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Sample records for americanus induces neutralizing

  1. Inducing Risk Neutral Preferences with Binary Lotteries

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Martínez-Correa, Jimmy; Swarthout, J. Todd

    2013-01-01

    We evaluate the binary lottery procedure for inducing risk neutral behavior. We strip the experimental implementation down to bare bones, taking care to avoid any potentially confounding assumptions about behavior having to be made. In particular, our evaluation does not rely on the assumed...... validity of any strategic equilibrium behavior, or even the customary independence axiom. We show that subjects sampled from our population are generally risk averse when lotteries are defined over monetary outcomes, and that the binary lottery procedure does indeed induce a statistically significant shift...... toward risk neutrality. This striking result generalizes to the case in which subjects make several lottery choices and one is selected for payment....

  2. Neutral current induced π0 production and neutrino magnetic moment

    International Nuclear Information System (INIS)

    We have studied the total cross section, Q2, momentum and angular distributions for pions in the ν(ν) induced π0 production from nucleons. The calculations have been done for the weak production induced by the neutral current in the standard model and the electromagnetic production induced by neutrino magnetic moment. It has been found that with the present experimental limits on the muon neutrino magnetic moment μνμ, the electromagnetic contribution to the cross section for the π0 production is small. The neutrino induced neutral current production of π0, while giving an alternative method to study the magnetic moment of neutrino μνμ, does not provide any improvement over the present experimental limit on μνμ from the observation of this process in future experiments at T2K and NOνA.

  3. Disorder-induced neutral solitons in degenerate ground state polymers

    NARCIS (Netherlands)

    Figge, M. T.; Mostovoy, M. V.; Knöster, J.

    1999-01-01

    Submitted to: Synth. Met. Abstract: In this letter, we study the effects of weak off-diagonal disorder on conjugated polymers with a doubly degenerate ground-state. We find that disorder induces a finite density of neutral solitons in the lattice dimerization of a polymer chain. Interchain interacti

  4. CHARACTERIZATION OF MICROSATELLITE LOCI IN SCHOENOPLECTUS AMERICANUS (CYPERACEAE)

    Science.gov (United States)

    Schoenoplectus americanus is a model organism for studying ecological and ecosystem responses of salt marsh plant communities to global climate change. Here we characterize 16 microsatellite loci in S. americanus to facilitate studies on the genetic basis of phenotypic responses...

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

    International Nuclear Information System (INIS)

    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 V3B-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.

  6. Dual neutral particle induced transmutation in CINDER2008

    International Nuclear Information System (INIS)

    Although nuclear transmutation methods for fission have existed for decades, the focus has been on neutron-induced reactions. Recent novel concepts have sought to use both neutrons and photons for purposes such as active interrogation of cargo to detect the smuggling of highly enriched uranium, a concept that would require modeling the transmutation caused by both incident particles. As photonuclear transmutation has yet to be modeled alongside neutron-induced transmutation in a production code, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron applications to dual neutral particle applications, allowing both neutron- and photon-induced reactions for this modeling with a focus on fission. Following standard reaction modeling, the induced fission reaction is understood as a two-part reaction, with an entrance channel to the excited compound nucleus, and an exit channel from the excited compound nucleus to the fission fragmentation. Because photofission yield data—the exit channel from the compound nucleus—are sparse, neutron fission yield data are used in this work. With a different compound nucleus and excitation, the translation to the excited compound state is modified, as appropriate. A verification and validation of these methods and data has been performed. This has shown that the translation of neutron-induced fission product yield sets, and their use in photonuclear applications, is appropriate, and that the code has been extended correctly. - Highlights: • The CINDER2008 transmutation code was modified to include photon-induced transmutation tracking. • A photonuclear interaction library was created to allow CINDER2008 to track photonuclear interactions. • Photofission product yield data sets were created using fission physics similarities with neutron-induced fission

  7. Dual neutral particle induced transmutation in CINDER2008

    Energy Technology Data Exchange (ETDEWEB)

    Martin, W.J., E-mail: wjmarti@sandia.gov [Sandia National Laboratories, Albuquerque, NM 87185 (United States); University of New Mexico, Albuquerque, NM 87131 (United States); Oliveira, C.R.E. de; Hecht, A.A. [University of New Mexico, Albuquerque, NM 87131 (United States)

    2014-12-11

    Although nuclear transmutation methods for fission have existed for decades, the focus has been on neutron-induced reactions. Recent novel concepts have sought to use both neutrons and photons for purposes such as active interrogation of cargo to detect the smuggling of highly enriched uranium, a concept that would require modeling the transmutation caused by both incident particles. As photonuclear transmutation has yet to be modeled alongside neutron-induced transmutation in a production code, new methods need to be developed. The CINDER2008 nuclear transmutation code from Los Alamos National Laboratory is extended from neutron applications to dual neutral particle applications, allowing both neutron- and photon-induced reactions for this modeling with a focus on fission. Following standard reaction modeling, the induced fission reaction is understood as a two-part reaction, with an entrance channel to the excited compound nucleus, and an exit channel from the excited compound nucleus to the fission fragmentation. Because photofission yield data—the exit channel from the compound nucleus—are sparse, neutron fission yield data are used in this work. With a different compound nucleus and excitation, the translation to the excited compound state is modified, as appropriate. A verification and validation of these methods and data has been performed. This has shown that the translation of neutron-induced fission product yield sets, and their use in photonuclear applications, is appropriate, and that the code has been extended correctly. - Highlights: • The CINDER2008 transmutation code was modified to include photon-induced transmutation tracking. • A photonuclear interaction library was created to allow CINDER2008 to track photonuclear interactions. • Photofission product yield data sets were created using fission physics similarities with neutron-induced fission.

  8. Genome of the human hookworm Necator americanus.

    Science.gov (United States)

    Tang, Yat T; Gao, Xin; Rosa, Bruce A; Abubucker, Sahar; Hallsworth-Pepin, Kymberlie; Martin, John; Tyagi, Rahul; Heizer, Esley; Zhang, Xu; Bhonagiri-Palsikar, Veena; Minx, Patrick; Warren, Wesley C; Wang, Qi; Zhan, Bin; Hotez, Peter J; Sternberg, Paul W; Dougall, Annette; Gaze, Soraya Torres; Mulvenna, Jason; Sotillo, Javier; Ranganathan, Shoba; Rabelo, Elida M; Wilson, Richard K; Felgner, Philip L; Bethony, Jeffrey; Hawdon, John M; Gasser, Robin B; Loukas, Alex; Mitreva, Makedonka

    2014-03-01

    The hookworm Necator americanus is the predominant soil-transmitted human parasite. Adult worms feed on blood in the small intestine, causing iron-deficiency anemia, malnutrition, growth and development stunting in children, and severe morbidity and mortality during pregnancy in women. We report sequencing and assembly of the N. americanus genome (244 Mb, 19,151 genes). Characterization of this first hookworm genome sequence identified genes orchestrating the hookworm's invasion of the human host, genes involved in blood feeding and development, and genes encoding proteins that represent new potential drug targets against hookworms. N. americanus has undergone a considerable and unique expansion of immunomodulator proteins, some of which we highlight as potential treatments against inflammatory diseases. We also used a protein microarray to demonstrate a postgenomic application of the hookworm genome sequence. This genome provides an invaluable resource to boost ongoing efforts toward fundamental and applied postgenomic research, including the development of new methods to control hookworm and human immunological diseases. PMID:24441737

  9. Evaluation of antivenoms in the neutralization of hyperalgesia and edema induced by Bothrops jararaca and Bothrops asper snake venoms

    Directory of Open Access Journals (Sweden)

    Picolo G.

    2002-01-01

    Full Text Available Neutralization of hyperalgesia induced by Bothrops jararaca and B. asper venoms was studied in rats using bothropic antivenom produced at Instituto Butantan (AVIB, 1 ml neutralizes 5 mg B. jararaca venom and polyvalent antivenom produced at Instituto Clodomiro Picado (AVCP, 1 ml neutralizes 2.5 mg B. aspar venom. The intraplantar injection of B. jararaca and B. asper venoms caused hyperalgesia, which peaked 1 and 2 h after injection, respectively. Both venoms also induced edema with a similar time course. When neutralization assays involving the independent injection of venom and antivenom were performed, the hyperalgesia induced by B. jararaca venom was neutralized only when bothropic antivenom was administered iv 15 min before venom injection, whereas edema was neutralized when antivenom was injected 15 min or immediately before venom injection. On the other hand, polyvalent antivenom did not interfere with hyperalgesia or edema induced by B. asper venom, even when administered prior to envenomation. The lack of neutralization of hyperalgesia and edema induced by B. asper venom is not attributable to the absence of neutralizing antibodies in the antivenom, since neutralization was achieved in assays involving preincubation of venom and antivenom. Cross-neutralization of AVCP or AVIB against B. jararaca and B. asper venoms, respectively, was also evaluated. Only bothropic antivenom partially neutralized hyperalgesia induced by B. asper venom in preincubation experiments. The present data suggest that hyperalgesia and edema induced by Bothrops venoms are poorly neutralized by commercial antivenoms even when antibodies are administered immediately after envenomation.

  10. Decoherence induced CPT violation and entangled neutral mesons

    International Nuclear Information System (INIS)

    We discuss two classes of semimicroscopic theoretical models of stochastic spacetime foam in quantum gravity and the associated effects on entangled states of neutral mesons, signalling an intrinsic breakdown of CPT invariance. One class of models deals with a specific model of foam, initially constructed in the context of noncritical (Liouville) string theory, but viewed here in the more general context of effective quantum-gravity models. The relevant Hamiltonian perturbation, describing the interaction of the meson with the foam medium, consists of off-diagonal stochastic metric fluctuations, connecting distinct mass eigenstates (or the appropriate generalization thereof in the case of K-mesons), and it is proportional to the relevant momentum transfer (along the direction of motion of the meson pair). There are two kinds of CPT-violating effects in this case, which can be experimentally disentangled: one (termed 'ω-effect') is associated with the failure of the indistinguishability between the neutral meson and its antiparticle, and affects certain symmetry properties of the initial state of the two-meson system; the second effect is generated by the time evolution of the system in the medium of the spacetime foam, and can result in time-dependent contributions of the ω-effect type in the time profile of the two-meson state. Estimates of both effects are given, which show that, at least in certain models, such effects are not far from the sensitivity of experimental facilities available currently or in the near future. The other class of quantum-gravity models involves a medium of gravitational fluctuations which behaves like a 'thermal bath'. In this model both of the above-mentioned intrinsic CPT violation effects are not valid

  11. Large-Scale Examination of Factors Influencing Phosphopeptide Neutral Loss during Collision Induced Dissociation

    Science.gov (United States)

    Brown, Robert; Stuart, Scott S.; Houel, Stephane; Ahn, Natalie G.; Old, William M.

    2015-07-01

    Collision-induced dissociation (CID) remains the predominant mass spectrometry-based method for identifying phosphorylation sites in complex mixtures. Unfortunately, the gas-phase reactivity of phosphoester bonds results in MS/MS spectra dominated by phosphoric acid (H3PO4) neutral loss events, suppressing informative peptide backbone cleavages. To understand the major drivers of H3PO4 neutral loss, we performed robust nonparametric statistical analysis of local and distal sequence effects on the magnitude and variability of neutral loss, using a collection of over 35,000 unique phosphopeptide MS/MS spectra. In contrast to peptide amide dissociation pathways, which are strongly influenced by adjacent amino acid side chains, we find that neutral loss of H3PO4 is affected by both proximal and distal sites, most notably basic residues and the peptide N-terminal primary amine. Previous studies have suggested that protonated basic residues catalyze neutral loss through direct interactions with the phosphate. In contrast, we find that nearby basic groups decrease neutral loss regardless of mobility class, an effect only seen by stratifying spectra by charge-mobility. The most inhibitory bases are those immediately N-terminal to the phosphate, presumably because of steric hindrances in catalyzing neutral loss. Further evidence of steric effects is shown by the presence of proline, which can dramatically reduce the presence of neutral loss when between the phosphate and a possible charge donor. In mobile proton spectra, the N-terminus is the strongest predictor of high neutral loss, with proximity to the N-terminus essential for peptides to exhibit the highest levels of neutral loss.

  12. Neutral-pion reactions induced by chiral anomaly in strong magnetic fields

    CERN Document Server

    Hattori, Koichi; Ozaki, Sho

    2013-01-01

    We investigate decay and production of neutral pions in strong magnetic fields. In the presence of strong magnetic fields, transition between a neutral pion and a virtual photon becomes possible through the triangle diagram relevant for the chiral anomaly. We find that the decay mode of a neutral pion into two photons cannot persist in the dominant mode in strong magnetic fields, and that decay into a dilepton instead dominates over the other modes. We also investigate the effects of magnetic fields on prompt virtual photons created in ultrarelativistic heavy-ion collisions. There is no anisotropy in the spectrum at the stage of creation of prompt virtual photons, but after traversing the strong magnetic field that is induced perpendicularly to the reaction plane, virtual photons turn into neutral pions, leading to an anisotropic spectrum of dileptons as a feasible signature in the measurement.

  13. Non-Neutral Marginal Research Costs and Induced Innovation

    OpenAIRE

    Lee, Daegoon; Cowan, Benjamin W.; Shumway, C. Richard

    2015-01-01

    We test Hicks’ induced innovation hypothesis (IIH) in U.S. agriculture using a state-level panel dataset of input prices and quantities for the period 1960-2004. A two-stage cost minimization model where decisions of research investment allocation predates those of input allocations is set forth. Parametric relationships between expected relative price change and input quantity allocation that represent technical changes are obtained distinctively from those between current relative price cha...

  14. Structural Constraints of Vaccine-Induced Tier-2 Autologous HIV Neutralizing Antibodies Targeting the Receptor-Binding Site

    Directory of Open Access Journals (Sweden)

    Todd Bradley

    2016-01-01

    Full Text Available Antibodies that neutralize autologous transmitted/founder (TF HIV occur in most HIV-infected individuals and can evolve to neutralization breadth. Autologous neutralizing antibodies (nAbs against neutralization-resistant (Tier-2 viruses are rarely induced by vaccination. Whereas broadly neutralizing antibody (bnAb-HIV-Envelope structures have been defined, the structures of autologous nAbs have not. Here, we show that immunization with TF mutant Envs gp140 oligomers induced high-titer, V5-dependent plasma neutralization for a Tier-2 autologous TF evolved mutant virus. Structural analysis of autologous nAb DH427 revealed binding to V5, demonstrating the source of narrow nAb specificity and explaining the failure to acquire breadth. Thus, oligomeric TF Envs can elicit autologous nAbs to Tier-2 HIVs, but induction of bnAbs will require targeting of precursors of B cell lineages that can mature to heterologous neutralization.

  15. Visual optics in toads (Bufo americanus).

    Science.gov (United States)

    Mathis, U; Schaeffel, F; Howland, H C

    1988-06-01

    Aspects of visual optics were investigated in the American toad (Bufo americanus). The development of the refractive state of the eye during metamorphosis was followed with IR photoretinoscopy. Frozen sections documented the changes in optical parameters before and after metamorphosis. There is a difference in light sensitivity between juvenile and adult toads. Binocular accommodation in adult toads was observed. 1. IR photoretinoscopic measurements showed that the refractive state of the eye changed very rapidly during metamorphosis, about 10 D/h while the animal entered the terrestrial habitat. 2. Frozen sections showed that the almost spherical lens in a tadpole eye had flattened in a just metamorphosed toad's eye while at the same time the distance of the lens to the retina had decreased. However, the morphological measurements were not sufficiently sensitive to record the relatively small changes in ocular dimensions that were responsible for the rapid changes in refractive state during metamorphosis. 3. Schematic eyes, with homogeneous and non homogeneous lenses, were constructed for tadpoles, juvenile toads, and adult toads. 4. Nonparaxial raytracing studies in schematic eyes suggested that the lenses of animals of the three developmental stages tadpole, juvenile toad, and adult are not homogeneous but have a refractive index gradient. The raytracing studies indicated that the refractive index gradient is different for the different developmental stages, being highest in the tadpole lens. 5. The observations of toads during feeding behavior at different light levels showed an increased light sensitivity in the adult nocturnal toads in contrast to the juvenile animals, which are diurnal. The increased light sensitivity could partly be explained with an increase in aperture and an increase in red rod outer segments. To fully explain the higher light sensitivity in adult toads, changes in neuronal parameters had to be assumed. 6. Retinoscopic measurements of

  16. Fisheries-induced neutral and adaptive evolution in exploited fish populations and consequences for their adaptive potential

    DEFF Research Database (Denmark)

    Marty, Lise; Dieckmann, Ulf; Ernande, Bruno

    2015-01-01

    Fishing may induce neutral and adaptive evolution affecting life-history traits, and molecular evidence has shown that neutral genetic diversity has declined in some exploited populations. Here, we theoretically study the interplay between neutral and adaptive evolution caused by fishing. An...... individual-based eco-genetic model is devised that includes neutral and functional loci in a realistic ecological setting. In line with theoretical expectations, we find that fishing induces evolution towards slow growth, early maturation at small size and higher reproductive investment. We show, first, that...

  17. Aharonov-Bohm scattering of neutral atoms with induced electric dipole moments

    OpenAIRE

    Audretsch, Juergen; Skarzhinsky, Vladimir

    1998-01-01

    We investigate the scattering of neutral polarizable atoms from an electrically charged wire placed in a homogeneous magnetic field. The atoms carry an induced electric dipole. The reflecting wire is discussed. We calculate the scattering amplitude and cross section the practically more important case that atoms are totally absorbed at the surface of the wire. If the magnetic field is present, there is a dominating Aharonov-Bohm peak in the forward direction followed by decreasing oscillation...

  18. Cure of Chronic Viral Infection and Virus-Induced Type 1 Diabetes by Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Mette Ejrnaes

    2006-01-01

    Full Text Available The use of neutralizing antibodies is one of the most successful methods to interfere with receptor-ligand interactions in vivo. In particular blockade of soluble inflammatory mediators or their corresponding cellular receptors was proven an effective way to regulate inflammation and/or prevent its negative consequences. However, one problem that comes along with an effective neutralization of inflammatory mediators is the general systemic immunomodulatory effect. It is therefore important to design a treatment regimen in a way to strike at the right place and at the right time in order to achieve maximal effects with minimal duration of immunosuppression or hyperactivation. In this review we reflect on two examples of how short time administration of such neutralizing antibodies can block two distinct inflammatory consequences of viral infection. First, we review recent findings that blockade of IL-10/IL-10R interaction can resolve chronic viral infection and second, we reflect on how neutralization of the chemokine CXCL10 can abrogate virus-induced type 1 diabetes.

  19. Massively parallel sequencing and analysis of the Necator americanus transcriptome.

    Directory of Open Access Journals (Sweden)

    Cinzia Cantacessi

    Full Text Available BACKGROUND: The blood-feeding hookworm Necator americanus infects hundreds of millions of people worldwide. In order to elucidate fundamental molecular biological aspects of this hookworm, the transcriptome of the adult stage of Necator americanus was explored using next-generation sequencing and bioinformatic analyses. METHODOLOGY/PRINCIPAL FINDINGS: A total of 19,997 contigs were assembled from the sequence data; 6,771 of these contigs had known orthologues in the free-living nematode Caenorhabditis elegans, and most of them encoded proteins with WD40 repeats (10.6%, proteinase inhibitors (7.8% or calcium-binding EF-hand proteins (6.7%. Bioinformatic analyses inferred that the C. elegans homologues are involved mainly in biological pathways linked to ribosome biogenesis (70%, oxidative phosphorylation (63% and/or proteases (60%; most of these molecules were predicted to be involved in more than one biological pathway. Comparative analyses of the transcriptomes of N. americanus and the canine hookworm, Ancylostoma caninum, revealed qualitative and quantitative differences. For instance, proteinase inhibitors were inferred to be highly represented in the former species, whereas SCP/Tpx-1/Ag5/PR-1/Sc7 proteins ( = SCP/TAPS or Ancylostoma-secreted proteins were predominant in the latter. In N. americanus, essential molecules were predicted using a combination of orthology mapping and functional data available for C. elegans. Further analyses allowed the prioritization of 18 predicted drug targets which did not have homologues in the human host. These candidate targets were inferred to be linked to mitochondrial (e.g., processing proteins or amino acid metabolism (e.g., asparagine t-RNA synthetase. CONCLUSIONS: This study has provided detailed insights into the transcriptome of the adult stage of N. americanus and examines similarities and differences between this species and A. caninum. Future efforts should focus on comparative transcriptomic and

  20. Oligo-lysine Induced Formation of Silica Particles in Neutral Silicate Solution

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Oligo-(lysine)n (n = 1-4) containing different numbers of lysine residues was used to induce the condensation of silicic acid to form silica particles in neutral silicate solution. It was found that the condensation rate and the formation of silica particles are dependent on the number of lysine residues in an oligo-lysine. Oligo-lysine with more lysine residues can link more silicic acid together to form a matrix that promotes the effective aggregation of the condensed silica pieces to form large silica particles.

  1. New tests of weak interaction models in neutral current-induced weak pion production

    International Nuclear Information System (INIS)

    The purpose of this paper is to propose the measurement of asymmetry in neutral current-induced weak pion production, and to show that it will serve as the sensitive test of the models for weak interaction. The notable difference among various models appears in the structure of the neutral current. The general form of the hadronic neutral current is introduced. As typical examples, the standard Weinberg-Salam-GIM model (W-S-GIM), the Fritzsch-Gell-Mann-Minkowski model (F-G-M), and the Barnett model are considered. The differential cross-section for the weak pion production can be derived. The asymmetries A1 and A2 are estimated. The predicted values of A1 and A2 for W-S-GIM, F-G-M and Barnett models at the incident neutrino energy of 1 GeV are tabulated. It should be noted that the F-G-M model predicts the different values of the asymmetries from the W-S-GIM model. The difference is large enough to be distinguishable in future experiment. (Kato, T.)

  2. Description-based reappraisal regulate the emotion induced by erotic and neutral images in a Chinese population

    Directory of Open Access Journals (Sweden)

    Jiaxin ePeng

    2013-01-01

    Full Text Available Previous emotion-regulation research has shown that the late positive potential (LPP is sensitive to the down-regulation of emotion; however, whether LPP is also sensitive to the up-regulation of emotion remains unclear. The present study examined the description-based reappraisal effects on the up-regulation of positive emotions induced by erotic and neutral images in a Chinese population. Self-reported ratings and event-related potential (ERP were recorded when subjects viewed pleasant and neutral images, which were shown after either a neutral or positive description. Self-reported results showed that images following positive descriptions were rated as more pleasant compared to images following neutral descriptions. ERP results revealed that the P2, P3, and slow wave (SW components were larger for erotic pictures than for neutral pictures, while the positive description condition yielded attenuated erotic image-induced P2, P3 and SW and increased SW induced by neutral images. The results demonstrated that description-based reappraisal, as a method of reappraisal, significantly modulates the emotional experience and ERP responses to erotic and neutral images.

  3. Precipitation of Energetic Neutral Atoms and Induced Non-Thermal Escape Fluxes from the Martian Atmosphere

    CERN Document Server

    Lewkow, Nicholas

    2014-01-01

    The precipitation of energetic neutral atoms (ENAs), produced through charge exchange (CX) collisions between solar wind (SW) ions and thermal atmospheric gases, is investigated. Subsequent induced non-thermal escape fluxes have been carried out for the Martian atmosphere. Detailed modeling of the ENA energy input and determination of connections between parameters of precipitating ENAs and resulting escape fluxes, reflection coefficients of fast atoms from the Mars atmosphere, and altitude dependent ENA energy distributions are established using Monte Carlo (MC) simulations of the precipitation process with accurate quantum mechanical (QM) cross sections. Detailed descriptions of secondary hot (SH) atoms and molecules induced by ENAs have been obtained for a better understanding of the mechanisms responsible for atmospheric escape and evolution. The effects of using isotropic hard sphere (HS) cross sections as compared to realistic, anisotropic quantum cross sections are examined for energy-deposition profil...

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

    OpenAIRE

    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

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

    Science.gov (United States)

    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. PMID:27314914

  6. Probiotic sonicates selectively induce mucosal immune cells apoptosis through ceramide generation via neutral sphingomyelinase.

    Directory of Open Access Journals (Sweden)

    Sandra Angulo

    Full Text Available BACKGROUND: Probiotics appear to be beneficial in inflammatory bowel disease, but their mechanism of action is incompletely understood. We investigated whether probiotic-derived sphingomyelinase mediates this beneficial effect. METHODOLOGY/PRINCIPAL FINDINGS: Neutral sphingomyelinase (NSMase activity was measured in sonicates of the probiotic L. brevis (LB and S. thermophilus (ST and the non-probiotic E. coli (EC and E. faecalis (EF. Lamina propria mononuclear cells (LPMC were obtained from patients with Crohn's disease (CD and Ulcerative Colitis (UC, and peripheral blood mononuclear cells (PBMC from healthy volunteers, analysing LPMC and PBMC apoptosis susceptibility, reactive oxygen species (ROS generation and JNK activation. In some experiments, sonicates were preincubated with GSH or GW4869, a specific NSMase inhibitor. NSMase activity of LB and ST was 10-fold that of EC and EF sonicates. LB and ST sonicates induced significantly more apoptosis of CD and UC than control LPMC, whereas EC and EF sonicates failed to induce apoptosis. Pre-stimulation with anti-CD3/CD28 induced a significant and time-dependent increase in LB-induced apoptosis of LPMC and PBMC. Exposure to LB sonicates resulted in JNK activation and ROS production by LPMC. NSMase activity of LB sonicates was completely abrogated by GW4869, causing a dose-dependent reduction of LB-induced apoptosis. LB and ST selectively induced immune cell apoptosis, an effect dependent on the degree of cell activation and mediated by bacterial NSMase. CONCLUSIONS: These results suggest that induction of immune cell apoptosis is a mechanism of action of some probiotics, and that NSMase-mediated ceramide generation contributes to the therapeutic effects of probiotics.

  7. Theory of asymmetry-induced transport in a non-neutral plasma

    International Nuclear Information System (INIS)

    Radial transport produced by static nonaxisymmetric fields is thought to limit the confinement of non-neutral plasmas and experiments with applied asymmetries have verified that such fields do produce transport. A theoretical model of such transport is presented which is appropriate for long, thin plasmas. The theory allows for asymmetries with nonzero frequency and includes the linear collective response to applied wall voltages. For the regime where the effective collision frequency is large, the asymmetry-induced radial particle flux is derived from the drift kinetic/Poisson equations including collisions. For low collision frequencies a heuristic derivation is given. In both regimes the resulting transport is dominated by particles that move in resonance with the asymmetry. Possible applications of the theory to several experiments are discussed. copyright 1999 American Institute of Physics

  8. Disorder-induced heating of ultracold neutral plasmas created from atoms in partially filled optical lattices

    Science.gov (United States)

    Murphy, D.; Sparkes, B. M.

    2016-08-01

    We quantify the disorder-induced heating (DIH) of ultracold neutral plasmas (UCNPs) created from cold atoms in optical lattices with partial filling fractions, using a conservation of energy model involving the spatial correlations of the initial state and the equation of state in thermal equilibrium for a one-component plasma. We show, for experimentally achievable filling fractions, that the ionic Coulomb coupling parameter could be increased to a degree comparable to other proposed DIH-mitigation schemes. Molecular dynamics simulations were performed with compensation for finite-size and periodic boundary effects, which agree with calculations using the model. Reduction of DIH using optical lattices will allow for the study of strongly coupled plasma physics using low-density, low-temperature, laboratory-based plasmas, and lead to improved brightness in UCNP-based cold electron and ion beams, where DIH is otherwise a fundamental limitation to beam focal sizes and diffraction imaging capability.

  9. Weak charged and neutral current induced one pion production off the nucleon

    CERN Document Server

    Alam, M Rafi; Chauhan, S; Singh, S K

    2015-01-01

    We present a study of neutrino/antineutrino induced charged and neutral current single pion production off the nucleon. For this, we have considered $P_{33}(1232)$ resonance, non-resonant background terms, other higher resonances like $P_{11}(1440)$, $S_{11}(1535)$, $D_{13}(1520)$, $S_{11}(1650)$ and $P_{13}(1720)$. For the non-resonant background terms a microscopic approach based on SU(2) non-linear sigma model has been used. The vector form factors for the resonances are obtained by using the relationship between the electromagnetic resonance form factors and helicity amplitudes provided by MAID. Axial coupling $C_5^{A}(0)$ in the case of $P_{33}(1232)$ resonance is obtained by fitting the ANL and BNL $\

  10. Amplitude scaling of asymmetry-induced transport in a non-neutral plasma trap

    International Nuclear Information System (INIS)

    Initial experiments on asymmetry-induced transport in the Occidental non-neutral plasma trap found the radial particle flux at small radii to be proportional to φa2, where φa is the applied asymmetry amplitude. Other researchers, however, using the global expansion rate as a measure of the transport, have observed a φa1 scaling when the rigidity (the ratio of the axial bounce frequency to the azimuthal rotation frequency) is in the range of 1-10. In an effort to resolve this discrepancy, measurements have been extended to different radii and asymmetry frequencies. Although the results to date are generally in agreement with those previously reported (φa2 scaling at low asymmetry amplitudes falling off to a weaker scaling at higher amplitudes), some cases have been observed where the low amplitude scaling is closer to φa1. Both the φa2 and φa1 cases, however, have rigidities less than 10. Instead, the φa1 cases are characterized by an induced flux that is comparable in magnitude but opposite in sign to the background flux. This suggests that the mixing of applied and background asymmetries plays an important role in determining the amplitude scaling of this transport

  11. Preparation of an antibody that recognizes and neutralizes Dictyostelium differentiation-inducing factor-1.

    Science.gov (United States)

    Kubohara, Yuzuru; Kikuchi, Haruhisa; Nakamura, Koji; Matsuo, Yusuke; Oshima, Yoshiteru

    2010-05-28

    In the development of the cellular slime mold Dictyostelium discoideum, the differentiation-inducing factor-1 (DIF-1; 1-(3,5-dichloro-2,6-dihydroxy-4-methoxyphenyl)hexan-1-one) plays an important role in the regulation of cell differentiation and chemotaxis; however, the cellular signaling systems involving DIF-1 remain to be elucidated. To obtain a probe for DIF-1, we synthesized a DIF derivative (DIF-1-NH(2); 6-amino-1-(3,5-dichloro-2,6-dihydroxy-4-methoxyphenyl)hexan-1-one), and prepared an anti-DIF-1 antibody using a DIF-1-NH(2)-conjugated macromolecule as the immunogen. A 100-fold dilution of the antibody bound to DIF-1-NH(2)-conjugated resin, and this binding was inhibited by co-addition of 20 microM DIF-1 or DIF-1-NH(2). In a monolayer culture of HM44 cells, a DIF-deficient D. discoideum strain, 0.5 nM exogenous DIF-1 induced stalk cell formation in approximately 60% of the cells; this induction was dose-dependently inhibited by the antibody (diluted 12.5- or 25-fold). Furthermore, this inhibition by the antibody was recovered by co-addition of 2.5 or10 nM DIF-1. The results indicate that the anti-DIF-1 antibody recognizes DIF-1 and neutralizes its function. PMID:20416278

  12. Precipitation of energetic neutral atoms and induced non-thermal escape fluxes from the Martian atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Lewkow, N. R.; Kharchenko, V. [Department of Physics, University of Connecticut, Storrs, CT 06269 (United States)

    2014-08-01

    The precipitation of energetic neutral atoms, produced through charge exchange collisions between solar wind ions and thermal atmospheric gases, is investigated for the Martian atmosphere. Connections between parameters of precipitating fast ions and resulting escape fluxes, altitude-dependent energy distributions of fast atoms and their coefficients of reflection from the Mars atmosphere, are established using accurate cross sections in Monte Carlo (MC) simulations. Distributions of secondary hot (SH) atoms and molecules, induced by precipitating particles, have been obtained and applied for computations of the non-thermal escape fluxes. A new collisional database on accurate energy-angular-dependent cross sections, required for description of the energy-momentum transfer in collisions of precipitating particles and production of non-thermal atmospheric atoms and molecules, is reported with analytic fitting equations. Three-dimensional MC simulations with accurate energy-angular-dependent cross sections have been carried out to track large ensembles of energetic atoms in a time-dependent manner as they propagate into the Martian atmosphere and transfer their energy to the ambient atoms and molecules. Results of the MC simulations on the energy-deposition altitude profiles, reflection coefficients, and time-dependent atmospheric heating, obtained for the isotropic hard sphere and anisotropic quantum cross sections, are compared. Atmospheric heating rates, thermalization depths, altitude profiles of production rates, energy distributions of SH atoms and molecules, and induced escape fluxes have been determined.

  13. HYDROCEPHALUS IN THREE JUVENILE NORTH AMERICAN BLACK BEARS (URSUS AMERICANUS).

    Science.gov (United States)

    Ferguson, Sylvia H; Novak, Janelle; Hecht, Silke; Craig, Linden E

    2016-06-01

    Hydrocephalus has been reported in a variety of species, including the North American black bear ( Ursus americanus ). This report describes three cases of hydrocephalus in this species from wild bears aged 3-4 mo considered retrospectively from necropsy records of one institution. Clinical signs included cortical blindness and ataxia. Primary gross findings were doming of the skull, gyri compression and flattening, and lateral ventricle dilation. Two cases had severe bilateral ventricular dilation with loss of the septum pellucidum; atrophy of the surrounding corpus callosum; and bilateral periventricular tears involving the caudate nuclei, internal capsule, and adjacent cerebrum. Histologically, the cases with periventricular tearing had severe axonal loss and degeneration, malacia, hemorrhage, and variable periventricular astrocytosis. All cases were likely congenital, given the bears' age and lack of an apparent acquired obstruction. PMID:27468040

  14. Glucose uptake and glycogen synthesis in adult Necator americanus

    International Nuclear Information System (INIS)

    The uptake of 14C glucose by N. americanus in Kreb's solution at 37deg C was studied. The results showed that glucose is taken up in the presence of host serum in the incubation medium. The uptake of radioactivity was similar when the incubations were carried out in an atmosphere of oxygen or nitrogen. The parasite was also capable of incorporating glucose into glycogen. No difference in the incorporation was seen when the incubations were carried out in the presence and absence of serum. However incorporation was significantly reduced to 0deg-4deg C. It is concluded that glucose is taken up, gets incorporated into the glycogen and this may be a source of nutrition for the hookworm parasite. (author)

  15. Neutral-pion reactions induced by chiral anomaly in strong magnetic fields

    OpenAIRE

    Hattori, Koichi; Itakura, Kazunori; Ozaki, Sho

    2013-01-01

    We investigate decay and production of neutral pions in strong magnetic fields. In the presence of strong magnetic fields, transition between a neutral pion and a virtual photon becomes possible through the triangle diagram relevant for the chiral anomaly. We find that the decay mode of a neutral pion into two photons cannot persist in the dominant mode in strong magnetic fields, and that decay into a dilepton instead dominates over the other modes. We also investigate the effects of magnetic...

  16. Study of neutral current reactions with production of a pion induced by muon antineutrinos

    International Nuclear Information System (INIS)

    In this work we have studied the 4 production reactions of a pion induced by muon anti-neutrino collisions with nucleons: anti-νμp → anti-νμpπ0 or anti-νμnπ+ and anti-νμn → anti-νμnπ0 or anti-νμpπ-. We have processed experimental data from the Gargamelle cloud chamber to assess the pion production cross-sections. Our results are consistent with the theoretical predictions of the Adler model and of the Fogli and Nardulli model within the framework of the Weinberg and Salam unified theory. As for the isospin structure of the weak hadronic neutral current, the iso-vectorial component is highlighted in the invariant mass spectra in the channels pπ0 and pπ-. Our results show that the isospin structure is not purely isoscalar or purely iso-vectorial but rather a mix of I = 0 and I = 1. We confirm that the sign of the product of the 2 coupling constants uL*dL is negative. (A.C.)

  17. A Measurement of Neutrino-Induced Charged-Current Neutral Pion Production

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Robert H. [Univ. of Colorado, Boulder, CO (United States)

    2010-01-01

    This work presents the first comprehensive measurement of neutrino-induced charged-current neutral pion production (CCπ0) off a nuclear target. The Mini Booster Neutrino Experiment (MiniBooNE) and Booster Neutrino Beam (BNB) are discussed in detail. MiniBooNE is a high-statistics (~ 1, 000, 000 interactions) low-energy (Evϵ 2 0.5 - 2.0 GeV) neutrino experiment located at Fermilab. The method for selecting and reconstructing CCπ0 events is presented. The π0 and μ- are fully reconstructed in the final state allowing for the measurement of, among other things, the neutrino energy. The total observable CCπ0 cross-section is presented as a function of neutrino energy, along with five differential cross-sections in terms of the final state kinematics and Q2. The results are combined to yield a flux-averaged total cross-section of <σ>Φ = (9.2 ± 0.3stat. ± 1.5syst.) × 10-39 cm2/CH2 at energy 965 MeV. These measurements will aid future neutrino experiments with the prediction of their neutrino interaction rates.

  18. A Measurement of Neutrino-Induced Charged-Current Neutral Pion Production

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Robert H.; /Colorado U.

    2010-04-01

    This work presents the first comprehensive measurement of neutrino-induced charged-current neutral pion production (CC{pi}{sup 0}) off a nuclear target. The Mini Booster Neutrino Experiment (MiniBooNE) and Booster Neutrino Beam (BNB) are discussed in detail. MiniBooNE is a high-statistics ({approx} 1,000,000 interactions) low-energy (E{sub {nu}} {element_of} 0.5-2.0 GeV) neutrino experiment located at Fermilab. The method for selecting and reconstructing CC{pi}{sup 0} events is presented. The {pi}{sup 0} and {mu}{sup -} are fully reconstructed in the final state allowing for the measurement of, among other things, the neutrino energy. The total observable CC{pi}{sup 0} cross-section is presented as a function of neutrino energy, along with five differential cross-sections in terms of the final state kinematics and Q{sup 2}. The results are combined to yield a flux-averaged total cross-section of <{sigma}>{sub {Phi}} = (9.2 {+-} 0.3{sub stat.} {+-} 1.5{sub syst}.) x 10{sup -39} cm{sup 2}/CH{sub 2} at energy 965 MeV. These measurements will aid future neutrino experiments with the prediction of their neutrino interaction rates.

  19. A theoretical analysis of parity violation induced by neutral currents in atomic cesium

    Science.gov (United States)

    Bouchiat, C.; Piketty, C. A.; Pignon, D.

    1983-07-01

    In this paper we give a theoretical analysis of the parity violation phenomena in nS - n'S transitions in atomic cesium induced by the electron-nucleus neutral-current interaction. The actual observation of parity violation consists in the measurement of an interference between the p.v. electric dipole amplitude Elpv with the electric amplitude induced by a static electric field. Our theoretical work must then include a calculation of the diagonal and non-diagonal polarizabilities of the states of atomic cesium. We have used a one-electron model proposed by Norcross which incorporates some many-body effects like the electric screening induced by the core polarization in a semi-empirical way. Our calculated values of the diagonal and non-diagonal polarizabilities of the nS states are in good agreement with the existing measurements; this confirms the already well-established success of the model in predicting the radiative transitions in cesium. We present theoretical arguments supported by detailed numerical computations showing that the one-particle matrix element of the parity-violating electron-nucleus interaction and the parity-violating electric dipole amplitude Elpv itself weakly depend on the shape of the one-electron potential provided the binding energies of the valence states are reproduced accurately. Furthermore it turns out that because of a compensation mechanism, the parity-violating transition is induced by the radiation field outside the ion core region where the screening can be described simply in terms of the measurable cesium ion polarizability. Our results are then used to extract, from the Ecole Normale Supérieure experiment, a value of the weak charge Qw = -57.1 ± 9.4 (r.m.s. statistical deviation) ± 4.7 (systematic uncertainty). This number is to be compared with the prediction of the Weinberg-Salam model with electro-weak radiative corrections: Qw = -68.6 ± 3.0. A general discussion of the uncertainties of the atomic physics

  20. Taxonomic recovery of the ant cricket Myrmecophilus albicinctus from M. americanus (Orthoptera, Myrmecophilidae)

    OpenAIRE

    Komatsu, Takashi; Maruyama, Munetoshi

    2016-01-01

    Abstract Myrmecophilus americanus and Myrmecophilus albicinctus are typical myrmecophilous insects living inside ant nests. These species are ecologically important due to the obligate association with tramp ant species, including harmful invasive ant species. However, the taxonomy of these “white-banded ant crickets” is quite confused owing to a scarcity of useful external morphological characteristics. Recently, Myrmecophilus albicinctus was synonymized with Myrmecophilus americanus regardl...

  1. Binding of Excreted and/or Secreted Products of Adult Hookworms to Human NK Cells in Necator americanus-Infected Individuals from Brazil▿

    Science.gov (United States)

    Teixeira-Carvalho, Andréa; Fujiwara, Ricardo T.; Stemmy, Erik J.; Olive, Denise; Damsker, Jesse M.; Loukas, Alex; Corrêa-Oliveira, Rodrigo; Constant, Stephanie L.; Bethony, Jeffrey M.

    2008-01-01

    The impact of the interaction between excreted and/or secreted (ES) Necator americanus products and NK cells from Necator-infected individuals was analyzed. We investigated the binding of ES products to NK cells, the expression of NK cell receptors (CD56, CD159a/NKG2A, CD314/NKG2D, CD335/NKp46, and KLRF1/NKp80), the frequency of gamma interferon (IFN-γ)-producing NK cells after whole-blood in vitro stimulation, and the capacity of N. americanus ES products to induce NK cell chemotaxis. In contrast to those from noninfected individuals, NK cells from Necator-infected individuals demonstrated no binding with N. americanus ES products. This phenomenon was not due to alterations in NK cell receptor expression in infected subjects and could not be reproduced with NK cells from uninfected individuals by incubation with immunoregulatory cytokines (interleukin-10/transforming growth factor β). Further, we found that a significantly greater percentage of NK cells from infected subjects than NK cells from uninfected individuals spontaneously produced IFN-γ upon ex vivo culture. Our findings support a model whereby NK cells from Necator-infected individuals may interact with ES products, making these cells refractory to binding with exogenous ES products. During N. americanus infection, human NK cells are attracted to the site of infection by chemotactic ES products produced by adult Necator worms in the gut mucosa. Binding of ES products causes the NK cells to become activated and secrete IFN-γ locally, thereby contributing to the adult hookworm's ability to evade host immune responses. PMID:18838519

  2. Laser Induced Fluorescence Spectroscopy of Neutral and Ionized Polycyclic Aromatic Hydrocarbons in a Cosmic Simulation Chamber

    Science.gov (United States)

    Bejaoui, Salma; Salama, Farid

    2015-08-01

    Polycyclic aromatic hydrocarbon (PAH) molecules are considered the best carriers to account for the ubiquitous infrared emission bands. PAHs have also been proposed as candidates to explain the diffuse interstellar bands (DIBs), a series of absorption features seen on the interstellar extinction curve and are plausible carriers for the extended red emission (ERE), a photoluminescent process associated with a wide variety of interstellar environments. Extensive efforts have been devoted over the past two decades to characterize the physical and chemical properties of PAH molecules and ions in space. Absorption spectra of PAH molecules and ions trapped in solid matrices have been compared to the DIBs [1, 2]. Absorption spectra of several cold, isolated gas-phase PAHs have also been measured under experimental conditions that mimic the interstellar conditions [see 3 for a review]. The purpose of this study is to provide a new dimension to the existing spectroscopic database of neutral and single ionized PAHs that is largely based on absorption spectra by adding emission spectroscopy data. The measurements are based on the laser-induced fluorescence (LIF) technique [4] and are performed with the Pulsed Discharge Nozzle (PDN) of the COSmIC laboratory facility at NASA Ames laboratory. The PDN generates plasma in a free supersonic jet expansion to simulate the physical and the chemical conditions in interstellar environments. We focus, here, on the fluorescence spectra of large neutral PAHs and their cations where there is a lack of fluorescence spectroscopy data. The astronomical implications of the data (e.g., ERE) are examinedReferences[1] F. Salama, E. Bakes, L.J. Allamandola, A.G.G.M. Tielens, Astrophys. J., 458 (1996) p.621[2] F. Salama, The ISO Revolution, EDP Sciences, Les Ulis, France (1999) p.65[3] Salama F., In Organic Matter in Space, IAU Symposium 251, Kwok & Sandford Eds.Cambridge University Press,4, S251,(2008), p. 357 (2008) and references therein.[4

  3. Analytical description of a neutral-induced tripole vortex in a plasma

    International Nuclear Information System (INIS)

    An analytical description of a stationary triple vortex, observed in a cylindrical plasma, is presented. The concentration of neutrals, which is rather high in the experiment, turns out to be of crucial importance due to a spatially dependent distribution. In the radial direction the neutral concentration is paraboliclike, yielding an effective radial force directed towards the axis of the system. This neutral force causes the rotation of the plasma in the direction which is opposite to the E→xB drift. The stationary triple vortex develops for a starting Gaussian-density distribution and a rigid-body rotation of the plasma column

  4. Analytical description of a neutral-induced tripole vortex in a plasma.

    Science.gov (United States)

    Vranjes, J; Okamoto, A; Yoshimura, S; Poedts, S; Kono, M; Tanaka, M Y

    2002-12-23

    An analytical description of a stationary triple vortex, observed in a cylindrical plasma, is presented. The concentration of neutrals, which is rather high in the experiment, turns out to be of crucial importance due to a spatially dependent distribution. In the radial direction the neutral concentration is paraboliclike, yielding an effective radial force directed towards the axis of the system. This neutral force causes the rotation of the plasma in the direction which is opposite to the E-->xB--> drift. The stationary triple vortex develops for a starting Gaussian-density distribution and a rigid-body rotation of the plasma column. PMID:12484828

  5. Variability in detection and quantification of interferon β-1b–induced neutralizing antibodies

    Directory of Open Access Journals (Sweden)

    Hartung Hans-Peter

    2012-06-01

    Full Text Available Abstract Background Interferon-beta (IFNB therapy for multiple sclerosis can lead to the induction of neutralizing antibodies (NAbs against IFNB. Various methods are used for detection and quantification of NAbs. Methods Blood samples from 125 IFNB-1b–treated patients, which were tested NAb negative or NAb positive after conclusion of a clinical study, were retested three years after first being assessed in four different laboratories that offer routine NAb testing to practicing neurologists. The myxovirus protein A (MxA induction assay, the cytopathic effect (CPE assay (two laboratories, or the luciferase assay were used. Intra- and inter-laboratory agreement between assays with respect to NAb detection and NAb titer quantification were evaluated. Results High agreement for NAb detection (kappa coefficient, 0.86 and for titer levels was observed for the intra-laboratory comparison in the laboratory using the MxA induction assay performed three years ago and now. A similarly high agreement for NAb detection (kappa coefficient, 0.87 and for titer quantification was noted for the MxA assay of this laboratory with one of two laboratories using the CPE assay. All other inter-laboratory comparisons showed kappa values between 0.57 and 0.68 and remarkable differences in individual titer levels. Conclusions There are considerable differences in the detection and quantification of IFNB-induced NAbs among laboratories offering NAb testing for clinical practice using different assay methods. It is important that these differences are considered when interpreting NAb results for clinical decision-making and when developing general recommendations for potentially clinically meaningful NAb titer levels.

  6. A genetically detoxified derivative of heat-labile Escherichia coli enterotoxin induces neutralizing antibodies against the A subunit

    OpenAIRE

    1994-01-01

    Escherichia coli enterotoxin (LT) and the homologous cholera toxin (CT) are A-B toxins that cause travelers' diarrhea and cholera, respectively. So far, experimental live and killed vaccines against these diseases have been developed using only the nontoxic B portion of these toxins. The enzymatically active A subunit has not been used because it is responsible for the toxicity and it is reported to induce a negligible titer of toxin neutralizing antibodies. We used site- directed mutagenesis...

  7. On the cosmic-ray induced background in neutral pion production measurements with a BaF2 multidetector

    International Nuclear Information System (INIS)

    The problem of the cosmic-ray induced background in neutral pion production measurements with barium fluoride multidetectors is discussed. As a reference example, the response to cosmic rays of the MEDEA photon spectrometer is studied. The interaction of the cosmic radiation with the experimental filter has been treated by means of full Monte Carlo computer simulations with the GEANT3 code. The results of the simulations are compared with experimental data and general criteria to minimize the cosmic background are discussed. ((orig.))

  8. Description-based reappraisal regulate the emotion induced by erotic and neutral images in a Chinese population

    OpenAIRE

    Jiaxin ePeng; Chen eQu; Ruolei eGu; Yue-jia eLuo

    2013-01-01

    Previous emotion-regulation research has shown that the late positive potential (LPP) is sensitive to the down-regulation of emotion; however, whether LPP is also sensitive to the up-regulation of emotion remains unclear. The present study examined the description-based reappraisal effects on the up-regulation of positive emotions induced by erotic and neutral images in a Chinese population. Self-reported ratings and event-related potential (ERP) were recorded when subjects viewed pleasant an...

  9. Neutralizing S1P inhibits intratumoral hypoxia, induces vascular remodelling and sensitizes to chemotherapy in prostate cancer

    OpenAIRE

    Ader, Isabelle; Gstalder, Cécile; Bouquerel, Pierre; Golzio, Muriel; Andrieu, Guillaume; Zalvidea, Santiago; Richard, Sylvain; Sabbadini, Roger A; Malavaud, Bernard; Cuvillier, Olivier

    2015-01-01

    Hypoxia promotes neovascularization, increased tumor growth, and therapeutic resistance. The transcription factor, hypoxia-inducible factor 1α (HIF-1α), has been reported as the master driver of adaptation to hypoxia. We previously identified the sphingosine kinase 1/sphingosine 1-phosphate (SphK1/S1P) pathway as a new modulator of HIF-1α under hypoxia. Taking advantage of a monoclonal antibody neutralizing extracellular S1P (sphingomab), we report that inhibition of S1P extracellular signali...

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

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Colin E. [Yale Univ., New Haven, CT (United States)

    2011-05-01

    Elucidating the nature of neutrino oscillation continues to be a goal in the vanguard of the efforts of physics experiment. As neutrino oscillation searches seek an increasingly elusive signal, a thorough understanding of the possible backgrounds becomes ever more important. Measurements of neutrino-nucleus interaction cross sections are key to this understanding. Searches for νμ → νe oscillation - a channel that may yield insight into the vanishingly small mixing parameter θ13, CP violation, and the neutrino mass hierarchy - are particularly susceptible to contamination from neutral current single π0 (NC 1π0) production. Unfortunately, the available data concerning NC 1π0 production are limited in scope and statistics. Without satisfactory constraints, theoretical models of NC 1π0 production yield substantially differing predictions in the critical Eν ~ 1 GeV regime. Additional investigation of this interaction can ameliorate the current deficiencies. The Mini Booster Neutrino Experiment (MiniBooNE) is a short-baseline neutrino oscillation search operating at the Fermi National Accelerator Laboratory (Fermilab). While the oscillation search is the principal charge of the MiniBooNE collaboration, the extensive data (~ 106 neutrino events) offer a rich resource with which to conduct neutrino cross section measurements. This work concerns the measurement of both neutrino and antineutrino NC 1π0 production cross sections at MiniBooNE. The size of the event samples used in the analysis exceeds that of all other similar experiments combined by an order of magnitude. We present the first measurements of the absolute NC 1π0 cross section as well as the first differential cross sections in both neutrino and antineutrino mode. Specifically, we measure single differential cross sections with respect to pion momentum and pion angle. We find the

  11. Stress-induced sphingolipid signaling: role of type-2 neutral sphingomyelinase in murine cell apoptosis and proliferation.

    Directory of Open Access Journals (Sweden)

    Raphael Devillard

    Full Text Available BACKGROUND: Sphingomyelin hydrolysis in response to stress-inducing agents, and subsequent ceramide generation, are implicated in various cellular responses, including apoptosis, inflammation and proliferation, depending on the nature of the different acidic or neutral sphingomyelinases. This study was carried out to investigate whether the neutral Mg(2+-dependent neutral sphingomyelinase-2 (nSMase2 plays a role in the cellular signaling evoked by TNFalpha and oxidized LDLs, two stress-inducing agents, which are mitogenic at low concentrations and proapoptotic at higher concentrations. METHODOLOGY AND PRINCIPAL FINDINGS: For this purpose, we used nSMase2-deficient cells from homozygous fro/fro (fragilitas ossium mice and nSMase2-deficient cells reconstituted with a V5-tagged nSMase2. We report that the genetic defect of nSMase2 (in fibroblasts from fro/fro mice does not alter the TNFalpha and oxidized LDLs-mediated apoptotic response. Likewise, the hepatic toxicity of TNFalpha is similar in wild type and fro mice, thus is independent of nSMase2 activation. In contrast, the mitogenic response elicited by low concentrations of TNFalpha and oxidized LDLs (but not fetal calf serum requires nSMase2 activation. CONCLUSION AND SIGNIFICANCE: nSMase2 activation is not involved in apoptosis mediated by TNFalpha and oxidized LDLs in murine fibroblasts, and in the hepatotoxicity of TNFalpha in mice, but is required for the mitogenic response to stress-inducing agents.

  12. Novel Adenoviral Vector Induces T Cell Responses Despite Anti-Adenoviral Neutralizing Antibodies in Colorectal Cancer Patients

    OpenAIRE

    Morse, Michael A; Chaudhry, Arvind; Gabitzsch, Elizabeth S; Hobeika, Amy C.; Osada, Takuya; Clay, Timothy M.; Amalfitano, Andrea; Burnett, Bruce K.; Devi, Gayathri R.; Hsu, David S; Xu, Younong; Balcaitis, Stephanie; Dua, Rajesh; Nguyen, Susan; Balint, Joseph P.

    2013-01-01

    First generation, E1-deleted Adenovirus subtype 5 (Ad5)-based vectors, although promising platforms for use as cancer vaccines, are impeded in activity by naturally occurring or induced Ad-specific neutralizing antibodies. Ad5-based vectors with deletions of the E1 and the E2b regions (Ad5 [E1-, E2b-]), the latter encoding the DNA polymerase and the pre-terminal protein, by virtue of diminished late phase viral protein expression, were hypothesized to avoid immunological clearance and induce ...

  13. Neutralization of interleukin-17A delays progression of silica-induced lung inflammation and fibrosis in C57BL/6 mice

    International Nuclear Information System (INIS)

    Silica exposure can cause lung inflammation and fibrosis, known as silicosis. Interleukin-17A (IL-17A) and Th17 cells play a pivotal role in controlling inflammatory diseases. However, the roles of IL-17A and Th17 cells in the progress of silica-induced inflammation and fibrosis are poorly understood. This study explored the effects of IL-17A on silica-induced inflammation and fibrosis. We used an anti-mouse IL-17A antibody to establish an IL-17A-neutralized mice model, and mice were exposed to silica to establish an experimental silicosis model. We showed that IL-17A neutralization delayed neutrophil accumulation and progression of silica-induced lung inflammation and fibrosis. IL-17A neutralization reduced the percentage of Th17 in CD4 + T cells, decreased IL-6 and IL-1β expression, and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A delayed silica-induced Th1/Th2 immune and autoimmune responses. These results suggest that IL-17A neutralization alleviates early stage silica-induced lung inflammation and delays progression of silica-induced lung inflammation and fibrosis. Neutralization of IL-17A suppressed Th17 cell development by decreasing IL-6 and/or IL-1β and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A also delayed the Th1/Th2 immune response during silica-induced lung inflammation and fibrosis. IL-17A may play a pivotal role in the early phase of silica-induced inflammation and may mediate the Th immune response to influence silica-induced lung inflammation and fibrosis in mice. - Highlights: • Neutralization of IL-17A alleviated silica-induced lung inflammation of early stage. • Neutralization of IL-17A decreased Th17 cells and increased Tregs. • IL-17A mediated the reciprocal relationship of Th17/Tregs by IL-6 and/or IL-1β. • Neutralization of IL-17A delayed silica-induced Th1/Th2 immune response. • Neutralization of IL-17A delayed silica-induced lung

  14. Neutralization of interleukin-17A delays progression of silica-induced lung inflammation and fibrosis in C57BL/6 mice

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying; Li, Cuiying [Division of Pneumoconiosis, School of Public Health, China Medical University, Shenyang, Liaoning (China); Weng, Dong [Division of Pneumoconiosis, School of Public Health, China Medical University, Shenyang, Liaoning (China); Clinical Translational Research Center, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai (China); Song, Laiyu; Tang, Wen; Dai, Wujing; Yu, Ye; Liu, Fangwei; Zhao, Ming; Lu, Chunwei [Division of Pneumoconiosis, School of Public Health, China Medical University, Shenyang, Liaoning (China); Chen, Jie, E-mail: chenjie@mail.cmu.edu.cn [Division of Pneumoconiosis, School of Public Health, China Medical University, Shenyang, Liaoning (China)

    2014-02-15

    Silica exposure can cause lung inflammation and fibrosis, known as silicosis. Interleukin-17A (IL-17A) and Th17 cells play a pivotal role in controlling inflammatory diseases. However, the roles of IL-17A and Th17 cells in the progress of silica-induced inflammation and fibrosis are poorly understood. This study explored the effects of IL-17A on silica-induced inflammation and fibrosis. We used an anti-mouse IL-17A antibody to establish an IL-17A-neutralized mice model, and mice were exposed to silica to establish an experimental silicosis model. We showed that IL-17A neutralization delayed neutrophil accumulation and progression of silica-induced lung inflammation and fibrosis. IL-17A neutralization reduced the percentage of Th17 in CD4 + T cells, decreased IL-6 and IL-1β expression, and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A delayed silica-induced Th1/Th2 immune and autoimmune responses. These results suggest that IL-17A neutralization alleviates early stage silica-induced lung inflammation and delays progression of silica-induced lung inflammation and fibrosis. Neutralization of IL-17A suppressed Th17 cell development by decreasing IL-6 and/or IL-1β and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A also delayed the Th1/Th2 immune response during silica-induced lung inflammation and fibrosis. IL-17A may play a pivotal role in the early phase of silica-induced inflammation and may mediate the Th immune response to influence silica-induced lung inflammation and fibrosis in mice. - Highlights: • Neutralization of IL-17A alleviated silica-induced lung inflammation of early stage. • Neutralization of IL-17A decreased Th17 cells and increased Tregs. • IL-17A mediated the reciprocal relationship of Th17/Tregs by IL-6 and/or IL-1β. • Neutralization of IL-17A delayed silica-induced Th1/Th2 immune response. • Neutralization of IL-17A delayed silica-induced lung

  15. Measurement of longitudinal phase space in an accelerated H- beam using a laser-induced neutralization method

    International Nuclear Information System (INIS)

    Laser-induced neutralization of H- ions is a process that can be used to measure the longitudinal phase space of accelerated H- beams. The laser-induced neutralization diagnostic approach (LINDA) measures the longitudinal emittance of an H- beam by photoneutralizing different phase slices of beam microbunches and analyzing the energy distribution of the neutral slices. A LINDA system utilizing a pulsed laser and time-of-flight analysis has successfully measured longitudinal emittance of the 5 MeV H- beam exiting the drift-tube linac of the Los Alamos Accelerator Test Stand. Design considerations associated with the LINDA laser-based emittance measuring system are given. The present LINDA system is described and its limitations are discussed. Experimental results are given from an application of the LINDA system to the measurement of longitudinal emittance growth in a drift space and following insertion into the beamline of beam transport elements comprising a single-arm funnel. A new system is proposed which uses a mode-locked laser and spectrometer to improve resolution and shorten measurement time. (orig.)

  16. Neutralized ion beam modification of cellulose membranes for study of ion charge effect on ion-beam-induced DNA transfer

    Energy Technology Data Exchange (ETDEWEB)

    Prakrajang, K., E-mail: k.prakrajang@gmail.com [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Sangwijit, K.; Anuntalabhochai, S. [Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Wanichapichart, P. [Membrane Science and Technology Research Center, Department of Physics, Faculty of Science, Prince of Songkla University, Hat Yai, Songkla 90110 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2012-02-01

    Low-energy ion beam biotechnology (IBBT) has recently been rapidly developed worldwide. Ion-beam-induced DNA transfer is one of the important applications of IBBT. However, mechanisms involved in this application are not yet well understood. In this study plasma-neutralized ion beam was applied to investigate ion charge effect on induction of DNA transfer. Argon ion beam at 7.5 keV was neutralized by RF-driven plasma in the beam path and then bombarded cellulose membranes which were used as the mimetic plant cell envelope. Electrical properties such as impedance and capacitance of the membranes were measured after the bombardment. An in vitro experiment on plasmid DNA transfer through the cellulose membrane was followed up. The results showed that the ion charge input played an important role in the impedance and capacitance changes which would affect DNA transfer. Generally speaking, neutral particle beam bombardment of biologic cells was more effective in inducing DNA transfer than charged ion beam bombardment.

  17. The complete genome sequence of 'Candidatus Liberibacter americanus', associated with Citrus huanglongbing.

    Science.gov (United States)

    Wulff, Nelson A; Zhang, Shujian; Setubal, João C; Almeida, Nalvo F; Martins, Elaine C; Harakava, Ricardo; Kumar, Dibyendu; Rangel, Luiz Thiberio; Foissac, Xavier; Bové, Joseph M; Gabriel, Dean W

    2014-02-01

    Liberibacter spp. form a Rhizobiaceae clade of phloem-limited pathogens of limited host range. Two obligately parasitic species have been sequenced: 'Candidatus Liberibacter asiaticus', which causes citrus huanglongbing (HLB) worldwide, and 'Ca. L. solanacearum', which causes potato "zebra chip" disease. A third (proposed) species, Liberibacter crescens, was isolated from mountain papaya, grown in axenic culture, and sequenced. In an effort to identify common host determinants, the complete genomic DNA sequence of a second HLB species, 'Ca. L. americanus' strain 'São Paulo' was determined. The circular genome of 1,195,201 bp had an average 31.12% GC content and 983 predicted protein encoding genes, 800 (81.4%) of which had a predicted function. There were 658 genes common to all sequenced Liberibacter spp. and only 8 genes common to 'Ca. L. americanus' and 'Ca. L. asiaticus' but not found in 'Ca. L. solanacearum'. Surprisingly, most of the lipopolysaccharide biosynthetic genes were missing from the 'Ca. L. americanus' genome, as well as OmpA and a key regulator of flagellin, all indicating a 'Ca. L. americanus' strategy of avoiding production of major pathogen-associated molecular patterns present in 'Ca. L. asiaticus' and 'Ca. L. solanacearum'. As with 'Ca. L. asiaticus', one of two 'Ca. L. americanus' prophages replicated as an excision plasmid and carried potential lysogenic conversion genes that appeared fragmentary or degenerated in 'Ca. L. solanacearum'. PMID:24200077

  18. Charging Induced Emission of Neutral Atoms from NaCl Nanocube Corners

    OpenAIRE

    Ceresoli, Davide; Zykova-Timan, Tatyana; Tosatti, Erio

    2008-01-01

    Detachment of neutral cations/anions from solid alkali halides can in principle be provoked by donating/subtracting electrons to the surface of alkali halide crystals, but generally constitutes a very endothermic process. However, the amount of energy required for emission is smaller for atoms located in less favorable positions, such as surface steps and kinks. For a corner ion in an alkali halide cube the binding is the weakest, so it should be easier to remove that atom, once it is neutral...

