a straight channel, focusing on the effects of the spatial lag between bar formation and forcing that is observed in numerical models and laboratory experiments (e.g. Crosato et al, 2011). We extend the investigations to finite width variations in which longitudinal changes of the width-to-depth ratio are such that they may affect the type of bars that become unstable (alternate, central or multiple bars). Numerical results are qualitatively validated with field observations and the resulting morphodynamic pattern is compared with the physics-based predictor of river bar modes by Crosato and Mosselman (2009). The numerical models are finally used to analyse the experimental conditions of Wu and Yeh (2005). The study should be seen as merely exploratory. The aim is to investigate possible approaches for future research aiming at assessing the effects of artificial river widening and narrowing to control bar formation in

  14. PACCE: Perl Algorithm to Compute Continuum and Equivalent Widths

    NASA Astrophysics Data System (ADS)

    Riffel, Rogério; Borges Vale, Tibério

    2011-05-01

    We present Perl Algorithm to Compute continuum and Equivalent Widths (pacce). We describe the methods used in the computations and the requirements for its usage. We compare the measurements made with pacce and "manual" ones made using iraf splot task. These tests show that for SSP models the equivalent widths strengths are very similar (differences <0.2A) for both measurements. In real stellar spectra, the correlation between both values is still very good, but with differences of up to 0.5A. pacce is also able to determine mean continuum and continuum at line center values, which are helpful in stellar population studies. In addition, it is also able to compute the uncertainties in the equivalent widths using photon statistics.

  15. Interatomic Coulombic decay widths of helium trimer: Ab initio calculations

    SciTech Connect

    Kolorenč, Přemysl; Sisourat, Nicolas

    2015-12-14

    We report on an extensive study of interatomic Coulombic decay (ICD) widths in helium trimer computed using a fully ab initio method based on the Fano theory of resonances. Algebraic diagrammatic construction for one-particle Green’s function is utilized for the solution of the many-electron problem. An advanced and universal approach to partitioning of the configuration space into discrete states and continuum subspaces is described and employed. Total decay widths are presented for all ICD-active states of the trimer characterized by one-site ionization and additional excitation of an electron into the second shell. Selected partial decay widths are analyzed in detail, showing how three-body effects can qualitatively change the character of certain relaxation transitions. Previously unreported type of three-electron decay processes is identified in one class of the metastable states.

  16. Interatomic Coulombic decay widths of helium trimer: Ab initio calculations.

    PubMed

    Kolorenč, Přemysl; Sisourat, Nicolas

    2015-12-14

    We report on an extensive study of interatomic Coulombic decay (ICD) widths in helium trimer computed using a fully ab initio method based on the Fano theory of resonances. Algebraic diagrammatic construction for one-particle Green's function is utilized for the solution of the many-electron problem. An advanced and universal approach to partitioning of the configuration space into discrete states and continuum subspaces is described and employed. Total decay widths are presented for all ICD-active states of the trimer characterized by one-site ionization and additional excitation of an electron into the second shell. Selected partial decay widths are analyzed in detail, showing how three-body effects can qualitatively change the character of certain relaxation transitions. Previously unreported type of three-electron decay processes is identified in one class of the metastable states. PMID:26671378

  17. Autoionization widths by Stieltjes imaging applied to Lanczos pseudospectra

    SciTech Connect

    Kopelke, S.; Gokhberg, K.; Cederbaum, L. S.; Tarantelli, F.; Averbukh, V.

    2011-01-14

    Excited states of atoms and molecules lying above the ionization threshold can decay by electron emission in a process commonly known as autoionization. The autoionization widths can be calculated conveniently using Fano formalism and discretized atomic and molecular spectra by a standard procedure referred to as Stieltjes imaging. The Stieltjes imaging procedure requires the use of the full discretized spectrum of the final states of the autoionization, making its use for poly-atomic systems described by high-quality basis sets impractical. Following our previous work on photoionization cross-sections, here we show that also in the case of autoionization widths, the full diagonalization bottleneck can be overcome by the use of Lanczos pseudospectra. We test the proposed method by calculating the well-documented autoionization widths of inner-valence-excited neon and apply the new technique to autoionizing states of hydrofluoric acid and benzene.

  18. Numerical simulation for influence of pulse width on the temperature field of unidirectional carbon fiber

    NASA Astrophysics Data System (ADS)

    Yuan, Boshi; Jin, Guangyong; Wei, Zhi; Wang, Di; Ma, Yao

    2014-12-01

    The unidirectional carbon fiber material is commonly used in the Carbon Fiber Reinforced Plastics (CFRP). The COMSOL Multiphysics finite element analysis software was utilized in this paper. And the 3D anisotropy model, which based on heat conduction equation, was established to simulate the temperature field of the carbon fiber irradiated by pulse laser. The research focused on the influences of the laser width on the material temperature field. The thermal analysis results indicated that during the process of irradiation, the temperature field distribution of the carbon fiber was different from the distribution of laser spot on the surface. The incident laser is Gauss laser, but the temperature field distribution presented oval. It resulted from the heat transfer coefficient of carbon fiber was different in the axial and in the radial. The temperature passed along the fiber axial faster than the radial. Under the condition of the laser energy density constant, and during the laser irradiation time, the depth of the carbon fiber temperature field increased with the pulse width increasing, and the area of the carbon fiber temperature field increased with the pulse width increasing, However, the temperature of the laser irradiated center showed a trend of decrease with the increasing of pulse width. The results showed that when the laser affection was constant, the laser energy affected on the carbon fiber per unit time was increased with the decrease of the pulse width. Due to the limits of the heat transfer coefficient of the material and laser irradiation time, the energy was injected in carbon fiber within a short time. With the reducing of the heat conduction area, the depth and the area of the temperature field would be also decreased. With the increase of pulse width, the time of energy injected in carbon fiber was increased, and the laser energy affected on the carbon fiber per unit time was decrease. With the heat conduction area increasing, the depth and

  19. The astrophysical reaction rate for the {sup 18}F(p,{alpha}){sup 15}O reaction

    SciTech Connect

    Rehm, K.E.; Paul, M.; Roberts, A.D.

    1996-03-01

    Proton and alpha widths for a 3/2{sup +} ({ell}{sub p} = 0) state in {sup 19}Ne at E{sub x} = 7.1 MeV have been extracted using the results of recent measurements of the {sup 18}F(p,{alpha}){sup 15}O reaction. This {ell}{sub p} = 0 resonance dominates the astrophysical reaction rates at temperatures T{sub 9} > 0.5.

  20. Width effects in transonic flow over a rectangular cavity

    DOE PAGESBeta

    Beresh, Steven J.; Wagner, Justin L.; Henfling, John F.; Spillers, Russell Wayne; Pruett, Brian Owen Matthew

    2015-07-24

    A previous experiment by the present authors studied the flow over a finite-width rectangular cavity at freestream Mach numbers 1.5–2.5. In addition, this investigation considered the influence of three-dimensional geometry that is not replicated by simplified cavities that extend across the entire wind-tunnel test section. The latter configurations have the attraction of easy optical access into the depths of the cavity, but they do not reproduce effects upon the turbulent structures and acoustic modes due to the length-to-width ratio, which is becoming recognized as an important parameter describing the nature of the flow within narrower cavities.

  1. Domain wall width of lithium niobate poled during growth

    NASA Astrophysics Data System (ADS)

    Brooks, R.; Townsend, P. D.; Hole, D. E.; Callejo, D.; Bermúdez, V.; Diéguez, E.

    2003-04-01

    Good quality crystals of periodically poled lithium niobate can be generated directly during growth. However, the temperature gradients at the zone boundaries define the width of the regions where the polarity is reversed. Hence, the region influenced the domain transition may be a significant fraction of the overall poling period for material poled during growth. Evidence for the scale of this feature is reported both by chemical etching and by the less common method of ion beam luminescence and the `domain wall' width approximately 1 mum for these analyses. The influence of the reversal region may differ for alternative techniques but the relevance to device design for second harmonic generation is noted.

  2. Fjords in viscous fingering: selection of width and opening scale

    SciTech Connect

    Mineev-weinstein, Mark; Ristroph, Leif; Thrasher, Matthew; Swinney, Harry

    2008-01-01

    Our experiments on viscous fingering of air into oil contained between closely spaced plates reveal two selection rules for the fjords of oil that separate fingers of air. (Fjords are the building blocks of solutions of the zero-surface-tension Laplacian growth equation.) Experiments in rectangular and circular geometries yield fjords with base widths {lambda}{sub c}/2, where {lambda}{sub c} is the most unstable wavelength from a linear stability analysis. Further, fjords open at an angle of 8.0{sup o}{+-}1.0{sup o}. These selection rules hold for a wide range of pumping rates and fjord lengths, widths, and directions.

  3. Automated width measurements of Martian dust devil tracks

    NASA Astrophysics Data System (ADS)

    Statella, Thiago; Pina, Pedro; da Silva, Erivaldo Antônio

    2016-03-01

    Studying dust devils is important to better understand Mars climate and resurfacing phenomena. This paper presents an automated approach to calculate the width of tracks in orbital images. The method is based on Mathematical Morphology and was applied to a set of 200 HiRISE and MOC images of five Mars quadrangles, which were Aeolis, Argyre, Noachis, Hellas and Eridania. Information obtained by our method was compared with results of manual analysis performed by other authors. In addition, we show that track widths do not follow a normal distribution.

  4. THE HETDEX PILOT SURVEY. II. THE EVOLUTION OF THE Ly{alpha} ESCAPE FRACTION FROM THE ULTRAVIOLET SLOPE AND LUMINOSITY FUNCTION OF 1.9 < z < 3.8 LAEs

    SciTech Connect

    Blanc, Guillermo A.; Adams, Joshua J.; Gebhardt, Karl; Hao Lei; Fry, Alexander B.; Jeong, Donghui; Komatsu, Eiichiro; Murphy, Jeremy D.; Hill, Gary J.; Drory, Niv; Bender, Ralf; Hopp, Ulrich; Kelzenberg, Ralf; Ciardullo, Robin; Gronwall, Caryl; Schneider, Donald P.; Finkelstein, Steven L.; Gawiser, Eric; MacQueen, Phillip; Roth, Martin M.

    2011-07-20

    We study the escape of Ly{alpha} photons from Ly{alpha} emitting galaxies (LAEs) and the overall galaxy population using a sample of 99 LAEs at 1.9 < z < 3.8 detected through integral-field spectroscopy of blank fields by The Hobby Eberly Telescope Dark Energy Experiment Pilot Survey. For 89 LAEs with broadband counterparts we measure ultraviolet (UV) luminosities and UV slopes, and estimate E(B - V) under the assumption of a constant intrinsic UV slope for LAEs. These quantities are used to estimate dust-corrected star formation rates (SFRs). Comparison between the observed Ly{alpha} luminosity and that predicted by the dust-corrected SFR yields the Ly{alpha} escape fraction. We also measure the Ly{alpha} luminosity function and luminosity density ({rho}{sub Ly{alpha}}) at 2 < z < 4. Using this and other measurements from the literature at 0.3 < z < 7.7 we trace the redshift evolution of {rho}{sub Ly{alpha}.} We compare it to the expectations from the star formation history of the universe and characterize the evolution of the Ly{alpha} escape fraction of galaxies. LAEs at 2 < z < 4 selected down to a luminosity limit of L(Ly{alpha}) > (3-6) x 10{sup 42} erg s{sup -1} (0.25-0.5 L*), have a mean (E(B - V)) = 0.13 {+-} 0.01, implying an attenuation of {approx}70% in the UV. They show a median UV uncorrected SFR = 11 M{sub sun} yr{sup -1}, dust-corrected SFR = 34 M{sub sun} yr{sup -1}, and Ly{alpha} equivalent widths (EWs) which are consistent with normal stellar populations. We measure a median Ly{alpha} escape fraction of 29%, with a large scatter and values ranging from a few percent to 100%. The Ly{alpha} escape fraction in LAEs correlates with E(B - V) in a way that is expected if Ly{alpha} photons suffer from similar amounts of dust extinction as UV continuum photons. This result implies that a strong enhancement of the Ly{alpha} EW with dust, due to a clumpy multi-phase interstellar medium (ISM), is not a common process in LAEs at these redshifts. It also

  5. All-electronic line width reduction in a semiconductor diode laser using a crystalline microresonator

    NASA Astrophysics Data System (ADS)

    Rury, Aaron S.; Mansour, Kamjou; Yu, Nan

    2015-07-01

    This study examines the capability to significantly suppress the frequency noise of a semiconductor distributed feedback diode laser using a universally applicable approach: a combination of a high-Q crystalline whispering gallery mode microresonator reference and the Pound-Drever-Hall locking scheme using an all-electronic servo loop. An out-of-loop delayed self-heterodyne measurement system demonstrates the ability of this approach to reduce a test laser's absolute line width by nearly a factor of 100. In addition, in-loop characterization of the laser stabilized using this method demonstrates a 1-kHz residual line width with reference to the resonator frequency. Based on these results, we propose that utilization of an all-electronic loop combined with the use of the wide transparency window of crystalline materials enable this approach to be readily applicable to diode lasers emitting in other regions of the electromagnetic spectrum, especially in the UV and mid-IR.

  6. Line width tuning and smoothening for periodical grating fabrication in nanoimprint lithography

    NASA Astrophysics Data System (ADS)

    Yao, Yuhan; Wang, Yifei; Liu, He; Li, Yuanrui; Song, Boxiang; Wu, Wei

    2015-11-01

    Nanoimprint lithography is a promising technology for patterning large-area structures in nanometer scale at a low cost. In order to fabricate large-area nanoimprint master mold, interference lithography is widely used in defining periodical structures. However, neither roughness nor structural dimension can be effectively controlled via interference exposure. In this paper, we report a fabrication technique based on V-shaped master mold that can adjust line width of gratings as well as reduce the sidewall roughness. The fabrication of the V-shaped grating master mold is demonstrated, and the line width tuning and smoothening processes are discussed. With the help of the smoothening process, the optical efficiency of smoothened guided-mode resonance grating increased by 75 % from the original sample.

  7. Curium-244 alpha-sources for space research

    PubMed

    Radchenko; Andreichikov; Wanke; Gavrilo; Korchuganov; Rieder; Ryabinin; Economou

    2000-10-01

    Special alpha-proton-X-ray spectrometric complexes (APXS) have been developed in order to perform chemical analyses of the Mars atmosphere and rock surface compounds by alpha back-scattering, alpha-proton measurements, and X-ray fluorescence. The sources were prepared by high temperature condensation of metal curium vapour onto silicon substrates. They are silicon disks with curium-244 fixed on their surfaces as a silicide. The sources have overall dimensions as follows: disk diameter 8 mm; thickness 0.3 mm; and 6 mm diameter active spot. The source activities are 5 +/- 1 mCi and the alpha-line half-widths are equal to (1.7-2.5) and (2.9-4.5)% of full width at 10% of Maximum (Maximum is equal to 5.8 MeV). Thermovacuum (from 196 to 1000 degrees C), mechanical, and resource tests were performed and demonstrated that the sources maintained their characteristics. The applicability of the sources for the above-mentioned analytical purposes was confirmed during NASA Mars Pathfinder mission. PMID:11003526

  8. Effect of potassium sodium tartrate and sodium citrate on the preparation of {alpha}-calcium sulfate hemihydrate from flue gas desulfurization gypsum in a concentrated electrolyte solution

    SciTech Connect

    Shen, Z.X.; Guan, B.H.; Fu, H.L.; Yang, L.C.

    2009-12-15

    Flue gas desulfurization (FGD) gypsum mainly composed of calcium sulfate dihydrate (DH) was used as a raw material to obtain alpha-calcium sulfate hemihydrate ({alpha}-HH) through dehydration in a Ca-Mg-K-Cl-solution medium at 95{sup o}C under atmospheric pressure. The effects of potassium sodium tartrate and sodium citrate on the preparation of alpha-HH in the electrolyte solution were investigated. The results revealed that the addition of potassium sodium tartrate (1.0 x 10{sup -2} - 2.5 x 10{sup -2}M) decreased the dehydration rate of FGD gypsum and increased the length/width (l/w) ratio of {alpha}-HH crystals, which could yield unfavorable strength properties. Addition of sodium citrate (1.0 x 10{sup -5} - 2.0 x 10{sup -5}M) slightly increased the dehydration rate of FGD gypsum and decreased the l/w ratio of {alpha}-HH crystals, which could be beneficial to increase strength. However, it also led to a partial formation of anhydrite (AH) crystals. AH was also the only dehydration product when the concentration of sodium citrate increased to 1.0 x 10{sup -4}M. Therefore, sodium citrate rather than potassium sodium tartrate could be used as an additive in Ca-Mg-K-Cl electrolyte solutions if alpha-HH with a shorter l/w ratio is the desired product from FGD gypsum dehydration. The concentration of sodium citrate should be properly controlled to reduce the formation of AH.

  9. Tumour necrosis factor alpha antibody protects against lethal meningococcaemia.

    PubMed

    Nassif, X; Mathison, J C; Wolfson, E; Koziol, J A; Ulevitch, R J; So, M

    1992-03-01

    Tumour necrosis factor alpha (TNF-alpha) has been shown to be the principal mediator of Gram-negative bacterial endotoxin-induced shock. Nevertheless, evidence suggests that TNF-alpha plays a beneficial role in controlling bacterial infections when multiplication of the microorganism is required to kill the host. Using an infant rat model of Neisseria meningitidis infection, we found that blood TNF-alpha concentration reaches a peak three hours after intraperitoneal injection of 3 x 10(6) bacteria. Thereafter, the level of TNF-alpha decreased and was undetectable six to eight hours after infection. A correlation was observed between the magnitude of initial TNF-alpha response and a fatal outcome. Pretreatment of the animals with polyclonal anti-TNF antiserum significantly reduced mortality relative to animals pretreated with control serum. However, pretreatment of animals with anti-TNF antibody did not alter the bacterial invasion of the cerebrospinal fluid. Injection of heat-killed bacteria did not cause death and induced lower TNF-alpha levels than the same number of live bacteria. This excludes the possibility that the role of TNF-alpha is to mediate a shock induced by the endotoxin component of the bacterial inoculum. These results indicate that TNF-alpha has a deleterious effect in this model of bacteraemia. Identification of the critical factors that determine the action of TNF-alpha during lethal bacteraemia will lead to a better understanding of these diseases and the development of appropriate therapeutic intervention. PMID:1552859

  10. CHIP targets toxic alpha-Synuclein oligomers for degradation.

    PubMed

    Tetzlaff, Julie E; Putcha, Preeti; Outeiro, Tiago F; Ivanov, Alexander; Berezovska, Oksana; Hyman, Bradley T; McLean, Pamela J

    2008-06-27

    alpha-Synuclein (alphaSyn) can self-associate, forming oligomers, fibrils, and Lewy bodies, the pathological hallmark of Parkinson disease. Current dogma suggests that oligomeric alphaSyn intermediates may represent the most toxic alphaSyn species. Here, we studied the effect of a potent molecular chaperone, CHIP (carboxyl terminus of Hsp70-interacting protein), on alphaSyn oligomerization using a novel bimolecular fluorescence complementation assay. CHIP is a multidomain chaperone, utilizing both a tetratricopeptide/Hsp70 binding domain and a U-box/ubiquitin ligase domain to differentially impact the fate of misfolded proteins. In the current study, we found that co-expression of CHIP selectively reduced alphaSyn oligomerization and toxicity in a tetratricopeptide domain-dependent, U-box-independent manner by specifically degrading toxic alphaSyn oligomers. We conclude that CHIP preferentially recognizes and mediates degradation of toxic, oligomeric forms of alphaSyn. Further elucidation of the mechanisms of CHIP-induced degradation of oligomeric alphaSyn may contribute to the successful development of drug therapies that target oligomeric alphaSyn by mimicking or enhancing the powerful effects of CHIP. PMID:18436529

  11. Alpha Decay in the Complex-Energy Shell Model

    SciTech Connect

    Betan, R. Id

    2012-01-01

    Background: Alpha emission from a nucleus is a fundamental decay process in which the alpha particle formed inside the nucleus tunnels out through the potential barrier. Purpose: We describe alpha decay of 212Po and 104Te by means of the configuration interaction approach. Method: To compute the preformation factor and penetrability, we use the complex-energy shell model with a separable T = 1 interaction. The single-particle space is expanded in a Woods-Saxon basis that consists of bound and unbound resonant states. Special attention is paid to the treatment of the norm kernel appearing in the definition of the formation amplitude that guarantees the normalization of the channel function. Results: Without explicitly considering the alpha-cluster component in the wave function of the parent nucleus, we reproduce the experimental alpha-decay width of 212Po and predict an upper limit of T1/2 = 5.5 10 7 sec for the half-life of 104Te. Conclusions: The complex-energy shell model in a large valence configuration space is capable of providing a microscopic description of the alpha decay of heavy nuclei having two valence protons and two valence neutrons outside the doubly magic core. The inclusion of proton-neutron interaction between the valence nucleons is likely to shorten the predicted half-live of 104Te.

  12. Effects of Riparian Buffer Vegetation and Width: A 12-Year Longitudinal Study.

    PubMed

    King, S E; Osmond, D L; Smith, J; Burchell, M R; Dukes, M; Evans, R O; Knies, S; Kunickis, S

    2016-07-01

    Agricultural contributions of nitrogen are a serious concern for many water resources and have spurred the implementation of riparian buffer zones to reduce groundwater nitrate (NO). The optimum design for buffers is subject to debate, and there are few long-term studies. The objective of this project was to determine the effectiveness over time (12 yr) of buffer types (trees, switchgrass, fescue, native, and a control) and buffer widths (8 and 15 m) by measuring groundwater NO-N and dissolved organic carbon (DOC) trends. At the intermediate groundwater depth (1.5-2.1 m), NO-N reduction effectiveness was 2.5 times greater (46 vs. 16%) for the wider buffer, and, regardless of width, buffer effectiveness increased 0.62% yr. Buffer vegetative type was never statistically significant. In the deep-groundwater depth (2.1-3.5 m), there was no change in NO-N removal over time, although the statistical interaction of width and vegetative type indicated a wide range of removal rates (19-82%). The DOC concentrations were analyzed at the field/buffer and buffer/stream sampling locations. Depending on location position and groundwater sampling depth, DOC concentrations ranged from 1.6 to 2.8 mg L at Year 0 and increased at a rate of 0.13 to 0.18 mg L yr but always remained low (≤5.0 mg L). Greater DOC concentrations in the intermediate-depth groundwater did not increase NO-N removal; redox measurements indicated intermittent reduced soil conditions may have been limiting. This study suggests that riparian buffer width, not vegetation, is more important for NO-N removal in the middle coastal plain of North Carolina for a newly established buffer. PMID:27380072

  13. Astaxanthin reduces hepatic lipid accumulations in high-fat-fed C57BL/6J mice via activation of peroxisome proliferator-activated receptor (PPAR) alpha and inhibition of PPAR gamma and Akt.

    PubMed

    Jia, Yaoyao; Wu, Chunyan; Kim, Jiyoung; Kim, Bobae; Lee, Sung-Joon

    2016-02-01

    We have previously reported that astaxanthin (AX), a dietary carotenoid, directly interacts with peroxisome proliferator-activated receptors PPARα and PPARγ, activating PPARα while inhibiting PPARγ, and thus reduces lipid accumulation in hepatocytes in vitro. To investigate the effects of AX in vivo, high-fat diet (HFD)-fed C57BL/6J mice were orally administered AX (6 or 30mg/kg body weight) or vehicle for 8weeks. AX significantly reduced the levels of triglyceride both in plasma and in liver compared with the control HFD mice. AX significantly improved liver histology and thus reduced both steatosis and inflammation scores of livers with hematoxylin and eosin staining. The number of inflammatory macrophages and Kupffer cells were reduced in livers by AX administration assessed with F4/80 staining. Hepatic PPARα-responsive genes involved in fatty acid uptake and β-oxidation were upregulated, whereas inflammatory genes were downregulated by AX administration. In vitro radiolabeled assays revealed that hepatic fatty acid oxidation was induced by AX administration, whereas fatty acid synthesis was not changed in hepatocytes. In mechanism studies, AX inhibited Akt activity and thus decreased SREBP1 phosphorylation and induced Insig-2a expression, both of which delayed nuclear translocation of SREBP1 and subsequent hepatic lipogenesis. Additionally, inhibition of the Akt-mTORC1 signaling axis by AX stimulated hepatic autophagy that could promote degradation of lipid droplets. These suggest that AX lowers hepatic lipid accumulation in HFD-fed mice via multiple mechanisms. In addition to the previously reported differential regulation of PPARα and PPARγ, inhibition of Akt activity and activation of hepatic autophagy reduced hepatic steatosis in mouse livers. PMID:26878778

  14. Fan-less long range alpha detector

    DOEpatents

    MacArthur, Duncan W.; Bounds, John A.

    1994-01-01

    A fan-less long range alpha detector which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces.

  15. Fan-less long range alpha detector

    DOEpatents

    MacArthur, D.W.; Bounds, J.A.

    1994-05-10

    A fan-less long range alpha detector is disclosed which operates by using an electrical field between a signal plane and the surface or substance to be monitored for air ions created by collisions with alpha radiation. Without a fan, the detector can operate without the possibility of spreading dust and potential contamination into the atmosphere. A guard plane between the signal plane and the electrically conductive enclosure and maintained at the same voltage as the signal plane, reduces leakage currents. The detector can easily monitor soil, or other solid or liquid surfaces. 2 figures.

  16. Detonation cell widths in hydrogen-air-diluent mixtures

    SciTech Connect

    Stamps, D.W.

    1990-01-01

    In this paper I report on the influence of steam and carbon dioxide on the detonability of hydrogen-air mixtures. Data were obtained on the detonation cell width in a heated detonation tube that is 0.43 m in diameter and 13.1 m long. The detonation cell widths were correlated using a characteristic length calculated from a chemical kinetic model. The addition of either diluent to a hydrogen-air mixture increased the cell width for all equivalence ratios. For equal diluent concentrations, however, carbon dioxide not only yielded larger increases in the cell width than steam, but its efficacy relative to steam was predicted to increase with increasing concentration. The range of detonable hydrogen concentrations in a hydrogen-air mixture initially at 1 atm pressure was found to be between 11.6 percent and 74.9 percent for mixtures at 20{degree}C and 9.4 percent and 76.9 percent for mixtures at 100{degree}C. The detonation limit was between 38.8 percent and 40.5 percent steam for a stoichiometric hydrogen-air-steam mixture initially at 100{degree}C and 1 atm. 10 refs., 4 figs., 1 tab.

  17. An Empirical Expression for the Line Widths of Ammonia

    NASA Technical Reports Server (NTRS)

    Brown, Linda R.; Peterson, Dean B.

    1994-01-01

    The hydrogen-broadened line widths of 116 (sup 14)NH(sub 3) ground state transitions have been measured at 0.006 cm(sup -1) resolution using a Bruker spectrometer in the 24 to 210 cm(sup -1) region. The rotational variation of the experimental widths with J(sup '),K(sup ') = 1,0 to 10,10 has been reproduced to 2.4 % using an heuristically derived expression of the form

    gamma = a(sub 0) + a(sub 1) J(sup ') + a (sub 2) K(sup ') + a(sub 3) J(sup ')(sup 2) + a(sub 4) J(sup ') K(sup ')

    where J(sup ') and K(sup ') are the lower state symmetric top quantum numbers. This function has also been applied to the measured widths of the 58 transitions of nu(sub 1) at 3 (micro)m, each broadened by N(sub 2), O(sub 2), Ar, H(sub 2), and He. The rms of the observed minus calculated widths are 5% or better for the five foreign broadeners. The values of the fitted constants suggest that for some broadeners the expression might also be written as

    gamma = a(sub 0) + b(sub 1) J(sup ') + b(sub 2)(J(sup ' )- K(sup ')) + b(sub 3) J(sup ')(J(sup ') - K(sup '))

    .

  18. 13. DETAIL: A CLOSEUP VIEW OF TWO UNEQUAL WIDTH CONCRETE ...

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

    13. DETAIL: A CLOSE-UP VIEW OF TWO UNEQUAL WIDTH CONCRETE BRACKETS AND THE LARGE CAST ANCONE WHICH SUPPORTS A QUIRK IN THE CONCRETE BALUSTRADE. - Delphi Bridge on U.S. Route 421, Spanning Deer Creek at U.S. Route 421, Delphi, Carroll County, IN

  19. Supercycles at subduction thrusts controlled by seismogenic zone downdip width

    NASA Astrophysics Data System (ADS)

    van Dinther, Y.; Herrendoerfer, R.; Gerya, T.; Dalguer, L. A.

    2014-12-01

    Supercycles in subduction zones describe a long-term cluster of megathrust earthquakes, which recur in a similar way (Sieh et al. 2008,Goldfinger et al. 2013). It consists of two complete failures of a given subduction segment in between which, after a long period of relative quiescence, partial ruptures occur. We recognize that supercycles were proposed in those subduction zones (Sieh et al. 2008,Goldfinger et al. 2013, Metois et al. 2014, Chlieh et al. 2014) for which the seismogenic zone downdip width is estimated to be larger than average (Heuret et al. 2011, Hayes et al. 2012). We show with a two-dimensional numerical model of a subduction zone that the seismogenic zone downdip width indeed has a strong influence on the long-term seismicity pattern and rupture styles. Increasing the downdip width of the seismogenic zone leads to a transition from ordinary cycles of similar sized crack-like ruptures to supercycles consisting of a range of rupture sizes and styles. Our model demonstrates how interseismic deformation accompanied by subcritical and pulse-like ruptures effectively increases the stress throughout the seismogenic zone towards a critical state at which a crack-like superevent releases most of the accumulated stresses. We propose such stress evolution along the dip of the megathrust as the simplest explanation for supercycles. This conceptual model suggests that larger than thus far observed earthquakes could occur as part of a supercycle in subduction zones with a larger than average seismogenic zone downdip width (>120-150 km).

