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Sample records for induced 150sm cross

  1. (n,2n) and (n,3n) cross sections of neutron-induced reactions on 150Sm for En from threshold to 35 MeV

    SciTech Connect

    Dashdorj, D; Mitchell, G; Kawano, T; Becker, J; Wu, C; Devlin, M; Fotiades, N; Nelson, R; Kunieda, S

    2009-03-16

    Cross-section measurements were made of prompt discrete {gamma}-ray production as a function of incident neutron energy (E{sub n} = 1 to 35 MeV) on a {sup 150}Sm sample fo 1550 mg/cm{sup 2} of Sm{sub 2}O{sub 3} enriched to 95.6% in {sup 150}Sm. Results are compared with enhanced Hauser-Feshbach model calculations including the pre-equilibrium reactions. Energetic neutrons were delivered by the Los Alamos Neutron Science Center facility. The prompt-reaction {gamma} rays were detected with the Compton-suppressed Germanium Array for Neutron Induced Excitations (GEANIE). Incident neutron energies were determined by the time-of-flight technique. Excitation functions for thirteen individual {gamma}-rays up to E{sub x} = 0.8 MeV in {sup 149}Sm and one {gamma}-ray transition between the first excited and ground state in {sup 148}Sm were measured. Partial {gamma}-ray cross sections were calculated using GNASH, an enhanced Hauser-Feshbach statistical nuclear reaction model code, and compared with the experimental results. The particle transmission coefficients were calculated with new systematic 'global' optical model potential parameters. The coupled-channel optical model based on the soft rotor model was employed to calculate the particle transmission coefficients. The pre-equilibrium part of the spin distribution in {sup 150}Sm was calculated using the quantum mechanical theory of Feshbach, Kerman, and Koonin (FKK) and incorporated into the GNASH reaction model code. the partial cross sections for discrete {gamma}-ray cascade paths leading to the ground state in {sup 149}Sm and {sup 148}Sm have been summed (without double counting) to estimate lower limits for reaction cross sections. These lower limits are combined with Hauser-Feshbach model calculations to deduce the reaction channel cross sections. These reaction channel cross sections agree with previously measured experimental and ENDF/B-VII evaluations.

  2. Inelastic partial {gamma}-ray cross sections of {sup 150}Sm+n reactions for E{sub n} = 1-15 MeV

    SciTech Connect

    Dashdorj, D.; Kawano, T.; Devlin, M.; Fotiades, N.; Nelson, R. O.; Mitchell, G. E.; Becker, J. A.; Garrett, P. E.; Kunieda, S.

    2011-06-28

    The {sup 150}Sm(n,n'{gamma}) reaction was measured from E{sub n} = 1 to 15 MeV at the Los Alamos Neutron Science Cemter (LANSCE). The {gamma} rays were detected with the Compton-suppressed Germanium Array for Neutron Induced Excitations (GEANIE). Measured {gamma}-ray excitation functions were converted to partial {gamma}-ray cross sections, Twenty four individual {gamma}-rays up to E{sub x} = 1.8 MeV in {sup 150}Sm were measured. Results are compared with enhanced Hauser Feshbach model calculations: the spin distribution in the pre-equilibrium reaction is calculated with the quantum mechanical model of Feshbach, Kerman and Koonin. The particle transmission coefficients were calculated with two different global optical model potential parameter sets. We employed the coupled-channel optical model based on the soft rotor model and with spherical potential.

  3. Measurement of 150-Sm(n,2ngammai) 149-Sm cross sections between threshold and 20 MeV

    SciTech Connect

    Cooper, J; Becker, J; Dashdorj, D; Dietrich, F S; Garrett, P; Hoffman, R; Younes, W; Nelson, R; Devlin, M; Fotiades, N

    2004-08-02

    Absolute partial {gamma}-ray cross sections for the production of discrete {gamma}-rays from the reaction {sup 150}Sm(n,2n{gamma}{sub i}){sup 149}Sm were measured using the GEANIE {gamma}-ray spectrometer coupled with the intense white neutron source at WNR/LANSCE. The measurements were made for incident neutron energies between threshold (8.04 MeV) and 20 MeV. The partial cross sections for 21 {gamma}-rays were extracted from the data. Of these, 17 were compared to calculations performed using the enhanced Hauser-Feshbach code STAPRE. The partial {gamma}-ray cross sections of the observed parallel decay paths to the ground state were summed, forming a lower bound for the (n,2n) reaction channel. A combination of theory and experiment was then used to deduce the (n,2n) reaction channel cross section.

  4. Investigation of discrete states and quasidiscrete structures observed in 150Sm and 152Sm using the (p ,t γ ) reaction

    NASA Astrophysics Data System (ADS)

    Humby, P.; Simon, A.; Beausang, C. W.; Allmond, J. M.; Burke, J. T.; Casperson, R. J.; Chyzh, R.; Dag, M.; Gell, K.; Hughes, R. O.; Koglin, J.; McCleskey, E.; McCleskey, M.; Ota, S.; Ross, T. J.; Saastamoinen, A.; Tarlow, T.; Vyas, G.

    2016-12-01

    New levels and γ -ray transitions were identified in Sm,152150 utilizing the (p ,t ) reaction and particle-γ coincidence data. A large, peak-like structure observed between 2.3-3.0 MeV in excitation energy in the triton energy spectra was also investigated. The orbital angular-momentum transfer was probed by comparing the experimental angular distributions of the outgoing tritons to calculated distorted wave Born approximation curves. The angular distributions of the outgoing tritons populating the peak-like structure are remarkably similar in the two reactions and are significantly different from the angular distributions associated with the nearby continuum region. Relative partial cross sections for the observed levels, angle averaged between 34 and 58 degrees, were measured. In 150Sm, 39(4)% of the strength of the peak-like structure could be accounted for by the observed discrete states. This compares with a value of 93(15)% for 152Sm.

  5. Energy loss of 107Ag, 109Ag, and 150Sm in Ni and Au

    NASA Astrophysics Data System (ADS)

    Ribas, R. V.; Seale, W. A.; Roney, W. A.; Szanto, E. M.

    1980-04-01

    The stopping pow´er of 107Ag, 109Ag, and 150Sm in nickel and gold was measured as a preliminary test of a new technique for measuring energy loss based on the γ-ray Doppler shift. The analysis of the data was based on the theories of Lindhard, Scharff, and Schiott for nuclear and electronic stopping. The results are compared with the semiempirical predictions of Northcliffe and Schilling and the Lindhard-Scharff-Schiott theory.

  6. Investigation of discrete states and quasidiscrete structures observed in 150Sm and 152Sm using the ( p,tγ) reaction

    DOE PAGES

    Peter, Humby; Simon, Anna; Beausang, C. W.; ...

    2016-01-01

    New levels and γ-ray transitions were identified in 150,152Sm utilizing the (p,t) reaction and particle-γ coincidence data. A large, peak-like structure observed between 2.3–3.0 MeV in excitation energy in the triton energy spectra was also investigated. The orbital angular-momentum transfer was probed by comparing the experimental angular distributions of the outgoing tritons to calculated distorted wave Born approximation curves. The angular distributions of the outgoing tritons populating the peak-like structure are remarkably similar in the two reactions and are significantly different from the angular distributions associated with the nearby continuum region. Relative partial cross sections for the observed levels, anglemore » averaged between 34 and 58 degrees, were measured. In 150Sm, 39(4)% of the strength of the peak-like structure could be accounted for by the observed discrete states. This compares with a value of 93(15)% for 152Sm« less

  7. High resolution 148Nd(3He,nγ) two proton stripping reaction and the structure of the 02+ state in 150Sm

    NASA Astrophysics Data System (ADS)

    Sharpey-Schafer, J. F.; Papka, P.; Bvumbi, S. P.; Jones, P. M.; Vymers, P.; Bucher, T. D.; Dinoko, T. S.; Easton, J. L.; Herbert, M. S.; Kheswa, B. V.; Khumalo, N.; Lawrie, E. A.; Lawrie, J. J.; Majola, S. N. T.; Ndayishimye, J.; Negi, D.; Noncolela, S. P.; Orce, J. N.; Shirinda, O.; Sithole, P.; Standkiewicz, M. A.; Wiedeking, M.

    2014-04-01

    The challenge of achieving high resolution in binary reactions involving an outgoing high energy neutron is solved by detecting the γ-ray decay of populated excited states in an array of escape suppressed HPGe detectors in coincidence with fast neutrons detected in a wall of scintillator detectors 2m down beam of the target. The selectivity of the arrangement is of the order of 1 in 1000. The time-of-flight difference is sufficient to separate fast neutrons from direct reactions from a large background of statistical neutrons from fusion-evaporation reactions. Our interest is in the wavefunction of the 02+ state at 740 keV in the N=88 nucleus 150Sm which, with the 02+ state in 100Ru, are the only two excited states observed in 2β2ν double β-decay.

  8. The {sup 150}Nd({sup 3}He,t) and {sup 150}Sm(t,{sup 3}He) reactions with applications to {beta}{beta} decay of {sup 150}Nd

    SciTech Connect

    Guess, C. J.; Brown, B. A.; Deaven, J. M.; Hitt, G. W.; Meharchand, R.; Zegers, R. G. T.; Adachi, T.; Fujita, H.; Hatanaka, K.; Hirota, K.; Ishikawa, D.; Matsubara, H.; Okamura, H.; Ong, H. J.; Suzuki, T.; Tamii, A.; Yosoi, M.; Zenihiro, J.; Akimune, H.; Algora, A.

    2011-06-15

    The {sup 150}Nd({sup 3}He,t) reaction at 140 MeV/u and {sup 150}Sm(t,{sup 3}He) reaction at 115 MeV/u were measured, populating excited states in {sup 150}Pm. The transitions studied populate intermediate states of importance for the (neutrinoless) {beta}{beta} decay of {sup 150}Nd to {sup 150}Sm. Monopole and dipole contributions to the measured excitation-energy spectra were extracted by using multipole decomposition analyses. The experimental results were compared with theoretical calculations obtained within the framework of the quasiparticle random-phase approximation, which is one of the main methods employed for estimating the half-life of the neutrinoless {beta}{beta} decay (0{nu}{beta}{beta}) of {sup 150}Nd. The present results thus provide useful information on the neutrino responses for evaluating the 0{nu}{beta}{beta} and 2{nu}{beta}{beta} matrix elements. The 2{nu}{beta}{beta} matrix element calculated from the Gamow-Teller transitions through the lowest 1{sup +} state in the intermediate nucleus is maximally about half that deduced from the half-life measured in 2{nu}{beta}{beta} direct counting experiments, and at least several transitions through 1{sup +} intermediate states in {sup 150}Pm are required to explain the 2{nu}{beta}{beta} half-life. Because Gamow-Teller transitions in the {sup 150}Sm(t,{sup 3}He) experiment are strongly Pauli blocked, the extraction of Gamow-Teller strengths was complicated by the excitation of the 2({h_bar}/2{pi}){omega}, {Delta}L=0, {Delta}S=1 isovector spin-flip giant monopole resonance (IVSGMR). However, the near absence of Gamow-Teller transition strength made it possible to cleanly identify this resonance, and the strength observed is consistent with the full exhaustion of the non-energy-weighted sum rule for the IVSGMR.

  9. Exertional and CrossFit-Induced Rhabdomyolysis.

    PubMed

    Meyer, Michelle; Sundaram, Sneha; Schafhalter-Zoppoth, Ingeborg

    2017-07-14

    Few publications of exercise-induced rhabomyolysis currently exist in the medical literature besides case reports. However, this condition can be severe, resulting in hospitalization and IV fluid administration to prevent serious sequelae. This report describes a case of exercise-induced rhabdomyolysis caused by a CrossFit workout. A 31-year-old female presented with 2 days of bilateral upper extremity pain and soreness, which began 2 days after she completed a CrossFit workout. Workup revealed an elevated creatine phosphokinase (CPK) of 18 441 U/L, consistent with exercise-induced rhabdomyolysis, and elevated liver function tests and elevated D-dimer, although her renal function was normal. She was hospitalized for 2 days and treated with IV fluids. This case report demonstrates that CrossFit exercises can lead to rhabdomyolysis, highlighting a condition that may be underdiagnosed and underreported.

  10. Analysis of random induced cross polarization

    NASA Astrophysics Data System (ADS)

    McGrath, Daniel T.

    1992-03-01

    Streamlined radomes will always introduce depolarization because of the fact that any material surface viewed at an oblique angle has different transmission coefficients for fields polarized parallel and perpendicular to the plane of incidence, a phenomenon known as divorce. The cross polarized fields are similar in nature to those responsible for Condon lobes of parabolic reflectors, and which are known to make those antennas susceptible to cross polarization jamming. The relative strength of those lobes is directly related to the amount of divorce, and is quite sensitive to the phase difference of parallel and perpendicular transmission coefficients. A mere 20 deg of phase divorce has a comparable effect to 3 dB of amplitude divorce. This paper presents a detailed analysis for general radome shapes, based on geometrical optics (ray tracing). Example results are presented for conical and tangent ogive radome geometries used in conjunction with a circular-aperture antenna that is mechanically scanned. The results show that when the antenna is scanned off axis, the cross polarized pattern changes from a Condon lobe structure to a difference pattern in the direction orthogonal to the axis of scan, e.g.: under azimuth scanning the cross polarized sum pattern resembles an elevation difference pattern, while the cross polarized elevation difference resembles a sum beam. Hence, interference in the cross polarization will introduce a tracking error in the direction orthogonal to the scan plane.

  11. Flavivirus-induced antibody cross-reactivity

    PubMed Central

    Mansfield, Karen L.; Horton, Daniel L.; Johnson, Nicholas; Li, Li; Barrett, Alan D. T.; Smith, Derek J.; Galbraith, Sareen E.; Solomon, Tom

    2011-01-01

    Dengue viruses (DENV) cause countless human deaths each year, whilst West Nile virus (WNV) has re-emerged as an important human pathogen. There are currently no WNV or DENV vaccines licensed for human use, yet vaccines exist against other flaviviruses. To investigate flavivirus cross-reactivity, sera from a human cohort with a history of vaccination against tick-borne encephalitis virus (TBEV), Japanese encephalitis virus (JEV) and yellow fever virus (YFV) were tested for antibodies by plaque reduction neutralization test. Neutralization of louping ill virus (LIV) occurred, but no significant neutralization of Murray Valley encephalitis virus was observed. Sera from some individuals vaccinated against TBEV and JEV neutralized WNV, which was enhanced by YFV vaccination in some recipients. Similarly, some individuals neutralized DENV-2, but this was not significantly influenced by YFV vaccination. Antigenic cartography techniques were used to generate a geometric illustration of the neutralization titres of selected sera against WNV, TBEV, JEV, LIV, YFV and DENV-2. This demonstrated the individual variation in antibody responses. Most sera had detectable titres against LIV and some had titres against WNV and DENV-2. Generally, LIV titres were similar to titres against TBEV, confirming the close antigenic relationship between TBEV and LIV. JEV was also antigenically closer to TBEV than WNV, using these sera. The use of sera from individuals vaccinated against multiple pathogens is unique relative to previous applications of antigenic cartography techniques. It is evident from these data that notable differences exist between amino acid sequence identity and mapped antigenic relationships within the family Flaviviridae. PMID:21900425

  12. Actinide neutron-induced fission cross section measurements at LANSCE

    SciTech Connect

    Tovesson, Fredrik K; Laptev, Alexander B; Hill, Tony S

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications in a wide energy range from sub-thermal energies up to 200 MeV. A parallel-plate ionization chamber are used to measure fission cross sections ratios relative to the {sup 235}U standard while incident neutron energies are determined using the time-of-flight method. Recent measurements include the {sup 233,238}U, {sup 239-242}Pu and {sup 243}Am neutron-induced fission cross sections. Obtained data are presented in comparison with ex isting evaluations and previous data.

  13. Functional polymer laminates from hyperthermal hydrogen induced cross-linking.

    PubMed

    Thompson, David B; Trebicky, Tomas; Crewdson, Patrick; McEachran, Matthew J; Stojcevic, Goran; Arsenault, Gilles; Lau, Woon M; Gillies, Elizabeth R

    2011-12-20

    The use of a hyperthermal hydrogen induced cross-linking process to prepare laminates comprising polypropylene, poly(isobutylene-co-isoprene), and poly(vinyl acetate) is described. In this new, milder alternative to conventional plasma techniques, neutral molecular hydrogen projectiles were used to create carbon radicals on impacted surfaces by collision-induced dissociation of C-H bonds, and this process was used to cross-link polymers on a polypropylene surface. It was demonstrated that multiple layers of cross-linked materials could be added, creating polymer laminates with each layer introducing new functionalities and properties. In particular, the present work shows that the process is largely nondestructive toward ester functionalities. First, the esters were grafted to become nonleachable. Then, the esters were subsequently hydrolyzed to convert the surface from hydrophobic to hydrophilic. Afterward, the esters could be recovered by simple esterification demonstrating that further chemical transformations were possible.

  14. Cross-correlation—an objective tool to indicate induced seismicity

    NASA Astrophysics Data System (ADS)

    Oprsal, Ivo; Eisner, Leo

    2014-03-01

    Differentiation between natural and induced seismicity is crucial for the ability to safely and soundly carry out various underground experiments and operations. This paper defines an objective tool for one of the criteria used to discriminate between natural and induced seismicity. The qualitative correlation between earthquake rates and the injected volume has been an established tool for investigating the possibility of induced, or triggered, seismicity. We derive mathematically, and verify using numerical examples, that the definition of normalized cross-correlation (NCC) between positive random functions exhibits high values with a limit equal to one, if these functions (such as earthquake rates and injection volumes) have a large mean and low standard deviation. In such a case, the high NCC values do not necessarily imply temporal relationship between the phenomena. Instead of positive-value time histories, the functions with their running mean subtracted should be used for cross-correlation. The NCC of such functions (called here NCCEP) may be close to zero, or may oscillate between positive and negative values in cases where seismicity is not related to injection. We apply this method for case studies of seismicity in Colorado, the United Kingdom, Switzerland and south-central Oklahoma, and show that NCCEP reliably determines induced seismicity. Finally, we introduce a geomechanical model explaining the positive cross-correlation observed in the induced seismicity data sets.

  15. Neutron-Induced Cross Sections Measurements of Calcium

    SciTech Connect

    Guber, Klaus H; Kopecky, S.; Schillebeeckx, P.; Kauwenberghs, K.; Siegler, P.

    2013-01-01

    To support the US Department of Energy Nuclear Criticality Safety Program neutron induced cross section experiments were performed at the Geel Electron Linear Accelerator of the Institute for Reference Material and Measurements of the Joint Research Centers, European Union. Neutron capture and transmission measurements were carried out using a metallic calcium sample. The obtained data will be used for a new calcium evaluation, which will be submitted with its covariances to the ENDBF/B nuclear data base.

  16. Theoretical cross sections of tantalum on neutron induced reactions

    NASA Astrophysics Data System (ADS)

    Siddik, Tarik

    2016-11-01

    Neutron-induced cross-sections for the stable isotope 181Ta, in the energy region up to 20 MeV have been calculated. Statistical model calculations, based on the Hauser-Feshbach formalism, have been carried out using the TALYS-1.0 and were compared with available experimental data in the literature and with ENDF/B-VII, T = 300 K; JENDL-3.3, T = 300 K and JEFF-3.1, T = 300 K evaluated libraries.

  17. Neutron-induced Cross Section Measurements of Calcium

    NASA Astrophysics Data System (ADS)

    Guber, K.; Kopecky, S.; Schillebeeckx, P.; Kauwenberghs, K.; Siegler, P.

    2014-05-01

    To support the US Department of Energy Nuclear Criticality Safety Program, neutron-induced cross section experiments were performed at the Geel Electron Linear Accelerator of the Institute for Reference Material and Measurements of the Joint Research Centers, European Union. Neutron capture and transmission measurements were carried out using a metallic calcium sample. The measured data will be used for a new calcium evaluation, which will be submitted with covariances to the ENDF/B nuclear data library.

  18. Measuring Neutron-Induced Reaction Cross Sections without Neutrons

    NASA Astrophysics Data System (ADS)

    Bernstein, L. A.; Schiller, A.; Cooper, J. R.; Hoffman, R. D.; McMahan, M. A.; Fallon, P.; Macchiavelli, A. O.; Mitchell, G.; Tavukcu, E.; Guttormsen, M.

    2003-04-01

    Neutron-induced reactions on radioactive nuclei play a significant role in nuclear astrophysics and many other applied nuclear physics topics. However, the majority of these cross sections are impossible to measure due to the high-background of the targets and the low-intensity of neutron beams. We have explored the possibility of using charged-particle transfer reactions to form the same "pre-compound" nucleus as one formed in a neutron-induced reaction in order to measure the relative decay probabilities of the nucleus as a function of energy. Multiplying these decay probabilities by the neutron absorption cross section will then produce the equivalent neutron-induced reaction cross section. In this presentation I will explore the validity of this "surrogate reaction" technique by comparing results from the recent 157Gd(3He,axng)156-xGd experiment using STARS (Silicon Telescope Array for Reaction Studies) at GAMMASPHERE with reaction model calculations for the 155Gd(n,xng)156-xGd. This work was funded by the US Department of Energy under contracts number W-7405-ENG-48 (LLNL), AC03-76SF00098 (LBNL) and the Norwegian Research Council (Oslo).

  19. Cross-Reactive Myelin Antibody Induces Renal Disease

    PubMed Central

    Peterson, Lisa K.; Masaki, Takahisa; Wheelwright, Steven R.; Tsunoda, Ikuo; Fujinami, Robert S.

    2011-01-01

    Experimental autoimmune encephalomyelitis (EAE) is an autoimmune model for multiple sclerosis (MS). Previously, we reported renal immunoglobulin (Ig) deposition in mice with myelin oligodendrocyte glycoprotein (MOG92-106) induced progressive-EAE and naïve mice injected with MOG92-106 hybridoma cells producing antibody that cross-reacts with various autoantigens including double-stranded DNA. To assess whether MOG92-106 antibodies actually induce kidney changes, the extent of renal Ig deposition and changes in glomerular histology and filtration were investigated. Mice with progressive-EAE exhibited Ig deposition, glomerular hypercellularity and proteinuria indicating kidney dysfunction. MOG92-106 hybridoma cell injected mice also had Ig in the kidneys and proteinuria. Therefore, sensitization with MOG92-106 and transfer of MOG92-106 antibodies can induce both central nervous system and renal pathology. The renal involvement reported in MS is believed to occur as a side effect of nephrotoxic drugs or neurogenic bladder. Our results demonstrate that an autoimmune response against myelin could induce pathologic changes in the kidney and may help explain renal changes reported in patients with progressive MS. PMID:18608179

  20. Aluminum induces cross-resistance of potato to Phytophthora infestans.

    PubMed

    Arasimowicz-Jelonek, Magdalena; Floryszak-Wieczorek, Jolanta; Drzewiecka, Kinga; Chmielowska-Bąk, Jagna; Abramowski, Dariusz; Izbiańska, Karolina

    2014-03-01

    The phenomenon of cross-resistance allows plants to acquire resistance to a broad range of stresses after previous exposure to one specific factor. Although this stress-response relationship has been known for decades, the sequence of events that underpin cross-resistance remains unknown. Our experiments revealed that susceptible potato (Solanum tuberosum L. cv. Bintje) undergoing aluminum (Al) stress at the root level showed enhanced defense responses correlated with reduced disease symptoms after leaf inoculation with Phytophthora infestans. The protection capacity of Al to subsequent stress was associated with the local accumulation of H2O2 in roots and systemic activation of salicylic acid (SA) and nitric oxide (NO) dependent pathways. The most crucial Al-mediated changes involved coding of NO message in an enhanced S-nitrosothiol formation in leaves tuned with an abundant SNOs accumulation in the main vein of leaves. Al-induced distal NO generation was correlated with the overexpression of PR-2 and PR-3 at both mRNA and protein activity levels. In turn, after contact with a pathogen we observed early up-regulation of SA-mediated defense genes, e.g. PR1, PR-2, PR-3 and PAL, and subsequent disease limitation. Taken together Al exposure induced distal changes in the biochemical stress imprint, facilitating more effective responses to a subsequent pathogen attack.

  1. Nanoparticles can cross mouse placenta and induce trophoblast apoptosis.

    PubMed

    Huang, Jian-Pei; Hsieh, Patrick C H; Chen, Chen-Yu; Wang, Tao-Yeuan; Chen, Pei-Chun; Liu, Chang-Ching; Chen, Chen-Chun; Chen, Chie-Pein

    2015-12-01

    The effects of nanoparticles on pregnancy remain unclear. In this study, we investigate whether nanoparticles of a specific size can cross the placenta and affect trophoblast function. Fluorescently labelled carboxylate-modified polystyrene beads with diameters of 20, 40, 100, 200, and 500 nm were chosen as model particles. In vitro, trophoblast cell line (3A-Sub-E) or primary culture of term trophoblasts was used for nanoparticle uptake analysis using flow cytometry, confocal microscopy, BrdU proliferation assay and analysis of cell apoptosis using Western blot. Intravenous injection of nanoparticles into pregnant mice at embryonic day 17 was used to study whether nanoparticles can cross the placenta. The mouse placentas were collected and quantitatively analyzed using high-performance liquid chromatography for nanoparticle uptake. Fluorescent polystyrene particles with diameters of up to 500 nm were taken up by the placenta and were able to cross the placental barrier. The fluorescent polystyrene particles were observed in various organs of fetuses after 4 h of administration to pregnant mice. The nanoparticle uptake by placental tissue was significantly increased in nanoparticles with a diameter of 40 nm. No linear association was evident between nanoparticle size and uptake. Nanoparticles with diameters of 20 nm (200 μg/ml) and 40 nm (500 μg/ml) could induce trophoblast cell apoptosis with increased cleaved caspase 3 and reduced cell proliferation. Our findings suggest that nanoparticles can cross the placenta and be taken up by fetal organs. Certain concentrations of carboxylate-modified polystyrene nanoparticles may be cytotoxic to trophoblasts, which could alter placental function. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Induced Collagen Cross-Links Enhance Cartilage Integration

    PubMed Central

    Athens, Aristos A.; Makris, Eleftherios A.; Hu, Jerry C.

    2013-01-01

    Articular cartilage does not integrate due primarily to a scarcity of cross-links and viable cells at the interface. The objective of this study was to test the hypothesis that lysyl-oxidase, a metalloenzyme that forms collagen cross-links, would be effective in improving integration between native-to-native, as well as tissue engineered-to-native cartilage surfaces. To examine these hypotheses, engineered cartilage constructs, synthesized via the self-assembling process, as well as native cartilage, were implanted into native cartilage rings and treated with lysyl-oxidase for varying amounts of time. For both groups, lysyl-oxidase application resulted in greater apparent stiffness across the cartilage interface 2–2.2 times greater than control. The construct-to-native lysyl-oxidase group also exhibited a statistically significant increase in the apparent strength, here defined as the highest observed peak stress during tensile testing. Histology indicated a narrowing gap at the cartilage interface in lysyl-oxidase treated groups, though this alone is not sufficient to indicate annealing. However, when the morphological and mechanical data are taken together, the longer the duration of lysyl-oxidase treatment, the more integrated the interface appeared. Though further data are needed to confirm the mechanism of action, the enhancement of integration may be due to lysyl-oxidase-induced pyridinoline cross-links. This study demonstrates that lysyl-oxidase is a potent agent for enhancing integration between both native-to-native and native-to-engineered cartilages. The fact that interfacial strength increased manifold suggests that cross-linking agents should play a significant role in solving the difficult problem of cartilage integration. Future studies must examine dose, dosing regimen, and cellular responses to lysyl-oxidase to optimize its application. PMID:23593295

  3. Measurement of Neutrino Induced Quasi-Elastic Cross Section

    NASA Astrophysics Data System (ADS)

    Kim, Jae

    2006-04-01

    The measurement of the weak mixing angle is the goal, using the data collected in the NOMAD experiment at CERN. Studying the neutrino induced Quasi-Elastic (QE) scattering, in which neutrino hits neutron and results in a muon and a proton, would enhance our understanding of the `higher-twist effect' -- an effect that parameterizes the weak mixing angle. Toward this, I developed a likelihood probability density function that enabled me to eliminate a significant portion of the background, resonance and deep inelastic scattering events. As the Monte Carlo (MC) is only reliable to a precision not better than 15 -- 20 percent, I developed several techniques to make sure that MC and DATA agreed around 5 percent. The axial mass and QE cross section can then be calculated. Techniques and the preliminary results relevant to the calculation will be presented.

  4. Behavioral cross-sensitization between morphine-induced locomotion and sodium depletion-induced salt appetite.

    PubMed

    Na, Elisa S; Morris, Michael J; Johnson, Alan Kim

    2009-10-01

    In general terms, sensitization refers to the capacity of a repetitive stimulus of fixed strength to produce a progressive increase in the magnitude of a response with each stimulation. In the addiction literature cross-sensitization is the capacity of an agent with abuse potential to sensitize a behavioral response induced by another stimulus. In the present experiments we examined the effects of morphine pretreatment on furosemide-induced saline intake and conversely sodium appetite induction on morphine-induced locomotion. In an initial experiment rats were pretreated with morphine (10 mg/kg, s.c.) or vehicle for 5 days. The rats were then sodium or sham depleted and 24 h later given a sodium appetite test. Sodium depleted rats pretreated with morphine increased saline intake compared to depleted rats initially pretreated with vehicle. In a second experiment rats that were previously depleted and repleted of sodium as compared to sham depleted animals showed enhanced locomotor activity in an open field test when challenged with morphine (1 mg/kg, s.c.). These studies demonstrate that the behavioral responses induced by sodium deficiency and morphine treatment cross-sensitize with one another and suggest that common neural substrates underlie the sensitization of behaviors associated with states induced by morphine and sodium appetite.

  5. Cross-contamination with tamoxifen induces transgene expression in non-exposed inducible transgenic mice.

    PubMed

    Brake, Rachael L; Simmons, Paul J; Begley, C Glenn

    2004-12-30

    Inducible transgenic mouse models that impose a constraint on both temporal and spatial expression of a given transgene are invaluable. These animals facilitate experiments that can address the role of a specific cell or group of cells within an animal or in a particular window of time. A common approach to achieve inducibility involves the site-specific recombinase 'Cre', which is linked to a modified version of one of various steroid hormone-binding domains. Thus, the expression of Cre is regulated such that a functional nuclear transgene product can only be generated with the addition of an exogenous ligand. However, critical requirements of this system are that the nuclear localization of the transgene product be tightly regulated, that the dosage of the inducing agent remains consistent among experimental animals and that the transgene cassette cannot express in the absence of the inducing agent. We used the Cre ER(T2) cassette, which is regulated by the addition of the estrogen antagonist tamoxifen to determine whether cross-contamination of tamoxifen between animals housed together can be a significant source of spurious results. We found that cross-contamination of exogenous tamoxifen does occur. It occurred in all animals tested. We suggest that the mechanism of contamination is through exposure to tamoxifen in the general environment and/or to coprophagous behavior. These results have important implications for the interpretation and design of experiments that use 'inducible' transgenic animals.

  6. Behavioral cross-sensitization between DOCA-induced sodium appetite and cocaine-induced locomotor behavior

    PubMed Central

    Acerbo, Martin J.; Johnson, Alan Kim

    2011-01-01

    Behavioral sensitization involves increases in the magnitude of a response to a stimulus after repeated exposures to the same response initiator. Administration of psychomotor stimulants and the induction of appetitive motivational states associated with natural reinforcers like sugar and salt are among experimental manipulations producing behavioral sensitization. In rats, repeated administration of the mineralocorticoid agonist deoxycorticosterone acetate (DOCA) initially induces incremental increases in daily hypertonic saline consumption (i.e., sensitization of sodium appetite) in spite of the retention of sodium. The present studies investigated whether sodium appetite sensitization induced by DOCA shares mechanisms similar to those of psychomotor stimulant-induced sensitization, and whether there is evidence for reciprocal cross-sensitization. In Experiments 1 and 3, rats received control or cocaine treatments to induce locomotor sensitization. A week later DOCA (or vehicle) was administered to generate a sodium appetite. Animals pretreated with cocaine showed a greater sodium appetite. In Experiment 2, the order of the putative sensitizing treatments was reversed. Rats first received either a series of DOCA or vehicle treatments either with or without access to saline and were later tested for sensitization of the locomotor response to cocaine. Animals pretreated with DOCA without access to saline showed greater locomotor responses to cocaine than animals receiving vehicle treatments. Together these experiments indicate that treatments generating a sustained salt appetite and producing cocaine-induced psychomotor responses show reciprocal behavioral cross-sensitization. The underlying mechanisms accounting for this relationship may be the fact that psychostimulants and an unresolved craving for sodium can act as potent stressors. PMID:21352848

  7. Behavioral cross-sensitization between DOCA-induced sodium appetite and cocaine-induced locomotor behavior.

    PubMed

    Acerbo, Martin J; Johnson, Alan Kim

    2011-05-01

    Behavioral sensitization involves increases in the magnitude of a response to a stimulus after repeated exposures to the same response initiator. Administration of psychomotor stimulants and the induction of appetitive motivational states associated with natural reinforcers like sugar and salt are among experimental manipulations producing behavioral sensitization. In rats, repeated administration of the mineralocorticoid agonist deoxycorticosterone acetate (DOCA) initially induces incremental increases in daily hypertonic saline consumption (i.e., sensitization of sodium appetite) in spite of the retention of sodium. The present studies investigated whether sodium appetite sensitization induced by DOCA shares mechanisms similar to those of psychomotor stimulant-induced sensitization, and whether there is evidence for reciprocal cross-sensitization. In Experiments 1 and 3, rats received control or cocaine treatments to induce locomotor sensitization. A week later DOCA (or vehicle) was administered to generate a sodium appetite. Animals pretreated with cocaine showed a greater sodium appetite. In Experiment 2, the order of the putative sensitizing treatments was reversed. Rats first received either a series of DOCA or vehicle treatments either with or without access to saline and were later tested for sensitization of the locomotor response to cocaine. Animals pretreated with DOCA without access to saline showed greater locomotor responses to cocaine than animals receiving vehicle treatments. Together these experiments indicate that treatments generating a sustained salt appetite and producing cocaine-induced psychomotor responses show reciprocal behavioral cross-sensitization. The underlying mechanisms accounting for this relationship may be the fact that psychostimulants and an unresolved craving for sodium can act as potent stressors.

  8. Electron induced inelastic and ionization cross section for plasma modeling

    NASA Astrophysics Data System (ADS)

    Verma, Pankaj; Mahato, Dibyendu; Kaur, Jaspreet; Antony, Bobby

    2016-09-01

    The present paper reports electron impact total inelastic and ionization cross section for silicon, germanium, and tin tetrahalides at energies varying from ionization threshold of the target to 5000 eV. These cross section data over a wide energy domain are very essential to understand the physico-chemical processes involved in various environments such as plasma modeling, semiconductor etching, atmospheric sciences, biological sciences, and radiation physics. However, the cross section data on the above mentioned molecules are scarce. In the present article, we report the computation of total inelastic cross section using spherical complex optical potential formalism and the estimation of ionization cross section through a semi-empirical method. The present ionization cross section result obtained for SiCl4 shows excellent agreement with previous measurements, while other molecules have not yet been investigated experimentally. Present results show more consistent behaviour than previous theoretical estimates. Besides cross sections, we have also studied the correlation of maximum ionization cross section with the square root of the ratio of polarizability to ionization potential for the molecules with known polarizabilities. A linear relation is observed between these quantities. This correlation is used to obtain approximate polarizability volumes for SiBr4, SiI4, GeCl4, GeBr4, and GeI4 molecules.

  9. HPV16/18 L1 VLP Vaccine Induces Cross-Neutralizing Antibodies that May Mediate Cross-Protection

    PubMed Central

    Kemp, Troy J.; Hildesheim, Allan; Safaeian, Mahboobeh; Dauner, Joseph G.; Pan, Yuanji; Porras, Carolina; Schiller, John T.; Lowy, Douglas R.; Herrero, Rolando; Pinto, Ligia A.

    2011-01-01

    Human papillomavirus (HPV) L1 VLP-based vaccines are protective against HPV vaccine-related types; however, the correlates of protection have not been defined. We observed that vaccination with Cervarix™ induced cross-neutralizing antibodies for HPV types for which evidence of vaccine efficacy has been demonstrated (HPV31/45) but not for other types (HPV52/58). In addition, HPV31/45 cross-neutralizing titers showed a significant increase with number of doses (HPV31, p<0.001; HPV45, p<0.001) and correlated with HPV16/18 neutralizing titers, respectively. These findings raise the possibility that cross-neutralizing antibodies are effectors of cross-protection observed for the HPV16/18 vaccine. PMID:21241731

  10. Absolute photoneutron cross sections of Sm isotopes

    SciTech Connect

    Gheorghe, I.; Glodariu, T.; Utsunomiya, H.; Filipescu, D.; Nyhus, H.-T.; Renstrom, T.; Tesileanu, O.; Shima, T.; Takahisa, K.; Miyamoto, S.

    2015-02-24

    Photoneutron cross sections for seven samarium isotopes, {sup 144}Sm, {sup 147}Sm, {sup 148}Sm, {sup 149}Sm, {sup 150}Sm, {sup 152}Sm and {sup 154}Sm, have been investigated near neutron emission threshold using quasimonochromatic laser-Compton scattering γ-rays produced at the synchrotron radiation facility NewSUBARU. The results are important for nuclear astrophysics calculations and also for probing γ-ray strength functions in the vicinity of neutron threshold. Here we describe the neutron detection system and we discuss the related data analysis and the necessary method improvements for adapting the current experimental method to the working parameters of the future Gamma Beam System of Extreme Light Infrastructure - Nuclear Physics facility.

  11. A Study into the Collision-induced Dissociation (CID) Behavior of Cross-Linked Peptides.

    PubMed

    Giese, Sven H; Fischer, Lutz; Rappsilber, Juri

    2016-03-01

    Cross-linking/mass spectrometry resolves protein-protein interactions or protein folds by help of distance constraints. Cross-linkers with specific properties such as isotope-labeled or collision-induced dissociation (CID)-cleavable cross-linkers are in frequent use to simplify the identification of cross-linked peptides. Here, we analyzed the mass spectrometric behavior of 910 unique cross-linked peptides in high-resolution MS1 and MS2 from published data and validate the observation by a ninefold larger set from currently unpublished data to explore if detailed understanding of their fragmentation behavior would allow computational delivery of information that otherwise would be obtained via isotope labels or CID cleavage of cross-linkers. Isotope-labeled cross-linkers reveal cross-linked and linear fragments in fragmentation spectra. We show that fragment mass and charge alone provide this information, alleviating the need for isotope-labeling for this purpose. Isotope-labeled cross-linkers also indicate cross-linker-containing, albeit not specifically cross-linked, peptides in MS1. We observed that acquisition can be guided to better than twofold enrich cross-linked peptides with minimal losses based on peptide mass and charge alone. By help of CID-cleavable cross-linkers, individual spectra with only linear fragments can be recorded for each peptide in a cross-link. We show that cross-linked fragments of ordinary cross-linked peptides can be linearized computationally and that a simplified subspectrum can be extracted that is enriched in information on one of the two linked peptides. This allows identifying candidates for this peptide in a simplified database search as we propose in a search strategy here. We conclude that the specific behavior of cross-linked peptides in mass spectrometers can be exploited to relax the requirements on cross-linkers.

  12. Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iriduim and Gold

    SciTech Connect

    Hoffman, R D; Dietrich, F S; Kelley, K; Escher, J; Bauer, R; Mustafa, M

    2008-02-26

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from osmium (Z = 76) to gold (Z = 79). Of particular interest are the cross sections on Ir and Au including reactions on isomeric targets.

  13. The Status of Cross Section Measurements for Neutron-induced Reactions Needed for Cosmic Ray Studies

    NASA Technical Reports Server (NTRS)

    Sisterson, J. M.

    2003-01-01

    Cosmic ray interactions with lunar rocks and meteorites produce small amounts of radionuclides and stable isotopes. Advances in Accelerator Mass Spectrometry (AMS) allow production rates to be measured routinely in well-documented lunar rocks and meteorites. These measurements are analyzed using theoretical models to learn about the object itself and the history of the cosmic rays that fell on it. Good cross section measurements are essential input to the theoretical calculations. Most primary cosmic ray particles are protons so reliable cross sections for proton-induced reactions are essential. A cross section is deemed accurate if measurements made by different experimenters using different techniques result in consistent values. Most cross sections for proton induced reactions are now well measured. However, good cross section measurements for neutron-induced reactions are still needed. These cross sections are required to fully account for all galactic cosmic ray interactions at depth in an extraterrestrial object. When primary galactic cosmic ray (GCR) particles interact with an object many secondary neutrons are produced, which also initiate spallation reactions. Thus, the total GCR contribution to the overall cosmogenic nuclide archive has to include the contribution from the secondary neutron interactions. Few relevant cross section measurements have been reported for neutron-induced reactions at neutron energies greater than approximately 20 MeV. The status of the cross section measurements using quasi-monoenergetic neutron energies at iThemba LABS, South Africa and white neutron beams at Los Alamos Neutron Science Center (LANSCE), Los Alamos are reported here.

  14. The Status of Cross Section Measurements for Neutron-induced Reactions Needed for Cosmic Ray Studies

    NASA Technical Reports Server (NTRS)

    Sisterson, J. M.

    2003-01-01

    Cosmic ray interactions with lunar rocks and meteorites produce small amounts of radionuclides and stable isotopes. Advances in Accelerator Mass Spectrometry (AMS) allow production rates to be measured routinely in well-documented lunar rocks and meteorites. These measurements are analyzed using theoretical models to learn about the object itself and the history of the cosmic rays that fell on it. Good cross section measurements are essential input to the theoretical calculations. Most primary cosmic ray particles are protons so reliable cross sections for proton-induced reactions are essential. A cross section is deemed accurate if measurements made by different experimenters using different techniques result in consistent values. Most cross sections for proton induced reactions are now well measured. However, good cross section measurements for neutron-induced reactions are still needed. These cross sections are required to fully account for all galactic cosmic ray interactions at depth in an extraterrestrial object. When primary galactic cosmic ray (GCR) particles interact with an object many secondary neutrons are produced, which also initiate spallation reactions. Thus, the total GCR contribution to the overall cosmogenic nuclide archive has to include the contribution from the secondary neutron interactions. Few relevant cross section measurements have been reported for neutron-induced reactions at neutron energies greater than approximately 20 MeV. The status of the cross section measurements using quasi-monoenergetic neutron energies at iThemba LABS, South Africa and white neutron beams at Los Alamos Neutron Science Center (LANSCE), Los Alamos are reported here.

  15. Ion induced fragmentation cross-sections of DNA constituents

    NASA Astrophysics Data System (ADS)

    Rudek, Benedikt; Arndt, Alexander; Bennett, Daniel; Wang, Mingjie; Rabus, Hans

    2015-10-01

    Proton collision with chemical analogs for the base, the sugar and the phosphor residue of the DNA, namely pyrimidine, tetrahydrofuran and trimethyl phosphate, respectively, has been investigated. The impact energies ranged from 300 keV up to 16 MeV. For the first time, relative fragmentation cross-sections for proton impact are reported for tetrahydrofuran and trimethyl phosphate; previously reported cross sections for pyrimidine are extended for energies beyond 2500 keV. Ionization of tetrahydrofuran leads to a ring break in about 80% of all events, trimethyl phosphate predominantly fragments by bond cleavage to one of the three methyl-groups and for pyrimidine the parent ion has the highest abundance. Such comparison supports earlier findings that the sugar is the weak spot for strand breaks.

  16. Bepotastine-induced urticaria, cross-reactive with other antihistamines

    PubMed Central

    Kang, Ju Wan

    2016-01-01

    Second-generation antihistamines are widely prescribed for the control of symptoms of allergic inflammation such as itchy hives, coryza, and itchy eyes. In rare circumstances, these drugs might provoke allergic inflammation. Hypersensitivity to bepotastine besilate, a second-generation antihistamine has never been reported. A 17-year-old schoolgirl, whose paroxysmal itchy hives had been controlled with bepotastine, experienced aggravation of the hives. An oral provocation test confirmed her hypersensitivity to bepotastine and cross-reactivity to levocetirizine. She showed no reaction to chlorpheniramine, ketotifen, or olopatadine among the 13 antihistamines tested. While searching for an antihistamine to control her itchy hives, we found that she also exhibited cross-reactivity to various antihistamines with different chemical structures from that of bepotastine, which is not predicted according to the chemical classification of antihistamines. We report a case of hypersensitivity to bepotastine besilate in a patient with chronic spontaneous urticaria. PMID:27803886

  17. α scattering and α -induced reaction cross sections of 64Zn at low energies

    NASA Astrophysics Data System (ADS)

    Ornelas, A.; Mohr, P.; Gyürky, Gy.; Elekes, Z.; Fülöp, Zs.; Halász, Z.; Kiss, G. G.; Somorjai, E.; Szücs, T.; Takács, M. P.; Galaviz, D.; Güray, R. T.; Korkulu, Z.; Özkan, N.; Yalçın, C.

    2016-11-01

    Background: α -nucleus potentials play an essential role for the calculation of α -induced reaction cross sections at low energies in the statistical model. Uncertainties of these calculations are related to ambiguities in the adjustment of the potential parameters to experimental elastic scattering angular distributions and to the energy dependence of the effective α -nucleus potentials. Purpose: The present work studies the total reaction cross section σreac of α -induced reactions at low energies which can be determined from the elastic scattering angular distribution or from the sum over the cross sections of all open nonelastic channels. Method: Elastic and inelastic 64Zn(α ,α )64Zn angular distributions were measured at two energies around the Coulomb barrier, at 12.1 and 16.1 MeV. Reaction cross sections of the (α ,γ ) , (α ,n ) , and (α ,p ) reactions were measured at the same energies using the activation technique. The contributions of missing nonelastic channels were estimated from statistical model calculations. Results: The total reaction cross sections from elastic scattering and from the sum of the cross sections over all open nonelastic channels agree well within the uncertainties. This finding confirms the consistency of the experimental data. At the higher energy of 16.1 MeV, the predicted significant contribution of compound-inelastic scattering to the total reaction cross section is confirmed experimentally. As a by-product it is found that most recent global α -nucleus potentials are able to describe the reaction cross sections for 64Zn around the Coulomb barrier. Conclusions: Total reaction cross sections of α -induced reactions can be well determined from elastic scattering angular distributions. The present study proves experimentally that the total cross section from elastic scattering is identical to the sum of nonelastic reaction cross sections. Thus, the statistical model can reliably be used to distribute the total reaction

  18. Methylglyoxal-induced DNA-protein cross-links and cytotoxicity in Chinese hamster ovary cells.

    PubMed

    Brambilla, G; Sciabà, L; Faggin, P; Finollo, R; Bassi, A M; Ferro, M; Marinari, U M

    1985-05-01

    The technique of alkaline elution was applied to study the capacity of methylglyoxal to induce DNA damage and repair in Chinese hamster ovary cells. DNA cross-linking was observed after a 90-min exposure to a subtoxic dose (1.5 mM), and the cross-links were fully repaired by 24 h. The cross-linking appeared to be DNA-protein in nature, since proteinase treatment removed the effect. When the same cells were exposed to methylglyoxal in the presence of a rat liver metabolic system, both cytotoxicity and cross-linking frequency were significantly reduced.

  19. Stability of sublethal acid stress adaptaion and induced cross protection against lauric arginate in Listeria monocytogenes

    USDA-ARS?s Scientific Manuscript database

    The stability of acid stress adaptation in Listeria monocytogenes and its induced cross protection effect against GRAS (generally recognized as safe) antimicrobial compounds has never been investigated before. In the present study, the acid stress adaptation in L. monocytogenes was initially induced...

  20. Ciprofloxacin-induced immune-mediated thrombocytopenia: No cross-reactivity with gemifloxacin.

    PubMed

    Sim, D W; Yu, J E; Jeong, J; Koh, Y-I

    2017-08-08

    Fluoroquinolone-induced immune-mediated thrombocytopenia is uncommon, and no reports of cross-reactivity among fluoroquinolones exist. Here, we describe a case of ciprofloxacin-induced immune thrombocytopenia with no cross-reactivity with gemifloxacin. A 77-year-old woman showed profound thrombocytopenia immediately after two ciprofloxacin injections for pneumonia. Platelet counts recovered rapidly after ciprofloxacin discontinuation. She had experienced thrombocytopenia after ciprofloxacin administration 4 years earlier, which was assumed to be ciprofloxacin-induced immune-related. Interestingly, no thrombocytopenia occurred following the subsequent exposure to another fluoroquinolone, gemifloxacin. No cross-reactivity occurred between ciprofloxacin and gemifloxacin in this fluoroquinolone-induced immune thrombocytopenia case. © 2017 John Wiley & Sons Ltd.

  1. Rimonabant attenuates sensitization, cross-sensitization and cross-reinstatement of place preference induced by nicotine and ethanol.

    PubMed

    Biała, Grażyna; Budzyńska, Barbara

    2010-01-01

    The present study focused on the evaluation of behavioral sensitization, cross-sensitization, and cross-reinstatement processes induced by nicotine and ethanol in rodents. First, we showed that nicotine (0.175 mg/kg, base, intraperitoneally, ip) produced a conditioned place preference in rats. When the nicotine place preference was extinguished, nicotine-experienced animals were challenged with nicotine (0.175 mg/kg, ip) or ethanol (0.5 g/kg, ip), which reinstated a preference for the compartment previously paired with nicotine. In the second series of experiments, we demonstrated that after 9 days of nicotine administration (0.175 mg/kg, subcutaneously, sc) every other day and following its 7-day withdrawal, challenge doses of nicotine (0.175 mg/kg, sc) and ethanol (2 g/kg, ip) induced locomotor sensitization in mice. Finally, when we examined the influence of rimonabant (0.5, 1 and 2 mg/kg, ip), we found that this cannabinoid CB₁ receptor antagonist attenuated reinstatement effect of ethanol priming as well as nicotine sensitization and locomotor cross-sensitization between nicotine and ethanol. Our results indicate that similar endocannabinoid-dependent mechanisms re involved in the locomotor stimulant and reinforcing effects of nicotine and ethanol in rodents, and as such these data may provide further evidence for the use of cannabinoid CB₁ receptor antagonists in treatment of tobacco addiction with or without concomitant ethanol dependence.

  2. Comprehensive Amm242 neutron-induced reaction cross sections and resonance parameters

    NASA Astrophysics Data System (ADS)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Wimer, N.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; Ullmann, J. L.

    2017-06-01

    The 242Am metastable isomer's neutron-induced destruction mechanisms were studied at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array with a compact parallel-plate avalanche counter. New Amm242 neutron-capture cross sections were determined from 100 meV to 10 keV, and the absolute scale was set with respect to a concurrent measurement of the well-known Amm242 neutron-induced-fission cross section. The new fission cross section spans an energy range from 100 meV to 1 MeV and was normalized to the ENDF/B-VII.1 evaluated cross section to set the absolute scale. Our Amm242(n ,f ) cross section agrees well with the cross section of Browne et al. [Phys. Rev. C 29, 2188 (1984)], 10.1103/PhysRevC.29.2188 over this large energy interval. The new neutron-capture cross section measurement complements and agrees well with our recent results reported below 1 eV in Buckner et al. [Phys. Rev. C 95, 024610 (2017)], 10.1103/PhysRevC.95.024610. This new work comprises the most comprehensive study of Amm242(n ,γ ) above thermal energy. Neutron-induced resonance energies and parameters were deduced with the sammy R -matrix code for incident neutron energies up to 45 eV, and the new average Γγ is 13 % higher than the evaluated average γ width.

  3. Thermally induced stresses in cross-ply composite tubes

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Cooper, D. E.; Tompkins, S. S.

    1986-01-01

    An approximate solution for determining stresses in cross-ply composite tubes subjected to a circumferential temperature gradient is presented. The solution is based on the principle of complementary virtual work (PCVW) in conjunction with a Ritz approximation on the stress field and accounts for the temperature dependence of material properties. The PCVW method is compared with a planar elasticity solution using temperature-independent material properties and a Navier approach. The net effect of including temperature-dependent material properties is that the peak absolute values of the stresses are reduced. The dependence of the stresses on the circumferential location is also reduced in comparison with the case of temperature-independent properties.

  4. Vortex-crossing-induced timing jitter of superconducting nanowire single-photon detectors

    NASA Astrophysics Data System (ADS)

    Wu, Hao; Gu, Chao; Cheng, Yuhao; Hu, Xiaolong

    2017-08-01

    We investigate the timing properties of single-photon-triggered vortex (or anti-vortex) crossing in a current-biased superconducting nanowire and find that the time delays caused in the vortex-crossing process vary with the transverse positions on the nanowire where the photons are absorbed. The position-dependent time delays indicate that the vortex-crossing process induces timing jitter of a superconducting nanowire single-photon detector (SNSPD). The magnitude of this timing jitter further depends on various parameters, including the polarization of the incident photon, the bias current, and the width of the nanowire. This vortex-crossing-induced timing jitter might represent the lower bound of the timing jitter of the SNSPD and fundamentally limit its time-resolving capability.

  5. Saponin-based adjuvants induce cross-presentation in dendritic cells by intracellular lipid body formation

    PubMed Central

    den Brok, Martijn H.; Büll, Christian; Wassink, Melissa; de Graaf, Annemarie M.; Wagenaars, Jori A.; Minderman, Marthe; Thakur, Mayank; Amigorena, Sebastian; Rijke, Eric O.; Schrier, Carla C.; Adema, Gosse J.

    2016-01-01

    Saponin-based adjuvants (SBAs) are being used in animal and human (cancer) vaccines, as they induce protective cellular immunity. Their adjuvant potency is a factor of inflammasome activation and enhanced antigen cross-presentation by dendritic cells (DCs), but how antigen cross-presentation is induced is not clear. Here we show that SBAs uniquely induce intracellular lipid bodies (LBs) in the CD11b+ DC subset in vitro and in vivo. Using genetic and pharmacological interference in models for vaccination and in situ tumour ablation, we demonstrate that LB induction is causally related to the saponin-dependent increase in cross-presentation and T-cell activation. These findings link adjuvant activity to LB formation, aid the application of SBAs as a cancer vaccine component, and will stimulate development of new adjuvants enhancing T-cell-mediated immunity. PMID:27819292

  6. Cross flow induced vibrations in staggered arrays of cylindrical structures

    SciTech Connect

    Marn, J.

    1991-12-31

    Flow induced vibrations cause by instability is the subject of this investigation. The bulk of the work performed is theoretical in nature, the comparison with some of existing experimental data is given for each of four models described. First model encompasses the effects of prescribed motion on the cylinder. Such circumstances occur in the case of vortex shedding initiated instability. The reduced velocity within the cylinder array is low and there is no coupling between the adjacent cylinders. Second model assumes certain form of vibration and corresponding behavior of the perturbed velocity field in temporal and one of spatial coordinates thus transforming partial differential equations into ordinary differential equations and takes into account the motion of the neighboring cylinder. This corresponds to fluid elastic controlled instabilities. The resulting equations are solved analytically. The model is used for better understanding of the equations of cylinder motion as well as for quick estimates of threshold of instability. Third model relaxes an assumption about the form of vibration in spatial direction and uses the vorticity formulation of equation of fluid motion to account for fluid-solid interaction. This model analysis is of two phase (air-water mixture) flow. The void fraction distribution is found to be the single most decisive factor to determine the onset of instability for such a domain. In conclusion, two distinct mechanism were found to be responsible for flow induced vibration caused instabilities, (1) outside source controlled periodic excitation (such as vortex shedding) -- described by the first model and (2) fluid elastic forces -- described by second, third and fourth models. For the values of reduced velocity below 0.7 first model is proposed, for the values above 0.7, the rest.

  7. Neutron-induced fission-cross-section measurements and calculations of selected transplutonic isotopes

    SciTech Connect

    White, R.M.; Browne, J.C.

    1982-08-27

    The neutron-induced fission cross sections of /sup 242m/Am and /sup 245/Cm have been measured over an energy range of 10/sup -4/ eV to approx. 20 MeV in a series of experiments at three facilities during the past several years. The combined results of these measurements, in which only sub-milligram quantities of enriched isotopes were used, yield cross sections with uncertainties of approximately 5% below 10 MeV relative to the /sup 235/U standard cross section used to normalize the data. We summarize the resonance analysis of the /sup 242m/Am(n,f) cross section in the eV region. Hauser-Feshbach statistical calculations of the detailed fission cross sections of /sup 235/U and /sup 245/Cm have been carried out over the energy region from 0.1 to 5 MeV and these results are compared with our experimental data.

  8. MCNP6 updated proton-induced fission cross section calculations at intermediate energies

    NASA Astrophysics Data System (ADS)

    Kerby, Leslie; Mashnik, Stepan; Mulvaney, John

    2017-09-01

    MCNP6 has been Validated and Verified against intermediate- and high-energy fission cross-section experimental data. Recent improvements contained in CEM03.03F and MCNP6-F to consider precompound emission of heavy clusters up to 28Mg has necessitated a re-calculation of fission cross sections. With our re-calculation, we find that CEM03.03F, which is used in MCNP6-F, predicts fission cross sections in good agreement with available experimental data for reactions induced by protons on both subactinide and actinide nuclei at incident energies from several tens of MeV to several GeV.

  9. Cross-protection induced by Japanese encephalitis vaccines against different genotypes of Dengue viruses in mice

    PubMed Central

    Li, Jieqiong; Gao, Na; Fan, Dongying; Chen, Hui; Sheng, Ziyang; Fu, Shihong; Liang, Guodong; An, Jing

    2016-01-01

    Dengue viruses (DENVs) and Japanese encephalitis virus (JEV) are closely related mosquito-borne flaviviruses that cause very high global disease burdens. Although cross-reactivity and cross-protection within flaviviruses have been demonstrated, the effect of JEV vaccination on susceptibility to DENV infection has not been well elucidated. In this study, we found that vaccination with the JEV inactivated vaccine (INV) and live attenuated vaccine (LAV) could induce cross-immune responses and cross-protection against DENV1-4 in mice. Despite the theoretical risk of immune enhancement, no increased mortality was observed in our mouse model. Additionally, low but consistently detectable cross-neutralizing antibodies against DENV2 and DENV3 were also observed in the sera of JEV vaccine-immunized human donors. The results suggested that both JEV-LAV and JEV-INV could elicit strong cross-immunity and protection against DENVs, indicating that inoculation with JEV vaccines may influence the distribution of DENVs in co-circulated areas and that the cross-protection induced by JEV vaccines against DENVs might provide important information in terms of DENV prevention. PMID:26818736

  10. Cross-protection induced by Japanese encephalitis vaccines against different genotypes of Dengue viruses in mice.

    PubMed

    Li, Jieqiong; Gao, Na; Fan, Dongying; Chen, Hui; Sheng, Ziyang; Fu, Shihong; Liang, Guodong; An, Jing

    2016-01-28

    Dengue viruses (DENVs) and Japanese encephalitis virus (JEV) are closely related mosquito-borne flaviviruses that cause very high global disease burdens. Although cross-reactivity and cross-protection within flaviviruses have been demonstrated, the effect of JEV vaccination on susceptibility to DENV infection has not been well elucidated. In this study, we found that vaccination with the JEV inactivated vaccine (INV) and live attenuated vaccine (LAV) could induce cross-immune responses and cross-protection against DENV1-4 in mice. Despite the theoretical risk of immune enhancement, no increased mortality was observed in our mouse model. Additionally, low but consistently detectable cross-neutralizing antibodies against DENV2 and DENV3 were also observed in the sera of JEV vaccine-immunized human donors. The results suggested that both JEV-LAV and JEV-INV could elicit strong cross-immunity and protection against DENVs, indicating that inoculation with JEV vaccines may influence the distribution of DENVs in co-circulated areas and that the cross-protection induced by JEV vaccines against DENVs might provide important information in terms of DENV prevention.

  11. The Acetic Acid Tolerance Response induces cross-protection to salt stress in Salmonella typhimurium.

    PubMed

    Greenacre, E J; Brocklehurst, T F

    2006-10-15

    Salmonella typhimurium induces an Acid Tolerance Response (ATR) upon exposure to mildly acidic conditions in order to protect itself against severe acid shock. This response can also induce cross-protection to other stresses such as heat and salt. We investigated whether both the acetic acid induced and lactic acid induced ATR in S. typhimurium provided cross-protection to a salt stress at 20 degrees C. Acid-adapted cells were challenged with both a sodium chloride (NaCl) and potassium chloride (KCl) shock and their ability to survive ascertained. Acetic acid adaptation provided cells with protection against both NaCl and KCl stress. However, lactic acid adaptation did not protect against either osmotic stressor and rendered cells hypersensitive to NaCl. These results have implications for the food industry where hurdle technology means multiple sub-lethal stresses such as mild pH and low salt are commonly used in the preservation of products.

  12. Riboflavin/UVA Collagen Cross-Linking-Induced Changes in Normal and Keratoconus Corneal Stroma

    PubMed Central

    Hayes, Sally; Boote, Craig; Kamma-Lorger, Christina S.; Rajan, Madhavan S.; Harris, Jonathan; Dooley, Erin; Hawksworth, Nicholas; Hiller, Jennifer; Terill, Nick J.; Hafezi, Farhad; Brahma, Arun K.; Quantock, Andrew J.; Meek, Keith M.

    2011-01-01

    Purpose To determine the effect of Ultraviolet-A collagen cross-linking with hypo-osmolar and iso-osmolar riboflavin solutions on stromal collagen ultrastructure in normal and keratoconus ex vivo human corneas. Methods Using small-angle X-ray scattering, measurements of collagen D-periodicity, fibril diameter and interfibrillar spacing were made at 1 mm intervals across six normal post-mortem corneas (two above physiological hydration (swollen) and four below (unswollen)) and two post-transplant keratoconus corneal buttons (one swollen; one unswollen), before and after hypo-osmolar cross-linking. The same parameters were measured in three other unswollen normal corneas before and after iso-osmolar cross-linking and in three pairs of swollen normal corneas, in which only the left was cross-linked (with iso-osmolar riboflavin). Results Hypo-osmolar cross-linking resulted in an increase in corneal hydration in all corneas. In the keratoconus corneas and unswollen normal corneas, this was accompanied by an increase in collagen interfibrillar spacing (p<0.001); an increase in fibril diameter was also seen in two out of four unswollen normal corneas and one unswollen keratoconus cornea (p<0.001). Iso-osmolar cross-linking resulted in a decrease in tissue hydration in the swollen normal corneas only. Although there was no consistent treatment-induced change in hydration in the unswollen normal samples, iso-osmolar cross-linking of these corneas did result in a compaction of collagen fibrils and a reduced fibril diameter (p<0.001); these changes were not seen in the swollen normal corneas. Collagen D-periodicity was not affected by either treatment. Conclusion The observed structural changes following Ultraviolet-A cross-linking with hypo-osmolar or iso-osmolar riboflavin solutions are more likely a consequence of treatment-induced changes in tissue hydration rather than cross-linking. PMID:21850225

  13. Isotopic dependence of the cross section for the induced fission of heavy nuclei

    SciTech Connect

    Bolgova, O. N.; Adamian, G. G.; Antonenko, N. V.; Zubov, A. S.; Ivanova, S. P.; Scheid, W.

    2009-06-15

    The cross sections for the induced fission of {sup 211-223}Ra, {sup 203-211}Rn, and {sup 221-231}Th nuclei undergoing peripheral collisions with {sup 208}Pb nuclei are calculated on the basis of the statistical model. The role of the N = 126 neutron shell is studied. The level density in excited nuclei is determined within the Fermi gas model and a model that takes into account the collective enhancement of the level density. The inclusion of a particle-hole excitation in addition to a collective Coulomb excitation makes it possible to obtain a satisfactory description of experimental cross sections for the fission of radium isotopes. The calculated ratios of the cross sections for the induced fission of {sup 236}U ({sup 237}U) and {sup 238}U ({sup 239}U) nuclei agree with experimental data.

  14. Cross sections and barriers for nuclear fission induced by high-energy nucleons

    SciTech Connect

    Grudzevich, O. T.; Yavshits, S. G.

    2013-03-15

    The cross sections for the fission of {sup 232}Th, {sup 235,238}U, {sup 237}Np, and {sup 239}Pu target nuclei that was induced by 20- to 1000-MeV neutrons and protons were calculated. The respective calculations were based on the multiconfiguration-fission (MCFx) model, which was used to describe three basic stages of the interaction of high-energy nucleons with nuclei: direct processes (intranuclear cascade), equilibration of the emerging compound system, and the decay of the compound nucleus (statistical model). Fission barriers were calculated within the microscopic approach for isotopic chains formed by 15 to 20 nuclei of the required elements. The calculated fission cross sections were compared with available experimental data. It was shown that the input data set and the theoretical model used made it possible to predict satisfactorily cross section for nuclear fission induced by 20- to 1000-MeV nucleons.

  15. Cross-sensitization and cross-tolerance between exogenous cannabinoid antinociception and endocannabinoid-mediated stress-induced analgesia

    PubMed Central

    Suplita, Richard L.; Eisenstein, Sarah A.; Neely, Mark H.; Moise, Anna M.; Hohmann, Andrea G.

    2009-01-01

    Summary Footshock stress induces both endocannabinoid mobilization and antinociception. The present studies investigated behavioral plasticity in cannabinoid antinociceptive mechanisms following repeated activation using the tail-flick test. A secondary objective was to ascertain whether blockade of stress antinociception by the CB1 antagonist rimonabant could be attributed to changes in locomotor activity. The cannabinoid agonist WIN55,212-2 induced hypoactivity in the open field relative to vehicle-treated controls. By contrast, rimonabant, administered at a dose that virtually eliminated endocannabinoid-mediated stress antinociception, failed to alter locomotor behavior (i.e. time resting, ambulatory counts, distance traveled) in rats subjected to the same stressor. Rats exposed acutely to footshock were hypersensitive to the antinociceptive effects of WIN55,212-2 and Δ9-tetrahydrocannabinol (Δ9-THC). The converse was also true; acute Δ9-THC and WIN55,212-2 administration potentiated stress antinociception, suggesting a bidirectional sensitization between endocannabinoid-mediated stress antinociception and exogenous cannabinoid antinociception. Stress antinociception was also attenuated following chronic relative to acute treatment with WIN55,212-2 or Δ9-THC. Repeated exposure to footshock (3 min/day for 15 days), however, failed to attenuate antinociception induced by either footshock stress or WIN55,212-2. Our results demonstrate that endocannabinoid-mediated stress antinociception cannot be attributed to motor suppression. Our results further identify a functional plasticity of the cannabinoid system in response to repeated activation. The existence of cross-sensitization between endocannabinoid-mediated stress antinociception and exogenous cannabinoid antinociception suggests that these phenomena are mediated by a common mechanism. The observation of stress-induced hypersensitivity to effects of exogenous cannabinoids may have clinical implications for

  16. Microneedle delivery of trivalent influenza vaccine to the skin induces long-term cross-protection.

    PubMed

    Kim, Yeu-Chun; Lee, Su-Hwa; Choi, Won-Hyung; Choi, Hyo-Jick; Goo, Tae-Won; Lee, Ju-Hie; Quan, Fu-Shi

    2016-12-01

    A painless self-immunization method with effective and broad cross-protection is urgently needed to prevent infections against newly emerging influenza viruses. In this study, we investigated the cross-protection efficacy of trivalent influenza vaccine containing inactivated A/PR/8/34 (H1N1), A/Hong Kong/68 (H3N2) and B/Lee/40 after skin vaccination using microneedle patches coated with this vaccine. Microneedle vaccination of mice in the skin provided 100% protection against lethal challenges with heterologous pandemic strain influenza A/California/04/09, heterogeneous A/Philippines/2/82 and B/Victoria/287 viruses 8 months after boost immunization. Cross-reactive serum IgG antibody responses against heterologous influenza viruses A/California/04/09, A/Philippines/2/82 and B/Victoria/287 were induced at high levels. Hemagglutination inhibition titers were also maintained at high levels against these heterogeneous viruses. Microneedle vaccination induced substantial levels of cross-reactive IgG antibody responses in the lung and cellular immune responses, as well as cross-reactive antibody-secreting plasma cells in the spleen. Viral loads in the lung were significantly (p < 0.05) reduced. All mice survived after viral challenges. These results indicate that skin vaccination with trivalent vaccine using a microneedle array could provide protection against seasonal epidemic or new pandemic strain of influenza viruses.

  17. Cross-reactivity of hepatitis C virus specific vaccine-induced T cells at immunodominant epitopes.

    PubMed

    Kelly, Christabel; Swadling, Leo; Brown, Anthony; Capone, Stefania; Folgori, Antonella; Salio, Mariolina; Klenerman, Paul; Barnes, Eleanor

    2015-01-01

    Viral diversity is a challenge to the development of a hepatitis C virus (HCV) vaccine. Following vaccination of humans with adenoviral vectors, we determined the capacity of T cells to target common viral variants at immundominant epitopes ex vivo. We identified two major variants for epitopes NS3(1073) and NS3(1446), and multiple variants for epitope NS3(1406) that occurred in >5% of genotype 1 and 3 sequences at a population level. Cross-reactivity of vaccine-induced T cells was determined using variant peptides in IFN-γ ELISPOT assays. Vaccine-induced T cells targeted approximately 90% of NS3(1073) genotype 1 sequences and 50% of NS3(1446) genotype 1 and 3 sequences. For NS3(1406), 62% of subtype-1b sequences were targeted. Next, we assessed whether an in vitro priming system, using dendritic cells and T cells from healthy donors, could identify a variant of NS3(1406) that was maximally cross-reactive. In vitro priming assays showed that of those tested the NS3(1406) vaccine variant was the most immunogenic. T cells primed with genotype 1 variants from subtype 1a or 1b were broadly cross-reactive with other variants from the same subtype. We conclude that immunization with candidate HCV adenoviral vaccines generates cross-reactive T cells at immunodominant epitopes. The degree of cross-reactivity varies between epitopes and may be HCV-subtype specific.

  18. Induced tolerance from a sublethal insecticide leads to cross-tolerance to other insecticides.

    PubMed

    Hua, Jessica; Jones, Devin K; Relyea, Rick A

    2014-04-01

    As global pesticide use increases, the ability to rapidly respond to pesticides by increasing tolerance has important implications for the persistence of nontarget organisms. A recent study of larval amphibians discovered that increased tolerance can be induced by an early exposure to low concentrations of a pesticide. Since natural systems are often exposed to a variety of pesticides that vary in mode of action, we need to know whether the induction of increased tolerance to one pesticide confers increased tolerance to other pesticides. Using larval wood frogs (Lithobates sylvaticus), we investigated whether induction of increased tolerance to the insecticide carbaryl (AChE-inhibitor) can induce increased tolerance to other insecticides that have the same mode of action (chlorpyrifos, malathion) or a different mode of action (Na(+)channel-interfering insecticides; permethrin, cypermethrin). We found that embryonic exposure to sublethal concentrations of carbaryl induced higher tolerance to carbaryl and increased cross-tolerance to malathion and cypermethrin but not to chlorpyrifos or permethrin. In one case, the embryonic exposure to carbaryl induced tolerance in a nonlinear pattern (hormesis). These results demonstrate that that the newly discovered phenomenon of induced tolerance also provides induced cross-tolerance that is not restricted to pesticides with the same mode of action.

  19. Characteristic plateau in the L1 -subshell ionization cross section of Ag induced by proton collisions

    NASA Astrophysics Data System (ADS)

    Kavčič, M.; Šmit, Ž.

    2009-12-01

    A characteristic dependence of the proton-induced 2s subshell ionization cross section generated by the nodal structure of the 2s wave function was probed via high-resolution measurements of the Lβ3 (L1-M3) and Lβ6 (L3-N1) x-ray lines of Ag. The intensity ratio of the measured lines depends strongly on the proton energy exhibiting a pronounced maximum around 0.4 MeV. The experimental intensities are critically compared to the theoretically predicted values. The latter were obtained using the ionization cross sections calculated within the semiclassical approximation employing hydrogenlike and Dirac-Fock electron wave functions.

  20. Optical switching of cross intensity correlation in cavity electromagnetically induced transparency

    NASA Astrophysics Data System (ADS)

    Rao, Shi; Hu, Xiangming; Xu, Jun; Li, Lingchao

    2017-03-01

    We present optical switching of cross intensity correlation in the context of cavity electromagnetically induced transparency configuration. For symmetrical parameters, the cross intensity correlation switches from negative to positive as the atom–pump detunings change symmetrically from one case to the other. In terms of the dressed atomic states and the Bogoliubov modes we analyze the atom–photon interaction mechanism for the switching behavior, and present a numerical verification. As a by-product, we show noise squeezing of the sum or difference intensity in a limited region of parameters.

  1. Measurement of the Am242m neutron-induced reaction cross sections

    DOE PAGES

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; ...

    2017-02-17

    The neutron-induced reaction cross sections of 242mAm were measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. A new neutron-capture cross section was determined, and the absolute scale was set according to a concurrent measurement of the well-known 242mAm(n,f) cross section. The (n,γ) cross section was measured from thermal energy to an incident energy of 1 eV at which point the data quality was limited by the reaction yield in the laboratory. Our new 242mAm fission cross section was normalized to ENDF/B-VII.1 tomore » set the absolute scale, and it agreed well with the (n,f) cross section from thermal energy to 1 keV. Lastly, the average absolute capture-to-fission ratio was determined from thermal energy to En = 0.1 eV, and it was found to be 26(4)% as opposed to the ratio of 19% from the ENDF/B-VII.1 evaluation.« less

  2. Measurement of the Amm242 neutron-induced reaction cross sections

    NASA Astrophysics Data System (ADS)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Wimer, N.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; Ullmann, J. L.; Dance Collaboration

    2017-02-01

    The neutron-induced reaction cross sections of Amm242 were measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. A new neutron-capture cross section was determined, and the absolute scale was set according to a concurrent measurement of the well-known Amm242(n ,f ) cross section. The (n ,γ ) cross section was measured from thermal energy to an incident energy of 1 eV at which point the data quality was limited by the reaction yield in the laboratory. Our new Amm242 fission cross section was normalized to ENDF/B-VII.1 to set the absolute scale, and it agreed well with the (n ,f ) cross section reported by Browne et al. (1984) from thermal energy to 1 keV. The average absolute capture-to-fission ratio was determined from thermal energy to En=0.1 eV, and it was found to be 26(4)% as opposed to the ratio of 19 % from the ENDF/B-VII.1 evaluation.

  3. Calculated differential and double differential cross section of DT neutron induced reactions on natural chromium (Cr)

    NASA Astrophysics Data System (ADS)

    Rajput, Mayank; Vala, Sudhirsinh; Srinivasan, R.; Abhangi, M.; Subhash, P. V.; Pandey, B.; Rao, C. V. S.; Bora, D.

    2017-07-01

    Chromium is an important alloying element of stainless steel (SS) and SS is the main constituent of structural material proposed for fusion reactors. Energy and double differential cross section data will be required to estimate nuclear responses in the materials used in fusion reactors. There are no experimental data of energy and double differential cross section, available for neutron induced reactions on natural chromium at 14 MeV neutron energy. In this study, energy and double differential cross section data of (n,p) and (n,α) reactions for all the stable isotopes of chromium have been estimated, using appropriate nuclear models in TALYS code. The cross section data of stable isotopes are later converted into the energy and double differential cross section data of natural Cr using the isotopic abundance. The contribution from compound, pre-equilibrium and direct nuclear reaction to total reaction have also been calculated for 52,50Cr(n,p) and 52Cr(n,α). The calculation of energy differential cross section shows that most of emitted protons and alpha particles are of 3 and 8 MeV respectively. The calculated data is compared with the data from EXFOR data library and is found to be in good agreement.

  4. Nanosecond laser-induced periodic surface structuring of cross-linked azo-polymer films

    NASA Astrophysics Data System (ADS)

    Berta, Marco; Biver, Émeric; Maria, Sébastien; Phan, Trang N. T.; D'Aleo, Anthony; Delaporte, Philippe; Fages, Frederic; Gigmes, Didier

    2013-10-01

    In this work we discuss the response to laser ablation of a poly(4-vinylbenzyl azide-random-methyl methacrylate) (p((S-N3)-r-MMA)) random copolymer. This material is cross-linkable thermally and upon exposure to UV light, and on cross-linked films the irradiation with a 248 nm ns KrF laser induces the formation of laser induced periodical surface structure (LIPSS). The LIPSS morphology is dependent on the amount of 4-vinylbenzyl azide (S-N3) groups in the pristine copolymer. We propose a crosslinking mechanism based on the scission of azide with formation of azo groups and we discuss the possible relationship between this chemical modifications and the formation of ripples on the bottom of laser ablation cavities.

  5. Reducing Uncertainties in Neutron-Induced Fission Cross Sections Using a Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Manning, Brett; Niffte Collaboration

    2015-10-01

    Neutron-induced fission cross sections for actinides have long been of great interest for nuclear energy and stockpile stewardship. Traditionally, measurements were performed using fission chambers which provided limited information about the detected fission events. For the case of 239Pu(n,f), sensitivity studies have shown a need for more precise measurements. Recently the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) has developed the fission Time Projection Chamber (fissionTPC) to measure fission cross sections to better than 1% uncertainty by providing 3D tracking of fission fragments. The fissionTPC collected data to calculate the 239Pu(n,f) cross section at the Weapons Neutron Research facility at the Los Alamos Neutron Science Center during the 2014 run cycle. Preliminary analysis has been focused on studying particle identification and target and beam non-uniformities to reduce the uncertainty on the cross section. Additionally, the collaboration is investigating other systematic errors that could not be well studied with a traditional fission chamber. LA-UR-15-24906.