  19. Neutral Current $\

    CERN Document Server

    Chauhan, S; Singh, S K

    2011-01-01

    We calculate cross sections for the neutral current induced neutrino/antineutrino reaction from $^{208}Pb$ target and applied it to study Supernova neutrino event rates. The calculations are done in local density approximation taking into account Pauli blocking, Fermi motion effects and renormalization of weak transition strengths in the nuclear medium. The numerical results for the neutrino nucleus total cross sections have been averaged over the various Supernova neutrino/antineutrino fluxes available in literature.

  20. Human Monoclonal Antibodies against West Nile Virus Induced by Natural Infection Neutralize at a Postattachment Step

    NARCIS (Netherlands)

    Vogt, Matthew R.; Moesker, Bastiaan; Goudsmit, Jaap; Jongeneelen, Mandy; Austin, S. Kyle; Oliphant, Theodore; Nelson, Steevenson; Pierson, Theodore C.; Wilschut, Jan; Throsby, Mark; Diamond, Michael S.

    2009-01-01

    West Nile virus (WNV) is a neurotropic flavivirus that is now a primary cause of epidemic encephalitis in North America. Studies of mice have demonstrated that the humoral immune response against WNV limits primary infection and protects against a secondary challenge. The most-potent neutralizing mo

  1. Vaccine-induced cross-genotype reactive neutralizing antibodies against hepatitis C virus

    DEFF Research Database (Denmark)

    Meunier, Jean-Christophe; Gottwein, Judith M; Houghton, Michael; Russell, Rodney S; Emerson, Suzanne U; Bukh, Jens; Purcell, Robert H

    2011-01-01

    We detected cross-reactive neutralizing antibodies (NtAb) against hepatitis C virus (HCV) in chimpanzees vaccinated with HCV-1 (genotype 1a) recombinant E1/E2 envelope glycoproteins. Five vaccinated chimpanzees, protected following HCV-1 challenge, were initially studied using the heterologous H77...

  2. Numerical validation of axial plasma momentum lost to a lateral wall induced by neutral depletion

    Energy Technology Data Exchange (ETDEWEB)

    Takao, Yoshinori, E-mail: takao@ynu.ac.jp [Division of Systems Research, Yokohama National University, Yokohama 240-8501 (Japan); Takahashi, Kazunori [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2015-11-15

    Momentum imparted to a lateral wall of a compact inductively coupled plasma thruster is numerically investigated for argon and xenon gases by a particle-in-cell simulation with Monte Carlo collisions (PIC-MCC). Axial plasma momentum lost to a lateral wall is clearly shown when axial depletion of the neutrals is enhanced, which is in qualitative agreement with the result in a recent experiment using a helicon plasma source [Takahashi et al., Phys. Rev. Lett. 114, 195001 (2015)]. The PIC-MCC calculations demonstrate that the neutral depletion causes an axially asymmetric profile of the plasma density and potential, leading to axial ion acceleration and the non-negligible net axial force exerted to the lateral wall in the opposite direction of the thrust.

  3. Impurity induced neutralization of MeV energy protons in JET plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Gondhalekar, A. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Korotkov, A.A. [AF Ioffe Institute, Saint Petersburg (Russian Federation)

    1994-07-01

    A model elucidating the role of carbon and beryllium, the main impurities in JET plasmas, in neutralizing MeV energy protons, which arise during ICRF heating of deuterium plasmas in the hydrogen minority heating mode D(H), and from D-D fusion reactions, is presented. The model establishes charge transfer from hydrogen-like impurity ions to protons as the main process for neutralization. Calculations for deducing the proton energy distribution function from measured hydrogen flux are described. The validity of the model is tested by using it to described the measured flux in different conditions of plasma heating and fueling. Further, it is used to deduce the background thermal deuterium atom density at the plasma center. 9 refs., 6 figs.

  4. Multi critical point structure for chiral phase transition induce by charge neutrality and vector interaction

    CERN Document Server

    Zhang, Zhao

    2010-01-01

    The combined effect of the repulsive vector interaction and the positive electric chemical potential on the chiral phase transition is investigated by considering neutral color superconductivity. Under the charge-neutrality constraint, the chiral condensate, diquark condensate and quark number densities are obtained in two-plus-one-flavor Nambu-Jona-Lasinio model with the so called Kobayashi-Maskawa-'t Hooft term. We demonstrate that multiple chiral critical-point structures always exist in the Nambu-Jona-Lasinio model within the self-consistent mean-field approximation, and that the number of chiral critical points can vary from zero to four, which is dependent on the magnitudes of vector interaction and the diquark coupling.

  5. Systematic experiments on the mismatch induced halo formation using non-neutral electron plasmas in a uniform magnetic field

    International Nuclear Information System (INIS)

    Non-neutral electron plasmas confined in a uniform magnetic field can be used to simulate a beam dynamics in a uniform focusing channel. Here, a halo formation due to a mismatch induced on an electric confinement potential (harmonic potential) is reported. A beam halo is measured with a conventional beam imaging system composed of a phosphor screen and a charge-coupled device (CCD) camera. Obtained results show that the growth rate of a halo is a few tens microseconds in the present experimental condition. (author)

  6. Recombinant Outer Capsid Glycoprotein (VP7 of Rotavirus Expressed in Insect Cells Induces Neutralizing Antibodies in Rabbits

    Directory of Open Access Journals (Sweden)

    H Keyvani

    2012-04-01

    Full Text Available Background:Rotaviruses cause diarrhea in infants and young children worldwide. Rotavirus outer capsid protein, VP7 is major neutralizing antigen that is important component of subunit vaccine to prevent rotavirus infection.Many efforts have been done to produce recombinant VP7 that maintain native characteristics.We used baculovirus expression system to produce rotavirus VP7 protein and to study its immunogenicity. Methods: Simian rotavirus SA11 full-length VP7 ORF was cloned into a cloning plasmid and then the cloned gene was inserted into the linear DNA of baculovirus Autographa californica Nuclear Polyhedrosis Virus (AcNPV downstream of the polyhedrin promoter by in vitro recombination reactions. The expressed VP7 in the insect cells was recognized by rabbit hyperimmune serum raised against SA11 rotavirus by Immunofluorescence and western blotting assays. Rabbits were immunized subcutaneously by cell extracts expressing VP7 protein. Results: Reactivity with anti-rotavirus antibody suggested that expressed VP7 protein had native antigenic determinants.Injection of recombinant VP7 in rabbits elicited the production of serum antibodies,which were able to recognize VP7 protein from SA11 rotavirus by Western blotting test and neutralized SA11 rotavirus in cell culture.Conclusion: Recombinant outer capsid glycoprotein (VP7 of rotavirus expressed in insect cells induces neutralizing antibodies in rabbits and may be a candidate of rotavirus vaccine.

  7. Rapid assessment of antibody-induced ricin neutralization by employing a novel functional cell-based assay.

    Science.gov (United States)

    Gal, Yoav; Alcalay, Ron; Sabo, Tamar; Noy-Porat, Tal; Epstein, Eyal; Kronman, Chanoch; Mazor, Ohad

    2015-09-01

    Ricin is one of the most potent and lethal toxins known against which there is no available antidote. Currently, the most promising countermeasures against the toxin are based on neutralizing antibodies elicited by active vaccination or administered passively. A cell-based assay is widely applied for the primary screening and evaluation of anti-ricin antibodies, yet such assays are usually time-consuming (18-72 h). Here, we report of a novel assay to monitor ricin activity, based on HeLa cells that stably express the rapidly-degraded ubiquitin-luciferase (Ub-FL, half-life of 2 min). Ricin-induced arrest of protein synthesis could be quantified within 3 to 6h post intoxication (IC90 of 300 and 100 ng/ml, respectively). Furthermore, by stabilizing the intracellular levels of Ub-FL in the last hour of the assay, a 3-fold increase in the assay sensitivity was attained. We applied this assay to monitor the efficacy of a ricin holotoxin-based vaccine by measuring the formation of neutralizing antibodies throughout the immunization course. The potency of anti-ricin monoclonal antibodies (directed to either subunit of the toxin) could also be easily and accurately measured in this assay format. Owing to its simplicity, this assay may be implemented for high-throughput screening of ricin-neutralizing antibodies and for identification of small-molecule inhibitors of the toxin, as well as other ribosome-inactivating toxins. PMID:26003675

  8. Neutralization of Japanese Encephalitis Virus by heme-induced broadly reactive human monoclonal antibody

    OpenAIRE

    Nimesh Gupta; Mélissanne de Wispelaere; Maxime Lecerf; Manjula Kalia; Tobias Scheel; Sudhanshu Vrati; Claudia Berek; Kaveri, Srinivas V.; Philippe Desprès; Sébastien Lacroix-Desmazes; Dimitrov, Jordan D.

    2015-01-01

    International audience Geographical expansion and re-emerging new genotypes of the Japanese encephalitis virus (JEV) require the development of novel therapeutic approaches. Here, we studied a non-conventional approach for antibody therapy and show that, upon exposure to heme, a fraction of natural human immunoglobulins acquires high-affinity reactivity with the antigenic domain-III of JEV E glycoprotein. These JEV-reactive antibodies exhibited neutralizing activity against recently domina...

  9. Estimation of neutral-beam-induced field reversal in MFTF by an approximate scaling law

    Energy Technology Data Exchange (ETDEWEB)

    Shearer, J.W.

    1980-04-28

    Scaling rules are derived for field-reversed plasmas whose dimensions are common multiples of the ion gyroradius in the vacuum field. These rules are then applied to the tandem MFTF configuration, and it is shown that field reversal appears to be possible for neutral beam currents of the order of 150 amperes, provided that the electron temperature is at least 500 eV.

  10. Effect of Surface Charge on Laser-induced Neutral Atom Desorption

    International Nuclear Information System (INIS)

    When an ionic metal oxide crystal is cleaved, inhomogeneous electrical charging of the surface can be a result. Such an effect has been well-documented in magnesium oxide (100). For example, recent rigorous AFM studies indicate that nanoscale charged clusters of MgO are created during cleavage, with high concentrations often located at terrace step edges.(1) In addition, ablation processes of freshly cleaved magnesium oxide crystals may be effected by remnant surface charging and microstructures.(2) We report here that such surface charging strongly impacts even neutral atom desorption, even under conditions of extremely mild excitation of surface terrace features. In our experiments, single crystal MgO (100) is cleaved in air and placed in an ultra-high vacuum chamber (UHV). We irradiate the crystal at 6.4 eV, photon energy resonant with five-coordinated (5-C) terrace sites and probe desorbing neutral oxygen atoms. It is found that a significant fraction of desorbed neutral oxygen atoms from the charged surface possess kinetic energies in excess of 0.7 eV. This is in contrast to uncharged samples (discharged in vacuo over 24 hours) that display a near-thermal oxygen atom distribution.

  11. Vaccine-Induced Antibodies that Neutralize Group 1 and Group 2 Influenza A Viruses.

    Science.gov (United States)

    Joyce, M Gordon; Wheatley, Adam K; Thomas, Paul V; Chuang, Gwo-Yu; Soto, Cinque; Bailer, Robert T; Druz, Aliaksandr; Georgiev, Ivelin S; Gillespie, Rebecca A; Kanekiyo, Masaru; Kong, Wing-Pui; Leung, Kwanyee; Narpala, Sandeep N; Prabhakaran, Madhu S; Yang, Eun Sung; Zhang, Baoshan; Zhang, Yi; Asokan, Mangaiarkarasi; Boyington, Jeffrey C; Bylund, Tatsiana; Darko, Sam; Lees, Christopher R; Ransier, Amy; Shen, Chen-Hsiang; Wang, Lingshu; Whittle, James R; Wu, Xueling; Yassine, Hadi M; Santos, Celia; Matsuoka, Yumiko; Tsybovsky, Yaroslav; Baxa, Ulrich; Mullikin, James C; Subbarao, Kanta; Douek, Daniel C; Graham, Barney S; Koup, Richard A; Ledgerwood, Julie E; Roederer, Mario; Shapiro, Lawrence; Kwong, Peter D; Mascola, John R; McDermott, Adrian B

    2016-07-28

    Antibodies capable of neutralizing divergent influenza A viruses could form the basis of a universal vaccine. Here, from subjects enrolled in an H5N1 DNA/MIV-prime-boost influenza vaccine trial, we sorted hemagglutinin cross-reactive memory B cells and identified three antibody classes, each capable of neutralizing diverse subtypes of group 1 and group 2 influenza A viruses. Co-crystal structures with hemagglutinin revealed that each class utilized characteristic germline genes and convergent sequence motifs to recognize overlapping epitopes in the hemagglutinin stem. All six analyzed subjects had sequences from at least one multidonor class, and-in half the subjects-multidonor-class sequences were recovered from >40% of cross-reactive B cells. By contrast, these multidonor-class sequences were rare in published antibody datasets. Vaccination with a divergent hemagglutinin can thus increase the frequency of B cells encoding broad influenza A-neutralizing antibodies. We propose the sequence signature-quantified prevalence of these B cells as a metric to guide universal influenza A immunization strategies. PMID:27453470

  12. DCP-LA neutralizes mutant amyloid beta peptide-induced impairment of long-term potentiation and spatial learning.

    Science.gov (United States)

    Nagata, Tetsu; Tomiyama, Takami; Tominaga, Takemi; Mori, Hiroshi; Yaguchi, Takahiro; Nishizaki, Tomoyuki

    2010-01-01

    Long-term potentiation (LTP) was monitored from the CA1 region of the intact rat hippocampus by delivering high frequency stimulation (HFS) to the Schaffer collateral commissural pathway. Intraventricular injection with mutant amyloid beta(1-42) peptide lacking glutamate-22 (Abeta(1-42)E22Delta), favoring oligomerization, 10 min prior to HFS, inhibited expression of LTP, with the potency more than wild-type amyloid beta(1-42) peptide. Intraperitoneal injection with the linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) 70 min prior to HFS neutralized mutant Abeta(1-42)E22Delta peptide-induced LTP inhibition. In the water maze test, continuous intraventricular injection with mutant Abeta(1-42)E22Delta peptide for 14 days prolonged the acquisition latency as compared with that for control, with the potency similar to wild-type Abeta(1-42) peptide, and intraperitoneal injection with DCP-LA shortened the prolonged latency to control levels. The results of the present study indicate that DCP-LA neutralizes mutant Abeta(1-42)E22Delta peptide-induced impairment of LTP and spatial learning. PMID:19716848

  13. Motivationally Neutral Stimulation of the Nucleus Basalis Induces Specific Behavioral Memory

    OpenAIRE

    Miasnikov, Alexandre A.; Chen, Jemmy C.; Gross, Nataliya; Poytress, Bonnie S.; Weinberger, Norman M.

    2008-01-01

    The cholinergic system has been implicated in learning and memory. The nucleus basalis (NB) provides acetylcholine (ACh) to the cerebral cortex. Pairing a tone with NB stimulation (NBstm) to alter cortical state induces both associative specific tuning plasticity in the primary auditory cortex (A1) and associative specific auditory behavioral memory. NB-induced memory has major features of natural memory that is induced by pairing a tone with motivational reinforcers, e.g., food or shock, sug...

  14. Stress-induced neutral lipid biosynthesis in microalgae - Molecular, cellular and physiological insights.

    Science.gov (United States)

    Zienkiewicz, Krzysztof; Du, Zhi-Yan; Ma, Wei; Vollheyde, Katharina; Benning, Christoph

    2016-09-01

    Photosynthetic microalgae have promise as biofuel feedstock. Under certain conditions, they produce substantial amounts of neutral lipids, mainly in the form of triacylglycerols (TAGs), which can be converted to fuels. Much of our current knowledge on the genetic and molecular basis of algal neutral lipid metabolism derives mainly from studies of plants, i.e. seed tissues, and to a lesser extent from direct studies of algal lipid metabolism. Thus, the knowledge of TAG synthesis and the cellular trafficking of TAG precursors in algal cells is to a large extent based on genome predictions, and most aspects of TAG metabolism have yet to be experimentally verified. The biofuel prospects of microalgae have raised the interest in mechanistic studies of algal TAG biosynthesis in recent years and resulted in an increasing number of publications on lipid metabolism in microalgae. In this review we summarize the current findings on genetic, molecular and physiological studies of TAG accumulation in microalgae. Special emphasis is on the functional analysis of key genes involved in TAG synthesis, molecular mechanisms of regulation of TAG biosynthesis, as well as on possible mechanisms of lipid droplet formation in microalgal cells. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. PMID:26883557

  15. SARCOCYSTIS URSUSI, N. SP (APICOMPLEXA; SARCOCYSTIDAE) FROM THE BLACK BEAR (URSUS AMERICANUS)

    Science.gov (United States)

    Infection with Sarcocystis species is common in hervibores but is rare in bears. Histological sections of 374 black bears (Ursus americanus) from Pennsylvania were examined for sarcocysts. A total of 3 sarcocysts were found in 3 bears, 1 sarcocyst per section. Sarcocysts from 2 bears were considered...

  16. Single photon production induced by (anti)neutrino neutral current scattering on nucleons and nuclear targets

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Ruso, L.; Nieves, J. [Instituto de Física Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigación de Paterna, E-46071 Valencia (Spain); Wang, E. [Instituto de Física Corpuscular (IFIC), Centro Mixto CSIC-Universidad de Valencia, Institutos de Investigación de Paterna, E-46071 Valencia (Spain); Department of Physics, Zhengzhou University, Zhengzhou, Henan 450001 (China)

    2015-10-15

    We review our theoretical approach to neutral current photon emission on nucleons and nuclei in the few-GeV energy region, relevant for neutrino oscillation experiments. These reactions are dominated by the weak excitation of the Δ(1232) resonance but there are also important non-resonant contributions. We have also included terms mediated by nucleon excitations from the second resonance region. On nuclei, Pauli blocking, Fermi motion and the in-medium Δ resonance broadening have been taken into account for both incoherent and coherent reaction channels. With this model, the number and distributions of photon events at the MiniBooNE and T2K experiments have been obtained. We have also compared to the NOMAD upper limit at higher energies. The implications of our findings and future perspectives are discussed.

  17. Single photon production induced by (anti)neutrino neutral current scattering on nucleons and nuclear targets

    International Nuclear Information System (INIS)

    We review our theoretical approach to neutral current photon emission on nucleons and nuclei in the few-GeV energy region, relevant for neutrino oscillation experiments. These reactions are dominated by the weak excitation of the Δ(1232) resonance but there are also important non-resonant contributions. We have also included terms mediated by nucleon excitations from the second resonance region. On nuclei, Pauli blocking, Fermi motion and the in-medium Δ resonance broadening have been taken into account for both incoherent and coherent reaction channels. With this model, the number and distributions of photon events at the MiniBooNE and T2K experiments have been obtained. We have also compared to the NOMAD upper limit at higher energies. The implications of our findings and future perspectives are discussed

  18. Diffuse traumatic axonal injury in mice induces complex behavioural alterations that are normalized by neutralization of interleukin-1β.

    Science.gov (United States)

    Ekmark-Lewén, Sara; Flygt, Johanna; Fridgeirsdottir, Gudrun A; Kiwanuka, Olivia; Hånell, Anders; Meyerson, Bengt J; Mir, Anis K; Gram, Hermann; Lewén, Anders; Clausen, Fredrik; Hillered, Lars; Marklund, Niklas

    2016-04-01

    Widespread traumatic axonal injury (TAI) results in brain network dysfunction, which commonly leads to persisting cognitive and behavioural impairments following traumatic brain injury (TBI). TBI induces a complex neuroinflammatory response, frequently located at sites of axonal pathology. The role of the pro-inflammatory cytokine interleukin (IL)-1β has not been established in TAI. An IL-1β-neutralizing or a control antibody was administered intraperitoneally at 30 min following central fluid percussion injury (cFPI), a mouse model of widespread TAI. Mice subjected to moderate cFPI (n = 41) were compared with sham-injured controls (n = 20) and untreated, naive mice (n = 9). The anti-IL-1β antibody reached the target brain regions in adequate therapeutic concentrations (up to ~30 μg/brain tissue) at 24 h post-injury in both cFPI (n = 5) and sham-injured (n = 3) mice, with lower concentrations at 72 h post-injury (up to ~18 μg/g brain tissue in three cFPI mice). Functional outcome was analysed with the multivariate concentric square field (MCSF) test at 2 and 9 days post-injury, and the Morris water maze (MWM) at 14-21 days post-injury. Following TAI, the IL-1β-neutralizing antibody resulted in an improved behavioural outcome, including normalized behavioural profiles in the MCSF test. The performance in the MWM probe (memory) trial was improved, although not in the learning trials. The IL-1β-neutralizing treatment did not influence cerebral ventricle size or the number of microglia/macrophages. These findings support the hypothesis that IL-1β is an important contributor to the processes causing complex cognitive and behavioural disturbances following TAI. PMID:27091435

  19. An Improved Measurement of Mixing-induced CP Violation in the Neutral B Meson System

    CERN Document Server

    Abe, K; Abe, N; Abe, R; Abe, T; Adachi, I; Ahn, B S; Aihara, H; Akatsu, M; Asai, M; Asano, Y; Aso, T; Aulchenko, V M; Aushev, T; Bakich, A M; Ban, Y; Banas, E; Banerjee, S; Bay, A; Bedny, I; Behera, P K; Beiline, D; Bizjak, I; Bondar, A; Bozek, A; Bracko, M; Brodzicka, J; Browder, T E; Casey, B C K; Chang, M C; Chang, P; Chao, Y; Chen, K F; Cheon, B G; Chistov, R; Choi, S K; Choi, Y; Choi, Y K; Danilov, M; Dong, L Y; Dowd, R; Dragic, J; Drutskoy, A; Eidelman, S; Eiges, V; Enari, Y; Everton, C W; Fang, F; Fujii, H; Fukunaga, C; Gabyshev, N I; Garmash, A; Gershon, T J; Golob, B; Gordon, A; Gotow, K; Guler, H; Guo, R; Haba, J; Hanagaki, K; Handa, F; Hara, K; Hara, T; Harada, Y; Hashimoto, K; Hastings, N C; Hayashii, H; Hazumi, M; Heenan, E M; Higuchi, I; Higuchi, T; Hinz, L; Hirai, T; Hojo, T; Hokuue, T; Hoshi, Y; Hoshina, K; Hou Wei Shu; Hsu, S C; Huang, H C; Igaki, T; Igarashi, Y; Iijima, T; Inami, K; Ishikawa, A; Ishino, H; Itoh, R; Iwamoto, M; Iwasaki, H; Iwasaki, Y; Jackson, D J; Jalocha, P; Jang, H K; Jones, M; Kagan, R; Kakuno, H; Kaneko, J; Kang, J H; Kang, J S; Kapusta, P; Kataoka, M; Kataoka, S U; Katayama, N; Kawai, H; Kawakami, Y; Kawamura, N; Kawasaki, T; Kichimi, H; Kim, D W; Kim, H; Kim, H J; Kim, H O; Kim, S K; Kim, T H; Kinoshita, K; Kobayashi, S; Koishi, S; Korotushenko, K; Korpar, S; Krizan, P; Krokovnyi, P P; Kulasiri, R; Kumar, S; Kurihara, E; Kuzmin, A; Kwon, Y J; Lange, J S; Leder, Gerhard; Lee, S H; Li, J; Limosani, A; Liventsev, D; Lu, R S; MacNaughton, J; Majumder, G; Mandl, F; Marlow, D; Matsubara, T; Matsuishi, T; Matsumoto, S; Matsumoto, T; Mikami, Y; Mitaroff, Winfried A; Miyabayashi, K; Miyabayashi, Y; Miyake, H; Miyata, H; Moffitt, L C; Moloney, G R; Moorhead, G F; Mori, S; Mori, T; Murakami, A; Nagamine, T; Nagasaka, Y; Nakadaira, T; Nakamura, T; Nakano, E; Nakao, M; Nakazawa, H; Nam, J W; Narita, S; Natkaniec, Z; Neichi, K; Nishida, S; Nitoh, O; Noguchi, S; Nozaki, T; Ofuji, A; Ogawa, S; Ohno, F; Ohshima, T; Ohshima, Y; Okabe, T; Okuno, S; Olsen, S L; Onuki, Y; Ostrowicz, W; Ozaki, H; Pakhlov, P; Palka, H; Park, C W; Park, H; Park, K S; Peak, L S; Perroud, Jean-Pierre; Peters, M; Piilonen, L E; Prebys, E J; Rodríguez, J L; Ronga, F J; Root, N; Rózanska, M; Rybicki, K; Ryuko, J; Sagawa, H; Saitoh, S; Sakai, Y; Sakamoto, H; Sakaue, H; Satapathy, M; Satpathy, A; Schneider, O; Schrenk, S; Schwanda, C; Semenov, S; Senyo, K; Settai, Y; Seuster, R; Sevior, M E; Shibuya, H; Shimoyama, M; Shwartz, B A; Sidorov, A; Sidorov, V; Singh, J B; Soni, N; Stanic, S; Staric, M; Sugi, A; Sugiyama, A; Sumisawa, K; Sumiyoshi, T; Suzuki, K; Suzuki, S; Suzuki, S Y; Swain, S K; Takahashi, T; Takasaki, F; Tamai, K; Tamura, N; Tanaka, J; Tanaka, M; Taylor, G N; Teramoto, Y; Tokuda, S; Tomoto, M; Tomura, T; Tovey, Stuart N; Trabelsi, K; Trischuk, W; Tsuboyama, T; Tsukamoto, T; Uehara, S; Ueno, K; Unno, Y; Uno, S; Ushiroda, Y; Vahsen, S E; Varner, G; Varvell, K E; Wang Chao Cheng; Wang, C H; Wang, J G; Wang, M Z; Watanabe, Y; Won, E; Yabsley, B D; Yamada, Y; Yamaguchi, A; Yamamoto, H; Yamanaka, T; Yamashita, Y; Yamauchi, M; Yanai, H; Yanaka, S; Yashima, J; Yeh, P; Yokoyama, M; Yoshida, K; Yuan, Y; Yusa, Y; Yuta, H; Zhang, C C; Zhang, J; Zhang, Z P; Zheng, Y; Zhilich, V N; Zhu, Z M

    2002-01-01

    We present an improved measurement of the standard model CP violation parameter sin2phi_1 (also known as sin2beta) based on a sample of 85 times 10^6 B Bbar pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. One neutral B meson is reconstructed in a J/psi K_S, psi(2S) K_S, chi_{c1} K_S, eta_c K_S, J/psi K^{*0}, or J/psi K_L CP-eigenstate decay channel and the flavor of accompanying B meson is identified from itsdecay products. From the asymmetry in the distribution of the time intervals between the two B meson decay points, we obtain sin2phi_1 = 0.719 +/- 0.074(stat) +/- 0.035(syst). We also report measurements of CP violation parameters for the related B^0 -> J/psi pi^0 decay mode and the penguin-dominated processes B^0 -> eta' K_S, phi K_S and K^+K^- K_S.

  20. Limited Neutrality

    DEFF Research Database (Denmark)

    Nielsen, Morten Ebbe Juul

    2006-01-01

    Article Concerning the prospect of a kind of limited neutrality in place of the standard liberal egalitarian "neutrality of justification."......Article Concerning the prospect of a kind of limited neutrality in place of the standard liberal egalitarian "neutrality of justification."...

  1. Recombinant E2 glycoprotein of bovine viral diarrhea virus induces a solid humoral neutralizing immune response but fails to confer total protection in cattle

    Directory of Open Access Journals (Sweden)

    S. Chimeno Zoth

    2007-06-01

    Full Text Available Two recombinant baculoviruses were produced in order to obtain a bovine viral diarrhea virus (BVDV immunogen: AcNPV/E2 expressing E2 glycoprotein, and AcNPV/E0E1E2 expressing the polyprotein region coding for the three structural proteins of BVDV (E0, E1, and E2. Mice were immunized with Sf9 cells infected with the recombinant baculoviruses in a water in oil formulation and the production of neutralizing antibodies was evaluated. Since E2 elicited higher neutralizing antibody titers than E0-E1-E2 polyprotein, it was selected to immunize cattle. Calves received two doses of recombinant E2 vaccine and were challenged with homologous BVDV 37 days later. The recombinant immunogen induced neutralizing titers which showed a mean value of 1.5 ± 0.27 on the day of challenge and reached a top value of 3.36 ± 0.36, 47 days later (84 days post-vaccination. On the other hand, sera from animals which received mock-infected Sf9 cells did not show neutralizing activity until 25 days post-challenge (62 days post-vaccination, suggesting that these antibodies were produced as a consequence of BVDV challenge. Even when no total protection was observed in cattle, in vitro viral neutralization assays revealed that the recombinant immunogen was able to induce neutralizing antibody synthesis against the homologous strain as well as against heterologous strains in a very efficient way.

  2. Hyperosmolarity-induced lipid droplet formation depends on ceramide production by neutral sphingomyelinase 2[S

    OpenAIRE

    Robciuc, Alexandra; Hyötyläinen, Tuulia; Jauhiainen, Matti; Holopainen, Juha M.

    2012-01-01

    Hyperosmolarity (HO) imposes a remarkable stress on membranes, especially in tissues in direct contact with the external environment. Our efforts were focused on revealing stress-induced lipid changes that precede the inflammatory cytokine response in human corneal epithelial cells exposed to increasing osmolarity. We used a lipidomic analysis that detected significant and systematic changes in the lipid profile, highly correlated with sodium concentrations in the medium. Ceramides and trigly...

  3. Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies

    International Nuclear Information System (INIS)

    Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection

  4. A DNA vaccine against chikungunya virus is protective in mice and induces neutralizing antibodies in mice and nonhuman primates.

    Directory of Open Access Journals (Sweden)

    Karthik Mallilankaraman

    Full Text Available Chikungunya virus (CHIKV is an emerging mosquito-borne alphavirus indigenous to tropical Africa and Asia. Acute illness is characterized by fever, arthralgias, conjunctivitis, rash, and sometimes arthritis. Relatively little is known about the antigenic targets for immunity, and no licensed vaccines or therapeutics are currently available for the pathogen. While the Aedes aegypti mosquito is its primary vector, recent evidence suggests that other carriers can transmit CHIKV thus raising concerns about its spread outside of natural endemic areas to new countries including the U.S. and Europe. Considering the potential for pandemic spread, understanding the development of immunity is paramount to the development of effective counter measures against CHIKV. In this study, we isolated a new CHIKV virus from an acutely infected human patient and developed a defined viral challenge stock in mice that allowed us to study viral pathogenesis and develop a viral neutralization assay. We then constructed a synthetic DNA vaccine delivered by in vivo electroporation (EP that expresses a component of the CHIKV envelope glycoprotein and used this model to evaluate its efficacy. Vaccination induced robust antigen-specific cellular and humoral immune responses, which individually were capable of providing protection against CHIKV challenge in mice. Furthermore, vaccine studies in rhesus macaques demonstrated induction of nAb responses, which mimicked those induced in convalescent human patient sera. These data suggest a protective role for nAb against CHIKV disease and support further study of envelope-based CHIKV DNA vaccines.

  5. Neutralizing effects of polyvalent antivenom on severe inflammatory response induced by Mesobuthus eupeus scorpion venom

    Directory of Open Access Journals (Sweden)

    Zayerzadeh1 E.

    2014-11-01

    Full Text Available This study evaluated the effects of Mesobuthus eupeus (Me scorpion venom on inflammatory response following injection. Additionally, the present study examined whether immunotherapy at specific time intervals would be effective on inflammatory response after Me venom inoculation. Animals were divided randomly into four groups: the first group received LD50 of venom and the second and third groups of animals; immunotherapy was performed in different time intervals and fourth group was considered as control group. Me venom inoculation is caused respiratory perturbations such as respiratory distress, respiration with open mouth, crepitation and finally respiratory arrest. Me inoculation is resulted in increased pro-inflammatory cytokines including TNF-α and IL-1. Venom injection also induced inflammatory response, characterized by significant increase in serum white blood cells and neutrophils at 30, 60 and 180 min following envenomation. Simultaneous administration of antivenom and venom prevented entirely clinical sings, cytokines and hematological changes. Delayed immunotherapy gradually ameliorated clinical features, cytokines changes and hematological abnormalities related to the envenomation. In conclusion, our observations indicate injection of M. eupeus scorpion venom induces severe inflammatory response which can be one of the causes of clinical complications. Additionally, immunotherapy beyond 1 h after envenomation with appropriate dose and route in victims with severe inflammatory response related to the M.eupeus scorpion envenomation is beneficial.

  6. The complete mitochondrial genome of the American lobster, Homarus americanus (Crustacea, Decapoda).

    Science.gov (United States)

    Kim, Sanghee; Lee, Sang-Hwa; Park, Mi-Hyun; Choi, Han-Gu; Park, Joong-Ki; Min, Gi-Sik

    2011-06-01

    Although relatively a large number of the complete mitochondrial genome sequences have been determined from various decapod species (29 mtDNA sequences reported so far), the information for the infraorder Astacidea (including lobsters, crayfishes, and their relatives) is very limited and represented by only one complete sequence from the Australian freshwater crayfish species Cherax destructor. In this study, we determined the complete mitochondrial DNA sequence of Homarus americanus, the first representative of the family Nephropidae to be fully characterized. Comparison of the gene arrangement reveals that H. americanus mtDNA is identical to those of other pancrustacean species but differs from the other astacidean species (C. destructor). Based on these data, it can be assumed that an idiosyncratic gene order discovered in C. destructor mtDNA may be secondarily acquired from the ancestral lineage of the Astacidea. PMID:21740340

  7. Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Aslan, Mutay, E-mail: mutayaslan@akdeniz.edu.tr [Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya (Turkey); Basaranlar, Goksun [Department of Biophysics, Akdeniz University Faculty of Medicine, Antalya (Turkey); Unal, Mustafa [Department of Ophthalmology, Akdeniz University Faculty of Medicine, Antalya (Turkey); Ciftcioglu, Akif [Department of Pathology, Akdeniz University Faculty of Medicine, Antalya (Turkey); Derin, Narin [Department of Biophysics, Akdeniz University Faculty of Medicine, Antalya (Turkey); Mutus, Bulent [Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario (Canada)

    2014-11-01

    Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension.

  8. High-throughput pseudovirion-based neutralization assay for analysis of natural and vaccine-induced antibodies against human papillomaviruses.

    Directory of Open Access Journals (Sweden)

    Peter Sehr

    Full Text Available A highly sensitive, automated, purely add-on, high-throughput pseudovirion-based neutralization assay (HT-PBNA with excellent repeatability and run-to-run reproducibility was developed for human papillomavirus types (HPV 16, 18, 31, 45, 52, 58 and bovine papillomavirus type 1. Preparation of 384 well assay plates with serially diluted sera and the actual cell-based assay are separated in time, therefore batches of up to one hundred assay plates can be processed sequentially. A mean coefficient of variation (CV of 13% was obtained for anti-HPV 16 and HPV 18 titers for a standard serum tested in a total of 58 repeats on individual plates in seven independent runs. Natural antibody response was analyzed in 35 sera from patients with HPV 16 DNA positive cervical intraepithelial neoplasia grade 2+ lesions. The new HT-PBNA is based on Gaussia luciferase with increased sensitivity compared to the previously described manual PBNA (manPBNA based on secreted alkaline phosphatase as reporter. Titers obtained with HT-PBNA were generally higher than titers obtained with the manPBNA. A good linear correlation (R(2 = 0.7 was found between HT-PBNA titers and anti-HPV 16 L1 antibody-levels determined by a Luminex bead-based GST-capture assay for these 35 sera and a Kappa-value of 0.72, with only 3 discordant sera in the low titer range. In addition to natural low titer antibody responses the high sensitivity of the HT-PBNA also allows detection of cross-neutralizing antibodies induced by commercial HPV L1-vaccines and experimental L2-vaccines. When analyzing the WHO international standards for HPV 16 and 18 we determined an analytical sensitivity of 0.864 and 1.105 mIU, respectively.

  9. Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

    International Nuclear Information System (INIS)

    Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension

  10. Geographical venom variations of the Southeast Asian monocled cobra (Naja kaouthia): venom-induced neuromuscular depression and antivenom neutralization.

    Science.gov (United States)

    Tan, Kae Yi; Tan, Choo Hock; Sim, Si Mui; Fung, Shin Yee; Tan, Nget Hong

    2016-01-01

    The Southeast Asian monocled cobras (Naja kaouthia) exhibit geographical variations in their venom proteomes, especially on the composition of neurotoxins. This study compared the neuromuscular depressant activity of the venoms of N. kaouthia from Malaysia (NK-M), Thailand (NK-T) and Vietnam (NK-V), and the neutralization of neurotoxicity by a monospecific antivenom. On chick biventer cervicis nerve-muscle preparation, all venoms abolished the indirect twitches, with NK-T venom being the most potent (shortest t90, time to 90% twitch inhibition), followed by NK-V and NK-M. Acetylcholine and carbachol failed to reverse the blockade, indicating irreversible/pseudo-irreversible post-synaptic neuromuscular blockade. KCl restored the twitches variably (NK-M preparation being the least responsive), consistent with different degree of muscle damage. The findings support that NK-T venom has the most abundant curarimimetic alpha-neurotoxins, while NK-M venom contains more tissue-damaging cytotoxins. Pre-incubation of tissue with N. kaouthia monovalent antivenom (NKMAV) prevented venom-induced twitch depression, with the NK-T preparation needing the largest antivenom dose. NKMAV added after the onset of neuromuscular depression could only halt the inhibitory progression but failed to restore full contraction. The findings highlight the urgency of early antivenom administration to sequester as much circulating neurotoxins as possible, thereby hastening toxin elimination from the circulation. In envenomed mice, NKMAV administered upon the first neurological sign neutralized the neurotoxic effect, with the slowest full recovery noticed in the NK-T group. This is consistent with the high abundance of neurotoxins in the NK-T venom, implying that a larger amount or repeated dosing of NKMAV may be required in NK-T envenomation. PMID:26972756

  11. Effects of neutral sulfate berberine on LPS-induced cardiomyocyte TNF-αsecretion, abnormal calcium cycling, and cardiac dysfunction in rats

    Institute of Scientific and Technical Information of China (English)

    Jing YANG; Hua-dong WANG; Da-xiang LU; Yan-ping WANG; Ren-bin QI; Jing LI; Fei LI; Chu-jie LI

    2006-01-01

    Aim: To evaluate the effect of neutral sulfate berberine on cardiac function, tumornecrosis factor α (TNF-α) release, and intracellular calcium concentration ([Ca2+]i)in cardiomyocytes exposed to lipopolysaccharide (LPS). Methods: Primary cultured rat cardiomyocytes were prepared from ventricles of 3-4-day old SpragueDawley rats. TNF-α concentrations in cell-conditioned media were measured by using a Quantikine enzyme-linked immunosorbent assay kit, and cardiomyocyte [Ca2+]i was measured by using Fura-2/AM. The isolated rat hearts were perfused in the Langendorff mode. Results: LPS at doses of 1, 5, 10, and 20 μg/mL markedly stimulated TNF-α secretion from cardiomyocytes, and neutral sulfate berberine inhibited LPS-induced TNF-α production. Intracellular calcium concentration was significantly decreased after LPS stimulation for 1 h, and increased 2 h after LPS treatment. Pretreatment with neutral sulfate berberine reversed the LPS-induced [Ca2+]i alterations, although neutral sulfate berberine did not inhibit a rapid increase in cardiomyocyte [Ca2+]i induced by LPS. Perfusion of isolated hearts with LPS (100 μg/mL) for 20 min resulted in significantly impaired cardiac performance at 120 min after LPS challenge: the maximal rate of left ventricular pressure rise and fall (±dp/dtmax) decreased compared with the control. In contrast, ±dp/dtmax at 120min in hearts perfused with neutral sulfate berberine (1 μmol/L) for 10 min followed by 20 min LPS (100 μg/mL) was greater than the corresponding value in the LPS group. Conclusion: Neutral sulfate berberine inhibits LPS-stimulated myocardial TNF-α production, impairs calcium cycling, and improves LPS-induced contractile dysfunction in intact heart.

  12. Aspects of gene regulation in the diploid and tetraploid Odontophrynus americanus (Amphibia, Anura, Leptodactylidae)

    OpenAIRE

    Cianciarullo Aurora M.; Naoum Paulo C.; Bertho Álvaro L; Kobashi Leonardo S.; Beçak Willy; Soares Maurilio J

    2000-01-01

    Erythropoietic and hemoglobin DNA transcriptional activities were analyzed in the diploid and the tetraploid Odontophrynus americanus. Flow cytometric analyses of DNA, RNA and mitochondrial contents showed increased genic activity in both diploid and tetraploid animals during erythropoiesis in vivo elicited by pretreatment phenylhydrazine. Generally, higher values were seen in immature tetraploid erythroid cells. On the 10th day of recovery from anemia, large amounts of messenger RNA were fou...

  13. Effect of confinement and starvation on stress parameters in the American lobster (Homarus americanus

    Directory of Open Access Journals (Sweden)

    Edo D'Agaro

    2014-12-01

    Full Text Available The American lobster (Homarus americanus is one of the most important crustacean resources in North America. In Italy and Europe, this fishery product is available throughout the year and it has a high and increasing commercial demand. American lobsters are traditionally marketed live and stocked, without feed, in temperature controlled recirculating systems for several weeks before being sold in the market places. The current Italian legislation does not fix a maximum length of time for the crustacean confinement and specific welfare requirements. In the present research, a 4-week experiment was carried out using 42 adult H. americanus reared in 4 recirculating aquaculture tanks. After one month of confinement, mean glucose, protein and total haemocyte count levels in the hemolymph of H. americanus were stable and similar (P>0.05 to the values observed at the beginning of the experiment. Results of the proximate analysis of the abdominal muscles of H. americanus showed no significant differences in concentrations of crude protein, lipid and ash during the trial. At the end of the experiment, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analysis revealed a marked degradation of the muscle myofibrillar proteins. A number of fragments, possibly from myosin, were evident in the range between 50 and 220 kDa between time t0 and t28. Results of this study show that the main hemolymphatic variables and degradation analysis of the muscle myofibrillar proteins can be used as sensitive indicators of the crustacean stress response to confinement and starvation.

  14. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus.

    Science.gov (United States)

    Rey-Burusco, M Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R; Roe, Andrew J; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W; Córsico, Betina; Smith, Brian O

    2015-11-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein-ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male. PMID:26318523

  15. Sequence data mining in search of hookworm (Necator americanus) microRNAs.

    Science.gov (United States)

    Kulkarni, Abhijeet P; Mittal, Smriti P K

    2016-09-30

    The new world hookworm, Necator americanus is a soil-transmitted nematode responsible for Necatoriasis (a type of helminthiasis) in hosts such as humans, dogs, and cats. N. americanus genome and transcriptome has been sequenced and a draft assembly analysis has been published highlighting protein coding genes and possible drug target proteins. Hookworm microRNA identification, annotations and their public release is yet to be attempted. The same is evident from lack of hookworm miRNA information in related popular public nucleotide sequence repositories such as miRBase, GenBank, WormBase etc. Therefore, in the present study we addressed these issues using EST and assembled transcript sequence information of hookworm. Using computational approaches, we identified three miRNAs precursor sequences and their mature forms. We also identified their potential targets from hookworm ESTs and transcripts, and from human transcriptome. Overall, the results indicate presence of nematode specific miRNA homologs in N. americanus and shades light on their putative targets in worm itself and the human host. PMID:27259664

  16. Aspects of gene regulation in the diploid and tetraploid Odontophrynus americanus (Amphibia, Anura, Leptodactylidae

    Directory of Open Access Journals (Sweden)

    Cianciarullo Aurora M.

    2000-01-01

    Full Text Available Erythropoietic and hemoglobin DNA transcriptional activities were analyzed in the diploid and the tetraploid Odontophrynus americanus. Flow cytometric analyses of DNA, RNA and mitochondrial contents showed increased genic activity in both diploid and tetraploid animals during erythropoiesis in vivo elicited by pretreatment phenylhydrazine. Generally, higher values were seen in immature tetraploid erythroid cells. On the 10th day of recovery from anemia, large amounts of messenger RNA were found in both specimens. Based on the mitochondrial content, the tetraploid cells had more intense energy metabolism than the diploid cells. Diploid O. americanus had about three times more erythroid cells than tetraploid specimens, indicating that there were differences in the regulatory mechanisms of erythroid cells. Hematological parameters showed that tetraploid cells had 30% more hemoglobin than the diploid, suggesting a regulatory mechanism of hemoglobin synthesis at the transcriptional level. Cytoplasmic inclusions resembling Heinz bodies were found in both types of cells. In the tetraploid cells they were previously found associated with RNA or RNP, suggesting that other regulatory system which controls the accumulation of nontranslated RNA transcribed in excess must be present. These differences at the physiological and molecular levels during erythropoiesis reinforce the hypothesis that speciation is occurring between diploid and tetraploid O. americanus.

  17. 125I-induced DNA double strand breaks: use in calibration of the neutral filter elution technique and comparison with X-ray induced breaks

    International Nuclear Information System (INIS)

    The neutral filter elution assay, for measurement of DNA double strand breakage, has been calibrated using mouse L cells and Chinese hamster V79 cells labelled with [125I]dUrd and then held at liquid nitrogen temperature to accumulate decays. The basis of the calibration is the observation that each 125I decay, occurring in DNA, produces a DNA double strand break. Linear relationships between 125I decays per cell and lethal lesions per cell (minus natural logarithm survival) and the level of elution, were found. Using the calibration data, it was calculated that the yield of DNA double strand breaks after X-irradiation of both cell types was from 6 to 9 x 10-12 DNA double strand breaks per Gy per dalton of DNA, for doses greater than 6 Gy. Neutral filter elution and survival data for X-irradiated and 125I-labelled cells suggested that the relationships between lethal lesions and DNA double strand breakage were significantly different for both cell types. An attempt was made to study the repair kinetics for 125I-induced DNA double strand breaks, but was frustrated by the rapid DNA degradation which occurs in cells that have been killed by the freezing-thawing process. (author)

  18. A Novel Replication-Competent Vaccinia Vector MVTT Is Superior to MVA for Inducing High Levels of Neutralizing Antibody via Mucosal Vaccination

    OpenAIRE

    Huang, Xiaoxing; Lu, Bin; Yu, Wenbo; Fang, Qing; Liu, Li; Zhuang, Ke; Shen, Tingting; Wang, Haibo; Tian, Po; Zhang, Linqi; Chen, Zhiwei

    2009-01-01

    Mucosal vaccination offers great advantage for inducing protective immune response to prevent viral transmission and dissemination. Here, we report our findings of a head-to-head comparison of two viral vectors modified vaccinia Ankara (MVA) and a novel replication-competent modified vaccinia Tian Tan (MVTT) for inducing neutralizing antibodies (Nabs) via intramuscular and mucosal vaccinations in mice. MVTT is an attenuated variant of the wild-type VTT, which was historically used as a smallp...

  19. A novel replication-competent vaccinia vector MVTT is superior to MVA for inducing high levels of neutralizing antibody via mucosal vaccination

    OpenAIRE

    Xiaoxing Huang; Bin Lu; Wenbo Yu; Qing Fang; Li Liu; Ke Zhuang; Tingting Shen; Haibo Wang; Po Tian; Linqi Zhang; Zhiwei Chen

    2009-01-01

    Mucosal vaccination offers great advantage for inducing protective immune response to prevent viral transmission and dissemination. Here, we report our findings of a head-to-head comparison of two viral vectors modified vaccinia Ankara (MVA) and a novel replication-competent modified vaccinia Tian Tan (MVTT) for inducing neutralizing antibodies (Nabs) via intramuscular and mucosal vaccinations in mice. MVTT is an attenuated variant of the wild-type VTT, which was historically used as a smallp...

  20. Neutralization, by a monospecific Bothrops lanceolatus antivenom, of toxic activities induced by homologous and heterologous Bothírops snake venoms.

    Science.gov (United States)

    Bogarín, G; Romero, M; Rojas, G; Lutsch, C; Casadamont, M; Lang, J; Otero, R; Gutiérrez, J M

    1999-03-01

    A monospecific Bothrops lanceolatus antivenom, currently used in Martinique, was tested for its efficacy in the neutralization of several toxic and enzymatic activities of the venoms of B. lanceolatus, B. atrox and B. asper. When tested by the i.p. route in mice, B. lanceolatus venom had an LD50 of 12.8 microg/g. In addition, it induced local tissue damage (hemorrhage, edema and myotoxicity) and showed indirect hemolytic activity, but was devoid of coagulant effect on human plasma in vitro and of defibrinating activity in mice. Antivenom was fully effective in the neutralization of lethal, hemorrhagic, edema-forming, myotoxic and indirect hemolytic effects of B. lanceolatus venom in assays involving preincubation of venom and antivenom. When tested against the venoms of B. asper and B. atrox, the antivenom completely neutralized the lethal, hemorrhagic, myotoxic and indirect hemolytic effects, and was partially effective in neutralizing edema-forming activity. In contrast, the antivenom was ineffective in the neutralization of in vitro coagulant and in vivo defibrinating effects induced by these two venoms. PMID:10080358

  1. The nest site lottery: how selectively neutral density dependent growth suppression induces frequency dependent selection.

    Science.gov (United States)

    Argasinski, K; Broom, M

    2013-12-01

    Modern developments in population dynamics emphasize the role of the turnover of individuals. In the new approaches stable population size is a dynamic equilibrium between different mortality and fecundity factors instead of an arbitrary fixed carrying capacity. The latest replicator dynamics models assume that regulation of the population size acts through feedback driven by density dependent juvenile mortality. Here, we consider a simplified model to extract the properties of this approach. We show that at the stable population size, the structure of the frequency dependent evolutionary game emerges. Turnover of individuals induces a lottery mechanism where for each nest site released by a dead adult individual a single newborn is drawn from the pool of newborn candidates. This frequency dependent selection leads towards the strategy maximizing the number of newborns per adult death. However, multiple strategies can maximize this value. Among them, the strategy with the greatest mortality (which implies the greatest instantaneous growth rate) is selected. This result is important for the discussion about universal fitness measures and which parameters are maximized by natural selection. This is related to the fitness measures R0 and r, because the number of newborns per single dead individual equals the lifetime production of newborn R0 in models without aging. We thus have a two-stage procedure, instead of a single fitness measure, which is a combination of R0 and r. According to the nest site lottery mechanism, at stable population size, selection favors strategies with the greatest r, i.e. those with the highest turnover, from those with the greatest R0. PMID:24071631

  2. Effect of axial magnetic field variations on asymmetry-induced transport in a non-neutral plasma trap

    International Nuclear Information System (INIS)

    It has been suggested that magnetically trapped particles play a role in the asymmetry-induced radial transport observed in the Occidental non-neutral plasma trap. This magnetic trapping would occur due to a small increase (β≡δB/B≅0.4%) in magnetic field at the center of our solenoid and would keep low velocity particles confined to the ends of the trap. To test this suggestion, three coils of additional windings have been added to the trap solenoid thus allowing adjustment of the axial field variation δB. The effect of these adjustments on typical radial flux resonances is investigated. Making B as uniform as possible reduces β by a factor of 5.9, but this produces little change in the transport. Varying β over the broader range from -8.5% to 9.5% gives variations of 20%-90% in the magnitude, peak frequency, and width of the flux resonances, but these variations do not match the predictions of a simple model of trapped particle transport based on isotropic particle distributions

  3. Procalcitonin neutralizes bacterial LPS and reduces LPS-induced cytokine release in human peripheral blood mononuclear cells

    Directory of Open Access Journals (Sweden)

    Matera Giovanni

    2012-05-01

    Full Text Available Abstract Background Procalcitonin (PCT is a polypeptide with several cationic aminoacids in its chemical structure and it is a well known marker of sepsis. It is now emerging that PCT might exhibit some anti-inflammatory effects. The present study, based on the evaluation of the in vitro interaction between PCT and bacterial lipopolisaccharide (LPS, reports new data supporting the interesting and potentially useful anti-inflammatory activity of PCT. Results PCT significantly decreased (p Salmonella typhimurium (rough chemotype and Escherichia coli (smooth chemotype. Subsequently, the in vitro effects of PCT on LPS-induced cytokine release were studied in human peripheral blood mononuclear cells (PBMC. When LPS was pre-incubated for 30 minutes with different concentrations of PCT, the release of interleukin-10 (IL-10 and tumor necrosis factor alpha (TNFα by PBMC decreased in a concentration-dependent manner after 24 hours for IL-10 and 4 hours for TNFα. The release of monocyte chemotactic protein-1 (MCP-1 exhibited a drastic reduction at 4 hours for all the PCT concentrations assessed, whereas such decrease was concentration-dependent after 24 hours. Conclusions This study provides the first evidence of the capability of PCT to directly neutralize bacterial LPS, thus leading to a reduction of its major inflammatory mediators.

  4. Neutralizing S1P inhibits intratumoral hypoxia, induces vascular remodelling and sensitizes to chemotherapy in prostate cancer.

    Science.gov (United States)

    Ader, Isabelle; Gstalder, Cécile; Bouquerel, Pierre; Golzio, Muriel; Andrieu, Guillaume; Zalvidea, Santiago; Richard, Sylvain; Sabbadini, Roger A; Malavaud, Bernard; Cuvillier, Olivier

    2015-05-30

    Hypoxia promotes neovascularization, increased tumor growth, and therapeutic resistance. The transcription factor, hypoxia-inducible factor 1α (HIF-1α), has been reported as the master driver of adaptation to hypoxia. We previously identified the sphingosine kinase 1/sphingosine 1-phosphate (SphK1/S1P) pathway as a new modulator of HIF-1α under hypoxia. Taking advantage of a monoclonal antibody neutralizing extracellular S1P (sphingomab), we report that inhibition of S1P extracellular signaling blocks HIF-1α accumulation and activity in several cancer cell models exposed to hypoxia. In an orthotopic xenograft model of prostate cancer, we show that sphingomab reduces hypoxia and modifies vessel architecture within 5 days of treatment, leading to increased intratumoral blood perfusion. Supporting the notion that a transient vascular normalization of tumor vessels is the mechanism by which sphingomab exerts its effects, we demonstrate that administration of the antibody for 5 days before chemotherapy is more effective at local tumor control and metastatic dissemination than any other treatment scheduling. These findings validate sphingomab as a potential new normalization agent that could contribute to successful sensitization of hypoxic tumors to chemotherapy. PMID:25915662

  5. Mimotopes selected with a neutralizing antibody against urease B from Helicobacter pylori induce enzyme inhibitory antibodies in mice upon vaccination

    Directory of Open Access Journals (Sweden)

    Long Min

    2010-11-01

    Full Text Available Abstract Background Urease B is an important virulence factor that is required for Helicobacter pylori to colonise the gastric mucosa. Mouse monoclonal antibodies (mAbs that inhibit urease B enzymatic activity will be useful as vaccines for the prevention and treatment of H. pylori infection. Here, we produced murine mAbs against urease B that neutralize the enzyme's activity. We mapped their epitopes by phage display libraries and investigated the immunogenicity of the selected mimotopes in vivo. Results The urease B gene was obtained (GenBank accession No. DQ141576 and the recombinant pGEX-4T-1/UreaseB protein was expressed in Escherichia coli as a 92-kDa recombinant fusion protein with glutathione-S-transferase (GST. Five mAbs U001-U005 were produced by a hybridoma-based technique with urease B-GST as an immunogen. Only U001 could inhibit urease B enzymatic activity. Immunoscreening via phage display libraries revealed two different mimotopes of urease B protein; EXXXHDM from ph.D.12-library and EXXXHSM from ph.D.C7C that matched the urease B proteins at 347-353 aa. The antiserum induced by selected phage clones clearly recognised the urease B protein and inhibited its enzymatic activity, which indicated that the phagotope-induced immune responses were antigen specific. Conclusions The present work demonstrated that phage-displayed mimotopes were accessible to the mouse immune system and triggered a humoral response. The urease B mimotope could provide a novel and promising approach for the development of a vaccine for the diagnosis and treatment of H. pylori infection.

  6. Formalin-inactivated EV71 vaccine candidate induced cross-neutralizing antibody against subgenotypes B1, B4, B5 and C4A in adult volunteers.

    Directory of Open Access Journals (Sweden)

    Ai-Hsiang Chou

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 has caused several epidemics of hand, foot and mouth diseases (HFMD in Asia. No effective EV71 vaccine is available. A randomized and open-label phase I clinical study registered with ClinicalTrials.gov #NCT01268787, aims to evaluate the safety, reactogenicity and immunogenicity of a formalin-inactivated EV71 vaccine candidate (EV71vac at 5- and 10-µg doses. In this study we report the cross-neutralizing antibody responses from each volunteer against different subgenotypes of EV71 and CVA16. METHODS: Sixty eligible healthy adults were recruited and vaccinated. Blood samples were obtained on day 0, 21 and 42 and tested against B1, B4, B5, C2, C4A, C4B and CVA16 for cross-neutralizing antibody responses. RESULTS: The immunogenicity of both 5- and 10- µg doses were found to be very similar. Approximately 45% of the participants had 4-fold increase in Nt, but there was no further increase in Nt after the second dose. EV71vac induced very strong cross-neutralizing antibody responses in >85% of volunteers without pre-existing Nt against subgenotype B1, B5 and C4A. EV71vac elicited weak cross-neutralizing antibody responses (∼20% of participants against a C4B and Coxsackie virus A16. Over 90% of vaccinated volunteers did not develop cross-neutralizing antibody responses (Nt<8 against a C2 strain. EV71vac can boost and significantly enhance the neutralizing antibody responses in volunteers who already had pre-vaccination antibodies against EV71 and/or CVA16. CONCLUSION: EV71vac is efficient in eliciting cross-neutralizing antibody responses against EV71 subgenotypes B1, B4, B5, and C4A, and provides the rationale for its evaluation in phase II clinical trials. TRIAL REGISTRATION: ClinicalTrials.gov NCT01268787.

  7. Hepatitis C virus hypervariable region 1 variants presented on hepatitis B virus capsid-like particles induce cross-neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Milena Lange

    Full Text Available 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.

  8. The neutral comet assay

    International Nuclear Information System (INIS)

    The single-cell gel electrophoresis (or comet) assay is a rapid and sensitive fluorescence microscopic method that is used for the detection of DNA damage at the individual cell level. Comet assay under neutral conditions allows the detection of DNA double-strand breaks, considered to the biologically relevant radiation-induced lesion. In this report we describe modifications of the neutral comet method and its use for studying DNA damage and its repair in irradiated human lymphocytes. (author)

  9. Mucosal Immunization Induces a Higher Level of Lasting Neutralizing Antibody Response in Mice by a Replication-Competent Smallpox Vaccine: Vaccinia Tiantan Strain

    OpenAIRE

    Bin Lu; Wenbo Yu; Xiaoxing Huang; Haibo Wang; Li Liu; Zhiwei Chen

    2011-01-01

    The possible bioterrorism threat using the variola virus, the causative agent of smallpox, has promoted us to further investigate the immunogenicity profiles of existing vaccines. Here, we study for the first time the immunogenicity profile of a replication-competent smallpox vaccine (vaccinia Tiantan, VTT strain) for inducing neutralizing antibodies (Nabs) through mucosal vaccination, which is noninvasive and has a critical implication for massive vaccination programs. Four different routes ...

  10. Primer registro de oso negro americano (Ursus americanus) para el estado de Hidalgo, México

    OpenAIRE

    Alberto Enrique Rojas-Martínez; Luis Antonio Juárez-Casillas

    2013-01-01

    Se documenta el primer registro del oso negro americano (Ursus americanus) para el estado de Hidalgo, México, mismo que representa el punto más sureño de la distribución de esta especie. El ejemplar se encontró muerto cerca del poblado El Aguaje de Cerro Prieto en un lugar conocido como La Joya, municipio de La Misión, en el norte del estado, a una altitud de 1 481 m, probablemente correspondía a un individuo errante proveniente del estado de Querétaro.

  11. TESTICULAR MORPHOHISTOLOGY OF ODONTOPHRYNUS AMERICANUS (DUMERIL & BIBRÓN, 1841) (ANURA, ODONTOPHRYNIDAE) OF ARGENTINA

    OpenAIRE

    MATÍAS ALONSO; KARINA DORFLINGER; SERGIO URQUIZA; FERNANDO CAREZZANO

    2013-01-01

    We described the morphohistological features of the testis of adult Odontophrynus americanus (Dumeril & Bibrón 1841) (n = 7) from wetlands of central Argentina. Testes were processed by routine histological techniques, sectioned at 8 microns and stained with hematoxylin–eosin. The gonads are paired, yellowish and ovoid organs, 5.25 ± 0.17 mm long x 2.15 ± 0.15 mm wide. Histologically, there is a thin tunica albuginea (4.90 ± 1.05 mμ) surrounding the testicles. Inside them, there are seminifer...

  12. Behavioural responses of Odontophrynus americanus tadpoles (Anura: Leptodactylidae to fish chemical cues

    Directory of Open Access Journals (Sweden)

    Scarabotti, Pablo A.