  20. Improved determination of the width of the top quark

    SciTech Connect

    Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M. -C.; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goussiou A.; Graf C. P.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph.; Grivaz J. -F.; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; La Cruz I. Heredia-De; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jamin D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; de Sa R. Lopes; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; et al.

    2012-05-04

    We present an improved determination of the total width of the top quark, {Gamma}{sub t}, using 5.4 fb{sup -1} of integrated luminosity collected by the D0 Collaboration at the Tevatron p{bar p} Collider. The total width {Gamma}{sub t} is extracted from the partial decay width {Gamma}(t {yields} Wb) and the branching fraction {Beta}(t {yields} Wb). {Gamma}(t {yields} Wb) is obtained from the t-channel single top-quark production cross section and {Beta}(t {yields} Wb) is measured in t{bar t} events. For a top mass of 172.5 GeV, the resulting width is {Gamma}{sub t} = 2.00{sub -0.43}{sup +0.47} GeV. This translates to a top-quark lifetime of {tau}{sub t} = (3.29{sub -0.63}{sup +0.90}) x 10{sup -25} s. We also extract an improved direct limit on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix element 0.81 < |V{sub tb}| {le} 1 at 95% C.L. and a limit of |V{sub tb}| < 0.59 for a high-mass fourth-generation bottom quark assuming unitarity of the fourth-generation quark-mixing matrix.

  1. The complete cDNA sequence of laminin alpha 4 and its relationship to the other human laminin alpha chains.

    PubMed

    Richards, A; Al-Imara, L; Pope, F M

    1996-06-15

    We previously localised the gene (LAMA4) encoding a novel laminin alpha 4 chain to chromosome 6q21. In this study, we describe the complete coding sequence and compare the protein with the other three known human laminin alpha chains. Although closely linked to LAMA2, the LAMA4 product most closely resembles laminin alpha 3, a constituent of laminin 5. Like laminin alpha 3A, the alpha 4 chain is a truncated version of the alpha 1 and alpha 2 chains, with a much reduced short arm. While the alpha 4 molecule is most similar to alpha 3, it shares some features of the C-terminal domains G4 and G5 in common with alpha 2. Unlike the LAMA3 gene, LAMA4 appears to encode only a single transcript, as determined by 5' rapid amplification of cDNA ends. The cDNA sequence encodes 1816 amino acids, which include a 24-residue signal peptide. The gene is expressed in skin, placenta, heart, lung, skeletal muscle, and pancreas. We have also shown that the mRNA can be readily reverse transcribed and amplified from cultured dermal fibroblasts. PMID:8706685

  2. ALPHA MIS: Reference manual

    SciTech Connect

    Lovin, J.K.; Haese, R.L.; Heatherly, R.D.; Hughes, S.E.; Ishee, J.S.; Pratt, S.M.; Smith, D.W.

    1992-02-01

    ALPHA is a powerful and versatile management information system (MIS) initiated and sponsored and by the Finance and Business Management Division of Oak Ridge National Laboratory, who maintain and develop it in concert with the Business Systems Division for its Information Center. A general-purpose MIS, ALPHA allows users to access System 1022 and System 1032 databases to obtain and manage information. From a personal computer or a data terminal, Energy Systems employees can use ALPHA to control their own report reprocessing. Using four general commands (Database, Select, Sort, and Report) they can (1) choose a mainframe database, (2) define subsets within it, (3) sequentially order a subset by one or more variables, and (4) generate a report with their own or a canned format.

  3. Design of multiplier-less sharp transition width non-uniform filter banks using gravitational search algorithm

    NASA Astrophysics Data System (ADS)

    Bindiya T., S.; Elias, Elizabeth

    2015-01-01

    In this paper, multiplier-less near-perfect reconstruction tree-structured filter banks are proposed. Filters with sharp transition width are preferred in filter banks in order to reduce the aliasing between adjacent channels. When sharp transition width filters are designed as conventional finite impulse response filters, the order of the filters will become very high leading to increased complexity. The frequency response masking (FRM) method is known to result in linear-phase sharp transition width filters with low complexity. It is found that the proposed design method, which is based on FRM, gives better results compared to the earlier reported results, in terms of the number of multipliers when sharp transition width filter banks are needed. To further reduce the complexity and power consumption, the tree-structured filter bank is made totally multiplier-less by converting the continuous filter bank coefficients to finite precision coefficients in the signed power of two space. This may lead to performance degradation and calls for the use of a suitable optimisation technique. In this paper, gravitational search algorithm is proposed to be used in the design of the multiplier-less tree-structured uniform as well as non-uniform filter banks. This design method results in uniform and non-uniform filter banks which are simple, alias-free, linear phase and multiplier-less and have sharp transition width.

  4. Lithologic controls on valley width and strath terrace formation

    NASA Astrophysics Data System (ADS)

    Schanz, Sarah A.; Montgomery, David R.

    2016-04-01

    Valley width and the degree of bedrock river terrace development vary with lithology in the Willapa and Nehalem river basins, Pacific Northwest, USA. Here, we present field-based evidence for the mechanisms by which lithology controls floodplain width and bedrock terrace formation in erosion-resistant and easily friable lithologies. We mapped valley surfaces in both basins, dated straths using radiocarbon, compared valley width versus drainage area for basalt and sedimentary bedrock valleys, and constructed slope-area plots. In the friable sedimentary bedrock, valleys are 2 to 3 times wider, host flights of strath terraces, and have concavity values near 1; whereas the erosion-resistant basalt bedrock forms narrow valleys with poorly developed, localized, or no bedrock terraces and a channel steepness index half that of the friable bedrock and an average channel concavity of about 0.5. The oldest dated strath terrace on the Willapa River, T2, was active for nearly 10,000 years, from 11,265 to 2862 calibrated years before present (cal YBP), whereas the youngest terrace, T1, is Anthropocene in age and recently abandoned. Incision rates derived from terrace ages average 0.32 mm y- 1 for T2 and 11.47 mm y- 1 for T1. Our results indicate bedrock weathering properties influence valley width through the creation of a dense fracture network in the friable bedrock that results in high rates of lateral erosion of exposed bedrock banks. Conversely, the erosion-resistant bedrock has concavity values more typical of detachment-limited streams, exhibits a sparse fracture network, and displays evidence for infrequent episodic block erosion and plucking. Lithology thereby plays a direct role on the rates of lateral erosion, influencing valley width and the potential for strath terrace planation and preservation.

  5. A reconsideration of spectral width measurements in PMSE with EISCAT

    NASA Astrophysics Data System (ADS)

    Rapp, Markus; Hoppe, Ulf-Peter

    2006-01-01

    Motivated by recent progress in the understanding of PMSE we have reconsidered the relation between observed echo power and spectral widths. We have analyzed data obtained with the EISCAT VHF radar operating at a vertical resolution of 300 m and a time resolution of 2 s. Considering the spatial and temporal morphology of echo power, spectral width, and vertical velocity, we have identified a dominant anti-correlation between power and spectral width. This anti-correlation has formerly been interpreted as evidence against a turbulent creation mechanism for PMSE. Taking into account state of the art direct numerical simulations and their application to the interpretation of radar backscatter from the mesopause region, we find, however, that from theory we indeed expect to find the observed anti-correlation. The main reason for this is a clear spatial separation between the maxima of turbulent kinetic energy dissipation (i.e., velocity fluctuations determining the spectral width) and the thermal dissipation (i.e., the production of fluctuations in a tracer like the electron number density) associated with turbulence being due to both Kelvin-Helmholtz instabilities and gravity wave breakdown (Fritts, D.C., Bizon, C., Werne, J., Meyer, C. Layering accompanying turbulence generation due to shear instability and gravity-wave breaking. J. Geophys. Res. 108(D8), 8452, doi:10.1029/2001JD002406, 2003). This means that the observed anti-correlation between radar echo power and spectral width does not rule out a turbulence-related creation mechanisms for PMSE. In fact, the observations are in full agreement with the best available direct numerical calculations of the related physical processes.

  6. FREQUENCY DEPENDENCE OF PULSE WIDTH FOR 150 RADIO NORMAL PULSARS

    SciTech Connect

    Chen, J. L.; Wang, H. G.

    2014-11-01

    The frequency dependence of the pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, for which the 10% multifrequency pulse widths can be well fit with the Thorsett relationship W {sub 10} = Aν{sup μ} + W {sub 10,} {sub min}. The relative fraction of pulse width change between 0.4 GHz and 4.85 GHz, η = (W {sub 4.85} – W {sub 0.4})/W {sub 0.4}, is calculated in terms of the best-fit relationship for each pulsar. It is found that 81 pulsars (54%) have η < –10% (group A), showing considerable profile narrowing at high frequencies, 40 pulsars (27%) have –10% ≤η ≤ 10% (group B), meaning a marginal change in pulse width, and 29 pulsars (19%) have η > 10% (group C), showing a remarkable profile broadening at high frequencies. The fractions of the group-A and group-C pulsars suggest that the profile narrowing phenomenon at high frequencies is more common than the profile broadening phenomenon, but a large fraction of the group-B and group-C pulsars (a total of 46%) is also revealed. The group-C pulsars, together with a portion of group-B pulsars with slight pulse broadening, can hardly be explained using the conventional radius-to-frequency mapping, which only applies to the profile narrowing phenomenon. Based on a recent version of the fan beam model, a type of broadband emission model, we propose that the diverse frequency dependence of pulse width is a consequence of different types of distribution of emission spectra across the emission region. The geometrical effect predicting a link between the emission beam shrinkage and spectrum steepening is tested but disfavored.

  7. Microdosimetry for Targeted Alpha Therapy of Cancer

    PubMed Central

    Huang, Chen-Yu; Guatelli, Susanna; Oborn, Bradley M.; Allen, Barry J.

    2012-01-01

    Targeted alpha therapy (TAT) has the advantage of delivering therapeutic doses to individual cancer cells while reducing the dose to normal tissues. TAT applications relate to hematologic malignancies and now extend to solid tumors. Results from several clinical trials have shown efficacy with limited toxicity. However, the dosimetry for the labeled alpha particle is challenging because of the heterogeneous antigen expression among cancer cells and the nature of short-range, high-LET alpha radiation. This paper demonstrates that it is inappropriate to investigate the therapeutic efficacy of TAT by macrodosimetry. The objective of this work is to review the microdosimetry of TAT as a function of the cell geometry, source-target configuration, cell sensitivity, and biological factors. A detailed knowledge of each of these parameters is required for accurate microdosimetric calculations. PMID:22988479

  8. [Voluntary alpha-power increasing training impact on the heart rate variability].

    PubMed

    Bazanova, O M; Balioz, N V; Muravleva, K B; Skoraia, M V

    2013-01-01

    In order to study the effect of the alpha EEG power increasing training at heart rate variability (HRV) as the index of the autonomic regulation of cognitive functions there were follow tasks: (1) to figure out the impact of biofeedback in the voluntary increasing the power in the individual high-frequency alpha-band effect on heart rate variability and related characteristics of cognitive and emotional spheres, (2) to determine the nature of the relationship between alpha activity indices and heart rate variability, depending on the alpha-frequency EEG pattern at rest (3) to examine how the individual alpha frequency EEG pattern is reflected in changes HRV as a result of biofeedback training. Psychometric indicators of cognitive performance, the characteristics of the alpha-EEG activity and heart rate variability (HRV) as LF/HF and pNN50 were recorded in 27 healthy men aged 18-34 years, before, during, and after 10 sessions of training of voluntary increase in alpha power in the individual high-frequency alpha band with eyes closed. To determine the biofeedback effect on the alpha power increasing training, data subjects are compared in 2 groups: experimental (14) with the real and the control group (13 people)--with mock biofeedback. The follow up effect of trainings was studied through month over the 10 training sessions. Results showed that alpha biofeedback training enhanced the fluency and accuracy in cognitive performance, decreased anxiety and frontal EMG, increased resting frequency, width and power in individual upper alpha range only in participants with low baseline alpha frequency. While mock biofeedback increased resting alpha power only in participants with high baseline resting alpha frequency and did change neither cognitive performance, nor HRV indices. Biofeedback training eliminated the alpha power decrease in response to arithmetic task in both with high and low alpha frequency participants and this effect was followed up over the month. Mock

  9. a Linear Model for Meandering Rivers with Arbitrarily Varying Width

    NASA Astrophysics Data System (ADS)

    Frascati, A.; Lanzoni, S.

    2011-12-01

    Alluvial rivers usually exhibit quite complex planforms, characterized by a wide variety of alternating bends, that have attracted the interest of a large number of researchers. Much less attention has been paid to another striking feature observed in alluvial rivers, namely the relatively regular spatial variations attained by the channel width. Actively meandering channels, in fact, generally undergo spatial oscillations systematically correlated with channel curvature, with cross sections wider at bends than at crossings. Some other streams have been observed to exhibit irregular width variations. Conversely, rivers flowing in highly vegetated flood plains, i.e. canaliform rivers, may exhibit an opposite behavior, owing to the combined effects of bank erodibility and floodplain depositional processes which, in turn, are strictly linked to vegetation cover. Similarly to streamline curvatures induced by bends, the presence of along channel width variations may have remarkable effects on the flow field and sediment dynamics and, thereby, on the equilibrium river bed configuration. In particular, spatial distribution of channel curvature typically determines the formation of a rhythmic bar-pool pattern in the channel bed strictly associated with the development of river meanders. Channel width variations are on the contrary characterized by a sequence of narrowing, yielding a central scour, alternated to the downstream development of a widening associated with the formation of a central bar. Here we present a morphodynamic model that predict at a linear level the spatial distribution of the flow field and the equilibrium bed configuration of an alluvial river characterized by arbitrary along channel distributions of both the channel axis curvature and the channel width. The mathematical model is averaged over the depth and describes the steady, non-uniform flow and sediment transport in sinuous channels with a noncohesive bed. The governing two-dimensional equations

  10. [alpha]-Oxocarboxylic Acids

    ERIC Educational Resources Information Center

    Kerber, Robert C.; Fernando, Marian S.

    2010-01-01

    Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

  11. From Alpha to Omega

    ERIC Educational Resources Information Center

    Czaja, Paul Clement

    2006-01-01

    The Alpha point of the authors' life as a Montessori educator began in 1959, when he was a graduate student studying philosophy at Fordham University in the Bronx, New York. While studying the works of the great American philosopher William James, the author came across the writings of Maria Montessori and immediately became captivated by her…

  12. Flow measurements in two cambered vane diffusers with different passage widths

    NASA Astrophysics Data System (ADS)

    Stein, W.; Rautenberg, M.

    1985-03-01

    To investigate the influence of the vaneless space between impeller exit and the diffuser vanes, detailed flow measurements in two diffusers with the same vane geometry but different passage width are compared. The three-dimensional character of the flow changes between impeller exit and the entry to the two dimensional vanes depending on the shape of the shroud. After initial measurements with a constant area vaneless space, the width of the vaned diffuser was later on reduced by 10 percent. The compressor maps show increases in overall pressure rise and efficiency with the width reduction. To get further details of the flow field, measurements of the static pressure distribution at hub and shroud have been performed at several operation points for both diffusers. At the same points, the flow angle and total pressure distribution between hub and shroud upstream and downstream of the vanes have been measured with probes. The maximum efficiency of the narrow diffuser is nearly 2 percent higher than for the wide diffuser. The measurements give further details to explain this improvement.

  13. Stark width measurements of Fe II lines with wavelengths in the range 260-300 nm

    NASA Astrophysics Data System (ADS)

    Aragón, C.; Vega, P.; Aguilera, J. A.

    2011-03-01

    The Stark widths of 21 Fe II lines with wavelengths in the range 260-300 nm have been measured using laser-induced plasmas as spectroscopic sources. A set of Fe-Cu samples has been employed to generate the plasmas. To reduce self-absorption, each line has been measured using a different sample, with an iron concentration determined by means of the curve-of-growth methodology. The remaining error due to self-absorption has been estimated to be lower than 10%. Different instants of the plasma evolution, from 0.84 to 2.5 µs, are included in the measurements. The electron density, in the range (1.6-7.3) × 1017 cm-3, is determined by the Stark broadening of the Hα line. Within this range, the Stark widths are found to be proportional to the electron density. The Boltzmann plot method is used to obtain the plasma temperature, which is in the range 12 900-15 200 K. The Stark widths obtained have been compared with available experimental and theoretical data.

  14. Vespertilionid bats control the width of their biosonar sound beam dynamically during prey pursuit

    PubMed Central

    Jakobsen, Lasse; Surlykke, Annemarie

    2010-01-01

    Animals using sound for communication emit directional signals, focusing most acoustic energy in one direction. Echolocating bats are listening for soft echoes from insects. Therefore, a directional biosonar sound beam greatly increases detection probability in the forward direction and decreases off-axis echoes. However, high directionality has context-specific disadvantages: at close range the detection space will be vastly reduced, making a broad beam favorable. Hence, a flexible system would be very advantageous. We investigated whether bats can dynamically change directionality of their biosonar during aerial pursuit of insects. We trained five Myotis daubentonii and one Eptesicus serotinus to capture tethered mealworms and recorded their echolocation signals with a multimicrophone array. The results show that the bats broaden the echolocation beam drastically in the terminal phase of prey pursuit. M. daubentonii increased the half-amplitude angle from approximately 40° to approximately 90° horizontally and from approximately 45° to more than 90° vertically. The increase in beam width is achieved by lowering the frequency by roughly one octave from approximately 55 kHz to approximately 27.5 kHz. The E. serotinus showed beam broadening remarkably similar to that of M. daubentonii. Our results demonstrate dynamic control of beam width in both species. Hence, we propose directionality as an explanation for the frequency decrease observed in the buzz of aerial hawking vespertilionid bats. We predict that future studies will reveal dynamic control of beam width in a broad range of acoustically communicating animals. PMID:20643943

  15. Stark broadening for diagnostics of the electron density in non-equilibrium plasma utilizing isotope hydrogen alpha lines

    SciTech Connect

    Yang, Lin; Tan, Xiaohua; Wan, Xiang; Chen, Lei; Jin, Dazhi; Qian, Muyang; Li, Gongping

    2014-04-28

    Two Stark broadening parameters including FWHM (full width at half maximum) and FWHA (full width at half area) of isotope hydrogen alpha lines are simultaneously introduced to determine the electron density of a pulsed vacuum arc jet. To estimate the gas temperature, the rotational temperature of the C{sub 2} Swan system is fit to 2500 ± 100 K. A modified Boltzmann-plot method with b{sub i}-factor is introduced to determine the modified electron temperature. The comparison between results of atomic and ionic lines indicates the jet is in partial local thermodynamic equilibrium and the electron temperature is close to 13 000 ± 400 K. Based on the computational results of Gig-Card calculation, a simple and precise interpolation algorithm for the discrete-points tables can be constructed to obtain the traditional n{sub e}-T{sub e} diagnostic maps of two Stark broadening parameters. The results from FWHA formula by the direct use of FWHM = FWHA and these from the diagnostic map are different. It can be attributed to the imprecise FWHA formula form and the deviation between FWHM and FWHA. The variation of the reduced mass pair due to the non-equilibrium effect contributes to the difference of the results derived from two hydrogen isotope alpha lines. Based on the Stark broadening analysis in this work, a corrected method is set up to determine n{sub e} of (1.10 ± 0.08) × 10{sup 21} m{sup −3}, the reference reduced mass μ{sub 0} pair of (3.30 ± 0.82 and 1.65 ± 0.41), and the ion kinetic temperature of 7900 ± 1800 K.

  16. Effects of specimen width and rolling direction on the mechanical properties of beryllium copper alloy C17200

    NASA Astrophysics Data System (ADS)

    Lee, W. C.; Liu, Z. R.

    2015-12-01

    The objective of the research was to study the effects of specimen width and rolling direction of beryllium copper alloy, C17200, on the mechanical properties of yield strength and Young's modulus. The experimental results showed that the reduction of the specimen width from 12.5 mm to 2.5 mm did not affect the yield strength but reduced the Young's modulus by 4%. Also, the change of rolling direction affected both the yield strength and the Young's modulus. When the tension direction is parallel to the rolling direction, the maximum yield strength was obtained. The results can help predict the behavior of small-scale beryllium copper products more accurately.

  17. Comparator threshold settings and the effective pixel width of the PICASSO detector

    NASA Astrophysics Data System (ADS)

    Lopez, F. C. M.; Rigon, L.; Fardin, L.; Arfelli, F.; Bergamaschi, A.; Dreossi, D.; Longo, M.; Schmitt, B.; Vallazza, E.; Longo, R.

    2014-05-01

    Charge sharing plays an important role in the performance of single-photon counting microstrip detectors, since the comparator threshold defines the effective pixel width. In this contribution, the PICASSO (Phase Imaging for Clinical Application with Silicon detector and Synchrotron radiatiOn) single-photon counting microstrip detector oriented in edge-on configuration has been used to study its spatial resolution as a function of the comparator threshold. The experiment was carried out with monochromatic x-rays at the SYRMEP beamline of the Elettra synchrotron radiation facility in Trieste (Italy). The Edge Spread Function (i.e. the integral of the Line spread Function, LSF) was measured by horizontally translating vertical slits from a bar-pattern test-object in front of the detector, at four different photon energies (19, 20, 22, and 25 keV) and for several different values of the comparator threshold. The effect of charge sharing between strips on the spatial resolution has been quantified by calculating the horizontal Modulation Transfer Function (MTF). Moreover, the composite LSF from neighboring pixels was obtained: this allowed estimating the optimal threshold for each photon energy by selecting the threshold at which the composite LSF would approach unity along the entire width of the pixel. The results show that at thresholds lower than half of the photon energy, charge sharing increases the effective pixel width, causing a drop of the MTF, and it is responsible for the appearance of peaks in the composite LSF. Conversely, at thresholds higher than half of the photon energy, the effective pixel width is reduced and the spatial resolution is increased, but the collection efficiency is compromised, as demonstrated by the presence of valleys in the composite LSF.

  18. Determination of the width of the top quark.

    PubMed

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Aoki, M; Arnoud, Y; Arov, M; Askew, A; Åsman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bazterra, V; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brandt, O; Brock, R; Brooijmans, G; Bross, A; Brown, D; Brown, J; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calpas, B; Camacho-Pérez, E; Carrasco-Lizarraga, M A; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Chen, G; Chevalier-Théry, S; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Croc, A; Cutts, D; Ćwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De la Cruz-Burelo, E; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; DeVaughan, K; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerbaudo, D; Gerber, C E; Gershtein, Y; Ginther, G; Golovanov, G; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Hagopian, S; Haley, J; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Head, T; Hebbeker, T; Hedin, D; Hegab, H; Heinson, A P; Heintz, U; Hensel, C; Heredia-De la Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jamin, D; Jesik, R; Johns, K; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Joshi, J; Juste, A; Kaadze, K; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kohli, J M; Kozelov, A V; Kraus, J; Kumar, A; Kupco, A; Kurča, T; Kuzmin, V A; Kvita, J; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, S W; Lee, W M; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Madar, R; Magaña-Villalba, R; Malik, S; Malyshev, V L; Maravin, Y; Martínez-Ortega, J; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Muanza, G S; Mulhearn, M; Nagy, E; Naimuddin, M; Narain, M; Nayyar, R; Neal, H A; Negret, J P; Neustroev, P; Novaes, S F; Nunnemann, T; Obrant, G; Orduna, J; Osman, N; Osta, J; Otero y Garzón, G J; Owen, M; Padilla, M; Pangilinan, M; Parashar, N; Parihar, V; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Petrillo, G; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Price, D; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rangel, M S; Ranjan, K; Ratoff, P N; Razumov, I; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Santos, A S; Savage, G; Sawyer, L; Scanlon, T; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shary, V; Shchukin, A A; Shivpuri, R K; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Smith, K J; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S; Sonnenschein, L; Sopczak, A; Sosebee, M; Soustruznik, K; Spurlock, B; Stark, J; Stolin, V; Stoyanova, D A; Strauss, E; Strauss, M; Strom, D; Stutte, L; Svoisky, P; Takahashi, M; Tanasijczuk, A; Taylor, W; Titov, M; Tokmenin, V V; Tsybychev, D; Tuchming, B; Tully, C; Tuts, P M; Uvarov, L; Uvarov, S; Uzunyan, S; Van Kooten, R; van Leeuwen, W M; Varelas, N; Varnes, E W; Vasilyev, I A; Verdier, P; Vertogradov, L S; Verzocchi, M; Vesterinen, M; Vilanova, D; Vint, P; Vokac, P; Wahl, H D; Wang, M H L S; Warchol, J; Watts, G; Wayne, M; Weber, M; Welty-Rieger, L; Wetstein, M; White, A; Wicke, D; Williams, M R J; Wilson, G W; Wimpenny, S J; Wobisch, M; Wood, D R; Wyatt, T R; Xie, Y; Xu, C; Yacoob, S; Yamada, R; Yang, W-C; Yasuda, T; Yatsunenko, Y A; Ye, Z; Yin, H; Yip, K; Yoo, H D; Youn, S W; Yu, J; Zelitch, S; Zhao, T; Zhou, B; Zhu, J; Zielinski, M; Zieminska, D; Zivkovic, L

    2011-01-14

    We extract the total width of the top quark, Γ(t), from the partial decay width Γ(t → Wb) measured using the t-channel cross section for single top-quark production and from the branching fraction B(t → Wb) measured in tt events using up to 2.3  fb(-1) of integrated luminosity collected by the D0 Collaboration at the Tevatron pp Collider. The result is Γ(t) = 1.99(-0.55)(+0.69)  GeV, which translates to a top-quark lifetime of τ(t) = (3.3(-0.9)(+1.3)) × 10(-25)   s. Assuming a high mass fourth generation b' quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V(tb')| < 0.63 at 95% C.L. PMID:21405220

  19. Photospheric Line Equivalent Widths in Calcium K Faculae

    NASA Astrophysics Data System (ADS)

    Walton, S. R.; Preminger, D. G.; Chapman, G. A.; Cookson, A. M.

    2003-05-01

    We have recently shown (Preminger, Walton, and Chapman 2002) that the total solar irradiance S can be modeled by a linear combination of photometric quantities which measure the fractional brightness change in the continuum and in the Ca II K line. We concluded that the change in S on solar cycle time scales is caused by variations in spectral lines, not in the continuum. In order to further test this conclusion, we have begun comparing our photometric Ca II K images with line equivalent width maps made in Fe I 6302.5. Bright features in our K images are well correlated with areas of lower equivalent width. We are beginning to quantitatively measure this correlation and will present further results at the meeting. This research has been supported by NSF grant ATM-9912132.

  20. Direct measurement of W boson decay width at DO

    NASA Astrophysics Data System (ADS)

    Xu, Qichun

    This thesis presents the first direct measurement of the W boson decay width, ΓW, with the W decay into an electron and neutrino final state using data collected by the DØ detector at the Tevatran collider. This analysis has used the W event sample collected in the Run I physics program. Backgrounds that contaminate the W sample are estimated using additional DØ data samples. Detailed Monte Carlo samples are used to template the transverse mass spectrum of the W events to extract the W decay width. Various sources of the systematic uncertainties of this measurement are investigated. The direct measurement result obtained in this thesis work is ΓW = 2.231+0.145-0.138(stat) +/- 0.092(sys) GeV. This result is consistent with the prediction of the Standard Model and the result from the indirect measurement from the DØ experiment.

  1. A Direct Measurement of the $W$ Decay Width

    SciTech Connect

    Vine, Troy

    2008-08-01

    A direct measurement of the W boson total decay width is presented in proton-antiproton collisions at √s = 1.96 TeV using data collected by the CDF II detector. The measurement is made by fitting a simulated signal to the tail of the transverse mass distribution in the electron and muon decay channels. An integrated luminosity of 350 pb-1 is used, collected between February 2002 and August 2004. Combining the results from the separate decay channels gives the decay width as 2.038 ± 0.072 GeV in agreement with the theoretical prediction of 2.093 ± 0.002 GeV. A system is presented for the management of detector calibrations using a relational database schema. A description of the implementation and monitoring of a procedure to provide general users with a simple interface to the complete set of calibrations is also given.

  2. Tunable plasmonic Bragg reflector with different graphene nanoribbon widths

    NASA Astrophysics Data System (ADS)

    Zhuang, Huawei; Kong, Fanmin; Li, Kang; Sheng, Shiwei

    2015-09-01

    We propose and numerically analyze a Bragg reflector composed of periodically arranged graphene nanoribbon waveguides with different widths. Because of the unique property of the graphene edge mode, the effective index contrast used for the reflector can be obtained by designing graphene nanoribbons with different widths without changing the dielectric substrate structure. Good band stop filtering characteristics are shown at the band gap of the transmission spectrum by numerical simulation. The performance of the proposed Bragg reflector is analyzed in terms of different parameters, such as the chemical potential, the number of periods, and the size of the unit cell. The proposed Bragg reflector will be expected to have important potential applications in the highly integrated SPP-based photonic devices.

  3. Summary of Alpha Particle Transport

    SciTech Connect

    Medley, S.S.; White, R.B.; Zweben, S.J.

    1998-08-19

    This paper summarizes the talks on alpha particle transport which were presented at the 5th International Atomic Energy Agency's Technical Committee Meeting on "Alpha Particles in Fusion Research" held at the Joint European Torus, England in September 1997.

  4. Alpha Condensates in Atomic Nuclei

    SciTech Connect

    Suzuki, Y.; Matsumura, H.

    2005-11-21

    Recent issues on Bose-Einstein condensation (BEC) of {alpha}-particles in nuclei are reviewed. A candidate of condensates is discussed for some states in 12C and 16O by defining the amount of {alpha} condensation.