  6. Reducing Uncertainties in Neutron Induced Fission Cross Sections via a Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Magee, Joshua; Niffte Collaboration

    2016-09-01

    Neutron induced fission cross sections of actinides are of great interest in nuclear energy and stockpile stewardship. Traditionally, measurements of these cross sections have been made with fission chambers, which provide limited information on the actual fragments, and ultimately result in uncertainties on the order of several percent. The Neutron Induced Fission Fragment Tracking Experiment collaboration (NIFFTE) designed and built a fission Time Project Chamber (fission TPC), which provides additional information on these processes, through 3-dimensional tracking, improved particle identification, and in-situ profiles of target and beam non-uniformities. Ultimately, this should provide sub-percent measurements of (n,f) cross-sections. During the 2015 run cycle, measurements of several actinides were performed at the Los Alamos Neutron Science Center (LANSCE) Weapons Neutron Research (WNR) facility. An overview of the fission TPC will be given, as well as the current progress towards a sub-percent measurement of the 239Pu/235U (n,f) cross-section ratio. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  7. Calculations of Proton Emission Cross Sections in Deuteron Induced Reactions of Some Fusion Structural Materials

    NASA Astrophysics Data System (ADS)

    Yiğit, M.; Tel, E.; Tanır, G.

    2013-06-01

    The growing demands for energy consumption have led to the increase of the research and development activities on new energy sources. Fusion energy has the highest potential to become a very safe, clean and abundant energy source for the future. To get energy from fusion are needed for development of fusion reactor technology. Particularly, the design and development of international facilities as International Thermonuclear Experimental Reactor and International Fusion Material Irradiation Facility requires for the cross-section data of deuteron induced reactions. Moreover, the selection of fusion structural materials are an indispensable component for this technology. Therefore, the cross-section data of deuteron induced reactions on fusion structural materials are of great importance for development of fusion reactor technology. In this study, reaction model calculations of the cross sections of deuteron induced reactions on structural fusion materials such as 27Al, 59Co, 55Mn, 50Cr, 54Cr, 64Ni, 109Ag, 184W and 186W have been carried out for incident energies up to 50 MeV. In these calculations, the pre-equilibrium and equilibrium effects for ( d, p) stripping reactions have been investigated. The pre-equilibrium calculations involve the new evaluated the geometry dependent hybrid model and hybrid model. Equilibrium effects are calculated according to the Weisskopf-Ewing model. In the calculations the program code ALICE/ASH was used. The calculated results are discussed and compared with the experimental data taken from the literature.

  8. Cross-linked bromelain inhibits lipopolysaccharide-induced cytokine production involving cellular signaling suppression in rats.

    PubMed

    Hou, Rolis Chien-Wei; Chen, Yuh-Shuen; Huang, Jing-Rong; Jeng, Kee-Ching G

    2006-03-22

    Bromelain has been reported to have anti-inflammatory and immunomodulatory effects. It has been cross-linked with organic acids and polysaccharides by gamma irradiation. The cross-linked (CL)-bromelain preparation resisted an acidic environment of pH 3 for 2 h and preserved 80% of its enzyme activity. Pretreatment of rats with CL-bromelain intragastrically for 7 days significantly reduced serum cytokine production induced by injected i.p. with 2.5 mg/kg of lipopolysaccharide (LPS). Bromelain significantly reduced serum glutamate-oxalacetate transaminase induced by LPS. The anti-inflammatory effect of CL-bromelain was correlated with reduced LPS-induced NF-kappaB activity and cyclooxygenase 2 (COX-2) mRNA expression in rat livers. In addition, CL-bromelain dose-dependently inhibited LPS-induced COX-2 mRNA and prostaglandin E2 (PGE2) in BV-2 microglial cells. CL-Bromelain also suppressed the LPS-activated extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK). In conclusion, the anti-inflammatory effects of the CL-bromelain preparation in vivo and in vitro suggest its therapeutic potentials.

  9. Riboflavin-UVA-induced corneal collagen cross-linking in pediatric patients.

    PubMed

    Caporossi, Aldo; Mazzotta, Cosimo; Baiocchi, Stefano; Caporossi, Tomaso; Denaro, Rosario; Balestrazzi, Angelo

    2012-03-01

    Evaluation of stability and functional response after riboflavin-UVA–induced cross-linking in a population of patients younger than 18 years with progressive keratoconus after 36 months of follow-up. Prospective nonrandomized phase II open trial conducted at the Department of Ophthalmology, Siena University, Italy. The "Siena CXL Pediatrics" trial involved 152 patients aged 18 years or younger (10–18 years) with clinical and instrumental evidence of keratoconus progression. The population was divided into 2 groups according to corneal thickness (>450 and <450 μm) at the time of enrollment. The riboflavin-UVA–induced corneal cross-linking was performed in all patients according to the standard epi-off protocol. Parameters recorded preoperatively and postoperatively were as follows: uncorrected visual acuity, best spectacle–corrected visual acuity, corneal topography and surface aberrometry (CSO Eye Top topographer; Florence, Italy), optical pachometry (Visante OCT; Zeiss Meditec, Jena, Germany), and HRT II confocal microscopy (Rostock Cornea Module, Heidelberg, Germany). Functional data at 36 months showed an increase of +0.18 and +0.16 Snellen lines for uncorrected visual acuity and best spectacle-corrected visual acuity, respectively, in the thicker group (corneal thickness >450 μm) and +0.14 and +0.15 Snellen lines, respectively, in the thinner group (corneal thickness <450 μm). Patients in the latter group already showed a better and faster functional recovery than the thicker group at 3-month follow-up. Topographic results showed statistically significant improvement in K readings and asymmetry index values. Coma reduction was also statistically significant. The study demonstrated significant and rapid functional improvement in pediatric patients younger than 18 years with progressive keratoconus, undergoing riboflavin-UVA–induced cross-linking. In pediatric age, a good functional response and keratoconus stability was obtained after corneal cross

  10. Acoustic radiation force for noninvasive evaluation of corneal biomechanical changes induced by cross-linking therapy.

    PubMed

    Urs, Raksha; Lloyd, Harriet O; Silverman, Ronald H

    2014-08-01

    To noninvasively measure changes in corneal biomechanical properties induced by ultraviolet-activated riboflavin cross-linking therapy using acoustic radiation force (ARF). Cross-linking was performed on the right eyes of 6 rabbits, with the left eyes serving as controls. Acoustic radiation force was used to assess corneal stiffness before treatment and weekly for 4 weeks after treatment. Acoustic power levels were within US Food and Drug Administration guidelines for ophthalmic safety. Strain, determined from ARF-induced displacement of the front and back surfaces of the cornea, was fit to the Kelvin-Voigt model to determine the elastic modulus (E) and coefficient of viscosity (η). The stiffness factor, the ratio of E after treatment to E before treatment, was calculated for treated and control eyes. At the end of 4 weeks, ex vivo thermal shrinkage temperature analysis was performed for comparison with in vivo stiffness measurements. One-way analysis of variance and Student t tests were performed to test for differences in E, η, the stiffness factor, and corneal thickness. Biomechanical stiffening was immediately evident in cross-linking-treated corneas. At 4 weeks after treatment, treated corneas were 1.3 times stiffer and showed significant changes in E (P= .006) and η (P= .007), with no significant effect in controls. Corneal thickness increased immediately after treatment but did not differ significantly from the pretreatment value at 4 weeks. Our findings demonstrate a statistically significant increase in stiffness in cross-linking-treated rabbit corneas based on in vivo axial stress/strain measurements obtained using ARF. The capacity to noninvasively monitor corneal stiffness offers the potential for clinical monitoring of cross-linking therapy. © 2014 by the American Institute of Ultrasound in Medicine.

  11. Acoustic Radiation Force for Noninvasive Evaluation of Corneal Biomechanical Changes Induced by Cross-linking Therapy

    PubMed Central

    Urs, Raksha; Lloyd, Harriet O.; Silverman, Ronald H.

    2015-01-01

    Objectives To noninvasively measure changes in corneal biomechanical properties induced by ultraviolet-activated riboflavin cross-linking therapy using acoustic radiation force (ARF). Methods Cross-linking was performed on the right eyes of 6 rabbits, with the left eyes serving as controls. Acoustic radiation force was used to assess corneal stiffness before treatment and weekly for 4 weeks after treatment. Acoustic power levels were within US Food and Drug Administration guidelines for ophthalmic safety. Strain, determined from ARF-induced displacement of the front and back surfaces of the cornea, was fit to the Kelvin-Voigt model to determine the elastic modulus (E) and coefficient of viscosity (η). The stiffness factor, the ratio of E after treatment to E before treatment, was calculated for treated and control eyes. At the end of 4 weeks, ex vivo thermal shrinkage temperature analysis was performed for comparison with in vivo stiffness measurements. One-way analysis of variance and Student t tests were performed to test for differences in E, η, the stiffness factor, and corneal thickness. Results Biomechanical stiffening was immediately evident in cross-linking–treated corneas. At 4 weeks after treatment, treated corneas were 1.3 times stiffer and showed significant changes in E(P= .006) and η (P= .007), with no significant effect in controls. Corneal thickness increased immediately after treatment but did not differ significantly from the pretreatment value at 4 weeks. Conclusions Our findings demonstrate a statistically significant increase in stiffness in cross-linking–treated rabbit corneas based on in vivo axial stress/strain measurements obtained using ARF. The capacity to noninvasively monitor corneal stiffness offers the potential for clinical monitoring of cross-linking therapy. PMID:25063407

  12. Heavy ion induced mutations in mammalian cells: Cross sections and molecular analysis

    NASA Technical Reports Server (NTRS)

    Stoll, U.; Schmidt, P.; Schneider, E.; Kiefer, J.

    1994-01-01

    Our investigations of heavy ion-induced mutations in mammalian cells, which had been begun a few years ago, were systematically continued. For the first time, it was possible to cover a large LET range with a few kinds of ions. To do this, both UNILAC and SIS were used to yield comparable data for a large energy range. This is a necessary condition for a comprehensive description of the influence of such ion parameters as energy and LET. In these experiments, the induced resistance against the poison 6-thioguanin (6-TG), which is linked to the HPRT locus on the genome, is being used as mutation system. In addition to the mutation-induction cross-section measurements, the molecular changes of the DNA are being investigated by means of Multiplex PCR ('Polymerase Chain Reaction') gene amplification. From these experiments we expect further elucidation of the mutation-inducing mechanisms composing the biological action of heavy-ion radiation.

  13. Dissecting the Mechanisms of Tissue Transglutaminase-induced Cross-linking of α-Synuclein

    PubMed Central

    Schmid, Adrien W.; Chiappe, Diego; Pignat, Vérène; Grimminger, Valerie; Hang, Ivan; Moniatte, Marc; Lashuel, Hilal A.

    2009-01-01

    Tissue transglutaminase (tTG) has been implicated in the pathogenesis of Parkinson disease (PD). However, exactly how tTG modulates the structural and functional properties of α-synuclein (α-syn) and contributes to the pathogenesis of PD remains unknown. Using site-directed mutagenesis combined with detailed biophysical and mass spectrometry analyses, we sought to identify the exact residues involved in tTG-catalyzed cross-linking of wild-type α-syn and α-syn mutants associated with PD. To better understand the structural consequences of each cross-linking reaction, we determined the effect of tTG-catalyzed cross-linking on the oligomerization, fibrillization, and membrane binding of α-syn in vitro. Our findings show that tTG-catalyzed cross-linking of monomeric α-syn involves multiple cross-links (specifically 2-3). We subjected tTG-catalyzed cross-linked monomeric α-syn composed of either wild-type or Gln → Asn mutants to sequential proteolysis by multiple enzymes and peptide mapping by mass spectrometry. Using this approach, we identified the glutamine and lysine residues involved in tTG-catalyzed intramolecular cross-linking of α-syn. These studies demonstrate for the first time that Gln79 and Gln109 serve as the primary tTG reactive sites. Mutating both residues to asparagine abolishes tTG-catalyzed cross-linking of α-syn and tTG-induced inhibition of α-syn fibrillization in vitro. To further elucidate the sequence and structural basis underlying these effects, we identified the lysine residues that form isopeptide bonds with Gln79 and Gln109. This study provides mechanistic insight into the sequence and structural basis of the inhibitory effects of tTG on α-syn fibrillogenesis in vivo, and it sheds light on the potential role of tTG cross-linking on modulating the physiological and pathogenic properties of α-syn. PMID:19164286

  14. A measurement of neutrino induced quasi-elastic cross section in NOMAD

    NASA Astrophysics Data System (ADS)

    Kim, Jae

    NOMAD (Neutrino Oscillation MAgnetic Detector) is a short baseline neutrino experiment at CERN (the European Laboratory for Particle physics) West Area Neutrino Facility (WANF) with a neutrino beam provided by the super proton synchrotron (SPS) accelerator [98]. In this dissertation, we present a measurement of the muon-neutrino induced quasi-elastic (QEL), nu mu + n → mu- + p, cross-section off an isoscalar target in the NOMAD detector. The incident neutrino energy in NOMAD experiment spans from 2.5 to 300 GeV. The measurement of the cross-section is conducted in a two-track topology where both a muon and a proton are fully reconstructed, and a one-track topology where only a muon is reconstructed. The QEL cross-section as a function of the incoming neutrino energy is consistent for the two different topologies, and within errors, constant as a function of the neutrino energy. We determine the energy-averaged cross-section, sigma = 0:908 +/- 0:012 (stat) +/-0:035 (syst) 10-38cm2, where the first is the averaged energy-dependent error (statistical error is dominant one), and the second is the energy-independent, or overall, error. From the shape-comparisons of kinematics of QEL events, the axial mass parameter is determined. It is in good agreement with the result from the measurement of QEL cross-section. Using the chi2 of the shapes of four independent kinematic variables between data and MC, we determine MA = 1:03 +/- 0:05 GeV. The cross-section and the axial mass presented in this thesis have the best precision to date.

  15. Two-photon induced collagen cross-linking in bioartificial cardiac tissue

    NASA Astrophysics Data System (ADS)

    Kuetemeyer, Kai; Kensah, George; Heidrich, Marko; Meyer, Heiko; Martin, Ulrich; Gruh, Ina; Heisterkamp, Alexander

    2011-08-01

    Cardiac tissue engineering is a promising strategy for regenerative therapies to overcome the shortage of donor organs for transplantation. Besides contractile function, the stiffness of tissue engineered constructs is crucial to generate transplantable tissue surrogates with sufficient mechanical stability to withstand the high pressure present in the heart. Although several collagen cross-linking techniques have proven to be efficient in stabilizing biomaterials, they cannot be applied to cardiac tissue engineering, as cell death occurs in the treated area. Here, we present a novel method using femtosecond (fs) laser pulses to increase the stiffness of collagen-based tissue constructs without impairing cell viability. Raster scanning of the fs laser beam over riboflavin-treated tissue induced collagen cross-linking by two-photon photosensitized singlet oxygen production. One day post-irradiation, stress-strain measurements revealed increased tissue stiffness by around 40% being dependent on the fibroblast content in the tissue. At the same time, cells remained viable and fully functional as demonstrated by fluorescence imaging of cardiomyocyte mitochondrial activity and preservation of active contraction force. Our results indicate that two-photon induced collagen cross-linking has great potential for studying and improving artificially engineered tissue for regenerative therapies.

  16. Behavioural differentiation induced by environmental variation when crossing a toxic zone in an amoeba

    NASA Astrophysics Data System (ADS)

    Kunita, Itsuki; Ueda, Kei-Ichi; Akita, Dai; Kuroda, Shigeru; Nakagaki, Toshiyuki

    2017-09-01

    Organisms choose from among various courses of action in response to a wide variety of environmental conditions and the mechanism by which various behaviours are induced is an open question. Interesting behaviour was recently reported: that a unicellular organism of slime mold Physarum polycephalum known as an amoeba had multiple responses (crossing, returning, etc) when the amoeba encounters a zone with toxic levels of quinine, even under carefully controlled conditions. We here examined this elegant example in more detail to obtain insight into behavioural differentiation. We found that the statistical distribution of passage times across a quinine zone switch from unimodal to bimodal (with peaks corresponding to fast crossing and no crossing) when a periodic light stimulation to modulate a biorhythm in amoeba is applied homogeneously across the space, even under the same level of chemical stimuli. Based on a mathematical model for cell movement in amoeba, we successfully reproduced the stimulation-induced differentiation, which was observed experimentally. These dynamics may be explained by a saddle structure around a canard solution. Our results imply that the differentiation of behavioural types in amoeba is modified step-by-step via the compounding of stimulation inputs. The complex behaviour like the differentiation in amoeba may provide a basis for understanding the mechanism of behaviour selection in higher animals from an ethological perspective.

  17. Measurement of muon neutrino and antineutrino induced single neutral pion production cross sections

    SciTech Connect

    Anderson, Colin E.

    2011-05-01

    flux-averaged, total cross sections for NC 1π0 production on CH2 to be (4.76 ± 0.05stat ± 0.76sys) x 10-40 cm2/nucleon at ν> = 808 MeV for neutrino induced production and (1.48 ± 0.05stat ± 0.23sys) x 10-40 cm2/nucleon at ν> = 664 MeV for antineutrino induced production.

  18. Effect of pre-equilibrium spin distribution on neutron-induced reaction cross sections

    SciTech Connect

    Dashdorj, D.; Mitchell, G. E.; Becker, J. A.; Wu, C. Y.; Chadwick, M. B.; Devlin, M.; Fotiades, N.; Kawano, T.; Nelson, R. O.; Garrett, P. E.; Kunieda, S.

    2008-04-17

    Cross section measurements were made of prompt gamma-ray production as a function of neutron energy using the germanium array for neutron induced excitations (GEANIE) at LANSCE. Measuring the prompt reaction gamma rays as a function of incident neutron energy provides more precise understanding of the spins populated by the pre-equilibrium reaction. The effect of the spin distribution in pre-equilibrium reactions has been investigated using the GNASH reaction code. Widely used classical theories such as the exciton model usually assume that the spin distribution of the pre-equilibrium reaction is the same as the spin distribution of the compound nucleus reaction mechanism. In the present approach, the pre-equilibrium reaction spin distribution was calculated using the quantum mechanical theory of Feshbach, Kerman, and Koonin (FKK). This pre-equilibrium spin distribution was incorporated into the GNASH code and the gamma-ray production cross sections were calculated and compared with experimental data. Spin distributions peak at lower spin when calculated with the FKK formulation than with the Compound Nuclear theory. The measured partial gamma-ray cross sections reflect this spin difference. Realistic treatment of the spin distribution improves the accuracy of calculations of gamma-ray production cross sections.

  19. Mechlorethamine-Induced DNA-Protein Cross-Linking in Human Fibrosarcoma (HT1080) Cells

    PubMed Central

    Michaelson-Richie, Erin D.; Ming, Xun; Codreanu, Simona G.; Loeber, Rachel L.; Liebler, Daniel C.; Campbell, Colin; Tretyakova, Natalia Y.

    2011-01-01

    Antitumor nitrogen mustards, such as bis(2-chloroethyl)methylamine (mechlorethamine), are useful chemotherapeutic agents with a long history of clinical application. The antitumor effects of nitrogen mustards are attributed to their ability to induce DNA-DNA and DNA-protein cross-links (DPCs) that block DNA replication. In the present work, a mass spectrometry based methodology was employed to characterize in vivo DNA-protein cross-linking following treatment of human fibrosarcoma (HT1080) cells with cytotoxic concentrations of mechlorethamine. A combination of mass spectrometry-based proteomics and immunological detection was used to identify 38 nuclear proteins which were covalently cross-linked to chromosomal DNA following treatment with mechlorethamine. Isotope dilution HPLC-ESI+-MS/MS analysis of total proteolytic digests revealed a concentration-dependent formation of N-[2-(S-cysteinyl)ethyl]-N-[2-(guan-7-yl)ethyl]methylamine (Cys-N7G-EMA) conjugates, indicating that mechlorethamine cross-links cysteine thiols within proteins to N-7 positions of guanine in DNA. PMID:21486066

  20. Mechlorethamine-induced DNA-protein cross-linking in human fibrosarcoma (HT1080) cells.

    PubMed

    Michaelson-Richie, Erin D; Ming, Xun; Codreanu, Simona G; Loeber, Rachel L; Liebler, Daniel C; Campbell, Colin; Tretyakova, Natalia Y

    2011-06-03

    Antitumor nitrogen mustards, such as bis(2-chloroethyl)methylamine (mechlorethamine), are useful chemotherapeutic agents with a long history of clinical application. The antitumor effects of nitrogen mustards are attributed to their ability to induce DNA-DNA and DNA-protein cross-links (DPCs) that block DNA replication. In the present work, a mass spectrometry-based methodology was employed to characterize in vivo DNA-protein cross-linking following treatment of human fibrosarcoma (HT1080) cells with cytotoxic concentrations of mechlorethamine. A combination of mass spectrometry-based proteomics and immunological detection was used to identify 38 nuclear proteins that were covalently cross-linked to chromosomal DNA following treatment with mechlorethamine. Isotope dilution HPLC-ESI(+)-MS/MS analysis of total proteolytic digests revealed a concentration-dependent formation of N-[2-(S-cysteinyl)ethyl]-N-[2-(guan-7-yl)ethyl]methylamine (Cys-N7G-EMA) conjugates, indicating that mechlorethamine cross-links cysteine thiols within proteins to N-7 positions of guanine in DNA.

  1. Neutron induced fission cross section measurements of 240Pu and 242Pu

    NASA Astrophysics Data System (ADS)

    Belloni, F.; Eykens, R.; Heyse, J.; Matei, C.; Moens, A.; Nolte, R.; Plompen, A. J. M.; Richter, S.; Sibbens, G.; Vanleeuw, D.; Wynants, R.

    2017-09-01

    Accurate neutron induced fission cross section of 240Pu and 242Pu are required in view of making nuclear technology safer and more efficient to meet the upcoming needs for the future generation of nuclear power plants (GEN-IV). The probability for a neutron to induce such reactions figures in the NEA Nuclear Data High Priority Request List [1]. A measurement campaign to determine neutron induced fission cross sections of 240Pu and 242Pu at 2.51 MeV and 14.83 MeV has been carried out at the 3.7 MV Van De Graaff linear accelerator at Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig. Two identical Frisch Grid fission chambers, housing back to back a 238U and a APu target (A = 240 or A = 242), were employed to detect the total fission yield. The targets were molecular plated on 0.25 mm aluminium foils kept at ground potential and the employed gas was P10. The neutron fluence was measured with the proton recoil telescope (T1), which is the German primary standard for neutron fluence measurements. The two measurements were related using a De Pangher long counter and the charge as monitors. The experimental results have an average uncertainty of 3-4% at 2.51 MeV and for 6-8% at 14.81 MeV and have been compared to the data available in literature.

  2. Principles of femtosecond X-ray/optical cross-correlation with X-ray induced transient optical reflectivity in solids

    NASA Astrophysics Data System (ADS)

    Eckert, S.; Beye, M.; Pietzsch, A.; Quevedo, W.; Hantschmann, M.; Ochmann, M.; Ross, M.; Minitti, M. P.; Turner, J. J.; Moeller, S. P.; Schlotter, W. F.; Dakovski, G. L.; Khalil, M.; Huse, N.; Föhlisch, A.

    2015-02-01

    The discovery of ultrafast X-ray induced optical reflectivity changes enabled the development of X-ray/optical cross correlation techniques at X-ray free electron lasers worldwide. We have now linked through experiment and theory the fundamental excitation and relaxation steps with the transient optical properties in finite solid samples. Therefore, we gain a thorough interpretation and an optimized detection scheme of X-ray induced changes to the refractive index and the X-ray/optical cross correlation response.

  3. Principles of femtosecond X-ray/optical cross-correlation with X-ray induced transient optical reflectivity in solids

    SciTech Connect

    Eckert, S. E-mail: martin.beye@helmholtz-berlin.de; Beye, M. E-mail: martin.beye@helmholtz-berlin.de; Pietzsch, A.; Quevedo, W.; Hantschmann, M.; Ochmann, M.; Huse, N.; Ross, M.; Khalil, M.; Minitti, M. P.; Turner, J. J.; Moeller, S. P.; Schlotter, W. F.; Dakovski, G. L.; Föhlisch, A.

    2015-02-09

    The discovery of ultrafast X-ray induced optical reflectivity changes enabled the development of X-ray/optical cross correlation techniques at X-ray free electron lasers worldwide. We have now linked through experiment and theory the fundamental excitation and relaxation steps with the transient optical properties in finite solid samples. Therefore, we gain a thorough interpretation and an optimized detection scheme of X-ray induced changes to the refractive index and the X-ray/optical cross correlation response.

  4. Neutron and Charged-Particle Induced Cross Sections for Radiochemistry in the Region of Bromine and Krypton

    SciTech Connect

    Hoffman, R; Dietrich, F; Bauer, R; Kelley, K; Mustafa, M

    2004-07-23

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron and proton induced nuclear reaction cross sections in the mass region of bromine and krypton (34 {le} Z {le} 37, 40 {le} N {le} 47).

  5. Neutron and Charged-Particle Induced Cross Sections for Radiochemistry in the Region of Samarium, Europium, and Gadolinium

    SciTech Connect

    Hoffman, R D; Kelley, K; Dietrich, F S; Bauer, R; Mustafa, M

    2004-11-30

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron and proton induced nuclear reaction cross sections in the mass region of samarium, europium and gadolinium (62 {le} Z {le} 64, 82 {le} N {le} 96).

  6. Fertilization and uniparental chromosome elimination during crosses with maize haploid inducers.

    PubMed

    Zhao, Xin; Xu, Xiaowei; Xie, Hongxia; Chen, Shaojiang; Jin, Weiwei

    2013-10-01

    Producing maternal haploids via a male inducer can greatly accelerate maize (Zea mays) breeding process. However, the mechanism underlying haploid formation remains unclear. In this study, we constructed two inducer lines containing cytogenetic marker B chromosome or alien centromeric histone H3 variant-yellow fluorescent protein vector to investigate the mechanism. The two inducer lines as the pollinators were crossed with a hybrid ZhengDan958. B chromosomes were detected in F1 haploids at a low frequency, which was direct evidence to support the occurrence of selective chromosome elimination during haploid formation. We found that most of the inducer chromosomes were eliminated in haploid embryonic cells during the first week after pollination. The gradual elimination of chromosomes was also detected in the endosperm of defective kernels, although it occurred only in some endosperm cells as late as 15 d after pollination. We also performed a genome-wide identification of single nucleotide polymorphism markers in the inducers, noninducer inbred lines, and 42 derived haploids using a 50K single nucleotide polymorphism array. We found that an approximately 44-Mb heterozygous fragment from the male parent was detected in a single haploid, which further supported the occurrence of paternal introgression. Our results suggest that selective elimination of uniparental chromosomes leads to the formation of haploid and possible defective kernels in maize as well, which is accompanied with unusual paternal introgression in haploid cells.

  7. Effects of chebulic acid on advanced glycation endproducts-induced collagen cross-links.

    PubMed

    Lee, Ji-Young; Oh, Jun-Gu; Kim, Jin Sook; Lee, Kwang-Won

    2014-01-01

    Advanced glycation end-products (AGEs) have been implicated in the development of diabetic complications. We report the antiglycating activity of chebulic acid (CA), isolated from Terminalia chebula on breaking the cross-links of proteins induced by AGEs and inhibiting the formation of AGEs. Aminoguanidine (AG) reduced 50% of glycated bovine serum albumin (BSA) with glycolaldehyde (glycol-BSA)-induced cross-links of collagen at a concentration of 67.8 ± 2.5 mM, the level of CA required for exerting a similar antiglycating activity was 38.8 ± 0.5 µM. Also, the breaking activity on collagen cross-links induced by glycol-BSA was potent with CA (IC50=1.46 ± 0.05 mM), exhibiting 50-fold stronger breaking activity than with ALT-711, a well-known cross-link breaker (IC50=72.2 ± 2.4 mM). IC50 values of DPPH· scavenging activity for CA and ascorbic acid (AA) were 39.2 ± 4.9 and 19.0 ± 1.2 µg dry matter (DM) mL(-1), respectively, and ferric reducing and antioxidant power (FRAP) activities for CA and AA were 4.70 ± 0.06 and 11.4 ± 0.1 mmol/FeSO4·7H2O/g DM, respectively. The chelating activities of CA, AG and ALT711 on copper-catalyzed oxidation of AA were compared, and in increasing order, ALT-711 (IC50 of 1.92 ± 0.20 mM)cross-linking, the activity of which may be explained in large part by its chelating and antioxidant activities, suggesting that CA may constitute a promising antiglycating candidate in intervening AGE-mediated diabetic complications.

  8. Combinatorial electrostatic collision-induced dissociative chemical cross-linking reagents for probing protein surface topology.

    PubMed

    Liu, Fan; Goshe, Michael B

    2010-07-15

    To ascertain more information on protein domain orientation and complex structure associations using chemical cross-linking, we have developed a combination of electrostatic collision-induced dissociative cross-linking reagents that differentially react with protein surfaces which are effectively analyzed by liquid chromatography-tandem mass spectrometry using ion trap multistage collision-induced dissociation. Implementing our original design and methodology based on disuccinimidyl-succinamyl-aspartyl-proline (SuDP) (Soderblom, E. J.; Goshe, M. B. Anal. Chem 2006, 78, 8059-8068. Soderblom, E. J.; Bobay, B. G.; Cavanagh, J.; Goshe, M. B. Rapid Commun Mass Spectrom 2007, 21, 3395-3408.), disuccinimidyl-succinamyl-valyl-proline (SuVP) was synthesized. The SuDP and SuVP reagents are the same except for the valyl and aspartyl groups which provide a distinctive chemical feature to each reagent. When performing labeling reactions using various protein-to-cross-linker ratios at pH 7.5, the negatively charged SuDP and neutral SuVP were used to label bovine serum albumin and hemoglobin. After protein digestion, the resulting peptides were analyzed using four different ion trap LC/MS(3) acquisition methods incorporating multistage CID. The more polar BSA surface resulted in a number of unique interpeptide and intrapeptide cross-links for each reagent whereas the less polarized surface of hemoglobin produced similar results for both reagents. Based on the identification of dead-end products (i.e., a cross-link modification containing a hydrolyzed end) for each protein, the aminolysis reactivity of each modified lysyl side chain revealed a preference for reacting with each reagent according to its local electrostatic surface environment. Overall, combinatorial application of SuDP and SuVP chemical labeling produces a set of unique interpeptide, intrapeptide, and dead-end cross-linked products that provides protein structural information according to its electrostatic surface

  9. Dynamics of traffic flows on crossing roads induced by real-time information

    NASA Astrophysics Data System (ADS)

    Fukui, Minoru; Ishibashi, Yoshihiro; Nishinari, Katsuhiro

    2013-02-01

    Traffic flows on crossing roads with an information board installed at the intersection have been simulated by a cellular automaton model. In the model, drivers have to enter the road with a shorter trip-time indicated on the information board, by making a turn at the intersection if necessary. The movement of drivers induces various traffic states, which are classified into six phases as a function of the car density. The dynamics of the traffic is expressed as the return map in the density-flow space, and analyzed on the basis of the car configuration on the roads.

  10. Measurement of Neutrino Induced Exclusive Quasi-Elastic Cross Section in NOMAD

    NASA Astrophysics Data System (ADS)

    Kim, Jae

    2007-04-01

    The measurement of neutrino induced charged current Quasi-Elastic (QE) cross section using the NOMAD data will be presented. The signature of the νμ QE interaction is an outgoing -circ and a proton. I developed a likelihood probability density function to separate QE from background - two track resonance and deep inelastic scattering events. Data themselves were used to help constrain the background estimate. By kinematic comparison to the measured QE data, the axial mass was also measured. This preliminary result is among the most precise measurements of the QE process.

  11. SET-Induced Biaryl Cross-Coupling: An SRN1 Reaction

    PubMed Central

    2015-01-01

    The SET-induced biaryl cross-coupling reaction is established as the first example of a Grignard SRN1 reaction. The reaction is examined within the mechanistic framework of dissociative electron transfer in the presence of a Lewis acid. DFT calculations show that the reaction proceeds through a radical intermediate in the form of an Mg ion-radical cage, which eludes detection in trapping experiments by reacting quickly to form an MgPh2 radical anion intermediate. A new mechanism is proposed. PMID:24564385

  12. Experimental Study of the Cross Sections of {alpha}-Particle Induced Reactions on 209Bi

    SciTech Connect

    Hermanne, A.; Tarkanyi, F.; Takacs, S.; Szucs, Z.

    2005-05-24

    Alpha particle induced reactions for generation of 211At used in therapeutic nuclear medicine and possible contaminants were investigated with the stacked foil activation technique on natural bismuth targets up to E{alpha}=39 MeV. Excitation functions for the reactions 209Bi({alpha},2n)211At, 209Bi({alpha},3n)210At, 209Bi({alpha},x) 210Po obtained from direct alpha emission measurements and gamma spectra from decay products are compared with earlier literature values. Thick target yields have been deduced from the experimental cross sections.

  13. Experimental Study of the Cross Sections of α-Particle Induced Reactions on 209Bi

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Tárkányi, F.; Takács, S.; Szúcs, Z.

    2005-05-01

    Alpha particle induced reactions for generation of 211At used in therapeutic nuclear medicine and possible contaminants were investigated with the stacked foil activation technique on natural bismuth targets up to Eα=39 MeV. Excitation functions for the reactions 209Bi(α,2n)211At, 209Bi(α,3n)210At, 209Bi(α,x) 210Po obtained from direct alpha emission measurements and gamma spectra from decay products are compared with earlier literature values. Thick target yields have been deduced from the experimental cross sections.

  14. Cross-phase-modulation-induced instability in photonic-crystal fibers.

    PubMed

    Serebryannikov, E E; Konorov, S O; Ivanov, A A; Alfimov, M V; Scalora, M; Zheltikov, A M

    2005-08-01

    Cross-phase-modulation-induced instability is identified as a significant mechanism for efficient parametric four-wave-mixing frequency conversion in photonic-crystal fibers. Fundamental-wavelength femtosecond pulses of a Cr, forsterite laser are used in our experiments to transform the spectrum of copropagating second-harmonic pulses of the same laser in a photonic-crystal fiber. Efficient generation of sidebands shifted by more than 80 THz with respect to the central frequency of the second harmonic is observed in the output spectrum of the probe field.

  15. Cancer-associated Fibroblasts Induce a Collagen Cross-link Switch in Tumor Stroma

    PubMed Central

    Pankova, Daniela; Chen, Yulong; Terajima, Masahiko; Schliekelman, Mark J.; Baird, Brandi N.; Fahrenholtz, Monica; Sun, Li; Gill, Bartley J.; Vadakkan, Tegy J.; Kim, Min P.; Ahn, Young-Ho; Roybal, Jonathon D.; Liu, Xin; Parra Cuentas, Edwin Roger; Rodriguez, Jaime; Wistuba, Ignacio I.; Creighton, Chad J.; Gibbons, Don L.; Hicks, John M.; Dickinson, Mary E.; West, Jennifer L.; Grande-Allen, K. Jane; Hanash, Samir M.; Yamauchi, Mitsuo; Kurie, Jonathan M.

    2015-01-01

    Intratumoral collagen cross-links heighten stromal stiffness and stimulate tumor cell invasion, but it is unclear how collagen cross-linking is regulated in epithelial tumors. To address this question, we used KrasLA1 mice, which develop lung adenocarcinomas from somatic activation of a KrasG12D allele. The lung tumors in KrasLA1 mice were highly fibrotic and contained cancer-associated fibroblasts (CAFs) that produced collagen and generated stiffness in collagen gels. In xenograft tumors generated by injection of wild-type mice with lung adenocarcinoma cells alone or in combination with CAFs, the total concentration of collagen cross-links was the same in tumors generated with or without CAFs, but co-injected tumors had higher hydroxylysine aldehyde-derived collagen cross-links (HLCCs) and lower lysine-aldehyde-derived collagen cross-links (LCCs). Therefore, we postulated that an LCC-to-HLCC switch induced by CAFs promotes the migratory and invasive properties of lung adenocarcinoma cells. To test this hypothesis, we created co-culture models in which CAFs are positioned interstitially or peripherally in tumor cell aggregates, mimicking distinct spatial orientations of CAFs in human lung cancer. In both contexts, CAFs enhanced the invasive properties of tumor cells in 3-dimensional (3D) collagen gels. Tumor cell aggregates that attached to CAF networks on a Matrigel surface dissociated and migrated on the networks. Lysyl hydroxylase 2 (PLOD2/LH2), which drives HLCC formation, was expressed in CAFs, and LH2 depletion abrogated the ability of CAFs to promote tumor cell invasion and migration. PMID:26631572

  16. Evaporation residue cross-section measurements for 48Ti-induced reactions

    NASA Astrophysics Data System (ADS)

    Sharma, Priya; Behera, B. R.; Mahajan, Ruchi; Thakur, Meenu; Kaur, Gurpreet; Kapoor, Kushal; Rani, Kavita; Madhavan, N.; Nath, S.; Gehlot, J.; Dubey, R.; Mazumdar, I.; Patel, S. M.; Dhibar, M.; Hosamani, M. M.; Khushboo, Kumar, Neeraj; Shamlath, A.; Mohanto, G.; Pal, Santanu

    2017-09-01

    Background: A significant research effort is currently aimed at understanding the synthesis of heavy elements. For this purpose, heavy ion induced fusion reactions are used and various experimental observations have indicated the influence of shell and deformation effects in the compound nucleus (CN) formation. There is a need to understand these two effects. Purpose: To investigate the effect of proton shell closure and deformation through the comparison of evaporation residue (ER) cross sections for the systems involving heavy compound nuclei around the ZCN=82 region. Methods: A systematic study of ER cross-section measurements was carried out for the 48Ti+Nd,150142 , 144Sm systems in the energy range of 140 -205 MeV . The measurement has been performed using the gas-filled mode of the hybrid recoil mass analyzer present at the Inter University Accelerator Centre (IUAC), New Delhi. Theoretical calculations based on a statistical model were carried out incorporating an adjustable barrier scaling factor to fit the experimental ER cross section. Coupled-channel calculations were also performed using the ccfull code to obtain the spin distribution of the CN, which was used as an input in the calculations. Results: Experimental ER cross sections for 48Ti+Nd,150142 were found to be considerably smaller than the statistical model predictions whereas experimental and statistical model predictions for 48Ti+144Sm were of comparable magnitudes. Conclusion: Though comparison of experimental ER cross sections with statistical model predictions indicate considerable non-compound-nuclear processes for 48Ti+Nd,150142 reactions, no such evidence is found for the 48Ti+144Sm system. Further investigations are required to understand the difference in fusion probabilities of 48Ti+142Nd and 48Ti+144Sm systems.

  17. Cross-protection induced by Toxoplasma gondii virus-like particle vaccine upon intraperitoneal route challenge.

    PubMed

    Lee, Dong-Hun; Kim, Ah-Ra; Lee, Su-Hwa; Quan, Fu-Shi

    2016-12-01

    The inner membrane complex sub-compartment has a critical role in Toxoplasma gondii endodyogeny. In this study, we investigated the protection upon intraperitoneal route (IP) challenge induced by the virus-like particles (VLPs) vaccine containing Toxoplasma gondii IMC ISP (RH strain) (Type I). Intranasal immunization with the VLPs in mice elicited enhanced systemic and mucosal Toxoplasma gondii-specific IgG, IgG1, IgG2a and IgA antibody responses, and CD4+ and CD8+ responses. Immunized mice significantly reduced T. gondii cyst burden and size in brain, resulting in cross-protection upon T. gondii (ME49) (Type II) challenge infection. These results indicate that the IP route challenge infection induced by T. gondii IMC ISP VLPs might be a very good target for vaccination representing novel approach to reduce infection. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Diversion of HIV-1 Vaccine-induced Immunity by gp41-Microbiota Cross-reactive Antibodies

    PubMed Central

    Williams, Wilton B; Liao, Hua-Xin; Moody, M. Anthony; Kepler, Thomas B.; Alam, S Munir; Gao, Feng; Wiehe, Kevin; Trama, Ashley M.; Jones, Kathryn; Zhang, Ruijun; Song, Hongshuo; Marshall, Dawn J; Whitesides, John F; Sawatzki, Kaitlin; Hua, Axin; Liu, Pinghuang; Tay, Matthew Z; Seaton, Kelly; Shen, Xiaoying; Foulger, Andrew; Lloyd, Krissey E.; Parks, Robert; Pollara, Justin; Ferrari, Guido; Yu, Jae-Sung; Vandergrift, Nathan; Montefiori, David C.; Sobieszczyk, Magdalena E; Hammer, Scott; Karuna, Shelly; Gilbert, Peter; Grove, Doug; Grunenberg, Nicole; McElrath, Julie; Mascola, John R.; Koup, Richard A; Corey, Lawrence; Nabel, Gary J.; Morgan, Cecilia; Churchyard, Gavin; Maenza, Janine; Keefer, Michael; Graham, Barney S.; Baden, Lindsey R.; Tomaras, Georgia D.; Haynes, Barton F.

    2015-01-01

    A HIV-1 DNA prime-recombinant Adenovirus Type 5 (rAd5) boost vaccine failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells was to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies (mAbs) were non-neutralizing, and frequently polyreactive with host and environmental antigens including intestinal microbiota (IM). Next generation sequencing of an IGHV repertoire prior to vaccination revealed an Env-IM cross-reactive Ab that was clonally-related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy. PMID:26229114

  19. Carbodiimide induced cross-linking, ligand addition, and degradation in gelatin.

    PubMed

    Cammarata, Christopher R; Hughes, Mitchell E; Ofner, Clyde M

    2015-03-02

    The water-soluble carbodiimide, 1-ethyl-3-(3-(dimethylaminopropyl)-carbodiimide (EDC) is widely used in protein chemistry. We used EDC-induced gelatin cross-linking as a model for amide bond formation to resolve reaction ambiguities with common variables of buffers, gelatin concentration, and pH. Percentage changes in SEC high molecular weight peak areas were used to follow the reactions. Differences in reaction rate and extent were observed with four commonly used buffers, while differences in extent were observed for commonly used concentrations and pH. We also investigated an anhydride mechanism for aqueous EDC-induced amide bond formation that has received little attention since its proposal in 1995. Gelatin carboxyl groups had a synergistic role during the addition of hydrazine to corroborate the anhydride formation between carboxyl groups. EDC-induced degradation of gelatin was investigated using percentage changes in SEC low molecular weight peak areas. The degradation occurred in excess EDC at neutral to alkaline pH and was enhanced substantially when reacting amino groups were not available. A mechanism of EDC-induced gelatin degradation is proposed and designated the extended Khorana mechanism. This EDC side reaction has the potential to occur in peptides and proteins under similar conditions.

  20. AAV natural infection induces broad cross-neutralizing antibody responses to multiple AAV serotypes in chimpanzees.

    PubMed

    Calcedo, Roberto; Wilson, James M

    2016-06-01

    Cross-sectional studies of primates have revealed that natural neutralizing antibody (NAb) responses to adeno-associated viruses (AAV) span multiple serotypes. This differs from the phenotype of the NAb response to an AAV vector delivered to sero-negative nonhuman primates which is typically restricted to the administered AAV serotype. To better understand the mechanism by which natural AAV infections result in broad NAb responses, we conducted a longitudinal study spanning 10 years in which we evaluated serum-circulating AAV NAb levels in captive-housed chimpanzees. In a cohort of 25 chimpanzees we identified three distinct groups of animals: those which never sero-converted to AAV (naïve); those which were persistently seropositive (chronic); and those that seroconverted during the 10 year period (acute). For the chronic group we found a broad sero-response characterized by NAbs reacting to multiple AAV serotypes. A similar cross-neutralization pattern of NAbs was observed in the acute group. These data support our hypothesis that a single natural infection with AAV induces a broadly cross-reactive NAb response to multiple AAV serotypes.

  1. AAV Natural Infection Induces Broad Cross-Neutralizing Antibody Responses to Multiple AAV Serotypes in Chimpanzees.

    PubMed

    Calcedo, Roberto; Wilson, James M

    2016-06-01

    Cross-sectional studies of primates have revealed that natural neutralizing antibody (NAb) responses to adeno-associated viruses (AAV) span multiple serotypes. This differs from the phenotype of the NAb response to an AAV vector delivered to seronegative nonhuman primates that is typically restricted to the administered AAV serotype. To better understand the mechanism by which natural AAV infections result in broad NAb responses, we conducted a longitudinal study spanning 10 years in which we evaluated serum-circulating AAV NAb levels in captive-housed chimpanzees. In a cohort of 25 chimpanzees we identified 3 distinct groups of animals: those that never seroconverted to AAV (naïve), those that were persistently seropositive (chronic), and those that seroconverted during the 10-year period (acute). For the chronic group we found a broad seroresponse characterized by NAbs reacting to multiple AAV serotypes. A similar cross-neutralization pattern of NAbs was observed in the acute group. These data support our hypothesis that a single natural infection with AAV induces a broadly cross-reactive NAb response to multiple AAV serotypes.

  2. Bayesian Evaluation Including Covariance Matrices of Neutron-induced Reaction Cross Sections of {sup 181}Ta

    SciTech Connect

    Leeb, H. Schnabel, G.; Srdinko, Th.; Wildpaner, V.

    2015-01-15

    A new evaluation of neutron-induced reactions on {sup 181}Ta using a consistent procedure based on Bayesian statistics is presented. Starting point of the evaluation is the description of nuclear reactions via nuclear models implemented in TALYS 1.4. A retrieval of experimental data was performed and covariance matrices of the experiments were generated from an extensive study of the corresponding literature. All reaction channels required for a transport file up to 200 MeV have been considered and the covariance matrices of cross section uncertainties for the most important channels are determined. The evaluation has been performed in one step including all available experimental data. A comparison of the evaluated cross sections and spectra with experimental data and available evaluations is performed. In general the evaluated cross section reflect our best knowledge and give a fair description of the observables. However, there are few deviations from expectation which clearly indicate the impact of the prior and the need to account for model defects. Using the results of the evaluation a complete ENDF-file similarly to those of the TENDL library is generated.

  3. A case of levocetirizine-induced fixed drug eruption and cross-reaction with piperazine derivatives.

    PubMed

    Kim, Mi-Yeong; Jo, Eun-Jung; Chang, Yoon-Seok; Cho, Sang-Heon; Min, Kyung-Up; Kim, Sae-Hoon

    2013-10-01

    Fixed drug eruption is an uncommon adverse drug reaction caused by delayed cell-mediated hypersensitivity. Levocetirizine is an active (R)-enatiomer of cetirizine and there have been a few reports of fixed drug eruption related to these antihistamines. We experienced a case of levocetirizine-induced fixed drug eruption and cross-reaction with other piperazine derivatives confirmed by patch test. A 73-year-old female patient presented with recurrent generalized itching, cutaneous bullae formation, rash and multiple pigmentation at fixed sites after taking drugs for common cold. She took bepotastine besilate (Talion®) and levocetirizine (Xyzal®) as antihistamine. She took acetaminophen, pseudoephedrine 60 mg / triprolidine 2.5 mg (Actifed®), dihydrocodeinebitartrate 5 mg / di-methylephedrine hydrochloride 17.5 mg / chlorpheniramine maleate 1.5 mg / guaifenesin 50 mg (Codening®) and aluminium hydroxide 200 mg / magnesium carbonate 120 mg (Antad®) at the same time. Patch test was done with suspected drugs and the result was positive with levocetirizine. We additionally performed patch test for other antihistamines such as cetirizine, hydroxyzine, fexofenadine and loratadine. Piperazine derivatives (cetirizine and hydroxyzine) were positive, but piperidine derivatives (fexofenadine and loratadine) were negative to patch test. There was no adverse drug reaction when she was challenged with fexofenadine. We report a case of levocetirizine-induced fixed drug eruption confirmed by patch test. Cross-reactions were only observed in the piperazine derivatives and piperidine antihistamine was tolerant to the patient.

  4. A case of levocetirizine-induced fixed drug eruption and cross-reaction with piperazine derivatives

    PubMed Central

    Kim, Mi-Yeong; Jo, Eun-Jung; Chang, Yoon-Seok; Cho, Sang-Heon; Min, Kyung-Up

    2013-01-01

    Fixed drug eruption is an uncommon adverse drug reaction caused by delayed cell-mediated hypersensitivity. Levocetirizine is an active (R)-enatiomer of cetirizine and there have been a few reports of fixed drug eruption related to these antihistamines. We experienced a case of levocetirizine-induced fixed drug eruption and cross-reaction with other piperazine derivatives confirmed by patch test. A 73-year-old female patient presented with recurrent generalized itching, cutaneous bullae formation, rash and multiple pigmentation at fixed sites after taking drugs for common cold. She took bepotastine besilate (Talion®) and levocetirizine (Xyzal®) as antihistamine. She took acetaminophen, pseudoephedrine 60 mg / triprolidine 2.5 mg (Actifed®), dihydrocodeinebitartrate 5 mg / di-methylephedrine hydrochloride 17.5 mg / chlorpheniramine maleate 1.5 mg / guaifenesin 50 mg (Codening®) and aluminium hydroxide 200 mg / magnesium carbonate 120 mg (Antad®) at the same time. Patch test was done with suspected drugs and the result was positive with levocetirizine. We additionally performed patch test for other antihistamines such as cetirizine, hydroxyzine, fexofenadine and loratadine. Piperazine derivatives (cetirizine and hydroxyzine) were positive, but piperidine derivatives (fexofenadine and loratadine) were negative to patch test. There was no adverse drug reaction when she was challenged with fexofenadine. We report a case of levocetirizine-induced fixed drug eruption confirmed by patch test. Cross-reactions were only observed in the piperazine derivatives and piperidine antihistamine was tolerant to the patient. PMID:24260733

  5. Cross sections of proton- and neutron-induced reactions by the Liège intranuclear cascade model

    NASA Astrophysics Data System (ADS)

    Chen, Jian; Dong, Tiekuang; Ren, Zhongzhou

    2016-06-01

    The purpose of the paper is mainly to test the validity of the Liège intranuclear cascade (INCL) model in calculating the cross sections of proton-induced reactions for cosmogenic nuclei using the newly compiled database of proton cross sections. The model calculations of 3He display the rising tendency of cross sections with the increase of energy, in accordance with the experimental data. Meanwhile, the differences between the theoretical results and experimental data of production cross sections (10Be and 26Al) are generally within a factor of 3, meaning that the INCL model works quite well for the proton-induced reactions. Based on the good agreement, we predict the production cross sections of 26Al from reactions n + 27Al, n + 28Si, and n + 40Ca and those of 10Be from reactions n + 16O and n + 28Si. The results also show a good agreement with a posteriori excitation functions.

  6. Statistical model analysis of α -induced reaction cross sections of 64Zn at low energies

    NASA Astrophysics Data System (ADS)

    Mohr, P.; Gyürky, Gy.; Fülöp, Zs.

    2017-01-01

    Background: α -nucleus potentials play an essential role in the calculation of α -induced reaction cross sections at low energies in the statistical model. Uncertainties of these calculations are related to ambiguities in the adjustment of the potential parameters to experimental elastic scattering angular distributions (typically at higher energies) and to the energy dependence of the effective α -nucleus potentials. Purpose: The present work studies cross sections of α -induced reactions for 64Zn at low energies and their dependence on the chosen input parameters of the statistical model calculations. The new experimental data from the recent Atomki experiments allow for a χ2-based estimate of the uncertainties of calculated cross sections at very low energies. Method: Recently measured data for the (α ,γ ), (α ,n ), and (α ,p ) reactions on 64Zn are compared to calculations in the statistical model. A survey of the parameter space of the widely used computer code talys is given, and the properties of the obtained χ2 landscape are discussed. Results: The best fit to the experimental data at low energies shows χ2/F ≈7.7 per data point, which corresponds to an average deviation of about 30% between the best fit and the experimental data. Several combinations of the various ingredients of the statistical model are able to reach a reasonably small χ2/F , not exceeding the best-fit result by more than a factor of 2. Conclusions: The present experimental data for 64Zn in combination with the statistical model calculations allow us to constrain the astrophysical reaction rate within about a factor of 2. However, the significant excess of χ2/F of the best fit from unity demands further improvement of the statistical model calculations and, in particular, the α -nucleus potential.

  7. Amyloid-β-induced Synapse Damage Is Mediated via Cross-linkage of Cellular Prion Proteins

    PubMed Central

    Bate, Clive; Williams, Alun

    2011-01-01

    The cellular prion protein (PrPC), which is highly expressed at synapses, was identified as a receptor for the amyloid-β (Aβ) oligomers that are associated with dementia in Alzheimer disease. Here, we report that Aβ oligomers secreted by 7PA2 cells caused synapse damage in cultured neurons via a PrPC-dependent process. Exogenous PrPC added to Prnp knock-out(0/0) neurons was targeted to synapses and significantly increased Aβ-induced synapse damage. In contrast, the synapse damage induced by a phospholipase A2-activating peptide was independent of PrPC. In Prnp wild-type(+/+) neurons Aβ oligomers activated synaptic cytoplasmic phospholipase A2 (cPLA2). In these cells, the addition of Aβ oligomers triggered the translocation of cPLA2 in synapses to cholesterol dense membranes (lipid rafts) where it formed a complex also containing Aβ and PrPC. In contrast, the addition of Aβ to Prnp(0/0) neurons did not activate synaptic cPLA2, which remained in the cytoplasm and was not associated with Aβ. Filtration assays and non-denaturing gels demonstrated that Aβ oligomers cross-link PrPC. We propose that it is the cross-linkage of PrPC by Aβ oligomers that triggers abnormal activation of cPLA2 and synapse damage. This hypothesis was supported by our observation that monoclonal antibody mediated cross-linkage of PrPC also activated synaptic cPLA2 and caused synapse damage. PMID:21900234

  8. Carbon-Starvation Induces Cross-Resistance to Thermal, Acid, and Oxidative Stress in Serratia marcescens

    PubMed Central

    Pittman, Joseph R.; Kline, La’Kesha C.; Kenyon, William J.

    2015-01-01

    The broad host-range pathogen Serratia marcescens survives in diverse host and non-host environments, often enduring conditions in which the concentration of essential nutrients is growth-limiting. In such environments, carbon and energy source starvation (carbon-starvation) is one of the most common forms of stress encountered by S. marcescens. Related members of the family Enterobacteriaceae are known to undergo substantial changes in gene expression and physiology in response to the specific stress of carbon-starvation, enabling non-spore-forming cells to survive periods of prolonged starvation and exposure to other forms of stress (i.e., starvation-induced cross-resistance). To determine if carbon-starvation also results in elevated levels of cross-resistance in S. marcescens, both log-phase and carbon-starved cultures, depleted of glucose before the onset of high cell-density stationary-phase, were grown in minimal media at either 30 °C or 37 °C and were then challenged for resistance to high temperature (50 °C), low pH (pH 2.8), and oxidative stress (15 mM H2O2). In general, carbon-starved cells exhibited a higher level of resistance to thermal stress, acid stress, and oxidative stress compared to log-phase cells. The extent of carbon-starvation-induced cross-resistance was dependent on incubation temperature and on the particular strain of S. marcescens. In addition, strain- and temperature-dependent variations in long-term starvation survival were also observed. The enhanced stress-resistance of starved S. marcescens cells could be an important factor in their survival and persistence in many non-host environments and within certain host microenvironments where the availability of carbon sources is suboptimal for growth. PMID:27682115

  9. A copper-hydrogen peroxide redox system induces dityrosine cross-links and chemokine oligomerisation.

    PubMed

    MacGregor, Helen J; Kato, Yoji; Marshall, Lindsay J; Nevell, Thomas G; Shute, Janis K

    2011-12-01

    The activity of the chemoattractant cytokines, the chemokines, in vivo is enhanced by oligomerisation and aggregation on glycosaminoglycan (GAG), particularly heparan sulphate, side chains of proteoglycans. The chemokine RANTES (CCL5) is a T-lymphocyte and monocyte chemoattractant, which has a minimum tetrameric structure for in vivo activity and a propensity to form higher order oligomers. RANTES is unusual among the chemokines in having five tyrosine residues, an amino acid susceptible to oxidative cross-linking. Using fluorescence emission spectroscopy, Western blot analysis and LCMS-MS, we show that a copper/H2O2 redox system induces the formation of covalent dityrosine cross-links and RANTES oligomerisation with the formation of tetramers, as well as higher order oligomers. Amongst the transition metals tested, namely copper, nickel, mercury, iron and zinc, copper appeared unique in this respect. At high (400 μM) concentrations of H2O2, RANTES monomers, dimers and oligomers are destroyed, but heparan sulphate protects the chemokine from oxidative damage, promoting dityrosine cross-links and multimer formation under oxidative conditions. Low levels of dityrosine cross-links were detected in copper/H2O2-treated IL-8 (CXCL8), which has one tyrosine residue, and none were detected in ENA-78 (CXCL5), which has none. Redox-treated RANTES was fully functional in Boyden chamber assays of T-cell migration and receptor usage on activated T-cells following RANTES oligomerisation was not altered. Our results point to a protective, anti-oxidant, role for heparan sulphate and a previously unrecognised role for copper in chemokine oligomerisation that may offer an explanation for the known anti-inflammatory effect of copper-chelators such as penicillamine and tobramycin.

  10. Supplier-induced demand: re-examining identification and misspecification in cross-sectional analysis.

    PubMed

    Peacock, Stuart J; Richardson, Jeffrey R J

    2007-09-01

    This paper re-examines criticisms of cross-sectional methods used to test for supplier-induced demand (SID) and re-evaluates the empirical evidence using data from Australian medical services. Cross-sectional studies of SID have been criticised on two grounds. First, and most important, the inclusion of the doctor supply in the demand equation leads to an identification problem. This criticism is shown to be invalid, as the doctor supply variable is stochastic and depends upon a variety of other variables including the desirability of the location. Second, cross-sectional studies of SID fail diagnostic tests and produce artefactual findings due to model misspecification. Contrary to this, the re-evaluation of cross-sectional Australian data indicate that demand equations that do not include the doctor supply are misspecified. Empirical evidence from the re-evaluation of Australian medical services data supports the notion of SID. Demand and supply equations are well specified and have very good explanatory power. The demand equation is identified and the desirability of a location is an important predictor of the doctor supply. Results show an average price elasticity of demand of 0.22 and an average elasticity of demand with respect to the doctor supply of 0.46, with the impact of SID becoming stronger as the doctor supply rises. The conclusion we draw from this paper is that two of the main criticisms of the empirical evidence supporting the SID hypothesis have been inappropriately levelled at the methods used. More importantly, SID provides a satisfactory, and robust, explanation of the empirical data on the demand for medical services in Australia.

  11. Both cross-links and monoadducts induced in DNA by psoralens can lead to sister chromatid exchange formation

    SciTech Connect

    Cortes, F. Facultad de Biologia, Sevilla ); Morgan, W.F.; Varcarcel, E.R.; Cleaver, J.E.; Wolff, S. )

    1991-09-01

    The relative importance of DNA-DNA cross-links and bulky monoadducts in sister chromatid exchange (SCE) formation was investigated in three human fibroblast cell lines with different repair capabilities. These cell lines included normal cells, which can repair both classes of lesion; xeroderma pigmentosum (XP) cells, which cannot repair either psoralen-induced cross-links or monoadducts; and an XP revertant that repairs only cross-links and not monoadducts. SCEs were induced by two psoralen derivatives. After activation with long-wave ultraviolet light, HMT produces cross-links and monoadducts in DNA, whereas 5-MIP produces only monoadducts. In normal human cells both psoralens induced SCEs, but if cells were allowed to repair for 18 h before bromodeoxyuridine (BrdUrd) was added for SCE analysis, the SCE frequency was significantly reduced. XP cells showed an SCE frequency that remained high regardless of whether SCEs were analyzed immediately after psoralen exposure of 18 h later. In the XP revertant that repairs only cross-links, both psoralens induced a high yield of SCEs when BrdUrd was added immediately after psoralen treatment. These observations indicate that both cross-links and monoadducts are lesions in DNA that can lead to SCE formation.

  12. Early resistance training-induced increases in muscle cross-sectional area are concomitant with edema-induced muscle swelling.

    PubMed

    Damas, Felipe; Phillips, Stuart M; Lixandrão, Manoel E; Vechin, Felipe C; Libardi, Cleiton A; Roschel, Hamilton; Tricoli, Valmor; Ugrinowitsch, Carlos

    2016-01-01

    It has been proposed that skeletal muscle shows signs of resistance training (RT)-induced muscle hypertrophy much earlier (i.e., ~3-4 weeks of RT) than previously thought. We determined if early increases in whole muscle cross-sectional area (CSA) during a period of RT were concomitant with edematous muscle swelling and thus not completely attributable to hypertrophy. We analyzed vastus lateralis muscle ultrasound CSA images and their respective echo intensities (CSA-USecho) at the beginning (T1), in the 3rd week of RT (T2) and at the end (T3) of a 10-week RT period in ten untrained young men. Functional parameters [training volume (TV = load × reps × sets) and maximal voluntary contraction (MVC)] and muscle damage markers (myoglobin and interleukin-6) were also assessed. Muscle CSA increased significantly at T2 (~2.7%) and T3 (~10.4%) versus T1. Similarly, CSA-USecho increased at T2 (~17.2%) and T3 (~13.7%). However, when CSA-USecho was normalized to the increase in muscle CSA, only T2 showed a significantly higher USecho versus T1. Additionally, TV increased at T2 and T3 versus T1, but MVC increased only at T3. Myoglobin and Interleukin-6 were elevated at T2 versus T1, and myoglobin was also higher at T2 versus T3. We propose that early RT-induced increases in muscle CSA in untrained young individuals are not purely hypertrophy, since there is concomitant edema-induced muscle swelling, probably due to muscle damage, which may account for a large proportion of the increase. Therefore, muscle CSA increases (particularly early in an RT program) should not be labeled as hypertrophy without some concomitant measure of muscle edema/damage.

  13. Natural and cross-inducible anti-SIV antibodies in Mauritian cynomolgus macaques.

    PubMed

    Li, Hongzhao; Nykoluk, Mikaela; Li, Lin; Liu, Lewis R; Omange, Robert W; Soule, Geoff; Schroeder, Lukas T; Toledo, Nikki; Kashem, Mohammad Abul; Correia-Pinto, Jorge F; Liang, Binhua; Schultz-Darken, Nancy; Alonso, Maria J; Whitney, James B; Plummer, Francis A; Luo, Ma

    2017-01-01

    Cynomolgus macaques are an increasingly important nonhuman primate model for HIV vaccine research. SIV-free animals without pre-existing anti-SIV immune responses are generally needed to evaluate the effect of vaccine-induced immune responses against the vaccine epitopes. Here, in order to select such animals for vaccine studies, we screened 108 naïve female Mauritian cynomolgus macaques for natural (baseline) antibodies to SIV antigens using a Bio-Plex multiplex system. The antigens included twelve 20mer peptides overlapping the twelve SIV protease cleavage sites (-10/+10), respectively (PCS peptides), and three non-PCS Gag or Env peptides. Natural antibodies to SIV antigens were detected in subsets of monkeys. The antibody reactivity to SIV was further confirmed by Western blot using purified recombinant SIV Gag and Env proteins. As expected, the immunization of monkeys with PCS antigens elicited anti-PCS antibodies. However, unexpectedly, antibodies to non-PCS peptides were also induced, as shown by both Bio-Plex and Western blot analyses, while the non-PCS peptides do not share sequence homology with PCS peptides. The presence of natural and vaccine cross-inducible SIV antibodies in Mauritian cynomolgus macaques should be considered in animal selection, experimental design and result interpretation, for their best use in HIV vaccine research.

  14. Riboflavin-ultraviolet-A-induced collagen cross-linking treatments in improving dentin bonding.

    PubMed

    Chiang, Yung-Show; Chen, Yuh-Ling; Chuang, Shu-Fen; Wu, Ching-Ming; Wei, Pal-Jen; Han, Chang-Fu; Lin, Jui-Che; Chang, Hsiao-Tzu

    2013-06-01

    To evaluate the collagen cross-linkers, riboflavin-ultraviolet-A (RF/UVA) and glutaraldehyde, with regard to their efficacy in cross-linking the dentinal collagen and improving dentin bonding. Glutaraldehyde and different RF/UVA protocols (0.1%RF/1-minUV, 0.1%RF/2-minUV, and 1%RF/1-minUV) were first evaluated by gel electrophoresis to determine their abilities of collagen cross-linking. The mechanical properties of acid-etched dentin receiving these cross-linking treatments were examined in either dry or wet condition by a nanoindentation test. Fifteen teeth with exposed occlusal dentin received the microtensile bond strength (μTBS) test. The teeth were primed either with RF/UVA or glutaraldehyde, followed by adhesive treatment and composite restorations, and then cut into resin-dentin microbeams. Half of the microbeams received the μTBS test after 24h, and the other half received test after 5000 thermocycles. Nanoleakage at the bond interface was examined under TEM. The alignments of collagen fibrils in the hybrid layers were also defined by an image analysis. Gel electrophoresis showed that glutaraldehyde induced strong collagen gelation, while RF/UVA generated milder collagen cross-linking. Glutaraldehyde, 0.1%RF/2-min-UVA, and 1%RF/1-minUV showed higher stiffness compared to untreated and 0.1%RF/1-minUV in wet condition. All the crosslinking treatments improved early μTBS, but 0.1%RF/2-minUVA treatment maintained high μTBS after theromocycles. Under TEM, glutaraldehyde-treated dentin showed dense and enclosed collagen network on the adhesive interface. 0.1%RF/2-minUVA showed the least nanoleakage, and this could be associated with the suspended collagen fibrils in the hybrid layer. 0.1%RF/2-minUVA treatment enhanced resin-dentin bond possibly through enhancing the stiffness and maintaining the expanding collagen matrix in the hybrid layer. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  15. Thermally induced transverse cracking in graphite-epoxy cross-ply laminates

    NASA Technical Reports Server (NTRS)

    Adams, D. S.; Bowles, D. E.; Herakovich, C. T.

    1986-01-01

    Thermally induced transverse cracking in T300/5208 graphite-epoxy cross-ply laminates was investigated experimentally and theoretically. The six laminate configurations studied were: 0/90(3)s, 0(2)/90(2)s, 0(3)/90s, 90/0(3)s, 90(2)/0(2)s, and 90(3)/0s. The thermal load required to initiate transverse cracking was determined experimentally and compared to a theoretical prediction. Experimental results for the accumulation of transverse cracks under cyclic thermal loading between - 250 and 250 F for up to 500 thermal cycles are presented. The calculated in situ transverse-lamina strength was determined to be at least 1.9 times the unidirectional-lamina transverse tensile strength. All laminate configurations exhibited an increase in crack density with increasing thermal cycles.

  16. Transitions induced by cross-correlated bounded noises and time delay in a genotype selection model

    NASA Astrophysics Data System (ADS)

    Liu, Pei; Ning, Li Juan

    2016-01-01

    We present a numerical investigation of occurrence of transitions in a genotype selection model with time delay, where two bounded noises are cross-correlated. Stationary probability distribution (SPD) function is obtained. It is found that: the multiplicative bounded noise can facilitate the gene separation and it plays a constructive role in the genetic selection progress, while the additive bounded noise suppresses the gene separation. The strong correlation between noises gives a big chance to one type haploid out of the group. Besides, what is more interesting is that the correlation time τ can induce a new transitions (i.e., the curve of the SPD changes from unimodal to bimodal, and then to four peaks as the correlation time τ increases).

  17. The impact of protein cross-linking induced by alkali on the quality of buckwheat noodles.

    PubMed

    Guo, Xiao-Na; Wei, Xiao-Ming; Zhu, Ke-Xue

    2017-04-15

    The impact of alkali addition on the dough rheological properties and quality of buckwheat noodles was investigated. Farinograph measurements showed that the addition of alkali increased the water absorption and development time of the dough. Dynamic rheological properties analysis showed that alkali addition enhanced G' and G″ of dough. In addition, the texture properties of buckwheat noodles improved by the increase of the hardness and tensile force. Furthermore, an obvious decrease in the intensity of the protein bands with lower molecular weights was observed in SDS-PAGE patterns and the extractability of protein in sodium dodecyl sulfate containing medium (SDSEP) decreased, which demonstrated that alkali addition promoted the degree of protein polymerization in the buckwheat noodles. CLSM analysis showed alkali addition produced a tight and continuous protein network in buckwheat noodles. The protein cross-linking induced by alkali improved rheological properties of dough and texture properties of buckwheat noodles.

  18. ANALYSIS OF SEEING-INDUCED POLARIZATION CROSS-TALK AND MODULATION SCHEME PERFORMANCE

    SciTech Connect

    Casini, R.; De Wijn, A. G.; Judge, P. G.

    2012-09-20

    We analyze the generation of polarization cross-talk in Stokes polarimeters by atmospheric seeing, and its effects on the noise statistics of spectropolarimetric measurements for both single-beam and dual-beam instruments. We investigate the time evolution of seeing-induced correlations between different states of one modulation cycle and compare the response to these correlations of two popular polarization modulation schemes in a dual-beam system. Extension of the formalism to encompass an arbitrary number of modulation cycles enables us to compare our results with earlier work. Even though we discuss examples pertinent to solar physics, the general treatment of the subject and its fundamental results might be useful to a wider community.

  19. Short-pulse cross-phase modulation in an electromagnetically-induced-transparency medium

    NASA Astrophysics Data System (ADS)

    Feizpour, Amir; Dmochowski, Greg; Steinberg, Aephraim M.

    2016-01-01

    Electromagnetically induced transparency (EIT) has been proposed as a way to greatly enhance cross-phase modulation, with the possibility of leading to few-photon-level optical nonlinearities [Schmidt and Imamoglu, Opt. Lett. 21, 1936 (1996), 10.1364/OL.21.001936]. This enhancement grows as the transparency window width, ΔEIT, is narrowed. Decreasing ΔEIT, however, has been shown to increase the response time of the nonlinear medium. This suggests that, for a given pulse duration, the nonlinearity would diminish once the window width became narrower than this pulse bandwidth. We show that this is not the case: the peak phase shift saturates but does not decrease. We show that in the regimes of most practical interest—narrow EIT windows perturbed by short signal pulses—the enhancement offered by EIT is not only in the magnitude of the nonlinear phase shift but also in its increased duration. That is, for the case of signal pulses much shorter (temporally) than the inverse EIT bandwidth, the narrow window serves to prolong the effect of the passing signal pulse, leading to an integrated phase shift that grows linearly with 1 /ΔEIT ; this continued growth of the integrated phase shift improves the detectability of the phase shift, in principle, without bound. For many purposes, it is this detectability which is of more interest than the absolute magnitude of the peak phase shift. We present analytical expressions based on a linear time-invariant model that accounts for the temporal behavior of the cross-phase modulation for several parameter ranges of interest. We conclude that in order to optimize the detectability of the EIT-based cross-phase shift, one should use the narrowest possible EIT window and a signal pulse that is as broadband as the excited-state linewidth and detuned by half a linewidth.

  20. Dopamine-induced α-synuclein oligomers show self- and cross-propagation properties.

    PubMed

    Planchard, Matthew S; Exley, Sarah E; Morgan, Sarah E; Rangachari, Vijayaraghavan

    2014-10-01

    Amyloid aggregates of α-synuclein (αS) protein are the predominant species present within the intracellular inclusions called Lewy bodies in Parkinson's disease (PD) patients. Among various aggregates, the low-molecular weight ones broadly ranging between 2 and 30 mers are known to be the primary neurotoxic agents responsible for the impairment of neuronal function. Recent research has indicated that the neurotransmitter dopamine (DA) is one of the key physiological agents promoting and augmenting αS aggregation, which is thought to be a significant event in PD pathologenesis. Specifically, DA is known to induce the formation of soluble oligomers of αS, which in turn are responsible for inducing several important cellular changes leading to cellular toxicity. In this report, we present the generation, isolation, and biophysical characterization of five different dopamine-derived αS oligomers (DSOs) ranging between 3 and 15 mers, corroborating previously published reports. More importantly, we establish that these DSOs are also capable of replication by self-propagation, which leads to the replication of DSOs upon interaction with αS monomers, a process similar to that observed in mammilian prions. In addition, DSOs are also able to cross-propagate amyloid-β (Aβ) aggregates involved in Alzheimer's disease (AD). Interestingly, while self-propagation of DSOs occur with no net gain in protein structure, cross-propagation proceeds with an overall gain in β-sheet conformation. These results implicate the involvement of DSOs in the progression of PD, and, in part, provide a molecular basis for the observed co-existence of AD-like pathology among PD patients.

  1. Dopamine-induced α-synuclein oligomers show self- and cross-propagation properties

    PubMed Central

    Planchard, Matthew S; Exley, Sarah E; Morgan, Sarah E; Rangachari, Vijayaraghavan

    2014-01-01

    Amyloid aggregates of α-synuclein (αS) protein are the predominant species present within the intracellular inclusions called Lewy bodies in Parkinson’s disease (PD) patients. Among various aggregates, the low-molecular weight ones broadly ranging between 2 and 30 mers are known to be the primary neurotoxic agents responsible for the impairment of neuronal function. Recent research has indicated that the neurotransmitter dopamine (DA) is one of the key physiological agents promoting and augmenting αS aggregation, which is thought to be a significant event in PD pathologenesis. Specifically, DA is known to induce the formation of soluble oligomers of αS, which in turn are responsible for inducing several important cellular changes leading to cellular toxicity. In this report, we present the generation, isolation, and biophysical characterization of five different dopamine-derived αS oligomers (DSOs) ranging between 3 and 15 mers, corroborating previously published reports. More importantly, we establish that these DSOs are also capable of replication by self-propagation, which leads to the replication of DSOs upon interaction with αS monomers, a process similar to that observed in mammilian prions. In addition, DSOs are also able to cross-propagate amyloid-β (Aβ) aggregates involved in Alzheimer’s disease (AD). Interestingly, while self-propagation of DSOs occur with no net gain in protein structure, cross-propagation proceeds with an overall gain in β-sheet conformation. These results implicate the involvement of DSOs in the progression of PD, and, in part, provide a molecular basis for the observed co-existence of AD-like pathology among PD patients. PMID:25044276

  2. Cross-Country Differences in Basal and Stress-Induced Cortisol Secretion in Older Adults

    PubMed Central

    Lupien, Sonia J.; Fiocco, Alexandra; Suchecki, Deborah

    2014-01-01

    Objective Several studies have emphasized the association between socioeconomic status (SES) and inadequate response of the biological stress system. However, other factors related to SES are rarely considered, such as cultural values, social norms, organization, language and communication skills, which raises the need to investigate cross-country differences in stress response. Although some studies have shown differences in cortisol levels between immigrants and natives, there is no cross-country evidence regarding cortisol levels in country-native elders. This is particularly important given the high prevalence of stress-related disorders across nations during aging. The current study examined basal diurnal and reactive cortisol levels in healthy older adults living in two different countries. Methods Salivary cortisol of 260 older adults from Canada and Brazil were nalyzed. Diurnal cortisol was measured in saliva samples collected at home throughout two working days at awakening, 30 min after waking, 1400 h, 1600 h and before bedtime. Cortisol reactivity was assessed in response to the Trier Social Stress Test (TSST) in both populations. Results Our results showed that even under similar health status, psychological and cognitive characteristics, Brazilian elders exhibited higher basal and stress-induced cortisol secretion compared to the Canadian participants. Conclusion These findings suggest that country context may modulate cortisol secretion and could impact the population health. PMID:25153322

  3. Multiple cross-correlation noise induced transition in a stochastic bistable system

    NASA Astrophysics Data System (ADS)

    Wang, Can-Jun; Yang, Ke-Li; Du, Chun-Yan

    2017-03-01

    Based on the stochastic equivalent rules, the Fokker-Planck Equation for a general one-dimensional nonlinear system subjected to N-component noises and cross-correlation noises is derived, and the greatest advantage of the method lies in its simplicity. Applying this method, the effects of multiple sources of noise and the correlation forms of noises among them (i.e., two multiplicative noises, an additive noise and the correlation between the three noises) on the steady-state properties and the mean first passage time (MFPT) of a stochastic bistable system are discussed in details. The results show rich transition phenomena, such as the reentrance-like noise-induced phenomenon and the switch between the bimodal and the unimodal structure for different noise intensities. Moreover, the effects of the cross-correlation among the three noise sources on the MFPT are also discussed, and the noise-enhanced stability phenomenon and the resonant activation phenomenon are observed. The numerical results are in basic agreement with the theoretical predictions.

  4. HIV Protease Inhibitor-Induced Cathepsin Modulation Alters Antigen Processing and Cross-Presentation.

    PubMed

    Kourjian, Georgio; Rucevic, Marijana; Berberich, Matthew J; Dinter, Jens; Wambua, Daniel; Boucau, Julie; Le Gall, Sylvie

    2016-05-01

    Immune recognition by T cells relies on the presentation of pathogen-derived peptides by infected cells, but the persistence of chronic infections calls for new approaches to modulate immune recognition. Ag cross-presentation, the process by which pathogen Ags are internalized, degraded, and presented by MHC class I, is crucial to prime CD8 T cell responses. The original degradation of Ags is performed by pH-dependent endolysosomal cathepsins. In this article, we show that HIV protease inhibitors (PIs) prescribed to HIV-infected persons variably modulate cathepsin activities in human APCs, dendritic cells and macrophages, and CD4 T cells, three cell subsets infected by HIV. Two HIV PIs acted in two complementary ways on cathepsin hydrolytic activities: directly on cathepsins and indirectly on their regulators by inhibiting Akt kinase activities, reducing NADPH oxidase 2 activation, and lowering phagolysosomal reactive oxygen species production and pH, which led to enhanced cathepsin activities. HIV PIs modified endolysosomal degradation and epitope production of proteins from HIV and other pathogens in a sequence-dependent manner. They altered cross-presentation of Ags by dendritic cells to epitope-specific T cells and T cell-mediated killing. HIV PI-induced modulation of Ag processing partly changed the MHC self-peptidome displayed by primary human cells. This first identification, to our knowledge, of prescription drugs modifying the regulation of cathepsin activities and the MHC-peptidome may provide an alternate therapeutic approach to modulate immune recognition in immune disease beyond HIV.

  5. Cross-modal prediction changes the timing of conscious access during the motion-induced blindness.

    PubMed

    Chang, Acer Y C; Kanai, Ryota; Seth, Anil K

    2015-01-01

    Despite accumulating evidence that perceptual predictions influence perceptual content, the relations between these predictions and conscious contents remain unclear, especially for cross-modal predictions. We examined whether predictions of visual events by auditory cues can facilitate conscious access to the visual stimuli. We trained participants to learn associations between auditory cues and colour changes. We then asked whether congruency between auditory cues and target colours would speed access to consciousness. We did this by rendering a visual target subjectively invisible using motion-induced blindness and then gradually changing its colour while presenting congruent or incongruent auditory cues. Results showed that the visual target gained access to consciousness faster in congruent than in incongruent trials; control experiments excluded potentially confounding effects of attention and motor response. The expectation effect was gradually established over blocks suggesting a role for extensive training. Overall, our findings show that predictions learned through cross-modal training can facilitate conscious access to visual stimuli. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Light ion induced L X-ray production cross-sections in Au and Pb

    NASA Astrophysics Data System (ADS)

    Ouziane, S.; Amokrane, A.; Toumert, I.