    2007-02-01

    Full Text Available Las larvas de muchas especies de anfibios viven en ambientes con vegetación y de aguas turbias, donde la visibilidad es muy limitada. En estos ambientes, la utilización de señales químicas para la detección de depredadores podría ser más confiable que la utilización de señales visuales. Las larvas de Odontophrynus americanus habitan en las lagunas del valle aluvial del río Paraná Medio, Argentina, donde normalmente se dan condiciones de baja visibilidad. La hipótesis de este trabajo fue que los renacuajos de esta especie pueden detectar a los depredadores y responder subsecuentemente con conducta antipredador ante la percepción de señales químicas de los depredadores. En el presente trabajo se llevaron a cabo tres experimentos de laboratorio para evaluar si los renacuajos de O. americanus responden conductualmente al estímulo químico del pez Astyanax fasciatus. Las respuestas conductuales fueron evaluadas observando cambios en actividad, utilización de refugio y distribución espacial de los renacuajos. En presencia del estímulo químico del pez, los renacuajos redujeron su actividad en un 27%, incrementaron cinco veces la utilización de refugios, pero no exhibieron una respuesta de elusión espacial al estímulo del depredador. Las respuestas conductuales de los renacuajos de esta especie podrían reducir las probabilidades de encuentro y ataque por parte de los depredadores. Many amphibian larvae live in turbid and vegetated habitats with very limited visibility. In these habitats, the use of chemical cues for predator detection may be more reliable than visual ones. Odontophrynus americanus tadpoles inhabit floodplain ponds of the middle Paraná River, Argentina, where they frequently encounter low visibility conditions. We hypothesize that tadpoles of this species can detect predators and subsequently respond with antipredator behaviour by means of chemical cues from predators. In the present work, we ran three separate

  13. RETENCIÓN DE ARSÉNICO EN HUMEDALES CONSTRUIDOS CON Eleocharis macrostachya Y Schoenoplectus americanus

    OpenAIRE

    María Cecilia VALLES-ARAGÓN; María Teresa ALARCÓN-HERRERA

    2014-01-01

    El arsénico puede ser removido del agua por rizofiltración usando plantas macrófitas que tienen fenotipos de acumulación de arsénico. El objetivo de este estudio fue inves - tigar el comportamiento de Eleocharis macrostachya y Schoenoplectus americanus en humedales construidos de flujo subsuperficial, así como analizar el balance de masa de retención de arsénico en el sistema. Los experimentos se realizaron en prototipos de humedales construidos. Uno plantado con E. macrostachya (HA), otro pl...

  14. Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus

    International Nuclear Information System (INIS)

    The two recombinant apo subunits H1 and H2 from H. americanus have been structurally characterized. Reconstitution studies with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits. Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H1 and H2 from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H1 and H2 with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype–phenotype linkage

  15. A novel isothermal microcalorimetry tool to assess drug effects on Ancylostoma ceylanicum and Necator americanus.

    Science.gov (United States)

    Flores, Dayana; Panic, Gordana; Braissant, Olivier; Keiser, Jennifer

    2016-01-01

    Soil-transmitted helminths, which affect the poorest communities, worldwide cause a range of symptoms and morbidity, yet few treatment options are available and drug resistance is a concern. To improve and accelerate anthelminthic drug discovery, novel drug screening tools such as isothermal microcalorimetry (IMC) have been tested with great potential. In this study, we used a novel microcalorimeter, the calScreener™, to study the viability on the hookworms Necator americanus and Ancylostoma ceylanicum as well as the whipworm Trichuris muris. Significant heat flow signals could be obtained with already one adult worm per channel for all three species. High-amplitude oscillations were observed for the hookworms; however, adult T. muris showed a twofold heat flow decrease during the first 24 h. Antinematodal effects of ivermectin and levamisole at 1, 10, and 100 μg/ml were evaluated on adult N. americanus and A. ceylanicum. Levamisole-treated hookworms showed a decline in heat flow and oscillation amplitude in a dose-response manner. Heat flow for ivermectin-treated hookworms increased proportionally with increased concentrations of ivermectin, though the wavelet analysis showed an opposite trend as observed by flatter wavelets. In conclusion, the calScreener™ is an excellent tool to study drug effects on intestinal hookworms at the adult worm stage as it offers a lower detection limit than other IMC devices and the possibility to monitor worm viability online. PMID:26519051

  16. Experimental results on one-pion neutral current reaction in all channels induced by antineutrinos at CERN PS

    Science.gov (United States)

    Erriques, O.; Fogli-Muciaccia, M. T.; Natali, S.; Nuzzo, S.; Halsteinslid, A.; Myklebost, K.; Rognebakke, A.; Bonetti, S.; Cavalli, D.; Pullia, A.; Rollier, M.; Engel, J. P.; Guyonnet, J. L.; Huss, D.; Paty, M.; Riester, J. L.; Gamba, D.; Marzari-Chiesa, A.; Riccati, L.; Romero, A.; Bullock, F. W.; Henderson, R. C. W.; Jones, T. W.

    1980-12-01

    Single pion production, in antineutrino-nucleon interactions via the neutral current, has been studied in the bubble chamber Gargamelle, filled with propane. Complete analysis of the secondaries, including π0,s, has allowed a detailed study of all channels. After background and nuclear corrections, results are obtained which can be interpreted in terms of isospin structure of the neutral weak current and of the Salam-Weinberg angle. Agreement is found with the currently accepted value of sin 2θW and the data suggest an important contribution of I = {3}/{2} final states.

  17. Experimental results on one-pion neutral current reaction in all channels induced by antineutrinos at CERN PS

    CERN Document Server

    Erriquez, O; Bullock, F W; Cavalli, D; Engel, J P; Fogli-Muciaccia, M T; Gamba, D; Guyonnet, J L; Halsteinslid, A; Henderson, R C W; Huss, D; Jones, T W; Marzari-Chiesa, A; Myklebost, K; Natali, S; Nuzzo, S; Paty, M; Pullia, A; Riccati, L; Riester, J L; Rognebakke, A; Rollier, M; Romero, A

    1980-01-01

    Single pion production, in antineutrino-nucleon interactions via the neutral current, has been studied in the bubble chamber Gargamelle, filled with propane. Complete analysis of the secondaries, including pi /sup 0/'s, has allowed a detailed study of all channels. After background and nuclear corrections, results are obtained which can be interpreted in terms of isospin structure of the neutral weak current and of the Salam-Weinberg angle. Agreement is found with the currently accepted value of sin/sup 2/ theta /sub w/ and the data suggest an important contribution of I=/sup 3///sub 2/ final states. (11 refs).

  18. Crimean-Congo Hemorrhagic Fever Virus Subunit Vaccines Induce High Levels of Neutralizing Antibodies But No Protection in STAT1 Knockout Mice.

    Science.gov (United States)

    Kortekaas, Jeroen; Vloet, Rianka P M; McAuley, Alexander J; Shen, Xiaoli; Bosch, Berend Jan; de Vries, Laura; Moormann, Rob J M; Bente, Dennis A

    2015-12-01

    Crimean-Congo hemorrhagic fever virus is a tick-borne bunyavirus of the Nairovirus genus that causes hemorrhagic fever in humans with high case fatality. Here, we report the development of subunit vaccines and their efficacy in signal transducer and activator of transcription 1 (STAT1) knockout mice. Ectodomains of the structural glycoproteins Gn and Gc were produced using a Drosophila insect cell-based expression system. A single vaccination of STAT129 mice with adjuvanted Gn or Gc ectodomains induced neutralizing antibody responses, which were boosted by a second vaccination. Despite these antibody responses, mice were not protected from a CCHFV challenge infection. These results suggest that neutralizing antibodies against CCHFV do not correlate with protection of STAT1 knockout mice. PMID:26684523

  19. Isolation and characterization of new genetic types of toxoplasma gondii and prevalence of trichinella murrelli from black bear (Ursus americanus)

    Science.gov (United States)

    Black bears (Ursus americanus) are hosts for two important zoonotic parasites, Toxoplasma gondii and Trichinella spp. and bears are hunted for human consumption in the USA. Little is known of the genetic diversity of T. gondii circulating in wildlife. In the present study, antibodies to T. gondii we...

  20. A novel replication-competent vaccinia vector MVTT is superior to MVA for inducing high levels of neutralizing antibody via mucosal vaccination.

    Directory of Open Access Journals (Sweden)

    Xiaoxing Huang

    Full Text Available Mucosal vaccination offers great advantage for inducing protective immune response to prevent viral transmission and dissemination. Here, we report our findings of a head-to-head comparison of two viral vectors modified vaccinia Ankara (MVA and a novel replication-competent modified vaccinia Tian Tan (MVTT for inducing neutralizing antibodies (Nabs via intramuscular and mucosal vaccinations in mice. MVTT is an attenuated variant of the wild-type VTT, which was historically used as a smallpox vaccine for millions of Chinese people. The spike glycoprotein (S of SARS-CoV was used as the test antigen after the S gene was constructed in the identical genomic location of two vectors to generate vaccine candidates MVTT-S and MVA-S. Using identical doses, MVTT-S induced lower levels ( approximately 2-3-fold of anti- SARS-CoV neutralizing antibodies (Nabs than MVA-S through intramuscular inoculation. MVTT-S, however, was capable of inducing consistently 20-to-100-fold higher levels of Nabs than MVA-S when inoculated via either intranasal or intraoral routes. These levels of MVTT-S-induced Nab responses were substantially (approximately 10-fold higher than that induced via the intramuscular route in the same experiments. Moreover, pre-exposure to the wild-type VTT via intranasal or intraoral route impaired the Nab response via the same routes of MVTT-S vaccination probably due to the pre-existing anti-VTT Nab response. The efficacy of intranasal or intraoral vaccination, however, was still 20-to-50-fold better than intramuscular inoculation despite the subcutaneous pre-exposure to wild-type VTT. Our data have implications for people who maintain low levels of anti-VTT Nabs after historical smallpox vaccination. MVTT is therefore an attractive live viral vector for mucosal vaccination.

  1. A multi-subunit Chlamydia vaccine inducing neutralizing antibodies and strong IFN-γ(+) CMI responses protects against a genital infection in minipigs

    DEFF Research Database (Denmark)

    Bøje, Sarah; Olsen, Anja Weinreich; Erneholm, Karin; Agerholm, Jørgen Steen; Jungersen, Gregers; Andersen, Peter; Follmann, Frank

    2016-01-01

    Chlamydia is the most widespread sexually transmitted bacterial disease and a prophylactic vaccine is highly needed. Ideally, this vaccine is required to induce a combined response of Th1 cell-mediated immune (CMI) response in concert with neutralizing antibodies. Using a novel Göttingen minipig......F infectivity in vitro. Both Hirep1+CTH93/CAF01 and UV-SvD/CAF01 vaccination protected pigs against a vaginal C. trachomatis SvD infection. In conclusion, the Hirep1+CTH93/CAF01 vaccine proved highly immunogenic and equally protective as UV-SvD/CAF01 showing promise for the development of a subunit vaccine...

  2. Collision induced dissociation of doubly-charged ions: Coulomb explosion vs. neutral loss in [Ca(urea)]2+ gas phase unimolecular reactivity via chemical dynamics simulations

    International Nuclear Information System (INIS)

    In this paper we report different theoretical approaches to study the gas-phase unimolecular dissociation of the doubly-charged cation [Ca(urea)]2+, in order to rationalize recent experimental findings. Quantum mechanical plus molecular mechanical (QM/MM) direct chemical dynamics simulations were used to investigate collision induced dissociation (CID) and rotational-vibrational energy transfer for Ar+ [Ca(urea)]2+ collisions. For the picosecond time-domain of the simulations, both neutral loss and Coulomb explosion reactions were found and the differences in their mechanisms elucidated. The loss of neutral urea subsequent to collision with Ar occurs via a shattering mechanism, while the formation of two singly-charged cations follows statistical (or almost statistical) dynamics. Vibrational-rotational energy transfer efficiencies obtained for trajectories that do not dissociate during the trajectory integration were used in conjunction with RRKM rate constants to approximate dissociation pathways assuming complete intramolecular vibrational energy redistribution (IVR) and statistical dynamics. This statistical limit predicts, as expected, that at long time the most stable species on the potential energy surface (PES) dominate. These results, coupled with experimental CID from which both neutral loss and Coulomb explosion products were obtained, show that the gas phase dissociation of this ion occurs by multiple mechanisms leading to different products and that reactivity on the complicated PES is dynamically complex. (authors)

  3. Neutralizing Activity of Vaccine-Induced Antibodies to Two Bacillus anthracis Toxin Components, Lethal Factor and Edema Factor▿

    OpenAIRE

    Taft, Sarah C.; Weiss, Alison A.

    2007-01-01

    Anthrax vaccine adsorbed (AVA; BioThrax), the current FDA-licensed human anthrax vaccine, contains various amounts of the three anthrax toxin components, protective antigen (PA), lethal factor (LF), and edema factor (EF). While antibody to PA is sufficient to mediate protection against anthrax in animal models, it is not known if antibodies to LF or EF contribute to protection in humans. Toxin-neutralizing activity was evaluated in sera from AVA-vaccinated volunteers, all of whom had antibody...

  4. Salt-induced stabilization of apoflavodoxin at neutral pH is mediated through cation-specific effects

    OpenAIRE

    Maldonado, Susana; Irún, María Pilar; Campos, Luis Alberto; Rubio, José Antonio; Luquita, Alejandra; Lostao, Anabel; Wang, Renjie; García-Moreno E., Bertrand; Sancho, Javier

    2002-01-01

    Electrostatic contributions to the conformational stability of apoflavodoxin were studied by measurement of the proton and salt-linked stability of this highly acidic protein with urea and temperature denaturation. Structure-based calculations of electrostatic Gibbs free energy were performed in parallel over a range of pH values and salt concentrations with an empirical continuum method. The stability of apoflavodoxin was higher near the isoelectric point (pH 4) than at neutral pH. This beha...

  5. Neutral currents

    International Nuclear Information System (INIS)

    The evidence for the existence of weak neutral current has been a very controverted topics in the early 1970's, as well as the muon did in the 1930's. The history is very rich considering the evolution of the experimental techniques in high energy particle physics. The history of the discovery and the study of weak neutral current is reviewed. Later the quest of the intermediate vector boson continues with the decision of the community to build a large proton antiproton collider. (K.A.). 14 refs., 1 fig

  6. Immunization routes in cattle impact the levels and neutralizing capacity of antibodies induced against S. aureus immune evasion proteins.

    Science.gov (United States)

    Boerhout, Eveline; Vrieling, Manouk; Benedictus, Lindert; Daemen, Ineke; Ravesloot, Lars; Rutten, Victor; Nuijten, Piet; van Strijp, Jos; Koets, Ad; Eisenberg, Susanne

    2015-01-01

    Vaccines against S. aureus bovine mastitis are scarce and show limited protection only. All currently available vaccines are applied via the parenteral (usually intramuscular) route. It is unknown, however, whether this route is the most suitable to specifically increase intramammary immunity to combat S. aureus at the site of infection. Hence, in the present study, immunization via mucosal (intranasal; IN), intramuscular (triangle of the neck; IM), intramammary (IMM) and subcutaneous (suspensory ligament; SC) routes were analyzed for their effects on the quantity of the antibody responses in serum and milk as well as the neutralizing capacity of the antibodies within serum. The experimental vaccine comprised the recombinant S. aureus immune evasion proteins extracellular fibrinogen-binding protein (Efb) and the leukotoxin subunit LukM in an oil-in-water adjuvant combined with a hydrogel and alginate. The highest titer increases for both Efb and LukM specific IgG1 and IgG2 antibody levels in serum and milk were observed following SC/SC immunizations. Furthermore, the harmful effects of Efb and leukotoxin LukMF' on host-defense were neutralized by serum antibodies in a route-dependent manner. SC/SC immunization resulted in a significant increase in the neutralizing capacity of serum antibodies towards Efb and LukMF', shown by increased phagocytosis of S. aureus and increased viability of bovine leukocytes. Therefore, a SC immunization route should be considered when aiming to optimize humoral immunity against S. aureus mastitis in cattle. PMID:26411347

  7. A highly conserved epitope-vaccine candidate against varicella-zoster virus induces neutralizing antibodies in mice.

    Science.gov (United States)

    Zhu, Rui; Liu, Jian; Chen, Chunye; Ye, Xiangzhong; Xu, Longfa; Wang, Wei; Zhao, Qinjian; Zhu, Hua; Cheng, Tong; Xia, Ningshao

    2016-03-18

    Varicella-zoster virus (VZV) is a highly infectious agent of varicella and herpes zoster (HZ). Vaccination is by far the most effective way to prevent these diseases. More safe, stable and efficient vaccines, such as epitope-based vaccines, now have been increasingly investigated by many researchers. However, only a few VZV neutralizing epitopes have been identified to date. We have previously identified a linear epitope between amino acid residues 121 and 135 of gE. In this study, we validated that this epitope is highly conserved amongst different VZV strains that covered five existing phylogenetic clades with an identity of 100%. We evaluated the immunogenicity of the recombinant hepatitis B virus core (HBc) virus-like particles (VLPs) which included amino acids (121-135). VZV-gE-specific antibodies were detected in immunized mouse serum using ELISA. The anti-peptide antiserum positively detected VZV via Western blot and immunofluorescent staining assays. More importantly, these peptides could neutralize VZV, indicating that these peptides represented neutralizing epitopes. These findings have important implications for the development of epitope-based protective VZV vaccines. PMID:26873057

  8. Energetics of winter flounder (Pseudopleuronectes americanus) fed the polychaete, Nereis virens, under experimental conditions

    International Nuclear Information System (INIS)

    Age class I and II winter flounder, Pseudopleuronectes americanus, were fed the polychaete, Nereis virens, under experimental temperatures of 100C and 200C in a filtered (10 μ), temperature-regulated seawater system for periods of 40 days. All the fish grew and there was no significant difference in growth between fish at 100C and those at 200C, but growth was significantly different (P less than 0.05) between age classes at both temperatures. Age I fish had the higher growth efficiency and mean gross growth efficiencies based on calories were 23.7 percent and 20.2 percent for age I and II, respectively. Calculated efficiencies were lowest based on wet weight and generally increased when based on dry weight, carbon, and caloric content

  9. Structure of a two-CAP-domain protein from the human hookworm parasite Necator americanus

    International Nuclear Information System (INIS)

    The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite N. americanus refined to a resolution limit of 2.2 Å is presented. Major proteins secreted by the infective larval stage hookworms upon host entry include Ancylostoma secreted proteins (ASPs), which are characterized by one or two CAP (cysteine-rich secretory protein/antigen 5/pathogenesis related-1) domains. The CAP domain has been reported in diverse phylogenetically unrelated proteins, but has no confirmed function. The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite Necator americanus was refined to a resolution limit of 2.2 Å. The structure was solved by molecular replacement (MR) using Na-ASP-2, a one-CAP-domain ASP, as the search model. The correct MR solution could only be obtained by truncating the polyalanine model of Na-ASP-2 and removing several loops. The structure reveals two CAP domains linked by an extended loop. Overall, the carboxyl-terminal CAP domain is more similar to Na-ASP-2 than to the amino-terminal CAP domain. A large central cavity extends from the amino-terminal CAP domain to the carboxyl-terminal CAP domain, encompassing the putative CAP-binding cavity. The putative CAP-binding cavity is a characteristic cavity in the carboxyl-terminal CAP domain that contains a His and Glu pair. These residues are conserved in all single-CAP-domain proteins, but are absent in the amino-terminal CAP domain. The conserved His residues are oriented such that they appear to be capable of directly coordinating a zinc ion as observed for CAP proteins from reptile venoms. This first structure of a two-CAP-domain ASP can serve as a template for homology modeling of other two-CAP-domain proteins

  10. Structure of a two-CAP-domain protein from the human hookworm parasite Necator americanus

    Energy Technology Data Exchange (ETDEWEB)

    Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [Pathology and Microbiology Department, 986495 Nebraska Medical Center, Omaha, NE 68198-6495 (United States)

    2011-05-01

    The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite N. americanus refined to a resolution limit of 2.2 Å is presented. Major proteins secreted by the infective larval stage hookworms upon host entry include Ancylostoma secreted proteins (ASPs), which are characterized by one or two CAP (cysteine-rich secretory protein/antigen 5/pathogenesis related-1) domains. The CAP domain has been reported in diverse phylogenetically unrelated proteins, but has no confirmed function. The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite Necator americanus was refined to a resolution limit of 2.2 Å. The structure was solved by molecular replacement (MR) using Na-ASP-2, a one-CAP-domain ASP, as the search model. The correct MR solution could only be obtained by truncating the polyalanine model of Na-ASP-2 and removing several loops. The structure reveals two CAP domains linked by an extended loop. Overall, the carboxyl-terminal CAP domain is more similar to Na-ASP-2 than to the amino-terminal CAP domain. A large central cavity extends from the amino-terminal CAP domain to the carboxyl-terminal CAP domain, encompassing the putative CAP-binding cavity. The putative CAP-binding cavity is a characteristic cavity in the carboxyl-terminal CAP domain that contains a His and Glu pair. These residues are conserved in all single-CAP-domain proteins, but are absent in the amino-terminal CAP domain. The conserved His residues are oriented such that they appear to be capable of directly coordinating a zinc ion as observed for CAP proteins from reptile venoms. This first structure of a two-CAP-domain ASP can serve as a template for homology modeling of other two-CAP-domain proteins.

  11. Hookworm infection and anemia in adult women in rural Chiapas, Mexico Anemia e infección por Necator americanus en mujeres en Chiapas, México

    OpenAIRE

    Brentlinger, Paula E; Linnea Capps; Melinda Denson

    2003-01-01

    OBJECTIVE: To describe associations between anemia and hookworm (Necator americanus) infection in hospitalized women in rural Chiapas, Mexico. MATERIAL AND METHODS: We retrospectively reviewed the hospital records of 68 anemic women (defined as having a hemoglobin level

  12. Elicitation of neutralizing antibodies directed against CD4-induced epitope(s using a CD4 mimetic cross-linked to a HIV-1 envelope glycoprotein.

    Directory of Open Access Journals (Sweden)

    Antu K Dey

    Full Text Available The identification of HIV-1 envelope glycoprotein (Env structures that can generate broadly neutralizing antibodies (BNAbs is pivotal to the development of a successful vaccine against HIV-1 aimed at eliciting effective humoral immune responses. To that end, the production of novel Env structure(s that might induce BNAbs by presentation of conserved epitopes, which are otherwise occluded, is critical. Here, we focus on a structure that stabilizes Env in a conformation representative of its primary (CD4 receptor-bound state, thereby exposing highly conserved "CD4 induced" (CD4i epitope(s known to be important for co-receptor binding and subsequent virus infection. A CD4-mimetic miniprotein, miniCD4 (M64U1-SH, was produced and covalently complexed to recombinant, trimeric gp140 envelope glycoprotein (gp140 using site-specific disulfide linkages. The resulting gp140-miniCD4 (gp140-S-S-M64U1 complex was recognized by CD4i antibodies and the HIV-1 co-receptor, CCR5. The gp140-miniCD4 complex elicited the highest titers of CD4i binding antibodies as well as enhanced neutralizing antibodies against Tier 1 viruses as compared to gp140 protein alone following immunization of rabbits. Neutralization against HIV-2(7312/V434M and additional serum mapping confirm the specific elicitation of antibodies directed to the CD4i epitope(s. These results demonstrate the utility of structure-based approach in improving immunogenic response against specific region, such as the CD4i epitope(s here, and its potential role in vaccine application.

  13. Post-Mating Interactions and Their Effects on Fitness of Female and Male Echinothrips americanus (Thysanoptera: Thripidae), a New Insect Pest in China

    OpenAIRE

    Xiao-Wei Li; Hong-Xue Jiang; Xiao-Chen Zhang; Anthony M Shelton; Ji-Nian Feng

    2014-01-01

    Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furt...

  14. Mucosal Immunization Induces a Higher Level of Lasting Neutralizing Antibody Response in Mice by a Replication-Competent Smallpox Vaccine: Vaccinia Tiantan Strain

    Directory of Open Access Journals (Sweden)

    Bin Lu

    2011-01-01

    Full Text Available The possible bioterrorism threat using the variola virus, the causative agent of smallpox, has promoted us to further investigate the immunogenicity profiles of existing vaccines. Here, we study for the first time the immunogenicity profile of a replication-competent smallpox vaccine (vaccinia Tiantan, VTT strain for inducing neutralizing antibodies (Nabs through mucosal vaccination, which is noninvasive and has a critical implication for massive vaccination programs. Four different routes of vaccination were tested in parallel including intramuscular (i.m., intranasal (i.n., oral (i.o., and subcutaneous (s.c. inoculations in mice. We found that one time vaccination with an optimal dose of VTT was able to induce anti-VTT Nabs via each of the four routes. Higher levels of antiviral Nabs, however, were induced via the i.n. and i.o. inoculations when compared with the i.m. and s.c. routes. Moreover, the i.n. and i.o. vaccinations also induced higher sustained levels of Nabs overtime, which conferred better protections against homologous or alternating mucosal routes of viral challenges six months post vaccination. The VTT-induced immunity via all four routes, however, was partially effective against the intramuscular viral challenge. Our data have implications for understanding the potential application of mucosal smallpox vaccination and for developing VTT-based vaccines to overcome preexisting antivaccinia immunity.

  15. Investigating the mechanism for maintaining eucalcemia despite immobility and anuria in the hibernating American black bear (Ursus americanus).

    Science.gov (United States)

    Seger, Rita L; Cross, Randal A; Rosen, Clifford J; Causey, Robert C; Gundberg, Caren M; Carpenter, Thomas O; Chen, Tai C; Halteman, William A; Holick, Michael F; Jakubas, Walter J; Keisler, Duane H; Seger, Richard M; Servello, Frederick A

    2011-12-01

    Ursine hibernation uniquely combines prolonged skeletal unloading, anuria, pregnancy, lactation, protein recycling, and lipolysis. This study presents a radiographic and biochemical picture of bone metabolism in free-ranging, female American black bears (Ursus americanus) that were active (spring bears and autumn bears) or hibernating (hibernating bears). Hibernating bears included lactating and non-lactating individuals. We measured serum calcium, albumin, inorganic phosphate, creatinine, bone specific alkaline phosphatase (BSALP), CTX, parathyroid hormone, insulin-like growth factor-I (IGF-l), leptin, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D] and sclerostin from 35 to 50 tranquilized hibernating bears and 14 to 35 tranquilized spring bears. We compared metacarpal cortical indices (MCI), measured by digital X-ray radiogrammetry, from 60 hunter-killed autumn bears and 79 tranquilized, hibernating bears. MCI was greater in autumn than winter in younger bears, but showed no seasonal difference in older bears. During hibernation eucalcemia was maintained, BSALP was suppressed, and CTX was in the range expected for anuria. During hibernation 1,25(OH)(2)D was produced despite anuria. 1,25(OH)(2)D and IGF-I were less in hibernating than spring bears. In a quarter of hibernating bears, sclerostin was elevated. Leptin was greater in hibernating than spring bears. In hibernating bears, leptin correlated positively with BSALP in non-lactating bears and with CTX in lactating bears. Taken together the biochemical and radiographic findings indicate that during hibernation, bone turnover was persistent, balanced, and suppressed; bone resorption was lower than expected for an unloaded skeleton; and there was no unloading-induced bone loss. The skeleton appears to perceive that it was loaded when it was actually unloaded during hibernation. However, at the level of sclerostin, the skeleton recognized that it was unloaded. During hibernation leptin

  16. PHOTON-INDUCED FORMATION OF MOLECULAR HYDROGEN FROM A NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON: 9,10-DIHYDROANTHRACENE

    Energy Technology Data Exchange (ETDEWEB)

    Fu Yi; Szczepanski, Jan; Polfer, Nick C., E-mail: polfer@chem.ufl.edu [Department of Chemistry and Center for Chemical Physics, University of Florida, P.O. Box 117200, Gainesville, FL 32611-7200 (United States)

    2012-01-01

    Experimental results from infrared spectroscopy and mass spectrometry provide compelling evidence that UV irradiation of the neutral polycyclic aromatic hydrocarbon (PAH) 9,10-dihydroanthracene (DHA), trapped in solid argon (12 K), results in efficient (i.e., 90% yield) conversion to anthracene and molecular hydrogen. A number of dissociation pathways involving single or double hydrogen loss are investigated computationally. Among these, two mechanisms are most credible for a one-photon dissociation process involving UV photons <5.5 eV. For the lowest-energy pathway (2.3 eV), a simultaneous lengthening of the C-H bonds of H9 and H10 gives rise to an anthracene-H{sub 2} complex. A higher-energy mechanism (3.4 eV) involves an initial lengthening of the H9 C-H bond, followed by this hydrogen 'grabbing' H10, and forming H{sub 2}. The high yield of this photolysis reaction suggests that similar reactions may take place for other neutral PAHs, with implications for the formation of molecular hydrogen in regions of low UV exposure, such as in dark clouds.

  17. H5N1 whole-virus vaccine induces neutralizing antibodies in humans which are protective in a mouse passive transfer model.

    Directory of Open Access Journals (Sweden)

    M Keith Howard

    Full Text Available BACKGROUND: Vero cell culture-derived whole-virus H5N1 vaccines have been extensively tested in clinical trials and consistently demonstrated to be safe and immunogenic; however, clinical efficacy is difficult to evaluate in the absence of wide-spread human disease. A lethal mouse model has been utilized which allows investigation of the protective efficacy of active vaccination or passive transfer of vaccine induced sera following lethal H5N1 challenge. METHODS: We used passive transfer of immune sera to investigate antibody-mediated protection elicited by a Vero cell-derived, non-adjuvanted inactivated whole-virus H5N1 vaccine. Mice were injected intravenously with H5N1 vaccine-induced rodent or human immune sera and subsequently challenged with a lethal dose of wild-type H5N1 virus. RESULTS: Passive transfer of H5N1 vaccine-induced mouse, guinea pig and human immune sera provided dose-dependent protection of recipient mice against lethal challenge with wild-type H5N1 virus. Protective dose fifty values for serum H5N1 neutralizing antibody titers were calculated to be ≤1∶11 for all immune sera, independently of source species. CONCLUSIONS: These data underpin the confidence that the Vero cell culture-derived, whole-virus H5N1 vaccine will be effective in a pandemic situation and support the use of neutralizing serum antibody titers as a correlate of protection for H5N1 vaccines.

  18. Perpendicular Orientation of Nanodomains on Versatile Substrates through Self-Neutralization Induced by Star-Shaped Block Copolymers

    Science.gov (United States)

    Kim, Mooseong; Jang, Sangshin; Lee, Kyu Seong; Moon, Hong Chul; Kwak, Jongheon; Park, Jicheol; Jeon, Gumhye; Kim, Jin Kon

    A novel self-neutralization concept is introduced by designing molecular architecture of a block copolymer. Star-shaped 18 arm poly(methyl methacrylate)-block-polystyrene copolymers ((PMMA-b-PS)18) exhibiting lamellar and PMMA cylindrical nanodomains are synthesized. When a thin film of (PMMA-b-PS)18 is spin-coated on a substrate, vertically aligned lamellar and cylindrical nanodomains are obtained without any pre- or post-treatment, although thermal annealing for a short time (less than 30 min) is required to improve the spatial array of vertically aligned nanodomains. This result is attributed to the star-shaped molecular architecture that overcomes the difference in the surface affinity between PS and PMMA chains. Moreover, vertical orientations are observed on versatile substrates, for instance, semiconductor (Si, SiOx), metal (Au), PS or PMMA-brushed substrate, and a flexible polymer sheet of polyethylene naphthalate.

  19. Infective larvae of the human hookworms Necator americanus and Ancylostoma duodenale differ in their orientation behaviour when crawling on surfaces.

    OpenAIRE

    Syafruddin D

    2004-01-01

    The infective third stage larvae of hookworms infect their hosts by active skin invasion, and they find and recognize their hosts by the behavioural phases of activation, directed crawling, and penetration. Here we analyse the orientation of the infective larvae of the human hookworms Necator americanus and Ancylostoma duodenale when crawling on surfaces. Their behaviour differed from that of the larvae of the dog hookworm Ancylostoma caninum, but the two species also differed from each other...

  20. Molecular Detection of Ancylostoma duodenale, Ancylostoma ceylanicum, and Necator americanus in Humans in Northeastern and Southern Thailand

    OpenAIRE

    Phosuk, Issarapong; Intapan, Pewpan M.; Thanchomnang, Tongjit; Sanpool, Oranuch; Janwan, Penchom; Laummaunwai, Porntip; Aamnart, Witthaya; Morakote, Nimit; Maleewong, Wanchai

    2013-01-01

    The 2 principal species of hookworms infecting humans are Necator americanus and Ancylostoma duodenale. Case studies on zoonotic hookworm infections with Ancylostoma ceylanicum and/or Ancylostoma caninum are known mainly from Asian countries. Of these 2 zoonotic species, only A. ceylanicum can develop to adulthood in humans. In the present study, we report a molecular-based survey of human hookworm infections present in southern and northeastern Thailand. Thirty larval hookworm samples were o...

  1. Investigating Methods to Reduce Black Bear (Ursus americanus) Visitation to Anthropogenic Food Sources: Conditioned Taste Aversion and Food Removal

    OpenAIRE

    Signor, Kari D.

    2009-01-01

    Conflicts between humans and black bears (Ursus americanus) jeopardize the safety of both humans and bears, especially when bears become food-conditioned to anthropogenic food sources in areas such as campgrounds. Interest in using non-lethal techniques, such as aversive conditioning, to manage such conflicts is growing. I conducted a captive experiment at The Wildlife Science Center in Minnesota and two field experiments in the La Sal Mountains, Utah, to investigate the effects of taste av...

  2. Electroweak Chiral Lagrangian for Neutral Higgs Boson

    Institute of Scientific and Technical Information of China (English)

    WANG Shun-Zhi; WANG Qing

    2008-01-01

    A neutral Higgs boson is added into the traditional electroweak chiral Lagrangian by writing down all possible high dimension operators. The matter part of the Lagrangian is investigated in detail. We find that if Higgs field dependence of Yukawa couplings can be factorized out, there will be no flavour changing neutral couplings; neutral Higgs can induce coupling between light and heavy neutrinos.

  3. Neutral atom traps.

    Energy Technology Data Exchange (ETDEWEB)

    Pack, Michael Vern

    2008-12-01

    This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

  4. Neutral multi-MeV/u particles from laser-induced processes in ultra-dense deuterium D(0): accurate two-collector timing and magnetic analysis

    CERN Document Server

    Holmlid, Leif

    2015-01-01

    Laser-induced processes in ultra-dense deuterium D(0) layers eject multi-MeV u-1 particles using ns laser pulse energies of <200 mJ. Such particles have been observed previously as mA currents to time-of-flight (TOF) collectors at up to 1 m distance. The signal current is mainly due to the ejection of secondary electrons by impinging MeV particles on the collectors. Improved two-collector time-of-flight measurements now show that the energy of the particles is in the range 1-50 MeV u-1. Their distributions are almost thermal at up to 13 MeV u-1 or are sharper than thermal. The fastest sharp peak may indicate shock-wave acceleration by many-body energy transfer. A magnetic field of 0.4 T deflects only a small part of the multi-MeV particle flux which thus mainly consists of neutral particles. By combining the TOF method with magnetic deflection, it is ascertained that the multi-MeV particles are studied and not any slower particle emission from the target. The neutral multi-MeV particles are concluded to be...

  5. Monetary Neutrality

    OpenAIRE

    Apostolos Serletis; Zisimos Koustas

    2015-01-01

    We test the long-run neutrality of money proposition for the United States using the King and Watson (1997) methodology paying attention to the integration and cointegration properties of the variables. We use quarterly data (over the period from 1967:1 to 2014:1) and the new Center for Financial Stability Divisia monetary aggregates, documented in detail in Barnett et al. (2013). We make a comparison among the narrower monetary aggregates, M1 M2M, M2M, M2, and ALL, and the broad monetary agg...

  6. Heterologous prime-boost immunization regimens using adenovirus vector and virus-like particles induce broadly neutralizing antibodies against H5N1 avian influenza viruses.

    Science.gov (United States)

    Lin, Shih-Chang; Liu, Wen-Chun; Lin, Yu-Fen; Huang, Yu-Hsuan; Liu, Jin-Hwang; Wu, Suh-Chin

    2013-11-01

    Highly pathogenic avian influenza (HPAI) H5N1 viruses continue to trigger severe diseases in poultry and humans, prompting efforts to develop an effective vaccine. Toward that goal, we constructed a recombinant adenovirus vector encoding influenza hemagglutin (rAd-HA) and a flagellin-containing virus-like particle (FliC-VLP). Using a murine model, we investigated a heterologous prime-boost vaccination regimen combining these two vectors. Our results indicate that priming with the rAd-HA vector followed by a FliC-VLP booster induced the highest HA-specific total IgG, IgG1and IgG2a. Maximum neutralizing antibody titers against homologous and heterologous clades of H5N1 virus strains and hemagglutination inhibition resulted from the heterologous vaccination strategy. Our results are likely to contribute to the development of more effective H5N1 vaccines. PMID:23813782

  7. Collision-induced dissociation of Co+n (n=2--18) with Xe: Bond energies of cationic and neutral cobalt clusters, dissociation pathways, and structures

    International Nuclear Information System (INIS)

    The kinetic energy dependence of collision-induced dissociation (CID) of Co+n (n=2--18) with xenon is studied by using a guided ion beam mass spectrometer. Examination of the general dissociation behavior over a broad collision energy range shows that cobalt cluster cations dissociate exclusively by loss of single atoms (cluster ''evaporation''), with no evidence found for elimination of molecular cluster fragments. Bond dissociation energies for cobalt cluster cations, Co+n (n=2--18), are determined from measurements of the CID thresholds. Bond energies for neutral cobalt clusters, Con (n=4--18), are derived by combining these cationic bond energies with ionization energies for Con from the literature. The dependence of binding energy on cluster size is similar to that observed for iron clusters, and inspires some speculation regarding cluster ion structures

  8. Neutral Particle Analyzer Vertically Scanning Measurements of MHD-induced Energetic Ion Redistribution or Loss in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    S.S. Medley, R. Andre, R.E. Bell, D.S. Darrow, C.W. Domier, E.D. Fredrickson, N.N. Gorelenkov, S.M. Kaye, B.P. LeBlanc, K.C. Lee, F.M. Levinton, D. Liu, N.C. Luhmann, Jr., J.E. Menard, H. Park, D. Stutman, A.L. Roquemore, K. Tritz, H. Yuh and the NSTX Team

    2007-11-15

    Observations of magneto-hydro-dynamic (MHD) induced redistribution or loss of energetic ions measured using the vertically scanning capability of the Neutral Particle Analyzer diagnostic on the National Spherical Torus Experiment (NSTX) are presented along with TRANSP and ORBIT code analysis of the results. Although redistribution or loss of energetic ions due to bursting fishbone-like and low-frequency (f ~ 10 kHz) kinktype MHD activity has been reported previously, the primary goal of this work is to study redistribution or loss due to continuous Alfvénic (f ~ 20 – 150 kHz) modes, a topic that heretofore has not been investigated in detail for NSTX plasmas. Initial indications are that the former drive energetic ion loss whereas the continuous Alfvénic modes only cause redistribution and the energetic ions remain confined.

  9. Neutral Particle Analyzer Vertically Scanning Measurements of MHD-induced Energetic Ion Redistribution or Loss in the National Spherical Torus Experiment

    International Nuclear Information System (INIS)

    Observations of magneto-hydro-dynamic (MHD) induced redistribution or loss of energetic ions measured using the vertically scanning capability of the Neutral Particle Analyzer diagnostic on the National Spherical Torus Experiment (NSTX) are presented along with TRANSP and ORBIT code analysis of the results. Although redistribution or loss of energetic ions due to bursting fishbone-like and low-frequency (f ∼ 10 kHz) kinktype MHD activity has been reported previously, the primary goal of this work is to study redistribution or loss due to continuous Alfvenic (f ∼ 20-150 kHz) modes, a topic that heretofore has not been investigated in detail for NSTX plasmas. Initial indications are that the former drive energetic ion loss whereas the continuous Alfvenic modes only cause redistribution and the energetic ions remain confined.

  10. TRIGLYCERIDE-RICH LIPOPROTEIN LIPOLYSIS RELEASES NEUTRAL AND OXIDIZED FREE FATTY ACIDS THAT INDUCE ENDOTHELIAL CELL INFLAMMATION

    Science.gov (United States)

    Objective–Increased products of triglyceride-rich lipoprotein (TGRL) lipolysis provide a pro-inflammatory stimulus that may alter endothelial barrier function. To probe the mechanism of this lipolysis-induced dysfunction, we evaluated the pro-inflammatory potential of lipid classes derived from huma...

  11. Effects of cooking on levels of PCBs in the fillets of winter flounder (Pseudopleuronectes americanus)

    Energy Technology Data Exchange (ETDEWEB)

    Poston, T.M. [Pacific Northwest Lab., Richland, WA (United States); Durell, G.S.; Koczwara, G.; Spellacy, A.M. [Battelle Ocean Sciences, Duxbury, MA (United States)

    1995-08-01

    The Pacific Northwest Laboratory and Battelle Ocean Sciences performed a study to determine the effect of cooking on polychlorinated biphenyl (PCB) levels in the fillets of winter flounder (Pseudopleuronectes americanus). Broiling, pan frying, and deep frying in oil were tested on fillets from 21 fish collected from New Bedford Harbor, Massachusetts, on February 21, 1991. The evaluation involved estimating the change in PCB concentrations using a mass-balance approach that factored the change in fillet weight resulting from cooking with the changes in PCB concentration expressed on a precooked wet-weight basis. Deep frying in oil resulted in a 47% reduction in total PCB levels in fillet tissue. Additionally, deep frying caused a 40% reduction in fillet mass. Pan frying and broiling resulted in statistically in insignificant increases in total PCB levels of 15% and 17%, respectively. Fillet mass reductions resulting from pan frying and broiling were 7% and 15%, respectively. The effects of cooking on 18 individual congeners generally paralleled the results observed for total PCB. All 18 congeners were significantly reduced by deep frying. Congener Cl{sub 2}(08) also was significantly reduced by either pan frying. Congeners Cl{sub 5}(105) and Cl{sub 5}(118) showed apparent significant increases in concentrations following pan frying. Congeners Cl{sub 5}(105), Cl{sub 5}(118), and C1{sub 6}(138) showed significant increases in concentration following broiling.

  12. Sarcocystis oreamni, n. sp. (Apicomplexa: Sarcocystidae) from the mountain goat (Oreamnos americanus).

    Science.gov (United States)

    Calero-Bernal, Rafael; Van Wilpe, Erna; White, Kevin; Verma, Shiv K; Cerqueira-Cézar, Camila K; Dubey, Jitender P

    2015-11-01

    Numerous species of Sarcocystis have been reported from wild ruminants, but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of three of seven mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; one had Sarcocystis cornagliai-like sarcocysts, previously named from the Alpine ibex (Capra ibex) from Europe. Two other goats were infected with a new species, Sarcocystis oreamni. Sarcocystis oreamni sarcocysts were microscopic with 2 μm-thick sarcocyst wall. By transmission electron microscopy, the sarcocyst wall had 1.7 μm-thick with unusual molar tooth-like villar protrusions (vp), type 29. The vp had an electron dense core and two disc-shaped plaques at the tip with fine microtubules. Bradyzoites were 8.6-9.1 μm long. Single nucleotide polymorphism (SNP) identified in 18S rRNA, and 28S rRNA loci of rDNA regions that suggested S. oreamni molecularly apart from related species. The phylogenetic analysis based on 18S rRNA and 28S rRNA sequences suggested S. oreamni is related with Sarcocystis species that employ members of the Canidae family as their definitive host. PMID:26255900

  13. Serosurvey for selected pathogens in free-ranging American black bears (Ursus americanus) in Maryland, USA.

    Science.gov (United States)

    Bronson, Ellen; Spiker, Harry; Driscoll, Cindy P

    2014-10-01

    American black bears (Ursus americanus) in Maryland, USA, live in forested areas in close proximity to humans and their domestic pets. From 1999 to 2011, we collected 84 serum samples from 63 black bears (18 males; 45 females) in five Maryland counties and tested them for exposure to infectious, including zoonotic, pathogens. A large portion of the bears had antibody to canine distemper virus and Toxoplasma gondii, many at high titers. Prevalences of antibodies to zoonotic agents such as rabies virus and to infectious agents of carnivores including canine adenovirus and canine parvovirus were lower. Bears also had antibodies to vector-borne pathogens common to bears and humans such as West Nile virus, Borrelia burgdorferi, Rickettsia rickettsii, and Anaplasma phagocytophilum. Antibodies were detected to Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. We did not detect antibodies to Brucella canis or Ehrlichia canis. Although this population of Maryland black bears demonstrated exposure to multiple pathogens of concern for humans and domesticated animals, the low levels of clinical disease in this and other free-ranging black bear populations indicate the black bear is likely a spillover host for the majority of pathogens studied. Nevertheless, bear populations living at the human-domestic-wildlife interface with increasing human and domestic animal exposure should continue to be monitored because this population likely serves as a useful sentinel of ecosystem health. PMID:25075540

  14. Neutralization by Insulin of the Hypertensive Effect of Dermcidin Isoform 2: An Environmentally Induced Diabetogenic and Hypertensive Protein

    OpenAIRE

    Rajeshwary Ghosh; Sarbashri Bank; Rabindra Bhattacharya; Khan, Nighat N.; A. Kumar Sinha

    2014-01-01

    The effect of dermcidin isoform 2 (dermcidin), an environmentally induced stress protein, was investigated on the genesis of diabetes mellitus and hypertension, the two major atherosclerotic risk factors. The role of dermcidin as an atherosclerotic risk factor related to the impaired systemic insulin level was investigated. Dermcidin was prepared by electrophoresis using plasma from the subjects with acute ischemic heart disease. Injection of 0.2 μM dermcidin in mice increased the blood gluco...

  15. Fragmentation study of isolated and nanosolvated biomolecules induced by collision with multiply charged ions and neutral particles

    OpenAIRE

    Bernigaud, Virgile

    2009-01-01

    This thesis concerns a gas phase study of the fragmentation of biomolecular systems induced by slow collisions with multiply charged ions (in the keV-region), alkali atoms and rare gases. The main objective was to study the physical processes involved in the dissociation of highly electronically excited systems. In order to elucidate the intrinsic properties of certain biomolecules (porphyrins and amino acids) we have performed experiments in the gas phase with isolated systems. The obtained ...

  16. Cold ion-neutral reactions

    OpenAIRE

    Hall, Felix Henry Joynson

    2013-01-01

    Cold ion-neutral reactive processes were studied in an hybrid trap down to average collision energies /k_B > 20 mK. The atomic ion-neutral systems Ca^+ + Rb and Ba^+ + Rb were studied, and the results interpreted with high-level quantum chemical and quantum scattering calculations. Three reactive processes were found to be in competition, namely non-radiative charge transfer induced by non-adiabatic couplings between potential energy surfaces, radiative charge transfer, and radiative associat...

  17. Neutralization of ADAM8 ameliorates liver injury and accelerates liver repair in carbon tetrachloride-induced acute liver injury.

    Science.gov (United States)

    Li, San-Qiang; Zhu, Sha; Wan, Xue-Dong; Xu, Zheng-Shun; Ma, Zhao

    2014-04-01

    Although some studies have described the function of ADAM8 (a disintegrin and metalloprotease 8) related with rheumatoid arthritis, cancer and asthma, etc., the concrete role of ADAM8 in acute liver injury is still unknown. So mice respectively received anti-ADAM8 monoclonal antibody (mAb) of 100 μg/100 μl, 200 μg/100 μl or 300 μg/100 μl in PBS or PBS pre-injection. Then acute liver injury was induced in the mice by intraperitoneal (i.p.) injection of carbon tetrachloride (CCl₄). Serum AST and ALT level, Haematoxylin-eosin (H&E) staining, the expression level of vascular endothelial growth factor (VEGF), cytochrome P450 1A2 (CYP1A2) and proliferating cell nuclear antigen (PCNA) were detected in the mice after CCl4 administration. Our results showed that anti-ADAM8 mAb pre-injection could effectively lower AST and ALT levels (P < 0.05 or P < 0.01) and reduce liver injury (P < 0.05 or P <0.01), induce the expression of VEGF, CYP1A2 and PCNA (P <0.05 or P < 0.01) in dose-dependent manner compared with the control mice which received PBS pre-injection. In summary, our study suggested that ADAM8 might promote liver injury by inhibiting the proliferation of hepatocytes, angiogenesis and affecting the metabolism function of liver during acute liver injury induced by CCl₄. Anti-ADAM8 mAb injection might be suitable as a potential method for acute liver injury therapy. PMID:24646716

  18. Fragmentation study of isolated and nano-solvated biomolecules induced by collision with multiply charged ions and neutral particles

    International Nuclear Information System (INIS)

    This thesis concerns a gas phase study of the fragmentation of bio-molecular systems induced by slow collisions with multiply charged ions (in the keV-region), alkali atoms and rare gases. The main objective was to study the physical processes involved in the dissociation of highly electronically excited systems. In order to elucidate the intrinsic properties of certain biomolecules (porphyrins and amino acids) we have performed experiments in the gas phase with isolated systems. The obtained results demonstrate the high stability of porphyrins after electron removal and attachment. Furthermore, a dependence of the fragmentation pattern produced by multiply charged ions on the isomeric structure of the alanine molecule has been shown. In a second part of the thesis, a strong influence of the environment of the biomolecule on the fragmentation channels, their modification and their new opening, has been clearly proven. This phenomenon occurs in the presence of other surrounding biomolecules (clusters of nucleobases) as well as for molecules of a solvent (molecules of water, methanol and acetonitrile) in which the biomolecule is embedded. In order to extend these studies to larger systems, a new experimental set-up, based on an electro-spray ion source combined with a quadrupole mass filter has been developed. Due to the successful tests and proposed improvements of the device future experiments will become available concerning the fragmentation of large charged and solvated bio-molecular systems induced by collision processes. (author)

  19. Amines are likely to enhance neutral and ion-induced sulfuric acid-water nucleation in the atmosphere more effectively than ammonia

    Directory of Open Access Journals (Sweden)

    T. Kurtén

    2008-07-01

    Full Text Available We have studied the structure and formation thermodynamics of dimer clusters containing H2SO4 or HSO4 together with ammonia and seven different amines possibly present in the atmosphere, using the high-level ab initio methods RI-MP2 and RI-CC2. As expected from e.g. proton affinity data, the binding of all studied amine-H2SO4 complexes is significantly stronger than that of NH3•H2SO4, while most amine-HSO4 complexes are only somewhat more strongly bound than NH3•HSO4. Further calculations on larger cluster structures containing dimethylamine or ammonia together with two H2SO4 molecules or one H2SO4 molecule and one HSO4 ion demonstrate that amines, unlike ammonia, significantly assist the growth of not only neutral but also ionic clusters along the H2SO4 co-ordinate. A sensitivity analysis indicates that the difference in complexation free energies for amine- and ammonia-containing clusters is large enough to overcome the mass-balance effect caused by the fact that the concentration of amines in the atmosphere is probably 2 or 3 orders of magnitude lower than that of ammonia. This implies that amines might be more important than ammonia in enhancing neutral and especially ion-induced sulfuric acid-water nucleation in the atmosphere.

  20. Amines are likely to enhance neutral and ion-induced sulfuric acid-water nucleation in the atmosphere more effectively than ammonia

    Directory of Open Access Journals (Sweden)

    T. Kurtén

    2008-04-01

    Full Text Available We have studied the structure and formation thermodynamics of dimer clusters containing H2SO4 or HSO4 together with ammonia and seven different amines possibly present in the atmosphere, using the high-level ab initio methods RI-MP2 and RI-CC2. As expected from e.g. proton affinity data, the binding of all studied amine – H2SO4 complexes is significantly stronger than that of NH3•H2SO4, while most amine – HSO4 complexes are only somewhat more strongly bound than NH3•HSO4. Further calculations on larger cluster structures containing dimethylamine or ammonia together with two H2SO4 molecules or one H2SO4 molecule and one HSO4 ion demonstrate that amines, unlike ammonia, significantly assist the growth of not only neutral but also ionic clusters along the H2SO4 co-ordinate. A sensitivity analysis indicates that the difference in complexation free energies for amine- and ammonia-containing clusters is large enough to overcome the mass-balance effect caused by the fact that the concentration of amines in the atmosphere is probably 2 or 3 orders of magnitude lower than that of ammonia. This implies that amines might be more important than ammonia in enhancing neutral and especially ion-induced sulfuric acid-water nucleation in the atmosphere.

  1. Neutral currents

    International Nuclear Information System (INIS)

    A short survey of the new experimental data on weak neutral currents is given, followed by a comparison with modern theoretical models. Cross sections of the anti νsub(e)e → anti νsub(e)e, anti νsub(μ)e→ νsub(μ)e, νp → νp and anti νp → anti νp elastic scattering as well as inclusive cross sections of the ν+N → ν+X and anti ν+N → anti ν+X deep inelastic scattering are presented. On the basis of the comparison the Weinberg-Salam model is concluded to be in a good agreement with the shape of the cross sections. Six-quark vector models appear to be ruled out. The five-quark model due to Achiman, Koller and Walsh and two versions of the Gursey-Sikivie model satisfactorily account for the observed data in shape and in magnitude

  2. Laser Induced Emission Spectroscopy of Cold and Isolated Neutral PAHs and PANH: Implications for the red rectangle emission

    Science.gov (United States)

    Bejaoui, Salma; Salama, Farid; Sciamma O'Brien, Ella

    2016-06-01

    Blue luminescence (BL) in the emission spectra of the red rectangle centered on the bright star HD44179 is recently reported by Vijh et al [1]. This results is consistent with the broad band polarization measurements obtained in 1980 by Schmidt et al. Both experimental and theoretical studies support that BL emission could be attributed the luminescence of Polycyclic Aromatic Hydrocarbon (PAH) excited with ultraviolet light from the center of the star [4 and reference therein]. The abundance on N to C in the interstellar medium suggest also that nitrogen substituted PAH (PANH) are likely abundant in the interstellar medium [3]. They exhibit similar features as PAHs and could contribute to the unidentified spectral bands. Comparing the BL to laboratory spectra obtained on similar environment is crucial for the identification of interstellar molecules. We present in this works the absorption and the laser induced emission spectra of several isolated and cold PAHs and PANHs. Laser induced emission was performed first to PAHs and PANHs isolated in Argon matrix at 10 K. Then, measurements are performed with the supersonic jet technique of the COSmIC laboratory facility at NASA Ames. We focus, here, on the emission spectra (fluorescence and (or) phosphorescence) of these molecules and we discuss their contributions to the blue luminescence emission in the Red Rectangle nebula.[1] Vijh,U.P., Witt. A.N. & Gordon,K.D, APJ, 606, L69 (2004)[2] Schmidt, G. D., Cohen, M. & Margon, B., ApJ, 239L.133S (1980)[3] Spitzer, L., Physical Processes in the Interstellar Medium (New York Wiley-Interscience) (1978)[4] Salama, F., Galazutdinov, G. A., Kre lowski, J., Allamandola, L. J., & Musaev, F. A. ApJ, 526,(1999)

  3. Neutralization of TSLP inhibits airway remodeling in a murine model of allergic asthma induced by chronic exposure to house dust mite.

    Directory of Open Access Journals (Sweden)

    Zhuang-Gui Chen

    Full Text Available Chronic allergic asthma is characterized by Th2-typed inflammation, and contributes to airway remodeling and the deterioration of lung function. However, the initiating factor that links airway inflammation to remodeling is unknown. Thymic stromal lymphopoietin (TSLP, an epithelium-derived cytokine, can strongly activate lung dendritic cells (DCs through the TSLP-TSLPR and OX40L-OX40 signaling pathways to promote Th2 differentiation. To determine whether TSLP is the underlying trigger of airway remodeling in chronic allergen-induced asthma, we induced allergic airway inflammation in mice by intranasal administration of house dust mite (HDM extracts for up to 5 consecutive weeks. We showed that repeated respiratory exposure to HDM caused significant airway eosinophilic inflammation, peribronchial collagen deposition, goblet cell hyperplasia, and airway hyperreactivity (AHR to methacholine. These effects were accompanied with a salient Th2 response that was characterized by the upregulation of Th2-typed cytokines, such as IL-4 and IL-13, as well as the transcription factor GATA-3. Moreover, the levels of TSLP and transforming growth factor beta 1 (TGF-β1 were also increased in the airway. We further demonstrated, using the chronic HDM-induced asthma model, that the inhibition of Th2 responses via neutralization of TSLP with an anti-TSLP mAb reversed airway inflammation, prevented structural alterations, and decreased AHR to methacholine and TGF-β1 level. These results suggest that TSLP plays a pivotal role in the initiation and persistence of airway inflammation and remodeling in the context of chronic allergic asthma.

  4. Fatal Caprine arthritis encephalitis virus-like infection in 4 Rocky Mountain goats (Oreamnos americanus).

    Science.gov (United States)

    Patton, Kristin M; Bildfell, Robert J; Anderson, Mark L; Cebra, Christopher K; Valentine, Beth A

    2012-03-01

    Over a 3.5-year period, 4 Rocky Mountain goats (Oreamnos americanus), housed at a single facility, developed clinical disease attributed to infection by Caprine arthritis encephalitis virus (CAEV). Ages ranged from 1 to 10 years. Three of the goats, a 1-year-old female, a 2-year-old male, and a 5-year-old male, had been fed raw domestic goat milk from a single source that was later found to have CAEV on the premises. The fourth animal, a 10-year-old male, had not ingested domestic goat milk but had been housed with the other 3 Rocky Mountain goats. All 4 animals had clinical signs of pneumonia prior to death. At necropsy, findings in lungs included marked diffuse interstitial pneumonia characterized histologically by severe lymphoplasmacytic infiltrates with massive alveolar proteinosis, interstitial fibrosis, and type II pneumocyte hyperplasia. One animal also developed left-sided hemiparesis, and locally extensive lymphoplasmacytic myeloencephalitis was present in the cranial cervical spinal cord. Two animals had joint effusions, as well as severe lymphoplasmacytic and ulcerative synovitis. Immunohistochemical staining of fixed sections of lung tissue from all 4 goats, as well as spinal cord in 1 affected animal, and synovium from 2 affected animals were positive for CAEV antigen. Serology testing for anti-CAEV antibodies was positive in the 2 goats tested. The cases suggest that Rocky Mountain goats are susceptible to naturally occurring CAEV infection, that CAEV from domestic goats can be transmitted to this species through infected milk and by horizontal transmission, and that viral infection can result in clinically severe multisystemic disease. PMID:22379056

  5. Behavioral Thermoregulation and Trade-Offs in Juvenile Lobster Homarus americanus.

    Science.gov (United States)

    Nielsen, Travis V; McGaw, Iain J

    2016-02-01

    Water temperature influences the behavior and distribution patterns of both larval and adult American lobster Homarus americanus. However, very little is known about the responses of juvenile lobsters. The juvenile life stage is a critical period; high levels of mortality, combined with specific behavioral responses, can disconnect larval settlement from patterns of abundance of adults. We assessed behavioral thermoregulation in juvenile lobsters, and determined how thermal preferences can be altered by the presence of shelter and food. Juvenile lobsters avoided temperatures higher than 20 °C and lower than 8 °C, and had a mean temperature preference of 16.2 ± 1 °C. This preference was unaffected by prior acclimation, origin (laboratory-raised or wild), or size. When the animals were subjected to a temperature change (5-20 °C), activity rates peaked at 15 °C, and remained stable thereafter. Activity rates did not change when a shelter was added. The addition of food resulted in an increase in activity associated with food handling. When juvenile lobsters were offered a choice between temperature, shelter, and food, they always chose the environment with a shelter, even when it was in a thermally unfavorable temperature. Juveniles also spent more time in a thermally unfavorable environment when food was present; however, acquisition of a shelter was prioritized over food. Although juveniles had a similar thermal preference to adults, they are more vulnerable to predation; the innate shelter-seeking behavior of juveniles overrode their thermal preference. While temperature is an important environmental factor affecting the physiology, distribution, and growth of aquatic ectotherms, our findings suggest that trade-off behaviors occur in order to maintain optimal fitness and survival of the individual. PMID:26896176

  6. Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus

    Directory of Open Access Journals (Sweden)

    Yan Jun

    2011-03-01

    Full Text Available Abstract Background Hibernation is an adaptive strategy to survive in highly seasonal or unpredictable environments. The molecular and genetic basis of hibernation physiology in mammals has only recently been studied using large scale genomic approaches. We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. Results We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3, which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Conclusions Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments.

  7. Structural and functional characterization of a multifunctional alanine-rich peptide analogue from Pleuronectes americanus.

    Directory of Open Access Journals (Sweden)

    Ludovico Migliolo

    Full Text Available Recently, defense peptides that are able to act against several targets have been characterized. The present work focuses on structural and functional evaluation of the peptide analogue Pa-MAP, previously isolated as an antifreeze peptide from Pleuronectes americanus. Pa-MAP showed activities against different targets such as tumoral cells in culture (CACO-2, MCF-7 and HCT-116, bacteria (Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923, viruses (HSV-1 and HSV-2 and fungi (Candida parapsilosis ATCC 22019, Trichophyton mentagrophytes (28d&E and T. rubrum (327. This peptide did not show toxicity against mammalian cells such as erythrocytes, Vero and RAW 264.7 cells. Molecular mechanism of action was related to hydrophobic residues, since only the terminal amino group is charged at pH 7 as confirmed by potentiometric titration. In order to shed some light on its structure-function relations, in vitro and in silico assays were carried out using circular dichroism and molecular dynamics. Furthermore, Pa-MAP showed partial unfolding of the peptide changes in a wide pH (3 to 11 and temperature (25 to 95°C ranges, although it might not reach complete unfolding at 95°C, suggesting a high conformational stability. This peptide also showed a conformational transition with a partial α-helical fold in water and a full α-helical core in SDS and TFE environments. These results were corroborated by spectral data measured at 222 nm and by 50 ns dynamic simulation. In conclusion, data reported here show that Pa-MAP is a potential candidate for drug design against pathogenic microorganisms due to its structural stability and wide activity against a range of targets.

  8. Necator americanus and helminth co-infections: further down-modulation of hookworm-specific type 1 immune responses.

    Directory of Open Access Journals (Sweden)

    Stefan Michael Geiger

    2011-09-01

    Full Text Available BACKGROUND: Helminth co-infection in humans is common in tropical regions of the world where transmission of soil-transmitted helminths such as Ascaris lumbricoides, Trichuris trichiura, and the hookworms Necator americanus and Ancylostoma duodenale as well as other helminths such as Schistosoma mansoni often occur simultaneously. METHODOLOGY: We investigated whether co-infection with another helminth(s altered the human immune response to crude antigen extracts from either different stages of N. americanus infection (infective third stage or adult or different crude antigen extract preparations (adult somatic and adult excretory/secretory. Using these antigens, we compared the cellular and humoral immune responses of individuals mono-infected with hookworm (N. americanus and individuals co-infected with hookworm and other helminth infections, namely co-infection with either A. lumbricoides, Schistosoma mansoni, or both. Immunological variables were compared between hookworm infection group (mono- versus co-infected by bootstrap, and principal component analysis (PCA was used as a data reduction method. CONCLUSIONS: Contrary to several animal studies of helminth co-infection, we found that co-infected individuals had a further downmodulated Th1 cytokine response (e.g., reduced INF-γ, accompanied by a significant increase in the hookworm-specific humoral immune response (e.g. higher levels of IgE or IgG4 to crude antigen extracts compared with mono- infected individuals. Neither of these changes was associated with a reduction of hookworm infection intensity in helminth co-infected individuals. From the standpoint of hookworm vaccine development, these results are relevant; i.e., the specific immune response to hookworm vaccine antigens might be altered by infection with another helminth.