  5. Beam Width Robustness of a 670 GHz Imaging Radar

    NASA Technical Reports Server (NTRS)

    Cooper, K. B.; Llombart, N.; Dengler, R. J.; Siegel, P. H.

    2009-01-01

    Detection of a replica bomb belt concealed on a mannequin at 4 m standoff range is achieved using a 670 GHz imaging radar. At a somewhat larger standoff range of 4.6 m, the radar's beam width increases substantially, but the through-shirt image quality remains good. This suggests that a relatively modest increase in aperture size over the current design will be sufficient to detect person-borne concealed weapons at ranges exceeding 25 meters.

  6. Single event effects in pulse width modulation controllers

    SciTech Connect

    Penzin, S.H.; Crain, W.R.; Crawford, K.B.; Hansel, S.J.; Kirshman, J.F.; Koga, R.

    1996-12-01

    SEE testing was performed on pulse width modulation (PWM) controllers which are commonly used in switching mode power supply systems. The devices are designed using both Set-Reset (SR) flip-flops and Toggle (T) flip-flops which are vulnerable to single event upset (SEU) in a radiation environment. Depending on the implementation of the different devices the effect can be significant in spaceflight hardware.

  7. Do coralline red algal growth increment widths archive paleoenvironmental information?

    NASA Astrophysics Data System (ADS)

    Halfar, J.; Winsborough, C.; Omar, A.; Hetzinger, S.; Steneck, R. S.; Lebednik, P. A.

    2009-04-01

    Over the past decade coralline red algae have received increased attention as archives of paleoclimate information. Encrusting coralline red algae, which deposit annual growth increments in a High-Mg calcite skeleton, are amongst the longest-lived marine organisms. In fact, a live-collected plant has recently been shown to have lived for at least 850 years based on radiometric dating. While a number of investigations have successfully utilized geochemical information obtained from coralline red algal skeletons to reconstruct climate, no study has yet examined the potential of using growth increment widths as a proxy for past water temperatures. Here we explore the relationship between growth and environmental parameters in Clathromorphum nereostratum from the Bering Sea. A 120-year long annual growth record shows a significant but weak correlation to regional sea surface temperature data (r=0.24), which requires much of the observed annual growth increment width variability to be explained by other factors. We therefore examined coralline red algal growth for a 20-year period in multiple specimens collected along a depth transect from 10 to 35 m water depth. Results demonstrate a significant decrease in average annual growth increment widths with increasing water depth. Due to intense wind-induced mixing in the region the upper water column exhibits near uniform temperatures and salinities, leaving the decreasing amount of light with depth as the dominant variable influencing vertical extension. This was further tested by examining specimens collected at 10 m water depth at different locations receiving distinct amounts of shading provided by 100%, 50%, and 0% kelp canopy coverage. Results indicate a negative relationship between percent kelp canopy coverage and annual growth increment width. It can therefore be concluded that the dominant factor controlling vertical growth in C. nereostratum is light, with temperature only accounting for a small portion of growth

  8. Characterizing the width of amphibian movements during postbreeding migration.

    PubMed

    Coster, Stephanie S; Veysey Powell, Jessica S; Babbitt, Kimberly J

    2014-06-01

    Habitat linkages can help maintain connectivity of animal populations in developed landscapes. However, the lack of empirical data on the width of lateral movements (i.e., the zigzagging of individuals as they move from one point to point another) makes determining the width of such linkages challenging. We used radiotracking data from wood frogs (Lithobates sylvaticus) and spotted salamanders (Ambystoma maculatum) in a managed forest in Maine (U.S.A.) to characterize movement patterns of populations and thus inform planning for the width of wildlife corridors. For each individual, we calculated the polar coordinates of all locations, estimated the vector sum of the polar coordinates, and measured the distance from each location to the vector sum. By fitting a Gaussian distribution over a histogram of these distances, we created a population-level probability density function and estimated the 50th and 95th percentiles to determine the width of lateral movement as individuals progressed from the pond to upland habitat. For spotted salamanders 50% of lateral movements were ≤13 m wide and 95% of movements were ≤39 m wide. For wood frogs, 50% of lateral movements were ≤17 m wide and 95% of movements were ≤ 51 m wide. For both species, those individuals that traveled the farthest from the pond also displayed the greatest lateral movement. Our results serve as a foundation for spatially explicit conservation planning for pond-breeding amphibians in areas undergoing development. Our technique can also be applied to movement data from other taxa to aid in designing habitat linkages. PMID:24423254

  9. Pulse-Width-Modulating Driver for Brushless dc Motor

    NASA Technical Reports Server (NTRS)

    Salomon, Phil M.

    1991-01-01

    High-current pulse-width-modulating driver for brushless dc motor features optical coupling of timing signals from low-current control circuitry to high-current motor-driving circuitry. Provides high electrical isolation of motor-power supply, helping to prevent fast, high-current motor-driving pulses from being coupled through power supplies into control circuitry, where they interfere with low-current control signals.

  10. Porous Alumina Films with Width-Controllable Alumina Stripes

    PubMed Central

    2010-01-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface. PMID:21170406

  11. Porous Alumina Films with Width-Controllable Alumina Stripes.

    PubMed

    Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

    2010-01-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface. PMID:21170406

  12. Porous Alumina Films with Width-Controllable Alumina Stripes

    NASA Astrophysics Data System (ADS)

    Huang, Kai; Huang, Shi-Ming; Pu, Lin; Shi, Yi; Wu, Zhi-Ming; Ji, Li; Kang, Jun-Yong

    2010-12-01

    Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  13. Evolution and diversity of subduction zones controlled by slab width.

    PubMed

    Schellart, W P; Freeman, J; Stegman, D R; Moresi, L; May, D

    2007-03-15

    Subducting slabs provide the main driving force for plate motion and flow in the Earth's mantle, and geodynamic, seismic and geochemical studies offer insight into slab dynamics and subduction-induced flow. Most previous geodynamic studies treat subduction zones as either infinite in trench-parallel extent (that is, two-dimensional) or finite in width but fixed in space. Subduction zones and their associated slabs are, however, limited in lateral extent (250-7,400 km) and their three-dimensional geometry evolves over time. Here we show that slab width controls two first-order features of plate tectonics-the curvature of subduction zones and their tendency to retreat backwards with time. Using three-dimensional numerical simulations of free subduction, we show that trench migration rate is inversely related to slab width and depends on proximity to a lateral slab edge. These results are consistent with retreat velocities observed globally, with maximum velocities (6-16 cm yr(-1)) only observed close to slab edges (<1,200 km), whereas far from edges (>2,000 km) retreat velocities are always slow (<2.0 cm yr(-1)). Models with narrow slabs (< or =1,500 km) retreat fast and develop a curved geometry, concave towards the mantle wedge side. Models with slabs intermediate in width ( approximately 2,000-3,000 km) are sublinear and retreat more slowly. Models with wide slabs (> or =4,000 km) are nearly stationary in the centre and develop a convex geometry, whereas trench retreat increases towards concave-shaped edges. Additionally, we identify periods (5-10 Myr) of slow trench advance at the centre of wide slabs. Such wide-slab behaviour may explain mountain building in the central Andes, as being a consequence of its tectonic setting, far from slab edges. PMID:17361181

  14. pacce: Perl algorithm to compute continuum and equivalent widths

    NASA Astrophysics Data System (ADS)

    Riffel, Rogério; Borges Vale, Tibério

    2011-08-01

    We present Perl Algorithm to Compute continuum and Equivalent Widths ( pacce). We describe the methods used in the computations and the requirements for its usage. We compare the measurements made with pacce and "manual" ones made using iraf splot task. These tests show that for synthetic simple stellar population (SSP) models the equivalent widths strengths are very similar (differences ≲0.2 Å) for both measurements. In real stellar spectra, the correlation between both values is still very good, but with differences of up to 0.5 Å. pacce is also able to determine mean continuum and continuum at line center values, which are helpful in stellar population studies. In addition, it is also able to compute the uncertainties in the equivalent widths using photon statistics. The code is made available for the community through the web at http://www.if.ufrgs.br/~riffel/software.html .

  15. New Measurement of the π0 Radiative Decay Width

    NASA Astrophysics Data System (ADS)

    Larin, I.; McNulty, D.; Clinton, E.; Ambrozewicz, P.; Lawrence, D.; Nakagawa, I.; Prok, Y.; Teymurazyan, A.; Ahmidouch, A.; Asratyan, A.; Baker, K.; Benton, L.; Bernstein, A. M.; Burkert, V.; Cole, P.; Collins, P.; Dale, D.; Danagoulian, S.; Davidenko, G.; Demirchyan, R.; Deur, A.; Dolgolenko, A.; Dzyubenko, G.; Ent, R.; Evdokimov, A.; Feng, J.; Gabrielyan, M.; Gan, L.; Gasparian, A.; Gevorkyan, S.; Glamazdin, A.; Goryachev, V.; Gyurjyan, V.; Hardy, K.; He, J.; Ito, M.; Jiang, L.; Kashy, D.; Khandaker, M.; Kingsberry, P.; Kolarkar, A.; Konchatnyi, M.; Korchin, A.; Korsch, W.; Kowalski, S.; Kubantsev, M.; Kubarovsky, V.; Li, X.; Martel, P.; Matveev, V.; Mecking, B.; Milbrath, B.; Minehart, R.; Miskimen, R.; Mochalov, V.; Mtingwa, S.; Overby, S.; Pasyuk, E.; Payen, M.; Pedroni, R.; Ritchie, B.; Rodrigues, T. E.; Salgado, C.; Shahinyan, A.; Sitnikov, A.; Sober, D.; Stepanyan, S.; Stephens, W.; Underwood, J.; Vasiliev, A.; Vishnyakov, V.; Wood, M.; Zhou, S.

    2011-04-01

    High precision measurements of the differential cross sections for π0 photoproduction at forward angles for two nuclei, C12 and Pb208, have been performed for incident photon energies of 4.9-5.5 GeV to extract the π0→γγ decay width. The experiment was done at Jefferson Lab using the Hall B photon tagger and a high-resolution multichannel calorimeter. The π0→γγ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is Γ(π0→γγ)=7.82±0.14(stat)±0.17(syst)eV. With the 2.8% total uncertainty, this result is a factor of 2.5 more precise than the current Particle Data Group average of this fundamental quantity, and it is consistent with current theoretical predictions.

  16. The lineshape problem in Doppler-width thermometry

    NASA Astrophysics Data System (ADS)

    Domenica De Vizia, Maria; Moretti, Luigi; Castrillo, Antonio; Fasci, Eugenio; Gianfrani, Livio

    2011-09-01

    Typically eliminated in any experiment of time and frequency metrology, the Doppler broadening effect can be regarded as a gift of nature for the purpose of measuring the thermodynamic temperature of a gaseous sample. Nevertheless, Doppler-width retrieval from highly-accurate absorption spectra is surely not an easy task as it requires an adequate knowledge of the lineshape function, accounting for the different mechanisms that contribute to the overall linewidth. Semiclassical theories provide several possibilities, more or less accurate in reproducing the observed profiles. Here, the influence of the choice of the lineshape model in Doppler-width thermometry is investigated in the physical situation of self-colliding ? O molecules. A large number of absorption profiles were simulated, using the uncorrelated version of the speed-dependent Galatry profile and setting different values for the gas pressure, the signal-to-noise ratio and the Dicke-narrowing parameter. Spectral analysis was performed by means of different models, in order to retrieve the zero-pressure value of the Doppler width. It turned out that precision and accuracy can be pushed to extreme levels provided that the signal-to-noise ratio is sufficiently high (namely, larger than 50,000) and that a speed-dependent lineshape model is used.

  17. Width-modulated square-wave pulses for ultrasound applications.

    PubMed

    Smith, Peter R; Cowell, David M J; Freear, Steven

    2013-11-01

    A method of output pressure control for ultrasound transducers using switched excitation is described. The method generates width-modulated square-wave pulse sequences that are suitable for driving ultrasound transducers using MOSFETs or similar devices. Sequences are encoded using an optimized level-shifted, carrier-comparison, pulse-width modulation (PWM) strategy derived from existing PWM theory, and modified specifically for ultrasound applications. The modifications are: a reduction in carrier frequency so that the smallest number of pulses are generated and minimal switching is necessary; alteration of a linear carrier form to follow a trigonometric relationship in accordance with the expected fundamental output; and application of frequency modulation to the carrier when generating frequency-modulated, amplitude- tapered signals. The PWM method permits control of output pressure for arbitrary waveform sequences at diagnostic frequencies (approximately 5 MHz) when sampled at 100 MHz, and is applicable to pulse shaping and array apodization. Arbitrary waveform generation capability is demonstrated in simulation using convolution with a transducer's impulse response, and experimentally with hydrophone measurement. Benefits in coded imaging are demonstrated when compared with fixed-width square-wave (pseudo-chirp) excitation in coded imaging, including reduction in image artifacts and peak side-lobe levels for two cases, showing 10 and 8 dB reduction in peak side-lobe level experimentally, compared with 11 and 7 dB reduction in simulation. In all cases, the experimental observations correlate strongly with simulated data. PMID:24158282

  18. Combining LEP and LHC to bound the Higgs width

    NASA Astrophysics Data System (ADS)

    Englert, Christoph; McCullough, Matthew; Spannowsky, Michael

    2016-01-01

    The correlation of on- and off-shell Higgs boson production at the LHC in gg →h* → ZZ has been used to bound the Higgs width. We propose an alternative complementary constraint which is only possible through the combination of LEP and LHC measurements. Precision electroweak measurements at LEP allow for the determination of indirect constraints on Higgs couplings to vector bosons by considering one-loop processes involving virtual Higgs exchange. As the indirect constraint is model dependent we will consider two specific models which modify the Higgs couplings and width, and our results will apply specifically to these models. By combining these LEP constraints with current LHC 8 TeV Higgs measurements a stronger limit on the Higgs width can be achieved than with LHC data alone. Looking to the future, a more robust constraint can be achieved by correlating LEP measurements with WBF Higgs production followed by Higgs decays to WW and ZZ. We will discuss the model dependence of this method in comparison to other proposed methods.

  19. Predictors of the peak width for networks with exponential links

    USGS Publications Warehouse

    Troutman, B.M.; Karlinger, M.R.

    1989-01-01

    We investigate optimal predictors of the peak (S) and distance to peak (T) of the width function of drainage networks under the assumption that the networks are topologically random with independent and exponentially distributed link lengths. Analytical results are derived using the fact that, under these assumptions, the width function is a homogeneous Markov birth-death process. In particular, exact expressions are derived for the asymptotic conditional expectations of S and T given network magnitude N and given mainstream length H. In addition, a simulation study is performed to examine various predictors of S and T, including N, H, and basin morphometric properties; non-asymptotic conditional expectations and variances are estimated. The best single predictor of S is N, of T is H, and of the scaled peak (S divided by the area under the width function) is H. Finally, expressions tested on a set of drainage basins from the state of Wyoming perform reasonably well in predicting S and T despite probable violations of the original assumptions. ?? 1989 Springer-Verlag.

  20. A New Measurement of the Pi0 Radiative Decay Width

    SciTech Connect

    Larin, I; Clinton, E; Ambrozewicz, P; Lawrence, D; Nakagawa, I; Prok, Y; Teymurazyan, A; Ahmidouch, A; Baker, K; Benton, L; Bernstein, A M; Burkert, V; Cole, P; Collins, P; Dale, D; Danagoulian, S; Davidenko, G; Demirchyan, R; Deur, A; Dolgolenko, A; Dzyubenko, Georgiy; Ent, R; Evdokimov, A; Feng, J; Gabrielyan, M; Gan, L; Gasparian, A; Gevorkyan, S; Glamazdin, A; Goryachev, V; Gyurjyan, V; Hardy, K; He, J; Ito, M; Jiang, L; Kashy, D; Khandaker, M; Kingsberry, P; Kolarkar, A; Konchatnyi, M; Korsch, W; Kowalski, S; Kubantsev, M; Kubarovsky, V; Li, X; Martel, P; Mecking, B; Milbrath, B; Minehart, R; Miskimen, R; Mochalov, V; Mtingwa, S; Overby, S; Pasyuk, E; Payen, M; Pedroni, R; Ritchie, B; Rodrigues, T E; Salgado, C; Shahinyan, A; Sitnikov, A; Sober, D; Stepanyan, S; Stephens, W; Underwood, J; Vishnyakov, V; Wood, M

    2011-04-01

    High precision measurements of the differential cross sections for $\\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^{208}$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\\pi^0 \\to \\gamma\\gamma}$ decay width. The experiment was done at Jefferson Lab using the Hall~B photon tagger and a high-resolution multichannel calorimeter. The ${\\pi^0 \\to \\gamma\\gamma}$ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is $\\Gamma{(\\pi^0 \\to \\gamma\\gamma)} = 7.82 \\pm 0.14 ~({\\rm stat.}) \\pm 0.17 ~({\\rm syst.}) ~{\\rm eV}$. With the 2.8\\% total uncertainty, this result is a factor of 2.5 more precise than the current PDG average of this fundamental quantity and it is consistent with current theoretical predictions.

  1. Sliding mode pulse-width modulation technique for direct torque controlled induction motor drive

    NASA Astrophysics Data System (ADS)

    Bounadja, M.; Belarbi, A. W.; Belmadani, B.

    2010-05-01

    This paper presents a novel pulse-width modulation technique based sliding mode approach for direct torque control of an induction machine drive. Methodology begins with a sliding mode control of machine's torque and stator flux to generate the reference voltage vector and to reduce parameters sensitivity. Then, the switching control of the three-phase inverter is developed using sliding mode concept to make the system tracking reference voltage inputs. The main features of the proposed methodologies are the high tracking accuracy and the much easier implementation compared to the space vector modulation. Simulations are carried out to confirm the effectiveness of proposed control algorithms.

  2. Lyman-alpha observations of Comet Kohoutek 1973 XII with Copernicus

    NASA Technical Reports Server (NTRS)

    Drake, J. F.; Jenkins, E. B.; Bertaux, J. L.; Festou, M.; Keller, H. U.

    1976-01-01

    Comet Kohoutek 1973 XII was observed with a telescope-spectrometer on the Copernicus satellite on six occasions over a 1-month period starting on January 29, 1974. Positive detection of the cometary Ly-alpha emission profile was obtained on January 29 and February 2. Earlier observations of the geocoronal Ly-alpha emission profile allowed an instrumental intensity calibration and confirmation of the computed instrumental profile for an extended source at the Ly-alpha wavelength. After allowing for broadening by the instrument, a hydrogen-outflow velocity of about 10.6 km/s is derived from the width of the Ly-alpha emission on January 29. The intensity calibration combined with an appropriate cometary model led to cometary water-production rates for January 29 and February 2. Only upper limits were obtained for Ly-alpha on and after February 14. Searches for OH and D led to negative results.

  3. Development and identification of monoclonal antibodies against meso-Tetra (alpha,alpha,alpha,alpha,-O-phenylacetamide benzene) porphyrin.

    PubMed

    Wang, Fengyang; Huang, Xueying; Du, Li; Li, Weiguo; Qi, Chao

    2007-04-01

    The small molecule meso-Tetra (alpha,alpha,alpha,alpha-o-phenylacetamide benzene) porphyrin was synthesized through the condensation of o-nitrobenzaldehyde and pyrrole followed by reduction of the meso-tetra (o-nitrophenyl) porphyrin. The small molecule, without carrier, was used as complete antigen to immunize BALB/ C mice. Spleen cells producing high titer antibody were removed and fused with myeloma cells of SP2/0 origin. Using a conventional immunization protocol, stable murine monoclonal antibodies (MAbs) producing cell lines to meso-Tetra (alpha,alpha,alpha,alpha-o-phenylacetamide benzene) porphyrin 1F2 were obtained. Subclass determination showed that the clones produce IgG2a types of MAbs. The analytical results of HPLC and MALDI/TOFMS suggest that the purity of MAb 1F2 is 100%, and MAb 1F2 has a relative molecular weight of 156678.8 Da. Our results demonstrated that small molecule meso-Tetra (alpha,alpha,alpha,alpha-o-phenylacetamide benzene) porphyrin, as semiantigen without carrier, can elicit the formation of MAbs. PMID:17451352

  4. Vasodilating effect of norethisterone and its 5 alpha metabolites: a novel nongenomic action.

    PubMed

    Perusquía, Mercedes; Villalón, Carlos M; Navarrete, Erika; García, Gustavo A; Pérez-Palacios, Gregorio; Lemus, Ana E

    2003-08-15

    Estrogens are generally administered in hormone replacement therapy in combination with synthetic progestins. Studies of cardiovascular risk factors in postmenopausal women have shown a variety of responses according to the molecular structure of the progestin used in hormone replacement therapy schemes. The present study sets out to determine the vasoactive effects of norethisterone and its 5alpha-dihydro (5alpha-norethisterone) and -tetrahydro (3alpha,5alpha-norethisterone and 3beta,5alpha-norethisterone) metabolites in isolated precontracted rat thoracic aorta. The addition of norethisterone and 3alpha,5alpha-norethisterone in rat aorta exhibited a potent, concentration-response inhibition of noradrenaline-induced contraction, while 5alpha- and 3beta,5alpha-norethisterone had very little, if any, vasorelaxing effect. Relaxation to norethisterone and 3alpha,5alpha-norethisterone had very rapid time-courses and it was neither affected by the absence of endothelium nor by the inhibitor of nitric oxide synthase, Nomega-nitro-L-arginine methyl ester (L-NAME). The addition of specific anti-androgen, anti-progestin and anti-estrogen compounds and protein synthesis inhibitors did not preclude the vasorelaxing effect of norethisterone and its 3alpha,5alpha-reduced metabolite. The results strongly suggest that these effects are not mediated by nuclear sex steroid hormone receptors. The overall data document a novel nongenomic endothelium-independent vasorelaxing action of a 19-nor synthetic progestin and one of its A-ring-reduced derivatives. PMID:12954372

  5. Maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width groups

    PubMed Central

    Shahid, Fazal; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli

    2015-01-01

    Objective: To investigate the maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width (intercanine, interpremolar, and intermolar) groups. Materials and Methods: The calculated sample size was 128 subjects. The crown width/height, arch length, arch perimeter, and arch width of the maxilla and mandible were obtained via digital calliper (Mitutoyo, Japan). A total of 4325 variables were measured. The sex differences in the crown width and height were evaluated. Analysis of variance was applied to evaluate the differences between arch length, arch perimeter, and arch width groups. Results: Males had significantly larger mean values for crown width and height than females (P ≤ 0.05) for maxillary and mandibular arches, both. There were no significant differences observed for the crown width/height ratio in various arch length, arch perimeter, and arch width (intercanine, interpremolar, and intermolar) groups (P ≤ 0.05) in maxilla and mandible, both. Conclusions: Our results indicate sexual disparities in the crown width and height. Crown width and height has no significant relation to various arch length, arch perimeter, and arch width groups of maxilla and mandible. Thus, it may be helpful for orthodontic and prosthodontic case investigations and comprehensive management. PMID:26929686

  6. Skylab observations of H I Lyman-alpha

    NASA Technical Reports Server (NTRS)

    Roussel-Dupre, D.

    1982-01-01

    The H I Lyman-alpha profiles obtained with the Skylab SO82-B spectrograph at spectral and spatial resolutions of 60 mA and 2 arcsec x 60 arcsec are presented. Profile variations are illustrated from center to limb, at different heights above the limb, and over a cell and network boundary. The Lyman-alpha core exhibits weak or no limb darkening, whereas the line wings show weak limb darkening. Above the limb, the Lyman-alpha core integrated intensity and line width remain in essence constant up to plus 12 arcsec and may result from resonance scattering of chromospheric radiation by coronal neutral hydrogen or from spicules. On the disk, intensities in the line core are seen as correlating well with the H-alpha network; however, the Lyman-alpha wing intensities are found to correlate better with the transition region lines. The average of profiles acquired over the cell and network region is found to be similar to profiles obtained in the cell.

  7. Poster — Thur Eve — 02: Measurement of CT radiation profile width using Fuji CR imaging plate raw data

    SciTech Connect

    Bjarnason, T A; Yang, C J

    2014-08-15

    Measuring the CT collimation width and assessing the shape of the overall profile is a relatively straightforward quality control (QC) measure that impacts both image quality and patient dose, and is often required at acceptance and routine testing. Most CT facilities have access to computed radiography (CR) systems, so performing CT collimation profile assessments using CR plates requires no additional equipment. Previous studies have shown how to effectively use CR plates to measure the radiation profile width. However, a major limitation of the previous work is that the full dynamic range of CR detector plates are not used, since the CR processing technology reduces the dynamic range of the DICOM output to 2{sup 10}, requiring the sensitivity and latitude settings of CR reader to be adjusted to prevent clipping of the CT profile data. Such adjustments to CR readers unnecessarily complicate the QC procedure. These clipping artefacts hinder the ability to accurately assess CT collimation width because the full-width at half maximum value of the penumbras are not properly determined if the maximum dose of the profile is not available. Furthermore, any inconsistencies in the radiation profile shape are lost if the profile plateau is clipped off. In this work we developed an opensource Matlab script for straightforward CT profile width measurements using raw CR data that also allows assessment of the profile shape without clipping, and applied this approach during CT QC.

  8. ERR{alpha} regulates osteoblastic and adipogenic differentiation of mouse bone marrow mesenchymal stem cells

    SciTech Connect

    Rajalin, Ann-Marie; Pollock, Hanna; Aarnisalo, Piia

    2010-05-28

    The orphan nuclear receptor estrogen-related receptor-{alpha} (ERR{alpha}) has been reported to have both a positive and a negative regulatory role in osteoblastic and adipocytic differentiation. We have studied the role of ERR{alpha} in osteoblastic and adipogenic differentiation of mesenchymal stem cells. Bone marrow mesenchymal stem cells were isolated from ERR{alpha} deficient mice and their differentiation capacities were compared to that of the wild-type cells. ERR{alpha} deficient cultures displayed reduced cellular proliferation, osteoblastic differentiation, and mineralization. In the complementary experiment, overexpression of ERR{alpha} in MC3T3-E1 cells increased the expression of osteoblastic markers and mineralization. Alterations in the expression of bone sialoprotein (BSP) may at least partially explain the effects on mineralization as BSP expression was reduced in ERR{alpha} deficient MSCs and enhanced upon ERR{alpha} overexpression in MC3T3-E1 cells. Furthermore, a luciferase reporter construct driven by the BSP promoter was efficiently transactivated by ERR{alpha}. Under adipogenic conditions, ERR{alpha} deficient cultures displayed reduced adipocytic differentiation. Our data thus propose a positive role for ERR{alpha} in osteoblastic and adipocytic differentiation. The variability in the results yielded in the different studies implies that ERR{alpha} may play different roles in bone under different physiological conditions.

  9. Numerical investigation of edge plasma phenomena in an enhanced D-alpha discharge at Alcator C-Mod: Parallel heat flux and quasi-coherent edge oscillations

    SciTech Connect

    Russell, D. A.; D'Ippolito, D. A.; Myra, J. R.; LaBombard, B.; Terry, J. L.; Zweben, S. J.

    2012-08-15

    Reduced-model scrape-off layer turbulence (SOLT) simulations of an enhanced D-alpha (EDA) H-mode shot observed in the Alcator C-Mod tokamak were conducted to compare with observed variations in the scrape-off-layer (SOL) width of the parallel heat flux profile. In particular, the role of the competition between sheath- and conduction-limited parallel heat fluxes in determining that width was studied for the turbulent SOL plasma that emerged from the simulations. The SOL width decreases with increasing input power and with increasing separatrix temperature in both the experiment and the simulation, consistent with the strong temperature dependence of the parallel heat flux in balance with the perpendicular transport by turbulence and blobs. The particularly strong temperature dependence observed in the case analyzed is attributed to the fact that these simulations produce SOL plasmas which are in the conduction-limited regime for the parallel heat flux. A persistent quasi-coherent (QC) mode dominates the SOLT simulations and bears considerable resemblance to the QC mode observed in C-Mod EDA operation. The SOLT QC mode consists of nonlinearly saturated wave-fronts located just inside the separatrix that are convected poloidally by the mean flow, continuously transporting particles and energy and intermittently emitting blobs into the SOL.

  10. Leptonic widths of heavy quarkonia: QCD/NRQCD matching for the electromagnetic current at O(alpha_s v^2)

    NASA Astrophysics Data System (ADS)

    von Hippel, Georg

    2006-12-01

    We construct the S-wave part of the electromagnetic vector annihilation current to O(αs v2 ), where v is the non-relativistic quark velocity, for heavy quarks whose dynamics are described by the ¯ NRQCD action on the lattice. The NRQCD vector current for QQ annihilation is expressed as a linear combination of lattice operators with quantum numbers L = 0, J P = 1- , and the coefficients are determined by matching to the corresponding continuum current in QCD to O(v2 ) at one- loop. The annihilation channel gives a complex amplitude with Coulomb-exchange and infrared singularities, making a careful choice for the contours of integration and infrared subtraction functions in the numerical integration necessary. An automated vertex generation program written in Python is employed, allowing us to use a realistic NRQCD action and an improved gluon lattice action; a change in the definition of either action is easily accommodated in this procedure. The final result is applicable to simulations of electromagnetic decays of heavy quarkonia, notably the ϒ meson.