    2008-04-01

    Experimental proton-induced Lα, Lβ, Lγ, Lℓ and Ltot absolute X-ray production cross-sections for Au and Pb in the incident proton energy range between 1 and 2.5 MeV are presented. The experimental results for X-ray production cross-sections are compared to available data given in Sokhi and Crumpton [R.S. Sokhi, D. Crumpton, At. Data Nucl. Data Tables 30 (1984) 49], Jesus et al. [A.P. Jesus, J.S. Lopes, J.P. Ribeiro, J. Phys. B: At. Mol. Phys. 18 (1985) 2456; A.P. Jesus, T.M. Pinheiro, I.A. Nisa, J.P. Ribeiro, J.S. Lopes, Nucl. Instrum. Methods B15 (1986) 95] and Goudarzi et al. [M. Goudarzi, F. Shokouhi, M. Lamehi-Rachti, P.Olialiy, Nucl. Instrum. Methods Phys. Res. B247 (2006) 218]. The given data are also compared with the predictions of ECPSSR model [W. Brandt, G. Lapicki, Phys. Rev. A23 (1981) 1717].

  7. Caffeine and amphetamine produce cross-sensitization to nicotine-induced locomotor activity in mice.

    PubMed

    Celik, Eylem; Uzbay, I Tayfun; Karakas, Sirel

    2006-01-01

    Sensitization development is linked to the addictive potential of the drugs. The same mechanisms might play a role in sensitization development to the different addictive drugs. The aim of the study was to investigate the development of cross-sensitization to caffeine and amphetamine in nicotine-induced locomotor sensitization in mice. Caffeine (2.5-20 mg/kg), amphetamine (1-16 mg/kg) or saline were injected to Swiss-Webster mice and locomotor activity was recorded for 30 min. Nicotine (0.5-2 mg/kg) or saline were injected to mice and locomotor activity was recorded for 30 min. Process was applied for 19 days, every other day (10 sessions). Caffeine (5 mg/kg), amphetamine (4 mg/kg) or saline were challenged to the different groups of nicotine-sensitized mice 2 days later on the last nicotine injection, and locomotor activity was recorded. Repetitive injections of nicotine (0.5-2 mg) produced locomotor sensitization in mice. After caffeine and amphetamine challenge injections, locomotor activity of the nicotine-sensitized mice was found to be significantly higher than saline-pretreated mice. Saline challenge did not produce any significant effect in nicotine- or saline-pretreated mice. Our results suggest that a cross-sensitization developed to both caffeine and amphetamine in nicotine-sensitized mice. In conclusion, similar central mechanisms may be responsible for the development of addiction to these substances.

  8. Quantum-mechanical predictions of electron-induced ionization cross sections of DNA components

    SciTech Connect

    Champion, Christophe

    2013-05-14

    Ionization of biomolecules remains still today rarely investigated on both the experimental and the theoretical sides. In this context, the present work appears as one of the first quantum mechanical approaches providing a multi-differential description of the electron-induced ionization process of the main DNA components for impact energies ranging from the target ionization threshold up to about 10 keV. The cross section calculations are here performed within the 1st Born approximation framework in which the ejected electron is described by a Coulomb wave whereas the incident and the scattered electrons are both described by a plane wave. The biological targets of interest, namely, the DNA nucleobases and the sugar-phosphate backbone, are here described by means of the GAUSSIAN 09 system using the restricted Hartree-Fock method with geometry optimization. The theoretical predictions also obtained have shown a reasonable agreement with the experimental total ionization cross sections while huge discrepancies have been pointed out with existing theoretical models, mainly developed within a semi-classical framework.

  9. Clinical Use of Colistin Induces Cross-Resistance to Host Antimicrobials in Acinetobacter baumannii

    PubMed Central

    Napier, Brooke A.; Burd, Eileen M.; Satola, Sarah W.; Cagle, Stephanie M.; Ray, Susan M.; McGann, Patrick; Pohl, Jan; Lesho, Emil P.; Weiss, David S.

    2013-01-01

    ABSTRACT The alarming rise in antibiotic resistance has led to an increase in patient mortality and health care costs. This problem is compounded by the absence of new antibiotics close to regulatory approval. Acinetobacter baumannii is a human pathogen that causes infections primarily in patients in intensive care units (ICUs) and is highly antibiotic resistant. Colistin is one of the last-line antibiotics for treating A. baumannii infections; however, colistin-resistant strains are becoming increasingly common. This cationic antibiotic attacks negatively charged bacterial membranes in a manner similar to that seen with cationic antimicrobials of the innate immune system. We therefore set out to determine if the increasing use of colistin, and emergence of colistin-resistant strains, is concomitant with the generation of cross-resistance to host cationic antimicrobials. We found that there is indeed a positive correlation between resistance to colistin and resistance to the host antimicrobials LL-37 and lysozyme among clinical isolates. Importantly, isolates obtained before and after treatment of individual patients demonstrated that colistin use correlated with increased resistance to cationic host antimicrobials. These data reveal the overlooked risk of inducing cross-resistance to host antimicrobials when treating patients with colistin as a last-line antibiotic. PMID:23695834

  10. Neutron-Induced Fission Cross Section Measurements for Uranium Isotopes and Other Actinides at LANSCE

    SciTech Connect

    Laptev, Alexander B.; Tovesson, Fredrik K.; Hill, Tony S.

    2012-08-16

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). The incident neutron energy range spans from sub-thermal up to 200 MeV by combining two LANSCE facilities, the Lujan Center and the Weapons Neutron Research center (WNR). The time-of-flight method is implemented to measure the incident neutron energy. A parallel-plate fission ionization chamber was used as a fission fragment detector. The event rate ratio between the investigated foil and a standard {sup 235}U foil is translated into a fission cross section ratio. Thin actinide targets with deposits of <200 {micro}g/cm{sup 2} on stainless steel backing were loaded into a fission chamber. In addition to previously measured data for {sup 237}Np, {sup 239-242}Pu, {sup 243}Am, new measurements include the recently completed {sup 233,238}U isotopes, {sup 236}U data which is being analyzed, and {sup 234}U data acquired in the 2011-2012 LANSCE run cycle. The new data complete the full suite of Uranium isotopes which were investigated with this experimental approach. When analysis of the new measured data is completed, data will be delivered to evaluators. Having data for multiple Uranium isotopes will support theoretical modeling capabilities and strengthens nuclear data evaluation.

  11. Towards an improved evaluation of neutron-induced fission cross sections on actinides

    NASA Astrophysics Data System (ADS)

    Goriely, S.; Hilaire, S.; Koning, A. J.; Capote, R.

    2011-03-01

    Mean-field calculations can now provide all the nuclear ingredients required to describe the fission path from the equilibrium deformation up to the nuclear scission point. The information obtained from microscopic mean-field models has been included in the TALYS reaction code to improve the predictions of neutron-induced fission cross sections. The nuclear inputs concern not only the details of the energy surface along the fission path, but also the coherent estimate of the nuclear level density derived within the combinatorial approach on the basis of the same single-particle properties, in particular at the fission saddle points. The predictive power of such a microscopic approach is tested on the experimental data available for the uranium isotopic chain. It is also shown that the various inputs can be tuned to reproduce, at best, experimental data in one unique coherent framework, so that in a close future it should become possible to make, on the basis of such models, accurate fission-cross-section calculations and the corresponding estimates for nuclei, energy ranges, or reaction channels for which no data exist. Such model uncertainties are usually not taken into account in data evaluations.

  12. Lack of gender difference in motion sickness induced by vestibular Coriolis cross-coupling.

    PubMed

    Cheung, Bob; Hofer, Kevin

    It has been reported that females are more susceptible to motion sickness than males. Supporting evidence is primarily based on retrospective survey questionnaires and self-reporting. We investigated if there is a gender difference in motion sickness susceptibility using objective and subjective measurements under controlled laboratory conditions. Thirty healthy subjects (14 males and 16 females) between the ages of 18-46 years were exposed to Coriolis cross-coupling stimulation, induced by 120 degrees /s yaw rotation and a simultaneous 45 degrees pitch forward head movement in the sagittal plane every 12 seconds. Cutaneous forearm and calf blood flow, blood pressure, and heart rate were monitored. Graybiel's diagnostic criteria were used to assess sickness susceptibility before and after motion exposure. Golding and Kerguelen's scale was used to assess the severity of symptoms during motion exposure. A significant (p<0.01) increase of forearm and calf blood flow during cross-coupling stimulation was observed in both sexes. However, the subjective symptoms rating and blood flow measurements indicate that there was no significant difference between male and female subjects. Our data also suggests that females may be more inclined to admit discomfort as indicated by their responses to a survey of motion sickness history prior to the experiment.

  13. Total fission cross section of {sup 181}Ta and {sup 208}Pb induced by protons at relativistic energies

    SciTech Connect

    Ayyad, Y.; Benlliure, J.; Casarejos, E.; Schmidt, K. H.; Jurado, B.; Pol, H. A.; Ricciardi, M. V.; Pleskac, R.; Enqvist, T.; Rejmund, F.; Giot, L.; Henzl, V.; Lukic, S.; Ngoc, S. N.; Boudard, A.; Leray, S.; Kurtukian, T.; Schmitt, C.; Henzlova, D.; Paradela, C.; Bacquias, A.; Loureiro, D. P.; Foehr, V.; Tarrio, D.; Kezzar, K.

    2011-07-01

    Total fission cross section induced by protons in {sup 181}Ta and {sup 208}Pb at energies in the range of 300 to 1000 A MeV have been measured at GSI (Germany) using the inverse kinematics technique. A dedicated setup with high efficiency made it possible to determine these cross sections with high accuracy. The new data seed light in the controversial results obtained so far and contribute to the understanding of the fission process at high excitation energies. (authors)

  14. Neutron-induced fission cross section of 233Pa between 1.0 and 3.0 MeV.

    PubMed

    Tovesson, F; Hambsch, F J; Oberstedt, A; Fogelberg, B; Ramström, E; Oberstedt, S

    2002-02-11

    The energy dependent neutron-induced fission cross section of 233Pa has for the first time been measured directly with monoenergetic neutrons. This nuclide is an important intermediary in a thorium based fuel cycle, and its fission cross section is a key parameter in the modeling of future advanced fuel and reactor concepts. A first experiment resulted in four cross section values between 1.0 and 3.0 MeV, establishing a fission threshold in excess of 1 MeV. Significant discrepancies were found with a previous indirect experimental determination and with model estimates.

  15. Characterization of the Medley setup for measurements of neutron-induced fission cross sections at the GANIL-NFS facility

    NASA Astrophysics Data System (ADS)

    Tarrío, Diego; Prokofiev, Alexander V.; Gustavsson, Cecilia; Jansson, Kaj; Andersson-Sundén, Erik; Al-Adili, Ali; Pomp, Stephan

    2017-09-01

    Neutron-induced fission cross sections of 235U and 238U are widely used as standards for monitoring of neutron beams and fields. An absolute measurement of these cross sections at an absolute scale, i.e., versus the H(n,p) scattering cross section, is planned with the white neutron beam under construction at the Neutrons For Science (NFS) facility in GANIL. The experimental setup, based on PPACs and ΔE-ΔE-E telescopes containing Silicon and CsI(Tl) detectors, is described. The expected uncertainties are discussed.

  16. Alpha-induced reaction cross-section for Sm, U, Np targets: influence of hexadecapole deformation and deformed surface diffuseness

    NASA Astrophysics Data System (ADS)

    Alavi, S. A.; Dehghani, V.

    2017-06-01

    Alpha-induced reactions on 154Sm, 233,235,236,238U, and 237Np deformed nuclei are studied theoretically. The effects of hexadecapole deformation, deformed surface diffuseness parameter, and orientation on barrier height and position, fusion cross-section at any angle, and fusion cross-section have been investigated. Both hexadecapole deformation and deformed surface diffuseness can affect barrier characteristics and enhance fusion cross-section. Good agreement between experimental data and theoretical calculations with quadrupole and hexadecapole deformation and deformed surface diffuseness were observed for the 4He+154Sm, 235U, 237Np reactions.

  17. Cross-conditional entropy and coherence analysis of pharmaco-EEG changes induced by alprazolam.

    PubMed

    Alonso, J F; Mañanas, M A; Romero, S; Rojas-Martínez, M; Riba, J

    2012-06-01

    Quantitative analysis of electroencephalographic signals (EEG) and their interpretation constitute a helpful tool in the assessment of the bioavailability of psychoactive drugs in the brain. Furthermore, psychotropic drug groups have typical signatures which relate biochemical mechanisms with specific EEG changes. To analyze the pharmacological effect of a dose of alprazolam on the connectivity of the brain during wakefulness by means of linear and nonlinear approaches. EEG signals were recorded after alprazolam administration in a placebo-controlled crossover clinical trial. Nonlinear couplings assessed by means of corrected cross-conditional entropy were compared to linear couplings measured with the classical magnitude squared coherence. Linear variables evidenced a statistically significant drug-induced decrease, whereas nonlinear variables showed significant increases. All changes were highly correlated to drug plasma concentrations. The spatial distribution of the observed connectivity changes clearly differed from a previous study: changes before and after the maximum drug effect were mainly observed over the anterior half of the scalp. Additionally, a new variable with very low computational cost was defined to evaluate nonlinear coupling. This is particularly interesting when all pairs of EEG channels are assessed as in this study. Results showed that alprazolam induced changes in terms of uncoupling between regions of the scalp, with opposite trends depending on the variables: decrease in linear ones and increase in nonlinear features. Maps provided consistent information about the way brain changed in terms of connectivity being definitely necessary to evaluate separately linear and nonlinear interactions.

  18. Rain induced cross polarization at millimeter waves in a Xi'an environment

    NASA Astrophysics Data System (ADS)

    Yi, Yan; Lijiun, Wang; Jiying, Huang

    1993-05-01

    The rainfall intensity accumulative distribution, raindrop size and canting angle distributions in Xi'an(108.9 E, 34.3 N) have been obtained from data measured over a long period of time. Rain induced crose polarization in this environment has been studied. The crose polarization discrimination, XPD, was compu ted over a frequency range of 19.3 to 300 GHz for non spherical drops. The variations of XPD with frequency, rainfall rate and copolar attenuation, CPA, were investigated. The computational resulte are in good agreement with experimental data. A mathematical relationship was established between the XPD and CPA, raindrop canting angle, which result is in good agreement with experimental data. The cumulative distribution of rain induced cross polarization for eleven years and in month have been ob tained with the cumulative distribution of the rain rate from the data measured from 1975 to 1985. The role of multiple scattering also has been discussed, it is shown that the multiple scattering play an important part in short millimeter wave.

  19. Antibodies induced with recombinant VP1 from human rhinovirus exhibit cross-neutralisation.

    PubMed

    Edlmayr, J; Niespodziana, K; Popow-Kraupp, T; Krzyzanek, V; Focke-Tejkl, M; Blaas, D; Grote, M; Valenta, R

    2011-01-01

    Human rhinoviruses (HRVs) are the major cause of the common cold and account for 30-50% of all acute respiratory illnesses. Although HRV infections are usually harmless and invade only the upper respiratory tract, several studies demonstrate that HRV is involved in the exacerbation of asthma. VP1 is one of the surface-exposed proteins of the viral capsid that is important for the binding of rhinoviruses to the corresponding receptors on human cells. Here we investigated its potential usefulness for vaccination against the common cold. We expressed VP1 proteins from two distantly related HRV strains, HRV89 and HRV14, in Escherichia coli. Mice and rabbits were immunised with the purified recombinant proteins. The induced antibodies reacted with natural VP1 and with whole virus particles as shown by immunoblotting and immunogold electron microscopy. They exhibited strong cross-neutralising activity for different HRV strains. Therefore, recombinant VP1 may be considered a candidate HRV vaccine to prevent HRV-induced asthma exacerbations.

  20. Use of Activated Carbon in Packaging to Attenuate Formaldehyde-Induced and Formic Acid-Induced Degradation and Reduce Gelatin Cross-Linking in Solid Dosage Forms.

    PubMed

    Colgan, Stephen T; Zelesky, Todd C; Chen, Raymond; Likar, Michael D; MacDonald, Bruce C; Hawkins, Joel M; Carroll, Sophia C; Johnson, Gail M; Space, J Sean; Jensen, James F; DeMatteo, Vincent A

    2016-07-01

    Formaldehyde and formic acid are reactive impurities found in commonly used excipients and can be responsible for limiting drug product shelf-life. Described here is the use of activated carbon in drug product packaging to attenuate formaldehyde-induced and formic acid-induced drug degradation in tablets and cross-linking in hard gelatin capsules. Several pharmaceutical products with known or potential vulnerabilities to formaldehyde-induced or formic acid-induced degradation or gelatin cross-linking were subjected to accelerated stability challenges in the presence and absence of activated carbon. The effects of time and storage conditions were determined. For all of the products studied, activated carbon attenuated drug degradation or gelatin cross-linking. This novel use of activated carbon in pharmaceutical packaging may be useful for enhancing the chemical stability of drug products or the dissolution stability of gelatin-containing dosage forms and may allow for the 1) extension of a drug product's shelf-life when the limiting attribute is a degradation product induced by a reactive impurity, 2) marketing of a drug product in hotter and more humid climatic zones than currently supported without the use of activated carbon, and 3) enhanced dissolution stability of products that are vulnerable to gelatin cross-linking.

  1. Susceptibility to quantum dot induced lung inflammation differs widely among the Collaborative Cross founder mouse strains

    PubMed Central

    Scoville, David K.; White, Collin C.; Botta, Dianne; McConnachie, Lisa A.; Zadworny, Megan E.; Schmuck, Stefanie C.; Hu, Xiaoge; Gao, Xiaohu; Yu, Jianbo; Dills, Russell L.; Sheppard, Lianne; Delaney, Martha A.; Griffith, William C.; Beyer, Richard P.; Zangar, Richard C.; Pounds, Joel G.; Faustman, Elaine M.; Kavanagh, Terrance J.

    2015-01-01

    Quantum dots (QDs) are engineered semiconductor nanoparticles with unique physicochemical properties that make them potentially useful in clinical, research and industrial settings. However, a growing body of evidence indicates that like other engineered nanomaterials, QDs have the potential to be respiratory hazards, especially in the context of the manufacture of QDs and products containing them, as well as exposures to consumers using these products. The overall goal of this study was to investigate the role of mouse strain in determining susceptibility to QD-induced pulmonary inflammation and toxicity. Male mice from 8 genetically diverse inbred strains (the Collaborative Cross founder strains) were exposed to CdSe–ZnS core–shell QDs stabilized with an amphiphilic polymer. QD treatment resulted in significant increases in the percentage of neutrophils and levels of cytokines present in bronchoalveolar lavage fluid (BALF) obtained from NOD/ShiLtJ and NZO/HlLtJ mice relative to their saline (Sal) treated controls. Cadmium measurements in lung tissue indicated strain-dependent differences in disposition of QDs in the lung. Total glutathione levels in lung tissue were significantly correlated with percent neutrophils in BALF as well as with lung tissue Cd levels. Our findings indicate that QD-induced acute lung inflammation is mouse strain dependent, that it is heritable, and that the choice of mouse strain is an important consideration in planning QD toxicity studies. These data also suggest that formal genetic analyses using additional strains or recombinant inbred strains from these mice could be useful for discovering potential QD-induced inflammation susceptibility loci. PMID:26476918

  2. Ranitidine-induced anaphylaxis: clinical features, cross-reactivity, and skin testing.

    PubMed

    Park, K H; Pai, J; Song, D-G; Sim, D W; Park, H J; Lee, J-H; Jeong, K Y; Pan, C-H; Shin, I; Park, J-W

    2016-04-01

    Histamine H2 receptor antagonists are commonly prescribed medications and are known to be well tolerated. However, 99 cases of ranitidine-induced anaphylaxis occurred in Korea from 2007 to 2014. The purpose of this study was to determine the incidence, clinical features, and diagnostic methods for ranitidine-induced anaphylaxis. Ranitidine-related pharmacovigilance data from 2007 to 2014 were reviewed. Adverse drug reactions with causal relationships were selected, and clinical manifestations, outcomes, and drug-related information were assessed. For further investigation, 8 years of pharmacovigilance data were collected at a single centre. Twenty-three patients participated in in vivo and in vitro studies. Skin tests, oral provocation tests, and laboratory tests were performed, including tests using other kinds of histamine H2 receptor antagonists. Over 7 years, 584 patients suffered adverse reactions to ranitidine. The most common manifestation was cutaneous symptoms. Among them, 99 patients (17.0%) experienced anaphylaxis. In a single-centre study, skin prick tests were positive in 91.7% of ranitidine-induced anaphylaxis patients (11/12); the optimal concentration was 20 mg/mL. Detection of ranitidine-specific immunoglobulin E failed. Cimetidine and proton pump inhibitors showed no cross-reactivity with ranitidine based on the skin prick test, oral provocation test, or clinical determination. Surprisingly, 82.6% of patients reintroduced ranitidine and re-experienced the same adverse reactions because ranitidine was not considered the culprit drug. Although ranitidine is known as a safe drug, it can also cause diverse adverse reactions, including anaphylaxis. This study demonstrates the need to pay attention to adverse reactions to ranitidine and consider ranitidine as a cause of anaphylaxis. © 2016 John Wiley & Sons Ltd.

  3. Factors associated with induced abortion among female entertainment workers: a cross-sectional study in Cambodia

    PubMed Central

    Yi, Siyan; Tuot, Sovannary; Chhoun, Pheak; Pal, Khuondyla; Tith, Khimuy; Brody, Carinne

    2015-01-01

    Objective To explore risk factors associated with induced abortion among sexually active female entertainment workers (FEWs) in Cambodia. Design Cross-sectional study. Setting Phnom Penh and Siem Reap, Cambodia. Participants This study included 556 FEWs aged 18–47 years randomly selected from entertainment establishments in the two cities in 2014 using a two-stage cluster sampling method. Data were collected through face-to-face interviews using a structured questionnaire. Primary outcome measure History of induced abortion during the time working as a FEW. Results Of the total sample, 45.6% reported currently using a contraceptive method with condom (42.4%) being the most common method, followed by pills (25.6%). One-fourth (25%) of the respondents reported having been pregnant at least once, and 21.4% reported having at least one induced abortion during the time working as a FEW. After controlling for other covariates in a multivariate logistic regression model, FEWs with a history of induced abortion remained significantly more likely to be currently working in a karaoke bar (AOR=1.75, 95% CI 1.10 to 2.78), to have worked longer as a FEW (AOR=1.42, 95% CI 1.06 to 1.43), to have had a greater number of sexual partners in the past 12 months (AOR=1.86, 95% CI 1.02 to 1.54), to be currently using a contraceptive method (AOR=1.52, 95% CI 1.01 to 2.29), to be able to find condoms when they needed them (AOR=2.03, 95% CI 1.09 to 3.82), and to report inconsistent condom use with non-commercial partners in the past 3 months (AOR=1.62, 95% CI 1.06 to 3.44). Conclusions This study highlights the high rates of unwanted pregnancies that ended in induced abortions among FEWs in Cambodia. Access of FEWs to quality sexual and reproductive healthcare services is deemed a high priority. Integrated interventions to improve sexual and reproductive health among these vulnerable women should be tailored to reach the most-at-risk groups. PMID:26231754

  4. Factors associated with induced abortion among female entertainment workers: a cross-sectional study in Cambodia.

    PubMed

    Yi, Siyan; Tuot, Sovannary; Chhoun, Pheak; Pal, Khuondyla; Tith, Khimuy; Brody, Carinne

    2015-07-31

    To explore risk factors associated with induced abortion among sexually active female entertainment workers (FEWs) in Cambodia. Cross-sectional study. Phnom Penh and Siem Reap, Cambodia. This study included 556 FEWs aged 18-47 years randomly selected from entertainment establishments in the two cities in 2014 using a two-stage cluster sampling method. Data were collected through face-to-face interviews using a structured questionnaire. History of induced abortion during the time working as a FEW. Of the total sample, 45.6% reported currently using a contraceptive method with condom (42.4%) being the most common method, followed by pills (25.6%). One-fourth (25%) of the respondents reported having been pregnant at least once, and 21.4% reported having at least one induced abortion during the time working as a FEW. After controlling for other covariates in a multivariate logistic regression model, FEWs with a history of induced abortion remained significantly more likely to be currently working in a karaoke bar (AOR=1.75, 95% CI 1.10 to 2.78), to have worked longer as a FEW (AOR=1.42, 95% CI 1.06 to 1.43), to have had a greater number of sexual partners in the past 12 months (AOR=1.86, 95% CI 1.02 to 1.54), to be currently using a contraceptive method (AOR=1.52, 95% CI 1.01 to 2.29), to be able to find condoms when they needed them (AOR=2.03, 95% CI 1.09 to 3.82), and to report inconsistent condom use with non-commercial partners in the past 3 months (AOR=1.62, 95% CI 1.06 to 3.44). This study highlights the high rates of unwanted pregnancies that ended in induced abortions among FEWs in Cambodia. Access of FEWs to quality sexual and reproductive healthcare services is deemed a high priority. Integrated interventions to improve sexual and reproductive health among these vulnerable women should be tailored to reach the most-at-risk groups. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go

  5. Dengue Virus Nonstructural Protein 1-Induced Antibodies Cross-React with Human Plasminogen and Enhance Its Activation.

    PubMed

    Chuang, Yung-Chun; Lin, Jessica; Lin, Yee-Shin; Wang, Shuying; Yeh, Trai-Ming

    2016-02-01

    Dengue virus (DENV) infection is the most common mosquito-borne viral disease, and it can cause life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Abnormal activation of the coagulation and fibrinolysis system is one of the hallmarks of DHF/DSS. However, the mechanism underlying hemorrhage in DHF/DSS remains elusive. In previous studies, plasminogen (Plg) cross-reactive Abs, which can recognize DENV nonstructural protein (NS) 1, have been found in dengue patients. However, it is unclear whether these Abs are indeed induced by DENV NS1. Thus, we immunized mice with recombinant NS1 from both bacteria and drosophila to determine whether NS1 can induce Plg cross-reactive Abs. The results from the NS1-immunized mouse sera indicated that NS1 immunization induced Abs that could cross-react with Plg. To study the effects of these NS1-induced Plg cross-reactive Abs on fibrinolysis, we isolated several Plg cross-reactive anti-NS1 mAbs from these mice and found that some of them could enhance Plg activation. In addition, epitope mapping with a phage-displayed random peptide library revealed that one of these mAbs (2A5) could recognize NS1 C-terminal residues 305-311, which share sequence homology with Plg residues 590-597. A synthetic peptide of NS1 residues 305-311 could inhibit the binding of both 2A5 and its Fab to Plg and its enhanced activation. Thus, our results suggest that DENV NS1 can induce Plg cross-reactive Abs through molecular mimicry, which can enhance Plg activation and may contribute to the pathogenesis of DHF/DSS.

  6. From Tucking to Twisting; A Case of Self-induced Testicular Torsion in a Cross Dressing Male.

    PubMed

    Epps, Thomas; McCormick, Barrett; Ali, Antar; Duboy, Alberto; Gillen, James; Martinez, Daniel; Carrion, Rafael

    2016-07-01

    A self-induced, non-traumatic testicular torsion is a rare entity that to our knowledge has not been reported in the literature. We report the case of a 28-year-old male who caused a self-induced testicular torsion during acts associated with cross dressing. Differential diagnosis of the acute scrotum in an adult should always include testicular torsion, as outcomes in this population are worse than in younger populations. Additional unusual causes of testicular torsion are reviewed.

  7. Laser Induced Optical Pumping Measurements of Cross Sections for Fine and Hyperfine Structure Transitions in Sodium Induced by Collisions with Helium Argon Atoms

    NASA Technical Reports Server (NTRS)

    Dobson, Chris C.; Sung, C. C.

    1998-01-01

    Optical pumping of the ground states of sodium can radically alter the shape of the laser induced fluorescence excitation spectrum, complicating measurements of temperature, pressure, etc., which are based on these spectra. Modeling of the fluorescence using rate equations for the eight hyperfine states of the sodium D manifolds can be used to quantify the contribution to the ground state pumping of transitions among the hyperfine excited states induced by collisions with buffer gas atoms. This model is used here to determine, from the shape of experimental spectra, cross sections for (Delta)F transitions of the P(sub 3/2) state induced by collisions with helium and argon atoms, for a range of values assumed for the P(sub 1/2), (Delta)F cross sections. The hyperfine cross sections measured using this method, which is thought to be novel, are compared with cross sections for transitions involving polarized magnetic substates, m(sub F), measured previously using polarization sensitive absorption. Also, fine structure transition ((Delta)J) cross sections were measured in the pumped vapor, giving agreement with previous measurements made in the absence of pumping.

  8. Laser-Induced Optical Pumping Measurements of Cross Section for Fine- and Hyperfine-Structure Transitions in Sodium Induced by Collisions with Helium and Argon Atoms

    NASA Technical Reports Server (NTRS)

    Dobson, Chris C.; Sung, C. C.

    1999-01-01

    Optical pumping of the ground states of sodium can radically alter the shape of the laser-induced fluorescence excitation spectrum, complicating measurements of temperature, pressure, etc., which are based on these spectra. Modeling of the fluorescence using rate equations for the eight hyperfine states of the sodium D manifolds can be used to quantify the contribution to the ground state pumping of transitions among the hyperfine excited states induced by collisions with buffer gas atoms. This model is used here to determine, from the shape of experimental spectra, cross sections lor DELTA.F transitions of the P(sub 3/2) state induced by collisions with helium and argon atoms, for a range of values assumed for the P(sub 1/2), DELTA.F cross sections. The hyperfine cross sections measured using this method, which to our knowledge is novel, are compared with cross sections for transitions involving polarized magnetic substates m(sub F) measured previously using polarization sensitive absorption. Also, fine-structure transition cross sections were measured in the pumped vapor, giving agreement with previous measurements made in the absence of pumping.

  9. Laser-Induced Optical Pumping Measurements of Cross Section for Fine- and Hyperfine-Structure Transitions in Sodium Induced by Collisions with Helium and Argon Atoms

    NASA Technical Reports Server (NTRS)

    Dobson, Chris C.; Sung, C. C.

    1999-01-01

    Optical pumping of the ground states of sodium can radically alter the shape of the laser-induced fluorescence excitation spectrum, complicating measurements of temperature, pressure, etc., which are based on these spectra. Modeling of the fluorescence using rate equations for the eight hyperfine states of the sodium D manifolds can be used to quantify the contribution to the ground state pumping of transitions among the hyperfine excited states induced by collisions with buffer gas atoms. This model is used here to determine, from the shape of experimental spectra, cross sections lor DELTA.F transitions of the P(sub 3/2) state induced by collisions with helium and argon atoms, for a range of values assumed for the P(sub 1/2), DELTA.F cross sections. The hyperfine cross sections measured using this method, which to our knowledge is novel, are compared with cross sections for transitions involving polarized magnetic substates m(sub F) measured previously using polarization sensitive absorption. Also, fine-structure transition cross sections were measured in the pumped vapor, giving agreement with previous measurements made in the absence of pumping.

  10. Vertical structure of cross-shore currents from wind-induced setup

    USGS Publications Warehouse

    Gelfenbaum, Guy

    1991-01-01

    Most of the storm surge models presented in the literature are vertically averaged and calculate only the sea-surface elevation and mean flow. Whereas these models may be adequate for predicting storm surge heights for flooding purposes, they neglect the vertical structure of the flow and the boundary shear stress, which are both critical for predicting cross-shore sediment transport. The steady and horizontally uniform equations of motion are used here to compute the sea-surface slope, the vertical structure of the cross-shore currents, and the boundary shear stress in a shallow wind dominated environment. The steady state model developed here balances the pressure gradient and the stress divergence, resulting in sea-surface slope and associated pressure gradient in the opposite direction of the wind, thus inducing a reversal in the currents near the bed. The Reynolds stress is modeled with a depth-dependent turbulent diffusion coefficient so that both the boundary shear stress and the velocity field are calculated, avoiding the need to set a bottom drag coefficient. Input parameters for this model are simply the wind stress, the water depth, and z0, the bed roughness parameter. A sensitivity test of the model results to various values of z0 indicates that large changes in z0 cause only minor differences in the surface slope, and moderate differences in the velocity field and boundary shear stress. Given the sediment size distribution and the small scale morphology of the bed, a reasonable estimate of z0 may be obtained and the above uncertainty will be nearly eliminated.

  11. Novel biomarkers of mercury-induced autoimmune dysfunction: a Cross-sectional study in Amazonian Brazil

    PubMed Central

    Motts, Jonathan A.; Shirley, Devon L.; Silbergeld, Ellen K.; Nyland, Jennifer F.

    2014-01-01

    Mercury is an ubiquitous environmental contaminant, causing both neurotoxicity and immunotoxicity. Given its ability to amalgamate gold, mercury is frequently used in small-scale artisanal gold mining. We have previously reported that elevated serum titers of antinuclear autoantibodies (ANA) are associated with mercury exposures of miners in gold mining. The goal of this project was to identify novel serum biomarkers of mercury-induced immunotoxicity and autoimmune dysregulation. We conducted an analysis of serum samples from a cross-sectional epidemiological study on miners working in Amazonian Brazil. In proteomic screening analyses, samples were stratified based on mercury concentrations and ANA titer and a subset of serum samples (N=12) were profiled using Immune Response Biomarker Profiling ProtoArray protein microarray for elevated autoantibodies. Of the up-regulated autoantibodies in the mercury-exposed cohort, potential target autoantibodies were selected based on relevance to pro-inflammatory and macrophage activation pathways. ELISAs were developed to test the entire sample cohort (N=371) for serum titers to the highest of these autoantibodies (anti-glutathione S-transferase alpha, GSTA1) identified in the high mercury/high ANA group. We found positive associations between elevated mercury exposure and up-regulated serum titers of 3760 autoantibodies as identified by ProtoArray. Autoantibodies identified as potential novel biomarkers of mercury-induced immunotoxicity include antibodies to the following proteins: GSTA1, tumor necrosis factor ligand superfamily member 13, linker for activation of T cells, signal peptide peptidase like 2B, stimulated by retinoic acid 13, and interferon induced transmembrane protein. ELISA analyses confirmed that mercury-exposed gold miners had significantly higher serum titers of anti-GSTA1 autoantibody [unadjusted odds ratio = 89.6; 95% confidence interval: 27.2, 294.6] compared to emerald miners (referent population

  12. Absolute cross-sections for DNA strand breaks and crosslinks induced by low energy electrons.

    PubMed

    Chen, Wenzhuang; Chen, Shiliang; Dong, Yanfang; Cloutier, Pierre; Zheng, Yi; Sanche, Léon

    2016-12-07

    Absolute cross sections (CSs) for the interaction of low energy electrons with condensed macromolecules are essential parameters to accurately model ionizing radiation induced reactions. To determine CSs for various conformational DNA damage induced by 2-20 eV electrons, we investigated the influence of the attenuation length (AL) and penetration factor (f) using a mathematical model. Solid films of supercoiled plasmid DNA with thicknesses of 10, 15 and 20 nm were irradiated with 4.6, 5.6, 9.6 and 14.6 eV electrons. DNA conformational changes were quantified by gel electrophoresis, and the respective yields were extrapolated from exposure-response curves. The absolute CS, AL and f values were generated by applying the model developed by Rezaee et al. The values of AL were found to lie between 11 and 16 nm with the maximum at 14.6 eV. The absolute CSs for the loss of the supercoiled (LS) configuration and production of crosslinks (CL), single strand breaks (SSB) and double strand breaks (DSB) induced by 4.6, 5.6, 9.6 and 14.6 eV electrons are obtained. The CSs for SSB are smaller, but similar to those for LS, indicating that SSB are the main conformational damage. The CSs for DSB and CL are about one order of magnitude smaller than those of LS and SSB. The value of f is found to be independent of electron energy, which allows extending the absolute CSs for these types of damage within the range 2-20 eV, from previous measurements of effective CSs. When comparison is possible, the absolute CSs are found to be in good agreement with those obtained from previous similar studies with double-stranded DNA. The high values of the absolute CSs of 4.6 and 9.6 eV provide quantitative evidence for the high efficiency of low energy electrons to induce DNA damage via the formation of transient anions.

  13. Triazole Fungicides Can Induce Cross-Resistance to Medical Triazoles in Aspergillus fumigatus

    PubMed Central

    Karawajczyk, Anna; Schaftenaar, Gijs; Kema, Gert H. J.; van der Lee, Henrich A.; Klaassen, Corné H.; Melchers, Willem J. G.; Verweij, Paul E.

    2012-01-01

    Background Azoles play an important role in the management of Aspergillus diseases. Azole resistance is an emerging global problem in Aspergillus fumigatus, and may develop through patient therapy. In addition, an environmental route of resistance development has been suggested through exposure to 14α-demethylase inhibitors (DMIs). The main resistance mechanism associated with this putative fungicide-driven route is a combination of alterations in the Cyp51A-gene (TR34/L98H). We investigated if TR34/L98H could have developed through exposure to DMIs. Methods and Findings Thirty-one compounds that have been authorized for use as fungicides, herbicides, herbicide safeners and plant growth regulators in the Netherlands between 1970 and 2005, were investigated for cross-resistance to medical triazoles. Furthermore, CYP51-protein homology modeling and molecule alignment studies were performed to identify similarity in molecule structure and docking modes. Five triazole DMIs, propiconazole, bromuconazole, tebuconazole, epoxiconazole and difenoconazole, showed very similar molecule structures to the medical triazoles and adopted similar poses while docking the protein. These DMIs also showed the greatest cross-resistance and, importantly, were authorized for use between 1990 and 1996, directly preceding the recovery of the first clinical TR34/L98H isolate in 1998. Through microsatellite genotyping of TR34/L98H isolates we were able to calculate that the first isolate would have arisen in 1997, confirming the results of the abovementioned experiments. Finally, we performed induction experiments to investigate if TR34/L98H could be induced under laboratory conditions. One isolate evolved from two copies of the tandem repeat to three, indicating that fungicide pressure can indeed result in these genomic changes. Conclusions Our findings support a fungicide-driven route of TR34/L98H development in A. fumigatus. Similar molecule structure characteristics of five triazole DMIs

  14. A structural basis for a phosphoramide mustard-induced DNA interstrand cross-link at 5'-d(GAC).

    PubMed Central

    Dong, Q; Barsky, D; Colvin, M E; Melius, C F; Ludeman, S M; Moravek, J F; Colvin, O M; Bigner, D D; Modrich, P; Friedman, H S

    1995-01-01

    Phosphoramide mustard-induced DNA interstrand cross-links were studied both in vitro and by computer simulation. The local determinants for the formation of phosphoramide mustard-induced DNA interstrand cross-links were defined by using different pairs of synthetic oligonucleotide duplexes, each of which contained a single potentially cross-linkable site. Phosphoramide mustard was found to cross-link dG to dG at a 5'-d(GAC)-3'. The structural basis for the formation of this 1,3 cross-link was studied by molecular dynamics and quantum chemistry. Molecular dynamics indicated that the geometrical proximity of the binding sites also favored a 1,3 dG-to-dG linkage over a 1,2 dG-to-dG linkage in a 5'-d(GCC)-3' sequence. While the enthalpies of 1,2 and 1,3 mustard cross-linked DNA were found to be very close, a 1,3 structure was more flexible and may therefore be in a considerably higher entropic state. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8618865

  15. Cytotoxic T cells are the predominant players providing cross-protective immunity induced by {gamma}-irradiated influenza A viruses.

    PubMed

    Furuya, Yoichi; Chan, Jennifer; Regner, Matthias; Lobigs, Mario; Koskinen, Aulikki; Kok, Tuckweng; Manavis, Jim; Li, Peng; Müllbacher, Arno; Alsharifi, Mohammed

    2010-05-01

    We previously demonstrated that a single dose of nonadjuvanted intranasal gamma-irradiated influenza A virus can provide robust protection in mice against both homologous and heterosubtypic challenges, including challenge with an H5N1 avian virus strain. We investigated the mechanism behind the observed cross-protection to define which arms of the adaptive immune response are involved in mediating this protection. Studies with gene knockout mice showed the cross-protective immunity to be mediated mainly by T cells and to be dependent on the cytolytic effector molecule perforin. Adoptive transfer of memory T cells from immunized mice, but not of memory B cells, protected naïve recipients against lethal heterosubtypic influenza virus challenge. Furthermore, gamma-irradiated influenza viruses induced cross-reactive Tc-cell responses but not cross-neutralizing or cross-protective antibodies. In addition, histological analysis showed reduced lung inflammation in vaccinated mice compared to that in unvaccinated controls following heterosubtypic challenge. This reduced inflammation was associated with enhanced early recruitment of T cells, both CD4(+) and CD8(+), and with early influenza virus-specific cytotoxic T-cell responses. Therefore, cross-protective immunity induced by vaccination with gamma-irradiated influenza A virus is mediated mainly by Tc-cell responses.

  16. Theoretical and experimental quantification of doubly and singly differential cross sections for electron-induced ionization of isolated tetrahydrofuran molecules

    SciTech Connect

    Champion, Christophe; Quinto, Michele A.; Bug, Marion U.; Baek, Woon Y.; Weck, Philippe F.

    2014-07-29

    Electron-induced ionization of the commonly used surrogate of the DNA sugar-phosphate backbone, namely, the tetrahydrofuran molecule, is here theoretically described within the 1st Born approximation by means of quantum-mechanical approach. Comparisons between theory and recent experiments are reported in terms of doubly and singly differential cross sections.

  17. On the thermally-induced residual stresses in thick fiber-thermoplastic matrix (PEEK) cross-ply laminated plates

    NASA Technical Reports Server (NTRS)

    Hu, Shoufeng; Nairn, John A.

    1992-01-01

    An analytical method for calculating thermally-induced residual stresses in laminated plates is applied to cross-ply PEEK laminates. We considered three cooling procedures: slow cooling (uniform temperature distribution); convective and radiative cooling; and rapid cooling by quenching (constant surface temperature). Some of the calculated stresses are of sufficient magnitude to effect failure properties such as matrix microcracking.

  18. Revised Calculations of the Production Rates for Co Isotopes in Meteorites Using New Cross Sections for Neutron-induced Reactions

    NASA Technical Reports Server (NTRS)

    Sisterson, J. M.; Brooks, F. D.; Buffler, A.; Allie, M. S.; Herbert, M. S.; Nchodu, M. R.; Makupula, S.; Ullmann, J.; Reedy, R. C.; Jones, D. T. L.

    2002-01-01

    New cross section measurements for reactions induced by neutrons with energies greater than 70 MeV are used to calculate the production rates for cobalt isotopes in meteorites and these new calculations are compared to previous estimates. Additional information is contained in the original extended abstract.

  19. Theoretical and experimental quantification of doubly and singly differential cross sections for electron-induced ionization of isolated tetrahydrofuran molecules

    DOE PAGES

    Champion, Christophe; Quinto, Michele A.; Bug, Marion U.; ...

    2014-07-29

    Electron-induced ionization of the commonly used surrogate of the DNA sugar-phosphate backbone, namely, the tetrahydrofuran molecule, is here theoretically described within the 1st Born approximation by means of quantum-mechanical approach. Comparisons between theory and recent experiments are reported in terms of doubly and singly differential cross sections.

  20. Revised Calculations of the Production Rates for Co Isotopes in Meteorites Using New Cross Sections for Neutron-induced Reactions

    NASA Technical Reports Server (NTRS)

    Sisterson, J. M.; Brooks, F. D.; Buffler, A.; Allie, M. S.; Herbert, M. S.; Nchodu, M. R.; Makupula, S.; Ullmann, J.; Reedy, R. C.; Jones, D. T. L.

    2002-01-01

    New cross section measurements for reactions induced by neutrons with energies greater than 70 MeV are used to calculate the production rates for cobalt isotopes in meteorites and these new calculations are compared to previous estimates. Additional information is contained in the original extended abstract.

  1. Revised Production Rates for Na-22 and Mn-54 in Meteorites Using Cross Sections Measured for Neutron-induced Reactions

    NASA Technical Reports Server (NTRS)

    Sisterson, J. M.; Kim, K. J.; Reedy, R. C.

    2004-01-01

    The interactions of galactic cosmic rays (GCR) with extraterrestrial bodies produce small amounts of radionuclides and stable isotopes. The production rates of many relatively short-lived radionuclides, including 2.6-year Na-22 and 312-day Mn-54, have been measured in several meteorites collected very soon after they fell. Theoretical models used to calculate production rates for comparison with the measured values rely on input data containing good cross section measurements for all relevant reactions. Most GCR particles are protons, but secondary neutrons make most cosmogenic nuclides. Calculated production rates using only cross sections for proton-induced reactions do not agree well with measurements. One possible explanation is that the contribution to the production rate from reactions initiated by secondary neutrons produced in primary GCR interactions should be included explicitly. This, however, is difficult to do because so few of the relevant cross sections for neutron-induced reactions have been measured.

  2. Revised Production Rates for Na-22 and Mn-54 in Meteorites Using Cross Sections Measured for Neutron-induced Reactions

    NASA Technical Reports Server (NTRS)

    Sisterson, J. M.; Kim, K. J.; Reedy, R. C.

    2004-01-01

    The interactions of galactic cosmic rays (GCR) with extraterrestrial bodies produce small amounts of radionuclides and stable isotopes. The production rates of many relatively short-lived radionuclides, including 2.6-year Na-22 and 312-day Mn-54, have been measured in several meteorites collected very soon after they fell. Theoretical models used to calculate production rates for comparison with the measured values rely on input data containing good cross section measurements for all relevant reactions. Most GCR particles are protons, but secondary neutrons make most cosmogenic nuclides. Calculated production rates using only cross sections for proton-induced reactions do not agree well with measurements. One possible explanation is that the contribution to the production rate from reactions initiated by secondary neutrons produced in primary GCR interactions should be included explicitly. This, however, is difficult to do because so few of the relevant cross sections for neutron-induced reactions have been measured.

  3. Molecular-scale dynamics of light-induced spin cross-over in a two-dimensional layer

    PubMed Central

    Bairagi, Kaushik; Iasco, Olga; Bellec, Amandine; Kartsev, Alexey; Li, Dongzhe; Lagoute, Jérôme; Chacon, Cyril; Girard, Yann; Rousset, Sylvie; Miserque, Frédéric; Dappe, Yannick J; Smogunov, Alexander; Barreteau, Cyrille; Boillot, Marie-Laure; Mallah, Talal; Repain, Vincent

    2016-01-01

    Spin cross-over molecules show the unique ability to switch between two spin states when submitted to external stimuli such as temperature, light or voltage. If controlled at the molecular scale, such switches would be of great interest for the development of genuine molecular devices in spintronics, sensing and for nanomechanics. Unfortunately, up to now, little is known on the behaviour of spin cross-over molecules organized in two dimensions and their ability to show cooperative transformation. Here we demonstrate that a combination of scanning tunnelling microscopy measurements and ab initio calculations allows discriminating unambiguously between both states by local vibrational spectroscopy. We also show that a single layer of spin cross-over molecules in contact with a metallic surface displays light-induced collective processes between two ordered mixed spin-state phases with two distinct timescale dynamics. These results open a way to molecular scale control of two-dimensional spin cross-over layers. PMID:27425776

  4. Study of activation cross-sections of deuteron induced reactions on rhodium up to 40 MeV

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.; Yamazaki, H.; Baba, M.; Mohammadi, A.; Ignatyuk, A. V.

    2011-09-01

    In the frame of a systematic study of the activation cross-sections of deuteron induced nuclear reactions, excitation functions of the 103Rh(d,x) 100,101,103Pd, 100g,101m,101g,102m,102gRh and 103gRu reactions were determined up to 40 MeV. Cross-sections were measured with the activation method using a stacked foil irradiation technique. Excitation functions of the contributing reactions were calculated using the ALICE-IPPE, EMPIRE-II and TALYS codes. From the measured cross-section data integral production yields were calculated and compared with experimental integral yield data reported in the literature. From the measured cross-sections and previous data, activation curves were deduced to support thin layer activation (TLA) on rhodium and Rh containing alloys.

  5. Evaluation of {sup 28,29,30}Si neutron induced cross sections for ENDF/B-VI

    SciTech Connect

    Hetrick, D.M.; Larson, D.C.; Larson, N.M.; Leal, L.C.; Epperson, S.J.

    1997-04-01

    Separate evaluations have been done for the three stable isotopes of silicon for ENDF/B-VI. The evaluations are based on analysis of experimental data, supplemented by results of nuclear model calculations. The computational methods and the parameters required as input to the nuclear model codes are reviewed. Discussion of the evaluated data given for resonance parameters, neutron induced reaction cross sections, associated angular and energy distributions, and gamma-ray production cross sections is included. Extensive comparisons of the evaluated cross sections to measured data are shown in this report. The evaluations include all necessary data to allow KERMA (Kinetic Energy Released in MAterials) and displacement cross sections to be calculated directly. These quantities are fundamental to studies of neutron heating and radiation damage.

  6. Measurements of Cross Sections for Neutron-induced Reactions on Chromium and Yttrium Targets at 197 MeV

    NASA Astrophysics Data System (ADS)

    Sekimoto, S.; Suzuki, H.; Yashima, H.; Ninomiya, K.; Kasamatsu, Y.; Shima, T.; Takahashi, N.; Shinohara, A.; Matsumura, H.; Hagiwara, M.; Nishiizumi, K.; Caffee, M. W.; Shibata, S.

    2014-05-01

    Reaction cross sections for Cr and Y induced by neutrons at 197 MeV were measured by using 7Li(p,n) reaction at N0 beam line in the Research Center for Nuclear Physics (RCNP), Osaka University. To estimate quasi-monoenergetic neutron cross sections, Cr and Y samples were irradiated on the two angles of 0∘ and 25∘ relative to the axis of the primary proton beam. The measured cross section data in the natCr(n,x) and 89Y(n,x) reactions are compared to the JENDL high-energy file and the literature proton values, respectively. The results obtained are also compared to the cross section data for the same target materials with 287 and 386 MeV neutrons in our previous work.

  7. Access, equity and costs of induced abortion services in Australia: a cross-sectional study.

    PubMed

    Shankar, Mridula; Black, Kirsten I; Goldstone, Philip; Hussainy, Safeera; Mazza, Danielle; Petersen, Kerry; Lucke, Jayne; Taft, Angela

    2017-06-01

    To examine access and equity to induced abortion services in Australia, including factors associated with presenting beyond nine weeks gestation. Cross-sectional survey of 2,326 women aged 16+ years attending for an abortion at 14 Dr Marie clinics. Associations with later presentation assessed using multivariate logistic regression. Over a third of eligible women opted for a medical abortion. More than one in 10 (11.2%) stayed overnight. The median Medicare rebated upfront cost of a medical abortion was $560, compared to $470 for a surgical abortion at ≤9 weeks. Beyond 12 weeks, costs rose considerably. More than two-thirds (68.1%) received financial assistance from one or more sources. Women who travelled ≥4 hours (AdjOR: 3.0, 95%CI 1.2-7.3), had no prior knowledge of the medical option (AdjOR: 2.1, 95%CI 1.4-3.1), had difficulty paying (AdjOR: 1.5, 95%CI 1.2-1.9) and identified as Aboriginal and/or Torres Strait Islander (AdjOR: 2.1, 95%CI 1.2-3.4) were more likely to present ≥9 weeks. Abortion costs are substantial, increase at later gestations, and are a financial strain for many women. Poor knowledge, geographical and financial barriers restrict method choice. Implications for public health: Policy reform should focus on reducing costs and enhancing early access. © 2017 The Authors.

  8. Molecular motor-induced instabilities and cross linkers determine biopolymer organization.

    SciTech Connect

    Smith, D.; Ziebert, F.; Humphrey, D.; Duggan, C.; Steinbeck, M.; Zimmermann, W.; Kas, J.; Materials Science Division; Univ. of Leipzig; Univ. of Texas at Austin; Univ. Bayreuth

    2007-01-01

    All eukaryotic cells rely on the active self-organization of protein filaments to form a responsive intracellular cytoskeleton. The necessity of motility and reaction to stimuli additionally requires pathways that quickly and reversibly change cytoskeletal organization. While thermally driven order-disorder transitions are, from the viewpoint of physics, the most obvious method for controlling states of organization, the timescales necessary for effective cellular dynamics would require temperatures exceeding the physiologically viable temperature range. We report a mechanism whereby the molecular motor myosin II can cause near-instantaneous order-disorder transitions in reconstituted cytoskeletal actin solutions. When motor-induced filament sliding diminishes, the actin network structure rapidly and reversibly self-organizes into various assemblies. Addition of stable cross linkers was found to alter the architectures of ordered assemblies. These isothermal transitions between dynamic disorder and self-assembled ordered states illustrate that the interplay between passive crosslinking and molecular motor activity plays a substantial role in dynamic cellular organization.

  9. Laser-induced fluorescence diagnostics of the cross-field discharge of Hall thrusters

    NASA Astrophysics Data System (ADS)

    Mazouffre, Stéphane

    2013-02-01

    This article presents a review of work performed over the past ten years in France, centered on the utilization of laser-induced fluorescence (LIF) spectroscopy to diagnose the low-pressure magnetized dc discharge of a Hall thruster (HT). The latter is a gridless electric propulsion device in a crossed electric and magnetic field configuration, which is used onboard satellites and space probes for various types of maneuvers. Although the design of a HT is relatively simple, the physical mechanisms that govern thrust generation and efficiency are not yet fully understood. Characterization of the ion and atom velocity distribution function (VDF) appears to be a powerful way to obtain insights into the underlying physics. The VDF of xenon and krypton—the most common propellants—is therefore locally interrogated by means of LIF on excited levels. In this review emphasis is placed on time-averaged and time-resolved continuous-wave LIF measurements, associated quantities and recent outcomes. Results will be presented concerning a variety of phenomena: velocity vector field structuring, ion population interaction, electric field generation, ion magnetic drift, apparent atom acceleration, interaction of the plasma plume with background gas and low-frequency electric field oscillations, to name only a few.

  10. RNA-protein cross-links induced by sensitization with a pyrroloquinolinone derivative, a furocoumarin analogue.

    PubMed

    Baccichetti, F; Marzano, C; Carlassare, F; Guiotto, A; Bordin, F

    1997-10-01

    The capacity of 2,6-dimethyl-9-methoxy-4H-pyrrolo [3,2,1-ij] quinolin-4-one (PQ), a furocoumarin analogue, of inhibiting protein synthesis in Ehrlich cells upon UVA irradiation was investigated. Using 8-methoxypsoralen (8-MOP) as a reference, we observed that in our short-term test the block of RNA synthesis do not affect protein synthesis, which is driven by pre-synthesised molecules of m-RNA; actually 8-MOP, studied at 100 microM concentration, practically abolished RNA synthesis without affecting significantly protein synthesis. Studying PQ sensitization in HL60 cells by alkaline elution and protein precipitation, the formation of covalent RNA-protein cross-links was observed. 8-MOP, assayed in severe experimental conditions, induced only moderate amounts of such lesion. On the basis of the data obtained in experiments carried out using various scavengers or exposing cells to UVA light in a nitrogen atmosphere, this damage appeared to be due to singlet oxygen formation, which is generated by PQ to a large extent. These results are consistent with the data obtained by H. Singh and J.A. Vadasz (Singlet oxygen: a major reactive species in the furocoumarin photosensitized inactivation of E.coli ribosomes, Photochem. Photobiol., 28 (1978) 539-545) on E.coli ribosomes. The lower activity we observed with 8-MOP might be attributed to a different sensitivity of whole mammalian cells in comparison with isolated ribosomes.

  11. Three-body collision contributions to recombination and collision-induced dissociation. 1: Cross sections

    SciTech Connect

    Pack, R.T.; Walker, R.B.; Kendrick, B.K.

    1998-04-10

    Atomic and molecular recombination and collision-induced dissociation (CID) reactions comprise two of the most fundamental types of chemical reactions. They are important in all gas phase chemistry; for example, about half of the 196 reactions identified as important in combustion chemistry are recombination or CID reactions. Many of the current chemical kinetics textbooks and kinetics papers treat atomic and molecular recombination and CID as occurring only via sequences of two-body collisions. Actually, there is considerable evidence from experiment and classical trajectory calculations for contributions by true three-body collisions to the recombination of atomic and diatomic radicals, and that evidence is reviewed. Then, an approximate quantum method treating both two-body and three-body collisions simultaneously and on equal footing is used to calculate cross sections for the reaction Ne{sub 2} + H {rightleftharpoons} Ne + Ne + H. The results provide clear quantum evidence that direct three-body collisions do contribute significantly to recombination and CID.

  12. Molecular Motor-Induced Instabilities and Cross Linkers Determine Biopolymer Organization

    PubMed Central

    Smith, D.; Ziebert, F.; Humphrey, D.; Duggan, C.; Steinbeck, M.; Zimmermann, W.; Käs, J.

    2007-01-01

    All eukaryotic cells rely on the active self-organization of protein filaments to form a responsive intracellular cytoskeleton. The necessity of motility and reaction to stimuli additionally requires pathways that quickly and reversibly change cytoskeletal organization. While thermally driven order-disorder transitions are, from the viewpoint of physics, the most obvious method for controlling states of organization, the timescales necessary for effective cellular dynamics would require temperatures exceeding the physiologically viable temperature range. We report a mechanism whereby the molecular motor myosin II can cause near-instantaneous order-disorder transitions in reconstituted cytoskeletal actin solutions. When motor-induced filament sliding diminishes, the actin network structure rapidly and reversibly self-organizes into various assemblies. Addition of stable cross linkers was found to alter the architectures of ordered assemblies. These isothermal transitions between dynamic disorder and self-assembled ordered states illustrate that the interplay between passive crosslinking and molecular motor activity plays a substantial role in dynamic cellular organization. PMID:17604319

  13. Pressure-induced crossing of the core levels in 5 d metals

    NASA Astrophysics Data System (ADS)

    Tal, Alexey A.; Katsnelson, Mikhail I.; Ekholm, Marcus; Jönsson, H. Johan M.; Dubrovinsky, Leonid; Dubrovinskaia, Natalia; Abrikosov, Igor A.

    2016-05-01

    A pressure-induced interaction between core electrons, the core-level crossing (CLC) transition, has been observed in hcp Os at P ≈400 GPa [L. Dubrovinsky et al., Nature (London) 525, 226 (2015)], 10.1038/nature14681. By carrying out a systematic theoretical study for all metals of the 5 d series (Hf, Ta, W, Re, Os, Ir, Pt, Au) we have found that the CLC transition is a general effect for this series of metals. While in Pt it occurs at ≈1500 GPa , at a pressure substantially higher than in Os, in Ir it occurs already at 80 GPa. Moreover, we predict that in Re the CLC transition may take place already at ambient pressure. We explain the effect of the CLC and analyze the shift of the transition pressure across the series within the Thomas-Fermi model. In particular, we show that the effect has many common features with the atomic collapse in rare-earth elements.

  14. Relationship between cross-linking conditions of ethylene vinyl acetate and potential induced degradation for crystalline silicon photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Jonai, Sachiko; Hara, Kohjiro; Tsutsui, Yuji; Nakahama, Hidenari; Masuda, Atsushi

    2015-08-01

    In this study, we investigated the relationship in crystalline silicon (c-Si) photovoltaic (PV) modules between the cross-linking level of copolymer of ethylene and vinyl acetate (EVA) as the encapsulant and the degree of degradation due to potential induced degradation (PID) phenomenon. We used three methods for the determination of cross-linking level of EVA: xylene method, which is one of the solvent extraction methods (SEM), curing degree by differential scanning calorimetry (DSC), and viscoelastic properties by dynamic mechanical analysis (DMA). The results indicate that degradation of PV modules by PID test depends on the cross-linking level of EVA. The PV modules encapsulated by EVA with higher cross-linking level show lower degradation degree due to PID phenomenon. Also we showed that EVA with higher cross-linking level tended to be higher volume resistivity. This tendency is similar to that for electrical resistance value during the PID test. The PID test was also done by changing thickness of EVA between front cover glass and c-Si with the same cross-linking level. The PV modules encapsulated by thicker EVA between front cover glass and c-Si cell show lower degradation by PID. From these results, the PV modules encapsulated by EVA with higher cross-linking level, higher volume resistivity and increased thickness would be tolerant of PID phenomenon.

  15. Double strand-breaks and DNA-to-protein cross-links induced by fast neutrons in bacteriophage DNA.

    PubMed

    Hawkins, R B

    1979-01-01

    Coliphage T7 was suspended in tryptone broth and exposed to a mixture of fast neutrons and gamma radiation. Plaque survival, double strand-breaks and DNA-to-protein cross-linkage were examined and the results compared with those found in phage exposed to gamma radiation alone. Neutral sucrose density sedimentation patterns indicate that neutron-induced double strand-breaks sometimes occur in clusters of more than 100 in the same phage and that the effeciency with which double strand-breaks form is about 50 times that of gamma-induced double strand-breaks. Neutron-induced protein-to-DNA cross-links probably also occur in clusters with enhanced efficiency relative to low LET radiation.

  16. Evaluation of Cross-Section Sensitivities in Computing Burnup Credit Fission Product Concentrations

    SciTech Connect

    Gauld, I.C.

    2005-08-12

    U.S. Nuclear Regulatory Commission Interim Staff Guidance 8 (ISG-8) for burnup credit covers actinides only, a position based primarily on the lack of definitive critical experiments and adequate radiochemical assay data that can be used to quantify the uncertainty associated with fission product credit. The accuracy of fission product neutron cross sections is paramount to the accuracy of criticality analyses that credit fission products in two respects: (1) the microscopic cross sections determine the reactivity worth of the fission products in spent fuel and (2) the cross sections determine the reaction rates during irradiation and thus influence the accuracy of predicted final concentrations of the fission products in the spent fuel. This report evaluates and quantifies the importance of the fission product cross sections in predicting concentrations of fission products proposed for use in burnup credit. The study includes an assessment of the major fission products in burnup credit and their production precursors. Finally, the cross-section importances, or sensitivities, are combined with the importance of each major fission product to the system eigenvalue (k{sub eff}) to determine the net importance of cross sections to k{sub eff}. The importances established the following fission products, listed in descending order of priority, that are most likely to benefit burnup credit when their cross-section uncertainties are reduced: {sup 151}Sm, {sup 103}Rh, {sup 155}Eu, {sup 150}Sm, {sup 152}Sm, {sup 153}Eu, {sup 154}Eu, and {sup 143}Nd.

  17. Enterovirus infection can induce immune responses that cross-react with beta-cell autoantigen tyrosine phosphatase IA-2/IAR.

    PubMed

    Härkönen, T; Lankinen, H; Davydova, B; Hovi, T; Roivainen, M

    2002-03-01

    Insulin-dependent (type 1) diabetes is characterized by progressive destruction of insulin-producing beta cells probably by autoreactive T lymphocytes. Viral infections, especially those caused by coxsackieviruses, are postulated to play a role in the pathogenesis of the disease in humans. One mechanism by which viral infections could initiate or accelerate diabetogenic processes is "molecular mimicry," induction of antiviral immune responses cross-reacting with epitopes in the beta-cell autoantigens. Tyrosine phosphatases (IA-2, IAR) represent a major target autoantigen in type 1 diabetes. Both humoral and cellular immune responses are directed to the carboxy-terminal (C-terminal) part of the protein. This region has a 5-amino acid sequence identity, followed by five amino acid similarity with the conservative motif in the VP1-protein of enteroviruses (PALTAVETGA/HT), which is a highly immunogenic B- and T-cell epitope in enterovirus infection-induced immune responses. This observation prompted us to investigate potential humoral cross-reactions between immune responses induced by tyrosine phosphatases and enteroviruses. The reactivities of various peptide- and virus-induced rabbit antisera clearly demonstrated that cross-reactions do exist, and in both directions. Using epitope mapping, we were able to show that several diabetes-linked epitopes in IA-2 were also recognized by CBV-4-induced antisera. Immunization of female NOD-mice with formalin-inactivated purified strain of coxsackievirus B4 (CBV-4-E2) induced an immune response that recognized the IA-2/IAR diabetogenic peptide. The results obtained with human paired sera, collected during enterovirus infection, indicated that enterovirus infection in humans may also occasionally induce a humoral response that cross-reacts with IA-2/IAR. Copyright 2002 Wiley-Liss, Inc.

  18. Electrically driven biofouling release of a poly(tetrafluoroethylene) membrane modified with an electrically induced reversibly cross-linked polymer.

    PubMed

    Chuo, Tsai-Wei; Wei, Ta-Chin; Chang, Yung; Liu, Ying-Ling

    2013-10-23

    Electrically induced reversible reactions between ferrocene (Fc) and β-cyclodextrin (β-CD) groups have been utilized for preparation of poly(tetrafluoroethylene) (PTFE) membranes exhibiting electrically driven biofouling release properties. PTFE membrane is surface-modified with polymer chains possessing Fc pendant groups. The surface layer is then cross-linked with a difunctional β-CD compound by means of the Fc/β-CD complexation reaction. The electrically induced reversibly cross-linking and de-cross-linking behaviors of the surface layer of the modified PTFE membrane have been characterized with Fourier transform Infrared, X-ray photoelectron spectroscopy, and scanning electron microscopy. The surface-modified PTFE membrane has been fouled with protein absorption. Electrical treatment of the fouled membrane results in a protein detachment from the membrane surface driven by the surface structure change accompanied with the electrically induced de-cross-linking reaction of the Fc/β-CD linkages. A smart membrane exhibiting a novel cleaning technology for membrane fouling has been developed.

  19. Genetic control of excision of Saccharomyces cerevisiae interstrand DNA cross-links induced by psoralen plus near-UV light

    SciTech Connect

    Miller, R.D.; Prakash, L.; Prakash, S.

    1982-08-01

    Excision of interstrand DNA cross-links induced by 4,5',8-trimethyl psoralen plus 360-nm light was examined in wild type (RAD+) and various radiation-sensitive (rad) mutants of Saccharomyces cerevisiae known to be defective in the excision of UV light-induced pyrimidine dimers. Alkaline sucrose sedimentation of DNA after incubation of psoralen-plus-light-treated cells indicated little or no nicking of cross-linked DNA in rad1-2, rad2-5, rad3-2, rad4-4, rad10-2, and mms19-1 mutants. In the rad14-2 mutant, substantial nicking was observed but to a much lesser extent than in the RAD+ strains, whereas the rad16-1 mutant was as proficient in nicking as the RAD+ strain. Removal of cross-links was also examined in RAD+, rad3-2, and rad14-2 strains by determining the sensitivity of alkali-denatured and -neutralized DNA to hydrolysis by S1 nuclease. No cross-link removal was observed in the rad3-2 mutants, and the rad14-2 mutant was much less efficient than the RAD+ strain in removing cross-links.

  20. Comparative studies on performance of radiation-induced and thermal cross-linked ion-exchange membrane for water electrolysis

    NASA Astrophysics Data System (ADS)

    Chakrabarty, Tina; Jasti, Amaranadh; Goel, N. K.; Shahi, Vinod K.; Sabharwal, Sunil

    2011-07-01

    Radiation-induced and thermal cross-linked sulfonated poly(ether sulfone) (SPS)-sulfonated poly(ether ether ketone) (SPK) composite ion-exchange membranes (SPS/SPK(γ) and SPS/SPK(T), respectively) were prepared. Their performances for water electrolysis were comparatively assessed. Thermal cross-linked membrane (SPS/SPK(T)) showed cross-linking of part functional groups (-SO 3H) and thus deterioration in membrane conductivity. While, radiation-induced cross-linked membrane (SPS/SPK(γ)) avoided any cross-linking between functional groups and thus conductivity. Electrolysis performances of these membranes were evaluated in comparison with Nafion117 membrane. Relatively low current efficiency (CE) for SPS/SPK and SPS/SPK(T) membranes was due to their high mass transfer (water) via electro-osmotic drag, which was negligible for SPS/SPK(γ) membrane. SPS/SPK(γ) membrane exhibited comparable stabilities and water splitting performance with Nafion117 membrane, which revealed its suitability as substitute for electrochemical applications.

  1. Sex steroid dependency of diabetes-induced changes in polyol metabolism, vascular permeability, and collagen cross-linking.

    PubMed

    Williamson, J R; Rowold, E; Chang, K; Marvel, J; Tomlinson, M; Sherman, W R; Ackermann, K E; Berger, R A; Kilo, C

    1986-01-01

    The effects of castration on diabetes-induced increases in collagen cross-linking and vascular permeability and on polyol levels in new granulation tissue formed after induction of streptozocin (STZ) diabetes were examined in male Sprague-Dawley rats. New granulation tissue formation was induced by implanting sterile polyester fabric subcutaneously (s.c.) at the time of STZ injection 3 wk before assessment of vascular permeability and collagen cross-linking. Castration was performed 10 days before implanting the fabric. The characteristic increases in collagen cross-linking (manifested by decreased solubility in 0.5 M acetic acid) and in albumin permeation of the vasculature seen in intact diabetic rats were completely prevented by castration. Net collagen accumulation was not affected by diabetes or castration. Castration also markedly diminished diabetes-induced increases in tissue levels of sorbitol and completely prevented the decreases in tissue levels of myo-inositol and scyllo-inositol observed in intact diabetic rats, but had no effect on serum glucose levels, nonenzymatic glycosylation of plasma and granulation tissue proteins, or plasma somatomedin-C levels. The demonstration that castration prevents diabetes-induced increases in vascular permeability and collagen cross-linking as well as imbalances in tissue levels of sorbitol, myo-inositol, and scyllo-inositol in this model indicates that all of these changes are sex steroid-dependent phenomena. While the pathogenesis of these vascular permeability and collagen cross-linking changes is clearly multifactorial, these new findings: indicate that the role of sex steroids in the development of late complications of diabetes may be far more important than hitherto suspected, and suggest an explanation for the clinical observation that diabetic complications are uncommon in prepubertal diabetic subjects regardless of duration of diabetes.

  2. The heptide repeat 2 and upstream region of TGEV induces potent cross-neutralizing antibodies against group I coronaviruses.

    PubMed

    Shi, Huiling; Wu, Nannan; Wang, Xiaoming; Wang, Tianhou

    2012-10-01

    The coronavirus heptide repeat (HR) region in the spike protein induces neutralizing antibodies that block the postfusion core formation and inhibit virus entry into target cells. The HR2 regions for coronaviruses of the same serogroup share high homology. We found that polyclonal antibodies derived from transmissible gastroenteritis coronavirus HR2 and upstream region were cross-reactive with the S proteins of the same serogroup in western blotting. The polyclonal antibodies also potently cross-neutralized viruses from the same serogroup. This study provides new insight for designing vaccine and therapeutic reagents against coronavirus infections.

  3. Study of Neutron-Induced Fission Cross Sections of U, Am, and Cm at n_TOF

    NASA Astrophysics Data System (ADS)

    Milazzo, P. M.; Abbondanno, U.; Aerts, G.; Alvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Becčvář, F.; Belloni, F.; Berthoumieux, E.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillman, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; Gonzalez-Romero, E.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Heil, M.; Herrera-Martinez, A.; Jericha, E.; Käppeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martinez, T.; Massimi, C.; Mastinu, P.; Mengoni, A.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Reifarth, R.; Rubbia, C.; Rudolf, G.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K.

    2010-08-01

    Neutron induced fission cross sections of several isotopes have been measured at the CERN n_TOF spallation neutron facility. Between them some measurements involve isotopes (233U, 241Am, 243Am, 245Cm) relevant for applications to nuclear technologies. The n_TOF facility delivers neutrons with high instantaneous flux and in a wide energy range, from thermal up to 250 MeV. The experimental apparatus consists of an ionization chamber that discriminates fission fragments and α particles coming from natural radioactivity of the samples. All the measurements were performed referring to the standard cross section of 235U.

  4. Cross-Diffusion Induced Turing Instability and Amplitude Equation for a Toxic-Phytoplankton-Zooplankton Model with Nonmonotonic Functional Response

    NASA Astrophysics Data System (ADS)

    Han, Renji; Dai, Binxiang

    2017-06-01

    The spatiotemporal pattern induced by cross-diffusion of a toxic-phytoplankton-zooplankton model with nonmonotonic functional response is investigated in this paper. The linear stability analysis shows that cross-diffusion is the key mechanism for the formation of spatial patterns. By taking cross-diffusion rate as bifurcation parameter, we derive amplitude equations near the Turing bifurcation point for the excited modes in the framework of a weakly nonlinear theory, and the stability analysis of the amplitude equations interprets the structural transitions and stability of various forms of Turing patterns. Furthermore, we illustrate the theoretical results via numerical simulations. It is shown that the spatiotemporal distribution of the plankton is homogeneous in the absence of cross-diffusion. However, when the cross-diffusivity is greater than the critical value, the spatiotemporal distribution of all the plankton species becomes inhomogeneous in spaces and results in different kinds of patterns: spot, stripe, and the mixture of spot and stripe patterns depending on the cross-diffusivity. Simultaneously, the impact of toxin-producing rate of toxic-phytoplankton (TPP) species and natural death rate of zooplankton species on pattern selection is also explored.

  5. CPR-induced consciousness: A cross-sectional study of healthcare practitioners' experience.

    PubMed

    Olaussen, Alexander; Shepherd, Matthew; Nehme, Ziad; Smith, Karen; Jennings, Paul A; Bernard, Stephen; Mitra, Biswadev

    2016-11-01

    Consciousness may occur during effective management of cardiac arrest and ranges from eye opening to interfering with rescuers' resuscitation attempts. Reported cases in the medical literature appear scant compared to anecdotal reports. The aim of this study was to evaluate health care providers' experience with consciousness during cardio-pulmonary resuscitation (CPR). A cross-sectional survey of 100 experienced health care professionals, including doctors, nurses and paramedics. Participants were asked about their experience with both CPR-non-interfering consciousness (e.g. eye opening, agonal breaths or mild restlessness) and CPR-interfering consciousness (e.g. purposeful movement, withdrawing from CPR, attempting to pull out airway-securing devices). A third of responders reported attending more than 100 cases of arrests, while another third had attended 20 or less arrests. The responders had a mean of 11 (SD 8.7) years of practice. Most responders (59 of 67) to the question had experienced CPR-non-interfering consciousness and reported experiencing it a median of 3 (IQR 1-5) times. CPR-interfering consciousness had been experienced by 51 of the 63 responders and was experienced overall 1 (IQR 1-3) time. Management of these cases varied widely with varied opinion on ideal management ranging from no action to sedation and/or paralysis. A guideline describing the management of this presentation was considered necessary by 40 out of 57 (70%) responders. Contrasting to a few reports in the medical literature, CPR-induced consciousness appears to be experienced more commonly during resuscitation. Management strategies varied widely and clinician opinion of ideal management was also varied. The desire for consensus guidelines on this topic exists. Acute care nurses are integral members of all resuscitation teams and in conjunction with other clinicians, ideally placed to develop, implement and disseminate such guidelines to delivering evidence based care to this sub

  6. Cross-talk between Akkermansia muciniphila and intestinal epithelium controls diet-induced obesity.

    PubMed

    Everard, Amandine; Belzer, Clara; Geurts, Lucie; Ouwerkerk, Janneke P; Druart, Céline; Bindels, Laure B; Guiot, Yves; Derrien, Muriel; Muccioli, Giulio G; Delzenne, Nathalie M; de Vos, Willem M; Cani, Patrice D

    2013-05-28

    Obesity and type 2 diabetes are characterized by altered gut microbiota, inflammation, and gut barrier disruption. Microbial composition and the mechanisms of interaction with the host that affect gut barrier function during obesity and type 2 diabetes have not been elucidated. We recently isolated Akkermansia muciniphila, which is a mucin-degrading bacterium that resides in the mucus layer. The presence of this bacterium inversely correlates with body weight in rodents and humans. However, the precise physiological roles played by this bacterium during obesity and metabolic disorders are unknown. This study demonstrated that the abundance of A. muciniphila decreased in obese and type 2 diabetic mice. We also observed that prebiotic feeding normalized A. muciniphila abundance, which correlated with an improved metabolic profile. In addition, we demonstrated that A. muciniphila treatment reversed high-fat diet-induced metabolic disorders, including fat-mass gain, metabolic endotoxemia, adipose tissue inflammation, and insulin resistance. A. muciniphila administration increased the intestinal levels of endocannabinoids that control inflammation, the gut barrier, and gut peptide secretion. Finally, we demonstrated that all these effects required viable A. muciniphila because treatment with heat-killed cells did not improve the metabolic profile or the mucus layer thickness. In summary, this study provides substantial insight into the intricate mechanisms of bacterial (i.e., A. muciniphila) regulation of the cross-talk between the host and gut microbiota. These results also provide a rationale for the development of a treatment that uses this human mucus colonizer for the prevention or treatment of obesity and its associated metabolic disorders.

  7. Cross-talk between Akkermansia muciniphila and intestinal epithelium controls diet-induced obesity

    PubMed Central

    Everard, Amandine; Belzer, Clara; Geurts, Lucie; Ouwerkerk, Janneke P.; Druart, Céline; Bindels, Laure B.; Guiot, Yves; Derrien, Muriel; Muccioli, Giulio G.; Delzenne, Nathalie M.; de Vos, Willem M.; Cani, Patrice D.