  9. Neutralization by Insulin of the Hypertensive Effect of Dermcidin Isoform 2: An Environmentally Induced Diabetogenic and Hypertensive Protein

    Science.gov (United States)

    Bank, Sarbashri; Bhattacharya, Rabindra; Khan, Nighat N.; Sinha, A. Kumar

    2014-01-01

    The effect of dermcidin isoform 2 (dermcidin), an environmentally induced stress protein, was investigated on the genesis of diabetes mellitus and hypertension, the two major atherosclerotic risk factors. The role of dermcidin as an atherosclerotic risk factor related to the impaired systemic insulin level was investigated. Dermcidin was prepared by electrophoresis using plasma from the subjects with acute ischemic heart disease. Injection of 0.2 μM dermcidin in mice increased the blood glucose level from 98 ± 2.45 mg/dL to 350  ± 10.2 mg/dL which was normalized by the oral administration of acetyl salicylic acid (aspirin) after 24 h. Hypertensive subjects with systolic and diastolic blood pressure of 165 mm and 95 mm of Hg, respectively, had plasma dermcidin level of 95 nM. Ingestion of acetyl salicylic acid (aspirin) (150 mg/70 kg body weight) decreased the systolic and diastolic pressures to 125 mm and 80 mm of Hg, respectively, with decrease of dermcidin level to 15 nM. Incubation of kidney cortex cells with 0.2 μM dermcidin-inhibited synthesis of (r)-cortexin, an antihypertensive protein, and the basal (r)-cortexin level was reduced from 33 nM to 15 nM. Addition of 25 μunits of insulin/mL was found to reverse the inhibition of cortexin synthesis. The effect of dermcidin as a diabetogenic and a hypertensive agent could be controlled either by aspirin or by insulin. PMID:24649391

  10. Neutralization by Insulin of the Hypertensive Effect of Dermcidin Isoform 2: An Environmentally Induced Diabetogenic and Hypertensive Protein

    Directory of Open Access Journals (Sweden)

    Rajeshwary Ghosh

    2014-01-01

    Full Text Available The effect of dermcidin isoform 2 (dermcidin, an environmentally induced stress protein, was investigated on the genesis of diabetes mellitus and hypertension, the two major atherosclerotic risk factors. The role of dermcidin as an atherosclerotic risk factor related to the impaired systemic insulin level was investigated. Dermcidin was prepared by electrophoresis using plasma from the subjects with acute ischemic heart disease. Injection of 0.2 μM dermcidin in mice increased the blood glucose level from 98±2.45 mg/dL to 350 ±10.2 mg/dL which was normalized by the oral administration of acetyl salicylic acid (aspirin after 24 h. Hypertensive subjects with systolic and diastolic blood pressure of 165 mm and 95 mm of Hg, respectively, had plasma dermcidin level of 95 nM. Ingestion of acetyl salicylic acid (aspirin (150 mg/70 kg body weight decreased the systolic and diastolic pressures to 125 mm and 80 mm of Hg, respectively, with decrease of dermcidin level to 15 nM. Incubation of kidney cortex cells with 0.2 μM dermcidin-inhibited synthesis of (r-cortexin, an antihypertensive protein, and the basal (r-cortexin level was reduced from 33 nM to 15 nM. Addition of 25 μunits of insulin/mL was found to reverse the inhibition of cortexin synthesis. The effect of dermcidin as a diabetogenic and a hypertensive agent could be controlled either by aspirin or by insulin.

  11. Synonymous Deoptimization of Foot-and-Mouth Disease Virus Causes Attenuation In Vivo while Inducing a Strong Neutralizing Antibody Response

    Science.gov (United States)

    Diaz-San Segundo, Fayna; Medina, Gisselle N.; Ramirez-Medina, Elizabeth; Velazquez-Salinas, Lauro; Koster, Marla; Grubman, Marvin J.

    2015-01-01

    ABSTRACT Codon bias deoptimization has been previously used to successfully attenuate human pathogens, including poliovirus, respiratory syncytial virus, and influenza virus. We have applied a similar technology to deoptimize the capsid-coding region (P1) of foot-and-mouth disease virus (FMDV). Despite the introduction of 489 nucleotide changes (19%), synonymous deoptimization of the P1 region rendered a viable FMDV progeny. The resulting strain was stable and reached cell culture titers similar to those obtained for wild-type (WT) virus, but at reduced specific infectivity. Studies in mice showed that 100% of animals inoculated with the FMDV A12 P1 deoptimized mutant (A12-P1 deopt) survived, even when the animals were infected at doses 100 times higher than the dose required to cause death by WT virus. All mice inoculated with the A12-P1 deopt mutant developed a strong antibody response and were protected against subsequent lethal challenge with WT virus at 21 days postinoculation. Remarkably, the vaccine safety margin was at least 1,000-fold higher for A12-P1 deopt than for WT virus. Similar patterns of attenuation were observed in swine, in which animals inoculated with A12-P1 deopt virus did not develop clinical disease until doses reached 1,000 to 10,000 times the dose required to cause severe disease in 2 days with WT A12. Consistently, high levels of antibody titers were induced, even at the lowest dose tested. These results highlight the potential use of synonymous codon pair deoptimization as a strategy to safely attenuate FMDV and further develop live attenuated vaccine candidates to control such a feared livestock disease. IMPORTANCE Foot-and-mouth disease (FMD) is one of the most feared viral diseases that can affect livestock. Although this disease appeared to be contained in developed nations by the end of the last century, recent outbreaks in Europe, Japan, Taiwan, South Korea, etc., have demonstrated that infection can spread rapidly, causing

  12. Neutralizing antibodies induced by recombinant virus-like particles of enterovirus 71 genotype C4 inhibit infection at pre- and post-attachment steps.

    Directory of Open Access Journals (Sweden)

    Zhiqiang Ku

    Full Text Available BACKGROUND: Enterovirus 71 (EV71 is a major causative agent of hand, foot and mouth disease, which has been prevalent in Asia-Pacific regions, causing significant morbidity and mortality in young children. Antibodies elicited by experimental EV71 vaccines could neutralize infection in vitro and passively protect animal models from lethal challenge, indicating that neutralizing antibodies play an essential role in protection. However, how neutralizing antibodies inhibit infection in vitro remains unclear. METHODS/FINDINGS: In the present study, we explored the mechanisms of neutralization by antibodies against EV71 virus-like particles (VLPs. Recombinant VLPs of EV71 genotype C4 were produced in insect cells using baculovirus vectors. Immunization with the VLPs elicited a high-titer, EV71-specific antibody response in mice. Anti-VLP mouse sera potently neutralized EV71 infection in vitro. The neutralizing antibodies in the anti-VLP mouse sera were found to target mainly an extremely conserved epitope (FGEHKQEKDLEYGAC located at the GH loop of the VP1 protein. The neutralizing anti-VLP antisera were able to inhibit virus binding to target cells efficiently. In addition, post-attachment treatment of virus-bound cells with the anti-VLP antisera also neutralized virus infection, although the antibody concentration required was higher than that of the pre-attachment treatment. CONCLUSIONS: Collectively, our findings represent a valuable addition to the understanding of mechanisms of EV71 neutralization and have strong implications for EV71 vaccine development.

  13. Mass spectrometry of oligopeptides in the presence of large amounts of alkali halides using desorption/ionization induced by neutral cluster impact.

    Science.gov (United States)

    Portz, André; Baur, Markus; Gebhardt, Christoph R; Dürr, Michael

    2016-06-01

    Oligopeptides in the presence of large amounts of salt were desorbed and ionized using desorption/ionization induced by neutral clusters (DINeC) for further analysis by means of mass spectrometry (MS). Using oligopeptides in alkali halide solutions as a model system, DINeC was shown to yield clear and fragmentation free mass spectra of the biomolecules even from environments with a large excess of salt. The results were traced back to a phase separation between salt and biomolecules during sample preparation. The ratio between alkali metal complexes [M+A](+) and bare biomolecules [M+H](+) was controlled using different preparation schemes. DINeC was applied to the products of a tryptic digest of bovine serum albumin in the presence of sodium chloride; the results of a mass fingerprint analysis did not show a major difference for the spectra with and without salt in the original solution. The metal-ion/peptide interaction was further investigated by means of tandem-MS. PMID:26825286

  14. Measurements of plasma temperature and electron density in laser-induced copper plasma by time-resolved spectroscopy of neutral atom and ion emissions

    Indian Academy of Sciences (India)

    V K Unnikrishnan; Kamlesh Alti; V B Kartha; C Santhosh; G P Gupta; B M Suri

    2010-06-01

    Plasma produced by a 355 nm pulsed Nd:YAG laser with a pulse duration of 6 ns focussed onto a copper solid sample in air at atmospheric pressure is studied spectroscopically. The temperature and electron density characterizing the plasma are measured by time-resolved spectroscopy of neutral atom and ion line emissions in the time window of 300–2000 ns. An echelle spectrograph coupled with a gated intensified charge coupled detector is used to record the plasma emissions. The temperature is obtained using the Boltzmann plot method and the electron density is determined using the Saha– Boltzmann equation method. Both parameters are studied as a function of delay time with respect to the onset of the laser pulse. The results are discussed. The time window where the plasma is optically thin and is also in local thermodynamic equilibrium (LTE), necessary for the laser-induced breakdown spectroscopy (LIBS) analysis of samples, is deduced from the temporal evolution of the intensity ratio of two Cu I lines. It is found to be 700–1000 ns.

  15. Hexachlorobenzene-induced alterations on neutral and acidic sphingomyelinases and serine palmitoyltransferase activities. A time course study in two strains of rats.

    Science.gov (United States)

    Billi de Catabbi, S C; Setton-Advruj, C P; Sterin-Speziale, N; San Martín de Viale, L C; Cochón, A C

    2000-08-21

    Hexachlorobenzene (HCB) induces porphyria both in humans and rodents, and hepatocarcinoma in rodents. In a previous work we observed that HCB produces a continuous decrease in hepatic sphingomyelin (SM) content in Wistar rats. A distinguishing characteristic of sphingolipids breakdown products is their participation in anti-proliferative and apoptotic processes and in the suppression of oncogenesis. As a first step to elucidate the role of SM decrease in the hepatotoxicity induced by HCB, the present study evaluates the metabolic causes of the continuous decrease in hepatic SM content observed in Wistar rats with HCB intoxication, and its relation with porphyria development. For this purpose, the time-course (3, 7, 15, 21 and 28 days) of the effects of HCB on hepatic SM levels and on some of the enzymes of SM synthesis (serine palmitoyltransferase, SPT) and catabolism (sphingomyelinases, SMases) was followed, using two strains of rats differing in their susceptibility to acquire porphyria: Chbb THOM (low) and Wistar (high). HCB (1 g kg(-1) b.w. per day) was administered by gastric intubation as an aqueous suspension. After 5 days of HCB treatment, animals were allowed a 2-day recovery period without HCB administration. Two phases in the HCB-induced damages to sphingolipid metabolism were observed. The first stage (7 days of treatment), common to both strains of rats, was characterized by a decrease in hepatic SM levels (17-25%) and in SPT activity (50-43%), while strain differences were found for the later stage. In Chbb THOM rats, hepatic SM content was restored to normal values concomitantly with an increase in SPT activity (44%, at day 28), and without any increase in SM catabolism. In addition, the level of the other phospholipids was not altered. In Wistar rats, hepatic SM levels decreased continuously throughout the experiment, accompanied by increases in SPT, acidic sphingomyelinase (A-SMase) and neutral sphingomyelinase (N-SMase) activities (86, 28.5 and 78

  16. Gonadotrophin-releasing hormone in winter flounder (Pseudopleuronectes americanus): molecular characterization, distribution and effects of fasting.

    Science.gov (United States)

    Tuziak, Sarah M; Volkoff, Hélène

    2013-04-01

    Gonadotrophin-releasing hormone (GnRH) is primarily related to reproductive processes in vertebrates. However other physiological roles, including functions in food intake regulation and energy status, have been demonstrated for GnRH in animals. The ten amino acid active peptide is relatively conserved throughout chordates, more specifically in fish species. Teleosts generally have at least two variants of GnRH present in their genomes. GnRH2 (commonly termed chicken-GnRH) is common to all fish, whereas other prevalent forms include GnRH1 and/or GnRH3 (also known as salmon-GnRH). The mRNAs of all three forms were identified in winter flounder (Pseudopleuronectes americanus). Winter flounder GnRH1 appears to be ubiquitously and strongly expressed throughout the brain. GnRH2 mRNA is highly expressed in the optic tectum/thalamus. Finally, GnRH3 mRNA is expressed throughout the brain, but not in the pituitary, with apparent highest expression in the telencephalon/preoptic area. Flounder GnRH1 mRNA is found in most peripheral tissues examined, including the foregut, midgut and gonads. GnRH2 mRNA appears to be expressed throughout the periphery, with apparent highest transcript expression in male gonads. Finally, winter flounder GnRH3 transcript is found at low levels in the skin, heart, and gonads. The effect of fasting on the expression of each of the three isoforms was assessed. Fasting reduces GnRH2 and GnRH3 mRNA expression in the optic tectum/thalamus and hypothalamus, and telencephalon/preoptic area, respectively, compared with fed fish. GnRH1 mRNA expression does not appear to be altered by feeding status. GnRH mRNAs do not seem to regulate food intake peripherally through the gut based on our preliminary findings. Our preliminary results suggest that the GnRH system could play a central role in food intake regulation of winter flounder. PMID:23298570

  17. ISOLATION AND GENETIC CHARACTERIZATION OF TOXOPLASMA GONDII FROM RACCOONS (PROCYON LOTOR), CATS (FELIS DOMESTICUS), STRIPED SKUNK (MEPHITIS MEPHITIS), BLACK BEAR (URSUS AMERICANUS), AND COUGAR (PUMA CONCOLOR) FROM CANADA

    Science.gov (United States)

    Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats ( Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus ) from Kuujjuaq, northern Quebec, Canada. Geno...

  18. A regulatory hydrophobic area in the flexible joint region of plasminogen activator inhibitor-1, defined with fluorescent activity-neutralizing ligands. Ligand-induced serpin polymerization

    DEFF Research Database (Denmark)

    Egelund, R; Einholm, A P; Pedersen, K E; Nielsen, R W; Christensen, A; Deinum, J; Andreasen, Peter A

    2001-01-01

    all tested nonfluorescent neutralizers, indicating that all neutralizers bind to a common hydrophobic area preferentially accessible in active PAI-1. Activity neutralization proceeded through two consecutive steps as follows: first step is conversion to forms displaying substrate behavior toward u...... having overlapping, but not identical, binding sites in the region around alpha-helices D and E and beta-strand 1A, known to act as a flexible joint when beta-sheet A opens and the reactive center loop inserts as beta-strand 4A during reaction with target proteinases. The defined binding area may be a...

  19. Terahertz-induced depletion of the ground-state population of neutral donors in GaAs measured by resonant elastic light scattering from donor-bound excitons

    CERN Document Server

    Allen, D G; Sherwin, M S

    2005-01-01

    Strong resonant elastic light scattering (RELS) from the donor-bound exciton transition in GaAs (1.514eV) occurs at neutral donors in the ground (1S) state, but not at neutral donors in excited hydrogenic states. When 1.6 THz radiation is incident on an ensemble of neutral donors, we observe up to a 30% decrease in the RELS, corresponding to a decrease in the population of neutral donors in their ground states. This optical detection method is similar to quantum nondemolition measurement techniques used for readout of ion trap quantum computers and diamond nitrogen-vacancy centers. In this scheme, Auger recombination of the bound exciton, which changes the state of the donor during measurement, limits the measurement fidelity and maximum NIR excitation intensity.

  20. Clearance of Genotype 1b Hepatitis C Virus in Chimpanzees in the Presence of Vaccine-Induced E1-Neutralizing Antibodies

    OpenAIRE

    Babs E Verstrepen; Depla, Erik; Rollier, Christine S.; Mares, Gwenny; Drexhage, Joost A. R.; Priem, Sofie; Ernst J Verschoor; Koopman, Gerrit; Granier, Christelle; Dreux, Marlène; Cosset, François L.; Maertens, Geert; Heeney, Jonathan L.

    2011-01-01

    Accumulating evidence indicates that neutralizing antibodies play an important role in protection from chronic hepatitis C virus (HCV) infection. Efforts to elicit such responses by immunization with intact heterodimeric E1E2 envelope proteins have met with limited success. To determine whether antigenic sites, which are not exposed by the combined E1E2 heterodimer structure, are capable of eliciting neutralizing antibody responses, we expressed and purified each as separate recombinant prote...

  1. "Unconventional" Neutralizing Activity of Antibodies Against HIV

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Neutralizing antibodies are recognized to be one of the essential elements of the adaptive immune response that must be induced by an effective vaccine against HIV. However, only a limited number of antibodies have been identified to neutralize a broad range of primary isolates of HIV-1 and attempts to induce such antibodies by immunization were unsuccessful. The difficulties to generate such antibodies are mainly due to intrinsic properties of HIV-1 envelope spikes, such as high sequence diversity, heavy glycosylation, and inducible and transient nature of certain epitopes. In vitro neutralizing antibodies are identified using "conventional" neutralization assay which uses phytohemagglutinin (PHA)-stimulated human PBMCs as target cells. Thus, in essence the assay evaluates HIV-1 replication in CD4+ T cells. Recently, several laboratories including us demonstrated that some monoclonal antibodies and HIV-1-specific polyclonal IgG purified from patient sera, although they do not have neutralizing activity when tested by the "conventional" neutralization assay, do exhibit potent and broad neutralizing activity in "unconventional" ways. The neutralizing activity of these antibodies and IgG fractions is acquired through post-translational modifications, through opsonization of virus particles into macrophages and immature dendritic cells (iDCs), or through expression of antibodies on the surface of HIV-1-susceptible cells. This review will focus on recent findings of this area and point out their potential applications in the development of preventive strategies against HIV.

  2. Persistent Bovine Viral Diarrhea Virus Infection in Domestic and Wild Small Ruminants and Camelids Including the Mountain Goat (Oreamnos americanus)

    Science.gov (United States)

    Nelson, Danielle D.; Duprau, Jennifer L.; Wolff, Peregrine L.; Evermann, James F.

    2016-01-01

    Bovine viral diarrhea virus (BVDV) is a pestivirus best known for causing a variety of disease syndromes in cattle, including gastrointestinal disease, reproductive insufficiency, immunosuppression, mucosal disease, and hemorrhagic syndrome. The virus can be spread by transiently infected individuals and by persistently infected animals that may be asymptomatic while shedding large amounts of virus throughout their lifetime. BVDV has been reported in over 40 domestic and free-ranging species, and persistent infection has been described in eight of those species: white-tailed deer, mule deer, eland, mousedeer, mountain goats, alpacas, sheep, and domestic swine. This paper reviews the various aspects of BVDV transmission, disease syndromes, diagnosis, control, and prevention, as well as examines BVDV infection in domestic and wild small ruminants and camelids including mountain goats (Oreamnos americanus). PMID:26779126

  3. Alteration of reproductive steroids of male winter flounder (Pleuronectes americanus) chronically exposed to low levels of crude oil in sediments

    International Nuclear Information System (INIS)

    When male winter flounder (Pleuronectes americanus) were held in seawater for 4 months exposed to sand treated with five low levels of crude oil, there was a significant reduction in testosterone and 11-ketotestosterone glucuronides in blood plasma. At the two higher levels of oil the concentration of plasma glucuronides were similar but very significantly lower than the controls or the three lower concentrations of oil. For both androgens the ratio of glucuronides to free steroids declined in a stepwise fashion. Free testosterone and 11-ketotestosterone plasma levels were not significantly affected by any concentration of oil in the sediment. Liver weights as a percentage of body weight were significantly increased at the two highest levels of oil in sediments, but neither body weights nor testes weights were altered by exposure to oil. It has been suggested that androgen glucuronides can function as pheromones in some fish and this is one potentially deleterious effect of exposure to oil. 33 refs., 1 tab

  4. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    Science.gov (United States)

    Puckett, Emily E; Etter, Paul D; Johnson, Eric A; Eggert, Lori S

    2015-09-01

    Studies of species with continental distributions continue to identify intraspecific lineages despite continuous habitat. Lineages may form due to isolation by distance, adaptation, divergence across barriers, or genetic drift following range expansion. We investigated lineage diversification and admixture within American black bears (Ursus americanus) across their range using 22 k single nucleotide polymorphisms and mitochondrial DNA sequences. We identified three subcontinental nuclear clusters which we further divided into nine geographic regions: Alaskan (Alaska-East), eastern (Central Interior Highlands, Great Lakes, Northeast, Southeast), and western (Alaska-West, West, Pacific Coast, Southwest). We estimated that the western cluster diverged 67 ka, before eastern and Alaskan divergence 31 ka; these divergence dates contrasted with those from the mitochondrial genome where clades A and B diverged 1.07 Ma, and clades A-east and A-west diverged 169 ka. We combined estimates of divergence timing with hindcast species distribution models to infer glacial refugia for the species in Beringia, Pacific Northwest, Southwest, and Southeast. Our results show a complex arrangement of admixture due to expansion out of multiple refugia. The delineation of the genomic population clusters was inconsistent with the ranges for 16 previously described subspecies. Ranges for U. a. pugnax and U. a. cinnamomum were concordant with admixed clusters, calling into question how to order taxa below the species level. Additionally, our finding that U. a. floridanus has not diverged from U. a. americanus also suggests that morphology and genetics should be reanalyzed to assess taxonomic designations relevant to the conservation management of the species. PMID:25989983

  5. Crystallization and preliminary X-ray analysis of Na-SAA-2 from the human hookworm parasite Necator americanus

    International Nuclear Information System (INIS)

    The purification, crystallization and preliminary X-ray diffraction analysis of a surface-associated antigen from the major human hookworm N. americanus is presented. Human hookworms are among the most pathogenic soil-transmitted helminths. These parasitic nematodes have co-evolved with the host and are able to maintain a high worm burden for decades without killing the human host. However, it is possible to develop vaccines against laboratory-challenge hookworm infections using either irradiated third-state infective larvae (L3) or enzymes from the adult parasites. In an effort to control hookworm infection globally, the Human Hookworm Vaccine Initiative, a product-development partnership with the Sabin Vaccine Institute to develop new control tools including vaccines, has identified a battery of protein antigens, including surface-associated antigens (SAAs) from L3. SAA proteins are characterized by a 13 kDa conserved domain of unknown function. SAA proteins are found on the surface of infective L3 stages (and some adult stages) of different nematode parasites, suggesting that they may play important roles in these organisms. The atomic structures and function of SAA proteins remain undetermined and in an effort to remedy this situation recombinant Na-SAA-2 from the most prevalent human hookworm parasite Necator americanus has been expressed, purified and crystallized. Useful X-ray data have been collected to 2.3 Å resolution from a crystal that belonged to the monoclinic space group C2 with unit-cell parameters a = 73.88, b = 35.58, c = 42.75 Å, β = 116.1°

  6. Hookworm infection and anemia in adult women in rural Chiapas, Mexico Anemia e infección por Necator americanus en mujeres en Chiapas, México

    Directory of Open Access Journals (Sweden)

    Paula E. Brentlinger

    2003-04-01

    Full Text Available OBJECTIVE: To describe associations between anemia and hookworm (Necator americanus infection in hospitalized women in rural Chiapas, Mexico. MATERIAL AND METHODS: We retrospectively reviewed the hospital records of 68 anemic women (defined as having a hemoglobin level OBJETIVO: Describir la asociación entre anemia severa e infección con Necator americanus en una población de mujeres hospitalizadas en el estado de Chiapas, México. MATERIAL Y MÉTODOS: En el registro de ingresos del año 1999 de un hospital rural en Altamirano, Chiapas, se identificaron a las pacientes con diagnósticos de egreso de anemia (definida como hemoglobina<10mg/dl y/o parasitosis intestinal. También se revisó el registro de transfusiones para identificar a las mujeres mayores de 14 años de edad que recibieron sangre. La revisión de expedientes y el análisis de datos se llevó a cabo en el año 2000. Las comparaciones de las características de las pacientes se hicieron con la prueba t de Student (para variables continuas y la prueba ji2 (para variables categóricas. La significancia estadística se estableció con un valor de p< 0.01. RESULTADOS: En las mujeres en quienes se realizó examen coproscópico, 50% tuvieron N. americanus. La presencia de N. americanus no excluyó la presencia de otro factor de riesgo para anemia, por ejemplo embarazo o hemorragia. Los niveles de hemoglobina de las mujeres infectadas con N. americanus fueron significativamente más bajos (promedio 4.1 g/dl que los de las demás mujeres anémicas (promedio 7.0 gm/dl, y la prevalencia de N. americanus en mujeres anémicas fue más alta (50.0% que en la población atendida por el hospital (1.9%. CONCLUSIONES: Aunque la prevalencia de infección con N. americanus no se considera alta en la población general mexicana, fue importante en las mujeres anémicas que se sometieron a coproscopía en nuestro estudio. Las mujeres anémicas ameritan coproscopía donde existe N. americanus, y pueden

  7. Occurrence of Larvae and Juveniles of Eucinostomus argenteus, Eucinostomus gula, Menticirrhus americanus, Menticirrhus littoralis, Umbrina coroides and Micropogonias furnieri at Pontal do Sul beach, Paraná

    Directory of Open Access Journals (Sweden)

    Rodrigo Santiago Godefroid

    2001-12-01

    Full Text Available Despite its importance, most ichthyoplankton studies in the South-Southeastern coast of Brazil, have been accomplished on the continental shelf. Regarding the beach environment, recognized as a nursery, little is known about the ichthyoplankton. We analyzed 288 samples collected with a 18 by 2 m seine net, 1 mm mesh and a conical plankton net, with a mesh of 300 mum and a 60 cm mouth. Eucinostomus argenteus comprised 78 % of the larvae and juveniles caught in the samples. The occurrence of gerreids was strongly concentrated in the summer, while the Menticirrhus littoralis, Menticirrhus americanus and Umbrina coroides were present during all seasons. M.littoralis was most abundant during spring, while M. americanus and U. coroides dominated during winter. For all species, the largest captures occurred during low tide. Environmental preferences are indicated in the principal component analysis, with the larvae and juveniles of E. argenteus and E. gula positively correlated with smaller waves and smaller morphodynamism, whereas M. americanus, U. coroides and M. furnieri seem to prefer periods with lower temperatures and larger morphodynamism.Apesar da importância, a maioria dos estudos de ictioplâncton na costa sul-sudeste do Brasil, foram realizados sobre a plataforma continental. No que se refere ao ambiente praial, reconhecido como área de criação, pouco se sabe sobre o ictioplâncton. Foram analisadas 288 amostras coletadas com uma rede tipo picaré com 18 x 2 m e malha de 1mm, e rede de plancton cônica, com malha de 300 mim e boca de 60 cm. A espécie E. argenteus totalizou 78 % das larvas e juvenis capturados. A ocorrência dos gerreideos foi fortemente concentrada no verão, enquanto que Menticirrhus littoralis, Menticirrhus americanus e Umbrina coroides estiveram presentes em todas as estações do ano. M. littoralis foi mais abundante na primavera, enquanto que M. americanus e U. coroides dominaram no inverno. Em todas as esp

  8. Application of random amplified polymorphic DNA (RAPD) analysis for identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets.

    Science.gov (United States)

    Asensio, Luis; González, Isabel; Fernández, Alicia; Rodríguez, Miguel A; Lobo, Esther; Hernández, Pablo E; García, Teresa; Martín, Rosario

    2002-02-01

    A random amplified polymorphic DNA (RAPD) method was developed for the specific identification of grouper (Epinephelus guaza), wreck fish (Polyprion americanus), and Nile perch (Lates niloticus) fillets. Using two different reaction primers (S1 and L1), RAPD analysis produced clear fingerprints from which the three fish species could be easily identified. This approach is rapid and reliable and offers the potential to detect fraudulent or unintentional mislabeling of these species in routine seafood authentication analysis. PMID:11848581

  9. Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines

    DEFF Research Database (Denmark)

    Faust, Helena; Nielsen, Lars Toft; Sehr, Peter;

    2016-01-01

    neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil......™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were <1 international unit (IU) in 87% of study subjects before vaccination but >10IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil......™ vaccination for >50% of vaccinated females for HPV 31, 35 and 73 and for >50% of Cervarix™-vaccinated females forHPV 31, 33, 35, 45, 56 and 58. Cross-reactivity with non-genital HPV types was also detected. In conclusion, HIV-infected subjects responded to HPV vaccination with induction of neutralizing...

  10. Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines

    DEFF Research Database (Denmark)

    Faust, Helena; Nielsen, Lars Toft; Sehr, Peter;

    2016-01-01

    Ninety-one HIV-infected individuals (61 men and 30 women) were randomized to vaccination either with quadrivalent (Gardasil™) or bivalent (Cervarix™) HPV vaccine. Neutralizing and specific HPV-binding serum antibodies were measured at baseline and 12 months after the first vaccine dose. Presence...... of neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil......™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were 10IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil...

  11. Foot-and-Mouth Disease Virus neutralizing antibodies production induced by pcDNA3 and Sindbis virus based plasmid encoding FMDV P1-2A3C3D in swine.

    OpenAIRE

    Dory, Daniel; Rémond, Michelle; Béven, Véronique; Cariolet, Roland; Zientara, Stephan; Jestin, André

    2009-01-01

    International audience DNA vaccination against Foot-and-Mouth Disease Virus (FMDV) is an attractive and alternative strategy to the use of classical inactivated viral vaccines. The injection of a pcDNA3.1-based DNA vaccine encoding for FMDV P1-2A3C3D and GM-CSF proteins had previously been shown to induce the production of neutralizing antibodies against FMDV and partially protect swine against an experimental challenge. Based on the induction of FMDV humoral immune responses, the aim of t...

  12. The fission yeast mitotic activator cdc25 and sucrose induce early flowering synergistically in the day-neutral Nicotiana tabacum cv. Samsun

    Czech Academy of Sciences Publication Activity Database

    Teichmanová, M.; Mašková, P.; Vojvodová, P.; Krekule, Jan; Francis, D.; Lipavská, H.

    2007-01-01

    Roč. 176, č. 4 (2007), s. 804-812. ISSN 0028-646X Grant ostatní: Grantová agentura UK(CZ) 133/2000 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : cdc25 gene * cell cycle regulation * day neutral tobacco Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.249, year: 2007

  13. Search for neutral leptons

    International Nuclear Information System (INIS)

    At present we know of three kinds of neutral leptons: the electron neutrino, the muon neutrino, and the tau neutrino. This paper reviews the search for additional neutral leptons. The method and significance of a search depends upon the model used for the neutral lepton being sought. Some models for the properties and decay modes of proposed neutral leptons are described. Past and present searches are reviewed. The limits obtained by some completed searches are given, and the methods of searches in progress are described. Future searches are discussed. 41 references

  14. Charm Changing Neutral Currents and Supersymmetry

    OpenAIRE

    Lau, Kwong

    2003-01-01

    Flavor changing neutral currents (FCNCs) in the charm system are highly suppressed in the standard model (SM). The theoretical strategies used to suppress FCNCs induced by supersymmetry in the strange and beauty systems need not apply to the charm system. The charm changing neutral current decay D^0-> mu^+ mu^- is studied phenomenologically in the framework of supersymmetric extensions of the standard model. It is found that the decay branching ratio can be enhanced to about 10^{-10}, by havi...

  15. Radiative lifetimes of neutral neodymium

    International Nuclear Information System (INIS)

    This work is part of an on-going study of radiative properties of rare earth neutral atoms. This work is motivated by research needs in several disparate fields including astrophysics and lighting technology. Radiative lifetimes of 100 levels of neutral neodymium are measured using the technique of time-resolved laser-induced fluorescence on a slow atomic beam. Of the 100 levels, 3 are even parity ranging in energy from 25 746 to 26 835 cm-1, and the remaining 97 are odd parity ranging from 17 787 to 27 786 cm-1. This set of Nd i lifetimes represents a significant extension to the available published data, with 51 of the 100 level lifetimes measured for the first time. These data, which are accurate to ±5%, provide the absolute normalization for a large set of measured Nd i transition probabilities.

  16. Radiative lifetimes of neutral gadolinium

    Energy Technology Data Exchange (ETDEWEB)

    Den Hartog, E A; Bilty, K A; Lawler, J E, E-mail: eadenhar@wisc.edu, E-mail: biltyka@uwec.edu, E-mail: jelawler@wisc.edu [Department of Physics, University of Wisconsin, 1150 University Ave, Madison, WI 53706 (United States)

    2011-03-14

    The current work is part of an ongoing study of radiative properties of rare earth neutral atoms motivated by research needs in several disparate fields including astrophysics, laser chemistry and lighting technology. Time-resolved laser-induced fluorescence on a slow atomic beam has been used to measure radiative lifetimes, accurate to {+-}5%, for 136 levels of neutral gadolinium. Of the 136 levels, 6 are odd parity ranging in energy from 32 929 to 36 654 cm{sup -1}, and the remaining 130 are even parity ranging from 17 750 to 34 175 cm{sup -1}. This set of Gd i lifetimes represents a significant extension to the available published data, with 93 of the 136 level lifetimes measured for the first time. These lifetimes will provide the absolute normalization for a large set of measured Gd i transition probabilities.

  17. Radiative lifetimes of neutral gadolinium

    International Nuclear Information System (INIS)

    The current work is part of an ongoing study of radiative properties of rare earth neutral atoms motivated by research needs in several disparate fields including astrophysics, laser chemistry and lighting technology. Time-resolved laser-induced fluorescence on a slow atomic beam has been used to measure radiative lifetimes, accurate to ±5%, for 136 levels of neutral gadolinium. Of the 136 levels, 6 are odd parity ranging in energy from 32 929 to 36 654 cm-1, and the remaining 130 are even parity ranging from 17 750 to 34 175 cm-1. This set of Gd i lifetimes represents a significant extension to the available published data, with 93 of the 136 level lifetimes measured for the first time. These lifetimes will provide the absolute normalization for a large set of measured Gd i transition probabilities.

  18. Radiative lifetimes of neutral samarium

    International Nuclear Information System (INIS)

    Radiative lifetimes of 120 odd-parity levels of neutral samarium, ranging in energy from 17 190 to 33 507 cm−1, are measured using the technique of time-resolved laser-induced fluorescence on a slow atomic beam. This work is part of an ongoing study of radiative properties of rare earth neutral atoms, and is motivated by research needs in astrophysics and lighting technology. This set of Sm i lifetimes substantially increases the available published lifetime data, with 49 of the 120 level lifetimes measured for the first time. These data, most of which are accurate to ±5%, will be combined with branching fractions determined from Fourier transform spectroscopy to produce a large set of measured Sm i transition probabilities. (paper)

  19. Immunization of rabbits with highly purified, soluble, trimeric human immunodeficiency virus type 1 envelope glycoprotein induces a vigorous B cell response and broadly cross-reactive neutralization.

    Directory of Open Access Journals (Sweden)

    Gerald V Quinnan

    Full Text Available Previously we described induction of cross-reactive HIV-1 neutralizing antibody responses in rabbits using a soluble HIV-1 gp140 envelope glycoprotein (Env in an adjuvant containing monophosphoryl lipid A (MPL and QS21 (AS02A. Here, we compared different forms of the same HIV-1 strain R2 Env for antigenic and biophysical characteristics, and in rabbits characterized the extent of B cell induction for specific antibody expression and secretion and neutralizing responses. The forms of this Env that were produced in and purified from stably transformed 293T cells included a primarily dimeric gp140, a trimeric gp140 appended to a GCN4 trimerization domain (gp140-GCN4, gp140-GCN4 with a 15 amino acid flexible linker between the gp120 and gp41 ectodomain (gp140-GCN4-L, also trimeric, and a gp140 with the flexible linker purified from cell culture supernatants as either dimer (gp140-L(D or monomer (gp140-L(M. Multimeric states of the Env proteins were assessed by native gel electrophoresis and analytical ultracentrifugation. The different forms of gp140 bound broadly cross-reactive neutralizing (BCN human monoclonal antibodies (mAbs similarly in ELISA and immunoprecipitation assays. All Envs bound CD4i mAbs in the presence and absence of sCD4, as reported for the R2 Env. Weak neutralization of some strains of HIV-1 was seen after two additional doses in AS02A. Rabbits that were given a seventh dose of gp140-GCN4-L developed BCN responses that were weak to moderate, similar to our previous report. The specificity of these responses did not appear similar to that of any of the known BCN human mAbs. Induction of spleen B cell and plasma cells producing immunoglobulins that bound trimeric gp140-GCN4-L was vigorous, based on ELISpot and flow cytometry analyses. The results demonstrate that highly purified gp140-GCN4-L trimer in adjuvant elicits BCN responses in rabbits accompanied by vigorous B cell induction.

  20. PROPAGACIÓN POR ESTACAS JUVENILES DEL BALSO BLANCO (Heliocarpus americanus L. Sin. H. popayanensis UTILIZANDO PROPAGADORES DE SUBIRRIGACIÓN PROPAGATION OF WHITE BALSUM (Heliocarpus americanus L. Sin. H. popayanensis CUTTINGS USING NONMIST PROPAGATORS

    Directory of Open Access Journals (Sweden)

    Carolina Vásquez Restrepo

    2006-12-01

    Full Text Available El mercado mundial de edulcorantes orgánicos es una oportunidad para la panela, producto básico de la canasta familiar que representa ingresos importantes para la población rural colombiana. El balso blanco (Heliocarpus americanus L. Sin. H. popayanensis Hook & Arn. es la especie más usada en procesos de clarificación de la panela en Antioquia y las zonas cañeras húmedas colombianas. Pero la extracción de la corteza de árboles obtenidos de la regeneración natural comienza a ser insostenible, por el daño causado a los individuos y la presión creciente a este recurso. La prohibición del uso de sustancias químicas en procesos de clarificación de panela ha aumentado la demanda de la corteza del balso blanco. En este trabajo se estimó el enraizamiento de estacas juveniles de balso blanco, por propagadores de subirrigación. Se realizaron dos experimentos, utilizando ácido anaftalenacético (ANA. En el primero se evaluó el efecto del transporte, cicatrizante y sustrato sobre el enraizamiento de las estacas de balso blanco. El mejor medio de transporte fue en cristales de hidrogel para mantener la humedad de las estacas, sin utilizar cicatrizante y sembrándolas en el sustrato tierra (55 % de enraizamiento. En el segundo se analizó la influencia de la intensidad lumínica y el área foliar en el porcentaje de enraizamiento de las estacas. El más alto enraizamiento se obtuvo con el tratamiento de doble sombra y un área foliar de 20 cm² (25 % de enraizamiento. Aunque los mejores resultados indican un relativo éxito en el uso de medios de enraizamiento, es una primera aproximación para propagar esta especie que necesita ser protegida.The world market of organic edulcorants is an opportunity for “panela”, a basic domestic consumption product that provides important income to rural population. White balsum (Heliocarpus americanus L. Sin. H. popayanensis Hook & Arn. is the most used species in the panela clarification processes in

  1. Evidence for existence and compactness of DNA superstructure units in mammalian cells: A microdosimetric approach to radiation - induced DNA release assayed by neutral sucrose gradient sedimentation

    International Nuclear Information System (INIS)

    Experimental results obtained with the neutral sucrose gradient sedimentation techniques of analysing mammalian DNA after irradiation in vivo (Chinese hamster cells V79) are evaluated theoretically in order to verify and extend a model by Ormerod and Lehmann that describes the gradual release of free DNA from the DNA-membrane complex. The model is based on the idea of chromatin organization in the form of membrane attached superstructure unit (MASSUs) defined by consecutive attachment points in intervals of M0 (DNA molecular weight of a MASSU). DNA sedimentation after cell lysis with sarkosyl as detergent allows good separation of the released free DNA from that remaining in the complex. The dose-dependence of both the percentage of DNA released and pertinent molecular weight parameters as measured with X-rays and derived from the model confirms it and yields the MASSU size M0=2.4x109 g/mol. (orig./WL)

  2. A niche for neutrality.

    Science.gov (United States)

    Adler, Peter B; Hillerislambers, Janneke; Levine, Jonathan M

    2007-02-01

    Ecologists now recognize that controversy over the relative importance of niches and neutrality cannot be resolved by analyzing species abundance patterns. Here, we use classical coexistence theory to reframe the debate in terms of stabilizing mechanisms (niches) and fitness equivalence (neutrality). The neutral model is a special case where stabilizing mechanisms are absent and species have equivalent fitness. Instead of asking whether niches or neutral processes structure communities, we advocate determining the degree to which observed diversity reflects strong stabilizing mechanisms overcoming large fitness differences or weak stabilization operating on species of similar fitness. To answer this question, we propose combining data on per capita growth rates with models to: (i) quantify the strength of stabilizing processes; (ii) quantify fitness inequality and compare it with stabilization; and (iii) manipulate frequency dependence in growth to test the consequences of stabilization and fitness equivalence for coexistence. PMID:17257097

  3. Ultracold Neutral Plasmas

    OpenAIRE

    Killian, T. C.; Pattard, T.; Pohl, T.; Rost, J. M.

    2006-01-01

    Ultracold neutral plasmas, formed by photoionizing laser-cooled atoms near the ionization threshold, have electron temperatures in the 1-1000 kelvin range and ion temperatures from tens of millikelvin to a few kelvin. They represent a new frontier in the study of neutral plasmas, which traditionally deals with much hotter systems, but they also blur the boundaries of plasma, atomic, condensed matter, and low temperature physics. Modelling these plasmas challenges computational techniques and ...

  4. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus.

    Directory of Open Access Journals (Sweden)

    Diana J R Lafferty

    Full Text Available Increasingly, measures of glucocorticoid levels (e.g., cortisol, key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116 as an ecological model and hair cortisol concentration (HCC as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD] and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD. We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges.

  5. Cell-stage-specific enhancement by caffeine of the frequency of chromatid aberrations induced by X-rays in neutral ganglia of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Caffeine (10-2 M) induced a high level of chromatid aberrations in neural ganglia of third-instar larvae of Drosophila melanogaster only when it was added to cells in late G2 and mitotic prophase. No aberrations were observed after treatment in late S-middle G2 or C-mitosis. We observed that, in these stages, caffeine strongly increased X-ray-induced damage (500 R). This potentiation was quantitatively similar. But it involved all types of aberration after treatment in C-mitosis, and essentially isochromatid deletions and chromatid exhanges after treatment in S-G2. Some hypotheses are put forth to explain the possible mechanism of action of caffeine in the potentiation of X-ray-induced damage. (orig.)

  6. Radiation-induced DNA double-strand breaks produced in histone-depleted tumor cell nuclei measured using the neutral comet assay

    International Nuclear Information System (INIS)

    Removal of histones and other nuclear proteins greatly enhances the sensitivity of mammalian cells to DNA damage by ionizing radiation. We examined the possibility that the ease of dissociation of histones, or the association of other nuclear proteins with DNA, may differ between radioresistant and sensitive human tumor cells. Cells embedded in agarose were exposed to increasing salt concentrations prior to irradiation and examination using a microscopic gel electrophoresis method, the neutral comet assay. Induction of double-strand breaks increased by a factor of about 20 when cells of four human tumor cell line HT144 melanoma, HT29 adenocarcinoma, DU145 prostate carcinoma and U87 glioma, were exposed to 2 M NaCl; however, no correlation with radiosensitivity was apparent. While a significant number of histone and non-histone proteins are present after extraction with 1.2 M NaCL, these proteins apparently have only a minor influence on radiosensitivity. However, if they are allowed to remain with DNA during electrophoresis, about 15 times more strand breaks are required to produce a similar amount of DNA migration in both DU145 and HT144 cells. These results suggest that the association between proteins and DNA within the nucleus, as probed by extraction with sodium chloride, does not help to explain differences in intrinsic radiosensitivity among cells of these diverse tumor cell lines. 33 refs., 11 figs

  7. Determination of neutral particle density and magnetic field direction from laser-induced Lyman-α fluorescence II - two-photon excitation

    International Nuclear Information System (INIS)

    Doppler-free two-photon excitation of Lyman-α fluorescence is investigated as a possible tool for measuring locally the neutral particle density and the magnetic field direction in a tokamak. It is shown that if sufficient laser powers are available, the desired information can, in a variety of cases, be inferred from the total intensity and from the polarisation of the fluorescence. Limitations arising from depolarising collisions are studied by generalising a previously developed theory for the collisional redistribution of light. An error analysis is performed to derive the expected experimental precision for various plasma conditions and laser energies. The conclusions of this analysis are similar to those of a previous study of one-photon excited fluorescence. They imply that with presently available laser energies the method would be restricted to the outer plasma regions, while application to the central regions would require further developments in laser technology. Various advantages and disadvantages of the two methods based on one-photon and two-photon excitation are discussed in detail

  8. Transverse energy and neutral pion spectra obtained from 16O- and 32S-induced reactions at 200 GeV/nucleon

    International Nuclear Information System (INIS)

    The main goal of the CERN heavy-ion experiments is the search for an indication that the predicted state of deconfined quarks and gluons, the quark-gluon plasma (QGP), has been produced. The most promising indication that this may, in fact, be the case comes from the NA38 dimuon measurements, which are focused on the question of J//psi/ suppression. This effect was predicted to be one of the signatures of QGP formation before any measurements were made, and it is the subject of the two other talks at this conference that deal with nucleus-nucleus reactions at ultrarelativistic energies. In this presentation we consider the general (global) features of heavy-ion reactions at CERN energies, and we examine the degree to which they differ from mere superpositions of nucleon-nucleon collisions. We discuss the present status of our data analysis and our main conclusions from the first round of CERN experiments with emphasis on transverse energy measurements, on attained energy densities, and on the spectra of produced neutral pions. Because of time limitations we will not discuss our measurements of distributions of charged particles and the analysis of these distributions in terms of fluctuations nor the results that we have obtained with the Plastic Ball on the behavior of target spectator matter. 20 refs., 5 figs

  9. Multimeric scaffolds displaying the HIV-1 envelope MPER induce MPER-specific antibodies and cross-neutralizing antibodies when co-immunized with gp160 DNA.

    Directory of Open Access Journals (Sweden)

    Shelly J Krebs

    Full Text Available Developing a vaccine that overcomes the diversity of HIV-1 is likely to require a strategy that directs antibody (Ab responses toward conserved regions of the viral Envelope (Env. However, the generation of neutralizing Abs (NAbs targeting these regions through vaccination has proven to be difficult. One conserved region of particular interest is the membrane proximal external region (MPER of Env located within the gp41 ectodomain. In order to direct the immune response to this region, the MPER and gp41 ectodomain were expressed separately as N-terminal fusions to the E2 protein of Geobacillus stearothermophilus. The E2 protein acts as a scaffold by self-assembling into 60-mer particles, displaying up to 60 copies of the fused target on the surface. Rabbits were immunized with E2 particles displaying MPER and/or the gp41 ectodomain in conjunction with DNA encoding full-length gp160. Only vaccines including E2 particles displaying MPER elicited MPER-specific Ab responses. NAbs were elicited after two immunizations that largely targeted the V3 loop. To overcome V3 immunodominance in the DNA component, E2 particles displaying MPER were used in conjunction with gp160 DNA lacking hypervariable regions V2, V3, or combined V1V2V3. All rabbits had HIV binding Ab responses and NAbs following the second vaccination. Using HIV-2/HIV-1 MPER chimeric viruses as targets, NAbs were detected in 12/16 rabbits after three immunizations. Low levels of NAbs specific for Tier 1 and 2 viruses were observed in all groups. This study provides evidence that co-immunizing E2 particles displaying MPER and gp160 DNA can focus Ab responses toward conserved regions of Env.

  10. Post-mating interactions and their effects on fitness of female and male Echinothrips americanus (Thysanoptera: Thripidae, a new insect pest in China.

    Directory of Open Access Journals (Sweden)

    Xiao-Wei Li

    Full Text Available Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furthermore, we tested the impact of mating and post-mating interactions on fitness parameters of males. Our results revealed that the re-mating frequency in female adults was extremely low during a 30-day period. However, post-mating interactions between females and males, consisting mainly of male harassment and female resistance, did occur and significantly reduced female longevity and fecundity. Interestingly, increased access to males did not affect the ratio of female offspring. For males, mating dramatically reduced their longevity. However, post-mating interactions with females had no effects on the longevity of mated males. These results enrich our basic knowledge about female and male mating and post-mating behaviors in this species and provide important information about factors that may influence population regulation of this important pest species.

  11. Post-mating interactions and their effects on fitness of female and male Echinothrips americanus (Thysanoptera: Thripidae), a new insect pest in China.

    Science.gov (United States)

    Li, Xiao-Wei; Jiang, Hong-Xue; Zhang, Xiao-Chen; Shelton, Anthony M; Feng, Ji-Nian

    2014-01-01

    Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furthermore, we tested the impact of mating and post-mating interactions on fitness parameters of males. Our results revealed that the re-mating frequency in female adults was extremely low during a 30-day period. However, post-mating interactions between females and males, consisting mainly of male harassment and female resistance, did occur and significantly reduced female longevity and fecundity. Interestingly, increased access to males did not affect the ratio of female offspring. For males, mating dramatically reduced their longevity. However, post-mating interactions with females had no effects on the longevity of mated males. These results enrich our basic knowledge about female and male mating and post-mating behaviors in this species and provide important information about factors that may influence population regulation of this important pest species. PMID:24489956

  12. Ultracold neutral plasmas.

    Science.gov (United States)

    Killian, Thomas C

    2007-05-01

    Ultracold neutral plasmas occupy an exotic regime of plasma physics in which electrons form a swarming, neutralizing background for ions that sluggishly move in a correlated manner. Strong interactions between the charged particles give rise to surprising dynamics such as oscillations of the average kinetic energy during equilibration and extremely fast recombination. Such phenomena offer stimulating and challenging problems for computational scientists, and the physics can be applied to other environments, such as the interior of gas giant planets and plasmas created by short-pulse laser irradiation of solid, liquid, and cluster targets. PMID:17478712

  13. Pichia pastoris-expressed dengue 2 envelope forms virus-like particles without pre-membrane protein and induces high titer neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Shailendra Mani

    Full Text Available Dengue is a mosquito-borne viral disease with a global prevalence. It is caused by four closely-related dengue viruses (DENVs 1-4. A dengue vaccine that can protect against all four viruses is an unmet public health need. Live attenuated vaccine development efforts have encountered unexpected interactions between the vaccine viruses, raising safety concerns. This has emphasized the need to explore non-replicating dengue vaccine options. Virus-like particles (VLPs which can elicit robust immunity in the absence of infection offer potential promise for the development of non-replicating dengue vaccine alternatives. We have used the methylotrophic yeast Pichia pastoris to develop DENV envelope (E protein-based VLPs. We designed a synthetic codon-optimized gene, encoding the N-terminal 395 amino acid residues of the DENV-2 E protein. It also included 5' pre-membrane-derived signal peptide-encoding sequences to ensure proper translational processing, and 3' 6× His tag-encoding sequences to facilitate purification of the expressed protein. This gene was integrated into the genome of P. pastoris host and expressed under the alcohol oxidase 1 promoter by methanol induction. Recombinant DENV-2 protein, which was present in the insoluble membrane fraction, was extracted and purified using Ni(2+-affinity chromatography under denaturing conditions. Amino terminal sequencing and detection of glycosylation indicated that DENV-2 E had undergone proper post-translational processing. Electron microscopy revealed the presence of discrete VLPs in the purified protein preparation after dialysis. The E protein present in these VLPs was recognized by two different conformation-sensitive monoclonal antibodies. Low doses of DENV-2 E VLPs formulated in alum were immunogenic in inbred and outbred mice eliciting virus neutralizing titers >1,1200 in flow cytometry based assays and protected AG129 mice against lethal challenge (p<0.05. The formation of immunogenic DENV-2 E

  14. Neutralization by Acetyl Salicylic Acid of the Testosterone induced Impaired Maspin Synthesis Stimulated by Estriol in Neutrophils through Nitric Oxide Synthesis

    OpenAIRE

    Manna, Emili; Bank, Sarbashri; Maiti, Smarajit; Jana, Pradipta; Sinha, Asru K.

    2015-01-01

    Purpose: Maspin, an anti breast cancer protein in the mammary cell and normal neutrophil has been reported to be synthesised by the stimulation of NO production induced by estriol. The role of testosterone was investigated in the synthesis of maspin in relation to that of estriol. Methods: Fifty normal female between the ages of 25-65 years old participated in the study. Maspin synthesis was demonstrated by in vitro translation of maspin mRNA, followed by the quantification of maspin by enzym...

  15. Nanogel-based pneumococcal surface protein A nasal vaccine induces microRNA-associated Th17 cell responses with neutralizing antibodies against Streptococcus pneumoniae in macaques.

    Science.gov (United States)

    Fukuyama, Y; Yuki, Y; Katakai, Y; Harada, N; Takahashi, H; Takeda, S; Mejima, M; Joo, S; Kurokawa, S; Sawada, S; Shibata, H; Park, E J; Fujihashi, K; Briles, D E; Yasutomi, Y; Tsukada, H; Akiyoshi, K; Kiyono, H

    2015-09-01

    We previously established a nanosized nasal vaccine delivery system by using a cationic cholesteryl group-bearing pullulan nanogel (cCHP nanogel), which is a universal protein-based antigen-delivery vehicle for adjuvant-free nasal vaccination. In the present study, we examined the central nervous system safety and efficacy of nasal vaccination with our developed cCHP nanogel containing pneumococcal surface protein A (PspA-nanogel) against pneumococcal infection in nonhuman primates. When [(18)F]-labeled PspA-nanogel was nasally administered to a rhesus macaque (Macaca mulatta), longer-term retention of PspA was noted in the nasal cavity when compared with administration of PspA alone. Of importance, no deposition of [(18)F]-PspA was seen in the olfactory bulbs or brain. Nasal PspA-nanogel vaccination effectively induced PspA-specific serum IgG with protective activity and mucosal secretory IgA (SIgA) Ab responses in cynomolgus macaques (Macaca fascicularis). Nasal PspA-nanogel-induced immune responses were mediated through T-helper (Th) 2 and Th17 cytokine responses concomitantly with marked increases in the levels of miR-181a and miR-326 in the serum and respiratory tract tissues, respectively, of the macaques. These results demonstrate that nasal PspA-nanogel vaccination is a safe and effective strategy for the development of a nasal vaccine for the prevention of pneumonia in humans. PMID:25669148

  16. ITER neutral beam system

    International Nuclear Information System (INIS)

    The Neutral Beam (NB) system for the International Thermonuclear Experimental Reactor (ITER) has reached a high degree of integration with the tokamak and with the rest of the plant. Operational requirements and maintainability have been considered in the design. The paper considers the integration with the tokamak, discusses design improvements which appear necessary and finally notes R and D progress in key areas. (author)

  17. CO2-Neutral Fuels

    Science.gov (United States)

    Goede, Adelbert; van de Sanden, Richard

    2016-06-01

    Mimicking the biogeochemical cycle of System Earth, synthetic hydrocarbon fuels are produced from recycled CO2 and H2O powered by renewable energy. Recapturing CO2 after use closes the carbon cycle, rendering the fuel cycle CO2 neutral. Non-equilibrium molecular CO2 vibrations are key to high energy efficiency.

  18. Issues in neutral currents

    International Nuclear Information System (INIS)

    The experimental results on low energy confirming the structure of the effective Lagrangian of the weak neutral current processes as predicted by the Salam-Weinberg model are reviewed. Some possible modifications of the effective Lagrangian and the feasibility of their experimental verification are also considered. (P.L.)

  19. Bleach Neutralizes Mold Allergens

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    Researchers at National Jewish Medical and Research Center have demonstrated that dilute bleach not only kills common household mold, but may also neutralize the mold allergens that cause most mold-related health complaints. The study, published in the Journal of Allergy and Clinical Immunology, is the first to test the effect on allergic…

  20. Mod en neutral seksualitet!

    DEFF Research Database (Denmark)

    Leer, Jonatan

    2013-01-01

    Towards a Neutral Sexuality! or Roland Barthes as a Queer Thinker? This article argues that the work of Roland Barthes has interesting perspectives in common with the queer theory. This argument will be put forward by using his concept of ‘the neutral’ that Barthes defines as “that which outplays...

  1. Whole-Chain Tick Saliva Proteins Presented on Hepatitis B Virus Capsid-Like Particles Induce High-Titered Antibodies with Neutralizing Potential.

    Directory of Open Access Journals (Sweden)

    Philipp Kolb

    Full Text Available Ticks are vectors for various, including pathogenic, microbes. Tick saliva contains multiple anti-host defense factors that enable ticks their bloodmeals yet also facilitate microbe transmission. Lyme disease-causing borreliae profit specifically from the broadly conserved tick histamine release factor (tHRF, and from cysteine-rich glycoproteins represented by Salp15 from Ixodes scapularis and Iric-1 from Ixodes ricinus ticks which they recruit to their outer surface protein C (OspC. Hence these tick proteins are attractive targets for anti-tick vaccines that simultaneously impair borrelia transmission. Main obstacles are the tick proteins´ immunosuppressive activities, and for Salp15 orthologs, the lack of efficient recombinant expression systems. Here, we exploited the immune-enhancing properties of hepatitis B virus core protein (HBc derived capsid-like particles (CLPs to generate, in E. coli, nanoparticulate vaccines presenting tHRF and, as surrogates for the barely soluble wild-type proteins, cysteine-free Salp15 and Iric-1 variants. The latter CLPs were exclusively accessible in the less sterically constrained SplitCore system. Mice immunized with tHRF CLPs mounted a strong anti-tHRF antibody response. CLPs presenting cysteine-free Salp15 and Iric-1 induced antibodies to wild-type, including glycosylated, Salp15 and Iric-1. The broadly distributed epitopes included the OspC interaction sites. In vitro, the anti-Salp15 antibodies interfered with OspC binding and enhanced human complement-mediated killing of Salp15 decorated borreliae. A mixture of all three CLPs induced high titered antibodies against all three targets, suggesting the feasibility of combination vaccines. These data warrant in vivo validation of the new candidate vaccines´ protective potential against tick infestation and Borrelia transmission.

  2. Two types of antibodies are induced by vaccination with A/California/2009 pdm virus: binding near the sialic acid-binding pocket and neutralizing both H1N1 and H5N1 viruses.

    Directory of Open Access Journals (Sweden)

    Nobuko Ohshima

    Full Text Available Many people have a history of catching the flu several times during childhood but no additional flu in adulthood, even without vaccination. We analyzed the total repertoire of antibodies (Abs against influenza A group 1 viruses induced in such a flu-resistant person after vaccination with 2009 H1N1 pandemic influenza virus. They were classified into two types, with no exceptions. The first type, the products of B cells newly induced through vaccination, binds near the sialic acid-binding pocket. The second type, the products of long-lived memory B cells established before vaccination, utilizes the 1-69 VH gene, binds to the stem of HA, and neutralizes both H1N1 and H5N1 viruses with few exceptions. These observations indicate that the sialic acid-binding pocket and its surrounding region are immunogenically very potent and majority of the B cells whose growth is newly induced by vaccination produce Abs that recognize these regions. However, they play a role in protection against influenza virus infection for a short period since variant viruses that have acquired resistance to these Abs become dominant. On the other hand, although the stem of HA is immunogenically not potent, the second type of B cells eventually becomes dominant. Thus, a selection system should function in forming the repertoire of long-lived memory B cells and the stability of the epitope would greatly affect the fate of the memory cells. Acquisition of the ability to produce Abs that bind to the stable epitope could be a major factor of flu resistance.

  3. Radiative lifetimes of neutral cerium

    International Nuclear Information System (INIS)

    Radiative lifetimes, accurate to ±5%, have been measured for 153 levels of neutral cerium using time-resolved laser-induced fluorescence (TRLIF) on a slow beam of cerium atoms. Of the 153 levels studied, 150 are even parity and 3 are odd parity. The levels range in energy from 16 869 to 28 557 cm-1. This set of Ce I lifetimes is much more extensive than others published to date, and will provide the absolute calibration for a very large set of measured Ce I transition probabilities. Accurate transition probabilities for lines in the visible and ultraviolet are needed both in astrophysics, for the determination of elemental abundances, and by the lighting community, for research and development of metal halide high-intensity discharge lamps.

  4. Radiative lifetimes of neutral erbium

    Energy Technology Data Exchange (ETDEWEB)

    Den Hartog, E A; Chisholm, J P; Lawler, J E, E-mail: eadenhar@wisc.ed, E-mail: chisholm@astro.wisc.ed, E-mail: jelawler@wisc.ed [Department of Physics, University of Wisconsin, 1150 University Ave., Madison, WI 53706 (United States)

    2010-08-14

    Radiative lifetimes have been measured for 123 levels of neutral erbium using time-resolved laser-induced fluorescence on a slow beam of erbium atoms. Of the 123 levels, 56 are even parity and range in energy from 26 993 to 40 440 cm{sup -1} and 67 are odd parity ranging from 16 070 to 38 401 cm{sup -1}. This set of Er i lifetimes is much more extensive than others published to date, with 90 of the 123 level lifetimes measured for the first time. These lifetimes will provide the absolute calibration for a large set of measured Er i transition probabilities. Spectroscopic studies of rare earth elements including erbium are motivated by research needs in both the astrophysics and lighting communities.

  5. Radiative lifetimes of neutral erbium

    International Nuclear Information System (INIS)

    Radiative lifetimes have been measured for 123 levels of neutral erbium using time-resolved laser-induced fluorescence on a slow beam of erbium atoms. Of the 123 levels, 56 are even parity and range in energy from 26 993 to 40 440 cm-1 and 67 are odd parity ranging from 16 070 to 38 401 cm-1. This set of Er i lifetimes is much more extensive than others published to date, with 90 of the 123 level lifetimes measured for the first time. These lifetimes will provide the absolute calibration for a large set of measured Er i transition probabilities. Spectroscopic studies of rare earth elements including erbium are motivated by research needs in both the astrophysics and lighting communities.

