WorldWideScience

Sample records for epithermal neutral activation

  1. Epithermal Neutron Activation Analysis of the Asian Herbal Plants

    Science.gov (United States)

    Baljinnyam, N.; Jugder, B.; Norov, N.; Frontasyeva, M. V.; Ostrovnaya, T. M.; Pavlov, S. S.

    2011-06-01

    Asian medicinal herbs Chrysanthemum (Spiraea aquilegifolia Pall.) and Red Sandalwood (Pterocarpus Santalinus) are widely used in folk and Ayurvedic medicine for healing and preventing some diseases. The modern medical science has proved that the Chrysanthemum (Spiraea aquilegifolia Pall.) possesses the following functions: reducing blood press, dispelling cancer cell, coronary artery's expanding and bacteriostating and Red Sandalwood (Pterocarpus Santalinus) is recommended against headache, toothache, skin diseases, vomiting and sometimes it is taken for treatment of diabetes. Species of Chrysanthemums were collected in the north-eastern and central Mongolia, and the Red Sandalwood powder was imported from India. Samples of Chrysanthemums (branches, flowers and leaves) (0.5 g) and red sandalwood powder (0.5 g) were subjected to the multi-element instrumental neutron activation analysis using epithermal neutrons (ENAA) at the IBR-2 reactor, Frank Laboratory of Neutron Physics (FLNP) JINR, Dubna. A total of 41 elements (Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Cd, Cs, Ba, La, Hf, Ta, W, Sb, Au, Hg, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Th, U, Lu) were determined. For the first time such a large group of elements was determined in the herbal plants used in Mongolia. The quality control of the analytical results was provided by using certified reference material Bowen Cabbage. The results obtained are compared to the "Reference plant» data (B. Markert, 1992) and interpreted in terms of excess of such elements as Se, Cr, Ca, Fe, Ni, Mo, and rare earth elements.

  2. Possibilities of the short-term thermal and epithermal neutron activation for analysis of macromycetes (mushrooms)

    Czech Academy of Sciences Publication Activity Database

    Řanda, Zdeněk; Soukal, Ladislav; Mizera, Jiří

    2005-01-01

    Roč. 264, č. 1 (2005), s. 67-76 ISSN 0236-5731 R&D Projects: GA AV ČR IAA3048201 Institutional research plan: CEZ:AV0Z10480505 Keywords : neutron activation analysis * epithermal NAA * mushrooms * macromycetes Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 0.460, year: 2005

  3. Determination of rare earths and thorium in apatites by thermal and epithermal neutron-activation analysis.

    Science.gov (United States)

    Brunfelt, A O; Roelandts, I

    1974-06-01

    A procedure is described for the non-destructive determination of Na, Mn, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Lu and Th in apatites by thermal and epithermal neutron-activation of independent portions of the material. The method was applied to three apatites with different contents. The precision obtained was better than +/-5% for La, Ce, Sm, Eu, Gd, Tb and Dy and +/-20% for Yb, Nd, Ho, Er and Lu for an apatite with a total rare-earth oxide content of the order of 1%. Determination of Ce, Tb and Yb could only be carried out with thermal neutron-activation analysis, while Gd, Ho and Er could only be determined after irradiation with epithermal neutrons.

  4. EPITHERMAL NEUTRON ACTIVATION ANALYSIS FOR BACTERIAL TRANSFORMATIONS OF CHROMIUM

    Directory of Open Access Journals (Sweden)

    N.Ya. Tsibakhashvili

    2009-12-01

    Full Text Available Most powerful primary analytical technique, neutron activation analysis, was applied to study indigenous bacteria, namely, Arthrobacter genera which can be successfully used in detoxification and immobilization of toxic substances. In the present study the effect of Cr(VI on the elemental content of these bacteria has been examined. The concentrations from 12 to 19 elements such as Na, Al, Cl, K, Fe, Co, Zn, As, Br, Rb, Sr, Sb, Ba, Tb, Th, U were determined in the bacterial cells. The high rate of Cr accumulation in the tested bacterial cells was shown. In bacteria treated with chromate some similarity in the behaviour of the following essential elements − potassium, sodium, chlorine − was observed. Such non-essential elements as Ag, As, Br and U were determined in all bacteria and have to be considered by cells as toxins.

  5. Distribution of 35 Elements in Peat Cores from Ombrotrophic Bogs Studied by Epithermal Neutron Activation Analysis

    CERN Document Server

    Frontasyeva, M V

    2004-01-01

    In ombrotrophic bogs the surface peat layer is supplied with chemical substances only from the atmosphere. Peat cores from these bogs therefore can be used to study temporal trends in atmospheric deposition of pollutants. In this work epithermal neutron activation analysis was applied for the first time to study the distribution of 35 elements in peat profiles from ombrotrophic bogs. The selected examples were from Finnmark county in northern Norway: one pristine site far from any local pollution source, and another strongly affected by long-term operation of Russian copper-nickel smelters located close to the border. The elements are classified with respect to their behavior in the uppermost 40 cm of the peat, and similarities and differences between the two profiles are discussed. As compared with other more commonly used analytical techniques based on acid decomposition of the sample ENAA has the advantage of providing the total concentrations of the elements.

  6. Marine Gradients of Halogens in Moss Studied by Epithermal Neutron Activation Analysis

    CERN Document Server

    Frontasyeva, M V

    2002-01-01

    Epithermal neutron activation analysis is known to be a powerful technique for the simultaneous study of chlorine, bromine and iodine in environmental samples. In this paper it is shown to be useful to elucidate marine gradients of these elements. Examples are from a transect study in northern Norway where samples of the feather moss Hylocomium splendens were collected at distances 0-300 km from the coastline. All three elements decreased exponentially as a function of distance from the ocean in the moss samples, strongly indicating that atmospheric supply from the marine environment is the predominant source of these elements to the terrestrial ecosystem. These results are compared with similar data for surface soils along the same gradients. Comparison is also made with previous data for halogens in moss in Norway obtained by conventional NAA and covering similar transects in other geographical regions. The Cl/Br and Br/I ratios in moss showed a regular change distance from the ocean in all transects, and h...

  7. Determination of uranium in tree bark samples by epithermal neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Nicole Pereira de; Saiki, Mitiko, E-mail: mitiko@ipen.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    In this study uranium (U) concentrations were determined in certified reference materials (CRMs) and in tree bark samples collected in 'Cidade Universitaria Armando de Salles Oliveira' (CUASO) USP, Sao Paulo, SP, Brazil). The barks were collected from different species namely Poincianella pluviosa and Tipuana tipu. These bark samples were cleaned, dried, grated and milled for the analyses by epithermal neutron activation analysis method (ENAA). This method consists on irradiating samples and U standard in IEAR1 nuclear reactor with thermal neutron flux of 1:9 x 10{sup 12} n cm{sup -2} s{sup -1} during 40 to 60 seconds depending on the samples matrices. The samples and standard were measured by gamma ray spectroscopy. U was identified by the peak of 74.66 keV of {sup 239}U with half life of 23.47 minutes. Concentration of U was calculated by comparative method. For analytical quality control of U results, certified reference materials were analysed. Results obtained for CRMs presented good precision and accuracy, with |Z score| <= 0.39. Uranium concentrations in tree barks varied from 83.1 to 627.6 ng g{sup -} {sup 1} and the relative standard deviations of these results ranged from 1.8 to 10%. (author)

  8. Epithermal Neutron Activation Analysis (ENAA) of Cr(VI)-reducer Basalt-inhabiting Bacteria

    CERN Document Server

    Tsibakhashvili, N Ya; Kirkesali, E I; Aksenova, N G; Kalabegishvili, T L; Murusidze, I G; Mosulishvili, L M; Holman, H Y N

    2005-01-01

    Epithermal neutron activation analysis (ENAA) has been applied to studying elemental composition of Cr(VI)-reducer bacteria isolated from polluted basalts from the Republic of Georgia. Cr(VI)-reducing ability of the bacteria was examined by electron spin resonance (ESR) demonstrating that the bacteria differ in the rates of Cr(VI) reduction. A well-pronounced correlation between the ability of the bacteria to accumulate Cr(V) and their ability to reduce Cr(V) to Cr(III) observed in our experiments is discussed. Elemental analysis of these bacteria also revealed that basalt-inhabiting bacteria are distinguished by relative contents of essential elements such as K, Na, Mg, Fe, Mn, Zn, and Co. A high rate of Cr(III) formation correlates with a high concentration of Co in the bacterium. ENAA detected some similarity in the elemental composition of the bacteria. The relatively high contents of Fe detected in the bacteria (140-340 $\\mu $g/g of dry weight) indicate bacterial adaptation to the environmental condition...

  9. Epithermal Neutron Activation Analysis of Spirulina platensis Biomass, of the C-Phycocianin and of DNA Extracted from It

    CERN Document Server

    Mosulishvili, L M; Belokobylsky, A I; Kirkesali, E I; Khizanishvili, A I; Pomyakushina, E V

    2002-01-01

    The epithermal neutron activation analysis (ENAA) was used for study of the biomass of Spirulina platensis. The background levels of concentration 27 macro-, micro- and trace elements ranging from 10^{-3} up to 10^{4} ppm were determined. It was found that the biomass of spirulina does not contain toxic elements above the tolerance levels and can be utilized as a matrix of pharmaceuticals based on it. The concentrations of basic elements in C-phycocianin and DNA extracted from Spirulina platensis were determined by ENAA. A comparison of the element content of a whole spirulina biomass with that of a refined C-phycocianin preparation was made.

  10. Application of Epithermal Neutron Activation Analysis to Investigate Accumulation and Adsorption of Mercury by Spirulina platensis Biomass

    CERN Document Server

    Mosulishvili, L M; Khizanishvili, A I; Frontasyeva, M V; Kirkesali, E I; Aksenova, N G

    2004-01-01

    Epithermal neutron activation analysis was used to study interaction of blue-green alga Spirulina platensis with toxic metal mercury. Various concentrations of Hg(II) were added to cell cultures in a nutrient medium. The dynamics of accumulation of Hg was investigated over several days in relation to Spirulina biomass growth. The process of Hg adsorption by Spirulina biomass was studied in short-time experiments. The isotherm of adsorption was carried out in Freindlich coordinates. Natural Spirulina biomass has potential to be used in the remediation of sewage waters at Hg concentrations \\sim 100 {\\mu}g/l.

  11. Geochemistry of sediments and surface soils from the Nile Delta and lower Nile valley studied by epithermal neutron activation analysis

    Science.gov (United States)

    Arafa, Wafaa M.; Badawy, Wael M.; Fahmi, Naglaa M.; Ali, Khaled; Gad, Mohamed S.; Duliu, Octavian G.; Frontasyeva, Marina V.; Steinnes, Eiliv

    2015-07-01

    The distributions of 36 major and trace elements in 40 surface soil and sediment samples collected from the Egyptian section of the river Nile were determined by epithermal neutron activation analysis and compared with corresponding data for the Upper Continental Crust and North American Shale Composite. Their relative distributions indicate the presence of detrital material of igneous origin, most probably resulting from weathering on Ethiopian highlands and transported by the Blue Nile, the Nile main tributary. The distributions of the nickel, zinc, and arsenic contents suggest that the lower part of the Nile and its surroundings including the Nile Delta is not seriously polluted with metals from local human activity. The geographical distributions of Na, Cl, and I as well as results of principal component analysis suggest atmospheric supply of these elements from the ocean. In general the present data may contribute to a better understanding of the geochemistry of the Nile sediments.

  12. Multiple episodes of hydrothermal activity and epithermal mineralization in the southwestern Nevada volcanic field and their relations to magmatic activity, volcanism and regional extension

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, S.I.; Noble, D.C.; Jackson, M.C. [Univ. of Nevada, Reno, NV (United States)] [and others

    1994-12-31

    Volcanic rocks of middle Miocene age and underlying pre-Mesozoic sedimentary rocks host widely distributed zones of hydrothermal alteration and epithermal precious metal, fluorite and mercury deposits within and peripheral to major volcanic and intrusive centers of the southwestern Nevada volcanic field (SWNVF) in southern Nevada, near the southwestern margin of the Great Basin of the western United States. Radiometric ages indicate that episodes of hydrothermal activity mainly coincided with and closely followed major magmatic pulses during the development of the field and together spanned more than 4.5 m.y. Rocks of the SWNVF consist largely of rhyolitic ash-flow sheets and intercalated silicic lava domes, flows and near-vent pyroclastic deposits erupted between 15.2 and 10 Ma from vent areas in the vicinity of the Timber Mountain calderas, and between about 9.5 and 7 Ma from the outlying Black Mountain and Stonewall Mountain centers. Three magmatic stages can be recognized: the main magmatic stage, Mountain magmatic stage (11.7 to 10.0 Ma), and the late magmatic stage (9.4 to 7.5 Ma).

  13. Different Activation Techniques for the Study of Epithermal Spectra, Applied to Heavy Water Lattices of Varying Fuel-To-Moderator Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Sokolowski, E.K.

    1966-06-15

    Spectral indices at the cell boundary have been studied as functions of lattice pitch in the reference core of the Swedish R0 reactor. Epithermal indices were determined by activation of In{sup 115}, employing three different techniques: the two-foil, the cadmium ratio and the sandwich foil methods. The latter of these has the advantage of being independent of assumptions about foil cross sections or spectral functions, and it gives a spectrum index that lends itself readily to comparisons with theoretical multigroup calculations. Alternatively the results can be expressed in terms of the Westcott parameters r and T{sub n} when this is justified by the spectral conditions. The agreement between the three methods investigated is generally good. Good agreement is also found with multigroup collision.

  14. Effect of epithermal neutrons on viability of glioblastoma tumor cells in vitro.

    Science.gov (United States)

    Mostovich, L A; Gubanova, N V; Kutsenko, O S; Aleinik, V I; Kuznetsov, A S; Makarov, A N; Sorokin, I N; Taskaev, S Yu; Nepomnyashchikh, G I; Grigor'eva, E V

    2011-06-01

    We studied in vitro effect of epithermal neutrons in various doses on viability of glioblastoma U87 tumor cells. Increasing the dose from 1.9 to 4.1 Sv promoted cell death. Cytofluorimetric analysis revealed no activation of apoptosis in the irradiated cells, which attested to necrotic death of the tumor cells exposed to epithermal neutron radiation.

  15. Determination of the thermal and epithermal neutron sensitivities of an LBO chamber

    Energy Technology Data Exchange (ETDEWEB)

    Endo, Satoru; Kotani, Kei; Kajimoto, Tsuyoshi; Tanaka, Kenichi [Hiroshima University, Quantum Energy Applications, Graduate School of Engineering, Higashi-Hiroshima (Japan); Sato, Hitoshi; Nakajima, Erika [Ibaraki Prefectural University of Health Science, Radiological Sciences, Ibaraki (Japan); Shimazaki, Takuto [Hiroshima University, Quantum Energy Applications, Graduate School of Engineering, Higashi-Hiroshima (Japan); Delta Kogyo Co., Ltd., Hiroshima (Japan); Suda, Mitsuru; Hamano, Tsuyoshi [National Institute of Radiological Sciences, Chiba-Shi, Chiba (Japan); Hoshi, Masaharu [Hiroshima University, Institute for Peace Science, Hiroshima (Japan)

    2017-08-15

    An LBO (Li{sub 2}B{sub 4}O{sub 7}) walled ionization chamber was designed to monitor the epithermal neutron fluence in boron neutron capture therapy clinical irradiation. The thermal and epithermal neutron sensitivities of the device were evaluated using accelerator neutrons from the {sup 9}Be(d, n) reaction at a deuteron energy of 4 MeV (4 MeV d-Be neutrons). The response of the chamber in terms of the electric charge induced in the LBO chamber was compared with the thermal and epithermal neutron fluences measured using the gold-foil activation method. The thermal and epithermal neutron sensitivities obtained were expressed in units of pC cm{sup 2}, i.e., from the chamber response divided by neutron fluence (cm{sup -2}). The measured LBO chamber sensitivities were 2.23 x 10{sup -7} ± 0.34 x 10{sup -7} (pC cm{sup 2}) for thermal neutrons and 2.00 x 10{sup -5} ± 0.12 x 10{sup -5} (pC cm{sup 2}) for epithermal neutrons. This shows that the LBO chamber is sufficiently sensitive to epithermal neutrons to be useful for epithermal neutron monitoring in BNCT irradiation. (orig.)

  16. Determination of the thermal and epithermal neutron sensitivities of an LBO chamber.

    Science.gov (United States)

    Endo, Satoru; Sato, Hitoshi; Shimazaki, Takuto; Nakajima, Erika; Kotani, Kei; Suda, Mitsuru; Hamano, Tsuyoshi; Kajimoto, Tsuyoshi; Tanaka, Kenichi; Hoshi, Masaharu

    2017-08-01

    An LBO (Li2B4O7) walled ionization chamber was designed to monitor the epithermal neutron fluence in boron neutron capture therapy clinical irradiation. The thermal and epithermal neutron sensitivities of the device were evaluated using accelerator neutrons from the (9)Be(d, n) reaction at a deuteron energy of 4 MeV (4 MeV d-Be neutrons). The response of the chamber in terms of the electric charge induced in the LBO chamber was compared with the thermal and epithermal neutron fluences measured using the gold-foil activation method. The thermal and epithermal neutron sensitivities obtained were expressed in units of pC cm(2), i.e., from the chamber response divided by neutron fluence (cm(-2)). The measured LBO chamber sensitivities were 2.23 × 10(-7) ± 0.34 × 10(-7) (pC cm(2)) for thermal neutrons and 2.00 × 10(-5) ± 0.12 × 10(-5) (pC cm(2)) for epithermal neutrons. This shows that the LBO chamber is sufficiently sensitive to epithermal neutrons to be useful for epithermal neutron monitoring in BNCT irradiation.

  17. Cs-137 geochronology, epithermal neutron activation analysis, and principal component analysis of heavy metals pollution of the Black Sea anoxic continental shelf sediments

    Science.gov (United States)

    Duliu, O. G.; Cristache, C.; Oaie, G.; Culicov, O. A.; Frontasyeva, M. V.

    2009-04-01

    Anthropogenic Cs-137 Gamma-ray Spectroscopy assay (GrSA) performed at the National Institute of Research and Development for Physics and Nuclear Engineering - Bucharest (Romania) in correlation with Epithermal Neutrons Activation Analysis (ENAA) performed at the Joint Institute of Nuclear Researches - Dubna (Russia) were used to investigate a 50 cm core containing unconsolidated sediments collected at a depth of 600 m off Romanian town of Constantza, located in the anoxic zone of the Black Sea Continental Shelf. A digital radiography showed the presence of about 265 distinct laminae, 1 to 3 mm thick, a fact attesting a stationary sedimentary process, completely free of bioturbation. After being radiographed, the core was sliced into 45 segments whose thickness gradually increased from 0.5 to 5 cm, such that the minimum thickness corresponded to the upper part of the core. From each segment two aliquots of about 0.5 g and 50 g were extracted for subsequent ENAA and Cs-137 GrSA. The Cs-137 vertical profile evidenced two maxima, one of them was very sharp and localized at a depth of 1 cm and the other very broad, almost undistinguished at about 8 cm depth, the first one being attributed to 1986 Chernobyl accident. Based on these date, we have estimated a sedimentation ratio of about 0.5 mm/year, value taken as reference for further assessment of recent pollution history. By means of ENAA we have determined the vertical content of five presumed pollutants, e.i. Zn, As, Br, Sn and Sb and of Sc, as natural, nonpolluting element. In the first case, all five elements presented a more or less similar vertical profile consisting of an almost exponential decrease for the first 10 cm below sediment surface followed by a plateau until the core base, i.e. 50 cm below surface, dependency better described by the equation: c(z) = c0 [1+k exp (-z/Z)] (1) where: where c(z) represents the concentration vertical profile; z represents depth (in absolute value); c0 represents the plateau

  18. Geology of the Ivanhoe Hg-Au district, northern Nevada: Influence of Miocene volcanism, lakes, and active faulting on epithermal mineralization

    Science.gov (United States)

    Wallace, A.R.

    2003-01-01

    massive rhyolites and Paleozoic quartzites at deeper levels, and these mineralized zones possibly represent the feeder zones for the higher-level deposits. Fluctuations in the ground-water table locally produced hydrothermal oxidation of the near-surface mercury and disseminated gold deposits. The locus of mineralization shifted with time, moving south and east from its inception point in the west-central part of the district. Thus, although mineralization in the district took place during a span of 300,000 years, the duration of mineralization at any one place probably was much shorter. The low-sulfidation deposits of the Ivanhoe district formed at the same time and under similar conditions as those in the nearby Midas district, 15 km to the northwest, which includes the large, high-grade Ken Snyder gold-silver epithermal vein deposit. The exposures in the Ivanhoe district are interpreted to represent the near-surface example of the paleosurface that originally was present above the Midas mineralizing system. The resulting combined Ivanhoe-Midas model provides an exploration guide for epithermal deposits in similar geologic environments in northern Nevada.

  19. Production of epithermal neutron beams for BNCT

    CERN Document Server

    Bisceglie, E; Colonna, N; Paticchio, V; Santorelli, P; Variale, V

    2002-01-01

    The use of boron neutron capture therapy (BNCT) for the treatment of deep-seated tumors requires neutron beams of suitable energy and intensity. Simulations indicate the optimal energy to reside in the epithermal region, in particular between 1 and 10 keV. Therapeutic neutron beams with high spectral purity in this energy range could be produced with accelerator-based neutron sources through a suitable neutron-producing reaction. Herein, we report on different solutions that have been investigated as possible sources of epithermal neutron beams for BNCT. The potential use of such sources for a hospital-based therapeutic facility is discussed.

  20. Modeling the LPS neutralization activity of anti-endotoxins.

    Science.gov (United States)

    Thippakorn, Chadinee; Suksrichavalit, Thummaruk; Nantasenamat, Chanin; Tantimongcolwat, Tanawut; Isarankura-Na-Ayudhya, Chartchalerm; Naenna, Thanakorn; Prachayasittikul, Virapong

    2009-05-20

    Bacterial lipopolysaccharides (LPS), also known as endotoxins, are major structural components of the outer membrane of Gram-negative bacteria that serve as a barrier and protective shield between them and their surrounding environment. LPS is considered to be a major virulence factor as it strongly stimulates the secretion of pro-inflammatory cytokines which mediate the host immune response and culminating in septic shock. Quantitative structure-activity relationship studies of the LPS neutralization activities of anti-endotoxins were performed using charge and quantum chemical descriptors. Artificial neural network implementing the back-propagation algorithm was selected for the multivariate analysis. The predicted activities from leave-one-out cross-validation were well correlated with the experimental values as observed from the correlation coefficient and root mean square error of 0.930 and 0.162, respectively. Similarly, the external testing set also yielded good predictivity with correlation coefficient and root mean square error of 0.983 and 0.130. The model holds great potential for the rational design of novel and robust compounds with enhanced neutralization activity.

  1. Modeling the LPS Neutralization Activity of Anti-Endotoxins

    Directory of Open Access Journals (Sweden)

    Virapong Prachayasittikul

    2009-05-01

    Full Text Available Bacterial lipopolysaccharides (LPS, also known as endotoxins, are major structural components of the outer membrane of Gram-negative bacteria that serve as a barrier and protective shield between them and their surrounding environment. LPS is considered to be a major virulence factor as it strongly stimulates the secretion of pro-inflammatory cytokines which mediate the host immune response and culminating in septic shock. Quantitative structure-activity relationship studies of the LPS neutralization activities of anti-endotoxins were performed using charge and quantum chemical descriptors. Artificial neural network implementing the back-propagation algorithm was selected for the multivariate analysis. The predicted activities from leave-one-out cross-validation were well correlated with the experimental values as observed from the correlation coefficient and root mean square error of 0.930 and 0.162, respectively. Similarly, the external testing set also yielded good predictivity with correlation coefficient and root mean square error of 0.983 and 0.130. The model holds great potential for the rational design of novel and robust compounds with enhanced neutralization activity.

  2. Active spectroscopy upgrades and neutral beam injection on LTX- β

    Science.gov (United States)

    Elliott, Drew; Biewer, Theodore; Canik, John; Reinke, Matthew; Bell, Ronald; Boyle, Dennis; Guttenfelder, Walter; Kaita, Robert; Kozub, Thomas; Majeski, Richard; Merino, Enrique

    2017-10-01

    The LTX- β upgrade includes the addition of neutral beam injection (NBI) and increased active spectroscopy. Typical plasmas have been and are expected to remain inboard limited, at 14 cm with minor radii of 18-23 cm. The NBI, 35 Amps of 20 keV particles, will enable active diagnosis of ion velocity distribution profiles through charge exchange (CHERS). 18 CHERS views will cover more than a full minor radius, each sampling 2 cm of major radius. The system has both a set of beam directed ``active'' views and a symmetric set of views pointing away from the beam for stray light subtraction. Along with measuring ion temperatures and impurity transport, the CHERS diagnostic will measure the plasma rotation profiles. The recently described low recycling regime is predicted to allow for high rotational velocities due to the low neutral drag. The planned NBI has been predicted to give on axis velocities near 100 km/s. Flow shear is expected to increase confinement in this regime by suppressing trapped electron mode and other microturbulence enhanced transport. Upgrades to the Thomson scattering system, including an array of polychromators and a new camera, will assist in diagnosing the low density hot edge in this low recycling regime. Supported by US DOE contracts DE-AC02-09CH11466 and DE-AC05-00OR22725.

  3. Critical elements in Carlin, epithermal, and orogenic gold deposits

    Science.gov (United States)

    Goldfarb, Richard J.; Hofstra, Albert H.; Simmons, Stuart F.

    2016-01-01

    Carlin, epithermal, and orogenic gold deposits, today mined almost exclusively for their gold content, have similar suites of anomalous trace elements that reflect similar low-salinity ore fluids and thermal conditions of metal transport and deposition. Many of these trace elements are commonly referred to as critical or near-critical elements or metals and have been locally recovered, although typically in small amounts, by historic mining activities. These elements include As, Bi, Hg, In, Sb, Se, Te, Tl, and W. Most of these elements are now solely recovered as by-products from the milling of large-tonnage, base metal-rich ore deposits, such as porphyry and volcanogenic massive sulfide deposits.A combination of dominance of the world market by a single country for a single commodity and a growing demand for many of the critical to near-critical elements could lead to future recovery of such elements from select epithermal, orogenic, or Carlin-type gold deposits. Antimony continues to be recovered from some orogenic gold deposits and tellurium could potentially be a primary commodity from some such deposits. Tellurium and indium in sphalerite-rich ores have been recovered in the past and could be future commodities recovered from epithermal ores. Carlin-type gold deposits in Nevada are enriched in and may be a future source for As, Hg, Sb, and/or Tl. Some of the Devonian carbonaceous host rocks in the Carlin districts are sufficiently enriched in many trace elements, including Hg, Se, and V, such that they also could become resources. Thallium may be locally enriched to economic levels in Carlin-type deposits and it has been produced from Carlin-like deposits elsewhere in the world (e.g., Alsar, southern Macedonia; Lanmuchang, Guizhou province, China). Mercury continues to be recovered from shallow-level epithermal deposits, as well as a by-product of many Carlin-type deposits where refractory ore is roasted to oxidize carbon and pyrite, and mercury is then

  4. Electric-current Neutralization, Magnetic Shear, and Eruptive Activity in Solar Active Regions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yang; Sun, Xudong [W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305-4085 (United States); Török, Tibor; Titov, Viacheslav S. [Predictive Science Inc., 9990 Mesa Rim Road, Suite 170, San Diego, CA 92121 (United States); Leake, James E. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2017-09-01

    The physical conditions that determine whether or not solar active regions (ARs) produce strong flares and coronal mass ejections (CMEs) are not yet well understood. Here, we investigate the association between electric-current neutralization, magnetic shear along polarity inversion lines (PILs), and eruptive activity in four ARs: two emerging and two well-developed ones. We find that the CME-producing ARs are characterized by a strongly non-neutralized total current, while the total current in the ARs that did not produce CMEs is almost perfectly neutralized. The difference in the PIL shear between these two groups is much less pronounced, which suggests that the degree of current neutralization may serve as a better proxy for assessing the ability of ARs to produce CMEs.

  5. Fast and epithermal neutron radiography using neutron irradiator

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Karol A.M. de; Crispim, Verginia R., E-mail: amon@ufrrj.br, E-mail: vrcrispim@gmail.com [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil).Programa de Engenharia Nuclear; Ferreira, Francisco J.O., E-mail: francisco@ien.br [Instituto de Energia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Divisao de Reatores

    2013-07-01

    The neutron radiography technique (NR) with neutrons in the energy range fast to epithermal is a powerful tool used in no-destructive inspection of bulky objects of diverse materials, including those rich in hydrogen, oxygen, nitrogen ad carbon. Thus, it can be used to identify, inclusions, voids and thickness differences in materials such as explosive artifacts and narcotics. Aiming at using NR with fast and epithermal neutrons, an Irradiator was constructed by: a {sup 241}Am-Be source, with 5 Ci activity, a collimator with adjustable collimation rate, L/D; and a shield device composed by plates of borated paraffin and iron. The test specimens chosen were a Beam Purity Indicator (BPI) and an Indicator of Visual Resolution (IVR). The neutron radiography images obtained had a resolution of 444.4 μm and 363.6 μm respectively when registered in: 1) the sheet of the nuclear track solid detector, CR-39 type, through X (n,p) Y nuclear reaction; and 2) Kodak Industrex M radiographic film plate in close contact with a boron converter screen, both stored in a Kodak radiographic cassette. (author)

  6. Evaluation for activities of component of Cyclotron-Based Epithermal Neutron Source (C-BENS) and the surface of concrete wall in irradiation room.

    Science.gov (United States)

    Imoto, M; Tanaka, H; Fujita, K; Mitsumoto, T; Ono, K; Maruhashi, A; Sakurai, Y

    2011-12-01

    The workers employed in BNCT must enter the irradiation room just after an irradiation under the condition of remaining activities. To reduce the radiation exposure for the workers, it is important to identify the origins of the activities. In this research, the activities induced on the concrete wall surface were evaluated using MCNP-5 and the measurement results of thermal neutron distribution. Furthermore, the radioisotopes produced in the moderator were identified with a High Purity Germanium detector. It was found that the activities of the wall were mainly caused by (46)Sc, (60)Co and (152)Eu, and that (24)Na and (56)Mn were mainly produced in the moderator. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Epithermal Neutron Evidence for a Diurnal Surface Hydration Process in the Moon's High Latitudes

    Science.gov (United States)

    McClanahan, T. P.; Mitrofanov, I. G.; Boynton, W. V.; Chin, G.; Parsons, A.; Starr, R. D.; Evans, L. G.; Sanin, A.; Litvak, M.; Livengood, T.

    2015-01-01

    We report evidence from epithermal neutron flux observations that show that the Moon's high latitude surfaces are being actively hydrated, dehydrated and rehydrated in a diurnal cycle. The near-surface hydration is indicated by an enhanced suppression of the lunar epithermal neutron leakage flux on the dayside of the dawn terminator on poleward-facing slopes (PFS). At 0600 to 0800 local-time, hydrogen concentrations within the upper 1 meter of PFS are observed to be maximized relative to equivalent equator-facing slopes (EFS). During the lunar day surface hydrogen concentrations diminish towards dusk and then rebuild overnight. Surface hydration is determined by differential comparison of the averaged EFS to PFS epithermal neutron count rates above +/- 75 deg latitude. At dawn the contrast bias towards PFS is consistent with at least 15 to 25 parts-per-million (ppm) hydrogen that dissipates by dusk. We review several lines of evidence derived from temperature and epithermal neutron data by a correlated analysis of observations from the Lunar Reconnaissance Orbiter's (LRO) Lunar Exploration Neutron Detector (LEND) that were mapped as a function of lunar local-time, Lunar Observing Laser Altimeter (LOLA) topography and Diviner (DLRE) surface temperature.

  8. Epithermal gold occurrences in the lakes district of the Main ...

    African Journals Online (AJOL)

    The overall characteristics of the known ore occurrences and the evolution of the Quaternary central volcanoes within the MER, and related epithermal processes seem to delineate an individual, homogeneous metallogenic province. A new field of investigation on epithermal ore occurrences which are unusual for the ...

  9. Permeability enhancement during gold mineralization: Evidences from Kestanelik epithermal vein system, NW Turkey

    Science.gov (United States)

    Gulyuz, Nilay; Shipton, Zoe; Kuscu, Ilkay; Lord, Richard A.; Gladwell, David R.; Kaymakci, Nuretdin

    2016-04-01

    aims to construct the 3D geometry of the major veins to see how the geometries of the veins relate to host rocks and gold grades and to help understand the structural controls on the vein emplacement and the likely evolution of the vein system. Our results suggest that after sealing of the veins due to the previous mineralization phases, permeability was created by earthquake rupturing event due to horizontal NE-SW-oriented compression dominant in the area during epithermal mineralization. Structures hosting the mineralized veins should have been activated along the vein-host rock contact in this compressional regime; E-W-oriented veins were opened as left lateral strike slip fault, N-S-oriented vein was opened as right lateral strike slip fault and NE-SW-oriented veins were opened as extensional fracture. Two phases of fluid flow and associated mineralization were picked up from E-W-oriented veins while four were determined from more dilatational NE-SW veins. This study emphasizes the importance of understanding the structural controls on the multi-event history of vein emplacement for gold exploration on the mine and regional scales. In addition, the results will shed light on the behaviour of hydrothermal fluids at high crustal levels.

  10. Physics of epi-thermal boron neutron capture therapy (epi-thermal BNCT).

    Science.gov (United States)

    Seki, Ryoichi; Wakisaka, Yushi; Morimoto, Nami; Takashina, Masaaki; Koizumi, Masahiko; Toki, Hiroshi; Fukuda, Mitsuhiro

    2017-12-01

    The physics of epi-thermal neutrons in the human body is discussed in the effort to clarify the nature of the unique radiologic properties of boron neutron capture therapy (BNCT). This discussion leads to the computational method of Monte Carlo simulation in BNCT. The method is discussed through two examples based on model phantoms. The physics is kept at an introductory level in the discussion in this tutorial review.

  11. Neutralization of Electric Current, Magnetic Shear, and Eruptive Activity in Solar Active Regions

    Science.gov (United States)

    Liu, Yang; Sun, Xudong; Torok, Tibor; Titov, Viacheslav; Leake, James E.

    2017-08-01

    There has been an ongoing debate on whether or not the electric currents in solar active regions (ARs) are neutralized. Current-neutralization means that the direct coronal currents that connect the AR polarity centers are surrounded by return currents of equal total strength and opposite direction, i.e. the net current is zero. Using data from SDO/HMI, we analyze the direct and return currents in four ARs; two eruptive ones and two non-eruptive ones. The eruptive ARs produced strong flares and CMEs (successful eruptions), while the non-eruptive ARs include one quiet AR that produced no strong eruptions and one that produced a series of failed eruptions. It is found that the eruptive ARs have strong net currents and large shear of the magnetic field near their polarity inversion lines (PILs). In contrast, the currents in the non-eruptive ARs are well neutralized, and the PIL-shear is rather small. This agrees with MHD simulations that demonstrate a relationship between the level of current neutralization and the amount of magnetic shear near the PIL. We discuss the implications of these results for the capability of ARs to produce strong eruptions.

  12. Formation and Aggregation of Gold (Electrum) Nanoparticles in Epithermal Ores

    OpenAIRE

    James A. Saunders; Michelle Burke

    2017-01-01

    Here, we review the concept that nanoparticles and colloids may have played a significant role in forming some types of hydrothermal ores deposits, particularly epithermal. This concept was first proposed almost a century ago but the development of new analytical technologies, lab experiments, and the discovery of new epithermal deposits where nanoparticles are evident have added credence to the “gold colloid theory”. Nanoparticles are defined to have at least one dimension <10−7 m, and ma...

  13. Enhanced plastic neutron shielding for thermal and epithermal neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Palomino, L A RodrIguez; Blostein, J J; Dawidowski, J [Consejo Nacional de Investigaciones CientIficas y Tecnicas, Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de EnergIa Atomica, Universidad Nacional de Cuyo, (8400) Bariloche, Av. Bustillo 9500, S. C. de Bariloche, RIo Negro (Argentina); Cuello, G J [Institut Laue Langevin, 6, rue Jules Horowitz, F-38042 Grenoble Cedex 9 (France)], E-mail: javier@cab.cnea.gov.ar

    2008-06-15

    We describe a compound made of paraffin and boron carbide (boraffin) deviced to enhance epithermal neutron shielding. The compound is easily prepared and is specially suited to be adapted to particular surfaces. Transmission experiments show a favourable comparison with a commercial rubber-boron carbide compound in the epithermal range. A detector shielding built with this material is described and the achieved background reduction experimentally determined is shown.

  14. EL4 cell-based colorimetric toxin neutralization activity assays for determination of neutralizing anti-ricin antibodies.

    Science.gov (United States)

    Lindsey, Changhong Y; Brown, J Edward; Torabazar, Nahid R; Smith, Leonard A

    2013-01-01

    A recombinant ricin toxin A-chain 1-33/44-198 vaccine (RVEc), developed at the United States Army Medical Research Institute of Infectious Diseases as a vaccine candidate, is under investigation in a phase 1 clinical study. To effectively evaluate the immunogenicity of this ricin vaccine and to eliminate the use of radioactive material, an EL4 cell-based colorimetric toxin neutralization activity (TNA) assay using a CellTiter 96 AQueous One Solution Cell Proliferation Assay Reagent has been developed, optimized, and applied in the vaccine efficacy studies. The TNA assay measures the protective neutralizing anti-ricin antibodies in animal sera by determining the cell viability after ricin exposure in the assay system and comparing it to a purified mouse polyclonal antiricin IgG standard curve. The standard curve of the anti-ricin TNA assay closely fits a four-parameter logistic regression model. The unknown test sample concentration was expressed as microg/mL, but not the 50% effective concentration (EC50), which was determined by most TNA assays. The neutralizing endpoint titers, not the 50% effective dilution (ED50), of human specimens were measured with the TNA assay in support of the clinical study of the RVEc vaccine. The optimal amount of ricin toxin, EL4 cells, and concentration of standards used in the assay system was established to minimize false-negative and false-positive results of serum specimens from the nonclinical and clinical studies of RVEc. The testing conditions were adjusted to optimize assay performance. The colorimetric TNA assay replaced a radioactive TNA assay previously used in the ricin vaccine studies.