  11. Performance of an in-situ alpha spectrometer.

    PubMed

    Pöllänen, R

    2016-03-01

    Equipment was recently developed for detecting alpha particles from flat and smooth surfaces with good energy resolution at ambient air pressure. In this work, the detection efficiencies were determined using different extended-area sources emitting alpha and beta radiation and a mixed nuclide point source emitting alpha radiation. Beta particles are of importance because they can also be detected. Counts originating from alpha and beta particles are mainly at different energies, which make their separation possible. An efficiency of 0.14 was determined for an extended-area (>30cm(2)) homogeneous source emitting alpha radiation at the energy of 5-6MeV, whereas for the beta emitters the efficiencies were 0.07-0.19 depending on the beta-particle emission energies. The use of a collimator reduces the detection efficiencies by a factor of up to ten. PMID:26688356

  12. Beam width evolution of astigmatic hollow Gaussian beams in highly nonlocal nonlinear media

    NASA Astrophysics Data System (ADS)

    Yang, Zhen-Feng; Jiang, Xue-Song; Yang, Zhen-Jun; Li, Jian-Xing; Zhang, Shu-Min

    We investigate the beam width evolution of astigmatic hollow Gaussian beams propagating in highly nonlocal nonlinear media. The input-power-induced different evolutions of the beam width are illustrated: (i) the beam widths in two transverse directions are compressed or broadened at the same time; (ii) the beam width in one transverse direction keeps invariant, and the other is compressed or broadened; (iii) furthermore, the beam width in one transverse direction is compressed, whereas it in the other transverse direction is broadened.

  13. Earthquake supercycle in subduction zones controlled by the width of the seismogenic zone

    NASA Astrophysics Data System (ADS)

    Herrendoerfer, R.; Dalguer, L. A.; van Dinther, Y.; Gerya, T.

    2015-12-01

    Supercycles describe a long-term cluster of differently-sized megathrust earthquakes that consist of partial ruptures leading up to the final complete failure of a subduction zone segment. We recognize that supercycles are suggested to occur in those subduction zones (Sumatra, Japan, S-Chile, N-Central Chile, Colombia-Ecuador) for which the estimated seismogenic zone downdip width is larger than average (111 km). Here we provide an explanation for this potential link between the seismogenic zone downdip width and supercycles. We use a two-dimensional, continuum-based seismo-mechanical model, which was recently validated through a comparison against scaled analogue subduction experiments. The setup consists of an upper plate represented by a visco-elastic wedge, which is underthrusted by a rigid plate. The megathrust is simulated by a layer governed by slip-rate dependent friction, in which the velocity-weakening seismogenic zone extends over a certain width and transitions up-and downdip to velocity-strengthening regions. In our simulations, the first megathrust events in a supercycle generally rupture only the outermost parts of the seismogenic zone. These sub-critical and pulse-like ruptures are stopped due to a large excess of strength over stress, which leads to a transfer of stresses towards the centre of the seismogenic zone. In addition to the continued tectonic loading, they thereby gradually reduce the strength excess so that the largest megathrust events finally rupture the entire seismogenic zone in a crack-like manner and release most of the accumulated stress. A greater downdip width increases the average strength excess and thus favours supercycles over ordinary cycles of only similarly sized complete ruptures. We conclude that such stress evolution along the dip of a wide seismogenic zone is the simplest mechanism governing supercycles. Additional a priori complexities, like previously suggested structural or frictional heterogeneities are not

  14. Radial Regge trajectories and leptonic widths of the isovector mesons

    NASA Astrophysics Data System (ADS)

    Badalian, A. M.; Bakker, B. L. G.

    2016-04-01

    It is shown that two physical phenomena are important for high excitations: (i) the screening of the universal gluon-exchange potential and (ii) the flattening of the confining potential owing to creation of quark loops, and both effects are determined quantitatively. Taking the first effect into account, we predict the masses of the ground states with l =0 , 1, 2 in agreement with experiment. The flattening effect ensures the observed linear behavior of the radial Regge trajectories M2(n )=m02+nrμ2 GeV2, where the slope μ2 is very sensitive to the parameter γ , which determines the weakening of the string tension σ (r ) at large distances. For the ρ trajectory the linear behavior starts with nr=1 and the values μ2=1.40 (2 ) GeV2 for γ =0.40 and μ2=1.34 (1 ) GeV2 for γ =0.45 are obtained. For the excited states the leptonic widths Γee(ρ (775 ))=7.0 (3 ) keV , Γee(ρ (1450 ))=1.7 (1 ) keV , Γee(ρ (1900 ))=1.0 (1 ) keV , Γee(ρ (2150 ))=0.7 (1 ) keV , and Γee(1 3D1)=0.26 (5 ) keV are calculated, if these states are considered as purely q q ¯ states. The width Γee(ρ (1700 )) increases if ρ (1700 ) is mixed with the 2 3S1 state, giving for a mixing angle θ =21 ° almost equal widths: Γee(ρ (1700 ))=0.75 (6 ) keV and Γee(1450 )=1.0 (1 ) keV .

  15. Axial couplings and strong decay widths of heavy hadrons

    SciTech Connect

    William Detmold, C.-J. David Lin, Stefan Meinel

    2012-04-01

    We calculate the axial couplings of mesons and baryons containing a heavy quark in the static limit using lattice QCD. These couplings determine the leading interactions in heavy hadron chiral perturbation theory and are central quantities in heavy quark physics, as they control strong decay widths and the light-quark mass dependence of heavy hadron observables. Our analysis makes use of lattice data at six different pion masses, 227 MeV < m{sub {pi}} < 352 MeV, two lattice spacings, a = 0.085, 0.112 fm, and a volume of (2.7 fm){sup 3}. Our results for the axial couplings are g{sub 1} = 0.449(51), g{sub 2} = 0.84(20), and g{sub 3} = 0.71(13), where g{sub 1} governs the interaction between heavy-light mesons and pions and g{sub 2,3} are similar couplings between heavy-light baryons and pions. Using our lattice result for g{sub 3}, and constraining 1/m{sub Q} corrections in the strong decay widths with experimental data for {Sigma}{sub c}{sup (*)} decays, we obtain {Gamma}[{Sigma}{sub b}{sup (*)} {yields} {Lambda}{sub b} {pi}{sup {+-}}] = 4.2(1.0), 4.8(1.1), 7.3(1.6), 7.8(1.8) MeV for the {Sigma}{sub b}{sup +}, {Sigma}{sub b}{sup -}, {Sigma}{sub b}{sup *+}, {Sigma}{sub b}{sup *-} initial states, respectively. We also derive upper bounds on the widths of the {Xi}{sub b}{sup prime(*)} baryons.

  16. High resolution alpha particle spectrometry through collimation

    NASA Astrophysics Data System (ADS)

    Park, Seunghoon; Kwak, Sung-Woo; Kang, Han-Byeol

    2015-06-01

    Alpha particle spectrometry with collimation is a useful method for identifying nuclear materials among various nuclides. A mesh type collimator reduces the low energy tail and broadened energy distribution by cutting off particles with a low incidence angle. The relation between the resolution and the counting efficiency can be investigated by changing a ratio of the mesh hole diameter and the collimator thickness. Through collimation, a target particle can be distinguished by a PIPS® detector under a mixture of various nuclides.

  17. Strong-interaction shifts and widths of kaonic helium isotopes

    NASA Astrophysics Data System (ADS)

    SIDDHARTA Collaboration; Ishiwatari, T.; Bazzi, M.; Beer, G.; Bombelli, L.; Bragadireanu, A. M.; Cargnelli, M.; Curceanu (Petrascu), C.; d'Uffizi, A.; Fiorini, C.; Frizzi, T.; Ghio, F.; Guaraldo, C.; Hayano, R. S.; Iliescu, M.; Iwasaki, M.; Kienle, P.; Levi Sandri, P.; Longoni, A.; Marton, J.; Okada, S.; Pietreanu, D.; Ponta, T.; Rizzo, A.; Romero Vidal, A.; Sbardella, E.; Scordo, A.; Shi, H.; Sirghi, D. L.; Sirghi, F.; Tatsuno, H.; Tudorache, A.; Tudorache, V.; Vazquez Doce, O.; Widmann, E.; Wünschek, B.; Zmeskal, J.

    2013-09-01

    The kaonic 3He and 4He 3d→2p transitions in gaseous targets were observed by the SIDDHARTA experiment. The X-ray energies of these transitions were measured with large-area silicon-drift detectors using the timing information of the K+K- pairs produced by the DAΦNE e+e- collider. The strong-interaction shifts and widths both of the kaonic 3He and 4He 2p states were determined, which are much smaller than the results obtained by the previous experiments. The "kaonic helium puzzle" (a discrepancy between theory and experiment) was now resolved.

  18. Strong-interaction shifts and widths of kaonic helium isotopes

    NASA Astrophysics Data System (ADS)

    Ishiwatari, T.; Bazzi, M.; Beer, G.; Bombelli, L.; Bragadireanu, A. M.; Cargnelli, M.; Curceanu (Petrascu), C.; D'Uffizi, A.; Fiorini, C.; Frizzi, T.; Ghio, F.; Guaraldo, C.; Hayano, R. S.; Iliescu, M.; Iwasaki, M.; Kienle, P.; Levi Sandri, P.; Longoni, A.; Marton, J.; Okada, S.; Pietreanu, D.; Ponta, T.; Rizzo, A.; Romero Vidal, A.; Sbardella, E.; Scordo, A.; Shi, H.; Sirghi, D. L.; Sirghi, F.; Tatsuno, H.; Tudorache, A.; Tudorache, V.; Vazquez Doce, O.; Widmann, E.; Wünschek, B.; Zmeskal, J.; Siddharta Collaboration

    2013-09-01

    The kaonic 3He and 4He 3d→2p transitions in gaseous targets were observed by the SIDDHARTA experiment. The X-ray energies of these transitions were measured with large-area silicon-drift detectors using the timing information of the K+K- pairs produced by the DAΦNE e+e- collider. The strong-interaction shifts and widths both of the kaonic 3He and 4He 2p states were determined, which are much smaller than the results obtained by the previous experiments. The “kaonic helium puzzle” (a discrepancy between theory and experiment) was now resolved.

  19. Comment on ``Casimir energies with finite-width mirrors''

    NASA Astrophysics Data System (ADS)

    Fialkovsky, Ignat; Pis'Mak, Yuriy; Markov, Vladimir

    2009-01-01

    We comment on a recent publication by Fosco, Lombardo, and Mazzitelli on Casimir energies for material slabs (“finite-width mirrors”) and report a discrepancy between results obtained there for a single mirror and some previous calculations. We provide a simple consistency check which proves that the method used by Fosco et al. is not reliable when applied to approximations of piecewise constant profile of the mirror. We also present an alternative method for calculation of the Casimir energy in such systems based on earlier work of ours. Our results coincide both with perturbation theory and with some older and more recent calculations, but differ from those of Fosco et al.

  20. Measurement of peak discharge at width contractions by indirect methods

    USGS Publications Warehouse

    Matthai, Howard Frederick

    1967-01-01

    This chapter describes procedures for measuring peak discharges using open-channel width contractions. Field and office procedures limited to this method are described. The discharge equation based on the continuity and energy equations between an approach cross section and the contracted section under a bridge or contraction is given. Contractions are classified into four geometric types. Discharge coefficients and computation procedures are given with a complete facsimile example of computation of a contracted-opening measurement. Additional procedures are given for multiple-opening contractions.

  1. A high-precision pulse-width modulator source.

    SciTech Connect

    Lenkszus, F.; Laird, R.

    1999-09-30

    A novel high-resolution pulse-width modulator (PWM) is being developed for a new digital regulator for the Advanced Photon Source power converters. The circuit features 82-ps setability over an 80-{micro}s range. Our application requires a 50-{micro}s fill-scale range; therefore the 82-ps setability is equivalent to better than 19 bits. The circuit is presently implemented as a VME module and is an integral part of the digital regulator prototype. The design concept and performance results will be presented.

  2. Auger width of metastable states in antiprotonic helium

    SciTech Connect

    Revai, J.; Kruppa, A.T.

    1998-01-01

    Auger decay probabilities of metastable states in antiprotonic helium are derived using a minimal extension of the existing bound-state wave functions to account for the electron continuum. Calculations were performed for the Born-Oppenheimer wave functions of Shimamura [Phys. Rev. A {bold 46}, 3776 (1992)] and the variational wave functions of Korobov [Phys. Rev. A {bold 54}, 1749 (1996)]. Our results suggest that the overall accuracy of the Auger widths calculated from the presently available bound-state wave functions is not sufficient. {copyright} {ital 1998} {ital The American Physical Society}

  3. Collisional width of giant resonances and interplay with Landau damping

    SciTech Connect

    Bonasera, A.; Burgio, G. F.; Di Toro, M.; Wolter, H. H.

    1989-06-01

    We present a semiclassical method to calculate the widths of giant resonances. We solve a mean-field kinetic equation (Vlasov equation) with collision terms treated within the relaxation time approximation to construct a damped strength distribution for collective motions. The relaxation time is evaluated from the time evolution of distortions in the nucleon momentum distribution using a test-particle approach. The importance of an energy dependent nucleon-nucleon cross section is stressed. Results are shown for isoscalar giant quadrupole and octupole motions. A quite important interplay between self-consistent (Landau) and collisional damping is revealed.

  4. Distribution of narrow-width magnetic anomalies in Antarctica

    USGS Publications Warehouse

    Behrendt, John C.

    1964-01-01

    Data for aeromagnetic profiles obtained in Antarctica during the 1963-64 austral summer were used together with earlier results to construct a map showing the areal distribution of narrow-width magnetic anomalies. Numerous anomalies are associated with known volcanic mountains in western Antarctica. A large area of few anomalies is probably a result of an extension of the thick metasedimentary section observed in the Ellsworth Mountains. Portions of the Trans-Antarctic Mountains have associated anomalies which are probably caused by late Cenozoic volcanic rocks.

  5. {lambda}(1520) {yields} {lambda}{gamma} Radiative-Decay Width

    SciTech Connect

    Vavilov, D.V.; Antipov, Yu.M.; Artamonov, A.V.; Batarin, V.A.; Victorov, V.A.; Golovkin, S.V.; Gorin, Yu.P.; Eroshin, O.V.; Kozhevnikov, A.P.; Konstantinov, A.S.; Kubarovsky, V.P.; Kurshetsov, V.F.; Landsberg, L.G.; Leontiev, V.M.; Molchanov, V.V.; Mukhin, V.A.; Patalakha, D.I.; Petrenko, S.V.; Petrukhin, A.I.; Kolganov, V.Z.

    2005-03-01

    The radiative decay {lambda}(1520) {yields} {lambda}{gamma} was recorded in the exclusive reaction p + N {yields} {lambda}(1520)K{sup +} + N at the SPHINX facility. The branching ratio for this decay and the corresponding partial width were found to be, respectively, Br[{lambda}(1520) {yields} {lambda}{gamma}] = (1.02 {+-} 0.21) x 10{sup -2} and {gamma}[{lambda}(1520) {yields} {lambda}{gamma}] = 159 {+-} 35 keV (the quoted errors are purely statistical, the systematic errors being within 15%)

  6. Effect of stance width on multidirectional postural responses

    NASA Technical Reports Server (NTRS)

    Henry, S. M.; Fung, J.; Horak, F. B.; Peterson, B. W. (Principal Investigator)

    2001-01-01

    The effect of stance width on postural responses to 12 different directions of surface translations was examined. Postural responses were characterized by recording 11 lower limb and trunk muscles, body kinematics, and forces exerted under each foot of 7 healthy subjects while they were subjected to horizontal surface translations in 12 different, randomly presented directions. A quasi-static approach of force analysis was done, examining force integrals in three different epochs (background, passive, and active periods). The latency and amplitude of muscle responses were quantified for each direction, and muscle tuning curves were used to determine the spatial activation patterns for each muscle. The results demonstrate that the horizontal force constraint exerted at the ground was lessened in the wide, compared with narrow, stance for humans, a similar finding to that reported by Macpherson for cats. Despite more trunk displacement in narrow stance, there were no significant changes in body center of mass (CoM) displacement due to large changes in center of pressure (CoP), especially in response to lateral translations. Electromyographic (EMG) magnitude decreased for all directions in wide stance, particularly for the more proximal muscles, whereas latencies remained the same from narrow to wide stance. Equilibrium control in narrow stance was more of an active postural strategy that included regulating the loading/unloading of the limbs and the direction of horizontal force vectors. In wide stance, equilibrium control relied more on an increase in passive stiffness resulting from changes in limb geometry. The selective latency modulation of the proximal muscles with translation direction suggests that the trunk was being actively controlled in all directions. The similar EMG latencies for both narrow and wide stance, with modulation of only the muscle activation magnitude as stance width changed, suggest that the same postural synergy was only slightly modified

  7. Stark Widths of Spectral Lines of Neutral Neon

    NASA Astrophysics Data System (ADS)

    Dimitrijević, Milan S.; Simić, Zoran; Kovačević, Andjelka; Valjarević, Aleksandar; Sahal-Bréchot, Sylvie

    2015-12-01

    In order to complete Stark broadening data for Ne I spectral lines which are needed for analysis of stellar atmospheres, collisional widths and shifts (the so-called Stark broadening parameters) of 29 isolated spectral lines of neutral neon have been determined within the impact semiclassical perturbation method. Calculations have been performed for the broadening by collisions with electrons, protons and ionized helium for astrophysical applications, and for collisions with ionized neon and argon for laboratory plasma diagnostics. The shifts have been compared with existing experimental values. The obtained data will be included in the STARK-B database, which is a part of the Virtual Atomic and Molecular Data Center - VAMDC.

  8. Degravitation of the cosmological constant and graviton width

    SciTech Connect

    Dvali, Gia; Hofmann, Stefan; Khoury, Justin

    2007-10-15

    We study the possibility of decoupling gravity from the vacuum energy. This is effectively equivalent to promoting Newton's constant to a high-pass filter that degravitates sources of characteristic wavelength larger than a certain macroscopic (super) horizon scale L. We study the underlying physics and the consistency of this phenomenon. In particular, the absence of ghosts, already at the linear level, implies that in any such theory the graviton should either have a mass 1/L, or be a resonance of similar width. This has profound physical implications for the degravitation idea.

  9. Heavy-light charm mesons spectroscopy and decay widths

    NASA Astrophysics Data System (ADS)

    Upadhyay, Alka; Batra, Meenakshi; Gupta, Pallavi

    2016-05-01

    We present the mass formula for heavy-light charm meson at one loop, using heavy quark effective theory. Formulating an effective Lagrangian, the masses of the ground state heavy mesons have been studied in the heavy quark limit, including leading corrections from finite heavy quark masses and nonzero light quark masses, using a constrained fit for the eight equations with 11 parameters including three coupling constants g, h, and g^' }. Masses determined using this approach are fitted to the experimentally known decay widths to estimate the strong coupling constants, showing a better match with available theoretical and experimental data.

  10. The flow around an inclined flat plate of finite width

    NASA Astrophysics Data System (ADS)

    Narumi, A.; Kato, S.; Terada, K.; Izumi, R.; Yanase, T.

    1985-07-01

    The flow around an inclined finite width plate was experimentally studied using oil film and oil point techniques. At the front surface, leading edge separation does not occur and the flow becomes more laminar than in the case with angle of incidence zero, though the flow yaws towards the side edge and separates from it. The flow at the back surface is characterized by a side edge vortex, a flow separated near the side edge of the leading edge, and a flow separated at the middle of the leading edge. The characteristics of these flows are discussed.

  11. Lactation is disrupted by alpha-lactalbumin deficiency and can be restored by human alpha-lactalbumin gene replacement in mice.

    PubMed Central

    Stacey, A; Schnieke, A; Kerr, M; Scott, A; McKee, C; Cottingham, I; Binas, B; Wilde, C; Colman, A

    1995-01-01

    Mice carrying either a deletion of the murine alpha-lactalbumin (alpha-lac) gene (null allele) or its replacement by the human alpha-lac gene (humanized allele) have been generated by gene targeting. Homozygous null females are alpha-lac-deficient, produce reduced amounts of thickened milk containing little or no lactose, and cannot sustain their offspring. This provides definitive evidence that alpha-lac is required for lactose synthesis and that lactose is important for milk production. Females homozygous for the humanized allele lactate normally, indicating that human alpha-lac can replace murine alpha-lac. Mouse and human alpha-lac expression was compared in mice heterozygous for the humanized allele. The human gene expressed approximately 15-fold greater mRNA and approximately 14-fold greater protein than the mouse, indicating that the major determinants of human alpha-lac expression are close to, or within, the human gene and that the mouse locus does not exert a negative influence on alpha-lac expression. Variations in alpha-lac expression levels in nondeficient mice did not affect milk lactose concentration, but the volume of milk increased slightly in mice homozygous for the humanized allele. These variations demonstrated that alpha-lac expression in mice is gene dosage dependent. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:7708733

  12. Binding of receptor-recognized forms of alpha2-macroglobulin to the alpha2-macroglobulin signaling receptor activates phosphatidylinositol 3-kinase.

    PubMed

    Misra, U K; Pizzo, S V

    1998-05-29

    Ligation of the alpha2-macroglobulin (alpha2M) signaling receptor by receptor-recognized forms of alpha2M (alpha2M*) initiates mitogenesis secondary to increased intracellular Ca2+. We report here that ligation of the alpha2M signaling receptor also causes a 1. 5-2.5-fold increase in wortmannin-sensitive phosphatidylinositol 3-kinase (PI3K) activity as measured by the quantitation of phosphatidylinositol 3,4,5-trisphosphate (PIP3). PIP3 formation was alpha2M* concentration-dependent with a maximal response at approximately 50 pM ligand concentration. The peak formation of PIP3 occurred at 10 min of incubation. The alpha2M receptor binding fragment mutant K1370R which binds to the alpha2M signaling receptor activating the signaling cascade, increased PIP3 formation by 2-fold. The mutant K1374A, which binds very poorly to the alpha2M signaling receptor, did not cause any increase in PIP3 formation. alpha2M*-induced DNA synthesis was inhibited by wortmannin. 1, 2Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acetoxymethylester a chelator of intracellular Ca2+, drastically reduced alpha2M*-induced increases in PIP3 formation. We conclude that PI3K is involved in alpha2M*-induced mitogenesis in macrophages and intracellular Ca2+ plays a role in PI3K activation. PMID:9593670

  13. New hybrid reverse differential pulse position width modulation scheme for wireless optical communication

    NASA Astrophysics Data System (ADS)

    Liao, Renbo; Liu, Hongzhan; Qiao, Yaojun

    2014-05-01

    In order to improve the power efficiency and reduce the packet error rate of reverse differential pulse position modulation (RDPPM) for wireless optical communication (WOC), a hybrid reverse differential pulse position width modulation (RDPPWM) scheme is proposed, based on RDPPM and reverse pulse width modulation. Subsequently, the symbol structure of RDPPWM is briefly analyzed, and its performance is compared with that of other modulation schemes in terms of average transmitted power, bandwidth requirement, and packet error rate over ideal additive white Gaussian noise (AWGN) channels. Based on the given model, the simulation results show that the proposed modulation scheme has the advantages of improving the power efficiency and reducing the bandwidth requirement. Moreover, in terms of error probability performance, RDPPWM can achieve a much lower packet error rate than that of RDPPM. For example, at the same received signal power of -28 dBm, the packet error rate of RDPPWM can decrease to 2.6×10-12, while that of RDPPM is 2.2×10. Furthermore, RDPPWM does not need symbol synchronization at the receiving end. These considerations make RDPPWM a favorable candidate to select as the modulation scheme in the WOC systems.

  14. Nucleon thermal width owing to pion-baryon loops and its contributions to shear viscosity

    NASA Astrophysics Data System (ADS)

    Ghosh, Sabyasachi

    2014-08-01

    In real-time thermal field theory, the standard expression of shear viscosity for nucleonic constituents is derived from the two-point function of nucleonic viscous stress tensors at finite temperature and density. The finite thermal width or Landau damping is traditionally included in the nucleon propagators. This thermal width is calculated from the in-medium self-energy of nucleons for different possible pion-baryon loops. The dynamical part of nucleon-pion-baryon interactions are accounted for by the effective Lagrangian densities of standard hadronic model. The shear viscosity to entropy density ratio of the nucleonic component decreases with the temperature and increases with the nucleon chemical potential. However, adding the contribution of the pionic component, the total viscosity to entropy density ratio also reduces with the nucleon chemical potential when the mixing effect between pion and nucleon components in the mixed gas is considered. Within the hadronic domain, the viscosity to entropy density ratio of the nuclear matter gradually reduces as temperature and nucleon chemical potential increase and therefore the nuclear matter is approaching the (nearly) perfect-fluid state.

  15. Ablation of SM22alpha decreases contractility and actin contents of mouse vascular smooth muscle.

    PubMed

    Zeidan, Asad; Swärd, Karl; Nordström, Ina; Ekblad, Eva; Zhang, Janet C L; Parmacek, Michael S; Hellstrand, Per

    2004-03-26

    The actin-binding protein SM22alpha marks contractile differentiation in smooth muscle, but its function is unknown. We tested its role in arterial contractility and stretch-sensitive vascular protein synthesis. Active stress in depolarised mesenteric resistance arteries and portal veins was reduced by 40% in SM22alpha(-/-) mice. Passive and active arterial circumference-force relationships were shifted leftwards, whereas alpha(1)-adrenergic responses were increased. Actin contents were 10-25% lower in vessels from SM22alpha(-/-) mice, but protein composition was otherwise similar. Synthesis of SM22alpha, calponin and alpha-actin, but not beta-actin, was sensitive to stretch. Ablation of SM22alpha did not affect stretch sensitivity of any of these proteins. Thus, SM22alpha plays a role in contractility, possibly by affecting actin filament organisation. PMID:15044015

  16. The structure of cell wall alpha-glucan from fission yeast.

    PubMed

    Grün, Christian H; Hochstenbach, Frans; Humbel, Bruno M; Verkleij, Arie J; Sietsma, J Hans; Klis, Frans M; Kamerling, Johannis P; Vliegenthart, Johannes F G

    2005-03-01

    Morphology and structural integrity of fungal cells depend on cell wall polysaccharides. The chemical structure and biosynthesis of two types of these polysaccharides, chitin and (1-->3)-beta-glucan, have been studied extensively, whereas little is known about alpha-glucan. Here we describe the chemical structure of alpha-glucan isolated from wild-type and mutant cell walls of the fission yeast Schizosaccharomyces pombe. Wild-type alpha-glucan was found to consist of a single population of linear glucose polymers, approximately 260 residues in length. These glucose polymers were composed of two interconnected linear chains, each consisting of approximately 120 (1-->3)-linked alpha-d-glucose residues and some (1-->4)-linked alpha-D-glucose residues at the reducing end. By contrast, alpha-glucan of an alpha-glucan synthase mutant with an aberrant cell morphology and reduced alpha-glucan levels consisted of a single chain only. We propose that alpha-glucan biosynthesis involves an ordered series of events, whereby two alpha-glucan chains are coupled to create mature cell wall alpha-glucan. This mature form of cell wall alpha-glucan is essential for fission-yeast morphogenesis. PMID:15470229

  17. Longitudinal wave motion in width-constrained auxetic plates

    NASA Astrophysics Data System (ADS)

    Lim, Teik-Cheng

    2016-05-01

    This paper investigates the longitudinal wave velocity in auxetic plates in comparison to conventional ones, in which the plate is constrained from motion in the width direction. By taking into account the thickness change of the plate and its corresponding change in density, the developed wave velocity is casted not only as a function of Young’s modulus and density, but also in terms of Poisson’s ratio and longitudinal strain. Results show that density and thickness variations compensate for one another when the Poisson’s ratio is positive, but add up when the Poisson’s ratio is negative. Results also reveal that the classical model of longitudinal wave velocity for the plate is accurate when the Poisson’s ratio is about 1/3; at this Poisson’s ratio the influence from density and thickness variations cancel each other. Comparison between the current corrected model and the density-corrected Rayleigh–Lamb model reveals a number of consistent trends, while the discrepancies are elucidated. If the plate material possesses a negative Poisson’s ratio, the deviation of the actual wave velocity from the classical model becomes significant; auxeticity suppresses and enhances the wave velocity in compressive and tensile impacts, respectively. Hence the use of the corrected model is proposed when predicting longitudinal waves in width-constrained auxetic plates, and auxetic materials can be harnessed for effectively controlling wave velocities in thin-walled structures.

  18. Is biologic width of anterior and posterior teeth similar?

    PubMed

    Rasouli Ghahroudi, Amir Alireza; Khorsand, Afshin; Yaghobee, Siamak; Haghighati, Farideh

    2014-01-01

    The biologic width (BW) includes attached epithelial cells and connective tissue attachment complex being very important in the periodontal health during prosthetic treatments as invading this zone can cause bone resorption and gingival recession. The present study investigated biologic width values in the normal periodontium in anterior and posterior teeth. 30 patients that referred from restorative department to periodontics department of Tehran University of medical sciences who need crown lengthening procedure on their teeth with no history of orthodontic, prosthodontic and periodontal treatment were randomly enrolled in this cross-sectional trial. Sulcus depths (SD) as well as the distance between free gingival margin and the bone crest (FB) of anterior and posterior teeth were measured by UNC-15 probe and compared. periodontium thickness was also assessed. The data were subjected to Student t test. Mean BW in the 43 anterior and 47 posterior teeth was measured and not significantly different (1.4651±0.39 mm vs. 1.6312±0.49 mm) was observed; however, BW was significantly more in the teeth with thick periodontium compared to those with thin periodontium (1.703±0.5 vs. 1.408±0.35; P=0.002). BW not only is different in individuals but also could be dissimilar in different teeth and should be calculated independently prior to restorative treatments. PMID:25325207

  19. Fractal Reference Signals in Pulse-Width Modulation

    NASA Technical Reports Server (NTRS)

    Lurie, Boris; Lurie, Helen

    2005-01-01

    A report proposes the use of waveforms having fractal shapes reminiscent of sawteeth (in contradistinction to conventional regular sawtooth waveforms) as reference signals for pulse-width modulation in control systems for thrusters of spacecraft flying in formation. Fractal reference signals may also be attractive in some terrestrial control systems - especially those in which pulse-width modulation is used for precise control of electric motors. The report asserts that the use of fractal reference signals would enable the synchronous control of several variables of a spacecraft formation, such that consumption of propellant would be minimized, intervals between thruster firings would be long (as preferred for performing scientific observations), and delays in controlling large-thrust maneuvers for retargeting would be minimized. The report further asserts that whereas different controllers would be needed for different modes of operation if conventional pulsewidth modulation were used, the use of fractal reference signals would enable the same controller to function nearly optimally in all regimes of operation, so that only this one controller would be needed.