    2013-01-01

    Obesity and type 2 diabetes are characterized by altered gut microbiota, inflammation, and gut barrier disruption. Microbial composition and the mechanisms of interaction with the host that affect gut barrier function during obesity and type 2 diabetes have not been elucidated. We recently isolated Akkermansia muciniphila, which is a mucin-degrading bacterium that resides in the mucus layer. The presence of this bacterium inversely correlates with body weight in rodents and humans. However, the precise physiological roles played by this bacterium during obesity and metabolic disorders are unknown. This study demonstrated that the abundance of A. muciniphila decreased in obese and type 2 diabetic mice. We also observed that prebiotic feeding normalized A. muciniphila abundance, which correlated with an improved metabolic profile. In addition, we demonstrated that A. muciniphila treatment reversed high-fat diet-induced metabolic disorders, including fat-mass gain, metabolic endotoxemia, adipose tissue inflammation, and insulin resistance. A. muciniphila administration increased the intestinal levels of endocannabinoids that control inflammation, the gut barrier, and gut peptide secretion. Finally, we demonstrated that all these effects required viable A. muciniphila because treatment with heat-killed cells did not improve the metabolic profile or the mucus layer thickness. In summary, this study provides substantial insight into the intricate mechanisms of bacterial (i.e., A. muciniphila) regulation of the cross-talk between the host and gut microbiota. These results also provide a rationale for the development of a treatment that uses this human mucus colonizer for the prevention or treatment of obesity and its associated metabolic disorders. PMID:23671105

  8. Challenges for Induced Polarization Measurements in Single and Cross Borehole Configurations

    NASA Astrophysics Data System (ADS)

    Ntarlagiannis, D.; Slater, L. D.; Curatola, F.; Evdokimov, K.

    2013-12-01

    Induced polarization (IP) surveys have been traditionally used for mineral exploration. These surveys involve large surface arrays, cover wide areas and target strong signals from metallic minerals (e.g. sulfides). In recent years, the IP method has increasingly been used for environmental applications where smaller arrays are employed to measure smaller signals. Due to its unique sensitivity to interfacial properties, the IP method might be used to track and identify processes associated with remediation efforts, and also characterize and delineate contaminant plumes. Recent laboratory experiments have significantly advanced the IP method, improving the detection and interpretation of relatively small signals. However, IP data acquisition from a borehole, either as a vertical profile down a string of electrodes installed in a well or in a cross borehole configuration is more challenging. This is in part due to higher noise levels associated with coupling effects between wiring and earth in the borehole. In this study, we simulated borehole conditions in the laboratory and examined sources of noise during borehole IP measurements. We simulated a vertical array of electrodes, with electrodes placed around a PVC pipe, and performed measurements in a 3D tank. While in traditional single borehole configurations (e.g. Wenner, Schlumberger) the IP data were contaminated with low frequency errors associated with electrode arrangement. Modifications on the electrode configurations and the potential electrode design, led to acquisition of high quality data comparable to that obtained in the laboratory. We show that, while borehole IP measurements can be challenging, appropriate consideration of electrode placement and design permits acquisition of high quality data that can be used to sense variations in interfacial properties around a borehole.

  9. Flow-induced oscillations of a prism with triangular cross-section placed in water

    NASA Astrophysics Data System (ADS)

    Carlson, Daniel; Seyed-Aghazadeh, Banafsheh; Modarres-Sadeghi, Yahya

    2015-11-01

    Flow-induced oscillations of a prism with a triangular cross-section was studied experimentally. The cylinder had one-degree-of-freedom to oscillate in the crossflow direction. The response of the cylinder in terms of the amplitudes of oscillations as well as the flow forces were studied at varying angles of attack in the range of α = 0° -60° and a reduced velocity range of U* =4-22. Depending on the angle of attack and the reduced velocity, the cylinder experienced either VIV or galloping. For small angles of attack of α<30°, the cylinder did not oscillate while for larger angles of α = 30° and 35°, the cylinder underwent VIV in a range of reduced velocities (U* =7-14.5) and galloping at higher reduced velocities (U* =19.5-22). The conducted dye flow visualization as well as the measured flow forces confirmed the existence of lock-in as well as galloping-type response. For larger angles of attack of α>35°, the amplitude of oscillations increased monotonically with increasing reduced velocity and the cylinder underwent galloping. Several different vortex shedding patterns were observed in the wake of the cylinder at different angles of attack and flow velocities. New, high-frequency shedding patterns with their corresponding high harmonic shedding frequencies in the flow force FFTs were observed in the regions where galloping occurred. This work is partially supported by the NSF-sponsored IGERT: Offshore Wind Energy Engineering, Environmental Science, and Policy (Grant Number 1068864).

  10. Theoretical cross section calculations of medical 13N and 18F radioisotope using alpha induced reaction

    NASA Astrophysics Data System (ADS)

    Kılınç, F.; Karpuz, N.; ćetin, B.

    2017-02-01

    In medical physics, radionuclides are needed to diagnose functional disorders of organs and to diagnose and treat many diseases. Nuclear reactions are significant for the productions of radionuclides. It is important to analyze the cross sections for much different energy. In this study, reactional cross sections calculations on 13N, 18F radioisotopes are with TALYS 1.6 nuclear reaction simulation code. Cross sections calculated and experimental data taken from EXFOR library were compared

  11. Spatiotemporal Patterns Induced by Cross-Diffusion in a Three-Species Food Chain Model

    NASA Astrophysics Data System (ADS)

    Ma, Zhan-Ping; Li, Wan-Tong; Wang, Yu-Xia

    This paper focuses on a three-species Lotka-Volterra food chain model with cross-diffusion under homogeneous Neumann boundary conditions. The known results indicate that no spatiotemporal patterns happen in the corresponding reaction-diffusion system. When some cross-diffusion terms are introduced in the system, the existence of nonconstant positive steady-states as well as the Hopf bifurcation is studied. Our result shows that cross-diffusion plays a crucial role in the formation of spatiotemporal patterns, that is, it can create not only stationary patterns but also spatially inhomogeneous periodic oscillatory patterns, which is a strong contrast to the case without cross-diffusion.

  12. Measurements of Neutron Induced Cross Sections at the Oak Ridge Electron Linear Accelerator

    SciTech Connect

    Guber, K.H.; Harvey, J.A.; Hill, N.W.; Koehler, P.E.; Leal, L.C.; Sayer, R.O.; Spencer, R.R.

    1999-09-20

    We have used the Oak Ridge Electron Linear Accelerator (ORELA) to measure neutron total and the fission cross sections of 233U in the energy range from 0.36 eV to ~700 keV. We report average fission and total cross sections. Also, we measured the neutron total cross sections of 27Al and Natural chlorine as well as the capture cross section of Al over an energy range from 100 eV up to about 400 keV.

  13. Structural Characterization of Formaldehyde-induced Cross-links Between Amino Acids and Deoxynucleosides and Their Oligomers

    PubMed Central

    Lu, Kun; Ye, Wenjie; Zhou, Li; Collins, Leonard B.; Chen, Xian

    2010-01-01

    Exposure to formaldehyde results in the formation of DNA-protein cross-links (DPCs) as a primary genotoxic effect. Although DPCs are biologically important and eight amino acids have been reported to form stable adducts with formaldehyde, the structures of these cross-links have not yet been elucidated. We have characterized formaldehyde-induced cross-links of Lys, Cys, His and Trp with dG, dA and dC. dT formed no cross-links, nor did Arg, Gln, Tyr or Asn. Reaction of formaldehyde with Lys and dG gave the highest yield of cross-linked products, followed by reaction with Cys and dG. Yields from the other coupling reactions were lower by a factor of 10 or more. Detailed structural examination by NMR and mass spectrometry established that the cross-links between amino acids and single nucleosides involve a formaldehyde-derived methylene bridge. Lys yielded two additional products with dG in which the linking structure is a 1,N2-fused triazino ring. The Lys cross-linked products were unstable at ambient temperature. Reactions between the reactive Nα-Boc-protected amino acids and the trinucleotides d(T1B2T3) where B2 is the target base G, A or C and reactions between dG, dA and dC and 8-mer peptides containing a single reactive target residue at position 5 yielded cross-linked products with structures inferred from high resolution mass spectrometry and fragmentation patterns that are consistent with those between Nα-Boc-protected amino acids and single nucleotides rigorously determined by NMR studies. These structures will provide a basis for investigation of the characteristics and properties of DPCs formed in vivo and will be helpful in identifying biomarkers for the evaluation of formaldehyde exposure both at site of contact and at distant sites. PMID:20178313

  14. Tonsillar application of killed Streptococcus mutans induces specific antibodies in rabbit saliva and blood plasma without inducing a cross-reacting antibody to human cardiac muscle.

    PubMed Central

    Fukuizumi, T; Inoue, H; Tsujisawa, T; Uchiyama, C

    1997-01-01

    When Streptococcus mutans cells are injected into the skeletal muscle of rabbits, an antibody against human cardiac muscle, as well as an anti-S. mutans antibody, is induced in blood plasma. Our previous study showed that when sheep erythrocytes are applied to palatine tonsils, an antibody against the applied cells is induced both in blood plasma and saliva. This antibody has no activity against cardiac muscle. It is not clear, however, if S. mutans application to the tonsils evokes an antibody response against cardiac muscle. In this study, we immunized rabbits against S. mutans or Streptococcus sobrinus by tonsillar application or by intramuscular injection every 3 days for 6 weeks. Tonsillar applications of formalin-killed cells of S. mutans induced saliva immunoglobulin A (IgA) and blood plasma IgG to the applied cells. In contrast, intramuscular injection of such cells induced only blood plasma IgG. When the route of immunization was intramuscular injection, antibodies in blood plasma cross-reacted with cardiac muscle. By enzyme-immunohistochemistry and Ouchterlony immunodiffusion tests, no cross-reaction to cardiac muscle was observed with the antibody in saliva or in blood plasma after the tonsillar applications. Western blotting of the S. mutans antigen showed that blood plasma from rabbits injected with S. mutans reacted with antigens of 46, 52, 62, and 85 kDa, while that from rabbits subjected to tonsillar application of S. mutans did not react with these bands. Similar results were obtained for S. sobrinus applications. Thus, tonsillar applications of mutants group streptococci induce antibodies differing in antigen specificity and do not induce any cross-reacting antibody to cardiac muscle. PMID:9353033

  15. Using DNA origami nanostructures to determine absolute cross sections for UV photon-induced DNA strand breakage.

    PubMed

    Vogel, Stefanie; Rackwitz, Jenny; Schürman, Robin; Prinz, Julia; Milosavljević, Aleksandar R; Réfrégiers, Matthieu; Giuliani, Alexandre; Bald, Ilko

    2015-11-19

    We have characterized ultraviolet (UV) photon-induced DNA strand break processes by determination of absolute cross sections for photoabsorption and for sequence-specific DNA single strand breakage induced by photons in an energy range from 6.50 to 8.94 eV. These represent the lowest-energy photons able to induce DNA strand breaks. Oligonucleotide targets are immobilized on a UV transparent substrate in controlled quantities through attachment to DNA origami templates. Photon-induced dissociation of single DNA strands is visualized and quantified using atomic force microscopy. The obtained quantum yields for strand breakage vary between 0.06 and 0.5, indicating highly efficient DNA strand breakage by UV photons, which is clearly dependent on the photon energy. Above the ionization threshold strand breakage becomes clearly the dominant form of DNA radiation damage, which is then also dependent on the nucleotide sequence.

  16. Cross Sections for Neutron-induced Reactions on Actinide Targets Extracted from Surrogate Experiments: A Status Report

    SciTech Connect

    Escher, J E; Burke, J T; Dietrich, F S; Lesher, S R; Scielzo, N D; Thompson, I J; Younes, W

    2009-10-01

    The Surrogate nuclear reactions method, an indirect approach for determining cross sections for compound-nuclear reactions involving difficult-to-measure targets, is reviewed. Focusing on cross sections for neutron-induced reactions on actinides, we review the successes of past and present applications of the method and assess its uncertainties and limitations. The approximations used in the analyses of most experiments work reasonably well for (n,f) cross sections for neutron energies above 1-2 MeV, but lead to discrepancies for low-energy (n,f) reactions, as well as for (n,{gamma}) applications. Correcting for some of the effects neglected in the approximate analyses leads to improved (n,f) results. We outline steps that will further improve the accuracy and reliability of the Surrogate method and extend its applicability to reactions that cannot be approached with the present implementation of the method.

  17. Nuclear spin-lattice relaxation at field-induced level crossings in a Cr8F8 pivalate single crystal

    NASA Astrophysics Data System (ADS)

    Yamamoto, Shoji

    2016-01-01

    We construct a microscopic theory for the proton spin-lattice relaxation-rate 1 / T1 measurements around field-induced level crossings in a single crystal of the trivalent chromium ion wheel complex [Cr8F8(OOCtBu)16] at sufficiently low temperatures [E. Micotti et al., Phys. Rev. B 72 (2005) 020405(R)]. Exactly diagonalizing a well-equipped spin Hamiltonian for the individual clusters and giving further consideration to their possible interactions, we reveal the mechanism of 1 / T1 being single-peaked normally at the first level crossing but double-peaked intriguingly around the second level crossing. We wipe out the doubt about poor crystallization and find out a solution-intramolecular alternating Dzyaloshinsky-Moriya interaction combined with intermolecular coupling of antiferromagnetic character, each of which is so weak as several tens of mK in magnitude.

  18. Heat or cold priming-induced cross-tolerance to abiotic stresses in plants: key regulators and possible mechanisms.

    PubMed

    Hossain, Mohammad Anwar; Li, Zhong-Guang; Hoque, Tahsina Sharmin; Burritt, David J; Fujita, Masayuki; Munné-Bosch, Sergi

    2017-08-04

    Plants growing under field conditions are constantly exposed, either simultaneously or sequentially, to more than one abiotic stress factor. Plants have evolved sophisticated sensory systems to perceive a number of stress signals that allow them to activate the most adequate response to grow and survive in a given environment. Recently, cross-stress tolerance (i.e. tolerance to a second, strong stress after a different type of mild primary stress) has gained attention as a potential means of producing stress-resistant crops to aid with global food security. Heat or cold priming-induced cross-tolerance is very common in plants and often results from the synergistic co-activation of multiple stress signalling pathways, which involve reactive nitrogen species (RNS), reactive oxygen species (ROS), reactive carbonyl species (RCS), plant hormones and transcription factors. Recent studies have shown that the signalling functions of ROS, RNS and RCS, most particularly hydrogen peroxide, nitric oxide (NO) and methylglyoxal (MG), provide resistance to abiotic stresses and underpin cross-stress tolerance in plants by modulating the expression of genes as well as the post-translational modification of proteins. The current review highlights the key regulators and mechanisms underlying heat or cold priming-induced cross-stress tolerance in plants, with a focus on ROS, MG and NO signalling, as well as on the role of antioxidant and glyoxalase systems, osmolytes, heat-shock proteins (HSPs) and hormones. Our aim is also to provide a comprehensive idea on the topic for researchers using heat or cold priming-induced cross-tolerance as a mechanism to improve crop yields under multiple abiotic stresses.

  19. Correlation of Intermediate Energy Proton- and Neutron-Induced Fission Cross Sections in the Lead-Bismuth Region

    NASA Astrophysics Data System (ADS)

    Smirnov, Andrey N.; Eismont, Vilen P.; Filatov, Nikolay P.; Kirillov, Sergey N.; Blomgren, Jan; Condé, Henri; Olsson, Nils; Duijvestijn, Marieke; Koning, Arjan

    2005-05-01

    Neutron- and proton-induced fission cross-sections of the lead isotopes 204,206-208Pb and 205Tl in the intermediate energy region have been measured at the Svedberg Laboratory in Uppsala, Sweden. Average fissilities of the composite nuclei and the dependence on the nucleon energy and the parameter Z2/A were determined. On this basis, the correlation between the proton- and neutron-induced fission cross sections has been established in the atomic mass region A ˜ 200 and for nucleon energies above 50 MeV, where shell effects do not play a very significant role. The correlation is discussed in the frame of results from calculations by the code TALYS.

  20. Streptococcal-vimentin cross-reactive antibodies induce microvascular cardiac endothelial proinflammatory phenotype in rheumatic heart disease

    PubMed Central

    Delunardo, F; Scalzi, V; Capozzi, A; Camerini, S; Misasi, R; Pierdominici, M; Pendolino, M; Crescenzi, M; Sorice, M; Valesini, G; Ortona, E; Alessandri, C

    2013-01-01

    Summary Rheumatic heart disease (RHD) is characterized by the presence of anti-streptococcal group A antibodies and anti-endothelial cell antibodies (AECA). Molecular mimicry between streptococcal antigens and self proteins is a hallmark of the pathogenesis of rheumatic fever. We aimed to identify, in RHD patients, autoantibodies specific to endothelial autoantigens cross-reactive with streptococcal proteins and to evaluate their role in inducing endothelial damage. We used an immunoproteomic approach with endothelial cell-surface membrane proteins in order to identify autoantigens recognized by AECA of 140 RHD patients. Cross-reactivity of purified antibodies with streptococcal proteins was analysed. Homologous peptides recognized by serum cross-reactive antibodies were found through comparing the amino acid sequence of streptococcal antigens with human antigens. To investigate interleukin (IL)-1R-associated kinase (IRAK1) and nuclear factor-κB (NF-κB) activation, we performed a Western blot analysis of whole extracts proteins from unstimulated or stimulated human microvascular cardiac endothelial cells (HMVEC-C). Adhesion molecule expression and release of proinflammatory cytokines and growth factors were studied by multiplex bead based immunoassay kits. We observed anti-vimentin antibodies in sera from 49% RHD AECA-positive patients. Cross-reactivity of purified anti-vimentin antibodies with heat shock protein (HSP)70 and streptopain streptococcal proteins was shown. Comparing the amino acid sequence of streptococcal HSP70 and streptopain with human vimentin, we found two homologous peptides recognized by serum cross-reactive antibodies. These antibodies were able to stimulate HMVEC-C inducing IRAK and NF-κB activation, adhesion molecule expression and release of proinflammatory cytokines and growth factors. In conclusion, streptococcal–vimentin cross-reactive antibodies were able to activate microvascular cardiac endothelium by amplifying the inflammatory

  1. Observation of laser-induced associative ionization in crossed-beam Na+Li collisions

    SciTech Connect

    Polak-Dingels, P.; Keller, J.; Weiner, J.; Gauthier, J.h.; Bras, N.

    1981-08-01

    We report the observation of NaLi/sup +/ produced by crossed-beam collisions of Na and Li in the presence of a single laser field. The magnitude of the cross section and its dependence on laser intensity are in accord with a simple second-order perturbation theory.

  2. Using a Time Projection Chamber to Measure High Precision Neutron-Induced Fission Cross Sections

    SciTech Connect

    Manning, Brett

    2015-08-06

    2014 LANSCE run cycle data will provide a preliminary 239Pu(n,f) cross section and will quantify uncertainties: PID and Target/beam non-uniformities. Continued running during the 2015 LANSCE run cycle: Thin targets to see both fission fragments and 239Pu(n,f) cross section and fully quantified uncertainties

  3. Cross-shelf transport induced by coastal trapped waves along the coast of East China Sea

    NASA Astrophysics Data System (ADS)

    Jiang, Lin; Dong, Changming; Yin, Liping

    2017-08-01

    Cross-shelf transport is important due to its role in the transport of nutrients, larvae, sediments, and pollutants. The role of coastal trapped waves (CTWs) and their contribution to the cross-shelf transport is presently unknown. The impact of wind-driven CTWs on the structure of the cross-shelf currents and transport is investigated in the East China Sea (ECS) starting from theory. The cross-shelf currents are divided into four terms: the geostrophic balance (GB) term, the second-order wave (SOW) term, the bottom friction (BF) term and Ekman (EK) term, as well as three modes: the Kelvin wave (KW) mode, the first shelf wave (SW1) mode and the second shelf wave (SW2) mode. Comparison among these decompositions shows that (1) for the four terms, the effect of the GB and EK terms is continual, while that of the BF term is confined to 60u2013240 km offshore, and the contribution of the SOW term can be ignored; (2) for the three modes, the KW and SW1 modes are dominant in cross-shelf transport. The results show that the total cross-shelf transport travels onshore under idealized wind stress on the order of 10-1, and it increases along the cross-shelf direction and peaks about -0.73 Sv at the continental shelf margin. With the increase of linear bottom friction coefficient, the cross-shelf transport declines with distance with the slope becoming more uniform.

  4. Cationic Lipid/DNA Complex-Adjuvanted Influenza A Virus Vaccination Induces Robust Cross-Protective Immunity▿

    PubMed Central

    Hong, David K.; Chang, Stella; Botham, Crystal M.; Giffon, Thierry D.; Fairman, Jeffery; Lewis, David B.

    2010-01-01

    Influenza A virus is a negative-strand segmented RNA virus in which antigenically distinct viral subtypes are defined by the hemagglutinin (HA) and neuraminidase (NA) major viral surface proteins. An ideal inactivated vaccine for influenza A virus would induce not only highly robust strain-specific humoral and T-cell immune responses but also cross-protective immunity in which an immune response to antigens from a particular viral subtype (e.g., H3N2) would protect against other viral subtypes (e.g., H1N1). Cross-protective immunity would help limit outbreaks from newly emerging antigenically novel strains. Here, we show in mice that the addition of cationic lipid/noncoding DNA complexes (CLDC) as adjuvant to whole inactivated influenza A virus vaccine induces significantly more robust adaptive immune responses both in quantity and quality than aluminum hydroxide (alum), which is currently the most widely used adjuvant in clinical human vaccination. CLDC-adjuvanted vaccine induced higher total influenza virus-specific IgG, particularly for the IgG2a/c subclass. Higher levels of multicytokine-producing influenza virus-specific CD4 and CD8 T cells were induced by CLDC-adjuvanted vaccine than with alum-adjuvanted vaccine. Importantly, CLDC-adjuvanted vaccine provided significant cross-protection from either a sublethal or lethal influenza A viral challenge with a different subtype than that used for vaccination. This superior cross-protection afforded by the CLDC adjuvant required CD8 T-cell recognition of viral peptides presented by classical major histocompatibility complex class I proteins. Together, these results suggest that CLDC has particular promise for vaccine strategies in which T cells play an important role and may offer new opportunities for more effective control of human influenza epidemics and pandemics by inactivated influenza virus vaccine. PMID:20943978

  5. Aluminum-induced dreierketten chain cross-links increase the mechanical properties of nanocrystalline calcium aluminosilicate hydrate.

    PubMed

    Geng, Guoqing; Myers, Rupert J; Li, Jiaqi; Maboudian, Roya; Carraro, Carlo; Shapiro, David A; Monteiro, Paulo J M

    2017-03-10

    The incorporation of Al and increased curing temperature promotes the crystallization and cross-linking of calcium (alumino)silicate hydrate (C-(A-)S-H), which is the primary binding phase in most contemporary concrete materials. However, the influence of Al-induced structural changes on the mechanical properties at atomistic scale is not well understood. Herein, synchrotron radiation-based high-pressure X-ray diffraction is used to quantify the influence of dreierketten chain cross-linking on the anisotropic mechanical behavior of C-(A-)S-H. We show that the ab-planar stiffness is independent of dreierketten chain defects, e.g. vacancies in bridging tetrahedra sites and Al for Si substitution. The c-axis of non-cross-linked C-(A-)S-H is more deformable due to the softer interlayer opening but stiffens with decreased spacing and/or increased zeolitic water and Ca(2+) of the interlayer. Dreierketten chain cross-links act as 'columns' to resist compression, thus increasing the bulk modulus of C-(A-)S-H. We provide the first experimental evidence on the influence of the Al-induced atomistic configurational change on the mechanical properties of C-(A-)S-H. Our work advances the fundamental knowledge of C-(A-)S-H on the lowest level of its hierarchical structure, and thus can impact the way that innovative C-(A-)S-H-based cementitious materials are developed using a 'bottom-up' approach.

  6. Aluminum-induced dreierketten chain cross-links increase the mechanical properties of nanocrystalline calcium aluminosilicate hydrate

    NASA Astrophysics Data System (ADS)

    Geng, Guoqing; Myers, Rupert J.; Li, Jiaqi; Maboudian, Roya; Carraro, Carlo; Shapiro, David A.; Monteiro, Paulo J. M.

    2017-03-01

    The incorporation of Al and increased curing temperature promotes the crystallization and cross-linking of calcium (alumino)silicate hydrate (C-(A-)S-H), which is the primary binding phase in most contemporary concrete materials. However, the influence of Al-induced structural changes on the mechanical properties at atomistic scale is not well understood. Herein, synchrotron radiation-based high-pressure X-ray diffraction is used to quantify the influence of dreierketten chain cross-linking on the anisotropic mechanical behavior of C-(A-)S-H. We show that the ab-planar stiffness is independent of dreierketten chain defects, e.g. vacancies in bridging tetrahedra sites and Al for Si substitution. The c-axis of non-cross-linked C-(A-)S-H is more deformable due to the softer interlayer opening but stiffens with decreased spacing and/or increased zeolitic water and Ca2+ of the interlayer. Dreierketten chain cross-links act as ‘columns’ to resist compression, thus increasing the bulk modulus of C-(A-)S-H. We provide the first experimental evidence on the influence of the Al-induced atomistic configurational change on the mechanical properties of C-(A-)S-H. Our work advances the fundamental knowledge of C-(A-)S-H on the lowest level of its hierarchical structure, and thus can impact the way that innovative C-(A-)S-H-based cementitious materials are developed using a ‘bottom-up’ approach.

  7. Measuring reaction probability ratios to simulate neutron-induced cross-sections of short-lived nuclei

    NASA Astrophysics Data System (ADS)

    Plettner, C.; Ai, H.; Beausang, C. W.; Bernstein, L. A.; Ahle, L.; Amro, H.; Babilon, M.; Burke, J. T.; Caggiano, J. A.; Casten, R. F.; Church, J. A.; Cooper, J. R.; Crider, B.; Gürdal, G.; Heinz, A.; McCutchan, E. A.; Moody, K.; Punyon, J. A.; Qian, J.; Ressler, J. J.; Schiller, A.; Williams, E.; Younes, W.

    2005-10-01

    Measuring the neutron-induced fission cross-sections of short-lived nuclei represents an experimental challenge due to target activity and the low intensity of neutron beams. One way to alleviate the problems inherent in the direct measurement is to use the surrogate method, where one measures the decay probability of the same compound nucleus formed using a charged beam and a stable target. The decay probability of the compound nucleus is then used to estimate the neutron-induced cross-section. As an extension to the surrogate method, we introduce a new method of reporting the fission probabilities of two compound nuclei as a ratio, which has the advantage of removing most of the systematic uncertainties. The ratio method was checked in a known case, the 236U(n, f)/238U(n, f) cross-section ratio, which turned out to be the same as the probability ratio of P(236U(d, pf))/P(238U(d, pf)). As an application, the 237U(n, f)/235U(n, f) cross-section ratio was inferred, on the basis of the measured P(238U(d, d'f))/P(236U(d, d'f)) probability ratio.

  8. DNA cross-linking and single-strand breaks induced by teratogenic concentrations of 4-hydroperoxycyclophosphamide and phosphoramide mustard in postimplantation rat embryos.

    PubMed

    Little, S A; Mirkes, P E

    1987-10-15

    Postimplantation rat embryos (Day 10) were exposed in vitro to teratogenic concentrations of 4-hydroperoxycyclophosphamide, an activated form of cyclophosphamide, and phosphoramide mustard, the major teratogenic metabolite of cyclophosphamide. Following a 5-h exposure to these agents, drug-induced DNA damage was assessed by alkaline elution. Both drugs induced detectable DNA cross-linking at teratogenic concentrations. Alkaline elution combined with proteinase K digestion indicated that approximately half of the DNA cross-linking was DNA-DNA cross-linking and the other half was DNA-protein cross-linking. In addition to DNA cross-linking, phosphoramide mustard produced DNA strand breaks and/or alkaline labile sites. However, 4-hydroperoxycyclophosphamide did not produce detectable DNA strand breaks or alkaline labile sites. Our data also indicate that the induction of abnormal morphogenesis by 4-hydroperoxycyclophosphamide and phosphoramide mustard is correlated with drug-induced DNA cross-linking.

  9. Physically Cross-linked Polymer Binder Induced by Reversible Acid-Base Interaction for High-Performance Silicon Composite Anodes.

    PubMed

    Lim, Sanghyun; Chu, Hodong; Lee, Kukjoo; Yim, Taeeun; Kim, Young-Jun; Mun, Junyoung; Kim, Tae-Hyun

    2015-10-28

    Silicon is greatly promising for high-capacity anode materials in lithium-ion batteries (LIBs) due to their exceptionally high theoretical capacity. However, it has a big challenge of severe volume changes during charge and discharge, resulting in substantial deterioration of the electrode and restricting its practical application. This conflict requires a novel binder system enabling reliable cyclability to hold silicon particles without severe disintegration of the electrode. Here, a physically cross-linked polymer binder induced by reversible acid-base interaction is reported for high performance silicon-anodes. Chemical cross-linking of polymer binders, mainly based on acidic polymers including poly(acrylic acid) (PAA), have been suggested as effective ways to accommodate the volume expansion of Si-based electrodes. Unlike the common chemical cross-linking, which causes a gradual and nonreversible fracturing of the cross-linked network, a physically cross-linked binder based on PAA-PBI (poly(benzimidazole)) efficiently holds the Si particles even after the large volume changes due to its ability to reversibly reconstruct ionic bonds. The PBI-containing binder, PAA-PBI-2, exhibited large capacity (1376.7 mAh g(-1)), high Coulombic efficiency (99.1%) and excellent cyclability (751.0 mAh g(-1) after 100 cycles). This simple yet efficient method is promising to solve the failures relating with pulverization and isolation from the severe volume changes of the Si electrode, and advance the realization of high-capacity LIBs.

  10. Lysyl hydroxylase 2 induces a collagen cross-link switch in tumor stroma

    PubMed Central

    Chen, Yulong; Terajima, Masahiko; Yang, Yanan; Sun, Li; Ahn, Young-Ho; Pankova, Daniela; Puperi, Daniel S.; Watanabe, Takeshi; Kim, Min P.; Blackmon, Shanda H.; Rodriguez, Jaime; Liu, Hui; Behrens, Carmen; Wistuba, Ignacio I.; Minelli, Rosalba; Scott, Kenneth L.; Sanchez-Adams, Johannah; Guilak, Farshid; Pati, Debananda; Thilaganathan, Nishan; Burns, Alan R.; Creighton, Chad J.; Martinez, Elisabeth D.; Zal, Tomasz; Grande-Allen, K. Jane; Yamauchi, Mitsuo; Kurie, Jonathan M.

    2015-01-01

    Epithelial tumor metastasis is preceded by an accumulation of collagen cross-links that heighten stromal stiffness and stimulate the invasive properties of tumor cells. However, the biochemical nature of collagen cross-links in cancer is still unclear. Here, we postulated that epithelial tumorigenesis is accompanied by changes in the biochemical type of collagen cross-links. Utilizing resected human lung cancer tissues and a p21CIP1/WAF1-deficient, K-rasG12D-expressing murine metastatic lung cancer model, we showed that, relative to normal lung tissues, tumor stroma contains higher levels of hydroxylysine aldehyde–derived collagen cross-links (HLCCs) and lower levels of lysine aldehyde–derived cross-links (LCCs), which are the predominant types of collagen cross-links in skeletal tissues and soft tissues, respectively. Gain- and loss-of-function studies in tumor cells showed that lysyl hydroxylase 2 (LH2), which hydroxylates telopeptidyl lysine residues on collagen, shifted the tumor stroma toward a high-HLCC, low-LCC state, increased tumor stiffness, and enhanced tumor cell invasion and metastasis. Together, our data indicate that LH2 enhances the metastatic properties of tumor cells and functions as a regulatory switch that controls the relative abundance of biochemically distinct types of collagen cross-links in the tumor stroma. PMID:25664850

  11. Resonance Analysis and Evaluation of the Uranium -235 Neutron-Induced Cross-Sections

    NASA Astrophysics Data System (ADS)

    Leal, Luiz Carlos

    Neutron cross sections of fissile nuclei are of considerable interest for the understanding of parameters such as resonance absorption, resonance escape probability, resonance self-shielding, and the dependence of the reactivity on temperature. In the present study, new techniques for the evaluation of the ^{235}U neutron cross sections are described. The Reich-Moore formalism of the Bayesian computer code SAMMY was used to perform consistent R-matrix multilevel analyses of the selected neutron cross-section data. The Delta_3 -statistics of Dyson and Mehta, along with high -resolution data and the spin-separated fission cross-section data, have provided the possibility of developing a new methodology for the analysis and evaluation of neutron -nucleus cross-sections. The result of the analysis consists of a set of resonance parameters which describe the ^{235}U neutron cross sections up to 500 eV. The set of resonance parameters obtained through a R-matrix analysis are expected to satisfy statistical properties which lead to information on the nuclear structure. The resonance parameters were tested and showed good agreement with the theory. It is expected that the parametrization of the ^{235}U neutron cross sections obtained in this dissertation represents the current state of art in data as well as in theory and, therefore, can be of direct use in reactor calculations.

  12. Stress-induced traveltime variations at SAFOD revealed by continuous cross-well active source monitoring

    NASA Astrophysics Data System (ADS)

    Yang, C.; Niu, F.; Daley, T. M.; Taira, T.

    2016-12-01

    The time-varying stress/strain field at seismogenic depths is arguable the single most important property controlling the sequencing and nucleation of seismic events. The measurement of stress, however, is notoriously difficult, particularly at seismogenic depths. Seismic imaging, in principle, has the capability to provide this critical depth component. Numerous laboratory studies over the last few decades have shown that the elastic properties of crustal rocks clearly exhibit stress dependence. Such dependence is attributed to the opening/closing of fluid-filled cracks in response to changes in the stress normal to the crack surface. Temporal changes in stress are thus, in principle, measurable through seismic imaging of changes in elastic properties, such as seismic velocity field. We have been conducting continuous cross-well active source experiments utilizing the SAFOD (San Andreas Fault Observatory at Depth) pilot and main holes to develop a seismic stress meter to monitor the subsurface stress field by exploring the velocity-stress sensitivity. In a two-month period in 2005-2006, we found a 0.3% change in the average S-wave velocity, which shows a good correlation with barometric pressure, corresponding to a stress sensitivity of 2.4x10-7Pa-1. We also observed two large excursions in the delay time measurement, corresponding to 0.55% and 0.15% decreases of seismic velocity, that are coincident with two earthquakes that are among those predicted to produce the largest coseismic stress changes. The two excursions started approximately 10 and 2 hours before the events, respectively, suggesting that they may be related to pre-rupture stress induced changes in crack properties, as observed in early laboratory studies. We repeated the experiment in early 2010 with a slightly different experiment configuration, and collected 40-days data. The new data confirmed the negative correlation between traveltime and barometric pressure. The estimated stress sensitivity is

  13. Characteristics of ethanol-induced behavioral sensitization in rats: Molecular mediators and cross-sensitization between ethanol and cocaine.

    PubMed

    Xu, Shijie; Kang, Ung Gu

    2017-09-01

    Repeated exposure to drugs of abuse can induce a progressive increase in locomotor activity, known as behavioral sensitization. However, little is known about behavioral sensitization to ethanol. We examined whether ethanol could induce behavioral sensitization and investigated several molecular changes accompanying sensitization. We also assessed whether "cross-sensitization" occurred between ethanol and cocaine, another abused drug. Ethanol-induced sensitization was examined in rats after ethanol treatment (0.5 or 2g/kg) for 15days. The biochemical effects of low- or high-dose ethanol were examined in terms of N-methyl-d-aspartate (NMDA) receptor subunit phosphorylation or expression. Neuronal activity after ethanol treatment was assessed by measuring the level of early growth response (Egr-1) expression. Ethanol-induced behavioral sensitization was observed at the low dose (0.5g/kg) but not the high dose (2g/kg). Although acute treatment with the sensitizing dose of ethanol robustly increased Egr-1 protein and mRNA levels, the expression and phosphorylation of NMDA receptor subunits were not affected. The biochemical responses to ethanol seemed to be enhanced in ethanol-sensitized animals. Cross-sensitization between ethanol and cocaine was observed, which supports the hypothesis that there are commonalities among substances in the pathophysiology of substance dependence. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Real-time envelope cross-correlation detector: application to induced seismicity in the Insheim and Landau deep geothermal reservoirs

    NASA Astrophysics Data System (ADS)

    Vasterling, Margarete; Wegler, Ulrich; Becker, Jan; Brüstle, Andrea; Bischoff, Monika

    2017-01-01

    We develop and test a real-time envelope cross-correlation detector for use in seismic response plans to mitigate hazard of induced seismicity. The incoming seismological data are cross-correlated in real-time with a set of previously recorded master events. For robustness against small changes in the earthquake source locations or in the focal mechanisms we cross-correlate the envelopes of the seismograms rather than the seismograms themselves. Two sequenced detection conditions are implemented: After passing a single trace cross-correlation condition, a network cross-correlation is calculated taking amplitude ratios between stations into account. Besides detecting the earthquake and assigning it to the respective reservoir, real-time magnitudes are important for seismic response plans. We estimate the magnitudes of induced microseismicity using the relative amplitudes between master event and detected event. The real-time detector is implemented as a SeisComP3 module. We carry out offline and online performance tests using seismic monitoring data of the Insheim and Landau geothermal power plants (Upper Rhine Graben, Germany), also including blasts from a nearby quarry. The comparison of the automatic real-time catalogue with a manually processed catalogue shows, that with the implemented parameters events are always correctly assigned to the respective reservoir (4 km distance between reservoirs) or the quarry (8 km and 10 km distance, respectively, from the reservoirs). The real-time catalogue achieves a magnitude of completeness around 0.0. Four per cent of the events assigned to the Insheim reservoir and zero per cent of the Landau events are misdetections. All wrong detections are local tectonic events, whereas none are caused by seismic noise.

  15. Photosensitized UVA-Induced Cross-Linking between Human DNA Repair and Replication Proteins and DNA Revealed by Proteomic Analysis

    PubMed Central

    2016-01-01

    Long wavelength ultraviolet radiation (UVA, 320–400 nm) interacts with chromophores present in human cells to induce reactive oxygen species (ROS) that damage both DNA and proteins. ROS levels are amplified, and the damaging effects of UVA are exacerbated if the cells are irradiated in the presence of UVA photosensitizers such as 6-thioguanine (6-TG), a strong UVA chromophore that is extensively incorporated into the DNA of dividing cells, or the fluoroquinolone antibiotic ciprofloxacin. Both DNA-embedded 6-TG and ciprofloxacin combine synergistically with UVA to generate high levels of ROS. Importantly, the extensive protein damage induced by these photosensitizer+UVA combinations inhibits DNA repair. DNA is maintained in intimate contact with the proteins that effect its replication, transcription, and repair, and DNA–protein cross-links (DPCs) are a recognized reaction product of ROS. Cross-linking of DNA metabolizing proteins would compromise these processes by introducing physical blocks and by depleting active proteins. We describe a sensitive and statistically rigorous method to analyze DPCs in cultured human cells. Application of this proteomics-based analysis to cells treated with 6-TG+UVA and ciprofloxacin+UVA identified proteins involved in DNA repair, replication, and gene expression among those most vulnerable to cross-linking under oxidative conditions. PMID:27654267

  16. X-ray-induced electron cascades in dielectrics modeled with XCASCADE code: effect of impact ionization cross sections

    NASA Astrophysics Data System (ADS)

    Medvedev, Nikita A.

    2015-05-01

    Characterization of a free-electron laser (FEL) pulse can be done with a pump-probe scheme, using an FEL pump and a visible light probe on an optically transparent solid-state target. With such experimental scheme, pulse duration can be monitored on a shot-to-shot basis. It relies on the changes in optical properties induced by the FEL excitation of electrons. Here we analyze effects of different cross sections used in the modeling of electron kinetics. XCASCADE, a Monte Carlo toolkit for modeling x-ray-induced electron cascades (N. Medvedev, Appl. Phys. B 118 (2015) 417), is used for this purpose. Two different cross sections are compared: atomic BEB model vs complex-dielectric function formalism that accounts for collective effects in solids. It is shown that for photon and electron energies above a few tens of eV, the both models coincide very closely. For lower energies in the VUV regime, the difference in the cross sections become more significant, nevertheless producing qualitatively similar electron kinetics and increase in the density of excited electrons.

  17. Optical chirality in AgCl-Ag thin films through formation of laser-induced planar crossed-chain nanostructures

    NASA Astrophysics Data System (ADS)

    Nahal, Arashmid; Kashani, Somayeh

    2017-09-01

    Irradiation of AgCl-Ag thin films by a linearly polarized He-Ne laser beam results in the formation of self-organized periodic nanostructures. As a result of secondary irradiation of the initially exposed sample by the same linearly polarized He-Ne laser beam, but with different orientations of polarization, a complex crossed-chain nanostructure forms. We found that such a complex nanostructure has noticeable chirality and increased optical anisotropy, resulting in optical activity of the sample. Double exposure produces two gratings, crossing each other with angle α, which leads to the formation of crossed building blocks with chiroptical effects. It is established that the amount and the sign of the angle between the two laser-induced gratings (±α) determine the amount and the direction of rotation of the linearly polarized probe beam, respectively. We have also observed an induced anisotropy-dependent ellipticity for the probe light, which is passed through the sample. It is shown that the amount of ellipticity depends on the angle α.

  18. Measurement of proton-induced target fragmentation cross sections in carbon

    NASA Astrophysics Data System (ADS)

    Matsushita, K.; Nishio, T.; Tanaka, S.; Tsuneda, M.; Sugiura, A.; Ieki, K.

    2016-02-01

    In proton therapy, positron emitter nuclei are generated via the target nuclear fragmentation reactions between irradiated proton and nuclei constituting a human body. The proton-irradiated volume can be confirmed with measurement of annihilation γ-rays from the generated positron emitter nuclei. To achieve the high accuracy of proton therapy, in vivo dosimetry, i.e., evaluation of the irradiated dose during the treatment is important. To convert the measured activity distribution to irradiated dose, cross-sectional data for positron emitter production is necessary, which is currently insufficient in the treatment area. The purpose of this study is to collect cross-sectional data of 12C (p , pn)11C and 12C (p , p 2 n)10C reactions between the incident proton and carbon nuclei, which are important target nuclear fragmentation reactions, to estimate the range and exposure dose distribution in the patient's body. Using planar-type PET capable of measuring annihilation γ-rays at high positional resolution and thick polyethylene target, we measured cross-sectional data in continuous wide energy range. The cross section of 12C (p , pn)11C is in good agreement with existing experimental data. The cross section of 12C (p , p 2 n)10C is reported for the first data in the low-energy range of 67.6-10.5 MeV near the Bragg peak of proton beam.

  19. Aluminum induces neurofilament aggregation by stabilizing cross-bridging of phosphorylated c-terminal sidearms.

    PubMed

    Kushkuley, Jacob; Metkar, Shailesh; Chan, Walter K-H; Lee, Sangmook; Shea, Thomas B

    2010-03-31

    Exposure to neurotoxin aluminum neurotoxicity is accompanied by the perikaryal accumulation of tangles of phosphorylated neurofilaments (NFs). We examined their formation and reversibility under cell-free conditions. AlCl3 induced dose-dependent formation of NF aggregates, ultimately incorporating 100% of detectable NFs. The same concentration of CaCl2 induced approximately 25% of NFs to form longitudinal dimers and did not induce aggregation. AlCl3 induced similar percentages of aggregates in the presence or absence of CaCl2, and CaCl2 could not reduce pre-formed aggregates. CaCl(2)-induced dimers and AlCl(3)-induced aggregates were prevented by prior NF dephosphorylation. While CaCl(2)-induced dimers were dissociated by phosphatase treatment, AlCl(3)-induced aggregates were only reduced by approximately 50%, suggesting that aggregates may sequester phosphorylation sites. Since phosphatases regulate NF phosphorylation within perikarya, inhibition of NF dephosphorylation by aluminum would promote perikaryal NF phosphorylation and foster precocious phospho-dependent NF-NF associations. These findings are consistent with the notion that prolonged interactions induced among phospho-NFs by the trivalent aluminum impairs axonal transport and promotes perikaryal aggregation. Copyright 2010. Published by Elsevier B.V.

  20. Absolute Cross Sections for Proton Induced Reactions on 147,149Sm Below the Coulomb Barrier

    NASA Astrophysics Data System (ADS)

    Gheorghe, I.; Filipescu, D.; Glodariu, T.; Bucurescu, D.; Cata-Danil, I.; Cata-Danil, G.; Deleanu, D.; Ghita, D.; Ivascu, M.; Lica, R.; Marginean, N.; Marginean, R.; Mihai, C.; Negret, A.; Sava, T.; Stroe, L.; Toma, S.; Sima, O.; Sin, M.

    2014-05-01

    Cross sections for 147,149Sm(p,n)147,149Eu and 147,149Sm(p, γ)148,150Eu were measured using the activation method. The results are compared to the predictions of the Hauser-Feshbach statistical model. Different γ-ray strength functions have been tested against the experimental values. In the case of 150Eu, in order to reproduce the experimental isomeric population cross sections, various scenarios for unknown branching ratios of certain discrete states have been discussed. The results provide constraints for the optical model parameters dedicated to this insufficiently known area of isotopes. Such cross sections for (p, γ) reactions at energies below the Coulomb barrier are valuable for p-process nucleosynthesis calculations.

  1. Measurement of 230Pa and 186Re Production Cross Sections Induced by Deuterons at Arronax Facility

    NASA Astrophysics Data System (ADS)

    Duchemin, Charlotte; Guertin, Arnaud; Metivier, Vincent; Haddad, Ferid; Michel, Nathalie

    2014-02-01

    A dedicated program has been launched on production of innovative radionuclides for PET imaging and for β- and α targeted radiotherapy using proton or α particles at the ARRONAX cyclotron. Since the accelerator is also able to deliver deuteron beams up to 35 MeV, we have reconsidered the possibility of using them to produce medical isotopes. Two isotopes dedicated to targeted therapy have been considered: 226Th, a decay product of 230Pa, and 186Re. The production cross sections of 230Pa and 186Re, as well as those of the contaminants created during the irradiation, have been determined by the stacked-foil technique using deuteron beams. Experimental values have been quantified using a referenced cross section. The measured cross sections have been used to determine expected production yields and compared with the calculated values obtained using the Talys code with default parameters.

  2. Endothelin(A)-endothelin(B) receptor cross talk in endothelin-1-induced contraction of smooth muscle.

    PubMed

    Rapoport, Robert M; Zuccarello, Mario

    2012-11-01

    The efficacy of selective endothelin (ET) receptor antagonists may be limited by a functional interaction between the ET(A) and ET(B) receptors. This interaction, also termed "cross talk", is characterized by the dependency of the inhibition of an ET-1 response due to antagonism of one ET receptor subtype upon concomitant antagonism of the other ET receptor subtype. Although a reduction in ET(A)-ET(B) receptor cross talk would presumably increase the efficacy of selective ET receptor antagonists, an approach that accomplishes this aim is largely absent due to a lack of mechanistic understanding. Toward this goal, we evaluated the characteristics and potential dependencies of cross talk in smooth muscle. Smooth muscle was adopted as an exemplar not only because cross talk is widely reported in this tissue type, thereby allowing numerous comparisons, but also significant controversy surrounds the use of selective versus nonselective ET receptor antagonists in ET-1-related pathophysiologies involving smooth muscle. Based on this evaluation, we suggest that ET(A)-ET(B) receptor cross talk is a dynamic process directed by either or both ET receptor subtypes and expressed to varying magnitudes depending on the ET-1 and selective ET receptor antagonist concentrations, tone due to intraluminal pressure/stretch, agonists acting at receptors other than the ET(A)/ET(B) receptors, and endothelial/epithelial function. It is speculated that ET(A)-ET(B) receptor cross talk occurs through signal transduction pathways along with changes at the receptor level. Pharmacologic intervention of the signaling pathways could increase the therapeutic efficacy of ET receptor antagonists.

  3. Bidirectional cytoplasmic incompatibility induced by cross-order transfection of Wolbachia: implications for control of the host population.

    PubMed

    Zhong, Yong; Li, Zheng-Xi

    2014-10-01

    Wolbachia are widespread endosymbionts in arthropods and some nematodes. This genus of bacteria is known to manipulate host reproduction by inducing cytoplasmic incompatibility (CI). This important phenotype is implicated in the control of host populations since Wolbachia can suppress host populations through the induction of CI in a way similar to the sterile insect technique. Here, we identified a candidate CI-inducing Wolbachia strain from the parasitic wasp Scleroderma guani (wSguBJ) by sequencing and phylogenetic analysis. This Wolbachia strain was then isolated, purified, and artificially transfected into the new whitefly host Bemisia tabaci through nymphal microinjection. Infection frequency monitoring by molecular detection showed that 60-80 % of the offspring from transfected whitefly populations was infected with wSguBJ six generations after the transfer. Laboratory rearing experiments indicated that the artificial transfection caused no significant difference in the numbers of offspring between the transfected and naturally infected populations and had no significant detrimental effects on the development of transfected males, although the development of transfected females was delayed. Reciprocal crossings revealed that bidirectional CI was induced between the transfected and naturally infected whiteflies. These data indicated that the cross-order transfer of the heterologous Wolbachia strain by nymphal microinjection was successful. Mass release of the transfected males that could stably carry the heterologous Wolbachia without significant compromise of fecundity/development may provide an alternative approach to control of host populations.

  4. Oxidative DNA adducts and DNA-protein cross-links are the major DNA lesions induced by arsenite.

    PubMed Central

    Bau, Da-Tian; Wang, Tsu-Shing; Chung, Chiao-Hui; Wang, Alexander S S; Wang, Alexander S S; Jan, Kun-Yan

    2002-01-01

    Arsenic is recognized to be a nonmutagenic carcinogen because it induces DNA damage only at very high concentrations. However, many more DNA strand breaks could be detected by digesting the DNA of arsenite-treated cells with endonuclease III, formamidopyrimidine-DNA glycosylase, and proteinase K. By doing so, arsenite could be shown to induce DNA damage in human cells within a pathologically meaningful concentration range. Oxidized guanine products were detected in all arsenite-treated human cells examined. DNA-protein cross-links were also detected in arsenite-treated NB4 and HL60 cells. In human umbilical vein endothelial cells, the induction of oxidized guanine products by arsenite was sensitive to inhibitors of nitric oxide (NO) synthase but not to oxidant modulators, whereas the opposite result was obtained in vascular smooth muscle cells. On the other hand, the arsenite-induced oxidized guanine products and DNA-protein cross-links in NB4 and HL60 cells were sensitive to modulators of calcium, NO synthase, oxidant, and myeloperoxidase. Therefore, although oxidized guanine products were detected in all the human cells treated with arsenite, the pathways could be different in different cell types. Because the sensitivity and the mechanism of arsenic intoxication are cell specific, it is important that target tissues and target cells are used for investigations. It is also important that pathologically or pharmacologically meaningful concentrations of arsenic are used. This is because in most cases we are dealing with the chronic effect rather than acute toxicity. PMID:12426126

  5. UV-induced pyrimidine dimers and trimethylpsoralen cross-links do not alter chromatin folding in vitro

    SciTech Connect

    Gale, J.M.; Smerdon, M.J.

    1988-09-20

    We have examined the ability of intact and histone H1 depleted chromatin fibers to fold into higher ordered structures in vitro following DNA damage by two different agents: UV irradiation at 254 nm and trimethylpsoralen plus near-UV light. Both agents damage DNA specifically, yet cause different degrees of unwinding (and possibly bending) of the DNA helix. In addition, trimethylpsoralen forms interstrand DNA cross-links. The structural transitions of intact and histone H1 depleted chromatin fibers, induced by NaCl, were monitored by analytical ultracentrifugation, light scattering, and circular dichroism. Our results indicate that when chromatin fibers contain even large, nonphysiological amounts of DNA photodamage by either agent, the salt-induced folding of these fibers into higher ordered structures is unaffected. The compact 30-nm fiber must therefore be able to accommodate a large amount of DNA photodamage (greater than one UV-induced photoproduct or trimethylpsoralen interstrand cross-link per nucleosome) with little or no change in the overall size or compaction of this structure.

  6. Calculated neutron-induced cross sections for /sup 53/Cr from 1 to 20 MeV

    SciTech Connect

    Shibata, K.; Hetrick, D.M.

    1987-05-01

    Neutron-induced cross sections of /sup 53/Cr have been calculated in the energy regions from 1 to 20 MeV. The quantities obtained are the cross sections for the reactions (n,n'..gamma..), (n,2n), (n,np), (n,n..cap alpha..), (n,p..gamma..), (n,pn), (n,..cap alpha gamma..), (n,..cap alpha..n), (n,d), (n,t), (n,/sup 3/He), and (n,..gamma..), as well as the spectra of emitted neutrons, protons, alpha particles, and gamma rays. The precompound process was included above 5 MeV in addition to the compound process. For the inelastic scattering, the contribution of the direct interaction was calculated with DWBA. 36 refs., 23 figs., 11 tabs.

  7. Activation cross sections of deuteron induced reactions on niobium in the 30-50 MeV energy range

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.; Ignatyuk, A. V.

    2016-04-01

    Activation cross-sections of deuterons induced reactions on Nb targets were determined with the aim of different applications and comparison with theoretical models. We present the experimental excitation functions of 93Nb(d,x)93m,90Mo, 92m,91m,90Nb, 89,88Zr and 88,87m,87gY in the energy range of 30-50 MeV. The results were compared with earlier measurements and with the cross-sections calculated by means of the theoretical model codes ALICE-D, EMPIRE-D and TALYS (on-line TENDL-2014 and TENDL-2015 libraries). Possible applications of the radioisotopes are discussed in detail.

  8. Neutron-induced fission cross section of U234 measured at the CERN n_TOF facility

    NASA Astrophysics Data System (ADS)

    Karadimos, D.; Vlastou, R.; Ioannidis, K.; Demetriou, P.; Diakaki, M.; Vlachoudis, V.; Pavlopoulos, P.; Konovalov, V.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrillo de Albornoz, A.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; David, S.; Dolfini, R.; Domingo-Pardo, C.; Dorochenko, A.; Dridi, W.; Duran, I.; Eleftheriadis, Ch.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Fuji, K.; Furman, W.; Goncalves, I.; Gallino, R.; Cennini, P.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karamanis, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Kolokolov, D.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Massimi, C.; Mastinu, P.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Sedysheva, M.; Stamoulis, K.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Tsinganis, A.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Voss, F.; Wendler, H.; Wiescher, M.; Wisshak, K.; n TOF Collaboration

    2014-04-01

    The neutron-induced fission cross section of U234 has been measured at the CERN n_TOF facility relative to the standard fission cross section of U235 from 20 keV to 1.4 MeV and of U238 from 1.4 to 200 MeV. A fast ionization chamber (FIC) was used as a fission fragment detector with a detection efficiency of no less than 97%. The high instantaneous flux and the low background characterizing the n_TOF facility resulted in wide-energy-range data (0.02 to 200 MeV), with high energy resolution, high statistics, and systematic uncertainties bellow 3%. Previous investigations around the energy of the fission threshold revealed structures attributed to β-vibrational levels, which have been confirmed by the present measurements. Theoretical calculations have been performed, employing the talys code with model parameters tuned to fairly reproduce the experimental data.

  9. Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemsitry in the region of Thulium, Lutetium, and Tantalum I. Results of Built in Spherical Symmetry in a Deformed Region

    SciTech Connect

    Hoffman, R. D.

    2013-09-06

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from Terbium (Z = 65) to Rhenium (Z = 75). Of particular interest are the cross sections on Tm, Lu, and Ta including reactions on isomeric targets.

  10. Aluminum-induced dreierketten chain cross-links increase the mechanical properties of nanocrystalline calcium aluminosilicate hydrate

    PubMed Central

    Geng, Guoqing; Myers, Rupert J.; Li, Jiaqi; Maboudian, Roya; Carraro, Carlo; Shapiro, David A.; Monteiro, Paulo J. M.

    2017-01-01

    The incorporation of Al and increased curing temperature promotes the crystallization and cross-linking of calcium (alumino)silicate hydrate (C-(A-)S-H), which is the primary binding phase in most contemporary concrete materials. However, the influence of Al-induced structural changes on the mechanical properties at atomistic scale is not well understood. Herein, synchrotron radiation-based high-pressure X-ray diffraction is used to quantify the influence of dreierketten chain cross-linking on the anisotropic mechanical behavior of C-(A-)S-H. We show that the ab-planar stiffness is independent of dreierketten chain defects, e.g. vacancies in bridging tetrahedra sites and Al for Si substitution. The c-axis of non-cross-linked C-(A-)S-H is more deformable due to the softer interlayer opening but stiffens with decreased spacing and/or increased zeolitic water and Ca2+ of the interlayer. Dreierketten chain cross-links act as ‘columns’ to resist compression, thus increasing the bulk modulus of C-(A-)S-H. We provide the first experimental evidence on the influence of the Al-induced atomistic configurational change on the mechanical properties of C-(A-)S-H. Our work advances the fundamental knowledge of C-(A-)S-H on the lowest level of its hierarchical structure, and thus can impact the way that innovative C-(A-)S-H-based cementitious materials are developed using a ‘bottom-up’ approach. PMID:28281635

  11. Modeled Neutron and Charged-Particle Induced Nuclear Reaction Cross Sections for Radiochemistry in the Region of Yttrium, Zirconium, Niobium, and Molybdenum

    SciTech Connect

    Hoffman, R D; Kelley, K; Dietrich, F S; Bauer, R; Mustafa, M G

    2006-06-13

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron, proton, and deuteron induced nuclear reaction cross sections for targets ranging from strontium (Z = 38) to rhodium (Z = 45).

  12. A novel, visible light-induced, rapidly cross-linkable gelatin scaffold for osteochondral tissue engineering

    PubMed Central

    Mazaki, Tetsuro; Shiozaki, Yasuyuki; Yamane, Kentaro; Yoshida, Aki; Nakamura, Mariko; Yoshida, Yasuhiro; Zhou, Di; Kitajima, Takashi; Tanaka, Masato; Ito, Yoshihiro; Ozaki, Toshifumi; Matsukawa, Akihiro

    2014-01-01

    Osteochondral injuries remain difficult to repair. We developed a novel photo-cross-linkable furfurylamine-conjugated gelatin (gelatin-FA). Gelatin-FA was rapidly cross-linked by visible light with Rose Bengal, a light sensitizer, and was kept gelled for 3 weeks submerged in saline at 37°C. When bone marrow-derived stromal cells (BMSCs) were suspended in gelatin-FA with 0.05% Rose Bengal, approximately 87% of the cells were viable in the hydrogel at 24 h after photo-cross-linking, and the chondrogenic differentiation of BMSCs was maintained for up to 3 weeks. BMP4 fusion protein with a collagen binding domain (CBD) was retained in the hydrogels at higher levels than unmodified BMP4. Gelatin-FA was subsequently employed as a scaffold for BMSCs and CBD-BMP4 in a rabbit osteochondral defect model. In both cases, the defect was repaired with articular cartilage-like tissue and regenerated subchondral bone. This novel, photo-cross-linkable gelatin appears to be a promising scaffold for the treatment of osteochondral injury. PMID:24662725

  13. Determination of Resonance Parameters and their Covariances from Neutron Induced Reaction Cross Section Data

    SciTech Connect

    Schillebeeckx, P.; Becker, B.; Danon, Y.; Guber, K.; Harada, H.; Heyse, J.; Junghans, A.R.; Kopecky, S.; Massimi, C.; Moxon, M.C.; Otuka, N.; Sirakov, I.; Volev, K.

    2012-12-15

    Cross section data in the resolved and unresolved resonance region are represented by nuclear reaction formalisms using parameters which are determined by fitting them to experimental data. Therefore, the quality of evaluated cross sections in the resonance region strongly depends on the experimental data used in the adjustment process and an assessment of the experimental covariance data is of primary importance in determining the accuracy of evaluated cross section data. In this contribution, uncertainty components of experimental observables resulting from total and reaction cross section experiments are quantified by identifying the metrological parameters involved in the measurement, data reduction and analysis process. In addition, different methods that can be applied to propagate the covariance of the experimental observables (i.e. transmission and reaction yields) to the covariance of the resonance parameters are discussed and compared. The methods being discussed are: conventional uncertainty propagation, Monte Carlo sampling and marginalization. It is demonstrated that the final covariance matrix of the resonance parameters not only strongly depends on the type of experimental observables used in the adjustment process, the experimental conditions and the characteristics of the resonance structure, but also on the method that is used to propagate the covariances. Finally, a special data reduction concept and format is presented, which offers the possibility to store the full covariance information of experimental data in the EXFOR library and provides the information required to perform a full covariance evaluation.

  14. DNA vaccine expressing the mimotope of GD2 ganglioside induces protective GD2 cross-reactive antibody responses.

    PubMed

    Bolesta, Elizabeth; Kowalczyk, Aleksandra; Wierzbicki, Andrzej; Rotkiewicz, Piotr; Bambach, Barbara; Tsao, Chun-Yen; Horwacik, Irena; Kolinski, Andrzej; Rokita, Hanna; Brecher, Martin; Wang, Xinhui; Ferrone, Soldano; Kozbor, Danuta

    2005-04-15

    The GD2 ganglioside expressed on neuroectodermally derived tumors, including neuroblastoma and melanoma, is weakly immunogenic in tumor-bearing patients and induces predominantly immunoglobulin (Ig)-M antibody responses in the immunized host. Here, we investigated whether interconversion of GD2 into a peptide mimetic form would induce GD2 cross-reactive IgG antibody responses in mice. Screening of the X(15) phage display peptide library with the anti-GD2 monoclonal antibody (mAb) 14G2a led to isolation of mimetic peptide 47, which inhibited the binding of 14G2a antibody to GD2-positive tumor cells. The peptide was also recognized by GD2-specific serum antibodies from a patient with neuroblastoma, suggesting that it bears an internal image of GD2 ganglioside expressed on the tumor cells. The molecular basis for antigenicity of the GD2 mimetic peptide, established by molecular modeling and mutagenesis studies, led to the generation of a 47-LDA mutant with an increased mimicry to GD2. Immunization of mice with peptide 47-LDA-encoded plasmid DNA elicited GD2 cross-reactive IgG antibody responses, which were increased on subsequent boost with GD2 ganglioside. The vaccine-induced antibodies recognized GD2-positive tumor cells, mediated complement-dependent cytotoxicity, and exhibited protection against s.c. human GD2-positive melanoma growth in the severe combined immunodeficient mouse xenograft model. The results from our studies provide insights into approaches for boosting GD2 cross-reactive IgG antibody responses by minigene vaccination with a protective epitope of GD2 ganglioside.

  15. Inducing Efficient Cross-priming Using Antigen-coated Yeast Particles

    PubMed Central

    Howland, Shanshan W.; Tsuji, Takemasa; Gnjatic, Sacha; Ritter, Gerd; Old, Lloyd J.; Wittrup, Karl Dane

    2009-01-01

    Summary Saccharomyces cerevisiae stimulates dendritic cells (DCs) and represents a promising candidate for cancer vaccine development. Effective cross-presentation of antigen delivered to DCs is necessary for successful induction of cellular immunity. Here, we present a yeast-based vaccine approach that is independent of yeast’s ability to express the chosen antigen, which is instead produced separately and conjugated to the yeast cell wall. The conjugation method is site-specific (based on the SNAP-tag) and designed to facilitate antigen release in the DC phagosome and subsequent translocation for cross-presentation. We demonstrate that nonsite-specific chemical conjugation of the same protein hinders cross-presentation. Phagosomal antigen release was further expedited through the insertion of the invariant chain ectodomain as a linker, which is rapidly cleaved by Cathepsin S. The dose of delivered antigen was increased in several ways: by using yeast strains with higher surface amine densities, by using yeast hulls (cell wall fragments) instead of whole cells, and by conjugating multiple layers of antigen. The novel multilayer conjugation scheme takes advantage of Sfp phosphopantetheinyl transferase and remains site-specific; it enables the antigen dose to grow linearly with the number of layers. We show that whole yeast cells coated with 1 layer of the cancer-testis antigen NY-ESO-1 and yeast hulls bearing 3 layers were able to cross-prime naive CD8+ T cells in vitro, with the latter resulting in higher frequencies of antigen-specific cells after 10 days. This cross-presentation-efficient antigen conjugation scheme is not limited to yeast and can readily be applied toward the development of other particulate vaccines. PMID:18600183

  16. A visually-induced eyelid droop illusion as a classroom demonstration of cross-modality.

    PubMed

    Wolfe, Uta

    2010-01-01

    Cross-modality, or the interaction between the different senses, has emerged as a fundamental concept in perceptual neuroscience and psychology. The traditional idea of five separate senses with independent neural substrates has been invalidated by both psychophysical findings of sensory integration and neurophysiological discoveries of multi-modal neurons in many areas of the brain. Even areas previously thought to be unimodal have been shown to be influenced by other senses, thus establishing multisensory integration as a key principle of perceptual neuroscience. There are several obstacles to students' understanding of the concept. First, everyday subjective experience is modal: one sees, hears, smells the world and is rarely aware that these seemingly separate impressions are in reality fully integrated with each other. Second, standard content in undergraduate classes and textbooks still emphasizes the modal model of the senses and their corresponding brain areas and rarely mentions cross-modal phenomena. Third, feasible classroom demonstrations of cross-modality are few, making it difficult to provide students with first-hand experience that would aid their understanding of the principle. This article describes an accessible and effective classroom demonstration of cross-modality between low-level vision, touch and proprioception. It consists in the illusion of eyelid droop in one eye when the other eye has been dark-adapted and when both eyes are exposed to the dark. The perceptual effect is dramatic and reliable. It illustrates cross-modality at a fundamental level of perception and might provide a means to help integrate the teaching of the concept into the standard content of undergraduate classes.

  17. Two-dimensional electromagnetically induced cross-grating in a four-level N-type atomic system

    NASA Astrophysics Data System (ADS)

    Wu, Jianchun; Ai, Baoquan

    2015-06-01

    We propose a scheme for a two-dimensional (2D) electromagnetically induced cross-grating (EICG) in a four-level N-type atomic system. By employing standing-wave fields interacting with the atomic system, the absorption and dispersion of the probe field will change with the spatial periodical modulation. The first-order diffraction intensity sensitively depends on the parameters (the probe detuning, and the amplitude and detuning of the standing-wave fields), and can reach its maximum on varying the system parameters. The present studies may be instructive to design new devices in all-optical switching and optical imaging.

  18. Observation of structure in laser-induced Penning and associative ionization in crossed-beam Na+Na collisions

    SciTech Connect

    Polak-Dingels, P.; Delpech, J.; Weiner, J.

    1980-06-23

    The results of double-laser experiments in which Na/sup +//sub 2/ and Na/sup +/ are produced in crossed-alkali beams under single-collision conditions in the presence of strong optical fields are reported. Structure in the mass-selected product ion intensity as a function laser frequency is observed when the optical field is strongly focused and tuned far off atomic or dimer transitions. These measurements are the first to show that nuclear motion of the quasimolecular collision intermediate plays an important role in laser-induced collisional ionization.

  19. Mass spectrometric identification of formaldehyde-induced peptide modifications under in vivo protein cross-linking conditions.

    PubMed

    Toews, Judy; Rogalski, Jason C; Clark, Thomas J; Kast, Juergen

    2008-06-23

    Formaldehyde cross-linking of proteins is emerging as a novel approach to study protein-protein interactions in living cells. It has been shown to be compatible with standard techniques used in functional proteomics such as affinity-based protein enrichment, enzymatic digestion, and mass spectrometric protein identification. So far, the lack of knowledge on formaldehyde-induced protein modifications and suitable mass spectrometric methods for their targeted detection has impeded the identification of the different types of cross-linked peptides in these samples. In particular, it has remained unclear whether in vitro studies that identified a multitude of amino acid residues reacting with formaldehyde over the course of several days are suitable substitutes for the much shorter reaction times of 10-20 min used in cross-linking experiments in living cells. The current study on model peptides identifies amino-termini as well as lysine, tryptophan, and cysteine side chains, i.e. a small subset of those modified after several days, as the major reactive sites under such conditions, and suggests relative position in the peptide sequence as well as sequence microenvironment to be important factors that govern reactivity. Using MALDI-MS, mass increases of 12 Da on amino groups and 30 Da on cysteines were detected as the major reaction products, while peptide fragment ion analysis by tandem mass spectrometry was used to localize the actual modification sites on a peptide. Non-specific cross-linking was absent, and could only be detected with low yield at elevated peptide concentrations. The detailed knowledge on the constraints and products of the formaldehyde reaction with peptides after short incubation times presented in this study is expected to facilitate the targeted mass spectrometric analysis of proteins after in vivo formaldehyde cross-linking.

  20. Measurement of Neutrino Induced Inclusive Delta Resonance Cross section in NOMAD

    NASA Astrophysics Data System (ADS)

    Kullenberg, Chris; Kim, Jae

    2007-04-01

    The measurement of neutrino induced inclusive Resonance interaction process in NOMAD will be discussed. The signature of a νμ induced resonance off a neutron target results in a -circ with ++circ (1230) resonance; the ++circ decays into a proton and a pion (two positive hadrons). A likelihood method was used to separate the signal from background (+- hadron pairs). The measurement technique and the preliminary results will be presented.

  1. Extension of activation cross section data of deuteron induced nuclear reactions on rhodium up to 50 MeV

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Tárkányi, F.; Takács, S.; Ditrói, F.

    2015-11-01

    In the frame of the systematical study of light ion induced nuclear reactions activation cross sections for deuteron induced reactions on monoisotopic 103Rh were extended to 50 MeV incident energy. Excitation functions were measured in the 49.8-36.6 MeV energy range for the 103Rh(d,xn)100,101Pd, 103Rh(d,pxn)99m,99g,100,101m,101g,102m,102gRh and 103Rh(d,x)97,103Ru reactions by using the stacked foil irradiation technique and off-line high resolution γ-ray spectrometry. The experimental results are compared to our previous results and to the theoretical predictions in the TENDL-2014 library (TALYS 1.6 code).

  2. Volumetric Deformation of Live Cells Induced by Pressure-Activated Cross-Membrane Ion Transport

    NASA Astrophysics Data System (ADS)

    Hui, T. H.; Zhou, Z. L.; Qian, J.; Lin, Y.; Ngan, A. H. W.; Gao, H.

    2014-09-01

    In this work, we developed a method that allows precise control over changes in the size of a cell via hydrostatic pressure changes in the medium. Specifically, we show that a sudden increase, or reduction, in the surrounding pressure, in the physiologically relevant range, triggers cross-membrane fluxes of sodium and potassium ions in leukemia cell lines K562 and HL60, resulting in reversible volumetric deformation with a characteristic time of around 30 min. Interestingly, healthy leukocytes do not respond to pressure shocks, suggesting that the cancer cells may have evolved the ability to adapt to pressure changes in their microenvironment. A model is also proposed to explain the observed cell deformation, which highlights how the apparent viscoelastic response of cells is governed by the microscopic cross-membrane transport.

  3. Induced Bacterial Cross-Resistance toward Host Antimicrobial Peptides: A Worrying Phenomenon

    PubMed Central

    Fleitas, Osmel; Franco, Octávio L.

    2016-01-01

    Bacterial resistance to conventional antibiotics has reached alarming levels, threatening to return to the pre-antibiotic era. Therefore, the search for new antimicrobial compounds that overcome the resistance phenomenon has become a priority. Antimicrobial peptides (AMPs) appear as one of the most promising antibiotic medicines. However, in recent years several AMP-resistance mechanisms have been described. Moreover, the AMP-resistance phenomenon has become more complex due to its association with cross-resistance toward AMP effectors of the host innate immune system. In this context, the use of AMPs as a therapeutic option could be potentially hazardous, since bacteria could develop resistance toward our innate immune system. Here, we review the findings of major studies that deal with the AMP cross-resistance phenomenon. PMID:27047486

  4. New Neutron-Induced Cross-Section Measurements for Weak s-process Studies

    SciTech Connect

    Guber, Klaus H; Wiarda, Dorothea; Leal, Luiz C; Derrien, Herve; Ausmus, Clint; Brashear, Dane; White, John A

    2008-01-01

    A series of new neutron capture and transmission measurements has been undertaken at the Oak Ridge Electron Linear Accelerator (ORELA) in response to deficiencies identified in nuclear data libraries of crucial importance to the Nuclear Criticality Safety Program. New data and evaluations including covariances are required for several stable fission products as well as for materials found in mixtures with uranium. For example, chromium and nickel as constituents of stainless steel perform poorly in criticality calculations due to their relatively large neutron cross sections and substantial uncertainties in previous measurements. Therefore, new neutron-capture and total cross-section measurements are needed for 52,53Cr and 58,60Ni. These newly obtained data can be used not only to improve criticality calculations but also to serve as input parameters for the weak s-process stellar model calculations in massive stars. We will report on new experiments for these nuclides.

  5. Cross sections, momentum distributions, and neutron angular distributions for 11Be induced reactions on silicon

    NASA Astrophysics Data System (ADS)

    Negoita, F.; Borcea, C.; Carstoiu, F.; Lewitowicz, M.; Saint-Laurent, M. G.; Anne, R.; Guillemaud-Mueller, D.; Mueller, A. C.; Pougheon, F.; Sorlin, O.; Fomitchev, A.; Lukyanov, S.; Penionzhkevich, Yu.; Skobelev, N.; Dlouhy, Z.

    1999-04-01

    The halo neutron breakup cross section for 11Be on Si has been obtained in a wide energy range by applying an integral method and separately determining the contributions of stripping and dissociation mechanisms. A new breakup mechanism, for which the core energy is strongly dumped, has also been observed. Parallel momentum distributions of 10Be resulting from breakup have been deduced for both stripping and dissociation and angular and energy distributions of the neutrons coincident with different reaction products have been measured. Charge changing cross sections for 10,11Be complemented the measurements. An extended Glauber model has been elaborated in order to provide a unitary interpretation for all the data. It takes into account both the specific structure of 11Be and the reaction mechanism, practically without free parameters. The effects of reaction mechanisms on the widths of observed momentum distributions are particularly important.

  6. Induced Bacterial Cross-Resistance toward Host Antimicrobial Peptides: A Worrying Phenomenon.

    PubMed

    Fleitas, Osmel; Franco, Octávio L

    2016-01-01

    Bacterial resistance to conventional antibiotics has reached alarming levels, threatening to return to the pre-antibiotic era. Therefore, the search for new antimicrobial compounds that overcome the resistance phenomenon has become a priority. Antimicrobial peptides (AMPs) appear as one of the most promising antibiotic medicines. However, in recent years several AMP-resistance mechanisms have been described. Moreover, the AMP-resistance phenomenon has become more complex due to its association with cross-resistance toward AMP effectors of the host innate immune system. In this context, the use of AMPs as a therapeutic option could be potentially hazardous, since bacteria could develop resistance toward our innate immune system. Here, we review the findings of major studies that deal with the AMP cross-resistance phenomenon.

  7. Adaptive immunity to leukemia is inhibited by cross-reactive induced regulatory T cells

    PubMed Central

    Manlove, Luke S.; Berquam-Vrieze, Katherine E.; Pauken, Kristen E.; Williams, Richard T.; Jenkins, Marc K.; Farrar, Michael A.

    2015-01-01

    BCR-ABL+ acute lymphoblastic leukemia patients have transient responses to current therapies. However, the fusion of BCR to ABL generates a potential leukemia-specific antigen that could be a target for immunotherapy. We demonstrate that the immune system can limit BCR-ABL+ leukemia progression although ultimately this immune response fails. To address how BCR-ABL+ leukemia escapes immune surveillance, we developed a peptide: MHC-II tetramer that labels endogenous BCR-ABL-specific CD4+ T cells. Naïve mice harbored a small population of BCR-ABL-specific T cells that proliferated modestly upon immunization. The small number of naïve BCR-ABL specific T cells was due to negative selection in the thymus, which depleted BCR-ABL specific T cells. Consistent with this observation, we saw that BCR-ABL specific T cells were cross-reactive with an endogenous peptide derived from ABL. Despite this cross-reactivity, the remaining population of BCR-ABL reactive T cells proliferated upon immunization with the BCR-ABL fusion peptide and adjuvant. In response to BCR-ABL+ leukemia, BCR-ABL specific T cells proliferated and converted into regulatory T cells (Treg cells), a process that was dependent on cross-reactivity with self-antigen, TGFβ1, and MHC-II antigen presentation by leukemic cells. Treg cells were critical for leukemia progression in C57Bl/6 mice, as transient Treg cell ablation led to extended survival of leukemic mice. Thus, BCR-ABL+ leukemia actively suppresses anti-leukemia immune responses by converting cross-reactive leukemia-specific T cells into Treg cells. PMID:26378075

  8. Disorder induced in nonoverlap myosin cross-bridges by loss of adenosine triphosphate.

    PubMed Central

    Padrón, R; Craig, R

    1989-01-01

    Adenosine triphosphate-dependent changes in myosin filament structure have been directly observed in whole muscle by electron microscopy of thin sections of rapidly frozen, demembranated frog sartorius specimens. In the presence of ATP the thick filaments show an ordered, helical array of cross-bridges except in the bare zone. In the absence of ATP they show two distinct appearances: in the region of overlap with actin, there is an ordered, rigorlike array of cross-bridges between the thick and thin filaments, whereas in the nonoverlap region (H-zone) the myosin heads move away from the thick filament backbone and lose their helical order. This result suggests that the presence of ATP is necessary for maintenance of the helical array of cross-bridges characteristic of the relaxed state. The primary effect of ATP removal on the myosin heads appears to be weaken their binding to the thick filament backbone; released heads that are close to an actin filament subsequently form a new actin-based, ordered array. Images FIGURE 1 FIGURE 2 PMID:2605303

  9. Measurement of neutrino induced charged current neutral pion production cross section at SciBooNE

    SciTech Connect

    Catala-Perez, Juan

    2014-01-01

    SciBooNE is a neutrino scattering experiment located in the Booster Neutrino Beam at Fermilab. It collected data from June 2007 to August 2008 to accurately measure muon neutrino and anti-neutrino cross sections on carbon around 1 GeV neutrino energy. In this thesis we present the results on the measurement of the muon neutrino cross section resulting in a μ- plus a single π0 final state (CC- π0 channel). The present work will show the steps taken to achieve this result: from the reconstruction improvements to the background extraction. The flux-averaged CC - π0 production cross section measurement obtained in this thesis < σCC- π0 > Φ = (5.6 ± 1.9fit ± 0.7beam ± 0.5int - 0.7det) × 10-40 cm2/N at an average energy of 0.89 GeV is found to agree well both with the expectation from the Monte Ca

  10. Concussion induces gait inter-joint coordination variability under conditions of divided attention and obstacle crossing.