  15. Geologic and tectonic setting of Deseado Massif epithermal deposits, Argentina, based on El Dorado-Monserrat

    Science.gov (United States)

    Echavarría, Leandro E.; Schalamuk, Isidoro B.; Etcheverry, Ricardo O.

    2005-09-01

    Middle-Late Jurassic bimodal volcanism, typical of a retroarc setting, developed during widespread extensional tectonism within the Deseado Massif, southern Argentina. This geologic environment led to the formation of numerous low-sulfidation epithermal deposits that are spatially and temporally related to the volcanic activity. The lack of significant high-sulfidation epithermal deposits may be because the tectonic and volcanic settings do not favor the formation of these types of deposits. El Dorado-Monserrat is a low-sulfidation epithermal prospect located near the southern boundary of the Deseado Massif. Mineralization is genetically linked to the Late Jurassic Chon Aike Formation and hosted by volcanic rocks of the middle Late Jurassic Bajo Pobre Formation. Two different mineralization areas have been identified. The Monserrat area is the most important, with veins hosted in a north-striking, left-lateral shear zone. The average thickness is 0.85 m, and the average metal content is 6.2 ppm gold and 153 ppm silver. The El Dorado area has discontinuous echelon veins within a right-lateral shear zone with low gold and silver grades. Hydrothermal alteration of the host rocks includes an inner zone of quartz-adularia and illite alteration and an outer zone of propylitic alteration. The main gangue mineral is quartz, which formed in successive pulses, plus adularia, pyrite, hematite, magnetite, and barite. Precious metals occur as zoned electrum. Ore mineral precipitation took place between 200 and 280 °C from low salinity fluids due to boiling.

  16. Promoting Active Species Generation by Electrochemical Activation in Alkaline Media for Efficient Electrocatalytic Oxygen Evolution in Neutral Media.

    Science.gov (United States)

    Xu, Kun; Cheng, Han; Liu, Linqi; Lv, Haifeng; Wu, Xiaojun; Wu, Changzheng; Xie, Yi

    2017-01-11

    In this study, by using dicobalt phosphide nanoparticles as precatalysts, we demonstrated that electrochemical activation of metallic precatalysts in alkaline media (comparing with directly electrochemical activation in neutral media) could significantly promote the OER catalysis in neutral media, specifically realizing a 2-fold enhanced activity and meanwhile showing a greatly decreased overpotential of about 100 mV at 10 mA cm(-2). Compared directly with electrochemical activation in neutral media, the electrochemical activation in harsh alkaline media could easily break the strong Co-Co bond and promote active species generation on the surface of metallic Co2P, thus accounting for the enhancement of neutral OER activity, which is also evidenced by HRTEM and the electrochemical double-layer capacitance measurement. The activation of electrochemical oxidation of metallic precatalysts in alkaline media enhanced neutral OER catalysis could also be observed on CoP nanoparticles and Ni2P nanoparticles, suggesting this is a generic strategy. Our work highlights that the activation of electrochemical oxidation of metallic precatalysts in alkaline media would pave new avenues for the design of advanced neutral OER electrocatalysts.

  17. Formation and Aggregation of Gold (Electrum Nanoparticles in Epithermal Ores

    Directory of Open Access Journals (Sweden)

    James A. Saunders

    2017-09-01

    Full Text Available Here, we review the concept that nanoparticles and colloids may have played a significant role in forming some types of hydrothermal ores deposits, particularly epithermal. This concept was first proposed almost a century ago but the development of new analytical technologies, lab experiments, and the discovery of new epithermal deposits where nanoparticles are evident have added credence to the “gold colloid theory”. Nanoparticles are defined to have at least one dimension <10−7 m, and may have different chemical and physical properties than the bulk solids. Colloids are typically <10−6 m in diameter and have the added characteristic that they are dispersed in another medium. In epithermal ore-forming solutions, gold or electrum nanoparticles nucleate from supersaturated hydrothermal solutions, and thus this is a “far-from-equilibrium” process. In some cases, gold nanoparticles may simply play a transitory role of aggregating to form much coarser-grained crystals, where all of the evidence of nanoparticles precursor phases is not preserved. However, in some epithermal ores, silica nanoparticles also formed, and their co-deposition with gold (electrum nanoparticles preserved the gold aggregation features as self-organized “fractal” dendrites. Here, we review existing the data on gold and electrum nanoparticles in epithermal ores, present images of electrum nanoparticles and their aggregates, and discuss the significance of gold nanoparticles formation and aggregation in helping to produce some of the highest-grade gold ores in the world.

  18. 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

  19. Non-neutralized Electric Currents in Solar Active Regions and Flare Productivity

    Science.gov (United States)

    Kontogiannis, Ioannis; Georgoulis, Manolis K.; Park, Sung-Hong; Guerra, Jordan A.

    2017-11-01

    We explore the association of non-neutralized currents with solar flare occurrence in a sizable sample of observations, aiming to show the potential of such currents in solar flare prediction. We used the high-quality vector magnetograms that are regularly produced by the Helioseismic Magnetic Imager, and more specifically, the Space weather HMI Active Region Patches (SHARP). Through a newly established method that incorporates detailed error analysis, we calculated the non-neutralized currents contained in active regions (AR). Two predictors were produced, namely the total and the maximum unsigned non-neutralized current. Both were tested in AR time-series and a representative sample of point-in-time observations during the interval 2012 - 2016. The average values of non-neutralized currents in flaring active regions are higher by more than an order of magnitude than in non-flaring regions and correlate very well with the corresponding flare index. The temporal evolution of these parameters appears to be connected to physical processes, such as flux emergence and/or magnetic polarity inversion line formation, that are associated with increased solar flare activity. Using Bayesian inference of flaring probabilities, we show that the total unsigned non-neutralized current significantly outperforms the total unsigned magnetic flux and other well-established current-related predictors. It therefore shows good prospects for inclusion in an operational flare-forecasting service. We plan to use the new predictor in the framework of the FLARECAST project along with other highly performing predictors.

  20. Performance verification of an epithermal neutron flux monitor using accelerator-based BNCT neutron sources

    Science.gov (United States)

    Guan, X.; Murata, I.; Wang, T.

    2017-09-01

    The performance of an epithermal neutron flux monitor developed for boron neutron capture therapy (BNCT) is verified by Monte Carlo simulations using accelerator-based neutron sources (ABNSs). The results indicate that the developed epithermal neutron flux monitor works well and it can be efficiently used in practical applications to measure the epithermal neutron fluxes of ABNSs in a high accuracy.

  1. An accelerator-based epithermal photoneutron source for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Nigg, D.W.; Mitchell, H.E.; Harker, Y.D.; Yoon, W.Y. [and others

    1995-11-01

    Therapeutically-useful epithermal-neutron beams for BNCT are currently generated by nuclear reactors. Various accelerator-based neutron sources for BNCT have been proposed and some low intensity prototypes of such sources, generally featuring the use of proton beams and beryllium or lithium targets have been constructed. This paper describes an alternate approach to the realization of a clinically useful accelerator-based source of epithermal neutrons for BNCT that reconciles the often conflicting objectives of target cooling, neutron beam intensity, and neutron beam spectral purity via a two stage photoneutron production process.

  2. Search for active-sterile neutrino mixing using neutral-current interactions in NOvA

    OpenAIRE

    Adamson, P.; Aliaga, L.; Ambrose, D.; Anfimov, N.; Antoshkin, A.; Arrieta-Diaz, E.; Augsten, K.; Aurisano, A.; Backhouse, C.; Baird, M.; Bambah, B. A.; Bays, K.; Behera, B.; Bending, S.; Bernstein, R.

    2017-01-01

    We report results from the first search for sterile neutrinos mixing with active neutrinos through a reduction in the rate of neutral-current interactions over a baseline of 810 km between the NOvA detectors. Analyzing a 14-kton detector equivalent exposure of 6.05 × 1020 protons-on-target in the NuMI beam at Fermilab, we observe 95 neutral-current candidates at the Far Detector compared with 83.5 � 9.7ðstatÞ � 9.4ðsystÞ events predicted assuming mixing only occurs between active ...

  3. Measurement of epithermal neutrons by a coherent demodulation technique

    CERN Document Server

    Horiuchi, N; Takahashi, H; Kobayashi, H; Harasawa, S

    2000-01-01

    Epithermal neutrons have been measured using a neutron dosimeter via a coherent demodulation technique. This dosimeter consists of CsI(Tl)-photodiode scintillation detectors, four of which are coupled to neutron-gamma converting foils of various sizes. Neutron-gamma converting foils of In, Au and Co materials were used, each of which has a large capture cross section which peaks in the epithermal neutron energy region. The type of foil was selected according to the material properties that best correspond to the energy of the epithermal neutrons to be measured. In addition, the proposed technique was applied using Au-foils in order to measure the Cd ratio. The validity of the proposed technique was examined using an sup 2 sup 4 sup 1 Am-Be source placed in a testing stack of polyethylene blocks, and the results were compared with the theoretical values calculated by the Monte Carlo calculation. Finally, the dosimeter was applied for measuring epithermal neutrons and the Cd ratio in an experimental beam-tube o...

  4. Five-Level Active-Neutral-Point-Clamped DC/DC Converter

    DEFF Research Database (Denmark)

    Liu, Dong; Deng, Fujin; Chen, Zhe

    2016-01-01

    Multi-level converters are getting more and more attentions because of their obvious merits such as lower voltage stress and harmonic, smaller size of output filters, and so on. In this paper, a five-level active-neutral-point-clamped (5L-ANPC) dc/dc converter is proposed for power transfer...

  5. Optimization of source-sample-detector geometries for bulk hydrogen analysis using epithermal neutrons.

    Science.gov (United States)

    Csikai, J; Dóczi, R

    2009-01-01

    The advantages and limitations of epithermal neutrons in qualification of hydrocarbons via their H contents and C/H atomic ratios have been investigated systematically. Sensitivity of this method and the dimensions of the interrogated regions were determined for various types of hydrogenous samples. Results clearly demonstrate the advantages of direct neutron detection, e.g. by BF(3) counters as compared to the foil activation method in addition to using the hardness of the spectral shape of Pu-Be neutrons to that from a (252)Cf source.

  6. Neutralization of Bactericidal Activity Related to Antimicrobial Carryover in Broiler Carcass Rinse Samples.

    Science.gov (United States)

    Gamble, Gary R; Berrang, Mark E; Buhr, R Jeff; Hinton, Arthur; Bourassa, Dianna V; Ingram, Kimberly D; Adams, Eric S; Feldner, Peggy W; Johnston, John J

    2017-04-01

    Studies were conducted to examine the ability of three chemicals to neutralize residual antibacterial activity of commercial antimicrobial chemicals used in poultry processing. Chemical antimicrobial interventions used in poultry processing may have potential for carryover into whole poultry carcass buffered peptone water (BPW) rinses collected for monitoring Salmonella contamination. Such carryover may lead to false-negative results due to continuing bactericidal action of the antimicrobial chemicals in the rinse. To simulate testing procedures used to detect Salmonella contamination, studies were conducted by separately adding test neutralizers (highly refined soy lecithin, sodium thiosulfate, or sodium bicarbonate) to BPW and using these solutions as carcass rinses. Control samples consisted of BPW containing no additional neutralizing agents. One of four antimicrobial solutions (cetylpyridinium chloride, peroxyacetic acid, acidified sodium chlorite, and a pH 1 hydrochloric:citric acid mix) was then added to the rinses. The four antimicrobial solutions were prepared at maximum allowable concentrations and diluted with modified BPW rinses to volumes simulating maximum carryover. These solutions were then inoculated with a mixed culture of five nalidixic acid-resistant Salmonella serovars at 10(6) CFU/mL. The inoculated rinse was stored at 4°C for 24 h, and Salmonella was enumerated by direct plating on brilliant green sulfa agar supplemented with nalidixic acid. Results indicate that incorporation of optimal concentrations of three neutralizing agents into BPW neutralized the demonstrated carryover effects of each of the four antimicrobial solutions tested, allowing recovery of viable Salmonella at 10(6) CFU/mL (P > 0.05), equivalent to recovery from carcass rinses with no antimicrobial carryover. Incorporation of these neutralizers in BPW for Salmonella monitoring may reduce false-negative results and aid regulatory agencies in accurate reporting of Salmonella

  7. Myotoxic activity of phospholipases A2 isolated from cobra venoms: neutralization by polyvalent antivenoms.

    Science.gov (United States)

    Mebs, D

    1986-01-01

    Phospholipases A2 which produce myonecrosis when injected i.m. into mice were isolated from venoms of Naja nigricollis, N.h.haje and N.nivea by gel filtration, ion-exchange chromatography on SP-Sephadex C-25 and CM-cellulose and by hydrophobic interaction chromatography on Phenyl-Sepharose CL-4B. Basic polypeptides of the cardio/cytotoxin-type were essentially free of myotoxic activity. Polyvalent antivenoms were tested for their ability to neutralize the myotoxic activity of the phospholipases A2 when mixed with them prior to injection. Antivenoms from Behringwerke (Orient, Central Africa, North Africa) and from the South African Institute for Medical Research, but not habu (Trimeresurus flavoviridis) monovalent antivenom, neutralized the myotoxic activity of the phospholipases A2.

  8. Reporter gene assay for the quantification of the activity and neutralizing antibody response to TNFα antagonists

    DEFF Research Database (Denmark)

    Lallemand, Christophe; Kavrochorianou, Nadia; Steenholdt, Casper

    2011-01-01

    A cell-based assay has been developed for the quantification of the activity of TNFα antagonists based on human erythroleukemic K562 cells transfected with a NFκB regulated firefly luciferase reporter-gene construct. Both drug activity and anti-drug neutralizing antibodies can be quantified...... with a high degree of precision within 2h, and without interference from cytokines and other factors known to activate NFκB. The assay cells also contain the Renilla luciferase reporter gene under the control of a constitutive promoter that allows TNFα-induced firefly luciferase activity to be normalized...

  9. Active to sterile neutrino mixing limits from neutral-current interactions in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; /Fermilab; Auty, D.J.; /Sussex U.; Ayres, D.S.; /Argonne; Backhouse, C.; /Oxford U.; Barr, G.; /Oxford U.; Bishai, M.; /Brookhaven; Blake, A.; /Cambridge U.; Bock, G.J.; /Fermilab; Boehnlein, D.J.; /Fermilab; Bogert, D.; /Fermilab; Cavanaugh, S.; /Harvard U., Phys. Dept. /Tufts U.

    2011-04-01

    Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07 x 10{sup 20} protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 {+-} 28(stat.) {+-} 37(syst.) for oscillations among three active flavors. The fraction f{sub s} of disappearing {nu}{sub {mu}} that may transition to {nu}{sub s} is found to be less than 22% at the 90% C.L.

  10. The Chahnaly low sulfidation epithermal gold deposit, western Makran volcanic arc, southeastern Iran

    Science.gov (United States)

    Sholeh, Ali; Rastad, Ebrahim; Huston, David L.; Gemmell, J. Bruce; Taylor, Ryan D.

    2016-01-01

    The Chahnaly low-sulfidation epithermal Au deposit and nearby Au prospects are located northwest of the intermittently active Bazman stratovolcano on the western end of the Makran volcanic arc, which formed as the result of subduction of the remnant Neo-Tethyan oceanic crust beneath the Lut block. The arc hosts the Siah Jangal epithermal and Kharestan porphyry prospects, near Taftan volcano, as well as the Saindak Cu-Au porphyry deposit and world-class Reko Diq Cu-Au porphyry deposit, near Koh-i-Sultan volcano to the east-northeast in Pakistan. The host rocks for the Chahnaly deposit include early Miocene andesite and andesitic volcaniclastic rocks that are intruded by younger dacitic domes. Unaltered late Miocene dacitic ignimbrites overlie these rocks. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb zircon geochronology data yield ages between 21.8 and 9.9 Ma for the acidic-intermediate regional volcanism. The most recent volcanic activity of the Bazman stratovolcano involved extrusion of an olivine basalt during Pliocene to Quaternary times. Interpretation of geochemical data indicate that the volcanic rocks are synsubduction and calc-alkaline to subalkaline. The lack of a significant negative Eu anomaly, a listric-shaped rare earth element pattern, and moderate La/Yb ratios of host suites indicate a high water content of the source magma.

  11. Serum neutralizing activities from a Beijing homosexual male cohort infected with different subtypes of HIV-1 in China.

    Directory of Open Access Journals (Sweden)

    Mingshun Zhang

    Full Text Available Protective antibodies play a critical role in an effective HIV vaccine; however, eliciting antibodies to block infection by viruses from diverse genetic subtypes remains a major challenge. As the world's most populous country, China has been under the threat of at least three major subtypes of circulating HIV-1 viruses. Understanding the cross reactivity and specificities of serum antibody responses that mediate broad neutralization of the virus in HIV-1 infected Chinese patients will provide valuable information for the design of vaccines to prevent HIV-1 transmission in China. Sera from a cohort of homosexual men, who have been managed by a major HIV clinical center in Beijing, China, were analyzed for cross-sectional neutralizing activities against pseudotyped viruses expressing Env antigens of the major subtype viruses (AE, BC and B subtypes circulating in China. Neutralizing activities in infected patients' blood were most capable of neutralizing viruses in the homologous subtype; however, a subset of blood samples was able to achieve broad neutralizing activities across different subtypes. Such cross neutralizing activity took 1-2 years to develop and CD4 binding site antibodies were critical components in these blood samples. Our study confirmed the presence of broadly neutralizing sera in China's HIV-1 patient population. Understanding the specificity and breadth of these neutralizing activities can guide efforts for the development of HIV vaccines against major HIV-1 viruses in China.

  12. Mechanical Activation-Assisted Reductive Leaching of Cadmium from Zinc Neutral Leaching Residue Using Sulfur Dioxide

    Science.gov (United States)

    Zhang, Chun; Min, Xiaobo; Chai, Liyuan; Zhang, Jianqiang; Wang, Mi

    2015-12-01

    In this work, zinc neutral leaching residue was mechanically activated by ball-milling. The subsequent leaching behavior and kinetics of cadmium extraction in a mixed SO2-H2SO4 system were studied. Changes in the crystalline phase, lattice distortion, particle size and morphology, which were induced by mechanical activation, were also investigated. The activated samples showed different physicochemical characteristics, and cadmium extraction was found to be easier than for the un-activated samples. Under the same conditions, mechanical activation contributed to higher cadmium leaching. The cadmium extraction kinetics at 75-95°C was found to fit the shrinking core model. The raw neutral leaching residue, and the samples activated for 60 min and 120 min had a calculated activation energy of 65.02 kJ/mol, 59.45 kJ/mol and 53.46 kJ/mol, respectively. The leaching residue was characterized by ICP, XRD and SEM analysis. According to XRD analysis, the main phases in the residue were lead sulfate (PbSO4), zinc sulfide (ZnS) and cadmium sulfide (CdS).

  13. The optimal windows for seismically-enhanced gold precipitation in the epithermal environment

    OpenAIRE

    Sanchez-Alfaro, Pablo; Reich, Martin; Driesner, Thomas; Cembrano, José; Arancibia,Gloria; Pérez-Flores, Pamela; Heinrich, Christoph A.; Rowland, Julie; Tardani, Daniele; Lange, Dietrich; Campos,Eduardo

    2016-01-01

    Highlights • A geothermal system was studied as a modern analogue of epithermal Au deposits • Fluid data were combined with thermodynamic modeling and numerical simulations • Small-magnitude (Mw < 2) earthquakes can produce large drops in Au solubility • Earthquake-driven flash vaporization is more efficient than cooling and boiling • Protracted seismicity enhances Au precipitation rates in the epithermal environment Abstract Epithermal gold (Au) deposit...

  14. Highly selective palladium–benzothiazole carbene-catalyzed allylation of active methylene compounds under neutral conditions

    Directory of Open Access Journals (Sweden)

    Antonio Monopoli

    2015-06-01

    Full Text Available The Pd–benzothiazol-2-ylidene complex I was found to be a chemoselective catalyst for the Tsuji–Trost allylation of active methylene compounds carried out under neutral conditions and using carbonates as allylating agents. The proposed protocol consists in a simplified procedure adopting an in situ prepared catalyst from Pd2dba3 and 3-methylbenzothiazolium salt V as precursors. A comparison of the performance of benzothiazole carbene with phosphanes and an analogous imidazolium carbene ligand is also proposed.

  15. 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

    2001-01-01

    We have characterized the neutralization of the inhibitory activity of the serpin plasminogen activator inhibitor-1 (PAI-1) by a number of structurally distinct organochemicals, including compounds with environment-sensitive spectroscopic properties. In contrast to latent and reactive center...... by 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......-cleaved PAI-1 and PAI-1 in complex with urokinase-type plasminogen activator (uPA), active PAI-1 strongly increased the fluorescence of the PAI-1-neutralizing compounds 1-anilinonaphthalene-8-sulfonic acid and 4,4'-dianilino-1,1'-bisnaphthyl-5,5'-disulfonic acid. The fluorescence increase could be competed...

  16. Geochemical characteristics of igneous rocks associated with epithermal mineral deposits—A review

    Science.gov (United States)

    du Bray, Edward A.

    2017-01-01

    Newly synthesized data indicate that the geochemistry of igneous rocks associated with epithermal mineral deposits varies extensively and continuously from subalkaline basaltic to rhyolitic compositions. Trace element and isotopic data for these rocks are consistent with subduction-related magmatism and suggest that the primary source magmas were generated by partial melting of the mantle-wedge above subducting oceanic slabs. Broad geochemical and petrographic diversity of individual igneous rock units associated with epithermal deposits indicate that the associated magmas evolved by open-system processes. Following migration to shallow crustal reservoirs, these magmas evolved by assimilation, recharge, and partial homogenization; these processes contribute to arc magmatism worldwide.Although epithermal deposits with the largest Au and Ag production are associated with felsic to intermediate composition igneous rocks, demonstrable relationships between magmas having any particular composition and epithermal deposit genesis are completely absent because the composition of igneous rock units associated with epithermal deposits ranges from basalt to rhyolite. Consequently, igneous rock compositions do not constitute effective exploration criteria with respect to identification of terranes prospective for epithermal deposit formation. However, the close spatial and temporal association of igneous rocks and epithermal deposits does suggest a mutual genetic relationship. Igneous systems likely contribute heat and some of the fluids and metals involved in epithermal deposit formation. Accordingly, deposit formation requires optimization of source metal contents, appropriate fluid compositions and characteristics, structural features conducive to hydrothermal fluid flow and confinement, and receptive host rocks, but not magmas with special compositional characteristics.

  17. Production in yeast of pseudotype virus-like particles harboring functionally active antibody fragments neutralizing the cytolytic activity of vaginolysin

    Directory of Open Access Journals (Sweden)

    Pleckaityte Milda

    2011-12-01

    Full Text Available Abstract Background Recombinant antibodies can be produced in different formats and different expression systems. Single chain variable fragments (scFvs represent an attractive alternative to full-length antibodies and they can be easily produced in bacteria or yeast. However, the scFvs exhibit monovalent antigen-binding properties and short serum half-lives. The stability and avidity of the scFvs can be improved by their multimerization or fusion with IgG Fc domain. The aim of the current study was to investigate the possibilities to produce in yeast high-affinity scFv-Fc proteins neutralizing the cytolytic activity of vaginolysin (VLY, the main virulence factor of Gardnerella vaginalis. Results The scFv protein derived from hybridoma cell line producing high-affinity neutralizing antibodies against VLY was fused with human IgG1 Fc domain. Four different variants of anti-VLY scFv-Fc fusion proteins were constructed and produced in yeast Saccharomyces cerevisiae. The non-tagged scFv-Fc and hexahistidine-tagged scFv-Fc proteins were found predominantly as insoluble aggregates and therefore were not suitable for further purification and activity testing. The addition of yeast α-factor signal sequence did not support secretion of anti-VLY scFv-Fc but increased the amount of its intracellular soluble form. However, the purified protein showed a weak VLY-neutralizing capability. In contrast, the fusion of anti-VLY scFv-Fc molecules with hamster polyomavirus-derived VP2 protein and its co-expression with VP1 protein resulted in an effective production of pseudotype virus-like particles (VLPs that exhibited strong VLY-binding activity. Recombinant scFv-Fc molecules displayed on the surface of VLPs neutralized VLY-mediated lysis of human erythrocytes and HeLa cells with high potency comparable to that of full-length antibody. Conclusions Recombinant scFv-Fc proteins were expressed in yeast with low efficiency. New approach to display the sc

  18. Search for active-sterile neutrino mixing using neutral-current interactions in NOvA

    Science.gov (United States)

    Adamson, P.; Aliaga, L.; Ambrose, D.; Anfimov, N.; Antoshkin, A.; Arrieta-Diaz, E.; Augsten, K.; Aurisano, A.; Backhouse, C.; Baird, M.; Bambah, B. A.; Bays, K.; Behera, B.; Bending, S.; Bernstein, R.; Bhatnagar, V.; Bhuyan, B.; Bian, J.; Blackburn, T.; Bolshakova, A.; Bromberg, C.; Brown, J.; Brunetti, G.; Buchanan, N.; Butkevich, A.; Bychkov, V.; Campbell, M.; Catano-Mur, E.; Childress, S.; Choudhary, B. C.; Chowdhury, B.; Coan, T. E.; Coelho, J. A. B.; Colo, M.; Cooper, J.; Corwin, L.; Cremonesi, L.; Cronin-Hennessy, D.; Davies, G. S.; Davies, J. P.; Derwent, P. F.; Dharmapalan, R.; Ding, P.; Djurcic, Z.; Dukes, E. C.; Duyang, H.; Edayath, S.; Ehrlich, R.; Feldman, G. J.; Frank, M. J.; Gabrielyan, M.; Gallagher, H. R.; Germani, S.; Ghosh, T.; Giri, A.; Gomes, R. A.; Goodman, M. C.; Grichine, V.; Groh, M.; Group, R.; Grover, D.; Guo, B.; Habig, A.; Hartnell, J.; Hatcher, R.; Hatzikoutelis, A.; Heller, K.; Himmel, A.; Holin, A.; Howard, B.; Hylen, J.; Jediny, F.; Judah, M.; Kafka, G. K.; Kalra, D.; Kasahara, S. M. S.; Kasetti, S.; Keloth, R.; Kolupaeva, L.; Kotelnikov, S.; Kourbanis, I.; Kreymer, A.; Kumar, A.; Kurbanov, S.; Lackey, T.; Lang, K.; Lee, W. M.; Lin, S.; Lokajicek, M.; Lozier, J.; Luchuk, S.; Maan, K.; Magill, S.; Mann, W. A.; Marshak, M. L.; Matera, K.; Matveev, V.; Méndez, D. P.; Messier, M. D.; Meyer, H.; Miao, T.; Miller, W. H.; Mishra, S. R.; Mohanta, R.; Moren, A.; Mualem, L.; Muether, M.; Mufson, S.; Murphy, R.; Musser, J.; Nelson, J. K.; Nichol, R.; Niner, E.; Norman, A.; Nosek, T.; Oksuzian, Y.; Olshevskiy, A.; Olson, T.; Paley, J.; Patterson, R. B.; Pawloski, G.; Pershey, D.; Petrova, O.; Petti, R.; Phan-Budd, S.; Plunkett, R. K.; Poling, R.; Potukuchi, B.; Principato, C.; Psihas, F.; Radovic, A.; Rameika, R. A.; Rebel, B.; Reed, B.; Rocco, D.; Rojas, P.; Ryabov, V.; Sachdev, K.; Sail, P.; Samoylov, O.; Sanchez, M. C.; Schroeter, R.; Sepulveda-Quiroz, J.; Shanahan, P.; Sheshukov, A.; Singh, J.; Singh, J.; Singh, P.; Singh, V.; Smolik, J.; Solomey, N.; Song, E.; Sousa, A.; Soustruznik, K.; Strait, M.; Suter, L.; Talaga, R. L.; Tas, P.; Thayyullathil, R. B.; Thomas, J.; Tian, X.; Tognini, S. C.; Tripathi, J.; Tsaris, A.; Urheim, J.; Vahle, P.; Vasel, J.; Vinton, L.; Vold, A.; Vrba, T.; Wang, B.; Wetstein, M.; Whittington, D.; Wojcicki, S. G.; Wolcott, J.; Yadav, N.; Yang, S.; Zalesak, J.; Zamorano, B.; Zwaska, R.; NOvA Collaboration

    2017-10-01

    We report results from the first search for sterile neutrinos mixing with active neutrinos through a reduction in the rate of neutral-current interactions over a baseline of 810 km between the NOvA detectors. Analyzing a 14-kton detector equivalent exposure of 6.05 ×1020 protons-on-target in the NuMI beam at Fermilab, we observe 95 neutral-current candidates at the Far Detector compared with 83.5 ±9.7 (stat ) ±9.4 (syst ) events predicted assuming mixing only occurs between active neutrino species. No evidence for νμ→νs transitions is found. Interpreting these results within a 3 +1 model, we place constraints on the mixing angles θ24<20.8 ° and θ34<31.2 ° at the 90% C.L. for 0.05 eV2≤Δ m412≤0.5 eV2 , the range of mass splittings that produce no significant oscillations over the Near Detector baseline.

  19. Correlated Observations of Epithermal Neutrons and Polar Illumination for Orbital Neutron Detectors

    Science.gov (United States)

    McClanahan, T. P.; Mitrofanov, I. G.; Boynton, W. V.; Chin, G.; Droege, G.; Evans, L. G.; Garvin, J.; Harshman, K.; Malakhov, A.; Livengood, T.; hide

    2012-01-01

    We correlate Lunar Reconnaisance Orbiter's (LRO) Lunar Exploration Neutron Detector (LEND) and the Lunar Prospector Neutron Spectrometer's (LPNS) orbital epithermal neutron maps of the Lunar high-latitudes with co-registered illumination maps derived from the Lunar Orbiter Laser Altimeter (LOLA) topography. Epithermal neutron count rate maps were derived from the LEND: 1) Collimated Sensor for Epithermal Neutrons, CSETNI-4 2) Uncollimated Sensor for Epithermal Neutrons, SETN and the Uncollimated Lunar Prospector: 3) Low-altitude and 4) High-altitude mapping phases. In this abstract we illustrate 1) and 3) and include 2) and 4) in our presentation. The correlative study provides unique perspectives on the regional epithermal neutron fluences from the Lunar polar regions under different detector and altitude configurations.

  20. Changing the electron donor improves azoreductase dye degrading activity at neutral pH.

    Science.gov (United States)

    Qi, Jingxian; Paul, Caroline E; Hollmann, Frank; Tischler, Dirk

    2017-05-01

    The oxygen-insensitive azoreductase AzoRo originating from Rhodococcus opacus 1CP was found to be most active at low pH (ca. 4) and high temperature (ca. 50°C). AzoRo is not an efficient biocatalyst when used at low pH due to stability problems. To overcome this issue, we discovered that AzoRo accepts an alternative electron donor, 1-benzyl-1,4-dihydronicotinamide (BNAH), which allows fast turnover at neutral pH. In order to screen this nicotinamide coenzyme mimic as a source of electrons, AzoRo-catalysed reactions were run under neutral conditions, under which typically slow rates are observed with NADH. For the reduction of 1 azo bond by azoreductases 2mol nicotinamide coenzyme are needed. AzoRo displayed Methyl Red (MR) reduction activities with NADH and NADPH of 5.49±0.14Umg-1 and 4.96±0.25Umg-1, respectively, whereas with BNAH it displayed 17.01±0.74Umg-1 (following BNAH oxidation) and 7.16±0.06Umg-1 (following MR reduction). Binding of BNAH to AzoRo was determined with a Km of 18.75±2.45μM (BNAH oxidation) and 12.45±0.47μM (MR reduction). In order to show applicability of this system an upscaled reaction was performed using 78.6μg of purified AzoRo to convert 2.96μmol of MR (total reaction volume: 40ml) within a 1h reaction. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Point mutations in the paramyxovirus F protein that enhance fusion activity shift the mechanism of complement-mediated virus neutralization.

    Science.gov (United States)

    Johnson, John B; Schmitt, Anthony P; Parks, Griffith D

    2013-08-01

    Parainfluenza virus 5 (PIV5) activates and is neutralized by the alternative pathway (AP) in normal human serum (NHS) but not by heat-inactivated (HI) serum. We have tested the relationship between the fusion activity within the PIV5 F protein, the activation of complement pathways, and subsequent complement-mediated virus neutralization. Recombinant PIV5 viruses with enhanced fusion activity were generated by introducing point mutations in the F fusogenic peptide (G3A) or at a distal site near the F transmembrane domain (S443P). In contrast to wild-type (WT) PIV5, the mutant G3A and S443P viruses were neutralized by both NHS and HI serum. Unlike WT PIV5, hyperfusogenic G3A and S443P viruses were potent C4 activators, C4 was deposited on NHS-treated mutant virions, and the mutants were neutralized by factor B-depleted serum but not by C4-depleted serum. Antibodies purified from HI human serum were sufficient to neutralize both G3A and S443P viruses in vitro but were ineffective against WT PIV5. Electron microscopy data showed greater deposition of purified human antibodies on G3A and S443P virions than on WT PIV5 particles. These data indicate that single amino acid changes that enhance the fusion activity of the PIV5 F protein shift the mechanism of complement activation in the context of viral particles or on the surface of virus-infected cells, due to enhanced binding of antibodies. We present general models for the relationship between enhanced fusion activity in the paramyxovirus F protein and increased susceptibility to antibody-mediated neutralization.

  2. Seminal quality and neutral alpha-glucosidase activity after sequential electroejaculation of chinchilla (Ch. lanigera).

    Science.gov (United States)

    Ponzio, M F; Roussy-Otero, G N; Ruiz, R D; Fiol de Cuneo, M

    2011-07-01

    The objectives of this study of seminal quality of chinchilla (Chinchilla lanigera) males were to evaluate (1) the use of neutral alpha-glucosidase (NAG) as a functional epididymal marker in this species, and (2) the effects of repetitive electroejaculation on sperm function and seminal NAG concentration. Semen was obtained by electroejaculation from sexually mature domestic Ch. lanigera males (n=6) once a week for six consecutive weeks, and evaluated to assess seminal volume and NAG activity, and sperm concentration and functional activity (motility, viability, membrane and acrosome integrity). Body weight was determined in all animals before each electroejaculation procedure. NAG activity was detected in all semen samples obtained, reaching a concentration of 55.4±6.8μU/mL. No significant variations were observed throughout the experimental period in any of the semen quality parameters evaluated. A reduction (P=0.001) in body weight was detected from the third week of experimentation and by the end of the experiments the animals lost a 7.2±0.9% of body weight. Overall, results in the present study confirm that NAG activity is detectable in chinchilla seminal plasma and that repetitive electroejaculation is not deleterious, on a short-term basis, to the semen characteristics. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Broadly Neutralizing Activity of Zika Virus-Immune Sera Identifies a Single Viral Serotype

    Directory of Open Access Journals (Sweden)

    Kimberly A. Dowd

    2016-08-01

    Full Text Available Recent epidemics of Zika virus (ZIKV have been associated with congenital malformation during pregnancy and Guillain-Barré syndrome. There are two ZIKV lineages (African and Asian that share >95% amino acid identity. Little is known regarding the ability of neutralizing antibodies elicited against one lineage to protect against the other. We investigated the breadth of the neutralizing antibody response following ZIKV infection by measuring the sensitivity of six ZIKV strains to neutralization by ZIKV-confirmed convalescent human serum or plasma samples. Contemporary Asian and early African ZIKV strains were similarly sensitive to neutralization regardless of the cellular source of virus. Furthermore, mouse immune serum generated after infection with African or Asian ZIKV strains was capable of neutralizing homologous and heterologous ZIKV strains equivalently. Because our study only defines a single ZIKV serotype, vaccine candidates eliciting robust neutralizing antibody responses should inhibit infection of both ZIKV lineages, including strains circulating in the Americas.

  4. The first identified cathelicidin from tree frogs possesses anti-inflammatory and partial LPS neutralization activities.

    Science.gov (United States)

    Mu, Lixian; Zhou, Lei; Yang, Juanjuan; Zhuang, Li; Tang, Jing; Liu, Tong; Wu, Jing; Yang, Hailong

    2017-06-07

    As of February 2017, approximately 7639 amphibian species have been described in the AmphibiaWeb database. However, only 20 cathelicidin-like antimicrobial peptides have been identified to date from 10 amphibian species. Half of these peptides were identified from genome sequences and have not yet been functionally characterized. In this study, a novel cathelicidin-like peptide designated cathelicidin-PP was purified from the skin of tree frog Polypedates puerensis. Cathelicidin-PP is a 32 residue peptide of sequence ASENGKCNLLCLVKKKLRAVGNVIKTVVGKIA. Circular dichroism spectroscopy indicated that cathelicidin-PP mainly adopts a β-sheet structure in membrane-mimetic solutions. Cathelicidin-PP exhibits potent antimicrobial activity against bacteria and fungi, especially Gram-negative bacteria. Meanwhile, it shows low cytotoxicity toward mammalian cells. Scanning electron microscopy analysis indicated that cathelicidin-PP kills bacteria through the disruption of the bacterial cell membrane integrity. Furthermore, cathelicidin-PP exerts significant anti-inflammatory functions by inhibiting the lipopolysaccharide (LPS)-mediated generation of nitric oxide and pro-inflammatory cytokines, tumor necrosis factor-α, interleukin-1β, and interleukin-6. The MAPKs (ERK, JNK, and p38) and NF-κB signaling pathways are involved in the anti-inflammatory effect. Cathelicidin-PP caused partial neutralization of LPS in a dose-dependent manner. Quantitative PCR indicated that infection of tree frogs with bacteria causes increased expression of cathelicidin-PP in immune-related tissues. Taken together, cathelicidin-PP is the first identified cathelicidin-like peptide from tree frogs. Our findings demonstrate that in addition to direct bactericidal capacity, cathelicidin-PP also possesses immunomodulatory properties, including partial neutralization of LPS, and inhibiting the production of inflammatory cytokines.