  20. QSO Narrow [OIII] Line Width and Host Galaxy Luminosity

    NASA Astrophysics Data System (ADS)

    Bonning, E. W.; Shields, G. A.; Salviander, S.

    2004-05-01

    Established correlations between galaxy bulge luminosity L, black hole mass MBH, and stellar velocity dispersion sigma in galaxies suggest a close relationship between the growth of supermassive black holes and their host galaxies. Measurements of the MBH - sigma relationship as a function of cosmic time may shed light on the origin of this relationship. One approach is to derive MBH and sigma from the widths of QSO broad and narrow lines, respectively (Shields et al. 2003, ApJ, 583, 124; Nelson 2000, ApJ, 544, L91). We investigate the utility of using the velocity of the narrow line emitting gas as a surrogate for stellar velocity dispersion in QSOs by examining host magnitudes and [OIII] line widths for low redshift QSOs. For our limited range of L, the increase in sigma with L predicted by the Faber-Jackson relation is substantially obscured by scatter. However, sigma([O III]) is consistent in the mean with host galaxy luminosity. EWB is a NASA GSRP fellow. GAS and SS are supported under Texas Advanced Research Program grant 003658-0177-2001 and NSF grant AST-0098594.

  1. Ly{alpha} COOLING EMISSION FROM GALAXY FORMATION

    SciTech Connect

    Faucher-Giguere, Claude-Andre; Keres, Dusan; Dijkstra, Mark; Hernquist, Lars; Zaldarriaga, Matias

    2010-12-10

    such dense gas yields lower luminosities by up to one to two orders of magnitude at high masses, making it difficult to explain the observed Ly{alpha} blobs with pure cooling. Resonant scattering produces diffuse Ly{alpha} halos, even for centrally concentrated emission, and broad double peaked line profiles. In particular, the emergent line widths are in general not representative of the velocity dispersion within galactic halos and cannot be directly used to infer host halo masses.

  2. Proceedings, High-Precision $\\alpha_s$ Measurements from LHC to FCC-ee

    SciTech Connect

    d'Enterria, David; Skands, Peter Z.

    2015-01-01

    This document provides a writeup of all contributions to the workshop on "High precision measurements of $\\alpha_s$: From LHC to FCC-ee" held at CERN, Oct. 12--13, 2015. The workshop explored in depth the latest developments on the determination of the QCD coupling $\\alpha_s$ from 15 methods where high precision measurements are (or will be) available. Those include low-energy observables: (i) lattice QCD, (ii) pion decay factor, (iii) quarkonia and (iv) $\\tau$ decays, (v) soft parton-to-hadron fragmentation functions, as well as high-energy observables: (vi) global fits of parton distribution functions, (vii) hard parton-to-hadron fragmentation functions, (viii) jets in $e^\\pm$p DIS and $\\gamma$-p photoproduction, (ix) photon structure function in $\\gamma$-$\\gamma$, (x) event shapes and (xi) jet cross sections in $e^+e^-$ collisions, (xii) W boson and (xiii) Z boson decays, and (xiv) jets and (xv) top-quark cross sections in proton-(anti)proton collisions. The current status of the theoretical and experimental uncertainties associated to each extraction method, the improvements expected from LHC data in the coming years, and future perspectives achievable in $e^+e^-$ collisions at the Future Circular Collider (FCC-ee) with $\\cal{O}$(1--100 ab$^{-1}$) integrated luminosities yielding 10$^{12}$ Z bosons and jets, and 10$^{8}$ W bosons and $\\tau$ leptons, are thoroughly reviewed. The current uncertainty of the (preliminary) 2015 strong coupling world-average value, $\\alpha_s(m_Z)$ = 0.1177 $\\pm$ 0.0013, is about 1\\%. Some participants believed this may be reduced by a factor of three in the near future by including novel high-precision observables, although this opinion was not universally shared. At the FCC-ee facility, a factor of ten reduction in the $\\alpha_s$ uncertainty should be possible, mostly thanks to the huge Z and W data samples available.

  3. The Statistical Distributions of Landslide Length to Width Ratios

    NASA Astrophysics Data System (ADS)

    Taylor, F. E.; Malamud, B. D.

    2012-04-01

    There has been considerable effort in analysis of the frequency-size statistics of landslide areas and volumes, yet less attention to the statistics of landslide shape. Here, we use two substantially complete triggered event landslide area inventories to quantify how length (L) to width (W) ratios vary as a function of landslide area. The first inventory is 11,111 landslides triggered by the 17 January 1994 Northridge earthquake in California and the second inventory is 9594 landslides triggered by heavy rainfall from Hurricane Mitch in Guatemala in late October and early November 1998. We assume that all landslide shapes can be abstracted to a rectangle L - W , and find that the ratio of the long side (L) to the short side (W) of this shape varies with landslide area. The length-to-width ratio, L/W , is calculated by two methods which are considered separately: (i) from a quadratic equation using the given inventory landslide area and perimeter; (ii) applying a 'bounding box' where L is the longest linear axis of the landslide and W perpendicular to this. For each of the two methods, the statistical distribution using Maximum likelihood estimation of L/W values were then considered for eight landslide area categories (bins) increasing logarithmically: AL = 100-199, 200-399, 400-799, 800-1599, 1600-3199, 3200-6399, 6400-12,799, 12,800-25,600 m2. We find that for each landslide area bin considered, the probability density function of L/W follows reasonably well a three-parameter inverse gamma distribution; this distribution has a power-law decay with exponent (ρ + 1) for medium and large landslide areas and an exponential rollover for small areas. There is a relatively low probability of landslides where L/W = 1 (i.e. a square), with the maximum probability of occurrence for L/W = 1.8 to 2.2 for landside areas in categories 100-199, ..., 3200-6399 m2, and L/W = 3 and 7 for the two largest landslide area categories. For the three landslide area categories between

  4. Device for uniform. cap alpha. irradiation of solid powders

    SciTech Connect

    Orlenev, P.O.; Mel'nikov, P.V.

    1988-08-01

    A device for uniform irradiation of solid powders by alpha particles is described. Uniformity of irradiation is achieved by regular stirring of the specimen on the surface of the alpha source. Polonium 210 serves as the alpha source. A method is described that reduces by a factor of approx. 3 the error in determination of the dose absorbed by a powdered specimen and eliminates irradiation nonuniformity. The effect of heterogeneity saturation on measurements of the radiation properties of the electron-hole centers was checked by study of the dose dependencies of Al/sup 3+/-O/sup -/ and D' centers in quartz.

  5. Alpha-mannosidosis

    PubMed Central

    Malm, Dag; Nilssen, Øivind

    2008-01-01

    Alpha-mannosidosis is an inherited lysosomal storage disorder characterized by immune deficiency, facial and skeletal abnormalities, hearing impairment, and intellectual disability. It occurs in approximately 1 of 500,000 live births. The children are often born apparently normal, and their condition worsens progressively. Some children are born with ankle equinus or develop hydrocephalus in the first year of life. Main features are immune deficiency (manifested by recurrent infections, especially in the first decade of life), skeletal abnormalities (mild-to-moderate dysostosis multiplex, scoliosis and deformation of the sternum), hearing impairment (moderate-to-severe sensorineural hearing loss), gradual impairment of mental functions and speech, and often, periods of psychosis. Associated motor function disturbances include muscular weakness, joint abnormalities and ataxia. The facial trait include large head with prominent forehead, rounded eyebrows, flattened nasal bridge, macroglossia, widely spaced teeth, and prognathism. Slight strabismus is common. The clinical variability is significant, representing a continuum in severity. The disorder is caused by lysosomal alpha-mannosidase deficiency. Alpha-mannosidosis is inherited in an autosomal recessive fashion and is caused by mutations in the MAN2B1 gene located on chromosome 19 (19 p13.2-q12). Diagnosis is made by measuring acid alpha-mannosidase activity in leukocytes or other nucleated cells and can be confirmed by genetic testing. Elevated urinary secretion of mannose-rich oligosaccharides is suggestive, but not diagnostic. Differential diagnoses are mainly the other lysosomal storage diseases like the mucopolysaccharidoses. Genetic counseling should be given to explain the nature of the disease and to detect carriers. Antenatal diagnosis is possible, based on both biochemical and genetic methods. The management should be pro-active, preventing complications and treating manifestations. Infections must be

  6. Molecular design of hybrid tumour necrosis factor alpha with polyethylene glycol increases its anti-tumour potency.

    PubMed Central

    Tsutsumi, Y.; Kihira, T.; Tsunoda, S.; Kanamori, T.; Nakagawa, S.; Mayumi, T.

    1995-01-01

    This study was conducted to increase the anti-tumour potency and reduce the toxic side-effects of tumour necrosis factor alpha (TNF-alpha). Natural human TNF-alpha was chemically conjugated with monomethoxy polyethylene glycol (PEG) using succinimidyl coupling of lysine amino groups of TNF-alpha. The number-average molecular weight of PEG-modified TNF-alpha (PEG-TNF-alpha) increased with an increase in the reaction time and the initial molar ratio of PEG relative to TNF-alpha. The resulting modified TNF-alpha was separated into fractions of various molecular weights. The specific activity of separated PEG-TNF-alpha s relative to that of native TNF-alpha gradually decreased with an increase in the degree of PEG modification, but the plasma half-life was drastically increased with the increase in molecular weight of modified TNF-alpha. PEG-TNF-alpha s, in which 29% and 56% of lysine residues were coupled to PEG, had anti-tumour activity approximately 4 and 100 times greater than unmodified TNF-alpha in the murine Meth-A fibrosarcoma model. Extensive PEG modification did not increase its in vivo activity. A high dose of unmodified TNF-alpha induced toxic side-effects, but these were not observed with the modified TNF-alpha s. Optimal PEG modification of TNF-alpha markedly increased its bioavailability and may facilitate its potential anti-tumour therapeutic use. PMID:7734321

  7. Cultured Ito cells of rat liver express the alpha 2-macroglobulin gene.

    PubMed

    Andus, T; Ramadori, G; Heinrich, P C; Knittel, T; Meyer zum Büschenfelde, K H

    1987-11-01

    Ito cells were isolated from rat liver and kept in culture for up to 13 days. The capability of the Ito cells to synthesize alpha 2-macroglobulin was analyzed at different times after isolation and by pulse-chase experiments. Newly synthesized alpha 2-macroglobulin was determined by immunoprecipitation followed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and fluorography. alpha 2-Macroglobulin synthesis was hardly detectable in Ito cells and their media 3 days after plating. However, 5-11 days after the isolation of the cells, increasing amounts of alpha 2-macroglobulin were synthesized. The results of pulse-chase experiments performed on day 7 showed that radioactively labeled alpha 2-macroglobulin decreased in the intracellular compartment and increased in the culture medium. alpha 2-Macroglobulin was identified by immunoprecipitation and sodium dodecyl sulfate/polyacrylamide gel electrophoresis under reducing and non-reducing conditions. Furthermore, when unlabeled alpha 2-macroglobulin was added during the immunoprecipitation, a competition was observed. Incubation of pancreatic elastase with culture medium of rat Ito cells or rat hepatocytes led to the same cleavage products as found with alpha 2-macroglobulin. alpha 2-Macroglobulin-specific mRNA could be demonstrated by Northern blot analysis of total RNA extracted from rat Ito cells. Under the conditions where alpha 2-macroglobulin was synthesized in Ito cells, no synthesis of alpha 1-macroglobulin, alpha 1-inhibitor 3, alpha 1-proteinase inhibitor, alpha 1-acid glycoprotein, alpha 1-acute-phase globulin (T-kininogen) and albumin could be demonstrated. It is concluded that alpha 2-macroglobulin is a true secretory protein of rat Ito cells in culture. This could be of importance for collagen metabolism in liver diseases. PMID:2444437

  8. Improvement of deoxidization efficiency of nitric monoxide by shortening pulse width of semiconductor opening switch pulse power generator

    NASA Astrophysics Data System (ADS)

    Kakuta, Takatoshi; Yagi, Ippei; Takaki, Koichi

    2015-01-01

    The deoxidization efficiency of nitric monoxide (NO) was improved by shortening the pulse width of the voltage applied to a corona reactor. The deoxidization efficiency of NO was evaluated as the NO removal efficiency in nitrogen (N2) gas containing 200 ppm NO. The corona reactor had a coaxial geometry and consisted of center high-voltage wire and outer grounded cylinder electrodes. A nanosecond high-voltage pulse was generated using an inductive energy storage pulse power circuit with a semiconductor opening switch and was applied to the center wire electrode in the corona reactor. Fast recovery diodes were utilized as a semiconductor opening switch. The pulse width of the applied voltage was reduced from 21 to 14 ns with the arrester connected in parallel to the reactor. The energy efficiency for NO removal was improved from 8.2 to 35.7 g kW-1 h-1 with the arrester connected. The pulse width was also reduced to 8 ns by optimizing the circuit parameters. It was confirmed from observation with an intensified charge-coupled device (ICCD) camera that the streamer corona discharge transited to a glowlike discharge after the streamer propagated from the center wire electrode to the outer cylinder electrode. The duration of the glowlike phase was reduced with the arrester connected. The energy consumed in the glowlike phase was also reduced from 15.7 to 4.6 mJ with the arrester connected.

  9. AN ATLAS OF z = 5.7 AND z = 6.5 Ly{alpha} EMITTERS ,

    SciTech Connect

    Hu, E. M.; Cowie, L. L.; Barger, A. J.; Capak, P.; Kakazu, Y.; Trouille, L. E-mail: cowie@ifa.hawaii.ed E-mail: trouille@astro.wisc.ed E-mail: kakazu@astro.caltech.ed

    2010-12-10

    We present an atlas of 88 z {approx} 5.7 and 30 z {approx} 6.5 Ly{alpha} emitters obtained from a wide-field narrowband survey. We combined deep narrowband imaging in 120 A bandpass filters centered at 8150 A and 9140 A with deep BVRIz broadband imaging to select high-redshift galaxy candidates over an area of 4180 arcmin{sup 2}. The goal was to obtain a uniform selection of comparable depth over the seven targeted fields in the two filters. For the GOODS-North region of the Hubble Deep Field-North field, we also selected candidates using a 120 A filter centered at 9210 A. We made spectroscopic observations with Keck DEIMOS of nearly all the candidates to obtain the final sample of Ly{alpha} emitters. At the 3.3 A resolution of the DEIMOS observations the asymmetric profile for Ly{alpha} emission can be clearly seen in the spectra of nearly all the galaxies. We show that the spectral profiles are surprisingly similar for many of the galaxies and that the composite spectral profiles are nearly identical at z = 5.7 and z = 6.5. We analyze the distributions of line widths and Ly{alpha} equivalent widths and find that the lines are marginally narrower at the higher redshift, with median values of 0.77 A at z = 6.5 and 0.92 A at z = 5.7. The line widths have a dependence on the Ly{alpha} luminosity of the form {approx}L {sup 0.3}{sub {alpha}}. We compare the surface densities and the luminosity functions at the two redshifts and find that there is a multiplicative factor of two decrease in the number density of bright Ly{alpha} emitters from z = 5.7 to z = 6.5, while the characteristic luminosity is unchanged.

  10. Alpha particle effects on the internal kink modes

    SciTech Connect

    Wu, Yanlin; Cheng, C.Z.

    1994-08-01

    The {alpha}-particle effects on the internal kink mode stability are studied. Finite Grad-Shafranov Shift, plasma {beta}, and plasma shape can significantly enhance the trapped particle drift reversal domain in pitch angle space and reduce average magnetic drift frequency. The drift reversal effect on the ideal kink mode is small, but the {beta}{sub {alpha}} threshold for the fishbone mode can be much lower than previously predicted. In addition, the ion diamagnetic drift has a stronger destabilizing effect.

  11. Proteinaceous alpha-amylase inhibitors.

    PubMed

    Svensson, Birte; Fukuda, Kenji; Nielsen, Peter K; Bønsager, Birgit C

    2004-02-12

    Proteins that inhibit alpha-amylases have been isolated from plants and microorganisms. These inhibitors can have natural roles in the control of endogenous alpha-amylase activity or in defence against pathogens and pests; certain inhibitors are reported to be antinutritional factors. The alpha-amylase inhibitors belong to seven different protein structural families, most of which also contain evolutionary related proteins without inhibitory activity. Two families include bifunctional inhibitors acting both on alpha-amylases and proteases. High-resolution structures are available of target alpha-amylases in complex with inhibitors from five families. These structures indicate major diversity but also some similarity in the structural basis of alpha-amylase inhibition. Mutational analysis of the mechanism of inhibition was performed in a few cases and various protein engineering and biotechnological approaches have been outlined for exploitation of the inhibitory function. PMID:14871655

  12. Long range alpha particle detector

    DOEpatents

    MacArthur, Duncan W.; Wolf, Michael A.; McAtee, James L.; Unruh, Wesley P.; Cucchiara, Alfred L.; Huchton, Roger L.

    1993-01-01

    An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

  13. Long range alpha particle detector

    DOEpatents

    MacArthur, D.W.; Wolf, M.A.; McAtee, J.L.; Unruh, W.P.; Cucchiara, A.L.; Huchton, R.L.

    1993-02-02

    An alpha particle detector capable of detecting alpha radiation from distant sources. In one embodiment, a high voltage is generated in a first electrically conductive mesh while a fan draws air containing air molecules ionized by alpha particles through an air passage and across a second electrically conductive mesh. The current in the second electrically conductive mesh can be detected and used for measurement or alarm. The detector can be used for area, personnel and equipment monitoring.

  14. STELLAR LOCI. I. METALLICITY DEPENDENCE AND INTRINSIC WIDTHS

    SciTech Connect

    Yuan, Haibo; Liu, Xiaowei; Xiang, Maosheng; Huang, Yang; Chen, Bingqiu E-mail: x.liu@pku.edu.cn

    2015-02-01

    Stellar loci are widely used for selection of interesting outliers, reddening determinations, and calibrations. However, until now, the dependence of stellar loci on metallicity has not been fully explored, and their intrinsic widths are unclear. In this paper, by combining the spectroscopic and recalibrated imaging data of the Sloan Digital Sky Survey (SDSS) Stripe 82, we have built a large, clean sample of dwarf stars with accurate colors and well-determined metallicities to investigate the metallicity dependence and intrinsic widths of the SDSS stellar loci. Typically, 1 dex decrease in metallicity causes 0.20 and 0.02 mag decrease in colors u – g and g – r and 0.02 and 0.02 mag increase in colors r – i and i – z, respectively. The variations are larger for metal-rich stars than for metal-poor ones, and larger for F/G/K stars than for A/M ones. Using the sample, we have performed two-dimensional polynomial fitting to the u – g, g – r, r – i, and i – z colors as a function of color g – i and metallicity [Fe/H]. The residuals, at the level of 0.029, 0.008, 0.008, and 0.011 mag for the u – g, g – r, r – i, and i – z colors, respectively, can be fully accounted for by the photometric errors and metallicity uncertainties, suggesting that the intrinsic widths of the loci are at maximum a few millimagnitudes. The residual distributions are asymmetric, revealing that a significant fraction of stars are binaries. In a companion paper, we will present an unbiased estimate of the binary fraction for field stars. Other potential applications of the metallicity-dependent stellar loci are briefly discussed.

  15. Invariantly propagating dissolution fingers in finite-width systems

    NASA Astrophysics Data System (ADS)

    Dutka, Filip; Szymczak, Piotr

    2016-04-01

    Dissolution fingers are formed in porous medium due to positive feedback between transport of reactant and chemical reactions [1-4]. We investigate two-dimensional semi-infinite systems, with constant width W in one direction. In numerical simulations we solve the Darcy flow problem combined with advection-dispersion-reaction equation for the solute transport to track the evolving shapes of the fingers and concentration of reactant in the system. We find the stationary, invariantly propagating finger shapes for different widths of the system, flow and reaction rates. Shape of the reaction front, turns out to be controlled by two dimensionless numbers - the (width-based) Péclet number PeW = vW/Dφ0 and Damköhler number DaW = ksW/v, where k is the reaction rate, s - specific reactive surface area, v - characteristic flow rate, D - diffusion coefficient of the solute, and φ0 - initial porosity of the rock matrix. Depending on PeW and DaW stationary shapes can be divided into seperate classes, e.g. parabolic-like and needle-like structures, which can be inferred from theoretical predictions. In addition we determine velocity of propagating fingers in time and concentration of reagent in the system. Our simulations are compared with natural forms (solution pipes). P. Ortoleva, J. Chadam, E. Merino, and A. Sen, Geochemical self-organization II: the reactive-infiltration instability, Am. J. Sci, 287, 1008-1040 (1987). M. L. Hoefner, and H. S. Fogler. Pore evolution and channel formation during flow and reaction in porous media, AIChE Journal 34, 45-54 (1988). C. E. Cohen, D. Ding, M. Quintard, and B. Bazin, From pore scale to wellbore scale: impact of geometry on wormhole growth in carbonate acidization, Chemical Engineering Science 63, 3088-3099 (2008). P. Szymczak and A. J. C. Ladd, Reactive-infiltration nstabilities in rocks. Part II: Dissolution of a porous matrix, J. Fluid Mech. 738, 591-630 (2014).

  16. ISS Update: Alpha Magnetic Spectrometer

    NASA Video Gallery

    NASA Public Affairs Officer Kelly Humphries interviews Trent Martin, Johnson Space Center project manager for the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. Questions...

  17. Determination of alpha-tocopherol and alpha-tocopherylquinone in rat tissues and plasma by high-performance liquid chromatography with electrochemical detection.

    PubMed

    Kanazawa, H; Miyata, C; Nagata, Y; Urano, S; Matsushima, Y

    2000-10-01

    Alpha-tocopherol and alpha-tocopherylquinone in rat tissues and plasma were determined simultaneously by using high-performance liquid chromatography-electrochemical detection (HPLC-ED) with dual electrodes in the series mode. Biological samples were saponified in the presence of a mixture of butylated hydroxytoluene, ascorbic acid, and pyrogallol and then extracted with hexane. The compounds were separated on a C18 column using a mobile phase containing 95% methanol and 0.05 M sodium perchlorate as the supporting electrolyte. After HPLC separation, alpha-tocopherylquinone was first reduced at an upstream electrode at -500 mV Both alpha-tocopherol and the reduction product of alpha-tocopherylquinone were then oxidized downstream at +600 mV. Only the downstream electrode current was monitored for the determination. Linearity of the standard curves was obtained over the range 5-30 pmol for alpha-tocopherol and alpha-tocopherylquinone. Minimum detectable quantities (S/N of 3) were 0.25 pmol for alpha-tocopherol and 0.31 pmol for alpha-tocopherylquinone. The method was applied to analysis of the contents of alpha-tocopherol and alpha-tocopherylquinone in rat tissues and plasma. By hyperoxia, the content of alpha-tocopherol was decreased remarkably in lung, and in contrast, the contents of alpha-tocopherylquinone were increased in all tissues studied with the exception of plasma, though the content of alpha-tocopherylquinone in normal rats is quite small. The technique is particularly useful in the quantitation of the oxidation of alpha-tocopherol in biological samples. PMID:11045451

  18. Mouse liver testosterone 15 alpha-hydroxylase (cytochrome P-450(15) alpha). Purification, regioselectivity, stereospecificity, and sex-dependent expression.

    PubMed

    Harada, N; Negishi, M

    1984-01-25

    Testosterone 15 alpha-hydroxylase (cytochrome P-450(15) alpha) was purified from female 129/J mouse liver microsomes based on its specific activities in the eluates from the columns of octylamino-Sepharose 4B, hydroxylapatite, DEAE-Bio-Gel A, and CM52 chromatography. The 15 alpha-hydroxylation activity was five times higher in female than in male 129/J mouse liver microsomes. The specific cytochrome P-450 content of purified P-450(15) alpha fraction was 14.5 nmol/mg of protein. The Soret peak of the reduced cytochrome P-450-CO complex was 451 nm. The apparent subunit molecular weight of P-450(15) alpha was 48,000, and the protein appeared as only one major band on sodium dodecyl sulfate-polyacrylamide gels. The specific activity of testosterone 15 alpha-hydroxylation reconstituted with the purified P-450(15) alpha was 94 nmol/min/nmol of cytochrome P-450 and 1349 nmol/min/mg of protein, and these were about 65- and 1000-fold higher, respectively, than the activity of solubilized microsomes. The purified P-450(15) alpha exhibited high regioselectivity and stereospecificity for testosterone hydroxylation. More than 95% of the testosterone metabolites formed by the purified P-450(15) alpha was 15 alpha-hydroxytestosterone. Virtually 100% of mouse liver microsomal testosterone 15 alpha-hydroxylation activity can be accounted for by the purified P-450(15) alpha. The P-450(15) alpha fraction was able to catalyze benzphetamine N-demethylation, 7-ethoxycoumarin O-de-ethylation, aniline 4-hydroxylation, benzo(alpha)pyrene 3-hydroxylation, acetanilide 4-hydroxylation, and lauric acid (11 + 12)-hydroxylation at various turnover rates, indicating broad substrate specificity of the P-450(15) alpha for the oxidations of xenobiotics. This is in sharp contrast to high regioselectivity and stereospecificity for testosterone hydroxylation. PMID:6420405

  19. A SUCCESSFUL BROADBAND SURVEY FOR GIANT Ly{alpha} NEBULAE. II. SPECTROSCOPIC CONFIRMATION

    SciTech Connect

    Prescott, Moire K. M.; Dey, Arjun; Jannuzi, Buell T.

    2013-01-01

    Using a systematic broadband search technique, we have carried out a survey for large Ly{alpha} nebulae (or Ly{alpha} {sup b}lobs{sup )} at 2 {approx}< z {approx}< 3 within 8.5 deg{sup 2} of the NOAO Deep Wide-Field Survey Booetes field, corresponding to a total survey comoving volume of Almost-Equal-To 10{sup 8} h {sup -3} {sub 70} Mpc{sup 3}. Here, we present our spectroscopic observations of candidate giant Ly{alpha} nebulae. Of 26 candidates targeted, 5 were confirmed to have Ly{alpha} emission at 1.7 {approx}< z {approx}< 2.7, 4 of which were new discoveries. The confirmed Ly{alpha} nebulae span a range of Ly{alpha} equivalent widths, colors, sizes, and line ratios, and most show spatially extended continuum emission. The remaining candidates did not reveal any strong emission lines, but instead exhibit featureless, diffuse, blue continuum spectra. Their nature remains mysterious, but we speculate that some of these might be Ly{alpha} nebulae lying within the redshift desert (i.e., 1.2 {approx}< z {approx}< 1.6). Our spectroscopic follow-up confirms the power of using deep broadband imaging to search for the bright end of the Ly{alpha} nebula population across enormous comoving volumes.

  20. Effect of vision and stance width on human body motion when standing: implications for afferent control of lateral sway.

    PubMed Central

    Day, B L; Steiger, M J; Thompson, P D; Marsden, C D

    1993-01-01

    1. Measurements of human upright body movements in three dimensions have been made on thirty-five male subjects attempting to stand still with various stance widths and with eyes closed or open. Body motion was inferred from movements of eight markers fixed to specific sites on the body from the shoulders to the ankles. Motion of these markers was recorded together with motion of the point of application of the resultant of the ground reaction forces (centre of pressure). 2. The speed of the body (average from eight sites) was increased by closing the eyes or narrowing the stance width and there was an interaction between these two factors such that vision reduced body speed more effectively when the feet were closer together. Similar relationships were found for components of velocity both in the frontal and sagittal planes although stance width exerted a much greater influence on the lateral velocity component. 3. Fluctuations in position of the body were also increased by eye closure or narrowing of stance width. Again, the effect of stance width was more potent for lateral than for anteroposterior movements. In contrast to the velocity measurements, there was no interaction between vision and stance width. 4. There was a progressive increase in the amplitude of position and velocity fluctuations from markers placed higher on the body. The fluctuations in the position of the centre of pressure were similar in magnitude to those of the markers placed near the hip. The fluctuations in velocity of centre of pressure, however, were greater than of any site on the body. 5. Analysis of the amplitude of angular motion between adjacent straight line segments joining the markers suggests that the inverted pendulum model of body sway is incomplete. Motion about the ankle joint was dominant only for lateral movement in the frontal plane with narrow stance widths (< 8 cm). For all other conditions most angular motion occurred between the trunk and leg. 6. The large

  1. Crack opening stretch in a plate of finite width

    NASA Technical Reports Server (NTRS)

    Erdogan, F.; Bakioglu, M.

    1974-01-01

    The problem of a uniaxially stressed plate of finite width containing a centrally located damage zone is considered. It is assumed that the flaw may be represented by a part-through crack perpendicular to the plate surface, the net ligaments in the plane of the crack and through-the-thickness narrow strips ahead of the crack ends are fully yielded, and in the yielded sections the material may carry only a constant normal traction with magnitude equal to the yield strength. The problem is solved by neglecting the bending effects and the crack opening stretches at the center and the ends of the crack are obtained. Some applications of the results are indicated by using the concepts of critical crack opening stretch and constant slope plastic instability.

  2. Free-edge delamination: Laminate width and loading conditions effects

    NASA Technical Reports Server (NTRS)

    Murthy, P. L. N.; Chamis, C. C.

    1987-01-01

    The width and loading conditions effects on free-edge stress fields in composite laminates are investigated using a three-dimensional finite element analysis. This analysis includes a special free-edge region refinement or superelement with progrssive substructuring (mesh refinement) and finite thickness interply layers. The different loading conditions include in-plane and out-of-plane bending, combined axial tension and in-plane shear, twisting, uniform temperature and uniform moisture. Results obtained indicate that: axial tension causes the smallest magnitude of interlaminar free edge stress compared to other loading conditions; free-edge delamination data obtained from laboratory specimens cannot be scaled to structural components; and composite structural components are not likely to delaminate.