    PubMed

    Chiu, Shiu-Ling; Osternig, Louis; Chou, Li-Shan

    2013-09-01

    This study investigated the effect of concussion on the pattern and variability of inter-joint coordination during level walking (Level), obstacle crossing (OB), and walking with a concurrent cognitive test (ATT). Gait analyses of 23 concussed and 23 matched healthy adults were performed. Continuous relative phase (CRP), derived from phase angles of two adjacent joints, was used to assess inter-joint coordination. Cross-correlation measures and root-mean-square (RMS) differences were used to compare CRP patterns of the Level condition to those of OB and ATT conditions, respectively. Deviation phase (DP) was used to evaluate variability of inter-joint coordination for each task. For hip-knee and knee-ankle CRP patterns, RMS differences between OB and Level and between ATT and Level in concussed subjects were significantly greater than those of healthy adults. No significant group differences were detected for the cross-correlation measures of hip-knee and knee-ankle CRP patterns. In stance phase, a significant task effect on DP values was detected in hip-knee inter-joint coordination. For knee-ankle inter-joint coordination, concussed subjects showed significantly greater DP values than healthy controls during OB and ATT. In swing phase, concussed individuals showed greater DP values in hip-knee and knee-ankle inter-joint coordination compared to healthy controls. The findings suggest that the ability to modulate inter-joint coordination patterns when accommodating to gait perturbations is affected by concussion.

  11. Trauma-induced changes in diaphyseal cross-sectional geometry in two elites from Copan, Honduras.

    PubMed

    Nystrom, Kenneth C; Buikstra, Jane E

    2005-12-01

    This research utilized biplanar radiographs to estimate cross-sectional biomechanical properties for the skeletal remains of two elite individuals from the Early Classic period (ca. AD 400-600) of Copan, Honduras: K'inich Yax K'uk' Mo' (Hunal Burial 95-2), founder of the Early Classic Dynasty at Copan, and the primary female interment (Burial 37-8) from the Motmot tomb. Both individuals survived severe blunt-force insults to the right forearm. Gross skeletal examination and evaluation of the radiographs for K'inich Yax K'uk' Mo' suggest that these traumas resulted from, at least in part, disuse atrophy of the affected forearm skeletal elements. Gross and radiologic evaluation of the Motmot remains countered the possibility that she suffered from a metabolic bone disease, and confirmed the presence of a well-healed parry fracture of the right ulna. The degree of asymmetry in cross-sectional biomechanical properties reported here for K'inich Yax K'uk' Mo' is likely the secondary result of the described blunt-force trauma. The results obtained for the principal Motmot interment are not as dramatic, but suggest subtle changes to humeral cross-sectional geometry subsequent to trauma.

  12. Targeting the gut vascular endothelium induces gut effector CD8 T cell responses via cross-presentation by dendritic cells.

    PubMed

    Bourges, Dorothee; Zhan, Yifan; Brady, Jamie L; Braley, Hal; Caminschi, Irina; Prato, Sandro; Villadangos, José A; Lew, Andrew M

    2007-11-01

    Systemic delivery of Ag usually induces poor mucosal immunity. To improve the CD8 T cell response at mucosal sites, we targeted the Ag to MAdCAM-1, a mucosal addressin cell adhesion molecule expressed mainly by high endothelial venules (HEV) in mesenteric lymph nodes (MLN) and Peyer's patches of gut-associated lymphoid tissue. When chemical conjugates of anti-MAdCAM-1 Ab and model Ag OVA were injected i.v., a greatly enhanced proliferative response of Ag-specific OT-I CD8 T cells was detected in MLN. This was preceded by prolonged accumulation, up to 2 wk, of the anti-MAdCAM OVA conjugate on HEV of Peyer's patches and MLN. In contrast, nontargeted OVA conjugate was very inefficient in inducing OT-I CD8 T cell proliferation in MLN and required at least 20-fold more Ag to induce a comparable response. In addition, MAdCAM targeting elicits an endogenous OVA-specific CD8 T cell response, evident by IFN-gamma production and target killing. Induced response offers protection against an OVA-expressing B cell lymphoma. We propose that the augmentation of gut CD8 T cell responses by MAdCAM targeting is due to both accumulation of Ag in the HEV and conversion of a soluble Ag to a cell-associated one, allowing cross-presentation by DCs.

  13. Spermidine-induced improvement of memory involves a cross-talk between protein kinases C and A.

    PubMed

    Guerra, Gustavo P; Mello, Carlos F; Bochi, Guilherme V; Pazini, Andréia M; Rosa, Michelle M; Ferreira, Juliano; Rubin, Maribel A

    2012-07-01

    Spermidine (SPD) is an endogenous aliphatic amine with polycationic structure that modulates NMDA receptor activity and improves memory. Recent evidence suggests that cAMP-dependent protein kinase (PKA) and cAMP response element-binding protein (CREB) play a role in SPD-induced improvement of memory. In the current study, we determined whether the calcium-dependent protein kinase (PKC) signaling pathway is involved in SPD-induced facilitation of memory of inhibitory avoidance task in adult rats. The post-training administration of the PKC inhibitor, 3-[1-(dimethylaminopropyl)indol-3-yl]-4-(indol-3-yl)maleimide hydrochloride [GF 109203X, 2.5 ρmol, intrahippocampal (ih)] with SPD (0.2 nmol, ih) prevented memory improvement induced by SPD. Intrahippocampal administration of SPD (0.2 nmol) facilitated PKC phosphorylation in the hippocampus, 30 min after administration. GF 109203X prevented not only the stimulatory effect of SPD on PKC but also PKA and CREB phosphorylation. These results suggest that memory enhancement induced by the ih administration of SPD involves the cross-talk between PKC and PKA/CREB, with sequential activation of PKC and PKA/CREB pathways, in rats.

  14. HIV-1 VACCINES. Diversion of HIV-1 vaccine-induced immunity by gp41-microbiota cross-reactive antibodies.

    PubMed

    Williams, Wilton B; Liao, Hua-Xin; Moody, M Anthony; Kepler, Thomas B; Alam, S Munir; Gao, Feng; Wiehe, Kevin; Trama, Ashley M; Jones, Kathryn; Zhang, Ruijun; Song, Hongshuo; Marshall, Dawn J; Whitesides, John F; Sawatzki, Kaitlin; Hua, Axin; Liu, Pinghuang; Tay, Matthew Z; Seaton, Kelly E; Shen, Xiaoying; Foulger, Andrew; Lloyd, Krissey E; Parks, Robert; Pollara, Justin; Ferrari, Guido; Yu, Jae-Sung; Vandergrift, Nathan; Montefiori, David C; Sobieszczyk, Magdalena E; Hammer, Scott; Karuna, Shelly; Gilbert, Peter; Grove, Doug; Grunenberg, Nicole; McElrath, M Juliana; Mascola, John R; Koup, Richard A; Corey, Lawrence; Nabel, Gary J; Morgan, Cecilia; Churchyard, Gavin; Maenza, Janine; Keefer, Michael; Graham, Barney S; Baden, Lindsey R; Tomaras, Georgia D; Haynes, Barton F

    2015-08-14

    An HIV-1 DNA prime vaccine, with a recombinant adenovirus type 5 (rAd5) boost, failed to protect from HIV-1 acquisition. We studied the nature of the vaccine-induced antibody (Ab) response to HIV-1 envelope (Env). HIV-1-reactive plasma Ab titers were higher to Env gp41 than to gp120, and repertoire analysis demonstrated that 93% of HIV-1-reactive Abs from memory B cells responded to Env gp41. Vaccine-induced gp41-reactive monoclonal antibodies were non-neutralizing and frequently polyreactive with host and environmental antigens, including intestinal microbiota (IM). Next-generation sequencing of an immunoglobulin heavy chain variable region repertoire before vaccination revealed an Env-IM cross-reactive Ab that was clonally related to a subsequent vaccine-induced gp41-reactive Ab. Thus, HIV-1 Env DNA-rAd5 vaccine induced a dominant IM-polyreactive, non-neutralizing gp41-reactive Ab repertoire response that was associated with no vaccine efficacy. Copyright © 2015, American Association for the Advancement of Science.

  15. Psoralen-induced DNA interstrand cross-links block transcription and induce p53 in an ataxia-telangiectasia and rad3-related-dependent manner.

    PubMed

    Derheimer, Frederick A; Hicks, J Kevin; Paulsen, Michelle T; Canman, Christine E; Ljungman, Mats

    2009-03-01

    Psoralen plus UVA light (PUVA) is commonly used to treat psoriasis, a common skin disorder associated with rapid proliferation of cells. PUVA exerts its antiproliferative activity through formation of DNA monoadducts and interstrand cross-links (ICLs). However, this treatment may lead to skin malignancies as a direct result of inducing carcinogenic DNA damage. Inactivation of the p53 tumor suppressor gene is an important event in the development of skin cancer. p53 is rapidly phosphorylated and stabilized in response to DNA damage, and the induction of apoptosis by p53 is an important mechanism by which p53 exerts its tumor-suppressive activity. To better understand the mechanism by which PUVA treatment induces p53, we exposed human skin fibroblasts with PUVA under conditions that differentially produce monoadducts and ICLs and found that psoralen-induced ICLs induced phosphorylation of the Ser-15 site of p53 and apoptosis much more effectively than psoralen-induced monoadducts. The induction of p53 phosphorylation by psoralen ICLs did not require factors believed to be involved in the repair of psoralen ICLs [xeroderma pigmentosum (XP)-A, XP-C, XP-F, Cockayne's syndrome-B, Fanconi anemia] but did require the ataxia-telangiectasia and Rad3-related but not the ataxia-telangiectasia mutated kinase. Psoralen-induced ICLs blocked transcription and replication more efficiently than monoadducts, and induction of p53 and apoptosis correlated with doses causing interference with transcription rather than DNA replication. Our finding that cells underwent apoptosis preferentially during S-phase suggests that the combined blockade of transcription and DNA replication by psoralen ICLs during S-phase elicits a strong apoptotic response.

  16. TRIF promotes angiotensin II-induced cross-talk between fibroblasts and macrophages in atrial fibrosis

    SciTech Connect

    Chen, Xiao-Qing; Zhang, Dao-Liang; Zhang, Ming-Jian; Guo, Meng; Zhan, Yang-Yang; Liu, Fang; Jiang, Wei-Feng; Zhou, Li; Zhao, Liang; Wang, Quan-Xing; Liu, Xu

    2015-08-14

    Aims: Atrial fibroblasts and macrophages have long been thought to participate in atrial fibrillation (AF). However, which specific mediator may regulate the interaction between them remains unclear. Methods and results: We provided the evidence for the involvement of Toll/IL-1 receptor domain-containing adaptor inducing IFN-β (TRIF), an important inflammation-related molecule, in the pathophysiology of AF. Patients with AF showed higher levels of angiotensin II (AngII) and TRIF expression and larger number of macrophages infiltration in left atria appendage than individuals with sinus rhythm (SR). In the cell study, AngII induced chemokines expressions in mouse atrial fibroblasts and AngII-stimulated atrial fibroblasts induced the chemotaxis of macrophages, which were reduced by losartan and TRIF siRNA. Meanwhile, AngII-stimulated atrial fibroblasts proliferation was enhanced by macrophages. Conclusions: Our data demonstrated that TRIF may be a crucial factor promoting the interaction between atrial fibroblasts and macrophages, leading to atrial fibrosis. - Highlights: • Compared with SR, AF showed higher TRIF expression in left atrial appendage. • TRIF siRNA reversed macrophage chemotaxis induced by AngII-treated fibroblast. • TRIF siRNA reversed chemokines expressions induced by AngII in fibroblast. • AngII-stimulated atrial fibroblast proliferation was enhanced by macrophage.

  17. Field-induced superconducting phase of FeSe in the BCS-BEC cross-over.

    PubMed

    Kasahara, Shigeru; Watashige, Tatsuya; Hanaguri, Tetsuo; Kohsaka, Yuhki; Yamashita, Takuya; Shimoyama, Yusuke; Mizukami, Yuta; Endo, Ryota; Ikeda, Hiroaki; Aoyama, Kazushi; Terashima, Taichi; Uji, Shinya; Wolf, Thomas; von Löhneysen, Hilbert; Shibauchi, Takasada; Matsuda, Yuji

    2014-11-18

    Fermi systems in the cross-over regime between weakly coupled Bardeen-Cooper-Schrieffer (BCS) and strongly coupled Bose-Einstein-condensate (BEC) limits are among the most fascinating objects to study the behavior of an assembly of strongly interacting particles. The physics of this cross-over has been of considerable interest both in the fields of condensed matter and ultracold atoms. One of the most challenging issues in this regime is the effect of large spin imbalance on a Fermi system under magnetic fields. Although several exotic physical properties have been predicted theoretically, the experimental realization of such an unusual superconducting state has not been achieved so far. Here we show that pure single crystals of superconducting FeSe offer the possibility to enter the previously unexplored realm where the three energies, Fermi energy εF, superconducting gap Δ, and Zeeman energy, become comparable. Through the superfluid response, transport, thermoelectric response, and spectroscopic-imaging scanning tunneling microscopy, we demonstrate that εF of FeSe is extremely small, with the ratio Δ/εF ~ 1(~0.3) in the electron (hole) band. Moreover, thermal-conductivity measurements give evidence of a distinct phase line below the upper critical field, where the Zeeman energy becomes comparable to εF and Δ. The observation of this field-induced phase provides insights into previously poorly understood aspects of the highly spin-polarized Fermi liquid in the BCS-BEC cross-over regime.

  18. Murine Langerin+ dermal dendritic cells prime CD8+ T cells while Langerhans cells induce cross-tolerance

    PubMed Central

    Flacher, Vincent; Tripp, Christoph H; Mairhofer, David G; Steinman, Ralph M; Stoitzner, Patrizia; Idoyaga, Juliana; Romani, Nikolaus

    2014-01-01

    Skin dendritic cells (DCs) control the immunogenicity of cutaneously administered vaccines. Antigens targeted to DCs via the C-type lectin Langerin/CD207 are cross-presented to CD8+ T cells in vivo. We investigated the relative roles of Langerhans cells (LCs) and Langerin+ dermal DCs (dDCs) in different vaccination settings. Poly(I:C) and anti-CD40 agonist antibody promoted cytotoxic responses upon intradermal immunization with ovalbumin (OVA)-coupled anti-Langerin antibodies (Langerin/OVA). This correlated with CD70 upregulation in Langerin+ dDCs, but not LCs. In chimeric mice where Langerin targeting was restricted to dDCs, CD8+ T-cell memory was enhanced. Conversely, providing Langerin/OVA exclusively to LCs failed to prime cytotoxicity, despite initial antigen cross-presentation to CD8+ T cells. Langerin/OVA combined with imiquimod could not prime CD8+ T cells and resulted in poor cytotoxicity in subsequent responses. This tolerance induction required targeting and maturation of LCs. Altogether, Langerin+ dDCs prime long-lasting cytotoxic responses, while cross-presentation by LCs negatively influences CD8+ T-cell priming. Moreover, this highlights that DCs exposed to TLR agonists can still induce tolerance and supports the existence of qualitatively different DC maturation programs. PMID:25085878

  19. Field-induced superconducting phase of FeSe in the BCS-BEC cross-over

    PubMed Central

    Kasahara, Shigeru; Watashige, Tatsuya; Hanaguri, Tetsuo; Kohsaka, Yuhki; Yamashita, Takuya; Shimoyama, Yusuke; Mizukami, Yuta; Endo, Ryota; Ikeda, Hiroaki; Aoyama, Kazushi; Terashima, Taichi; Uji, Shinya; Wolf, Thomas; von Löhneysen, Hilbert; Shibauchi, Takasada; Matsuda, Yuji

    2014-01-01

    Fermi systems in the cross-over regime between weakly coupled Bardeen–Cooper–Schrieffer (BCS) and strongly coupled Bose–Einstein-condensate (BEC) limits are among the most fascinating objects to study the behavior of an assembly of strongly interacting particles. The physics of this cross-over has been of considerable interest both in the fields of condensed matter and ultracold atoms. One of the most challenging issues in this regime is the effect of large spin imbalance on a Fermi system under magnetic fields. Although several exotic physical properties have been predicted theoretically, the experimental realization of such an unusual superconducting state has not been achieved so far. Here we show that pure single crystals of superconducting FeSe offer the possibility to enter the previously unexplored realm where the three energies, Fermi energy εF, superconducting gap Δ, and Zeeman energy, become comparable. Through the superfluid response, transport, thermoelectric response, and spectroscopic-imaging scanning tunneling microscopy, we demonstrate that εF of FeSe is extremely small, with the ratio Δ/εF∼1(∼0.3) in the electron (hole) band. Moreover, thermal-conductivity measurements give evidence of a distinct phase line below the upper critical field, where the Zeeman energy becomes comparable to εF and Δ. The observation of this field-induced phase provides insights into previously poorly understood aspects of the highly spin-polarized Fermi liquid in the BCS-BEC cross-over regime. PMID:25378706

  20. Neutron-induced fission cross section of U234 and Np237 measured at the CERN Neutron Time-of-Flight (n_TOF) facility

    NASA Astrophysics Data System (ADS)

    Paradela, C.; Tassan-Got, L.; Audouin, L.; Berthier, B.; Duran, I.; Ferrant, L.; Isaev, S.; Le Naour, C.; Stephan, C.; Tarrío, D.; Trubert, D.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Álvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Badurek, G.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Eleftheriadis, C.; Embid-Segura, M.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; González-Romero, E.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krtička, M.; Lampoudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martínez, T.; Massimi, C.; Mastinu, P.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Tagliente, G.; Tain, J. L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K.

    2010-09-01

    A high-resolution measurement of the neutron-induced fission cross section of U234 and Np237 has been performed at the CERN Neutron Time-of-Flight facility. The cross sections have been determined in a wide energy range from 1 eV to 1 GeV using the evaluated U235 cross section as reference. In these measurements the energy determination for the U234 resonances could be improved, whereas previous discrepancies for the Np237 resonances were confirmed. New cross-section data are provided for high neutron energies that go beyond the limits of prior evaluations, obtaining important differences in the case of Np237.

  1. Prolactin Rescues Immature B-Cells from Apoptosis Induced by B-Cell Receptor Cross-Linking

    PubMed Central

    Flores-Fernández, Rocio; Blanco-Favela, Francisco; Fuentes-Pananá, Ezequiel M.; Chávez-Sánchez, Luis; Gorocica-Rosete, Patricia; Pizaña-Venegas, Alberto; Chávez-Rueda, Adriana Karina

    2016-01-01

    Prolactin has an immunomodulatory effect and has been associated with B-cell-triggered autoimmune diseases, such as systemic lupus erythematosus (SLE). In mice that develop SLE, the PRL receptor is expressed in early bone marrow B-cells, and increased levels of PRL hasten disease manifestations, which are correlated with a reduction in the absolute number of immature B-cells. The aim of this work was to determine the effect of PRL in an in vitro system of B-cell tolerance using WEHI-231 cells and immature B-cells from lupus prone MRL/lpr mice. WEHI-231 cells express the long isoform of the PRL receptor, and PRL rescued the cells from cell death by decreasing the apoptosis induced by the cross-linking of the B-cell antigen receptor (BCR) as measured by Annexin V and active caspase-3. This decrease in apoptosis may have been due to the PRL and receptor interaction, which increased the relative expression of antiapoptotic Bcl-xL and decreased the relative expression of proapoptotic Bad. In immature B-cells from MRL/lpr mice, PRL increased the viability and decreased the apoptosis induced by the cross-linking of BCR, which may favor the maturation of self-reactive B-cells and contribute to the onset of disease. PMID:27314053

  2. Hyperbranched polyethyleneimine induced cross-linking of polyamide-imide nanofiltration hollow fiber membranes for effective removal of ciprofloxacin.

    PubMed

    Sun, Shi Peng; Hatton, T Alan; Chung, Tai-Shung

    2011-05-01

    This study aims to develop a positively charged nanofiltration (NF) hollow fiber membrane for effective removal of ciprofloxacin from water. A novel NF membrane was fabricated by hyperbranched polyethyleneimine (PEI) induced cross-linking on a polyamide-imide hollow fiber support. The spongy-like, fully porous membrane support provides minimal transport resistance and sufficient mechanical strengths for water permeation under high pressures. It is found that the PEI modification significantly influences NF performance through the mechanisms of size exclusion, charge repulsion, and solute-membrane affinity. Specifically, after PEI induced cross-linking, the membrane pore size is significantly reduced. The membrane surface becomes more hydrophilic and positively charged. As a result of these synergic effects, the rejection of ciprofloxacin is substantially enhanced. Furthermore, experimental results show that the molecular weight of PEI has tremendous effect on NF performance of the as-modified membrane. The NF membrane modified by a high molecular weight PEI_60K exhibits the highest rejection, the lowest fouling tendency, and keeps a constant flux over the whole pH range. This study may have great potential for developing high-performance antifouling NF hollow fiber membranes for various industrial applications.

  3. Immunization of rabbits with nematode Ascaris lumbricoides antigens induces antibodies cross-reactive to house dust mite Dermatophagoides farinae antigens.

    PubMed

    Nakazawa, Takuya; Khan, Al Fazal; Yasueda, Hiroshi; Saito, Akemi; Fukutomi, Yuma; Takai, Toshiro; Zaman, Khalequz; Yunus, Md; Takeuchi, Haruko; Iwata, Tsutomu; Akiyama, Kazuo

    2013-01-01

    There are controversial reports on the relationship between helminthic infection and allergic diseases. Although IgE cross-reactivity between nematode Ascaris antigens and house dust-mite allergens in allergic patients have been reported, whether Ascaris or the mite is the primary sensitizer remains unknown. Here we found that immunization of naïve animals with Ascaris lumbricoides (Al) antigens induced production of antibodies cross-reactive to mite antigens from Dermatophagoides farinae (Df). Sera from Bangladeshi children showed IgE reactivity to Ascaris and mite extracts. IgG from rabbits immunized with Al extract exhibited reactivity to Df antigens. Treatment of the anti-Al antibody with Df antigen-coupled beads eliminated the reactivity to Df antigens. In immunoblot analysis, an approximately 100-kDa Df band was the most reactive to anti-Al IgG. The present study is the first step towards the establishment of animal models to study the relationship between Ascaris infection and mite-induced allergic diseases.

  4. Cross-clade neutralizing antibodies against HIV-1 induced in rabbits by focusing the immune response on a neutralizing epitope

    SciTech Connect

    Zolla-Pazner, Susan; Cohen, Sandra; Pinter, Abraham; Krachmarov, Chavdar; Wrin, Terri; Wang Shixia; Lu Shan

    2009-09-15

    Studies were performed to induce cross-clade neutralizing antibodies (Abs) by testing various combinations of prime and boost constructs that focus the immune response on structurally-conserved epitopes in the V3 loop of HIV-1 gp120. Rabbits were immunized with gp120 DNA containing a V3 loop characterized by the GPGR motif at its tip, and/or with gp120 DNA with a V3 loop carrying the GPGQ motif. Priming was followed by boosts with V3-fusion proteins (V3-FPs) carrying the V3 sequence from a subtype B virus (GPGR motif), and/or with V3 sequences from subtypes A and C (GPGQ motif). The broadest and most consistent neutralizing responses were generated when using a clade C gp120 DNA prime and with the V3{sub B}-FP boost. Immune sera displayed neutralizing activity in three assays against pseudoviruses and primary isolates from subtypes A, AG, B, C, and D. Polyclonal Abs in the immune rabbit sera neutralized viruses that were not neutralized by pools of human anti-V3 monoclonal Abs. Greater than 80% of the neutralizing Abs were specific for V3, showing that the immune response could be focused on a neutralizing epitope and that vaccine-induced anti-V3 Abs have cross-clade neutralizing activity.

  5. Theoretical modeling of the Casimir force-induced instability in freestanding nanowires with circular cross-section

    NASA Astrophysics Data System (ADS)

    Farrokhabadi, Amin; Abadian, Naeime; Rach, Randolph; Abadyan, Mohamadreza

    2014-09-01

    The Casimir force can induce instability and adhesion in freestanding nanostructures. Previous research efforts in this area have exclusively focused on modeling the instability in structures with planar or rectangular cross-section, while, to the best knowledge of the authors, no attention has been paid to investigate this phenomenon for nanowires with circular cross-section. In this study, effects of the Casimir force on the instability and adhesion of freestanding Cylinder-Plate and Cylinder-Cylinder geometries are investigated, which are commonly encountered in real nanodevices. To compute the Casimir force, two approaches, i.e. the proximity force approximation (PFA) for small separations and Dirichlet asymptotic approximation (scattering theory) for large separations, are considered. A continuum mechanics theory is employed, in conjunction with the Euler-beam model, to obtain constitutive equations of the systems. The governing nonlinear constitutive equations of the nanostructures are solved using two different approaches, i.e. the analytical modified Adomian decomposition (MAD) and the numerical finite difference method (FDM). The detachment length and minimum gap, both of which prevent the Casimir force-induced adhesion, are computed for both configurations.

  6. Critical features of acute stress-induced cross-sensitization identified through the hypothalamic-pituitary-adrenal axis output

    PubMed Central

    Belda, Xavier; Nadal, Roser; Armario, Antonio

    2016-01-01

    Stress-induced sensitization represents a process whereby prior exposure to severe stressors leaves animals or humans in a hyper-responsive state to further stressors. Indeed, this phenomenon is assumed to be the basis of certain stress-associated pathologies, including post-traumatic stress disorder and psychosis. One biological system particularly prone to sensitization is the hypothalamic-pituitary-adrenal (HPA) axis, the prototypic stress system. It is well established that under certain conditions, prior exposure of animals to acute and chronic (triggering) stressors enhances HPA responses to novel (heterotypic) stressors on subsequent days (e.g. raised plasma ACTH and corticosterone levels). However, such changes remain somewhat controversial and thus, the present study aimed to identify the critical characteristics of the triggering and challenging stressors that affect acute stress-induced HPA cross-sensitization in adult rats. We found that HPA cross-sensitization is markedly influenced by the intensity of the triggering stressor, whereas the length of exposure mainly affects its persistence. Importantly, HPA sensitization is more evident with mild than strong challenging stressors, and it may remain unnoticed if exposure to the challenging stressor is prolonged beyond 15 min. We speculate that heterotypic HPA sensitization might have developed to optimize biologically adaptive responses to further brief stressors. PMID:27511270

  7. Induction and repair of DNA cross-links induced by sulfur mustard in the A-549 cell line followed by a comet assay.

    PubMed

    Jost, Petr; Svobodova, Hana; Stetina, Rudolf

    2015-07-25

    Sulfur mustard is a highly toxic chemical warfare agent with devastating impact on intoxicated tissues. DNA cross-links are probably the most toxic DNA lesions induced in the cell by sulfur mustard. The comet assay is a very sensitive method for measuring DNA damage. In the present study using the A-549 lung cell line, the comet assay protocol was optimized for indirect detection of DNA cross-links induced by sulfur mustard. The method is based on the additional treatment of the assayed cells containing cross-links with the chemical mutagen, styrene oxide. Alkali-labile adducts of styrene oxide cause DNA breaks leading to the formation of comets. A significant dose-dependent reduction of DNA migration of the comet's tail was found after exposing cells to sulfur mustard, indicative of the amount of sulfur mustard induced cross-links. The remarkable decrease of % tail DNA could be observed as early as 5min following exposure to sulfur mustard and the maximal effect was found after 30min, when DNA migration was reduced to the minimum. Sulfur mustard preincubated in culture medium without cells lost its ability to induce cross-links and had a half-life of about 15min. Pre-incubation longer than 30min does not lead to a significant increase in cross-links when applied to cells. However, the amount of cross-links is decreased during further incubation due to repair. The current modification of the comet assay provides a useful tool for detecting DNA cross-links induced by sulfur mustard and could be used for detection of other DNA cross-linking agents such as chemotherapeutic drugs.

  8. Experimental cross-sections for proton-induced nuclear reactions on natMo

    NASA Astrophysics Data System (ADS)

    Červenák, Jaroslav; Lebeda, Ondřej

    2016-08-01

    In the framework of the Co-ordinated Research Project of the IAEA, we measured in detail cross-sections of the nuclear reactions natMo(p,x)93gTc, 93mTc, 93m+gTc, 94gTc, 94mTc, 95gTc, 95mTc, 96m+gTc, 97mTc, 99mTc, 90Mo, 93mMo, 99Mo, 88gNb, 88mNb, 89gNb, 89mNb, 90m+gNb, 90m+gNbcum, 91mNb, 92mNb, 95gNb, 95mNb, 95m+gNb, 96Nb, 97m+gNb, 88m+gZrcum and 89m+gZrcum in the energy range of 6.9-35.8 MeV. The data for formation of 97mTc, 88gNb, 88mNb and 89mNb are reported for the first time. The obtained results were compared to the prediction of the nuclear reaction model code TALYS adopted from the TENDL-2015 library and to the previously published cross-sections. The thick target yields for all the radionuclides were calculated from the measured data. We suggest recommended cross-sections and thick target yields for the 100Mo(p,2n)99mTc, 100Mo(p,x)99Mo and natMo(p,x)96m+gTc nuclear reactions deduced from the selected experimental data.

  9. A Robust Cross-Linking Strategy for Block Copolymer Worms Prepared via Polymerization-Induced Self-Assembly

    PubMed Central

    2016-01-01

    A poly(glycerol monomethacrylate) (PGMA) chain transfer agent is chain-extended by reversible addition–fragmentation chain transfer (RAFT) statistical copolymerization of 2-hydroxypropyl methacrylate (HPMA) with glycidyl methacrylate (GlyMA) in concentrated aqueous solution via polymerization-induced self-assembly (PISA). A series of five free-standing worm gels is prepared by fixing the overall degree of polymerization of the core-forming block at 144 while varying its GlyMA content from 0 to 20 mol %. 1H NMR kinetics indicated that GlyMA is consumed much faster than HPMA, producing a GlyMA-rich sequence close to the PGMA stabilizer block. Temperature-dependent oscillatory rheological studies indicate that increasing the GlyMA content leads to progressively less thermoresponsive worm gels, with no degelation on cooling being observed for worms containing 20 mol % GlyMA. The epoxy groups in the GlyMA residues can be ring-opened using 3-aminopropyltriethoxysilane (APTES) in order to prepare core cross-linked worms via hydrolysis-condensation with the siloxane groups and/or hydroxyl groups on the HPMA residues. Perhaps surprisingly, 1H NMR analysis indicates that the epoxy–amine reaction and the intermolecular cross-linking occur on similar time scales. Cross-linking leads to stiffer worm gels that do not undergo degelation upon cooling. Dynamic light scattering studies and TEM analyses conducted on linear worms exposed to either methanol (a good solvent for both blocks) or anionic surfactant result in immediate worm dissociation. In contrast, cross-linked worms remain intact under such conditions, provided that the worm cores comprise at least 10 mol % GlyMA. PMID:27134311

  10. Induced photoemission from driven nonadiabatic dynamics in an avoided crossing system

    SciTech Connect

    Arasaki, Yasuki; Mizuno, Yuta; Takatsuka, Kazuo; Scheit, Simona

    2014-12-21

    When vibrational dynamics on an ionic state (large dipole moment) is coupled to that on a neutral state (small dipole moment) such as at an avoided crossing in the alkali halide system, the population transfer between the states cause oscillation of the molecular dipole, leading to dipole emission. Such dynamics may be driven by an external field. We study how the coupled wavepacket dynamics is affected by the parameters (intensity, frequency) of the driving field with the aim of making use of the photoemission as an alternative detection scheme of femtosecond and subfemtosecond vibrational and electronic dynamics or as a characteristic optical source.

  11. Measurements of proton-induced production cross sections for Cl-36 from Ca and K

    NASA Technical Reports Server (NTRS)

    Imamura, M.; Shibata, S.; Nishiizumi, K.; Caffee, M. W.

    1998-01-01

    Production cross sections for Cl-36 (half-life= 3.01 x 10(exp 5) y) have been measured for the nat.K(p,x), 39 K(p,x), nat.Ca(p,x) and Ca-40(p,x) reactions up to 40 MeV. The results of nat.Ca(p,x) reaction are generally consistent with measurements performed at somewhat higher energies. With the completion of these measurements it is now possible to proceed with model calculations of the solar cosmic ray (SCR) flux over the last 400 ky based on measurements of lunar surface materials.

  12. Evaluation of cross-sections for particle induced gamma-ray emission (PIGE) spectroscopy

    NASA Astrophysics Data System (ADS)

    Gurbich, A. F.

    2014-07-01

    The extension of the cross-section evaluation procedure to PIGE data was investigated and the first results are reported. Two different cases were studied: the gamma emission accompanying inelastic scattering of protons, and the (p,γ)-reaction. The corresponding theoretical calculations were performed in the framework of R-matrix and DWBA for the (p,p‧γ) reaction on 23Na, and using statistical model for the proton radiative capture by 52Cr. The possibility of achieving a close fit to the experimental data is demonstrated.

  13. The estimated incidence of induced abortion in Kenya: a cross-sectional study.

    PubMed

    Mohamed, Shukri F; Izugbara, Chimaraoke; Moore, Ann M; Mutua, Michael; Kimani-Murage, Elizabeth W; Ziraba, Abdhalah K; Bankole, Akinrinola; Singh, Susheela D; Egesa, Caroline

    2015-08-21

    The recently promulgated 2010 constitution of Kenya permits abortion when the life or health of the woman is in danger. Yet broad uncertainty remains about the interpretation of the law. Unsafe abortion remains a leading cause of maternal morbidity and mortality in Kenya. The current study aimed to determine the incidence of induced abortion in Kenya in 2012. The incidence of induced abortion in Kenya in 2012 was estimated using the Abortion Incidence Complications Methodology (AICM) along with the Prospective Morbidity Survey (PMS). Data were collected through three surveys, (i) Health Facilities Survey (HFS), (ii) Prospective Morbidity Survey (PMS), and (iii) Health Professionals Survey (HPS). A total of 328 facilities participated in the HFS, 326 participated in the PMS, and 124 key informants participated in the HPS. Abortion numbers, rates, ratios and unintended pregnancy rates were calculated for Kenya as a whole and for five geographical regions. In 2012, an estimated 464,000 induced abortions occurred in Kenya. This translates into an abortion rate of 48 per 1,000 women aged 15-49, and an abortion ratio of 30 per 100 live births. About 120,000 women received care for complications of induced abortion in health facilities. About half (49%) of all pregnancies in Kenya were unintended and 41% of unintended pregnancies ended in an abortion. This study provides the first nationally-representative estimates of the incidence of induced abortion in Kenya. An urgent need exists for improving facilities' capacity to provide safe abortion care to the fullest extent of the law. All efforts should be made to address underlying factors to reduce risk of unsafe abortion.

  14. Circuit QED: cross-Kerr effect induced by a superconducting qutrit without classical pulses

    NASA Astrophysics Data System (ADS)

    Liu, Tong; Zhang, Yang; Guo, Bao-Qing; Yu, Chang-Shui; Zhang, Wei-Ning

    2017-09-01

    The realization of cross-Kerr nonlinearity is an important task for many applications in quantum information processing. In this work, we propose a method for realizing cross-Kerr nonlinearity interaction between two superconducting coplanar waveguide resonators coupled by a three-level superconducting flux qutrit (coupler). Because the resonator photons are virtually excited and the coupler is unexcited for the entire process, the effect of resonator decay and the coupler decoherence are greatly minimized. More importantly, compared with the previous proposals, our proposal does not require classical pulses. Furthermore, due to use of only a three-level qutrit, the experimental setup is much simplified when compared with previous proposals requiring a four-level artificial atomic systems. In addition, we implement a two-resonator qubits controlled-phase gate and generate a two-resonator entangled coherent state. Numerical simulation shows that the high-fidelity implementation of the phase gate and creation of the entangled coherent state are feasible with current circuit QED technology.

  15. Investigation of activation cross-section data of proton induced nuclear reactions on rhenium.

    PubMed

    Ditrói, F; Tárkányi, F; Takács, S; Hermanne, A; Yamazaki, H; Baba, M; Mohammadi, A; Ignatyuk, A V

    2013-07-01

    In the frame of systematic investigations of activation cross-section data for different applications the excitation functions of (nat)Re(p,x)(185)Os, (183m)Os, (183g)Os, (182)Os, (181m)Os, (186g)Re, (184m)Re, (184g)Re, (183)Re, (182m)Re, (182g)Re and (181g)Re reactions were measured up to 70MeV. The data for the (nat)Re(p,x) (183m)Os, (183g)Os, (182)Os, (181g)Os,(186g)Re, (184m)Re,(182m)Re, (182g)Re, and (181)Re reactions are reported for the first time. The activation method, the stacked foil irradiation technique and γ-spectroscopy for activity detection were used. The experimental data were compared with predictions of three theoretical codes. From the measured cross-section thick target integral yields were also calculated and presented. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Cross-compartment proteostasis regulation during redox imbalance induced ER stress.

    PubMed

    Maity, Shuvadeep; Basak, Trayambak; Bhat, Ajay; Bhasin, Namrata; Ghosh, Asmita; Chakraborty, Kausik; Sengupta, Shantanu

    2014-08-01

    Imbalance in protein homeostasis in specific subcellular organelles is alleviated through organelle-specific stress response pathways. As a canonical example of stress activated pathway, accumulation of misfolded proteins in ER activates unfolded protein response (UPR) in almost all eukaryotic organisms. However, very little is known about the involvement of proteins of other organelles that help to maintain the cellular protein homeostasis during ER stress. In this study, using iTRAQ-based LC-MS approach, we identified organelle enriched proteins that are differentially expressed in yeast (Saccharomyces cerevisiae) during ER stress in the absence of UPR sensor Ire1p. We have identified about 750 proteins from enriched organelle fraction in three independent iTRAQ experiments. Induction of ER stress resulted in the differential expression of 93 proteins in WT strains, 40 of which were found to be dependent on IRE1. Our study reveals a cross-talk between ER- and mitochondrial proteostasis exemplified by an Ire1p-dependent induction of Hsp60p, a mitochondrial chaperone. Thus, in this study, we show changes in protein levels in various organelles in response to ER stress. A large fraction of these changes were dependent on canonical UPR signalling through Ire1, highlighting the importance of interorganellar cross-talk during stress. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Measurement of alpha-induced reaction cross sections on erbium isotopes for γ process studies

    NASA Astrophysics Data System (ADS)

    Kiss, G. G.; Szücs, T.; Török, Zs.; Fülöp, Zs.; Gyürky, Gy.; Halász, Z.; Somorjai, E.; Rauscher, T.

    2014-05-01

    The cross sections of the 162Er(α,γ)166Yb and 162,164,166Er(α,n)165,167,169Yb reactions have been measured at MTA Atomki. The radiative alpha capture reaction cross section was measured between Ec.m. = 11.21 MeV and Ec.m. = 16.09 MeV just above the astrophysically relevant energy region (which lies between 7.8 and 11.48 MeV at T9 = 3 GK). The 162Er(α,n)165Yb, 164Er(α,n)167Yb and 166Er(α,n)169Yb reactions were studied between Ec.m. = 12.19 and 16.09 MeV, Ec.m. = 13.17 and 16.59 MeV and Ec.m. = 12.68 and 17.08 MeV, respectively. The aim of this work is to provide experimental data for modeling the γ process which is thought to be responsible for the production of the proton-rich isotopes heavier than iron.

  18. Seeing induced cross-talks in filter-based velocity measurements

    NASA Astrophysics Data System (ADS)

    Sreejith, P.; Sridharan, R.; Sankarasubramanian, K.

    Narrow band imaging using Universal Birefringent Filter (UBF) can be used to measure velocity features on the Sun. Velocity maps, in filter-based observations, are created by taking the intensity differences between the blue and red wing images of a chosen spectral line. In the case of variable seeing, there is a large probability that one of the (red- or blue-) wing images can be affected more compared to the other. Such differential seeing leads to spurious velocity values which are contributed due to cross-talk from the intensity, and found to be more pronounced in umbra and penumbra of sunspots. Simulations are carried out to estimate and understand the sources of the cross-talk. Variable seeing conditions are created using the Adaptive Optics Performance Evaluator (AOPE) software. The point-spread-function (PSF) produced by the AOPE is used to generate the red- and blue-wing images. In this paper, we also discuss the advantages of using AO corrected images in such variable seeing scenario.

  19. Starvation-induced cross protection against heat or H2O2 challenge in Escherichia coli.

    PubMed

    Jenkins, D E; Schultz, J E; Matin, A

    1988-09-01

    Glucose- or nitrogen-starved cultures of Escherichia coli exhibited enhanced resistance to heat (57 degrees C) or H2O2 (15 mM) challenge, compared with their exponentially growing counterparts. The degree of resistance increased with the time for which the cells were starved prior to the challenge, with 4 h of starvation providing the maximal protection. Protein synthesis during starvation was essential for these cross protections, since chloramphenicol addition at the onset of starvation prevented the development of thermal or oxidative resistance. Starved cultures also demonstrated stronger thermal and oxidative resistance than did growing cultures adapted to heat, H2O2, or ethanol prior to the heat or H2O2 challenge. Two-dimensional gel electrophoresis of 35S-pulse-labeled proteins showed that subsets of the 30 glucose starvation proteins were also synthesized during heat or H2O2 adaptation; three proteins were common to all three stresses. Most of the common proteins were among the previously identified Pex proteins (J.E. Schultz, G. I. Latter, and A. Matin, J. Bacteriol. 170:3903-3909, 1988), which are independent of cyclic AMP positive control for their induction during starvation. Induction of starvation proteins dependent on cyclic AMP was not important in these cross protections, since a delta cya strain of E. coli K-12 exhibited the same degree of resistance to heat or H2O2 as the wild-type parent did during both growth and starvation.

  20. Measurement of alpha-induced reaction cross sections on erbium isotopes for γ process studies

    SciTech Connect

    Kiss, G. G.; Szücs, T.; Török, Zs.; Fülöp, Zs.; Gyürky, Gy.; Halász, Z.; Somorjai, E.; Rauscher, T.

    2014-05-02

    The cross sections of the {sup 162}Er(α,γ){sup 166}Yb and {sup 162,164,166}Er(α,n){sup 165,167,169}Yb reactions have been measured at MTA Atomki. The radiative alpha capture reaction cross section was measured between E{sub c.m.} = 11.21 MeV and E{sub c.m.} = 16.09 MeV just above the astrophysically relevant energy region (which lies between 7.8 and 11.48 MeV at T{sub 9} = 3 GK). The {sup 162}Er(α,n){sup 165}Yb, {sup 164}Er(α,n){sup 167}Yb and {sup 166}Er(α,n){sup 169}Yb reactions were studied between E{sub c.m.} = 12.19 and 16.09 MeV, E{sub c.m.} = 13.17 and 16.59 MeV and E{sub c.m.} = 12.68 and 17.08 MeV, respectively. The aim of this work is to provide experimental data for modeling the γ process which is thought to be responsible for the production of the proton-rich isotopes heavier than iron.

  1. Characterization and ion-induced degradation of cross-linked poly(methyl methacrylate) studied using time of flight secondary ion mass spectrometry

    NASA Astrophysics Data System (ADS)

    Wagner, M. S.; Lenghaus, K.; Gillen, G.; Tarlov, M. J.

    2006-12-01

    In this study, a series of random copolymers of methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDMA) were prepared as surface-initiated polymer (SIP) films on silicon substrates using atom transfer radical polymerization. Positive and negative ion static time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to characterize SIP films with different MMA/EGDMA monomer ratios in an attempt to quantify their surface composition. However, matrix effects in the positive and negative ion modes led to preferential secondary ion generation from the EGDMA monomer and suppression of secondary ions characteristic of the MMA monomer, precluding accurate quantification using standard linear quantification methods. Ion-induced degradation of these films under 5 keV SF 5+ bombardment was also examined to determine the effect of cross-linking on the accumulation of ion-induced damage. Increasing incorporation of the EGDMA cross-linker in the SIP films decreased the sputter rate and increased the rate of damage accumulation under extended (>10 14 ions/cm 2) 5 keV SF 5+ bombardment. Comparison of the ion bombardment data with thermal degradation of cross-linked PMMA suggests that the presence of the cross-linker impedes degradation by depolymerization, resulting in ion-induced damage accumulation. The increased rate of ion-induced damage accumulation with increased cross-link density also suggests that polymers that can form cross-links during ion bombardment are less amenable to depth profiling using polyatomic primary ions.

  2. Single- and multiple-clade influenza A H5N1 vaccines induce cross protection in ferrets

    PubMed Central

    Forrest, Heather L.; Khalenkov, Alexey M.; Govorkova, Elena A.; Kim, Jeong-Ki; Giudice, Giuseppe Del; Webster, Robert G.

    2009-01-01

    The rapid evolution, genetic diversity, broad host range, and increasing human infection with avian influenza A (H5N1) viruses highlight the need for an efficacious cross-clade vaccine. Using the ferret model, we compared induction of cross-reactive immunity and protective efficacy of three single-clade H5N1 vaccines and a novel multiple-clade H5N1 vaccine, with and without MF59 adjuvant. Reverse genetics (rg) was used to generate vaccine viruses containing the hemagglutinin (HA) and neuraminidase genes of wild-type H5N1 viruses. Ferrets received 2 doses of inactivated whole-virus vaccine separated by 3 weeks. Single-clade vaccines (7.5 μg HA per dose) included rg-A/Vietnam/1203/04 (clade 1), rg-A/Hong Kong/213/03 (clade 1), and rg-A/Japanese white eye/Hong Kong/1038/06 (clade 2.3). The multiple-clade vaccine contained 3.75 μg HA per dose of each single-clade vaccine and of rg-A/Whooper Swan/Mongolia/244/05 (clade 2.2). Two doses of vaccine were required to substantially increase anti-HA and virus neutralizing antibody titers to H5N1 viruses. MF59 adjuvant enhanced induction of clade-specific and cross-clade serum antibody responses, reduced frequency of infection (as determined by upper respiratory tract virus shedding and seroconversion data), and eliminated disease signs. The rg-A/Hong Kong/213/03 vaccine induced the highest antibody titers to homologous and heterologous H5N1 viruses, while rg-A/Japanese white eye/Hong Kong/1038/06 vaccine induced the lowest. The multiple-clade vaccine was broadly immunogenic against clade 1 and 2 viruses. The rg-A/Vietnam/1203/04 vaccine (the currently stockpiled H5N1 vaccine) most effectively reduced upper respiratory tract virus shedding after challenge with clade 1 and 2 viruses. Importantly, all vaccines protected against lethal challenge with A/Vietnam/1203/04 virus and provided cross-clade protection. PMID:19406182

  3. Spectral Talbot phenomena of frequency combs induced by cross-phase modulation in optical fibers.

    PubMed

    Azaña, José

    2005-02-01

    Cross-phase modulation (XPM) of a frequency comb (finite-duration optical pulse sequence) by an intense, long Gaussian pump pulse is theoretically investigated, and new effects, namely, frequency-domain self-imaging phenomena (integer and fractional Talbot effects), are reported. The conditions favorable for observing spectral self-imaging phenomena by XPM are derived and numerically confirmed. The effects of nonidealities in a practical experiment (e.g., group-delay walk-off and dispersion) are also evaluated. One can use spectral self-imaging to tune the free spectral range of a frequency comb (without affecting the shape and bandwidth of the individual passbands) simply by adjusting the pump power in a fiber XPM scheme.

  4. Electron-Impact-Induced Emission Cross Sections of Neon in the Extreme Ultraviolet

    NASA Technical Reports Server (NTRS)

    Kanik, I.; Ajello, J. M.; James, G. K.

    1996-01-01

    We have measured the extreme ultraviolet (EUV) spectrum of neon produced by electron excitation. The measurements were obtained under optically thin conditions, and at a spectral resolution of 0.5 nm full width at half maximum (FWHM). The most prominent features of the EUV spectrum between 45-80 nm are the resonance lines of Ne I at 73.6 and 74.4 nm and a multiplet of Ne II at 46.14 nm (the average value for the line center of the two closely spaced ion lines at 46.07 and 46.22 nm). Absolute emission cross sections of these lines at 300 eV were measured and compared to other previous measurements.

  5. 4He-induced L X-ray production cross sections in Pt and Bi

    NASA Astrophysics Data System (ADS)

    Ouziane, S.; Amokrane, A.; Toumert, I.; Nourreddine, A.

    2009-05-01

    L shell X-ray production cross sections for 4He on Pt and Bi are measured at 2.0, 2.3 and 3.0 MeV. Good agreement is found with the available data of Balsamo et al. [A. Balsamo, N. De Cesare, F. Murolo, E. Perillo, G. Spadaccini, M. Vigilante, J. Phys. B: Atom. Mol. Opt. Phys. 32 (1999) 5699]. The results are compared with those of theoretical calculations using the ECPSSR model [W. Brandt, G. Lapicki, Phys. Rev. A 23 (1981) 1717]. The difference already observed at low incident ion energy between ECPSSR calculations and measured data for the L β and L γ lines clearly appears in this work.

  6. Electron-Impact-Induced Emission Cross Sections of Neon in the Extreme Ultraviolet

    NASA Technical Reports Server (NTRS)

    Kanik, I.; Ajello, J. M.; James, G. K.

    1996-01-01

    We have measured the extreme ultraviolet (EUV) spectrum of neon produced by electron excitation. The measurements were obtained under optically thin conditions, and at a spectral resolution of 0.5 nm full width at half maximum (FWHM). The most prominent features of the EUV spectrum between 45-80 nm are the resonance lines of Ne I at 73.6 and 74.4 nm and a multiplet of Ne II at 46.14 nm (the average value for the line center of the two closely spaced ion lines at 46.07 and 46.22 nm). Absolute emission cross sections of these lines at 300 eV were measured and compared to other previous measurements.

  7. Activation cross sections for reactions induced by 14 MeV neutrons on natural tantalum

    SciTech Connect

    Luo Junhua; Tuo Fei; Kong Xiangzhong

    2009-05-15

    Cross sections for (n,2n), (n,p), (n,n{sup '}{alpha}), (n,t), (n,d{sup '}), and (n,{alpha}) reactions have been measured on tantalum isotopes at the neutron energies of 13.5 to 14.7 MeV using the activation technique. Data are reported for the following reactions: {sup 181}Ta(n,2n){sup 180}Ta{sup g}, {sup 181}Ta(n,p){sup 181}Hf, {sup 181}Ta(n,n{sup '}{alpha}){sup 177}Lu{sup m}, {sup 181}Ta(n,t){sup 179}Hf{sup m2}, {sup 181}Ta(n,d{sup '}){sup 180}Hf{sup m}, and {sup 181}Ta(n,{alpha}){sup 178}Lu{sup m}. The neutron fluences were determined using the monitor reaction {sup 27}Al(n,{alpha}){sup 24}Na. Results were discussed and compared with the previous works.

  8. Cross section calculations of medical 103Pd radioisotope using α and 3He induced reactions

    NASA Astrophysics Data System (ADS)

    Demir, Bayram; Sarpün, Ismail Hakkı; Dogan, Yunus Emre

    2016-11-01

    One of the most popular radioisotopes used in the prostate brachytherapy is Palladium-103 (103Pd). The radioactive plaque is sewn onto the eye as to cover the intraocular tumor shadow with a 2-3 mm margin. These plaques are temporary and radiation is continuously delivered over 5 to 7 days. At the end of treatment, the plaque is removed from eye. In this study, production cross-section calculations of 103Pd radionuclide used in brachytherapy produced by 101Ru(α,2n), 100Ru(α,n), 102Ru(3He,2n) and 101Ru(3He,n) reactions have been investigated in the different incident energy range up to 35 MeV. Twocomponent Exciton model and Generalized Superfluid model of the TALYS 1.6 code used to perform calculations and calculation results were compared with experimental results reported in the literature.

  9. High frequency of cross-reactive cytotoxic T lymphocytes elicited during the virus-induced polyclonal cytotoxic T lymphocyte response

    PubMed Central

    1993-01-01

    Polyclonal stimulation of CD8+ cytotoxic T lymphocytes (CTL) occurs during infection with many viruses including those not known to transform CTL or encode superantigens. This polyclonal CTL response includes the generation of high levels of allospecific CTL directed against many class I haplotypes. In this report we investigated whether the allospecific CTL generated during an acute lymphocytic choriomeningitis virus (LCMV) infection of C57BL/6 mice were stimulated specifically by antigen recognition or nonspecifically by polyclonal mechanisms possibly involving lymphokines or superantigens. An examination of the ability of different strains of mice to induce high levels of CTL specific for a given alloantigen showed that most, but not all, strains generated high levels of allospecific CTL, and that their abilities to generate them mapped genetically to the major histocompatibility complex locus, exclusive of the class II region. This indicated that the virus-induced allospecific CTL generation was independent of the class II allotype, and mice depleted of CD4+ cells generated allospecific CTL, indicating independence of class II-CD4+ cell interactions and resulting CD4+ cell-secreted lymphokines. FACS staining with a variety of V beta-binding antibodies did not show a superantigen-like depletion or enrichment of any tested V beta + subset during infection. Several experiments provided evidence in support of direct stimulation of CD8+ cells via the T cell receptor: (a) both virus- and allo-specific killing were enriched within a given V beta subpopulation; (b) relative CTL precursor frequencies against different class I alloantigens changed during the course of virus infection; (c) the relative levels of virus-induced, allospecific CTL-mediated lysis at day 8 after infection did not parallel the CTL precursor frequencies before infection; and (d) limiting dilution analyses of day 8 LCMV- infected spleen cells stimulated by virus-infected syngeneic peritoneal

  10. Identification of cross-linked peptides after click-based enrichment using sequential collision-induced dissociation and electron transfer dissociation tandem mass spectrometry.

    PubMed

    Chowdhury, Saiful M; Du, Xiuxia; Tolić, Nikola; Wu, Si; Moore, Ronald J; Mayer, M Uljana; Smith, Richard D; Adkins, Joshua N

    2009-07-01

    Chemical cross-linking combined with mass spectrometry can be a powerful approach for the identification of protein-protein interactions and for providing constraints on protein structures. However, enrichment of cross-linked peptides is crucial to reduce sample complexity before mass spectrometric analysis. In addition compact cross-linkers are often preferred to provide short spacer lengths, surface accessibility to the protein complexes, and must have reasonable solubility under conditions where the native complex structure is stable. In this study, we present a novel compact cross-linker that contains two distinct features: (1) an alkyne tag and (2) a small molecule detection tag (NO(2)) to maintain reasonable solubility in water. The alkyne tag enables enrichment of the cross-linked peptides after proteolytic cleavage and coupling of an affinity tag using alkyne-azido click chemistry. Neutral loss of the small NO(2) moiety provides a secondary means of detecting cross-linked peptides in MS/MS analyses, providing additional confidence in peptide identifications. We show the labeling efficiency of this cross-linker, which we termed CLIP (click-enabled linker for interacting proteins) using ubiquitin. The enrichment capability of CLIP is demonstrated for cross-linked ubiquitin in highly complex E. coli cell lysates. Sequential collision-induced dissociation tandem mass spectrometry (CID-MS/MS) and electron transfer dissociation (ETD)-MS/MS of intercross-linked peptides (two peptides connected with a cross-linker) are also demonstrated for improved automated identification of cross-linked peptides.

  11. Tables of Neutron-Induced Fission Cross Section for Various Pu, U, and Th Isotopes, Deduced from Measured Fission Probabilites

    SciTech Connect

    Younes, W; Britt, H C

    2003-03-31

    Cross sections for neutron-induced fission of {sup 231,233}Th, {sup 234,235,236,237,239}U, and {sup 240,241,243}Pu are presented in tabular form for incident neutron energies of 0.1 {le} E{sub n}(MeV) {le} 2.5. The cross sections were obtained by converting measured fission probabilities from (t,pf) reactions on mass-A targets to (n,f) cross sections on mass-A + 1 neutron targets, by using modeling to compensate for the differences in the reaction mechanisms. Data from Britt et al. were used for the {sup 234}U(t,pf) reaction, from Cramer et al. for the {sup 230,232}Th(t,pf), {sup 236,238}U(t,pf), and {sup 240,242}Pu(t,pf) reactions, and from Britt et al. for the {sup 233,235}U(t,pf) and {sup 239}Pu(t,pf) reactions. The fission probabilities P{sub (t,pf)}(E{sub x}), measured as a function of excitation energy E{sub x} of the compound system formed by the (t,p) reaction, are listed in the tables with the corresponding deduced cross sections as a function of incident neutron energy E{sub n}, {sigma}{sub (n,f)}(E{sub n}). The excitation energy and incident neutron energy are related by E{sub x} = E{sub n} + B{sub n}, where B{sub n}, where B{sub n} is the neutron binding energy. Comparison with ENDF/B-VI evaluations of the well-measured {sup 234,235,236}U(n,f) and {sup 240,241}Pu(n,f) cross sections confirms the accuracy of the present results within a 10% standard deviation above E{sub n} = 1 MeV. Below E{sub n} = 1 MeV, localized deviations of at most {+-} 20% are observed.

  12. Research frontiers in drought-induced tree mortality: Crossing scales and disciplines

    DOE PAGES

    Hartmann, Henrik; Adams, Henry D.; Anderegg, William R. L.; ...

    2015-01-12

    Sudden and widespread forest die-back and die-off (e.g., Huang & Anderegg, 2012) and increased mortality rates (e.g., Peng et al., 2011) in many forest ecosystems across the globe have been linked to drought and elevated temperatures (Allen et al., 2010, Fig. 1). Furthermore, these observations have caused a focus on the physiological mechanisms of drought-induced tree mortality (e.g. McDowell et al., 2008) and many studies, both observational and manipulative, have been carried out to explain tree death during drought from a physiological perspective.

  13. Cross-Resistance and Resistance Longevity as Induced by Bean Leaf Beetle, Cerotoma trifurcata and Soybean Looper, Pseudoplusia includens herbivory on Soybean

    PubMed Central

    Srinivas, P.; Danielson, Stephen D.; Smith, C. Michael; Foster, John E.

    2001-01-01

    Cross-resistance, and longevity of resistance, induced by the bean leaf beetle, Cerotoma trifurcata, was studied IN the soybean PI 227687 that exhibited induced response in earlier studies. Bean leaf beetle adults and soybean looper, Pseudoplusia includens, larvae were used to induce resistance and to determine beetle feeding preference. Beetles were collected from soybean fields 2 to 5 days prior to the feeding preference test. The level of cross-resistance induced by soybean looper herbivory to subsequent bean leaf beetle feeding was higher when compared to cross-resistance induced by bean leaf beetle herbivory against subsequent feeding by soybean looper. Further, herbivory by the bean leaf beetle also induced resistance against soybean looper feeding. In the longevity study, leaflets from treated plants were collected 5, 10, 12, 14, 16, 20 and 25 days after initiation of feeding. Pairwise comparisons of leaflets from plants treated by bean leaf beetle herbivory with untreated plants revealed that induced responses were highest 14 and lowest 25 days after initiation of feeding. On other sampling days, levels of induced response varied with the sampling day. PMID:15455065

  14. Cross-resistance and resistance longevity as induced by bean leaf beetle, Cerotoma trifurcata and soybean looper, Pseudoplusia includens herbivory on soybean.

    PubMed

    Srinivas, P; Danielson, S D; Smith, C M; Foster, J E

    2001-01-01

    Cross-resistance, and longevity of resistance, induced by the bean leaf beetle, Cerotoma trifurcata, was studied IN the soybean PI 227687 that exhibited induced response in earlier studies. Bean leaf beetle adults and soybean looper, Pseudoplusia includens, larvae were used to induce resistance and to determine beetle feeding preference. Beetles were collected from soybean fields 2 to 5 days prior to the feeding preference test. The level of cross-resistance induced by soybean looper herbivory to subsequent bean leaf beetle feeding was higher when compared to cross-resistance induced by bean leaf beetle herbivory against subsequent feeding by soybean looper. Further, herbivory by the bean leaf beetle also induced resistance against soybean looper feeding. In the longevity study, leaflets from treated plants were collected 5, 10, 12, 14, 16, 20 and 25 days after initiation of feeding. Pairwise comparisons of leaflets from plants treated by bean leaf beetle herbivory with untreated plants revealed that induced responses were highest 14 and lowest 25 days after initiation of feeding. On other sampling days, levels of induced response varied with the sampling day.

  15. The effect of flat bar supports on the cross flow induced response of heat exchanger U-tubes

    SciTech Connect

    Weaver, D.S.; Schneider, W.

    1982-01-01

    A wind tunnel study was conducted to determine the effect of flat bar supports on the cross-flow induced response of heat exchanger U-tubes. The 13 mm diameter tubes formed a triangular array with a pitch ratio o 1.57 and a mean U-bend diameter of about 1.5 m. A 0.3 m long section of the array was exposed to a flow parallel to the plane of the U-bends. Experiments were conducted with no supports, with 1 set of flat bars at the apex and with 2 sets of flat bar supports at the apex and 45/sup 0/ points. In each case, the tube response was monitored to a flow velocity beyond that required for fluid elastic instability. Limited experiments were also conducted to examine the effect of tube support clearance on tube response. Conclusions are drawn regarding the effectiveness of flat bars as U-bend antivibration supports.

  16. Activation cross-sections of proton induced reactions on vanadium in the 37-65 MeV energy range

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.

    2016-08-01

    Experimental excitation functions for proton induced reactions on natural vanadium in the 37-65 MeV energy range were measured with the activation method using a stacked foil irradiation technique. By using high resolution gamma spectrometry cross-section data for the production of 51,48Cr, 48V, 48,47,46,44m,44g,43Sc and 43,42K were determined. Comparisons with the earlier published data are presented and results predicted by different theoretical codes (EMPIRE and TALYS) are included. Thick target yields were calculated from a fit to our experimental excitation curves and compared with the earlier experimental yield data. Depth distribution curves to be used for thin layer activation (TLA) are also presented.

  17. Experimental cross-sections for proton induced nuclear reactions on mercury up to 65 MeV

    NASA Astrophysics Data System (ADS)

    Hermanne, A.; Tárkányi, F.; Takács, S.; Ditrói, F.; Szücs, Z.; Brezovcsik, K.

    2016-07-01

    Cross-sections for formation of activation products induced by protons on natural mercury targets were measured. Results for 196m,196g,197g(cum), 198m,198g,199g(cum), 200g(cum), 201,202Tl, 194g(cum), 195g(cum), 196g(cum), 198m,199g(cum) Au and 195m,197m,203Hg are presented up to 65 MeV incident particle energy, many of these for the first time. The experimental data are compared with literature values and with the predictions of the TALYS 1.6 code (results taken from TENDL-2015 on-line library), thick target yields were derived and possible applications in biomedical sciences are discussed.

  18. Modulation instability induced by cross-phase modulation in negative index materials with higher-order nonlinearity

    NASA Astrophysics Data System (ADS)

    Liu, Ying; Xue, Yan Ling; Yu, Chuanxi

    2015-03-01

    Based on the dispersive Drude model in negative index materials (NIMs), nonlinear coupled Schodinger equations are derived for two copropagating optical waves with cubic-quintic nonlinearity and modulation instabilities induced by cross-phase modulation (XMI) are studied by using standard linear stability analysis and the Drude electromagnetic model. It is shown that the quintic nonlinearity strengthens the XMI with broader XMI spectra and higher peak gain. It is found that the XMI gain is obviously larger in the region with anomalous group velocity dispersion (GVD) than that in the region with normal GVD. It is also shown that the serious XMI occurs when two optical waves propagate simultaneously in the positive refractive index region or in different refractive index regions. The work provides a theoretical basis for the extinction or utilization of XMI in the propagation of high power and high speed signals in NIMs.

  19. Zero to π Continuously Controllable Cross Phase Modulation in Doppler Broadened N-Type Electromagnetically Induced Transparency Medium.

    PubMed

    Li, R B; Zhu, C J; Deng, L; Hagley, E W

    2015-10-01

    We demonstrate an observation of zero to π continuously controllable cross-phase-modulation based on N-type electromagnetically induced transparency scheme in a room-temperature (87)Rb vapor. We theoretically and experimentally show that the signal field acquires a π phase shift compared with the reference light in the presence of the phase-control field. Using the method of the optical Mach-Zehnder interferometer, we demonstrate that a zero to π continuously controllable phase gate can be built by modulating the phase-control field. In addition, our theoretical calculation agrees well with the experimental observation, and the results presented in this work hold the potential applications for the orthogonal polarization/vector gate in the quantum information processing.

  20. Zero to π Continuously Controllable Cross Phase Modulation in Doppler Broadened N-Type Electromagnetically Induced Transparency Medium

    PubMed Central

    Li, R. B.; Zhu, C. J.; Deng, L.; Hagley, E. W.

    2016-01-01

    We demonstrate an observation of zero to π continuously controllable cross-phase-modulation based on N-type electromagnetically induced transparency scheme in a room-temperature 87Rb vapor. We theoretically and experimentally show that the signal field acquires a π phase shift compared with the reference light in the presence of the phase-control field. Using the method of the optical Mach-Zehnder interferometer, we demonstrate that a zero to π continuously controllable phase gate can be built by modulating the phase-control field. In addition, our theoretical calculation agrees well with the experimental observation, and the results presented in this work hold the potential applications for the orthogonal polarization/vector gate in the quantum information processing. PMID:27453675

  1. Activation cross-sections of deuteron induced nuclear reactions on neodymium up to 50 MeV

    NASA Astrophysics Data System (ADS)

    Tárkányi, F.; Takács, S.; Ditrói, F.; Hermanne, A.; Yamazaki, H.; Baba, M.; Mohammadi, A.; Ignatyuk, A. V.

    2014-04-01

    In the frame of a systematic study of activation cross sections of deuteron induced nuclear reactions on rare earths, the reactions on neodymium for production of therapeutic radionuclides were measured for the first time. The excitation functions of the natNd(d,x) 151,150,149,148m,148g,146,144,143Pm, 149,147,139mNd, 142Pr and 139gCe nuclear reactions were assessed by using the stacked foil activation technique and high resolution γ-spectrometry. The experimental excitation functions were compared to the theoretical predictions calculated with the modified model codes ALICE-IPPE-D and EMPIRE-II-D and with the data in the TENDL-2012 library based on latest version of the TALYS code. The application of the data in the field of medical isotope production and nuclear reaction theory is discussed.

  2. Activity and Cross-Reactivity of Antibodies Induced in Mice by Immunization with a Group B Meningococcal Conjugate

    PubMed Central

    Coquillat, D.; Bruge, J.; Danve, B.; Latour, M.; Hurpin, C.; Schulz, D.; Durbec, P.; Rougon, G.

    2001-01-01

    The capsular polysaccharide of group B Neisseria meningitidis is composed of a linear homopolymer of α(2-8) N-acetyl neuraminic acid or polysialic acid (PSA) that is also carried by isoforms of the mammalian neural cell adhesion molecule (NCAM), which is especially expressed on brain cells during development. Here we analyzed the ability of antibodies induced by the candidate vaccine N-propionyl polysaccharide tetanus toxoid conjugate to recognize PSA-NCAM. We hyperimmunized mice to produce a pool of antisera and a series of immunoglobulin G monoclonal antibodies and evaluated their self-reactivity profile by using a battery of tests (immunoprecipitation, immunoblotting, and immunofluorescence detection on live cells and human tissue sections) chosen for their sensitivity and specificity to detect PSA-NCAM in various environments. We also searched for the effects of the vaccine-induced antibodies in two functional assays involving cell lysis or cell migration. Although they were highly bactericidal, all the antibodies tested showed very low or no recognition of PSA-NCAM, in contrast to PSA-specific monoclonal antibodies used as controls. Different patterns of cross-reactions were revealed by the tests used, likely due to affinity and specificity differences among the populations of induced antibodies. Furthermore, neither cell lysis nor perturbation of migration was observed in the presence of the tested antibodies. Importantly, we showed that whereas enzymatic removal of PSA groups from the surfaces of live cells perturbed their migration, blocking them with PSA-specific antibodies was not functionally detrimental. Taken together, our data indicated that this candidate vaccine induced antibodies that could not demonstrate an immunopathologic effect. PMID:11598089

  3. Activity and cross-reactivity of antibodies induced in mice by immunization with a group B meningococcal conjugate.

    PubMed

    Coquillat, D; Bruge, J; Danve, B; Latour, M; Hurpin, C; Schulz, D; Durbec, P; Rougon, G

    2001-11-01

    The capsular polysaccharide of group B Neisseria meningitidis is composed of a linear homopolymer of alpha(2-8) N-acetyl neuraminic acid or polysialic acid (PSA) that is also carried by isoforms of the mammalian neural cell adhesion molecule (NCAM), which is especially expressed on brain cells during development. Here we analyzed the ability of antibodies induced by the candidate vaccine N-propionyl polysaccharide tetanus toxoid conjugate to recognize PSA-NCAM. We hyperimmunized mice to produce a pool of antisera and a series of immunoglobulin G monoclonal antibodies and evaluated their self-reactivity profile by using a battery of tests (immunoprecipitation, immunoblotting, and immunofluorescence detection on live cells and human tissue sections) chosen for their sensitivity and specificity to detect PSA-NCAM in various environments. We also searched for the effects of the vaccine-induced antibodies in two functional assays involving cell lysis or cell migration. Although they were highly bactericidal, all the antibodies tested showed very low or no recognition of PSA-NCAM, in contrast to PSA-specific monoclonal antibodies used as controls. Different patterns of cross-reactions were revealed by the tests used, likely due to affinity and specificity differences among the populations of induced antibodies. Furthermore, neither cell lysis nor perturbation of migration was observed in the presence of the tested antibodies. Importantly, we showed that whereas enzymatic removal of PSA groups from the surfaces of live cells perturbed their migration, blocking them with PSA-specific antibodies was not functionally detrimental. Taken together, our data indicated that this candidate vaccine induced antibodies that could not demonstrate an immunopathologic effect.

  4. Role of p53–fibrinolytic system cross-talk in the regulation of quartz-induced lung injury

    SciTech Connect

    Bhandary, Yashodhar P.; Shetty, Shwetha K.; Marudamuthu, Amarnath S.; Fu, Jian; Pinson, Barbara M.; Levin, Jeffrey; Shetty, Sreerama

    2015-03-01

    Silica is the major component of airborne dust generated by wind, manufacturing and/or demolition. Chronic occupational inhalation of silica dust containing crystalline quartz is by far the predominant form of silicosis in humans. Silicosis is a progressive lung disease that typically arises after a very long latency and is a major occupational concern with no known effective treatment. The mechanism of silicosis is not clearly understood. However, silicosis is associated with increased cell death, expression of redox enzymes and pro-fibrotic cytokines and chemokines. Since alveolar epithelial cell (AEC) death and disruption of alveolar fibrinolysis is often associated with both acute and chronic lung injuries, we explored whether p53-mediated changes in the urokinase-type plasminogen activator (uPA) system contributes to silica-induced lung injury. We further sought to determine whether caveolin-1 scaffolding domain peptide (CSP), which inhibits p53 expression, mitigates lung injury associated with exposure to silica. Lung tissues and AECs isolated from wild-type (WT) mice exposed to silica exhibit increased apoptosis, p53 and PAI-1, and suppression of uPA expression. Treatment of WT mice with CSP inhibits PAI-1, restores uPA expression and prevents AEC apoptosis by suppressing p53, which is otherwise induced in mice exposed to silica. The process involves CSP-mediated inhibition of serine-15 phosphorylation of p53 by inhibition of protein phosphatase 2A-C (PP2A-C) interaction with silica-induced caveolin-1 in AECs. These observations suggest that changes in the p53–uPA fibrinolytic system cross-talk contribute to lung injury caused by inhalation of silica dust containing crystalline quartz and is protected by CSP by targeting this pathway. - Highlights: • Chronic exposure to quartz dusts is a major cause of lung injury and silicosis. • The survival of patients with silicosis is bleak due to lack of effective treatments. • This study defines a new role of

  5. Muscle thickness correlates to muscle cross sectional area in the assessment of strength training induced hypertrophy.

    PubMed

    Franchi, Martino V; Longo, Stefano; Mallinson, Joanne; Quinlan, Jonathan I; Taylor, Tariq; Greenhaff, Paul L; Narici, Marco V

    2017-08-14

    Muscle thickness (MT) measured by ultrasound has been used to estimate cross-sectional area (measured by CT and MRI) at a single time-point. We tested whether MT could be used as a valid marker of MRI determined muscle anatomical cross-sectional area (ACSA) and volume changes following resistance training (RT). Nine healthy, young, male volunteers (24±2 y.o., BMI 24.1±2.8 kg/m(2) ) had vastus lateralis (VL) muscle volume (VOL) and ACSA mid (at 50% of femur length, FL) assessed by MRI, and VL MT measured by ultrasound at 50% FL. Measurements were taken at baseline and after 12 weeks of isokinetic RT. Differences between baseline and post-training were assessed by Student's paired t-test. The relationships between MRI and ultrasound measurements were tested by Pearson's correlation. After RT, MT increased by 7.5±6.1% (p<0.001), ACSAmid by 5.2±5% (p<0.001) and VOL by 5.0±6.9% (p<0.05) (values: means±S.D.). Positive correlations were found, at baseline and 12 weeks, between MT and ACSAmid (r=0.82, p<0.001 and r=0.73, p<0.001, respectively), and between MT and VOL (r=0.76, p < 0.001 and r=0.73, p < 0.001, respectively). The % change in MT with training was correlated with % change in ACSAmid (r=0.69, p = 0.01), but not % change in VOL (r= 0.33, p>0.05). These data support evidence that MT is a reliable index of muscle ACSAmid and VOL at a single time-point. MT changes following RT are associated with parallel changes in muscle ACSAmid but not with the changes in VOL, highlighting the impact of RT on regional hypertrophy. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  6. Cross-Species Analysis of Nicotine-Induced Proteomic Alterations in Pancreatic Cells

    PubMed Central

    Paulo, Joao A.; Urrutia, Raul; Kadiyala, Vivek; Banks, Peter

    2014-01-01

    Background Toxic compounds in tobacco, such as nicotine, may have adversely affect pancreatic function. We aim to determine nicotine-induced protein alterations in pancreatic cells, which may reveal a link between nicotine exposure and pancreatic disease. Methods We compared the proteomic alterations induced by nicotine treatment in cultured pancreatic cells (mouse, rat and human stellate cells and human duct cells) using mass spectrometry-based techniques, specifically GeLC-MS/MS and spectral counting. Results We identified thousands of proteins in pancreatic cells, hundreds of which were identified exclusively or in higher abundance in either nicotine-treated or untreated cells. Inter-species comparisons of stellate cell proteins revealed several differentially-abundant proteins (in nicotine treated versus untreated cells) common among the 3 species. Proteins appearing in all nicotine-treated stellate cells include amyloid beta (A4), procollagen type VI alpha 1, integral membrane protein 2B,and Toll interacting protein. Conclusions Proteins which were differentially expressed upon nicotine treatment across cell lines, were enriched in certain pathways, including nAChR, cytokine, and integrin signaling. At this analytical depth, we conclude that similar pathways are affected by nicotine, but alterations at the protein level among stellate cells of different species vary. Further interrogation of such pathways will lead to insights into the potential effect of nicotine on pancreatic cells at the biomolecular level and the extension of this concept to the effect of nicotine on pancreatic disease. PMID:23456891

  7. Intimate partner violence and repeat induced abortion in Italy: A cross sectional study.

    PubMed

    Citernesi, Angela; Dubini, Valeria; Uglietti, Anna; Ricci, Elena; Cipriani, Sonia; Parazzini, Fabio

    2015-01-01

    To investigate the impact of intimate partner violence (IPV) on the risk of repeat induced abortion (RIA), we compared IPV history among women with and without previous induced abortion (IA). All consecutive women aged 18 years or more requiring IA in 12 Italian abortion clinics were eligible for inclusion in the study. They were asked to fill in an anonymous, self-developed questionnaire assessing sociodemographic data and their history of different types of violence and related risk factors. The analysis included 1030 women, 624 (60.6%) of whom reported a previous IA. Past or current IPV was reported by 19.3%: 7.0% reported sexual violence, 11.3% physical abuse and 12.1% psychological abuse. Past or current IPV was reported by 22.3% of women with RIA and 14.8% of those undergoing their first IA (adjusted odds ratio 1.57, 95% confidence interval 1.07-2.30; p = 0.02). When we considered sexual, psychological and physical abuse separately, we found that any kind of abuse was more frequent in women with RIA than in women with no previous IA. This study underlines the impact of IPV on the risk of RIA and suggests the need for screening for IPV among women requiring abortion, in order to identify women at risk of RIA and to improve their general and reproductive health.

  8. Stress induced cross-protection against environmental challenges on prokaryotic and eukaryotic microbes.

    PubMed

    Rangel, Drauzio E N

    2011-06-01

    Prokaryotic and eukaryotic microbes thrive successfully in stressful environments such as high osmolarity, acidic or alkali, solar heat and u.v. radiation, nutrient starvation, oxidative stress, and several others. To live under these continuous stress conditions, these microbes must have mechanisms to protect their proteins, membranes, and nucleic acids, as well as other mechanisms that repair nucleic acids. The stress responses in bacteria are controlled by master regulators, which include alternative sigma factors, such as RpoS and RpoH. The sigma factor RpoS integrates multiple signals, such as the general stress response regulators and the sigma factor RpoH regulates the heat shock proteins. These response pathways extensively overlap and are induced to various extents by the same environmental stresses. In eukaryotes, two major pathways regulate the stress responses: stress proteins, termed heat shock proteins (HSP), which appear to be required only for growth during moderate stress, and stress response elements (STRE), which are induced by different stress conditions and these elements result in the acquisition of a tolerant state towards any stress condition. In this review, the mechanisms of stress resistance between prokaryotic and eukaryotic microbes will be described and compared.

  9. Neutron-Induced Partial γ-ray Cross-Section Measurements on Cu, Ge and Pb

    NASA Astrophysics Data System (ADS)

    Kwan, E.; Esterline, J. H.; Fallin, B.; Howell, C. R.; Hutcheson, A.; Kidd, M. F.; Tonchev, A.; Tornow, W.; Karwowski, H. J.; Kelley, J. H.; Mei, D. M.