  5. The Activity of the Neutral Sphingomyelinase Is Important in T Cell Recruitment and Directional Migration

    Directory of Open Access Journals (Sweden)

    Lena Collenburg

    2017-08-01

    Full Text Available Breakdown of sphingomyelin as catalyzed by the activity of sphingomyelinases profoundly affects biophysical properties of cellular membranes which is particularly important with regard to compartmentalization of surface receptors and their signaling relay. As it is activated both upon TCR ligation and co-stimulation in a spatiotemporally controlled manner, the neutral sphingomyelinase (NSM has proven to be important in T cell activation, where it appears to play a particularly important role in cytoskeletal reorganization and cell polarization. Because these are important parameters in directional T cell migration and motility in tissues, we analyzed the role of the NSM in these processes. Pharmacological inhibition of NSM interfered with early lymph node homing of T cells in vivo indicating that the enzyme impacts on endothelial adhesion, transendothelial migration, sensing of chemokine gradients or, at a cellular level, acquisition of a polarized phenotype. NSM inhibition reduced adhesion of T cells to TNF-α/IFN-γ activated, but not resting endothelial cells, most likely via inhibiting high-affinity LFA-1 clustering. NSM activity proved to be highly important in directional T cell motility in response to SDF1-α, indicating that their ability to sense and translate chemokine gradients might be NSM dependent. In fact, pharmacological or genetic NSM ablation interfered with T cell polarization both at an overall morphological level and redistribution of CXCR4 and pERM proteins on endothelial cells or fibronectin, as well as with F-actin polymerization in response to SDF1-α stimulation, indicating that efficient directional perception and signaling relay depend on NSM activity. Altogether, these data support a central role of the NSM in T cell recruitment and migration both under homeostatic and inflamed conditions by regulating polarized redistribution of receptors and their coupling to the cytoskeleton.

  6. Assessment method for epithermal gold deposits in Northeast Washington State using weights-of-evidence GIS modeling

    Science.gov (United States)

    Boleneus, D.E.; Raines, G.L.; Causey, J.D.; Bookstrom, A.A.; Frost, T.P.; Hyndman, P.C.

    2001-01-01

    The weights-of-evidence analysis, a quantitative mineral resource mapping tool, is used to delineate favorable areas for epithermal gold deposits and to predict future exploration activity of the mineral industry for similar deposits in a four-county area (222 x 277 km), including the Okanogan and Colville National Forests of northeastern Washington. Modeling is applied in six steps: (1) building a spatial digital database, (2) extracting predictive evidence for a particular deposit, based on an exploration model, (3) calculating relative weights for each predictive map, (4) combining the geologic evidence maps to predict the location of undiscovered mineral resources and (5) measuring the intensity of recent exploration activity by use of mining claims on federal lands, and (6) combining mineral resource and exploration activity into an assessment model of future mining activity. The analysis is accomplished on a personal computer using ArcView GIS platform with Spatial Analyst and Weights-of-Evidence software. In accord with the descriptive model for epithermal gold deposits, digital geologic evidential themes assembled include lithologic map units, thrust faults, normal faults, and igneous dikes. Similarly, geochemical evidential themes include placer gold deposits and gold and silver analyses from stream sediment (silt) samples from National Forest lands. Fifty mines, prospects, or occurrences of epithermal gold deposits, the training set, define the appropriate a really-associated terrane. The areal (or spatial) correlation of each evidential theme with the training set yield predictor theme maps for lithology, placer sites and normal faults. The weights-of-evidence analysis disqualified the thrust fault, dike, and gold and silver silt analyses evidential themes because they lacked spatial correlation with the training set. The decision to accept or reject evidential themes as predictors is assisted by considering probabilistic data consisting of weights and

  7. Evidence for a modulation of neutral trehalase activity by Ca2+ and cAMP signaling pathways in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Souza A.C.

    2002-01-01

    Full Text Available Saccharomyces cerevisiae neutral trehalase (encoded by NTH1 is regulated by cAMP-dependent protein kinase (PKA and by an endogenous modulator protein. A yeast strain with knockouts of CMK1 and CMK2 genes (cmk1cmk2 and its isogenic control (CMK1CMK2 were used to investigate the role of CaM kinase II in the in vitro activation of neutral trehalase during growth on glucose. In the exponential growth phase, cmk1cmk2 cells exhibited basal trehalase activity and an activation ratio by PKA very similar to that found in CMK1CMK2 cells. At diauxie, even though both cells presented comparable basal trehalase activities, cmk1cmk2 cells showed reduced activation by PKA and lower total trehalase activity when compared to CMK1CMK2 cells. To determine if CaM kinase II regulates NTH1 expression or is involved in post-translational modulation of neutral trehalase activity, NTH1 promoter activity was evaluated using an NTH1-lacZ reporter gene. Similar ß-galactosidase activities were found for CMK1CMK2 and cmk1cmk2 cells, ruling out the role of CaM kinase II in NTH1 expression. Thus, CaM kinase II should act in concert with PKA on the activation of the cryptic form of neutral trehalase. A model for trehalase regulation by CaM kinase II is proposed whereby the target protein for Ca2+/CaM-dependent kinase II phosphorylation is not the neutral trehalase itself. The possible identity of this target protein with the recently identified trehalase-associated protein YLR270Wp is discussed.

  8. Generation of recombinant single-chain antibodies neutralizing the cytolytic activity of vaginolysin, the main virulence factor of Gardnerella vaginalis.

    Science.gov (United States)

    Pleckaityte, Milda; Mistiniene, Edita; Lasickiene, Rita; Zvirblis, Gintautas; Zvirbliene, Aurelija

    2011-11-03

    Gardnerella vaginalis is identified as the predominant colonist of the vaginal tract in women with bacterial vaginosis. Vaginolysin (VLY) is a protein toxin released by G. vaginalis. VLY possesses cytolytic activity and is considered as a main virulence factor of G. vaginalis. Inhibition of VLY-mediated cell lysis by antibodies may have important physiological relevance. Single-chain variable fragments of immunoglobulins (scFvs) were cloned from two hybridoma cell lines producing neutralizing antibodies against VLY and expressed as active proteins in E. coli. For each hybridoma, two variants of anti-VLY scFv consisting of either VL-VH or VH-VL linked with a 20 aa-long linker sequence (G₄S)₄ were constructed. Recovery of scFvs from inclusion bodies with subsequent purification by metal-chelate chromatography resulted in VLY-binding proteins that were predominantly monomeric. The antigen-binding activity of purified scFvs was verified by an indirect ELISA. The neutralizing activity was investigated by in vitro hemolytic assay and cytolytic assay using HeLa cell line. Calculated apparent Kd values and neutralizing potency of scFvs were in agreement with those of parental full-length antibodies. VH-VL and VL-VH variants of scFvs showed similar affinity and neutralizing potency. The anti-VLY scFvs derived from hybridoma clone 9B4 exhibited high VLY-neutralizing activity both on human erythrocytes and cervical epithelial HeLa cells. Hybridoma-derived scFvs with VLY-binding activity were expressed in E. coli. Recombinant anti-VLY scFvs inhibited VLY-mediated cell lysis. The monovalent scFvs showed reduced affinity and neutralizing potency as compared to the respective full-length antibodies. The loss of avidity could be restored by generating scFv constructs with multivalent binding properties. Generated scFvs is the first example of recombinant single-chain antibodies with VLY-neutralizing activity produced in prokaryote expression system. G. vaginalis caused

  9. Generation of recombinant single-chain antibodies neutralizing the cytolytic activity of vaginolysin, the main virulence factor of Gardnerella vaginalis

    Directory of Open Access Journals (Sweden)

    Pleckaityte Milda

    2011-11-01

    Full Text Available Abstract Background Gardnerella vaginalis is identified as the predominant colonist of the vaginal tract in women with bacterial vaginosis. Vaginolysin (VLY is a protein toxin released by G. vaginalis. VLY possesses cytolytic activity and is considered as a main virulence factor of G. vaginalis. Inhibition of VLY-mediated cell lysis by antibodies may have important physiological relevance. Results Single-chain variable fragments of immunoglobulins (scFvs were cloned from two hybridoma cell lines producing neutralizing antibodies against VLY and expressed as active proteins in E. coli. For each hybridoma, two variants of anti-VLY scFv consisting of either VL-VH or VH-VL linked with a 20 aa-long linker sequence (G4S4 were constructed. Recovery of scFvs from inclusion bodies with subsequent purification by metal-chelate chromatography resulted in VLY-binding proteins that were predominantly monomeric. The antigen-binding activity of purified scFvs was verified by an indirect ELISA. The neutralizing activity was investigated by in vitro hemolytic assay and cytolytic assay using HeLa cell line. Calculated apparent Kd values and neutralizing potency of scFvs were in agreement with those of parental full-length antibodies. VH-VL and VL-VH variants of scFvs showed similar affinity and neutralizing potency. The anti-VLY scFvs derived from hybridoma clone 9B4 exhibited high VLY-neutralizing activity both on human erythrocytes and cervical epithelial HeLa cells. Conclusions Hybridoma-derived scFvs with VLY-binding activity were expressed in E. coli. Recombinant anti-VLY scFvs inhibited VLY-mediated cell lysis. The monovalent scFvs showed reduced affinity and neutralizing potency as compared to the respective full-length antibodies. The loss of avidity could be restored by generating scFv constructs with multivalent binding properties. Generated scFvs is the first example of recombinant single-chain antibodies with VLY-neutralizing activity produced in

  10. Compton suppression method and epithermal NAA in the determination of nutrients and heavy metals in Nigerian food and beverages

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Y.A., E-mail: yaahmed1@gmail.co [Reactor Engineering Section, Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria); Nuclear Engineering Teaching Laboratory, University of Texas at Austin, Austin, TX 78758 (United States); Landsberger, S.; O' Kelly, D.J.; Braisted, J. [Nuclear Engineering Teaching Laboratory, University of Texas at Austin, Austin, TX 78758 (United States); Gabdo, H. [Physics Department, Federal College of Education, Yola (Nigeria); Ewa, I.O.B.; Umar, I.M.; Funtua, I.I. [Reactor Engineering Section, Centre for Energy Research and Training, Ahmadu Bello University, Zaria (Nigeria)

    2010-10-15

    We used in this study Compton suppression method and epithermal neutron activation analysis to determine the concentration of nutrients and heavy metals in Nigerian food and beverages. The work was performed at the University of Texas TRIGA Reactor by short, medium, and long irradiation protocols, using thermal flux of 1.4x10{sup 12} n cm{sup -2} s{sup -1} and epithermal flux of 1.4x10{sup 11} n cm{sup -2} s{sup -1}. Application of Compton suppression method has reduced interferences from Compton scattered photons thereby allowing easy evaluation of Na, Cl, Ca, Cu, Mn, Mg, Co, Cr, Rb, Fe, and Se. The epithermal NAA method has enabled determination of Cd, As, Ba, Sr, Br, I, and V with little turn-around time. Quality Control and Quality Assurance of the method was tested by analyzing four Standard Reference Materials (non-fat powdered milk, apple leaves, citrus leaves, and peach leaves) obtained from National Institute for Standards and Technology. Our results show that sorghum, millet, and maize have high values of Zn, Mn, Fe, low values of Cd, As, and Se. Powdered milks, rice, beans, and soybeans were found to have moderate amounts of all the elements. Tobacco recorded high content of Cd, Mn, and As, whereas tea, tsobo leaves, Baobab leaves, and okro seed have more As values than others. However, biscuits, macaroni, spaghetti, and noodles show lower concentrations of all the elements. The distribution of these nutrients and heavy metals in these food and beverages shows the need to fortify biscuits and pastas with micro and macro-nutrients and reduce the use of tobacco, tea, tsobo leaves, Baobab leaves, and Okro seed to avoid intake of heavy elements.

  11. Compton suppression method and epithermal NAA in the determination of nutrients and heavy metals in Nigerian food and beverages.

    Science.gov (United States)

    Ahmed, Y A; Landsberger, S; O'Kelly, D J; Braisted, J; Gabdo, H; Ewa, I O B; Umar, I M; Funtua, I I

    2010-10-01

    We used in this study Compton suppression method and epithermal neutron activation analysis to determine the concentration of nutrients and heavy metals in Nigerian food and beverages. The work was performed at the University of Texas TRIGA Reactor by short, medium, and long irradiation protocols, using thermal flux of 1.4x10(12)n cm(-2)s(-1) and epithermal flux of 1.4x10(11)n cm(-2)s(-1). Application of Compton suppression method has reduced interferences from Compton scattered photons thereby allowing easy evaluation of Na, Cl, Ca, Cu, Mn, Mg, Co, Cr, Rb, Fe, and Se. The epithermal NAA method has enabled determination of Cd, As, Ba, Sr, Br, I, and V with little turn-around time. Quality Control and Quality Assurance of the method was tested by analyzing four Standard Reference Materials (non-fat powdered milk, apple leaves, citrus leaves, and peach leaves) obtained from National Institute for Standards and Technology. Our results show that sorghum, millet, and maize have high values of Zn, Mn, Fe, low values of Cd, As, and Se. Powdered milks, rice, beans, and soybeans were found to have moderate amounts of all the elements. Tobacco recorded high content of Cd, Mn, and As, whereas tea, tsobo leaves, Baobab leaves, and okro seed have more As values than others. However, biscuits, macaroni, spaghetti, and noodles show lower concentrations of all the elements. The distribution of these nutrients and heavy metals in these food and beverages shows the need to fortify biscuits and pastas with micro and macro-nutrients and reduce the use of tobacco, tea, tsobo leaves, Baobab leaves, and Okro seed to avoid intake of heavy elements. Copyright 2010 Elsevier Ltd. All rights reserved.

  12. Performance of thermally activated dolomite for the treatment of Ni and Zn in contaminated neutral drainage.

    Science.gov (United States)

    Calugaru, Iuliana Laura; Neculita, Carmen Mihaela; Genty, Thomas; Bussière, Bruno; Potvin, Robin

    2016-06-05

    Intensive research is ongoing for developing low-cost and highly efficient materials in metal removal from contaminated effluents. The present study evaluated dolomite [CaMg(CO3)2], both raw and modified by thermal activation (charring), for Ni and Zn treatment in contaminated neutral drainage (CND). Batch adsorption testing (equilibrium and kinetics) were conducted at pH 6, to evaluate the performance of initial vs. modified dolomite, and to assess potential mechanisms of metal removal. Charring of dolomite led to a rigid and porous material, mainly consisting of CaCO3 and MgO, which showed a sorption capacity increased sevenfold for Zn and doubled for Ni, relative to the raw material. In addition, Freundlich model best described the sorption of the both metals by dolomite, whereas the Langmuir model best described their sorption on charred dolomite. Plausible mechanisms of metal removal include cation exchange, surface precipitation and sorption processes, with carbonate ions and magnesium oxides acting as active centers. Based on these results, charred dolomite seems a promising option for the efficient treatment of Ni and Zn in CND. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Relationship between the loss of neutralizing antibody binding and fusion activity of the F protein of human respiratory syncytial virus

    Directory of Open Access Journals (Sweden)

    Sarisky Robert T

    2007-07-01

    Full Text Available Abstract To elucidate the relationship between resistance to HRSV neutralizing antibodies directed against the F protein and the fusion activity of the F protein, a recombinant approach was used to generate a panel of mutations in the major antigenic sites of the F protein. These mutant proteins were assayed for neutralizing mAb binding (ch101F, palivizumab, and MAb19, level of expression, post-translational processing, cell surface expression, and fusion activity. Functional analysis of the fusion activity of the panel of mutations revealed that the fusion activity of the F protein is tolerant to multiple changes in the site II and IV/V/VI region in contrast with the somewhat limited spectrum of changes in the F protein identified from the isolation of HRSV neutralizing antibody virus escape mutants. This finding suggests that aspects other than fusion activity may limit the spectrum of changes tolerated within the F protein that are selected for by neutralizing antibodies.

  14. Geochemical patterns of epithermal ore formation in the Okhotsk-Chukotka volcanoplutonic belt (Northeast Russia)

    Science.gov (United States)

    Volkov, A. V.; Murashov, K. Yu.; Sidorov, A. A.

    2017-05-01

    Ores of epithermal Au-Ag deposits of the Okhotsk-Chukotka volcanoplutonic belt are characterized by enrichment in a wide spectrum of elements in relation to the average upper crustal values. The data obtained show that the host volcanic rocks are the most likely sources of minor elements and REEs for the fluids that formed epithermal Au-Ag deposits of the Okhotsk-Chukotka volcanoplutonic belt.

  15. Dose measurements and calculations in the epithermal neutron beam at the Brookhaven Medical Research Reactor (BMRR)

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, R.G.; Greenberg, D.; Kamen, Y.; Fiarman, S. (Brookhaven National Lab., Upton, NY (USA). Medical Dept.); Benary, V. (Brookhaven National Lab., Upton, NY (USA). Medical Dept. Tel Aviv Univ. (Israel)); Kalef-Ezra, J. (Brookhaven National Lab., Upton, NY (USA). Medical Dept. Ioannina Univ. (Greece)); Wielopolski, L. (Brookhaven National Lab., Upton, NY (USA). Medical Dept. State Univ. of New

    1990-01-01

    The characteristics of the epithermal neutron beam at BMRR were measured, calculated, and reported. This beam has already been used for animal irradiations. We anticipate that it will be used for clinical trials. Thermal and epithermal neutron flux densities distributions, and dose rate distributions, as a function of depth were measured in a lucite dog-head phantom. Monte Carlo calculations were performed and compared with the measured values. 2 refs., 4 figs., 1 tab.

  16. Comparison of ACE inhibitory activity in skimmed goat and cow milk hydrolyzed by alcalase, flavourzyme, neutral protease and proteinase K

    Directory of Open Access Journals (Sweden)

    Bao Chunju

    2016-06-01

    Full Text Available Angiotensin I converting enzyme (ACE inhibitory peptides derived from milk proteins have obvious effect of lowering blood pressure, safe and non-toxic side effects. This study compared four commercial proteases, namely alcalase, flavourzyme, neutral protease and proteinase K for their ACE inhibitory activity in skimmed goat and cow milk and identified the best one with higher ACE inhibitory activity. The degree of hydrolysis (DH of alcalase and proteinase K were much higher than flavourzyme, neutral protease for both skimmed goat and cow milk. Alcalase was the best enzyme to produce ACE inhibitory peptides from goat milk, with the ACE inhibitory activity 95.31%, while proteinase K was the optimal protease for hydrolyzing cow milk, with 81.28% ACE inhibitory activity. Furthermore, no correlation was obtained between the ACE inhibitory activity and DH for both goat and cow milk.

  17. Evidence that active protection following oral immunization of mice with live rotavirus is not dependent on neutralizing antibody.

    Science.gov (United States)

    Ward, R L; McNeal, M M; Sheridan, J F

    1992-05-01

    Studies were performed to determine whether active immunity against murine rotavirus (EDIM) infection of mice correlated with titers of neutralizing antibody to the challenge virus. Neonatal mice administered either murine or heterologous rotaviruses all developed diarrhea and high titers of serum rotavirus IgG. However, only mice given EDIM, the murine EB, or simian SA11-FEM strains were protected against EDIM infection when challenged 60 days later. Other serotype 3 strains (RRV, SA11-SEM), as well as strains belonging to serotypes 5 and 6 (OSU, NCDV, WC3), were not protective. Serum neutralizing antibody titers to EDIM were almost undetectable after rotavirus infection with any strain and could not, therefore, be correlated with protection. Likewise, intestinal neutralizing antibody titers were extremely low 21 days after EDIM infection, and by 60 days after inoculation, EDIM-infected mice had no greater intestinal neutralizing antibody titers than uninoculated controls. Mice inoculated with SA11-FEM as neonates had much higher serum rotavirus IgG responses than mice inoculated as adults, and only those infected with this virus as neonates were protected. Thus, although immunity to EDIM did not correlate with the presence of neutralizing antibody to EDIM, it did correlate with the overall magnitude of the immune response after inoculation with SA11-FEM.

  18. Evidence for rapid epithermal mineralization and coeval bimodal volcanism, Bruner Au-Ag property, NV USA

    Science.gov (United States)

    Baldwin, Dylan

    The character of Au-Ag mineralization and volcanic/hydrothermal relationships at the underexplored Miocene-age Bruner low-sulfidation epithermal Au-Ag deposit are elucidated using field and laboratory studies. Bruner is located in central Nevada within the Great Basin extensional province, near several major volcanic trends (Western Andesite, Northern Nevada Rift) associated with world-class Miocene-age epithermal Au-Ag provinces. Despite its proximity to several >1 Moz Au deposits, and newly discovered high-grade drill intercepts (to 117 ppm Au/1.5m), there is no published research on the deposit, the style of mineralization has not been systematically characterized, and vectors to mineralization remain elusive. By investigating the nature of mineralization and time-space relationships between volcanic/hydrothermal activity, the deposit has been integrated into a regional framework, and exploration targeting improved. Mineralization occurs within narrow quartz + adularia +/- pyrite veins that manifest as sheeted/stockwork zones, vein swarms, and rare 0.3-2 m wide veins hosted by two generations of Miocene high-K, high-silica rhyolite flow dome complexes overlying an andesite flow unit. The most prominent structural controls on veining are N­striking faults and syn-mineral basalt/rhyolite dikes. Productive veins have robust boiling indicators (high adularia content, bladed quartz after calcite, recrystallized colloform quartz bands), lack rhythmic banding, and contain only 1-2 stages; these veins overprint, or occur separately from another population of barren to weakly mineralized rhythmically banded quartz-only veins. Ore minerals consist of coarse Au0.5Ag 0.5 electrum, fine Au0.7Ag0.3 electrum, acanthite, uytenbogaardtite (Ag3AuS2) and minor embolite Ag(Br,Cl). Now deeply oxidized, veins typically contain <1% pyrite/goethite + Au-Ag minerals, with trace marcasite and microscopic Fe-poor sphalerite. Property-scale K-feldspar alteration related to a pre

  19. Development of An Epi-thermal Neutron Field for Fundamental Researches for BNCT with A DT Neutron Source

    Science.gov (United States)

    Osawa, Yuta; Imoto, Shoichi; Kusaka, Sachie; Sato, Fuminobu; Tanoshita, Masahiro; Murata, Isao

    2017-09-01

    Boron Neutron Capture Therapy (BNCT) is known to be a new promising cancer therapy suppressing influence against normal cells. In Japan, Accelerator Based Neutron Sources (ABNS) are being developed for BNCT. For the spread of ABNS based BNCT, we should characterize the neutron field beforehand. For this purpose, we have been developing a low-energy neutron spectrometer based on 3He position sensitive proportional counter. In this study, a new intense epi-thermal neutron field was developed with a DT neutron source for verification of validity of the spectrometer. After the development, the neutron field characteristics were experimentally evaluated by using activation foils. As a result, we confirmed that an epi-thermal neutron field was successfully developed suppressing fast neutrons substantially. Thereafter, the neutron spectrometer was verified experimentally. In the verification, although a measured detection depth distribution agreed well with the calculated distribution by MCNP, the unfolded spectrum was significantly different from the calculated neutron spectrum due to contribution of the side neutron incidence. Therefore, we designed a new neutron collimator consisting of a polyethylene pre-collimator and boron carbide neutron absorber and confirmed numerically that it could suppress the side incident neutrons and shape the neutron flux to be like a pencil beam.

  20. Development of An Epi-thermal Neutron Field for Fundamental Researches for BNCT with A DT Neutron Source

    Directory of Open Access Journals (Sweden)

    Osawa Yuta

    2017-01-01

    Full Text Available Boron Neutron Capture Therapy (BNCT is known to be a new promising cancer therapy suppressing influence against normal cells. In Japan, Accelerator Based Neutron Sources (ABNS are being developed for BNCT. For the spread of ABNS based BNCT, we should characterize the neutron field beforehand. For this purpose, we have been developing a low-energy neutron spectrometer based on 3He position sensitive proportional counter. In this study, a new intense epi-thermal neutron field was developed with a DT neutron source for verification of validity of the spectrometer. After the development, the neutron field characteristics were experimentally evaluated by using activation foils. As a result, we confirmed that an epi-thermal neutron field was successfully developed suppressing fast neutrons substantially. Thereafter, the neutron spectrometer was verified experimentally. In the verification, although a measured detection depth distribution agreed well with the calculated distribution by MCNP, the unfolded spectrum was significantly different from the calculated neutron spectrum due to contribution of the side neutron incidence. Therefore, we designed a new neutron collimator consisting of a polyethylene pre-collimator and boron carbide neutron absorber and confirmed numerically that it could suppress the side incident neutrons and shape the neutron flux to be like a pencil beam.

  1. A spin reversal system for polarized epithermal neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Bowman, J.D. [Los Alamos Nat. Lab., NM (United States); Penttilae, S.I. [Los Alamos Nat. Lab., NM (United States); Tippens, W.B. [University of Virginia, Charlottesville, VA 22903 (United States)

    1996-01-21

    The design and construction of a spin-reversal system for longitudinally polarized epithermal neutrons are presented. The design uses a static magnetic field parallel to the momentum of the neutron. The longitudinal field changes the direction at its midpoint. A transverse magnetic field is turned off to control the spin direction at the end of the spin flipper. The neutron spin is reversed with respect to both the neutron momentum and the static longitudinal field at the exit of the spin flipper. In the transverse field-on state the spin adiabatically follows the field direction and the spin direction is reversed. In the transverse field-off state the spin passes rapidly through the region where the solenoidal field reverses the sign and the spin direction is not reversed. With this design, the spins of an 8-cm-diameter beam of longitudinally polarized neutrons can be reversed with an efficiency greater than 88% over a range of neutron energies of more than four orders of magnitude. (orig.).

  2. New Heterofunctional Supports Based on Glutaraldehyde-Activation: A Tool for Enzyme Immobilization at Neutral pH.

    Science.gov (United States)

    Melo, Ricardo Rodrigues de; Alnoch, Robson Carlos; Vilela, Adriana Ferreira Lopes; Souza, Emanuel Maltempi de; Krieger, Nadia; Ruller, Roberto; Sato, Hélia Harumi; Mateo, Cesar

    2017-06-29

    Immobilization is an exciting alternative to improve the stability of enzymatic processes. However, part of the applied covalent strategies for immobilization uses specific conditions, generally alkaline pH, where some enzymes are not stable. Here, a new generation of heterofunctional supports with application at neutral pH conditions was proposed. New supports were developed with different bifunctional groups (i.e., hydrophobic or carboxylic/metal) capable of adsorbing biocatalysts at different regions (hydrophobic or histidine richest place), together with a glutaraldehyde group that promotes an irreversible immobilization at neutral conditions. To verify these supports, a multi-protein model system ( E. coli extract) and four enzymes ( Candida rugosa lipase, metagenomic lipase, β-galactosidase and β-glucosidase) were used. The immobilization mechanism was tested and indicated that moderate ionic strength should be applied to avoid possible unspecific adsorption. The use of different supports allowed the immobilization of most of the proteins contained in a crude protein extract. In addition, different supports yielded catalysts of the tested enzymes with different catalytic properties. At neutral pH, the new supports were able to adsorb and covalently immobilize the four enzymes tested with different recovered activity values. Notably, the use of these supports proved to be an efficient alternative tool for enzyme immobilization at neutral pH.

  3. Enhanced static ground power unit based on flying capacitor based h-bridge hybrid active-neutral-point-clamped converter

    DEFF Research Database (Denmark)

    Abarzadeh, Mostafa; Madadi Kojabadi, Hossein; Deng, Fujin

    2016-01-01

    Static power converters have various applications, such as static ground power units (GPUs) for airplanes. This study proposes a new configuration of a static GPU based on a novel nine-level flying capacitor h-bridge active-neutral-point-clamped (FCHB_ANPC) converter. The main advantages of the p......Static power converters have various applications, such as static ground power units (GPUs) for airplanes. This study proposes a new configuration of a static GPU based on a novel nine-level flying capacitor h-bridge active-neutral-point-clamped (FCHB_ANPC) converter. The main advantages...... demonstrate the validity and feasibility of the proposed converter and the modulation method under various operating conditions....

  4. Towards energy neutrality by optimising the activated sludge process of the WWTP Bochum-Ölbachtal.

    Science.gov (United States)

    Marner, S T; Schröter, D; Jardin, N

    2016-01-01

    As a result of Ruhrverband's regularly performed energy audits the wastewater treatment plant (WWTP) Bochum-Ölbachtal shows substantial deficits concerning energy efficiency. Due to the energy consumption of internal recirculation, mixers and return activated sludge (RAS) pumping the existing pre-denitrification process configuration offers a specific energy consumption for biological treatment of 23 kWh (PE · a)(-1). In order to optimise the energy situation and to improve the treatment efficiency, the process layout was changed completely to a three-stage step-feed process. By optimising the hydraulic conditions, it was possible to reconstruct the plant with a free flow throughout the whole biological treatment system without any additional pumping. The total investment costs for this process scheme were 3.9 million €. These costs could be partly offset against the wastewater charge paid (2.9 million €). Compared to the overall energy consumption before the process modification, today the energy consumption for biological treatment amounts to 12.4 kWh (PE · a)(-1). The highest saving potential has been achieved by optimising mixing and reducing the energy demand for internal recirculation and RAS pumping. In the case of the WWTP Bochum-Ölbachtal, the modification of the treatment process not only results in an improved energy situation but also increased the treatment efficiency in such a way that the nitrogen concentration in the effluent could be constantly kept below 5 mg L(-1) N(tot), which provides the basis for being exempted from the wastewater discharge for nitrogen. As a result of all these measures, the rate of self-sufficiency by using biogas from the digester in combined heat and power units has been increased substantially from 60% before process modifications to 97%. With the upcoming optimisation measures, a further increase of self-sufficiency is expected to finally achieve energy neutrality based on yearly averages. The example of the

  5. Generation and characterization of cross neutralizing human monoclonal antibody against 4 serotypes of dengue virus without enhancing activity

    Directory of Open Access Journals (Sweden)

    Subenya Injampa

    2017-11-01

    Full Text Available Background Dengue disease is a leading cause of illness and death in the tropics and subtropics. Most severe cases occur among patients secondarily infected with a different dengue virus (DENV serotype compared with that from the first infection, resulting in antibody-dependent enhancement activity (ADE. Our previous study generated the neutralizing human monoclonal antibody, D23-1B3B9 (B3B9, targeting the first domain II of E protein, which showed strong neutralizing activity (NT against all four DENV serotypes. However, at sub-neutralizing concentrations, it showed ADE activity in vitro. Methods In this study, we constructed a new expression plasmid using the existing IgG heavy chain plasmid as a template for Fc modification at position N297Q by site-directed mutagenesis. The resulting plasmid was then co-transfected with a light chain plasmid to produce full recombinant IgG (rIgG in mammalian cells (N297Q-B3B9. This rIgG was characterized for neutralizing and enhancing activity by using different FcγR bearing cells. To produce sufficient quantities of B3B9 rIgG for further characterization, CHO-K1 cells stably secreting N297Q-B3B9 rIgG were then established. Results The generated N297Q-B3B9 rIgG which targets the conserved N-terminal fusion loop of DENV envelope protein showed the same cross-neutralizing activity to all four DENV serotypes as those of wild type rIgG. In both FcγRI- and RII-bearing THP-1 cells and FcγRII-bearing K562 cells, N297Q-B3B9 rIgG lacked ADE activity against all DENV serotypes at sub-neutralizing concentrations. Fortunately, the N297Q-B3B9 rIgG secreted from stable cells showed the same patterns of NT and ADE activities as those of the N297Q-B3B9 rIgG obtained from transient expression against DENV2. Thus, the CHO-K1 stably expressing N297Q-B3B9 HuMAb can be developed as high producer stable cells and used to produce sufficient amounts of antibody for further characterization as a promising dengue therapeutic

  6. Cationic peptides from peptic hydrolysates of rice endosperm protein exhibit antimicrobial, LPS-neutralizing, and angiogenic activities.

    Science.gov (United States)

    Taniguchi, Masayuki; Kawabe, Junya; Toyoda, Ryu; Namae, Toshiki; Ochiai, Akihito; Saitoh, Eiichi; Tanaka, Takaaki

    2017-11-01

    In this study, we hydrolyzed rice endosperm protein (REP) with pepsin and generated 20 fractions containing multifunctional cationic peptides with varying isoelectric point (pI) values using ampholyte-free isoelectric focusing (autofocusing). Subsequently, we determined antimicrobial activities of each fraction against the pathogens Prophyromonas gingivalis, Propionibacterium acnes, Streptocossus mutans, and Candida albicans. Fractions 18, 19, and 20 had pI values greater than 12 and exhibited antimicrobial activity against P. gingivalis, P. acnes, and C. albicans, but not against S. mutans. In further experiments, we purified and identified cationic peptides from fractions 18, 19, and 20 using reversed-phase high-performance liquid chromatography and matrix-assisted laser/desorption ionization-time-of-flight mass spectroscopy. We also chemically synthesized five identified peptides (RSVSKSR, RRVIEPR, ERFQPMFRRPG, RVRQNIDNPNRADTYNPRAG, and VVRRVIEPRGLL) with pI values greater than 10.5 and evaluated antimicrobial, lipopolysaccharide (LPS)-neutralizing, and angiogenic activities. Among these synthetic peptides, only VVRRVIEPRGLL exhibited antimicrobial activity against P. gingivalis, with an IC 50 value of 87μM. However, all five cationic peptides exhibited LPS-neutralizing and angiogenic activities with little or no hemolytic activity against mammalian red blood cells at functional concentrations. These present data show dual or multiple functions of the five identified cationic peptides with little or no hemolytic activity. Therefore, fractions containing cationic peptides from REP hydrolysates have the potential to be used as dietary supplements and functional ingredients in food products. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Experimental demonstration of a compact epithermal neutron source based on a high power laser

    Science.gov (United States)

    Mirfayzi, S. R.; Alejo, A.; Ahmed, H.; Raspino, D.; Ansell, S.; Wilson, L. A.; Armstrong, C.; Butler, N. M. H.; Clarke, R. J.; Higginson, A.; Kelleher, J.; Murphy, C. D.; Notley, M.; Rusby, D. R.; Schooneveld, E.; Borghesi, M.; McKenna, P.; Rhodes, N. J.; Neely, D.; Brenner, C. M.; Kar, S.

    2017-07-01

    Epithermal neutrons from pulsed-spallation sources have revolutionised neutron science allowing scientists to acquire new insight into the structure and properties of matter. Here, we demonstrate that laser driven fast (˜MeV) neutrons can be efficiently moderated to epithermal energies with intrinsically short burst durations. In a proof-of-principle experiment using a 100 TW laser, a significant epithermal neutron flux of the order of 105 n/sr/pulse in the energy range of 0.5-300 eV was measured, produced by a compact moderator deployed downstream of the laser-driven fast neutron source. The moderator used in the campaign was specifically designed, by the help of MCNPX simulations, for an efficient and directional moderation of the fast neutron spectrum produced by a laser driven source.

  8. Clinical laboratory application of a reporter-gene assay for measurement of functional activity and neutralizing antibody response to infliximab.

    Science.gov (United States)

    Pavlov, Igor Y; Carper, James; Lázár-Molnár, Eszter; Delgado, Julio C

    2016-01-30

    TNF-α antagonists such as infliximab are effective for the treatment of inflammatory bowel disease and other inflammatory and autoimmune diseases. Development of an immune response and subsequent neutralizing antibodies against these protein-based drugs is a major impediment that contributes to therapeutic failure, or adverse effects such as hypersensitivity reactions. As opposed to empirical dose-escalation strategies, rational and cost-effective evaluation of clinical non-responsiveness includes measurement of serum drug levels, and detection of drug-specific antibodies. We present the validation and 2-y experience using a functional, cell-based reporter gene assay (RGA) developed for measuring the biological activity and antibody response to serum infliximab. The RGA was used to test 4699 clinical specimens from patients suspected of therapeutic failure. In contrast to binding assays, which detect an overall antibody response, the RGA specifically detects those antibodies that have drug-neutralizing function, and thus, poses higher risk for therapeutic failure. The RGA presented here is currently the only functional clinical test available to measure serum infliximab activity and neutralizing antibodies. Due to its accuracy and precision, and suitability for high-throughput testing, this robust platform can be applied to any TNF-α antagonist, providing an invaluable tool for the clinical management of patients with treatment failure. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Pattern recognition analyses of brain activation elicited by happy and neutral faces in unipolar and bipolar depression

    Science.gov (United States)

    Mourão-Miranda, Janaina; Almeida, Jorge RC; Hassel, Stefanie; de Oliveira, Leticia; Versace, Amelia; Marquand, Andre F; Sato, Joao R; Brammer, Michael; Phillips, Mary L

    2012-01-01

    Objectives Recently, pattern recognition approaches have been used to classify patterns of brain activity elicited by sensory or cognitive processes. In the clinical context, these approaches have been mainly applied to classify groups of individuals based on structural magnetic resonance imaging (MRI) data. Only a few studies have applied similar methods to functional MRI (fMRI) data. Methods We used a novel analytic framework to examine the extent to which unipolar and bipolar depressed individuals differed on discrimination between patterns of neural activity for happy and neutral faces. We used data from 18 currently depressed individuals with bipolar I disorder (BD) and 18 currently depressed individuals with recurrent unipolar depression (UD), matched on depression severity, age, and illness duration, and 18 age- and gender ratio-matched healthy comparison subjects (HC). fMRI data were analyzed using a general linear model and Gaussian process classifiers. Results The accuracy for discriminating between patterns of neural activity for happy versus neutral faces overall was lower in both patient groups relative to HC. The predictive probabilities for intense and mild happy faces were higher in HC than in BD, and for mild happy faces were higher in HC than UD (all p < 0.001). Interestingly, the predictive probability for intense happy faces was significantly higher in UD than BD (p = 0.03). Conclusions These results indicate that patterns of whole-brain neural activity to intense happy faces were significantly less distinct from those for neutral faces in BD than in either HC or UD. These findings indicate that pattern recognition approaches can be used to identify abnormal brain activity patterns in patient populations and have promising clinical utility as techniques that can help to discriminate between patients with different psychiatric illnesses. PMID:22631624

  10. Differential neutralizing activities of a single domain camelid antibody (VHH specific for ricin toxin's binding subunit (RTB.