  6. Radiative lifetimes of neutral cerium

    Energy Technology Data Exchange (ETDEWEB)

    Den Hartog, E A; Buettner, K P; Lawler, J E [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States)], E-mail: eadenhar@wisc.edu, E-mail: Kevin.Buettner@usma.edu, E-mail: jelawler@wisc.edu

    2009-04-28

    Radiative lifetimes, accurate to {+-}5%, have been measured for 153 levels of neutral cerium using time-resolved laser-induced fluorescence (TRLIF) on a slow beam of cerium atoms. Of the 153 levels studied, 150 are even parity and 3 are odd parity. The levels range in energy from 16 869 to 28 557 cm{sup -1}. This set of Ce I lifetimes is much more extensive than others published to date, and will provide the absolute calibration for a very large set of measured Ce I transition probabilities. Accurate transition probabilities for lines in the visible and ultraviolet are needed both in astrophysics, for the determination of elemental abundances, and by the lighting community, for research and development of metal halide high-intensity discharge lamps.

  7. Flavour-changing neutral currents in models with extra ' boson

    Indian Academy of Sciences (India)

    S Sahoo; L Maharana

    2004-09-01

    New neutral gauge bosons ' are the features of many models addressing the physics beyond the standard model. Together with the existence of new neutral gauge bosons, models based on extended gauge groups (rank > 4) often predict new charged fermions also. A mixing of the known fermions with new states, with exotic weak-isospin assignments (left-handed singlets and right-handed doublets) will induce tree-level flavour-changing neutral interactions mediated by exchange, while if the mixing is only with new states with ordinary weak-isospin assignments, the flavour-changing neutral currents are mainly due to the exchange of the new neutral gauge boson '. We review flavour-changing neutral currents in models with extra ' boson. Then we discuss some flavour-changing processes forbidden in the standard model and new contributions to standard model processes.

  8. Neutral muonic helium(3)

    International Nuclear Information System (INIS)

    Neutral muonic helium, He++μ-e-, can be considered in two pieces. The (He++μ-)+-system is a hydrogenic ion halfway in size between an atom and a nucleus. It acts like a singly charged pseudo-nucleus to the electron surrounding it. The whole system appears like one hydrogen inside another. Neutral muonic helium can be formed in the ground state in which the coupling of the magnetic moments gives rise to a hyperfine structure (hfs). 3He++μ-e- has three spin one half particles interact without any restrictions by the Pauli exclusion principle. The level diagram of the ground state is shown. There is a large muonic hfs splitting corresponding to the He++μ- ion to be in one of the two spin states with total spin quantum number G = 0 and G = 1. To measure the atomic hfs superimposed on the G = 1 triplet state is the aim of this experiment. (Auth.)

  9. Ultracold Neutral Plasmas

    CERN Document Server

    Killian, T C; Pohl, T; Rost, J M

    2006-01-01

    Ultracold neutral plasmas, formed by photoionizing laser-cooled atoms near the ionization threshold, have electron temperatures in the 1-1000 kelvin range and ion temperatures from tens of millikelvin to a few kelvin. They represent a new frontier in the study of neutral plasmas, which traditionally deals with much hotter systems, but they also blur the boundaries of plasma, atomic, condensed matter, and low temperature physics. Modelling these plasmas challenges computational techniques and theories of non-equilibrium systems, so the field has attracted great interest from the theoretical and computational physics communities. By varying laser intensities and wavelengths it is possible to accurately set the initial plasma density and energy, and charged-particle-detection and optical diagnostics allow precise measurements for comparison with theoretical predictions. Recent experiments using optical probes demonstrated that ions in the plasma equilibrate in a strongly coupled fluid phase. Strongly coupled pla...

  10. Neutral beams for mirrors

    International Nuclear Information System (INIS)

    An important demonstration of negative ion technology is proposed for FY92 in the MFTF-α+T, an upgrade of the Mirror Fusion Test Facility at the Lawrence Livermore National Laboratory. This facility calls for 200-keV negative ions to form neutral beams that generate sloshing ions in the reactor end plugs. Three different beam lines are considered for this application. Their advantages and disadvantages are discussed

  11. Gargamelle: neutral current event

    CERN Multimedia

    1973-01-01

    This event shows real tracks of particles from the 1200 litre Gargamelle bubble chamber that ran on the PS from 1970 to 1976 and on the SPS from 1976 to 1979. In this image a neutrino passes close to a nucleon and reemerges as a neutrino. Such events are called neutral curent, as they are mediated by the Z0 boson which has no electric charge.

  12. Neutralization by Acetyl Salicylic Acid of the Testosterone induced Impaired Maspin Synthesis Stimulated by Estriol in Neutrophils through Nitric Oxide Synthesis

    Science.gov (United States)

    Manna, Emili; Bank, Sarbashri; Maiti, Smarajit; Jana, Pradipta; Sinha, Asru K.

    2015-01-01

    Purpose: Maspin, an anti breast cancer protein in the mammary cell and normal neutrophil has been reported to be synthesised by the stimulation of NO production induced by estriol. The role of testosterone was investigated in the synthesis of maspin in relation to that of estriol. Methods: Fifty normal female between the ages of 25-65 years old participated in the study. Maspin synthesis was demonstrated by in vitro translation of maspin mRNA, followed by the quantification of maspin by enzyme linked immune absorbent assay. NO was determined by methomoglobin method. Results: Incubation of the neutrophils in HBSS both with 30 nM estriol resulted in the synthesis of 1.8 ngm maspin with simultaneous increase of NO synthesis. In contrast incubating neutrophils with 20 nM testosterone in the presence of estriol inhibited maspin synthesis to 0.33 nM with simultaneous inhibition of NO synthesis from 1.89 nM to 0 nM at the same time. Addition of 0.2 μM flutamide, a testosterone receptor blocker to the incubation mixture restored the synthesis of maspin by 60.64 %. Incubation of 25 μM aspirin that stimulated NO synthesis restored the inhibition of maspin synthesis by testosterone by 79.1%. I-NAME, an inhibitor of nitric oxide synthase, abolished both maspin and NO synthesis. Scatchard plot of estriol binding in the presence of testosterone demonstrated that the male sex hormone inhibited the female sex hormone binding to its receptor by “cross talk” between the receptors. It was found that while 1.02 × 103 molecules of estriol bind each neutrophil at equilibrium, in the presence of testosterone (20 nM) in the binding mixture decreases the binding of estriol to 0.5 × 103 with little change in the dissociation constant compared to controls. Conclution: Estriol was found to stimulate maspin synthesis through the stimulation of NO, testosterone inhibited maspin synthesis through the inhibition of NO synthesis. PMID:26759534

  13. A truncated receptor-binding domain of MERS-CoV spike protein potently inhibits MERS-CoV infection and induces strong neutralizing antibody responses: implication for developing therapeutics and vaccines.

    Directory of Open Access Journals (Sweden)

    Lanying Du

    Full Text Available An emerging respiratory infectious disease with high mortality, Middle East respiratory syndrome (MERS, is caused by a novel coronavirus (MERS-CoV. It was first reported in 2012 in Saudi Arabia and has now spread to eight countries. Development of effective therapeutics and vaccines is crucial to save lives and halt the spread of MERS-CoV. Here, we show that a recombinant protein containing a 212-amino acid fragment (residues 377-588 in the truncated receptor-binding domain (RBD: residues 367-606 of MERS-CoV spike (S protein fused with human IgG Fc fragment (S377-588-Fc is highly expressed in the culture supernatant of transfected 293T cells. The purified S377-588-Fc protein efficiently binds to dipeptidyl peptidase 4 (DPP4, the receptor of MERS-CoV, and potently inhibited MERS-CoV infection, suggesting its potential to be further developed as a therapeutic modality for treating MERS-CoV infection and saving the patients' lives. The recombinant S377-588-Fc is able to induce in the vaccinated mice strong MERS-CoV S-specific antibodies, which blocks the binding of RBD to DPP4 receptor and effectively neutralizes MERS-CoV infection. These findings indicate that this truncated RBD protein shows promise for further development as an effective and safe vaccine for the prevention of MERS-CoV infection.

  14. Investigation of the neutral loss of a full amino acid mass during collision-induced dissociation of the b(3)+ ion derived from a model peptide containing a 4-aminobutyric acid residue.

    Science.gov (United States)

    Talaty, Erach R; Chueachavalit, Chawalee; Osburn, Sandra; Van Stipdonk, Michael J

    2007-01-01

    In a previous study we found that a dominant fragmentation pathway observed for collision-induced dissociation (CID) of b(3)+ derived from peptides with sequence AXAG, where X is gamma-aminobutyric acid (gammaAbu) or epsilon-aminocaproic acid (Cap), involved the loss of 89 mass units (u). A neutral loss of 89 u corresponded to the free acid mass of an alanine (A) residue. This specific pathway was studied in greater detail here using a series of A(gammaAbu)AG peptides with strategic positioning of (15)N, (13)C and (2)H isotope labels. Based on the extensive labeling, several possible routes to the net elimination of 89 u are proposed. One is based on initial elimination of either aziridinone or imine and CO, followed by opening of an oxazolinone, tautomerization and elimination of H2O. Another involves formation of an aziridinone by cleavage of the N-terminal amide bond, and transfer of O and H atoms to this fragment via an H-bonded ion-molecule complex to complete the loss of 89 u. Both types of pathway include the transfer/migration of H atoms from the alpha-carbon position of gammaAbu or A residues. PMID:17610213

  15. Calicobenedenia Polyprioni n. gen., n. sp. (Monogenoidea: Capsalidae) from the external surfaces of wreckfish, Polyprion americanus (Teleostei: Polyprionidae), in the north Atlantic.

    Science.gov (United States)

    Kritsky, D C; Fennessy, C J

    1999-04-01

    Calicobenedenia polyprioni n. sp. (Capsalidae) is described from the external surfaces (skin and eye) of wreckfish, Polyprion americanus (Teleostei, Perciformes, Polyprionidae), from the north Atlantic Ocean. The monotypic Calicobenedenia n. gen. is proposed for this species and is characterized, in part, by its members possessing an aseptate haptor armed with 14 submarginal hooks and 1 pair of anchors, a common genital pore opening marginally immediately posterior to the left cephalic lobe, 2 testes juxtaposed near the body midlength, and by lacking cephalic suckers or adhesive discs, accessory haptoral sclerites, and a uterine valve. The new genus most closely resembles Entobdella, which differs from Calicobenedenia by having an aseptate haptor armed with 14 submarginal hooks, 2 pairs of anchors, and a pair of accessary sclerites. PMID:10219294

  16. A comparison of human chorionic gonadotropin and luteinizing hormone releasing hormone on the induction of spermiation and amplexus in the American toad (Anaxyrus americanus

    Directory of Open Access Journals (Sweden)

    Kouba Andrew J

    2012-08-01

    Full Text Available Abstract Background Captive breeding programs for endangered amphibian species often utilize exogenous hormones for species that are difficult to breed. The purpose of our study was to compare the efficacy of two different hormones at various concentrations on sperm production, quantity and quality over time in order to optimize assisted breeding. Methods Male American toads (Anaxyrus americanus were divided into three separate treatment groups, with animals in each group rotated through different concentrations of luteinizing hormone releasing hormone analog (LHRH; 0.1, 1.0, 4.0 and 32 micrograms/toad, human chorionic gonadotropin (hCG; 50, 100, 200, and 300 IU, or the control over 24 hours. We evaluated the number of males that respond by producing spermic urine, the sperm concentration, percent motility, and quality of forward progression. We also evaluated the effects of hCG and LHRH on reproductive behavior as assessed by amplexus. Data were analyzed using the Generalized Estimating Equations incorporating repeated measures over time and including the main effects of treatment and time, and the treatment by time interaction. Results The hormone hCG was significantly more effective at stimulating spermiation in male Anaxyrus americanus than LHRH and showed a dose-dependent response in the number of animals producing sperm. At the most effective hCG dose (300 IU, 100% of the male toads produced sperm, compared to only 35% for the best LHRH dose tested (4.0 micrograms. In addition to having a greater number of responders (P  Conclusion There is a clear dichotomy between the two hormones’ physiological responses on gamete production and stimulation of amplexus. Understanding how these two hormones influence physiology and reproductive behaviors in amphibians will have direct bearing on establishing similar breeding protocols for endangered species.

  17. Sequence conservation in the Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) from hookworm infected individuals in Thailand.

    Science.gov (United States)

    Ungcharoensuk, Charoenchai; Putaporntip, Chaturong; Pattanawong, Urassaya; Jongwutiwes, Somchai

    2012-12-01

    The Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) was one of the promising vaccine candidates against the most prevalent human hookworm species as adverse vaccine reaction has compromised further human vaccine trials. To elucidate the gene structure and the extent of sequence diversity, we determined the complete nucleotide sequence of the Na-asp-2 gene of individual larvae from 32 infected subjects living in 3 different endemic areas of Thailand. Sequence analysis revealed that the gene encoding Na-ASP-2 comprised 8 exons. Of 3 nucleotide substitutions in these exons, only one causes an amino acid change from leucine to methionine. A consensus conserved GT and AG at the 5' and the 3' boundaries of each intron was observed akin to those found in other eukaryotic genes. Introns of Na-asp-2 contained 23 nucleotide substitutions and 0-18 indels. The mean number of nucleotide substitutions per site (d) in introns was not significantly different from the mean number of synonymous substitutions per synonymous site (d(S)) in exons whereas d in introns was significantly exceeded d(N) (the mean number of nonsynonymous substitutions per nonsynonymous site) in exons (pOnchocerca volvulus, Heterodera glycines, Caenorhabditis elegans and human were relatively conserved, suggesting evolutionary conservation of these genes. Sequence conservation in Na-ASP-2 may not compromise further vaccine design if adverse vaccine effects could be resolved whereas microheterogeneity in introns of this locus may be useful for population genetics analysis of N. americanus. PMID:22964044

  18. Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    Energy Technology Data Exchange (ETDEWEB)

    Asojo, Oluwatoyin A., E-mail: oasojo@unmc.edu [Eppley Institute for Research in Cancer and Allied Diseases, 987696 Nebraska Medical Center, Omaha, NE 68198-7696 (United States); Loukas, Alex [Department of Microbiology and Tropical Medicine, The George Washington University Medical Center, Washington DC 20037 (United States); Division of Infectious Diseases and Immunology, Queensland Institute of Medical Research, Brisbane, QLD 4006 (Australia); Inan, Mehmet; Barent, Rick; Huang, Jicai; Plantz, Brad; Swanson, Amber; Gouthro, Mark; Meagher, Michael M. [Department of Chemical Engineering, The University of Nebraska-Lincoln, Lincoln, NE 68588-0643 (United States); Hotez, Peter J. [Department of Microbiology and Tropical Medicine, The George Washington University Medical Center, Washington DC 20037 (United States); Eppley Institute for Research in Cancer and Allied Diseases, 987696 Nebraska Medical Center, Omaha, NE 68198-7696 (United States)

    2005-04-01

    In order to clarify the structural basis of the pathogenesis-related-1 domain, Na-ASP-1, the first multi-domain ASP from the human hookworm parasite N. americanus, has been crystallized. 2.2 Å resolution data have been collected from a crystal belonging to the monoclinic space group P2{sub 1}. Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 Å have been collected from a crystal that belongs to the monoclinic space group P2{sub 1} with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit.

  19. Electro-Optical Nanotraps for Neutral Atoms

    OpenAIRE

    Murphy, Brian; Hau, Lene Vestergaard

    2008-01-01

    We propose a new class of nanoscale electro-optical traps for neutral atoms. A prototype is the toroidal trap created by a suspended, charged carbon nanotube decorated with a silver nanosphere dimer. An illuminating laser field, blue detuned from an atomic resonance frequency, is strongly focused by plasmons induced in the dimer and generates both a repulsive potential barrier near the nanostructure surface and a large viscous damping force that facilitates trap loading. Atoms with velocities...

  20. Nonexotic Neutral Gauge Bosons

    OpenAIRE

    Appelquist, Thomas; Dobrescu, Bogdan A.; Hopper, Adam R.

    2002-01-01

    We study theoretical and experimental constraints on electroweak theories including a new color-singlet and electrically-neutral gauge boson. We first note that the electric charges of the observed fermions imply that any such Z' boson may be described by a gauge theory in which the Abelian gauge groups are the usual hypercharge along with another U(1) component in a kinetic-diagonal basis. Assuming that the observed quarks and leptons have generation-independent U(1) charges, and that no new...

  1. Atmospheric Measurements of Neutral Nucleating Clusters (Invited)

    Science.gov (United States)

    Zhao, J.; Eisele, F. L.; Smith, J. N.; Chen, M.; Jiang, J.; Kuang, C.; McMurry, P. H.

    2010-12-01

    Nanoparticles produced by nucleation can subsequently grow to cloud condensation nuclei (CCN) within one or two days and hence affect cloud formation, precipitation, and atmospheric radiation budgets. As an intermediate stage between molecules and nanoparticles, neutral molecular clusters are believed to play an important role in processes that lead to boundary layer nucleation. Therefore, knowledge of chemical composition, concentrations, thermodynamic properties, and evolution of neutral molecular clusters is essential to better elucidate the nucleation mechanism and to reduce the uncertainty in nucleation rates used in global climate models. Here we present laboratory and field measurements from a recently developed chemical ionization mass spectrometer (the Cluster-CIMS) designed to measure atmospheric neutral clusters (Zhao et al., 2010). The sensitivity of the Cluster-CIMS was significantly improved by using a unique conical octopole device in the first vacuum stage for transmitting and focusing ions, which was further confirmed by ion trajectory simulations using SIMION. The ion cluster formation in the atmospheric-pressure inlet was controlled by two processes: neutral ionization and ion-induced clustering (IIC), which can be differentiated from the time independency of the intensity ratio between the cluster and monomer ions. Two methods were employed to separate neutral clusters from the ion-induced clustering. The concentrations and distribution of the neutral nucleating clusters containing up to 4 H2SO4 are estimated from the above methods at three measurement sites in the US (NCAR foothill laboratory, Manitou Forest Observatory, and Atlanta). Typically, the molecular cluster concentrations are well correlated with the concentrations of nanoparticles measured simultaneously during the nucleation event periods. The Cluster-CIMS was employed to measure clusters containing both sulfuric acid and amines in summer 2010 at NCAR foothill laboratory

  2. Comparison of Search Engines Non-Neutral and Neutral Behaviors

    OpenAIRE

    COUCHENEY, Pierre; Maillé, Patrick; Tuffin, Bruno

    2012-01-01

    Network neutrality has recently attracted a lot of attention but search neutrality is also becoming a vivid subject of discussion because a non-neutral search may prevent some relevant content from being accessed by users. We propose in this paper to model two situations of a non-neutral search engine behavior, which can rank the link propositions according to the pro t a search can generate for it instead of just relevance: the case when the search engine owns some content, and the case when...

  3. Antihypertensive neutral lipid

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, F.L.; Blank, M.L.

    1986-06-17

    A method is described for treating a warm-blooded animal comprising administering to the animal a neutral glycerolipid with a 12 to 20 carbon alkyl group at the sn-1 position, a short carbon chain acyl group at the sn-2 position and a hydroxyl group at the sn-3 position in an amount sufficient to lower the arterial blood pressure of the animal. A method is also described for treating a warm-blooded animal comprising administering a composition consisting essentially of a 1-alkyl-2-acetyl (or propionyl)-sn glycerol in combination with a 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine, wherein the 1-alkyl groups contain 12 to 20 carbon atoms, dissolved in an inert pharmaceutically acceptable solvent in amounts sufficient to lower the arterial blood pressure of the animal.

  4. Toxicities of Five Types of Insecticide to Adults of Invasive Thrips Echinothrips americanus Morgan in China%5种杀虫剂对入侵我国美洲棘蓟马成虫室内毒力测定

    Institute of Scientific and Technical Information of China (English)

    朱亮; 宫亚军; 石宝才; 王泽华; 康总江; 魏书军

    2011-01-01

    [Aims] The invasive thrips Echinothrips americanus Morgan was recently reported in China, which causes damage to many greenhouse crops. The toxicities of five types of insecticide to adults of E. Americanus were determined using residue-on-glass exposure technique. [Results] The results showed that the order of toxicity to Echinothrips americanus Morgan adults from low to high is: chlorpyrifos, acetamiprid, abamectin, beta cypermethrin and spinosad. [Conclusions] In the controlling of this pest, chlorpyrifos should be avoided, the biogenic pesticides spinosad are recommended and alternate use of pyrethroid and nicotine pesticides should be adopted.%[目的]美洲棘蓟马Echinothrips americanus Morgan是国内新报道的外来种类,可对多种温室作物造成危害.采用玻璃残留处理法测定了5种杀虫剂对美洲棘蓟马成虫的毒力.[结果]5种杀虫剂对美洲棘蓟马成虫的毒力排序为毒死蜱<啶虫脒<阿维菌素<高效氯氰菊酯<多杀霉素.[结论]在防治中应避免使用毒死蜱等对该虫毒性较低的杀虫剂进行防治,尽量选用毒性较高的生物源类杀虫剂多杀霉素,交替使用菊酯类和烟碱类农药.

  5. CO2-neutral fuels

    Science.gov (United States)

    Goede, A. P. H.

    2015-08-01

    The need for storage of renewable energy (RE) generated by photovoltaic, concentrated solar and wind arises from the fact that supply and demand are ill-matched both geographically and temporarily. This already causes problems of overcapacity and grid congestion in countries where the fraction of RE exceeds the 20% level. A system approach is needed, which focusses not only on the energy source, but includes conversion, storage, transport, distribution, use and, last but not least, the recycling of waste. Furthermore, there is a need for more flexibility in the energy system, rather than relying on electrification, integration with other energy systems, for example the gas network, would yield a system less vulnerable to failure and better adapted to requirements. For example, long-term large-scale storage of electrical energy is limited by capacity, yet needed to cover weekly to seasonal demand. This limitation can be overcome by coupling the electricity net to the gas system, considering the fact that the Dutch gas network alone has a storage capacity of 552 TWh, sufficient to cover the entire EU energy demand for over a month. This lecture explores energy storage in chemicals bonds. The focus is on chemicals other than hydrogen, taking advantage of the higher volumetric energy density of hydrocarbons, in this case methane, which has an approximate 3.5 times higher volumetric energy density. More importantly, it allows the ready use of existing gas infrastructure for energy storage, transport and distribution. Intermittent wind electricity generated is converted into synthetic methane, the Power to Gas (P2G) scheme, by splitting feedstock CO2 and H2O into synthesis gas, a mixture of CO and H2. Syngas plays a central role in the synthesis of a range of hydrocarbon products, including methane, diesel and dimethyl ether. The splitting is accomplished by innovative means; plasmolysis and high-temperature solid oxygen electrolysis. A CO2-neutral fuel cycle is

  6. CO2-neutral fuels

    Directory of Open Access Journals (Sweden)

    Goede A. P. H.

    2015-01-01

    Full Text Available The need for storage of renewable energy (RE generated by photovoltaic, concentrated solar and wind arises from the fact that supply and demand are ill-matched both geographically and temporarily. This already causes problems of overcapacity and grid congestion in countries where the fraction of RE exceeds the 20% level. A system approach is needed, which focusses not only on the energy source, but includes conversion, storage, transport, distribution, use and, last but not least, the recycling of waste. Furthermore, there is a need for more flexibility in the energy system, rather than relying on electrification, integration with other energy systems, for example the gas network, would yield a system less vulnerable to failure and better adapted to requirements. For example, long-term large-scale storage of electrical energy is limited by capacity, yet needed to cover weekly to seasonal demand. This limitation can be overcome by coupling the electricity net to the gas system, considering the fact that the Dutch gas network alone has a storage capacity of 552 TWh, sufficient to cover the entire EU energy demand for over a month. This lecture explores energy storage in chemicals bonds. The focus is on chemicals other than hydrogen, taking advantage of the higher volumetric energy density of hydrocarbons, in this case methane, which has an approximate 3.5 times higher volumetric energy density. More importantly, it allows the ready use of existing gas infrastructure for energy storage, transport and distribution. Intermittent wind electricity generated is converted into synthetic methane, the Power to Gas (P2G scheme, by splitting feedstock CO2 and H2O into synthesis gas, a mixture of CO and H2. Syngas plays a central role in the synthesis of a range of hydrocarbon products, including methane, diesel and dimethyl ether. The splitting is accomplished by innovative means; plasmolysis and high-temperature solid oxygen electrolysis. A CO2-neutral fuel

  7. The merits of neutral theory

    NARCIS (Netherlands)

    Alonso, David; Etienne, Rampal S.; McKane, Alan J.

    2006-01-01

    Hubbell's neutral theory of biodiversity has challenged the classic niche-based view of ecological community structure. Although there have been many attempts to falsify Hubbell's theory, we argue that falsification should not lead to rejection, because there is more to the theory than neutrality al

  8. Self-neutralizing well acidizing

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, E.A.; Scheuerman, R.F.

    1974-07-30

    A process for acidizing a subterranean region by contacting it with an acidic solution is improved by dissolving in the solution a pH-increasing reactant that subsequently adjusts the pH of the solution to a selected relatively neutral value. Urea is an example of the acid neutralizer. (10 claims)

  9. HIV-1 binding and neutralizing antibodies of injecting drug users

    Directory of Open Access Journals (Sweden)

    E.P. Ouverney

    2005-09-01

    Full Text Available Previous studies have demonstrated a stronger seroreactivity against some synthetic peptides responsible for inducing neutralizing antibodies in injecting drug users (IDU compared to that of individuals sexually infected with HIV-1 (S, but the effectiveness in terms of the neutralizing ability of these antibodies has not been evaluated. Our objective was to study the humoral immune response of IDU by determining the specificity of their antibodies and the presence of neutralizing antibodies. The neutralization capacity against the HIV-1 isolate MN (genotype B, the primary HIV-1 isolate 95BRRJ021 (genotype F, and the seroreactivity with peptides known to induce neutralizing antibodies, from the V2 and V3 loops of different HIV-1 subtypes, were analyzed. Seroreactivity indicates that IDU plasma are more likely to recognize a broader range of peptides than S plasma, with significantly higher titers, especially of V3 peptides. Similar neutralization frequencies of the MN isolate were observed in plasma of the IDU (16/47 and S (20/60 groups in the 1:10 dilution. The neutralization of the 95BRRJ021 isolate was more frequently observed for plasma from the S group (15/23 than from the IDU group (15/47, P = 0.0108. No correlation between neutralization and seroreactivity with the peptides tested was observed. These results suggest that an important factor responsible for the extensive and broad humoral immune response observed in IDU is their infection route. There was very little difference in neutralizing antibody response between the IDU and S groups despite their differences in seroreactivity and health status.

  10. Population parameters and the relationships between environmental factors and abundance of the Acetes americanus shrimp (Dendrobranchiata: Sergestidae near a coastal upwelling region of Brazil

    Directory of Open Access Journals (Sweden)

    Ana Paula Freitas dos Santos

    2015-09-01

    Full Text Available AbstractThe population dynamics of Acetes americanus was investigated, focusing on the sex ratio, individual growth, longevity, recruitment and relationship between abundance and environmental factors in the region of Macaé, strongly influenced by coastal upwelling. Otter trawl net samplings were performed from July 2010 to June 2011 at two points (5 m and 15 m. Nearly 19,500 specimens, predominantly females (77.15%, were captured. Their sizes, larger than that of males, indicated sexual dimorphism. Shrimps at lower latitudes present larger sizes and longer longevity than those from higher latitudes. This difference is probably due to low temperatures and high primary productivity. Though no statistical correlation was found between abundance and environmental factors, the species was more abundant in temperatures closer to 20.0º C and in months with high chlorophyll-a levels. Due to the peculiar characteristics of this region, A. americanusshowed greater differences in size and longevity than individuals sampled in other studies undertaken in the continental shelf of Southeast Brazil.

  11. Two crystal forms of a helix-rich fatty acid- and retinol-binding protein, Na-FAR-1, from the parasitic nematode Necator americanus

    International Nuclear Information System (INIS)

    Na-FAR-1, a fatty acid- and retinol-binding protein, was expressed in bacteria, purified and crystallized. Crystals grew in two different morphologies under the same conditions. Na-FAR-1 is an unusual α-helix-rich fatty acid- and retinol-binding protein from Necator americanus, a blood-feeding intestinal parasitic nematode of humans. It belongs to the FAR protein family, which is unique to nematodes; no structural information is available to date for FAR proteins from parasites. Crystals were obtained with two different morphologies that corresponded to different space groups. Crystal form 1 exhibited space group P432 (unit-cell parameters a = b = c = 120.80 Å, α = β = γ = 90°) and diffracted to 2.5 Å resolution, whereas crystal form 2 exhibited space group F23 (unit-cell parameters a = b = c = 240.38 Å, α = β = γ = 90°) and diffracted to 3.2 Å resolution. Crystal form 2 showed signs of significant twinning

  12. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

    Science.gov (United States)

    Cronin, Matthew A; Rincon, Gonzalo; Meredith, Robert W; MacNeil, Michael D; Islas-Trejo, Alma; Cánovas, Angela; Medrano, Juan F

    2014-01-01

    We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears. PMID:24477675

  13. Bacterial communities associated with lesions of two forms of shell disease in the American lobster (Homarus americanus, Milne Edwards) from Atlantic Canada.

    Science.gov (United States)

    Quinn, Robert A; Cawthorn, Richard J; Summerfield, Rachael L; Smolowitz, Roxanna; Chistoserdov, Andrei Y

    2013-06-01

    Shell disease is a major threat to the American lobster (Homarus americanus, Milne Edwards) fishery. Here we describe the composition of microbial communities associated with lesions of 2 forms of shell disease in Atlantic Canada, (i) a trauma shell disease (TSD) characterized by massive lesions and (ii) an enzootic shell disease (EnSD) characterized by irregularly shaped lesions with a distinct orange to yellow color. The microbiology of the lesions was described by polymerase chain reaction and denaturing gradient gel electrophoresis of 16S rDNA amplified from scrapings of the shell lesions and was compared with communities of unaffected carapaces and previously described forms of shell diseases. Both TSD and EnSD lesions were dominated by members of Alphaproteobacteria, Gammaproteobacteria, and Flavobacteria, all commonly detected in other forms of shell disease; however, unique members of Epsilonproteobacteria were also present. Two Vibrio spp. and 2 Pseudoalteromonas spp. were dominant in lesions of TSD and a Tenacibaculum sp. and Tenacibaculum ovolyticum were dominant in lesions of EnSD. The TSD and EnSD in this study contained similar taxa as other shell disease forms; however, their microbiology is mostly different and neither resembles that of epizootic shell disease. PMID:23750952

  14. Incidence of Infestation and Larval Success of Emerald Ash Borer (Agrilus planipennis) on White Fringetree (Chionanthus virginicus), Chinese Fringetree (Chionanthus retusus), and Devilwood (Osmanthus americanus).

    Science.gov (United States)

    Cipollini, Don; Rigsby, Chad M

    2015-10-01

    We compared the incidence of infestation by emerald ash borer (EAB) and lilac borer on white fringetree to that of its Asian congener, Chinese fringetree, Chionanthus retusus, and a North American relative, devilwood, Osmanthus americanus. We also conducted laboratory bioassays to determine the suitability of these hosts for EAB larvae. At Spring Grove Cemetery and Arboretum in Cincinnati, Ohio, 9 of 28 white fringetrees examined were infested by EAB. Most of the white fringetrees had lilac borer infestation, and most of the trees infested by EAB also had lilac borer infestation. None of the 11 Chinese fringetrees examined were infested by either EAB or lilac borer. Each of the five devilwood individuals examined was infested by lilac borer, but not EAB. At The Morton Arboretum in Lisle, Illinois, 7 of 16 white fringetrees examined were infested by EAB, while none of the seven Chinese fringetrees examined were infested by either insect. A 40-d bioassay confirmed that white fringetree was an acceptable host, producing fourth-instar larvae that were smaller than those produced on a highly susceptible cultivar of green ash, Fraxinus pennsylvanica. No larvae survived on Chinese fringetree, and neonates were largely incapable of feeding on it. Two larvae survived on devilwood, reaching the second instar and excavating extensive galleries. Future work should be aimed at biotic and abiotic factors influencing the susceptibility of white fringetree, as well as further examination of close relatives for their vulnerability to EAB. PMID:26314014

  15. 美洲棘蓟马对不同蔬菜寄主的偏好性%Hosts preference of Echinothrips americanus Morgan for different vegetables

    Institute of Scientific and Technical Information of China (English)

    朱亮; 石宝才; 宫亚军; 王泽华; 康总江; 马吉德; 魏书军

    2013-01-01

    Echinothrips americanus Morgan (Thysanoptera; Thripidae) was recently (2010) found in the Beijing area and Yangling, Shaanxi Province, China. Current studies report that this thrips uses 48 families-106 species-as host plants, most of which are ornamental plants in the Araceae, Euphorbiaceae, and Apocynaceae families. The host preferences of this thrips among vegetable plants have rarely been studied. The preference for and suitability of 13 potential crop hosts of E. americanus were studied in the laboratory by comparing adult host selection, oviposition preference, and developmental and survival rates. Twelve vegetable species, i. e., Vigna unguiculata, Glycine max (Leguminosae), Daucus carota, Foeniculum vulgare (Apiaceae), Solarium melongena, Capsicum frutescens, Solarium lycopersicum (Solanaceae), Cucumis sativus, Cucurbita moschata (Cucurbitaceae), Brassica chinensis, Brassica campestris, and Brassica oleracea (Brassicaceae), and one non-vegetable host, Medicago sativa (Fabaceae) were tested. One to two weeks-old plants of each crop were grown in a greenhouse into which 100 thrips were released, and plants were examined for thrips infestation daily. The host-plant and oviposition selection data were analyzed with a log-linear model and variance analysis using the software DPS vl3.5. The host and oviposition preference of the thrips to the 13 different plant species differed significantly. The most adults were found on C. moschata, with 23.5 per plant, while the plant with the most eggs was C. frutescens, with 50. 32 per plant. No adults were found on F. vulgare, B. oleracea, or M. sativa. There were significantly more adults on C. sativus, C. moschata, B. chinensis, G. max, and C. frutescens, more than 10 per plant, than on the other host plants. Additionally, there were significantly more eggs on those five host species-more than 30 per plant-than on other plants, except V. unguiculata. There were no eggs on D. carota, B. oleracea, or M. sativa, suggesting

  16. The Myth of Neutral Taxation

    OpenAIRE

    Murray N. Rothbard

    1981-01-01

    Economists have long believed that government’s tax and expendi- ture policy either is, or can readily be made to be, neutral to the market. Free-market economists have advocated such neutrality of government, and even economists favoring redistributive actions by government have believed that the service activities and the re- distributive activities of government can easily be distinguished, at least in concept. The purpose of this paper is to examine the nature and implications of fiscal...

  17. The Economics of Net Neutrality

    OpenAIRE

    Hahn, Robert W.; Wallsten, Scott

    2006-01-01

    This essay examines the economics of "net neutrality" and broadband Internet access. We argue that mandating net neutrality would be likely to reduce economic welfare. Instead, the government should focus on creating competition in the broadband market by liberalizing more spectrum and reducing entry barriers created by certain local regulations. In cases where a broadband provider can exercise market power the government should use its antitrust enforcement authority to police anticompetitiv...

  18. Neutral theory in community ecology

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    One of the central goals of community ecology is to understand the forces that maintain species diversity within communities. The traditional niche-assembly theory asserts that species live together in a community only when they differ from one another in resource uses. But this theory has some difficulties in explaining the diversity often observed in specie-rich communities such as tropical forests. As an alternative to the niche theory, Hubbell and other ecologists introduced a neutral model. Hubbell argues that the number of species in a community is controlled by species extinction and immigration or speciation of new species. Assuming that all individuals of all species in a trophically similar com-munity are ecologically equivalent, Hubbell's neutral theory predicts two important statistical distributions. One is the asymptotic log-series distribution for the metacommunities under point mutation speciation, and the other is the zero-sum multinomial distribution for both local communities under dispersal limitation and metacommunities under random fission speciation. Unlike the niche-assembly theory, the neutral theory takes similarity in species and individuals as a starting point for investigating species diversity. Based on the fundamental processes of birth, death, dispersal and spe-ciation, the neutral theory provided the first mechanistic explanation of species abundance distribution commonly observed in natural communities. Since the publication of the neutral theory, there has been much discussion about it, pro and con. In this paper, we summarize recent progress in the assumption, prediction and speciation mode of the neutral theory, including progress in the theory itself, tests about the assumption of the theory, prediction and speciation mode at the metacommunity level. We also suggest that the most important task in the future is to bridge the niche-assembly theory and the neutral theory, and to add species differences to the neutral theory and

  19. Vendor neutral archive in PACS

    Directory of Open Access Journals (Sweden)

    Tapesh Kumar Agarwal

    2012-01-01

    Full Text Available An archive is a location containing a collection of records, documents, or other materials of historical importance. An integral part of Picture Archiving and Communication System (PACS is archiving. When a hospital needs to migrate a PACS vendor, the complete earlier data need to be migrated in the format of the newly procured PACS. It is both time and money consuming. To address this issue, the new concept of vendor neutral archive (VNA has emerged. A VNA simply decouples the PACS and workstations at the archival layer. This is achieved by developing an application engine that receives, integrates, and transmits the data using the different syntax of a Digital Imaging and Communication in Medicine (DICOM format. Transferring the data belonging to the old PACS to a new one is performed by a process called migration of data. In VNA, a number of different data migration techniques are available to facilitate transfer from the old PACS to the new one, the choice depending on the speed of migration and the importance of data. The techniques include simple DICOM migration, prefetch-based DICOM migration, medium migration, and the expensive non-DICOM migration. "Vendor neutral" may not be a suitable term, and "architecture neutral," "PACS neutral," "content neutral," or "third-party neutral" are probably better and preferred terms. Notwithstanding this, the VNA acronym has come to stay in both the medical IT user terminology and in vendor nomenclature, and radiologists need to be aware of its impact in PACS across the globe.

  20. TNF-alpha neutralizing antibody blocks thermal sensitivity induced by compound 48/80-provoked mast cell degranulation [v1; ref status: indexed, http://f1000r.es/1mq

    Directory of Open Access Journals (Sweden)

    Devavani Chatterjea

    2013-08-01

    Full Text Available Background:  Neuro-inflammatory circuits in the tissue regulate the complex pathophysiology of pain.  Protective nociceptive pain serves as an early warning system against noxious environmental stimuli.  Tissue-resident mast cells orchestrate the increased thermal sensitivity following injection of basic secretagogue compound 48/80 in the hind paw tissues of ND4 mice.  Here we investigated the effects of pre-treatment with TNF-α neutralizing antibody on compound 48/80-provoked thermal hyperalgesia.  Methods:  We treated ND4 Swiss male mice with intravenous anti-TNF-α antibody or vehicle 30 minutes prior to bilateral, intra-plantar compound 48/80 administration and measured changes in the timing of hind paw withdrawal observed subsequent to mice being placed on a 51oC hotplate.  We also assessed changes in tissue swelling, TNF-α gene expression and protein abundance, mast cell degranulation, and neutrophil influx in the hind paw tissue.  Findings:  We found that TNF-α neutralization significantly blocked thermal hyperalgesia, and reduced early tissue swelling. TNF-α neutralization had no significant effect on mast cell degranulation or neutrophil influx into the tissue, however.  Moreover, no changes in TNF-α protein or mRNA levels were detected within 3 hours of administration of compound 48/80.  Interpretation:  The neutralizing antibodies likely target pre-formed TNF-α including that stored in the granules of tissue-resident mast cells. Pre-formed TNF-α, released upon degranulation, has immediate effects on nociceptive signaling prior to the induction of neutrophil influx.  These direct effects on nociceptors are abrogated by TNF-α blockade resulting in compromised nociceptive withdrawal responses to acute, harmful environmental stimuli.

  1. TNF-alpha neutralizing antibody blocks thermal sensitivity induced by compound 48/80-provoked mast cell degranulation [v2; ref status: indexed, http://f1000r.es/1w5

    Directory of Open Access Journals (Sweden)

    Devavani Chatterjea

    2013-09-01

    Full Text Available Background: Neuro-inflammatory circuits in the tissue regulate the complex pathophysiology of pain. Protective nociceptive pain serves as an early warning system against noxious environmental stimuli. Tissue-resident mast cells orchestrate the increased thermal sensitivity following injection of basic secretagogue compound 48/80 in the hind paw tissues of ND4 mice. Here we investigated the effects of pre-treatment with TNF-α neutralizing antibody on compound 48/80-provoked thermal hyperalgesia. Methods: We treated ND4 Swiss male mice with intravenous anti-TNF-α antibody or vehicle 30 minutes prior to bilateral, intra-plantar compound 48/80 administration and measured changes in the timing of hind paw withdrawal observed subsequent to mice being placed on a 51oC hotplate. We also assessed changes in tissue swelling, TNF-α gene expression and protein abundance, mast cell degranulation, and neutrophil influx in the hind paw tissue. Findings: We found that TNF-α neutralization significantly blocked thermal hyperalgesia, and reduced early tissue swelling. TNF-α neutralization had no significant effect on mast cell degranulation or neutrophil influx into the tissue, however. Moreover, no changes in TNF-α protein or mRNA levels were detected within 3 hours of administration of compound 48/80. Interpretation:  The neutralizing antibodies likely target pre-formed TNF-α including that stored in the granules of tissue-resident mast cells. Pre-formed TNF-α, released upon degranulation, has immediate effects on nociceptive signaling prior to the induction of neutrophil influx. These early effects on nociceptors are abrogated by TNF-α blockade, resulting in compromised nociceptive withdrawal responses to acute, harmful environmental stimuli.

  2. Vacuum polarization for neutral particles in 2+1 dimensions

    International Nuclear Information System (INIS)

    In 2+1 dimensions there exists a duality between a charged Dirac particle coupled minimally to a background vector potential and a neutral one coupled non-minimally to a background electromagnetic field strength. A constant uniform background electric current induces in the vacuum of the neutral particle a fermion current which is proportional to the background one. A background electromagnetic plane wave induces no current in the vacuum. For constant but nonuniform background electric charge, known results for charged particles can be translated to give the induced fermion number. Some new examples with infinite background electric charge are presented. The induced spin and total angular momentum are also discussed. (author). Letter-to-the-editor

  3. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus).

    Science.gov (United States)

    Wong, Mabel T; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A; Master, Emma R

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36-0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities. PMID:27446004

  4. Pathology and epizootiology of Dirofilaria scapiceps (Leidy, 1886) (Nematoda: Filarioidea) in Sylvilagus floridanus (J.A. Allen) and Lepus americanus erxleben.

    Science.gov (United States)

    Bartlett, C M

    1984-07-01

    Dirofilaria scapiceps was found between the synovial sheath and tendons, i.e., within the tendon sheath, in the ankle region of eastern cottontail rabbits (Sylvilagus floridanus) and snowshoe hares (Lepus americanus). In cottontail rabbits, tendons and sheaths appeared normal and all worms were adults. Only one (4%) of 24 infected rabbits contained dead worms. All female worms were gravid in rabbits killed in late winter or early spring. Microfilaremias in rabbits were high (approximately 30-100 microfilariae/60 microliter blood) and of long duration (at least 8-28 mo), and rabbits were considered normal hosts of D. scapiceps. In some snowshoe hares, tendons and sheaths also appeared normal; however, in other hares a chronic proliferative tenosynovitis, characterized by fibrinous exudate, hyperplasia and hypertrophy of the intima and inflammatory cell (predominantly lymphocytes and plasma cells) infiltration of the intimal and fibrous layers of the synovial sheath led to encapsulation of worms. Dead subadult, dead adult, and live adult worms were found in the ankles of hares; 86 (46%) of 186 infected hares contained some or only dead worms. Fibrosis commonly occurred around dead worms. Dead subadults were also found in subcutaneous connective tissues over the trunk of the body. Degenerate embryos and amorphous material were observed in uteri of some female worms in hares killed in late winter or early spring. Few (1-5 microfilariae/60 microliter blood) or no microfilariae were observed in the peripheral blood of hares and microfilaremias were of short duration (less than 8 mo). Microfilariae in hares are probably trapped and destroyed in the chronic inflammatory lesions in the tendon sheaths since normal, degenerate, and calcified microfilariae were observed in the capsules around adult worms. Some microfilariae might also be destroyed in lymph nodes. Although D. scapiceps can be maintained within snowshoe hare populations, hares are considered abnormal hosts of D

  5. Construction of a subtractive library from hexavalent chromium treated winter flounder (Pseudopleuronectes americanus) reveals alterations in non-selenium glutathione peroxidases

    International Nuclear Information System (INIS)

    Chromium is released during several industrial processes and has accumulated in some estuarine areas. Its effects on mammals have been widely studied, but relatively little information is available on its effects on fish. Gene expression changes are useful biomarkers that can provide information about toxicant exposure and effects, as well as the health of an organism and its ability to adapt to its surroundings. Therefore, we investigated the effects of Cr(VI) on gene expression in the sediment dwelling fish, winter flounder (Pseudopleuronectes americanus). Winter flounder ranging from 300 to 360 g were injected i.p. with Cr(VI) as chromium oxide at 25 μg/kg chromium in 0.15N KCl. Twenty-four hours following injections, winter flounder were euthanized with MS-222 and the livers were excised. Half of the livers were used to make cytosol and the other half were used to isolate mRNA for subtractive hybridization. Subtractive clones obtained were spotted onto nylon filters, which revealed several genes with potentially altered expression due to Cr(VI), including an α class GST, 1-Cys peroxiredoxin (a non-selenium glutathione peroxidase), a P-450 2X subfamily member, two elongation factors (EF-1 gamma and EF-2), and complement component C3. Semi-quantitative RT-PCR was performed and confirmed that Cr(VI) down-regulated complement component C3, an EST, and two potential glutathione peroxidases, GSTA3 and 1-Cys peroxiredoxin. In addition, cytosolic GSH peroxidase activity was reduced, and silver stained SDS-PAGE gels from glutathione-affinity purified cytosol demonstrated that a 27.1 kDa GSH-binding protein was down-regulated greater than 50%. Taken together, Cr(VI) significantly altered the expression of several genes including two potential glutathione peroxidases in winter flounder

  6. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus)

    Science.gov (United States)

    Wong, Mabel T.; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A.; Master, Emma R.

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36–0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25–50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.

  7. Substrate-driven convergence of the microbial community in lignocellulose-amended enrichments of gut microflora from the Canadian beaver (Castor canadensis and North American moose (Alces americanus

    Directory of Open Access Journals (Sweden)

    Mabel Ting eWong

    2016-06-01

    Full Text Available Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fibre (i.e. lignocellulose into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis and North American moose (Alces americanus were enriched under methanogenic conditions for over three years using various wood-derived substrates, including i cellulose (C, ii cellulose + lignosulphonate (CL, iii cellulose + tannic acid (CT, and iv poplar hydrolysate (PH. Substantial improvement in the conversion of amended organic substrates to biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36 to 0.68 ml biogas/ mg COD added, except for enrichments amended with tannic acid where conversion was only about 0.15 ml biogas/ mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate-driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly-defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54 and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.

  8. Condição reprodutiva da betara preta, Menticirrhus americanus (Teleostei, Sciaenidae, na pesca realizada no litoral norte de Santa Catarina, Brasil - DOI: 10.4025/actascibiolsci.v30i4.1230 Reproductive status of Menticirrhus americanus (Teleostei, Sciaenidae in fisheries performed on the Southern coast of Brazil - DOI: 10.4025/actascibiolsci.v30i4.1230

    Directory of Open Access Journals (Sweden)

    Elneison da Rosa Muniz

    2008-11-01

    Full Text Available No litoral brasileiro, a legislação costuma regular as práticas pesqueiras segundo o ciclo de vida das espécies-alvo, mas o fato deste não ser coincidente entre as espécies dominantes nas capturas dificulta o manejo em pescarias multiespecíficas. No litoral de Santa Catarina, o defeso aplica-se apenas à pesca de arrasto, e para tal considera o período reprodutivo do camarão sete-barbas, Xyphopenaeus kroyeri. O presente trabalho investiga a incidência da atividade pesqueira sobre indivíduos em reprodução da betara preta, Menticirrhus americanus, espécie comercialmente apreciada e frequente nas pescarias. As amostragens ocorreram em 2006 e 2007, em desembarques do município de Itapoá, norte do Estado (26°00’S; 48°36’W. Calcularam-se os valores de proporção sexual, frequência de estádios de maturação, índice gonadossomático e tamanho de primeira maturação, e relacionou-se a captura de indivíduos em reprodução com a época do ano e a arte de pesca utilizada. Concluiu-se que a atividade pesqueira incide sobre uma parcela populacional que compreende indivíduos em atividade reprodutiva durante, ao menos, duas estações do ano. Há diferenças entre as artes de pesca: a de arrasto não atinge indivíduos em reprodução; a de caceio atua majoritariamente sobre jovens e em maturação; e a de fundeio, principalmente sobre indivíduos em atividade reprodutiva, sobretudo na primavera e no verão.Fisheries rules usually take into account the life cycle of target species. But as these species differ, multi-specific fisheries prove difficult to be managed. In the southern coast of Brazil (26°00’S, 48°36’W, an annual closed fishing season is exclusive to trawling only, which target species such as the shrimp Xyphopenaeus kroyeri . In this region, the consequences of trawling and gillnets on the life cycles of fish remain unknown. The present work has surveyed the incidence of small-scale fisheries on the reproductive

  9. Landau Quantization of Neutral Particles in an External Field

    CERN Document Server

    Furtado, C; Ribeiro, L R; Furtado, Claudio

    2006-01-01

    The quantum dynamics of an induced electric dipole in the presence of a configuration of crossed electric and magnetic fields is analyzed. This field configuration confines the dipole in a plane and produces a coupling similar to the coupling of a charged particle in the presence of external magnetic field. In this work we investigate the analog of Landau levels in induced electric dipoles in a sistem of neutral particles. The energy levels and eigenfunctions are obtained exactly.

  10. Neutral beams for magnetic fusion

    International Nuclear Information System (INIS)

    Significant advances in forming energetic beams of neutral hydrogen and deuterium atoms have led to a breakthrough in magnetic fusion: neutral beams are now heating plasmas to thermonuclear temperatures, here at LLL and at other laboratories. For example, in our 2XIIB experiment we have injected a 500-A-equivalent current of neutral deuterium atoms at an average energy of 18 keV, producing a dense plasma (1014 particles/cm3) at thermonuclear energy (14 keV or 160 million kelvins). Currently, LLL and LBL are developing beam energies in the 80- to 120-keV range for our upcoming MFTF experiment, for the TFTR tokamak experiment at Princeton, and for the Doublet III tokamak experiment at General Atomic. These results increase our long-range prospects of producing high-intensity beams of energies in the hundreds or even thousands of kilo-electron-volts, providing us with optimistic extrapolations for realizing power-producing fusion reactors

  11. Neutral B meson flavor tagging

    CERN Document Server

    Wilson, R J

    2001-01-01

    We present an investigation of the use of net charge and kaon identification to tag the flavor of neutral B mesons. The net charge of the neutral B meson decay products is zero if all charged particles are used and slightly non-zero if only undiscriminated hadronic final states are used. The net charge of the kaons alone correctly tags the identity of the neutral meson in at least a third of all decays. We have parametrized the particle identification capability of several techniques, such as dE/dx in time projection chambers, LEP/SLC ring-imaging chambers and an enhanced BaBar DIRC. Using these parametrisations we compare the relative tagging power of each technique to that of an ideal detector. (8 refs).

  12. ATF neutral beam injection system

    International Nuclear Information System (INIS)

    The Advanced Toroidal Facility is a stellarator torsatron being built at Oak Ridge National Laboratory to investigate improved plasma confinement schemes. Plasmas heating will be carried out predominantly by means of neutral beam injection. This paper describes the basic parameters of the injection system. Numerical calculations were done to optimize the aiming of the injectors. The results of these calculations and their implications on the neutral power to the machine are elaborated. The effects of improving the beam optics and altering the focal length on the power transmitted to the plasma are discussed

  13. Comparison of experimental data and three-dimensional simulations of ion beam neutralization from the Neutralized Transport Experiment

    International Nuclear Information System (INIS)

    The Neutralized Transport Experiment at Lawrence Berkeley National Laboratory has been designed to study the final focus and neutralization of high perveance ion beams [E. Henestroza, S. Eylon, P. Roy, S. Yu, A. Anders, F. Bieniosek, W. Greenway, B. Logan, R. MacGill, D. Shuman et al., Phys. Rev. ST-Accel. Beams 7, 083501 (2004)]. Preformed plasmas in the last meter before the target of the scaled experiment provide a source of electrons which neutralize the ion current and prevent the space-charge-induced spreading of the beam spot. Neutralized Transport Experiment physics issues are discussed and experimental data are analyzed and compared with three-dimensional (3D) particle-in-cell simulations. Along with detailed target images, 4D phase-space data at the entrance of the neutralization region have been acquired. These data are used to provide a more accurate beam distribution with which to initialize the simulation. Previous treatments have used various idealized beam distributions which lack the detailed features of the experimental ion beam images. Simulation results are compared with experimental measurements for K+ ion beams (∼250 keV) with dimensionless perveance of (1-7)x10-4. In both simulation and experiment, the deduced beam charge neutralization is encouraging for heavy ion fusion and high energy density physics applications

  14. Microsomal estradiol 2-hydroxylase regulation in the marine fish winter flounder (Pseudopleuronectes americanus) and scup (Stenotomus chrysops)

    International Nuclear Information System (INIS)

    2-Hydroxyestradiol (2-OH E2) is a major E2 metabolite in mammals. The 2-hydroxylation of E2 by liver microsomes from two marine fish species, measured as 3H liberation from 2-[3H]-E2, was cytochrome, P-450 mediated. 2-OH-E2 represented as much as 80% of microsomal E2 metabolism. Microsomes from mature female winter flounder formed 0.337 +/- 0.192 of nmol 2-OH E2/min/nmol P-450 compared to the male activity of 0.128 +/- 0.030. Mature female scup also had higher E2-2-OH activities than male scup. E2 2-hydroxylation by microsomes from β-naphthoflavone (BNF)-treated immature scup declined to 0.498 +/- 0.083 nmol/min/nmol P-450 from the control value of 1.05 +/- 0.113. Polyclonal antibodies to P-450E, the major BNF-inducible scup P-450 isozyme, stimulated 2-hydroxylation in microsomes from BNF-treated scup by 80% but did not affect the activity in control microsomes. This first description of 2-OH E2 formation by teleosts shows that it is a major microsomal activity in fish. The sex differences in E2 2-hydroxylation indicate the catalysts is regulated by sex hormones. Stimulation of this activity by anti-P-450E suggests that BNF-induced P-450 isozymes with intrinsically low E2 2-hydroxylase activity may also bind factors necessary for E2 metabolism by other isozymes. In teleosts, then, E2 metabolism might be governed by both endogenous and exogenous factors

  15. Charm and fancy changing neutral currents with five quarks

    International Nuclear Information System (INIS)

    A five-quark weak interaction model based on the SU(2) X U(1) X U(1)' gauge group is proposed. The fifth quark f with fancy flavor has electric charge 2/3. The model induces the charm and fancy changing neutral currents in a natural fashion which are responsible for substantial D0 - anti D0 mixing to explain the observed wrong-sign dimuon events. However, these flavor changing neutral currents do not couple to leptons, thus forbidding trimuons to appear as the experiments indicate thus far. The authors discuss in addition how the model can be extended to a vector-like theory. (Auth.)

  16. Money neutrality: Rethinking the myth

    Directory of Open Access Journals (Sweden)

    Issaoui Fakhri

    2015-01-01

    Full Text Available Considered as an axiomatic basis of classical, neoclassical, and monetarist theories, the long-run money neutrality assumption does not always seem to be verified. Indeed, in our view, the money, in the sense of M2, can constitute a long-run channel of growth transmission. Thus, this paper examines the long-term relationship among money supply (M2, income (GDP, and prices (CPI. The subprime crisis in 2007 has shown that the demand for money does not only meet motives of transaction, precaution, and speculation but also of fictional or quasi-fictional future demands due to the fact that they are created without real counterparts. The capacity of production systems in developed countries to respond to increases in money supply by creating more wealth, involves the assumption of money neutrality in the long-run. However, in developing countries, the excess of money supply may lead to inflation trends. The present study has confirmed the long-term non-neutrality of money supply in the USA, and its neutrality in Gabon and Morocco.

  17. ITER Neutral Beam Injection System

    International Nuclear Information System (INIS)

    A Japanese design proposal of the ITER Neutral Beam Injection System (NBS) which is consistent with the ITER common design requirements is described. The injection system is required to deliver a neutral deuterium beam of 75MW at 1.3MeV to the reactor plasma and utilized not only for plasma heating but also for current drive and current profile control. The injection system is composed of 9 modules, each of which is designed so as to inject a 1.3MeV, 10MW neutral beam. The most important point in the design is that the injection system is based on the utilization of a cesium-seeded volume negative ion source which can produce an intense negative ion beam with high current density at a low source operating pressure. The design value of the source is based on the experimental values achieved at JAERI. The utilization of the cesium-seeded volume source is essential to the design of an efficient and compact neutral beam injection system which satisfies the ITER common design requirements. The critical components to realize this design are the 1.3MeV, 17A electrostatic accelerator and the high voltage DC acceleration power supply, whose performances must be demonstrated prior to the construction of ITER NBI system. (author)

  18. Net Neutrality in the Netherlands

    NARCIS (Netherlands)

    N. van Eijk

    2014-01-01

    The Netherlands is among the first countries that have put specific net neutrality standards in place. The decision to implement specific regulation was influenced by at least three factors. The first was the prevailing social and academic debate, partly due to developments in the United States. The

  19. Neutralization kinetics for polonium-218

    International Nuclear Information System (INIS)

    In a well-defined experimental system the neutralization of polonium-218 ions was investigated as a function of the physical and chemical properties of the controlled composition atmosphere. The diffusion coefficient of polonium-218 under various concentrations of trace gas NO2 in nitrogen was measured. The mobilities of Po+ and PoO2+ are determined by combining experimental results with a computer model of the system. Three neutralization mechanisms were individually studied. The small-ion recombination rate has been found to be proportional to the square root of radon concentration. The electron-scavenging mechanism is responsible for the neutralization of Po+ in NO2 or H2O in nitrogen. When PoO2+ is formed, the electron-transfer mechanism dominates the neutralization process. The electron is transferred to PoO2+ from molecules with lower ionization potentials. The ionization molecules with lower ionization potentials. The ionization potential of PoO2+ is also determined to be 10.44 +/- 0.05 eV

  20. Neutral Models with Generalised Speciation

    NARCIS (Netherlands)

    Haegeman, Bart; Etienne, Rampal S.

    2009-01-01

    Hubbell's neutral theory claims that ecological patterns such as species abundance distributions can be explained by a stochastic model based on simple assumptions. One of these assumptions, the point mutation assumption, states that every individual has the same probability to speciate. Etienne et

  1. Immunogenic peptides comprising a T-helper epitope and a B-cell neutralizing antibody epitope

    Science.gov (United States)

    Haynes, Barton F.; Korber, Bette T.; De Lorimier, Robert M.

    2006-12-26

    The present invention relates, generally, to a polyvalent immunogen and, more particularly, to a method of inducing neutralizing antibodies against HIV and to a polyvalent immunogen suitable for use in such a method.

  2. Coherently walking, rocking and blinding single neutral atoms

    International Nuclear Information System (INIS)

    Advances in the preparation and detection, but most importantly in the coherent manipulation of single neutral atoms have allowed the observation of intriguing phenomena of quantum physics in recent years. We discuss developments to prepare and detect single neutral atoms in a one-dimensional optical lattice potential with single site resolution. Moreover, using two different experimental techniques, a state-dependent optical lattice potential on the one hand and a high-finesse optical cavity on the other hand, we have obtained coherent control over single neutral atoms. The former has enabled us to observe the quantum walk of atoms in position space, and to coherently control the motion of trapped atoms via microwave radiation. The latter offers a means to non-destructively detect the atomic spin state, thereby revealing quantum jumps of single atoms, or the altered optical properties of single atoms when subject to electromagnetically-induced transparency.

  3. High power neutral beam systems

    International Nuclear Information System (INIS)

    Spurred by the requirement to supply megawatts of power to heat magnetically confined plasmas to temperatures of interest for fusion research, a new class of low energy, high power accelerators termed neutral beam injectors has been developed. Industry has played an important role in building upon technology advances at the national laboratories to engineer neutral beam injectors to meet the needs of specific users. A brief retrospective of the field is presented, with emphasis upon one particular application, that of DIII-D, a large tokamak at General Atomics. In this instance, the role of industry has been especially extensive because the user/system integrator is itself an industrial concern. 4 refs., 7 figs., 2 tabs

  4. Money neutrality: Rethinking the myth

    OpenAIRE

    Issaoui Fakhri; Boufateh Talel; Guesmi Mourad

    2015-01-01

    Considered as an axiomatic basis of classical, neoclassical, and monetarist theories, the long-run money neutrality assumption does not always seem to be verified. Indeed, in our view, the money, in the sense of M2, can constitute a long-run channel of growth transmission. Thus, this paper examines the long-term relationship among money supply (M2), income (GDP), and prices (CPI). The subprime crisis in 2007 has shown that the demand for money does not only...

  5. Optimization of Neutral Atom Imagers

    Science.gov (United States)

    Shappirio, M.; Coplan, M.; Balsamo, E.; Chornay, D.; Collier, M.; Hughes, P.; Keller, J.; Ogilvie, K.; Williams, E.

    2008-01-01

    The interactions between plasma structures and neutral atom populations in interplanetary space can be effectively studied with energetic neutral atom imagers. For neutral atoms with energies less than 1 keV, the most efficient detection method that preserves direction and energy information is conversion to negative ions on surfaces. We have examined a variety of surface materials and conversion geometries in order to identify the factors that determine conversion efficiency. For chemically and physically stable surfaces smoothness is of primary importance while properties such as work function have no obvious correlation to conversion efficiency. For the noble metals, tungsten, silicon, and graphite with comparable smoothness, conversion efficiency varies by a factor of two to three. We have also examined the way in which surface conversion efficiency varies with the angle of incidence of the neutral atom and have found that the highest efficiencies are obtained at angles of incidence greater then 80deg. The conversion efficiency of silicon, tungsten and graphite were examined most closely and the energy dependent variation of conversion efficiency measured over a range of incident angles. We have also developed methods for micromachining silicon in order to reduce the volume to surface area over that of a single flat surface and have been able to reduce volume to surface area ratios by up to a factor of 60. With smooth micro-machined surfaces of the optimum geometry, conversion efficiencies can be increased by an order of magnitude over instruments like LENA on the IMAGE spacecraft without increase the instruments mass or volume.