    2008-10-01

    In high-precision low-statistic measurements such as those carried out in deep underground low-background environments, naturally-occurring radiation can obscure the region of interest. For example, energetic neutrons produced from natural radioactivity or muon-induced reactions will interact with the experimental apparatus producing a continuous background. A survey of neutron-induced γ-ray transitions in ^natCu, enriched ^76Ge, and ^natPb from 150-4000 keV was carried out at TUNL using pulsed mono-energetic neutron beams, with an emphasis on the region around 2039 keV where the 0νββ decay peak of ^76Ge is expected to appear. Transitions at 2041, 2615, and 3062 keV in the shielding materials of Pb and Cu may either directly interfere with the ^76Ge 0νββ peak at 2039 keV or may produce nearby escape peaks. The rates at which these background peaks occur are needed to determine whether events due to 0νββ decay are observed and whether neutrinos are indeed their own anti-particles.

  10. Cross Section Morphology of the Scratch Induced Cracks in Soda-Lime-Silica Glass

    NASA Astrophysics Data System (ADS)

    Matsuoka, Jun; Guo, Danwei; Yoshida, Satoshi

    2017-03-01

    Scratch-induced cracking is a serious problem for the use of glass products. At the scratch process, both median (vertical to the glass surface) and lateral (horizontal to the glass surface) cracks are formed. In this study, morphology of the scratch-induced cracks in a commercial soda-lime-silica glass was investigated by the scanning electron microscopy for the specimen broken across the scratch groove. Scratch test was carried out using a Knoop indenter in water and in dehydrated heptane. When scratch speed was 70 x 10-6 ms-1, length of both vertical and horizontal cracks was proportional to the normal load at scratching, and environmental dependence was not observed. When scratch speed was increased with the constant normal load of 200g, length of both cracks was decreased. In the case of horizontal crack, no environmental effect was observed. On the other hand, length of the vertical crack scratched in water was much longer than that in heptane. At very high scratch speed as high as 1000 x 10-6 ms-1, no vertical crack was formed in the heptane. These differences between horizontal and vertical cracks should be due to the differences of crack initiation position and the influence of subcritical crack growth to these cracks.

  11. Individual differences are critical in determining modafinil-induced behavioral sensitization and cross-sensitization with methamphetamine in mice.

    PubMed

    Soeiro, Aline da Costa; Moreira, Karin Di Monteiro; Abrahao, Karina Possa; Quadros, Isabel Marian Hartmann; Oliveira, Maria Gabriela Menezes

    2012-08-01

    Modafinil is a non-amphetaminic psychostimulant used therapeutically for sleep and psychiatric disorders. However, some studies indicate that modafinil can have addictive properties. The present study examined whether modafinil can produce behavioral sensitization in mice, an experience and drug-dependent behavioral adaptation, and if individual differences play a role in this process. We further tested context-related factors and cross-sensitization between modafinil and methamphetamine. Important individual differences in the behavioral sensitization of Swiss Albino mice were observed after repeated administration of 50 mg/kg modafinil (Experiment 1), or 1 mg/kg methamphetamine (Experiment 2). Only mice classified as sensitized subgroup developed clear behavioral sensitization to the drugs. After a withdrawal period, mice received challenges of modafinil (Experiment 1), or methamphetamine (Experiment 2) and locomotor activity was evaluated in the activity cages (previous context) and in the open field arena (new context) in order to evaluate the context dependency of behavioral sensitization. The expression of sensitization to modafinil, but not to methamphetamine, was affected by contextual testing conditions, since modafinil-sensitized mice only expressed sensitization in the activity cage, but not in the open field. Subsequently, locomotor cross-sensitization between methamphetamine and modafinil was assessed by challenging modafinil-pretreated mice with 1mg/kg methamphetamine (Experiment 1), and methamphetamine-pretreated mice with 50mg/kg modafinil (Experiment 2). We observed a symmetrical cross-sensitization between the drugs only in those mice that were classified as sensitized subgroup. Our findings indicate that repeated exposure to modafinil induces behavioral sensitization only in some animals by similar neurobiological, but not contextual, mechanisms to those of methamphetamine. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Cross sections of proton-induced nuclear reactions on bismuth and lead up to 100 MeV

    NASA Astrophysics Data System (ADS)

    Mokhtari Oranj, L.; Jung, N. S.; Bakhtiari, M.; Lee, A.; Lee, H. S.

    2017-04-01

    Production cross sections of 209Bi(p , x n )207,206,205,204,203Po, 209Bi(p , pxn) 207,206,205,204,203,202Bi, and natPb(p , x n ) 206,205,204,203,202,201Bi reactions were measured to fill the gap in the excitation functions up to 100 MeV as well as to figure out the effects of different nuclear properties on proton-induced reactions including heavy nuclei. The targets were arranged in two different stacks consisting of Bi, Pb, Al, Au foils and Pb plates. The proton beam intensity was determined by the activation analysis method using 27Al(p ,3 p n )24Na, 197Au(p ,p n )196Au, and 197Au(p , p 3 n )194Au monitor reactions in parallel as well as the Gafchromic film dosimetry method. The activities of produced radionuclei in the foils were measured by the HPGe spectroscopy system. Over 40 new cross sections were measured in the investigated energy range. A satisfactory agreement was observed between the present experimental data and the previously published data. Excitation functions of mentioned reactions were calculated by using the theoretical model based on the latest version of the TALYS code and compared to the new data as well as with other data in the literature. Additionally, the effects of various combinations of the nuclear input parameters of different level density models, optical model potentials, and γ-ray strength functions were considered. It was concluded that if certain level density models are used, the calculated cross sections could be comparable to the measured data. Furthermore, the effects of optical model potential and γ-ray strength functions were considerably lower than that of nuclear level densities.

  13. Cross-flows in observation boreholes induced by distant pumping of basalt aquifers: Eastern Snake River Plain, Idaho

    SciTech Connect

    Bennecke, W.M.; Wood, S.H. ); Olsen, J.; Barrash, W. )

    1993-04-01

    Vertical flow velocities up to 20 ft/minute occur in borehole between stratified permeable zones of basalt aquifers of the eastern Snake River Plain. Water is transferred vertically in wells across relatively impermeable zones 35 to 65 ft thick between permeable zones 515 feet deep and a zone 550 to 575 ft deep. Large rates of cross flows are caused by a well 2,000 feet distant which pumps 3,100 gallons/minute with a 2.0 hour on and a 3.5 hour off cycle. Impeller flow-meter logging shows the pump cycle produces reversals in flow direction within 120 seconds of pump switching. Preliminary results from packer isolation of the 500--515 ft zone indicates flow is induced by a hydraulic-head difference between permeable zones set up within 14 seconds of the pump turning on in the distant well. Distant pumping induces downward flow in the observation well, indicating the lower zone has a better connection to the pumped zone. When the pump is off, flow is upward at a lesser rate, suggesting the ambient hydraulic head in this system of aquifers decreases upward. Transmissivity of 1.5 [times] 10[sup 6] gallons/day/ft and storativity of 0.08 from well tests reported by others in this area of the Idaho National Engineering Laboratory do not predict such rapid response times for head changes over a distance of 2,000 feet. The authors suggest that the basalt aquifer system here behaves on a short time scale as a system of confined aquifers with storativity on the order of 10[sup [minus]5] rather than 0.08. The above observations on USGS wells no. 44 and 46 and pumping well CPP-2 show that cross-flow in boreholes provides a vertical path for ground water and contaminant movement between stratified basalt aquifers in the vicinity of the Idaho Chemical Processing Plant.

  14. Simultaneous measurement of neutron-induced fission and capture cross sections for 241Am at neutron energies below fission threshold

    NASA Astrophysics Data System (ADS)

    Hirose, K.; Nishio, K.; Makii, H.; Nishinaka, I.; Ota, S.; Nagayama, T.; Tamura, N.; Goto, S.; Andreyev, A. N.; Vermeulen, M. J.; Gillespie, S.; Barton, C.; Kimura, A.; Harada, H.; Meigo, S.; Chiba, S.; Ohtsuki, T.

    2017-06-01

    Fission and capture reactions were simultaneously measured in the neutron-induced reactions of 241Am at the spallation neutron facility of the Japan Proton Accelerator Research Complex (J-PARC). Data for the neutron energy range of En=0.1-20 eV were taken with the TOF method. The fission events were observed by detecting prompt neutrons accompanied by fission using liquid organic scintillators. The capture reaction was measured by detecting γ rays emitted in the deexcitation of the compound nuclei using the same detectors, where the prompt fission neutrons and capture γ rays were separated by a pulse shape analysis. The cross sections were obtained by normalizing the relative yields at the first resonance to evaluations or other experimental data. The ratio of the fission to capture cross sections at each resonance is compared with those from an evaluated nuclear data library and other experimental data. Some differences were found between the present values and the library/literature values at several resonances.

  15. In-plane current induced domain wall nucleation and its stochasticity in perpendicular magnetic anisotropy Hall cross structures

    NASA Astrophysics Data System (ADS)

    Sethi, P.; Murapaka, C.; Lim, G. J.; Lew, W. S.

    2015-11-01

    Hall cross structures in magnetic nanowires are commonly used for electrical detection of magnetization reversal in which a domain wall (DW) is conventionally nucleated by a local Oersted field. In this letter, we demonstrate DW nucleation in Co/Ni perpendicular magnetic anisotropy nanowire at the magnetic Hall cross junction. The DWs are nucleated by applying an in-plane pulsed current through the nanowire without the need of a local Oersted field. The change in Hall resistance, detected using anomalous Hall effect, is governed by the magnetic volume switched at the Hall junction, which can be tuned by varying the magnitude of the applied current density and pulse width. The nucleated DWs are driven simultaneously under the spin transfer torque effect when the applied current density is above a threshold. The possibility of multiple DW generation and variation in magnetic volume switched makes nucleation process stochastic in nature. The in-plane current induced stochastic nature of DW generation may find applications in random number generation.

  16. Crossed Cerebellar Atrophy of the Lateral Cerebellar Nucleus in an Endothelin-1-Induced, Rodent Model of Ischemic Stroke

    PubMed Central

    Chan, Hugh H.; Cooperrider, Jessica L.; Park, Hyun-Joo; Wathen, Connor A.; Gale, John T.; Baker, Kenneth B.; Machado, Andre G.

    2017-01-01

    Crossed cerebellar diaschisis (CCD) is a functional deficit of the cerebellar hemisphere resulting from loss of afferent input consequent to a lesion of the contralateral cerebral hemisphere. It is manifested as a reduction of metabolism and blood flow and, depending on severity and duration, it can result in atrophy, a phenomenon known as crossed cerebellar atrophy (CCA). While CCA has been well-demonstrated in humans, it remains poorly characterized in animal models of stroke. In this study we evaluated the effects of cerebral cortical ischemia on contralateral cerebellar anatomy using an established rodent model of chronic stroke. The effects of cortical ischemia on the cerebellar hemispheres, vermis and deep nuclei were characterized. Intracortical microinjections of endothelin-1 (ET-1) were delivered to the motor cortex of Long Evans rats to induce ischemic stroke, with animals sacrificed 6 weeks later. Naive animals served as controls. Cerebral sections and cerebellar sections including the deep nuclei were prepared for analysis with Nissl staining. Cortical ischemia was associated with significant thickness reduction of the molecular layer at the Crus 1 and parafloccular lobule (PFL), but not in fourth cerebellar lobule (4Cb), as compared to the ipsilesional cerebellar hemisphere. A significant reduction in volume and cell density of the lateral cerebellar nucleus (LCN), the rodent correlate of the dentate nucleus, was also noted. The results highlight the relevance of corticopontocerebellar (CPC) projections for cerebellar metabolism and function, including its direct projections to the LCN. PMID:28261086

  17. In-plane current induced domain wall nucleation and its stochasticity in perpendicular magnetic anisotropy Hall cross structures

    SciTech Connect

    Sethi, P.; Murapaka, C.; Lim, G. J.; Lew, W. S.

    2015-11-09

    Hall cross structures in magnetic nanowires are commonly used for electrical detection of magnetization reversal in which a domain wall (DW) is conventionally nucleated by a local Oersted field. In this letter, we demonstrate DW nucleation in Co/Ni perpendicular magnetic anisotropy nanowire at the magnetic Hall cross junction. The DWs are nucleated by applying an in-plane pulsed current through the nanowire without the need of a local Oersted field. The change in Hall resistance, detected using anomalous Hall effect, is governed by the magnetic volume switched at the Hall junction, which can be tuned by varying the magnitude of the applied current density and pulse width. The nucleated DWs are driven simultaneously under the spin transfer torque effect when the applied current density is above a threshold. The possibility of multiple DW generation and variation in magnetic volume switched makes nucleation process stochastic in nature. The in-plane current induced stochastic nature of DW generation may find applications in random number generation.

  18. Determination of Stark parameters by cross-calibration in a multi-element laser-induced plasma

    NASA Astrophysics Data System (ADS)

    Liu, Hao; Truscott, Benjamin S.; Ashfold, Michael N. R.

    2016-05-01

    We illustrate a Stark broadening analysis of the electron density Ne and temperature Te in a laser-induced plasma (LIP), using a model free of assumptions regarding local thermodynamic equilibrium (LTE). The method relies on Stark parameters determined also without assuming LTE, which are often unknown and unavailable in the literature. Here, we demonstrate that the necessary values can be obtained in situ by cross-calibration between the spectral lines of different charge states, and even different elements, given determinations of Ne and Te based on appropriate parameters for at least one observed transition. This approach enables essentially free choice between species on which to base the analysis, extending the range over which these properties can be measured and giving improved access to low-density plasmas out of LTE. Because of the availability of suitable tabulated values for several charge states of both Si and C, the example of a SiC LIP is taken to illustrate the consistency and accuracy of the procedure. The cross-calibrated Stark parameters are at least as reliable as values obtained by other means, offering a straightforward route to extending the literature in this area.

  19. Determination of Stark parameters by cross-calibration in a multi-element laser-induced plasma

    PubMed Central

    Liu, Hao; Truscott, Benjamin S.; Ashfold, Michael N. R.

    2016-01-01

    We illustrate a Stark broadening analysis of the electron density Ne and temperature Te in a laser-induced plasma (LIP), using a model free of assumptions regarding local thermodynamic equilibrium (LTE). The method relies on Stark parameters determined also without assuming LTE, which are often unknown and unavailable in the literature. Here, we demonstrate that the necessary values can be obtained in situ by cross-calibration between the spectral lines of different charge states, and even different elements, given determinations of Ne and Te based on appropriate parameters for at least one observed transition. This approach enables essentially free choice between species on which to base the analysis, extending the range over which these properties can be measured and giving improved access to low-density plasmas out of LTE. Because of the availability of suitable tabulated values for several charge states of both Si and C, the example of a SiC LIP is taken to illustrate the consistency and accuracy of the procedure. The cross-calibrated Stark parameters are at least as reliable as values obtained by other means, offering a straightforward route to extending the literature in this area. PMID:27170026

  20. Early Cross-Modal Interactions in Auditory and Visual Cortex Underlie a Sound-Induced Visual Illusion

    PubMed Central

    Mishra, Jyoti; Martinez, Antigona; Sejnowski, Terrence J.; Hillyard, Steven A.

    2010-01-01

    When a single flash of light is presented interposed between two brief auditory stimuli separated by 60 –100 ms, subjects typically report perceiving two flashes (Shams et al., 2000, 2002). We investigated the timing and localization of the cortical processes that underlie this illusory flash effect in 34 subjects by means of 64-channel recordings of event-related potentials (ERPs). A difference ERP calculated to isolate neural activity associated with the illusory second flash revealed an early modulation of visual cortex activity at 30 – 60 ms after the second sound, which was larger in amplitude in subjects who saw the illusory flash more frequently. These subjects also showed this early modulation in response to other combinations of auditory and visual stimuli, thus pointing to consistent individual differences in the neural connectivity that underlies cross-modal integration. The overall pattern of cortical activity associated with the cross-modally induced illusory flash, however, differed markedly from that evoked by a real second flash. A trial-by-trial analysis showed that short-latency ERP activity localized to auditory cortex and polymodal cortex of the temporal lobe, concurrent with gamma bursts in visual cortex, were associated with perception of the double-flash illusion. These results provide evidence that perception of the illusory second flash is based on a very rapid dynamic interplay between auditory and visual cortical areas that is triggered by the second sound. PMID:17428990

  1. Neutron-induced fission cross section measurements for uranium isotopes {sup 236}U and {sup 234}U at LANSCE

    SciTech Connect

    Laptev, A. B.; Tovesson, F.; Hill, T. S.

    2013-04-19

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R and D). The incident neutron energy range spans from sub-thermal up to 200 MeV by combining two LANSCE facilities, the Lujan Center and the Weapons Neutron Research facility (WNR). The time-of-flight method is implemented to measure the incident neutron energy. A parallel-plate fission ionization chamber was used as a fission fragment detector. The event rate ratio between the investigated foil and a standard {sup 235}U foil is converted into a fission cross section ratio. In addition to previously measured data new measurements include {sup 236}U data which is being analyzed, and {sup 234}U data acquired in the 2011-2012 LANSCE run cycle. The new data complete the full suite of Uranium isotopes which were investigated with this experimental approach. Obtained data are presented in comparison with existing evaluations and previous data.

  2. Influences of the helical strake cross-section shape on vortex-induced vibrations suppression for a long flexible cylinder

    NASA Astrophysics Data System (ADS)

    Xu, Wan-hai; Luan, Ying-sen; Liu, Li-qin; Wu, Ying-xiang

    2017-08-01

    An experimental study on a bare flexible cylinder as well as cylinders fitted with two types of cross-sectioned helical strakes was carried out in a towing tank. The main purpose of this paper is to investigate the effects of strakes' crosssection on the vortex-induced vibrations (VIV) suppression of a flexible cylinder. The square-sectioned and roundsectioned helical strakes were selected in the experimental tests. The uniform current was generated by towing the cylinder models along the tank using a towing carriage. The Reynolds number was in the range of 800-16000. The strain responses were measured by the strain gages in cross-flow (CF) and in-line (IL) directions. A modal analysis method was adopted to obtain the displacement responses using the strain signals in different measurement positions. The comparison of the experimental results among the bare cylinder, square-sectioned straked cylinder and roundsectioned straked cylinder was performed. The helical strakes can effectively reduce the strain amplitude, displacement amplitude, response frequencies and dominant modes of a flexible cylinder excited by VIV. And the mean drag coefficients of straked cylinders were approximately consistent with each other. In addition, the squaresectioned and round-sectioned strakes nearly share the similar VIV reduction behaviors. Sometimes, the strakes with round-section represent more excellent effects on the VIV suppression of response frequency than those with squaresection.

  3. Cross sections for α-particle induced reactions on Sn115,116 around the Coulomb barrier

    NASA Astrophysics Data System (ADS)

    Filipescu, D.; Avrigeanu, V.; Glodariu, T.; Mihai, C.; Bucurescu, D.; Ivaşcu, M.; Căta-Danil, I.; Stroe, L.; Sima, O.; Căta-Danil, G.; Deleanu, D.; Ghiţă, D. G.; Mărginean, N.; Mărginean, R.; Negret, A.; Pascu, S.; Sava, T.; Suliman, G.; Zamfir, N. V.

    2011-06-01

    The cross sections of the Sn115(α,γ)Te119, Sn115(α,n)Te118, and Sn116(α,n)Te119 reactions (both on ground and isomeric states) have been measured at effective center-of-mass energies from 9.3 to 14.8 MeV. During a first experiment, enriched self-supporting Sn115 (51.2%) + Sn116 (24.4%) foils were bombarded with an α beam delivered by the Bucharest IFIN-HH Tandem Accelerator. In a second experiment, a highly enriched Sn116 target was irradiated in order to disentangle the experimental cross section contributions due to Sn115(α,γ)Te119 and Sn115(α,n)Te118 reactions obtained in the first measurement. The beam-induced activity was measured with two large volume HPGe detectors in close geometry. The experimental results were compared with theoretical predictions obtained in the framework of the statistical model.

  4. Probabilistic modeling of shear-induced formation and breakage of doublets cross-linked by receptor-ligand bonds.

    PubMed

    Long, M; Goldsmith, H L; Tees, D F; Zhu, C

    1999-02-01

    A model was constructed to describe previously published experiments of shear-induced formation and breakage of doublets of red cells and of latexes cross-linked by receptor-ligand bonds (. Biophys. J. 65:1318-1334; Tees and Goldsmith. 1996. Biophys. J. 71:1102-1114;. Biophys. J. 71:1115-1122). The model, based on McQuarrie's master equations (1963. J. Phys. Chem. 38:433-436), provides unifying treatments for three distinctive time periods in the experiments of particles in a Couette flow in which a doublet undergoes 1) formation upon two-body collision between singlets; 2) evolution of bonds at low shear rate; and 3) break-up at high shear rate. Neglecting the applied force at low shear rate, the probability of forming a doublet per collision as well as the evolution of probability distribution of bonds in a preformed doublet were solved analytically and found to be in quite good agreement with measurements. At high shear rate with significant force acting to accelerate bond dissociation, the predictions for break-up of doublets were obtained numerically and compared well with data in both individual and population studies. These comparisons enabled bond kinetic parameters for three types of particles cross-linked by two receptor-ligand systems to be calculated, which agreed well with those computed from Monte Carlo simulations. This work can be extended to analyze kinetics of receptor-ligand binding in cell aggregates, such as those of neutrophils and platelets in the circulation.

  5. Porous silicon microparticle potentiates anti-tumor immunity by enhancing cross-presentation and inducing type I interferon response

    PubMed Central

    Xia, Xiaojun; Mai, Junhua; Xu, Rong; Perez, Jorge Enrique Tovar; Guevara, Maria L.; Shen, Qi; Mu, Chaofeng; Tung, Hui-Ying; Corry, David B.; Evans, Scott E.; Liu, Xuewu; Ferrari, Mauro; Zhang, Zhiqiang; Li, Xian Chang; Wang, Rong-fu; Shen, Haifa

    2015-01-01

    SUMMARY Micro- and nano-meter size particles have become popular candidates for cancer vaccine adjuvants. However the mechanism by which such particles enhance immune responses remains unclear. Here we report a porous silicon microparticle (PSM)-based cancer vaccine that greatly enhances cross-presentation and activates type I interferon response in dendritic cells. PSM-loaded antigen exhibited prolonged early endosome localization and enhanced cross-presentation through both proteasome- and lysosome-dependent pathways. Phagocytosis of PSM by dendritic cells induced type I interferon responses through a TRIF- and MAVS-dependent pathway. Dendritic cells primed with PSM-loaded HER2 antigen produced robust CD8 T cell-dependent anti-tumor immunity in mice bearing HER2-positive mammary gland tumors. Importantly, this vaccination activated tumor immune microenvironment with elevated levels of intra-tumor type I interferon and MHC-II expression, abundant CD11c+ dendritic cell infiltration, and tumor-specific cytotoxic T cell responses. These findings highlight the potential for PSM as an immune adjuvant to potentiate dendritic cell-based cancer immunotherapy. PMID:25937283

  6. First upper limits on the radar cross section of cosmic-ray induced extensive air showers

    SciTech Connect

    Abbasi, R. U.; Abe, M.; Abou Bakr Othman, M.; Abu-Zayyad, T.; Allen, M.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Besson, D.; Blake, S. A.; Byrne, M.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Farhang-Boroujeny, B.; Fujii, T.; Fukushima, M.; Gillman, W. H.; Goto, T.; Hanlon, W.; Hanson, J. C.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jayanthmurthy, C.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kunwar, S.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Prohira, S.; Pshirkov, M. S.; Rezazadeh-Reyhani, A.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Schurig, D.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takai, H.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Venkatesh, S.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

    2016-11-19

    TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. Furthermore, the TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary goal of observing the radar signatures of extensive air showers (EAS). Simulations indicate that echoes are expected to be short in duration (~10 µs) and exhibit rapidly changing frequency, with rates on the order 1 MHz/µs. The EAS radar cross-section (RCS) is currently unknown although it is the subject of over 70 years of speculation. One novel signal search technique is described in which the expected radar echo of a particular air shower is used as a matched filter template and compared to waveforms obtained by triggering the radar DAQ using the Telescope Array fluorescence detector. No evidence for the scattering of radio frequency radiation by EAS is obtained to date. Finally, we report the first quantitative RCS upper limits using EAS that triggered the Telescope Array Fluorescence Detector.

  7. First upper limits on the radar cross section of cosmic-ray induced extensive air showers

    DOE PAGES

    Abbasi, R. U.; Abe, M.; Abou Bakr Othman, M.; ...

    2016-11-19

    TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. Furthermore, the TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary goal of observing the radar signatures of extensive air showers (EAS). Simulations indicate that echoes are expected to be short in durationmore » (~10 µs) and exhibit rapidly changing frequency, with rates on the order 1 MHz/µs. The EAS radar cross-section (RCS) is currently unknown although it is the subject of over 70 years of speculation. One novel signal search technique is described in which the expected radar echo of a particular air shower is used as a matched filter template and compared to waveforms obtained by triggering the radar DAQ using the Telescope Array fluorescence detector. No evidence for the scattering of radio frequency radiation by EAS is obtained to date. Finally, we report the first quantitative RCS upper limits using EAS that triggered the Telescope Array Fluorescence Detector.« less

  8. Cross-field electron transport induced by a rotating spoke in a cylindrical Hall thruster

    NASA Astrophysics Data System (ADS)

    Ellison, C. L.; Raitses, Y.; Fisch, N. J.

    2012-01-01

    Rotating spoke phenomena have been observed in a variety of Hall thruster and other E × B devices. It has been suggested that the spoke may be associated with the enhancement of the electron cross-field transport. In this paper, the current conducted across the magnetic field via a rotating spoke has been directly measured for the first time in the E × B discharge of a cylindrical Hall thruster. The spoke current was measured using a segmented anode. Synchronized measurements with a high speed camera and a four-segment anode allow observation of the current as a function of time and azimuthal position. Upwards of 50% of the total current is conducted through the spoke, which occupies a quarter of the Hall thruster channel area. To determine the transport mechanism, emissive and Langmuir probes were installed to measure fluctuating plasma potential, electron density, and temperature. A perturbed, azimuthal electric field and density are observed to oscillate in-phase with the rotating spoke. The resulting drift current is found to enhance electron transport with a magnitude equal to the spoke current to within margins of error.

  9. Surface micromorphology of cross-linked tetrafunctional polylactide scaffolds inducing vessel growth and bone formation.

    PubMed

    Kuznetsova, Daria; Ageykin, Aleksey; Koroleva, Anastasia; Deiwick, Andrea; Shpichka, Anastasia; Solovieva, Anna; Kostjuk, Sergey; Meleshina, Aleksandra; Rodimova, Svetlana; Akovanceva, Anastasia; Butnaru, Denis; Frolova, Anastasia; Zagaynova, Elena; Chichkov, Boris; Bagratashvili, Victor; Timashev, Peter

    2017-03-16

    In the presented study, we have developed a synthetic strategy allowing a gradual variation of a polylactide arms' length, which later influences the micromorphology of the scaffold surface, formed by a two-photon polymerization technique. It has been demonstrated that the highest number of cells is present on the scaffolds with the roughest surface made of the polylactide with longer arms (PLA760), and osteogenic differentiation of mesenchymal stem cells is most pronounced on such scaffolds. According to the results of biological testing, the PLA760 scaffolds were implanted into a created cranial defect in a mouse for an in vivo assessment of the bone tissue formation. The in vivo experiments have shown that, by week 10, deposition of calcium phosphate particles occurs in the scaffold at the defect site, as well as, the formation of a new bone and ingrowth of blood vessels from the surrounding tissues. These results demonstrate that the cross-linked microstructured tetrafunctional polylactide scaffolds are promising microstructures for bone regeneration in tissue engineering.

  10. Heat shock-induced interactions among nuclear HSFs detected by fluorescence cross-correlation spectroscopy

    SciTech Connect

    Pack, Chan-Gi; Ahn, Sang-Gun

    2015-07-31

    The cellular response to stress is primarily controlled in cells via transcriptional activation by heat shock factor 1 (HSF1). HSF1 is well-known to form homotrimers for activation upon heat shock and subsequently bind to target DNAs, such as heat-shock elements, by forming stress granules. A previous study demonstrated that nuclear HSF1 and HSF2 molecules in live cells interacted with target DNAs on the stress granules. However, the process underlying the binding interactions of HSF family in cells upon heat shock remains unclear. This study demonstrate for the first time that the interaction kinetics among nuclear HSF1, HSF2, and HSF4 upon heat shock can be detected directly in live cells using dual color fluorescence cross-correlation spectroscopy (FCCS). FCCS analyses indicated that the binding between HSFs was dramatically changed by heat shock. Interestingly, the recovery kinetics of interaction between HSF1 molecules after heat shock could be represented by changes in the relative interaction amplitude and mobility. - Highlights: • The binding interactions among nuclear HSFs were successfully detected. • The binding kinetics between HSF1s during recovery was quantified. • HSF2 and HSF4 strongly formed hetero-complex, even before heat shock. • Nuclear HSF2 and HSF4 bound to HSF1 only after heat shock.

  11. Analysis of delamination in cross-ply laminates initiating from impact induced matrix cracking

    NASA Technical Reports Server (NTRS)

    Salpekar, S. A.

    1993-01-01

    Two-dimensional finite element analyses of (02/90(8)/02) glass/epoxy and graphite/epoxy composite laminates were performed to investigate some of the characteristics of damage development due to an impact load. A cross section through the thickness of the laminate with fixed ends, and carrying a transverse load in the center, was analyzed. Inclined matrix cracks, such as those produced by a low-velocity impact, were modeled in the 90 deg ply group. The introduction of the matrix cracks caused large interlaminar tensile and shear stresses in the vicinity of both crack tips in the 0/90 and 90/0 interfaces, indicating that matrix cracking may give rise to delamination. The ratio of Mode I to total strain energy release rate, G(I)/G(total), at the beginning of delamination, calculated at the two (top and bottom) matrix crack tips was 60 and 28 percent, respectively, in the glass/epoxy laminate. The corresponding ratio was 97 and 77 percent in the graphite/epoxy laminate. Thus, a significant Mode I component of strain energy release rate may be present at the delamination initiation due to an impact load. The value of strain energy release rate at either crack tip increased due to an increase in the delamination length at the other crack tip and may give rise to an unstable delamination growth under constant load.

  12. Analysis of delamination in cross ply laminates initiating from impact induced matrix cracking

    NASA Technical Reports Server (NTRS)

    Salpekar, S. A.

    1991-01-01

    Several two dimensional finite element analyses of (0 sub 2/90 sub 8/0 sub 2) glass/epoxy and graphite-epoxy composite laminates were performed to study some of the characteristics of damage development due to an impact load. A cross section through the thickness of the laminate with fixed ends, and carrying a transverse load in the center was analyzed. Inclined matrix cracks such as those produced by low velocity impact were modeled in the 90 deg ply group. The introduction of the matrix cracks caused large interlaminar tension and shear stresses in the vicinity of both crack tips in the 0/90 and 90/0 interfaces. The large interlaminar stresses at the ends of the matrix cracks indicate that matrix cracking may give rise to delamination. The ratio of mode I to total strain energy release rate at the beginning of delamination calculated at the two matrix crack tips was 60 and 28 pct., respectively, in the glass/epoxy laminate. The corresponding ratio was 97 and 77 pct. in the graphite-epoxy laminate. Thus, a significant mode I component of strain energy release rate may be present at the delamination initiation due to an impact load.

  13. Treatment of experimentally induced Theileria annulata infection in cross-bred calves with buparvaquone.

    PubMed

    Dhar, S; Malhotra, D V; Bhushan, C; Gautam, O P

    1988-03-01

    Twenty cross-bred (Bos taurus X Bos indicus) calves, 7-21 days old, were infected by a ground-up tick supernate of Hyalomma anatolicum anatolicum infected with the Hisar isolate of Theileria annulata. Six calves acted as untreated controls and they all died of theileriosis within 17 days of infection. The remaining 14 calves were divided into Group A and B, each consisting of seven calves. All the calves of Groups A and B were treated intramuscularly with buparvaquone (BW 720C) on Day 11 post-infection, when clinical signs of theileriosis were apparent. Each calf received 2.5 mg BW 720 C kg-1 body weight as a single injection. In addition, each calf of Group B was given proprietary haematinics by intramuscular injection, daily for 12 days. In Group A, two calves died of cerebral theileriosis and five were clinically cured. However, four of these five calves later died of anaemia. In Group B, all the calves were clinically cured and none died during the observation period of 1 month. The parasitaemia declined to less than 1% within a fortnight of treatment. The initial declines in haemoglobin concentration and packed cell volume were halted and preinfection values were soon restored. No toxic signs attributable to treatment with buparvaquone were observed.

  14. First upper limits on the radar cross section of cosmic-ray induced extensive air showers

    NASA Astrophysics Data System (ADS)

    Abbasi, R. U.; Abe, M.; Abou Bakr Othman, M.; Abu-Zayyad, T.; Allen, M.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Besson, D.; Blake, S. A.; Byrne, M.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Farhang-Boroujeny, B.; Fujii, T.; Fukushima, M.; Gillman, W. H.; Goto, T.; Hanlon, W.; Hanson, J. C.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jayanthmurthy, C.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kunwar, S.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Prohira, S.; Pshirkov, M. S.; Rezazadeh-Reyhani, A.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Schurig, D.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takai, H.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Venkatesh, S.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

    2017-01-01

    TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. The TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary goal of observing the radar signatures of extensive air showers (EAS). Simulations indicate that echoes are expected to be short in duration (∼ 10 μs) and exhibit rapidly changing frequency, with rates on the order 1 MHz/μs. The EAS radar cross-section (RCS) is currently unknown although it is the subject of over 70 years of speculation. A novel signal search technique is described in which the expected radar echo of a particular air shower is used as a matched filter template and compared to waveforms obtained by triggering the radar DAQ using the Telescope Array fluorescence detector. No evidence for the scattering of radio frequency radiation by EAS is obtained to date. We report the first quantitative RCS upper limits using EAS that triggered the Telescope Array Fluorescence Detector.

  15. "Rickettsia amblyommii" induces cross protection against lethal Rocky Mountain spotted fever in a guinea pig model.

    PubMed

    Blanton, Lucas S; Mendell, Nicole L; Walker, David H; Bouyer, Donald H

    2014-08-01

    Rocky Mountain spotted fever (RMSF) is a severe illness caused by Rickettsia rickettsii for which there is no available vaccine. We hypothesize that exposure to the highly prevalent, relatively nonpathogenic "Rickettsia amblyommii" protects against R. rickettsii challenge. To test this hypothesis, guinea pigs were inoculated with "R. amblyommii." After inoculation, the animals showed no signs of illness. When later challenged with lethal doses of R. rickettsii, those previously exposed to "R. amblyommii" remained well, whereas unimmunized controls developed severe illness and died. We conclude that "R. amblyommii" induces an immune response that protects from illness and death in the guinea pig model of RMSF. These results provide a basis for exploring the use of low-virulence rickettsiae as a platform to develop live attenuated vaccine candidates to prevent severe rickettsioses.

  16. Alpha-alumina nanoparticles induce efficient autophagy-dependent cross-presentation and potent antitumour response

    NASA Astrophysics Data System (ADS)

    Li, Haiyan; Li, Yuhuan; Jiao, Jun; Hu, Hong-Ming

    2011-10-01

    Therapeutic cancer vaccination is an attractive strategy because it induces T cells of the immune system to recognize and kill tumour cells in cancer patients. However, it remains difficult to generate large numbers of T cells that can recognize the antigens on cancer cells using conventional vaccine carrier systems. Here we show that α-Al2O3 nanoparticles can act as an antigen carrier to reduce the amount of antigen required to activate T cells in vitro and in vivo. We found that α-Al2O3 nanoparticles delivered antigens to autophagosomes in dendritic cells, which then presented the antigens to T cells through autophagy. Immunization of mice with α-Al2O3 nanoparticles that are conjugated to either a model tumour antigen or autophagosomes derived from tumour cells resulted in tumour regression. These results suggest that α-Al2O3 nanoparticles may be a promising adjuvant in the development of therapeutic cancer vaccines.

  17. Is periodontal health a predictor of drug-induced gingival overgrowth? A cross-sectional study

    PubMed Central

    Banthia, Ruchi; Gupta, Santosh; Banthia, Priyank; Singh, Pallavi; Raje, Sapna; Kaur, Navkiran

    2014-01-01

    Background: Gingival overgrowth is a common side-effect of amlodipine regimen on the oral cavity. There is controversy regarding the cause and effect relationship of periodontal health and drug induced gingival overgrowth. Therefore, this study was conducted to investigate and to assess the relationship between the periodontal health and the onset and severity of gingival overgrowth in hypertensive patients receiving amlodipine. Materials and Methods: A total of 99 known hypertensive patients on amlodipine regimen were included in this study. Probing pocket depth (PPD) and clinical attachment loss (CAL) were noted on four sites of maxillary and mandibular anterior teeth. Gingival enlargement scores were assessed for each patient by employing the hyperplastic index. Oral hygiene status was evaluated using the calculus index (CI). Patients were divided into H, E and L groups based on their periodontal status and responders and non-responders based on their hyperplastic index scores. Differences in means of different periodontal variables in different groups were tested for significance by using ANOVA and unpaired Student t-test. Pearson's correlation coefficient was calculated to assess the correlation between different variables. For all analyses, P < 0.05 was considered to be significant. Results: All the periodontal parameters were statistically highly significant (P = 0.00) amongst H, E and L groups and between responders and non-responders. Statistically highly significant Pearson correlation coefficients were found between mean PPD and mean hyperplastic score, mean CAL and mean hyperplastic score and mean calculus and mean hyperplastic score. Conclusion: The results of this study indicated a definite association between periodontal health and development and severity of amlodipine-induced gingival overgrowth PMID:25426150

  18. Photolon™ --photosensitization induces apoptosis via ROS-mediated cross-talk between mitochondria and lysosomes.

    PubMed

    Ali-Seyed, Mohamed; Bhuvaneswari, Ramaswamy; Soo, Khee Chee; Olivo, Malini

    2011-10-01

    The localization of photosensitizers in the subcellular compartments during photodynamic therapy (PDT) plays a major role in the cell destruction; therefore, the aim of this study was to investigate the intracellular localization of Chlorin e6-PVP (Photolon™) in malignant and normal cells. Our study involves the characterization of the structural determinants of subcellular localization of Photolon, and how subcellular localization affects the selective toxicity of Photolon towards tumor cells. Using confocal laser scanning microscopy (CLSM) and fluorescent organelle probes; we examined the subcellular localization of Photolon™ in the murine colon carcinoma CT-26 and normal fibroblast (NHLC) cells. Our results demonstrated that after 30 min of incubation, the distribution of Photolon was localized mainly in the cytoplasmic organelles including the mitochondria, lysosomes, Golgi apparatus, around the nuclear envelope and also in the nucleus but not in the endo-plasmic reticulum whereas in NHLC cells, Photolon was found to be localized minimally only in the nucleus not in other organelles studied. The relationship between subcellular localization of Photolon and PDT-induced apoptosis was investigated. Apoptotic cell death was judged by the formation of known apoptotic hallmarks including, the phosphatidylserine externalization (PS), PARP cleavage, a substrate for caspase-3 and the formation of apoptotic nuclei. At the irradiation dose of 1 J/cm2, the percentage of apoptotic cells was 80%, respectively. This study provided substantial evidence that Photolon preferentially localized in the subcellular organelles in the following order: nucleus, mitochondria, lysosomes and the Golgi apparatus and subsequent photodamage of the mitochondria and lyso-somes played an important role in PDT-mediated apoptosis CT-26 cells. Our results based on the cytoplasmic organelles and the intranuclear localization extensively enhance the efficacy of PDT with appropriate

  19. Loosening of globular structure under alkaline pH affects accessibility of β-lactoglobulin to tyrosinase-induced oxidation and subsequent cross-linking.

    PubMed

    Partanen, Riitta; Torkkeli, Mika; Hellman, Maarit; Permi, Perttu; Serimaa, Ritva; Buchert, Johanna; Mattinen, Maija-Liisa

    2011-07-10

    Globular proteins such as β-lactoglobulin (BLG) are poorly accessible to enzymes. We have studied susceptibility of BLG to oxidation by Trichoderma reesei (TrTyr) and Agaricus bisporus (AbTyr) tyrosinases and subsequent intermolecular cross-linking with respect to pH-induced structural changes. We evaluated pH-induced structural changes in BLG using circular dichroism, tryptophan fluorescence and small angle X-ray scattering (SAXS) measurements, where after these results were correlated with the analysis of cross-linking by sodium dodecyl sulphate polyacrylamide gel electrophoresis. Oxygen consumption measurement and changes in radii of gyration determined by SAXS during the enzyme-induced oxidation at the respective reaction conditions were also followed. Intermolecular cross-linking of BLG by TrTyr was found at pH 9 but not at pH 7.5. AbTyr was unable to catalyze cross-linking at pH 7.5 or pH 9. Increased accessibility and cross-linking by TrTyr was addressed to loosening of the three dimensional structure of the protein, increased flexibility of the backbone as well as partial hydrolysis. In addition to basic research of the effect of protein folding on enzymatic cross-linking the research results have significance on the exploitation of TrTyr at alkaline conditions. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. The DE and FG loops of the HPV major capsid protein contribute to the epitopes of vaccine-induced cross-neutralising antibodies

    PubMed Central

    Bissett, Sara L.; Godi, Anna; Beddows, Simon

    2016-01-01

    The human papillomavirus (HPV) vaccines consist of major capsid protein (L1) virus-like particles (VLP) and are highly efficacious against the development of cervical cancer precursors attributable to oncogenic genotypes, HPV16 and HPV18. A degree of vaccine-induced cross-protection has also been demonstrated against genetically-related genotypes in the Alpha-7 (HPV18-like) and Alpha-9 (HPV16-like) species groups which is coincident with the detection of L1 cross-neutralising antibodies. In this study the L1 domains recognised by inter-genotype cross-neutralising antibodies were delineated. L1 crystallographic homology models predicted a degree of structural diversity between the L1 loops of HPV16 and the non-vaccine Alpha-9 genotypes. These structural predictions informed the design of chimeric pseudovirions with inter-genotype loop swaps which demonstrated that the L1 domains recognised by inter-genotype cross-neutralising antibodies comprise residues within the DE loop and the late region of the FG loop. These data contribute to our understanding of the L1 domains recognised by vaccine-induced cross-neutralising antibodies. Such specificities may play a critical role in vaccine-induced cross-protection. PMID:28004837

  1. The DE and FG loops of the HPV major capsid protein contribute to the epitopes of vaccine-induced cross-neutralising antibodies.

    PubMed

    Bissett, Sara L; Godi, Anna; Beddows, Simon

    2016-12-22

    The human papillomavirus (HPV) vaccines consist of major capsid protein (L1) virus-like particles (VLP) and are highly efficacious against the development of cervical cancer precursors attributable to oncogenic genotypes, HPV16 and HPV18. A degree of vaccine-induced cross-protection has also been demonstrated against genetically-related genotypes in the Alpha-7 (HPV18-like) and Alpha-9 (HPV16-like) species groups which is coincident with the detection of L1 cross-neutralising antibodies. In this study the L1 domains recognised by inter-genotype cross-neutralising antibodies were delineated. L1 crystallographic homology models predicted a degree of structural diversity between the L1 loops of HPV16 and the non-vaccine Alpha-9 genotypes. These structural predictions informed the design of chimeric pseudovirions with inter-genotype loop swaps which demonstrated that the L1 domains recognised by inter-genotype cross-neutralising antibodies comprise residues within the DE loop and the late region of the FG loop. These data contribute to our understanding of the L1 domains recognised by vaccine-induced cross-neutralising antibodies. Such specificities may play a critical role in vaccine-induced cross-protection.

  2. Durability of Vaccine-Induced Immunity Against Tetanus and Diphtheria Toxins: A Cross-sectional Analysis

    PubMed Central

    Hammarlund, Erika; Thomas, Archana; Poore, Elizabeth A.; Amanna, Ian J.; Rynko, Abby E.; Mori, Motomi; Chen, Zunqiu; Slifka, Mark K.

    2016-01-01

    Background. Many adult immunization schedules recommend that tetanus and diphtheria vaccination be performed every 10 years. In light of current epidemiological trends of disease incidence and rates of vaccine-associated adverse events, the 10-year revaccination schedule has come into question. Methods. We performed cross-sectional analysis of serum antibody titers in 546 adult subjects stratified by age or sex. All serological results were converted to international units after calibration with international serum standards. Results. Approximately 97% of the population was seropositive to tetanus and diphtheria as defined by a protective serum antibody titer of ≥0.01 IU/mL. Mean antibody titers were 3.6 and 0.35 IU/mL against tetanus and diphtheria, respectively. Antibody responses to tetanus declined with an estimated half-life of 14 years (95% confidence interval, 11–17 years), whereas antibody responses to diphtheria were more long-lived and declined with an estimated half-life of 27 years (18–51 years). Mathematical models combining antibody magnitude and duration predict that 95% of the population will remain protected against tetanus and diphtheria for ≥30 years without requiring further booster vaccination. Conclusions. These studies demonstrate that durable levels of protective antitoxin immunity exist in the majority of vaccinated individuals. Together, this suggests that it may no longer be necessary to administer booster vaccinations every 10 years and that the current adult vaccination schedule for tetanus and diphtheria should be revisited. PMID:27060790

  3. Anthrax Vaccine Induced Antibodies Provide Cross-Species Prediction of Survival to Aerosol Challenge

    PubMed Central

    Fay, Michael P.; Follmann, Dean A.; Lynn, Freyja; Schiffer, Jarad M.; Stark, Greg; Kohberge, Robert; Quinn, Conrad P.; Nuzum, Edwin O.

    2013-01-01

    Because clinical trials to assess the efficacy of vaccines against anthrax are not ethical or feasible, licensure for new anthrax vaccines will likely involve the Food and Drug Administration’s “Animal Rule,” a set of regulations that allow approval of products based on efficacy data only in animals combined with immunogenicity and safety data in animals and humans. US government sponsored animal studies have shown anthrax vaccine efficacy in a variety of settings. We examined data from 21 of those studies to determine if an immunological bridge based on lethal toxin neutralization activity assay (TNA) can predict survival against an inhalation anthrax challenge within and across species and genera. The 21 studies were classified into 11 different settings, each of which had the same animal species, vaccine type and formulation, vaccination schedule, time of TNA measurement, and challenge time. Logistic regression models determined the contribution of vaccine dilution dose and TNA on prediction of survival. For most settings, logistic models using only TNA explained more than 75% of the survival effect of the models with dose additionally included. Cross species survival predictions using TNA were compared to the actual survival and shown to have good agreement (Cohen’s κ ranged from 0.55 to 0.78). In one study design, cynomolgus macaque data predicted 78.6% survival in rhesus macaques (actual survival 83.0%) and 72.6% in rabbits (actual survival, 64.6%). These data add support for the use of TNA as an immunological bridge between species to extrapolate data in animals to predict anthrax vaccine effectiveness in humans. PMID:22972844

  4. Evaluation of cross sections for neutron-induced reactions in sodium. [10/sup -5/ eV to 20 MeV

    SciTech Connect

    Larson, D.C.

    1980-09-01

    An evaluation of the neutron-induced cross sections of /sup 23/Na has been done for the energy range from 10/sup -5/ eV to 20 MeV. All significant cross sections are given, including differential cross sections for production of gamma rays. The recommended values are based on experimental data where available, and use results of a consistent model code analysis of available data to predict cross sections where there are no experimental data. This report describes the evaluation that was submitted to the Cross Section Evaluation Working Group (CSEWG) for consideration as a part of the Evaluated Nuclear Data File, Version V, and subsequently issued as MAT 1311. 126 references, 130 figures, 14 tables.

  5. Proton and Helium Induced L Subshell Ionization Cross-Section Measurements of Medium to High Z Atoms

    NASA Astrophysics Data System (ADS)

    Harrigan, Mark Francis

    This thesis deals with the L subshell ionization of medium to high atomic number (Z) targets by proton and He('+) ion bombardment, and the subsequent filling of the inner shell vacancy by the production of X-rays. The L subshell ionization cross sections for antimony (Z = 51), gadolinium (Z = 64), tungsten (Z = 74) and gold (Z = 79) were measured for 0.6-2.0 MeV proton and He('+) ion bombardment, and targets of antimony and gadolinium were bombarded with 90 to 200 keV protons. Energy dispersive Si(Li) detectors were used to detect the characteristic X-rays produced and the measured X-ray yields were used to calculate absolute ionization cross sections. The experimental results are compared with the predictions of the ECPSSR theory originally developed by Brandt and Lapicki. The development of the ECPSSR description of the ionization process is presented in detail and major differences between the experimental results and the theoretical calculations are discussed. For ion energies below about 0.2 MeV/a.m.u. the ECPSSR theory underpredicts the experimental results by up to a factor of four. For ion energies >1.0 MeV/a.m.u. the ECPSSR theory predicts the total L shell and L(,3) subshell ionization cross sections to within (TURN)20% or better. The ECPSSR theory also predicts the L(,1) subshell ionization cross sections to within (TURN)20% except near the node in the L(,1) subshell wave function. However, even at these higher energies, the ECPSSR results underpredict the experimental results for the L(,2) subshell by around 25%, with this discrepancy increasing markedly with decreasing projectile energy. The use of more realistic wave functions to describe the target electron states is discussed; however it is shown that the relativistic and binding corrections of the ECPSSR theory cannot be invoked to explain the observed discrepancies. Coulomb deflection effects are examined with a view to considering individual L subshell experimental Coloumb deflection factors. The

  6. Cross-flow VIV-induced fatigue damage of deepwater steel catenary riser at touch-down point

    NASA Astrophysics Data System (ADS)

    Wang, Kun-peng; Tang, Wen-yong; Xue, Hong-xiang

    2014-03-01

    A prediction model of the deepwater steel catenary riser VIV is proposed based on the forced oscillation test data, taking into account the riser-seafloor interaction for the cross-flow VIV-induced fatigue damage at touch-down point (TDP). The model will give more reasonable simulation of SCR response near TDP than the previous pinned truncation model. In the present model, the hysteretic riser-soil interaction model is simplified as the linear spring and damper to simulate the seafloor, and the damping is obtained according to the dissipative power during one periodic riser-soil interaction. In order to validate the model, the comparison with the field measurement and the results predicted by Shear 7 program of a full-scale steel catenary riser is carried out. The main induced modes, mode frequencies and response amplitude are in a good agreement. Furthermore, the parametric studies are carried out to broaden the understanding of the fatigue damage sensitivity to the upper end in-plane offset and seabed characteristics. In addition, the fatigue stress comparison at TDP between the truncation riser model and the present full riser model shows that the existence of touch-down zones is very important for the fatigue damage assessment of steel catenary riser at TDP.

  7. Proton pump inhibitors protect mice from acute systemic inflammation and induce long-term cross-tolerance

    PubMed Central

    Balza, E; Piccioli, P; Carta, S; Lavieri, R; Gattorno, M; Semino, C; Castellani, P; Rubartelli, A

    2016-01-01

    Incidence of sepsis is increasing, representing a tremendous burden for health-care systems. Death in acute sepsis is attributed to hyperinflammatory responses, but the underlying mechanisms are still unclear. We report here that proton pump inhibitors (PPIs), which block gastric acid secretion, selectively inhibited tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) secretion by Toll-like receptor (TLR)-activated human monocytes in vitro, in the absence of toxic effects. Remarkably, the oversecretion of IL-1β that represents a hallmark of monocytes from patients affected by cryopyrin-associated periodic syndrome is also blocked. Based on these propaedeutic experiments, we tested the effects of high doses of PPIs in vivo in the mouse model of endotoxic shock. Our data show that a single administration of PPI protected mice from death (60% survival versus 5% of untreated mice) and decreased TNF-α and IL-1β systemic production. PPIs were efficacious even when administered after lipopolysaccharide (LPS) injection. PPI-treated mice that survived developed a long-term cross-tolerance, becoming resistant to LPS- and zymosan-induced sepsis. In vitro, their macrophages displayed impaired TNF-α and IL-1β to different TLR ligands. PPIs also prevented sodium thioglycollate-induced peritoneal inflammation, indicating their efficacy also in a non-infectious setting independent of TLR stimulation. Lack of toxicity and therapeutic effectiveness make PPIs promising new drugs against sepsis and other severe inflammatory conditions. PMID:27441656

  8. Sodium chlorate induces DNA damage and DNA-protein cross-linking in rat intestine: A dose dependent study.

    PubMed

    Ali, Shaikh Nisar; Ansari, Fariheen Aisha; Arif, Hussain; Mahmood, Riaz

    2017-06-01

    Sodium chlorate (NaClO3) is widely used in paper and pulp industries and as a non-selective herbicide. It is also a major by-product generated upon disinfection of drinking water by chlorine dioxide. In this study, we have investigated the genotoxicity of NaClO3 on the small intestine of rats. Adult male rats were divided into 5 groups: one control and four NaClO3 treated groups. The NaClO3 treated groups were given a single acute oral dose of NaClO3 (100, 250, 500 and 750 mg/kg body weight) and sacrificed 24 h later. Administration of NaClO3 caused significant DNA damage in a dose dependent manner in the rat intestine. This was evident from the comet assay which showed DNA strand breaks and was further confirmed by agarose gel electrophoresis and release of free nucleotides. Increased DNA protein cross-linking in NaClO3 administered groups showed formation of a critical lesion which hampers activities of proteins/enzymes involved in DNA repair, transcription and replication. Thus, oral administration of NaClO3 induces DNA damage in the rat intestine, probably through chlorate induced production of reactive oxygen species. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Intranasal DNA Vaccination Induces Potent Mucosal and Systemic Immune Responses and Cross-protective Immunity Against Influenza Viruses

    PubMed Central

    Torrieri-Dramard, Lea; Lambrecht, Bénédicte; Ferreira, Helena Lage; Van den Berg, Thierry; Klatzmann, David; Bellier, Bertrand

    2011-01-01

    The induction of potent virus-specific immune responses at mucosal surfaces where virus transmission occurs is a major challenge for vaccination strategies. In the case of influenza vaccination, this has been achieved only by intranasal delivery of live-attenuated vaccines that otherwise pose safety problems. Here, we demonstrate that potent mucosal and systemic immune responses, both cellular and humoral, are induced by intranasal immunization using formulated DNA. We show that formulation with the DNA carrier polyethylenimine (PEI) improved by a 1,000-fold the efficiency of gene transfer in the respiratory track following intranasal administration of luciferase-coding DNA. Using PEI formulation, intranasal vaccination with DNA-encoding hemagglutinin (HA) from influenza A H5N1 or (H1N1)2009 viruses induced high levels of HA-specific immunoglobulin A (IgA) antibodies that were detected in bronchoalveolar lavages (BALs) and the serum. No mucosal responses could be detected after parenteral or intranasal immunization with naked-DNA. Furthermore, intranasal DNA vaccination with HA from a given H5N1 virus elicited full protection against the parental strain and partial cross-protection against a distinct highly pathogenic H5N1 strain that could be improved by adding neuraminidase (NA) DNA plasmids. Our observations warrant further investigation of intranasal DNA as an effective vaccination route. PMID:20959813

  10. Pressure-induced K-Λ crossing in monolayer WSe2

    NASA Astrophysics Data System (ADS)

    Ye, Yanxia; Dou, Xiuming; Ding, Kun; Jiang, Desheng; Yang, Fuhua; Sun, Baoquan

    2016-05-01

    The energy band structures and related room temperature exciton transitions of monolayer and bilayer tungsten diselenide (WSe2) are investigated using photoluminescence (PL) spectra under hydrostatic pressure up to 5.42 GPa. For monolayer WSe2, it is found that the conduction band Λ valley is 70 +/- 30 meV higher than the K valley at zero pressure, and the K-Λ valley crossover happens at a pressure of approximately 2.25 GPa. The PL peak of exciton related to the direct K-K interband transition in monolayer and bilayer WSe2 shows a pressure-induced blue-shift at the rates of 31.5 +/- 0.6 and 27 +/- 1 meV GPa-1, respectively. The indirect Λ-K interband transition for monolayer and bilayer WSe2 exhibits a distinctly different pressure response. The pressure coefficient is as small as -3 +/- 6 meV GPa-1 for monolayer, but a much larger value of -22 +/- 1 meV GPa-1 for bilayer WSe2, indicating that the interlayer coupling has a strong effect on the electronic states at the Λ valley.The energy band structures and related room temperature exciton transitions of monolayer and bilayer tungsten diselenide (WSe2) are investigated using photoluminescence (PL) spectra under hydrostatic pressure up to 5.42 GPa. For monolayer WSe2, it is found that the conduction band Λ valley is 70 +/- 30 meV higher than the K valley at zero pressure, and the K-Λ valley crossover happens at a pressure of approximately 2.25 GPa. The PL peak of exciton related to the direct K-K interband transition in monolayer and bilayer WSe2 shows a pressure-induced blue-shift at the rates of 31.5 +/- 0.6 and 27 +/- 1 meV GPa-1, respectively. The indirect Λ-K interband transition for monolayer and bilayer WSe2 exhibits a distinctly different pressure response. The pressure coefficient is as small as -3 +/- 6 meV GPa-1 for monolayer, but a much larger value of -22 +/- 1 meV GPa-1 for bilayer WSe2, indicating that the interlayer coupling has a strong effect on the electronic states at the Λ valley

  11. Age-Dependent Myeloid Dendritic Cell Responses Mediate Resistance to La Crosse Virus-Induced Neurological Disease

    PubMed Central

    Taylor, Katherine G.; Woods, Tyson A.; Winkler, Clayton W.; Carmody, Aaron B.

    2014-01-01

    ABSTRACT La Crosse virus (LACV) is the major cause of pediatric viral encephalitis in the United States; however, the mechanisms responsible for age-related susceptibility in the pediatric population are not well understood. Our current studies in a mouse model of LACV infection indicated that differences in myeloid dendritic cell (mDC) responses between weanling and adult mice accounted for susceptibility to LACV-induced neurological disease. We found that type I interferon (IFN) responses were significantly stronger in adult than in weanling mice. Production of these IFNs required both endosomal Toll-like receptors (TLRs) and cytoplasmic RIG-I-like receptors (RLRs). Surprisingly, IFN expression was not dependent on plasmacytoid DCs (pDCs) but rather was dependent on mDCs, which were found in greater number and induced stronger IFN responses in adults than in weanlings. Inhibition of these IFN responses in adults resulted in susceptibility to LACV-induced neurological disease, whereas postinfection treatment with type I IFN provided protection in young mice. These studies provide a definitive mechanism for age-related susceptibility to LACV encephalitis, where mDCs in young mice are insufficiently activated to control peripheral virus replication, thereby allowing virus to persist and eventually cause central nervous system (CNS) disease. IMPORTANCE La Crosse virus (LACV) is the primary cause of pediatric viral encephalitis in the United States. Although the virus infects both adults and children, over 80% of the reported neurological disease cases are in children. To understand why LACV causes neurological disease primarily in young animals, we used a mouse model where weanling mice, but not adult mice, develop neurological disease following virus infection. We found that an early immune response cell type, myeloid dendritic cells, was critical for protection in adult animals and that these cells were reduced in young animals. Activation of these cells during

  12. Wind induced resonant cross flow vibrations on Norwegian offshore flare booms

    SciTech Connect

    Oppen, A.N.; Kvitrud, A.

    1995-12-31

    Vibrations and fatigue cracking have occurred, for some years, i flare boom structures on a number of platforms on the Norwegian continental shelf. In view of this, the objective of this paper is to: (1) Describe the vibrations and its characteristics on Statfjord A and Heimdal which had the largest vibrations, the vibrations can`t be predicted by vortex induced vibrations of individual members but could be caused by wake effects, local frame vibrations or global dynamic effects. (2) Review the evaluation of cracks in other flare boom structures, the work has been based on DIN 4133 and includes vibrations of both individual members and frames. (3) Review the design practice and operational experience with design parameters especially measurements of damping on individual tubular members and observed vibrations of individual members and frames. Possible limitations of the DIN standard will be discussed. (4) A promising device for reducing the vibrations is described. The problems have mainly been caused by the methods used in design, however, evidence of welding defects initiating fatigue cracks has also been found. A review of the existing methods has led to the recommendation of using the German DIN 4133 code for design purposes. This code is to a large extent similar to the proposed Eurocode-1. A design procedure based on DIN 4133 is proposed including additional parametric boundaries for avoiding resonant vibration.

  13. Cross-generational trans fat intake exacerbates UV radiation-induced damage in rat skin.

    PubMed

    Barcelos, R C S; Vey, L T; Segat, H J; Roversi, K; Roversi, Kr; Dias, V T; Trevizol, F; Kuhn, F T; Dolci, G S; Pase, C S; Piccolo, J; Veit, J C; Emanuelli, T; Luz, S C A; Bürger, M E

    2014-07-01

    We evaluated the influence of dietary fats on ultraviolet radiation (UVR)-induced oxidative damage in skin of rats. Animals from two consecutive generations born of dams supplemented with fats during pregnancy and breastfeeding were maintained in the same supplementation: soybean-oil (SO, rich in n-6 FA, control group), fish-oil (FO, rich in n-3 FA) or hydrogenated-vegetable-fat (HVF, rich in TFA). At 90 days of age, half the animals from the 2nd generation were exposed to UVR (0.25 J/cm(2)) 3×/week for 12 weeks. The FO group presented higher incorporation of n-3 FA in dorsal skin, while the HVF group incorporated TFA. Biochemical changes per se were observed in skin of the HVF group: greater generation of reactive oxygen species (ROS), lower mitochondrial integrity and increased Na(+)K(+)-ATPase activity. UVR exposure increased skin wrinkles scores and ROS generation and decreased mitochondrial integrity and reduced-glutathione levels in the HVF group. In FO, UVR exposure was associated with smaller skin thickness and reduced levels of protein-carbonyl, together with increased catalase activity and preserved Na(+)K(+)-ATPase function. In conclusion, while FO may be protective, trans fat may be harmful to skin health by making it more vulnerable to UVR injury and thus more prone to develop photoaging and skin cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Hair loss pattern due to chemotherapy-induced anagen effluvium: a cross-sectional observation.

    PubMed

    Yun, Sook Jung; Kim, Seong-Jin

    2007-01-01

    Anagen effluvium is a common side effect of chemotherapy, but few studies have examined its clinical characteristics. This study was aimed at evaluating the hair loss caused by chemotherapeutic agents. Sixty-four patients with anagen effluvium were evaluated in the study. Chemotherapeutic agents were classified into 5 different groups. The pattern of hair loss was analyzed when specific involvement of the hairline was obvious. Forty-six (71.9%) of the 64 total patients maintained hairs along their hairline. Hairs were maintained with a total hairline in 20 (31.3%), frontal hairline in 13 (20.3%) and occipital hairline in 12 (18.8%) patients. Among the 20 males with patterned hair loss, the following hairlines were preserved: occipital in 10 (50%), total in 7 (35%) and frontal in 3 (15%). Among the 25 females with patterned hair loss, hairlines were preserved as total in 13 (52%), frontal in 10 (40%) and occipital in 2 (8%). However, no significant differences were detected in hair loss patterns according to age, associated symptoms, chemotherapeutic agent group or combination of chemotherapeutic agents. Our results suggest that anagen effluvium induced by chemotherapeutic agents represents patterned hair loss. 2007 S. Karger AG, Basel

  15. Study on factors inducing workplace violence in Chinese hospitals based on the broken window theory: a cross-sectional study.

    PubMed

    Zhou, Chenyu; Mou, Huitong; Xu, Wen; Li, Zhe; Liu, Xin; Shi, Lei; Peng, Boshi; Zhao, Yan; Gao, Lei; Fan, Lihua

    2017-07-28

    To explore the potential components of hospital workplace violence (HWPV) from the perspectives of hospital administrators and patients, and put forward corresponding strategies for its prevention and control. Using convenience sampling methods, 116 hospitals in 14 provinces of China were surveyed using a self-designed questionnaire. A cross-sectional study was used. Hospital administrators and patients from 116 hospitals in 14 provinces of China. First, hospital administrators point of workplace factors included six factors, with the following weighting coefficients: hospital administrator factors (29.40%), patient-related factors (20.08%), hospital environmental factors (19.45%), policy and institutional factors (11.92%), social psychological factors (10.26%), objective events factors (8.89%). Second, patients from the hospital workplace predisposing factors included three common factors. The weight coefficients of these were hospital-related factors (60.27%), social and governmental factors (23.64%) and patient-related factors (16.09%). A wide range of factors according to hospital administrators, patients and in the hospital environment play important roles in HWPV. From the perspectives of hospital administrators, communication skills and attitude to the service are important factors for inducing HWPV. From the perspective of patients, the characteristics of staff personalities and medical cognition are more important inducing factors. As far as social factors are concerned, economic compensation of medical malpractice is an important inducing factor for HWPV. In terms of environmental factors, management of Chinese medical hospitals, medical procedures and the layout of departments are all potential factors for the occurrence of violence. Corresponding defects were exposed in the health legal system and the supervision system for influencing public opinion. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017

  16. Role of p53-fibrinolytic system cross-talk in the regulation of quartz-induced lung injury.

    PubMed

    Bhandary, Yashodhar P; Shetty, Shwetha K; Marudamuthu, Amarnath S; Fu, Jian; Pinson, Barbara M; Levin, Jeffrey; Shetty, Sreerama

    2015-03-01

    Silica is the major component of airborne dust generated by wind, manufacturing and/or demolition. Chronic occupational inhalation of silica dust containing crystalline quartz is by far the predominant form of silicosis in humans. Silicosis is a progressive lung disease that typically arises after a very long latency and is a major occupational concern with no known effective treatment. The mechanism of silicosis is not clearly understood. However, silicosis is associated with increased cell death, expression of redox enzymes and pro-fibrotic cytokines and chemokines. Since alveolar epithelial cell (AEC) death and disruption of alveolar fibrinolysis is often associated with both acute and chronic lung injuries, we explored whether p53-mediated changes in the urokinase-type plasminogen activator (uPA) system contributes to silica-induced lung injury. We further sought to determine whether caveolin-1 scaffolding domain peptide (CSP), which inhibits p53 expression, mitigates lung injury associated with exposure to silica. Lung tissues and AECs isolated from wild-type (WT) mice exposed to silica exhibit increased apoptosis, p53 and PAI-1, and suppression of uPA expression. Treatment of WT mice with CSP inhibits PAI-1, restores uPA expression and prevents AEC apoptosis by suppressing p53, which is otherwise induced in mice exposed to silica. The process involves CSP-mediated inhibition of serine-15 phosphorylation of p53 by inhibition of protein phosphatase 2A-C (PP2A-C) interaction with silica-induced caveolin-1 in AECs. These observations suggest that changes in the p53-uPA fibrinolytic system cross-talk contribute to lung injury caused by inhalation of silica dust containing crystalline quartz and is protected by CSP by targeting this pathway.

  17. Cross-sectional study of kidney stones by laser-induced breakdown spectroscopy.

    PubMed

    Singh, V K; Rai, A K; Rai, P K; Jindal, P K

    2009-09-01

    We performed laser-induced breakdown spectroscopy (LIBS) for the in situ quantitative estimation of elemental constituents distributed in different parts of kidney stones obtained directly from patients by surgery. We did this by focusing the laser light directly on the center, shell, and surface of the stones to find the spatial distribution of the elements inside the stone. The elements detected in the stones were calcium, magnesium, manganese, copper, iron, zinc, strontium, sodium, potassium, carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, and chlorine (Cl), etc. We optimized the LIBS signals by varying the laser energy from 10 mJ to 40 mJ to obtain the best signal-to-background and signal-to-noise ratios. We estimated the quantities of different elements in the stones by drawing calibration curves, plotting graphs of the analyte signal versus the absolute concentration of the elements in standard samples. The detection limits of the calibration curves were discussed. The concentrations of the different elements were found to be widely different in different stones found in different age groups of patients. It was observed that stones containing higher amounts of copper also possessed higher amounts of zinc. In general, the concentrations of trace elements present in the kidney stones decreased as we moved from center to shell and surface. Our results also revealed that the concentrations of elements present in the stones increased with the age of the patients. The results obtained from the calibration curves were compared with results from inductively coupled plasma mass spectrometry (ICP-MS). We also used the intensity ratios of different elemental lines to find the spatial distribution of different elements inside the kidney stones.

  18. Study of several factors in RNA-protein cross-link formation induced by ionizing radiations within 70S ribosomes of E. coli MRE 600.

    PubMed

    Ekert, B; Giocanti, N; Sabattier, R

    1986-09-01

    The induction of RNA-protein crosslinks in E. coli 70S ribosomes by gamma-irradiation was studied by measuring the dependence of cross-link formation on ribosome concentration. The inverse dependence of cross-link percentage upon concentration up to at least 20 A260 nm units ml-1 indicate that indirect effects seem to play a more major part than direct effects for these ribosome concentrations. The effect of various gases and free radical scavengers was used to determine the roles of the radicals H., CO2-., OH. and e-aq and to estimate their relative efficiencies for cross-links. They were found to be: 7.2(H.), 6(CO2-.), 2(OH.) and 1(e-aq). The extent of RNA-protein cross-link production in 70S ribosomes induced by gamma-rays and neutrons in the presence and absence of oxygen was also investigated. Cross-link formation was estimated by separation of linked and unlinked material on nitrocellulose filters or after separation by SDS-sucrose gradient centrifugation under dissociating conditions. Oxygen inhibited cross-link formation by both neutrons and gamma-rays. However, very few cross-links were formed in de-aerated solutions by exposure to neutrons, compared to those produced by gamma-rays under the same conditions. This suggests that molecular oxygen generated along the secondary particle track can reduce the formation of RNA-protein cross-links.

  19. A Brief Period of Hypothermia Induced by Total Liquid Ventilation Decreases End-Organ Damage and Multiorgan Failure Induced by Aortic Cross-Clamping.

    PubMed

    Mongardon, Nicolas; Kohlhauer, Matthias; Lidouren, Fanny; Hauet, Thierry; Giraud, Sébastien; Hutin, Alice; Costes, Bruno; Barau, Caroline; Bruneval, Patrick; Micheau, Philippe; Cariou, Alain; Dhonneur, Gilles; Berdeaux, Alain; Ghaleh, Bijan; Tissier, Renaud

    2016-09-01

    In animal models, whole-body cooling reduces end-organ injury after cardiac arrest and other hypoperfusion states. The benefits of cooling in humans, however, are uncertain, possibly because detrimental effects of prolonged cooling may offset any potential benefit. Total liquid ventilation (TLV) provides both ultrafast cooling and rewarming. In previous reports, ultrafast cooling with TLV potently reduced neurological injury after experimental cardiac arrest in animals. We hypothesized that a brief period of rapid cooling and rewarming via TLV could also mitigate multiorgan failure (MOF) after ischemia-reperfusion induced by aortic cross-clamping. Anesthetized rabbits were submitted to 30 minutes of supraceliac aortic cross-clamping followed by 300 minutes of reperfusion. They were allocated either to a normothermic procedure with conventional ventilation (control group) or to hypothermic TLV (33°C) before, during, and after cross-clamping (pre-clamp, per-clamp, and post-clamp groups, respectively). In all TLV groups, hypothermia was maintained for 75 minutes and switched to a rewarming mode before resumption to conventional mechanical ventilation. End points included cardiovascular, renal, liver, and inflammatory parameters measured 300 minutes after reperfusion. In the normothermic (control) group, ischemia-reperfusion injury produced evidence of MOF including severe vasoplegia, low cardiac output, acute kidney injury, and liver failure. In the TLV group, we observed gradual improvements in cardiac output in post-clamp, per-clamp, and pre-clamp groups versus control (53 ± 8, 64 ± 12, and 90 ± 24 vs 36 ± 23 mL/min/kg after 300 minutes of reperfusion, respectively). Liver biomarker levels were also lower in pre-clamp and per-clamp groups versus control. However, acute kidney injury was prevented in pre-clamp, and to a limited extent in per-clamp groups, but not in the post-clamp group. For instance, creatinine clearance was 4.8 ± 3.1 and 0.5 ± 0.6 m

  20. Less is more: Nutrient limitation induces cross-talk of nutrient sensing pathways with NAD+ homeostasis and contributes to longevity

    PubMed Central

    TSANG, Felicia; LIN, Su-Ju

    2016-01-01

    Nutrient sensing pathways and their regulation grant cells control over their metabolism and growth in response to changing nutrients. Factors that regulate nutrient sensing can also modulate longevity. Reduced activity of nutrient sensing pathways such as glucose-sensing PKA, nitrogen-sensing TOR and S6 kinase homolog Sch9 have been linked to increased life span in the yeast, Saccharomyces cerevisiae, and higher eukaryotes. Recently, reduced activity of amino acid sensing SPS pathway was also shown to increase yeast life span. Life span extension by reduced SPS activity requires enhanced NAD+ (nicotinamide adenine dinucleotide, oxidized form) and nicotinamide riboside (NR, a NAD+ precursor) homeostasis. Maintaining adequate NAD+ pools has been shown to play key roles in life span extension, but factors regulating NAD+ metabolism and homeostasis are not completely understood. Recently, NAD+ metabolism was also linked to the phosphate (Pi)-sensing PHO pathway in yeast. Canonical PHO activation requires Pi-starvation. Interestingly, NAD+ depletion without Pi-starvation was sufficient to induce PHO activation, increasing NR production and mobilization. Moreover, SPS signaling appears to function in parallel with PHO signaling components to regulate NR/NAD+ homeostasis. These studies suggest that NAD+ metabolism is likely controlled by and/or coordinated with multiple nutrient sensing pathways. Indeed, cross-regulation of PHO, PKA, TOR and Sch9 pathways was reported to potentially affect NAD+ metabolism; though detailed mechanisms remain unclear. This review discusses yeast longevity-related nutrient sensing pathways and possible mechanisms of life span extension, regulation of NAD+ homeostasis, and cross-talk among nutrient sensing pathways and NAD+ homeostasis. PMID:27683589

  1. Cross-talk between the aryl hydrocarbon receptor and hypoxia inducible factor signaling pathways. Demonstration of competition and compensation.

    PubMed

    Chan, W K; Yao, G; Gu, Y Z; Bradfield, C A

    1999-04-23

    The aryl hydrocarbon receptor (AHR) and the alpha-class hypoxia inducible factors (HIF1alpha, HIF2alpha, and HIF3alpha) are basic helix-loop-helix PAS (bHLH-PAS) proteins that heterodimerize with ARNT. In response to 2,3,7,8-tetrachlorodibenzo-p-dioxin, the AHR. ARNT complex binds to "dioxin responsive enhancers" (DREs) and activates genes involved in the metabolism of xenobiotics, e.g. cytochrome P4501A1 (Cyp1a1). The HIF1alpha.ARNT complex binds to "hypoxia responsive enhancers" and activates the transcription of genes that regulate adaptation to low oxygen, e.g. erythropoietin (Epo). We postulated that activation of one pathway would inhibit the other due to competition for ARNT or other limiting cellular factors. Using pathway specific reporters in transient transfection assays, we observed that DRE driven transcription was markedly inhibited by hypoxia and that hypoxia responsive enhancer driven transcription was inhibited by AHR agonists. When we attempted to support this cross-talk model using endogenous loci, we observed that activation of the hypoxia pathway inhibited Cyp1a1 up-regulation, but that activation of the AHR actually enhanced the induction of Epo by hypoxia. To explain this unexpected additivity, we examined the Epo gene and found that its promoter harbors DREs immediately upstream of its transcriptional start site. These experiments outline conditions where inhibitory and additive cross-talk occur between the hypoxia and dioxin signal transduction pathways and identify Epo as an AHR-regulated gene.

  2. Different Lepidopteran Elicitors Account for Cross-Talk in Herbivory-Induced Phytohormone Signaling1[W][OA

    PubMed Central

    Diezel, Celia; von Dahl, Caroline C.; Gaquerel, Emmanuel; Baldwin, Ian T.

    2009-01-01

    Salicylic acid (SA), jasmonic acid (JA), ethylene (ET), and their interactions mediate plant responses to pathogen and herbivore attack. JA-SA and JA-ET cross-signaling are well studied, but little is known about SA-ET cross-signaling in plant-herbivore interactions. When the specialist herbivore tobacco hornworm (Manduca sexta) attacks Nicotiana attenuata, rapid and transient JA and ET bursts are elicited without significantly altering wound-induced SA levels. In contrast, attack from the generalist beet armyworm (Spodoptera exigua) results in comparatively lower JA and ET bursts, but amplified SA bursts. These phytohormone responses are mimicked when the species' larval oral secretions (OSSe and OSMs) are added to puncture wounds. Fatty acid-amino acid conjugates elicit the JA and ET bursts, but not the SA burst. OSSe had enhanced glucose oxidase activity (but not β-glucosidase activity), which was sufficient to elicit the SA burst and attenuate the JA and ET levels. It is known that SA antagonizes JA; glucose oxidase activity and associated hydrogen peroxide also antagonizes the ET burst. We examined the OSMs-elicited SA burst in plants impaired in their ability to elicit JA (antisense [as]-lox3) and ET (inverted repeat [ir]-aco) bursts and perceive ET (35s-etr1b) after fatty acid-amino acid conjugate elicitation, which revealed that both ET and JA bursts antagonize the SA burst. Treating wild-type plants with ethephone and 1-methylcyclopropane confirmed these results and demonstrated the central role of the ET burst in suppressing the OSMs-elicited SA burst. By suppressing the SA burst, the ET burst likely facilitates unfettered JA-mediated defense activation in response to herbivores that otherwise would elicit SA. PMID:19458114

  3. Cytotoxic T Cells Are the Predominant Players Providing Cross-Protective Immunity Induced by γ-Irradiated Influenza A Viruses ▿

    PubMed Central

    Furuya, Yoichi; Chan, Jennifer; Regner, Matthias; Lobigs, Mario; Koskinen, Aulikki; Kok, Tuckweng; Manavis, Jim; Li, Peng; Müllbacher, Arno; Alsharifi, Mohammed

    2010-01-01

    We previously demonstrated that a single dose of nonadjuvanted intranasal γ-irradiated influenza A virus can provide robust protection in mice against both homologous and heterosubtypic challenges, including challenge with an H5N1 avian virus strain. We investigated the mechanism behind the observed cross-protection to define which arms of the adaptive immune response are involved in mediating this protection. Studies with gene knockout mice showed the cross-protective immunity to be mediated mainly by T cells and to be dependent on the cytolytic effector molecule perforin. Adoptive transfer of memory T cells from immunized mice, but not of memory B cells, protected naïve recipients against lethal heterosubtypic influenza virus challenge. Furthermore, γ-irradiated influenza viruses induced cross-reactive Tc-cell responses but not cross-neutralizing or cross-protective antibodies. In addition, histological analysis showed reduced lung inflammation in vaccinated mice compared to that in unvaccinated controls following heterosubtypic challenge. This reduced inflammation was associated with enhanced early recruitment of T cells, both CD4+ and CD8+, and with early influenza virus-specific cytotoxic T-cell responses. Therefore, cross-protective immunity induced by vaccination with γ-irradiated influenza A virus is mediated mainly by Tc-cell responses. PMID:20164231

  4. Momentum transport cross-section measurements for potassium and rubidium in rare gases and white light-induced separation of rubidium isotopes

    SciTech Connect

    Mugglin, D.T.