  3. Three-Level 48-Pulse STATCOM with Pulse Width Modulation

    NASA Astrophysics Data System (ADS)

    Singh, Bhim; Srinivas, Kadagala Venkata

    2016-03-01

    In this paper, a new control strategy of a three-level 48-pulse static synchronous compensator (STATCOM) is proposed with a constant dc link voltage and pulse width modulation at fundamental frequency switching. The proposed STATCOM is realized using eight units of three-level voltage source converters (VSCs) to form a three-level 48-pulse STATCOM. The conduction angle of each three-level VSC is modulated to control the ac converter output voltage, which controls the reactive power of the STATCOM. A fuzzy logic controller is used to control the STATCOM. The dynamic performance of the STATCOM is studied for the control of the reference reactive power, the reference terminal voltage and under the switching of inductive and capacitive loads.

  4. Crack opening stretch in a plate of finite width

    NASA Technical Reports Server (NTRS)

    Erdogan, F.; Bakioglu, M.

    1975-01-01

    The problem of a uniaxially stressed plate of finite width containing a centrally located damage zone is considered. It is assumed that the flaw may be represented by a part-through crack perpendicular to the plate surface, the net ligaments in the plane of the crack and through-the-thickness narrow strips ahead of the crack ends are fully yielded, and in the yielded sections the material may carry only a constant normal traction with magnitude equal to the yield strength. The problem is solved by neglecting the bending effects and the crack opening stretches at the center and the ends of the crack are obtained. Some applications of the results are indicated by using the concepts of critical crack opening stretch and constant slope plastic instability.

  5. Electron tunnelling through a quantifiable barrier of variable width

    NASA Astrophysics Data System (ADS)

    Wyatt, A. F. G.; Bromberger, H.; Klier, J.; Leiderer, P.; Zech, M.

    2009-02-01

    This is the first study of electron tunnelling through a quantifiable barrier of adjustable width. We find quantitative agreement between the measured and calculated tunnelling probability with no adjustable constants. The tunnel barrier is a thin film of 3He on Cs1 which it wets. We excite photoelectrons which have to tunnel through the barrier to escape. The image potential must be included in calculating the barrier and hence the tunnelling current. This has been a debatable point until now. We confirm that an electron has a potential of 1.0 eV in liquid 3He for short times before a bubble forms. We show that the thickness of the 3He is given by thermodynamics for films of thickness at least down to 3 monolayers.

  6. Free-edge delamination - Laminate width and loading conditions effects

    NASA Technical Reports Server (NTRS)

    Murthy, Pappu L. N.; Chamis, Christos C.

    1989-01-01

    The width and loading conditions effects on free-edge stress fields in composite laminates are investigated using a three-dimensional finite element analysis. This analysis includes a special free-edge region refinement or superelement with progressive substructuring (mesh refinement) and finite thickness interply layers. The different loading conditions include in-plane and out-of-plane bending, combined axial tension and in-plane shear, twisting, uniform temperature and uniform moisture. Results obtained indicate that: axial tension causes the smallest magnitude of interlaminar free edge stress compared to other loading conditions; free-edge delamination data obtained from laboratory specimens cannot be scaled to structural components; and composite structural components are not likely to delaminate.

  7. Josephson effect in mesoscopic graphene strips with finite width

    NASA Astrophysics Data System (ADS)

    Moghaddam, Ali G.; Zareyan, Malek

    2006-12-01

    We study Josephson effect in a ballistic graphene strip of length L smaller than the superconducting coherence length and arbitrary width W . We find that the dependence of the critical supercurrent Ic on W is drastically different for different types of the edges. For smooth and armchair edges at low concentration of the carriers Ic decreases monotonically with decreasing W/L and tends to a constant minimum for a narrow strip W/L≲1 . The minimum supercurrent is zero for smooth edges but has a finite value eΔ0/ℏ for the armchair edges. At higher concentration of the carriers, in addition to this overall monotonic variation, the critical current undergoes a series of peaks with varying W . On the other hand in a strip with zigzag edges the supercurrent is half-integer quantized to (n+1/2)4eΔ0/ℏ , showing a stepwise variation with W .

  8. PCF based high power narrow line width pulsed fiber laser

    NASA Astrophysics Data System (ADS)

    Chen, H.; Yan, P.; Xiao, Q.; Wang, Y.; Gong, M.

    2012-09-01

    Based on semiconductor diode seeded multi-stage cascaded fiber amplifiers, we have obtained 88-W average power of a 1063-nm laser with high repetition rate of up to 1.5 MHz and a constant 2-ns pulse duration. No stimulated Brillouin scattering pulse or optical damage occurred although the maximum pulse peak power has exceeded 112 kW. The output laser exhibits excellent beam quality (M2x = 1.24 and M2y = 1.18), associated with a spectral line width as narrow as 0.065 nm (FWHM). Additionally, we demonstrate high polarization extinction ratio of 18.4 dB and good pulse stabilities superior to 1.6 % (RMS).

  9. Three-body effects in the /sup 7/Li (/ital d/,. cap alpha cap alpha. /ital n/) reaction

    SciTech Connect

    Arena, N.; Cavallaro, S.; Fazio, G.; Giardina, G.; Italiano, A.; Herman, M.; Bruno, M.; Cannata, F.; D'Agostino, M.

    1989-07-01

    Measurements of the differential cross sections for the/sup 7/Li(/ital d/,..cap alpha cap alpha..n) reaction have been performed at deuteron incident energy /ital E/(/ital d/)=6.8 MeV. The kinematical configurations were chosen so as to optimize the population of the /sup 5/He/sup **/ 3/2/sup +/ state with 16.76 MeV excitation energy. The parameters of this resonance are deduced from the experimental data; deviations from the standard values indicate the relevance of three-body effects and/or rescattering. Some phenomenological considerations give a qualitative explanation of the results obtained. In particular, as far as the width is concerned, we observe a broadening with respect to the standard value, which may be related to the presence of a shadow pole.

  10. Amplitude and Width Correlations in COBALT-57 and VANADIUM-49.

    NASA Astrophysics Data System (ADS)

    Ramakrishnan, Prabha K.

    Angular distributions of the inelastically scattered protons and of the deexcitation (gamma)-rays in the ('56)Fe(p,p'(gamma)) reaction were measured for d-wave resonances in the proton energy range 3.10 to 4.01 MeV. The experiment was performed with an overall energy resolution of 350 to 400 eV (FWHM) at the Triangle Universities Nuclear Laboratory KN Van de Graaff accelerator and associated high resolution system. Results were obtained for 141 resonances; 83 resonances were assigned J('(pi)) = 5/2('+), while 58 resonances were assigned J('(pi)) = 3/2('+). Mixing parameters for the inelastic decay amplitudes were uniquely determined for the 5/2('+) resonances. For the 3/2('+) resonances sufficient information is not available from this experiment to extract a unique solution for the mixing parameters. Magnitudes and relative signs of three inelastic decay amplitudes were determined for the 5/2('+) resonances in ('57)Co. The angular distributions for the deexcitation (gamma)-rays were measured in coincidence with the inelastically scattered protons for 30 3/2('+) resonances in ('49)V in the proton energy region 2.2 to 3.1 MeV. The singles measurements from a previous experiment were combined with these coincidence measurements to eliminate the ambiguity in the solutions for the mixing parameters. Amplitude and width measurements were determined for the three decay channels for 30 3/2('+) resonances. Statistical analyses were performed on the set of 83 5/2('+) resonances in ('57)Co and on the set of 30 3/2('+) resonances in ('49)V. In both cases, large amplitude and width correlations are observed. These results are interpreted as evidence for direct reactions between the inelastic channels.

  11. The optimum choice of gate width for neutron coincidence counting

    NASA Astrophysics Data System (ADS)

    Croft, S.; Henzlova, D.; Favalli, A.; Hauck, D. K.; Santi, P. A.

    2014-11-01

    In the measurement field of international nuclear safeguards, passive neutron coincidence counting is used to quantify the spontaneous fission rate of certain special nuclear materials. The shift register autocorrelation analysis method is the most commonly used approach. However, the Feynman-Y technique, which is more commonly applied in reactor noise analysis, provides an alternative means to extract the correlation information from a pulse train. In this work we consider how to select the optimum gate width for each of these two time-correlation analysis techniques. The optimum is considered to be that which gives the lowest fractional precision on the net doublets rate. Our theoretical approach is approximate but is instructional in terms of revealing the key functional dependence. We show that in both cases the same performance figure of merit applies so that common design criteria apply to the neutron detector head. Our prediction is that near optimal results, suitable for most practical applications, can be obtained from both techniques using a common gate width setting. The estimated precision is also comparable in the two cases. The theoretical expressions are tested experimentally using 252Cf spontaneous fission sources measured in two thermal well counters representative of the type in common use by international inspectorates. Fast accidental sampling was the favored method of acquiring the Feynman-Y data. Our experimental study confirmed the basic functional dependences predicted although experimental results when available are preferred. With an appropriate gate setting Feynman-Y analysis provides an alternative to shift register analysis for safeguards applications which is opening up new avenues of data collection and data reduction to explore.

  12. Optimal gate-width setting for passive neutrons multiplicity counting

    SciTech Connect

    Croft, Stephen; Evans, Louise G; Schear, Melissa A

    2010-01-01

    When setting up a passive neutron coincidence counter it is natural to ask what coincidence gate settings should be used to optimize the counting precision. If the gate width is too short then signal is lost and the precision is compromised because in a given period only a few coincidence events will be observed. On the other hand if the gate is too large the signal will be maximized but it will also be compromised by the high level of random pile-up or Accidental coincidence events which must be subtracted. In the case of shift register electronics connected to an assay chamber with an exponential dieaway profile operating in the regime where the Accidentals rate dominates the Reals coincidence rate but where dead-time is not a concern, simple arguments allow one to show that the relative precision on the net Reals rate is minimized when the coincidence gate is set to about 1.2 times the lie dieaway time of the system. In this work we show that making the same assumptions it is easy to show that the relative precision on the Triples rates is also at a minimum when the relative precision of the Doubles (or Reals) is at a minimum. Although the analysis is straightforward to our knowledge such a discussion has not been documented in the literature before. Actual measurement systems do not always behave in the ideal we choose to model them. Fortunately however the variation in the relative precision as a function of gate width is rather flat for traditional safeguards counters and so the performance is somewhat forgiving of the exact choice. The derivation further serves to delineate the important parameters which determine the relative counting precision of the Doubles and Triples rates under the regime considered. To illustrate the similarities and differences we consider the relative standard deviation that might be anticipated for a passive correlation count of an axial section of a spent nuclear fuel assembly under practically achievable conditions.

  13. Variability of Lyman-alpha emission from Jupiter

    NASA Technical Reports Server (NTRS)

    Cochran, W. D.; Barker, E. S.

    1979-01-01

    The Jovian Lyman-alpha emission line was reobserved in 1978 March using the high-resolution spectrometer of the Copernicus satellite. An intensity of 8.3 plus or minus 2.9 kilorayleighs was measured. This value represents a significant increase in intensity over previous (1976) Copernicus observations, but is lower than the recent (1979) values obtained by Voyager 1 and IUE. The increase in intensity has been accompanied by a significant increase in line width giving strong support to the theory that the emission results from resonant scattering of the solar Lyman-alpha line by H atoms in the upper Jovian atmossphere. The strength of Jovian Lyman-alpha emission correlates well with the level of solar activity. The solar extreme ultraviolet radiation varies with the solar cycle. This radiation causes the dissociation of H2 and CH4 into H atoms in the Jovian atmosphere. Therefore, in times of high solar activity, the H column density will increase, causing the observed strong Jovian Lyman-alpha emission.

  14. Variability of Lyman-alpha emission from Jupiter

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The Jovian Lyman-alpha emission line was again observed in 1978 using the high resolution spectrometer on the Copernicus satellite. In intensity of 8.4+3.0 kilo Rayleighs was measured. This value represents a significant increase in intensity over previous (1976) Copernicus observations, but is lower than the recent (1979) values obtained by Voyager I and IUE. The increase in intensity was accompanied by a significant increase in line width, giving strong support to the theory that the emission results from resonant scattering of the solar Ly-alpha line by H atoms in the upper Jovian atmosphere. The strength of Jovian Ly-alpha emission correlates well with the level of solar activity. The solar extreme ultraviolet radiation varies with the solar cycle. This radiation causes the dissociation of H2 and CH4 into H atoms in the Jovian atmosphere. Therefore, in times of high solar activity, the H column density will increase, causing the observed stronger Jovian Ly-alpha emission.

  15. Adaptive step-size algorithm for Fourier beam-propagation method with absorbing boundary layer of auto-determined width

    DOE PAGESBeta

    Learn, R.; Feigenbaum, E.

    2016-05-27

    Two algorithms that enhance the utility of the absorbing boundary layer are presented, mainly in the framework of the Fourier beam-propagation method. One is an automated boundary layer width selector that chooses a near-optimal boundary size based on the initial beam shape. Furthermore, the second algorithm adjusts the propagation step sizes based on the beam shape at the beginning of each step in order to reduce aliasing artifacts.

  16. Alpha Kappa Alpha Sorority's Reading Improvement Program for Minorities.

    ERIC Educational Resources Information Center

    Marable, June Morehead

    This document discusses the founding and establishment of Alpha Kappa Alpha Sorority's reading experience pilot project. The efforts of this project were aligned with those of Right to Read and Reading Is Fundamental (RIF). Because of the response from parents and children, plans are being made to increase present operations within the next…

  17. Distribution of total radiation widths for neutron resonances of Pt isotopes

    NASA Astrophysics Data System (ADS)

    Koehler, P. E.; Bečvář, F.; Krtička, M.

    2015-05-01

    High quality neutron capture and transmission data were measured on isotopically enriched 192,194,195,196Pt and natural Pt samples at ORELA. R-matrix analysis of this data revealed resonance parameters for 159, 413, 423, 258, and 11 neutron resonances for neutron energies below 5.0, 16.0, 7.5, 16.0, and 5.0 keV for 192,194,195,196,198Pt+n, respectively. Earlier analysis of data on reduced neutron widths, Γ0n, showed that the distributions of Γ0n for 192,194Pt deviate significantly from the Porter-Thomas distribution (PTD) predicted by random matrix theory. In this contribution we report on preliminary results of the analysis of distribution of total radiation widths, Γγ, in 192,194,195,196Pt+n reactions. Comparison of experimental data with predictions made within the nuclear statistical model indicates that standard models of Photon Strength Functions (PSFs) and Nuclear Level Density predict Γγ distributions which are too narrow. We found that satisfactory agreement between experimental and simulated distributions can be obtained only by a strong suppression of the PSFs at low γ-ray energies and/or by violation of the usual assumption that primary transitions from neutron resonances follow the PTD. The shape of PSFs needed for reproduction of our Γγ data also nicely reproduces spectra from several (n,γ) experiments on the neighbor nuclide 198Au.

  18. Influence of the transition width on the magnetocaloric effect across the magnetostructural transition of Heusler alloys.

    PubMed

    Cugini, F; Porcari, G; Fabbrici, S; Albertini, F; Solzi, M

    2016-08-13

    We report a complete structural and magneto-thermodynamic characterization of four samples of the Heusler alloy Ni-Co-Mn-Ga-In, characterized by similar compositions, critical temperatures and high inverse magnetocaloric effect across their metamagnetic transformation, but different transition widths. The object of this study is precisely the sharpness of the martensitic transformation, which plays a key role in the effective use of materials and which has its origin in both intrinsic and extrinsic effects. The influence of the transition width on the magnetocaloric properties has been evaluated by exploiting a phenomenological model of the transformation built through geometrical considerations on the entropy versus temperature curves. A clear result is that a large temperature span of the transformation is unfavourable to the magnetocaloric performance of a material, reducing both isothermal entropy change and adiabatic temperature change obtainable in a given magnetic field and increasing the value of the maximum field needed to fully induce the transformation. The model, which is based on standard magnetometric and conventional calorimetric measurements, turns out to be a convenient tool for the determination of the optimum values of transformation temperature span in a trade-off between sheer performance and amplitude of the operating range of a material.This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'. PMID:27402934

  19. Band widths and gaps from the Tran-Blaha functional: Comparison with many-body perturbation theory

    NASA Astrophysics Data System (ADS)

    Waroquiers, David; Lherbier, Aurélien; Miglio, Anna; Stankovski, Martin; Poncé, Samuel; Oliveira, Micael J. T.; Giantomassi, Matteo; Rignanese, Gian-Marco; Gonze, Xavier

    2013-02-01

    For a set of ten crystalline materials (oxides and semiconductors), we compute the electronic band structures using the Tran-Blaha [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.102.226401 102, 226401 (2009)] (TB09) functional. The band widths and gaps are compared with those from the local-density approximation (LDA) functional, many-body perturbation theory (MBPT), and experiments. At the density-functional theory (DFT) level, TB09 leads to band gaps in much better agreement with experiments than LDA. However, we observe that it globally underestimates, often strongly, the valence (and conduction) band widths (more than LDA). MBPT corrections are calculated starting from both LDA and TB09 eigenenergies and wave functions. They lead to a much better agreement with experimental data for band widths. The band gaps obtained starting from TB09 are close to those from quasiparticle self-consistent GW calculations, at a much reduced cost. Finally, we explore the possibility to tune one of the semiempirical parameters of the TB09 functional in order to obtain simultaneously better band gaps and widths. We find that these requirements are conflicting.

  20. How does floodplain width affect floodplain river ecology? A preliminary exploration using simulations

    NASA Astrophysics Data System (ADS)

    Power, Mary E.; Parker, Gary; Dietrich, William E.; Sun, Adrian

    1995-09-01

    Hydraulic food chain models allow us to explore the linkages of river discharge regimes and river-floodplain morphology to the structure and dynamics of modeled food webs. Physical conditions (e.g. depth, width, velocity) that vary with river discharge affect the performance (birth, growth, feeding, movement, or death rates) of organisms or trophic groups. Their performances in turn affect their impacts on food webs and ecosystems in channel and floodplain habitats. Here we explore the impact of floodplain width (modeled as 1 ×, 10× and 40× the channel width) on a food web with two energy sources (detritus and vegetation), invertebrates that consume these, a size structured fish population which consumes invertebrates and in which larger fish cannibalize small fish, and birds which feed on large fish. Hydraulic linkages to trophic dynamics are assumed to be mediated in three ways: birds feed efficiently only in shallow water; plant carrying capacity varies non-linearly with water velocity, and mobile and drifting organisms are diluted and concentrated with spillover of river discharge to the floodplain, and its reconfinement to the channel. Aspects of this model are based on field observations of Junk and Bailey from the Amazon, of Sparks from the Mississippi, and on our observations of the Fly River in Papua New Guinea. The model produced several counter-intuitive results. Biomass of invertebrates and fish increased with floodplain width, but much more rapidly from 1 × to 10 × floodplains than from 10 × to 40 × floodplains. For birds, maximum biomass occurred on the 10× floodplain. Initially high bird biomass on the 40 × floodplain declined to extinction over time, because although favorable fishing conditions (shallow water) were most prolonged on the widest floodplain, this advantage was more than offset by the greater dilution of prey after spillover. Bird predation on large fish sometimes increased their biomass, by reducing cannibalism and thereby

  1. Width change of a planar magma path: implication for the evolution and style of volcanic eruptions

    NASA Astrophysics Data System (ADS)

    Ida, Yoshiaki

    1992-12-01

    The width change of a planar path filled with magma is analyzed, assuming that the process is controlled by laminar flow of an incompressible viscous magma between movable parallel walls of country rock. The analysis shows that the width of a planar path changes at a rate is proportional to the effective opening pressure, which is defined as the pressure of the penetrating magma plus the tensile stress component stretching the fluid interface. When the opening pressure is a positive constant, the fissure widens at an accelerating rate and finally diverges at a critical time constant, which depends on the initial size of the fissure and the viscosity of magma as well as on the opening pressure. In contrast, the fissure gradually narrows under a negative opening pressure. This result is applicable to a variety of magmatic processes. First, the orientation of a volcanic fissure or a dike is such that the tensile stress component is maximized, because a fissure with this orientation becomes wider than those at other orientations, as it has the minimum value of critical time constant. Second, local irregularities in the geometrical and mechanical conditions of the magma sheet lead to significant variations in fissure width in the widening process. This nonuniform increase in width is further exaggerated by mechanical and thermal erosion of the wall rock, which makes the irregular surfaces irrecoverable. In this manner, a planar magma path tends to be split into isolated cylindrical conduits when the magma pressure is reduced and the fissure closes as a whole. Some actual fissure eruptions, such as those at Kilauea and Izu-Oshima, show evolutionary processes consistent with this prediction. Another application of the analysis is to explain how the style of a volcanic eruption is determined by the tectonics. Specifically, extensional tectonics, which gives a positive opening pressure for any magma pressure, allows magma to ascend dispersively along various paths, and

  2. Catalogue of equivalent widths and line intensities for prominences observed during 1964-1965

    NASA Technical Reports Server (NTRS)

    Rakhubovskiy, A. S.

    1973-01-01

    The method of observation and processing of the prominence spectra are described briefly. The equivalent widths, central intensities, half-widths and Doppler halfwidths are presented of the emission lines of the prominences.

  3. [The interaction of human alpha 1-antitrypsin with human plasmin].

    PubMed

    Sakurama, S

    1984-01-01

    The interaction of alpha 1-antitrypsin (alpha 1-AT) with plasmin was investigated, and the molecular weight of the inhibitor was also re-evaluated. The value of molecular weight of alpha 1-AT determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) method showed a difference depending on the presence or absence of the reducing agent, resulting in 72,000 dalton before reduction and 59,000 dalton after reduction. Conclusively, the molecular weight of alpha 1-AT was appropriate to be 59,000 dalton from considering the molecular shape of the protein. The interaction of alpha 1-AT with plasmin was analysed by SDS-PAGE method. Unreduced analysis revealed that two kinds of complexes with different molecular weight (the major of 155,000 dalton and the minor of 140,000 dalton) were formed time dependently, suggesting that the former was a native complex and the latter was a degraded product. Reduced analysis disclosed that the light chain of plasmin involved the complex formation with the inhibitor, and a peptide of 16,000 dalton appeared during the reaction. From these observations, the mechanism of action was summarized as follows. First, alpha 1-AT inhibited all of the plasmin activities by forming a 1: 1 stoichiometric complex with the enzyme, presumably with the active center of the enzyme, whose complex is undissociable in the presence of denaturing or reducing agents or both. Secondly, the native complex broke into a degraded product and a released peptide by limited proteolysis with the free plasmin which existed in the reaction mixture even with an excess of alpha 1-AT due to the reaction of complex formation being time consuming. The clinical significance of alpha 1-AT on fibrinolysis was also subject for discussion. PMID:6232193

  4. Alpha 2-adrenergic receptor turnover in adipose tissue and kidney: irreversible blockade of alpha 2-adrenergic receptors by benextramine

    SciTech Connect

    Taouis, M.; Berlan, M.; Lafontan, M.

    1987-01-01

    The recovery of post- and extrasynaptic alpha 2-adrenergic receptor-binding sites was studied in vivo in male golden hamsters after treatment with an irreversible alpha-adrenoceptor antagonist benextramine, a tetramine disulfide that possesses a high affinity for alpha 2-binding sites. The kidney alpha 2-adrenergic receptor number was measured with (/sup 3/H)yohimbine, whereas (/sup 3/H)clonidine was used for fat cell and brain membrane alpha 2-binding site identification. Benextramine treatment of fat cell, kidney, and brain membranes reduced or completely suppressed, in an irreversible manner, (/sup 3/H) clonidine and (/sup 3/H)yohimbine binding without modifying adenosine (A1-receptor) and beta-adrenergic receptor sites. This irreversible binding was also found 1 and 2 hr after intraperitoneal administration of benextramine to the hamsters. Although it bound irreversibly to peripheral and central alpha 2-adrenergic receptors on isolated membranes, benextramine was unable to cross the blood-brain barrier of the hamster at the concentrations used (10-20 mg/kg). After the irreversible blockade, alpha 2-binding sites reappeared in kidney and adipose tissue following a monoexponential time course. Recovery of binding sites was more rapid in kidney than in adipose tissue; the half-lives of the receptor were 31 and 46 hr, respectively in the tissues. The rates of receptor production were 1.5 and 1.8 fmol/mg of protein/hr in kidney and adipose tissue. Reappearance of alpha 2-binding sites was associated with a rapid recovery of function (antilipolytic potencies of alpha 2-agonists) in fat cells inasmuch as occupancy of 15% of (/sup 3/H)clonidine-binding sites was sufficient to promote 40% inhibition of lipolysis. Benextramine is a useful tool to estimate turnover of alpha 2-adrenergic receptors under normal and pathological situations.

  5. Calculations of {alpha}-decay half-lives for heavy and superheavy nuclei

    SciTech Connect

    Qian Yibin; Ni Dongdong; Ren, Zhongzhou

    2011-04-15

    Systematic calculations on the {alpha}-decay half-lives of heavy and superheavy nuclei are performed within a deformed version of the cluster model, using the modified two-potential approach. The deformed Woods-Saxon potential is employed to calculate the {alpha}-decay width through a deformed barrier. For comparison the calculated {alpha}-decay half-lives in the empirical relations are also presented. The present study is initially restricted to even-even nuclei in the heavy mass region with N>126. Then the study is extended to the recently observed heaviest nuclei, including synthesized superheavy elements and isotopes. The {alpha}-decay half-lives obtained are found to be in good agreement with the experimental data.

  6. Membrane remodeling, an early event in benzo[alpha]pyrene-induced apoptosis

    SciTech Connect

    Tekpli, Xavier; Rissel, Mary; Huc, Laurence; Catheline, Daniel; Sergent, Odile; Rioux, Vincent; Legrand, Philippe; Holme, Jorn A.; Dimanche-Boitrel, Marie-Therese; Lagadic-Gossmann, Dominique

    2010-02-15

    Benzo[alpha]pyrene (B[alpha]P) often serves as a model for mutagenic and carcinogenic polycyclic aromatic hydrocarbons (PAHs). Our previous work suggested a role of membrane fluidity in B[alpha]P-induced apoptotic process. In this study, we report that B[alpha]P modifies the composition of cholesterol-rich microdomains (lipid rafts) in rat liver F258 epithelial cells. The cellular distribution of the ganglioside-GM1 was markedly changed following B[alpha]P exposure. B[alpha]P also modified fatty acid composition and decreased the cholesterol content of cholesterol-rich microdomains. B[alpha]P-induced depletion of cholesterol in lipid rafts was linked to a reduced expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase). Aryl hydrocarbon receptor (AhR) and B[alpha]P-related H{sub 2}O{sub 2} formation were involved in the reduced expression of HMG-CoA reductase and in the remodeling of membrane microdomains. The B[alpha]P-induced membrane remodeling resulted in an intracellular alkalinization observed during the early phase of apoptosis. In conclusion, B[alpha]P altered the composition of plasma membrane microstructures through AhR and H{sub 2}O{sub 2} dependent-regulation of lipid biosynthesis. In F258 cells, the B[alpha]P-induced membrane remodeling was identified as an early apoptotic event leading to an intracellular alkalinization.

  7. Microscopic cluster model of {alpha}+n, {alpha}+p, {alpha}+ {sup 3}He, and {alpha}+{alpha} elastic scattering from a realistic effective nuclear interaction

    SciTech Connect

    Dohet-Eraly, J.; Baye, D.

    2011-07-15

    An effective nucleon-nucleon interaction adapted to cluster-model calculations of collisions is derived from the realistic Argonne potential AV18 with the unitary correlation operator method. The unitary correlation is determined from the {alpha}+{alpha} elastic phase shifts calculated in a cluster approach by the generator coordinate method coupled with the microscopic R-matrix method. With this interaction, the elastic phase shifts for the {alpha}+n, {alpha}+p, and {alpha}+{sup 3}He collisions are calculated within the same model. Without further adjustment, a good agreement with experimental data is obtained with a small model space.

  8. Selective alpha particle decay of 12C+12C resonances to excited 20Ne rotational bands observed in the 12C(12C,α)20Ne reaction

    NASA Astrophysics Data System (ADS)

    Ledoux, R. J.; Ordon¯Ez, C. E.; Bechara, M. J.; Al-Juwair, H. A.; Lavelle, G.; Cosman, E. R.

    1984-09-01

    Excitation functions of the 12C(12C,α)20Ne reaction were measured at θlab=7.5° between Ec.m.=14-40 MeV and angular distributions were measured from Ec.m.=17.8 to 20.6 MeV. Summed yields reveal prominent intermediate structure resonances over the entire range which correlate well to resonances previously observed in elastic data. The resonances show enhanced decays to excited rotational bands in 20Ne with reduced widths comparable to those for the elastic channel and an order of magnitude greater than those for the 20Ne ground state band. A discussion is given of the resonances as shape-isomeric states in a shell model secondary minimum in 24Mg, and of the selective alpha decay as being transitions to states of related configuration in 20Ne.

  9. DFT CONFORMATIONAL STUDIES OF ALPHA-MALTOTRIOSE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent DFT optimization studies on alpha-maltose improved our understanding of the preferred conformations of alpha-maltose and the present study extends these studies to alpha-maltotriose with three alpha-D-glucopyranose residues linked by two alpha-[1-4] bridges, denoted herein as DP-3's. Combina...

  10. Alpha particle emitters in medicine

    SciTech Connect

    Fisher, D.R.