    Directory of Open Access Journals (Sweden)

    Cristina Herrera

    Full Text Available Ricin, a member of the A-B family of ribosome-inactivating proteins, is classified as a Select Toxin by the Centers for Disease Control and Prevention because of its potential use as a biothreat agent. In an effort to engineer therapeutics for ricin, we recently produced a collection of alpaca-derived, heavy-chain only antibody VH domains (VHH or "nanobody" specific for ricin's enzymatic (RTA and binding (RTB subunits. We reported that one particular RTB-specific VHH, RTB-B7, when covalently linked via a peptide spacer to different RTA-specific VHHs, resulted in heterodimers like VHH D10/B7 that were capable of passively protecting mice against a lethal dose challenge with ricin. However, RTB-B7 itself, when mixed with ricin at a 1 ∶ 10 toxin:antibody ratio did not afford any protection in vivo, even though it had demonstrable toxin-neutralizing activity in vitro. To better define the specific attributes of antibodies associated with ricin neutralization in vitro and in vivo, we undertook a more thorough characterization of RTB-B7. We report that RTB-B7, even at 100-fold molar excess (toxin:antibody was unable to alter the toxicity of ricin in a mouse model. On the other hand, in two well-established cytotoxicity assays, RTB-B7 neutralized ricin with a 50% inhibitory concentration (IC50 that was equivalent to that of 24B11, a well-characterized and potent RTB-specific murine monoclonal antibody. In fact, RTB-B7 and 24B11 were virtually identical when compared across a series of in vitro assays, including adherence to and neutralization of ricin after the toxin was pre-bound to cell surface receptors. RTB-B7 differed from both 24B11 and VHH D10/B7 in that it was relatively less effective at blocking ricin attachment to receptors on host cells and was not able to form high molecular weight toxin:antibody complexes in solution. Whether either of these activities is important in ricin toxin neutralizing activity in vivo remains to be determined.

  11. Isolation of a human-like antibody fragment (scFv that neutralizes ricin biological activity

    Directory of Open Access Journals (Sweden)

    Thullier Philippe

    2009-06-01

    Full Text Available Abstract Background Ricin is a lethal toxin that inhibits protein synthesis. It is easily extracted from a ubiquitously grown plant, Ricinus communis, and thus readily available for use as a bioweapon (BW. Anti-ricin antibodies provide the only known therapeutic against ricin intoxication. Results In this study, after immunizing a non-human primate (Macaca fascicularis with the ricin chain A (RTA, a phage-displayed immune library was built (2 × 108 clones, that included the λ light chain fragment. The library was screened against ricin, and specific binders were sequenced and further analyzed. The best clone, 43RCA, was isolated using a new, stringent neutralization test. 43RCA had a high, picomolar affinity (41 pM and neutralized ricin efficiently (IC50 = 23 ± 3 ng/ml, corresponding to a [scFv]/[ricin] molar ratio of 4. The neutralization capacity of 43RCA compared favourably with that of polyclonal anti-deglycosylated A chain (anti-dgRCA IgGs, obtained from hyperimmune mouse serum, which were more efficient than any monoclonal at our disposal. The 43RCA sequence is very similar to that for human IgG germline genes, with 162 of 180 identical amino acids for the VH and VL (90% sequence identity. Conclusion Results of the characterization studies, and the high degree of identity with human germline genes, altogether make this anti-ricin scFv, or an IgG derived from it, a likely candidate for use in humans to minimize effects caused by ricin intoxication.

  12. Canine distemper virus neutralization activity is low in human serum and it is sensitive to an amino acid substitution in the hemagglutinin protein

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xinsheng, E-mail: xzhang@iavi.org [AIDS Vaccine Design and Development Laboratory, International AIDS Vaccine Initiative (IAVI), Brooklyn, NY (United States); Molecular and Cellular Biology Program, State University of New York, Brooklyn, NY (United States); Wallace, Olivia L.; Domi, Arban; Wright, Kevin J.; Driscoll, Jonathan [AIDS Vaccine Design and Development Laboratory, International AIDS Vaccine Initiative (IAVI), Brooklyn, NY (United States); Anzala, Omu [Kenya AIDS Vaccine Initiative (KAVI)-Institute of Clinical Research, Nairobi (Kenya); Sanders, Eduard J. [Centre for Geographic Medicine Research, Kenya Medical Research Institute (KEMRI), Kilifi, Kenya & Centre for Clinical Vaccinology and Tropical Medicine, University of Oxford, Headington (United Kingdom); Kamali, Anatoli [MRC/UVRI Uganda Virus Research Unit on AIDS, Masaka and Entebbe (Uganda); Karita, Etienne [Projet San Francisco, Kigali (Rwanda); Allen, Susan [Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA (United States); Fast, Pat [Department of Medical Affairs, International AIDS Vaccine Initiative, NY, NY (United States); Gilmour, Jill [Human Immunology Laboratory, International AIDS Vaccine Initiative, London (United Kingdom); Price, Matt A. [Department of Medical Affairs, International AIDS Vaccine Initiative, NY, NY (United States); Department of Epidemiology and Biostatistics, University of California at San Francisco, San Francisco, CA (United States); Parks, Christopher L. [AIDS Vaccine Design and Development Laboratory, International AIDS Vaccine Initiative (IAVI), Brooklyn, NY (United States); Molecular and Cellular Biology Program, State University of New York, Brooklyn, NY (United States)

    2015-08-15

    Serum was analyzed from 146 healthy adult volunteers in eastern Africa to evaluate measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb) prevalence and potency. MV plaque reduction neutralization test (PRNT) results indicated that all sera were positive for MV nAbs. Furthermore, the 50% neutralizing dose (ND50) for the majority of sera corresponded to antibody titers induced by MV vaccination. CDV nAbs titers were low and generally were detected in sera with high MV nAb titers. A mutant CDV was generated that was less sensitive to neutralization by human serum. The mutant virus genome had 10 nucleotide substitutions, which coded for single amino acid substitutions in the fusion (F) and hemagglutinin (H) glycoproteins and two substitutions in the large polymerase (L) protein. The H substitution occurred in a conserved region involved in receptor interactions among morbilliviruses, implying that this region is a target for cross-reactive neutralizing antibodies. - Highlights: • Screened 146 serum samples for measles virus (MV) and canine distemper virus (CDV) neutralizing antibody (nAb). • MV nAb is prevalent in the sera. • CDV neutralizing activity is generally low or absent and when detected it is present in sera with high MV nAb titers. • A neutralization-resistant CDV mutant was isolated using human serum selection. • A mutation was identified in the receptor-binding region of CDV hemagglutinin protein that confers the neutralization resistance.

  13. Superior labral anterior-to-posterior lesions: comparison of external rotation and active supination CT arthrography with neutral CT arthrography.

    Science.gov (United States)

    Choi, Ja-Young; Kim, Sae Hoon; Yoo, Hye Jin; Shin, Seung Han; Oh, Joo Han; Baek, Goo Hyun; Hong, Sung Hwan

    2012-04-01

    To compare the diagnostic performance of computed tomographic (CT) arthrography performed with external rotation and active supination (ERAS) with that of CT angiography performed in the neutral position for superior labral anterior-to-posterior (SLAP) lesions. Institutional review board approval and informed consent were obtained. CT arthrography in neutral and ERAS positions was performed in 49 shoulders of 47 patients, with subsequent arthroscopic confirmation of the status of the superior labrum. Two musculoskeletal radiologists (1 and 8 years of experience) reviewed images and expressed the likelihood of SLAP lesions by using a continuous scale; they also measured gap widths and depths of labral detachment. Overall performances for the detection of SLAP lesions were determined with receiver-operating characteristic (ROC) analysis. Gap widths and depths measured with the two types of CT arthrography were also compared. For reader 1, area under the ROC curve increased insignificantly from 0.932 in the neutral position to 0.974 in the ERAS position (P = .210), whereas for reader 2, it increased significantly from 0.914 to 0.984 (P = .032). Mean gap width of SLAP lesion was significantly greater according to ERAS CT arthrography (3.98 mm ± 2.48 [standard deviation] vs 1.61 mm ± 1.11), whereas mean gap depth was not significantly different. Gap width and depth cutoff values for the detection of a SLAP lesion with ERAS CT arthrography were 1.7 mm and 1.6 mm, respectively. ERAS CT arthrography might improve the detection of SLAP lesions compared with neutral-position CT arthrography. © RSNA, 2012.

  14. Effects of acute psychosocial stress on neural activity to emotional and neutral faces in a face recognition memory paradigm.

    Science.gov (United States)

    Li, Shijia; Weerda, Riklef; Milde, Christopher; Wolf, Oliver T; Thiel, Christiane M

    2014-12-01

    Previous studies have shown that acute psychosocial stress impairs recognition of declarative memory and that emotional material is especially sensitive to this effect. Animal studies suggest a central role of the amygdala which modulates memory processes in hippocampus, prefrontal cortex and other brain areas. We used functional magnetic resonance imaging (fMRI) to investigate neural correlates of stress-induced modulation of emotional recognition memory in humans. Twenty-seven healthy, right-handed, non-smoker male volunteers performed an emotional face recognition task. During encoding, participants were presented with 50 fearful and 50 neutral faces. One hour later, they underwent either a stress (Trier Social Stress Test) or a control procedure outside the scanner which was followed immediately by the recognition session inside the scanner, where participants had to discriminate between 100 old and 50 new faces. Stress increased salivary cortisol, blood pressure and pulse, and decreased the mood of participants but did not impact recognition memory. BOLD data during recognition revealed a stress condition by emotion interaction in the left inferior frontal gyrus and right hippocampus which was due to a stress-induced increase of neural activity to fearful and a decrease to neutral faces. Functional connectivity analyses revealed a stress-induced increase in coupling between the right amygdala and the right fusiform gyrus, when processing fearful as compared to neutral faces. Our results provide evidence that acute psychosocial stress affects medial temporal and frontal brain areas differentially for neutral and emotional items, with a stress-induced privileged processing of emotional stimuli.

  15. Fishbone activity in experimental advanced superconducting tokamak neutral beam injection plasma

    Science.gov (United States)

    Xu, Liqing; Zhang, Jizong; Chen, Kaiyun; Hu, Liqun; Li, Erzhong; Lin, Shiyao; Shi, Tonghui; Duan, Yanmin; Zhu, Yubao

    2015-12-01

    Repetitive fishbones near the trapped ion procession frequency were observed for the first time in the neutral beam injection high confinement plasmas in Experimental Advanced Superconducting Tokamak (EAST) tokamak, and diagnosed using a solid-state neutral particle analyzer based on a compact silicon photodiode together with an upgraded high spatial-temporal-resolution multi-arrays soft X-ray (SX) system. This 1/1 typical internal kink mode propagates in the ion-diamagnetism direction with a rotation speed faster than the bulk plasma in the plasma frame. From the SX measurements, this mode frequency is typical of chirping down and the energetic particle effect related to the twisting mode structure. This ion fishbone was found able to trigger a multiple core sawtooth crashes with edge-2/1 sideband modes, as well as to lead to a transition from fishbone to long lived saturated kink mode to fishbone. Furthermore, using SX tomography, a correlation between mode amplitude and mode frequency was found. Finally, a phenomenological prey-predator model was found to reproduce the fishbone nonlinear process well.

  16. N-terminal amino acids of bovine alpha interferons are relevant for the neutralization of their antiviral activity

    Directory of Open Access Journals (Sweden)

    J.B. Barreto Filho

    2001-05-01

    Full Text Available The structure-function relationship of interferons (IFNs has been studied by epitope mapping. Epitopes of bovine IFNs, however, are practically unknown, despite their importance in virus infections and in the maternal recognition of pregnancy. It has been shown that recombinant bovine (rBoIFN-alphaC and rBoIFN-alpha1 differ only in 12 amino acids and that the F12 monoclonal antibody (mAb binds to a linear sequence of residues 10 to 34. We show here that the antiviral activities of these two IFNs were neutralized by the F12 mAb to different extents using two tests. In residual activity tests the antiviral activity dropped by more than 99% with rBoIFN-alphaC and by 84% with rBoIFN-alpha1. In checkerboard antibody titrations, the F12 mAb titer was 12,000 with rBoIFN-alphaC and only 600 with rBoIFN-alpha1. Since these IFNs differ in their amino acid sequence at positions 11, 16 and 19 of the amino terminus, only these amino acids could account for the different neutralization titers, and they should participate in antibody binding. According to the three-dimensional structure described for human and murine IFNs, these amino acids are located in the alpha helix A; amino acids 16 and 19 of the bovine IFNs would be expected to be exposed and could bind to the antibody directly. The amino acid at position 11 forms a hydrogen bond in human IFNs-alpha and it is possible that, in bovine IFNs-alpha, the F12 mAb, binding near position 11, would disturb this hydrogen bond, resulting in the difference in the extent of neutralization observed.

  17. Formulation and anti-neurotoxic activity of baicalein-incorporating neutral nanoliposome

    DEFF Research Database (Denmark)

    Aliakbari, Farhang; Shabani, Ali Akbar; Bardania, Hassan

    2017-01-01

    's and Alzheimer's. However, therapeutic usage in vivo is challenged by low solubility and stability. To address this we have applied neutrally-charged nanoliposome (NLP) as carrier for baicalein. Baicalein was incorporated into NLP to form NLP-Ba at molar baicalain:lipid ratios of up to 1:3, giving a drug...... entrapment efficiency of 96.71%, slow release of approximately 22% after a week and increased baicalein stability up to 27%. Ascorbic acid increased baicalein's stability further, particularly when incorporated in NLP where baicalein stability intensified by 53% in NLP-Ba. Moreover, NLP-Ba did not show...... significant cytotoxic effects against neurons; rather, showed considerable protective effect against reactive oxygen species. In addition, NLP promoted internalization of baicalein into cells, showing good biocompatibility. We conclude that NLP-Ba can enhance baicalein's therapeutic potential...

  18. Specifically modified Env immunogens activate B-cell precursors of broadly neutralizing HIV-1 antibodies in transgenic mice

    Science.gov (United States)

    McGuire, Andrew T.; Gray, Matthew D.; Dosenovic, Pia; Gitlin, Alexander D.; Freund, Natalia T.; Petersen, John; Correnti, Colin; Johnsen, William; Kegel, Robert; Stuart, Andrew B.; Glenn, Jolene; Seaman, Michael S.; Schief, William R.; Strong, Roland K.; Nussenzweig, Michel C.; Stamatatos, Leonidas

    2016-01-01

    VRC01-class broadly neutralizing HIV-1 antibodies protect animals from experimental infection and could contribute to an effective vaccine response. Their predicted germline forms (gl) bind Env inefficiently, which may explain why they are not elicited by HIV-1 Env-immunization. Here we show that an optimized Env immunogen can engage multiple glVRC01-class antibodies. Furthermore, this immunogen activates naive B cells expressing the human germline heavy chain of 3BNC60, paired with endogenous mouse light chains in vivo. To address whether it activates B cells expressing the fully humanized gl3BNC60 B-cell receptor (BCR), we immunized mice carrying both the heavy and light chains of gl3BNC60. B cells expressing this BCR display an autoreactive phenotype and fail to respond efficiently to soluble forms of the optimized immunogen, unless it is highly multimerized. Thus, specifically designed Env immunogens can activate naive B cells expressing human BCRs corresponding to precursors of broadly neutralizing HIV-1 antibodies even when the B cells display an autoreactive phenotype. PMID:26907590

  19. Studies on the properties of an epithermal-neutron hydrogen analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Papp, A., E-mail: papppa@atomki.h [Institute of Nuclear Research of the Hungarian Academy of Sciences, Pf. 51, 4001 Debrecen (Hungary); Csikai, J. [Institute of Nuclear Research of the Hungarian Academy of Sciences, Pf. 51, 4001 Debrecen (Hungary); Institute of Experimental Physics, University of Debrecen, Pf. 105, 4010 Debrecen-10 (Hungary)

    2010-09-15

    Systematic investigations have proved the advantages of the Epithermal Neutron Analyzer (ETNA) for bulk hydrogen analysis as compared to the thermal neutron techniques. Results can contribute, for example, to the design and construction of instruments needed for the detection and identification of plastic anti-personnel landmines, explosives hidden in airline baggage and cargo containers via hydrogen contents as an indicator of their presence.

  20. Fine Structure Discussion of Parity-Nonconserving Neutron Scattering at Epithermal Energies

    OpenAIRE

    Hussein, M. S.; Kerman, A. K.; Lin, C-Y

    1994-01-01

    The large magnitude and the sign correlation effect in the parity non-conserving resonant scattering of epithermal neutrons from $^{232}$Th is discussed in terms of a non-collective $2p-1h$ local doorway model. General conclusions are drawn as to the probability of finding large parity violation effects in other regions of the periodic table.

  1. Antivenomics of Atropoides mexicanus and Atropoides picadoi snake venoms: Relationship to the neutralization of toxic and enzymatic activities.

    Science.gov (United States)

    Antúnez, José; Fernández, Julián; Lomonte, Bruno; Angulo, Yamileth; Sanz, Libia; Pérez, Alicia; Calvete, Juan José; Gutiérrez, José María

    2010-09-30

    Viperid snakes of the genus Atropoides are distributed in Mexico and Central America and, owing to their size and venom yield, are capable of provoking severe envenomings in humans. This study evaluated, using an 'antivenomics' approach, the ability of a polyspecific (polyvalent) antivenom manufactured in Costa Rica to recognize the proteins of Atropoides mexicanus and A. picadoi venoms, which are not included in the immunization mixture. In addition, the neutralization of lethal, hemorrhagic, myotoxic, coagulant, proteinase and phospholipase A(2) (PLA(2)) activities of these venoms by the antivenom was assessed. The antivenom was highly-effective in immunodepleting many venom components, particularly high molecular mass P-III metalloproteinases (SVMPs), L-amino acid oxidases, and some serine proteinases and P-I SVMPs. In contrast, PLA(2)s, certain serine proteinases and P-I SVMPs, and a C type lectin-like protein were only partially immunodepleted, and two PLA(2) molecules were not depleted at all. The antivenom was able to neutralize all toxic and enzymatic activities tested, although neutralization of lethality by A. nummifer venom was achieved when a challenge dose of 3 LD(50)s of venom was used, but was iffective when 4 LD(50)s were used. These results, and previously obtained evidence on the immunoreactivity of this antivenom towards homologous and heterologous venoms, revealed the low immunogenicity of a number of venom components (PLA(2)s, CRISPs, P-I SVMPs, and some serine proteinases), underscoring the need to search for innovative immunization protocols to improve the immune response to these antigens.

  2. First evidence of epithermal gold occurrences in the SE Afar Rift, Republic of Djibouti

    Science.gov (United States)

    Moussa, N.; Fouquet, Y.; Le Gall, B.; Caminiti, A. M.; Rolet, J.; Bohn, M.; Etoubleau, J.; Delacourt, C.; Jalludin, M.

    2012-06-01

    The geology of the Republic of Djibouti, in the SE Afar Triangle, is characterized by intense tectonic and bimodal volcanic activity that began as early as 25-30 Ma. Each magmatic event was accompanied by hydrothermal activity. Mineralization generally occurs as gold-silver bearing chalcedony veins and is associated with felsic volcanism. Eighty samples from mineralized hydrothermal chalcedony, quartz ± carbonate veins and breccias were studied from ten sites representing four major volcanic events that range in age from early Miocene to the present. The most recent veins are controlled by fractures at the edges of grabens established during the last 4 Myr. Gold in excess of 200 ppb is present in 30% of the samples, with values up to 16 ppm. Mineralogical compositions allowed us to identify different types of mineralization corresponding to different depths in the hydrothermal system: (1) surface and subsurface mineralization characterized by carbonate chimneys, gypsum, silica cap and quartz ± carbonate veins that are depleted in metals and Au; (2) shallow banded chalcedony ± adularia veins related to boiling that contain up to 16 ppm Au, occurring as native gold and electrum with pyrite, and tetradymite; (3) quartz veins with sulfides, and (4) epidote alteration in the deepest hydrothermal zones. Samples in which pyrite is enriched in As tend to have a high Au content. The association with bimodal volcanism, the occurrence of adularia and the native Au and electrum in banded chalcedony veins are typical of epithermal systems and confirm that this type of mineralization can occur in a young intracontinental rift system.

  3. The geochemistry of host arc volcanic rocks to the Co-O epithermal gold deposit, Eastern Mindanao, Philippines

    Science.gov (United States)

    Sonntag, Iris; Kerrich, Robert; Hagemann, Steffen G.

    2011-12-01

    between the forearc and arc axis, followed by a calc-alkaline convergent margin magma suite involving shallower crustal AFC near the central arc sector. The analysed Oligocene arc segment is related to a potentially steep to intermediate dipping subduction zone in an extensional to neutral geotectonic regime. The large subduction accretion complex of the Philippine Mobile Belt provides an ideal setting for significant metal deposits during its entire evolution. This is evidenced in the Eastern Mindanao Ridge, which hosts substantial porphyry Cu and epithermal Au deposits.

  4. Divergent Trends of Anti-JCPyV Serum Reactivity and Neutralizing Activity in Multiple Sclerosis (MS Patients during Treatment with Natalizumab

    Directory of Open Access Journals (Sweden)

    Roberta Antonia Diotti

    2016-05-01

    Full Text Available The association between natalizumab and progressive multifocal leukoencephalopathy (PML is established, but a reliable clinical risk stratification flow-chart is lacking. New risk factors are needed, such as the possible role of the anti-JC polyomavirus (JCPyV neutralizing antibody. In this pilot study, we analyzed this parameter during natalizumab treatment. Sequential sera of 38 multiple sclerosis patients during their first year of natalizumab treatment were collected, and grouped according to the number of infusions. For 11 patients, samples were also available after 24 infusions (T24, when progressive multifocal leukoencephalopathy (PML risk is higher. The reactivity against VP1, the main JCPyV surface protein, and the anti-JCPyV neutralizing activity were evaluated. During the first year, a lack of correlation between anti-JCPyV antibody response and its neutralizing activity was observed: a significant decrease in anti-JCPyV antibody response was observed (p = 0.0039, not paralleled by a similar trend in the total anti-JCPyV neutralizing activity (p = 0.2239. This lack of correlation was even more evident at T24 when, notwithstanding a significant increase in the anti-JCPyV response (p = 0.0097, a further decrease of the neutralizing activity was observed (p = 0.0062. This is the first study evidencing, prospectively, the lack of correlation between the anti-JCPyV antibody response and its neutralizing activity during natalizumab treatment.

  5. Lithologic controls on mineralization at the Lagunas Norte high-sulfidation epithermal gold deposit, northern Peru

    Science.gov (United States)

    Cerpa, Luis M.; Bissig, Thomas; Kyser, Kurt; McEwan, Craig; Macassi, Arturo; Rios, Hugo W.

    2013-06-01

    The 13.1-Moz high-sulfidation epithermal gold deposit of Lagunas Norte, Alto Chicama District, northern Peru, is hosted in weakly metamorphosed quartzites of the Upper Jurassic to Lower Cretaceous Chimú Formation and in overlying Miocene volcanic rocks of dacitic to rhyolitic composition. The Dafne and Josefa diatremes crosscut the quartzites and are interpreted to be sources of the pyroclastic volcanic rocks. Hydrothermal activity was centered on the diatremes and four hydrothermal stages have been defined, three of which introduced Au ± Ag mineralization. The first hydrothermal stage is restricted to the quartzites of the Chimú Formation and is characterized by silice parda, a tan-colored aggregate of quartz-auriferous pyrite-rutile ± digenite infilling fractures and faults, partially replacing silty beds and forming cement of small hydraulic breccia bodies. The δ34S values for pyrite (1.7-2.2 ‰) and digenite (2.1 ‰) indicate a magmatic source for the sulfur. The second hydrothermal stage resulted in the emplacement of diatremes and the related volcanic rocks. The Dafne diatreme features a relatively impermeable core dominated by milled slate from the Chicama Formation, whereas the Josefa diatreme only contains Chimú Formation quartzite clasts. The third hydrothermal stage introduced the bulk of the mineralization and affected the volcanic rocks, the diatremes, and the Chimú Formation. In the volcanic rocks, classic high-sulfidation epithermal alteration zonation exhibiting vuggy quartz surrounded by a quartz-alunite and a quartz-alunite-kaolinite zone is observed. Company data suggest that gold is present in solid solution or micro inclusions in pyrite. In the quartzite, the alteration is subtle and is manifested by the presence of pyrophyllite or kaolinite in the silty beds, the former resulting from relatively high silica activities in the fluid. In the quartzite, gold mineralization is hosted in a fracture network filled with coarse alunite

  6. Formulation and anti-neurotoxic activity of baicalein-incorporating neutral nanoliposome.

    Science.gov (United States)

    Aliakbari, Farhang; Shabani, Ali Akbar; Bardania, Hassan; Mohammad-Beigi, Hossein; Tayaranian Marvian, Amir; Dehghani Esmatabad, Faezeh; Vafaei, Abbas Ali; Shojaosadati, Seyed Abbas; Saboury, Ali Akbar; Christiansen, Gunna; Otzen, Daniel E; Morshedi, Dina

    2017-11-11

    Despite extensive studies of the effects of herbal-derived small molecules in the biopharmaceutical and biomedical sciences, their low solubility and stability remain a challenge. Here we focus on baicalein, a small molecule showing potential against neurodegenerative diseases such as Parkinson's and Alzheimer's. However, therapeutic usage in vivo is challenged by low solubility and stability. To address this we have applied neutrally-charged nanoliposome (NLP) as carrier for baicalein. Baicalein was incorporated into NLP to form NLP-Ba at molar baicalain:lipid ratios of up to 1:3, giving a drug entrapment efficiency of 96.71%, slow release of approximately 22% after a week and increased baicalein stability up to 27%. Ascorbic acid increased baicalein's stability further, particularly when incorporated in NLP where baicalein stability intensified by 53% in NLP-Ba. Moreover, NLP-Ba did not show significant cytotoxic effects against neurons; rather, showed considerable protective effect against reactive oxygen species. In addition, NLP promoted internalization of baicalein into cells, showing good biocompatibility. We conclude that NLP-Ba can enhance baicalein's therapeutic potential in neurodegenerative diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Broadening of neutralization activity to directly block a dominant antibody-driven SARS-coronavirus evolution pathway.

    Science.gov (United States)

    Sui, Jianhua; Aird, Daniel R; Tamin, Azaibi; Murakami, Akikazu; Yan, Meiying; Yammanuru, Anuradha; Jing, Huaiqi; Kan, Biao; Liu, Xin; Zhu, Quan; Yuan, Qing-An; Adams, Gregory P; Bellini, William J; Xu, Jianguo; Anderson, Larry J; Marasco, Wayne A

    2008-11-01

    Phylogenetic analyses have provided strong evidence that amino acid changes in spike (S) protein of animal and human SARS coronaviruses (SARS-CoVs) during and between two zoonotic transfers (2002/03 and 2003/04) are the result of positive selection. While several studies support that some amino acid changes between animal and human viruses are the result of inter-species adaptation, the role of neutralizing antibodies (nAbs) in driving SARS-CoV evolution, particularly during intra-species transmission, is unknown. A detailed examination of SARS-CoV infected animal and human convalescent sera could provide evidence of nAb pressure which, if found, may lead to strategies to effectively block virus evolution pathways by broadening the activity of nAbs. Here we show, by focusing on a dominant neutralization epitope, that contemporaneous- and cross-strain nAb responses against SARS-CoV spike protein exist during natural infection. In vitro immune pressure on this epitope using 2002/03 strain-specific nAb 80R recapitulated a dominant escape mutation that was present in all 2003/04 animal and human viruses. Strategies to block this nAb escape/naturally occurring evolution pathway by generating broad nAbs (BnAbs) with activity against 80R escape mutants and both 2002/03 and 2003/04 strains were explored. Structure-based amino acid changes in an activation-induced cytidine deaminase (AID) "hot spot" in a light chain CDR (complementarity determining region) alone, introduced through shuffling of naturally occurring non-immune human VL chain repertoire or by targeted mutagenesis, were successful in generating these BnAbs. These results demonstrate that nAb-mediated immune pressure is likely a driving force for positive selection during intra-species transmission of SARS-CoV. Somatic hypermutation (SHM) of a single VL CDR can markedly broaden the activity of a strain-specific nAb. The strategies investigated in this study, in particular the use of structural information in

  8. Origin of epithermal Ag-Au-Cu-Pb-Zn mineralization in Guanajuato, Mexico

    Science.gov (United States)

    Mango, Helen; Arehart, Greg; Oreskes, Naomi; Zantop, Half

    2014-01-01

    The Guanajuato epithermal district is one of the largest silver producers in Mexico. Mineralization occurs along three main vein systems trending dominantly northwest-southeast: the central Veta Madre, the La Luz system to the northwest, and the Sierra system to the east. Mineralization consists dominantly of silver sulfides and sulfosalts, base metal sulfides (mostly chalcopyrite, galena, sphalerite, and pyrite), and electrum. There is a broad zonation of metal distribution, with up to 10 % Cu+Pb+Zn in the deeper mines along the northern and central portions of the Veta Madre. Ore occurs in banded veins and breccias and as stockworks, with gangue composed dominantly of quartz and calcite. Host rocks are Mesozoic sedimentary and intrusive igneous rocks and Tertiary volcanic rocks. Most fluid inclusion homogenization temperatures are between 200 and 300 °C, with salinities below 4 wt.% NaCl equivalent. Fluid temperature and salinity decreased with time, from 290 to 240 °C and from 2.5 to 1.1 wt.% NaCl equivalent. Relatively constant fluid inclusion liquid-to-vapor ratios and a trend of decreasing salinity with decreasing temperature and with increasing time suggest dilution of the hydrothermal solutions. However, evidence of boiling (such as quartz and calcite textures and the presence of adularia) is noted along the Veta Madre, particularly at higher elevations. Fluid inclusion and mineralogical evidence for boiling of metal-bearing solutions is found in gold-rich portions of the eastern Sierra system; this part of the system is interpreted as the least eroded part of the district. Oxygen, carbon, and sulfur isotope analysis of host rocks, ore, and gangue minerals and fluid inclusion contents indicate a hydrothermal fluid, with an initial magmatic component that mixed over time with infiltrating meteoric water and underwent exchange with host rocks. Mineral deposition was a result of decreasing activities of sulfur and oxygen, decreasing temperature, increasing p

  9. Portovelo: a volcanic-hosted epithermal vein-system in Ecuador, South America

    Science.gov (United States)

    van Thournout, F.; Salemink, J.; Valenzuela, G.; Merlyn, M.; Boven, A.; Muchez, P.

    1996-05-01

    The Portovelo epithermal vein-system in southwestern Ecuador has produced more than 120 tons of gold and about 250 tons of silver. The veins result from hydrothermal processes close to a Miocene volcano which produced an andesitic to dacitic sequence followed by collapse and post-collapse rhyolitec activity which generated most of the alteration and mineralization. Three main structural segments are defined by NW-trending strike-slip faults, which show later stages of vertical movement. These faults are responsible for development of an extensive N-S dilatational jog within andesitic rocks, which acted as the main host to ore-deposition. A large-scale propylitic aureole surrounds a quartz-chloritesericite-adularia core, centered on the rhyolites, within a system of collapse-related ring-structures. A quartz-chlorite-sericite-adularia-calcite assemblage is the most common wall-rock alteration close to the veins. The size (4 × 15 km) and vertical range (1400 m) of the vein-system is exceptional. Alteration, textures and mineral assemblage, including a quartz-calcite gangue, sulfides, abundant sulfosalts and free gold (electrum), are quite typical of an adularia-sericite epithermal deposit. Spatially, the mineralization is arranged in three zones. In addition, three successive stages can be distinguished. The bulk of economic mineralization was deposited during the second stage, in association with a clear quartz and calcite gangue. Tm-ice and Tm-clath data of fluid inclusions in the clear quartz indicate a high salinity (˜ 10.5 eq. wt% NaCI). The homogenization temperatures of fluid inclusions in the gangue minerals and in the altered host-rocks vary between 180° and 310°C. Quartz δ 18O-values from hydrothermally altered wall-rocks reflect the original isotopic values of the latter. These values show a narrower range in vein quartz ( δO18 between +7.7‰ and +11.57‰ SMOW). In addition, the δO18 values of the vein quartz increase systematically with

  10. Epithermal mercury-antimony and gold-bearing vein lodes of southwestern Alaska

    Science.gov (United States)

    Gray, John E.; Gent, Carol A.; Snee, Lawrence W.; Wilson, Frederic H.; Goldfarb, Richard J.; Miller, Lance D.

    1997-01-01

    Epithermal mineral deposits and occurrences of southwestern Alaska consist of Hg-Sb and gold- and sulfide-bearing vein lodes. Numerous Hg-Sb lodes are located throughout a region measuring several tens of thousands of square kilometers in and surrounding the Kuskokwim River basin in southwestern Alaska. The Hg-Sb lodes are hosted in sedimentary rocks of the Cretaceous Kuskokwim Group, the Triassic to Cretaceous Gemuk Group, and the Paleozoic Holitna Group, as well as in Late Cretaceous and early Tertiary mafic to felsic intrusive rocks. Mineralized Hg-Sb vein and vein breccia lodes are found in the sedimentary or igneous rocks or at their contacts. The minerology of the Hg-Sb lodes is dominated by cinnabar and stibnite, with subordinate realgar, orpiment, and native mercury, pyrite, gold, and hematite, as well as solid and liquid hydrocarbons; quartz, carbonate, limonite, dickite, and sercite are alteration gangue minerals. The largest mercury mine in Alaska, Red Devil, produced about 36,000 flasks of mercury, but the Hg-Sb lodes of southwestern Alaska generally consist of small, discontinuous veins that rarely exceed a few meters in width and a few tens of meters in strike length. The Hg-Sb lodes generally contain about 1 to 5 percent Hg and less than 1 percent Sb and As but are generally poor in base emtals and precious metals. Anomalous concentrations of gold in some lodes, however, suggest that gold deposits may be present in higher temperature environments below some of the Hg-Sb lodes.The formation of the Hg-Sb lodes is closely correlated with igneous activity of a Late Cretaceous and early tertiary magmatic arc in southwestern Alaska. Geologic and geochemical characteristics of the Hg-Sb lodes suggest that ore fluids were generated in local sedimentary rocks as they were intruded by magmas. These intrusions provided the heat to initiate dehydration reactions and expel fluids from hydrous minerals and formational waters in the sedimentary rocks, causing

  11. Neutral currents

    CERN Document Server

    AUTHOR|(CDS)2069482

    1986-01-01

    The present status of weak neutral currents is reviewed. F.mphasis is put on the comparison of recent experimental results with earlier ones, and with predictions of gauge models of the SU(Z) ® U(l) type. The coupling constants governing the weak neutral current interaction are given, and their quantitative agreement with the Salam-Weinberg model is critically examined. 1. INrRODUCT ION 25 The last year has been a period of consolidation for neutral current physics. Important new results and improvements of old results have been reported, but our picture of the neutral current interaction did not change compared to that of one year ago 1 • 2). Hence the emphasis of this review is put on recent experimental results, and on a critical discussion of the precision of those experiments which yield the most stringent constraints on model parameters. The processes which can occur via the weak neutral current interaction are depicted in the "Sakurai tetragon" 3) which is shown in Fig. 1. It is an analogue to the P...

  12. The cross-neutralizing activity of enterovirus 71 subgenotype c4 vaccines in healthy chinese infants and children.

    Directory of Open Access Journals (Sweden)

    Qunying Mao

    Full Text Available BACKGROUND: EV71 is one of major etiologic causes of hand-foot-mouth disease (HFMD and leads to severe neurological complications in young children and infants. Recently inactivated EV71 vaccines have been developed by five manufactures and clinically show good safety and immunogenicity. However, the cross-neutralizing activity of these vaccines remains unclear, and is of particular interest because RNA recombination is seen more frequently in EV71 epidemics. METHODOLOGY/PRINCIPAL FINDINGS: In this post-hoc study, sera from a subset of 119 infants and children in two clinical trials of EV71 subgenotype C4 vaccines (ClinicalTrials.gov Identifier: NCT01313715 and NCT01273246, were detected for neutralizing antibody (NTAb titres with sera from infected patients as controls. Cytopathogenic effect method was employed to test NTAb against EV71 subgenotype B4, B5, C2, C4 and C5, which were prominent epidemic strains worldwide over the past decade. To validate the accuracy of the results, ELISpot assay was employed in parallel to detect NTAb in all the post-vaccine sera. After two-dose vaccination, 49 out of 53 participants in initially seronegative group and 52 out of 53 participants in initially seropositive group showed less than 4-fold differences in NTAb titers against five EV71 strains, whereas corresponding values among sera from pediatric patients recovering from EV71-induced HFMD and subclinically infected participants were 8/8 and 41/43, respectively. The geometric mean titers of participants against five subgenotypes EV71 all grew significantly after vaccinations, irrespective of the baseline NTAb titer. The relative fold increase in antibody titers (NTAb-FI against B4, B5, C2, and C5 displayed a positive correlation to the NTAb-FI against C4. CONCLUSIONS/SIGNIFICANCE: The results demonstrated broad cross-neutralizing activity induced by two C4 EV71 vaccines in healthy Chinese infants and children. However, the degree of induced cross

  13. Imaging of gamma and neutron dose distributions at LVR-15 epithermal beam by means of FGLDs

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G., E-mail: grazia.gambarini@mi.infn.it [Department of Physics, Universita degli Studi, Milan (Italy)] [INFN, Istituto Nazionale di Fisica Nucleare, Section of Milan, Milan (Italy); Bartesaghi, G. [Department of Physics, Universita degli Studi, Milan (Italy)] [INFN, Istituto Nazionale di Fisica Nucleare, Section of Milan, Milan (Italy); Carrara, M. [The Fondazione IRCCS ' Istituto Nazionale Tumori' , Milan (Italy); Negri, A. [INFN, Istituto Nazionale di Fisica Nucleare, Section of Milan, Milan (Italy); Paganini, L. [Department of Physics, Universita degli Studi, Milan (Italy); Vanossi, E. [INFN, Istituto Nazionale di Fisica Nucleare, Section of Milan, Milan (Italy); Burian, J.; Marek, M.; Viererbl, L.; Klupak, V.; Rejchrt, J. [Department of Reactor Physics, NRI Rez, plc (Czech Republic)

    2011-12-15

    Gamma and fast neutron dose spatial distributions have been measured at the collimator exit of the epithermal neutron beam of LVR-15 reactor (Rez). Measurements were performed by means of optically analyzed Fricke-gel-layer detectors. The separation of the two dose contributions has been achieved by suitable pixel-to-pixel elaboration of the light transmittance images of Fricke-gel-layer detectors prepared with water and heavy water.