    1993-12-31

    This dissertation is concerned with two light-induced kinetic effects, light-induced diffusive pulling and light-induced drift. We use a light-induced diffusive pulling experiment to measure the ground state velocity-changing collision cross section (related to the momentum transport cross section and the diffusion coefficient) and the relative difference ({Delta}{sigma}/{sigma}) of the excited and ground state cross sections with respect to that of the ground state for potassium mixed with inert buffer gases. The measured excited state cross section is a weighted average of the potassium 4{sup 2}P{sub 1/2} and 4{sup 2}P{sub 3/2} fine structure levels, which are mixed by collisions with inert gas atoms. For the ground state cross sections, we obtain the following experimental results for potassium mixed with He, Ne, Ar, Kr, and Xe, respectively: 52 {+-} 4, 57 {+-} 8, 61 {+-} 5, 43 {+-} 5, and 60 {+-}5 {angstrom}{sup 2}. For {Delta}{sigma}/{sigma}, we obtain the following (in the same order): 0.085 {+-} 0.010, 0.058 {+-} 0.006, 0.41 {+-} 0.03, 0.43 {+-} 0.03, and 0.61 {+-} 0.05. For potassium-Ne and potassium-Ar, we combine these measurements with light-induced drift measurements of the ratio {Delta}{sigma}(J = 3/2) : {Delta}{sigma}(J = 1/2) to obtain absolute transport cross sections for the individual 4{sup 2}S{sub 1/2}, 4{sup 2}P{sub 1/2}, and 4{sup 2}P{sub 3/2} levels. We also use the light-induced diffusive pulling experimental method to measure {Delta}{sigma}/{sigma} for Rb-inert gas mixtures. We obtain values for the ground state diffusion cross section for Rb in several of the inert gases as well. We report the first experimental observation of the separation of two isotopes using broadband light by the process of white light-induced drift. For a light source, we use a broadband laser with an acousto-optic modulator as an output coupler. We verify the separation of the {sup 85}Rb and {sup 87}Rb isotopes.

  5. Cannabidiol induces programmed cell death in breast cancer cells by coordinating the cross-talk between apoptosis and autophagy.

    PubMed

    Shrivastava, Ashutosh; Kuzontkoski, Paula M; Groopman, Jerome E; Prasad, Anil

    2011-07-01

    Cannabidiol (CBD), a major nonpsychoactive constituent of cannabis, is considered an antineoplastic agent on the basis of its in vitro and in vivo activity against tumor cells. However, the exact molecular mechanism through which CBD mediates this activity is yet to be elucidated. Here, we have shown CBD-induced cell death of breast cancer cells, independent of cannabinoid and vallinoid receptor activation. Electron microscopy revealed morphologies consistent with the coexistence of autophagy and apoptosis. Western blot analysis confirmed these findings. We showed that CBD induces endoplasmic reticulum stress and, subsequently, inhibits AKT and mTOR signaling as shown by decreased levels of phosphorylated mTOR and 4EBP1, and cyclin D1. Analyzing further the cross-talk between the autophagic and apoptotic signaling pathways, we found that beclin1 plays a central role in the induction of CBD-mediated apoptosis in MDA-MB-231 breast cancer cells. Although CBD enhances the interaction between beclin1 and Vps34, it inhibits the association between beclin1 and Bcl-2. In addition, we showed that CBD reduces mitochondrial membrane potential, triggers the translocation of BID to the mitochondria, the release of cytochrome c to the cytosol, and, ultimately, the activation of the intrinsic apoptotic pathway in breast cancer cells. CBD increased the generation of reactive oxygen species (ROS), and ROS inhibition blocked the induction of apoptosis and autophagy. Our study revealed an intricate interplay between apoptosis and autophagy in CBD-treated breast cancer cells and highlighted the value of continued investigation into the potential use of CBD as an antineoplastic agent. © 2011 American Association for Cancer Research.

  6. Microbiologic, Pharmacokinetic, and Clinical Effects of Corneal Collagen Cross-Linking on Experimentally Induced Pseudomonas Keratitis in Rabbits.

    PubMed

    Cosar, C Banu; Kucuk, Mutlu; Celik, Ekrem; Gonen, Tansu; Akyar, Isin; Serteser, Mustafa; Tokat, Fatma; Ince, Umit

    2015-10-01

    To determine the effects of corneal collagen cross-linking (CXL) on the penetration of topical 0.5% moxifloxacin, on the number of colony-forming units (CFUs) in the cornea, and on the clinical course in a rabbit eye model of experimentally induced Pseudomonas aeruginosa keratitis. In this prospective animal study, experimental Pseudomonas corneal ulcers were induced in 56 corneas of 28 albino New Zealand rabbits. The corneas were randomly divided into the following 4 groups: the control group (14 eyes), the MOX group (moxifloxacin) (14 eyes), the MOX + CXL group (14 eyes), and the CXL group (14 eyes). On day 4 of the experiment, the eyes in the control group were enucleated and CFU counting was performed. On day 10 of the experiment, all eyes were enucleated and CFU counting was performed. In the MOX and MOX + CXL groups, the moxifloxacin level in the cornea, aqueous humor, iris, plasma, and serum was measured by reverse-phase high-performance liquid chromatography. The difference in the corneal CFU count between the MOX group and the MOX + CXL group was not significant (P = 0.317). Clinical improvement was greatest in the MOX + CXL group (P < 0.001). The mean corneal moxifloxacin level was 0.391 ± 0.09 μg·mg in the MOX group versus 0.291 ± 0.09 μg·mg in the MOX + CXL group; as such, CXL did not have a significant effect on antibiotic penetrance (P = 0.386). Clinical improvement was greatest in the MOX + CXL group. The synergistic effect of CXL on corneal ulcer treatment is not through antibiotic penetrance.

  7. Production cross sections of niobium and tantalum isotopes in proton-induced reactions on (nat)Zr and (nat)Hf up to 14 MeV.

    PubMed

    Murakami, M; Haba, H; Goto, S; Kanaya, J; Kudo, H

    2014-08-01

    Production cross sections of Nb and Ta isotopes in the proton-induced reactions on (nat)Zr and (nat)Hf, respectively, were measured up to 14 MeV using a stacked-foil technique. The observed nuclides in the (nat)Zr(p,x) reactions were (90g,91m,92m,95m,95g,96)Nb, (95)Zr, and (87g,88)Y. In the (nat)Hf(p,x) reactions, (175,176,177,178,179)Ta and (175)Hf were observed. The obtained cross sections for each nuclide were compared with the previously reported data and with the theoretical cross sections calculated by the TALYS-1.4 code. Thick-target yields of the observed nuclides were deduced from the measured production cross sections. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Origin of ferromagnetism and oxygen-vacancy ordering induced cross-controlled magnetoelectric effects at room temperature

    NASA Astrophysics Data System (ADS)

    Wei, X. K.; Zou, T.; Wang, F.; Zhang, Q. H.; Sun, Y.; Gu, L.; Hirata, A.; Chen, M. W.; Yao, Y.; Jin, C. Q.; Yu, R. C.

    2012-04-01

    In dilute magnetic oxide hexagonal Ba(Ti0.9Fe0.1)O2.81 bulk ceramic, we report on combined ferromagnetism and improper ferroelectricity as well as cross-controlled magnetoelectric effects at room temperature. The annular-bright-field (ABF) imaging technique in scanning transmission electron microscopy (STEM) demonstrates an oxygen vacancy ordering in the hexagonal closest-packed Ba1-O1 layers and severe distortion of the octahedra and pyramids. Strong dependencies of the susceptibility on temperature and magnetic field as well as the frequency dependence of magnetization under an ac electric field reveal that the intrinsic ferromagnetism of the highly insulating system dynamically evolves from a paramagnetic ground state, and dynamic exchanges of trapped electrons in the ordered polarons are attributed to the ferromagnetic interaction. Accordingly, aided by the motion of oxygen vacancies, responses of the trapped electrons to the ac magnetic field result in the reversal of magnetically induced voltages between high and low states. Our results not only expand our understanding on the magnetoelectric coupling mechanism, but also provide a grand opportunity toward designing novel multiferroic materials through introducing ordered point defects into a centrosymmetric matrix.

  9. Damage cross-sections for MeV energy He ion induced hydrogen ejection in polymers-material structure effects

    NASA Astrophysics Data System (ADS)

    Salah, H.; Touchrift, B.

    2004-03-01

    Using the elastic recoil detection analysis (ERDA) method for hydrogen analysis, a He-4(+) ion beam was used simultaneously for irradiating samples and as a tool to measure the hydrogen desorption yield as a function of irradiation dose. The influence of molecular structure on helium-induced desorption is studied for different polymers. The dose-response curves of hydrogen released from irradiated structures are presented and used to determine the damage cross-sections. The deduced desorption extent for a single impact is of the order of a few Angstroms, revealing localized regions of desorption. Hydrogen desorption is found to be sensitive to chemical composition of the target. The overall experimental data of the hydrogen desorption yield are described by the same function of the type Y(phi) = (C/phi(n) ) exp (-sigma phi) where phi is the irradiation dose and C and n are a fitting parameter. The first part of the function describes 'prompt ejection', predominant at lower irradiation dose where the created latent tracks remain separated. The exponential term accounts for the 'thermal ejection' process activated by ion-track overlapping involved at higher irradiation doses. A threshold dose is found that separates the two regimes and above which the overlapping tracks form a highly heated condensed gas and activate chemical processes. Chemical modifications have been studied using infrared-absorption spectroscopy, which reveal the formation of stable molecules that could desorb intact.

  10. Leishmania infantum sterol 24-c-methyltransferase formulated with MPL-SE induces cross-protection against L. major infection

    PubMed Central

    Goto, Yasuyuki; Bhatia, Ajay; Raman, Vanitha S.; Vidal, Silvia E. Z.; Bertholet, Sylvie; Coler, Rhea N.; Howard, Randall F.; Reed, Steven G.

    2009-01-01

    The enzyme sterol 24-c-methyltranferase (SMT) is required for the biosynthesis of ergosterol, the major membrane sterol in Leishmania parasites. SMT and ergosterol are not found in mammals, so this protein may be an attractive target for anti-leishmanial vaccines and drugs. We have previously demonstrated that SMT from L. infantum, which causes visceral leishmaniasis, is a protective antigen against this parasite. Because this protein is highly conserved among Leishmania species, we evaluated the potential of SMT to cross-protect against a different form of leishmaniasis. Here, we show that immunization with L. infantum SMT, formulated with monophosphoryl lipid A in stable emulsion (MPL-SE), protects mice from cutaneous leishmaniasis caused by L. major. In BALB/c mice the vaccine preparation induced antigen-specific multifunctional CD4+ T cells capable of producing IFN-γ, IL-2, and/or TNF-α upon antigen re-exposure, and MPL-SE was indispensable to direct immune responses to SMT towards Th1. Mice immunized with the SMT/MPL-SE vaccine developed significantly smaller lesions following ear challenge with L. major. These results suggest that SMT is a promising vaccine antigen for multiple forms of leishmaniasis. PMID:19428898

  11. Leishmania infantum sterol 24-c-methyltransferase formulated with MPL-SE induces cross-protection against L. major infection.

    PubMed

    Goto, Yasuyuki; Bhatia, Ajay; Raman, Vanitha S; Vidal, Silvia E Z; Bertholet, Sylvie; Coler, Rhea N; Howard, Randall F; Reed, Steven G

    2009-05-11

    The enzyme sterol 24-c-methyltranferase (SMT) is required for the biosynthesis of ergosterol, the major membrane sterol in Leishmania parasites. SMT and ergosterol are not found in mammals, so this protein may be an attractive target for anti-leishmanial vaccines and drugs. We have previously demonstrated that SMT from L. infantum, which causes visceral leishmaniasis, is a protective antigen against this parasite. Because this protein is highly conserved among Leishmania species, we evaluated the potential of SMT to cross-protect against a different form of leishmaniasis. Here, we show that immunization with L. infantum SMT, formulated with monophosphoryl lipid A in stable emulsion (MPL-SE), protects mice from cutaneous leishmaniasis caused by L. major. In BALB/c mice the vaccine preparation induced antigen-specific multi-functional CD4(+) T cells capable of producing IFN-gamma, IL-2, and/or TNF-alpha upon antigen re-exposure, and MPL-SE was indispensable to direct immune responses to SMT towards Th1. Mice immunized with the SMT/MPL-SE vaccine developed significantly smaller lesions following ear challenge with L. major. These results suggest that SMT is a promising vaccine antigen for multiple forms of leishmaniasis.

  12. Bovine herpesvirus type 1 marker vaccine induces cross-protection against bubaline herpesvirus type 1 in water buffalo.

    PubMed

    Montagnaro, Serena; De Martinis, Claudio; Iovane, Valentina; Ciarcia, Roberto; Damiano, Sara; Nizza, Sandra; De Martino, Luisa; Iovane, Giuseppe; Pagnini, Ugo

    2014-09-01

    Water buffalo (Bubalus bubalis) are susceptible to bovine herpesvirus type 1 (BoHV-1) and a species-specific herpesvirus, bubaline herpesvirus type 1 (BuHV-1). In this study, an attenuated marker BoHV-1 based vaccine against BuHV-1 challenge was evaluated to determine whether it induces protection from viral replication. One group of water buffalo calves was immunized with an attenuated BoHV-1 marker vaccine. A second group was not vaccinated and used as the control. During the post-vaccination period, we monitored the humoral immune response. The efficacy of the vaccine was tested after intranasal challenge of the calves with a BuHV-1 strain. The experiment showed that after vaccination, BuHV-1 replication was significantly reduced by approximately three titer points compared to the controls. The control animals showed high levels of viral shedding and mild signs associated with BuHV-1 infection. Therefore, our study provides evidence for the existence of cross-protection between BoHV-1 and BuHV-1 in buffalo calves.

  13. Elevated ultraviolet-B radiation induces cross-protection to cold in leaves of Rhododendron under field conditions.

    PubMed

    Chalker-Scott, Linda; Scott, James D

    2004-02-01

    Previously, we have shown a cold-hardening response in Rhododendron 'English Roseum' exposed to elevated ultraviolet-B radiation (UV-B, 280-320 nm) under growth chamber conditions. We have conducted the present study under field conditions to provide for a higher ratio of photosynthetically active radiation to UV-B (PAR:UV-B) than is possible in the laboratory and to more accurately reflect natural conditions of solar irradiance. Leaf disks taken after 3 months from UV-B-exposed plants exhibited a greater tolerance to freezing temperatures than those from control plants that received no supplemental UV-B exposure during this time. Leaf disks taken from UV-B-irradiated plants survived temperatures below -8 degrees C, whereas control disks were killed at -6 degrees C. Cold hardiness did not significantly increase until September, when environmental cues such as decreasing day length and night temperatures also may have enhanced hardening. Our field findings confirm our previous laboratory study, demonstrating that elevated UV-B induces cross-protection to cold in Rhododendron leaf tissues.

  14. Cross-talk between TLR4 and PPARγ pathways in the arachidonic acid-induced inflammatory response in pancreatic acini.

    PubMed

    Mateu, A; Ramudo, L; Manso, M A; De Dios, I

    2015-12-01

    Arachidonic acid (AA) is generally associated with inflammation in different settings. We assess the molecular mechanisms involved in the inflammatory response exerted by AA on pancreatic acini as an approach to acute pancreatitis (AP). Celecoxib (COX-2 inhibitor), TAK-242 (TLR4 inhibitor) and 15d-PGJ2 (PPARγ agonist) were used to ascertain the signaling pathways. In addition, we examine the effects of TAK-242 and 15d-PGJ2 on AP induced in rats by bile-pancreatic duct obstruction (BPDO). To carry out in vitro studies, acini were isolated from pancreas of control rats. Generation of PGE2 and TXB2, activation of pro-inflammatory pathways (MAPKs, NF-κB, and JAK/STAT3) and overexpression of CCL2 and P-selectin was found in AA-treated acini. In addition, AA up-regulated TLR4 and down-regulated PPARγ expression. Celecoxib prevented the up-regulation of CCL2 and P-selectin but did not show any effect on the AA-mediated changes in TLR4 and PPARγ expression. TAK-242, reduced the generation of AA metabolites and repressed both the cascade of pro-inflammatory events which led to CCL2 and P-selectin overexpression as well as the AA-induced PPARγ down-regulation. Thus, TLR4 acts as upstream activating pro-inflammatory and inhibiting anti-inflammatory pathways. 15d-PGJ2 down-regulated TLR4 expression and hence prevented the synthesis of AA metabolites and the inflammatory response mediated by them. Reciprocal negative cross-talk between TLR4 and PPARγ pathways is evidenced. In vivo experiments showed that TAK-242 and 15d-PGJ2 treatments reduced the inflammatory response in BPDO-induced AP. We conclude that through TLR4-dependent mechanisms, AA up-regulated CCL2 and P-selectin in pancreatic acini, partly mediated by the generation of PGE2 and TXB2, which activated pro-inflammatory pathways, but also directly by down-regulating PPARγ expression with anti-inflammatory activity. In vitro and in vivo studies support the role of TLR4 in AP and the use of TLR4 inhibitors and

  15. Vitamin E-diffused highly cross-linked UHMWPE particles induce less osteolysis compared to highly cross-linked virgin UHMWPE particles in vivo.

    PubMed

    Bichara, David A; Malchau, Erik; Sillesen, Nanna H; Cakmak, Selami; Nielsen, G Petur; Muratoglu, Orhun K

    2014-09-01

    Recent in vitro findings suggest that UHMWPE wear particles containing vitamin E (VE) may have reduced biologic activity and decreased osteolytic potential. We hypothesized that particles from VE-stabilized, radiation cross-linked UHMWPE would cause less osteolysis in a murine calvarial bone model when compared to virgin gamma irradiated cross-linked UHMWPE. Groups received equal amount of particulate debris overlaying the calvarium for 10 days. Calvarial bone was examined using high resolution micro-CT and histomorphometric analyses. There was a statistically significant difference between virgin (12.2%±8%) and VE-UHMWPE (3%±1.4%) groups in regards to bone resorption (P=0.005) and inflammatory fibrous tissue overlaying the calvaria (0.48 vs. 0.20, P<0.0001). These results suggest that VE-UHMWPE particles have reduced osteolytic potential in vivo when compared to virgin UHMWPE.

  16. Kinetic and HPV infection effects on cross-type neutralizing antibody and avidity responses induced by Cervarix®

    PubMed Central

    Kemp, Troy J.; Safaeian, Mahboobeh; Hildesheim, Allan; Pan, Yuanji; Penrose, Kerri J.; Porras, Carolina; Schiller, John T.; Lowy, Douglas R.; Herrero, Rolando; Pinto, Ligia A.

    2012-01-01

    Background We previously demonstrated that Cervarix® elicits antibody responses against vaccine-related types for which clinical efficacy was demonstrated (HPV-31 and -45). Here, we evaluated the kinetics of neutralization titers and avidity of Cervarix®-induced antibodies up to 36 months of follow-up in unexposed and HPV infected women. Methods A subset of women who participated in the Cost Rica HPV-16/18 Vaccine Trial had pre- and post-vaccination sera tested for antibody responses to HPV-16, -18, -31, -45, and -58 using a pseudovirion-based neutralization assay, and HPV-16 antibody avidity using an HPV-16 L1 VLP (virus-like particle)-based ELISA developed in our laboratory. Results In uninfected women, neutralizing antibody titers did not reach significance until after the 3rd dose for HPV-31 (month 12, p=0.009) and HPV-45 (month 12, p=0.003), but then persisted up to month 36 (HPV-31, p=0.01; HPV-45, p=0.002). Individuals infected with HPV-16 or HPV-31 at enrollment developed a significantly higher median antibody response to the corresponding HPV type after one dose, but there was not a difference between median titers after three doses compared to the HPV negative group. Median HPV-16 antibody avidity and titer increased over time up to month 12; however, the HPV-16 avidity did not correlate well with HPV-16 neutralizing antibody titers at each time point examined, except for month 6. The median avidity levels were higher in HPV-16 infected women at month 1 (p=0.04) and lower in HPV-16 infected women at month 12 (p=0.006) compared to the HPV negative women. Conclusions The persistence of cross-neutralization titers at month 36 suggests cross-reactive antibody responses are likely to persist long-term and are not influenced by infection status at enrollment. However, the weak correlation between avidity and neutralization titers emphasizes the need for examining avidity in efficacy studies to determine if high avidity antibodies play a critical role in

  17. Broadening the Heterologous Cross-Neutralizing Antibody Inducing Ability of Porcine Reproductive and Respiratory Syndrome Virus by Breeding the GP4 or M genes

    PubMed Central

    Zhou, Lei; Ni, Yan-Yan; Piñeyro, Pablo; Cossaboom, Caitlin M.; Subramaniam, Sakthivel; Sanford, Brenton J.; Dryman, Barbara A.; Huang, Yao-Wei; Meng, Xiang-Jin

    2013-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important swine pathogens, which causes reproductive failure in sows and respiratory disease in piglets. A major hurdle to control PRRSV is the ineffectiveness of the current vaccines to confer protection against heterologous strains. Since both GP4 and M genes of PRRSV induce neutralizing antibodies, in this study we molecularly bred PRRSV through DNA shuffling of the GP4 and M genes, separately, from six genetically different strains of PRRSV in an attempt to identify chimeras with improved heterologous cross-neutralizing capability. The shuffled GP4 and M genes libraries were each cloned into the backbone of PRRSV strain VR2385 infectious clone pIR-VR2385-CA. Three GP4-shuffled chimeras and five M-shuffled chimeras, each representing sequences from all six parental strains, were selected and further characterized in vitro and in pigs. These eight chimeric viruses showed similar levels of replication with their backbone strain VR2385 both in vitro and in vivo, indicating that the DNA shuffling of GP4 and M genes did not significantly impair the replication ability of these chimeras. Cross-neutralization test revealed that the GP4-shuffled chimera GP4TS14 induced significantly higher cross-neutralizing antibodies against heterologous strains FL-12 and NADC20, and similarly that the M-shuffled chimera MTS57 also induced significantly higher levels of cross-neutralizing antibodies against heterologous strains MN184B and NADC20, when compared with their backbone parental strain VR2385 in infected pigs. The results suggest that DNA shuffling of the GP4 or M genes from different parental viruses can broaden the cross-neutralizing antibody-inducing ability of the chimeric viruses against heterologous PRRSV strains. The study has important implications for future development of a broadly protective vaccine against PRRSV. PMID:23826108

  18. Broadening the heterologous cross-neutralizing antibody inducing ability of porcine reproductive and respiratory syndrome virus by breeding the GP4 or M genes.

    PubMed

    Zhou, Lei; Ni, Yan-Yan; Piñeyro, Pablo; Cossaboom, Caitlin M; Subramaniam, Sakthivel; Sanford, Brenton J; Dryman, Barbara A; Huang, Yao-Wei; Meng, Xiang-Jin

    2013-01-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important swine pathogens, which causes reproductive failure in sows and respiratory disease in piglets. A major hurdle to control PRRSV is the ineffectiveness of the current vaccines to confer protection against heterologous strains. Since both GP4 and M genes of PRRSV induce neutralizing antibodies, in this study we molecularly bred PRRSV through DNA shuffling of the GP4 and M genes, separately, from six genetically different strains of PRRSV in an attempt to identify chimeras with improved heterologous cross-neutralizing capability. The shuffled GP4 and M genes libraries were each cloned into the backbone of PRRSV strain VR2385 infectious clone pIR-VR2385-CA. Three GP4-shuffled chimeras and five M-shuffled chimeras, each representing sequences from all six parental strains, were selected and further characterized in vitro and in pigs. These eight chimeric viruses showed similar levels of replication with their backbone strain VR2385 both in vitro and in vivo, indicating that the DNA shuffling of GP4 and M genes did not significantly impair the replication ability of these chimeras. Cross-neutralization test revealed that the GP4-shuffled chimera GP4TS14 induced significantly higher cross-neutralizing antibodies against heterologous strains FL-12 and NADC20, and similarly that the M-shuffled chimera MTS57 also induced significantly higher levels of cross-neutralizing antibodies against heterologous strains MN184B and NADC20, when compared with their backbone parental strain VR2385 in infected pigs. The results suggest that DNA shuffling of the GP4 or M genes from different parental viruses can broaden the cross-neutralizing antibody-inducing ability of the chimeric viruses against heterologous PRRSV strains. The study has important implications for future development of a broadly protective vaccine against PRRSV.

  19. The cross sections and energy spectra of the particle emission in proton induced reaction on 204,206,207,208Pb and 209Bi

    NASA Astrophysics Data System (ADS)

    Zhang, Zhengjun; Liang, Haiying; Xu, Yongli; Han, Yinlu; Cai, Chonghai; Shen, Qingbiao

    2017-09-01

    All cross sections of proton induced reactions, angular distributions, energy spectra and double differential cross sections of neutron, proton, deuteron, triton, helium and alpha-particle emissions for p+ 204,206,207,208Pb, 209Bi reactions are consistently calculated and analyzed at incident proton energies below 200 MeV. The optical model, the distorted wave Born approximation theory, the unified Hauser-Feshbach and exciton model which includes the improved Iwamoto-Harada model are used. Theoretically calculated results are compared with the existing experimental data.

  20. Analysis of nucleon-induced fission cross sections of lead and bismuth at energies from 45 to 500 MeV

    SciTech Connect

    Prokofyev, A.V.; Mashnik, S.G.; Sierk, A.J.

    1998-08-01

    In order to investigate the applicability of the Cascade-Exciton model (CEM) of nuclear reactions to fission cross sections and hoping to learn more about intermediate-energy fission, the authors use an extended version of the CEM, as realized in the code CEM95 to perform a detailed analysis of proton- and neutron-induced fission cross sections of {sup 209}Bi and {sup 208}Pb nuclei and of the linear momentum transfer to the fissioning nuclei in the 45--500 meV energy range.

  1. Understanding of the viscoelastic response of the human corneal stroma induced by riboflavin/UV-a cross-linking at the nano level.

    PubMed

    Labate, Cristina; De Santo, Maria Penelope; Lombardo, Giuseppe; Lombardo, Marco

    2015-01-01

    To investigate the viscoelastic changes of the human cornea induced by riboflavin/UV-A cross-linking using Atomic Force Microscopy (AFM) at the nano level. Seven eye bank donor corneas were investigated, after gently removing the epithelium, using a commercial AFM in the force spectroscopy mode. Silicon cantilevers with tip radius of 10 nm and spring elastic constants between 26- and 86-N/m were used to probe the viscoelastic properties of the anterior stroma up to 3 µm indentation depth. Five specimens were tested before and after riboflavin/UV-A cross-linking; the other two specimens were chemically cross-linked using glutaraldehyde 2.5% solution and used as controls. The Young's modulus (E) and the hysteresis (H) of the corneal stroma were quantified as a function of the application load and scan rate. The Young's modulus increased by a mean of 1.1-1.5 times after riboflavin/UV-A cross-linking (P<0.05). A higher increase of E, by a mean of 1.5-2.6 times, was found in chemically cross-linked specimens using glutaraldehyde 2.5% (P<0.05). The hysteresis decreased, by a mean of 0.9-1.5 times, in all specimens after riboflavin/UV-A cross-linking (P<0.05). A substantial decrease of H, ranging between 2.6 and 3.5 times with respect to baseline values, was observed in glutaraldehyde-treated corneas (P<0.05). The present study provides the first evidence that riboflavin/UV-A cross-linking induces changes of the viscoelastic properties of the cornea at the scale of stromal molecular interactions.

  2. Understanding of the Viscoelastic Response of the Human Corneal Stroma Induced by Riboflavin/UV-A Cross-Linking at the Nano Level

    PubMed Central

    Labate, Cristina; De Santo, Maria Penelope; Lombardo, Giuseppe; Lombardo, Marco

    2015-01-01

    Purpose To investigate the viscoelastic changes of the human cornea induced by riboflavin/UV-A cross-linking using Atomic Force Microscopy (AFM) at the nano level. Methods Seven eye bank donor corneas were investigated, after gently removing the epithelium, using a commercial AFM in the force spectroscopy mode. Silicon cantilevers with tip radius of 10 nm and spring elastic constants between 26- and 86-N/m were used to probe the viscoelastic properties of the anterior stroma up to 3 µm indentation depth. Five specimens were tested before and after riboflavin/UV-A cross-linking; the other two specimens were chemically cross-linked using glutaraldehyde 2.5% solution and used as controls. The Young’s modulus (E) and the hysteresis (H) of the corneal stroma were quantified as a function of the application load and scan rate. Results The Young’s modulus increased by a mean of 1.1-1.5 times after riboflavin/UV-A cross-linking (P<0.05). A higher increase of E, by a mean of 1.5-2.6 times, was found in chemically cross-linked specimens using glutaraldehyde 2.5% (P<0.05). The hysteresis decreased, by a mean of 0.9-1.5 times, in all specimens after riboflavin/UV-A cross-linking (P<0.05). A substantial decrease of H, ranging between 2.6 and 3.5 times with respect to baseline values, was observed in glutaraldehyde-treated corneas (P<0.05). Conclusions The present study provides the first evidence that riboflavin/UV-A cross-linking induces changes of the viscoelastic properties of the cornea at the scale of stromal molecular interactions. PMID:25830534

  3. Convective heat transfer on a flat surface induced by a vertically-oriented piezoelectric fan in the presence of cross flow

    NASA Astrophysics Data System (ADS)

    Li, Xin-Jun; Zhang, Jing-zhou; Tan, Xiao-ming

    2017-09-01

    Experimental tests are carried out to investigate the convective heat transfer performances on a flat surface around the vibration envelope of a vertically-oriented piezoelectric fan in the presence of cross flow. Distinct behaviors of convective heat transfer are illustrated under the present conditions of piezoelectric-fan excitation voltage ( U = 50, 150, 250 V) or characteristic velocity ( u PF = 0.83, 1.67, 2.34 m/s) fan tip-to-heated surface gap ( G = 3, 5, 7 mm) and cross flow velocity ( u CH = 0.94, 1.56 m/s). In addition, three-dimensional flow field simulations are conducted to illustrate the instantaneous flow fields around the vibrating fan. By comparing with the pure piezoelectric fan, the vortex induced by the vibrating fan is pushed downward by the cross flow and a series of vortices are displayed down the vibrating fan. It is confirmed that the presence of cross flow is contributive to the improvement of convective heat transfer in the rear zone downstream fan vibration envelope. The impingement role of streaming flow induced by piezoelectric fan is reduced by the presence of cross flow in the fan vibration envelope. On the other hand, the oscillating movement of the piezoelectric fan promotes the disturbance intensity of cross flow passing through the fan vibration envelope. These two aspects make the conjugated convective heat transfer in the vicinity of fan vibration envelope complicated. In general, the convective heat transfer in the vicinity of fan vibration envelope is mostly improved by the combined action of fan-excited steaming flow and cross flow in the situation where the piezoelectric fan is placed very close to the heated surface.

  4. Effect of inactivation method on the cross-protective immunity induced by whole 'killed' influenza A viruses and commercial vaccine preparations.

    PubMed

    Furuya, Yoichi; Regner, Matthias; Lobigs, Mario; Koskinen, Aulikki; Müllbacher, Arno; Alsharifi, Mohammed

    2010-06-01

    We have recently shown that intranasal (i.n.) administration of gamma-irradiated A/PR/8 [A/Puerto Rico/8/34 (H1N1)] protects mice against lethal avian influenza A/Vietnam/1203/2004 (H5N1) and other heterosubtypic influenza A infections. Here, we used gamma-irradiated, formalin- and UV-inactivated A/PC [A/Port Chalmers/1/73 (H3N2)] virus preparations and compared their ability to induce both homologous and heterosubtypic protective immunity. Our data show that, in contrast to i.n. vaccination with formalin- or UV-inactivated virus, or the present commercially available trivalent influenza vaccine, a single dose of gamma-ray-inactivated A/PC (gamma-A/PC) conferred significant protection in mice against both homologous and heterosubtypic virus challenges. A multiple immunization regime was required for formalin-inactivated virus preparations to induce protective immunity against a homotypic virus challenge, but did not induce influenza A strain cross-protective immunity. The highly immunogenic gamma-A/PC, but not formalin- or UV-inactivated A/PC, nor the currently available subvirion vaccine, elicited cytotoxic T-cell responses that are most likely responsible for the cross-protective and long-lasting immunity against highly lethal influenza A infections in mice. Finally, freeze-drying of gamma-A/PC did not affect the ability to induce cross-protective immunity.

  5. Water-Responsive Shape Recovery Induced Buckling in Biodegradable Photo-Cross-Linked Poly(ethylene glycol) (PEG) Hydrogel.

    PubMed

    Salvekar, Abhijit Vijay; Huang, Wei Min; Xiao, Rui; Wong, Yee Shan; Venkatraman, Subbu S; Tay, Kiang Hiong; Shen, Ze Xiang

    2017-02-21

    -responsive shape memory embolization plug for temporary vascular occlusion. The plug consists of a composite with a poly(dl-lactide-co-glycolide) (PLGA) core (loaded with radiopaque filler) and cross-linked poly(ethylene glycol) (PEG) hydrogel outer layer. The device can be activated by body fluid (or water) after about 2 min of immersion in water. The whole occlusion process is completed within a few dozens of seconds. The underlying mechanism is water-responsive shape recovery induced buckling, which occurs in an expeditious manner within a short time period and does not require complete hydration of the whole hydrogel. In this paper, we experimentally and analytically investigate the water-activated shape recovery induced buckling in this biodegradable PEG hydrogel to understand the fundamentals in precisely controlling the buckling time. The molecular mechanism responsible for the water-induced SME in PEG hydrogel is also elucidated. The original diameter and amount of prestretching are identified as two influential parameters to tailor the buckling time between 1 and 4 min as confirmed by both experiments and simulation. The phenomenon reported here, chemically induced buckling via a combination of the SME and swelling, is generic, and the study reported here should be applicable to other water- and non-water-responsive gels.

  6. Fragmentation behavior of a thiourea-based reagent for protein structure analysis by collision-induced dissociative chemical cross-linking.

    PubMed

    Müller, Mathias Q; Dreiocker, Frank; Ihling, Christian H; Schäfer, Mathias; Sinz, Andrea

    2010-08-01

    The fragmentation behavior of a novel thiourea-based cross-linker molecule specifically designed for collision-induced dissociation (CID) MS/MS experiments is described. The development of this cross-linker is part of our ongoing efforts to synthesize novel reagents, which create either characteristic fragment ions or indicative constant neutral losses (CNLs) during tandem mass spectrometry allowing a selective and sensitive analysis of cross-linked products. The new derivatizing reagent for chemical cross-linking solely contains a thiourea moiety that is flanked by two amine-reactive N-hydroxy succinimide (NHS) ester moieties for reaction with lysines or free N-termini in proteins. The new reagent offers simple synthetic access and easy structural variation of either length or functionalities at both ends. The thiourea moiety exhibits specifically tailored CID fragmentation capabilities--a characteristic CNL of 85 u--ensuring a reliable detection of derivatized peptides by both electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry and as such possesses a versatile applicability for chemical cross-linking studies. A detailed examination of the CID behavior of the presented thiourea-based reagent reveals that slight structural variations of the reagent will be necessary to ensure its comprehensive and efficient application for chemical cross-linking of proteins.

  7. Expression profiling and cross-species RNA interference (RNAi) of desiccation-induced transcripts in the anhydrobiotic nematode Aphelenchus avenae

    PubMed Central

    2010-01-01

    Background Some organisms can survive extreme desiccation by entering a state of suspended animation known as anhydrobiosis. The free-living mycophagous nematode Aphelenchus avenae can be induced to enter anhydrobiosis by pre-exposure to moderate reductions in relative humidity (RH) prior to extreme desiccation. This preconditioning phase is thought to allow modification of the transcriptome by activation of genes required for desiccation tolerance. Results To identify such genes, a panel of expressed sequence tags (ESTs) enriched for sequences upregulated in A. avenae during preconditioning was created. A subset of 30 genes with significant matches in databases, together with a number of apparently novel sequences, were chosen for further study. Several of the recognisable genes are associated with water stress, encoding, for example, two new hydrophilic proteins related to the late embryogenesis abundant (LEA) protein family. Expression studies confirmed EST panel members to be upregulated by evaporative water loss, and the majority of genes was also induced by osmotic stress and cold, but rather fewer by heat. We attempted to use RNA interference (RNAi) to demonstrate the importance of this gene set for anhydrobiosis, but found A. avenae to be recalcitrant with the techniques used. Instead, therefore, we developed a cross-species RNAi procedure using A. avenae sequences in another anhydrobiotic nematode, Panagrolaimus superbus, which is amenable to gene silencing. Of 20 A. avenae ESTs screened, a significant reduction in survival of desiccation in treated P. superbus populations was observed with two sequences, one of which was novel, while the other encoded a glutathione peroxidase. To confirm a role for glutathione peroxidases in anhydrobiosis, RNAi with cognate sequences from P. superbus was performed and was also shown to reduce desiccation tolerance in this species. Conclusions This study has identified and characterised the expression profiles of members

  8. Volume change of double cross-linked poly(aspartic acid) hydrogels induced by cleavage of one of the crosslinks.

    PubMed

    Zrinyi, Miklos; Gyenes, Tamas; Juriga, David; Kim, Ji-Heung

    2013-02-01

    In the present paper we report for the first time the development of redox-responsive biocompatible polymer gels. Double cross-linked poly(aspartic acid) hydrogels were prepared using two different cross-linking agents simultaneously. One of the cross-linkers was diaminobutane (DAB), the other cystamine (CYS). The relative amounts of DAB and CYS molecules were varied over a wide range while the total amount of cross-linker molecules (DAB+CYS) was kept constant. DAB provides stable cross-links, whereas CYS contains disulfide bonds, which can be broken by reduction. The cleavage of disulfide cross-links results in enhanced swelling and a significant decrease in the elastic modulus of the gels. These novel types of stimuli-responsive gels are promising candidates for new swelling controlled release matrices. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Cross-Taxa Similarities in Affect-Induced Changes of Vocal Behavior and Voice in Arboreal Monkeys

    PubMed Central

    Lemasson, Alban; Remeuf, Kevin; Rossard, Arnaud; Zimmermann, Elke

    2012-01-01

    Measuring the affective state of an individual across species with comparable non-invasive methods is a current challenge in animal communication research. This study aims to explore to which extent affect intensity is conveyed in the vocal behaviours of three nonhuman primate species (Campbell's monkeys, De Brazza's monkeys, red-capped mangabeys), which vary in body size, ecological niche and social system. Similarly in the three species, we experimentally induced a change in captive social groups' affect by locking all group members together in their outside enclosure. The two experimental conditions which varied in affect intensity consisted in imposing a pre-reunion 90 mn-separation by splitting up the respective group into two subgroups (High affect condition) or not (Low affect condition). We measured call rates as well as voice features at the time of reunion in both conditions. The three studied species reacted in a very similar way. Across species, call rates changed significantly between the behaviourally defined states. Furthermore, contact call duration and, to some extent, voice pitch increased. Our results suggest, for the first time in arboreal Old World monkeys, that affect intensity is conveyed reliably in vocal behaviour and specific acoustic characteristics of voice, irrespective of body size and ecological niche differences between species. Cross-taxa similarities in acoustic cues of affect intensity point to phylogenetic constraints and inheritance from a common ancestor, whereas variations in vocal behaviour and affect intensity-related acoustic cues between species may be an adaptation to specific social requirements and depend on social systems. Our findings as well as a comparison with published works on acoustic communication in other vertebrate groups support the hypothesis that affect intensity in human voice originates from precursors already found deep inside the vertebrate phylogeny. PMID:22984618

  10. In situ TEM characterization of shear-stress-induced interlayer sliding in the cross section view of molybdenum disulfide.

    PubMed

    Oviedo, Juan Pablo; KC, Santosh; Lu, Ning; Wang, Jinguo; Cho, Kyeongjae; Wallace, Robert M; Kim, Moon J

    2015-02-24

    The experimental study of interlayer sliding at the nanoscale in layered solids has been limited thus far by the incapability of mechanical and imaging probes to simultaneously access sliding interfaces and overcome through mechanical stimulus the van der Waals and Coulombic interactions holding the layers in place. For this purpose, straightforward methods were developed to achieve interlayer sliding in molybdenum disulfide (MoS2) while under observation within a transmission electron microscope. A method to manipulate, tear, and slide free-standing atomic layers of MoS2 is demonstrated by electrostatically coupling it to an oxidized tungsten probe attached to a micromanipulator at a bias above ±7 V. A first-principles model of a MoS2 bilayer polarized by a normal electric field of 5 V/nm, emanating from the tip, demonstrates the appearance of a periodic negative sliding potential energy barrier when the layers slide into the out-of-registry stacking configuration, hinting at electrostatic gating as a means of modifying the interlayer tribology to facilitate shear exfoliation. A method to shear focused ion beam prepared MoS2 cross section samples using a nanoindenter force sensor is also demonstrated, allowing both the observation and force measurement of its interlayer dynamics during shear-induced sliding. From this experiment, the zero normal load shear strength of MoS2 can be directly obtained: 25.3 ± 0.6 MPa. These capabilities enable the site-specific mechanical testing of dry lubricant-based nanoelectromechanical devices and can lead to a better understanding of the atomic mechanisms from which the interlayer tribology of layered materials originates.

  11. Neutron-induced fission cross section of Np237 in the keV to MeV range at the CERN n_TOF facility

    DOE PAGES

    Diakaki, M.; Karadimos, D.; Vlastou, R.; ...

    2016-03-17

    We experimentally determined the neutron-induced fission cross section of Np-237 at the high-resolution and high-intensity facility n_TOF, at CERN, in the energy range 100 keV to 9 MeV, using the U-235(n, f) and U-238(n, f) cross section standards below and above 2 MeV, respectively. Moreover, a fast ionization chamber was used in order to detect the fission fragments from the reactions and the targets were characterized as far as their mass and homogeneity are concerned by means of a spectroscopy and Rutherford backscattering spectroscopy respectively. Finally, theoretical calculations within the Hauser-Feshbach formalism have been performed, employing the EMPIRE code, andmore » the model parameters were tuned in order to successfully reproduce the experimental fission cross-sectional data and simultaneously all the competing reaction channels.« less

  12. Neutron-induced fission cross section of 237Np in the keV to MeV range at the CERN n_TOF facility

    NASA Astrophysics Data System (ADS)

    Diakaki, M.; Karadimos, D.; Vlastou, R.; Kokkoris, M.; Demetriou, P.; Skordis, E.; Tsinganis, A.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviani, M.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; David, S.; Dolfini, R.; Domingo-Pardo, C.; Dorochenko, A.; Dridi, W.; Duran, I.; Eleftheriadis, Ch.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Fuji, K.; Furman, W.; Goncalves, I.; Gallino, R.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Ioannidis, K.; Isaev, S.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karamanis, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Kolokolov, D.; Konovalov, V.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Massimi, C.; Mastinu, P.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Sedysheva, M.; Stamoulis, K.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Voss, F.; Wendler, H.; Wiescher, M.; Wisshak, K.; n TOF Collaboration

    2016-03-01

    The neutron-induced fission cross section of 237Np was experimentally determined at the high-resolution and high-intensity facility n_TOF, at CERN, in the energy range 100 keV to 9 MeV, using the 235U(n ,f ) and 238U(n ,f ) cross section standards below and above 2 MeV, respectively. A fast ionization chamber was used in order to detect the fission fragments from the reactions and the targets were characterized as far as their mass and homogeneity are concerned by means of α spectroscopy and Rutherford backscattering spectroscopy respectively. Theoretical calculations within the Hauser-Feshbach formalism have been performed, employing the empire code, and the model parameters were tuned in order to successfully reproduce the experimental fission cross-sectional data and simultaneously all the competing reaction channels.

  13. Extension of the energy range of experimental activation cross-sections data of deuteron induced nuclear reactions on indium up to 50MeV.

    PubMed

    Tárkányi, F; Ditrói, F; Takács, S; Hermanne, A; Ignatyuk, A V

    2015-11-01

    The energy range of our earlier measured activation cross-sections data of longer-lived products of deuteron induced nuclear reactions on indium were extended from 40MeV up to 50MeV. The traditional stacked foil irradiation technique and non-destructive gamma spectrometry were used. No experimental data were found in literature for this higher energy range. Experimental cross-sections for the formation of the radionuclides (113,110)Sn, (116m,115m,114m,113m,111,110g,109)In and (115)Cd are reported in the 37-50MeV energy range, for production of (110)Sn and (110g,109)In these are the first measurements ever. The experimental data were compared with the results of cross section calculations of the ALICE and EMPIRE nuclear model codes and of the TALYS 1.6 nuclear model code as listed in the on-line library TENDL-2014.

  14. Fission cross section of the 232Th(n,f)131Sb reaction induced by neutrons around 14 MeV

    NASA Astrophysics Data System (ADS)

    Zhang, Yi; Lv, Tao; Pan, Xiao-dong; Wang, Qiang; Fang, Kai-hong; Lan, Chang-lin

    2017-06-01

    In order to make a more detailed study on the 232Th fission process, the cross section of 232Th(n,f)131Sb fission reaction induced by 14 MeV neutrons was measured precisely with the neutron activation method and off-line gamma ray spectrometric technique. Neutron flux was monitored on line using the accompanying α particle from T(d,n)4He reaction in the irradiation and neutron energies were given by the cross section ratio of 90Zr(n,2 n)89Zr reaction to 93Nb(n,2 n)92 mNb reaction. The experimentally determined cross sections were deduced to be 6.27±0.47, 6.19±0.54, 6.00±0.51 mb at 14.1±0.3, 14.5±0.3 and 14.8±0.3 MeV, respectively.

  15. Cross sections for nuclide production in proton- and deuteron-induced reactions on 93Nb measured using the inverse kinematics method

    NASA Astrophysics Data System (ADS)

    Nakano, Keita; Watanabe, Yukinobu; Kawase, Shoichiro; Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Takeuchi, Satoshi; Togano, Yasuhiro; Nakamura, Takashi; Maeda, Yukie; Ahn, Deuk Soon; Aikawa, Masayuki; Araki, Shouhei; Chen, Sidong; Chiga, Nobuyuki; Doornenbal, Pieter; Fukuda, Naoki; Ichihara, Takashi; Isobe, Tadaaki; Kawakami, Shunsuke; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubo, Toshiyuki; Kubono, Shigeru; Kurokawa, Meiko; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Taniuchi, Ryo; Tsubota, Jun'ichi; Watanabe, Yasushi; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

    2017-09-01

    Isotopic production cross sections were measured for proton- and deuteron-induced reactions on 93Nb by means of the inverse kinematics method at RIKEN Radioactive Isotope Beam Factory. The measured production cross sections of residual nuclei in the reaction 93Nb + p at 113 MeV/u were compared with previous data measured by the conventional activation method in the proton energy range between 46 and 249 MeV. The present inverse kinematics data of four reaction products (90Mo, 90Nb, 88Y, and 86Y) were in good agreement with the data of activation measurement. Also, the model calculations with PHITS describing the intra-nuclear cascade and evaporation processes generally well reproduced the measured isotopic production cross sections.

  16. The cross section functions for neutron induced reactions with Rhenium in the energy range 13.0-19.5 MeV

    NASA Astrophysics Data System (ADS)

    Jovančević, N.; Daraban, L.; Stroh, H.; Oberstedt, S.; Hult, M.; Bonaldi, C.; Geerts, W.; Hambsch, F.-J.; Lutter, G.; Marissens, G.; Vidali, M.

    2017-09-01

    The technique for measuring neutron activation cross-sections using wide energy neutron beams (NAXSUN) was recently developed at JRC-Geel . This method is based on the detection of the gamma activity induced by the activation of the samples in different but overlapping neutron fields and following an unfolding procedure. In the present work, measurements of the cross-section functions by the NAXSUN technique for the (n,a), (n,2n), (n,p) and (n,3n) reactions on rhenium isotopes 185Re and 187Re were performed. The results are the first experimental data for the mentioned reaction cross-sections in the energy range 13.0-19.5 MeV. The obtained data are of interest for possible applications of Re in nuclear technology and medicine.

  17. Neutron-induced fission cross section of natPb and Bi209 from threshold to 1 GeV: An improved parametrization

    NASA Astrophysics Data System (ADS)

    Tarrío, D.; Tassan-Got, L.; Audouin, L.; Berthier, B.; Duran, I.; Ferrant, L.; Isaev, S.; Le Naour, C.; Paradela, C.; Stephan, C.; Trubert, D.; Abbondanno, U.; Aerts, G.; Álvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Badurek, G.; Baumann, P.; Bečvář, F.; Belloni, F.; Berthoumieux, E.; Calviño, F.; Calviani, M.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Carrillo de Albornoz, A.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Dolfini, R.; Domingo-Pardo, C.; Dridi, W.; Eleftheriadis, C.; Embid-Segura, M.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Fujii, K.; Furman, W.; Goncalves, I.; González-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Kadi, Y.; Käppeler, F.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krtička, M.; Lampoudis, C.; Leeb, H.; Lederer, C.; Lindote, A.; Lopes, I.; Losito, R.; Lozano, M.; Lukic, S.; Marganiec, J.; Marques, L.; Marrone, S.; Martínez, T.; Massimi, C.; Mastinu, P.; Mendoza, E.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Oshima, M.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Sarmento, R.; Savvidis, I.; Tagliente, G.; Tain, J. L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescher, M.; Wisshak, K.

    2011-04-01

    Neutron-induced fission cross sections for natPb and Bi209 were measured with a white-spectrum neutron source at the CERN Neutron Time-of-Flight (n_TOF) facility. The experiment, using neutrons from threshold up to 1 GeV, provides the first results for these nuclei above 200 MeV. The cross sections were measured relative to U235 and U238 in a dedicated fission chamber with parallel plate avalanche counter detectors. Results are compared with previous experimental data. Upgraded parametrizations of the cross sections are presented, from threshold energy up to 1 GeV. The proposed new sets of fitting parameters improve former results along the whole energy range.

  18. Neutron-induced fission cross-section of 233U in the energy range 0.5 < En < 20 MeV

    NASA Astrophysics Data System (ADS)

    Belloni, F.; Calviani, M.; Colonna, N.; Mastinu, P.; Milazzo, P. M.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Käppeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martınez, T.; Massimi, C.; Meaze, M. H.; Mengoni, A.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K.

    2011-01-01

    The neutron-induced fission cross-section of 233U has been measured at the CERN n_TOF facility relative to the standard fission cross-section of 235U between 0.5 and 20MeV. The experiment was performed with a fast ionization chamber for the detection of the fission fragments and to discriminate against α -particles from the natural radioactivity of the samples. The high instantaneous flux and the low background of the n_TOF facility result in data with uncertainties of ≈ 3% , which were found in good agreement with previous experiments. The high quality of the present results allows to improve the evaluation of the 233U (n,f) cross-section and, consequently, the design of energy systems based on the Th/U cycle.

  19. Hepatitis C Virus Hypervariable Region 1 Variants Presented on Hepatitis B Virus Capsid-Like Particles Induce Cross-Neutralizing Antibodies

    PubMed Central

    Bankwitz, Dorothea; Osburn, William; Viazov, Sergei; Brovko, Olena; Zekri, Abdel-Rahman; Khudyakov, Yury; Nassal, Michael; Pumpens, Paul; Pietschmann, Thomas; Timm, Jörg; Roggendorf, Michael; Walker, Andreas

    2014-01-01

    Hepatitis C virus (HCV) infection is still a serious global health burden. Despite improved therapeutic options, a preventative vaccine would be desirable especially in undeveloped countries. Traditionally, highly conserved epitopes are targets for antibody-based prophylactic vaccines. In HCV-infected patients, however, neutralizing antibodies are primarily directed against hypervariable region I (HVRI) in the envelope protein E2. HVRI is the most variable region of HCV, and this heterogeneity contributes to viral persistence and has thus far prevented the development of an effective HVRI-based vaccine. The primary goal of an antibody-based HCV vaccine should therefore be the induction of cross-reactive HVRI antibodies. In this study we approached this problem by presenting selected cross-reactive HVRI variants in a highly symmetric repeated array on capsid-like particles (CLPs). SplitCore CLPs, a novel particulate antigen presentation system derived from the HBV core protein, were used to deliberately manipulate the orientation of HVRI and therefore enable the presentation of conserved parts of HVRI. These HVRI-CLPs induced high titers of cross-reactive antibodies, including neutralizing antibodies. The combination of only four HVRI CLPs was sufficient to induce antibodies cross-reactive with 81 of 326 (24.8%) naturally occurring HVRI peptides. Most importantly, HVRI CLPs with AS03 as an adjuvant induced antibodies with a 10-fold increase in neutralizing capability. These antibodies were able to neutralize infectious HCVcc isolates and 4 of 19 (21%) patient-derived HCVpp isolates. Taken together, these results demonstrate that the induction of at least partially cross-neutralizing antibodies is possible. This approach might be useful for the development of a prophylactic HCV vaccine and should also be adaptable to other highly variable viruses. PMID:25014219

  20. NEUTRON CROSS SECTION EVALUATIONS OF FISSION PRODUCTS BELOW THE FAST ENERGY REGION

    SciTech Connect

    OH,S.Y.; CHANG,J.; MUGHABGHAB,S.

    2000-05-11

    Neutron cross section evaluations of the fission-product isotopes, {sup 95}Mo, {sup 99}Tc, {sup 101}Ru, {sup 103}Rh, {sup 105}Pd, {sup 109}Ag, {sup 131}Xe, {sup 133}Cs, {sup 141}Pr, {sup 141}Nd, {sup 147}Sm, {sup 149}Sm, {sup 150}Sm, {sup 151}Sm, {sup 152}Sm, {sup 153}Eu, {sup 155}Gd, and {sup 157}Gd were carried out below the fast neutron energy region within the framework of the BNL-KAERI international collaboration. In the thermal energy region, the energy dependence of the various cross-sections was calculated by applying the multi-level Breit-Wigner formalism. In particular, the strong energy dependence of the coherent scattering lengths of {sup 155}Gd and {sup 157}Gd were determined and were compared with recent calculations of Lynn and Seeger. In the resonance region, the recommended resonance parameters, reported in the BNL compilation, were updated by considering resonance parameter information published in the literature since 1981. The s-wave and, if available, p-wave reduced neutron widths were analyzed in terms of the Porter-Thomas distribution to determine the average level spacings and the neutron strength functions. Average radiative widths were also calculated from measured values of resolved energy resonances. The average resonance parameters determined in this study were compared with those in the BNL and other compilations, as well as the ENDF/B-VI, JEF-2.2, and JENDL-3.2 data libraries. The unresolved capture cross sections of these isotopes, computed with the determined average resonance parameters, were compared with measurements, as well as the ENDF/B-VI evaluations. To achieve agreement with the measurements, in a few cases minor adjustments in the average resonance parameters were made. Because of astrophysical interest, the Maxwellian capture cross sections of these nuclides at a neutron temperature of 30 keV were computed and were compared with other compilations and evaluations.

  1. Measurement of double differential charged-particle emission cross sections for reactions induced by 26 MeV protons and FKK model analysis

    SciTech Connect

    Watanabe, Y.; Aoto, A.; Kashimoto, H.

    1994-06-01

    Double differential charged-particle emission cross sections of proton-induced reactions have been measured for {sup nat}C, {sup 27}Al, {sup nat}Si, {sup 98}Mo, {sup 106}Pd, {sup 159}Tb and {sup 181}Ta at energies around 26 MeV. Several (p,p{prime}) and (p,n) data for {sup 98}Mo and {sup 106}Pd in the incident energy range from 12 to 26 MeV are analysed in terms of the Feshbach-Kerman-Koonin model, in order to study preequilibrium nucleon emission from nucleon-induced reactions.

  2. Heparin-induced thrombocytopenia: cross-reactivity between standard heparin, low molecular weight heparin, dalteparin (Fragmin) and heparinoid, danaparoid (Orgaran).

    PubMed

    Ramakrishna, R; Manoharan, A; Kwan, Y L; Kyle, P W

    1995-11-01

    The incidence of cross-reactivity between unfractionated heparin and LMWH, fragmin, in patients with HIT is significantly lower (6/15, 40%) than hitherto reported in the literature. 7/9 patients with a negative cross-reactivity test were treated with dalteparin sodium (Fragmin) without any untoward events.

  3. Characteristics of HPV-Specific Antibody Responses Induced by Infection and Vaccination: Cross-Reactivity, Neutralizing Activity, Avidity and IgG Subclasses

    PubMed Central

    Scherpenisse, Mirte; Schepp, Rutger M.; Mollers, Madelief; Meijer, Chris J. L. M.; Berbers, Guy A. M.; van der Klis, Fiona R. M.

    2013-01-01

    Objectives In order to assess HPV-specific IgG characteristics, we evaluated multiple aspects of the humoral antibody response that will provide insight in the HPV humoral immune response induced by HPV infection and vaccination. Methods Cross-reactivity of HPV-specific antibodies induced by infection or vaccination was assessed with VLP16 or 18 inhibition using a VLP-based multiplex immunoassay (MIA) for HPV16, 18, 31, 33, 45, 52 and 58. HPV16/18 specific IgG1-4 subclasses and avidity were determined with the VLP-MIA in sera after HPV infection and after vaccination. Neutralizing antibodies were determined in a small subset of single-seropositive and multi-seropositive naturally derived antibodies. Results Naturally derived antibodies from single-positive sera were highly genotype-specific as homologue VLP-inhibition percentages varied between 78-94%. In multi-positive sera, cross-reactive antibodies were observed both within and between α7 and α9 species. After vaccination, cross-reactive antibodies were mainly species-specific. Avidity of vaccine-derived HPV-specific antibodies was 3 times higher than that of antibodies induced by HPV infection (p<0.0001). IgG1 and IgG3 were found to be the predominant subclasses observed after HPV infection and vaccination. In the small subset tested, the number of single-positive sera with neutralizing capacity was higher than of multi-positive sera. Conclusion Naturally derived HPV-specific antibodies from single-positive samples showed different characteristics in terms of cross-reactivity and neutralizing capacity compared with antibodies from multi-positive sera. Post-vaccination, HPV antibody avidity was approximately 3 times higher than antibody avidity induced by HPV infection. Therefore, antibody avidity might be a potential surrogate of protection. PMID:24058629

  4. Measurements of the neutron-induced fission cross section of sup 242 Cm and sup 238 Pu by lead slowing down time spectrometer

    SciTech Connect

    Alam, B.

    1987-01-01

    The neutron-induced fission cross section of {sup 242}Cm and {sup 238}Pu have been measured from 0.1 eV to 100 keV energy range using the Rensselaer Polytechnic Institute's Gaerttner Laboratory Electron Linac as a pulsed neutron source and the Rensselaer Intense Neutron Spectrometer (RINS) system to obtain an adequate ratio of the neutron-induced fission signal to that due to spontaneous fission background. A special fission chamber design employing multiple pairs of hemispherical electrodes coupled with fast electronics ({approx}nsec rise-time) combine to suppress the alpha pileup effects. The fission cross section of {sup 242}Cm and {sup 238}Pu reported in this thesis were obtained from simultaneous measurements on {sup 235}U, {sup 238}Pu and {sup 242}Cm, and these data were normalized to the resolution-broadened ENDF/B-V {sup 235} U fission cross section. The fission areas and the widths for the resolved low-energy resonances of {sup 242}Cm and {sup 238}Pu were determined. The resolution-broadened ENDF/B-V {sup 238}Pu fission data are generally in poor agreement with the measured fission data and a new evaluation on {sup 238}Pu has been recommended. The measured fission cross section of {sup 242}Cm cannot be compared because no evaluation or measurement on this nuclide is available in the energy region of the present measurements.

  5. Effect of wave function on the proton induced L XRP cross sections for {sub 62}Sm and {sub 74}W

    SciTech Connect

    Shehla,; Kaur, Rajnish; Kumar, Anil; Puri, Sanjiv

    2015-08-28

    The L{sub k}(k= 1, α, β, γ) X-ray production cross sections have been calculated for {sub 74}W and {sub 62}Sm at different incident proton energies ranging 1-5 MeV using theoretical data sets of different physical parameters, namely, the Li(i=1-3) sub-shell X-ray emission rates based on the Dirac-Fork (DF) model, the fluorescence and Coster Kronig yields based on the Dirac- Hartree-Slater (DHS) model and two sets the proton ionization cross sections based on the DHS model and the ECPSSR in order to assess the influence of the wave function on the XRP cross sections. The calculated cross sections have been compared with the measured cross sections reported in the recent compilation to check the reliability of the calculated values.

  6. An ultraviolet-inducible adenosine-adenosine cross-link reflects the catalytic structure of the Tetrahymena ribozyme

    SciTech Connect

    Downs, W.D.; Cech, T.R. )

    1990-06-12

    When a shortened enzymatic version of the Tetrahymena self-splicing intervening sequence (IVS) RNA is placed under catalytic conditions and irradiated at 254 nm, a covalent cross-link forms with high efficiency. The position of the cross-link was mapped by using three independent methods: RNase H digestion, primer extension with reverse transcriptase, and partial hydrolysis of end-labeled RNA. The cross-link is chemically unusual in that it joins two adenosines, A57 and A95. Formation of this cross-link depends upon the identity and concentration of divalent cations present and upon heat-cool renaturation of the IVS in a manner that parallels conditions required for optimal catalytic activity. Furthermore, cross-linking requires the presence of sequences within the core structure, which is conserved among group I intervening sequences and necessary for catalytic activity. Together these correlations suggest that a common folded structure permits cross-linking and catalytic activity. The core can form this structure independent of the presence of P1 and elements at the 3' end of the IVS. The cross-linked RNA loses catalytic activity under destabilizing conditions, presumably due to disruption of the folded structure by the cross-link. One of the nucleotides participating in this cross-link is highly conserved (86%) within the secondary structure of group I intervening sequences. We conclude that A57 and A95 are precisely aligned in a catalytically active conformation of the RNA. A model is presented for the tertiary arrangement in the vicinity of the cross-link.

  7. Treatment of progressive keratoconus by riboflavin-UVA-induced cross-linking of corneal collagen: ultrastructural analysis by Heidelberg Retinal Tomograph II in vivo confocal microscopy in humans.

    PubMed

    Mazzotta, Cosimo; Balestrazzi, Angelo; Traversi, Claudio; Baiocchi, Stefano; Caporossi, Tomaso; Tommasi, Cristina; Caporossi, Aldo

    2007-05-01

    To assess ultrastructural stromal modifications after riboflavin-UVA-induced cross-linking of corneal collagen in patients with progressive keratoconus. This was a second-phase prospective nonrandomized open study in 10 patients with progressive keratoconus treated by riboflavin-UVA-induced cross-linking of corneal collagen and assessed by means of Heidelberg Retinal Tomograph II Rostock Corneal Module (HRT II-RCM) in vivo confocal microscopy. The eye in the worst clinical condition was treated for each patient. Treatment under topical anesthesia included corneal deepithelization (9-mm diameter) and instillation of 0.1% riboflavin phosphate-20% dextran T 500 solution at 5 minutes before UVA irradiation and every 5 minutes for a total of 30 minutes. UVA irradiation was 7 mm in diameter. Patients were assessed by HRT II-RCM confocal microscopy in vivo at 1, 3, and 6 months after treatment. Rarefaction of keratocytes in the anterior and intermediate stroma, associated with stromal edema, was observed immediately after treatment. The observation at 3 months after the operation detected keratocyte repopulation in the central treated area, whereas the edema had disappeared. Cell density increased progressively over the postoperative period. At approximately 6 months, keratocyte repopulation was complete, accompanied by increased density of stromal fibers. No endothelial damage was observed at any time. Reduction in anterior and intermediate stromal keratocytes followed by gradual repopulation has been confirmed directly in vivo in humans by HRT II-RCM confocal microscopy after riboflavin-UVA-induced corneal collagen cross-linking.

  8. Gamma-ray production cross sections in multiple channels for neutron induced reaction on 48Ti for En=1 to 200 MeV

    SciTech Connect

    Dashdorj, D; Mitchell, G E; Garrett, P E; Agvaanluvsan, U; Becker, J A; Bernstein, L A; Chadwick, M B; Devlin, M; Fotiades, N; Kawano, T; Nelson, R O; Younes, W

    2006-07-06

    Prompt {gamma}-ray production cross sections were measured on a {sup 48}Ti sample for incident neutron energies from 1 MeV to 200 MeV. Partial {gamma}-ray cross sections for transitions in {sup 45-48}Ti, {sup 45-48}Sc, and {sup 43-45}Ca were determined. The observation of about 130 transitions from 11 different isotopes in the present work provides a demanding test of reaction model calculations, and is the first study in this mass region to extract partial {gamma}-ray cross sections for many different reaction channels over a wide range of incident neutron energies. The neutrons were produced by the Los Alamos National Laboratory spallation neutron source located at the LANSCE/WNR facility. The prompt-reaction {gamma} rays were detected with the large-scale Compton-suppressed GErmanium Array for Neutron Induced Excitations (GEANIE). Event neutron energies were determined by the time-of-flight technique. The {gamma}-ray excitation functions were converted to partial {gamma}-ray cross sections and then compared with model calculations using the enhanced GNASH reaction code. Compound nuclear, pre-equilibrium emission and direct reaction mechanisms are included. Overall the model calculations of the partial {gamma}-ray cross sections are in good agreement with measured values.

  9. Outer membrane vesicles derived from Salmonella Typhimurium mutants with truncated LPS induce cross-protective immune responses against infection of Salmonella enterica serovars in the mouse model.

    PubMed

    Liu, Qiong; Liu, Qing; Yi, Jie; Liang, Kang; Liu, Tian; Roland, Kenneth L; Jiang, Yanlong; Kong, Qingke

    2016-12-01

    Salmonella enterica cause diarrheal and systemic diseases and are of considerable concern worldwide. Vaccines that are cross-protective against multiple serovars could provide effective control of Salmonella-mediated diseases. Bacteria-derived outer membrane vesicles (OMVs) are highly immunogenic and are capable of eliciting protective immune responses. Alterations in lipopolysaccharide (LPS) length can result in outer membrane remodeling and composition of outer membrane proteins (OMPs) changing. In this study, we investigated the impact of truncated LPS on both the production and immunogenicity of Salmonella OMVs, including the ability of OMVs to elicit cross-protection against challenge by heterologous Salmonella strains. We found that mutations in waaJ and rfbP enhanced vesiculation, while mutations in waaC, waaF and waaG inhibited this process. Animal experiments indicated that OMVs from waaC, rfaH and rfbP mutants induced stronger serum immune responses compared to OMVs from the parent strain, while all elicited protective responses against the wild-type S. Typhimurium challenge. Furthermore, intranasal or intraperitoneal immunization with OMVs derived from the waaC and rfbP mutants elicited significantly higher cross-reactive IgG responses and provided enhanced cross-protection against S. Choleraesuis and S. Enteritidis challenge than the wild-type OMVs. These results indicate that truncated-LPS OMVs are capable of conferring cross protection against multiple serotypes of Salmonella infection.

  10. Outer membrane vesicles from flagellin-deficient Salmonella enterica serovar Typhimurium induce cross-reactive immunity and provide cross-protection against heterologous Salmonella challenge

    PubMed Central

    Liu, Qiong; Liu, Qing; Yi, Jie; Liang, Kang; Hu, Bo; Zhang, Xiangmin; Curtiss, Roy; Kong, Qingke

    2016-01-01

    Outer membrane vesicles (OMVs) isolated from Salmonella Typhimurium are potentially useful for developing subunit vaccines because of high immunogenicity and protective efficacy. However, flagella might remain in OMV pellets following OMV purification, resulting in non-essential immune responses and counteraction of bacterial protective immune responses when developing a vaccine against infection of multiple serotypes Salmonella. In this study, a flagellin-deficient S. Typhimurium mutant was constructed. Lipopolysaccharide profiles, protein profiles and cryo-electron microscopy revealed that there were no significant differences between the wild-type and mutant OMVs, with the exception of a large amount of flagellin in the wild-type OMVs. Neither the wild-type OMVs nor the non-flagellin OMVs were toxic to macrophages. Mice immunized with the non-flagellin OMVs produced high concentrations of IgG. The non-flagellin OMVs elicited strong mucosal antibody responses in mice when administered via the intranasal route in addition to provoking higher cross-reactive immune responses against OMPs isolated from S. Choleraesuis and S. Enteritidis. Both intranasal and intraperitoneal immunization with the non-flagellin OMVs provided efficient protection against heterologous S. Choleraesuis and S. Enteritidis challenge. Our results indicate that the flagellin-deficient OMVs may represent a new vaccine platform that could be exploited to facilitate the production of a broadly protective vaccine. PMID:27698383

  11. Endothelin plays a role in contractions of isolated pig pulmonary vessels induced by diaspirin cross-linked hemoglobin.

    PubMed

    Ledvina, M A; Hart, J; Bina, S; Jing, M; Muldoon, S

    1999-05-01

    The current studies were undertaken to investigate the role of endothelin-1 (ET-1) and its receptors in contractions of isolated pulmonary vessels of the pig induced by diaspirin cross-linked hemoglobin (DCLHb). Second-order pulmonary arteries (PAs) and veins (PVs) were isolated from pigs, cut into rings (4 to 5 mm), and mounted at optimal passive tension in 37 degrees C Krebs-filled tissue baths bubbled with 95% O2/5% CO2. Isometric tension was recorded continuously. In paired rings, concentration responses to ET-1 (10(-10) to 10(-7) mol/L), DCLHb (10(-9) to 3x10(-6) mol/L), and N-nitro-L-arginine (LNA) (10(-6) to 5x10(-5) mol/L) in the presence and absence of the ET(A) receptor antagonist BQ123 (3x10(-5) mol/L) were determined. PVs and PAs with intact endothelium and rings from which the endothelium was removed (denuded) were pretreated with the ET(B) receptor antagonist BQ788 to determine the contribution of ET(B) receptors to ET-1, DCLHb, and LNA responses. ET-1, DCLHb, and LNA caused concentration-dependent increases in tension in all vessels. In the presence of BQ123, the 50% effective concentration (EC50) of ET-1 was significantly increased (by 5-fold to 10-fold) in all vessels. DCLHb concentration responses were significantly attenuated-in the PVs by 45% and in the PAs by 79%-during treatment with BQ123. BQ123 attenuated LNA responses in PVs by 35% and in PAs by 87%. Treatment with BQ788 had no effect on endothelium-intact PVs or PAs but significantly increased ET-1 EC50 (log of the molar concentration) from -9.0+/-0.22 to -7.8+/-0.05 in denuded PAs. The ET-1 EC50 was significantly decreased in denuded PAs (-9.0+/-0.22) as compared with responses in endothelium-intact PAs (-8.1+/-0.18). DCLHb concentration responses were attenuated by 71% and LNA responses by 80% during antagonism with BQ788 in the intact PAs only. These data demonstrate that ET-1 plays a role in DCLHb-induced contractions in the PA and PV. The contributions of ET are mediated by both ET

  12. Design and synthesis of curcumin analogues for in vivo fluorescence imaging and inhibiting copper-induced cross-linking of amyloid beta species in Alzheimer's disease.

    PubMed

    Zhang, Xueli; Tian, Yanli; Li, Zeng; Tian, Xiaoyu; Sun, Hongbin; Liu, Hong; Moore, Anna; Ran, Chongzhao

    2013-11-06

    In this article, we first designed and synthesized curcumin-based near-infrared (NIR) fluorescence imaging probes for detecting both soluble and insoluble amyloid beta (Aβ) species and then an inhibitor that could attenuate cross-linking of Aβ induced by copper. According to our previous results and the possible structural stereohindrance compatibility of the Aβ peptide and the hydrophobic/hydrophilic property of the Aβ13-20 (HHQKLVFF) fragment, NIR imaging probe CRANAD-58 was designed and synthesized. As expected CRANAD-58 showed significant fluorescence property changes upon mixing with both soluble and insoluble Aβ species in vitro. In vivo NIR imaging revealed that CRANAD-58 was capable of differentiating transgenic and wild-type mice as young as 4 months old, the age that lacks apparently visible Aβ plaques and Aβ is likely in its soluble forms. According to our limited studies on the interaction mechanism between CRANAD-58 and Aβ, we also designed CRANAD-17 to attenuate the cross-linking of Aβ42 induced by copper. It is well-known that the coordination of copper with imidazoles on Histidine-13 and 14 (H13, H14) of Aβ peptides could initialize covalent cross-linking of Aβ. In CRANAD-17, a curcumin scaffold was used as an anchoring moiety to usher the designed compound to the vicinity of H13 and H14 of Aβ, and imidazole rings were incorporated to compete with H13/H14 for copper binding. The results of SDS-PAGE gel and Western blot indicated that CRANAD-17 was capable of inhibiting Aβ42 cross-linking induced by copper. This raises a potential for CRANAD-17 to be considered for AD therapy.

  13. 1,2,3,4-Diepoxybutane-Induced DNA-Protein Cross-Linking in Human Fibrosarcoma (HT1080) Cells

    PubMed Central

    Gherezghiher, Teshome B.; Ming, Xun; Villalta, Peter; Campbell, Colin; Tretyakova, Natalia Y.

    2013-01-01

    1,2,3,4-diepoxybutane (DEB) is the key carcinogenic metabolite of 1,3-butadiene (BD), an important industrial and environmental chemical present in urban air and in cigarette smoke. DEB is a genotoxic bis-electrophile capable of cross-linking cellular biomolecules to form DNA-DNA and DNA-protein cross-links (DPCs). In the present work, mass spectrometry-based proteomics was employed to characterize DEB-mediated DNA-protein cross-linking in human fibrosarcoma (HT1080) cells. Over 150 proteins including histones, high mobility group proteins, transcription factors, splicing factors, and tubulins were found among those covalently cross-linked to chromosomal DNA in the presence of DEB. A large portion of the cross-linked proteins are known factors involved in DNA binding, transcriptional regulation, cell signaling, DNA repair, and DNA damage response. HPLC-ESI+-MS/MS analysis of total proteolytic digests revealed the presence of 1-(S-cysteinyl)-4-(guan-7-yl)-2,3-butanediol conjugates, confirming that DEB forms DPCs between cysteine thiols within proteins and the N-7 guanine positions within DNA. However, relatively high concentrations of DEB were required to achieve significant DPC formation, indicating that it is a poor cross-linking agent as compared to antitumor nitrogen mustards and platinum compounds. PMID:23506368

  14. 1,2,3,4-Diepoxybutane-induced DNA-protein cross-linking in human fibrosarcoma (HT1080) cells.

    PubMed

    Gherezghiher, Teshome B; Ming, Xun; Villalta, Peter W; Campbell, Colin; Tretyakova, Natalia Y

    2013-05-03

    1,2,3,4-Diepoxybutane (DEB) is the key carcinogenic metabolite of 1,3-butadiene (BD), an important industrial and environmental chemical present in urban air and in cigarette smoke. DEB is a genotoxic bis-electrophile capable of cross-linking cellular biomolecules to form DNA-DNA and DNA-protein cross-links (DPCs). In the present work, mass spectrometry-based proteomics was employed to characterize DEB-mediated DNA-protein cross-linking in human fibrosarcoma (HT1080) cells. Over 150 proteins including histones, high mobility group proteins, transcription factors, splicing factors, and tubulins were found among those covalently cross-linked to chromosomal DNA in the presence of DEB. A large portion of the cross-linked proteins are known factors involved in DNA binding, transcriptional regulation, cell signaling, DNA repair, and DNA damage response. HPLC-ESI(+)-MS/MS analysis of total proteolytic digests revealed the presence of 1-(S-cysteinyl)-4-(guan-7-yl)-2,3-butanediol conjugates, confirming that DEB forms DPCs between cysteine thiols within proteins and the N-7 guanine positions within DNA. However, relatively high concentrations of DEB were required to achieve significant DPC formation, indicating that it is a poor cross-linking agent as compared to antitumor nitrogen mustards and platinum compounds.

  15. Formation of retinoid X receptor homodimers leads to repression of T3 response: hormonal cross talk by ligand-induced squelching.

    PubMed Central

    Lehmann, J M; Zhang, X K; Graupner, G; Lee, M O; Hermann, T; Hoffmann, B; Pfahl, M

    1993-01-01

    Thyroid hormone receptors (TRs) form heterodimers with retinoid X receptors (RXRs). Heterodimerization is required for efficient TR DNA binding to most response elements and transcriptional activation by thyroid hormone. RXRs also function as auxiliary proteins for several other receptors. In addition, RXR alpha can be induced by specific ligands to form homodimers. Here we report that RXR-specific retinoids that induce RXR homodimers are effective repressors of the T3 response. We provide evidence that this repression by RXR-specific ligands occurs by sequestering of RXR from TR-RXR heterodimers into RXR homodimers. This ligand-induced squelching may represent an important mechanism by which RXR-specific retinoids and 9-cis retinoic acid mediate hormonal cross talk among a subfamily of nuclear receptors activated by structurally unrelated ligands. Images PMID:8246986

  16. Therapeutic effect of pirenzepine for clozapine-induced hypersalivation: a randomized, double-blind, placebo-controlled, cross-over study.