  6. The Economics of Network Neutrality

    OpenAIRE

    Nicholas Economides; Benjamin Hermalin

    2010-01-01

    Pricing of Internet access has been characterized by two properties. Parties are directly billed only by the Internet Service Provider (ISP) through which they connect to the Internet and the ISP charges them on the basis of the amount of information transmitted rather than its content. These properties define a regime known as “network neutrality.” In 2005, some large ISPs proposed that application and content providers directly pay them additional fees for accessing the ISPs’ residential cl...

  7. Net neutrality and investment incentives

    OpenAIRE

    Choi, Jay Pil; Kim, Byung-Cheol

    2008-01-01

    This paper analyzes the effects of net neutrality regulation on investment incentives for Internet service providers (ISPs) and content providers (CPs), and their implications for social welfare. We show that the ISP's decision on the introduction of discrimination across content depends on a potential trade-off between network access fee and the revenue from the trade of the first-priority. Concerning the ISP's investment incentives, we find that capacity expansion affects the sale price of ...

  8. Neutral and Charged Anyon Fluids

    OpenAIRE

    Hosotani, Yutaka

    1993-01-01

    (Review) Properties of neutral and charged anyon fluids are examined, with the main focus on the question whether or not a charged anyon fluid exhibits a superconductivity at zero and finite temperature. Quantum mechanics of anyon fluids is precisely described by Chern-Simons gauge theory. The random phase approximation (RPA), the linearized self-consistent field method (SCF), and the hydrodynamic approach employed in the early analysis of anyon fluids are all equivalent. Relations and differ...

  9. Steady state neutral beam injector

    International Nuclear Information System (INIS)

    Learning from operational reliability of neutral beam injectors in particular and various heating schemes including RF in general on TFTR, JET, JT-60, it has become clear that neutral beam injectors may find a greater role assigned to them for maintaining the plasma in steady state devices under construction. Many technological solutions, integrated in the present day generation of injectors have given rise to capability of producing multimegawatt power at many tens of kV. They have already operated for integrated time >105 S without deterioration in the performance. However, a new generation of injectors for steady state devices have to address to some basic issues. They stem from material erosion under particle bombardment, heat transfer > 10 MW/m2, frequent regeneration of cryopanels, inertial power supplies, data acquisition and control of large volume of data. Some of these engineering issues have been addressed to in the proposed neutral beam injector for SST-1 at our institute; the remaining shall have to wait for the inputs of the database generated from the actual experience with steady state injectors. (author)

  10. Plasma/Neutral-Beam Etching Apparatus

    Science.gov (United States)

    Langer, William; Cohen, Samuel; Cuthbertson, John; Manos, Dennis; Motley, Robert

    1989-01-01

    Energies of neutral particles controllable. Apparatus developed to produce intense beams of reactant atoms for simulating low-Earth-orbit oxygen erosion, for studying beam-gas collisions, and for etching semiconductor substrates. Neutral beam formed by neutralization and reflection of accelerated plasma on metal plate. Plasma ejected from coaxial plasma gun toward neutralizing plate, where turned into beam of atoms or molecules and aimed at substrate to be etched.

  11. Net Neutrality, Business Models, and Internet Interconnection

    OpenAIRE

    Jay Pil Choi; Doh-Shin Jeon; Byung-Cheol Kim

    2015-01-01

    We analyze the effect of net neutrality regulation in a two-sided market framework when content is heterogeneous in its sensitivity to delivery quality. We characterize the equilibrium in a neutral network constrained to offer the same quality vis-à-vis a non neutral network where Internet service providers are allowed to engage in second degree price discrimination with a menu of quality-price pairs. We find that the merit of net neutrality regulation depends crucially on content providers' ...

  12. 46 CFR 502.404 - Neutrals.

    Science.gov (United States)

    2010-10-01

    ... Dispute Resolution § 502.404 Neutrals. (a) A neutral may be a permanent or temporary officer or employee of the Federal Government or any other individual who is acceptable to the parties to a dispute... Maritime Commission Dispute Resolution Specialist will seek to provide a neutral in dispute...

  13. Neutrality in mediation: an ambiguous ethical value

    OpenAIRE

    Bailey, Paul

    2014-01-01

    Mediator neutrality would appear, by definition, to be a necessary and required ethical principle for all mediators to practice. But what is meant by neutrality in mediation? Is it practically possible to be completely neutral between parties in mediation while at the same time being fair to both of them? This paper attempts to answer these two questions.

  14. Natural suppression of flavour-changing neutral currents in supersymmetric gauge theories

    International Nuclear Information System (INIS)

    Induced flavour-changing neutral currents (FCNC) in supersymmetric unified theories are investigated both in models with the standard SU(2)sub(L) x U(1) gauge symmetry and in models with an extra U tilde(1) gauge symmetry. Supersymmetric extension of the natural flavour conservation laws for neutral currents is obtained by adding a condition regarding the assumed type of supersymmetry breaking. This condition ensures no direct flavour-changing couplings of neutral gauge-Higgs fermions and at the same time is necessary and sufficient for the natural suppression of the induced FCNC. It is found that in the class of models satisfying the new condition the contribution of the scalar partners of quarks to the induced strangeness-changing neutral current is comparable to that of the quarks in K sub(L) → μantiμ, while it is negligibly small in K sub(L)-K sub(S) mass difference. (author)

  15. Selfcoelum lamothei n. sp. (Digenea: Cyclocoelidae: Cyclocoelinae from the air sacs of the long-billed curlew, Numenius americanus (Scolopacidae, from the Galveston, Texas area, USA Selfcoelum lamothei, n. sp. (Digenea: Cyclocoelidae: Cyclocoelinae de los sacos aéreos del playero de pico largo, Numenius americanus (Scolopacidae, del área del condado de Galveston, Texas, EUA

    Directory of Open Access Journals (Sweden)

    Charles K. Blend

    2008-08-01

    Full Text Available Fourteen specimens of a new species of cyclocoelid, Selfcoelum lamothei n. sp. (Digenea: Cyclocoelidae: Cyclocoelinae, from the air sacs of a long-billed curlew, Numenius americanus Bechstein (Scolopacidae, collected from the Galveston area, Galveston County, Texas, USA, were examined. The new species has an intertesticular ovary that forms a triangle with the testes, placing it in Cyclocoelinae Stossich, 1902. The new species is most similar to Selfcoelum capellum (Khan, 1935 n. comb., but differs from this species by lacking an oral sucker and by having a somewhat larger ovary, larger testes, a smaller posttesticular space, a larger cirrus sac, larger eggs, and the vitelline follicles of S. lamothei n. sp. are more bulky making the vitelline fields more laterally extensive, and more anteriorly distributed (reaching anteriorly to the level of the pharynx compared to the level of the cecal bifurcation than those of S. capellum. The new species can be distinguished from the 2 species currently assigned to Selfcoelum Dronen, Gardner and Jiménez, 2006, S. brasilianum (Stossich, 1902 and S. limnodromi Dronen, Gardner and Jiménez, 2006, by having an intercecal uterus rather than having uterine loops that overreach the ceca laterally. The genus Selfcoelum should be emended to include those species where the uterus is either intercecal or where the uterine loops overreach the ceca laterally and those species with or without an oral sucker.Se examinaron 14 ejemplares de una nueva especie de ciclocélido, Selfcoelum lamothei n. sp. (Digenea: Cyclocoelidae: Cyclocoelinae que es parásito de los sacos aéreos del playero de pico largo, Numenius americanus Bechstein (Scolopacidae, recolectados en el condado de Galveston, Texas, EUA. La especie nueva se caracteriza por presentar el ovario en posición intertesticular, formando un triángulo con relación a los testículos. Este rasgo sitúa a la nueva especie entre los Cyclocoelinae Stossich, 1902

  16. Gas Flow Measurements of a Novel Geometry for Neutral Beam Neutralizers.

    Science.gov (United States)

    Pirkle, David Ross

    The gas flow characteristics of a novel geometry (pumped neutralizer) for decreasing the flow of gas from neutral beam neutralizers were measured and compared with a conventional (passive) neutralizer. A passive neutralizer is typically a duct attached to the ion source. For the pumped neutralizer the top and bottom surfaces of the duct are replaced by a Venetian blind geometry which opens into ballast vacuum pumping volumes. With guidance from a Monte Carlo program which models gas flow at low pressure, a one-half scale model with pumped neutralizer geometry was built and compared to a passive neutralizer with comparable dimensions. With the vanes on the pumped neutralizer opened to 55 degrees, the line density of the pumped neutralizer was 1.6 times less than the passive neutralizer. The amount of gas flowing from the exit of the pumped neutralizer was from 2 to 5 times less than the amount flowing from the pumped neutralizer. Hence, the pumped neutralizer geometry appears to be a promising method of limiting the flow of gas from neutral beam gas cell neutralizers.

  17. ORNL positive ion neutral beam program

    International Nuclear Information System (INIS)

    The neutral beam group at Oak Ridge National Laboratory has constructed neutral beam generators for the ORMAK and PLT devices, is presently constructing neutral beam devices for the ISX and PDX devices, and is contemplating the construction of neutral beam systems for the advanced TNS device. These neutral beam devices stem from the pioneering work on ion sources of G. G. Kelley and O. B. Morgan. We describe the ion sources under development at this Laboratory, the beam optics exhibited by these sources, as well as some theoretical considerations, and finally the remainder of the beamline design

  18. Fluorescence measurements of expanding strongly-coupled neutral plasmas

    CERN Document Server

    Cummings, E A; Durfee, D S; Bergeson, S D

    2005-01-01

    We report new detailed density profile measurements in expanding strongly-coupled neutral plasmas. Using laser-induced fluorescence techniques, we determine plasma densities in the range of 10^5 to 10^9/cm^3 with a time resolution limit as small as 7 ns. Strong-coupling in the plasma ions is inferred directly from the fluorescence signals. Evidence for strong-coupling at late times is presented, confirming a recent theoretical result.

  19. Advanced neutral-beam technology

    International Nuclear Information System (INIS)

    Extensive development will be required to achieve the 50- to 75-MW, 175- to 200-keV, 5- to 10-sec pulses of deuterium atoms envisioned for ETF and INTOR. Multi-megawatt injector systems are large (and expansive); they consist of large vacuum tanks with many square meters of cryogenic pumping panels, beam dumps capable of dissipating several megawatts of un-neutralized beam, bending magnets, electrical power systems capable of fast turnoff with low (capacity) stored energy, and, of course, the injector modules (ion sources and accelerators). The technology requirements associated with these components are described

  20. Structure of Rotavirus Outer-Layer Protein VP7 Bound with a Neutralizing Fab

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, Scott T.; Settembre, Ethan C.; Trask, Shane D.; Greenberg, Harry B.; Harrison, Stephen C.; Dormitzer, Philip R.; (Stanford-MED); (CH-Boston)

    2009-06-17

    Rotavirus outer-layer protein VP7 is a principal target of protective antibodies. Removal of free calcium ions (Ca{sup 2+}) dissociates VP7 trimers into monomers, releasing VP7 from the virion, and initiates penetration-inducing conformational changes in the other outer-layer protein, VP4. We report the crystal structure at 3.4 angstrom resolution of VP7 bound with the Fab fragment of a neutralizing monoclonal antibody. The Fab binds across the outer surface of the intersubunit contact, which contains two Ca{sup 2+} sites. Mutations that escape neutralization by other antibodies suggest that the same region bears the epitopes of most neutralizing antibodies. The monovalent Fab is sufficient to neutralize infectivity. We propose that neutralizing antibodies against VP7 act by stabilizing the trimer, thereby inhibiting the uncoating trigger for VP4 rearrangement. A disulfide-linked trimer is a potential subunit immunogen.

  1. Simulations of Atmospheric Neutral Wave Coupling to the Ionosphere

    Science.gov (United States)

    Siefring, C. L.; Bernhardt, P. A.

    2005-12-01

    The densities in the E- and F-layer plasmas are much less than the density of background neutral atmosphere. Atmospheric neutral waves are primary sources of plasma density fluctuations and are the sources for triggering plasma instabilities. The neutral atmosphere supports acoustic waves, acoustic gravity waves, and Kelvin Helmholtz waves from wind shears. These waves help determine the structure of the ionosphere by changes in neutral density that affect ion-electron recombination and by neutral velocities that couple to the plasma via ion-neutral collisions. Neutral acoustic disturbances can arise from thunderstorms, chemical factory explosions and intentional high-explosive tests. Based on conservation of energy, acoustic waves grow in amplitude as they propagate upwards to lower atmospheric densities. Shock waves can form in an acoustic pulse that is eventually damped by viscosity. Ionospheric effects from acoustic waves include transient perturbations of E- and F-Regions and triggering of E-Region instabilities. Acoustic-gravity waves affect the ionosphere over large distances. Gravity wave sources include thunderstorms, auroral region disturbances, Space Shuttle launches and possibly solar eclipses. Low frequency acoustic-gravity waves propagate to yield traveling ionospheric disturbances (TID's), triggering of Equatorial bubbles, and possible periodic structuring of the E-Region. Gravity wave triggering of equatorial bubbles is studied numerically by solving the equations for plasma continuity and ion velocity along with Ohms law to provide an equation for the induced electric potential. Slow moving gravity waves provide density depressions on bottom of ionosphere and a gravitational Rayleigh-Taylor instability is initiated. Radar scatter detects field aligned irregularities in the resulting plasma bubble. Neutral Kelvin-Helmholtz waves are produced by strong mesospheric wind shears that are also coincident with the formation of intense E-layers. An

  2. Laser sputter neutral mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    King, B.V.; Clarke, M.; Hu, H.; Betz [Newcastle Univ., NSW (Australia). Dept. of Physics

    1993-12-31

    Laser sputter neutral mass spectrometry (LSNMS) is an emerging technique for highly sensitive surface analysis. In this technique a target is bombarded with a pulsed beam of keV ions. The sputtered particles are intercepted by a high intensity pulsed laser beam above the surface and ionised with almost 100% efficiency. The photions may then be mass analysed using a quadrupole or, more commonly, using time of flight (TOF) techniques. In this method photoions are extracted from the ionisation region, accelerated to a known energy E{sub o} and strike a channelplate detector a distance `d` away. The flight time `t` of the photoions is then related to their mass by `d` {radical}m / {radical} 2E{sub o} so measurement of `t` allows mass spectra to be obtained. It is found that LSNMS is an emerging technique of great sensitivity and flexibility, useful for both applied analysis and to investigate basic sputtering processes. 4 refs., 3 figs.

  3. Happy birthday, little neutral one

    International Nuclear Information System (INIS)

    This article looks at the history of the neutrino particle, a tiny neutral particle which reacts only with the weak force. Its existence was originally postulated by Wolfgang Pauli in 1930, to explain beta decay energy conservation but because of the extreme experimental difficulties involved, neutrinos were not observed experimentally until 1956. Notwithstanding this the neutrino has become a valuable tool in high energy physics. Neutrino beams are used to probe matter and were used to reveal the existence of quarks within the particles once viewed as elementary, the proton and neutron. Cosmic neutrinos may be detected in the Deep Underwater Muon and Neutrino Detector off the coast of Hawaii and the Moon itself is a target for ultra high energy neutrinos in a Russian experiment to detect cascades of charge particles produced by these neutrinos in ice in the Antarctic. (UK)

  4. After treatment ends: neutral time.

    Science.gov (United States)

    Hurt, G J; McQuellon, R P; Barrett, R J

    1994-01-01

    For persons diagnosed with cancer, the remission period may be marked by increased anxiety and distress. While the medical team may view remission as an eagerly anticipated milestone, the decreased medical surveillance during this time can cause a heightened fear of recurrence for the patient. One author has called this period of remission "neutral time," a time characterized by uncertainty. The safety signal hypothesis, developed by Martin Seligman, may help to explain the anxiety experienced by some patients during the remission period. Because cancer is frequently a silent disease with no overt symptoms, patients in remission often have no safety signal to indicate that the disease will not return. A case study is presented and discussed in light of these two concepts. PMID:7697080

  5. Determination of the neutral to charged current cross section ratio for neutrino interactions on protons

    International Nuclear Information System (INIS)

    About 2000 neutral induced interactions observed inside the hydrogen filled TST in BEBC have been analysed. The data were obtained from an exposure to the vsub(μ) wide band beam at the CERN SPS. A separation of these events into charged current, neutral current and neutral hadron induced interactions have been achieved using a multidimensional kinematic analysis. The neutral to charged current cross section ratio for vsub(μ) interactions on free protons has been determined avoiding the drastic cuts on the data inherent in previous experiments. The result Rsub(P)sup(v)=0.47 +- 0.04 is compatible with those measurements and the prediction of the standard SU(2) x U(1) model for sinsub(THETA)2sub(W)=0.18 +- 0.04. (orig.)

  6. Determination of the neutral to charged current cross section ratio for neutrino interactions on protons

    Energy Technology Data Exchange (ETDEWEB)

    Armenise, N.; Calicchio, M.; Erriquez, O.; Fogli-Muciaccia, M.T.; Natali, S.; Nuzzo, S.; Ruggieri, F. (Bari Univ. (Italy). Ist. di Fisica; Istituto Nazionale di Fisica Nucleare, Bari (Italy)); Belusevic, R.; Colley, D.C.

    1983-03-17

    About 2000 neutral induced interactions observed inside the hydrogen filled TST in BEBC have been analysed. The data were obtained from an exposure to the vsub(..mu..) wide band beam at the CERN SPS. A separation of these events into charged current, neutral current and neutral hadron induced interactions have been achieved using a multidimensional kinematic analysis. The neutral to charged current cross section ratio for vsub(..mu..) interactions on free protons has been determined avoiding the drastic cuts on the data inherent in previous experiments. The result Rsub(P)sup(v)=0.47 +- 0.04 is compatible with those measurements and the prediction of the standard SU(2) x U(1) model for sinsub(THETA)/sup 2/sub(W)=0.18 +- 0.04.

  7. Determination of the neutral to charged current cross section ratio for neutrino interactions on protons

    Science.gov (United States)

    Armenise, N.; Calicchio, M.; Erriquez, O.; Fogli-Muciaccia, M. T.; Natali, S.; Nuzzo, S.; Ruggieri, F.; Belusevic, R.; Colley, D. C.; Jones, G. T.; O'Neale, S.; Sewell, S.; Votruba, M. F.; Bertrand, D.; Moreels, J.; Sacton, J.; Vander Velde-Wilquet, C.; Van Doninck, W.; Brisson, V.; Francois, T.; Petiau, P.; Cooper, A. M.; Guy, J. G.; Michette, A. G.; Tyndel, M.; Venus, W.; Baton, J. P.; Gerbier, G.; Kochowski, C.; Neveu, M.; Alamatsaz, H.; Azemoon, T.; Bartley, J. H.; Parker, M. A.; BEBC TST Neutrino Collaboration

    1983-03-01

    About 2000 neutral induced interactions observed inside the hydrogen filled TST in BEBC have been analysed. The data were obtained from an exposure to the vμ wide band beam at the CERN SPS. A separation of these events into charged current, neutral current and neutral hadron induced interactions have been achieved using a multidimensional kinematic analysis. The neutral to charged current cross section ratio for vμ interactions on free protons has been determined avoiding the drastic cuts on the data inherent in previous experiments. The result RPv = 0.47 ± 0.04 is compatible with those measurements and the prediction of the standard SU (2) × U (1) model for sin 2θW = 0.18 ± 0.04.

  8. Tenure neutral and equitable housing taxation

    OpenAIRE

    Thalmann, Philippe

    2007-01-01

    Equity and neutrality are distinct concepts in housing taxation and weak and strong tenure neutrality should be distinguished. When a tax system is tested for those criteria, the taxes paid by landlords must be included, as they affect the rents renters pay. This paper defines appropriate tests, applies them to a stylised tax system and proposes tax changes designed to restore tenure equity and/or neutrality. It shows how the homeowner's implicit income should be computed for taxes to be fund...

  9. Irish neutrality and the Lisbon Treaty

    OpenAIRE

    Devine, Karen

    2009-01-01

    One of the main themes of the conference focused on the definition of neutrality. The convenors of the conference frequently raised the question, “what do we mean when we talk of ‘neutrality’?” This paper explains the differences between the public concept of neutrality and government concepts of ‘military neutrality’ and evaluates whether the Lisbon Treaty, including the June 2009 ‘clarification’ declarations, contravene or protect neutrality.

  10. Evaluating Neutrality Properties of Corporate Tax Reforms

    OpenAIRE

    Michael P. Devereux; Simon Loretz

    2010-01-01

    We propose a methodology for assessing the neutrality of corporate tax reform proposals in an open economy. The methodology identifies variation in effective tax rates to assess the proximity of a tax system to capital export neutrality (CEN) and to market neutrality (MN, which holds if all potential competitors in a single market face the same effective tax rate). We apply the methodology to two reform options in the EU. Optional international loss consolidation would move the EU tax system ...

  11. Neutral Higgs effects on rare decay B→Xsl+l- in the T2HDM

    International Nuclear Information System (INIS)

    We calculate the new physics contributions to the branching ratios of the rare decays B→Xsl+l- (l=e,μ) induced by neutral Higgs bosons loop diagrams in the top quark two-Higgs-doublet model (T2HDM). From the numerical calculations, we find that (a) the neutral Higgs boson's correction to B→Xsl+l- decays interferes constructively with its standard model counterpart, but small in magnitude; (b) the neutral Higgs contributions to the branching ratio of B→Xsl+l- decay can be neglected safely if their masses are larger than 100GeV and tanβ≤40. (authors)

  12. Anticorpos neutralizantes contra o vírus da Diarréia Viral Bovina (BVDV: comparação entre um imunógeno experimental atenuado e três vacinas comerciais inativadas Vaccination-induced neutralizing antibodies against bovine viral diarrhea virus (BVDV: comparison between an experimental modified-live vaccine and three comercial inactivated vaccines

    Directory of Open Access Journals (Sweden)

    Marcelo de Lima

    2005-02-01

    Full Text Available Os títulos e duração de anticorpos neutralizantes contra o vírus da Diarréia Viral Bovina (BVDV induzidos por uma vacina experimental atenuada (vacina A: dose única foram comparados com os induzidos por três vacinas comerciais inativadas (B, C e D: duas doses com intervalo de 30 dias. Trinta dias após a vacinação (vacina A ou após a segunda dose (vacinas B, C e D, anticorpos neutralizantes contra o BVDV-1 foram detectados em todos os animais (12/12 do grupo A (título médio geométrico GMT=1612,7; em 32 de 36 animais do grupo B (GMT=14,3; 22 de 28 do grupo C (GMT=25,1; e em 16 de 30 do grupo D (GMT=40,0. Anticorpos frente ao BVDV-2 foram detectados em todos os animais do grupo A (GMT=151,0; em 27 de 36 do grupo B (GMT=10,0; 12 de 28 do grupo C (GMT=11,5 e em 10 de 30 animais do grupo D (GMT=10,0. No dia 180 após a vacinação, o número de animais que ainda apresentava anticorpos contra o BVDV-1 e os GMTs para cada grupo foram: vacina A (12/12, GMT=905,0; vacina B (30/36, GMT=28,3; vacina C (20/28, GMT=28,3; vacina D (14/30, GMT=16,1; e contra o BVDV-2 foram: vacina A (12/12, GMT=56,6; vacina B (18/36, GMT=16,8; vacina C (10/28, GMT=21,6 e vacina D (6/30, GMT=16,1. Os títulos médios (GMTs induzidos pela vacina A foram significativamente superiores aos demais, tanto para o BVDV-1 (PThe titers and duration of neutralizing antibodies against bovine viral diarrhea virus (BVDV induced by an experimental attenuated vaccine (vaccine A: one dose were compared to those induced by three commercial inactivated ones (B, C and D: two doses at a 30 day interval. Thirty days after vaccination (vaccine A or the second dose (vaccines B, C and D, neutralizing antibodies to BVDV-1 were detected in all calves (12/12 from group A (mean geometric titer GMT=1612.7; in 32 out of 36 from group B (GMT=14.3; 22/28 from group C (GMT=25.1; 16/30 from group D (GMT=40.0. Antibodies reacting with BVDV-2 were detected in all animals from group A (GMT=151.0; 27

  13. Unconventional electromagnetic mode in neutral Weyl semimetals

    Science.gov (United States)

    Ferreiros, Yago; Cortijo, Alberto

    2016-05-01

    We study light propagation in a neutral Weyl semimetal with the Fermi level lying at the Weyl nodes in the weak self-interacting regime. The nontrivial topology induces a screening effect in one of the two transverse gauge fields, for which we find two branches of attenuated collective excitations. In addition to the known topologically gapped photon mode, a different massless and slightly damped excitation appears. Strikingly, at low energies, this excitation has a linear dispersion and it propagates with the same velocity as the electrons, while at energies well above the electron-hole continuum threshold it behaves as a massive attenuated photon with velocity similar to the speed of light in the material. There is a crossover at a certain momentum in the direction perpendicular to the separation of the Weyl nodes above which this gapless mode enters into an overdamped regime. Regarding the unscreened gauge field, we show that it is also attenuated, which is a nontopological property shared by Dirac semimetals as well.

  14. Measurement of νμ-induced charged-current neutral pion production cross sections on mineral oil at Eν is an element of 0.5-2.0 GeV

    International Nuclear Information System (INIS)

    Using a custom 3-Cerenkov ring fitter, we report cross sections for νμ-induced charged-current single π0 production on mineral oil (CH2) from a sample of 5810 candidate events with 57% signal purity over an energy range of 0.5-2.0 GeV. This includes measurements of the absolute total cross section as a function of neutrino energy, and flux-averaged differential cross sections measured in terms of Q2, μ- kinematics, and π0 kinematics. The sample yields a flux-averaged total cross section of (9.2±0.3stat±1.5syst)x10-39 cm2/CH2 at mean neutrino energy of 0.965 GeV.

  15. Detection of the level of fluoride in the commercially available toothpaste using laser induced breakdown spectroscopy with the marker atomic transition line of neutral fluorine at 731.1 nm

    Science.gov (United States)

    Gondal, M. A.; Maganda, Y. W.; Dastageer, M. A.; Al Adel, F. F.; Naqvi, A. A.; Qahtan, T. F.

    2014-04-01

    Fourth harmonic of a pulsed Nd:YAG laser (wavelength 266 nm) in combination with high resolution spectrograph equipped with Gated ICCD camera has been employed to design a high sensitive analytical system. This detection system is based on Laser Induced Breakdown Spectroscopy and has been tested first time for analysis of semi-fluid samples to detect fluoride content present in the commercially available toothpaste samples. The experimental parameters were optimized to achieve an optically thin and in local thermo dynamic equilibrium plasma. This improved the limits of detection of fluoride present in tooth paste samples. The strong atomic transition line of fluorine at 731.102 nm was used as the marker line to quantify the fluoride concentration levels. Our LIBS system was able to detect fluoride concentration levels in the range of 1300-1750 ppm with a detection limit of 156 ppm.

  16. Electrostatic attraction between neutral microdroplets by ion fluctuations

    Science.gov (United States)

    Sheng, Yu-Jane; Tsao, Heng-Kwong

    2004-06-01

    The interaction between two aqueous droplets containing ions is investigated. The ion-fluctuation correlation gives rise to attraction between two neutral microdroplets, similar to the van der Waals interaction between neutral atoms. Electrostatic attraction consists of contributions from various induced multipole-multipole interactions, including dipole-dipole 2 r-6 , dipole-quadrupole r-8 , dipole-octupole zzz > r-10 , and quadrupole-quadrupole interactions 2 r-10 . The mean-square multipole moments are determined analytically by linear response theory. The fluctuation-driven attraction is so strong at short distance that it may dominate over the Coulomb repulsion between like-charged droplets. These theoretical results are confirmed by Monte Carlo simulations.

  17. Radiative lifetimes and transition probabilities of neutral lanthanum

    Science.gov (United States)

    Den Hartog, E. A.; Palmer, A. J.; Lawler, J. E.

    2015-08-01

    The radiative lifetimes of 72 odd-parity levels of neutral lanthanum are measured to ±5% accuracy using time-resolved laser-induced fluorescence on a slow atomic beam. The levels range in energy from 15031 to 32140 cm-1. Branching fraction measurements using Fourier-transform spectroscopy are attempted and completed for all of the 72 levels. The branching fractions, when combined with the radiative lifetimes, yield new transition probabilities for 315 lines of the first spectrum of lanthanum (La i ). This study is part of a larger body of work on the radiative properties of rare earth neutral atoms, and is motivated by research needs in lighting science and astrophysics.

  18. Efficient laser production of energetic neutral beams

    Science.gov (United States)

    Mollica, F.; Antonelli, L.; Flacco, A.; Braenzel, J.; Vauzour, B.; Folpini, G.; Birindelli, G.; Schnuerer, M.; Batani, D.; Malka, V.

    2016-03-01

    Laser-driven ion acceleration by intense, ultra-short, laser pulse has received increasing attention in recent years, and the availability of much compact and versatile ions sources motivates the study of laser-driven sources of energetic neutral atoms. We demonstrate the production of a neutral and directional beam of hydrogen and carbon atoms up to 200 keV per nucleon, with a peak flow of 2.7× {{10}13} atom s-1. Laser accelerated ions are neutralized in a pulsed, supersonic argon jet with tunable density between 1.5× {{10}17} cm-3and 6× {{10}18} cm-3. The neutralization efficiency has been measured by a time-of-flight detector for different argon densities. An optimum is found, for which complete neutralization occurs. The neutralization rate can be explained only at high areal densities (>1× {{10}17} cm-2) by single electron charge transfer processes. These results suggest a new perspective for the study of neutral production by laser and open discussion of neutralization at a lower density.

  19. On the possible eigenoscillations of neutral sheets

    International Nuclear Information System (INIS)

    A neutral sheet model with hyperbolic tangent equilibrium magnetic field and hyperbolic square secant density profiles is considered. It is shown that the equation for small oscillations takes the form of an eigenvalue oscillation problem. Computed eigenfrequencies of the geomagnetic neutral sheet were found to be in the range of the resonant frequencies of the geomagnetic plasma sheet computed by other authors

  20. Transportation Cost Inequalities for Neutral Functional SDEs

    OpenAIRE

    Bao, Jianhai; Yuan, Chenggui

    2012-01-01

    A class of functional differential equations are investigated. Using the Girsanov-transformation argument we establish the quadratic transportation cost inequalities for a class of finite-dimensional neutral functional stochastic differential equations and infinite-dimensional neutral functional stochastic partial differential equations under different metrics.

  1. 32 CFR 644.323 - Neutral language.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Neutral language. 644.323 Section 644.323 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal § 644.323 Neutral language. Wherever the words “man”, “men”, or their...

  2. Neutralizing antibodies in hepatitis C virus infection

    Institute of Scientific and Technical Information of China (English)

    Mirjam B Zeisel; Samira Fafi-Kremer; Isabel Fofana; Heidi Barth; Fran(c)oise Stoll-Keller; Michel Doffo(e)l; Thomas F Baumert

    2007-01-01

    Hepatitis C virus (HCV) is a major cause of hepatitis world-wide. The majority of infected individuals develop chronic hepatitis which can then progress to liver cirrhosis and hepatocellular carcinoma. Spontaneous viral clearance occurs in about 20%-30% of acutely infected individuals and results in resolution of infection without sequaelae. Both viral and host factors appear to play an important role for resolution of acute infection. A large body of evidence suggests that a strong, multispecific and long-lasting cellular immune response appears to be important for control of viral infection in acute hepatitis C. Due too the lack of convenient neutralization assays,the impact of neutralizing responses for control of viral infection had been less defined. In recent years, the development of robust tissue culture model systems for HCV entry and infection has finally allowed study of antibody-mediated neutralization and to gain further insights into viral targets of host neutralizing responses.In addition, detailed analysis of antibody-mediated neutralization in individual patients as well as cohorts with well defined viral isolates has enabled the study of neutralizing responses in the course of HCV infection and characterization of the impact of neutralizing antibodies for control of viral infection. This review will summarize recent progress in the understanding of the molecular mechanisms of antibody-mediated neutralization and its impact for HCV pathogenesis.(C) 2007 The WJG Press. All rights reserved.

  3. Spontaneous CP violation and neutral flavour conservation

    International Nuclear Information System (INIS)

    The conditions for one-loop stability of neutral flavour conservation in SU(2)LxU(1) models with spontaneous CP violation are analysed. In addition to previously known cases there is an essentially unique two-generation model with two Higgs doublets where neutral flavour conservation is guaranteed to all orders by a non-standard CP symmetry. (orig.)

  4. Neutralization of low energy broad ion beam

    International Nuclear Information System (INIS)

    The paper is devoted to experimental and theoretical investigation of a low energy broad ion beam space charge and current compensation and ion-beam plasma (IBP), which would be created in transport space of the beam. The beam had cylindrical symmetry. The continuous uniform and hole tube like ion beams are used in the experiments. Different channels of electron appearing have been investigated for cases of neutralization due to secondary γ-electrons from the target and by electrons from glow cathode-neutralizer with metal or dielectric target. Results of neutralizing electrons energy distributions function measurements are presented as well as dependences of electron temperature and self-consisted plasma potential vs. beam parameters, ambient gas pressure, neutralizer parameters. Role of the thermoelectrons and dependence of IBP parameters on neutralizer area, location and potential are discussed. Significant role in neutralization of spatial collisional processes has been revealed even in neutralization by thermocathode. On the base of the experimental results self-consistent theoretical model have been developed, which describes the behavior of intense ion beam passing through the neutral gas at low pressure within conductive walls. The collisionless approach is used which means absence of collisional relaxation of the beam. This theory is used to derive the plasma potential and electron temperature within the beam

  5. A quantum eraser for neutral kaons

    International Nuclear Information System (INIS)

    Full text: Entangled neutral kaon pairs are shown to be very appropriate to discuss extensions and tests of Bohr's complementarity principle through quantum marking and erasure techniques. Neutral kaons cover in a unified way not only a lot of different quantum erasure concepts of already performed experiments, moreover, they offer a new possibility through their decay property. (author)

  6. On plasma-neutral gas interaction

    International Nuclear Information System (INIS)

    The importance of plasma-neutral gas interaction layer has been emphasized by pointing out its application to a wide variety of physical phenomena. The interaction of a magnetised plasma stream penetrating a neutral gas cloud is discussed in the light of Alfven's critical velocity and Varma's threshold velocity on the ionising interaction. Interaction of a moving magnetised plasma with a stationary neutral gas has been studied and described. The device comprises of a plasma gun and an interaction region where neutral gas cloud is injected. The interaction region is provided with a transverse magnetic field of upto 1000 G. Several diagnostics deployed at the interaction region to make measurements on the macroscopic parameters of plasma and neutral gas are described. The parameters of discharge circuits are measured with high current and voltage probes. An interaction between a magnetised plasma stream and a neutral gas cloud is demonstrated. It is shown that this interaction does not have Varma's threshold on their relative velocity. The Alfven's critical velocity phenomenon is shown to depend on the integrated column neutral gas density that a plasma stream encounters while penetrating through it and not on the neutral gas density in the range of 1017-1021m-3. (auth.)

  7. Measuring the Evolvability Landscape to study Neutrality

    CERN Document Server

    Verel, Sébastien; Clergue, Manuel

    2007-01-01

    This theoretical work defines the measure of autocorrelation of evolvability in the context of neutral fitness landscape. This measure has been studied on the classical MAX-SAT problem. This work highlight a new characteristic of neutral fitness landscapes which allows to design new adapted metaheuristic.

  8. A new sampling formula for neutral biodiversity

    NARCIS (Netherlands)

    Etienne, R.S.

    2005-01-01

    The neutral model of biodiversity, proposed by Hubbell (The Unified Neutral Theory of Biodiversity and Biogeography, Princeton University Press, Princeton, NJ, 2001) to explain the diversity of functionally equivalent species, has been subject of hot debate in community ecology. Whereas Hubbell stud

  9. Geometrically focused neutral beam accelerators

    International Nuclear Information System (INIS)

    A more reliable 40 kV, 65 A power supply drain at 0.4 A/cm2, neutral-beam accelerator was developed for the Tandem Mirror Experiment (TMX). Multiple slotted aperture grids of 60% transparency are fabricated from refractory metal wires mounted to form a spherical surface. This geometrically focuses the beam by aiming individual beamlets at the center of curvature of the spherical grid (r = 3.2 m). We attain greater reliability and faster conditioning with geometrical focusing than with the previous technique of electrostatically steering beamlets to a common point. Electrostatic steering, accomplished by offsetting grid wires, is satisfactory if the offset of a beamlet is much less than the distance from the beamlet to the grids. It was found that Pierce Angle entrance grids performed better if sharper edged. A redesigned accelerator grid support structure reduced the number of ceramic-to-metal vacuum joints, and eliminated O rings between precisely aligned parts. The suppressor grid feedthrough is required to withstand a maximum voltage of 15 kV occurring during breakdown, greatly exceeding the operating voltage of 1.5 kV. Convenient fabrication and assembly techniques have been developed. Assembly of accelerators and plasma sources in a clean room appears to reduce the conditioning time. Following the successful testing of the prototype, eight 40 kV accelerators were built for TMX. Furthermore, ten 20 kV versions were built that are modifiable to 40 kV by exchanging the entrance grid

  10. Vacuum ultraviolet laser induced fluorescence on a Si atomic beam

    Science.gov (United States)

    O'Brian, T. R.; Lawler, J. E.

    1991-01-01

    A broadly applicable vacuum ultraviolet experiment is described for measuring radiative lifetimes of neutral and singly-ionized atoms in a beam environment to 5-percent accuracy using laser induced fluorescence. First results for neutral Si are reported.

  11. Tests for complete breakdown of discrete symmetry in D neutral-anti D neutral

    International Nuclear Information System (INIS)

    Implications of the conservation of probability without assuming CPT invariance, but allowing for the existence of a direct superweak (δC=2) interaction are studied for the charmed system D neutral-anti D neutral. We find that the values of the decay widths of the particles with definite mass lead to considerable simplifications in the phenomenological description of this neutral system. These simplifications do not occur in the K neutral-anti K neutral system. In particular, we obtain the expressions for the particle number per unit time, at time tau measured in the D neutral meson rest frame, arising from an initially pure beam of D neutral-mesons. By considering the anomalous part of the particle number expression, we find means of distinguishing between the various forms of discrete symmetry breakdown. (author)

  12. Rare decays of neutral π and eta

    International Nuclear Information System (INIS)

    The decays of the pseudoscalar neutral mesons π degree and eta degree have provided a test of fundamental principles. The main branch, π degree → 2γ, was investigated in the late 60's in the context of current algebra and the decay rate calculated from the singular triangle diagram is in excellent agreement with experiment. Rare leptonic decays of the neutral pseudoscalar mesons are of interest because of the information they reveal about neutral currents or other exotic interactions between leptons and quarks. The author discusses recent information on the π degree → e+e- decay

  13. Laser etching of metals in neutral salt solutions

    Science.gov (United States)

    Datta, M.; Romankiw, L. T.; Vigliotti, D. R.; von Gutfeld, R. J.

    1987-12-01

    We report new findings that relate to rapid maskless laser etching of steel and stainless steel in neutral solutions of sodium chloride, sodium nitrate, and potassium sulfate. Etch rates have been determined as a function of laser power, laser on-time, and solution concentration. The morphology of laser-etched holes obtained in these solutions was compared with holes obtained in pure water. Results indicate that some controlled melting occurs under certain laser conditions in addition to the metal dissolution process induced by the locally intense heat of the laser beam.

  14. Neutralization mechanisms in He{sup +}-Al surface collisions

    Energy Technology Data Exchange (ETDEWEB)

    Bajales, N. [Instituto de Desarrollo Tecnologico para la Industria Quimica, Consejo Nacional de Investigaciones Cientificas y Tecnicas and Universidad Nacional del Litoral Gueemes 3450 CC 91, 3000 Santa Fe (Argentina); Ferron, J. [Instituto de Desarrollo Tecnologico para la Industria Quimica, Consejo Nacional de Investigaciones Cientificas y Tecnicas and Universidad Nacional del Litoral Gueemes 3450 CC 91, 3000 Santa Fe (Argentina); Depto. de Ing. de Materiales, Facultad de Ingenieria Quimica, Consejo Nacional de Investigaciones Cientificas y Tecnicas and Universidad Nacional del Litoral Gueemes 3450 CC 91, 3000 Santa Fe (Argentina)], E-mail: jferron@intec.unl.edu.ar; Goldberg, E.C. [Instituto de Desarrollo Tecnologico para la Industria Quimica, Consejo Nacional de Investigaciones Cientificas y Tecnicas and Universidad Nacional del Litoral Gueemes 3450 CC 91, 3000 Santa Fe (Argentina); Depto. de Ing. de Materiales, Facultad de Ingenieria Quimica, Consejo Nacional de Investigaciones Cientificas y Tecnicas and Universidad Nacional del Litoral Gueemes 3450 CC 91, 3000 Santa Fe (Argentina)

    2007-10-31

    From a quantum mechanical calculation where the populations of He ground and first excited states are properly taken into account, we can identify for the first time the neutralization to the He first excited state as an operative mechanism in He{sup +}-Al surface collisions. This identification allows us to understand the presence of high energy electrons in the ion induced electron emission spectra, through the inclusion of Auger deexcitation as an electron emission source, as well as to suggest a possible cause for the disagreement still found between theory and experiments in low energy ion scattering (LEIS) for this system.

  15. Neutralization mechanisms in He+-Al surface collisions

    International Nuclear Information System (INIS)

    From a quantum mechanical calculation where the populations of He ground and first excited states are properly taken into account, we can identify for the first time the neutralization to the He first excited state as an operative mechanism in He+-Al surface collisions. This identification allows us to understand the presence of high energy electrons in the ion induced electron emission spectra, through the inclusion of Auger deexcitation as an electron emission source, as well as to suggest a possible cause for the disagreement still found between theory and experiments in low energy ion scattering (LEIS) for this system

  16. Electromagnetic triangle anomaly and neutral pion condensation in QCD vacuum

    CERN Document Server

    Cao, Gaoqing

    2015-01-01

    We study the QCD vacuum structure under the influence of an electromagnetic field with a nonzero second Lorentz invariant $I_2=\\vec{E}\\cdot{\\vec B}$. We show that the presence of $I_2$ can induce neutral pion ($\\pi^0$) condensation in the QCD vacuum through the electromagnetic triangle anomaly. Within the frameworks of chiral perturbation theory at leading small-momenta expansion as well as the Nambu--Jona-Lasinio model at leading $1/N_c$ expansion, we quantify the dependence of the $\\pi^0$ condensate on $I_2$. The stability of the $\\pi^0$-condensed vacuum against the Schwinger charged pair production due to electric field is also discussed.

  17. Numerical study of beam propagation and plasma properties in the neutralizer and the E-RID of the ITER Neutral Beam Injector

    International Nuclear Information System (INIS)

    Non-ohmic heating will be used in the experimental nuclear fusion reactor ITER to reach thermonuclear temperatures. Two heating mechanism will be implemented, i.e. microwaves resonant with ion and electron cyclotron frequencies and energetic neutral beam injection, which contributes also to the current drive. Each one of the two neutral beam injector planned for ITER will deliver 16 MW of 1 MeV D0 beam. In the injector, negative ions D− coming from a 40 A negative ion source are electrostatically accelerated to 1 MeV, and stripped of their extra electron by collision with a target gas in a structure known as the neutralizer. Residual charged particles are deflected after the neutralizer in an electrostatic ion dump (E-RID). The ionization of the deuterium buffer gas filling the neutralizer induced by the D− beam creates a rarefied plasma which is expected to efficiently screens the Coulomb repulsion of the beam. Moreover, this plasma can eventually escape from the neutralizer and move back in the accelerator, towards the accelerating grids and the negative ion source. The transport of the beam through the neutralizer and the RID and the related plasma properties were studied using a 3D electrostatic particle-in-cell code called OBI-3 (Orsay Beam Injector 3 dimensional). Particle–particle and particle–wall collisions are treated using the Monte Carlo collision approach. Simulations show that the secondary plasma effectively screens the beam space charge preventing beam transverse expansion. Plasma ions created in the neutralizer form an upstream current with a magnitude of ∼0.5% of the negative ion current. Gas breakdown leading to arc formation in the RID was not observed. Finally, results for the propagation of non-ideal beams coming from simulations of the extraction and consecutive acceleration taken from Revel et al 2013 Nucl. Fusion 53 073027 are presented. (paper)

  18. Neutral Supersymmetric Higgs Boson Searches

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Stephen Luke; /Imperial Coll., London

    2009-09-01

    In some Supersymmetric extensions of the Standard Model, including the Minimal Supersymmetric Standard Model (MSSM), the coupling of Higgs bosons to b-quarks is enhanced. This enhancement makes the associated production of the Higgs with b-quarks an interesting search channel for the Higgs and Supersymmetry at D0. The identification of b-quarks, both online and offline, is essential to this search effort. This thesis describes the author's involvement in the development of both types of b-tagging and in the application of these techniques to the MSSM Higgs search. Work was carried out on the Level-3 trigger b-tagging algorithms. The impact parameter (IP) b-tagger was retuned and the effects of increased instantaneous luminosity on the tagger were studied. An extension of the IP-tagger to use the z-tracking information was developed. A new b-tagger using secondary vertices was developed and commissioned. A tool was developed to allow the use of large multi-run samples for trigger studies involving b-quarks. Offline, a neural network (NN) b-tagger was trained combining the existing offline lifetime based b-tagging tools. The efficiency and fake rate of the NN b-tagger were measured in data and MC. This b-tagger was internally reviewed and certified by the Collaboration and now provides the official b-tagging for all analyses using the Run IIa dataset at D0. A search was performed for neutral MSSM Higgs bosons decaying to a b{bar b} pair and produced in association with one or more b-quarks. Limits are set on the cross-section times the branching ratio for such a process. The limits were interpreted in various MSSM scenarios. This analysis uses the NN b-tagger and was the first to use this tool. The analysis also relies on triggers using the Level-3 IP b-tagging tool described previously. A likelihood discriminant was used to improve the analysis and a neural network was developed to cross-check this technique. The result of the analysis has been submitted to PRL

  19. Neutral Supersymmetric Higgs Boson Searches

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, Stephen Luke [Imperial College, London (United Kingdom)

    2008-07-01

    In some Supersymmetric extensions of the Standard Model, including the Minimal Supersymmetric Standard Model (MSSM), the coupling of Higgs bosons to b-quarks is enhanced. This enhancement makes the associated production of the Higgs with b-quarks an interesting search channel for the Higgs and Supersymmetry at D0. The identification of b-quarks, both online and offline, is essential to this search effort. This thesis describes the author's involvement in the development of both types of b-tagging and in the application of these techniques to the MSSM Higgs search. Work was carried out on the Level-3 trigger b-tagging algorithms. The impact parameter (IP) b-tagger was retuned and the effects of increased instantaneous luminosity on the tagger were studied. An extension of the IP-tagger to use the z-tracking information was developed. A new b-tagger using secondary vertices was developed and commissioned. A tool was developed to allow the use of large multi-run samples for trigger studies involving b-quarks. Offline, a neural network (NN) b-tagger was trained combining the existing offline lifetime based b-tagging tools. The efficiency and fake rate of the NN b-tagger were measured in data and MC. This b-tagger was internally reviewed and certified by the Collaboration and now provides the official b-tagging for all analyses using the Run IIa dataset at D0. A search was performed for neutral MSSM Higgs bosons decaying to a b{bar b} pair and produced in association with one or more b-quarks. Limits are set on the cross-section times the branching ratio for such a process. The limits were interpreted in various MSSM scenarios. This analysis uses the NN b-tagger and was the first to use this tool. The analysis also relies on triggers using the Level-3 IP b-tagging tool described previously. A likelihood discriminant was used to improve the analysis and a neural network was developed to cross-check this technique. The result of the analysis has been submitted to PRL

  20. Determination of the neutral to charged current cross-section ratio for antineutrino interactions on protons

    Science.gov (United States)

    Moreels, J.; Van Doninck, W.; Alamatsaz, H.; Armenise, N.; Azemoon, T.; Bartley, J. H.; Baton, J. P.; Belusevic, R.; Bertrand, D.; Brisson, V.; Calicchio, M.; Colley, D. C.; Cooper, A. M.; Erriquez, O.; Fogli-muciaccia, M. T.; Gerbier, G.; Guy, J. G.; Jones, G. T.; Kochowski, C.; Michette, A. G.; Natali, S.; Neveu, M.; Nuzzo, S.; O'Neale, S.; Parker, M. A.; Petiau, P.; Ruggieri, F.; Sacton, J.; Sewell, S.; Tyndel, M.; Vander Velde, G.; Venus, W.; Vortuba, M. F.; BEBC TST Neutrino Collaboration

    1984-04-01

    An exposure of BEBC equipped with the hydrogen-filled TST to the overlinevμ wide band beam at the CERN SPS has been used to study overlinevμ interactions on free protons. About neutral induced interactions have been observed inside the hydrogen and separated into charged current, neutral current and neutral hadron interactions using a multivariate discriminant analysis based on the kinematics of the events. The neutral to charged current cross-section ratio has been determined to be R poverlinev = 0.33 ± 0.04 . When combined with the value of Rpv previously determined in the same experiment, the result is compatible with the prediction of the standard SU (2) × U (1) model for sin 2θW = 0.24 -0.08+0.06 and ρ = 1.07 -0.08+0.06. Fixing the parameter ρ = 1 yields sin 2θW = 0.18 ± 0.04.

  1. Five-quark model with flavour-changing neutral current and dimuon events

    International Nuclear Information System (INIS)

    The recent dimuon data seem to suggest either the necessity of flavor-changing hadronic neutral current or proliferation of quarks beyond charm or both. It is shown how a five-quark model based on simple gauge group SU(2) x U(1) x U(1)' can generate the flavor-changing, in particular the needed charm-changing, neutral current in a natural fashion. A substantial D0--D-0 mixing can be obtained to account for the ''wrong-sign'' dimuons observed in ν/sub μ/-induced reactions. Because of the role of the extra neutral boson in this model, the flavor-changing neutral current is decoupled from leptonic sectors, thus suppressing the trimuon events as experiments indicate thus far

  2. Study of ν+N→ν+N+π and isospin analysis of the hadronic neutral current

    International Nuclear Information System (INIS)

    Experimental results are presented on neutrino induced single pion production in the bubble chamber Gargamelle filled with a light propane-freon mixture and exposed to the CERN PS neutrino beam. After corrections for reinteractions in the target nuclei, the neutrino neutral current cross section and the branching ratios are determined. The isospin structure of the hadronic neutral current is analysed. The conclusions are compatible with the Weinberg-Salam theory for weak and electromagnetic interactions. The isoscalar component of the neutral current is observed at the level of two standard deviations. The charged to neutral current ratio may be intepreted with the one pion production model of Adler in the framework of the above theory

  3. Neutral gas heating in helium microplasmas

    Science.gov (United States)

    Jugroot, M.

    2009-01-01

    The present study details a self-consistent model of charged and neutral particle dynamics which is applied to atmospheric small-space (200 μm) discharges in helium. Hydrodynamic transport equations of the self-consistent and time-dependant model are described with an emphasis on the different terms involved in the close coupling among charged species, neutral species, and the electric field. Those equations are solved by two-dimensional numerical schemes for both species transport and electric field. The microplasmas are studied from an initial cloud until the stages of charged particle overamplification in small spaces, where transients are particularly important. Gas heating, neutral depletion initiation, and electric field reversal are observed, highlighting the close interaction between neutral gas and charged species in governing the evolution of the microplasma.

  4. Neutral gas heating in helium microplasmas

    International Nuclear Information System (INIS)

    The present study details a self-consistent model of charged and neutral particle dynamics which is applied to atmospheric small-space (200 μm) discharges in helium. Hydrodynamic transport equations of the self-consistent and time-dependant model are described with an emphasis on the different terms involved in the close coupling among charged species, neutral species, and the electric field. Those equations are solved by two-dimensional numerical schemes for both species transport and electric field. The microplasmas are studied from an initial cloud until the stages of charged particle overamplification in small spaces, where transients are particularly important. Gas heating, neutral depletion initiation, and electric field reversal are observed, highlighting the close interaction between neutral gas and charged species in governing the evolution of the microplasma

  5. Neutral beam production using negative ions

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, E.B. Jr.

    1978-06-14

    Techniques for producing intense negative ion beams are discussed. These beams are required for intense neutral beam development at energies greater than 150 keV. Handling, acceleration, and stripping of negative ion beams are described.

  6. Neutralized transport of high intensity beams

    International Nuclear Information System (INIS)

    The NTX experiment at the Heavy Ion Fusion Virtual National Laboratory is exploring the performance of neutralized final focus systems for high perveance heavy ion beams. A converging ion beam at the exit of the final focus magnetic system is injected into a neutralized drift section. The neutralization is provided by a metal arc source and an RF plasma source. Effects of a ''plasma plug'', where electrons are extracted from a localized plasma in the upstream end of the drift section, and are then dragged along by the ion potential, as well as the ''volumetric plasma'', where neutralization is provided by the plasma laid down along the ion path, are both studied and their relative effects on the beam spot size are compared. Comparisons with 3-D PIC code predictions will also be presented

  7. The Ethics of Evaluation Neutrality and Advocacy.

    Science.gov (United States)

    Datta, Lois-ellin

    1999-01-01

    Examines arguments for and against evaluation advocacy in terms of the American Evaluation Association's "Guiding Principles for Evaluators" and other statements on advocacy and neutrality. Suggests revision of the "Guiding Principles." (Author/SLD)

  8. Kinetics of neutralization of Po-218

    International Nuclear Information System (INIS)

    In a well-defined experimental system the neutralization of polonium-218 ions was investigated as a function of the physical and chemical properties of the controlled composition atmosphere. The mobilities of Po+ and PoO2+ are determined by combining experimental results with a computer model of the system. Three neutralization mechanisms were individually studied. The small ion recombination rate has been found to be proportional to the square root of radon concentration. The electron scavenging mechanism is responsible for the neutralization of Po+ in NO2 or H2O in nitrogen. When PoO2+ is formed, the electron transfer mechanism dominates the neutralization process. The electron is transferred to PoO2+ from molecules with lower ionization potentials. The ionization potential of PoO2+ is also determined to be 10.44 +/- 0.05 eV

  9. TFTR neutral beam injection system conceptual design

    International Nuclear Information System (INIS)

    Three subsystems are described in the following chapters: (1) Neutral Beam Injection Line; (2) Power Supplies; and (3) Controls. Each chapter contains two sections: (1) Functions and Design Requirements; this is a brief listing of the requirements of components of the subsystem. (2) Design Description; this section describes the design and cost estimates. The overall performance requirements of the neutral beam injection system are summarized. (MOW)

  10. Nitrogen-neutrality: a step towards sustainability

    International Nuclear Information System (INIS)

    We propose a novel indicator measuring one dimension of the sustainability of an entity in modern societies: Nitrogen-neutrality. N-neutrality strives to offset Nr releases an entity exerts on the environment from the release of reactive nitrogen (Nr) to the environment by reducing it and by offsetting the Nr releases elsewhere. N-neutrality also aims to increase awareness about the consequences of unintentional releases of nitrogen to the environment. N-neutrality is composed of two quantified elements: Nr released by an entity (e.g. on the basis of the N footprint) and Nr reduction from management and offset projects (N offset). It includes management strategies to reduce nitrogen losses before they occur (e.g., through energy conservation). Each of those elements faces specific challenges with regard to data availability and conceptual development. Impacts of Nr releases to the environment are manifold, and the impact profile of one unit of Nr release depends strongly on the compound released and the local susceptibility to Nr. As such, N-neutrality is more difficult to conceptualize and calculate than C-neutrality. We developed a workable conceptual framework for N-neutrality which was adapted for the 6th International Nitrogen Conference (N2013, Kampala, November 2013). Total N footprint of the surveyed meals at N2013 was 66 kg N. A total of US$ 3050 was collected from the participants and used to offset the conference’s N footprint by supporting the UN Millennium Village cluster Ruhiira in South-Western Uganda. The concept needs further development in particular to better incorporate the spatio-temporal variability of impacts and to standardize the methods to quantify the required N offset to neutralize the Nr releases impact. Criteria for compensation projects need to be sharply defined to allow the development of a market for N offset certificates. (paper)

  11. Γ-source Neutral Point Clamped Inverter

    DEFF Research Database (Denmark)

    Mo, Wei; Loh, Poh Chiang; Blaabjerg, Frede

    Transformer based Z-source inverters are recently proposed to achieve promising buck-boost capability. They have improved higher buck-boost capability, smaller size and less components count over Z-source inverters. On the other hand, neutral point clamped inverters have less switching stress and...... better output performance comparing with traditional two-level inverters. Integrating these two types of configurations can help neutral point inverters achieve enhanced votlage buck-boost capability....

  12. Negative ion formation and neutralization processes, (1)

    International Nuclear Information System (INIS)

    This review has been made preliminary for the purpose of contribute to the plasma heating by ''negative ion based neutral beam injection'' in the magnetic confinement fusion reactor. A compilation includes the survey of the general processes of negative ion formation, the data of the cross section of H- ion formation and the neutralization of H- ion, and some of new processes of H- ion formation. The data of cross section are mainly experimental, but partly include the results of theoretical calculation. (author)

  13. Economists’ Statement on Network Neutrality Policy

    OpenAIRE

    Kahn, Alfred E.; Bruce M. Owen; Mayo, John; Vernon, John; Lawrence J. White; Waverman, Leonard; Cave, Martin; Patrick A. Messerlin; Joskow, Paul L.; Cramton, Peter; Litan, Robert E.; Robert S. Pindyck; Hahn, Robert W.; Savage, Scott J; Wallsten, Scott

    2007-01-01

    Network neutrality is a policy proposal that would regulate how network providers manage and price the use of their networks. Congress has introduced several bills on network neutrality. Proposed legislation generally would mandate that Internet service providers exercise no control over the content that flows over their lines and would bar providers from charging more for preferentially faster access to the Internet. These proposals must be considered carefully in light of the underlying eco...

  14. Applications of neutral beam and rf technologies

    International Nuclear Information System (INIS)

    This presentation provides an update on the applications of neutral beams and radiofrequency (rf) power in the fusion program; highlights of the ion cyclotron heating (ICH) experiments now in progress, as well as the neutral beam experiments; and heating requirements of future devices and some of the available options. Some remarks on current drive are presented because this area of technology is one that is being considered for future devices

  15. Broome and the Intuition of Neutrality

    OpenAIRE

    Rabinowicz, Wlodek

    2009-01-01

    In “Weighing Lives” (2004) John Broome criticizes a view common to many population axiologists. This is the view that population increases with extra people leading decent lives are axiologically neutral: they make the world neither better nor worse, ceteris paribus. Broome argues that this intuition, however, attractive, cannot be sustained, for several independent reasons. I respond to his criticisms and suggest that the neutrality intuition, if correctly interpreted, can after all be defen...

  16. Nonparametric Estimation of Risk-Neutral Densities

    OpenAIRE

    Grith, Maria; Härdle, Wolfgang Karl; Schienle, Melanie

    2010-01-01

    This chapter deals with nonparametric estimation of the risk neutral density. We present three different approaches which do not require parametric functional assumptions on the underlying asset price dynamics nor on the distributional form of the risk neutral density. The first estimator is a kernel smoother of the second derivative of call prices, while the second procedure applies kernel type smoothing in the implied volatility domain. In the conceptually different third approach we assume...

  17. Nitrogen-neutrality: a step towards sustainability

    Science.gov (United States)

    Leip, Adrian; Leach, Allison; Musinguzi, Patrick; Tumwesigye, Trust; Olupot, Giregon; Tenywa, John Stephen; Mudiope, Joseph; Hutton, Olivia; Cordovil, Claudia M. d. S.; Bekunda, Mateete; Galloway, James

    2014-11-01

    We propose a novel indicator measuring one dimension of the sustainability of an entity in modern societies: Nitrogen-neutrality. N-neutrality strives to offset Nr releases an entity exerts on the environment from the release of reactive nitrogen (Nr) to the environment by reducing it and by offsetting the Nr releases elsewhere. N-neutrality also aims to increase awareness about the consequences of unintentional releases of nitrogen to the environment. N-neutrality is composed of two quantified elements: Nr released by an entity (e.g. on the basis of the N footprint) and Nr reduction from management and offset projects (N offset). It includes management strategies to reduce nitrogen losses before they occur (e.g., through energy conservation). Each of those elements faces specific challenges with regard to data availability and conceptual development. Impacts of Nr releases to the environment are manifold, and the impact profile of one unit of Nr release depends strongly on the compound released and the local susceptibility to Nr. As such, N-neutrality is more difficult to conceptualize and calculate than C-neutrality. We developed a workable conceptual framework for N-neutrality which was adapted for the 6th International Nitrogen Conference (N2013, Kampala, November 2013). Total N footprint of the surveyed meals at N2013 was 66 kg N. A total of US 3050 was collected from the participants and used to offset the conference’s N footprint by supporting the UN Millennium Village cluster Ruhiira in South-Western Uganda. The concept needs further development in particular to better incorporate the spatio-temporal variability of impacts and to standardize the methods to quantify the required N offset to neutralize the Nr releases impact. Criteria for compensation projects need to be sharply defined to allow the development of a market for N offset certificates.

  18. Extensions of the TEP neutral transport methodology

    International Nuclear Information System (INIS)

    Recent extensions of the Transmission and Escape Probability methodology and its implementation in the 2-D neutral transport code GTNEUT are presented. These extensions address the issues of anisotropy of the neutral distribution function at the interfaces and the non-uniformity of the first collision source in short mean free path regions. Comparisons with Monte Carlo for a number of model problems are discussed. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Elevated expression of protein biosynthesis genes in liver and muscle of hibernating black bears (Ursus americanus) Address for reprint requests and other correspondence: V. B. Fedorov, Inst. of Arctic Biology, Univ. of Alaska Fairbanks, Fairbanks, AK 99775 (e-mail: fnvf@uaf.edu). The costs of publication of this article were defrayed in part by the payment of page charges. The article must therefore be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

    Science.gov (United States)

    Fedorov, Vadim B.; Goropashnaya, Anna V.; Tøien, Øivind; Stewart, Nathan C.; Gracey, Andrew Y.; Chang, Celia; Qin, Shizhen; Pertea, Geo; Quackenbush, John; Showe, Louise C.; Showe, Michael K.; Boyer, Bert B.; Barnes, Brian M.