  14. Identification and neutralization of biological activities associated with venom from the brown recluse spider, Loxosceles reclusa.

    Science.gov (United States)

    Futrell, J M; Morgan, P N

    1977-11-01

    Venom from the brown recluse spider, Loxosceles reclusa, reacted with human erythrocytes to form venom-sensitized erythrocytes. These cells were agglutinated specifically by high dilutions of adsorbed rabbit antivenin or were lysed by normal blood group compatible human sera. The specific rabbit antivenin prevented venom from attaching to erythrocytes, from interacting with serum complement, and from producing dermonecrotic lesions in rabbits. Results of experiments involving heat inactivation and adsorption to erythrocytes provide circumstantial evidence to suggest that the three biological activities of venom could be associated with a single component or few components with similar properties. The component interacting with serum complement is immunologically distinct from a factor in cobra venom which possesses similar biological activities.

  15. Light modulated activity of root alkaline/neutral invertase involves the interaction with 14-3-3 proteins.

    Science.gov (United States)

    Gao, Jing; van Kleeff, Paula J M; Oecking, Claudia; Li, Ka Wan; Erban, Alexander; Kopka, Joachim; Hincha, Dirk K; de Boer, Albertus H

    2014-12-01

    Alkaline/neutral invertases (A/N-Invs) are now recognized as essential proteins in plant life. They catalyze the irreversible breakdown of sucrose into glucose and fructose and thus supply the cells with energy as well as signaling molecules. In this study we report on a mechanism that affects the activity of the cytosolic invertase AtCINV1 (At-A/N-InvG or AT1G35580). We demonstrate that Ser547 at the extreme C-terminus of the AtCINV1 protein is a substrate of calcium-dependent kinases (CPK3 and 21) and that phosphorylation creates a high-affinity binding site for 14-3-3 proteins. The invertase as such has basal activity, but we provide evidence that interaction with 14-3-3 proteins enhances its activity. The analysis of three quadruple 14-3-3 mutants generated from six T-DNA insertion mutants of the non-epsilon family shows both specificity as well as redundancy for this function of 14-3-3 proteins. The strong reduction in hexose levels in the roots of one 14-3-3 quadruple mutant plant is in line with the activating function of 14-3-3 proteins. The physiological relevance of this mechanism that affects A/N-invertase activity is underscored by the light-induced activation and is another example of the central role of 14-3-3 proteins in mediating dark/light signaling. The nature of the light-induced signal that travels from the shoot to root and the question whether this signal is transmitted via cytosolic Ca(++) changes that activate calcium-dependent kinases, await further study. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  16. Geology of epithermal silver-gold bulk-mining targets, bodie district, Mono County, California

    Science.gov (United States)

    Hollister, V.F.; Silberman, M.L.

    1995-01-01

    The Bodie mining district in Mono County, California, is zoned with a core polymetallic-quartz vein system and silver- and gold-bearing quartz-adularia veins north and south of the core. The veins formed as a result of repeated normal faulting during doming shortly after extrusion of felsic flows and tuffs, and the magmatic-hydrothermal event seems to span at least 2 Ma. Epithermal mineralization accompanied repeated movement of the normal faults, resulting in vein development in the planes of the faults. The veins occur in a very large area of argillic alteration. Individual mineralized structures commonly formed new fracture planes during separate fault movements, with resulting broad zones of veinlets growing in the walls of the major vein-faults. The veinlet swarms have been found to constitute a target estimated at 75,000,000 tons, averaging 0.037 ounce gold per ton. The target is amenable to bulkmining exploitation. The epithermal mineralogy is simple, with electrum being the most important precious metal mineral. The host veins are typical low-sulfide banded epithermal quartz and adularia structures that filled voids created by the faulting. Historical data show that beneficiation of the simple vein mineralogy is very efficient. ?? 1995 Oxford University Press.

  17. Textural Evidence of Episodic Introduction of Metallic Nanoparticles into Bonanza Epithermal Ores

    Directory of Open Access Journals (Sweden)

    James A. Saunders

    2012-08-01

    Full Text Available Tertiary low sulfidation (LS epithermal deposits in the western USA often show evidence of the former presence of nanoparticle-sized precious-metal and silica phases in the highest grade (bonanza ores. Here, nanoparticles are defined to have a size less than ~10−7 m. The ore-mineral textures that formed from aggregation of nanoparticles (or colloids observed to date in these ores include electrum and naumannite (Ag2Se. Here it is proposed that chalcopyrite also forms nanoparticles in these ores, but sulfide nanoparticles apparently have significantly different physical (surface properties than the precious-metal phases, and thus exhibit different mineral textures (e.g., no textural evidence of previous chalcopyrite nanoparticles. Textures described here show that nanoparticles of precious-metal phases and silica were episodically and often repeatedly deposited to form the banded bonanza veins typical of many western USA epithermal deposits. Chalcopyrite is the most abundant metal-sulfide mineral in these bonanza ores, and it was also deposited episodically as well, and it appears to replace earlier formed naumannite dendrites. However, this apparent “replacement” texture may just be the result of naumannite dendrite limbs trapping chalcopyrite nanoparticles that later recrystallized to the apparent replacement texture. The episodic and repetitive nature of the metal-depositing events may record periodic “degassing” of magma chambers at depth, where metals are repeatedly delivered to the shallow epithermal environment by “vapor-phase” metal (loid transport.

  18. On the {sup 252}Cf primary and secondary gamma rays and epithermal neutron flux for BNCT

    Energy Technology Data Exchange (ETDEWEB)

    Ghassoun, J. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco)], E-mail: ghassoun@ucam.ac.ma; Merzouki, A. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco); Remote Sensing and Geomatics of the Environnement Laboratory, Ottawa-Carleton Geoscience Centre, Marion Hall-140Louis Pasteur Ottawa, ON, KIN 6N5 (Canada); El Morabiti, A.; Jehouani, A. [LPTN, Departement de Physique, Faculte des Sciences Semlalia, BP 2390, 40000 Marrakech (Morocco)

    2007-10-15

    Monte Carlo simulation has been used to calculate the different components of neutrons and secondary gamma rays originated by {sup 252}Cf fission and also the primary gamma rays emitted directly by the {sup 252}Cf source at the exit face of a compact system designed for the BNCT. The system consists of a {sup 252}Cf source and a moderator/reflector/filter assembly. To study the material properties and configuration possibilities, the MCNP code has been used. The moderator/reflector/filter arrangement is optimised to moderate neutrons to epithermal energy and, as far as possible, to get rid of fast and thermal neutrons and photons from the therapeutic beam. To reduce the total gamma contamination and to have a sufficiently high epithermal neutron flux we have used different photon filters of different thickness. Our analysis showed that the use of an appropriate filter leads to a gamma ray flux reduction without affecting the epithermal neutron beam quality at the exit face of the system.

  19. An accelerator-based epithermal photoneutron source for boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Hannah E. [Georgia Inst. of Technology, Atlanta, GA (United States)

    1996-04-01

    Boron neutron capture therapy is an experimental binary cancer radiotherapy modality in which a boronated pharmaceutical that preferentially accumulates in malignant tissue is first administered, followed by exposing the tissue in the treatment volume to a thermal neutron field. Current usable beams are reactor-based but a viable alternative is the production of an epithermal neutron beam from an accelerator. Current literature cites various proposed accelerator-based designs, most of which are based on proton beams with beryllium or lithium targets. This dissertation examines the efficacy of a novel approach to BNCT treatments that incorporates an electron linear accelerator in the production of a photoneutron source. This source may help to resolve some of the present concerns associated with accelerator sources, including that of target cooling. The photoneutron production process is discussed as a possible alternate source of neutrons for eventual BNCT treatments for cancer. A conceptual design to produce epithermal photoneutrons by high photons (due to bremsstrahlung) impinging on deuterium targets is presented along with computational and experimental neutron production data. A clinically acceptable filtered epithermal neutron flux on the order of 107 neutrons per second per milliampere of electron current is shown to be obtainable. Additionally, the neutron beam is modified and characterized for BNCT applications by employing two unique moderating materials (an Al/AlF3 composite and a stacked Al/Teflon design) at various incident electron energies.

  20. Synthesis, structural characterisation and antibacterial activity of Ag{sup +}-doped fluorapatite nanomaterials prepared by neutralization method

    Energy Technology Data Exchange (ETDEWEB)

    Stanić, Vojislav, E-mail: voyo@vinca.rs [University of Belgrade, Vinča Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia); Radosavljević-Mihajlović, Ana S. [University of Belgrade, Vinča Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia); Živković-Radovanović, Vukosava [University of Belgrade, Faculty of Chemistry, P.O. Box 51, 11158 Belgrade (Serbia); Nastasijević, Branislav; Marinović-Cincović, Milena; Marković, Jelena P.; Budimir, Milica D. [University of Belgrade, Vinča Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia)

    2015-05-15

    Graphical abstract: - Highlights: • The neutralization method has been used for synthesis of silver-doped fluorapatite powders. • Particles of silver-doped fluorapatite samples are of nano size and homogenous in composition. • The Ag{sup +}-doped fluorapatite samples showed antibacterial effect against Kllebsiela pneumoniae, Staphylococcus aureus and Micrococcus luteus. • AFM studies showed that silver-doped sample causes considerable morphological changes of tested bacterial cells. - Abstract: Silver doped fluorapatite nanopowders were synthesised by neutralization method, which consists of dissolving Ag{sub 2}O in solution of HF and H{sub 3}PO{sub 4} and addition to suspension of Ca(OH){sub 2}. The powder XRD, SEM and FTIR studies indicated the formation of a fluorapatite nanomaterials with average length of the particles is about 80 nm and a width of about 15 nm. The FTIR studies show that carbonate content in samples is very small and carbonte ions substitute both phosphate and hydroxyl groups in the crystal structure of samples, forming AB-type fluorapatite. Antibacterial studies have demonstrated that all Ag{sup +}-doped fluorapatite samples exhibit bactericidal effect against pathogens: Staphylococcus aureus, Micrococcus luteus and Kllebsiela pneumoniae. Antibacterial activity increased with the increase of Ag{sup +} in the samples. The atomic force microscopy studies revealed extensive damage to the bacterial cell envelops in the presence of Ag{sup +}-doped fluorapatite particles which may lead to their death. The synthesized Ag{sup +}-doped fluorapatite nanomaterials are promising as antibacterial biomaterials in orthopedics and dentistry.

  1. Analysis of Non-Enzymatically Glycated Peptides: Neutral-Loss Triggered MS3 Versus Multi-Stage Activation Tandem Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qibin; Petyuk, Vladislav A.; Schepmoes, Athena A.; Orton, Daniel J.; Monroe, Matthew E.; Yang, Feng; Smith, Richard D.; Metz, Thomas O.

    2008-10-15

    Non-enzymatic glycation of tissue proteins has important implications in the development of complications of diabetes mellitus. While electron transfer dissociation (ETD) has been shown to outperform collision-induced dissociation (CID) in sequencing glycated peptides by tandem mass spectrometry, ETD instrumentation is not yet available in all laboratories. In this study, we evaluated different advanced CID techniques (i.e., neutral-loss triggered MS3 and multi-stage activation) during LC-MSn analyses of Amadori-modified peptides enriched from human serum glycated in vitro. During neutral-loss triggered MS3 experiments, MS3 scans triggered by neutral-losses of 3 H2O or 3 H2O + HCHO produced similar results in terms of glycated peptide identifications. However, neutral losses of 3 H2O resulted in significantly more glycated peptide identifications during multi-stage activation experiments. Overall, the multi-stage activation approach produced more glycated peptide identifications, while the neutral-loss triggered MS3 approach resulted in much higher specificity. Both techniques offer a viable alternative to ETD for identifying glycated peptides when that method is unavailable.

  2. The first human epitope map of the alphaviral E1 and E2 proteins reveals a new E2 epitope with significant virus neutralizing activity.

    Directory of Open Access Journals (Sweden)

    Ann R Hunt

    2010-07-01

    Full Text Available Venezuelan equine encephalitis virus (VEEV is responsible for VEE epidemics that occur in South and Central America and the U.S. The VEEV envelope contains two glycoproteins E1 (mediates cell membrane fusion and E2 (binds receptor and elicits virus neutralizing antibodies. Previously we constructed E1 and E2 epitope maps using murine monoclonal antibodies (mMAbs. Six E2 epitopes (E2(c,d,e,f,g,h bound VEEV-neutralizing antibody and mapped to amino acids (aa 182-207. Nothing is known about the human antibody repertoire to VEEV or epitopes that engage human virus-neutralizing antibodies. There is no specific treatment for VEE; however virus-neutralizing mMAbs are potent protective and therapeutic agents for mice challenged with VEEV by either peripheral or aerosol routes. Therefore, fully human MAbs (hMAbs with virus-neutralizing activity should be useful for prevention or clinical treatment of human VEE.We used phage-display to isolate VEEV-specific hFabs from human bone marrow donors. These hFabs were characterized by sequencing, specificity testing, VEEV subtype cross-reactivity using indirect ELISA, and in vitro virus neutralization capacity. One E2-specific neutralizing hFAb, F5n, was converted into IgG, and its binding site was identified using competitive ELISA with mMAbs and by preparing and sequencing antibody neutralization-escape variants.Using 11 VEEV-reactive hFabs we constructed the first human epitope map for the alphaviral surface proteins E1 and E2. We identified an important neutralization-associated epitope unique to the human immune response, E2 aa115-119. Using a 9 A resolution cryo-electron microscopy map of the Sindbis virus E2 protein, we showed the probable surface location of this human VEEV epitope.The VEEV-neutralizing capacity of the hMAb F5 nIgG is similar to that exhibited by the humanized mMAb Hy4 IgG. The Hy4 IgG has been shown to limit VEEV infection in mice both prophylactically and therapeutically. Administration

  3. Mass Spectrometric Collisional Activation and Product Ion Mobility of Human Serum Neutral Lipid Extracts.

    Science.gov (United States)

    Hankin, Joseph A; Barkley, Robert M; Zemski-Berry, Karin; Deng, Yiming; Murphy, Robert C

    2016-06-21

    A novel method for lipid analysis called CTS (collisional activation and traveling wave mass spectrometry), involving tandem mass spectrometry of all precursor ions with ion mobility determinations of all product ions, was applied to a sample of human serum. The resulting four-dimensional data set (precursor ion, product ion, ion mobility value, and intensity) was found to be useful for characterization of lipids as classes as well as for identification of specific species. Utilization of ion mobility measurements of the product ions is a novel approach for lipid analysis. The trends and patterns of product mobility values when visually displayed yield information on lipid classes and specific species independent of mass determination. Collection of a comprehensive set of data that incorporates all precursor-product relationships, combined with ion mobility measurements of all products, enables data analysis where different molecular properties can be juxtaposed and analyzed to assist with class and species identification. Overall, CTS is a powerful, specific, and comprehensive method for lipid analysis.

  4. The neuromuscular activity of Micrurus pyrrhocryptus venom and its neutralization by commercial and specific coral snake antivenoms.

    Science.gov (United States)

    Camargo, Thiago Magalhães; de Roodt, Adolfo Rafael; da Cruz-Höfling, Maria Alice; Rodrigues-Simioni, Léa

    2011-01-01

    The neuromuscular activity ofMicrurus pyrrochryptus venom was studied in chick biventer cervicis (BC) and mouse phrenic nerve-diaphragm (PND) preparations. The venom (0.5-50μg/ml) caused irreversible, time- and concentration-dependent blockade, with BC being more sensitive than PND (50% blockade with 10μg/ml in 22±;3min and 62±4min, respectively; mean±SEM, n=6; p<0.05). In BC preparations, venom (0.5μg/ml) progressively abolished ACh-induced contractures, whereas contractures to exogenous KCl and muscle twitches in curarized preparations were unaffected. The venom neither altered creatine kinase release (venom: 25.8±1.75IU/l vs control: 24.3±2.2IU/l, n=6, after 120min), nor it caused significant muscle damage (50μg of venom/ml vs control: 3.5±0.8% vs 1.1±0.7% for PND; 4.3±1.5% vs 1.2±0.5% for BC, n=5). The venom had low PLA(2) activity. Neurotoxicity was effectively neutralized by commercial Micrurus antivenom and specific antivenom. These findings indicate that M. pyrrhocryptus venom acts postsynaptically on nicotinic receptors, with no significant myotoxicity.

  5. A study of the electrochemical activity of some macrolide antibiotics on a gold electrode in a neutral electrolyte

    Directory of Open Access Journals (Sweden)

    M. L. AVRAMOV IVIC

    2007-12-01

    Full Text Available The aim of the present study is to present the different reactivity of azithromycin and clarithromycin (pure and commercial at a gold electrode in neutral electrolyte using cyclic linear sweep voltammetry under the same experimental conditions. A gold electrode was successfully used for the electrochemical qualitative and quantitative determination of azithromycin dihydrate and azithromycin from capsules (Hemomycin® and for the separation of azithromycin from one of the excipients, lactose monohydrate. The good catalytically activity of the gold electrode was employed only for the qualitative electrochemical determination of pure clarithromycin by appearance of one cathodic and four anodic reactions, which enabled structural changes in this molecule during electrochemical reactions to be studied. Commercial clarithromycin, Clathrocyn® was qualitative determined by one reproducible anodic reaction. The activity of one of the excipients, Avicel, observed as a cathodic peak at different potential from the cathodic peak obtained with pure clarithromicin was used for the determination of its presence in Clathrocyn® tablets. FTIR Analysis showed the apparent changes in structure of pure clarithromycin, as well as in the molecule of clarithromycin in Clathrocyn® tablets. HPLC Analysis showed a significant decrease in the concentration of azithromycin, Hemomycin® clarithromycin and Clathrocyn® after the electrochemical reactions.

  6. Bench-scale study of active mine water treatment using cement kiln dust (CKD) as a neutralization agent.

    Science.gov (United States)

    Mackie, Allison L; Walsh, Margaret E

    2012-02-01

    The overall objective of this study was to investigate the potential impact on settled water quality of using cement kiln dust (CKD), a waste by-product, to replace quicklime in the active treatment of acidic mine water. Bench-scale experiments were conducted to evaluate the treatment performance of calcium hydroxide (Ca(OH)(2)) slurries generated using four different CKD samples compared to a control treatment with quicklime (CaO) in terms of reducing acidity and metals concentrations in acid mine drainage (AMD) samples taken from the effluent of a lead/zinc mine in Atlantic Canada. Results of the study showed that all of the CKD samples evaluated were capable of achieving greater than 97% removal of total zinc and iron. The amount of solid alkaline material required to achieve pH targets required for neutralization of the AMD was found to be higher for treatment with the CKD slurries compared to the quicklime slurry control experiments, and varied linearly with the free lime content of the CKD. The results of this study also showed that a potential benefit of treating mine water with CKD could be reduced settled sludge volumes generated in the active treatment process, and further research into the characteristics of the sludge generated from the use of CKD-generated calcium hydroxide slurries is recommended. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Ethylene C-H Bond Activation by Neutral Mn2O5 Clusters under Visible Light Irradiation.

    Science.gov (United States)

    Yin, Shi; Bernstein, Elliot R

    2016-05-05

    A photo excitation fast flow reactor coupled with a single-photon ionization (118 nm, 10.5 eV) time-of-flight mass spectrometry (TOFMS) instrument is used to investigate reactions of neutral MnmOn clusters with C2H4 under visible (532 nm) light irradiation. Association products Mn2O5(C2H4) and Mn3O6,7(C2H4) are observed without irradiation. Under light irradiation, the Mn2O5(C2H4) TOFMS feature decreases, and a new species, Mn2O5H2, is observed. This light-activated reaction suggests that the visible radiation can induce the chemistry, Mn2O5 + C2H4 + hv(532 nm) → Mn2O5*(C2H4) → Mn2O5H2 + C2H2. High barriers (0.67 and 0.59 eV) are obtained on the ground-state potential energy surface (PES); the reaction is barrierless and thermodynamically favorable on the first excited-state PES, as performed by time-dependent density functional theory calculations. The calculational and experimental results suggest that Mn2O5-like structures on manganese oxide surfaces are the appropriate active catalytic sites for visible light photocatalysis of ethylene dehydrogenation.

  8. Activation and deactivation of neutral palladium(II) phosphinesulfonato polymerization catalysts

    KAUST Repository

    Rünzi, Thomas

    2012-12-10

    13C-Labeled ethylene polymerization (pre)catalysts [κ2-(anisyl)2P,O]Pd(13CH3)(L) (1-13CH3-L) (L = pyridine, dmso) based on di(2-anisyl)phosphine benzenesulfonate were used to assess the degree of incorporation of 13CH3 groups into the formed polyethylenes. Polymerizations of variable reaction time reveal that ca. 60-85% of the 13C-label is found in the polymer after already 1 min polymerization time, which provides evidence that the pre-equilibration between the catalyst precursor 1-13CH3-L and the active species 1-13CH3-(ethylene) is fast with respect to chain growth. The fraction of 1-13CH3-L that initiates chain growth is likely higher than the 60-85% determined from the 13C-labeled polymer chain ends since (a) chain walking results in in-chain incorporation of the 13C-label, (b) irreversible catalyst deactivation by formation of saturated (and partially volatile) alkanes diminishes the amount of 13CH3 groups incorporated into the polymer, and (c) palladium-bound 13CH3 groups, and more general palladium-bound alkyl(polymeryl) chains, partially transfer to phosphorus by reductive elimination. NMR and ESI-MS analyses of thermolysis reactions of 1-13CH3-L provide evidence that a mixture of phosphonium salts (13CH3)xP+(aryl)4-x (2-7) is formed in the absence of ethylene. In addition, isolation and characterization of the mixed bis(chelate) palladium complex [κ2-(anisyl)2P,O]Pd[κ2-(anisyl) (13CH3)P,O] (11) by NMR and X-ray diffraction analyses from these mixtures indicate that oxidative addition of phosphonium salts to palladium(0) species is also operative. The scrambling of palladium-bound carbyls and phosphorus-bound aryls is also relevant under NMR, as well as preparative reactor polymerization conditions exemplified by the X-ray diffraction analysis of [κ2-(anisyl)2P,O] Pd[κ2-(anisyl)(CH2CH3)P,O] (12) and [κ2-(anisyl)2P,O]Pd[κ2-(anisyl) ((CH2)3CH3)P,O] (13) isolated from pressure reactor polymerization experiments. In addition, ESI-MS analyses of reactor

  9. Magmatism and Epithermal Gold-Silver Deposits of the Southern Ancestral Cascade Arc, Western Nevada and Eastern California

    Science.gov (United States)

    John, David A.; du Bray, Edward A.; Henry, Christopher D.; Vikre, Peter

    2015-01-01

    Many epithermal gold-silver deposits are temporally and spatially associated with late Oligocene to Pliocene magmatism of the southern ancestral Cascade arc in western Nevada and eastern California. These deposits, which include both quartz-adularia (low- and intermediate-sulfidation; Comstock Lode, Tonopah, Bodie) and quartz-alunite (high-sulfidation; Goldfield, Paradise Peak) types, were major producers of gold and silver. Ancestral Cascade arc magmatism preceded that of the modern High Cascades arc and reflects subduction of the Farallon plate beneath North America. Ancestral arc magmatism began about 45 Ma, continued until about 3 Ma, and extended from near the Canada-United States border in Washington southward to about 250 km southeast of Reno, Nevada. The ancestral arc was split into northern and southern segments across an inferred tear in the subducting slab between Mount Shasta and Lassen Peak in northern California. The southern segment extends between 42°N in northern California and 37°N in western Nevada and was active from about 30 to 3 Ma. It is bounded on the east by the northeast edge of the Walker Lane. Ancestral arc volcanism represents an abrupt change in composition and style of magmatism relative to that in central Nevada. Large volume, caldera-forming, silicic ignimbrites associated with the 37 to 19 Ma ignimbrite flareup are dominant in central Nevada, whereas volcanic centers of the ancestral arc in western Nevada consist of andesitic stratovolcanoes and dacitic to rhyolitic lava domes that mostly formed between 25 and 4 Ma. Both ancestral arc and ignimbrite flareup magmatism resulted from rollback of the shallowly dipping slab that began about 45 Ma in northeast Nevada and migrated south-southwest with time. Most southern segment ancestral arc rocks have oxidized, high potassium, calc-alkaline compositions with silica contents ranging continuously from about 55 to 77 wt%. Most lavas are porphyritic and contain coarse plagioclase

  10. Transintestinal Cholesterol Transport Is Active in Mice and Humans and Controls Ezetimibe-Induced Fecal Neutral Sterol Excretion.

    Science.gov (United States)

    Jakulj, Lily; van Dijk, Theo H; de Boer, Jan Freark; Kootte, Ruud S; Schonewille, Marleen; Paalvast, Yared; Boer, Theo; Bloks, Vincent W; Boverhof, Renze; Nieuwdorp, Max; Beuers, Ulrich H W; Stroes, Erik S G; Groen, Albert K

    2016-12-13

    Except for conversion to bile salts, there is no major cholesterol degradation pathway in mammals. Efficient excretion from the body is therefore a crucial element in cholesterol homeostasis. Yet, the existence and importance of cholesterol degradation pathways in humans is a matter of debate. We quantified cholesterol fluxes in 15 male volunteers using a cholesterol balance approach. Ten participants repeated the protocol after 4 weeks of treatment with ezetimibe, an inhibitor of intestinal and biliary cholesterol absorption. Under basal conditions, about 65% of daily fecal neutral sterol excretion was bile derived, with the remainder being contributed by direct transintestinal cholesterol excretion (TICE). Surprisingly, ezetimibe induced a 4-fold increase in cholesterol elimination via TICE. Mouse studies revealed that most of ezetimibe-induced TICE flux is mediated by the cholesterol transporter Abcg5/Abcg8. In conclusion, TICE is active in humans and may serve as a novel target to stimulate cholesterol elimination in patients at risk for cardiovascular disease. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Development of IgY antibodies against anti-snake toxins endowed with highly lethal neutralizing activity.

    Science.gov (United States)

    da Rocha, David Gitirana; Fernandez, Jorge Hernandez; de Almeida, Cláudia Maria Costa; da Silva, Cláudia Letícia; Magnoli, Fábio Carlos; da Silva, Osmair Élder; da Silva, Wilmar Dias

    2017-08-30

    Snakebite envenoming is a major neglected disease related to poverty in developing countries. Treatment involves the administration of a specific antivenom serum and auxiliary therapies, if necessary. The improvement of antibodies is of great importance for the technological advancement of antivenom therapy and to reduce the morbidity and mortality associated with this medical burden. In the present study, adult hens were immunized nine times with 20μg of B. arietans or C. d. terrificus venoms at three-week intervals between immunizations. Developing antibodies presented increasing avidity and affinity to antigenic toxin epitopes along immunization, attaining a plateau after the seventh immunization. Pooled egg yolk-purified IgY antivenom antibodies, subjected to in vitro-in vivo lethality assay using Swiss adult mice, exhibited potent venom lethal neutralizing activity. Taken together, chickens under the described immunization schedule were considered alternative candidates for antivenom production. Lower maintenance costs, a simple antibody manufacturing process and immunization suffering restrictions are additional advantages. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Learning the Relationship between the Primary Structure of HIV Envelope Glycoproteins and Neutralization Activity of Particular Antibodies by Using Artificial Neural Networks

    Science.gov (United States)

    Buiu, Cătălin; Putz, Mihai V.; Avram, Speranta

    2016-01-01

    The dependency between the primary structure of HIV envelope glycoproteins (ENV) and the neutralization data for given antibodies is very complicated and depends on a large number of factors, such as the binding affinity of a given antibody for a given ENV protein, and the intrinsic infection kinetics of the viral strain. This paper presents a first approach to learning these dependencies using an artificial feedforward neural network which is trained to learn from experimental data. The results presented here demonstrate that the trained neural network is able to generalize on new viral strains and to predict reliable values of neutralizing activities of given antibodies against HIV-1. PMID:27727189

  13. Neutralizing activities of human immunoglobulin derived from donors in Japan against mosquito-borne flaviviruses, Japanese encephalitis virus, West Nile virus, and dengue virus

    Directory of Open Access Journals (Sweden)

    Yunoki M

    2016-07-01

    Full Text Available Mikihiro Yunoki,1-3 Takeshi Kurosu,2 Ritsuko Kubota Koketsu,2,4 Kazuo Takahashi,5 Yoshinobu Okuno,4 Kazuyoshi Ikuta2,4 1Research and Development Division, Japan Blood Products Organization, Tokyo, 2Department of Virology, Research Institute for Microbial Diseases, Osaka University, Osaka, 3Pathogenic Risk Evaluation, Graduate School of Veterinary Medicine, Rakuno Gakuen University, Hokkaido, 4Research and Development Division, The Research Foundation for Microbial Diseases of Osaka University, Kagawa, 5Osaka Prefectural Institute of Public Health, Osaka, Japan Abstract: Japanese encephalitis virus (JEV, West Nile virus (WNV, and dengue virus (DenV are causal agents of Japanese encephalitis, West Nile fever, and dengue fever, respectively. JEV is considered to be indigenized and widespread in Japan, whereas WNV and DenV are not indigenized in Japan. Globulin products seem to reflect the status of the donor population according to antivirus neutralization activity. However, the anti-JEV, -WNV, and -DenV neutralization activities of globulin products derived from donors in Japan have not been clarified. Furthermore, potential candidates for the development of an effective immunotherapeutic drug for encephalitis caused by JEV, WNV, or DenV have also not been identified. Therefore, the aim of this study was to determine the overall status of the donor population in Japan based on globulin products by evaluating anti-JEV, -WNV, and -DenV neutralizing activities of intravenous immunoglobulin. Overall, intravenous immunoglobulin products showed stable neutralizing activity against JEV but showed no or only weak activity against WNV or DenV. These results suggest that the epidemiological level against WNV and DenV in the donor population of Japan is still low, suggesting that these viruses are not yet indigenized. In addition, JEV vaccinations and/or infections in the donor population do not induce a cross-reactive antibody against WNV. Keywords

  14. Isotype modulates epitope specificity, affinity, and antiviral activities of anti-HIV-1 human broadly neutralizing 2F5 antibody.

    Science.gov (United States)

    Tudor, Daniela; Yu, Huifeng; Maupetit, Julien; Drillet, Anne-Sophie; Bouceba, Tahar; Schwartz-Cornil, Isabelle; Lopalco, Lucia; Tuffery, Pierre; Bomsel, Morgane

    2012-07-31

    The constant heavy chain (CH1) domain affects antibody affinity and fine specificity, challenging the paradigm that only variable regions contribute to antigen binding. To investigate the role of the CH1 domain, we constructed IgA2 from the broadly neutralizing anti-HIV-1 2F5 IgG1, and compared 2F5 IgA2 and IgG binding affinity and functional activities. We found that 2F5 IgA2 bound to the gp41 membrane proximal external region with higher affinity than IgG1. Functionally, compared with IgG1, 2F5 IgA2 more efficiently blocked HIV-1 transcytosis across epithelial cells and CD4(+) cell infection by R5 HIV-1. The 2F5 IgG1 and IgA2 acted synergistically to fully block HIV-1 transfer from Langerhans to autologous CD4(+) T cells and to inhibit CD4(+) T-cell infection. Epitope mapping performed by screening a random peptide library and in silico docking modeling suggested that along with the 2F5 IgG canonical ELDKWA epitope on gp41, the IgG1 recognized an additional 3D-conformational epitope on the gp41 C-helix. In contrast, the IgA2 epitope included a unique conformational motif on the gp41 N-helix. Overall, the CH1 region of 2F5 contributes to shape its epitope specificity, antibody affinity, and functional activities. In the context of sexually transmitted infections such as HIV-1/AIDS, raising a mucosal IgA-based vaccine response should complement an IgG-based vaccine response in blocking HIV-1 transmission.

  15. Isotype modulates epitope specificity, affinity, and antiviral activities of anti–HIV-1 human broadly neutralizing 2F5 antibody

    Science.gov (United States)

    Tudor, Daniela; Yu, Huifeng; Maupetit, Julien; Drillet, Anne-Sophie; Bouceba, Tahar; Schwartz-Cornil, Isabelle; Lopalco, Lucia; Tuffery, Pierre; Bomsel, Morgane

    2012-01-01

    The constant heavy chain (CH1) domain affects antibody affinity and fine specificity, challenging the paradigm that only variable regions contribute to antigen binding. To investigate the role of the CH1 domain, we constructed IgA2 from the broadly neutralizing anti–HIV-1 2F5 IgG1, and compared 2F5 IgA2 and IgG binding affinity and functional activities. We found that 2F5 IgA2 bound to the gp41 membrane proximal external region with higher affinity than IgG1. Functionally, compared with IgG1, 2F5 IgA2 more efficiently blocked HIV-1 transcytosis across epithelial cells and CD4+ cell infection by R5 HIV-1. The 2F5 IgG1 and IgA2 acted synergistically to fully block HIV-1 transfer from Langerhans to autologous CD4+ T cells and to inhibit CD4+ T-cell infection. Epitope mapping performed by screening a random peptide library and in silico docking modeling suggested that along with the 2F5 IgG canonical ELDKWA epitope on gp41, the IgG1 recognized an additional 3D-conformational epitope on the gp41 C-helix. In contrast, the IgA2 epitope included a unique conformational motif on the gp41 N-helix. Overall, the CH1 region of 2F5 contributes to shape its epitope specificity, antibody affinity, and functional activities. In the context of sexually transmitted infections such as HIV-1/AIDS, raising a mucosal IgA-based vaccine response should complement an IgG-based vaccine response in blocking HIV-1 transmission. PMID:22723360

  16. Metrology and quality of radiation therapy dosimetry of electron, photon and epithermal neutron beams

    Science.gov (United States)

    Kosunen, Antti

    In radiation therapy using electron and photon beams the dosimetry chain consists of several sequential phases starting by the realization of the dose quantity in the Primary Standard Dosimetry Laboratory and ending to the calculation of the dose to a patient. A similar procedure can be described for the dosimetry of epithermal neutron beams in boron neutron capture therapy (BNCT). This work is focused on two items in the dosimetry chains: the determination of the dose in the reference conditions and the evaluation of the accuracy of dose calculation methods. The issues investigated and discussed in detail are: (a)the calibration methods of plane parallel ionization chambers used in electron beam dosimetry, (b)the specification of the critical dosimetric parameter i.e. the ratio of stopping powers for water to air, (S/r) waterair , in photon beams, (c)the feasibility of the twin ionization chamber technique for dosimetry in epithermal neutron beams applied to BNCT and (d)the determination accuracy of the calculated dose distributions in phantoms in electron, photon, and epithermal neutron beams. The results demonstrate that UP to a 3% improvement in the consistency of dose determinations in electron beams is achieved by the calibration of plane parallel ionization chambers in high energy electron beams instead of calibrations in 60Co gamma beams. In photon beam dosimetry (S/r) waterair can be determined with an accuracy of 0.2% using the percentage dose at the 10 cm depth, %dd(10), as a beam specifier. By a twin ionization chamber technique accuracy the gamma dose can be determined with uncertainty of 6% (1 standard deviation) and the total neutron dose with an uncertainty of 15 to 20% (1 standard deviation). The general accuracy achieved by treatment planning systems is approximately 4% for photons and 5 to 7% for electrons. Large (>10%) deviations in calculated doses are possible even when relatively modern calculation approaches are used.