    1989-09-01

    Radiation-induced cancer of bone, liver and lung has been a prominent harmful side-effect of medical applications of alpha emitters. In recent years, however, the potential use of antibodies labeled with alpha emitting radionuclides against cancer has seemed promising because alpha particles are highly effective in cell killing. High dose rates at high LET, effectiveness under hypoxic conditions, and minimal expectancy of repair are additional advantages of alpha emitters over antibodies labeled with beta emitting radionuclides for cancer therapy. Cyclotron-produced astatine-211 ({sup 211}At) and natural bismuth-212 ({sup 212}Bi) have been proposed and are under extensive study in the United States and Europe. Radium-223 ({sup 223}Ra) also has favorable properties as a potential alpha emitting label, including a short-lived daughter chain with four alpha emissions. The radiation dosimetry of internal alpha emitters is complex due to nonuniformly distributed sources, short particle tracks, and high relative specific ionization. The variations in dose at the cellular level may be extreme. Alpha-particle radiation dosimetry, therefore, must involve analysis of statistical energy deposition probabilities for cellular level targets. It must also account fully for nonuniform distributions of sources in tissues, source-target geometries, and particle-track physics. 18 refs., 4 figs.

  11. Prothymosin alpha in human blood.

    PubMed Central

    Panneerselvam, C; Haritos, A A; Caldarella, J; Horecker, B L

    1987-01-01

    The major cross-reacting peptide in human plasma detected with a radioimmunoassay (RIA) for thymosin alpha 1 was identified as prothymosin alpha, based on its elution properties in gel-filtration chromatography and its amino acid composition after purification by HPLC. A small quantity (less than 10%) of the total cross-reacting material was recovered in fractions corresponding to lower molecular weight thymosin alpha 1-like peptides. The total quantity of cross-reacting material detected in human blood, expressed as thymosin alpha 1 equivalents, was 11-14 pmol/ml (approximately 90% was recovered in the leukocyte fraction, approximately 10% was in the plasma fraction, and 1-2% was in the erythrocyte fraction). The peptide present in leukocytes was also identified as prothymosin alpha. After correction for the 5-times lower molar reactivity of prothymosin alpha in the thymosin alpha 1 RIA employed in these experiments, we estimate that the content of prothymosin alpha in human blood is 55-70 pmol/ml (0.6-0.8 microgram/ml). The relatively small quantities recovered in the erythrocyte and plasma fractions may be attributed to contamination of the former by leukocytes or to leakage from leukocytes into the plasma. PMID:3474615

  12. EEG Alpha Power and Intelligence.

    ERIC Educational Resources Information Center

    Doppelmayr, M.; Klimesch, W.; Stadler, W.; Pollhuber, D.; Heine, C.

    2002-01-01

    Tested whether alpha power in different sub-bands is selectively related to intelligence. For 74 Austrian subjects, the EEG was recorded during a resting session and 2 different intelligence tests were performed. Findings show a strong positive correlation between intelligence and alpha power. (SLD)

  13. Limits for the 3[alpha] branching ratio of the decay of the 7. 65 MeV, 0[sub 2][sup +] state in [sup 12]C

    SciTech Connect

    Freer, M.; Wuosmaa, A.H.; Betts, R.R.; Henderson, D.J.; Wilt, P. ); Zurmuehle, R.W.; Balamuth, D.P.; Barrow, S.; Benton, D.; Li, Q.; Liu, Z.; Miao, Y. )

    1994-04-01

    A study of the [sup 12]C([sup 12]C, 3[alpha])[sup 12]C reaction has been performed in order to determine the magnitude of the process by which the 7.65 MeV, 0[sub 2][sup +], state in [sup 12]C breaks up directly into three alpha particles, in contrast to the sequential decay through [sup 8]Be. The strength of this decay channel has important implications for the production rate of [sup 12]C in stellar nucleosynthesis. The present measurement indicates that the contribution of this decay process to the alpha width, [Gamma][sub [alpha

  14. THE FORMATION OF THE H{alpha} LINE IN THE SOLAR CHROMOSPHERE

    SciTech Connect

    Leenaarts, J.; Carlsson, M.; Rouppe van der Voort, L. E-mail: mats.carlsson@astro.uio.no

    2012-04-20

    We use state-of-the-art radiation-MHD simulations and three-dimensional (3D) non-LTE radiative transfer computations to investigate H{alpha} line formation in the solar chromosphere and apply the results of this investigation to develop the potential of H{alpha} as a diagnostic of the chromosphere. We show that one can accurately model H{alpha} line formation assuming statistical equilibrium and complete frequency redistribution provided the computation of the model atmosphere included non-equilibrium ionization of hydrogen and the Ly{alpha} and Ly{beta} line profiles are described by Doppler profiles. We find that 3D radiative transfer is essential in modeling hydrogen lines due to the low photon destruction probability in H{alpha}. The H{alpha} opacity in the upper chromosphere is mainly sensitive to the mass density and only weakly sensitive to the temperature. We find that the H{alpha} line-core intensity is correlated with the average formation height: The larger the average formation height is, the lower the intensity will be. The line-core width is a measure of the gas temperature in the line-forming region. The fibril-like dark structures seen in H{alpha} line-core images computed from our model atmosphere are tracing magnetic field lines. These structures are caused by field-aligned ridges of enhanced chromospheric mass density that raise their average formation height, and therefore make them appear dark against their deeper-formed surroundings. We compare with observations, and find that the simulated line-core widths are very similar to the observed ones, without the need for additional microturbulence.

  15. Diabetes and Alpha Lipoic Acid

    PubMed Central

    Golbidi, Saeid; Badran, Mohammad; Laher, Ismail

    2011-01-01

    Diabetes mellitus is a multi-faceted metabolic disorder where there is increased oxidative stress that contributes to the pathogenesis of this debilitating disease. This has prompted several investigations into the use of antioxidants as a complementary therapeutic approach. Alpha lipoic acid, a naturally occurring dithiol compound which plays an essential role in mitochondrial bioenergetic reactions, has gained considerable attention as an antioxidant for use in managing diabetic complications. Lipoic acid quenches reactive oxygen species, chelates metal ions, and reduces the oxidized forms of other antioxidants such as vitamin C, vitamin E, and glutathione. It also boosts antioxidant defense system through Nrf-2-mediated antioxidant gene expression and by modulation of peroxisome proliferator activated receptors-regulated genes. ALA inhibits nuclear factor kappa B and activates AMPK in skeletal muscles, which in turn have a plethora of metabolic consequences. These diverse actions suggest that lipoic acid acts by multiple mechanisms, many of which have only been uncovered recently. In this review we briefly summarize the known biochemical properties of lipoic acid and then discussed the oxidative mechanisms implicated in diabetic complications and the mechanisms by which lipoic acid may ameliorate these reactions. The findings of some of the clinical trials in which lipoic acid administration has been tested in diabetic patients during the last 10 years are summarized. It appears that the clearest benefit of lipoic acid supplementation is in patients with diabetic neuropathy. PMID:22125537

  16. An overview on 5alpha-reductase inhibitors.

    PubMed

    Aggarwal, Saurabh; Thareja, Suresh; Verma, Abhilasha; Bhardwaj, Tilak Raj; Kumar, Manoj

    2010-02-01

    Benign prostatic hyperplasia (BPH) is the noncancerous proliferation of the prostate gland associated with benign prostatic obstruction and lower urinary tract symptoms (LUTS) such as frequency, hesitancy, urgency, etc. Its prevalence increases with age affecting around 70% by the age of 70 years. High activity of 5alpha-reductase enzyme in humans results in excessive dihydrotestosterone levels in peripheral tissues and hence suppression of androgen action by 5alpha-reductase inhibitors is a logical treatment for BPH as they inhibit the conversion of testosterone to dihydrotestosterone. Finasteride (13) was the first steroidal 5alpha-reductase inhibitor approved by U.S. Food and Drug Administration (USFDA). In human it decreases the prostatic DHT level by 70-90% and reduces the prostatic size. Dutasteride (27) another related analogue has been approved in 2002. Unlike Finasteride, Dutasteride is a competitive inhibitor of both 5alpha-reductase type I and type II isozymes, reduced DHT levels >90% following 1 year of oral administration. A number of classes of non-steroidal inhibitors of 5alpha-reductase have also been synthesized generally by removing one or more rings from the azasteroidal structure or by an early non-steroidal lead (ONO-3805) (261). In this review all categories of inhibitors of 5alpha-reductase have been covered. PMID:19879888

  17. Hepatocyte nuclear factor-3 alpha (HNF-3{alpha}) negatively regulates androgen receptor transactivation in prostate cancer cells

    SciTech Connect

    Lee, Hyun Joo; Hwang, Miok; Chattopadhyay, Soma; Choi, Hueng-Sik; Lee, Keesook

    2008-03-07

    The androgen receptor (AR) is involved in the development and progression of prostate cancers. However, the mechanisms by which this occurs remain incompletely understood. In previous reports, hepatocyte nuclear factor-3{alpha} (HNF-3{alpha}) has been shown to be expressed in the epithelia of the prostate gland, and has been determined to regulate the transcription of prostate-specific genes. In this study, we report that HNF-3{alpha} functions as a novel corepressor of AR in prostatic cells. HNF-3{alpha} represses AR transactivation on target promoters containing the androgen response element (ARE) in a dose-dependent manner. HNF-3{alpha} interacts physically with AR, and negatively regulates AR transactivation via competition with AR coactivators, including GRIP1. Furthermore, HNF-3{alpha} overexpression reduces the androgen-induced expression of prostate-specific antigen (PSA) in LNCaP cells. Taken together, our findings indicate that HNF-3{alpha} is a novel corepressor of AR, and predict its effects on the proliferation of prostate cancer cells.

  18. Improved HBT performance by base width reduction and selective extrinsic base regrowth

    NASA Astrophysics Data System (ADS)

    Hsin, Yue-Ming

    Heterojunction bipolar transistors (HBTs) have many advantages, including high current gain, low base resistance, and high cutoff frequency (fsb{T}). For the further improvement of HBT performance, it is worthwhile to scale down device dimensions (in both vertical and lateral directions). The objective of this dissertation is to improve HBT performance by (1) using very thin base layers (down to 200A) which provide higher current gain and higher cutoff frequency; and (2) regrowing extrinsic base layers which provide lower base resistance and higher fsb{max}. This objective has been implemented by using very thin base width HBTs followed by extrinsic base regrowth to retain the advantages of thin base layers. One of the difficulties in lateral scaling of HBTs is associated with recombination at the edges of the emitter, which leads to reduced current gain in small devices. HBTs with base layer thickness scaled down to 200A were found to have both base surface recombination current and base bulk recombination current significantly lower than in comparable devices with greater base width. Base width reduction also reduces base transit time and thus increases fsb{T}. Undesirable side effects from base width reduction are increased base resistance and difficulty in accessing the thin base layer. It is shown this processing difficulty can be alleviated by using InGaP/GaAs layers to form HBTs instead of AlGaAs/GaAs layers, because of the excellent etching selectivity possible between InGaP and GaAs. Also fabricated InGaP/GaAs HBTs demonstrate significantly lower surface recombination current, since with selective etching solution the InGaP emitter layer can be removed, but etching stops on the thin GaAs base layer, resulting in less exposed base-emitter junction area. But thin base InGaP/GaAs HBTs still suffer from high base resistance. The problems of high base resistance and processing difficulty can be eliminated simultaneously by using external base regrowth to reduce

  19. Coupling Between Microstrip Lines With Finite Width Ground Plane Embedded in Thin Film Circuits

    NASA Technical Reports Server (NTRS)

    Ponchak, George E.; Dalton, Edan; Tentzeris, Manos M.; Papapolymerou, John

    2003-01-01

    Three-dimensional (3D) interconnects built upon multiple layers of polyimide are required for constructing 3D circuits on CMOS (low resistivity) Si wafers, GaAs, and ceramic substrates. Thin film microstrip lines (TFMS) with finite width ground planes embedded in the polyimide are often used. However, the closely spaced TFMS lines a r e susceptible to high levels of coupling, which degrades circuit performance. In this paper, Finite Difference Time Domain (FDTD) analysis and experimental measurements a r e used to show that the ground planes must be connected by via holes to reduce coupling in both the forward and backward directions. Furthermore, it is shown that coupled microstrip lines establish a slotline type mode between the two ground planes and a dielectric waveguide type mode, and that the via holes recommended here eliminate these two modes.

  20. A Novel Transcranial Magnetic Stimulator Inducing Near Rectangular Pulses with Controllable Pulse Width (cTMS)

    PubMed Central

    Jalinous, Reza; Lisanby, Sarah H.

    2013-01-01

    A novel transcranial magnetic stimulation (TMS) device with controllable pulse width (PW) and near rectangular pulse shape (cTMS) is described. The cTMS device uses an insulated gate bipolar transistor (IGBT) with appropriate snubbers to switch coil currents up to 7 kA, enabling PW control from 5 μs to over 100 μs. The near-rectangular induced electric field pulses use 22–34% less energy and generate 67–72% less coil heating compared to matched conventional cosine pulses. CTMS is used to stimulate rhesus monkey motor cortex in vivo with PWs of 20 to 100 μs, demonstrating the expected decrease of threshold pulse amplitude with increasing PW. The technological solutions used in the cTMS prototype can expand functionality, and reduce power consumption and coil heating in TMS, enhancing its research and therapeutic applications. PMID:18232369

  1. Pair decay width of the Hoyle state and its role for stellar carbon production.

    PubMed

    Chernykh, M; Feldmeier, H; Neff, T; von Neumann-Cosel, P; Richter, A

    2010-07-01

    The pair decay width of the first excited 0+ state in 12C (the Hoyle state) is deduced from a novel analysis of the world data on inelastic electron scattering covering a wide momentum transfer range, thereby resolving previous discrepancies. The extracted value Γπ=(62.3±2.0) μeV is independently confirmed by new data at low momentum transfers measured at the S-DALINAC and reduces the uncertainty of the literature values by more than a factor of 3. A precise knowledge of Γπ is mandatory for quantitative studies of some key issues in the modeling of supernovae and of asymptotic giant branch stars, the most likely site of the slow-neutron nucleosynthesis process. PMID:20867703

  2. A transcranial magnetic stimulator inducing near-rectangular pulses with controllable pulse width (cTMS).

    PubMed

    Peterchev, Angel V; Jalinous, Reza; Lisanby, Sarah H

    2008-01-01

    A novel transcranial magnetic stimulation (TMS) device with controllable pulse width (PW) and near-rectangular pulse shape (cTMS) is described. The cTMS device uses an insulated gate bipolar transistor (IGBT) with appropriate snubbers to switch coil currents up to 6 kA, enabling PW control from 5 micros to over 100 micros. The near-rectangular induced electric field pulses use 2%-34% less energy and generate 67%-72% less coil heating compared to matched conventional cosine pulses. CTMS is used to stimulate rhesus monkey motor cortex in vivo with PWs of 20 to 100 micros, demonstrating the expected decrease of threshold pulse amplitude with increasing PW. The technological solutions used in the cTMS prototype can expand functionality, and reduce power consumption and coil heating in TMS, enhancing its research and therapeutic applications. PMID:18232369

  3. Stellar Lyman-alpha emission and the local interstellar medium

    NASA Technical Reports Server (NTRS)

    Landsman, Wayne; Simon, Theodore

    1991-01-01

    The UV spectra now available in the IUE archives have been systematically searched for the presence of Lyman-alpha emission in late-type stars. The results provide the first survey of the behavior of the Ly-alpha emission line across most of the cool half of the H-R diagram. The normalized Ly-alpha emission flux is strongest in the chromospherically active RS CVn stars and in the dMe stars. The range of normalized flux values is much smaller among F-type stars than in stars of later spectral type. A dropoff appears in the flux levels of stars at B-V less than 0.30 mag. The measurements are used to search for evidence of possible high column density clouds in the local ISM. The cloud previously identified toward Alpha Oph may be seen in the reduced flux observed toward Beta Oph.

  4. Modeling of polypeptide chains as C alpha chains, C alpha chains with C beta, and C alpha chains with ellipsoidal lateral chains.

    PubMed

    Fogolari, F; Esposito, G; Viglino, P; Cattarinussi, S

    1996-03-01

    In an effort to reduce the number of degrees of freedom necessary to describe a polypeptide chain we analyze the statistical behavior of polypeptide chains when represented as C alpha chains, C alpha chains with C beta atoms attached, and C alpha chains with rotational ellipsoids as models of side chains. A statistical analysis on a restricted data set of 75 unrelated protein structures is performed. The comparison of the database distributions with those obtained by model calculation on very short polypeptide stretches allows the dissection of local versus nonlocal features of the distributions. The database distribution of the bend angles of polypeptide chains of pseudo bonded C alpha atoms spans a restricted range of values and shows a bimodal structure. On the other hand, the torsion angles of the C alpha chain may assume almost all possible values. The distribution is bimodal, but with a much broader probability distribution than for bend angles. The C alpha - C beta vectors may be taken as representative of the orientation of the lateral chain, as the direction of the bond is close to the direction of the vector joining C alpha to the ad hoc defined center of the "steric mass" of the side chain. Interestingly, both the bend angle defined by C alpha i-C alpha i+1-C beta i+1 and the torsional angle offset of the pseudo-dihedral C alpha i-C alpha i+1-C alpha i+2-C beta i+2 with respect to C alpha i-C alpha i+1-C alpha i+2-C alpha i+3 span a limited range of values. The latter results show that it is possible to give a more realistic representation of polypeptide chains without introducing additional degrees of freedom, i.e., by just adding to the C alpha chain a C beta with given side-chain properties. However, a more realistic description of side chains may be attained by modeling side chains as rotational ellipsoids that have roughly the same orientation and steric hindrance. To this end, we define the steric mass of an atom as proportional to its van der

  5. Estimating the safety effects of lane widths on urban streets in Nebraska using the propensity scores-potential outcomes framework.

    PubMed

    Wood, Jonathan S; Gooch, Jeffrey P; Donnell, Eric T

    2015-09-01

    A sufficient understanding of the safety impact of lane widths in urban areas is necessary to produce geometric designs that optimize safety performance for all users. The overarching trend found in the research literature is that as lane widths narrow, crash frequency increases. However, this trend is inconsistent and is the result of multiple cross-sectional studies that have issues related to lack of control for potential confounding variables, unobserved heterogeneity or omitted variable bias, or endogeneity among independent variables, among others. Using ten years of mid-block crash data on urban arterials and collectors from four cities in Nebraska, crash modification factors (CMFs) were estimated for various lane widths and crash types. These CMFs were developed using the propensity scores-potential outcomes methodology. This method reduces many of the issues associated with cross-sectional regression models when estimating the safety effects of infrastructure-related design features. Generalized boosting, a non-parametric modeling technique, was used to estimate the propensity scores. Matching was performed using both Nearest Neighbor and Mahalanobis matching techniques. CMF estimation was done using mixed-effects negative binomial or Poisson regression with the matched data. Lane widths included in the analysis included 9ft, 10ft, 11ft, and 12ft. Some of the estimated CMFs were point estimates while others were functions of traffic volume (i.e., the CMF changed depending on the traffic volume). Roadways with 10ft travel lanes were found to experience the highest crash frequency relative to other lane widths. Meanwhile, roads with 9ft travel lanes were found to experience the lowest relative crash frequency. While this may be due to increased driver caution when traveling on narrow lanes, it is possible that unobserved factors influenced this result. CMFs for target crash types (sideswipe same-direction and sideswipe opposite-direction) were consistent

  6. Tidal stress in Enceladus' ice shell: dependence on the internal ocean width

    NASA Astrophysics Data System (ADS)

    Behounkova, M.; Tobie, G.; Choblet, G.; Cadek, O.

    2013-12-01

    The eruptions of water vapor and ice particles on Enceladus' south pole together with huge heat production suggest the presence of a strong source of energy within Enceladus' interior. The abnormal endogenic power is most likely the consequence of strong tidal dissipation along the ridges and within the ice shell. Here, we study tidal stress associated to tidal flexing in Enceladus' ice shell for simulations described in Behounkova et al. (2013). In these simulations, we have investigated the conditions for the initiation of convection by systematically varying the orbital parameters (eccentricity), ice grain size and width of an internal ocean (D). For the current eccentricity and global ocean (D=360deg), our results show maximum tidal stress is approximately equal to 0.1MPa. For regional oceans of 120deg and 180deg, the maximum tidal stress is reduced by a factor of ~2.2 and ~1.3, respectively. Maximum tidal stresses differ less than 5% for internal oceans covering more than the southern hemisphere (D>180deg). Moreover, tidal stress patterns vary significantly with the ocean width. Whereas the tidal stresses above the rock interface are high even for areas without internal ocean, a considerable stress decrease is observed toward the surface above areas with no internal ocean. This effect is especially pronounced for cases with small internal ocean (D=<120 deg). The maximum tidal stress scales with eccentricity as expected and the tidal stress changes during onset of convection are rather low. Additionally, we will discuss the effect of rheological model (Maxwell vs. Andrade) on the tidal stress pattern and the heating distribution, as well as the possible effect of reduced viscosity in the active south polar terrain.

  7. Genetics Home Reference: alpha-mannosidosis

    MedlinePlus

    ... Me Understand Genetics Home Health Conditions alpha-mannosidosis alpha-mannosidosis Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Alpha-mannosidosis is a rare inherited disorder that causes ...

  8. Evaluation of partial widths and branching ratios from resonance wave functions

    SciTech Connect

    Goldzak, Tamar; Gilary, Ido; Moiseyev, Nimrod

    2010-11-15

    A quantum system in a given resonance state has different open channels for decay. Partial widths are the decay rates of the resonance (metastable) state into the different open channels. Here we present a rigorous derivation of the partial widths from the solution of a time-dependent Schroedinger equation with outgoing boundary conditions. We show that the sum of the partial widths obtained from the resonance wave function is equal to the total width. The difference with respect to previous studies on partial widths and branching ratios is discussed.

  9. Measurement of effective sheath width around cutoff probe in low-pressure plasmas

    SciTech Connect

    Kim, D. W.; Oh, W. Y.; You, S. J. Kim, J. H.; Chang, H. Y.

    2014-05-15

    Previous studies indicated that the measurement results of microwave probes can be improved by applying the adequate sheath width to their measurement models, and consequently the sheath width around the microwave probe tips has become very important information for microwave probe diagnostics. In this paper, we propose a method for measuring the argon plasma sheath width around the cutoff probe tips by applying the circuit model to the cutoff probe phase spectrum. The measured sheath width of the cutoff probe was found to be in good agreement with the floated sheath width calculated from the Child-Langmuir sheath law. The physical reasons for a discrepancy between the two measurements are also discussed.

  10. Measurement of effective sheath width around cutoff probe in low-pressure plasmas

    NASA Astrophysics Data System (ADS)

    Kim, D. W.; You, S. J.; Kim, J. H.; Chang, H. Y.; Oh, W. Y.

    2014-05-01

    Previous studies indicated that the measurement results of microwave probes can be improved by applying the adequate sheath width to their measurement models, and consequently the sheath width around the microwave probe tips has become very important information for microwave probe diagnostics. In this paper, we propose a method for measuring the argon plasma sheath width around the cutoff probe tips by applying the circuit model to the cutoff probe phase spectrum. The measured sheath width of the cutoff probe was found to be in good agreement with the floated sheath width calculated from the Child-Langmuir sheath law. The physical reasons for a discrepancy between the two measurements are also discussed.

  11. Red blood cell distribution width and cardiovascular diseases

    PubMed Central

    Danese, Elisa; Lippi, Giuseppe

    2015-01-01

    Background The red blood cell distribution width (RDW) is a rather simple measure of red blood cell (RBC) size heterogeneity (i.e., anisocytosis), which is easily calculated by dividing the standard deviation (SD) of erythrocyte volumes for the mean corpuscular volume (MCV). Emerging evidence suggests that, besides RBC abnormalities, many human disorders may be frequently associated with a high degree of anisocytosis. Methods In this narrative review, we analyzed the current scientific literature about the putative role and the potential epidemiologic association between RDW and cardiovascular diseases. The findings of the most representative epidemiological studies were summarized and discussed. Results Overall, considerable and convincing evidence has been brought that an increased RDW value is associated with acute coronary syndrome (ACS) [including acute myocardial infarction (AMI)], ischemic cerebrovascular disease (including stroke), peripheral artery disease (PAD), as well as with atrial fibrillation (AF), heart failure (HF) and hypertension. Higher anisocytosis also significantly and independently predicts adverse outcomes in patients with these conditions. Conclusions Although the role of anisocytosis in the pathogenesis of cardiovascular diseases remains uncertain, the considerable evidence available so far suggests that the clinical use of RDW may be broadened beyond the conventional boundaries of erythrocyte disorders, in particular for assisting the diagnosis and prognostication of patients with ACS, ischemic cerebrovascular disease, PAD, HF and AF. PMID:26623117

  12. Ratio of Spleen Diameter to Red Blood Cell Distribution Width

    PubMed Central

    Balaban, Daniel Vasile; Popp, Alina; Lungu, Andrei Marian; Costache, Raluca Simona; Anca, Ioana Alina; Jinga, Mariana

    2015-01-01

    Abstract Celiac disease (CD) is currently considerably underdiagnosed, setting the need for developing tools to select patients with probability of CD, who warrant further testing. Red blood cell distribution width (RDW) has been shown in previous studies to be a sensitive predictor for CD, but it lacks specificity. Splenic hypotrophy is also noted frequently in celiac patients. Our aim was to evaluate if spleen diameter to RDW ratio can be used as an indicator for CD. We evaluated 15 newly diagnosed CD patients, 52 patients with inflammatory bowel disease, and 35 patients with irritable bowel syndrome (IBS). We evaluated the differences in spleen diameter, RDW, and their ratio among the four groups. Two-thirds of the CD patients had elevated RDW, compared to 9% in the IBS group. A small spleen was seen in 80% of the celiacs, compared to 21.9% in the ulcerative colitis group, 10% in the Crohn disease group, and 9% in the IBS group. A spleen diameter to RDW ratio under 6 had a sensitivity of 73.3% and specificity of 88.5% in predicting CD, with an AUROC of 0.737. Spleen diameter to RDW ratio is a simple, widely available score, which can be used to select adult patients with probability of CD. PMID:25881851

  13. Programming microbes using pulse width modulation of optical signals.

    PubMed

    Davidson, Eric A; Basu, Amar S; Bayer, Travis S

    2013-11-15

    Cells transmit and receive information via signalling pathways. A number of studies have revealed that information is encoded in the temporal dynamics of these pathways and has highlighted how pathway architecture can influence the propagation of signals in time and space. The functional properties of pathway architecture can also be exploited by synthetic biologists to enable precise control of cellular physiology. Here, we characterised the response of a bacterial light-responsive, two-component system to oscillating signals of varying frequencies. We found that the system acted as a low-pass filter, able to respond to low-frequency oscillations and unable to respond to high-frequency oscillations. We then demonstrate that the low-pass filtering behavior can be exploited to enable precise control of gene expression using a strategy termed pulse width modulation (PWM). PWM is a common strategy used in electronics for information encoding that converts a series of digital input signals to an analog response. We further show how the PWM strategy extends the utility of bacterial optogenetic control, allowing the fine-tuning of expression levels, programming of temporal dynamics, and control of microbial physiology via manipulation of a metabolic enzyme. PMID:23928560

  14. Drift effects on the tokamak power scrape-off width

    NASA Astrophysics Data System (ADS)

    Meier, E. T.; Goldston, R. J.; Kaveeva, E. G.; Mordijck, S.; Rozhansky, V. A.; Senichenkov, I. Yu.; Voskoboynikov, S. P.

    2015-11-01

    Recent experimental analysis suggests that the scrape-off layer (SOL) heat flux width (λq) for ITER will be near 1 mm, sharply narrowing the planned operating window. In this work, motivated by the heuristic drift (HD) model, which predicts the observed inverse plasma current scaling, SOLPS-ITER is used to explore drift effects on λq. Modeling focuses on an H-mode DIII-D discharge. In initial results, target recycling is set to 90%, resulting in sheath-limited SOL conditions. SOL particle diffusivity (DSOL) is varied from 0.1 to 1 m2/s. When drifts are included, λq is insensitive to DSOL, consistent with the HD model, with λq near 3 mm; in no-drift cases, λq varies from 2 to 5 mm. Drift effects depress near-separatrix potential, generating a channel of strong electron heat convection that is insensitive to DSOL. Sensitivities to thermal diffusivities, plasma current, toroidal magnetic field, and device size are also assessed. These initial results will be discussed in detail, and progress toward modeling experimentally relevant high-recycling conditions will be reported. Supported by U.S. DOE Contract DE-SC0010434.