    PubMed

    Bai, Y M; Lin, C C; Chen, J Y; Liu, W C

    2001-12-01

    The objective of this study was to investigate the efficacy of pirenzepine in the treatment of clozapine-induced hypersalivation. Pirenzepine is reported to counteract hypersalivation by its selective antagonistic activity on the M4-muscarinic receptor, which is stimulated by clozapine. Twenty patients with clozapine-induced hypersalivation underwent a random-order, double-blind, placebo-controlled, cross-over trial which lasted 8 weeks each for the pirenzepine and placebo investigations, with a 4-week washout period in between. The severity of hypersalivation was assessed using an objective measure: saliva production monitored through the diameter of wetted surface on tissue paper placed over the patient's pillow. Our study showed that pirenzepine had no significant therapeutic effect on hypersalivation compared with placebo, suggesting that hypersalivation induced by clozapine might have a neurobiological basis other than the M4-muscarinic receptor.

  17. Measurement of fission cross section for 232Th (n,f) 131 ZX ( Z = 50 , 51, 52, 53) reaction induced by neutrons around 14 MeV

    NASA Astrophysics Data System (ADS)

    Lan, Chang-lin; Qiu, Yi-jia; Wang, Qiang; Zhang, Zheng-wei; Zhang, Qian; Tan, Jun-cai; Lai, Cai-feng; Fang, Kai-hong

    2017-06-01

    The fission cross sections of 232Th (n,f) 131m, gSn , 232Th (n,f) 131Sb , 232Th (n,f) 131m, gTe , 232Th (n,f) 131I fission reactions induced by 14MeV neutrons were measured precisely with the neutron activation technique. The neutron flux was monitored by accompanying α particle in the irradiation and the neutron energies were determined by the cross section ratio of 90Zr (n,2n) 89Zr to 93Nb (n,2n) 92mNb reaction. The values of the cross sections of 232Th (n,f) 131m, gSn were analyzed, and the cross sections of 232Th (n,f) 131Sb were deduced to be 6.5± 0.7 , 6.3± 0.6 , 6.1± 0.6 mb at 14.1± 0.3 , 14.5± 0.3 and 14.8± 0.3 MeV, respectively. The values of the cross sections of 232Th (n,f) 131gTe were deduced to be 1.8± 0.1 , 1.5± 0.1 and 1.4± 0.1 mb at 14.1± 0.3 , 14.5± 0.3 and 14.8± 0.3 MeV, respectively. The values of the cross sections of 232Th (n,f) 131I were given as 1.8± 0.2 , 1.6± 0.2 , 1.5± 0.1 mb at 14.1± 0.3 , 14.5± 0.3 and 14.8± 0.3 MeV, respectively.

  18. Facial recognition of heroin vaccine opiates: type 1 cross-reactivities of antibodies induced by hydrolytically stable haptenic surrogates of heroin, 6-acetylmorphine, and morphine.

    PubMed

    Matyas, Gary R; Rice, Kenner C; Cheng, Kejun; Li, Fuying; Antoline, Joshua F G; Iyer, Malliga R; Jacobson, Arthur E; Mayorov, Alexander V; Beck, Zoltan; Torres, Oscar B; Alving, Carl R

    2014-03-14

    Novel synthetic compounds similar to heroin and its major active metabolites, 6-acetylmorphine and morphine, were examined as potential surrogate haptens for the ability to interface with the immune system for a heroin vaccine. Recent studies have suggested that heroin-like haptens must degrade hydrolytically to induce independent immune responses both to heroin and to the metabolites, resulting in antisera containing mixtures of antibodies (type 2 cross-reactivity). To test this concept, two unique hydrolytically stable haptens were created based on presumed structural facial similarities to heroin or to its active metabolites. After conjugation of a heroin-like hapten (DiAmHap) to tetanus toxoid and mixing with liposomes containing monophosphoryl lipid A, high titers of antibodies after two injections in mice had complementary binding sites that exhibited strong type 1 ("true") specific cross-reactivity with heroin and with both of its physiologically active metabolites. Mice immunized with each surrogate hapten exhibited reduced antinociceptive effects caused by injection of heroin. This approach obviates the need to create hydrolytically unstable synthetic heroin-like compounds to induce independent immune responses to heroin and its active metabolites for vaccine development. Facial recognition of hydrolytically stable surrogate haptens by antibodies together with type 1 cross-reactivities with heroin and its metabolites can help to guide synthetic chemical strategies for efficient development of a heroin vaccine. Copyright © 2014. Published by Elsevier Ltd.

  19. Effect of green tea extract on advanced glycation and cross-linking of tail tendon collagen in streptozotocin induced diabetic rats.

    PubMed

    Babu, Pon Velayutham Anandh; Sabitha, Kuruvimalai Ekambaram; Shyamaladevi, Chennam Srinivasulu

    2008-01-01

    Diabetes leads to modification of collagen such as advanced glycation and cross-linking which play an important role in the pathogenesis of diabetes mellitus. We have investigated the effect of green tea on modification of collagen in streptozotocin (60 mg/kg body weight) induced diabetic rats. To investigate the therapeutic effect of green tea, treatment was begun six weeks after the onset of diabetes and green tea extract (300 mg/kg body weight) was given orally for 4 weeks. The collagen content, extent of advanced glycation, advanced glycation end products (AGE) and cross-linking of tail tendon collagen were investigated. Green tea reduced the tail tendon collagen content which increased in diabetic rats. Accelerated advanced glycation and AGE in diabetic animals, as detected by Ehrlich's-positive material and collagen linked fluorescence respectively were reduced significantly by green tea. The solubility of tail tendon collagen decreased significantly in diabetic rats indicating a remarkable increase in the cross-linking, whereas green tea increases the solubility of collagen in diabetic rats. The present study reveals that green tea is effective in reducing the modification of tail tendon collagen in diabetic rats. Thus green tea may have a therapeutic effect in the treatment of glycation induced complications of diabetes.

  20. CEACAM6 cross-linking induces caveolin-1-dependent, Src-mediated focal adhesion kinase phosphorylation in BxPC3 pancreatic adenocarcinoma cells.

    PubMed

    Duxbury, Mark S; Ito, Hiromichi; Ashley, Stanley W; Whang, Edward E

    2004-05-28

    Despite lacking transmembrane or intracellular domains, glycosylphosphatidylinositol-anchored proteins can modulate intracellular signaling events, in many cases through aggregation within membrane "lipid raft" microdomains. CEACAM6 is a glycosylphosphatidylinositol-linked cell surface protein of importance in the anchorage-independent survival and metastasis of pancreatic adenocarcinoma cells. We examined the effects of antibody-mediated cross-linking of CEACAM6 on intracellular signaling events and anchorage-independent survival of the CEACAM6-overexpressing pancreatic ductal adenocarcinoma cell line, BxPC3. CEACAM6 cross-linking increased c-Src activation and induced tyrosine phosphorylation of p125(FAK) focal adhesion kinase. Focal adhesion kinase phosphorylation was dependent on c-Src kinase activation, for which caveolin-1 was required. CEACAM6 cross-linking induced a significant increase in cellular resistance to anoikis. These observations represent the first characterization of the mechanism through which this important cell surface oncoprotein influences intracellular signaling events and hence malignant cellular behavior.

  1. WRN Is Required for ATM Activation and the S-Phase Checkpoint in Response to Interstrand Cross-Link–Induced DNA Double-Strand Breaks

    PubMed Central

    Cheng, Wen-Hsing; Muftic, Diana; Muftuoglu, Meltem; Dawut, Lale; Morris, Christa; Helleday, Thomas; Shiloh, Yosef

    2008-01-01

    Werner syndrome (WS) is a human genetic disorder characterized by extensive clinical features of premature aging. Ataxia-telengiectasia (A-T) is a multisystem human genomic instability syndrome that includes premature aging in some of the patients. WRN and ATM, the proteins defective in WS and A-T, respectively, play significant roles in the maintenance of genomic stability and are involved in several DNA metabolic pathways. A role for WRN in DNA repair has been proposed; however, this study provides evidence that WRN is also involved in ATM pathway activation and in a S-phase checkpoint in cells exposed to DNA interstrand cross-link–induced double-strand breaks. Depletion of WRN in such cells by RNA interference results in an intra-S checkpoint defect, and interferes with activation of ATM as well as downstream phosphorylation of ATM target proteins. Treatment of cells under replication stress with the ATM kinase inhibitor KU 55933 results in a S-phase checkpoint defect similar to that observed in WRN shRNA cells. Moreover, γH2AX levels are higher in WRN shRNA cells than in control cells 6 and 16 h after exposure to psoralen DNA cross-links. These results suggest that WRN and ATM participate in a replication checkpoint response, in which WRN facilitates ATM activation in cells with psoralen DNA cross-link–induced collapsed replication forks. PMID:18596239

  2. Molecular mimicry between the rabies virus glycoprotein and human immunodeficiency virus-1 GP120: cross-reacting antibodies induced by rabies vaccination.

    PubMed

    Bracci, L; Ballas, S K; Spreafico, A; Neri, P

    1997-11-01

    The 160-170 sequence of human immunodeficiency virus (HIV)-1 gp120 mimics a nicotinic receptor-binding motif of rabies virus glycoprotein and snake neurotoxins. This sequence has been proposed to be involved in the binding of HIV-1 gp120 to the acetylcholine binding sites of nicotinic receptors. By using biomolecular interaction analysis (BIA) technology we have found that HIV-1 gp120 can bind to detergent-extracted nicotinic receptor from fetal calf muscle. The binding is inhibited by nicotine and by a synthetic peptide reproducing the gp120 160-170 sequence. The molecular mimicry between gp120 and rabies virus glycoprotein is confirmed by cross-reacting antibodies. We have found that vaccination against rabies can induce the production of anti-HIV-1 gp120 antibodies in humans. The cross-reacting antibodies are directed to the gp120 sequence involved in the mimicry with the rabies virus glycoprotein. The cross-reactivity between the rabies virus and HIV-1 has important implications in transfusion medicine. Moreover, the presence of cross-reacting antibodies between the nicotinic receptor binding site of rabies virus glycoprotein and a fragment of HIV-1 gp120 strengthens the hypothesis about the possible role of nicotinic receptors as potential receptors for HIV-1 in the central nervous system.

  3. Measurements of proton induced γ-ray emission cross-sections on Mg from 1.0 to 3.0 MeV

    NASA Astrophysics Data System (ADS)

    Sharifzadeh, N.; Kakuee, O.; Mohammadi, S.

    2016-04-01

    Differential cross-section of proton induced γ-ray emission from the reactions 24Mg(p,p‧γ)24Mg (Eγ = 1369 keV), 25Mg(p,p‧γ)25Mg (Eγ = 390, 585, 975 keV) and 26Mg(p,γ)27Al (Eγ = 1014 keV) were measured for proton energies from 1 to 3 MeV using a 60 μg/cm2 Mg target evaporated on a 40 μg/cm2 Ag thin film. The γ-rays were collected by a 50% relative efficiency HPGe detector placed at an angle of 90° with respect to the beam direction, while the backscattered protons were collected by an ion implanted Si detector placed at a scattering angle of 165°. Simultaneous collection of γ-ray and RBS spectra is a great advantage of this approach which makes differential cross-section measurements independent on the collected beam charge. Measured cross-section values were compared with the previously reported data in the literature. Absolute γ-ray differential cross-sections were obtained with an overall systematic uncertainty of about ±6% and statistical uncertainty of less than ±5% for proton energies higher than 2.24 MeV.

  4. On fatigue damage accumulation from in-line and cross-flow vortex-induced vibrations on risers

    NASA Astrophysics Data System (ADS)

    Baarholm, G. S.; Larsen, C. M.; Lie, H.

    2006-01-01

    Large-scale model tests of a tensioned steel riser were performed at Hanøytangen outside Bergen, Norway in 1997. The length of the model was 90 m and the diameter was 3 cm. The information from these tests consists of measured bending strains, tension, flow speed and all relevant riser data. In this work, this information is reexamined in an attempt to improve our understanding of vortex-induced vibrations (VIV) for cases with very high order of responding modes. The aim is in particular to study the relative importance of in-line (IL) and cross-flow (CF) vibrations for fatigue damage accumulation. It is shown that fatigue damage is proportional to U (U is the flow velocity) when the modes are dominated by tension. When bending controls the modes, the fatigue damage is proportional to U. A linear SN-curve with slope parameter m=3 is used. The Hanøytangen riser fatigue damage goes as U7 for the lowest velocities and U4 for the highest current velocities. Based on the Hanøytangen data, it seems that the transition velocity between the tension and the bending-stiffness-dominated regions is at the current velocity that gives response at a mode number where a tensioned string and an untensioned beam have equal eigenfrequencies. IL response has a significant contribution to fatigue for cases dominated by the lowest modes. The reason is that IL oscillations will take place at double the frequency of those in CF. For a tension-controlled case, this corresponds to a mode with half the wavelength, while a bending-controlled case will tend to have a wavelength ratio of 2. Since the curvature for a given amplitude increases with the inverse modal wavelength squared, fatigue from IL tends to dominate for cases with tension-controlled modes (low current speed), while CF will dominate for bending-controlled modes (high current speed). This tendency is clearly seen in the experimental data for both CF and IL responses. Fatigue damage is calculated directly from the measured

  5. Neutron-induced fission cross section of 242Pu from 15 MeV to 20 MeV

    NASA Astrophysics Data System (ADS)

    Jovančević, N.; Salvador-Castineira, P.; Daraban, L.; Vidali, M.; Heyse, J.; Oberstedt, S.; Hambsch, F.-J.; Bonaldi, C.; Geerts, W.

    2017-09-01

    Accurate nuclear-data needs in the fast-neutron-energy region have been recently addressed for the development of next generation nuclear power plants (GEN-IV) by the OECD Nuclear Energy Agency (NEA). This sensitivity study has shown that of particular interest is the 242Pu(n,f) cross section for fast reactor systems. Measurements have been performed with quasi-monoenergetic neutrons in the energy range from 15 MeV to 20 MeV produced by the Van de Graaff accelerator of the JRC-Geel. A twin Frisch-grid ionization chamber has been used in a back-to-back configuration as fission fragment detector. The 242Pu(n,f) cross section has been normalized to 238U(n,f) cross section data. The results were compared with existing literature data and show acceptable agreement within 5%.

  6. Induced abortion and effecting factors of ever married women in the Southeast Anatolian Project Region, Turkey: a cross sectional study

    PubMed Central

    Bozkurt, Ali Ihsan; Özcirpici, Birgul; Ozgur, Servet; Sahinoz, Saime; Sahinoz, Turgut; Saka, Gunay; Ceylan, Ali; Ilcin, Ersen; Acemoglu, Hamit; Palanci, Yilmaz; Akkafa, Feridun; Ak, Mucide

    2004-01-01

    Background Nearly 10% of the population of Turkey lives in the Southeast Anatolian Project (SEAP) region. The population growth rate and the rate of unintended pregnancies are high and family planning services are insufficient in this region. Lifetime induced abortion rate is also high in this region. Public health problems of the SEAP region were investigated in the "SEAP Public Health Project" in 2001 and 2002. As it is one of the most important health problems of the women living in this region; induced abortion was also investigated in this project. Methods An optimumsample size representing the rural and urban area of the region (n = 1150) was chosen by the State Institute of Statistics by a sampling method proportional to size. 1126 of the area's 1150 houses have been visited and data about induced abortions have been obtained by applying a questionnaire to 1491 ever married women who live in the region. Results It has been found that 9.0% of these women who had at least one pregnancy in their life had at least one induced abortion. The lifetime induced abortion per 100 pregnancies was found to be 2.45. The primary reason given for induced abortions was "wanting no more children" (64.6%). Lifetime induced abortions were 5.3 times greater with women using a family planning method than women not using family planning methods. Lifetime induced abortions were 4.1 times greater with unemployed women than working women. Most of the women have used private doctors in order to have an induced abortion. Although 32.29% have not yet begun to use a contraceptive method after their last induced abortion, 43.75% of the women have since started to use an effective contraceptive method. 23.96% of them have begun to use an ineffective contraceptive method. Conclusions Induced abortion is still an important problem at the SEAP region. The results of the study remind us that unemployed women and women who have more than four children is our target group in the campaign against

  7. Activation cross-sections of long lived products of deuteron induced nuclear reactions on dysprosium up to 50 MeV.

    PubMed

    Tárkányi, F; Ditrói, F; Takács, S; Csikai, J; Hermanne, A; Ignatyuk, A V

    2014-01-01

    Activation cross-sections for production of (162m,161,155)Ho, (165,159,157,155)Dy and (161,160,156,155)Tb radionuclides in deuteron induced nuclear reactions on elemental dysprosium were measured up to 50 MeV for practical application and the test of the predictive power of nuclear reaction model codes. A stacked-foil irradiation technique and off-line gamma-ray spectrometry were used to determine the activities. No earlier cross-section data were found in the literature. The experimental data are compared with the predictions of the ALICE-D, EMPIRE-D and TALYS codes. Integral production yields were calculated from the fitted experimental data.

  8. Measuring the cross sections of heavy-metal spallation induced by deuterons with energies of 2, 2.94, and 3.5 GeV per nucleon

    NASA Astrophysics Data System (ADS)

    Artyushenko, M. Yu.; Baldin, A. A.; Berlev, A. I.; Bukhal, O. V.; Voronko, V. A.; Gusak, K. V.; Zhuk, I. V.; Kudashkin, I. V.; Paraipan, M.; Potapenko, A. S.; Safronova, A. A.; Sotnikov, V. V.; Tyutyunnikov, S. I.

    2016-07-01

    The cross sections for the spallation of the heavy-metal nuclei 181Ta, 197Au, 207Pb, 209Bi, 232Th, and 238U induced by relativistic deuterons with energies of 2, 2.94, and 3.5 GeV per nucleon are measured using the deuteron beam from the Nuclotron accelerator of the JINR Laboratory of High Energy Physics in Dubna, Russia. The cross-section measurements employ a combined experimental technique involving the solidstate nuclear-track detectors and the activation gamma spectrometry. Adding our measurements to the database of experimental nuclear data will make it possible to test the computer codes used for selecting the parameters of the ADS-type facilities.

  9. Cross section measurement of residues produced in proton- and deuteron-induced spallation reactions on 93Zr at 105 MeV/u using the inverse kinematics method

    NASA Astrophysics Data System (ADS)

    Kawase, Shoichiro; Watanabe, Yukinobu; Wang, He; Otsu, Hideaki; Sakurai, Hiroyoshi; Takeuchi, Satoshi; Togano, Yasuhiro; Nakamura, Takashi; Maeda, Yukie; Ahn, Deuk Soon; Aikawa, Masayuki; Araki, Shouhei; Chen, Sidong; Chiga, Nobuyuki; Doornenbal, Pieter; Fukuda, Naoki; Ichihara, Takashi; Isobe, Tadaaki; Kawakami, Shunsuke; Kin, Tadahiro; Kondo, Yosuke; Koyama, Shunpei; Kubo, Toshiyuki; Kubono, Shigeru; Kurokawa, Meiko; Makinaga, Ayano; Matsushita, Masafumi; Matsuzaki, Teiichiro; Michimasa, Shin'ichiro; Momiyama, Satoru; Nagamine, Shunsuke; Nakano, Keita; Niikura, Megumi; Ozaki, Tomoyuki; Saito, Atsumi; Saito, Takeshi; Shiga, Yoshiaki; Shikata, Mizuki; Shimizu, Yohei; Shimoura, Susumu; Sumikama, Toshiyuki; Söderström, Pär-Anders; Suzuki, Hiroshi; Takeda, Hiroyuki; Taniuchi, Ryo; Tsubota, Jun'ichi; Watanabe, Yasushi; Wimmer, Kathrin; Yamamoto, Tatsuya; Yoshida, Koichi

    2017-09-01

    Isotopic production cross sections in the proton- and deuteron-induced spallation reactions on 93Zr at an energy of 105 MeV/u were measured in inverse kinematics conditions for the development of realistic nuclear transmutation processes for long-lived fission products (LLFPs) with neutron and light-ion beams. The experimental results were compared to the PHITS calculations describing the intra-nuclear cascade and evaporation processes. Although an overall agreement was obtained, a large overestimation of the production cross sections for the removal of a few nucleons was seen. A clear shell effect associated with the neutron magic number N = 50 was observed in the measured isotopic production yields of Zr and Y isotopes, which can be reproduced reasonably by the PHITS calculation.

  10. Measurement of the neutron-induced fission cross-section of 241Am at the time-of-flight facility n_TOF

    NASA Astrophysics Data System (ADS)

    Belloni, F.; Calviani, M.; Colonna, N.; Mastinu, P.; Milazzo, P. M.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Audouin, L.; Badurek, G.; Barbagallo, M.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Käppeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martínez, T.; Massimi, C.; Meaze, M. H.; Mengoni, A.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tarrio, D.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K.

    2013-01-01

    The neutron-induced fission cross-section of 241Am has been measured relative to the standard fission cross-section of 235U between 0.5 and 20MeV. The experiment was performed at the CERN n_TOF facility. Fission fragments were detected by a fast ionization chamber by discriminating against the α-particles from the high radioactivity of the samples. The high instantaneous neutron flux and the low background of the n_TOF facility enabled us to obtain uncertainties of ≈ 5%. With the present results it was possible to resolve discrepancies between previous data sets and to confirm current evaluations, thus providing important information for design studies of future reactors with improved fuel burn-up.

  11. Distribution of Young's Modulus in Porcine Corneas after Riboflavin/UVA-Induced Collagen Cross-Linking as Measured by Atomic Force Microscopy

    PubMed Central

    Rheinlaender, Johannes; Sel, Saadettin; Scholz, Michael; Paulsen, Friedrich; Schäffer, Tilman E.

    2014-01-01

    Riboflavin/UVA-induced corneal collagen cross-linking has become an effective clinical application to treat keratoconus and other ectatic disorders of the cornea. Its beneficial effects are attributed to a marked stiffening of the unphysiologically weak stroma. Previous studies located the stiffening effect predominantly within the anterior cornea. In this study, we present an atomic force microscopy-derived analysis of the depth-dependent distribution of the Young's modulus with a depth resolution of 5 µm in 8 cross-linked porcine corneas and 8 contralateral controls. Sagittal cryosections were fabricated from every specimen and subjected to force mapping. The mean stromal depth of the zone with effective cross-linking was found to be 219±67 µm. Within this cross-linked zone, the mean Young's modulus declined from 49±18 kPa at the corneal surface to 46±17 kPa, 33±11 kPa, 17±5 kPa, 10±4 kPa and 10±4 kPa at stromal depth intervals of 0–50 µm, 50–100 µm, 100–150 µm, 150–200 µm and 200–250 µm, respectively. This corresponded to a stiffening by a factor of 8.1 (corneal surface), 7.6 (0–50 µm), 5.4 (50–100 µm), 3.0 (100–150 µm), 1.6 (150–200 µm), and 1.5 (200–250 µm), when compared to the Young's modulus of the posterior 100 µm. The mean Young's modulus within the cross-linked zone was 20±8 kPa (2.9-fold stiffening), while it was 11±4 kPa (1.7-fold stiffening) for the entire stroma. Both values were significantly distinct from the mean Young's modulus obtained from the posterior 100 µm of the cross-linked corneas and from the contralateral controls. In conclusion, we were able to specify the depth-dependent distribution of the stiffening effect elicited by standard collagen cross-linking in porcine corneas. Apart from determining the depth of the zone with effective corneal cross-linking, we also developed a method that allows for atomic force microscopy-based measurements of gradients of Young's modulus in soft tissues in

  12. The human oxidative DNA glycosylase NEIL1 excises psoralen-induced interstrand DNA cross-links in a three-stranded DNA structure.

    PubMed

    Couvé, Sophie; Macé-Aimé, Gaëtane; Rosselli, Filippo; Saparbaev, Murat K

    2009-05-01

    Previously, we have demonstrated that human oxidative DNA glycosylase NEIL1 excises photoactivated psoralen-induced monoadducts but not genuine interstrand cross-links (ICLs) in duplex DNA. It has been postulated that the repair of ICLs in mammalian cells is mainly linked to DNA replication and proceeds via dual incisions in one DNA strand that bracket the cross-linked site. This process, known as "unhooking," enables strand separation and translesion DNA synthesis through the gap, yielding a three-stranded DNA repair intermediate composed of a short unhooked oligomer covalently bound to the duplex. At present, the detailed molecular mechanism of ICL repair in mammalian cells remains unclear. Here, we constructed and characterized three-stranded DNA structures containing a single ICL as substrates for the base excision repair proteins. We show that NEIL1 excises with high efficiency the unhooked ICL fragment within a three-stranded DNA structure. Complete reconstitution of the repair of unhooked ICL shows that it can be processed in a short patch base excision repair pathway. The new substrate specificity of NEIL1 points to a preferential involvement in the replication-associated repair of ICLs. Based on these data, we propose a model for the mechanism of ICL repair in mammalian cells that implicates the DNA glycosylase activity of NEIL1 downstream of Xeroderma Pigmentosum group F/Excision Repair Cross-Complementing 1 endonuclease complex (XPF/ERCC1) and translesion DNA synthesis repair steps. Finally, our data demonstrate that Nei-like proteins from Escherichia coli to human cells can excise bulky unhooked psoralen-induced ICLs via hydrolysis of glycosidic bond between cross-linked base and deoxyribose sugar, thus providing an alternative heuristic solution for the removal of complex DNA lesions.

  13. Rationally Designed Vaccines Targeting the V2 Region of HIV-1 gp120 Induce a Focused, Cross-Clade-Reactive, Biologically Functional Antibody Response.

    PubMed

    Zolla-Pazner, Susan; Powell, Rebecca; Yahyaei, Sara; Williams, Constance; Jiang, Xunqing; Li, Wei; Lu, Shan; Wang, Shixia; Upadhyay, Chitra; Hioe, Catarina E; Totrov, Max; Kong, Xiangpeng

    2016-12-15

    Strong antibody (Ab) responses against V1V2 epitopes of the human immunodeficiency virus type 1 (HIV-1) gp120 envelope (Env) correlated with reduced infection rates in studies of HIV, simian-human immunodeficiency virus (SHIV), and simian immunodeficiency virus (SIV). In order to focus the Ab response on V1V2, we used six V1V2 sequences and nine scaffold proteins to construct immunogens which were tested using various immunization regimens for their ability to induce cross-reactive and biologically active V2 Abs in rabbits. A prime/boost immunization strategy was employed using gp120 DNA and various V1V2-scaffold proteins. The rabbit polyclonal Ab responses (i) were successfully focused on the V1V2 region, with weak or only transient responses to other Env epitopes, (ii) displayed broad cross-reactive binding activity with gp120s and the V1V2 regions of diverse strains from clades B, C, and E, (iii) included V2 Abs with specificities similar to those found in HIV-infected individuals, and (iv) remained detectable ≥1 year after the last boosting dose. Importantly, sera from rabbits receiving V1V2-scaffold immunogens displayed Ab-dependent cellular phagocytosis whereas sera from rabbits receiving only gp120 did not. The results represent the first fully successful example of reverse vaccinology in the HIV vaccine field with rationally designed epitope scaffold immunogens inducing Abs that recapitulate the epitope specificity and biologic activity of the human monoclonal Abs from which the immunogens were designed. Moreover, this is the first immunogenicity study using epitope-targeting, rationally designed vaccine constructs that induced an Fc-mediated activity associated with protection from infection with HIV, SIV, and SHIV. Novel immunogens were designed to focus the antibody response of rabbits on the V1V2 epitopes of HIV-1 gp120 since such antibodies were associated with reduced infection rates of HIV, SIV, and SHIV. The vaccine-induced antibodies were broadly

  14. Lack of transient receptor potential vanilloid 1 channel modulates the development of neurogenic bladder dysfunction induced by cross-sensitization in afferent pathways

    PubMed Central

    2013-01-01

    Background Bladder pain of unknown etiology has been associated with co-morbid conditions and functional abnormalities in neighboring pelvic organs. Mechanisms underlying pain co-morbidities include cross-sensitization, which occurs predominantly via convergent neural pathways connecting distinct pelvic organs. Our previous results showed that colonic inflammation caused detrusor instability via activation of transient receptor potential vanilloid 1 (TRPV1) signaling pathways, therefore, we aimed to determine whether neurogenic bladder dysfunction can develop in the absence of TRPV1 receptors. Methods Adult male C57BL/6 wild-type (WT) and TRPV1−/− (knockout) mice were used in this study. Colonic inflammation was induced by intracolonic trinitrobenzene sulfonic acid (TNBS). The effects of transient colitis on abdominal sensitivity and function of the urinary bladder were evaluated by cystometry, contractility and relaxation of detrusor smooth muscle (DSM) in vitro to various stimuli, gene and protein expression of voltage-gated sodium channels in bladder sensory neurons, and pelvic responses to mechanical stimulation. Results Knockout of TRPV1 gene did not eliminate the development of cross-sensitization between the colon and urinary bladder. However, TRPV1−/− mice had prolonged intermicturition interval and increased number of non-voiding contractions at baseline followed by reduced urodynamic responses during active colitis. Contractility of DSM was up-regulated in response to KCl in TRPV1−/− mice with inflamed colon. Application of Rho-kinase inhibitor caused relaxation of DSM in WT but not in TRPV1−/− mice during colonic inflammation. TRPV1−/− mice demonstrated blunted effects of TNBS-induced colitis on expression and function of voltage-gated sodium channels in bladder sensory neurons, and delayed development of abdominal hypersensitivity upon colon-bladder cross-talk in genetically modified animals. Conclusions The lack of TRPV1 receptors

  15. Mass Spectrometry Based Proteomics Study of Cisplatin-Induced DNA-Protein Cross-Linking in Human Fibrosarcoma (HT1080) Cells.

    PubMed

    Ming, Xun; Groehler, Arnold; Michaelson-Richie, Erin D; Villalta, Peter W; Campbell, Colin; Tretyakova, Natalia Y

    2017-04-17

    Platinum-based antitumor drugs such as 1,1,2,2-cis-diamminedichloroplatinum(II) (cisplatin), carboplatin, and oxaliplatin are currently used to treat nearly 50% of all cancer cases, and novel platinum based agents are under development. The antitumor effects of cisplatin and other platinum compounds are attributed to their ability to induce interstrand DNA-DNA cross-links, which are thought to inhibit tumor cell growth by blocking DNA replication and/or preventing transcription. However, platinum agents also induce significant numbers of unusually bulky and helix-distorting DNA-protein cross-links (DPCs), which are poorly characterized because of their unusual complexity. We and others have previously shown that DPCs block DNA replication and transcription and causes toxicity in human cells, potentially contributing to the biological effects of platinum agents. In the present work, we have undertaken a system-wide investigation of cisplatin-mediated DNA-protein cross-linking in human fibrosarcoma (HT1080) cells using mass spectrometry-based proteomics. DPCs were isolated from cisplatin-treated cells using a modified phenol/chloroform DNA extraction in the presence of protease inhibitors. Proteins were released from DNA strands and identified by mass spectrometry-based proteomics and immunological detection. Over 250 nuclear proteins captured on chromosomal DNA following treatment with cisplatin were identified, including high mobility group (HMG) proteins, histone proteins, and elongation factors. To reveal the exact molecular structures of cisplatin-mediated DPCs, isotope dilution HPLC-ESI(+)-MS/MS was employed to detect 1,1-cis-diammine-2-(5-amino-5-carboxypentyl)amino-2-(2'-deoxyguanosine-7-yl)-platinum(II) (dG-Pt-Lys) conjugates between the N7 guanine of DNA and the ε-amino group of lysine. Our results demonstrate that therapeutic levels of cisplatin induce a wide range of DPC lesions, which likely contribute to both target and off target effects of this

  16. Neutralizing and cross-neutralizing antibody titres induced by bivalent and quadrivalent human papillomavirus vaccines in the target population of organized vaccination programmes.

    PubMed

    Barzon, Luisa; Squarzon, Laura; Masiero, Serena; Pacenti, Monia; Marcati, Giorgia; Mantelli, Barbara; Gabrielli, Liliana; Pascucci, Maria Grazia; Lazzarotto, Tiziana; Caputo, Antonella; Palù, Giorgio

    2014-09-15

    Aim of this investigator-initiated study was to evaluate and compare the titres of neutralizing and cross-neutralizing antibodies (NAbs) induced by the bivalent (Cervarix(®)) and quadrivalent (Gardasil(®)) HPV vaccines in a cohort of girls aged 11-13 years from organized vaccination programmes. To this aim, HPV16 and HPV18 NAbs were measured by pseudovirion-based neutralization assays in serum collected at 1-6 months after the third vaccine dose in 107 girls vaccinated with Cervarix(®) and 126 vaccinated with Gardasil(®), while HPV31 and HPV45 cross-NAbs were tested in the first 50 consecutive girls of both vaccine groups. The results of this study demonstrated that all vaccinated girls developed HPV16 and HPV18 NAbs, with the exception of two Gardasil(®) vaccinees with undetectable HPV18 NAbs. Geometric mean titres (GMTs) of both HPV16 and HPV18 NAbs were significantly higher in Cervarix(®) than in Gardasil(®) vaccinees [HPV16 NAb GMT 22,136 (95% CI, 18,811-26,073) vs 5092 (4230-6151), respectively; P<0.0001; HPV18 NAb GMT 11,962 (9536-14,363) vs 1804 (1574-2110), respectively; P<0.0001]. Cross-NAbs to HPV31 and HPV45 were detected more frequently Cervarix(®) (HPV31 NAb positivity rates 92.7% and 36%, respectively; P<0.05) than in Gardasil(®) vaccinees (HPV45 NAb positivity rates 56% and 6%, respectively; P<0.0001). The titres of cross-NAbs against HPV31 and HPV45 were also significantly higher in Cervarix(®) than in Gardasil(®) vaccinees [HPV31 NAb GMT 157.2 (95% CI, 92-269) vs 13.0 (6.5-25.8), respectively; P<0.0001; HPV45 NAb GMT 4.7 (2.1-10.2) vs 1.3 (0.3-3.1), respectively; P<0.01]. In conclusion, in adolescent girls vaccinated within organized vaccination programmes, HPV vaccines drive the generation not only of NAbs to HPV vaccine types, but also of cross-NAbs. The bivalent vaccine induced significantly higher HPV16 and HPV18 NAb titres and more frequently and at higher titre HPV31 and HPV45 cross-NAbs than the quadrivalent vaccine. Copyright

  17. Double differential cross section for light mass fragment production on tens of MeV proton, deuteron, helium and carbon induced reactions

    NASA Astrophysics Data System (ADS)

    Sanami, Toshiya; Yamaguchi, Yuji; Uozumi, Yusuke; Hagiwara, Masayuki; Koba, Yusuke

    2017-09-01

    Double differential cross sections (DDXs) of light mass fragment (LMFs - Li,Be,B,C,N and O) productions were measured for tens of MeV proton, deuteron helium and carbon induced reactions on Be, C, Al, Ti and Cu targets. The incident energies for the measurements were chosen to allow us to compare DDXs with same incident energy but different projectiles on various targets. Systematic data were obtained to see the differences between projectile energies, particles, targets and emitted particles. From the comparison, reaction processes of not only evaporation from complete fusion nucleus, but also scattering, pickup, stripping and projectile fragmentation were observed.

  18. Calculated neutron-induced cross sections for /sup 58,60/Ni from 1 to 20 MeV and comparisons with experiments

    SciTech Connect

    Hetrick, D.M.; Fu, C.Y.; Larson, D.C.

    1987-06-01

    Nuclear model codes were used to compute cross sections for neutron-induced reactions on both /sup 58/Ni and /sup 60/Ni for incident energies from 1 to 20 MeV. The input parameters for the model codes were determined through analysis of experimental data in this energy region. Discussion of the models used, the input data, the resulting calculations, extensive comparisons to measured data, and comparisons to the Evaluated Nuclear Data File (ENDF/B-V) for Ni (MAT 1328) are included in this report. 118 refs., 101 figs., 19 tabs.

  19. Thermal neutron cross-section and resonance integral of the 152Sm(n,γ)153Sm reaction induced by pulsed neutrons

    NASA Astrophysics Data System (ADS)

    Van Do, Nguyen; Khue, Pham Duc; Thanh, Kim Tien; Hien, Nguyen Thi; Kim, Guinyun; Kim, Kwangsoo; Shin, Sung-Gyun; Kye, Yong-Uk; Cho, Moo-Hyun

    2017-10-01

    We measured the thermal neutron cross-section (σ0) and resonance integral (I0) of the 152Sm(n,γ)153Sm reaction relative to that of the 197Au(n,γ)198Au reaction. Sm and Au foils with and without a cadmium cover of 0.5 mm were irradiated with moderated pulsed neutrons produced from the electron linac. The induced activities of the reaction products were determined via high energy resolution HPGe detector. The present results: σ0,Sm =212±8 b and I0,Sm =3.02±0.19 kb are consistent with most of the existing reference data.

  20. Comparison of the cross-antibody response induced in sheep by inactivated bovine viral diarrhoea virus 1 and Hobi-like pestivirus.

    PubMed

    Decaro, Nicola; Mari, Viviana; Sciarretta, Rossana; Lucente, Maria Stella; Camero, Michele; Losurdo, Michele; Larocca, Vittorio; Colao, Valeriana; Cavaliere, Nicola; Lovero, Angela; Lorusso, Eleonora; Buonavoglia, Canio

    2013-06-01

    Hobi-like pestivirus, a new tentative species within genus Pestivirus, was firstly detected in foetal bovine serum batches and later associated to respiratory distress and reproductive failures in cattle. In the present study, the cross-antibody response between bovine viral diarrhoea virus 1 (BVDV-1) and the emerging pestivirus was evaluated in the sheep model. Ten sheep were immunised against BVDV-1 or Hobi-like pestivirus using inactivated preparations and the induced antibody responses were evaluated against the homologous and heterologous viruses. The results showed that heterologous antibody titres were significantly lower than the homologous ones, thus suggesting the need to develop specific vaccines against the emerging pestiviral species.

  1. Measurement of the neutron-induced fission cross-section of 243Am relative to 235U from 0.5 to 20 MeV

    NASA Astrophysics Data System (ADS)

    Belloni, F.; Calviani, M.; Colonna, N.; Mastinu, P.; Milazzo, P. M.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Audouin, L.; Badurek, G.; Barbagallo, M.; Baumann, P.; Bečvář, F.; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Käppeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Kerveno, M.; Koehler, P.; Kossionides, E.; Krtička, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martínez, T.; Massimi, C.; Meaze, M. H.; Mengoni, A.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tarrio, D.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K.

    2011-12-01

    The ratio of the neutron-induced fission cross-sections of 243Am and 235U was measured in the energy range from 0.5 to 20 MeV with uncertainties of ≈ 4%. The experiment was performed at the CERN n_TOF facility using a fast ionization chamber. With the good counting statistics that could be achieved thanks to the high instantaneous flux and the low backgrounds, the present results are useful for resolving discrepancies in previous data sets and are important for future reactors with improved fuel burn-up.

  2. Calculated neutron-induced cross sections for /sup 52/Cr from 1 to 20 MeV and comparisons with experiments

    SciTech Connect

    Hetrick, D.M.; Fu, C.Y.; Larson, D.C.

    1987-09-15

    Nuclear model codes were used to compute cross sections for neutron-induced reactions on /sup 52/Cr for incident energies from 1 to 20 MeV. The input parameters for the model codes were determined through analysis of experimental data in this energy region. Discussion of the models used, the input data, the resulting calculations, extensive comparisons to measured data, and comparisons to the Evaluated Nuclear Data File (ENDF/B-V) for Cr (MAT 1324) are included in this report. 103 refs., 67 figs., 12 tabs.

  3. Previous induced abortion among young women seeking abortion-related care in Kenya: a cross-sectional analysis.

    PubMed

    Kabiru, Caroline W; Ushie, Boniface A; Mutua, Michael M; Izugbara, Chimaraoke O

    2016-05-14

    Unsafe abortion is a leading cause of death among young women aged 10-24 years in sub-Saharan Africa. Although having multiple induced abortions may exacerbate the risk for poor health outcomes, there has been minimal research on young women in this region who have multiple induced abortions. The objective of this study was therefore to assess the prevalence and correlates of reporting a previous induced abortion among young females aged 12-24 years seeking abortion-related care in Kenya. We used data on 1,378 young women aged 12-24 years who presented for abortion-related care in 246 health facilities in a nationwide survey conducted in 2012. Socio-demographic characteristics, reproductive and clinical histories, and physical examination assessment data were collected from women during a one-month data collection period using an abortion case capture form. Nine percent (n = 98) of young women reported a previous induced abortion prior to the index pregnancy for which they were receiving care. Statistically significant differences by previous history of induced abortion were observed for area of residence, religion and occupation at bivariate level. Urban dwellers and unemployed/other young women were more likely to report a previous induced abortion. A greater proportion of young women reporting a previous induced abortion stated that they were using a contraceptive method at the time of the index pregnancy (47 %) compared with those reporting no previous induced abortion (23 %). Not surprisingly, a greater proportion of young women reporting a previous induced abortion (82 %) reported their index pregnancy as unintended (not wanted at all or mistimed) compared with women reporting no previous induced abortion (64 %). Our study results show that about one in every ten young women seeking abortion-related care in Kenya reports a previous induced abortion. Comprehensive post-abortion care services targeting young women are needed. In particular, post

  4. Hydralazine inhibits rapid acrolein-induced protein oligomerization: role of aldehyde scavenging and adduct trapping in cross-link blocking and cytoprotection.

    PubMed

    Burcham, Philip C; Pyke, Simon M

    2006-03-01

    Hydralazine strongly suppresses the toxicity of acrolein, a reactive aldehyde that contributes to numerous health disorders. At least two mechanisms may underlie the cytoprotection, both of which involve the nucleophilic hydrazine possessed by hydralazine. Under the simplest scenario, hydralazine directly scavenges free acrolein, decreasing intracellular acrolein availability and thereby suppressing macromolecular adduction. In a second "adduct-trapping" mechanism, the drug forms hydrazones with acrolein-derived Michael adducts in cell proteins, preventing secondary reactions of adducted proteins that may trigger cell death. To identify the most important mechanism, we explored these two pathways in mouse hepatocytes poisoned with the acrolein precursor allyl alcohol. Intense concentration-dependent adduct-trapping in cell proteins accompanied the suppression of toxicity by hydralazine. However, protective concentrations of hydralazine did not alter extracellular free acrolein levels, cellular glutathione loss, or protein carbonylation, suggesting that the cytoprotection is not due to minimization of intracellular acrolein availability. To explore ways whereby adduct-trapping might confer cytoprotection, the effect of hydralazine on acrolein-induced protein cross-linking was examined. Using bovine pancreas ribonuclease A as a model protein, acrolein caused rapid time- and concentration-dependent cross-linking, with dimerized protein detectable within 45 min of commencing protein modification. Lysine adduction in monomeric protein preceded the appearance of oligomers, whereas reductive methylation of protein amine groups abolished both adduction and oligomerization. Hydralazine inhibited cross-linking if added 30 min after commencing acrolein exposure but was ineffective if added after a 90-min delay. Adduct-trapping closely accompanied the inhibition of cross-linking by hydralazine. These findings suggest that cross-link blocking may contribute to hydralazine

  5. Advanced glycation end products induce in vitro cross-linking of alpha-synuclein and accelerate the process of intracellular inclusion body formation.

    PubMed

    Shaikh, Shamim; Nicholson, Louise F B

    2008-07-01

    Cross-linking of alpha-synuclein and Lewy body formation have been implicated in the dopaminergic neuronal cell death observed in Parkinson's disease (PD); the mechanisms responsible, however, are not clear. Reactive oxygen species and advanced glycation end products (AGEs) have been found in the intracellular, alpha-synuclein-positive Lewy bodies in the brains of both PD as well as incidental Lewy body disease patients, suggesting a role for AGEs in alpha-synuclein cross-linking and Lewy body formation. The aims of the present study were to determine 1) whether AGEs can induce cross-linking of alpha-synuclein peptides, 2) the progressive and time-dependent intracellular accumulation of AGEs and inclusion body formation, and 3) the effects of extracellular or exogenous AGEs on intracellular inclusion formation. We first investigated the time-dependent cross-linking of recombinant human alpha-synuclein in the presence of AGEs in vitro, then used a cell culture model based on chronic rotenone treatment of human dopaminergic neuroblastoma cells (SH-SY5Y) over a period of 1-4 weeks, in the presence of different doses of AGEs. Cells (grown on coverslips) and cell lysates, collected at the end of every week, were analyzed for the presence of intracellular reactive oxygen species, AGEs, alpha-synuclein proteins, and intracellular alpha-synuclein- and AGE-positive inclusion bodies by using immunocytochemical, biochemical, and Western blot techniques. Our results show that AGEs promote in vitro cross-linking of alpha-synuclein, that intracellular accumulation of AGEs precedes alpha-synuclein-positive inclusion body formation, and that extracellular AGEs accelerate the process of intracellular alpha-synuclein-positive inclusion body formation.

  6. rBCG30-Induced Immunity and Cross-Protection against Mycobacterium leprae Challenge Are Enhanced by Boosting with the Mycobacterium tuberculosis 30-Kilodalton Antigen 85B

    PubMed Central

    Gillis, Thomas P.; Tullius, Michael V.

    2014-01-01

    Leprosy remains a major global health problem and typically occurs in regions in which tuberculosis is endemic. Vaccines are needed that protect against both infections and do so better than the suboptimal Mycobacterium bovis BCG vaccine. Here, we evaluated rBCG30, a vaccine previously demonstrated to induce protection superior to that of BCG against Mycobacterium tuberculosis and Mycobacterium bovis challenge in animal models, for efficacy against Mycobacterium leprae challenge in a murine model of leprosy. rBCG30 overexpresses the M. tuberculosis 30-kDa major secretory protein antigen 85B, which is 85% homologous with the M. leprae homolog (r30ML). Mice were sham immunized or immunized intradermally with BCG or rBCG30 and challenged 2.5 months later by injection of viable M. leprae into each hind footpad. After 7 months, vaccine efficacy was assessed by enumerating the M. leprae bacteria per footpad. Both BCG and rBCG30 induced significant protection against M. leprae challenge. In the one experiment in which a comparison between BCG and rBCG30 was feasible, rBCG30 induced significantly greater protection than did BCG. Immunization of mice with purified M. tuberculosis or M. leprae antigen 85B also induced protection against M. leprae challenge but less so than BCG or rBCG30. Notably, boosting rBCG30 with M. tuberculosis antigen 85B significantly enhanced r30ML-specific immune responses, substantially more so than boosting BCG, and significantly augmented protection against M. leprae challenge. Thus, rBCG30, a vaccine that induces improved protection against M. tuberculosis, induces cross-protection against M. leprae that is comparable or potentially superior to that induced by BCG, and boosting rBCG30 with antigen 85B further enhances immune responses and protective efficacy. PMID:25001602

  7. rBCG30-induced immunity and cross-protection against Mycobacterium leprae challenge are enhanced by boosting with the Mycobacterium tuberculosis 30-kilodalton antigen 85B.

    PubMed

    Gillis, Thomas P; Tullius, Michael V; Horwitz, Marcus A

    2014-09-01

    Leprosy remains a major global health problem and typically occurs in regions in which tuberculosis is endemic. Vaccines are needed that protect against both infections and do so better than the suboptimal Mycobacterium bovis BCG vaccine. Here, we evaluated rBCG30, a vaccine previously demonstrated to induce protection superior to that of BCG against Mycobacterium tuberculosis and Mycobacterium bovis challenge in animal models, for efficacy against Mycobacterium leprae challenge in a murine model of leprosy. rBCG30 overexpresses the M. tuberculosis 30-kDa major secretory protein antigen 85B, which is 85% homologous with the M. leprae homolog (r30ML). Mice were sham immunized or immunized intradermally with BCG or rBCG30 and challenged 2.5 months later by injection of viable M. leprae into each hind footpad. After 7 months, vaccine efficacy was assessed by enumerating the M. leprae bacteria per footpad. Both BCG and rBCG30 induced significant protection against M. leprae challenge. In the one experiment in which a comparison between BCG and rBCG30 was feasible, rBCG30 induced significantly greater protection than did BCG. Immunization of mice with purified M. tuberculosis or M. leprae antigen 85B also induced protection against M. leprae challenge but less so than BCG or rBCG30. Notably, boosting rBCG30 with M. tuberculosis antigen 85B significantly enhanced r30ML-specific immune responses, substantially more so than boosting BCG, and significantly augmented protection against M. leprae challenge. Thus, rBCG30, a vaccine that induces improved protection against M. tuberculosis, induces cross-protection against M. leprae that is comparable or potentially superior to that induced by BCG, and boosting rBCG30 with antigen 85B further enhances immune responses and protective efficacy.

  8. Absolute cross section measurements of neutron-induced fission of 242Pu from 1 to 2.5 MeV

    NASA Astrophysics Data System (ADS)

    Matei, C.; Belloni, F.; Heyse, J.; Plompen, A. J. M.; Thomas, D. J.

    2017-02-01

    The absolute neutron-induced fission cross section of 242Pu was measured at five energies between 1 and 2.5 MeV at the low-scatter neutron measurement facility of the National Physical Laboratory, UK. The measurements are part of an effort to reduce uncertainties of nuclear data related to fast spectrum reactors. The neutron-induced fission results are in good agreement with the Evaluated Nuclear Data File/B-VII.1 but disagree with several recent measurements near the resonance-like structure around 1.1 MeV. Within the same experimental campaign, the spontaneous fission half-life of 242Pu was measured and it is in good agreement with previous results.

  9. Extension of activation cross section data of long lived products in deuteron induced nuclear reactions on platinum up to 50 MeV

    NASA Astrophysics Data System (ADS)

    Ditrói, F.; Tárkányi, F.; Takács, S.; Hermanne, A.

    2017-06-01

    In the frame of a systematical study of light ion induced nuclear reactions on platinum, activation cross sections for deuteron induced reactions were investigated. Excitation functions were measured in the 20.8-49.2 MeV energy range for the natPt(d,xn)191,192,193,194,195,196m2,196g,198g,199Au, natPt(d,x)188,189,191,195m,197m,197gPt and natPt(d,x)189,190,192,194m2Ir reactions by using the stacked foil irradiation technique. The experimental results are compared with previous results from the literature and with the theoretical predictions in the TENDL-2014 and TENDL-2015 libraries. The applicability of the produced radio-tracers for wear measurements has been presented.

  10. Lathyrism-induced alterations in collagen cross-links influence the mechanical properties of bone material without affecting the mineral.

    PubMed

    Paschalis, E P; Tatakis, D N; Robins, S; Fratzl, P; Manjubala, I; Zoehrer, R; Gamsjaeger, S; Buchinger, B; Roschger, A; Phipps, R; Boskey, A L; Dall'Ara, E; Varga, P; Zysset, P; Klaushofer, K; Roschger, P

    2011-12-01

    In the present study a rat animal model of lathyrism was employed to decipher whether anatomically confined alterations in collagen cross-links are sufficient to influence the mechanical properties of whole bone. Animal experiments were performed under an ethics committee approved protocol. Sixty-four female (47 day old) rats of equivalent weights were divided into four groups (16 per group): Controls were fed a semi-synthetic diet containing 0.6% calcium and 0.6% phosphorus for 2 or 4 weeks and β-APN treated animals were fed additionally with β-aminopropionitrile (0.1% dry weight). At the end of this period the rats in the four groups were sacrificed, and L2-L6 vertebra were collected. Collagen cross-links were determined by both biochemical and spectroscopic (Fourier transform infrared imaging (FTIRI)) analyses. Mineral content and distribution (BMDD) were determined by quantitative backscattered electron imaging (qBEI), and mineral maturity/crystallinity by FTIRI techniques. Micro-CT was used to describe the architectural properties. Mechanical performance of whole bone as well as of bone matrix material was tested by vertebral compression tests and by nano-indentation, respectively. The data of the present study indicate that β-APN treatment changed whole vertebra properties compared to non-treated rats, including collagen cross-links pattern, trabecular bone volume to tissue ratio and trabecular thickness, which were all decreased (p<0.05). Further, compression tests revealed a significant negative impact of β-APN treatment on maximal force to failure and energy to failure, while stiffness was not influenced. Bone mineral density distribution (BMDD) was not altered either. At the material level, β-APN treated rats exhibited increased Pyd/Divalent cross-link ratios in areas confined to a newly formed bone. Moreover, nano-indentation experiments showed that the E-modulus and hardness were reduced only in newly formed bone areas under the influence of

  11. Prevalence and associated factors of induced abortion among rural married women: a cross-sectional survey in Anhui, China.

    PubMed

    Gao, Guo-Peng; Zhang, Ren-Jie; Zhang, Xiu-Jun; Jia, Xiao-Min; Li, Xiu-De; Li, Xiang; Wang, Cheng-Cheng; Tong, Fei; Sun, Ye-Huan

    2015-03-01

    This study aims to assess the prevalence of and factors associated with induced abortion among married women in rural areas of Anhui Province, China. A multistage probability sampling method was used to identify a representative sample of 53,652 married women aged 18-49 years in rural areas of Anhui Province, China. All women were interviewed in the form of a standardized questionnaire. We found that 32.0% (16,800) of these women had had at least one induced abortion: 21.1% (11,090) of women had had one; 7.6% (3976) of women had had two; and 4.1% (1734) of women had had at least three. The number of induced abortions per 100 pregnancies was found to be 22.0. Multivariate analysis showed that education, the age of a woman at her first marriage, number of total births, number of total pregnancies, and contraceptive methods were significant predictors for induced abortion after controlling for women's current age, employment and family yearly income. The study shows that the prevalence of induced abortion is still very high among married women in rural China, and highly effective methods of contraception (sterilization, intrauterine device) decrease women's recourse to induced abortion. © 2014 The Authors. Journal of Obstetrics and Gynaecology Research © 2014 Japan Society of Obstetrics and Gynecology.

  12. Cross-talk between myeloid-derived suppressor cells (MDSC), macrophages, and dendritic cells enhances tumor-induced immune suppression.

    PubMed

    Ostrand-Rosenberg, Suzanne; Sinha, Pratima; Beury, Daniel W; Clements, Virginia K

    2012-08-01

    The tumor microenvironment is a complex milieu of tumor and host cells. Host cells can include tumor-reactive T cells capable of killing tumor cells. However, more frequently the tumor and host components interact to generate a highly immune suppressive environment that frustrates T cell cytotoxicity and promotes tumor progression through a variety of immune and non-immune mechanisms. Myeloid-derived suppressor cells (MDSC) are a major host component contributing to the immune suppressive environment. In addition to their inherent immune suppressive function, MDSC amplify the immune suppressive activity of macrophages and dendritic cells via cross-talk. This article will review the cell-cell interactions used by MDSC to inhibit anti-tumor immunity and promote progression, and the role of inflammation in promoting cross-talk between MDSC and other cells in the tumor microenvironment.

  13. Activation cross sections of deuteron induced reactions on silver in the 33-50MeV energy range.

    PubMed

    Ditrói, F; Tárkányi, F; Takács, S; Hermanne, A; Ignatyuk, A V

    2017-02-01

    Excitation functions were measured for the (nat)Ag(d,x)(105,104)Cd, (110)(m,108m,106m,105g,104g)Ag and (101)Pd, (105,101m)Rh reactions over the energy range 33-50MeV by using the stacked foil activation technique and subsequent high-resolution gamma-spectrometry. We present the first experimental cross section data above 40MeV for all of these reactions and the first experimental cross section data for (nat)Ag(d,x)(108m,104g)Ag and (105,103)Rh. The experimental data are compared with results of the model calculations performed with the ALICE-D, EMPIRE-D theoretical nuclear reaction model codes and with the TALYS code results as available in the TENDL-2014 and -2015 on-line libraries. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Cross sections for proton-induced reactions on Pd isotopes at energies relevant for the γ process

    NASA Astrophysics Data System (ADS)

    Dillmann, I.; Coquard, L.; Domingo-Pardo, C.; Käppeler, F.; Marganiec, J.; Uberseder, E.; Giesen, U.; Heiske, A.; Feinberg, G.; Hentschel, D.; Hilpp, S.; Leiste, H.; Rauscher, T.; Thielemann, F.-K.

    2011-07-01

    Proton-activation reactions on natural and enriched palladium samples were investigated via the activation technique in the energy range of Ep=2.75-9 MeV, close to the upper end of the respective Gamow window of the γ process. We have determined cross sections for 102Pd(p,γ)103Ag, 104Pd(p,γ)105Ag, and 105Pd(p,n)105Ag, as well as partial cross sections of 104Pd(p,n)104Agg, 105Pd(p,γ)106Agm, 106Pd(p,n)106Agm, and 110Pd(p,n)110Agm with uncertainties between 3% and 15% for constraining theoretical Hauser-Feshbach rates and for direct use in γ-process calculations.

  15. INC Model interpretation of the proton induced residual nuclide production cross sections below 2 GeV

    SciTech Connect

    Divadeenam, M.; Ward, T.E.; Spergel, M.S.; Lakatos, S.; Manche, E.P.

    1991-12-31

    For the purposes of interpreting the abundances of various isotopes in meteorites or on lunar and planetary surfaces exposed to fragmentation by cosmic rays, Webber et al. recently reported the measured total elemental and isotopic cross sections with heavy ions as projectiles on H, He, and C targets with beam energies of 0.33 - 1.7 GeV/nucleon. We employ the INC model to predict the fragmentation of the heavy ions in a hydrogen target with the inverse reaction process: proton bombardment of a heavy-ion nucleus leading to spallation products. Charge-changing and mass-changing cross sections are calculated for proton bombardment of an {sup 56}Fe target with beam energies ranging from 0.33 to 1.88 GeV. Total Z-changing and A-changing cross sections in the energy range 0.6 to 1.88 GeV are in excellent agreement with the corresponding experimental data of Webber et al. and Westfall at al., while the agreement below 0.6 GeV proton energy is not as good. The general trend of the Z-changing cross sections are reproduced by the model calculations at each proton incident energy. The interaction of 200-MeV protons with synthetic Stony Meteorite samples was undertaken to explain radionuclide production in a cosmic-ray environment. The BNL Linac 200-MeV-proton beam was used to irradiate synthetic Stony Meteorites to simulate cosmic-ray exposures corresponding to 6.4 and 16.4 million years. Each irradiated sample was analyzed with the help of a high-resolution gamma-ray spectrometer for long-lived radioisotopes. The intranuclear cascade code HETC was employed to simulate the 200-MeV proton bombardment on the meteorite samples to predict the radionuclides {sup 7}Be, {sup 22}Na, {sup 46}Mn, and {sup 56}Co produced in the experimental investigation.

  16. INC Model interpretation of the proton induced residual nuclide production cross sections below 2 GeV

    SciTech Connect

    Divadeenam, M.; Ward, T.E. ); Spergel, M.S.; Lakatos, S.; Manche, E.P. )

    1991-01-01

    For the purposes of interpreting the abundances of various isotopes in meteorites or on lunar and planetary surfaces exposed to fragmentation by cosmic rays, Webber et al. recently reported the measured total elemental and isotopic cross sections with heavy ions as projectiles on H, He, and C targets with beam energies of 0.33 - 1.7 GeV/nucleon. We employ the INC model to predict the fragmentation of the heavy ions in a hydrogen target with the inverse reaction process: proton bombardment of a heavy-ion nucleus leading to spallation products. Charge-changing and mass-changing cross sections are calculated for proton bombardment of an {sup 56}Fe target with beam energies ranging from 0.33 to 1.88 GeV. Total Z-changing and A-changing cross sections in the energy range 0.6 to 1.88 GeV are in excellent agreement with the corresponding experimental data of Webber et al. and Westfall at al., while the agreement below 0.6 GeV proton energy is not as good. The general trend of the Z-changing cross sections are reproduced by the model calculations at each proton incident energy. The interaction of 200-MeV protons with synthetic Stony Meteorite samples was undertaken to explain radionuclide production in a cosmic-ray environment. The BNL Linac 200-MeV-proton beam was used to irradiate synthetic Stony Meteorites to simulate cosmic-ray exposures corresponding to 6.4 and 16.4 million years. Each irradiated sample was analyzed with the help of a high-resolution gamma-ray spectrometer for long-lived radioisotopes. The intranuclear cascade code HETC was employed to simulate the 200-MeV proton bombardment on the meteorite samples to predict the radionuclides {sup 7}Be, {sup 22}Na, {sup 46}Mn, and {sup 56}Co produced in the experimental investigation.

  17. Reliability of proton-nuclear interaction cross section data to predict proton-induced PET images in proton therapy

    PubMed Central

    España, S; Zhu, X; Daartz, J; El Fakhri, G; Bortfeld, T

    2011-01-01

    In-vivo PET range verification relies on the comparison of measured and simulated activity distributions. The accuracy of the simulated distribution depends on the accuracy of the Monte Carlo code, which is in turn dependent on the accuracy of the available cross sections data for β+ isotope production. We have explored different cross section data available in the literature for the main reaction channels (16O(p,pn)15O, 12C(p,pn)11C and 16O(p,3p3n)11C) contributing to the production of β+ isotopes by proton beams in patients. Available experimental and theoretical values were implemented in the simulation and compared with measured PET images obtained with a high-resolution PET scanner. Each reaction channel was studied independently. A phantom with three different materials was built, two of them with high carbon or oxygen concentration and a third one with average soft tissue composition. Monoenergetic and SOBP field irradiations of the phantom were accomplished and measured PET images were compared with simulation results. Different cross section values for the tissue-equivalent material lead to range differences below 1 mm when a 5 min scan time was employed and close to 5 mm differences for a 30 min scan time with 15 min delay between irradiation and scan (a typical off-line protocol). The results presented here emphasize the need of more accurate measurement of the cross section values of the reaction channels contributing to the production of PET isotopes by proton beams before this in-vivo range verification method can achieve mm accuracy. PMID:21464534

  18. An influenza viral vector Brucella abortus vaccine induces good cross-protection against Brucella melitensis infection in pregnant heifers.

    PubMed

    Tabynov, Kaissar; Ryskeldinova, Sholpan; Sansyzbay, Abylai

    2015-07-17

    Brucella melitensis can be transmitted and cause disease in cattle herds as a result of inadequate management of mixed livestock farms. Ideally, vaccines against Brucella abortus for cattle should also provide cross-protection against B. melitensis. Previously we created a novel influenza viral vector B. abortus (Flu-BA) vaccine expressing the Brucella ribosomal proteins L7/L12 or Omp16. This study demonstrated Flu-BA vaccine with adjuvant Montanide Gel01 provided 100% protection against abortion in vaccinated pregnant heifers and good cross-protection of the heifers and their calves or fetuses (90-100%) after challenge with B. melitensis 16M; the level of protection provided by Flu-BA was comparable to the commercial vaccine B. abortus S19. In terms of the index of infection and colonization of Brucella in tissues, both vaccines demonstrated significant (P=0.02 to P<0.0001) protection against B. melitensis 16M infection compared to the negative control group (PBS+Montanide Gel01). Thus, we conclude the Flu-BA vaccine provides cross-protection against B. melitensis infection in pregnant heifers.

  19. TLR Signals Induce Phagosomal MHC-I Delivery from the Endosomal Recycling Compartment to Allow Cross-Presentation

    PubMed Central

    Nair-Gupta, Priyanka; Baccarini, Alessia; Tung, Navpreet; Seyffer, Fabian; Florey, Oliver; Huang, Yunjie; Huang, Meenakshi; Overholtzer, Michael; Roche, Paul A.; Tampé, Robert; Brown, Brian D.; Amsen, Derk; Whiteheart, Sidney W.; Blander, J. Magarian

    2014-01-01

    SUMMARY Adaptation of the endoplasmic reticulum (ER) pathway for MHC class I (MHC-I) presentation in dendritic cells enables cross-presentation of peptides derived from phagocytosed microbes, infected cells, or tumor cells to CD8 T cells. How these peptides intersect with MHC-I molecules remains poorly understood. Here, we show that MHC-I selectively accumulate within phagosomes carrying microbial components, which engage Toll-like receptor (TLR) signaling. Although cross-presentation requires Sec22b-mediated phagosomal recruitment of the peptide loading complex from the ER-Golgi intermediate compartment (ERGIC), this step is independent of TLR signaling and does not deliver MHC-I. Instead, MHC-I are recruited from an endosomal recycling compartment (ERC), which is marked by Rab11a, VAMP3/cellubrevin, and VAMP8/endobrevin and holds large reserves of MHC-I. While Rab11a activity stocks ERC stores with MHC-I, MyD88-dependent TLR signals drive IκB-kinase (IKK)2-mediated phosphorylation of phagosome-associated SNAP23. Phospho-SNAP23 stabilizes SNARE complexes orchestrating ERC-phagosome fusion, enrichment of phagosomes with ERC-derived MHC-I, and subsequent cross-presentation during infection. PMID:25083866

  20. Heteroimmunization to the capsular polysaccharide of Haemophilus influenzae type b induced by enteric cross-reacting bacteria.

    PubMed

    Handzel, Z T; Argaman, M; Parke, J C; Schneerson, R; Robbins, J B

    1975-05-01

    Cross-reacting Escherichia coli strains Easter and 89 and Bacillus pumilis fed to newborn rabbits and E. coli fed to adult rhesus monkeys did not exert untoward reactions. The E. coli regularly colonized the newborns' intestinal tract from 1 to 7 weeks. High doses of E. coli were necessary to colonize adult primates. Colonization occurred in fewer newborn rabbits and lasted only 1 to 3 weeks with B. pumilis. Colonized newborn rabbits and adult rhesus had an active Haemophilus influenzae type b (HITB) immune response. In the rabbit, colonization resulted in accelerated induction of immunoglobulin (Ig) M-. IgA-, and IgG-producing cells in the spleen, mesenteric lymph nodes, and Peyer's patches after HITB challenge. E. coli-fed and control newborn primates were naturally colonized with nasopharyngeal and enteric cross-reacting bacteria and both groups rapidly developed HITB antibodies in the absence of the homologous organisms. Human newborn stool cultures, taken at the time of discharge from the nursery, showed a 0.9% carriage rate for cross-reacting E. coli. These "carrier" infants acquired HITB antibodies more rapidly than their age-matched "noncarrier" controls.

  1. Measurement of activation cross-sections for high-energy neutron-induced reactions of Bi and Pb

    NASA Astrophysics Data System (ADS)

    Zaman, Muhammad; Kim, Guinyun; Kim, Kwangsoo; Naik, Haladhara; Shahid, Muhammad; Lee, Manwoo

    2015-08-01

    The cross-sections for 209Bi(n, 4n)206Bi, 209Bi(n, 5n)205Bi, natPb(n, xn)204mPb, natPb(n, xn)203Pb, natPb(n, xn)202mPb,natPb(n, xn)201Pb, natPb(n, xn)200Pb, natPb(n, αxn)203Hg and natPb(n, p xn)202Tl reactions were determined at the Korean Institute of Radiological and Medical Sciences (KIRAMS), Korea in the neutron energy range of 15.2 to 37.2 MeV. The above cross-sections were obtained by using the activation and off-line γ-ray spectrometric technique. The quasi-monoenergetic neutron used for the above reactions are based on the 9Be(p, n) reaction. Simulations of the spectral flux from the Be target were done using the MCNPX program. The cross-sections were estimated with the TALYS 1.6 code using the default parameter. The data from the present work and literature were compared with the data from the EAF-2010 and the TENDL-2013 libraries, and calculated values of TALYS 1.6 code. It shows that appropriate level density model, the γ-ray strength function, and the spin cut-off parameter are needed to obtain a good agreement between experimental data and theoretical values from TALYS 1.6 code.

  2. Proton induced gamma-ray production cross sections and thick-target yields for boron, nitrogen and silicon

    NASA Astrophysics Data System (ADS)

    Marchand, Benoît; Mizohata, Kenichiro; Räisänen, Jyrki

    2016-07-01

    The excitation functions for the reactions 14N(p,p‧γ)14N, 28Si(p,p‧γ)28Si and 29Si(p,p‧γ)29Si were measured at an angle of 55° by bombarding a thin Si3N4 target with protons in the energy range of 3.6-6.9 MeV. The deduced γ-ray production cross section data is compared with available literature data relevant for ion beam analytical work. Thick-target γ-ray yields for boron, nitrogen and silicon were measured at 4.0, 4.5, 5.0, 5.5, 6.0 and 6.5 MeV proton energies utilizing thick BN and Si3N4 targets. The measured yield values are put together with available yield data found in the literature. The experimental yield data has been used to cross-check the γ-ray production cross section values by comparing them with calculated thick-target yields deduced from the present and literature experimental excitation curves. All values were found to be in reasonable agreement taking into account the experimental uncertainties.

  3. Cross-linking of CD32 induces maturation of human monocyte-derived dendritic cells via NF-kappa B signaling pathway.

    PubMed

    Bánki, Zoltán; Kacani, Laco; Müllauer, Brigitte; Wilflingseder, Doris; Obermoser, Gerlinde; Niederegger, Harald; Schennach, Harald; Sprinzl, Georg M; Sepp, Norbert; Erdei, Anna; Dierich, Manfred P; Stoiber, Heribert

    2003-04-15

    Dendritic cells (DC) represent a unique set of APCs that initiate immune responses through priming of naive T cells. Maturation of DC is a crucial step during Ag presentation and can be induced by triggering a broad spectrum of DC surface receptors. Although human DC express several receptors for the Fc portion of IgG which were described to play an important role in Ag internalization, little is known about the effects of IgG or immune complexes on DC maturation. In this study, we show that cross-linking of FcgammaR-type II (CD32) with immobilized IgG (imIgG) can induce maturation of human monocyte-derived DC via the NF-kappaB signaling pathway. IgG-mediated maturation was accompanied by a moderate increase of IL-10 secretion, whereas no IL-12 production was observed. Involvement of CD32 was further supported by experiments with the anti-CD32 mAb, which blocked IgG-triggered DC maturation and cytokine secretion significantly. Furthermore, DC cultivated in the presence of imIgG induced allogeneic T cell proliferation. Because this imIgG-induced maturation was considerably impaired in monocyte-derived DC from systemic lupus erythematosus patients, we suggest that DC, which matured in the presence of immune complexes, may contribute to prevention of pathological immune responses.

  4. Cross Talk Between Brain Innate Immunity and Serotonin Signaling Underlies Depressive-Like Behavior Induced by Alzheimer's Amyloid-β Oligomers in Mice.

    PubMed

    Ledo, Jose Henrique; Azevedo, Estefania P; Beckman, Danielle; Ribeiro, Felipe C; Santos, Luis E; Razolli, Daniela S; Kincheski, Grasielle C; Melo, Helen M; Bellio, Maria; Teixeira, Antonio L; Velloso, Licio A; Foguel, Debora; De Felice, Fernanda G; Ferreira, Sergio T

    2016-11-30

    Considerable clinical and epidemiological evidence links Alzheimer's disease (AD) and depression. However, the molecular mechanisms underlying this connection are largely unknown. We reported recently that soluble Aβ oligomers (AβOs), toxins that accumulate in AD brains and are thought to instigate synapse damage and memory loss, induce depressive-like behavior in mice. Here, we report that the mechanism underlying this action involves AβO-induced microglial activation, aberrant TNF-α signaling, and decreased brain serotonin levels. Inactivation or ablation of microglia blocked the increase in brain TNF-α and abolished depressive-like behavior induced by AβOs. Significantly, we identified serotonin as a negative regulator of microglial activation. Finally, AβOs failed to induce depressive-like behavior in Toll-like receptor 4-deficient mice and in mice harboring a nonfunctional TLR4 variant in myeloid cells. Results establish that AβOs trigger depressive-like behavior via a double impact on brain serotonin levels and microglial activation, unveiling a cross talk between brain innate immunity and serotonergic signaling as a key player in mood alterations in AD.

  5. Contraceptive practices and induced abortions status among internal migrant women in Guangzhou, China: a cross-sectional study.

    PubMed

    Zeng, Jiazhi; Zou, Guanyang; Song, Xiaoqin; Ling, Li

    2015-06-17

    China is facing the unprecedented challenges of internal migration. Migrants tend to have poorer utilization of health and family planning services as compared to the local residents. Migrant women are at greater risk of induced abortions due to their poor contraceptive knowledge and attitude. This study aims to understand the contraceptive practices and history of induced abortions, explore the potential factors influencing induced abortions, and evaluate the utilization of family planning services among migrant women in Guangzhou, China. An anonymous, self-administered questionnaire survey was conducted with 1003 migrant women aged 18-49 in Guangzhou, China in 2013. A multi-stage sampling method was employed. Binary logistic regression model was used for analyzing risk factors of induced abortions. Among the 1003 participants, 810 (80.8 %) reported having sex in the past 6 months, including 715 (88.3 %) married and 95 (11.7 %) unmarried. The most reported contraceptive method was male condom (44.9 %), while 8.1 % never used any contraceptive methods. Only 10.4 % reported having attained free condoms from family planning service stations (FPSSs) and 39.3 % reported having acquired contraceptive knowledge from family planning workers. Of all the participants, 417 (41.6 %) had a history of induced abortion. Of married and unmarried women, 389 (49.1 %) and 28 (14.0 %) had induced abortion respectively. Of these, 152 (36.5 %) had repeated abortions. The most reported reason for having induced abortion was failure of contraception (31.9 %), followed by nonuse of any contraceptives (21.1 %). Migrants who had induced abortion tended to be older, have household registration outside Guangdong province, receive no annual health checkup, have lower education, have urban household registration, have lived longer in Guangzhou and have children (P < 0.05). The prevalence rate of induced abortion, especially repeated abortions among migrant women was high in Guangzhou, China

  6. A novel setup for the determination of absolute cross sections for low-energy electron induced strand breaks in oligonucleotides - The effect of the radiosensitizer 5-fluorouracil*

    NASA Astrophysics Data System (ADS)

    Rackwitz, Jenny; Ranković, Miloš Lj.; Milosavljević, Aleksandar R.; Bald, Ilko

    2017-02-01

    Low-energy electrons (LEEs) play an important role in DNA radiation damage. Here we present a method to quantify LEE induced strand breakage in well-defined oligonucleotide single strands in terms of absolute cross sections. An LEE irradiation setup covering electron energies <500 eV is constructed and optimized to irradiate DNA origami triangles carrying well-defined oligonucleotide target strands. Measurements are presented for 10.0 and 5.5 eV for different oligonucleotide targets. The determination of absolute strand break cross sections is performed by atomic force microscopy analysis. An accurate fluence determination ensures small margins of error of the determined absolute single strand break cross sections σ SSB . In this way, the influence of sequence modification with the radiosensitive 5-Fluorouracil (5FU) is studied using an absolute and relative data analysis. We demonstrate an increase in the strand break yields of 5FU containing oligonucleotides by a factor of 1.5 to 1.6 compared with non-modified oligonucleotide sequences when irradiated with 10 eV electrons.

  7. Habituation of enterotoxigenic Staphylococcus aureus to Origanum vulgare L. essential oil does not induce direct-tolerance and cross-tolerance to salts and organic acids.

    PubMed

    Tavares, Adassa Gama; Monte, Daniel Farias Marinho do; Albuquerque, Allan Dos Reis; Sampaio, Fábio Correia; Magnani, Marciane; Siqueira Júnior, José Pinto de; Souza, Evandro Leite de

    2015-01-01

    Enterotoxigenic Staphylococcus aureus strains that were isolated from foods were investigated for their ability to develop direct-tolerance and cross-tolerance to sodium chloride (NaCl), potassium chloride (KCl), lactic acid (LA) and acetic acid (AA) after habituation in sublethal amounts (1/2 of the minimum inhibitory concentration - 1/2 MIC and 1/4 of the minimum inhibitory concentration - 1/4 MIC) of Origanum vulgare L. essential oil (OVEO). The habituation of S. aureus to 1/2 MIC and 1/4 MIC of OVEO did not induce direct-tolerance or cross-tolerance in the tested strains, as assessed by modulation of MIC values. Otherwise, exposing the strains to OVEO at sublethal concentrations maintained or increased the sensitivity of the cells to the tested stressing agents because the MIC values of OVEO, NaCl, KCl, LA and AA against the cells that were previously habituated to OVEO remained the same or decreased when compared with non-habituated cells. These data indicate that OVEO does not have an inductive effect on the acquisition of direct-tolerance or cross-tolerance in the tested enterotoxigenic strains of S. aureus to antimicrobial agents that are typically used in food preservation.

  8. Measurement of numu induced charged current inclusive cross section on water using the near detector of the T2K experiment

    NASA Astrophysics Data System (ADS)

    Das, Rajarshi

    The Tokai to Kamioka (T2K) Experiment is a long-baseline neutrino oscillation experiment located in Japan with the primary goal to measure precisely multiple neutrino flavor oscillation parameters. An off-axis muon neutrino beam peaking at 600 MeV is generated at the JPARC facility and directed towards the 50 kiloton Super-Kamiokande (SK) water Cherenkov detector located 295 km away. Measurements from a Near Detector that is 280m downstream of the neutrino beam target are used to constrain uncertainties in the beam flux prediction and neutrino interaction rates. We present a selection of inclusive charged current neutrino interactions on water. We used several sub-detectors in the ND280 complex, including a Pi-Zero detector (P0D) that has alternating planes of plastic scintillator and water bag layers, a time projection chamber (TPC) and fine-grained detector (FGD) to detect and reconstruct muons from neutrino charged current events. We use a statistical subtraction method with the water-in and water-out inclusive selection to extract a flux-averaged, ν_μ induced, charged current inclusive cross section. We also outline the evaluation of systematic uncertainties. We find an absolute cross section of ⟨σ⟩=(6.37 ± 0.157(stat.) (-1.060/+0.910(sys.)) x 10-39 (cm. 2/H2O nucleon). This is the first ν_μ charged current inclusive cross section measurement on water.

  9. Monitoring of cornea elastic properties changes during UV-A/riboflavin-induced corneal collagen cross-linking using supersonic shear wave imaging: a pilot study.

    PubMed

    Nguyen, Thu-Mai; Aubry, Jean-François; Touboul, David; Fink, Mathias; Gennisson, Jean-Luc; Bercoff, Jeremy; Tanter, Mickael

    2012-08-31

    Keratoconus disease or post-LASIK corneal ectasia are increasingly treated using UV-A/riboflavin-induced corneal collagen cross-linking (CXL). However, this treatment suffers from a lack of techniques to provide an assessment in real-time of the CXL effects. Here, we investigated the potential interest of corneal elasticity as a biomarker of the efficacy of this treatment. For this purpose, supersonic shear wave imaging (SSI) was performed both ex vivo and in vivo on porcine eyes before and after CXL. Based on ultrasonic scanners providing ultrafast frame rates (~30 kHz), the SSI technique generates and tracks the propagation of shear waves in tissues. It prov