  17. Correlation of Lunar South Polar Epithermal Neutron Maps: Lunar Exploration Neutron Detector and Lunar Prospector Neutron Detector

    Science.gov (United States)

    McClanahan, Timothy P.; Mitrofanov, I. G.; Boynton, W. V.; Sagdeev, R.; Trombka, J. I.; Starr, R. D.; Evans, L. G.; Litvak, M. L.; Chin, G.; Garvin, J.; hide

    2010-01-01

    The Lunar Reconnaissance Orbiter's (LRO), Lunar Exploration Neutron Detector (LEND) was developed to refine the lunar surface hydrogen (H) measurements generated by the Lunar Prospector Neutron Spectrometer. LPNS measurements indicated a approx.4,6% decrease in polar epithermal fluxes equivalent to (1.5+/-0,8)% H concentration and are direct geochemical evidence indicating water /high H at the poles. Given the similar operational and instrumental objectives of the LEND and LPNS systems, an important science analysis step for LEND is to test correlation with existing research including LPNS measurements. In this analysis, we compare corrected low altitude epithermal rate data from LPNS available via NASA's Planetary Data System (PDS) with calibrated LEND epithermal maps using a cross-correlation technique

  18. Metrology and quality of radiation therapy dosimetry of electron, photon and epithermal neutron beams

    Energy Technology Data Exchange (ETDEWEB)

    Kosunen, A

    1999-08-01

    In radiation therapy using electron and photon beams the dosimetry chain consists of several sequential phases starting by the realisation of the dose quantity in the Primary Standard Dosimetry Laboratory and ending to the calculation of the dose to a patient. A similar procedure can be described for the dosimetry of epithermal neutron beams in boron neutron capture therapy (BNCT). To achieve the required accuracy of the dose delivered to a patient the quality of all steps in the dosimetry procedure has to be considered. This work is focused on two items in the dosimetry chains: the determination of the dose in the reference conditions and the evaluation of the accuracy of dose calculation methods. The issues investigated and discussed in detail are: a)the calibration methods of plane parallel ionisation chambers used in electron beam dosimetry, (b) the specification of the critical dosimetric parameter i.e. the ratio of stopping powers for water to air, (S I ?){sup water} {sub air}, in photon beams, (c) the feasibility of the twin ionization chamber technique for dosimetry in epithermal neutron beams applied to BNCT and (d) the determination accuracy of the calculated dose distributions in phantoms in electron, photon, and epithermal neutron beams. The results demonstrate that up to a 3% improvement in the consistency of dose determinations in electron beams is achieved by the calibration of plane parallel ionisation chambers in high energy electron beams instead of calibrations in {sup 60}Co gamma beams. In photon beam dosimetry (S I ?){sup water} {sub air} can be determined with an accuracy of 0.2% using the percentage dose at the 10 cm depth, %dd(10), as a beam specifier. The use of %odd(10) requires the elimination of the electron contamination in the photon beam. By a twin ionisation chamber technique the gamma dose can be determined with uncertainty of 6% (1 standard deviation) and the total neutron dose with an uncertainty of 15 to 20% (1 standard deviation

  19. Generation and characterization of tabalumab, a human monoclonal antibody that neutralizes both soluble and membrane-bound B-cell activating factor

    Directory of Open Access Journals (Sweden)

    Manetta J

    2014-08-01

    Full Text Available Joseph Manetta, Holly Bina, Paul Ryan, Niles Fox, Derrick R Witcher, Kristine Kikly Biotechnology Discovery Research, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USA Abstract: B-cell activating factor (BAFF is a B-cell survival factor with a key role in B-cell homeostasis and tolerance. Dysregulated BAFF expression may contribute to autoimmune diseases or B-cell malignancies via effects on abnormal B-lymphocyte activation, proliferation, survival, and immunoglobulin secretion. Monoclonal antibodies were generated against human BAFF, characterized for species specificity and affinity, and screened for the ability to neutralize both membrane-bound and soluble BAFF. In addition, studies were undertaken to determine the relative potency of membrane-bound and soluble BAFF. Tabalumab has a high affinity for human, cynomolgus monkey, and rabbit BAFF. No binding to mouse BAFF was detected. Tabalumab was able to neutralize soluble human, cynomolgus monkey, or rabbit BAFF with equal potency. Our data demonstrate that membrane-bound BAFF can be a more potent stimulus for B-cells than soluble BAFF, and tabalumab also neutralized membrane-bound BAFF. Tabalumab prevented BAFF from binding to BAFF receptors and demonstrated pharmacodynamic effects in human BAFF transgenic mice. Tabalumab is a high-affinity human antibody with neutralizing activity against membrane-bound and soluble BAFF. Given our findings that membrane-bound BAFF can have greater in vitro potency than soluble BAFF, neutralization of both forms of BAFF is likely to be important for optimal therapeutic effect. Keywords: autoimmunity, B-cell malignancies, B-cell survival factor, BAFF

  20. Are You Neutral About Net Neutrality

    Science.gov (United States)

    2007-06-20

    Information Resources Management College National Defense University Are You Neutral About Net Neutrality ? A presentation for Systems & Software...author uses Verizon FiOS for phone, TV, and internet service 3 Agenda Net Neutrality —Through 2 Lenses Who Are the Players & What Are They Saying...Medical Treatment Mini-Case Studies Updates Closing Thoughts 4 Working Definitions of Net Neutrality "Network Neutrality" is the concept that

  1. Molecular dynamics simulation of the effect of hydrophobic cosolutes on the neutral hydrolysis of an activated ester

    NARCIS (Netherlands)

    Rispens, Theo; Lensink, MF; Berendsen, HJC; Engberts, JBFN

    2004-01-01

    We have studied, by means of molecular dynamics (MD) simulations, the effect of two hydrophobic cosolutes, tert-butanol (t-BuOH) and ethanol (EtOH), on the neutral hydrolysis of p-methoxyphenyl dichloroacetate (MPDA) in water. Shifts were calculated in a pre-equilibrium, defined as a spatial

  2. Development of novel LL-37 derived antimicrobial peptides with LPS and LTA neutralizing and antimicrobial activities for therapeutic application.

    NARCIS (Netherlands)

    Nell, M.J.; Tjabringa, G.S.; Wafelman, A.R.; Verrijk, R.; Hiemstra, P.S.; Drijfhout, J.W.; Grote, J.J.

    2006-01-01

    New peptides for lipopolysaccharide (LPS) and lipoteichoic acid (LTA) neutralization in upper respiratory tract infections were developed and evaluated in terms of efficacy and safety for application in humans. Based on the sequence of the human antimicrobial peptide LL-37 we developed and

  3. ACDOS1: a computer code to calculate dose rates from neutron activation of neutral beamlines and other fusion-reactor components

    Energy Technology Data Exchange (ETDEWEB)

    Keney, G.S.

    1981-08-01

    A computer code has been written to calculate neutron induced activation of neutral-beam injector components and the corresponding dose rates as a function of geometry, component composition, and time after shutdown. The code, ACDOS1, was written in FORTRAN IV to calculate both activity and dose rates for up to 30 target nuclides and 50 neutron groups. Sufficient versatility has also been incorporated into the code to make it applicable to a variety of general activation problems due to neutrons of energy less than 20 MeV.

  4. Gold grade distribution within an epithermal quartz vein system, Kestanelik, NW Turkey: implications for gold exploration

    Science.gov (United States)

    Gulyuz, Nilay; Shipton, Zoe; Gulyuz, Erhan; Lord, Richard; Kaymakci, Nuretdin; Kuscu, İlkay

    2017-04-01

    Vein-hosted gold deposits contribute a large part to the global gold production. Discovery of these deposits mainly include drilling of hundreds of holes, collecting thousands of soil and rock samples and some geophysical surveys which are expensive and time consuming. Understanding the structures hosting the veins and the variations in gold concentrations within the veins is crucial to constrain a more economic exploration program. The main aim of this study is to investigate the gold grade distribution in the mineralized quartz veins of a well exposed epithermal gold deposit hosted by Paleozoic schist and Eocene quartz-feldspar-hornblende porphyry in Lapseki, NW Turkey. We have constructed 3D architecture of the vein surfaces by mapping their outcrop geometries using a highly sensitive Trimble GPS, collecting detailed field data, well-logs and geochemistry data from 396 drill holes (255 diamond cut and 141 reverse circulation holes). Modelling was performed in MOVE Structural Modelling and Analysis software granted by Midland Valley's Academic Software Initiative, and GIS application softwares Global Mapper and Esri-ArcGIS. We envisaged that while fluid entering the conduit ascents, a sudden thickness increase in the conduit would lead to a drop in the fluid pressure causing boiling (the most dominant gold precipitation mechanism) and associated gold precipitation. Regression analysis was performed between the orthogonal thickness values and gold grades of each vein, and statistical analyses were performed to see if the gold is concentrated at specific structural positions along dip. Gold grades in the alteration zones were compared to those in the adjacent veins to understand the degree of mineralization in alteration zones. A possible correlation was also examined between the host rock type and the gold grades in the veins. These studies indicated that gold grades are elevated in the adjacent alteration zones where high gold grades exist in the veins. Schist

  5. Use of a synthetic biosensor for neutralizing activity-biased selection of monoclonal antibodies against atroxlysin-I, an hemorrhagic metalloproteinase from Bothrops atrox snake venom.

    Directory of Open Access Journals (Sweden)

    Francisco Santos Schneider

    2014-04-01

    Full Text Available BACKGROUND: The snake Bothrops atrox is responsible for the majority of envenomings in the northern region of South America. Severe local effects, including hemorrhage, which are mainly caused by snake venom metalloproteinases (SVMPs, are not fully neutralized by conventional serum therapy. Little is known about the immunochemistry of the P-I SVMPs since few monoclonal antibodies (mAbs against these molecules have been obtained. In addition, producing toxin-neutralizing mAbs remains very challenging. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report on the set-up of a functional screening based on a synthetic peptide used as a biosensor to select neutralizing mAbs against SVMPs and the successful production of neutralizing mAbs against Atroxlysin-I (Atr-I, a P-I SVMP from B. atrox. Hybridomas producing supernatants with inhibitory effect against the proteolytic activity of Atr-I towards the FRET peptide Abz-LVEALYQ-EDDnp were selected. Six IgG1 Mabs were obtained (named mAbatr1 to mAbatr6 and also two IgM. mAbatrs1, 2, 3 and 6 were purified. All showed a high specific reactivity, recognizing only Atr-I and B. atrox venom in ELISA and a high affinity, showing equilibrium constants in the nM range for Atr-I. These mAbatrs were not able to bind to Atr-I overlapping peptides, suggesting that they recognize conformational epitopes. CONCLUSIONS/SIGNIFICANCE: For the first time a functional screening based on a synthetic biosensor was successfully used for the selection of neutralizing mAbs against SVMPs.

  6. Epithermal uranium deposits in a volcanogenic context: the example of Nopal 1 deposit, Sierra de Pena Blanca, Mexico

    Science.gov (United States)

    Calas, G.; Angiboust, S.; Fayek, M.; Camacho, A.; Allard, T.; Agrinier, P.

    2009-12-01

    The Peña Blanca molybdenum-uranium field (Chihuahua, Mexico) exhibits over 100 airborne anomalies hosted in tertiary ignimbritic ash-flow tuffs (44 Ma) overlying the Pozos conglomerate and a sequence of Cretaceous carbonate rocks. Uranium occurrences are associated with breccia zones at the intersection of two or more fault systems. Periodic reactivation of these structures associated with Basin and Range and Rio Grande tectonic events resulted in the mobilization of U and other elements by meteoric fluids heated by geothermal activity. Trace element geochemistry (U, Th, REE) provides evidence for local mobilization of uranium under oxidizing conditions. In addition, O- and H-isotope geochemistry of kaolinite, smectite, opal and calcite suggests that argillic alteration proceeded at shallow depth with meteoric water at 25-75 °C. Focussed along breccia zones, fluids precipitated several generations of pyrite and uraninite together with kaolinite, as in the Nopal 1 mine, indicating that mineralization and hydrothermal alteration of volcanic tuffs are contemporaneous. Low δ34S values (~ -24.5 ‰) of pyrites intimately associated with uraninite suggest that the reducing conditions at the origin of the U-mineralization arise from biological activity. Later, the uplift of Sierra Pena Blanca resulted in oxidation and remobilization of uranium, as confirmed by the spatial distribution of radiation-induced defect centers in kaolinites. These data show that tectonism and biogenic reducing conditions can play a major role in the formation and remobilization of uranium in epithermal deposits. By comparison with the other uranium deposits at Sierra Pena Blanca and nearby Sierra de Gomez, Nopal 1 deposit is one of the few deposits having retained a reduced uranium mineralization.

  7. Search for active neutrino disappearance using neutral-current interactions in the MINOS long-baseline experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; /Fermilab; Andreopoulos, C.; /Rutherford; Arms, Kregg E.; /Minnesota U.; Armstrong, R.; /Indiana U.; Auty, D.J.; /Sussex U.; Ayres, D.S.; /Argonne; Backhouse, C. /Oxford U.; Baller, B.; /Fermilab; Barr, G.; /Oxford U.; Barrett, W.L.; /Western Washington U.; Becker, B.R.; /Minnesota U. /Rutherford

    2008-07-01

    We have measured the rates and spectra of neutral-current neutrino interactions in the MINOS detectors, which are separated by 734 km. A depletion in the rate at the far site would indicate mixing between {nu}{sub {mu}} and a sterile particle. The depletion of the total neutral-current event rate at the far site is limited to be below 17% at 90% confidence level without {nu}{sub e} appearance. Assuming oscillations occur at a single mass-squared splitting, a fit to the neutral- and charged-current energy spectra shows the fraction of {nu}{sub {mu}} oscillating to a sterile neutrino is 0.28{sub -0.28}{sup +0.25}(stat.+syst.). Including {nu}{sub e} appearance at the current experimental upper bound limits the depletion to be below 21% at 90% confidence level and the fit fraction of {nu}{sub {mu}} oscillating to a sterile neutrino is 0.43{sub -0.27}{sup +0.23}(stat.+syst.).

  8. Amygdala Activation During Emotion Processing of Neutral Faces in Children With Severe Mood Dysregulation Versus ADHD or Bipolar Disorder

    Science.gov (United States)

    Brotman, Melissa A.; Rich, Brendan A.; Guyer, Amanda E.; Lunsford, Jessica R.; Horsey, Sarah E.; Reising, Michelle M.; Thomas, Laura A.; Fromm, Stephen J.; Towbin, Kenneth; Pine, Daniel S.; Leibenluft, Ellen

    2010-01-01

    Objective To understand disorder-unique and common pathophysiology, studies in multiple patient groups with overlapping symptoms are needed. Deficits in emotion processing and hyperarousal symptoms are prominent features of bipolar disorder, attention deficit hyperactivity disorder (ADHD), and severe mood dysregulation. The authors compared amygdala response during emotional and nonemotional ratings of neutral faces in youths with these disorders as well as a group of healthy comparison youths. Method Blood-oxygen-level-dependent (BOLD) signal in the amygdala was examined in children with bipolar disorder (N=43), ADHD (N=18), and severe mood dysregulation (N=29) and healthy comparison subjects (N=37). During functional magnetic resonance imaging (fMRI), participants attended to emotional and nonemotional aspects of neutral faces. Results While rating subjective fear of neutral faces, youths with ADHD demonstrated left amygdala hyperactivity relative to the other three groups, whereas youths with severe mood dysregulation demonstrated hypoactivity. Conclusions These findings support the role of unique neural correlates in face-emotion processing among youths with bipolar disorder, ADHD, and severe mood dysregulation. PMID:19917597

  9. Double C-H bond activation of hydrocarbons by a gas phase neutral oxide cluster: the importance of spin state.

    Science.gov (United States)

    Wang, Zhe-Chen; Yin, Shi; Bernstein, Elliot R

    2013-03-21

    The neutral cluster V2O5 is generated and detected in the gas phase. Its reactivity toward butane is studied both experimentally and theoretically. Experimental results show clearly that neutral V2O5 can react with n-butane (C4H10) to generate V2O5H2, indicating double hydrogen atom transfer from C4H10 to V2O5 to produce C4H8. Further experimental evidence indicates that V2O5 is only partially reacted even at very high concentrations of C4H10. Density functional theory (DFT) studies show that the lowest energy triplet state of V2O5 is reactive toward C4H10, whereas the ground state singlet V2O5 is inert. Calculated results are in agreement with experimental findings, and a detailed reaction mechanism is provided. Reactions of V2O5H2 with several oxidants are also studied theoretically to find a path to regenerate V2O5. Neutral (3)V2O5 can also react with C2H6 to form V2O5H2 and C2H4, but only as a minor reaction channel; the major product is the adsorption product V2O5(C2H6).

  10. A novel bifunctional protein TNFR2-Fc-IL-1ra (TFI): expression, purification and its neutralization activity of inflammatory factors.

    Science.gov (United States)

    Xie, Bo; Liu, Shan; Wu, Shuyin; Chang, Alan; Jin, Weiyuan; Guo, Zhixiang; Ye, Shuaidong; Hui, Mizhou

    2013-06-01

    Tumor necrosis factor receptor (TNF) and internleukin-1 (IL-1) are the most potent proinflammatory cytokines involving in autoimmune and inflammatory human diseases. Many anti-inflammatory agents have been exploited for anti-inflammation treatments by targeting cytokines including TNF and IL-1. Theoretically, simultaneously neutralizing or blocking two important inflammatory mediators may achieve a synergistic therapeutic effect. We have developed a recombinant fusion protein, TNFR2-Fc-IL-1ra (TFI), which consists of a TNF-neutralizing domain that specifically binds to TNF-α, an IL-1 receptor antagonist domain, and a dimerization Fc portion of human IgG1, for bifunctional inflammatory inhibitor. Recombinant DNA expressing the sequence of this fusion protein was expressed in CHO-S cells. The protein product was purified using a two-step purification protocol and the identity of the protein was confirmed by western blot analysis. The purified recombinant protein had a purity of about 98 % as determined by HPLC, and a molecular mass of 164.6 kDa as determined by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. The results of cell binding inhibition indicate that TFI was able to strongly neutralize TNF activity and antagonize IL-1r activity, suggesting that TFI may be used as a bifunctional ligand with enhanced anti-inflammatory effect. The result obtained in this study may provide a platform for extending bifunctional anti-inflammatory drug development.

  11. Modeling thermospheric neutral density

    Science.gov (United States)

    Qian, Liying

    Satellite drag prediction requires determination of thermospheric neutral density. The NCAR Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIEGCM) and the global-mean Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model (TIMEGCM) were used to quantify thermospheric neutral density and its variations, focusing on annual/semiannual variation, the effect of using measured solar irradiance on model calculations of solar-cycle variation, and global change in the thermosphere. Satellite drag data and the MSIS00 empirical model were utilized to compare to the TIEGCM simulations. The TIEGCM simulations indicated that eddy diffusion and its annual/semiannual variation is a mechanism for annual/semiannual density variation in the thermosphere. It was found that eddy diffusion near the turbopause can effectively influence thermospheric neutral density. Eddy diffusion, together with annual insolation variation and large-scale circulation, generated global annual/semiannual density variation observed by satellite drag. Using measured solar irradiance as solar input for the TIEGCM improved the solar-cycle dependency of the density calculation shown in F10.7 -based thermospheric empirical models. It has been found that the empirical models overestimate density at low solar activity. The TIEGCM simulations did not show such solar-cycle dependency. Using historic measurements of CO2 and F 10.7, simulations of the global-mean TIMEGCM showed that thermospheric neutral density at 400 km had an average long-term decrease of 1.7% per decade from 1970 to 2000. A forecast of density decrease for solar cycle 24 suggested that thermospheric density will decrease at 400 km from present to the end of solar cycle 24 at a rate of 2.7% per decade. Reduction in thermospheric density causes less atmospheric drag on earth-orbiting space objects. The implication of this long-term decrease of thermospheric neutral density is that it will increase the

  12. Optimization study for an epithermal neutron beam for boron neutron capture therapy at the University of Virginia Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Jr., Thomas Dean [Univ. of Virginia, Charlottesville, VA (United States)

    1995-05-01

    The non-surgical brain cancer treatment modality, Boron Neutron Capture Therapy (BNCT), requires the use of an epithermal neutron beam. This purpose of this thesis was to design an epithermal neutron beam at the University of Virginia Research Reactor (UVAR) suitable for BNCT applications. A suitable epithermal neutron beam for BNCT must have minimal fast neutron and gamma radiation contamination, and yet retain an appreciable intensity. The low power of the UVAR core makes reaching a balance between beam quality and intensity a very challenging design endeavor. The MCNP monte carlo neutron transport code was used to develop an equivalent core radiation source, and to perform the subsequent neutron transport calculations necessary for beam model analysis and development. The code accuracy was validated by benchmarking output against experimental criticality measurements. An epithermal beam was designed for the UVAR, with performance characteristics comparable to beams at facilities with cores of higher power. The epithermal neutron intensity of this beam is 2.2 x 108 n/cm2 • s. The fast neutron and gamma radiation KERMA factors are 10 x 10-11cGy•cm2/nepi and 20 x 10-11 cGy•cm2/nepi , respectively, and the current-to-flux ratio is 0.85. This thesis has shown that the UVAR has the capability to provide BNCT treatments, however the performance characteristics of the final beam of this study were limited by the low core power.

  13. New Insight into the Hydrogen Evolution Reaction under Buffered Near-Neutral pH Conditions: Enthalpy and Entropy of Activation

    KAUST Repository

    Shinagawa, Tatsuya

    2016-10-06

    Electrochemical conversion of thermodynamically stable chemicals of water and carbon dioxide is regarded as a core technology for achieving sustainability in our society. In both cases, the electrochemical hydrogen evolution reaction (HER) is a key reaction, particularly at near-neutral pH. This study addresses the kinetic aspects of the HER in buffered near-neutral pH conditions using a variety of electrode materials (W, Ni, Pt, Au, and Cu) over a wide temperature range (299–346 K). When the overall performance was summarized with respect to the binding energy of the reaction intermediate species, a classic volcano-shaped relationship was obtained. Interestingly, the temperature sensitivity analysis disclosed that smaller activation energies did not always lead to higher performance in 1.5 mol L–1 K-phosphate solution (pH 5.8). Detailed analysis of the temperature- and potential-dependent parameters revealed that smaller activation energies coincided with smaller values of the pre-exponential factor in the Arrhenius’ equation (associated with the entropy of activation). Due to the trade-off relationship of enthalpy–entropy compensation in the current system, the conventional approach of mixing elements of lower and higher binding energies to the intermediate species failed: even though Ni–Cu showed lower apparent activation energy, its activity toward the HER was between that of Ni and Cu due to the lowered entropy of activation. This study demonstrates the unrevealed fundamental aspects of the HER in buffered near-neutral condition, which contributes to the rational development of efficient energy and material conversion systems.

  14. In vitro genotoxicity of neutral red after photo-activation and metabolic activation in the Ames test, the micronucleus test and the comet assay.

    Science.gov (United States)

    Guérard, Melanie; Zeller, Andreas; Singer, Thomas; Gocke, Elmar

    2012-07-04

    Neutral red (Nr) is relatively non-toxic and is widely used as indicator dye in many biological test systems. It absorbs visible light and is known to act as a photosensitizer, involving the generation of reactive oxygen species (type-I reaction) and singlet oxygen (type-II reaction). The mutagenicity of Nr was determined in the Ames test (with Salmonella typhimurium strains TA1535, TA97, TA98, TA98NR, TA100, and TA102) with and without metabolic activation, and with and without photo-activation on agar plates. Similarly to the situation following metabolic activation, photo-mutagenicity of Nr was seen with all Salmonella strains tested, albeit with different effects between these strains. To our knowledge, Nr is the only photo-mutagen showing such a broad action. Since the effects are also observed in strains not known to be responsive to ROS, this indicates that ROS production is not the sole mode of action that leads to photo-genotoxicity. The reactive species produced by irradiation are short-lived as pre-irradiation of an Nr solution did not produce mutagenic effects when added to the bacteria. In addition, mutagenicity in TA98 following irradiation was stronger than in the nitroreductase-deficient strain TA98NR, indicating that nitro derivatives that are transformed by bacterial nitroreductase to hydroxylamines appear to play a role in the photo-mutagenicity of Nr. Photo-genotoxicity of Nr was further investigated in the comet assay and micronucleus test in L5178Y cells. Concentration-dependent increases in primary DNA damage and in the frequency of micronuclei were observed after irradiation. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Epithermal Neutron Observations and Lunar South Pole Targeting for LCROSS Impact Planning using the Lunar Reconnaissance Orbiter (LRO), Lunar Exploring Neutron Detector (LEND)

    Science.gov (United States)

    McClanahan, T. P.; Mitrofanov, I.; Boynton, W. V.; Chin, G.; Colaprete, A.; Evans, L. G.; Garvin, J.; Harshman, K.; Litvak, R.; Malakhov, A.; hide

    2009-01-01

    LCROSS impact targeting and planning efforts included quantifying South Polar epithermal neutron flux depressions in early LEND mapped results to maximize the expected plume Hydrogen (H) yield. Epithermal neutron surface fluxes are a key geochemical indicator of surface Hydrogen (H) concentration inferred to be elevated in polar permanent shadow regions (PSR). LCROSS impact target regions were delineated as (PSR) using illumination modeling of polar topography. To quantify targets potential yield for LCROSS, LEND epithermal neutron flux observations were integrated over LCROSS targets of interest and compared to background observations. Discussion will define methods review impact prior estimates and contrast post impact results.

  16. The Bi'r Tawilah deposit, central western Saudi Arabia: Supergene enrichment of a Pan-African epithermal gold mineralization

    Science.gov (United States)

    Surour, Adel A.; Harbi, Hesham M.; Ahmed, Ahmed H.

    2014-01-01

    The Bi'r Tawilah gold deposit in central western Saudi Arabia represents a Pan-African example of gold mineralization in which both hypogene and supergene ores are recorded. The sulphidic gold ore is hosted in intermediate to felsic intrusions that occur along the N-S trending thrust-fault zone within the so-called “Nabitah orogenic zone”. There are four rock units present (from oldest to youngest): serpentinites and related listwaenites, diorites, granitic rocks and porphyries. Hydrothermal alteration consists of chloritization, sericitization, carbonatization and silicification and affects all rock types. Chloritization of biotite results in abundant rutile, whereas sulphidization coincides with carbonatization. The Bi'r Tawilah ore is confined to NW-trending shears (Riedel fractures) related to N-S slip of the pre-existing Tawilah thrust due to activation within the Najd fault system. Samples from the boreholes show macro- and microscopic evidence of shearing such as micro-shear planes and strain shadows of pyrite. Sulphides and gold are present in most rock types. Paragenetically, the sulphides consist of abundant pyrite and relatively lesser amounts of arsenopyrite, in addition to very minor chalcopyrite, sphalerite and galena. In all boreholes, it was noticed that the abundance of arsenopyrite increases with depth. The elevated silver content of electrum (∼13-22 wt%) at Bi'r Tawilah is typical of gold deposits and low-sulphidation epithermal deposits. The early mineralization stage took place in proximity to hydrothermally altered intermediate to felsic intrusions. The aerially restricted hydrothermal alteration by carbon-aqueous fluids led to ore remobilization in which gold amounts up to 4.3 g/t. Finally, gold enrichment (up to 5.4 g/t) resulted from supergene alteration that took place during weathering above the water table at a depth of ∼20-25 m.

  17. Zoning in the Carboniferous-Lower Permian Cracow epithermal vein system, central Queensland, Australia

    Science.gov (United States)

    Dong, G. Y.; Zhou, T.

    1996-03-01

    Four epithermal vein deposits (i.e. Dawn, Central Extended, Rose’s Pride and Klondyke) in the Cracow gold field, central Queensland were investigated in terms of paragenesis, mineralogy, vein textures, fluid inclusions and stable isotopes. The Cracow epithermal field is confined to an area approximately 6 by 5 kilometers. All the deposits are hosted by the massive Camboon Andesite of Upper Carboniferous to Lower Permian age, occur as open-space vein fillings, and have similar paragenesis. However, significant variations in mineralogy, textures of quartz and adularia, and fluid geochemistry were found for a main mineralisation stage (Stage II) of each individual deposits. At Rose’s Pride and Klondyke, base-metal sulphides are virtually absent, but significant amounts of calcite and quartz with minor adularia are widely distributed. Replacement textures are distinct, and mineralisation temperature is less than 220 °C and salinity less than 0.2 wt%. The δ18O values of quartz and calcite range from -2.65 to -2.06‰ and from -6.66 to -6.34‰ respectively, and calculated δ18OH2O value is about -17‰ which represents a nearly unshifted palaeo-meteoric water. Gold mineralisation is best developed at Central Extended among the studied deposits, where patches rich in electrum are often observed in polished thin sections and where gold grades exceeding 10 g/t are frequently indicated by assays. Base-metal sulphides are only present locally and rarely exceed 5 volume percent of the vein samples. Quartz is the dominant gangue mineral, but significant amounts of rhombic adularia and chlorite are widely distributed. Various primary and recrystallisation textures possibly inherited from silica gel are well developed and widespread. At individual sites where crustiform bands developed from both walls of a fissure, temperatures could drop sharply from 275 °C to less than 220 °C. The ore-forming fluid at Central Extended, compared with that at Rose’s Pride and Klondyke

  18. Effective dose evaluation for BNCT treatment in the epithermal neutron beam at THOR

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.N. [Department of Engineering and System Science, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan (China)] [Division of Health Physics, Institute of Nuclear Energy Research, No. 1000, Wenhua Rd., Jiaan Village, Longtan Township, Taoyuan County 32546, Taiwan (China); Huang, C.K. [Institute of Nuclear Engineering and Science, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan (China); Tsai, W.C. [Department of Engineering and System Science, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan (China); Liu, Y.H. [Nuclear Science and Technol. Develop. Center, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan (China); Jiang, S.H., E-mail: shjiang@mx.nthu.edu.tw [Department of Engineering and System Science, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan (China)] [Institute of Nuclear Engineering and Science, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Rd., Hsinchu 30013, Taiwan (China)

    2011-12-15

    This paper aims to evaluate the effective dose as well as equivalent doses of several organs of an adult hermaphrodite mathematical phantom according to the definition of ICRP Publication 60 for BNCT treatments of brain tumors in the epithermal neutron beam at THOR. The MCNP5 Monte Carlo code was used for the calculation of the average absorbed dose of each organ. The effective doses for a typical brain tumor treatment with a tumor treatment dose of 20 Gy-eq were evaluated to be 0.59 and 0.35 Sv for the LLAT and TOP irradiation geometries, respectively. In addition to the stochastic effect, it was found that it is also likely to produce deterministic effects, such as cataracts and depression of haematopoiesis.

  19. Neutralization of toxicological activities of medically-relevant Bothrops snake venoms and relevant toxins by two polyvalent bothropic antivenoms produced in Peru and Brazil.

    Science.gov (United States)

    Estevao-Costa, Maria I; Gontijo, Silea S; Correia, Barbara L; Yarleque, Armando; Vivas-Ruiz, Dan; Rodrigues, Edith; Chávez-Olortegui, Carlos; Oliveira, Luciana S; Sanchez, Eladio F

    2016-11-01

    Snakebite envenoming is a neglected public pathology, affecting especially rural communities or isolated areas of tropical and subtropical Latin American countries. The parenteral administration of antivenom is the mainstay and the only validated treatment of snake bite envenoming. Here, we assess the efficacy of polyspecific anti-Bothrops serum (α-BS) produced in the Instituto Nacional de Salud (INS, Peru) and at the Fundação Ezequiel Dias (FUNED, Brazil), to neutralize the main toxic activities induced by five medically-relevant venoms of: Bothrops atrox, B. barnetti, and B. pictus from Peru, and the Brazilian B. jararaca and B. leucurus, all of them inhabiting different geographical locations. Protein electrophoretic patterns of these venoms showed significant differences in composition, number and intensity of bands. Another goal was to evaluate the efficacy and safety of lyophilized α-BS developed at INS to neutralize the detrimental effects of these venoms using in vivo and in vitro assays. The availability of lyophilized α-BS has relevant significance in its distribution to distant rural communities where the access to antivenom in health facilities is more difficult. Despite the fact that different antigen mixtures were used for immunization during antivenom production, our data showed high toxin-neutralizing activity of α-BS raised against Bothrops venoms. Moreover, the antivenom cross-reacted even against venoms not included in the immunization mixture. Furthermore, we have evaluated the efficacy of both α-BS to neutralize key toxic compounds belonging to the predominant protein families of Bothrops snakes. Most significantly, both α-BS cross-specifically neutralized the main toxicological activities e.g. lethality and hemorrhage induced by these venoms. Thus, our data indicate that both α-BS are equally effective to treat snake bite victims inflicted by Bothrops snakes particularly B. atrox, responsible for the largest numbers of human

  20. Geochemistry and statistical analyses of porphyry system and epithermal veins at Hizehjan in northwestern Iran

    Science.gov (United States)

    Radmard, Kaikhosrov; Zamanian, Hassan; Hosseinzadeh, Mohamad Reza; Khalaji, Ahmad Ahmadi

    2017-12-01

    Situated about 130 km northeast of Tabriz (northwest Iran), the Mazra'eh Shadi deposit is in the Arasbaran metallogenic belt (AAB). Intrusion of subvolcanic rocks, such as quartz monzodiorite-diorite porphyry, into Eocene volcanic and volcano-sedimentary units led to mineralisation and alteration. Mineralisation can be subdivided into a porphyry system and Au-bearing quartz veins within andesite and trachyandesite which is controlled by fault distribution. Rock samples from quartz veins show maximum values of Au (17100 ppb), Pb (21100 ppm), Ag (9.43ppm), Cu (611ppm) and Zn (333 ppm). Au is strongly correlated with Ag, Zn and Pb. In the Au-bearing quartz veins, factor group 1 indicates a strong correlation between Au, Pb, Ag, Zn and W. Factor group 2 indicates a correlation between Cu, Te, Sb and Zn, while factor group 3 comprises Mo and As. Based on Spearman correlation coefficients, Sb and Te can be very good indicator minerals for Au, Ag and Pb epithermal mineralisation in the study area. The zoning pattern shows clearly that base metals, such as Cu, Pb, Zn and Mo, occur at the deepest levels, whereas Au and Ag are found at higher elevations than base metals in boreholes in northern Mazra'eh Shadi. This observation contrasts with the typical zoning pattern caused by boiling in epithermal veins. At Mazra'eh Shadi, quartz veins containing co-existing liquid-rich and vapour-rich inclusions, as strong evidence of boiling during hydrothermal evolution, have relatively high Au grades (up to 813 ppb). In the quartz veins, Au is strongly correlated with Ag, and these elements are in the same group with Fe and S. Mineralisation of Au and Ag is a result of pyrite precipitation, boiling of hydrothermal fluids and a pH decrease.

  1. Antibodies to human IL-10 neutralize ebvIL-10-mediated cytokine suppression but have no effect on cmvIL-10 activity.

    Science.gov (United States)

    Brodeur, Noelle D; Spencer, Juliet V

    2010-11-01

    Interleukin-10 is a pivotal determinant of virus clearance or persistence. Two human herpesviruses, Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) are unique among persistent viruses because they not only trigger production of host IL-10, but both viruses also encode homologs of IL-10 that are expressed during infection. Because anti-human IL-10 antibodies have diagnostic value and therapeutic potential for many chronic infections, cross-reactivity with ebvIL-10 and cmvIL-10 was evaluated in this study. Six of seven anti-hIL-10 antibodies tested recognized ebvIL-10 and neutralized its immunosuppressive activity. In contrast, cmvIL-10 was neither recognized nor neutralized by any anti-human IL-10 antibody. These findings demonstrate that IL-10-neutralizing treatments in HCMV- or EBV-infected patients may require consideration of the contribution of viral IL-10 to disease pathology. Copyright © 2010 Elsevier B.V. All rights reserved.

  2. The Stypsi-Megala Therma porphyry-epithermal mineralization, Lesvos Island, Greece: new mineralogical and geochemical data

    Science.gov (United States)

    Periferakis, Argyrios; Voudouris, Panagiotis; Melfos, Vasilios; Mavrogonatos, Constantinos; Alfieris, Dimitrios

    2017-04-01

    anomalies to those previously reported by [1] but also provide additional information in a series of elements: Cu (up to 843 ppm), Mo (up to 76 ppm), Au (up to 120 ppb), Pb (up to 339ppm), Zn (up to 815ppm), Se (up to 10ppm), Te (up to 4 ppm), Bi (up to 4 ppm) and Sn (up to 23 ppm). The Lesvos Island may be interpreted as the westward extension of the Eocene-Miocene Biga peninsula Cu-Au porphyry belt, with potential for future discoveries of Cu-Mo±Au deposits in the Aegean area. [1] Voudouris P, Alfieris D (2005) New porphyry-Cu±Mo occurrences in northeastern Aegean/Greece: Ore mineralogy and transition to epithermal environment. In: Mao J, Bierlein FP (eds) Mineral deposit research: Meeting the global challenge. Springer Verlag, 473-476; [2] Kontis E, Kelepertsis AE, Skounakis S (1994) Geochemistry and alteration facies associated with epithermal precious metal mineralization in an active geothermal system, northern Lesvos, Greece. Min Deposita, 29:430-433; [3] Muntean JL, Einaudi MT (2000) Porphyry Gold Deposits of the Refugio District, Maricunga Belt, Northern Chile. Econ. Geology, 95, 1445-1472.

  3. Electromyographic analysis of gluteus maximus and hamstring activity during the supine resisted hip extension exercise versus supine unilateral bridge to neutral.

    Science.gov (United States)

    Youdas, James W; Hartman, James P; Murphy, Brooke A; Rundle, Ashley M; Ugorowski, Jenna M; Hollman, John H

    2017-02-01

    Hip extension strengthening exercises which maximize gluteus maximus contributions and minimize hamstring influences may be beneficial for persons with hip pain. This study's aim was to compare muscle activation of the gluteus maximus and hamstrings from healthy subjects during a supine resisted hip extension exercise versus supine unilateral bridge to neutral. Surface electromyographic (EMG) signals were obtained from the right gluteus maximus and hamstrings in 13 healthy male and 13 healthy female subjects. Maximum voluntary isometric contractions (MVICs) were collected to normalize data and permit meaningful comparisons across muscles. Peak median activation of the gluteus maximus was 33.8% MVIC for the bridge and 34.7% MVIC for the hip extension exercise, whereas peak median recruitment for hamstrings was 28.4% MVIC for the bridge and 51% MVIC for the hip extension exercise. The gluteus maximus to hamstrings ratio was compared between the two exercises using the Wilcoxon signed-ranks test (α = 0.05). The ratio (p = 0.014) was greater in the supine unilateral bridge (median = 111.3%) than supine hip extension exercise (median = 59.2%), suggesting a reduction of hamstring recruitment in the unilateral bridge to neutral compared to the supine resisted hip extension exercise. The supine hip extension exercise demonstrated higher EMG activity of hamstrings in comparison with supine unilateral bridge and, therefore, may be less appropriate in subjects who need to increase gluteus maximus activation.

  4. 9G4 autoreactivity is increased in HIV-infected patients and correlates with HIV broadly neutralizing serum activity.