  15. Exotic vector charmonium and its leptonic decay width

    NASA Astrophysics Data System (ADS)

    Chen, Ying; Chiu, Wei-Feng; Gong, Ming; Gui, Long-Cheng; Liu, Zhao-Feng

    2016-08-01

    We propose a novel type of interpolating field operator, which manifests the hybrid-like configuration that the charm quark-antiquark pair recoils against gluonic degrees of freedom. A heavy vector charmonium-like state with a mass of 4.33(2),GeV is disentangled from the conventional charmonium states in the quenched approximation. This state has affinity for the hybrid-like operators but couples less to the relevant quark bilinear operator. We also try to extract its leptonic decay constant and give a tentative upper limit that it is less than one tenth of that of J/ψ, which corresponds to a leptonic decay width about dozens of eV. The connection of this state with X(4260) is also discussed. The numerical calculations were carried out on Tianhe-1A at the National Supercomputer Center (NSCC) in Tianjin and the GPU cluster at Hunan Normal University. This work is supported in part by the National Science Foundation of China (NSFC) (11575196, 11575197, 11335001, 11405053), Y.C. and Z.L. also acknowledge the support of NSFC (11261130311) (CRC 110 by DFG and NSFC)

  16. Alpha Rhythms in Audition: Cognitive and Clinical Perspectives

    PubMed Central

    Weisz, Nathan; Hartmann, Thomas; Müller, Nadia; Lorenz, Isabel; Obleser, Jonas

    2011-01-01

    Like the visual and the sensorimotor systems, the auditory system exhibits pronounced alpha-like resting oscillatory activity. Due to the relatively small spatial extent of auditory cortical areas, this rhythmic activity is less obvious and frequently masked by non-auditory alpha-generators when recording non-invasively using magnetoencephalography (MEG) or electroencephalography (EEG). Following stimulation with sounds, marked desynchronizations can be observed between 6 and 12 Hz, which can be localized to the auditory cortex. However knowledge about the functional relevance of the auditory alpha rhythm has remained scarce so far. Results from the visual and sensorimotor system have fuelled the hypothesis of alpha activity reflecting a state of functional inhibition. The current article pursues several intentions: (1) Firstly we review and present own evidence (MEG, EEG, sEEG) for the existence of an auditory alpha-like rhythm independent of visual or motor generators, something that is occasionally met with skepticism. (2) In a second part we will discuss tinnitus and how this audiological symptom may relate to reduced background alpha. The clinical part will give an introduction into a method which aims to modulate neurophysiological activity hypothesized to underlie this distressing disorder. Using neurofeedback, one is able to directly target relevant oscillatory activity. Preliminary data point to a high potential of this approach for treating tinnitus. (3) Finally, in a cognitive neuroscientific part we will show that auditory alpha is modulated by anticipation/expectations with and without auditory stimulation. We will also introduce ideas and initial evidence that alpha oscillations are involved in the most complex capability of the auditory system, namely speech perception. The evidence presented in this article corroborates findings from other modalities, indicating that alpha-like activity functionally has an universal inhibitory role across sensory

  17. Measurement of effective sheath width around the cutoff probe based on electromagnetic simulation

    NASA Astrophysics Data System (ADS)

    Kim, D. W.; You, S. J.; Kim, J. H.; Chang, H. Y.; Yoon, J.-S.; Oh, W. Y.

    2016-05-01

    We inferred the effective sheath width using the cutoff probe and incorporating a full-wave three-dimensional electromagnetic (EM) simulation. The EM simulation reproduced the experimentally obtained plasma-sheath resonance (PSR) on the microwave transmission (S21) spectrum well. The PSR frequency has a one-to-one correspondence with the width of the vacuum layer assumed to be the effective sheath in the EM simulation model. The sheath width was estimated by matching the S21 spectra of the experiment and the EM simulation for different widths of the sheath. We found that the inferred sheath widths quantitatively and qualitatively agree with the sheath width measured by incorporating an equivalent circuit model. These results demonstrate the excellent potential of the cutoff probe for inferring the effective sheath width from its experimental spectrum data.

  18. Numerical prediction and performance experiment in a deep-well centrifugal pump with different impeller outlet width

    NASA Astrophysics Data System (ADS)

    Shi, Weidong; Zhou, Ling; Lu, Weigang; Pei, Bing; Lang, Tao

    2013-01-01

    The existing research of the deep-well centrifugal pump mainly focuses on reduce the manufacturing cost and improve the pump performance, and how to combine above two aspects together is the most difficult and important topic. In this study, the performances of the deep-well centrifugal pump with four different impeller outlet widths are studied by the numerical, theoretical and experimental methods in this paper. Two stages deep-well centrifugal pump equipped with different impellers are simulated employing the commercial CFD software to solve the Navier-Stokes equations for three-dimensional incompressible steady flow. The sensitivity analyses of the grid size and turbulence model have been performed to improve numerical accuracy. The flow field distributions are acquired and compared under the design operating conditions, including the static pressure, turbulence kinetic energy and velocity. The prototype is manufactured and tested to certify the numerical predicted performance. The numerical results of pump performance are higher than the test results, but their change trends have an acceptable agreement with each other. The performance results indicted that the oversize impeller outlet width leads to poor pump performances and increasing shaft power. Changing the performance of deep-well centrifugal pump by alter impeller outlet width is practicable and convenient, which is worth popularizing in the engineering application. The proposed research enhances the theoretical basis of pump design to improve the performance and reduce the manufacturing cost of deep-well centrifugal pump.

  19. Voigt equivalent widths and spectral-bin single-line transmittances: Exact expansions and the MODTRAN®5 implementation

    NASA Astrophysics Data System (ADS)

    Berk, Alexander

    2013-03-01

    Exact expansions for Voigt line-shape total, line-tail and spectral bin equivalent widths and for Voigt finite spectral bin single-line transmittances have been derived in terms of optical depth dependent exponentially-scaled modified Bessel functions of integer order and optical depth independent Fourier integral coefficients. The series are convergent for the full range of Voigt line-shapes, from pure Doppler to pure Lorentzian. In the Lorentz limit, the expansion reduces to the Ladenburg and Reiche function for the total equivalent width. Analytic expressions are derived for the first 8 Fourier coefficients for pure Lorentzian lines, for pure Doppler lines and for Voigt lines with at most moderate Doppler dependence. A strong-line limit sum rule on the Fourier coefficients is enforced to define an additional Fourier coefficient and to optimize convergence of the truncated expansion. The moderate Doppler dependence scenario is applicable to and has been implemented in the MODTRAN5 atmospheric band model radiative transfer software. Finite-bin transmittances computed with the truncated expansions reduce transmittance residuals compared to the former Rodgers-Williams equivalent width based approach by ∼2 orders of magnitude.

  20. Integrins alpha(6A)beta 1 and alpha(6B)beta 1 promote different stages of chondrogenic cell differentiation.

    PubMed

    Segat, Daniela; Comai, Riccardo; Di Marco, Eddi; Strangio, Antonella; Cancedda, Ranieri; Franzi, Adriano T; Tacchetti, Carlo

    2002-08-30

    The differentiation of chondrocytes and of several other cell types is associated with a switch from the alpha(6B) to the alpha(6A) isoform of the laminin alpha(6)beta(1) integrin receptor. To define whether this event plays a functional role in cell differentiation, we used an in vitro model system that allows chick chondrogenic cells to remain undifferentiated when cultured in monolayer and to differentiate into chondrocytes when grown in suspension culture. We report that: (i) upon over-expression of the human alpha(6B), adherent chondrogenic cells differentiate to stage I chondrocytes (i.e. increased type II collagen, reduced type I collagen, fibronectin, alpha(5)beta(1) and growth rate, loss of fibroblast morphology); (ii) the expression of type II collagen requires the activation of p38 MAP kinase; (iii) the over-expression of alpha(6A) induces an incomplete differentiation to stage I chondrocytes, whereas no differentiation was observed in alpha(5) and mock-transfected control cells; (iv) a prevalence of the alpha(6A) subunit is necessary to stabilize the differentiated phenotype when cells are transferred to suspension culture. Altogether, these results indicate a functional role for the alpha(6B) to alpha(6A) switch in chondrocyte differentiation; the former promotes chondrocyte differentiation, and the latter is necessary in stabilizing the differentiated phenotype. PMID:12077132

  1. H-alpha Imaging Survey of Low-Redshift Cluster Dwarf Galaxies

    NASA Astrophysics Data System (ADS)

    Barkhouse, Wayne; Kalawila, Sandanuwan; Rude, Cody; Sultanova, Madina; Archer, Haylee Nichole; Foote, Gregory

    2016-01-01

    We describe our on-going H-alpha imaging survey to measure the star formation activity of dwarf galaxies selected from a sample of low-redshift (0.02 < z< 0.15) galaxy clusters using the KPNO 4-meter telescope+Mosaic camera. H-alpha observations are obtained using the narrow-band BATC filters centered on the redshifted H-alpha emission line. The continuum-subtracted H-alpha images allow us to constrain star formation rates via the correlation between star formation and H-alpha luminosity and equivalent width. The impact of the cluster environment can be quantified using radial-dependent measures of the star formation rate within individual clusters, and by comparing clusters within our sample on a cluster-to-cluster basis. Comparison of our H-alpha measurements to CFHT u-band imaging data of our cluster sample, permits us to explore the correlation between the UV continuum and H-alpha emission of the dwarf galaxy population. The goal of our survey is to further understand the mechanism that is responsible for the enhancement/quenching of star formation as dwarf galaxies fall into the galaxy cluster environment.

  2. Alpha1-antitrypsin suppresses TNF-alpha and MMP-12 production by cigarette smoke-stimulated macrophages.

    PubMed

    Churg, Andrew; Wang, Xiaoshan; Wang, Rong D; Meixner, Scott C; Pryzdial, Edward L G; Wright, Joanne L

    2007-08-01

    We have previously observed that mice exposed to cigarette smoke and treated with exogenous alpha(1)-antitrypsin (A1AT) were protected against the development of emphysema and against smoke-induced increases in serum TNF-alpha. To investigate possible mechanisms behind this latter observation, we cultured alveolar macrophages lavaged from C57 mice. Smoke-conditioned medium caused alveolar macrophages to increase secretion of macrophage metalloelastase (MMP-12) and TNF-alpha, and this effect was suppressed in a dose-response fashion by addition of A1AT. Macrophages from animals exposed to smoke in vivo and then lavaged also failed to increase MMP-12 and TNF-alpha secretion when the animals were pretreated with A1AT. Because proteinase activated receptor-1 (PAR-1) is known to control MMP-12 release, macrophages were treated with the G protein-coupled receptor inhibitor, pertussis toxin; this suppressed both TNF-alpha and MMP-12 release, while a PAR-1 agonist (TRAP) increased TNF-alpha and MMP-12 release. Smoke-conditioned medium caused increased release of the prothrombin activator, tissue factor, from macrophages. Hirudin, a thrombin inhibitor, and aprotinin, an inhibitor of plasmin, reduced smoke-mediated TNF-alpha and MMP-12 release, and A1AT inhibited both plasmin and thrombin activity in a cell-free functional assay. These findings extend our previous suggestion that TNF-alpha production by alveolar macrophages is related to MMP-12 secretion. They also suggest that A1AT can inhibit thrombin and plasmin in blood constituents that leak into the lung after smoke exposure, thereby preventing PAR-1 activation and MMP-12/TNF-alpha release, and decreasing smoke-mediated inflammatory cell influx. PMID:17395890

  3. Integrin {alpha}6 cleavage: A novel modification to modulate cell migration

    SciTech Connect

    Pawar, Sangita C.; Demetriou, Manolis C.; Nagle, Raymond B.; Bowden, G. Tim; Cress, Anne E. . E-mail: acress@azcc.arizona.edu

    2007-04-01

    Integrins play a major role in cell adhesion and migration. Previous work reported that a cleaved form of integrin {alpha}6 ({alpha}6p) was detected in invasive human prostate cancer tissue, absent in normal prostate tissue and was produced by urokinase-type Plasminogen Activator (uPA) in a plasmin-independent manner. Using site-directed mutagenesis we identified amino acid residues R594 and R595, located in the 'stalk' region of integrin {alpha}6, as essential for cleavage. The cleavage site is located on the extracellular region of the protein between the {beta}-barrel domain and the thigh domain. Prostate cancer cells (PC3N) were stably transfected to overexpress the cleavable, wild-type (PC3N-{alpha}6-WT) or the non-cleavable form of integrin {alpha}6 (PC3N-{alpha}6-RR). The number of cells invading laminin 111- and laminin 332-coated filters by PC3N-{alpha}6-WT cells increased by threefold as compared to PC3N-{alpha}6-RR cells. Plasminogen activator inhibitor-1 (PAI-1) reduced the invasion of PC3N-{alpha}6-WT cells by approximately 42% through laminin 332-coated filters and plasmin inhibitor aprotinin had no significant effect. Linear cell migration increased production of integrin {alpha}6p in the PC3N-{alpha}6-WT cells and not in the PC3N-{alpha}6-RR cells and 32% of the PC3N-{alpha}6-WT cells migrated on laminin 111 in the linear migration assay as compared to the 5% PC3N-{alpha}6-RR cells. These data taken together suggest that the uPA-mediated cell surface cleavage of the {alpha}6 integrin extracellular domain is involved in tumor cell invasion and migration on laminin.

  4. Alpha-particle spectrometer experiment

    NASA Technical Reports Server (NTRS)

    Gorenstein, P.; Bjorkholm, P.

    1972-01-01

    Mapping the radon emanation of the moon was studied to find potential areas of high activity by detection of radon isotopes and their daughter products. It was felt that based on observation of regions overflown by Apollo spacecraft and within the field of view of the alpha-particle spectrometer, a radon map could be constructed, identifying and locating lunar areas of outgassing. The basic theory of radon migration from natural concentrations of uranium and thorium is discussed in terms of radon decay and the production of alpha particles. The preliminary analysis of the results indicates no significant alpha emission.

  5. Alpha Oscillatory Dynamics Index Temporal Expectation Benefits in Working Memory.

    PubMed

    Wilsch, Anna; Henry, Molly J; Herrmann, Björn; Maess, Burkhard; Obleser, Jonas

    2015-07-01

    Enhanced alpha power compared with a baseline can reflect states of increased cognitive load, for example, when listening to speech in noise. Can knowledge about "when" to listen (temporal expectations) potentially counteract cognitive load and concomitantly reduce alpha? The current magnetoencephalography (MEG) experiment induced cognitive load using an auditory delayed-matching-to-sample task with 2 syllables S1 and S2 presented in speech-shaped noise. Temporal expectation about the occurrence of S1 was manipulated in 3 different cue conditions: "Neutral" (uninformative about foreperiod), "early-cued" (short foreperiod), and "late-cued" (long foreperiod). Alpha power throughout the trial was highest when the cue was uninformative about the onset time of S1 (neutral) and lowest for the late-cued condition. This alpha-reducing effect of late compared with neutral cues was most evident during memory retention in noise and originated primarily in the right insula. Moreover, individual alpha effects during retention accounted best for observed individual performance differences between late-cued and neutral conditions, indicating a tradeoff between allocation of neural resources and the benefits drawn from temporal cues. Overall, the results indicate that temporal expectations can facilitate the encoding of speech in noise, and concomitantly reduce neural markers of cognitive load. PMID:24488943

  6. Variability of Lyman-alpha and the ultraviolet continuum of 3C 446

    NASA Technical Reports Server (NTRS)

    Bregman, J. N.; Glassgold, A. E.; Huggins, P. J.; Kinney, A. L.

    1986-01-01

    IUE observations have been conducted over the 1230-3175 A range for the violently variable quasar 3C 446, beginning in June 1980, at intervals of 1.2, 2.2, 0.5, and 0.4 yr. Strong absorption of the continuum was found below 1830 A, probably corresponding to a Lyman edge at z of 1.00 + or - 0.01. The absence of Mg II 2798 A absorption implies that the column density is in the lower end of the range, unless the gas is metal-poor. The Lyman-alpha emission line was detected in five spectra; relative to the number of ionizing protons, the line strengths are the same as in normal quasars, and line equivalent widths are small due to the continuum's rise redward of 912 A, which is much steeper than in normal quasars. The Lyman-alpha line and the nearby continuum vary so as to maintain constant equivalent width.

  7. Influence of sound source width on human sound localization.

    PubMed

    Greene, Nathaniel T; Paige, Gary D

    2012-01-01

    Free-field sound localization experiments generally assume that a loudspeaker can be approximated by a point-source; however, a large loudspeaker may extend beyond the width that two sources can be discriminated. Humans can accurately discriminate sound source locations within a few degrees, thus one might expect localization precision to decrease as a function of sound source diameter, much as precision is lower for localizing the center of a wide, blurry light source. In order to test the degree to which humans differentially localize small and large sound sources, auditory targets were presented using a single 25.4 cm by 10.2 cm elliptical loudspeaker with the primary axis oriented both horizontally and vertically in different sessions. Subjects were seated with their heads fixed by a bite bar in a darkened, echo-attenuating room facing a cylindrical, acoustically transparent screen at a distance of 2 meters. Auditory targets consisted of repeating bursts (5 Hz) of low frequency band-pass noise (0.2 - 1 kHz, 75 dB SPL). Subjects were instructed to quickly and accurately guide a laser pointer mounted on a cylindrical joystick towards targets, presented randomly within a field ± 40° in azimuth by ± 10° in elevation, with oversampled points located every ten degrees along the primary meridians. Localization accuracy and precision (mean and standard deviation of localization error at oversampled locations) were not significantly different between speaker orientations, and were comparable to baseline measurements recorded using a 7.6 cm circular speaker. We conclude that low frequency sound localization performance is not dependent upon the size of the sound source as predicted theoretically, and is well approximated by a point source. PMID:23367407

  8. Pulse Width Modulation Applied to Olfactory Stimulation for Intensity Tuning.

    PubMed

    Andrieu, Patrice; Billot, Pierre-Édouard; Millot, Jean-Louis; Gharbi, Tijani

    2015-01-01

    For most olfactometers described in the literature, adjusting olfactory stimulation intensity involves modifying the dilution of the odorant in a neutral solution (water, mineral, oil, etc.), the dilution of the odorant air in neutral airflow, or the surface of the odorant in contact with airflow. But, for most of these above-mentioned devices, manual intervention is necessary for adjusting concentration. We present in this article a method of controlling odorant concentration via a computer which can be implemented on even the most dynamic olfactometers. We used Pulse Width Modulation (PWM), a technique commonly used in electronic or electrical engineering, and we have applied it to odor delivery. PWM, when applied to odor delivery, comprises an alternative presentation of odorant air and clean air at a high frequency. The cycle period (odor presentation and rest) is 200 ms. In order to modify odorant concentration, the ratio between the odorant period and clean air presentation during a cycle is modified. This ratio is named duty cycle. Gas chromatography measurements show that this method offers a range of mixing factors from 33% to 100% (continuous presentation of odor). Proof of principle is provided via a psychophysical experiment. Three odors (isoamyl acetate, butanol and pyridine) were presented to twenty subjects. Each odor was delivered three times with five values of duty cycles. After each stimulation, the subjects were asked to estimate the intensity of the stimulus on a 10 point scale, ranging from 0 (undetectable) to 9 (very strong). Results show a main effect of the duty cycles on the intensity ratings for all tested odors. PMID:26710120

  9. Pulse Width Modulation Applied to Olfactory Stimulation for Intensity Tuning

    PubMed Central

    Millot, Jean-Louis; Gharbi, Tijani

    2015-01-01

    For most olfactometers described in the literature, adjusting olfactory stimulation intensity involves modifying the dilution of the odorant in a neutral solution (water, mineral, oil, etc.), the dilution of the odorant air in neutral airflow, or the surface of the odorant in contact with airflow. But, for most of these above-mentioned devices, manual intervention is necessary for adjusting concentration. We present in this article a method of controlling odorant concentration via a computer which can be implemented on even the most dynamic olfactometers. We used Pulse Width Modulation (PWM), a technique commonly used in electronic or electrical engineering, and we have applied it to odor delivery. PWM, when applied to odor delivery, comprises an alternative presentation of odorant air and clean air at a high frequency. The cycle period (odor presentation and rest) is 200 ms. In order to modify odorant concentration, the ratio between the odorant period and clean air presentation during a cycle is modified. This ratio is named duty cycle. Gas chromatography measurements show that this method offers a range of mixing factors from 33% to 100% (continuous presentation of odor). Proof of principle is provided via a psychophysical experiment. Three odors (isoamyl acetate, butanol and pyridine) were presented to twenty subjects. Each odor was delivered three times with five values of duty cycles. After each stimulation, the subjects were asked to estimate the intensity of the stimulus on a 10 point scale, ranging from 0 (undetectable) to 9 (very strong). Results show a main effect of the duty cycles on the intensity ratings for all tested odors. PMID:26710120

  10. Stark widths and shifts for spectral lines of Sn IV

    NASA Astrophysics Data System (ADS)

    de Andrés-García, I.; Alonso-Medina, A.; Colón, C.

    2016-01-01

    In this paper, we present theoretical Stark widths and shifts calculated corresponding to 66 spectral lines of Sn IV. We use the Griem semi-empirical approach and the COWAN computer code. For the intermediate coupling calculations, the standard method of least-squares fitting from experimental energy levels was used. Data are presented for an electron density of 1017 cm-3 and temperatures T = 1.1-5.0 (104 K). The matrix elements used in these calculations have been determined from 34 configurations of Sn IV: 4d10ns(n = 5-10), 4d10nd(n = 5-8), 4d95s2, 4d95p2, 4d95s5d, 4d85s5p2 and 4d105g for even parity and 4d10np(n = 5-8), 4d10nf (n = 4-6), 4d95snp(n = 5-8), 4d85s25p and 4d95snf (n = 4-10) for odd parity. Also, in order to test the matrix elements used in our calculations, we present calculated values of radiative lifetimes of 14 levels of Sn IV. There is good agreement between our calculations and the experimental radiative lifetimes obtained from the bibliography. The spectral lines of Sn IV are observed in UV spectra of HD 149499 B obtained with the Far Ultraviolet Spectroscopic Explorer, the Goddard High Resolution Spectrograph and the International Ultraviolet Explorer. Theoretical trends of the Stark broadening parameter versus the temperature for relevant lines are presented. Also our values of Stark broadening parameters have been compared with the data available in the bibliography.

  11. Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

    SciTech Connect

    Ikeda, Kazuhiro; Tsukui, Tohru; Imazawa, Yukiko; Horie-Inoue, Kuniko; Inoue, Satoshi

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Conditional transgenic mice expressing constitutively active estrogen receptor {alpha} (caER{alpha}) in chondrocytes were developed. Black-Right-Pointing-Pointer Expression of caER{alpha} in chondrocytes impaired longitudinal bone growth in mice. Black-Right-Pointing-Pointer caER{alpha} affects chondrocyte proliferation and differentiation. Black-Right-Pointing-Pointer This mouse model is useful for understanding the physiological role of ER{alpha}in vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caER{alpha}{sup ColII}, expressing constitutively active mutant estrogen receptor (ER) {alpha} in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caER{alpha}{sup ColII} mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caER{alpha}{sup ColII} mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caER{alpha}{sup ColII} mice. These results suggest that ER{alpha} is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

  12. Alpha Magnetic Spectrometer (AMS) Overview

    NASA Video Gallery

    The Alpha Magnetic Spectrometer (AMS) is flying to the station on STS-134. The AMS experiment is a state-of-the-art particle physics detector being operated by an international team composed of 60 ...

  13. Genetics Home Reference: alpha thalassemia

    MedlinePlus

    ... in each cell. Each copy is called an allele. For each gene, one allele is inherited from a person's father, and the ... person's mother. As a result, there are four alleles that produce alpha-globin. The different types of ...

  14. International Space Station (ISS) Alpha

    NASA Technical Reports Server (NTRS)

    1994-01-01

    An artist's concept of a fully deployed International Space Station (ISS) Alpha. The ISS-A is a multidisciplinary laboratory, technology test bed, and observatory that will provide an unprecedented undertaking in scientific, technological, and international experiments.

  15. Detecting Alpha-1 Antitrypsin Deficiency.

    PubMed

    Stoller, James K

    2016-08-01

    Alpha-1 antitrypsin deficiency is a widely underrecognized condition, with evidence of persisting long diagnostic delays and patients' frequent need to see multiple physicians before initial diagnosis. Reasons for underrecognition include inadequate understanding of alpha-1 antitrypsin deficiency by physicians and allied health care providers; failure to implement available, guideline-based practice recommendations; and the belief that effective therapy is unavailable. Multiple studies have described both the results of screening and targeted detection of individuals with alpha-1 antitrypsin deficiency, with both varying strategies employed to identify at-risk individuals and varying results of testing. Also, various strategies to enhance detection of affected individuals have been examined, including use of the electronic medical record to prompt testing and empowerment of allied health providers, especially respiratory therapists, to promote testing for alpha-1 antitrypsin deficiency. Such efforts are likely to enhance detection with the expected result that the harmful effects of delayed diagnosis can be mitigated. PMID:27564667

  16. GWD-LR: a satellite-based global database of river channel width

    NASA Astrophysics Data System (ADS)

    Yamazaki, Dai; O'Loughlin, Fiachra; Trigg, Mark; Bates, Paul

    2015-04-01

    River width is a fundamental parameter of river hydrodynamic simulations, but no global-scale river width database based on observed water bodies has yet been developed. Here we present a new algorithm that automatically calculates river width from satellite-based water masks and flow direction maps. The Global Width Database for Large Rivers (GWD-LR) is developed by applying the algorithm to the SRTM Water Body Database and the HydroSHEDS flow direction map. Both bank-to-bank river width and effective river width excluding islands are calculated for river channels between 60S and 60N. The effective river width of GWD-LR is compared with existing river width databases for the Congo and Mississippi Rivers. The effective river width of the GWD-LR is slightly narrower compared to the existing databases, but the relative difference is within +/-20% for most river channels. As the river width of the GWD-LR is calculated along the river channels of the HydroSHEDS flow direction map, it is relatively straightforward to apply the GWD-LR to global- and continental-scale river modeling.

  17. Alpha decay in electron surrounding

    SciTech Connect

    Igashov, S. Yu.; Tchuvil’sky, Yu. M.

    2013-12-15

    The influence of atomic electron shells on the constant of alpha decay of heavy and mediummass nuclei was considered in detail. A method for simultaneously taking into account the change in the potential-barrier shape and the effect of reflection of a diverging Coulomb wave in the classically allowed region was developed. The ratios of decay probabilities per unit time for a bare nucleus and the respective neutral atom were found for some alpha-decaying isotopes.

  18. Characterization of salivary alpha-amylase binding to Streptococcus sanguis

    SciTech Connect

    Scannapieco, F.A.; Bergey, E.J.; Reddy, M.S.; Levine, M.J. )

    1989-09-01

    The purpose of this study was to identify the major salivary components which interact with oral bacteria and to determine the mechanism(s) responsible for their binding to the bacterial surface. Strains of Streptococcus sanguis, Streptococcus mitis, Streptococcus mutans, and Actinomyces viscosus were incubated for 2 h in freshly collected human submandibular-sublingual saliva (HSMSL) or parotid saliva (HPS), and bound salivary components were eluted with 2% sodium dodecyl sulfate. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western transfer, alpha-amylase was the prominent salivary component eluted from S. sanguis. Studies with {sup 125}I-labeled HSMSL or {sup 125}I-labeled HPS also demonstrated a component with an electrophoretic mobility identical to that of alpha-amylase which bound to S. sanguis. Purified alpha-amylase from human parotid saliva was radiolabeled and found to bind to strains of S. sanguis genotypes 1 and 3 and S. mitis genotype 2, but not to strains of other species of oral bacteria. Binding of ({sup 125}I)alpha-amylase to streptococci was saturable, calcium independent, and inhibitable by excess unlabeled alpha-amylases from a variety of sources, but not by secretory immunoglobulin A and the proline-rich glycoprotein from HPS. Reduced and alkylated alpha-amylase lost enzymatic and bacterial binding activities. Binding was inhibited by incubation with maltotriose, maltooligosaccharides, limit dextrins, and starch.

  19. The Role of Neutrophils in Alpha-1 Antitrypsin Deficiency.

    PubMed

    McCarthy, Cormac; Reeves, Emer P; McElvaney, Noel G

    2016-08-01

    Alpha-1 antitrypsin deficiency (AATD) is characterized by low levels of circulating alpha-1 antitrypsin and an increased risk for emphysema, liver disease, and panniculitis. The reduced levels of alpha-1 antitrypsin in AATD predispose the lung to unopposed proteolytic activity, predominantly from neutrophil-derived proteases, chiefly neutrophil elastase. This leads to emphysema. The mechanisms subtending the liver disease are less well understood, but are probably due to a "gain-of function" inflammatory process in the liver, stoked by intracellular retention of aberrantly folded alpha-1 antitrypsin. The panniculitis associated with AATD is most likely due to unopposed proteolytic activity in the skin. Although AATD has been traditionally viewed as a condition arising from a protease-antiprotease imbalance in the lung, it is increasingly recognized that AATD is an inflammatory disorder, both in the lung and in the extrapulmonary manifestations associated with the condition. This inflammation is predominantly neutrophil driven, and there are several alpha-1 antitrypsin-related mechanisms involved in potentiating this neutrophilic response. The rationale for AAT augmentation therapy in AATD is classically based on restoring the antiprotease balance in the lung, but its beneficial effects may also be exerted systemically, further exposing the pathogenesis of AATD-related disease and indicating a potential usage for alpha-1 antitrypsin in other inflammatory conditions. PMID:27564664

  20. Characterization of salivary alpha-amylase binding to Streptococcus sanguis.

    PubMed Central

    Scannapieco, F A; Bergey, E J; Reddy, M S; Levine, M J

    1989-01-01

    The purpose of this study was to identify the major salivary components which interact with oral bacteria and to determine the mechanism(s) responsible for their binding to the bacterial surface. Strains of Streptococcus sanguis, Streptococcus mitis, Streptococcus mutans, and Actinomyces viscosus were incubated for 2 h in freshly collected human submandibular-sublingual saliva (HSMSL) or parotid saliva (HPS), and bound salivary components were eluted with 2% sodium dodecyl sulfate. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western transfer, alpha-amylase (EC 3.2.1.1) was the prominent salivary component eluted from S. sanguis. Studies with 125I-labeled HSMSL or 125I-labeled HPS also demonstrated a component with an electrophoretic mobility identical to that of alpha-amylase which bound to S. sanguis. Purified alpha-amylase from human parotid saliva was radiolabeled and found to bind to strains of S. sanguis genotypes 1 and 3 and S. mitis genotype 2, but not to strains of other species of oral bacteria. Binding of [125I]alpha-amylase to streptococci was saturable, calcium independent, and inhibitable by excess unlabeled alpha-amylases from a variety of sources, but not by secretory immunoglobulin A and the proline-rich glycoprotein from HPS. Reduced and alkylated alpha-amylase lost enzymatic and bacterial binding activities. Binding was inhibited by incubation with maltotriose, maltooligosaccharides, limit dextrins, and starch. Images PMID:2788139