    2009-01-01

    We conducted a large-scale gene expression screen using the 3,200 cDNA probe microarray developed specifically for Ursus americanus to detect expression differences in liver and skeletal muscle that occur during winter hibernation compared with animals sampled during summer. The expression of 12 genes, including RNA binding protein motif 3 (Rbm3), that are mostly involved in protein biosynthesis, was induced during hibernation in both liver and muscle. The Gene Ontology and Gene Set Enrichment analysis consistently showed a highly significant enrichment of the protein biosynthesis category by overexpressed genes in both liver and skeletal muscle during hibernation. Coordinated induction in transcriptional level of genes involved in protein biosynthesis is a distinctive feature of the transcriptome in hibernating black bears. This finding implies induction of translation and suggests an adaptive mechanism that contributes to a unique ability to reduce muscle atrophy over prolonged periods of immobility during hibernation. Comparing expression profiles in bears to small mammalian hibernators shows a general trend during hibernation of transcriptional changes that include induction of genes involved in lipid metabolism and carbohydrate synthesis as well as depression of genes involved in the urea cycle and detoxification function in liver. PMID:19240299

  20. The Phobos neutral and ionized torus

    Science.gov (United States)

    Poppe, A. R.; Curry, S. M.; Fatemi, S.

    2016-05-01

    Charged particle sputtering, micrometeoroid impact vaporization, and photon-stimulated desorption are fundamental processes operating at airless surfaces throughout the solar system. At larger bodies, such as Earth's Moon and several of the outer planet moons, these processes generate tenuous surface-bound exospheres that have been observed by a variety of methods. Phobos and Deimos, in contrast, are too gravitationally weak to keep ejected neutrals bound and, thus, are suspected to generate neutral tori in orbit around Mars. While these tori have not yet been detected, the distribution and density of both the neutral and ionized components are of fundamental interest. We combine a neutral Monte Carlo model and a hybrid plasma model to investigate both the neutral and ionized components of the Phobos torus. We show that the spatial distribution of the neutral torus is highly dependent on each individual species (due to ionization rates that span nearly 4 orders of magnitude) and on the location of Phobos with respect to Mars. Additionally, we present the flux distribution of torus pickup ions throughout the Martian system and estimate typical pickup ion fluxes. We find that the predicted pickup ion fluxes are too low to perturb the ambient plasma, consistent with previous null detections by spacecraft around Mars.

  1. Automated Facial Coding Software Outperforms People in Recognizing Neutral Faces as Neutral from Standardized Datasets

    Directory of Open Access Journals (Sweden)

    Peter eLewinski

    2015-09-01

    Full Text Available Little is known about people’s accuracy of recognizing neutral faces as neutral. In this paper, I demonstrate the importance of knowing how well people recognize neutral faces. I contrasted human recognition scores of 100 typical, neutral front-up facial images with scores of an arguably objective judge – automated facial coding (AFC software. I hypothesized that the software would outperform humans in recognizing neutral faces because of the inherently objective nature of computer algorithms. Results confirmed this hypothesis. I provided the first-ever evidence that computer software (90% was more accurate in recognizing neutral faces than people were (59%. I posited two theoretical mechanisms, i.e. smile-as-a-baseline and false recognition of emotion, as possible explanations for my findings.

  2. The neutral losses from C{sub 60}{sup +x} by neutralization-reionization mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    McHale, K.J.; Poice, M.J.; Wesdemiotis, C. [Univ. of Akron, OH (United States)

    1994-12-31

    The most obvious shortcoming of mass spectrometry is the fact that only ions can be detected. However, since the development of neutralization-reionization mass spectrometry (NRMS), neutrals produced by unimolecular reactions in the gas phase can also be observed. One particular case where NRMS is useful is for the determination of the neutral losses from Buckminsterfullerene ions. Due to the high symmetry of Buckminsterfullerene and its very regular pattern of dissociation, as seen in the EI and collisionally activated dissociation (CAD) spectra, the problem of whether the neutrals produced from C{sub 60}{sup +x} ions are sequential C{sub 2} losses or larger C{sub 2n} (n=1,2,3,4,{hor_ellipsis}) clusters has not been solved. Here, the NRMS technique of neutral fragment reionization (N,R) is used to investigate the neutral CAD fragments from C{sub 60}{sup +x}.

  3. Expression, purification, and molecular analysis of the Necator americanus glutathione S-transferase 1 (Na-GST-1): a production process developed for a lead candidate recombinant hookworm vaccine antigen.

    Science.gov (United States)

    Goud, Gaddam Narsa; Deumic, Vehid; Gupta, Richi; Brelsford, Jill; Zhan, Bin; Gillespie, Portia; Plieskatt, Jordan L; Tsao, Eric I; Hotez, Peter J; Bottazzi, Maria Elena

    2012-06-01

    The enzyme Necator americanus glutathione S-transferase 1 (Na-GST-1) belongs to a unique Nu class of GSTs and is a lead candidate antigen in a bivalent human hookworm vaccine. Here we describe the expression of Na-GST-1 in the yeast Pichia pastoris at the 20 L manufacturing scale and its purification process performed by three chromatographic steps, comprised of a Q Sepharose XL anion exchange column, followed by a Butyl Sepharose HP hydrophobic affinity column and a Superdex 75 size-exclusion column. Approximately 1.5 g of recombinant protein was recovered at an overall process yield of 51%, with a purity grade of 98% and the absence of detectable host cell protein. By mass spectrometry the recombinant protein exhibits a mass of 23,676Da, which closely matches the predicted molecular mass of the protein. The expression and purification methods described here are suitable for further scale-up product development and for its use to design formulation processes suitable to generate a vaccine for clinical testing. PMID:22503665

  4. Modeling Neutral Densities Downstream of a Gridded Ion Thruster

    Science.gov (United States)

    Soulas, George C.

    2010-01-01

    The details of a model for determining the neutral density downstream of a gridded ion thruster are presented. An investigation of the possible sources of neutrals emanating from and surrounding a NEXT ion thruster determined that the most significant contributors to the downstream neutral density include discharge chamber neutrals escaping through the perforated grids, neutrals escaping from the neutralizer, and vacuum facility background neutrals. For the neutral flux through the grids, near- and far-field equations are presented for rigorously determining the neutral density downstream of a cylindrical aperture. These equations are integrated into a spherically-domed convex grid geometry with a hexagonal array of apertures for determining neutral densities downstream of the ion thruster grids. The neutrals escaping from an off-center neutralizer are also modeled assuming diffuse neutral emission from the neutralizer keeper orifice. Finally, the effect of the surrounding vacuum facility neutrals is included and assumed to be constant. The model is used to predict the neutral density downstream of a NEXT ion thruster with and without neutralizer flow and a vacuum facility background pressure. The impacts of past simplifying assumptions for predicting downstream neutral densities are also examined for a NEXT ion thruster.

  5. The neutral sphingomyelinase-2 is involved in angiogenic signaling triggered by oxidized LDL.

    Science.gov (United States)

    Camaré, Caroline; Augé, Nathalie; Pucelle, Mélanie; Saint-Lebes, Bertrand; Grazide, Marie-Hélène; Nègre-Salvayre, Anne; Salvayre, Robert

    2016-04-01

    Capillaries of the external part of the normal arterial wall constitute the vasa vasorum network. In atherosclerotic lesions, neovascularization occurs in areas of intimal hyperplasia where it may promote plaque expansion, and intraplaque hemorrhage. Oxidized LDL that are present in atherosclerotic areas activate various angiogenic signaling pathways, including reactive oxygen species and the sphingosine kinase/sphingosine-1-phosphate pathway. We aimed to investigate whether oxidized LDL-induced angiogenesis requires neutral sphingomyelinase-2 activation and the neutral sphingomyelinase-2/sphingosine kinase-1 pathway. The role of neutral sphingomyelinase-2 in angiogenic signaling was investigated in Human Microvascular Endothelial Cells (HMEC-1) forming capillary tube on Matrigel and in vivo in the Matrigel plug assay in C57BL/6 mice and in the chicken chorioallantoic membrane model. Low concentration of human oxidized LDL elicits HMEC-1 capillary tube formation and neutral sphingomyelinase-2 activation, which were blocked by neutral sphingomyelinase-2 inhibitors, GW4869 and specific siRNA. This angiogenic effect was mimicked by low concentration of C6-Ceramide and was inhibited by sphingosine kinase-1 inhibitors. Upstream of neutral sphingomyelinase-2, oxidized LDL-induced activation required LOX-1, reactive oxygen species generation by NADPH oxidase and p38-MAPK activation. Inhibition of sphingosine kinase-1 blocked the angiogenic response and triggered HMEC-1 apoptosis. Low concentration of oxidized LDL was angiogenic in vivo, both in the Matrigel plug assay in mice and in the chorioallantoic membrane model, and was blocked by GW4869. In conclusion, low oxLDL concentration triggers sprouting angiogenesis that involves ROS-induced activation of the neutral sphingomyelinase-2/sphingosine kinase-1 pathway, and is effectively inhibited by GW4869. PMID:26855418

  6. Influence of background neutrals on charge exchange neutral spectra in ohmically heated JT-60 plasmas

    International Nuclear Information System (INIS)

    Neutrals emitted from ohmically heated JT-60 plasmas were measured by two neutral particle analysers with different sight-lines. Measured charge exchange spectra presented clear distortion arising from poloidal asymmetry of neutral sources. Ion temperature from charge exchange measurements was 10 - 30 % less than the central temperature at n-bare = (0.5 - 4.0) x 1019 m-3. From the magnitude of the spectra, we determined the neutral density in the core region. At n-bare 19 m-3, the obtained neutral density n0 decreased as n-bare increased, and agreed with the neutral density expected by electron-ion recombination alone at n-bare = (2.5 - 4.0) x 1019 m-3. The result indicates that the neutral density in the core region is determined by penetration of cold neutrals and their generations at n-bare 19 m-3, and also shows that at n-bare > approx 2.5 x 1019 m-3 the neutrals are mainly generated by recombination of protons and electrons. (author)

  7. Trilinear Neutral Gauge Boson Couplings in Effective Theories

    CERN Document Server

    Larios, F; Tavares-Velasco, G; Toscano, J J

    2001-01-01

    We list all the lowest dimension effective operators inducing off-shell trilinear neutral gauge boson couplings Z-Z-Photon, Z-Photon-Photon, and ZZZ within the effective Lagrangian approach, both in the linear and nonlinear realizations of the SU(2)_{L} X U(1)_Y gauge symmetry. In the linear scenario we find that these couplings can be generated only by dimension eight operators necessarily including the Higgs boson field, whereas in the nonlinear case they are induced by dimension six operators. We consider the impact of these couplings on some precision measurements such as the magnetic and electric dipole moments of fermions, as well as the Z boson rare decay Z -> neutrino+antineutrino+ photon. If the underlying new physics is of a decoupling nature, it is not expected that trilinear neutral gauge boson couplings may affect considerably any of these observables. On the contrary, it is just in the nonlinear scenario where these couplings have the more promising prospects of being perceptible through high pr...

  8. Trilinear neutral gauge boson couplings in effective theories

    Science.gov (United States)

    Larios, F.; Pérez, M. A.; Tavares-Velasco, G.; Toscano, J. J.

    2001-06-01

    We list all the lowest dimension effective operators inducing off-shell trilinear neutral gauge boson couplings ZZγ, Zγγ, and ZZZ within the effective Lagrangian approach, both in the linear and nonlinear realizations of SU(2)L × U(1)Y gauge symmetry. In the linear scenario we find that these couplings can be generated only by dimension-8 operators necessarily including the Higgs boson field, whereas in the nonlinear case they are induced by dimension-6 operators. We consider the impact of these couplings on some precision measurements such as the magnetic and electric dipole moments of fermions, as well as the Z boson rare decay Z-->νν¯γ. If the underlying new physics is of a decoupling nature, it is not expected that trilinear neutral gauge boson couplings may affect considerably any of these observables. On the contrary, it is just in the nonlinear scenario where these couplings have the more promising prospects of being perceptible through high precision experiments.

  9. Genetic engineering of platelets to neutralize circulating tumor cells.

    Science.gov (United States)

    Li, Jiahe; Sharkey, Charles C; Wun, Brittany; Liesveld, Jane L; King, Michael R

    2016-04-28

    Mounting experimental evidence demonstrates that platelets support cancer metastasis. Within the circulatory system, platelets guard circulating tumor cells (CTCs) from immune elimination and promote their arrest at the endothelium, supporting CTC extravasation into secondary sites. Neutralization of CTCs in blood circulation can potentially attenuate metastases to distant organs. Therefore, extensive studies have explored the blockade of platelet-CTC interactions as an anti-metastatic strategy. Such an intervention approach, however, may cause bleeding disorders since the platelet-CTC interactions inherently rely on the blood coagulation cascade including platelet activation. On the other hand, platelets have been genetically engineered to correct inherited bleeding disorders in both animal models and human clinical trials. In this study, inspired by the physical association between platelets and CTCs, platelets were genetically modified to express surface-bound tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a cytokine known to induce apoptosis specifically in tumor cells. The TRAIL-expressing platelets were demonstrated to kill cancer cells in vitro and significantly reduce metastases in a mouse model of prostate cancer metastasis. Our results suggest that using platelets to produce and deliver cancer-specific therapeutics can provide a Trojan-horse strategy of neutralizing CTCs to attenuate metastasis. PMID:26921521

  10. Association of Neutralization Sensitivity of HIV- 1 Primary Isolates With Biological Properties of Isolates From HIV-1 Infected Chinese Individuals

    Institute of Scientific and Technical Information of China (English)

    FA-XIN HEI; HAI-LI TANG; KUN-XUE HONG; JIAN-PING CHEN; HONG PENG; LIN YUAN; JIANG-QING XU; YI-MING SHAO

    2005-01-01

    Objective Although HIV-1 infection is prevalent in many regions in China, it remains largely unknown on the biological characteristics of dominant circulating isolates. This study was designed to isolate the circulating viral strains from different prevalent regions and to characterize their biological properties and neutralization sensitivity. Methods Primary viruses were isolated from fresh PBMCs using the traditional co-culture method and their capacity of inducing syncytium was tested in MT-2 cells. Meanwhile, their coreceptor usage was determined with two cell lines: Magi and GHOST (3) stably expressing CD4 and the chemokine receptor CCR5 or CXCR4. Furthermore, the sensitivity of these viruses to neutralization by HIV-1-infected patients' plasma which were highly active to neutralize SF33 strain, was quantified in GHOST cell-based neutralization assay. Results Six primary viral strains were isolated from 4 separated regions. Isolates LTG0213,LTG0214 and XVS032691 induced syncytia in MT-2 cells, and used CXCR4 as coreceptor. Isolates XJN0021, XJN0091, or SHXDC0041 did not induce syncytia, and used CCR5 as coreceptor. Overall neutralization sensitivity differed among four representative strains: HIV-1 XVS032691>LTG0214>XJN0091≈SHXDC0041. Conclusion The neutralization sensitivity of HIV isolates is linked with the phenotype of isolates, in which syncytium-inducing (SI) or CXCR4-tropic (X4) viruses are more easily neutralized than non-syncytium-inducing (NSI) or CCR5-tropic (R5) viruses. The genetic subtypes based on the phylogeny of env sequences are not classical neutralization serotypes.

  11. Neutral lipid accumulation at elevated temperature in conditional mutants of two microalgae species

    DEFF Research Database (Denmark)

    Yao, Shuo; Brandt, Anders Bøving; Egsgaard, Helge;

    2012-01-01

    mutants of Chlamydomonas reinhardtii and Chlorella vulgaris, nine out of fourty-one mutants in C. reinhardtii and eleven out of fifty-three mutants in C. vulgaris contained increased amounts of neutral lipids, predominantly as triacylglycerols. Upon temperature induced cell-cycle arrest, these mutants...

  12. Atypical and classical memory B cells produce Plasmodium falciparum neutralizing antibodies

    DEFF Research Database (Denmark)

    Muellenbeck, Matthias F; Ueberheide, Beatrix; Amulic, Borko;

    2013-01-01

    . We show at the single cell level that natural Pf infection induces the development of classical memory B cells (CM) and atypical memory B cells (AtM) that produce broadly neutralizing antibodies against blood stage Pf parasites. CM and AtM contribute to anti-Pf serum IgG production, but only AtM show...

  13. υ-magnetic moment effects in neutral current weak production of π0

    International Nuclear Information System (INIS)

    The neutral current weak π0 production induced by neutrino i.e. υ + p → υ → p + π0 is calculated using Δ dominance model. In this model, the pion production takes place through Δ+ excitation on proton or neutron target and subsequent decay of Δ+ to pions i.e. υ + p → υ + Δ+ → υ + p + π0

  14. Oblique non-neutral solitary Alfven modes in weakly nonlinear pair plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Verheest, Frank [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281, B-9000 Gent (Belgium); School of Physics, Howard College Campus, University of KwaZulu-Natal, Durban 4041 (South Africa); Lakhina, G S [Indian Institute of Geomagnetism, New Panvel, Navi Mumbai 410218 (India); Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2005-04-01

    The equal charge-to-mass ratio for both species in pair plasmas induces a decoupling of the linear eigenmodes between waves that are charge neutral or non-neutral, also at oblique propagation with respect to a static magnetic field. While the charge-neutral linear modes have been studied in greater detail, including their weakly and strongly nonlinear counterparts, the non-neutral mode has received less attention. Here the nonlinear evolution of a solitary non-neutral mode at oblique propagation is investigated in an electron-positron plasma. Employing the framework of reductive perturbation analysis, a modified Korteweg-de Vries equation (with cubic nonlinearity) for the lowest-order wave magnetic field is obtained. In the linear approximation, the non-neutral mode has its magnetic component orthogonal to the plane spanned by the directions of wave propagation and of the static magnetic field. The linear polarization is not maintained at higher orders. The results may be relevant to the microstructure in pulsar radiation or to the subpulses.

  15. Calculation of Auger-neutralization probabilities for He{sup +}-ions in LEIS

    Energy Technology Data Exchange (ETDEWEB)

    Goebl, D., E-mail: dominik.goebl@jku.at [Institut Fuer Experimentalphysik, Abt. Atom- und Oberflaechenphysik, Johannes Kepler Universitaet, A-4040 Linz (Austria); Monreal, R.C.; Valdes, D.; Primetzhofer, D. [Departamento de Fisica Teorica de la Materia Condensada, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Bauer, P. [Institut Fuer Experimentalphysik, Abt. Atom- und Oberflaechenphysik, Johannes Kepler Universitaet, A-4040 Linz (Austria)

    2011-06-01

    In Low Energy Ion Scattering (LEIS), Auger-neutralization is an omnipresent charge exchange mechanism, especially when noble gas ions are used as projectiles, with a primary energy below the threshold energy, E{sub th}, for collision induced charge exchange processes (neutralization and reionization). Recent experiments revealed a significant dependence of the ion survival probability, P{sup +}, on the crystal plane, when He{sup +} ions are scattered from a metal surface. This is in contrast to the fact, that the neutralization probability in LEIS is usually assumed to be independent of the chemical environment of the collision partner (absence of matrix effects). In order to investigate this crystal effect, an existent theory on Auger-neutralization (based on a Linear Combination of Atomic Orbitals) is adapted to the LEIS geometry. With this model, Auger-neutralization rates are calculated for a Ag(1 1 0) surface. Trajectories for He particles scattered from this surface into different azimuth directions are obtained by means of Molecular Dynamics simulations. Subsequently, the ion survival probability is calculated and compared to measurements. Good agreement is obtained which gives confidence in the applicability of this model in the LEIS regime. Moreover, it was possible to obtain detailed information on the properties of the neutralization process.

  16. Determination of the neutral to charged current cross-section ratio for antineutrino interactions on protons

    International Nuclear Information System (INIS)

    An exposure of BEBC equipped with the hydrogen-filled TST to the anti νsub(μ) wide band beam at the CERN SPS has been used to study anti νsub(μ) interactions on free protons. About 700 neutral induced interactions on free protons. About 700 neutral induced interactions have been observed inside the hydrogen and separated into charged current, neutral current and neutral hadron interactions using a multivariate discriminant analysis based on the kinematics of the events. The neutral to charged current cross-section ratio has been determined to be Rsub(p)anti ν = 0.33 +- 0.04. When combined with the value of Rsub(p)sup(ν) previously determined in the same experiment, the result is compatible with the prediction of the standard SU(2) X U(1) model for sin2thetasub(W) = 0.24sub(-0.08)sup(+0.06) and rho = 1.07sub(-0.08)sup(+0.06). Fixing the parameter rho = 1 yields sin2thetasub(W) = 0.18 +- 0.04. (orig.)

  17. Evidence for neutral-current diffractive neutral pion production from hydrogen in neutrino interactions on hydrocarbon

    CERN Document Server

    Wolcott, J; Altinok, O; Bercellie, A; Betancourt, M; Bodek, A; Bravar, A; Budd, H; Cai, T; Carneiro, M F; Chvojka, J; Devan, J; Dytman, S A; Diaz, G A; Eberly, B; Endress, E; Felix, J; Fields, L; Galindo, R; Gallagher, H; Golan, T; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kiveni, M; Kleykamp, J; Kordosky, M; Le, T; Maher, E; Manly, S; Mann, W A; Marshall, C M; Caicedo, D A Martinez; McFarland, K S; McGivern, C L; McGowan, A M; Messerly, B; Miller, J; Mislivec, A; Morfin, J G; Mousseau, J; Naples, D; Nelson, J K; Norrick, A; Nuruzzaman,; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Rakotondravohitra, L; Ramirez, M A; Ray, H; Ren, L; Rimal, D; Rodrigues, P A; Ruterbories, D; Schellman, H; Schmitz, D W; Salinas, C J Solano; Sanchez, S F; Tagg, N; Tice, B G; Valencia, E; Walton, T; Wospakrik, M; Zhang, D

    2016-01-01

    The MINERvA experiment observes an excess of events containing electromagnetic showers relative to the expectation from Monte Carlo simulations in neutral-current neutrino interactions with mean beam energy of 4.5 GeV on a hydrocarbon target. The excess is characterized and found to be consistent with neutral-current neutral pion production with a broad energy distribution peaking at 7 GeV and a total cross section of 0.26 +- 0.02 (stat) +- 0.08 (sys) x 10^{-39} cm^{2}. The angular distribution, electromagnetic shower energy, and spatial distribution of the energy depositions of the excess are consistent with expectations from neutrino neutral-current diffractive neutral pion production from hydrogen in the hydrocarbon target. These data comprise the first direct experimental observation and constraint for a reaction that poses an important background process in neutrino oscillation experiments searching for muon neutrino to electron neutrino oscillations.

  18. The Framing of Network Neutrality Governance

    DEFF Research Database (Denmark)

    Perry, James

    The neutrality of the internet with regard to applications (e.g. search, social networking, email, to mention only three) has been central to innovation and growth in the knowledge-economy over the past two decades. Until recently, neutrality was built into the internet's design via its core...... from the internet, but also whether it remains an open platform for future growth and innovation. This paper examines the interaction between the key professions driving Network Neutrality policymaking, namely Lawyers, Economists and Engineers. Combining a mapping of their observable policy inputs...... standard, Internet Protocol (IP), which rendered obsolete many of the "normal" restrictive business practises deployed by dominant telecoms companies. As both legal scholars and technologists have explained, the engineering "purity" of IP made the internet a platform for development that was truly...

  19. Neutral fermions in superstring E6-model

    International Nuclear Information System (INIS)

    The mass spectrum of neutral fermion has been studied within the framework of the superstring inspired E6-model. The subgroup SU3CxSU2RxUL(1)xUR(1) is contained in E6 is considered as an intermediate gauge group surviving after flux breaking. At the intermediate energy scale ∼1011 GeV it is spontaneously broken. The obtained mass matrix is consistent with weak universality and allows existence of a light, possibly massless, Majorana neutrino and an additional neutral lepton in the spectrum. The mass of the lepton can be in the region of quark masses

  20. Greenhouse gas neutral Germany in 2050

    International Nuclear Information System (INIS)

    In order to answer the question how a greenhouse gas neutral Germany would look like an interdisciplinary process was started by the Federal Environmental Agency. It was clear from the beginning of this work that a sustainable regenerative energy supply could not be sufficient. Therefore all relevant emission sources were included into the studies: traffic, industry, waste and waste water, agriculture, land usage, land usage changes and forestry. The necessary transformation paths to reach the aim of a greenhouse gas neutral Germany in 2050, economic considerations and political instruments were not part of this study.

  1. Carbon-neutral fuels and energy carriers

    CERN Document Server

    Muradov, Nazim Z

    2011-01-01

    Concerns over an unstable energy supply and the adverse environmental impact of carbonaceous fuels have triggered considerable efforts worldwide to find carbon-free or low-carbon alternatives to conventional fossil fuels. Carbon-Neutral Fuels and Energy Carriers emphasizes the vital role of carbon-neutral energy sources, transportation fuels, and associated technologies for establishing a sustainable energy future. Each chapter draws on the insight of world-renowned experts in such diverse fields as photochemistry and electrochemistry, solar and nuclear energy, biofuels and synthetic fuels, ca

  2. Apparatus for neutralization of accelerated ions

    Science.gov (United States)

    Fink, Joel H.; Frank, Alan M.

    1979-01-01

    Apparatus for neutralization of a beam of accelerated ions, such as hydrogen negative ions (H.sup.-), using relatively efficient strip diode lasers which emit monochromatically at an appropriate wavelength (.lambda. = 8000 A for H.sup.- ions) to strip the excess electrons by photodetachment. A cavity, formed by two or more reflectors spaced apart, causes the laser beams to undergo multiple reflections within the cavity, thus increasing the efficiency and reducing the illumination required to obtain an acceptable percentage (.about. 85%) of neutralization.

  3. Direct CP violation in neutral kaon decays

    Indian Academy of Sciences (India)

    Wojciech Wiślicki

    2004-03-01

    The final result of the NA48 experiment is presented and performed at the CERN SPS neutral kaon beams, on the direct CP violation parameter Re$('/)$, as measured from the decay rates of neutral kaons into two pions. The data collected in the years 1997-2001 yield the evidence for the direct CP violation with Re$('/)=(14.7± 2.2)× 10^{-4}$. Description of experimental method and systematics, comparison with the corresponding FNAL result and discussion of some implications for the theory are given.

  4. Shock acceleration in partially neutral plasmas

    OpenAIRE

    Morlino, G.; Amato, E.; P. Blasi(INAF Arcetri); Caprioli, D.

    2010-01-01

    We present the non-linear theory of shock acceleration applied to SNRs expanding into partially neutral plasma. Using this theory we show how the Balmer lines detected from young SNRs can be used to test the efficiency of shocks in the production of cosmic rays. In particular we investigate the effect of charge-exchange between protons and neutral hydrogen occurring in the precursor formed ahead of the shock. In this precursor the CR pressure accelerate the ionized component of the plasma and...

  5. Autologous HIV-1 neutralizing antibodies: emergence of neutralization-resistant escape virus and subsequent development of escape virus neutralizing antibodies

    DEFF Research Database (Denmark)

    Arendrup, M; Nielsen, C; Hansen, J E;

    1992-01-01

    The capacity of consecutive human sera to neutralize sequentially obtained autologous virus isolates was studied. HIV-1 was isolated three times over a 48-164-week period from three individuals immediately after seroconversion and from two individuals in later stages of infection. Development of ...

  6. Magnetospheric imaging with low-energy neutral atoms.

    OpenAIRE

    1991-01-01

    Global imaging of the magnetospheric charged particle population can be achieved by remote measurement of the neutral atoms produced when magnetospheric ions undergo charge exchange with cold exospheric neutral atoms. Previously suggested energetic neutral atom imagers were only able to measure neutral atoms with energies typically greater than several tens of keV. A laboratory prototype has been built and tested for a different type of space plasma neutral imaging instrument, which allows ne...

  7. Charged-Current Neutral Pion production at SciBooNE

    OpenAIRE

    Catala-Perez, J.

    2009-01-01

    SciBooNE, located in the Booster Neutrino Beam at Fermilab, collected data from June 2007 to August 2008 to accurately measure muon neutrino and anti-neutrino cross sections on carbon below 1 GeV neutrino energy. SciBooNE is studying charged current interactions. Among them, neutral pion production interactions will be the focus of this poster. The experimental signature of neutrino-induced neutral pion production is constituted by two electromagnetic cascades initiated by the conversion of t...

  8. Neutralization escape mutants define a dominant immunogenic neutralization site on hepatitis A virus

    International Nuclear Information System (INIS)

    Hepatitis A virus is an hepatotrophic human picornavirus which demonstrates little antigenic variability. To topologically map immunogenic sites on hepatitis A virus which elicit neutralizing antibodies, eight neutralizing monoclonal antibodies were evaluated in competition immunoassays employing radiolabeled monoclonal antibodies and HM-175 virus. Whereas two antibodies (K3-4C8 and K3-2F2) bound to intimately overlapping epitopes, the epitope bound by a third antibody (B5-B3) was distinctly different as evidenced by a lack of competition between antibodies for binding to the virus. The other five antibodies variably blocked the binding of both K3-4C8-K3-2F2 and B5-B3, suggesting that these epitopes are closely spaced and perhaps part of a single neutralization immunogenic site. Several combinations of monoclonal antibodies blocked the binding of polyclonal human convalescent antibody by greater than 96%, indicating that the neutralization epitopes bound by these antibodies are immunodominant in humans. Spontaneously arising HM-175 mutants were selected for resistance to monoclonal antibody-mediated neutralization. Neutralization resistance was associated with reduced antibody binding. These results suggest that hepatitis A virus may differ from poliovirus in possessing a single, dominant neutralization immunogenic site and therefore may be a better candidate for synthetic peptide or antiidiotype vaccine development

  9. Spatial calibration of a tokamak neutral beam diagnostic using in situ neutral beam emission.

    Science.gov (United States)

    Chrystal, C; Burrell, K H; Grierson, B A; Pace, D C

    2015-10-01

    Neutral beam injection is used in tokamaks to heat, apply torque, drive non-inductive current, and diagnose plasmas. Neutral beam diagnostics need accurate spatial calibrations to benefit from the measurement localization provided by the neutral beam. A new technique has been developed that uses in situ measurements of neutral beam emission to determine the spatial location of the beam and the associated diagnostic views. This technique was developed to improve the charge exchange recombination (CER) diagnostic at the DIII-D tokamak and uses measurements of the Doppler shift and Stark splitting of neutral beam emission made by that diagnostic. These measurements contain information about the geometric relation between the diagnostic views and the neutral beams when they are injecting power. This information is combined with standard spatial calibration measurements to create an integrated spatial calibration that provides a more complete description of the neutral beam-CER system. The integrated spatial calibration results are very similar to the standard calibration results and derived quantities from CER measurements are unchanged within their measurement errors. The methods developed to perform the integrated spatial calibration could be useful for tokamaks with limited physical access. PMID:26520957

  10. Spatial calibration of a tokamak neutral beam diagnostic using in situ neutral beam emission

    Energy Technology Data Exchange (ETDEWEB)

    Chrystal, C. [Oak Ridge Associated Universities, Oak Ridge, Tennessee 37831 (United States); Burrell, K. H.; Pace, D. C. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Grierson, B. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543-0451 (United States)

    2015-10-15

    Neutral beam injection is used in tokamaks to heat, apply torque, drive non-inductive current, and diagnose plasmas. Neutral beam diagnostics need accurate spatial calibrations to benefit from the measurement localization provided by the neutral beam. A new technique has been developed that uses in situ measurements of neutral beam emission to determine the spatial location of the beam and the associated diagnostic views. This technique was developed to improve the charge exchange recombination (CER) diagnostic at the DIII-D tokamak and uses measurements of the Doppler shift and Stark splitting of neutral beam emission made by that diagnostic. These measurements contain information about the geometric relation between the diagnostic views and the neutral beams when they are injecting power. This information is combined with standard spatial calibration measurements to create an integrated spatial calibration that provides a more complete description of the neutral beam-CER system. The integrated spatial calibration results are very similar to the standard calibration results and derived quantities from CER measurements are unchanged within their measurement errors. The methods developed to perform the integrated spatial calibration could be useful for tokamaks with limited physical access.

  11. Neutralization of rainwater acidity at Kanpur, India

    Science.gov (United States)

    Shukla, Sheo Prasad; Sharma, Mukesh

    2010-07-01

    Particulate matter (PM) levels show significant seasonal variability and this can influence the neutralization of rainwater acidity. Months were grouped in two periods: monsoon (July to October) and non-monsoon (November to June) for studying the seasonal variability in PM and rainwater composition. To clearly establish the cause effect relationship of acid rain neutralization, a two tier model was proposed involving source apportionment of particulates at two levels: (i) ambient air and (ii) rainwater particulate interaction. For modelling purpose, PM10 (n = 100), soil (n = 4) and rainwater (n = 83) samples were collected at Kanpur, India during 2000-2002. The collected samples were analysed for metals and water soluble ion composition to employ factor analysis for source identification. Knowledge of statistical correlation and chemistry fundamentals were combined to estimate the sources for acid rain neutralization. NH4+ was a dominating ion responsible for neutralizing the acidity of rainwater in monsoon period and Ca2+ was dominating in non-monsoon period. Components of secondary particles (SO42- and NO3-) showed affinity with NH4+, signifying the major role that ammonia can play if present in excess of stoichiometric requirements.

  12. The LIPSS search for light neutral bosons

    Energy Technology Data Exchange (ETDEWEB)

    Andrei Afanasev; Oliver K. Baker; Kevin Beard; George Biallas; James Boyce; Minarni Minarni; Roopchan Ramdon; Michelle D. Shinn; Penny Slocum

    2009-07-01

    An overview is presented of the LIPSS experimental search for very light neutral bosons using laser light from Jefferson Lab's Free Electron Laser. This facility provides very high power beams of photons over a large optical range, particularly at infrared wavelengths. Data has been collected in several experimental runs during the course of the past three years, most recently in the Fall of 2009.

  13. Development of KSTAR Neutral Beam Heating System

    Energy Technology Data Exchange (ETDEWEB)

    Oh, B. H.; Song, W. S.; Yoon, B. J. (and others)

    2007-10-15

    The prototype components of a neutral beam injection (NBI) system have been developed for the KSTAR, and a capability of the manufactured components has been tested. High power ion source, acceleration power supply, other ion source power supplies, neutralizer, bending magnet for ion beam separation, calorimeter, and cryo-sorption pump have been developed by using the domestic technologies and tested for a neutral beam injection of 8 MW per beamline with a pulse duration of 300 seconds. The developed components have been continuously upgraded to achieve the design requirements. The development technology of high power and long pulse neutral beam injection system has been proved with the achievement of 5.2 MW output for a short pulse length and 1.6 MW output for a pulse length of 300 seconds. Using these development technologies, the domestic NB technology has been stabilized under the development of high power ion source, NB beamline components, high voltage and current power supplies, NB diagnostics, NB system operation and control.

  14. Toxic emissions and devalued CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...

  15. Doublet III vacuum vessel neutral beam armor

    International Nuclear Information System (INIS)

    The evolution of the Doublet III neutral beam armor is followed from the initial design of a radiation cooled metallic tile to the present actively cooled graphite design. Results of the thermal and stress analyses that dictated the present design are reviewed

  16. Neutral beam data systems at ORNL

    International Nuclear Information System (INIS)

    A control system for neutral injection beam lines has been designed, implemented, and used with much success. Despite the problems with very high power levels this system is very successful in relieving the operators burdens of slow conditioning, data recording, and mode switching. The use of computer control with multiple beam lines now appears very promising

  17. Neutron production by neutral beam sources

    Energy Technology Data Exchange (ETDEWEB)

    Berkner, K.H.; Massoletti, D.J.; McCaslin, J.B.; Pyle, R.V.; Ruby, L.

    1979-11-01

    Neutron yields, from interactions of multiampere 40- to 120-keV deuterium beams with deuterium atoms implanted in copper targets, have been measured in order to provide input data for shielding of neutral-deuterium beam facilities for magnetic fusion experiments.

  18. Neutrino emissivity under neutral kaon condensation

    OpenAIRE

    Kubis, Sebastian

    2005-01-01

    Neutrino emissivity from neutron star matter with neutral kaon condensate is considered. It is shown that a new cooling channel is opened, and what is more, all previously known channels acquire the greater emissivity reaching the level of the direct URCA cycle in normal matter.

  19. Atomic Structure Calculations for Neutral Oxygen

    OpenAIRE

    Alonizan, Norah; Qindeel, Rabia; Ben Nessib, Nabil

    2016-01-01

    Energy levels and oscillator strengths for neutral oxygen have been calculated using the Cowan (CW), SUPERSTRUCTURE (SS), and AUTOSTRUCTURE (AS) atomic structure codes. The results obtained with these atomic codes have been compared with MCHF calculations and experimental values from the National Institute of Standards and Technology (NIST) database.

  20. SODA ASH TREATMENT OF NEUTRALIZED MINE DRAINAGE

    Science.gov (United States)

    Utilization of acid mine drainage (AMD) streams as a source of potable and industrial water has become a major goal of several proposed AMD treatment schemes. From among the various schemes available, the lime neutralization/soda ash softening process was selected for use at Alto...

  1. Neutral kaons without Weisskopf-Wigner approximation

    International Nuclear Information System (INIS)

    The model-independent formalism is constructed to describe decays of mixed particles without using the Weisskopf-Wigner approximation (WWA). Limitations due to various symmetries are traced for neutral K mesons. As an application we show that effects of CPT violation and going beyond WWA may be separated and studied independently. 16 refs

  2. Neutral Kaons without Weisskopf-Wigner Approximation

    OpenAIRE

    Azimov, Ya. I.

    1995-01-01

    The model-independent formalism is constructed to describe decays of mixed particles without using the Weisskopf-Wigner approximation. Limitations due to various symmetries are traced for neutral $K-$mesons. As an application we show that effects of $CPT-$violation and going beyond WWA may be separated and studied independently.

  3. Neutral nuclear core vs super charged one

    OpenAIRE

    Rotondo, M; Ruffini, R.; Xue, S. -S.

    2008-01-01

    Based on the Thomas-Fermi approach, we describe and distinguish the electron distributions around extended nuclear cores: (i) in the case that cores are neutral for electrons bound by protons inside cores and proton and electron numbers are the same; (ii) in the case that super charged cores are bare, electrons (positrons) produced by vacuum polarization are bound by (fly into) cores (infinity).

  4. The fallacies of network neutrality regulation

    OpenAIRE

    Knieps, Günter; Zenhäusern, Patrick

    2008-01-01

    In this paper, historical functionalities of the traditional Internet are contrasted with today's Internet functionalities of the 'smart' Internet architecture. It is shown that network neutrality regulation prohibiting congestion management and traffic quality differentiation is contrary to economically founded allocation mechanisms. By access regulation of local loop bottleneck components the transfer of market power from the telecommunications infrastructure into the complementary Internet...

  5. Method of purifying neutral organophosphorus extractants

    Science.gov (United States)

    Horwitz, E. Philip; Gatrone, Ralph C.; Chiarizia, Renato

    1988-01-01

    A method for removing acidic contaminants from neutral mono and bifunctional organophosphorous extractants by contacting the extractant with a macroporous cation exchange resin in the H.sup.+ state followed by contact with a macroporous anion exchange resin in the OH.sup.- state, whereupon the resins take up the acidic contaminants from the extractant, purifying the extractant and improving its extraction capability.

  6. Variational Principle for Optimal Accelerated Neutralized Flow

    International Nuclear Information System (INIS)

    Minimizing the energy deposited in the electron current in neutralized flows, such as in the Hall thruster, is examined. Modifying the electron current along the channel by inserting emitting electrodes, can enhance the efficiency. By employing variational methods, an optimal electron current distribution is found. The efficiency enhancement due to this effect, however, is shown to be small

  7. CP Violation, Neutral Currents, and Weak Equivalence

    Science.gov (United States)

    Fitch, V. L.

    1972-03-23

    Within the past few months two excellent summaries of the state of our knowledge of the weak interactions have been presented. Correspondingly, we will not attempt a comprehensive review but instead concentrate this discussion on the status of CP violation, the question of the neutral currents, and the weak equivalence principle.

  8. On individual neutrality and collective decision making

    OpenAIRE

    Zhu, Mu; Wang, Shangsi; Xin, Lu

    2012-01-01

    We derive a simple mathematical "theory" to show that two decision-making entities can work better together only if at least one of them is occasionally willing to stay neutral. This provides a mathematical "justification" for an age-old cliche among marriage counselors.

  9. If It's Neutral, It's Not Technology

    Science.gov (United States)

    Strate, Lance

    2012-01-01

    Taking a media ecology perspective, this article argues that technology cannot be neutral, because it is a form of change, and it has an inherent bias based on the properties of its materials and methods. Additionally, the application of a technology is an intrinsic part of the technology itself, as is technique, instructions, software, or…

  10. Neutral beam injection into mirror machines

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, E.B. Jr.

    1976-08-01

    Neutral injection into 2XIIB has started and sustained a hot ion plasma of n/sub h/ = 10/sup 13/ - 10/sup 14/ cm/sup -3/ and anti E/sub i/ = 9 to 14 keV. The experiment and its interpretation are discussed.

  11. Transition radiation of ultrarelativistic neutral particles

    International Nuclear Information System (INIS)

    We perform a quantum theoretical calculation of transition radiation by neutral particles with spin 1/2 equipped with magnetic moments and/or electric dipole moments. The limit of vanishing masses is treated exactly for arbitrary refraction index. Finally we apply our result to the solar neutrino flux. (author)

  12. Compact Ion and Neutral Mass Spectrometer with Ion Drifts, Temperatures and Neutral Winds

    Science.gov (United States)

    Paschalidis, Nikolaos

    2016-07-01

    In situ measurements of atmospheric neutral and ion composition and density, temperatures, ion drifts and neutral winds, are in high demand to study the dynamics of the ionosphere-theremosphere-mesosphere system. This paper presents a compact Ion and Neutral Mass Spectrometer (INMS) with impended ion drifts and temperature, and neutral winds capability for in situ measurements of ions and neutrals H, He, N, O, N2, O2. The mass resolution M/dM is approximately 10 at an incoming energy range of 0-20eV. The goal is to resolve ion drifts in the range 0 to 3000m/sec with a resolution better than 50m/sec, and neutral winds in the range of 0 to 1000m/sec with similar resolution. For temperatures the goal is to cover a dynamic range of 0 to 5000K. The INMS is based on front end optics for ions and neutrals, pre acceleration, gated time of flight, top hat ESA, MCP detectors and compact electronics. The instrument is redundant for ions and neutrals with the ion and neutral sensor heads on opposite sides and with full electronics in the middle. The ion front end includes RPA for temperature scanning and neutral front end includes angular modulation and thermionic ionization and ion blocking grids. The electronics include fast electric gating, TOF electronics, TOF binning and C&DH digital electronics. The data package includes 400 mass bins each for ions and neutrals and key housekeeping data for instrument health and calibration. The data sampling can be commanded from 0.1 to 10 sec with 1sec nominal setting. The instrument has significant onboard storage capability and a data compression scheme. The mass spectrometer version of the instrument has been flown on the Exocube mission. The instrument occupied 1.5U volume, weighed only 560 g and required nominal power of 1.6W The ExoCube mission was designed to acquire global knowledge of in-situ densities of [H], [He], [O] and H+, He+, O+ in the upper ionosphere and lower exosphere in combination with incoherent scatter radar and

  13. Neutral kaon photoproduction at LNS, Tohoku University

    International Nuclear Information System (INIS)

    The elementary photo-strangeness production process has been intensively studied based on the high-quality data of the charged kaon channel, γ + p → K+ + Λ(Σ0). However, there had been no reliable data for the neutral kaon channel γ + n → K0 + Λ(Σ0) and the theoretical investigations suffer seriously from the lack of the data. In order to have reliable data for the neutral kaon photo-production data, substantial effort has been made to measure the γ + n → K0 + Λ process in the π+π- decay channel, using a liquid deuterium target and a tagged photon beam (Eγ = 0.8-1.1 GeV) in the threshold region at the Laboratory of Nuclear Science (LNS), Tohoku University. We have taken exploratory data quite successfully with the use of Neutral Kaon Spectrometer (NKS) at LNS-Tohoku in 2003 and 2004. The data is compared to theoretical models and it indicates a hint that the K0 differential cross section has a backward peak in the energy region. The second generation of the experiment, NKS2, is designed to extend the NKS experiment by considerably upgrading the original neutral kaon spectrometer, fully replacing the spectrometer magnet, tracking detectors and all the trigger counters. The new spectrometer NKS2 has significantly larger acceptance for neutral kaons compared with NKS, particularly covering forward angles and much better invariant mass resolution. The estimated acceptance of NKS2 is three (ten) times larger for KS0(Λ) than that of NKS. The spectrometer is newly constructed and installed at the Laboratory of Nuclear Science, Tohoku University in 2005. The deuterium target data was taken with tagged photon beam in 2006-2007. We will report recent results of NKS2 in this paper. Additionally, a status of the upgrade project that gives us larger acceptance and capability of K0 + Λ coincidence measurement will be presented. (author)

  14. Experimental Investigation of the Neutral sheet Profile During Magnetic Reconnection

    International Nuclear Information System (INIS)

    During magnetic reconnection, a ''neutral sheet'' current is induced, heating the plasma. The resultant plasma thermal pressure forms a stationary equilibrium with the opposing magnetic fields. The reconnection layer profile holds significant clues about the physical mechanisms which control reconnection. On the Magnetic Reconnection Experiment [M. Yamada et al., Phys. Plasmas 4, 1936 (1997)], a quasi steady-state and axisymmetric neutral sheet profile has been measured precisely using a magnetic probe array with spatial resolution equal to one quarter of the ion gyro-radius. It was found that the reconnecting field profile fits well with a Harris-type profile [E. G. Harris, Il Nuovo Cimento 23, 115 (1962)], B(x) approximately tanh(x/delta). This agreement is remarkable since the Harris theory does not take into account reconnection and associated electric fields and dissipation. An explanation for this agreement is presented. The sheet thickness delta is found to be approximately 0.4 times the ion skin depth, which agrees with a generalized Harris theory incorporating non-isothermal electron and ion temperatures and finite electric field. The detailed study of additional local features of the reconnection region is also presented

  15. Ion and neutral dynamics in Hall plasma accelerator ionization instabilities

    Science.gov (United States)

    Lucca Fabris, Andrea; Young, Christopher; Cappelli, Mark

    2015-09-01

    Hall thrusters, the extensively studied E × B devices used for space propulsion applications, are rife with instabilities and fluctuations. Many are thought to be fundamentally linked to microscopic processes like electron transport across magnetic field lines and propellant ionization that in turn affect macroscopic properties like device performance and lifetime. One of the strongest oscillatory regimes is the ``breathing mode,'' characterized by a propagating ionization front, time-varying ion acceleration profiles, and quasi-periodic 10-50 kHz current oscillations. Determining the temporal and spatial evolution of plasma properties is critical to achieving a fundamental physical understanding of these processes. We present non-intrusive laser-induced fluorescence measurements of the local ion and neutral velocity distribution functions synchronized with the breathing mode oscillations. Measurements reveal strong ion velocity fluctuations, multiple ion populations arising in narrow time windows throughout the near-field plume, and the periodic population and depopulation of neutral excited states. Analyzing these detailed experimental results in the context of the existing literature clarifies the fundamental physical processes underlying the breathing mode. This work is sponsored by the U.S. Air Force Office of Scientific Research with Dr. M. Birkan as program manager. C.Y. acknowledges support from the DOE NSSA Stewardship Science Graduate Fellowship under contract DE-FC52-08NA28752.

  16. Probing CPT in transitions with entangled neutral kaons

    CERN Document Server

    Bernabeu, J; Villanueva-Perez, P

    2015-01-01

    In this paper we present a novel CPT symmetry test in the neutral kaon system based, for the first time, on the direct comparison of the probabilities of a transition and its CPT reverse. The required interchange of "in" $\\leftrightarrow$ "out" states for a given process is obtained exploiting the Einstein-Podolsky-Rosen correlations of neutral kaon pairs produced at a $\\phi$-factory. The observable quantities have been constructed by selecting the two semileptonic decays for flavour tag, the $\\pi\\pi$ and $3\\pi^0$ decays for CP tag and the time orderings of the decay pairs. The interpretation in terms of the standard Weisskopf-Wigner approach to this system, directly connects CPT violation in these observables to the violating $\\Re\\delta$ parameter in the mass matrix of $K^0$-$\\bar{K^0}$, a genuine CPT violating effect independent of $\\Delta \\Gamma$ and not requiring the decay as an essential ingredient. Possible spurious effects induced by CP violation in the decay and/or a violation of the $\\Delta S= \\Delta...

  17. Maturation Pathways of Cross-Reactive HIV-1 Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Dimiter S. Dimitrov

    2009-11-01

    Full Text Available Several human monoclonal antibodies (hmAbs and antibody fragments, including the best characterized in terms of structure-function b12 and Fab X5, exhibit relatively potent and broad HIV-1 neutralizing activity. However, the elicitation of b12 or b12-like antibodies in vivo by vaccine immunogens based on the HIV-1 envelope glycoprotein (Env has not been successful. B12 is highly divergent from the closest corresponding germline antibody while X5 is less divergent. We have hypothesized that the relatively high degree of specific somatic hypermutations may preclude binding of the HIV-1 envelope glycoprotein (Env to closest germline antibodies, and that identifying antibodies that are intermediates in the pathways to maturation could help design novel vaccine immunogens to guide the immune system for their enhanced elicitation. In support of this hypothesis we have previously found that a germline-like b12 (monovalent and bivalent scFv as an Fc fusion protein or IgG lacks measurable binding to an Env as measured by ELISA with a sensitivity in the μM range [1]; here we present evidence confirming and expanding these findings for a panel of Envs. In contrast, a germline-like scFv X5 bound Env with high (nM affinity. To begin to explore the maturation pathways of these antibodies we identified several possible b12 intermediate antibodies and tested their neutralizing activity. These intermediate antibodies neutralized only some HIV-1 isolates and with relatively weak potency. In contrast, germline-like scFv X5 neutralized a subset of the tested HIV-1 isolates with comparable efficiencies to that of the mature X5. These results could help explain the relatively high immunogenicity of the coreceptor binding site on gp120 and the abundance of CD4-induced (CD4i antibodies in HIV-1-infected patients (X5 is a CD4i antibody as well as the maturation pathway of X5. They also can help identify antigens that can bind specifically to b12 germline and

  18. Single top production associated with a neutral scalar at LHC in topcolor-assisted technicolor

    Institute of Scientific and Technical Information of China (English)

    LIU Guo-Li; ZHANG Huan-Jun

    2008-01-01

    The topcolor-assisted technicolor(TC2)model predicts a number of neutral SCalars like the top-pion (π0t)and the top-Higgs(h0t).These scalar8 have flavor-changing neutral-current(FCNC)top quark couphngs,among which the top-charm transition couplings may be sizable.Such FCNC couplings induce single top productions associated with a neutral scalar at the CERN Large Hadron Collider(LHC)through the parton processes cg→tπ0t and cg→th0t.In this paper we examine these productions and find their production rates can exceed the 3σ sensitivity of the LHC in a large part of parameter space.Since in the Standard Model and the minimal supersymmetric model such rare productions have unobservably small production rates at the LHC.these rare processes will serve as a good probe for the TC2 model.

  19. Antibody-Mediated Neutralization of the Exotoxin Mycolactone, the Main Virulence Factor Produced by Mycobacterium ulcerans.

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Dangy

    2016-06-01

    Full Text Available Mycolactone, the macrolide exotoxin produced by Mycobacterium ulcerans, causes extensive tissue destruction by inducing apoptosis of host cells. In this study, we aimed at the production of antibodies that could neutralize the cytotoxic activities of mycolactone.Using the B cell hybridoma technology, we generated a series of monoclonal antibodies with specificity for mycolactone from spleen cells of mice immunized with the protein conjugate of a truncated synthetic mycolactone derivative. L929 fibroblasts were used as a model system to investigate whether these antibodies can inhibit the biological effects of mycolactone. By measuring the metabolic activity of the fibroblasts, we found that anti-mycolactone mAbs can completely neutralize the cytotoxic activity of mycolactone.The toxin neutralizing capacity of anti-mycolactone mAbs supports the concept of evaluating the macrolide toxin as vaccine target.

  20. Probing new physics in charm couplings with flavor-changing neutral currents

    International Nuclear Information System (INIS)

    Low-energy experiments involving kaon, B-meson, D-meson, and hyperon flavor-changing neutral transitions have confirmed the loop-induced flavor-changing neutral current picture of the standard model. The continuing study of these processes is essential to further refine this picture and ultimately understand the flavor dynamics. In this paper we consider deviations from the standard model in the charm sector and their effect on flavor-changing neutral current processes. Specifically, we parametrize new physics in terms of left- and right-handed anomalous couplings of the W boson to the charm quark. We present a comprehensive study of existing constraints and point out those measurements that are most sensitive to new physics of this type.

  1. Electron extraction mechanisms of a micro-ECR neutralizer

    Science.gov (United States)

    Takao, Yoshinori; Hiramoto, Kenta; Nakagawa, Yuichi; Kasagi, Yusuke; Koizumi, Hiroyuki; Komurasaki, Kimiya

    2016-07-01

    Three-dimensional particle simulations have been conducted to analyze the mechanisms of electron extraction through the orifices of a 4.2 GHz microwave discharge microneutralizer, using a xenon electron cyclotron resonance plasma. The dimensions of the neutralizer are 20 × 20 × 4 mm3, and a ring-shaped microwave antenna and permanent magnets are employed for its discharges. The numerical model is composed of a particle-in-cell simulation with a Monte Carlo collision algorithm for charged particle motions, a finite-difference time-domain method for microwaves, and a finite element analysis for magnetostatic fields. The simulation results have shown that the electrostatic field inside the plasma source has a dominant effect on electron extraction. The extracted electrons move along the magnetic field line to the orifice entrances and the E × B drift at the orifice edge induces electron extraction.

  2. Intrinsic CPT violation and decoherence for entangled neutral mesons

    CERN Document Server

    Bernabeu, J; Papavassiliou, J; Waldron-Lauda, A

    2006-01-01

    We present a combined treatment of quantum-gravity-induced effects and intrinsic CPT violation in entangled neutral-Kaon states. Our analysis takes into consideration two types of effects: first, those associated with the loss of particle-antiparticle identity, as a result of the ill-defined nature of the CPT operator, and second, effects due to the non-unitary evolution of the Kaons in the space-time foam. By studying a variety of phi-factory observables, involving identical as well as general final states, we derive analytical expressions, to leading order in the associated CPT violating parameters, for double-decay rates and their time-integrated counterparts. Our analysis shows that the various types of the aforementioned effects may be disentangled through judicious combinations of appropriate observables in a phi factory.

  3. Intrinsic CPT violation and decoherence for entangled neutral mesons

    International Nuclear Information System (INIS)

    We present a combined treatment of quantum-gravity-induced decoherence and intrinsic CPT violation in entangled neutral-kaon states. Our analysis takes into consideration two types of effects: first, those associated with the loss of particle-antiparticle identity, as a result of the ill-defined nature of the CPT operator, and second, effects due to the nonunitary evolution of the kaons in the space-time foam. By studying a variety of φ-factory observables, involving identical as well as general final states, we derive analytical expressions, to leading order in the associated CPT violating parameters, for double-decay rates and their time-integrated counterparts. Our analysis shows that the various types of the aforementioned effects may be disentangled through judicious combinations of appropriate observables in a φ factory

  4. Study of electrical resistivity and thermal conductivity into neutral plasma

    International Nuclear Information System (INIS)

    The major portion of the bulk plasma in magnetospheric space, interplanetary plasma belts and the solar winds contain neutral particles. Evidently these neutral particles undergo binary collisions with the charged particles and among themselves so as to contribute significantly to the transport and diffusion process in a singly charged electron – ion magnetoplasma. The effects of the neutral particles collisions on various diffusion transport coefficients are studied for magnetised electron-ion plasma and appropriately modified coefficients are derived analytically. The results reveal that these coefficients increase significantly owing to the effect of the charge -neutral and neutral-neutral collisions

  5. Research on Stress Neutral Layer Offset in the Straightening Process

    Directory of Open Access Journals (Sweden)

    Hailian Gui

    2015-01-01

    Full Text Available The stress neutral layer offset is analyzed by theoretical and numerical calculation methods. In traditional straightening theory, the stress neutral layer was consistent with the geometric central layer. However, there is a phenomenon that the stress neutral layer has some offset with the geometric neutral layer. This offset is a very important factor for improving the precision of the straightening force. The formula of the stress neutral layer offset is obtained by a theoretical method and the change law is given by numerical calculation method. The neutral layer offset theory provides the theoretical basis for establishing the model of straightening force precisely.

  6. The neutralization of harmony: the problem of technological neutrality, east and west

    OpenAIRE

    Thompson, M

    2011-01-01

    Technological neutrality in law is, roughly, the idea that law should not pick technological winners and losers, that law should neither help nor hinder particular types of technological artefacts. It has become a pervasive idea in technology law and politics in the West and now forces itself upon the World Trade Organization as a means of preventing China from regulating its territorial Internet. This paper examines the idea of technological neutrality for both its internal coherence and its...

  7. Increased titers of neutralizing antibodies after immunization with both envelope proteins of the porcine endogenous retroviruses (PERVs

    Directory of Open Access Journals (Sweden)

    Denner Joachim

    2012-11-01

    Full Text Available Abstract Despite enormous difficulties to induce antibodies neutralizing HIV-1, especially broadly neutralizing antibodies directed against the conserved membrane proximal external region (MPER of the transmembrane envelope protein, such antibodies can be easily induced in the case of gammaretroviruses, among them the porcine endogenous retroviruses (PERVs. In addition to neutralizing antibodies directed against the transmembrane envelope protein p15E, neutralizing antibodies were also induced by immunization with the surface envelope protein gp70. PERVs represent a special risk for xenotransplantation using pig tissues or organs since they are integrated in the genome of all pigs and infect human cells and a vaccine may protect from transmission to the recipient. To investigate the effect of simultaneous immunization with both proteins in detail, a study was performed in hamsters. Gp70 and p15E of PERV were produced in E. coli, purified and used for immunization. All animals developed binding antibodies against the antigens used for immunization. Sera from animals immunized with p15E recognized epitopes in the MPER and the fusion peptide proximal region (FPPR of p15E. One MPER epitope showed a sequence homology to an epitope in the MPER of gp41 of HIV-1 recognized by broadly neutralizing antibodies found in HIV infected individuals. Neutralizing antibodies were detected in all sera. Most importantly, sera from animals immunized with gp70 had a higher neutralizing activity when compared with the sera from animals immunized with p15E and sera from animals immunized with gp70 together with p15E had a higher neutralizing activity compared with sera from animals immunized with each antigen alone. These immunization studies are important for the development of vaccines against other retroviruses including the human immunodeficiency virus HIV-1.

  8. Neutral-fueling pressure measurements and modeling near the plasma edge in TMX-U. Revision 1

    International Nuclear Information System (INIS)

    Large variations in pressure from external gas-fueling sources and from plasma-induced wall reflux along the TMX-U plasma have been observed. These pressure variations can produce locally high neutral density in the plasma, which strongly affects the plasma parameters. These local pressure measurements include data from a newly installed neutral-pressure diagnostic system of fast magnetron gauges. The plasma-induced warm-wall reflux has been observed to be primarily HD and H2 as opposed to D2. This observation supports the model that all of the neutral D2 gas enters the plasma region, strikes the plasma first, and is dissociated. The part of the D2 gas, which is not absorbed as ions, strikes a wall, where it is converted to HD. Electron induced wall desorption measured by a mass spectroscopy and actual analysis of the Ti indicates predominately H2 instead of D2 wall loading in TMX-U

  9. Production of low-energy neutral oxygen beams by grazing-incidence neutralization

    International Nuclear Information System (INIS)

    The Vanderbilt University neutral oxygen facility produces beams of low-energy neutral oxygen atoms by means of grazing-incidence collisions between ion beams and metal surfaces. Residual ions are reflected by applied electric fields. This method can utilize initial ion beams of either O(+) or O2(+) since a very large percentage of molecular oxygen ions are dissociated when they undergo grazing-incidence neutralization. The method of neutralization is applicable to low-energy beams and to all ions. Particular emphasis is on O and N2 beams for simulation of the low Earth orbit space environment. Since the beam is a pure O-neutral beam and since measurements of the interaction of the beam with solid surfaces are made spectroscopically, absolute reaction rates can be determined. The technique permits the beams to be used in conjunction with electron and photon irradiation for studies of synergistic effects. Comparisons of optical spectra of Kapton excited by 2.5-keV O, O(+), and O2(+) show significant differences. Optical spectra of Kapton excited by neutral oxygen beams of less than 1 keV have been recorded

  10. The production of low-energy neutral oxygen beams by grazing-incidence neutralization

    Science.gov (United States)

    Albridge, R. G.; Haglund, R. F.; Tolk, N. H.; Daech, A. F.

    1987-01-01

    The Vanderbilt University neutral oxygen facility produces beams of low-energy neutral oxygen atoms by means of grazing-incidence collisions between ion beams and metal surfaces. Residual ions are reflected by applied electric fields. This method can utilize initial ion beams of either O(+) or O2(+) since a very large percentage of molecular oxygen ions are dissociated when they undergo grazing-incidence neutralization. The method of neutralization is applicable to low-energy beams and to all ions. Particular emphasis is on O and N2 beams for simulation of the low Earth orbit space environment. Since the beam is a pure O-neutral beam and since measurements of the interaction of the beam with solid surfaces are made spectroscopically, absolute reaction rates can be determined. The technique permits the beams to be used in conjunction with electron and photon irradiation for studies of synergistic effects. Comparisons of optical spectra of Kapton excited by 2.5-keV O, O(+), and O2(+) show significant differences. Optical spectra of Kapton excited by neutral oxygen beams of less than 1 keV have been recorded.

  11. Antibodies against Marinobacter algicola and Salmonella typhimurium flagellins do not cross-neutralize TLR5 activation.