    Directory of Open Access Journals (Sweden)

    James J Kobie

    Full Text Available The induction of a broadly neutralizing antibody (BNAb response against HIV-1 would be a desirable feature of a protective vaccine. Vaccine strategies thus far have failed to elicit broadly neutralizing antibody responses; however a minority of HIV-infected patients do develop circulating BNAbs, from which several potent broadly neutralizing monoclonal antibodies (mAbs have been isolated. The findings that several BNmAbs exhibit autoreactivity and that autoreactive serum antibodies are observed in some HIV patients have advanced the possibility that enforcement of self-tolerance may contribute to the rarity of BNAbs. To examine the possible breakdown of tolerance in HIV patients, we utilized the 9G4 anti-idiotype antibody system, enabling resolution of both autoreactive VH4-34 gene-expressing B cells and serum antibodies. Compared with healthy controls, HIV patients had significantly elevated 9G4+ serum IgG antibody concentrations and frequencies of 9G4+ B cells, a finding characteristic of systemic lupus erythematosus (SLE patients, both of which positively correlated with HIV viral load. Compared to the global 9G4-IgD--memory B cell population, the 9G4+IgD--memory fraction in HIV patients was dominated by isotype switched IgG+ B cells, but had a more prominent bias toward "IgM only" memory. HIV envelope reactivity was observed both in the 9G4+ serum antibody and 9G4+ B cell population. 9G4+ IgG serum antibody levels positively correlated (r = 0.403, p = 0.0019 with the serum HIV BNAbs. Interestingly, other serum autoantibodies commonly found in SLE (anti-dsDNA, ANA, anti-CL did not correlate with serum HIV BNAbs. 9G4-associated autoreactivity is preferentially expanded in chronic HIV infection as compared to other SLE autoreactivities. Therefore, the 9G4 system provides an effective tool to examine autoreactivity in HIV patients. Our results suggest that the development of HIV BNAbs is not merely a consequence of a general breakdown in

  5. In vivo evaluation of the cross-genotype neutralizing activity of polyclonal antibodies against hepatitis C virus

    DEFF Research Database (Denmark)

    Meuleman, Philip; Bukh, Jens; Verhoye, Lieven

    2011-01-01

    , the outcome of a homologous challenge is highly influenced by the amount of challenge virus injected. Depending on the viral genotype used, H06-antibodies were able to protect up to 50% of chimeric mice from a heterologous challenge. Animals in which the antibody pretreatment failed displayed a clear delay......Control of hepatitis C virus (HCV) infection remains a huge challenge of global medical importance. Using a variety of in vitro approaches, neutralizing antibodies (nAbs) have been identified in patients with acute and chronic hepatitis C. The exact role these nAbs play in the resolution of acute...... genotypes (gt) in vivo. Following passive immunization with H06-antibodies, chimeric mice were challenged with the consensus strains H77C (gt1a), ED43 (gt4a), or HK6a (gt6a). In accordance with previous results, H06-antibodies prevented infection of chimeric mice with the autologous virus. However...

  6. Comparative study of the cytolytic activity of snake venoms from African spitting cobras (Naja spp., Elapidae) and its neutralization by a polyspecific antivenom.

    Science.gov (United States)

    Méndez, Ileana; Gutiérrez, José María; Angulo, Yamileth; Calvete, Juan J; Lomonte, Bruno

    2011-11-01

    Venoms of several Naja species found in Sub-Saharan Africa, and commonly known as "spitting cobras", induce a predominantly cytotoxic pattern of envenomings that may evolve into tissue necrosis and gangrene. Cytotoxic components of their venoms have been identified as members of the three-finger toxin and phospholipase A(2) protein families. In this study, an in vitro assay using the myogenic cell line C2C12, was utilized to compare the cytolytic activities of venoms from five species of spitting cobras: Naja nigricollis, Naja katiensis, Naja pallida, Naja nubiae, and Naja mossambica. These venoms were strongly cytotoxic, causing a 50% effect at ~1.5 μg/well (15 μg/ml), except for N. katiensis venom, which required nearly twice this amount. Using the cell-based assay, the ability of an equine polyspecific antivenom (EchiTab-Plus-ICP) to neutralize cytotoxicity was assessed. The antivenom completely inhibited the cytotoxic activity of all five venoms, although high antivenom/venom ratios were needed. Neutralization curves displayed the following decreasing order of efficiency: N. nubiae > N. pallida > N. mossambica > N. nigricollis > N. katiensis. Results indicate that neutralizing antibodies toward toxins responsible for this particular effect are present in the antivenom, albeit in low titers. Fucoidan, a natural sulfated polysaccharide known to inhibit the toxic effects of some basic snake venom components, was unable to reduce cytotoxicity of Naja venoms. Results emphasize the need of enhancing the immunogenicity of low molecular mass toxins during antivenom production, as well as to search for useful toxin inhibitors which could complement antivenom therapy. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Fluid inclusion chemistry of adularia-sericite epithermal Au-Ag deposits of the southern Hauraki Goldfield, New Zealand

    Science.gov (United States)

    Simpson, Mark P.; Strmic Palinkas, Sabina; Mauk, Jeffrey L.; Bodnar, Robert J.

    2015-01-01

    Microthermometry, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), and Raman spectroscopy have been used to determine the temperature, apparent salinity, and composition of individual fluid inclusions in adularia-sericite Au-Ag epithermal veins from the Karangahake, Martha, Favona, and Waitekauri deposits, southern Hauraki goldfield, New Zealand. Quartz veins contain colloform to crustiform bands that alternate with coarse-grained quartz and amethyst. The ore mineralization occurs only in colloform to crustiform bands.

  8. Hubungan Kondisi Geologi terhadap Alterasi dan Mineralisasi Endapan Epithermal Daerah Sualan, Kecamatan Talegong, Kabupaten Garut, Provinsi Jawa Barat

    OpenAIRE

    Kumala Sari, Paramitha Eka

    2013-01-01

    In exploration process of epithermal deposit, it is important to understand alteration and mineralization. The presence of alteration and mineralization zones help development of ore mineral exploration. Hydrothermal alteration is change of the chemistry, physics, mineralogy and origin textures of rocks as it interacts with the hydrothermal fluid. Alteration and mineralization zones has characteristics and certain minerals in each area.The research purposes are to determine the geological ...

  9. Characterization of an invertase with pH tolerance and truncation of its N-terminal to shift optimum activity toward neutral pH.

    Science.gov (United States)

    Du, Liqin; Pang, Hao; Wang, Zilong; Lu, Jian; Wei, Yutuo; Huang, Ribo

    2013-01-01

    Most invertases identified to date have optimal activity at acidic pH, and are intolerant to neutral or alkaline environments. Here, an acid invertase named uninv2 is described. Uninv2 contained 586 amino acids, with a 100 amino acids N-terminal domain, a catalytic domain and a C-terminal domain. With sucrose as the substrate, uninv2 activity was optimal at pH 4.5 and at 45°C. Removal of N-terminal domain of uninv2 has shifted the optimum pH to 6.0 while retaining its optimum temperaure at 45°C. Both uninv2 and the truncated enzyme retained highly stable at neutral pH at 37°C, and they were stable at their optimum pH at 4°C for as long as 30 days. These characteristics make them far superior to invertase from Saccharomyces cerevisiae, which is mostly used as industrial enzyme.

  10. Characterization of an invertase with pH tolerance and truncation of its N-terminal to shift optimum activity toward neutral pH.

    Directory of Open Access Journals (Sweden)

    Liqin Du

    Full Text Available Most invertases identified to date have optimal activity at acidic pH, and are intolerant to neutral or alkaline environments. Here, an acid invertase named uninv2 is described. Uninv2 contained 586 amino acids, with a 100 amino acids N-terminal domain, a catalytic domain and a C-terminal domain. With sucrose as the substrate, uninv2 activity was optimal at pH 4.5 and at 45°C. Removal of N-terminal domain of uninv2 has shifted the optimum pH to 6.0 while retaining its optimum temperaure at 45°C. Both uninv2 and the truncated enzyme retained highly stable at neutral pH at 37°C, and they were stable at their optimum pH at 4°C for as long as 30 days. These characteristics make them far superior to invertase from Saccharomyces cerevisiae, which is mostly used as industrial enzyme.

  11. Formation conditions of high-grade gold-silver ore of epithermal Tikhoe deposit, Russian Northeast

    Science.gov (United States)

    Volkov, A. V.; Kolova, E. E.; Savva, N. E.; Sidorov, A. A.; Prokof'ev, V. Yu.; Ali, A. A.

    2016-09-01

    The Tikhoe epithermal deposit is located in the Okhotsk-Chukotka volcanic belt (OChVB) 250 km northeast of Magadan. Like other deposits belonging to the Ivan'insky volcanic-plutonic depression (VTD), the Tikhoe deposit is characterized by high-grade Au-Ag ore with an average Au grade of 23.13 gpt Au and Au/Ag ratio varying from 1: 1 to 1: 10. The detailed explored Tikhoe-1 orebody is accompanied by a thick (20 m) aureole of argillic alteration. Pyrite is predominant among ore minerals; galena, arsenopyrite, sphalerite, Ag sulfosalts, fahlore, electrum, and küstelite are less abundant. The ore is characterized by abundant Sebearing minerals. Cu-As geochemical specialization is noted for silver minerals. Elevated Se and Fe molar fractions of the main ore minerals are caused by their formation in the near-surface argillic alteration zone. The veins and veinlets of the Tikhoe-1 ore zone formed stepwise at a temperature of 230 to 105°C from Nachloride solution enriched in Mg and Ca cations with increasing salinity. The parameters of the ore-forming fluid correspond to those of epithermal low-sulfidation deposits and assume the formation of high-grade ore under a screening unit of volcanic rocks. In general, the composition of the ore-forming fluid fits the mineralogy and geochemistry of ore at this deposit. The similarity of the ore composition and parameters of the ore-forming fluid between the Tikhoe and Julietta deposits is noteworthy. Meanwhile, differences are mainly related to the lower temperature and fluid salinity at the Julietta deposit with respect to the Tikhoe deposit. The fluid at the Julietta deposit is depleted in most components compared with that at the Tikhoe deposit except for Sb, Cd, and Ag. The results testify to a different erosion level at the deposits as derivatives of the same ore-forming system. The large scale of the latter allows us to predict the discovery of new high-grade objects, including hidden mineralization, which is not exposed at

  12. The alanine detector in BNCT dosimetry: Dose response in thermal and epithermal neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, T., E-mail: schmito@uni-mainz.de [Institute for nuclear chemistry, Johannes Gutenberg-University, Mainz D-55128 (Germany); Bassler, N. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus C, Aarhus 8000 (Denmark); Blaickner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220 (Austria); Ziegner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220, Austria and TU Wien, Vienna University of Technology, Vienna A-1020 (Austria); Hsiao, M. C. [Insitute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Liu, Y. H. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Koivunoro, H. [Department of Physics, University of Helsinki, POB 64, FI-00014, Finland and HUS Medical Imaging Center, Helsinki University Central Hospital, FI-00029 HUS (Finland); Auterinen, I.; Serén, T.; Kotiluoto, P. [VTT Technical Research Centre of Finland, Espoo (Finland); Palmans, H. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW, United Kingdom and Medical Physics Group, EBG MedAustron GmbH, Wiener Neustadt A-2700 (Austria); Sharpe, P. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW (United Kingdom); Langguth, P. [Department of Pharmacy and Toxicology, University of Mainz, Mainz D-55128 (Germany); Hampel, G. [Institut für Kernchemie, Johannes Gutenberg-Universität, Mainz D-55128 (Germany)

    2015-01-15

    Purpose: The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. Methods: Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a {sup 60}Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes FLUKA and MCNP. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen and Olsen alanine response model. Results: The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. Conclusions: The

  13. A yeast mitotic activator sensitises the shoot apical meristem to become floral in day-neutral tobacco.

    Science.gov (United States)

    Vojvodová, Petra; Mašková, Petra; Francis, Dennis; Lipavská, Helena

    2013-10-01

    True day-neutral (DN) plants flower regardless of day-length and yet they flower at characteristic stages. DN Nicotiana tabacum cv. Samsun, makes about forty nodes before flowering. The question still persists whether flowering starts because leaves become physiologically able to export sufficient floral stimulus or the shoot apical meristem (SAM) acquires developmental competence to interpret its arrival. This question was addressed using tobacco expressing the Schizosaccharomyces pombe cell cycle gene, Spcdc25, as a tool. Spcdc25 expression induces early flowering and we tested a hypothesis that this phenotype arises because of premature floral competence of the SAM. Scions of vegetative Spcdc25 plants were grafted onto stocks of vegetative WT together with converse grafts and flowering onset followed (as the time since sowing and number of leaves formed till flowering). Spcdc25 plants flowered significantly earlier with fewer leaves, and, unlike WT, also formed flowers from axillary buds. Scions from vegetative Spcdc25 plants also flowered precociously when grafted to vegetative WT stocks. However, in a WT scion to Spcdc25 stock, the plants flowered at the same time as WT. SAMs from young vegetative Spcdc25 plants were elongated (increase in SAM convexity determined by tracing a circumference of SAM sections) with a pronounced meristem surface cell layers compared with WT. Presumably, Spcdc25 SAMs were competent for flowering earlier than WT and responded to florigenic signal produced even in young vegetative WT plants. Precocious reproductive competence in Spcdc25 SAMs comprised a pronounced mantle, a trait of prefloral SAMs. Hence, we propose that true DN plants export florigenic signal since early developmental stages but the SAM has to acquire competence to respond to the floral stimulus.

  14. Neutral Buoyancy Laboratory (NBL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Neutral Buoyancy Laboratory (NBL) is an astronaut training facility and neutral buoyancy pool operated by NASA and located at the Sonny Carter Training Facility,...

  15. Improvement of activated carbons as oxygen reduction catalysts in neutral solutions by ammonia gas treatment and their performance in microbial fuel cells

    KAUST Repository

    Watson, Valerie J.

    2013-11-01

    Commercially available activated carbon (AC) powders from different precursor materials (peat, coconut shell, coal, and hardwood) were treated with ammonia gas at 700 C to improve their performance as oxygen reduction catalysts in neutral pH solutions used in microbial fuel cells (MFCs). The ammonia treated ACs exhibited better catalytic performance in rotating ring-disk electrode tests than their untreated precursors, with the bituminous based AC most improved, with an onset potential of Eonset = 0.12 V (untreated, Eonset = 0.08 V) and n = 3.9 electrons transferred in oxygen reduction (untreated, n = 3.6), and the hardwood based AC (treated, E onset = 0.03 V, n = 3.3; untreated, Eonset = -0.04 V, n = 3.0). Ammonia treatment decreased oxygen content by 29-58%, increased nitrogen content to 1.8 atomic %, and increased the basicity of the bituminous, peat, and hardwood ACs. The treated coal based AC cathodes had higher maximum power densities in MFCs (2450 ± 40 mW m-2) than the other AC cathodes or a Pt/C cathode (2100 ± 1 mW m-2). These results show that reduced oxygen abundance and increased nitrogen functionalities on the AC surface can increase catalytic performance for oxygen reduction in neutral media. © 2013 Elsevier B.V. All rights reserved.

  16. Mineralogy of telluride-bearing epithermal ores in the Kassiteres-Sappes area, western Thrace, Greece

    Science.gov (United States)

    Voudouris, P.; Tarkian, M.; Arikas, K.

    2006-05-01

    The Kassiteres-Sappes district represents a multi-centered, porphyry-epithermal system developed during the Oligocene to Miocene at a composite calc-alkaline to high-K calc-alkaline volcanic edifice. Precious and base metal mineralization postdates the emplacement of dacite and rhyolite porphyries and is partly superimposed on earlier microdiorite-related porphyry-style mineralization exposed at the Koryfes Hill prospect. A second mineralized porphyry-type system genetically related to a dacite porphyry body developed near the St Demetrios deposit. Tellurides occur mainly at the St Barbara prospect and the St Demetrios deposit. Based on petrographic, electron microprobe, and scanning electron microscope analyses, hessite, petzite, sylvanite, altaite, stützite and native tellurium occur in the St Barbara prospect. These tellurium-bearing minerals are hosted in intermediate-sulfidation type veins and accompanied by pyrite, chalcopyrite, tetrahedrite-group minerals, galena and native gold/electrum. The St Demetrios mineralization includes hessite, altaite, stützite, and tetradymite in close spatial relation to a high-sulfidation assemblage composed of enargite, chalcopyrite, goldfieldite, and native gold. Tellurides were deposited at logfTe2 values of -8.5 to -7.1 and logfS2 values of -10.7 to -7.9 (275 °C). The ore systems are characterized by Au, Ag, Te, Bi, and Mo, which suggests a magmatic contribution to the mineralizing fluids. Ore-forming components were likely derived from both the dacite and rhyolite porphyries.

  17. Ore mineralogy and textural zonation in the world-class epithermal Waihi Vein System, Hauraki Goldfield

    Science.gov (United States)

    Mauk, Jeffrey L.; Skinner, Erin G; Fyfe, Sarah J; Menzies, Andrew H; Lowers, Heather A.; Koenig, Alan E.

    2016-01-01

    The Waihi district in the Hauraki Goldfield of New Zealand contains adularia-sericite epithermal gold-silver veins that have produced more than 7.7 Moz gold. The outermost veins of the district (Martha, Favona, Moonlight, and Cowshed) contain abundant colloform, cherty, and black quartz fill textures, with minor crustiform and massive quartz. The central veins (Amaranth, Trio, and Union) contain predominantly massive and crustiform textures, and these veins are also commonly coarser grained than outermost veins. Pyrite, sphalerite, galena, chalcopyrite, electrum, and acanthite occur in both outermost and central veins; base metal sulfide minerals typically increase in abundance in deeper samples. Antimony-, arsenic-, and selenium-bearing minerals are most abundant in the Favona and Moonlight veins, whereas base metal sulfide minerals are more abundant in the central veins at Correnso. Throughout the Waihi vein system, electrum is by far the most widespread, abundant, and significant gold-bearing mineral, but LA-ICP-MS analyses show that arsenian pyrite also contains some gold. Mineralogical and textural data are consistent with the central veins forming at a deeper structural level, or from hydrothermal fluids with different chemistry, or both.

  18. Antibody-mediated Targeting of the Urokinase-type Plasminogen Activator Proteolytic Function Neutralizes Fibrinolysis in Vivo

    DEFF Research Database (Denmark)

    Lund, Ida K.; Jögi, Annika; Rono, Birgitte

    2008-01-01

    fibrinolysis in tissue-type plasminogen activator (tPA)-deficient mice, resulting in a phenotype mimicking that of uPA;tPA double deficient mice. Importantly, this is the first report demonstrating specific antagonist-directed targeting of mouse uPA at the enzyme activity level in a normal physiological...

  19. Effect of disulphide bond position on salt resistance and LPS-neutralizing activity of α-helical homo-dimeric model antimicrobial peptides.

    Science.gov (United States)

    Nan, Yong Hai; Shin, Song Yub

    2011-11-01

    To investigate the effects of disulphide bond position on the salt resistance and lipopolysaccharide (LPS)-neutralizing activity of α-helical homo-dimeric antimicrobial peptides (AMPs), we synthesized an α-helical model peptide (K6L4W1) and its homo-dimeric peptides (di-K(6)L(4)W(1)-N, di-K(6)L(4)W(1)-M, and di-K(6)L(4)W(1)-C) with a disulphide bond at the N-terminus, the central position, and the C-terminus of the molecules, respectively. Unlike (6)L(4)W(1) and di-K(6)L(4)W(1)-M, the antimicrobial activity of di-K(6)L(4)W(1)-N and di-K(6)L(4)W(1)-C was unaffected by 150 mM NaCl. Both di-K(6)L(4)W(1)-N and di-K(6)L(4)W(1)-C caused much greater inhibitory effects on nitric oxide (NO) release in LPS-induced mouse macrophage RAW 264.7 cells, compared to di-K(6)L(4)W(1)-M. Taken together, our results indicate that the presence of a disulphide bond at the N- or C-terminus of the molecule, rather than at the central position, is more effective when designing salt-resistant α-helical homo-dimeric AMPs with potent antimicrobial and LPS-neutralizing activities. [BMB reports 2011; 44(11): 747-752].

  20. Mineralogy, alteration patterns, geochemistry, and fluid properties of the Ag-Au epithermal deposit Nová Baňa, Slovakia

    Science.gov (United States)

    Majzlan, Juraj; Berkh, Khulan; Kiefer, Stefan; Koděra, Peter; Fallick, Anthony E.; Chovan, Martin; Bakos, František; Biroň, Adrián; Ferenc, Štefan; Lexa, Jaroslav

    2017-06-01

    part, primary fluid inclusions gave homogenization temperatures of 160-180 °C and similar low salinities. The secondary inclusions, however, show salinities up to 24 wt% NaCl eq., interpreted as fluid boiling almost to dryness. Isotopic composition of quartz and clay minerals is recalculated to fluid composition of -5.6 to -0.6 ‰ δ18Ofluid and -80 to -36 ‰ δDfluid, indicating mixed character of hydrothermal fluids falling between the compositions of magmatic and meteoric waters, with predominance of meteoric waters. Assuming hydrostatic pressure in the fluids, the measured data suggest paleodepths of ore formation of 50-170 m in the SW part of the ore deposit, 130-420 m in the SE and N parts, and a range of 120-470 m for the central part. These observations, comparison with other epithermal deposits in the Central Slovak volcanic field, and additional data from published literature show that Nová Baňa is a low- to intermediate sulfidation epithermal deposit, genetically associated to late rhyolitic volcanic activity in this area.

  1. Effect of forage quality on intake, chewing activity, faecal particle size distribution, and digestibility of neutral detergent fibre in sheep, goats, and llamas

    DEFF Research Database (Denmark)

    Jalali, Alireza; Nørgaard, Peder; Weisbjerg, Martin Riis

    2012-01-01

    into six sieving fractions with pore sizes in the 2.4–0.1 mm range and a bottom bowl. The dimension of each particle in sub-samples from each fraction was measured using image analysis. The DM intake per metabolic body weight (BW) was higher in sheep and llamas fed GH than in those animals fed GSS (P ...This study investigated the effect of forage quality on intake, eating and ruminating activities, faecal particle size distribution, and neutral detergent fibre (NDF) digestibility in three ruminating species. The experimental design included ad libitum feeding of three ruminating species with two.......05). Sheep and goats had a higher NDF intake per kg BW than did llamas when fed GSS (P intake, ruminating, and in total chewing per kg of DM and NDF intakes were higher when GSS was fed (P

  2. The Marianas-San Marcos vein system: characteristics of a shallow low sulfidation epithermal Au-Ag deposit in the Cerro Negro district, Deseado Massif, Patagonia, Argentina

    Science.gov (United States)

    Vidal, Conrado Permuy; Guido, Diego M.; Jovic, Sebastián M.; Bodnar, Robert J.; Moncada, Daniel; Melgarejo, Joan Carles; Hames, Willis

    2016-08-01

    The Cerro Negro district, within the Argentinian Deseado Massif province, has become one of the most significant recent epithermal discoveries, with estimated reserves plus resources of ˜6.7 Moz Au equivalent. The Marianas-San Marcos vein system contains about 70 % of the Au-Ag resources in the district. Mineralization consists of Upper Jurassic (155 Ma) epithermal Au- and Ag-rich veins of low to intermediate sulfidation style, hosted in and genetically related to Jurassic intermediate composition volcanic rocks (159-156 Ma). Veins have a complex infill history, represented by ten stages with clear crosscutting relationships that can be summarized in four main episodes: a low volume, metal-rich initial episode (E1), an extended banded quartz episode with minor mineralization (E2), a barren waning stage episode (E3), and a silver-rich late tectonic-hydrothermal episode (E4). The first three episodes are interpreted to have formed at the same time and probably from fluids of similar composition: a 290-230 °C fluid dominated by meteoric and volcanic waters (-3‰ to -0‰ δ18Owater), with sulfur (-1 to -2 ‰ δ34Swater). Metal was mainly precipitated at the beginning of vein formation (episode 1) due to a combination of boiling at ˜600 to 800 m below the paleowater table, and associated mixing/cooling processes, as evidenced by sulfide-rich bands showing crustiform-colloform quartz, adularia, and chlorite-smectite banding. During episodes 2 and 3, metal contents progressively decrease during continuing boiling conditions, and veins were filled by quartz and calcite during waning stages of the hydrothermal system, and the influx of bicarbonate waters (-6 to -8.5 ‰ δ18Owater). Hydrothermal alteration is characterized by proximal illite, adularia, and silica zone with chlorite and minor epidote, intermediate interlayered illite-smectite and a distal chlorite halo. This assemblage is in agreement with measured fluid inclusion temperatures. A striking aspect of the

  3. Hydrologic models of modern and fossil geothermal systems in the Great Basin: Genetic implications for epithermal Au-Ag and Carlin-type gold deposits

    Science.gov (United States)

    Person, M.; Banerjee, A.; Hofstra, A.; Sweetkind, D.; Gao, Y.

    2008-01-01

    The Great Basin region in the western United States contains active geothermal systems, large epithermal Au-Ag deposits, and world-class Carlin-type gold deposits. Temperature profiles, fluid inclusion studies, and isotopic evidence suggest that modern and fossil hydrothermal systems associated with gold mineralization share many common features, including the absence of a clear magmatic fluid source, discharge areas restricted to fault zones, and remarkably high temperatures (>200 ??C) at shallow depths (200-1500 m). While the plumbing of these systems varies, geochemical and isotopic data collected at the Dixie Valley and Beowawe geothermal systems suggest that fluid circulation along fault zones was relatively deep (>5 km) and comprised of relatively unexchanged Pleistocene meteoric water with small (water line (MWL). Many fossil ore-forming systems were also dominated by meteoric water, but usually exhibit ??18O fluid-rock interactions with larger shifts of 5???-20??? from the MWL. Here we present a suite of two-dimensional regional (100 km) and local (40-50 km) scale hydrologic models that we have used to study the plumbing of modern and Tertiary hydrothermal systems of the Great Basin. Geologically and geophysically consistent cross sections were used to generate somewhat idealized hydrogeologic models for these systems that include the most important faults, aquifers, and confining units in their approximate configurations. Multiple constraints were used, including enthalpy, ??18O, silica compositions of fluids and/or rocks, groundwater residence times, fluid inclusion homogenization temperatures, and apatite fission track anomalies. Our results suggest that these hydrothermal systems were driven by natural thermal convection along anisotropic, subvertical faults connected in many cases at depth by permeable aquifers within favorable lithostratigraphic horizons. Those with minimal fluid ?? 18O shifts are restricted to high-permeability fault zones and

  4. Effects of physically effective neutral detergent fiber content on dry matter intake, digestibility, and chewing activity in Korean native goats ( fed with total mixed ration

    Directory of Open Access Journals (Sweden)

    Se Young Jang

    2017-10-01

    Full Text Available Objective This experiment was to determine proper physical traits in the diet for goats by investigating the effects of physically effective neutral detergent fiber (peNDF content on dry matter intake (DMI, digestibility, and chewing activity in black goats fed with total mixed ration (TMR. Methods Six growing wethers of Korean native black goats (Capra hircus coreanae aged 8 months and weighing between 26.9 kg and 27.1 kg (27.03±5.05 kg were used in this experiment. Three diets of varying peNDF content were obtained by original TMR (T1, 12,000 rpm grinding (T2, and 15,500 rpm grinding (T3 of the same TMR diet. The peNDF1.18 content of the experimental diets was 23.85%, 21.71%, and 16.22% for T1, T2, and T3, respectively. Results Average daily gain (ADG was higher in T2 group compared to those of the control and T3 groups, but ADG and DMI were not affected by the dietary particle size and peNDF content. Also, there was no difference between apparent nutrient digestibility of dry matter, crude fiber, ether extract, neutral detergent fiber, and acid detergent fiber. Although there was no significant difference, rumination and total chewing time were associated with decreased peNDF content. Conclusion The feeding of peNDF-based TMR showed no impact on apparent nutrient digestibility and nitrogen balance. Further studies are required with a wider range of dietary peNDF level and particle size to better identify the effect of dietary peNDF and particle size on chewing activity and performance in goats.

  5. The spike protein of the emerging betacoronavirus EMC uses a novel coronavirus receptor for entry, can be activated by TMPRSS2, and is targeted by neutralizing antibodies.

    Science.gov (United States)

    Gierer, Stefanie; Bertram, Stephanie; Kaup, Franziska; Wrensch, Florian; Heurich, Adeline; Krämer-Kühl, Annika; Welsch, Kathrin; Winkler, Michael; Meyer, Benjamin; Drosten, Christian; Dittmer, Ulf; von Hahn, Thomas; Simmons, Graham; Hofmann, Heike; Pöhlmann, Stefan

    2013-05-01

    The novel human coronavirus EMC (hCoV-EMC), which recently emerged in Saudi Arabia, is highly pathogenic and could pose a significant threat to public health. The elucidation of hCoV-EMC interactions with host cells is critical to our understanding of the pathogenesis of this virus and to the identification of targets for antiviral intervention. Here we investigated the viral and cellular determinants governing hCoV-EMC entry into host cells. We found that the spike protein of hCoV-EMC (EMC-S) is incorporated into lentiviral particles and mediates transduction of human cell lines derived from different organs, including the lungs, kidneys, and colon, as well as primary human macrophages. Expression of the known coronavirus receptors ACE2, CD13, and CEACAM1 did not facilitate EMC-S-driven transduction, suggesting that hCoV-EMC uses a novel receptor for entry. Directed protease expression and inhibition analyses revealed that TMPRSS2 and endosomal cathepsins activate EMC-S for virus-cell fusion and constitute potential targets for antiviral intervention. Finally, EMC-S-driven transduction was abrogated by serum from an hCoV-EMC-infected patient, indicating that EMC-S-specific neutralizing antibodies can be generated in patients. Collectively, our results indicate that hCoV-EMC uses a novel receptor for protease-activated entry into human cells and might be capable of extrapulmonary spread. In addition, they define TMPRSS2 and cathepsins B and L as potential targets for intervention and suggest that neutralizing antibodies contribute to the control of hCoV-EMC infection.

  6. Purification and Structural Characterization of a Novel Water-Soluble Neutral Polysaccharide from Cantharellus cibarius and Its Immunostimulating Activity in RAW264.7 Cells

    Directory of Open Access Journals (Sweden)

    Long Chen

    2017-01-01

    Full Text Available Polysaccharide is one of the important active ingredients of Cantharellus cibarius. The aims of this work were to analyze preliminary characterization and to investigate immunostimulating activity of a novel water-soluble neutral polysaccharide named JP1, which was purified from the fruiting body of Cantharellus cibarius using DEAE-FF chromatography and Sephadex G-100 chromatography. The characteristics of JP1 were determined by HPGPC, FT-IR spectra, gas chromatography, and Congo Red Method. Immunostimulating activity of JP1 was investigated in RAW264.7 cells. Results indicated that JP1 consisted of L-Arabinose, D-Mannose, D-Glucose, and D-Galactose in a molar ratio of 1 : 1.06 : 1.95 : 1.17 with a molecular weight of 336 kDa. JP1 is nontoxic to RAW264.7 cells at this concentration range (62.5–1000 μg/mL. Furthermore, JP1 can promote mouse peritoneal macrophages to secrete NO and enhance the secretion of macrophages’ cytokines IL-6 in RAW264.7 cells. These results suggested that JP1 could have potential immunostimulating activity applications as medicine or functional food.

  7. Effect of activation and preactivation on the mechanical behavior and neutral position of stainless steel and beta-titanium T-loops.

    Science.gov (United States)

    de Castro, Saúl Matos; Moreira, Rui; Braga, Ana Cristina; Ferreira, Afonso Pinhão; Pollmann, Maria Cristina

    2015-07-01

    To quantify, for each activation, the effect of preactivations of differing distribution and intensity on the neutral position of T-loops (7-mm height), specifically the horizontal force, moment to force (M/F) ratio, and load to deflection ratio. A total 100 loops measuring 0.017 × 0.025 inches in cross-section were divided into two groups (n = 50 each) according to composition, either stainless steel or beta-titanium. The two groups were further divided into five subgroups, 10 loops each, corresponding to the five preactivations tested: preactivations with occlusal distribution (0°, 20°, and 40°), gingival distribution (20°), and occlusal-gingival distribution (40°). The loops were subjected to a total activation of 6-mm with 0.5-mm iterations. Statistical analysis was performed using comprised ANOVA and Bonferoni multiple comparison tests, with a significance level of 5%. The location and intensity of preactivation influenced the force intensity. For the M/F ratio, the highest value achieved without preactivation was lower than the height of the loop. Without preactivation, the M/F ratio increased with activation, while the opposite effect was observed with preactivation. The increase in the M/F ratio was greater when the preactivation distribution was partially or fully gingival. Depending on the preactivation distribution, displacement of uprights is higher or lower than the activation, which is a factor to consider in clinical practice.

  8. Neutralization of pharmacological and toxic activities of Bothrops jararacussu snake venom and isolated myotoxins by Serjania erecta methanolic extract and its fractions

    Directory of Open Access Journals (Sweden)

    RS Fernandes

    2011-01-01

    Full Text Available Most of the snakebites recorded in Brazil are caused by the Bothrops genus. Given that the local tissue damage caused by this genus cannot be treated by antivenom therapy, numerous studies are focusing on supplementary alternatives, such as the use of medicinal plants. Serjania erecta has already demonstrated anti-inflammatory, antiseptic and healing properties. In the current study, the aerial parts of S. erecta were extracted with methanol, then submitted to chromatographic fractionation on a Sephadex LH20 column and eluted with methanol, which resulted in four main fractions. The crude extract and fractions neutralized the toxic activities of Bothrops jararacussu snake venom and isolated myotoxins (BthTX-I and II. Results showed that phospholipase A2, fibrinogenolytic, myotoxic and hemorrhagic activities were inhibited by the extract. Moreover, the myotoxic and edematous activities induced by BthTX-I, and phospholipase A2 activity induced by BthTX-II, were inhibited by the extract of S. erecta and its fraction. The clotting time on bovine plasma was significantly prolonged by the inhibitory action of fractions SF3 and SF4. This extract is a promising source of natural inhibitors, such as flavonoids and tannins, which act by forming complexes with metal ions and proteins, inhibiting the action of serineproteases, metalloproteases and phospholipases A2.

  9. Iron-Carbonyl-Catalyzed Redox-Neutral [4+2] Annulation of N-H Imines and Internal Alkynes by C-H Bond Activation.

    Science.gov (United States)

    Jia, Teng; Zhao, Chongyang; He, Ruoyu; Chen, Hui; Wang, Congyang

    2016-04-18

    Stoichiometric C-H bond activation of arenes mediated by iron carbonyls was reported by Pauson as early as in 1965, yet the catalytic C-H transformations have not been developed. Herein, an iron-catalyzed annulation of N-H imines and internal alkynes to furnish cis-3,4-dihydroisoquinolines is described, and represents the first iron-carbonyl-catalyzed C-H activation reaction of arenes. Remarkablely, this is also the first redox-neutral [4+2] annulation of imines and alkynes proceeding by C-H activation. The reaction also features only cis stereoselectivity and excellent atom economy as neither base, nor external ligand, nor additive is required. Experimental and theoretical studies reveal an oxidative addition mechanism for C-H bond activation to afford a dinuclear ferracycle and a synergetic diiron-promoted H-transfer to the alkyne as the turnover-determining step. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Glucose Administration Enhances fMRI Brain Activation and Connectivity Related to Episodic Memory Encoding for Neutral and Emotional Stimuli

    Science.gov (United States)

    Parent, Marise B.; Krebs-Kraft, Desiree L.; Ryan, John P.; Wilson, Jennifer S.; Harenski, Carla; Hamann, Stephan

    2011-01-01

    Glucose enhances memory in a variety of species. In humans, glucose administration enhances episodic memory encoding, although little is known regarding the neural mechanisms underlying these effects. Here we examined whether elevating blood glucose would enhance functional MRI (fMRI) activation and connectivity in brain regions associated with…

  11. Enzymatic characterization, antigenic cross-reactivity and neutralization of dermonecrotic activity of five Loxosceles spider venoms of medical importance in the Americas.

    Science.gov (United States)

    Barbaro, Katia Cristina; Knysak, Irene; Martins, Rosana; Hogan, Christopher; Winkel, Ken

    2005-03-15

    Loxosceles spiders have a wide distribution in the temperate and tropical regions of the world. Loxoscelism is characterized by necrotic skin ulceration at the bite site and, less commonly, a systemic illness that may be fatal. The purpose of this study was to characterize and compare aspects of the major medically important Loxosceles spider venoms in a standardized manner, particularly considering their neutralization by two Brazilian antivenoms. By SDS-PAGE (12% acrylamide), Loxosceles deserta, Loxosceles gaucho, Loxosceles intermedia, Loxosceles laeta and Loxosceles reclusa venoms had similar electrophoretic profiles, with the major protein bands of 32-35 kDa. All venoms exhibited gelatinolytic, caseinolytic and fibrinogenolytic activities in vitro with a large array of proteases, mainly between 18.1 and 31.8 kDa. Most of these enzymes were metalloproteases as this activity was abolished by 1,10-phenanthroline. Hyaluronidase activity was detected in a protein band of approximately 44 kDa in all venoms. Sphingomyelinase activity was demonstrated in all five venoms. Antigenic cross-reactivity, by Western blotting, was also observed among all venoms studied using commercial equine antivenoms produced in Brazil (Institute Butantan and CPPI). These antivenoms recognized mainly components between 25 and 40 kDa in all venoms with several minor components of >89 kDa. Strong cross-reactivity was also seen among all venoms through the ELISA technique (titre range: 64,000-512,000). All venoms (5 microg doses) induced a similar local reaction when injected intradermally into the flank of rabbits, demonstrating dermonecrosis, hemorrhage, vasoconstriction, edema, and erythema. However, no reaction was observed when each venom was pre-incubated (1 h, 37 degrees C) with Brazilian commercial sera prior to injection. The antivenoms also abolished the sphingomyelinase activity in vitro, suggesting the venoms of the major medically important Loxosceles spider species have

  12. Epithermal neutron activation analysis investigation of Clarion-Clipperton abyssal plane clay and polymetallic micronodules

    Energy Technology Data Exchange (ETDEWEB)

    Duliu, O.G. [University of Bucharest, Department of Atomic and Nuclear Physics, P.O. Box MG-11, 077125 Magurele, Ilfov (Romania)], E-mail: duliu@b.astral.ro; Cristache, C.I. [National Institute of Research and Development for Physics and Nuclear Engineering ' Horia-Hulubei' , P.O. Box MG-6, 077125 Magurele, Ilfov (Romania)], E-mail: ocarmen@ifin.nipne.ro; Culicovc, O.A. [Joint Institute of Nuclear Research, 6, Joliot Curie str., 141980 Dubna (Russian Federation)], E-mail: otilia_culicov@yahoo.com; Frontasyeva, M.V. [Joint Institute of Nuclear Research, 6, Joliot Curie str., 141980 Dubna (Russian Federation)], E-mail: marina@nf.jinr.ru; Szobotca, S.A. [National Institute of Geoecology and Marine Geology, 34 Dimitrie Onciul str., 024504 Bucharest (Romania)], E-mail: szobi@geoecomar.ro; Toma, M. [National Institute of Research and Development for Physics and Nuclear Engineering ' Horia-Hulubei' , P.O. Box MG-6, 077125 Magurele, Ilfov (Romania)

    2009-05-15

    The content of seven major (Na, Al, Cl, Mn, K, Ca, Ti, Fe) and 30 trace (Sc, V, Cr, Ni, Co, Zn, Cu, As, Sr, Rb, Zr, Mo, Sn, In, Sb, Ba, Cs, La, Ce, Nd, Eu, Sm, Tb, Dy, Yb, Hf, Ta, W, Th, U) elements determined by INAA in 13 samples of abyssal clay and two samples of micronodules collected from the North pacific Ocean Clarion-Clipperton abyssal plane is presented and discussed with respect to some rocks models.