    Directory of Open Access Journals (Sweden)

    Raul Terron-Exposito

    Full Text Available Flagellins evoke strong innate and adaptive immune responses. These proteins may play a key role as radioprotectors, exert antitumoral activity in certain types of tumor and reduce graft-versus-host disease in allogeneic hematopoietic stem cell transplant recipients. Notwithstanding, flagellins are highly immunogenic, and repeated use leads to their neutralization by systemic antibodies. This neutralization is not prevented by using functional deleted flagellins. These observations led us to explore the possibility of preventing initial neutralization by means of another functional flagellin that does not belong to common pathogenic bacteria but that has the capacity to activate TLR5. Here we characterized the functional capacity of the two-phase Marinobacter algicola (MA-derived flagellins (F and FR as systemic and mucosal adjuvants and compared their performance with that of Salmonella typhimurium (STF flagellins (FljB and FliC. We also report for the first time on the in vitro and in vivo capacity of various flagellins to trigger TLR5 activation in the presence of species-specific anti-flagellin antibodies, the cross-neutralization mediated by these antibodies, and the sequential use of these flagellins for TLR5 activation. Our results showed that MA flagellins behave in a similar way to STF ones, inducing pro-inflammatory cytokines (IL8, CCL20, CCL2 and evoking a strong in vivo antibody response against a model epitope. More importantly, MA flagellins were fully functional, in vitro or in vivo, in the presence of a high concentration of neutralizing anti-flagellin STF antibodies, and STF flagellin was not inhibited by neutralizing anti-flagellin MA antibodies. The use of active flagellins from distinct bacteria could be a useful approach to prevent systemic neutralization of this group of adjuvants and to facilitate the rational design of flagellin-based vaccines and/or other therapeutic treatments (against ischemia, acute renal failure

  12. Oscillatory profiles of positive, negative and neutral feedback stimuli during adaptive decision making.

    Science.gov (United States)

    Li, Peng; Baker, Travis E; Warren, Chris; Li, Hong

    2016-09-01

    The electrophysiological response to positive and negative feedback during reinforcement learning has been well documented over the past two decades, yet, little is known about the neural response to uninformative events that often follow our actions. To address this issue, we recorded the electroencephalograph (EEG) during a time-estimation task using both informative (positive and negative) and uninformative (neutral) feedback. In the time-frequency domain, uninformative feedback elicited significantly less induced beta-gamma activity than informative feedback. This result suggests that beta-gamma activity is particularly sensitive to feedback that can guide behavioral adjustments, consistent with other work. In contrast, neither theta nor delta activity were sensitive to the difference between negative and neutral feedback, though both frequencies discriminated between positive, and non-positive (neutral or negative) feedback. Interestingly, in the time domain, we observed a linear relationship in the amplitude of the feedback-related negativity (neutral>negative>positive), a component of the event-related brain potential thought to index a specific kind of reinforcement learning signal called a reward prediction error. Taken together, these results suggest that the reinforcement learning system treats neutral feedback as a special case, providing valuable information about the electrophysiological measures used to index the cognitive function of frontal midline cortex. PMID:27378537

  13. Well separated trion and neutral excitons on superacid treated MoS2 monolayers

    Science.gov (United States)

    Cadiz, Fabian; Tricard, Simon; Gay, Maxime; Lagarde, Delphine; Wang, Gang; Robert, Cedric; Renucci, Pierre; Urbaszek, Bernhard; Marie, Xavier

    2016-06-01

    Developments in optoelectronics and spin-optronics based on transition metal dichalcogenide monolayers (MLs) need materials with efficient optical emission and well-defined transition energies. In as-exfoliated MoS2 MLs, the photoluminescence (PL) spectra even at low temperature consist typically of broad, overlapping contributions from neutral, charged excitons (trions) and localized states. Here, we show that in superacid treated MoS2 MLs, the PL intensity increases by up to 60 times at room temperature. The neutral and charged exciton transitions are spectrally well separated in PL and reflectivity at T = 4 K, with linewidth for the neutral exciton of 15 meV, but both transitions have similar intensities compared to the ones in as-exfoliated MLs at the same temperature. Time resolved experiments uncover picoseconds recombination dynamics analyzed separately for charged and neutral exciton emissions. Using the chiral interband selection rules, we demonstrate optically induced valley polarization for both complexes and valley coherence for only the neutral exciton.

  14. GENERATION OF ELECTRIC CURRENTS IN THE CHROMOSPHERE VIA NEUTRAL-ION DRAG

    International Nuclear Information System (INIS)

    We consider the generation of electric currents in the solar chromosphere where the ionization level is typically low. We show that ambient electrons become magnetized even for weak magnetic fields (30 G); that is, their gyrofrequency becomes larger than the collision frequency while ion motions continue to be dominated by ion-neutral collisions. Under such conditions, ions are dragged by neutrals, and the magnetic field acts as if it is frozen-in to the dynamics of the neutral gas. However, magnetized electrons drift under the action of the electric and magnetic fields induced in the reference frame of ions moving with the neutral gas. We find that this relative motion of electrons and ions results in the generation of quite intense electric currents. The dissipation of these currents leads to resistive electron heating and efficient gas ionization. Ionization by electron-neutral impact does not alter the dynamics of the heavy particles; thus, the gas turbulent motions continue even when the plasma becomes fully ionized, and resistive dissipation continues to heat electrons and ions. This heating process is so efficient that it can result in typical temperature increases with altitude as large as 0.1-0.3 eV km-1. We conclude that this process can play a major role in the heating of the chromosphere and corona.

  15. Investigation of the Neutral Gas Pressure Effect on the Metal Resistive Bolometer

    International Nuclear Information System (INIS)

    The bolometer system planned for W7-X consists mainly of metal (Au) resistive detector arrays. All the detectors are exposed to neutral gas environment. The thin bolometer foil used for detecting the radiated power loss may be sensitive to the neutral gas pressure due to the strain gauge effect. Recently, a prototype of this kind of bolometer camera consisting of 12 channels has been installed on the cylindrical plasma device VINETA in order to investigate the influences of the neutral gas pressure on the bolometer signals. Experiments are carried out for Ar-discharges under different gas pressure conditions. It is found that the pressure effect of the neutral gas can make considerable contributions, thus inducing non-negligible errors of the results in most of the investigated cases. Using the VINETA plasmas (Ar, Tee-19 m-3) as examples, the paper demonstrates and discusses how to minimize the neutral gas effects, especially in the data analysis process. The radiated power and the radiation intensity profile obtained in helicon discharges are presented

  16. Particle reflection and TFTR neutral beam diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kugel, H.W.; O`Connor, T.E.; Newman, R.A.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1992-04-01

    Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12{degrees}). Beamline calorimeters, of a ``V``-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the ``V``, complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected.

  17. Particle reflection and TFTR neutral beam diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Kamperschroer, J.H.; Grisham, L.R.; Kugel, H.W.; O' Connor, T.E.; Newman, R.A.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1992-04-01

    Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12{degrees}). Beamline calorimeters, of a V''-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the V'', complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected.

  18. Quasi-neutral theory of epidemic outbreaks.

    Science.gov (United States)

    Pinto, Oscar A; Muñoz, Miguel A

    2011-01-01

    Some epidemics have been empirically observed to exhibit outbreaks of all possible sizes, i.e., to be scale-free or scale-invariant. Different explanations for this finding have been put forward; among them there is a model for "accidental pathogens" which leads to power-law distributed outbreaks without apparent need of parameter fine tuning. This model has been claimed to be related to self-organized criticality, and its critical properties have been conjectured to be related to directed percolation. Instead, we show that this is a (quasi) neutral model, analogous to those used in Population Genetics and Ecology, with the same critical behavior as the voter-model, i.e. the theory of accidental pathogens is a (quasi)-neutral theory. This analogy allows us to explain all the system phenomenology, including generic scale invariance and the associated scaling exponents, in a parsimonious and simple way. PMID:21760930

  19. Quasi-Neutral theory of epidemic outbreaks

    CERN Document Server

    Pinto, Oscar A

    2011-01-01

    Some epidemics have been empirically observed to exhibit outbreaks of all possible sizes, i.e., to be scalefree or scale-invariant. Different explanations for this finding have been put forward; among them there is a model for "accidental pathogens" which leads to power-law distributed outbreaks without apparent need of parameter fine tuning. This model has been claimed to be related to self-organized criticality, and its critical properties have been conjectured to be related to directed percolation. Instead, we show that this is a (quasi) neutral model, analogous to those used in Population Genetics and Ecology, with the same critical behavior as the voter-model, i.e. the theory of accidental pathogens is a (quasi)-neutral theory. This analogy allows us to explain all the system phenomenology, including generic scale invariance and the associated scaling exponents, in a parsimonious and simple way.

  20. Geometry of Killing spinors in neutral signature

    CERN Document Server

    Klemm, Dietmar

    2015-01-01

    We classify the supersymmetric solutions of minimal $N=2$ gauged supergravity in four dimensions with neutral signature. They are distinguished according to the sign of the cosmological constant and whether the vector field constructed as a bilinear of the Killing spinor is null or non-null. In neutral signature the bilinear vector field can be spacelike, which is a new feature not arising in Lorentzian signature. In the $\\Lambda0$ non-null case, the manifold is a fibration over a Lorentzian Gauduchon-Tod base space. Finally, in the $\\Lambda>0$ null class, the metric is contained in the Kundt family, and it turns out that the holonomy is reduced to ${\\rm Sim}(1)\\times{\\rm Sim}(1)$. There appear no self-dual solutions in the null class for either sign of the cosmological constant.

  1. Limits on charm-changing neutral currents

    International Nuclear Information System (INIS)

    From data on D0, anti D0 decays, we get an upper limit on the mass difference delta m of the two CP eigenstates. Due to a critical dependence of delta m on QCD corrections, this bound cannot exclude large (gL,gR) charm-changing neutral couplings. Limits on neutrino production of charm by neutral currents and of charm decay into e+e- + hadrons are then necessary to further constrain the couplings. However, if the (c,u) current is assumed to be pure left handed, delta m gives the severe bound /gsub(L)/ -3. This is a confirmation of the Glashow-Iliopoulos-Maiani mechanism in the charm sector. (orig.)

  2. Non-neutral theory of biodiversity

    Science.gov (United States)

    Bianconi, G.; Ferretti, L.; Franz, S.

    2009-07-01

    We present a non-neutral stochastic model for the dynamics taking place in a meta-community ecosystems in the presence of migration. The model provides a framework for describing the emergence of multiple ecological scenarios and behaves in two extreme limits either as the unified neutral theory of biodiversity or as the Bak-Sneppen model. Interestingly, the model shows a condensation phase transition where one species becomes the dominant one, the diversity in the ecosystems is strongly reduced and the ecosystem is non-stationary. This phase transition extends the principle of competitive exclusion to open ecosystems and might be relevant for the study of the impact of invasive species in native ecologies.

  3. Net Neutrality and Quality of Service

    CERN Document Server

    Altman, Eitan; Wong, Sulan; Xu, Manjesh Kumar Hanawal 'and' Yuedong

    2011-01-01

    2010 has witnessed many public consultations around the world concerning Net neutrality. A second legislative phase that may follow, could involve various structural changes in the Internet. The status that the Internet access has in Europe as a universal service evolves as the level of quality of service (QoS) to be offered improves. If guarantees on QoS are to be imposed, as requested by several economic actors, it would require introducing new indicators of quality of services, as well as regulation legislation and monitoring of the offered levels of QoS. This tendency in Europe may change the nature of the Internet from a best effort network to, perhaps, a more expensive one, that offers guaranteed performance. This paper presents an overview of the above issues as well as an overview of recent research on net-neutrality, with an emphasis on game theoretical approaches.

  4. On exponential stabilizability of linear neutral systems

    Directory of Open Access Journals (Sweden)

    Dusser Xavier

    2001-01-01

    Full Text Available In this paper, we deal with linear neutral functional differential systems. Using an extended state space and an extended control operator, we transform the initial neutral system in an infinite dimensional linear system. We give a sufficient condition for admissibility of the control operator B , conditions under which operator B can be acceptable in order to work with controllability and stabilizability. Necessary and sufficient conditions for exact controllability are provided; in terms of a gramian of controllability N ( μ . Assuming admissibility and exact controllability, a feedback control law is defined from the inverse of the operator N ( μ in order to stabilize exponentially the closed loop system. In this case, the semigroup generated by the closed loop system has an arbitrary decay rate.

  5. Monochromaticity in neutral evolutionary network models.

    Science.gov (United States)

    Halu, Arda; Bianconi, Ginestra

    2012-12-01

    Recent studies on epistatic networks of model organisms have unveiled a certain type of modular property called monochromaticity in which the networks are clustered into functional modules that interact with each other through the same type of epistasis. Here, we propose and study three epistatic network models that are inspired by the duplication-divergence mechanism to gain insight into the evolutionary basis of monochromaticity and to test if it can be explained as the outcome of a neutral evolutionary hypothesis. We show that the epistatic networks formed by these stochastic evolutionary models have monochromaticity conflict distributions that are centered close to zero and are statistically significantly different from their randomized counterparts. In particular, the last model we propose yields a strictly monochromatic solution. Our results agree with the monochromaticity findings in real organisms and point toward the possible role of a neutral mechanism in the evolution of this phenomenon. PMID:23367998

  6. Measurement of neutral current coherent neutral pion production on carbon in a few-GeV neutrino beam

    OpenAIRE

    Kurimoto, Y; Alcaraz-Aunion, J. L.; Brice, S J; Bugel, L.; Catala-Perez, J.; Cheng, G.; Conrad, J.M.; Djurcic, Z.; Dore, U.; Finley, D. A.; Franke, A. J.; C. Giganti; Gomez-Cadenas, J. J.; Guzowski, P.; Hanson, A.

    2010-01-01

    The SciBooNE Collaboration reports a measurement of neutral current coherent neutral pion production on carbon by a muon neutrino beam with average energy 0.8 GeV. The separation of coherent from inclusive neutral pion production has been improved by detecting recoil protons from resonant neutral pion production. We measure the ratio of the neutral current coherent neutral pion production to total charged current cross sections to be (1.16 +/- 0.24) x 10-2. The ratio of charged current cohere...

  7. The discourse of neutrality in the press

    OpenAIRE

    Melo, Sandra Helena Dias de

    2010-01-01

    The goal here is to show how writing and style handbooks for journalists make a neutral image of news text and the press. Considering that language is not transparent nor simply a tool for communication (FAIRCLOUGH, 2001), I analyzed here how information, the prime object of the press, tends to be seen as an impartial product, based on techniques for standardizing journalistic language. For that purpose, an analysis was made of the handbooks produced by the newspapers Folha de S. Paulo and O ...

  8. Neutral kaon photoproduction on the deuteron

    CERN Document Server

    Salam, A; Miyagawa, K

    2009-01-01

    Neutral kaon photoproduction on the deuteron has been investigated by including the final state effects and compared with the experimental data. Comparison shows that the models used in this calculation can reproduce the data in the $\\Sigma$ channel regions fairly well but still give over predictions in the $\\Lambda$ channel. It seems that the tensor target asymmetries are more suitable for studying the final state effects. The extractions of the elementary photoproduction amplitude are also demonstrated.

  9. LINEARIZED OSCILLATIONS FOR NEUTRAL DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    李建利; 申建华

    2004-01-01

    Consider the nonlinear neutral delay differential equation d/dt[x(t)-P(t)g(x(t-τ))]+Q(t)h(x(t-σ))=01t≥t0,where P1Q∈C([t01∞),R(τ>01,σ≥0,We obtain a linearized oscillation result by an associate linear equation in the case when liminf P(t)=p0∈[-1,0)。

  10. Stability of Stochastic Neutral Cellular Neural Networks

    Science.gov (United States)

    Chen, Ling; Zhao, Hongyong

    In this paper, we study a class of stochastic neutral cellular neural networks. By constructing a suitable Lyapunov functional and employing the nonnegative semi-martingale convergence theorem we give some sufficient conditions ensuring the almost sure exponential stability of the networks. The results obtained are helpful to design stability of networks when stochastic noise is taken into consideration. Finally, two examples are provided to show the correctness of our analysis.

  11. Commentary: Ownership Neutrality and Practical Complications

    OpenAIRE

    Shay, Stephen E.

    2009-01-01

    In "Reconsidering the Taxation of Foreign Income," Jim Hines analyzes the consequences of taxing, as opposed to exempting, active foreign business income by comparing the expected effects on capital ownership of a "pure" worldwide income taxation system with the effects on capital ownership of a "pure" territorial taxation regime. Consistent with his earlier work, Hines asserts that a capital ownership neutrality analysis supports exempting foreign active business income from home country res...

  12. Oscillations of neutral B mesons systems

    OpenAIRE

    Boucrot, J.

    1999-01-01

    The oscillation phenomenon in the neutral B mesons systems is now well established. The motivations and principles of the measurements are given; then the most recent results from the LEP experiments, the CDF collaboration at Fermilab and the SLD collaboration at SLAC are reviewed. The present world average of the $\\bd$ meson oscillation frequency is $\\dmd = 0.471 \\pm 0.016 \\ps$ and the lower limit on the $\\bs$ oscillation frequency is $\\dms > 12.4 \\ps at 95% CL$.

  13. Network Non-Neutrality through Preferential Signaling

    OpenAIRE

    Hanawal, Manjesh Kumar; Altman, Eitan

    2013-01-01

    One of the central issues in the debate on network neutrality has been whether one should allow or prevent preferential treatment by an internet service provider (ISP) of traffic according to its origin. This raised the question of whether to allow an ISP to have exclusive agreement with a content provider (CP). In this paper we consider discrimination in the opposite direction. We study the impact that a CP can have on the benefits of several competing ISPs by sharing private information con...

  14. Molecular clock in neutral protein evolution

    Directory of Open Access Journals (Sweden)

    Wilke Claus O

    2004-08-01

    Full Text Available Abstract Background A frequent observation in molecular evolution is that amino-acid substitution rates show an index of dispersion (that is, ratio of variance to mean substantially larger than one. This observation has been termed the overdispersed molecular clock. On the basis of in silico protein-evolution experiments, Bastolla and coworkers recently proposed an explanation for this observation: Proteins drift in neutral space, and can temporarily get trapped in regions of substantially reduced neutrality. In these regions, substitution rates are suppressed, which results in an overall substitution process that is not Poissonian. However, the simulation method of Bastolla et al. is representative only for cases in which the product of mutation rate μ and population size Ne is small. How the substitution process behaves when μNe is large is not known. Results Here, I study the behavior of the molecular clock in in silico protein evolution as a function of mutation rate and population size. I find that the index of dispersion decays with increasing μNe, and approaches 1 for large μNe . This observation can be explained with the selective pressure for mutational robustness, which is effective when μNe is large. This pressure keeps the population out of low-neutrality traps, and thus steadies the ticking of the molecular clock. Conclusions The molecular clock in neutral protein evolution can fall into two distinct regimes, a strongly overdispersed one for small μNe, and a mostly Poissonian one for large μNe. The former is relevant for the majority of organisms in the plant and animal kingdom, and the latter may be relevant for RNA viruses.

  15. Power threshold for neutral beam current drive

    International Nuclear Information System (INIS)

    For fully noninductive current drive in tokamaks using neutral beams, there is a power and density threshold condition, setting a minimum value for P3/2/n2. If this condition is not met, stationary state cannot occur, and a tokamak discharge will collapse. This is a consequence of the coupling between current and electron temperature, or between current drive efficiency and energy confinement time. 4 figs

  16. Risk-neutral systemic risk indicators

    OpenAIRE

    Allan M. Malz

    2013-01-01

    This paper describes a set of indicators of systemic risk computed from current market prices of equity and equity index options. It displays results from a prototype version, computed daily from January 2006 to January 2013. The indicators represent a systemic risk event as the realization of an extreme loss on a portfolio of large-intermediary equities. The technique for computing them combines risk-neutral return distributions with implied return correlations drawn from option prices, tyin...

  17. W+- pairs and neutral currents at ISABELLE

    International Nuclear Information System (INIS)

    A report is presented on two different types of processes which may form part of the weak interactions program. The first is the production of pairs of charged weak bosons in the process pp → W+W-X; the second involves searching for neutral current effects in the rate for ordinary lepton production, without measuring any charge asymmetry or helicities using the reaction pp → l+l-X

  18. Ultracold neutral plasma expansion in two dimensions

    CERN Document Server

    Cummings, E A; Durfee, D S; Bergeson, S D

    2005-01-01

    We extend an isothermal thermal model of ultracold neutral plasma expansion to systems without spherical symmetry, and use this model to interpret new fluorescence measurements on these plasmas. By assuming a self-similar expansion, it is possible to solve the fluid equations analytically and to include velocity effects to predict the fluorescence signals. In spite of the simplicity of this approach, the model reproduces the major features of the experimental data.

  19. Post-exposure vaccination improves gammaherpesvirus neutralization.

    OpenAIRE

    Laurent Gillet; May, Janet S.; Stevenson, Philip G.

    2007-01-01

    Herpesvirus carriers transmit infection despite making virus-specific antibodies. Thus, their antibody responses are not necessarily optimal. An important question for infection control is whether vaccinating carriers might improve virus neutralization. The antibody response to murine gamma-herpesvirus-68 (MHV-68) blocks cell binding, but fails to block and even enhances an IgG Fc receptor-dependent infection of myeloid cells. Viral membrane fusion therefore remains intact. Although gH/gL-spe...

  20. Toxic emissions and devalued CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    friendly effects of substituting wood burning for fossil fuels. With reference to Bent Sørensen's classical work on 'Renewable Energy' the assumption of CO2-neutrality regarding incineration is problematised when applied to plants with long rotation periods as trees. Registered CO2-emissions from wood...... burning are characterised together with particle and PAH emissions. The positive treatment of wood stove-technology in the Danish strategy for sustainable development (draft 2007) is critically evaluated and approaches to better regulation are identified....

  1. TFTR neutral beam injected power measurement

    International Nuclear Information System (INIS)

    Energy flow within TFTR neutral beamlines is measured with a waterflow calorimetry system capable of simultaneously measuring the energy deposited within four heating beamlines (three ion sources each), or of measuring the energy deposited in a separate neutral beam test stand. Of the energy extracted from the ion source on the well-instrumented test stand, 99.5±3.5% can be accounted for. When the ion deflection magnet is energized, however, 6.5% of the extracted energy is lost. This loss is attributed to a spray of devious particles onto unmonitored surfaces. A 30% discrepancy is also observed between energy measurements on the internal beamline calorimeter and energy measurements on a calorimeter located in the test stand target chamber. Particle reflection from the flat plate calorimeter in the target chamber, which the incident beam strikes at a near-grazing angle of 12 degree, is the primary loss of this energy. A slight improvement in energy accountability is observed as the beam pulse length is increased. This improvement is attributed to systematic error in the sensitivity of the energy measurement to small fluctuations in the supply water temperature. An overall accuracy of 15% is estimated for the total power injected into TFTR. Contributions to this error are uncertainties in the beam neutralization efficiency, reionization and beam scrape-off in the drift duct, and fluctuations in the temperature of the supply water

  2. Laboratory simulation of cometary neutral gas ionization

    International Nuclear Information System (INIS)

    The laboratory simulation of the interaction of the solar wind with a comet is used to study the cometary neutral gas ionization. The experiment is carried out in the UCR T-1 facility with an ice ball as the comet model. Photographs and data are taken with a variety of values of the solar wind velocity, interplanetary magnetic field (IMF), and comet configurations. The results show that the cometary neutral gas ionization depends on both the velocity of the solar wind and the interplanetary magnetic field. The plasma cloud surrounding the comet is visible only when the solar wind velocity and IMF are both above certain minimum values. This velocity dependent phenomena is explained by Alfven's critical ionization velocity effect. The critical magnetic field may be explained by assuming two stream lower hybrid instability as a triggering mechanism for the ionization of the neutral gas by plasma flow. Critical upper and lower limits for the magnetic field, required by anomalous ionization, are also derived that satisfy the experimental observations

  3. Neutral Color Semitransparent Microstructured Perovskite Solar Cells

    KAUST Repository

    Eperon, Giles E.

    2014-01-28

    Neutral-colored semitransparent solar cells are commercially desired to integrate solar cells into the windows and cladding of buildings and automotive applications. Here, we report the use of morphological control of perovskite thin films to form semitransparent planar heterojunction solar cells with neutral color and comparatively high efficiencies. We take advantage of spontaneous dewetting to create microstructured arrays of perovskite "islands", on a length-scale small enough to appear continuous to the eye yet large enough to enable unattenuated transmission of light between the islands. The islands are thick enough to absorb most visible light, and the combination of completely absorbing and completely transparent regions results in neutral transmission of light. Using these films, we fabricate thin-film solar cells with respectable power conversion efficiencies. Remarkably, we find that such discontinuous films still have good rectification behavior and relatively high open-circuit voltages due to the inherent rectification between the n- and p-type charge collection layers. Furthermore, we demonstrate the ease of "color-tinting" such microstructured perovksite solar cells with no reduction in performance, by incorporation of a dye within the hole transport medium. © 2013 American Chemical Society.

  4. Electromagnetic instability in a magnetic neutral sheet

    International Nuclear Information System (INIS)

    The structure of electromagnetic perturbations in a magnetic neutral sheet was analyzed within the framework of a Vlasov-Maxwellian picture. In the geomagnetic tail, there exists a stable magnetic neutral sheet of about 10 R-E (earth radius) thick. However, it has been reported that the thickness of this sheet is reduced to about 1 R-E just before the onset of substorms, and this shows the critical thickness of sheet destruction. In the laboratory experiment, a stable neutral sheet is produced by induction, and its thickness also becomes as thin as about the ion Larmor radius, which is defined far outside the sheet region, before the sudden destruction of the sheet current. Tearing instability cannot explain this abrupt destruction. Then it can be considered that the tearing instability is stabilized by some mechanisms. Consequently, it becomes important to look for another perturbation unstable in a thin sheet while stable in a thick sheet. Here, a magnetically compressional mode propagating in the direction of the unperturbed current which produced reverse field is considered. Equilibrium configuration and particle orbits, perturbations, resulted eigenfunctions and dispersion relations are described to show that the above mode becomes unstable in a thin sheet, and the critical thickness is about the ion Larmor radius just outside the sheet region. When the typical field intensity in the geomagnetic tail is taken, the time scale of this instability becomes about 800 sec. This value coincides with the observed flare time scale. (Wakatsuki, Y.)

  5. Measurements of neutral and ion velocity distribution functions in a Hall thruster

    Science.gov (United States)

    Svarnas, Panagiotis; Romadanov, Iavn; Diallo, Ahmed; Raitses, Yevgeny

    2015-11-01

    Hall thruster is a plasma device for space propulsion. It utilizes a cross-field discharge to generate a partially ionized weakly collisional plasma with magnetized electrons and non-magnetized ions. The ions are accelerated by the electric field to produce the thrust. There is a relatively large number of studies devoted to characterization of accelerated ions, including measurements of ion velocity distribution function using laser-induced fluorescence diagnostic. Interactions of these accelerated ions with neutral atoms in the thruster and the thruster plume is a subject of on-going studies, which require combined monitoring of ion and neutral velocity distributions. Herein, laser-induced fluorescence technique has been employed to study neutral and single-charged ion velocity distribution functions in a 200 W cylindrical Hall thruster operating with xenon propellant. An optical system is installed in the vacuum chamber enabling spatially resolved axial velocity measurements. The fluorescence signals are well separated from the plasma background emission by modulating the laser beam and using lock-in detectors. Measured velocity distribution functions of neutral atoms and ions at different operating parameters of the thruster are reported and analyzed. This work was supported by DOE contract DE-AC02-09CH11466.

  6. An Insider Threat Neutralization Mitigation Model Predicated On Cognitive Dissonance (ITNMCD

    Directory of Open Access Journals (Sweden)

    Keshnee Padayachee

    2015-07-01

    Full Text Available The insider threat concern is a complex issue, as the problem domain intersects the social, technical and socio-technical dimensions. Consequently, counteracting the insider threat involves influencing the insider’s perceptions and behaviour in order to ensure compliance. When an individual’s actions and beliefs are incongruent, this induces a phenomenon known as cognitive dissonance. In order to reduce this dissonance, individuals are self-motivated either to change their behaviours or beliefs, or to rationalize their behaviour. Neutralization is a technique used by criminals to rationalize maleficence. In terms of the insider threat, it has been proposed that if the justifications for committing an offence are eliminated, then the insider is less likely to commit the offence. This process is known as neutralization mitigation. The research reported on here proposes that inducing cognitive dissonance may be a means of mitigating the neutralizations that the insider may use to justify maleficence. To integrate these concepts into a pragmatic implementable solution the Insider Threat Neutralization Mitigation model predicated on Cognitive Dissonance (ITNMCD is proposed. A proof-of-concept was developed and the model concept was evaluated using the design science method.

  7. Initiation of immune tolerance-controlled HIV gp41 neutralizing B cell lineages.

    Science.gov (United States)

    Zhang, Ruijun; Verkoczy, Laurent; Wiehe, Kevin; Munir Alam, S; Nicely, Nathan I; Santra, Sampa; Bradley, Todd; Pemble, Charles W; Zhang, Jinsong; Gao, Feng; Montefiori, David C; Bouton-Verville, Hilary; Kelsoe, Garnett; Larimore, Kevin; Greenberg, Phillip D; Parks, Robert; Foulger, Andrew; Peel, Jessica N; Luo, Kan; Lu, Xiaozhi; Trama, Ashley M; Vandergrift, Nathan; Tomaras, Georgia D; Kepler, Thomas B; Moody, M Anthony; Liao, Hua-Xin; Haynes, Barton F

    2016-04-27

    Development of an HIV vaccine is a global priority. A major roadblock to a vaccine is an inability to induce protective broadly neutralizing antibodies (bnAbs). HIV gp41 bnAbs have characteristics that predispose them to be controlled by tolerance. We used gp41 2F5 bnAb germline knock-in mice and macaques vaccinated with immunogens reactive with germline precursors to activate neutralizing antibodies. In germline knock-in mice, bnAb precursors were deleted, with remaining anergic B cells capable of being activated by germline-binding immunogens to make gp41-reactive immunoglobulin M (IgM). Immunized macaques made B cell clonal lineages targeted to the 2F5 bnAb epitope, but 2F5-like antibodies were either deleted or did not attain sufficient affinity for gp41-lipid complexes to achieve the neutralization potency of 2F5. Structural analysis of members of a vaccine-induced antibody lineage revealed that heavy chain complementarity-determining region 3 (HCDR3) hydrophobicity was important for neutralization. Thus, gp41 bnAbs are controlled by immune tolerance, requiring vaccination strategies to transiently circumvent tolerance controls. PMID:27122615

  8. Initiation of immune tolerance–controlled HIV gp41 neutralizing B cell lineages

    Science.gov (United States)

    Zhang, Ruijun; Verkoczy, Laurent; Wiehe, Kevin; Alam, S. Munir; Nicely, Nathan I.; Santra, Sampa; Bradley, Todd; Pemble, Charles W.; Zhang, Jinsong; Gao, Feng; Montefiori, David C.; Bouton-Verville, Hilary; Kelsoe, Garnett; Larimore, Kevin; Greenberg, Phillip D.; Parks, Robert; Foulger, Andrew; Peel, Jessica N.; Luo, Kan; Lu, Xiaozhi; Trama, Ashley M.; Vandergrift, Nathan; Tomaras, Georgia D.; Kepler, Thomas B.; Moody, M. Anthony; Liao, Hua-Xin; Haynes, Barton F.

    2016-01-01

    Development of an HIV vaccine is a global priority. A major roadblock to a vaccine is an inability to induce protective broadly neutralizing antibodies (bnAbs). HIV gp41 bnAbs have characteristics that predispose them to be controlled by tolerance. We used gp41 2F5 bnAb germline knock-in mice and macaques vaccinated with immunogens reactive with germline precursors to activate neutralizing antibodies. In germline knock-in mice, bnAb precursors were deleted, with remaining anergic B cells capable of being activated by germline-binding immunogens to make gp41-reactive immunoglobulin M (IgM). Immunized macaques made B cell clonal lineages targeted to the 2F5 bnAb epitope, but 2F5-like antibodies were either deleted or did not attain sufficient affinity for gp41-lipid complexes to achieve the neutralization potency of 2F5. Structural analysis of members of a vaccine-induced antibody lineage revealed that heavy chain complementarity-determining region 3 (HCDR3) hydrophobicity was important for neutralization. Thus, gp41 bnAbs are controlled by immune tolerance, requiring vaccination strategies to transiently circumvent tolerance controls. PMID:27122615

  9. Neutral theory and the species abundance distribution: recent developments and prospects for unifying niche and neutral perspectives.

    Science.gov (United States)

    Matthews, Thomas J; Whittaker, Robert J

    2014-06-01

    Published in 2001, The Unified Neutral Theory of Biodiversity and Biogeography (UNTB) emphasizes the importance of stochastic processes in ecological community structure, and has challenged the traditional niche-based view of ecology. While neutral models have since been applied to a broad range of ecological and macroecological phenomena, the majority of research relating to neutral theory has focused exclusively on the species abundance distribution (SAD). Here, we synthesize the large body of work on neutral theory in the context of the species abundance distribution, with a particular focus on integrating ideas from neutral theory with traditional niche theory. First, we summarize the basic tenets of neutral theory; both in general and in the context of SADs. Second, we explore the issues associated with neutral theory and the SAD, such as complications with fitting and model comparison, the underlying assumptions of neutral models, and the difficultly of linking pattern to process. Third, we highlight the advances in understanding of SADs that have resulted from neutral theory and models. Finally, we focus consideration on recent developments aimed at unifying neutral- and niche-based approaches to ecology, with a particular emphasis on what this means for SAD theory, embracing, for instance, ideas of emergent neutrality and stochastic niche theory. We put forward the argument that the prospect of the unification of niche and neutral perspectives represents one of the most promising future avenues of neutral theory research. PMID:25360266

  10. Emotionally Neutral Stimuli Are Not Neutral in Schizophrenia: A Mini Review of Functional Neuroimaging Studies

    Science.gov (United States)

    Potvin, Stéphane; Tikàsz, Andràs; Mendrek, Adrianna

    2016-01-01

    Reliable evidence shows that schizophrenia patients tend to experience negative emotions when presented with emotionally neutral stimuli. Similarly, several functional neuroimaging studies show that schizophrenia patients have increased activations in response to neutral material. However, results are heterogeneous. Here, we review the functional neuroimaging studies that have addressed this research question. Based on the 36 functional neuroimaging studies that we retrieved, it seems that the increased brain reactivity to neutral stimuli is fairly common in schizophrenia, but that the regions involved vary considerably, apart from the amygdala. Prefrontal and cingulate sub-regions and the hippocampus may also be involved. By contrasts, results in individuals at risk for psychosis are less consistent. In schizophrenia patients, results are less consistent in the case of studies using non-facial stimuli, explicit processing paradigms, and/or event-related designs. This means that human faces may convey subtle information (e.g., trustworthiness) other than basic emotional expressions. It also means that the aberrant brain reactivity to neutral stimuli is less likely to occur when experimental paradigms are too cognitively demanding as well as in studies lacking statistical power. The main hypothesis proposed to account for this increased brain reactivity to neutral stimuli is the aberrant salience hypothesis of psychosis. Other investigators propose that the aberrant brain reactivity to neutral stimuli in schizophrenia results from abnormal associative learning, untrustworthiness judgments, priming effects, and/or reduced habituation to neutral stimuli. In the future, the effects of antipsychotics on this aberrant brain reactivity will need to be determined, as well as the potential implication of sex/gender. PMID:27445871

  11. Emotionally Neutral Stimuli Are Not Neutral in Schizophrenia: A Mini Review of Functional Neuroimaging Studies.

    Science.gov (United States)

    Potvin, Stéphane; Tikàsz, Andràs; Mendrek, Adrianna

    2016-01-01

    Reliable evidence shows that schizophrenia patients tend to experience negative emotions when presented with emotionally neutral stimuli. Similarly, several functional neuroimaging studies show that schizophrenia patients have increased activations in response to neutral material. However, results are heterogeneous. Here, we review the functional neuroimaging studies that have addressed this research question. Based on the 36 functional neuroimaging studies that we retrieved, it seems that the increased brain reactivity to neutral stimuli is fairly common in schizophrenia, but that the regions involved vary considerably, apart from the amygdala. Prefrontal and cingulate sub-regions and the hippocampus may also be involved. By contrasts, results in individuals at risk for psychosis are less consistent. In schizophrenia patients, results are less consistent in the case of studies using non-facial stimuli, explicit processing paradigms, and/or event-related designs. This means that human faces may convey subtle information (e.g., trustworthiness) other than basic emotional expressions. It also means that the aberrant brain reactivity to neutral stimuli is less likely to occur when experimental paradigms are too cognitively demanding as well as in studies lacking statistical power. The main hypothesis proposed to account for this increased brain reactivity to neutral stimuli is the aberrant salience hypothesis of psychosis. Other investigators propose that the aberrant brain reactivity to neutral stimuli in schizophrenia results from abnormal associative learning, untrustworthiness judgments, priming effects, and/or reduced habituation to neutral stimuli. In the future, the effects of antipsychotics on this aberrant brain reactivity will need to be determined, as well as the potential implication of sex/gender. PMID:27445871

  12. Neutral dissociation of superexcited states in carbon monoxide

    International Nuclear Information System (INIS)

    Neutral photodissociation of CO has been investigated using synchrotron light in the range 19-26 eV by observing dispersed fluorescence from excited neutral C atoms. Follow-up ab initio calculations support the observed neutral carbon excitation functions, which to a large extent are associated with the CO Rydberg series converging to the CO+ C and D states. (author)

  13. Overview of neutral beam injector technology developments at universities

    International Nuclear Information System (INIS)

    Activities of universities on the neutral beam injector developments have been overviewed. The subjects consist of NBI construction, components developments and system analyses, which are intensively studied at universities. Although neutral beam injector technologies are present day top topics, however, still a lot of efforts with flexible ideas are necessary to realize reactor relevant neutral beam injector system. (author)

  14. Single neutral pion production by charged-current $\\bar{\

    CERN Document Server

    Aliaga, L; Bercellie, A; Bodek, A; Bravar, A; Brooks, W K; Butkevich, A; Caicedo, D A Martinez; Carneiro, M F; Christy, M E; Chvojka, J; da Motta, H; Devan, J; Dytman, S A; Díaz, G A; Eberly, B; Felix, J; Fields, L; Fine, R; Gago, A M; Gallagher, H; Gran, R; Harris, D A; Higuera, A; Hurtado, K; Kordosky, M; Le, T; Maher, E; Manly, S; Mann, W A; Marshall, C M; McFarland, K S; McGivern, C L; McGowan, A M; Miller, J; Morfín, J G; Mousseau, J; Nelson, J K; Norrick, A; Osta, J; Palomino, J L; Paolone, V; Park, J; Patrick, C E; Perdue, G N; Rakotondravohitra, L; Ramirez, M A; Ransome, R D; Ray, H; Ren, L; Rodrigues, P A; Ruterbories, D; Schellman, H; Schmitz, D W; Sobczyk, J T; Salinas, C J Solano; Tagg, N; Tice, B G; Valencia, E; Walton, T; Wolcott, J; Yepes-Ramirez, H; Zavala, G; Zhang, D; Ziemer, B P

    2015-01-01

    Single neutral pion production via muon antineutrino charged-current interactions in plastic scintillator (CH) is studied using the \\minerva detector exposed to the NuMI low-energy, wideband antineutrino beam at Fermilab. Measurement of this process constrains models of neutral pion production in nuclei, which is important because the neutral-current analog is a background for $\\bar{\

  15. Fiscal Neutrality and Local Choice in Public Education.

    Science.gov (United States)

    Weber, William L.

    1991-01-01

    Extends Feldstein's notion of wealth neutrality to embrace fiscal neutrality, using a representative consumer context. Employs an "ideal" demand system to model school district expenditures in a general equilibrium framework. Rejects constant price and income elasticity demand models. Supports the fiscally neutral elasticity model varying by…

  16. Neutral hydrogen at high redshift: probing structure formation

    OpenAIRE

    Bagla, J. S.

    1998-01-01

    Large inhomogeneities in neutral hydrogen in the universe can be detected at redshifts $z \\leq 10$ using the redshifted 21cm line emission from atomic hydrogen. This paper reviews the expected evolution of neutral hydrogen and presents estimates for future surveys of HI at $z \\approx 3$. We also discuss the possibility of detecting neutral hydrogen at higher redshifts.

  17. Analysis of Cross-Reactive Neutralizing Antibodies in Human HFMD Serum with an EV71 Pseudovirus-Based Assay

    Science.gov (United States)

    Jin, Jun; Xu, Lin; Sun, Shiyang; Jiang, Liping; Li, Xiaojun; Shao, Jie; Ma, Hongxia; Huang, Xueyong; Guo, Shijie; Chen, Haiying; Cheng, Tong; Yang, Lisheng; Su, Weiheng; Kong, Wei; Liang, Zhenglun; Jiang, Chunlai

    2014-01-01

    Hand, foot and mouth disease, associated with enterovirus 71 (EV71) infections, has recently become an important public health issue throughout the world. Serum neutralizing antibodies are major indicators of EV71 infection and protective immunity. However, the potential for cross-reactivity of neutralizing antibodies for different EV71 genotypes and subgenotypes is unclear. Here we measured the cross-reactive neutralizing antibody titers against EV71 of different genotypes or subgenotypes in sera collected from EV71-infected children and vaccine-inoculated children in a phase III clinical trial (ClinicalTrials.gov Identifier: NCT01636245) using a new pseudovirus-based neutralization assay. Antibodies induced by EV71-C4a were cross-reactive for different EV71 genotypes, demonstrating that C4a is a good candidate strain for an EV71 vaccine. Our study also demonstrated that this new assay is practical for analyses of clinical samples from epidemiological and vaccine studies. PMID:24964084

  18. Analysis of cross-reactive neutralizing antibodies in human HFMD serum with an EV71 pseudovirus-based assay.

    Directory of Open Access Journals (Sweden)

    Huafei Zhang

    Full Text Available Hand, foot and mouth disease, associated with enterovirus 71 (EV71 infections, has recently become an important public health issue throughout the world. Serum neutralizing antibodies are major indicators of EV71 infection and protective immunity. However, the potential for cross-reactivity of neutralizing antibodies for different EV71 genotypes and subgenotypes is unclear. Here we measured the cross-reactive neutralizing antibody titers against EV71 of different genotypes or subgenotypes in sera collected from EV71-infected children and vaccine-inoculated children in a phase III clinical trial (ClinicalTrials.gov Identifier: NCT01636245 using a new pseudovirus-based neutralization assay. Antibodies induced by EV71-C4a were cross-reactive for different EV71 genotypes, demonstrating that C4a is a good candidate strain for an EV71 vaccine. Our study also demonstrated that this new assay is practical for analyses of clinical samples from epidemiological and vaccine studies.

  19. Diagonality of weak neutral current and mixing amplitudes of neutral mesons

    International Nuclear Information System (INIS)

    A possibility to mix K deg - like systems into their antisystems is investigated in terms of multiquark models. The principle of neutral current diagonality is greatly employed. The scheme with two sets of quarks: four quarks with the charge -1/3 (''down''-quarks) and four quarks with the charge 2/3 (''up''-quarks) is considered. Six systems (antisystems), neutral in charge but ''charged'' in other quantum numbers are found, being referred to as ''down'' and ''up'' systems neutral in charge. The Feynman diagrams contribute into the mixing amplitudes of the indicated systems and into the corresponding antisystems in the fourth order of perturbation theory. The diagonality principle of neutral current signifies that the matrix 0 is a unitary one. Due to the diagonality principle of neutral current the divergences in the mixing amplitude are cancelled. The same result holds for the integral J2 containing the divergence of the approximately lsub(nt) type. All the hadrons with the exotic quantum numbers ''temperament'', ''beauty'', ''charm'', ''strangeness'' are shown to decay into stable hadronic states constructed of coventional quarks p and n

  20. Assessment of neutralizing and non-neutralizing antibody responses against Porcine circovirus 2 in vaccinated and non-vaccinated farmed pigs.

    Science.gov (United States)

    Worsfold, Cristina Solis; Dardari, Rkia; Law, Sampson; Eschbaumer, Michael; Nourozieh, Narges; Marshall, Frank; Czub, Markus

    2015-09-01

    Vaccination is the most efficacious procedure to curtail Porcine circovirus 2 (PCV2)-associated diseases (PCVAD). Experimental studies indicate that PCV2 vaccine-induced virus-neutralizing antibodies play a major role in protection from PCVAD. However, the immune response to PCV2 vaccination of pigs on farms is less clear. Analysing groups of age-matched vaccinated and non-vaccinated farmed pigs, we found significantly increased levels of virus-neutralizing antibodies only in vaccinated pigs belonging to the age group with the highest risk for developing PCVAD. Serum levels of PCV2 genomes were not different between corresponding age groups. Levels of antibodies directed against a linear peptide from the PCV2 capsid protein correlated with those of virus-neutralizing antibodies and reached the highest levels in older, non-vaccinated animals, pointing towards an intense interaction between PCV2-infected cells and the immune system. In conclusion, current PCV2 vaccines are in need of improvement to induce stronger and more rapid immunity to prevent PCV2 infection. PMID:26033118

  1. Site Specificity in Femtosecond Laser Desorption of Neutral H Atoms from Graphite(0001)

    DEFF Research Database (Denmark)

    Frigge, R.; Hoger, T.; Siemer, B.; Witte, H.; Silies, M.; Zacharias, H; Olsen, Thomas; Schiøtz, Jakob

    2010-01-01

    Femtosecond laser excitation and density functional theory reveal site and vibrational state specificity in neutral atomic hydrogen desorption from graphite induced by multiple electronic transitions. Multimodal velocity distributions witness the participation of ortho and para pair states of che...... chemisorbed hydrogen in the desorption process. Very slow velocities of 700 and 400  ms-1 for H and D atoms are associated with the desorption out of the highest vibrational state of a barrierless potential.......Femtosecond laser excitation and density functional theory reveal site and vibrational state specificity in neutral atomic hydrogen desorption from graphite induced by multiple electronic transitions. Multimodal velocity distributions witness the participation of ortho and para pair states of...

  2. New Modulation Strategy to Balance the Neutral-Point Voltage for Three-Level Neutral-Clamped Inverter Systems

    DEFF Research Database (Denmark)

    Choi, Uimin; Lee, June-Seok; Lee, Kyo-Beum

    2014-01-01

    This paper proposes a new modulation strategy that balances the neutral-point voltage for three-level neutral-clamped inverter systems. The proposed modulation replaces the P-type or N-type small switching states with other switching states that do not affect the neutral-point voltage. The zero and...

  3. Communication: Classical threshold law for ion-neutral-neutral three-body recombination

    International Nuclear Information System (INIS)

    A very recently method for classical trajectory calculations for three-body collision [Pérez-Ríos et al., J. Chem. Phys. 140, 044307 (2014)] has been applied to describe ion-neutral-neutral ternary processes for low energy collisions: 0.1 mK–10 mK. As a result, a threshold law for the three-body recombination cross section is obtained and corroborated numerically. The derived threshold law predicts the formation of weakly bound dimers, with binding energies comparable to the collision energy of the collisional partners. In this low energy range, this analysis predicts that molecular ions should dominate over molecular neutrals as the most products formed

  4. Universal threshold law for ion-neutral-neutral three-body recombination

    CERN Document Server

    Pérez-Ríos, Jesús

    2015-01-01

    A very recently method for classical trajectory calculations for three-body collision [J. P\\'{e}rez-R\\'{i}os, S. Ragole, J. Wang and C. H. Greene, J. Chem. Phys. {\\bf 140}, 044307 (2014)] has been applied to describe ion-neutral-neutral ternary processes for low energy collisions: 0.1 mK - 10 mK. As a result, a threshold law for the three-body recombination cross section is obtained and corroborated both, experimentally and numerically. The derived threshold law predicts the formation of weakly bound dimers, with binding energies comparable to the collision energy of the collisional partners. In this low energy range, this analysis predicts that molecular ions should dominate over molecular neutrals as the most products formed.

  5. Is the electrostatic force between a point charge and a neutral metallic object always attractive?

    CERN Document Server

    Levin, Michael

    2010-01-01

    We give an example of a geometry in which the electrostatic force between a point charge and a neutral metallic object is repulsive. The example consists of a point charge centered above a thin metallic hemisphere, positioned concave up. We show that this geometry has a repulsive regime using both a simple analytical argument and an exact calculation for an analogous two-dimensional geometry. Analogues of this geometry-induced repulsion can appear in many other contexts, including Casimir systems.

  6. Tunable Supercurrent at the Charge Neutrality Point via Strained Graphene Junctions

    OpenAIRE

    Alidoust, Mohammad; Linder, Jacob

    2011-01-01

    We theoretically calculate the charge-supercurrent through a ballistic graphene junction where superconductivity is induced via the proximity-effect. Both monolayer and bilayer graphene are considered, including the possibility of strain in the systems. We demonstrate that the supercurrent at the charge neutrality point can be tuned efficiently by means of mechanical strain. Remarkably, the supercurrent is enhanced or suppressed relative to the non-strained case depending on the direction of ...

  7. NONLINEAR STABILITY OF NATURAL RUNGE-KUTTA METHODS FOR NEUTRAL DELAY DIFFERENTIAL EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    Cheng-jian Zhang

    2002-01-01

    This paper first presents the stability analysis of theoretical solutions for a class of nonlinear neutral delay-differential equations (NDDEs). Then the numerical analogous results, of the natural Runge-Kutta (NRK) methods for the same class of nonlinear NDDEs,are given. In particular, it is shown that the (k, l)-algebraic stability of a RK method for ODEs implies the generalized asymptotic stability and the global stability of the induced NRK method.

  8. Ion-mediated interactions between net-neutral slabs: Weak and strong disorder effects

    OpenAIRE

    Ghodrat, Malihe; Naji, Ali; Komaie-Moghaddam, Haniyeh; Podgornik, Rudolf

    2015-01-01

    We investigate the effective interaction between two randomly charged but otherwise net-neutral, planar dielectric slabs immersed in an asymmetric Coulomb fluid containing a mixture of mobile monovalent and multivalent ions. The presence of charge disorder on the apposed bounding surfaces of the slabs leads to substantial qualitative changes in the way they interact, as compared with the standard picture provided by the van der Waals and image-induced, ion-depletion interactions. While, the l...

  9. B_s-anti-B_s Mixing in Z' Models with Flavor-Changing Neutral Currents

    OpenAIRE

    Barger, Vernon; Chiang, Cheng-Wei; Jiang, Jing; Langacker, Paul

    2004-01-01

    In models with an extra U(1)' gauge boson family non-universal couplings to the weak eigenstates of the standard model fermions generally induce flavor-changing neutral currents. This phenomenon leads to interesting results in various B meson decays, for which recent data indicate hints of new physics involving significant contributions from b -> s transitions. We analyze the B_s system, emphasizing the effects of a Z' on the mass difference and CP asymmetries.

  10. Characterization of Acid-neutralizing Basic Monomers in Co-solvent Systems by NMR

    OpenAIRE

    Laurence, Jennifer S.; Nelson, Benjamin N.; Ye, Qiang; Park, Jonggu; Spencer, Paulette

    2014-01-01

    Metabolic activity of the oral microbiota leads to acidification of the microenvironment and promotes demineralization of tooth structure at the margin of composite restorations. The pathogenic impact of the biofilm at the margin of the composite restoration could be reduced by engineering novel dentin adhesives that neutralize the acidic micro-environment. Integrating basic moieties into methacrylate derivatives has the potential to buffer against acid-induced degradation, and we are investi...

  11. Microbially mediated carbon mineralization: Geoengineering a carbon-neutral mine

    Science.gov (United States)

    Power, I. M.; McCutcheon, J.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2013-12-01

    Ultramafic and mafic mine tailings are a potentially valuable feedstock for carbon mineralization, affording the mining industry an opportunity to completely offset their carbon emissions. Passive carbon mineralization has previously been documented at the abandoned Clinton Creek asbestos mine, and the active Diavik diamond mine and Mount Keith nickel mine, yet the majority of tailings remain unreacted. Examples of microbe-carbonate interactions at each mine suggest that biological pathways could be harnessed to promote carbon mineralization. In suitable environmental conditions, microbes can mediate geochemical processes to accelerate mineral dissolution, increase the supply of carbon dioxide (CO2), and induce carbonate precipitation, all of which may accelerate carbon mineralization. Tailings mineralogy and the availability of a CO2 point source are key considerations in designing tailings storage facilities (TSF) for optimizing carbon mineralization. We evaluate the efficacy of acceleration strategies including bioleaching, biologically induced carbonate precipitation, and heterotrophic oxidation of waste organics, as well as abiotic strategies including enhancing passive carbonation through modifying tailings management practices and use of CO2 point sources (Fig. 1). With the aim of developing carbon-neutral mines, implementation of carbon mineralization strategies into TSF design will be driven by economic incentives and public pressure for environmental sustainability in the mining industry. Figure 1. Schematic illustrating geoengineered scenarios for carbon mineralization of ultramafic mine tailings. Scenarios A and B are based on non-point and point sources of CO2, respectively.

  12. Neutral Wind Observations below 200 km altitudes

    Science.gov (United States)

    Watanabe, S.; Abe, T.; Habu, H.; Kakinami, Y.; Larsen, M. F.; Pfaff, R. F., Jr.; Yamamoto, M.

    2015-12-01

    Neutral Wind Observations below 200 km altitudesS. Watanabe1, T. Abe2, H. Habu2, Y. Kakinami3, M. Larsen4, R. Pfaff5, M. Yamamoto6, M-Y. Yamamoto31Hokkaido University/Hokkaido Information University, 2JAXA/ISAS, 3Kochi University of Technology, 4Clemson University, 5NASA/Goddard Space Flight Center, 6Kyoto University, Neutral wind in the thermosphere is one of the key parameters to understand the ionosphere-thermosphere coupling process. JAXA/ISAS successfully launched sounding rockets from Uchinoura Space Center (USC) on September 2, 2007, January 12, 2012, and July 20, 2013, and NASA launched sounding rockets from Kwajalein on May 7, 2013 and from Wallops on July 4, 2013. The rockets installed Lithium and/or TMA canisters as well as instruments for plasma and electric and magnetic fields. The atomic Lithium gases were released at altitudes between 150 km and 300 km in the evening on September 2, 2007, at altitude of ~100 km in the morning on January 12, 2012, at altitude of ~120km in the midnight on July 20, 2013, at altitude between 150 km and 300 km in the evening on May 7, 2013 and at altitude of ~150 km in the noon on July 4, 2013. The Lithium atoms were scattering sunlight by resonance scattering with wavelength of 670nm. However, the Lithium atoms scattered moon light on July 20, 2013. The moon light scattering is the first time to use for thermospheric wind measurement in the midnight. The Lithium clouds/trails and TMA trails showed clearly the neutral wind shears and atmospheric waves at ~150 km altitude in the lower thermosphere for all local time.

  13. A Neutral Beam Injector Upgrade for NSTX

    Energy Technology Data Exchange (ETDEWEB)

    T. Stevenson; B McCormack; G.D. Loesser; M. Kalish; S. Ramakrishnan; L. Grisham; J. Edwards; M. Cropper; G. Rossi; A. von Halle; M. Williams

    2002-01-18

    The National Spherical Torus Experiment (NSTX) capability with a Neutral Beam Injector (NBI) capable of 80 kiloelectronvolt (keV), 5 Megawatt (MW), 5 second operation. This 5.95 million dollar upgrade reused a previous generation injector and equipment for technical, cost, and schedule reasons to obtain these specifications while retaining a legacy capability of 120 keV neutral particle beam delivery for shorter pulse lengths for possible future NSTX experiments. Concerns with NBI injection included power deposition in the plasma, aiming angles from the fixed NBI fan array, density profiles and beam shine through, orbit losses of beam particles, and protection of the vacuum vessel wall against beam impingement. The upgrade made use of the beamline and cryo panels from the Neutral Beam Test Stand facility, existing power supplies and controls, beamline components and equipment not contaminated by tritium during DT [deuterium-tritium] experiments, and a liquid Helium refrigerator plant to power and cryogenically pump a beamline and three ion sources. All of the Tokamak Fusion Test Reactor (TFTR) ion sources had been contaminated with tritium, so a refurbishment effort was undertaken on selected TFTR sources to rid the three sources destined for the NSTX NBI of as much tritium as possible. An interconnecting duct was fabricated using some spare and some new components to attach the beamline to the NSTX vacuum vessel. Internal vacuum vessel armor using carbon tiles was added to protect the stainless steel vacuum vessel from beam impingement in the absence of plasma and interlock failure. To date, the NBI has operated to 80 keV and 5 MW and has injected requested power levels into NSTX plasmas with good initial results, including high beta and strong heating characteristics at full rated plasma current.

  14. Scientists Explain Catalysis Neutralizing Car's Tail Gas

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The neutralization of the car's tail gas is a problem of practical importance in the eyes of both experimental and theoretical physicists. Recently, a group of CAS scientists join hands with the Queen's University of Belfast in the UK to make advances in exploring the process of CO oxidation in a bid to reduce the air pollution caused by the car's exhaust gas. The work has been supported by the "National 973Program" and the CAS Foundation for Overseas Studies. On March 4,its result was published by the Internet edition of the Journal of the American Chemical Society.

  15. The Columbia Non-neutral Torus

    International Nuclear Information System (INIS)

    Final report for the Columbia Non-neutral Torus. This details the results from the design, construction and initial operation of the Columbia Non-neutral Torus. During the duration of this grant, I designed, built, and operated the Columbia Nonneutral Torus, the world's lowest aspect ratio stellarator, and arguably, the world's simplest stellarator. This demonstrates the ease and robustness of the chosen stellarator design and allowed us to commence the investigation of the physics of non-neutral plasmas confined on magnetic surfaces. These plasmas are unique in many ways and had not previously been studied in a stellarator. Our first results showed that it is possible to confine and study a relatively cold pure electron plasma in a stellarator. We confirmed that the plasma is stable, and that the plasma is reasonably well confined in a stellarator configuration. These results were published in Physics of Plasmas (2006) and Physical Review Letters (2006). They enabled the existing program which is resolving the underlying transport processes in a classical stellarator with intense self-electric fields and enable the next phase of operation, electron-positron plasma physics. During the period of this grant, two students were trained in experimental plasma physics and both received their PhD degrees shortly after the grant terminated. One student is now employed in the financial services industry, the other is a postdoctoral associate at Los Alamos National Laboratory. The chief goals were to build and begin operation of the Columbia Non-neutral Torus. These goals were achieved in the third year of funding. The development of diagnostic methods and the confirmation of stable equilibria were also achieved during the grant period. In summary, the main scientific goals were all met. The main educational goals were also met, as the experiment became the training ground not only for the two aforementioned graduate students but also for a number of undergraduate students

  16. Neutral Atomic Carbon in Centers of Galaxies

    OpenAIRE

    Israel, F.P.; Baas, F

    2001-01-01

    We present measurements of the emission from the centers of fifteen spiral galaxies in the 3P1-3P0 [CI] fine-structure transition at 492 GHz. Observed galaxy centers range from quiescent to starburst to active. The intensities of neutral carbon, the J=2-1 transition of 13CO and the J=4-3 transition of 12CO are compared in matched beams. Most galaxy centers emit more strongly in [CI] than in 13CO, completely unlike the situation pertaining to Galactic molecular cloud regions. [CI] intensities ...

  17. Nuclear pumping of a neutral carbon laser

    International Nuclear Information System (INIS)

    Nuclear pumped lasing on the neutral carbon line at 1.45 μ has been achieved in mixtures of He-CO, He-CO2, Ne-CO and Ne-CO2. A low thermal neutron flux of 2 x 1014 n/cm2-sec was required and delays of up to 5.5 ms were observed. Helium pressures ranged from 20-800 T, Ne from 100-200 T, CO from 0.25 to 20 mT and CO2 from 0.1 to 25 mT

  18. The buffer effect in neutral electrolyte supercapacitors

    DEFF Research Database (Denmark)

    Thrane Vindt, Steffen; Skou, Eivind M.

    2016-01-01

    The observation that double-layer capacitors based on neutral aqueous electrolytes can have significantly wider usable potential windows than those based on acidic or alkaline electrolytes is studied. This effect is explained by a local pH change taking place at the electrode surfaces, leading to a...... of addition of a buffer to such systems. It is shown that a 56 % higher dynamic storage capacity may be achieved, simply by controlling the buffer capacity of the electrolyte. The model system used, is based on a well-known commercial activated carbon (NORIT™ A SUPRA) as the electrode material...

  19. Neutral atomic carbon in dense molecular clouds

    Science.gov (United States)

    Zmuidzinas, J.; Betz, A. L.; Boreiko, R. T.; Goldhaber, D. M.

    1988-01-01

    The 370 micron 3P2-3P1 fine-structure line of neutral carbon was detected in seven sources: OMC 1, NGC 2024, S140, W3, DR 21, M17, and W51. Simultaneous analysis of J = 2-1 data and available observations of the J = 1-0 line make it possible to deduce optical depths and excitation temperatures for these lines. These data indicate that both C I lines are likely to be optically thin, and that the ratio of C I to CO column densities in these clouds is typically about 0.1.

  20. Neutral Gas Plasma Interactions in Space Plasma

    Science.gov (United States)

    Liou, Kan

    A sounding rocket experiment, CRIT-II, involving the injection of shaped-charge barium in ionospheric plasma was conducted on May 7, 1989, to investigate Alfven's critical ionization velocity (CIV) hypothesis in space. The CRIT -II main payload was instrumented to make in situ measurements within the neutral barium beam. Among the detectors, UNH provided three energetic particle detectors and two photometers. The data from these detectors are presented. The typical features of the CIV effect were observed including plasma density enhancement, energy and momentum loss of a fast ion beam, excitation of plasma waves, and electron heating. It was found by optical observations that about 4% of the neutral barium was ionized. We believe that about one half of these barium ions were created by electron impact ionization --a CIV mechanism. The cross section for collisions between the barium atoms and the ionospheric oxygen ions was also calculated, assuming that the other half of ionizing barium ions were mainly generated by charge exchange, and found to be in the range from 1 times 10 ^{-17} cm^{-2} at a velocity of 4 km/s to 1 times 10^{-15} cm^{-2} at a velocity of 20 km/s. We also confirmed that the early observed ions were originally from the collisionally accelerated neutral oxygen which charge exchanges with the local oxygen ions. The early stage of electron heating was confirmed to be the result of lower hybrid instabilities excited by the precursor ion beam, using our quasi-linear model calculation. However, the wave spectrum during the passage of main streaming barium was found to be inconsistent with the lower hybrid instabilities proposed by current CIV theories. This could be the main reason for a relatively low ionization yield that one otherwise would expect from CRIT-II. A multi-fluid model of the wave dispersion relation for an unmagnetized beam with finite width in a magnetized plasma was also derived. We found that the nonuniform beam density effect