  13. Proterozoic low-sulfidation epithermal Au-Ag mineralization in the Mallery Lake area, Nunavut, Canada

    Science.gov (United States)

    Turner, William; Richards, Jeremy; Nesbitt, Bruce; Muehlenbachs, Karlis; Biczok, John

    2001-08-01

    The Mallery Lake area contains pristine examples of ancient precious metal-bearing low-sulfidation epithermal deposits. The deposits are hosted by rhyolitic flows of the Early Proterozoic Pitz Formation, but are themselves apparently of Middle Proterozoic age. Gold mineralization occurs in stockwork quartz veins that cut the rhyolites, and highest gold grades (up to 24 g/t over 30 cm) occur in the Chalcedonic Stockwork Zone. Quartz veining occurs in two main types: barren A veins, characterized by fine- to coarse-grained comb quartz, with fluorite, calcite, and/or adularia; and mineralized B veins, characterized by banded chalcedonic silica and fine-grained quartz, locally intergrown with fine-grained gold or electrum. A third type of quartz vein (C), which crosscuts B veins at one locality, is characterized by microcrystalline quartz intergrown with fine-grained hematite and rare electrum. Fluid inclusions in the veins occur in two distinct assemblages. Assemblage 1 inclusions represent a moderate temperature (Th=150 to 220 °C), low salinity (~1 eq. wt% NaCl, with trace CO2), locally boiling fluid; this fluid type is found in both A and B veins and is thought to have been responsible for Au-Ag transport and deposition. Assemblage 2 inclusions represent a lower temperature (Th=90 to 150 °C), high salinity calcic brine (23 to 31 wt% CaCl2-NaCl), which occurs as primary inclusions only in the barren A veins. Assemblage 1 and 2 inclusions occur in alternating quartz growth bands in the A-type veins, where they appear to represent alternating fluxes of dilute fluid and local saline groundwater. No workable primary fluid inclusions were observed in the C veins. The A-vein quartz yields δ18O values from 8.3 to 14.5‰ (average=10.9±1.7‰ [1σ], n=30), whereas δ18O values for B-vein quartz range from 11.2 to 14.0‰ (average=13.0±0.9‰, n=12). Calculated δ18OH2O values for the dilute mineralizing fluid from B veins range from -2.6 to 0.2‰ (average=-0.8±0.9

  14. ESR-dosimetry in thermal and epithermal neutron fields for application in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Tobias

    2016-01-22

    Dosimetry is essential for every form of radiotherapy. In Boron Neutron Capture Therapy (BNCT) mixed neutron and gamma fields have to be considered. Dose is deposited in different neutron interactions with elements in the penetrated tissue and by gamma particles, which are always part of a neutron field. The therapeutic dose in BNCT is deposited by densely ionising particles, originating from the fragmentation of the isotope boron-10 after capture of a thermal neutron. Despite being investigated for decades, dosimetry in neutron beams or fields for BNCT remains complex, due to the variety in type and energy of the secondary particles. Today usually ionisation chambers combined with metal foils are used. The applied techniques require extensive effort and are time consuming, while the resulting uncertainties remain high. Consequently, the investigation of more effective techniques or alternative dosimeters is an important field of research. In this work the possibilities of ESR-dosimeters in those fields have been investigated. Certain materials, such as alanine, generate stable radicals upon irradiation. Using Electron Spin Resonance (ESR) spectrometry the amount of radicals, which is proportional to absorbed dose, can be quantified. Different ESR detector materials have been irradiated in the thermal neutron field of the research reactor TRIGA research reactor in Mainz, Germany, with five setups, generating different secondary particle spectra. Further irradiations have been conducted in two epithermal neutron beams. The detector response, however, strongly depends on the dose depositing particle type and energy. It is hence necessary to accompany measurements by computational modelling and simulation. In this work the Monte Carlo code FLUKA was used to calculate absorbed doses and dose components. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using amorphous track models. For the simulation, detailed models of

  15. High Spatial Resolution Studies of Epithermal Neutron Emission from the Lunar Poles: Constraints on Hydrogen Mobility

    Science.gov (United States)

    Boynton, W. V.; Droege, G. F.; Mitrofanov, I. G.; McClanahan, T. P.; Sanin, A. B.; Litvak, M. L.; Schaffner, M.; Chin, G.; Evans, L. G.; Garvin, J. B.; hide

    2012-01-01

    The data from the collimated sensors of the LEND instrument are shown to be of exceptionally high quality. Counting uncertainties are about 0.3% relative and are shown to be the only significant source of random error, thus conclusions based on small differences in count rates are valid. By comparison with the topography of Shoemaker crater, the spatial resolution of the instrument is shown to be consistent with the design value of 5 km for the radius of the circle over which half the counts from the lunar surface would be determined. The observed epithermal-neutron suppression factor due to the hydrogen deposit in Shoemaker crater of 0.25 plus or minus 0.04 cps is consistent with the collimated field-of-view rate of 1.7 cps estimated by Mitrofanov et al. (2010a). The statistical significance of the neutron suppressed regions (NSRs) relative to the larger surrounding polar region is demonstrated, and it is shown that they are not closely related to the permanently shadowed regions. There is a significant increase in H content in the polar regions independent of the H content of the NSRs. The non-NSR H content increases directly with latitude, and the rate of increase is virtually identical at both poles. There is little or no increase with latitude outside the polar region. Various mechanisms to explain this steep increase in the non-NSR polar H with latitude are investigated, and it is suggested that thermal volatilization is responsible for the increase because it is minimized at the low surface temperatures close to the poles.

  16. Mineralogy and geochemistry of El Dorado epithermal gold deposit, El Sauce district, central-northern Chile

    Science.gov (United States)

    Carrillo-Rosúa, J.; Morales-Ruano, S.; Morata, D.; Boyce, A. J.; Belmar, M.; Fallick, A. E.; Fenoll Hach-Alí, P.

    2008-03-01

    The El Dorado Au-Cu deposit is located in an extensive intra-caldera zone of hydrothermal alteration affecting Upper Cretaceous andesites of the Los Elquinos Formation at La Serena (≈ 29°47'S Lat., 70°43'W Long., Chile). Quartz-sulfide veins of economic potential are hosted by N25W and N20E fault structures associated with quartz-illite alteration (+supergene kaolinite). The main ore minerals in the deposit are pyrite, chalcopyrite ± fahlore (As/(As + Sb): 0.06-0.98), with electrum, sphalerite, galena, bournonite-seligmanite (As/(As + Sb): 0.21-0.31), marcasite, pyrrhotite being accessory phases. Electrum, with an Ag content between 32 and 37 at.%, occurs interstitial to pyrite aggregates or along pyrite fractures. Pyrite commonly exhibits chemical zonation with some zones up to 1.96 at.% As. Electron probe microanalyses of pyrite indicate that As-rich zones do not exhibit detectable Au values. Fluid inclusion microthermometry shows homogenization temperatures between 130 and 352 °C and salinities between 1.6 and 6.9 wt.% NaCl eq. Isotope data for quartz, ankerite and phyllosilicates and estimated temperatures show that δ18O and δD for the hydrothermal fluids were between 3 and 10‰ and between -95 and -75‰, respectively. These results suggest the mineralizing fluids were a mixture of meteoric and magmatic waters. An epithermal intermediate-sulfidation model is proposed for the formation of the El Dorado deposit.

  17. Chelpo - Kalate Choubak, Kashmar, NE Iran: an epithermal Sb-As deposit

    Science.gov (United States)

    Hanna, B.; Mogk, D. W.; Ghaderi, M.; Narimani, A.

    2002-05-01

    Chelpo - Kalate Choubak Sb-As deposit is located 65 km north of Kashmar (Khorasan Province), northeast Iran. The area is a part of Central Iran structural zone. Paleogene gray-red marls and interbeds of tuff, sandstone and conglomerate comprise the main part of lithological sequence in the area. Paleogene units are intruded by monzonitic and micro-granitic plutons. Mafic dykes (diabasic-andesitic) are also present. Paleogene sequences are intensely folded and faulted making complex anticline and syncline structures. The deposit consists of veins and veinlets. The host rocks to mineralization are the Paleogene unit and micro-granites. The mineralized zone can be traced for about 6 km from Chelpo village in the east to Kalate Choubak village to the west. Argillic, pyritic and small amounts of silicic alterations accompany the mineralization. The mineralogy in the veins is simple and includes stibnite, stibiconite, kermesite, realgar, orpiment, pyrite, iron-hydroxide, calcite, gypsum and a small amount of quartz. Crustifide, open space filling, comb and colloform textures are present in the veins. Electron microprobe study was conducted to identify gold in stibnite, pyrite and realgar, but only As was detected in pyrite and stibnite. Geochemical studies of the drill hole cores show a positive correlation between Au and Sb and negative correlation between Au and As. Gold content increases slightly with depth. On the basis of evidences such as geometry, texture and structure, alteration, mineralogy, geochemistry and paragenesis, Chelpo - Kalateh Choubak can be regarded as an epithermal deposit. It seems that the veins formed as a result of hydrothermal system driven by subvolcanic microgranites.

  18. Neutralizing properties of Musa paradisiaca L. (Musaceae) juice on phospholipase A2, myotoxic, hemorrhagic and lethal activities of crotalidae venoms.

    Science.gov (United States)

    Borges, M H; Alves, D L F; Raslan, D S; Piló-Veloso, D; Rodrigues, V M; Homsi-Brandeburgo, M I; de Lima, M E

    2005-04-08

    The use of plants as medicine has been referred to since ancient peoples, perhaps as early as Neanderthal man. Plants are a source of many biologically active products and nowadays they are of great interest to the pharmaceutical industry. The study of how people of different culture use plants in particular ways has led to the discovery of important new medicines. In this work, we verify the possible activity of Musa paradisiaca L. (Musaceae) against the toxicity of snake venoms. Musa paradisiaca, an important source of food in the world, has also been reported to be popularly used as an anti-venom. Interaction of Musa paradisiaca extract (MsE) with snake venom proteins has been examined in this study. Phospholipase A2 (PLA2), myotoxic and hemorrhagic activities, including lethality in mice, induced by crotalidae venoms were significantly inhibited when different amounts of MsE were mixed with these venoms before assays. On the other hand, mice that received MsE and venoms without previous mixture or by separated routes were not protected against venom toxicity. Partial chemical characterization of MsE showed the presence of polyphenols and tannins and they are known to non-specifically inactivate proteins. We suggest that these compounds can be responsible for the in vitro inhibition of the toxic effects of snake venoms. In conclusion, according to our results, using mice as experimental model, MsE does not show protection against the toxic effects of snake venoms in vivo, but if was very effective when the experiments were done in vitro.

  19. Multipurpose epithermal neutron beam on new research station at MARIA research reactor in Swierk-Poland

    Energy Technology Data Exchange (ETDEWEB)

    Gryzinski, M.A.; Maciak, M. [National Centre for Nuclear Research, Andrzeja Soltana 7, 05-400 Otwock-Swierk (Poland)

    2015-07-01

    MARIA reactor is an open-pool research reactor what gives the chance to install uranium fission converter on the periphery of the core. It could be installed far enough not to induce reactivity of the core but close enough to produce high flux of fast neutrons. Special design of the converter is now under construction. It is planned to set the research stand based on such uranium converter in the near future: in 2015 MARIA reactor infrastructure should be ready (preparation started in 2013), in 2016 the neutron beam starts and in 2017 opening the stand for material and biological research or for medical training concerning BNCT. Unused for many years, horizontal channel number H2 at MARIA research rector in Poland, is going to be prepared as a part of unique stand. The characteristics of the neutron beam will be significant advantage of the facility. High flux of neutrons at the level of 2x10{sup 9} cm{sup -2}s{sup -1} will be obtainable by uranium neutron converter located 90 cm far from the reactor core fuel elements (still inside reactor core basket between so called core reflectors). Due to reaction of core neutrons with converter U{sub 3}Si{sub 2} material it will produce high flux of fast neutrons. After conversion neutrons will be collimated and moderated in the channel by special set of filters and moderators. At the end of H2 channel i.e. at the entrance to the research room neutron energy will be in the epithermal energy range with neutron intensity at least at the level required for BNCT (2x10{sup 9} cm{sup -2}s{sup -1}). For other purposes density of the neutron flux could be smaller. The possibility to change type and amount of installed filters/moderators which enables getting different properties of the beam (neutron energy spectrum, neutron-gamma ratio and beam profile and shape) is taken into account. H2 channel is located in separate room which is adjacent to two other empty rooms under the preparation for research laboratories (200 m2). It is

  20. Colloidal and physical transport textures exhibited by electrum and naumannite in bonanza epithermal veins from western USA, and their significance

    Science.gov (United States)

    Saunders, James A.; Vikre, Peter G.; Unger, Derick L.; Beasley, Lee

    2010-01-01

    It is reasonably clear that disequilibrium or “far-from equilibrium” conditions lead to the formation of silica colloids and their deposition in many epithermal deposits. This implies ore-forming solutions had elevated concentrations of dissolved silica, well in excess of amorphous silica saturation. We have previously demonstrated that such colloidal silica particles were deposited in epithermal veins as silica gels and opal, which may later progress along a path to crystallize into more thermodynamically favored (less-soluble) silica phases such as quartz and chalcedony. Also, in some deposits, amorphous silica is co-deposited with precious-metal minerals, such as electrum in the banded super-bonanza ores of the Sleeper deposit (NV). Ore-mineral textures from some western USA bonanza epithermal ores indicate that two precious-metal phases (electrum and naumannite, Ag2Se) form colloidal particles that are transported by ore-forming fluids and are deposited either by aggregation (by sticking to other precious metal-particles) to make dendrites, or are deposited on the “lee” side of protrusion along vein walls (or perhaps by both processes). We can infer by analogy to silica that this also implies that ore-forming solutions contained elevated (supersaturated) dissolved concentrations of both gold and silver that formed colloidal particles under disequilibrium (often chaotic) conditions. Thus physical transport and deposition textures seem to indicate the presence of strongly precious-metal-enriched ore forming fluids, which led to (not surprisingly) the bonanza grades of these remarkable ores. What causes such a precious-metal-rich solution is debatable, but that is the subject of our continued investigations.

  1. Diverse subaerial and sublacustrine hot spring settings of the Cerro Negro epithermal system (Jurassic, Deseado Massif), Patagonia, Argentina

    Science.gov (United States)

    Guido, Diego M.; Campbell, Kathleen A.

    2012-06-01

    The Late Jurassic (~ 150 Ma) Cerro Negro volcanic-epithermal-geothermal system (~ 15 km2 area), Deseado Massif, Patagonia, Argentina, includes two inferred volcanic emission centers characterized by rhyolitic domes linked along NW-SE regional faults that are associated with deeper level Au/Ag mineralization to the NW, and with shallow epithermal quartz veins and mainly travertine surface hot spring manifestations to the SE. Some travertines are silica-replaced, and siliceous and mixed silica-carbonate geothermal deposits also are found. Five hot spring-related facies associations were mapped in detail, which show morphological and textural similarities to Pleistocene-Recent geothermal deposits at Yellowstone National Park (U.S.A.), the Kenya Rift Valley, and elsewhere. They are interpreted to represent subaerial travertine fissure ridge/mound deposits (low-flow spring discharge) and apron terraces (high-flow spring discharge), as well as mixed silica-carbonate lake margin and shallow lake terrace vent-conduit tubes, stromatolitic mounds, and volcano-shaped cones. The nearly 200 mapped fossil vent-associated deposits at Cerro Negro are on a geographical and numerical scale comparable with subaerial and sublacustrine hydrothermal vents at Mammoth Hot Springs, and affiliated with Yellowstone Lake, respectively. Overall, the Cerro Negro geothermal system yields paleoenvironmentally significant textural details of variable quality, owing to both the differential preservation potential of particular subaerial versus subaqueous facies, as well as to the timing and extent of carbonate diagenesis and silica replacement of some deposits. For example, the western fault associated with the Eureka epithermal quartz vein facilitated early silicification of the travertine deposits in the SE volcanic emission center, thereby preserving high-quality, microbial macro- and micro-textures of this silica-replaced "pseudosinter." Cerro Negro provides an opportunity to reconstruct

  2. Boron neutron capture therapy (BNCT) for glioblastoma multiforme using the epithermal neutron beam at the Brookhaven Medical Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Capala, J. [Brookhaven National Lab., Upton, NY (United States); Diaz, A.Z.; Chadha, M. [Univ. Hospital, State Univ. of New York, NY (United States)] [and others

    1997-12-31

    The abstract describes evaluation of boron neutron capture therapy (BNCT) for two groups of glioblastoma multiforme patients. From September 1994 to February 1996 15 patients have been treated. In September 1997 another 34 patients were examined. Authors determined a safe starting dose for BNCT using epithermal neutrons and BPA-F. They have also evaluated adverse effects of BNCT at this starting dose. Therapeutic effectiveness of this starting dose has been evaluated. No significant side effects from BPA-F infusion or BNCT treatment were observed in normal brains.

  3. Effect of spermine on the activity of synaptosomal plasma membrane Ca(2+)-ATPase reconstituted in neutral or acidic phospholipids.

    Science.gov (United States)

    Palacios, Javier; Sepúlveda, M Rosario; Salvador, J M; Mata, Ana M

    2003-04-01

    The activity of purified plasma membrane Ca(2+)-ATPase (PMCA) from pig brain was inhibited by spermine (a naturally occurring and highly abundant polycation in brain). The level of inhibition was dependent on the phospholipid used for reconstitution as well as on the intact or truncated state of the enzyme. An IC(50) value of 12.5 mM spermine was obtained for both, the intact protein plus calmodulin and the trypsin-digested protein, reconstituted in phosphatidylcholine (PC). In the absence of calmodulin the intact Ca(2+)-ATPase gave an IC(50) of 27 mM. This form was more sensitive to spermine inhibition when it was reconstituted with phosphatidylserine (PS), showing an IC(50) value of 2.5 mM spermine. However, the truncated form was less responsive to spermine inhibition, having an IC(50) value of 12.5 mM. Spermine has no effect on the affinity of the PMCA for Ca(2+) or ATP, but its effect on the protein is pH-dependent. It is suggested that spermine could bind to negatively charged residues on the ATPase with different accessibility, depending on the structural rearrangement of the protein. Further, when the protein is reconstituted in PS, spermine also binds to the lipid.

  4. Neutralization of radical toxicity by temperature-dependent modulation of extracellular SOD activity in coral bleaching pathogen Vibrio shiloi and its role as a virulence factor.

    Science.gov (United States)

    Murali, Malliga Raman; Raja, Subramaniya Bharathi; Devaraj, Sivasitambaram Niranjali

    2010-08-01

    Vibrio shiloi is the first and well-documented bacterium which causes coral bleaching, particularly, during summer, when seawater temperature is between 26 and 31 degrees C. Coral bleaching is the disruption of the symbiotic association between coral hosts and their photosynthetic microalgae zooxanthellae. This is either due to lowered resistance in corals to infection or increased virulence of the bacterium at the higher sea surface temperature. The concentration of the oxygen and resulting oxygen radicals produced by the zooxanthellae during photosynthesis are highly toxic to bacteria, which also assist corals in resisting the infection. Hence, in this study we examined the effect of different temperatures on the activity of a novel extracellular SOD in V. shiloi. We also partially characterized the SOD and clearly confirmed that the extracellular SOD produced by V. shiloi is Mn-SOD type, as it was not inhibited by H2O2 or KCN. Performing chemical susceptibility killing assay, we confirmed that extracellular SOD may act as first line of defense for the bacteria against the reactive oxygen species. Since, increased activity of novel Mn-SOD at higher temperature, leads to the neutralization of radical toxicity and facilitates the survival of V. shiloi. Hence, the extracellular Mn-SOD may be considered as a virulence factor.

  5. Gargamelle: first neutral current

    CERN Multimedia

    1973-01-01

    This event shows the real tracks produced in the 1200 litre Gargamelle bubble chamber that provided the first confirmation of a neutral current interaction. A neutrino interacts with an electron, the track of which is seen horizontally, and emerges as a neutrino without producing a muon. The discovery of the neutral current was announced in the CERN main auditorium in July 1973.

  6. The genesis of the slab window-related Arzular low-sulfidation epithermal gold mineralization (eastern Pontides, NE Turkey

    Directory of Open Access Journals (Sweden)

    Enver Akaryalı

    2013-07-01

    Full Text Available The Arzular mineralization is one of the best examples of epithermal gold deposits in the eastern Pontides orogenic belt. The mineralization is hosted by the subduction-related basaltic andesites and is mainly controlled by E–W and NE–SW trending fracture zones. The main ore minerals are galena, sphalerite, pyrite, chalcopyrite, tetrahedrite and gold. Homogenization temperatures of fluid inclusions are between 130 and 295 °C for quartz and between 90 and 133 °C for sphalerite. Sulphur isotope values obtained from pyrite, galena and sphalerite vary between −1.2‰ and 3‰, indicating that sulphur belongs to magmatic origin and was derived from the Lutetian non-adakitic granitic intrusions in the region. Oxygen isotope values are between 15.0‰ and 16.7‰, and hydrogen isotope values are between −87‰ and −91‰. The sulphur isotope thermometer yielded temperatures in the range of 244–291 °C for the ore formation. Our results support the hypothesis that the Arzular mineralization is a low-sulfidation epithermal gold deposit associated with non-adakitic subduction-related granitic magmas that were generated by slab window-related processes in a south-dipping subduction zone during the Lutetian.

  7. Boron neutron capture therapy (BNCT). Recent aspect, a change from thermal neutron to epithermal neutron beam and a new protocol

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Yoshinobu [Dept. of Neurosurgery National Kagawa Children' s Hospital, Zentsuji, Kagawa (Japan)

    1999-08-01

    Since 1968, One-hundred seventy three patients with glioblastoma (n=81), anaplastic astrocytoma (n=44), low grade astrocytoma (n=16) or other types of tumor (n=32) were treated by boron-neutron capture therapy (BNCT) using a combination of thermal neutron and BSH in 5 reactors (HTR n=13, JRR-3 n=1, MuITR n=98, KUR n=28, JRR-2 n=33). Out of 101 patients with glioma treated by BNCT under the recent protocol, 33 (10 glioblastoma, 14 anaplastic astrocytoma, 9 low grade astrocytoma) patients lived or have lived longer than 3 years. Nine of these 33 lived or have lived longer than 10 years. According to the retrospective analysis, the important factors related to the clinical results were tumor dose radiation dose and maximum radiation dose in thermal brain cortex. The result was not satisfied as it was expected. Then, we decided to introduce mixed beams which contain thermal neutron and epithermal neutron beams. KUR was reconstructed in 1996 and developed to be available to use mixed beams. Following the shutdown of the JRR-2, JRR-4 was renewed for medical use in 1998. Both reactors have capacity to yield thermal neutron beam, epithermal neutron beam and mixed beams. The development of the neutron source lead us to make a new protocol. (author)

  8. Statistical Evaluation of the Geochemical Data from Akoluk Epithermal Gold Area (Ulubey-Ordu), NE Turkey

    Science.gov (United States)

    Yaylalı-Abanuz, G.; Tüysüz, N.

    2009-04-01

    There are several economic epithermal gold deposits in the eastern Pontide arc basin in northeast of Turkey. These mineralizations are generally found as veins in NE-SW and NW-SE trending shear fractures. The presence of faults and associated suitable hydrothermal alteration in the study area has been important guide for the gold exploration. Since region is intensely covered with thick soil and rocks are exposed in limited areas, stream sediment and soil geochemistry studies are the most commonly used methods in the exploration of mineral deposits. In this study, the applicability of soil geochemistry surveys in the exploration of mineral deposits in areas of intense overburden is tested using statistical methods. A vein type gold occurence is confined to the fault zones crossing dacitic tuffs of Upper Cretaceous age. Faults appear to be a conjugate set of a shear system, striking N 45-50 E, and N 55-60 W dipping 80-85 SE and 70-80 NW respectively. Mineralization occurs generally as replacement of dacitic tuffs along the fault planes and less of void fillings. Main ore minerals are native gold, stibnite, zinkenite, pyrite, marcasite, realgar, orpiment, sphalerite, galena, chalcopyrite, malachite, and azurite, and the most common gangue mineral is barite. Soil is residual and well developed ranging in thickness from 0.5 m to 1 m. Elements analyzed and interpreted are the ones which are known to have close association with gold. Of these Au, Ag, Sb, As, Zn, Mo, W, and Ba show a single very significant anomaly pattern although several other small isolated anomalies are also recorded. The latter must be related to sampling artifacts. The significant one is circular in shape and has a diameter of approx. 200 m. It is strikingly of interest that anomaly shape does not imitate fracture system. This may be due to the fact that sampling interval is wider than the fault zones. However the circular pattern may suggest a granitic intrusion in subcrop as the main controller of

  9. Expression Patterns, Activities and Carbohydrate-Metabolizing Regulation of Sucrose Phosphate Synthase, Sucrose Synthase and Neutral Invertase in Pineapple Fruit during Development and Ripening

    Directory of Open Access Journals (Sweden)

    Yan-Li Yao

    2012-07-01

    Full Text Available Differences in carbohydrate contents and metabolizing-enzyme activities were monitored in apical, medial, basal and core sections of pineapple (Ananas comosus cv. Comte de paris during fruit development and ripening. Fructose and glucose of various sections in nearly equal amounts were the predominant sugars in the fruitlets, and had obvious differences until the fruit matured. The large rise of sucrose/hexose was accompanied by dramatic changes in sucrose phosphate synthase (SPS and sucrose synthase (SuSy activities. By contrast, neutral invertase (NI activity may provide a mechanism to increase fruit sink strength by increasing hexose concentrations. Furthermore, two cDNAs of Ac-sps (accession no. GQ996582 and Ac-ni (accession no. GQ996581 were first isolated from pineapple fruits utilizing conserved amino-acid sequences. Homology alignment reveals that the amino acid sequences contain some conserved function domains. Transcription expression analysis of Ac-sps, Ac-susy and Ac-ni also indicated distinct patterns related to sugar accumulation and composition of pineapple fruits. It suggests that differential expressions of multiple gene families are necessary for sugar metabolism in various parts and developmental stages of pineapple fruit. A cycle of sucrose breakdown in the cytosol of sink tissues could be mediated through both Ac-SuSy and Ac-NI, and Ac-NI could be involved in regulating crucial steps by generating sugar signals to the cells in a temporally and spatially restricted fashion.

  10. Functional Dependence for Calculation of Additional Real-Power Losses in a Double-Wound Supply Transformer Caused by Unbalanced Active Inductive Load in a Star Connection with an Insulated Neutral

    Science.gov (United States)

    Kostinskiy, Sergey S.; Troitskiy, Anatoly I.

    2016-01-01

    This article deals with the problem of calculating the additional real-power losses in double-wound supply transformers with voltage class 6 (10)/0,4 kV, caused by unbalanced active inductive load connected in a star connection with an insulated neutral. When solving the problem, authors used the theory of electric circuits, method of balanced…

  11. A microplate assay for the coupled transglycosylase-transpeptidase activity of the penicillin binding proteins; a vancomycin-neutralizing tripeptide combination prevents penicillin inhibition of peptidoglycan synthesis.

    Science.gov (United States)

    Kumar, Vidya P; Basavannacharya, Chandrakala; de Sousa, Sunita M

    2014-07-18

    A microplate, scintillation proximity assay to measure the coupled transglycosylase-transpeptidase activity of the penicillin binding proteins in Escherichia coli membranes was developed. Membranes were incubated with the two peptidoglycan sugar precursors UDP-N-acetyl muramylpentapeptide (UDP-MurNAc(pp)) and UDP-[(3)H]N-acetylglucosamine in the presence of 40 μM vancomycin to allow in situ accumulation of lipid II. In a second step, vancomycin inhibition was relieved by addition of a tripeptide (Lys-D-ala-D-ala) or UDP-MurNAc(pp), resulting in conversion of lipid II to cross-linked peptidoglycan. Inhibitors of the transglycosylase or transpeptidase were added at step 2. Moenomycin, a transglycosylase inhibitor, had an IC50 of 8 nM. Vancomycin and nisin also inhibited the assay. Surprisingly, the transpeptidase inhibitors penicillin and ampicillin showed no inhibition. In a pathway assay of peptidoglycan synthesis, starting from the UDP linked sugar precursors, inhibition by penicillin was reversed by a 'neutral' combination of vancomycin plus tripeptide, suggesting an interaction thus far unreported. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. The conserved N-terminus of human rhinovirus capsid protein VP4 contains membrane pore-forming activity and is a target for neutralizing antibodies.

    Science.gov (United States)

    Panjwani, Anusha; Asfor, Amin S; Tuthill, Tobias J

    2016-12-01

    Human rhinovirus is the causative agent of the common cold and belongs to the non-enveloped picornavirus family. A trigger such as receptor binding or low pH initiates conformational changes in the capsid that allow the virus to attach to membranes and form a pore for the translocation of viral RNA into the cytoplasm. We previously showed that recombinant capsid protein VP4 was able to form membrane pores. In this study, we show the N-terminus but not C-terminus of VP4 formed pores with properties similar to full-length VP4 and consistent with the size required for transfer of RNA. Sera against the N-terminus but not C-terminus of VP4 were shown to neutralize virus infectivity. Together, this suggests that the N-terminus of VP4 is responsible for membrane activity. This study contributes to an improved understanding of the mechanisms for involvement of VP4 in entry and its potential as an antiviral target.

  13. Hydrophobin fusion of an influenza virus hemagglutinin allows high transient expression in Nicotiana benthamiana, easy purification and immune response with neutralizing activity.

    Directory of Open Access Journals (Sweden)

    Nicolas Jacquet

    Full Text Available The expression of recombinant hemagglutinin in plants is a promising alternative to the current egg-based production system for the influenza vaccines. Protein-stabilizing fusion partners have been developed to overcome the low production yields and the high downstream process costs associated with the plant expression system. In this context, we tested the fusion of hydrophobin I to the hemagglutinin ectodomain of the influenza A (H1N1pdm09 virus controlled by the hybrid En2PMA4 transcriptional promoter to rapidly produce high levels of recombinant antigen by transient expression in agro-infiltrated Nicotiana benthamiana leaves. The fusion increased the expression level by a factor of ∼ 2.5 compared to the unfused protein allowing a high accumulation level of 8.6% of the total soluble proteins. Hemagglutinin was located in ER-derived protein bodies and was successfully purified by combining an aqueous-two phase partition system and a salting out step. Hydrophobin interactions allowed the formation of high molecular weight hemagglutinin structures, while unfused proteins were produced as monomers. Purified protein was shown to be biologically active and to induce neutralizing antibodies after mice immunization. Hydrophobin fusion to influenza hemagglutinin might therefore be a promising approach for rapid, easy, and low cost production of seasonal or pandemic influenza vaccines in plants.

  14. Polytopic vaccination with a live-attenuated dengue vaccine enhances B-cell and T-cell activation, but not neutralizing antibodies

    Directory of Open Access Journals (Sweden)

    Taweewun Hunsawong

    2017-03-01

    Full Text Available Dengue, caused by dengue viruses (DENVs, is the most common arboviral disease of humans. Several dengue vaccine candidates are at different stages of clinical development and one has been licensed. Inoculation with live-attenuated DENV constructs is an approach that has been used by vaccine developers. Unfortunately, the simultaneous injection of all four attenuated DENV serotypes (DENV1-4 into a single injection site (monotopic vaccination has been postulated to result in interference in the replication of some serotypes in favor of others, an important obstacle in obtaining a balanced immune response against all serotypes. Here, we demonstrate the virus replicative and immunostimulatory effects of polytopic monovalent dengue vaccination (PV in which, each of the four components of the tetravalent vaccine is simultaneously delivered to four different sites versus the more traditional monotopic tetravalent vaccination (MV in a non-human primate (NHP model. With the exception of DENV-2, there was no significant difference in detectable viral RNA levels between PV and MV inoculation. Interestingly, longer periods of detection and higher viral RNA levels were seen in the lymph nodes of NHPs inoculated PV compared to MV. Induction of lymph node dendritic cell maturation and of blood T- and B-cell activation showed different kinetics in PV inoculated NHPs compared to MV. The MV inoculated group showed earlier maturation of dendritic cells and activation of B and T cells compared to PV inoculated NHPs. A similar kinetic difference was also observed in the cytokine response: MV induced earlier cytokine responses compared to PV. However, similar levels of DENV neutralizing antibodies were observed in PV and MV NHPs. These findings indicate that cellular immune response after vaccination may be affected by the location of inoculation. Design of vaccine delivery may need to take into account the effects of locations of vaccine delivery of multiples

  15. Geologic setting and genesis of the Mule Canyon low-sulfidation epithermal gold-silver deposit, north-central Nevada

    Science.gov (United States)

    John, D.A.; Hofstra, A.H.; Fleck, R.J.; Brummer, J.E.; Saderholm, E.C.

    2003-01-01

    The Mule Canyon mine exploited shallow, low-sulfidation, epithermal Au-Ag deposits that lie near the west side of the Northern Nevada rift in northern Lander County, Nevada. Mule Canyon consists of six small deposits that contained premining reserves of about 8.2 Mt at an average grade of 3.81 g Au/tonne. It is an uncommon mafic end member of low-sulfidation Au-Ag deposits associated with tholeiitic bimodal basalt-rhyolite magmatism. The ore is hosted by a basalt-andesite eruptive center that formed between about 16.4 to 15.8 Ma during early mafic eruptions related to regionally extensive bimodal magmatism. Hydrothermal alteration and Au-Ag ores formed at about 15.6 Ma and were tightly controlled by north-northwest- to north-striking high-angle fault and breccia zones developed during rifting, emplacement of mafic dikes, and eruption of mafic lava flows. Hydrothermal alteration assemblages are zoned outward from fluid conduits in the sequence silica-adularia, adularia-smectite, smectite (intermediate argillic), and smectite-carbonate (propylitic). All alteration types contain abundant pyrite and/or marcasite ?? arsenopyrite. Field relations indicate that silica-adularia alteration is superimposed on argillic and propylitic alteration. Little or no steam-heated acid-sulfate alteration is present, probably the result of a near-surface water table during hydrothermal alteration and ore deposition. Two distinct ore types are present at Mule Canyon: early replacement and later open-space filling. Replacement ores consist of disseminated and vesicle-filling pyrite, marcasite, and arsenopyrite in argillically altered or weakly silicified rocks. Ore minerals consist of Au-bearing arsenopyrite and arsenian pyrite overgrowths on earlier-formed pyrite and marcasite. Open-space filling ores include narrow stockwork quartz-adularia veins, banded and crustiform opaline and chalcedonic silica-adularia veins, silica-adularia cemented breccias, and sparse carbonate-pyrite and

  16. Geological, mineralogical and geochemical characteristics of the Radzimowice Au As Cu deposit from the Kaczawa Mountains (Western Sudetes, Poland): an example of the transition of porphyry and epithermal style

    Science.gov (United States)

    Mikulski, Stanislaw Z.

    2005-03-01

    The sheeted quartz sulfide veins of the Radzimowice Au As Cu deposit in the Kaczawa Mountains are related to Upper Carboniferous post-collisional potassic magmatism of the composite Zelezniak porphyry intrusion. Multiple intrusive activity ranges from early calc-alkaline to sub-alkaline and alkaline rocks and is followed by multiple hydrothermal events. Early crustally derived dacitic magma has low mg# (electrum of two generations, and minor maldonite (Au2Bi). Fluid inclusions from various quartz generations co-genetic with base-metal sulfides and associated with carbonates, tellurides and non-refractory gold indicate fluids with moderate salinity (9 15 wt% NaCl equiv.) and a temperature and pressure drop from 350 to 190°C and 1.2 to 0.8 kbar, respectively. According to the result of the sulfur isotope fractionation geothermometer the temperature of base-metal crystallization was in the range from 322 to 289°C. Preliminary results of oxygen isotope studies of quartz from veins indicate a gradual increase in the proportion of meteoric water in the epithermal stage. The gold to silver ratio in ore samples with >3 ppm Au is about 1:5 (geometric mean). Hydrothermal alteration started with sericitization, pyritization, and kaolinitization in vein selvages followed by alkaline hydrothermal alteration of propylitic character (illitization and chloritization), albitization and carbonatization. The mineralization of the Radzimowice deposit is considered as related to alkaline magmatism and is characterized by the superposition of low-sulfidation epithermal mineralization on higher-temperature and deeper-seated mesothermal/porphyry style.

  17. Gold grade of epithermal gold ore at Lamuntet, Brang Rea, West Sumbawa District, West Nusa Tenggara Province, Indonesia

    Science.gov (United States)

    Ernawati, Rika; Idrus, Arifudin; TBMP, Himawan

    2017-06-01

    Lamuntet is one of gold ore mining area carried out by the Artisanal Small scale Gold Mining (ASGM) located in West Sumbawa, Indonesia. Most of the miners at this area are not the local miners but also those from other regions. Mineralization of this area is strong identified as low sulfidation epithermal system. There are two blocks of this mining location, namely, Ngelampar block with an area of 0.164 km2 and Song block with an area of 0.067 km2. This study was focused on Ngelampar block. The characteristic of epithermal system is the existence of quartz vein with comb, vuggy, and sugary texture. The aim of this research was to analyze the gold grade and other metals, such as Cu, Ag, Pb, As, Zn, and Hg. The research methods included literature study from previous researches, field work, laboratory work, and interpretation. The literature study was performed on previous researches with similar study area. The field work comprised of direct observation and sampling. Fieldwork was done for a week to obtain gold ore/vein. Sixteen samples were analyzed to obtain the grade of ore/metal. The Hg laboratory analysis was then performed on the six samples with the highest gold grade. Laboratory works were conducted at Intertek Jakarta by using Fire Assay (FA) for gold grade and Atomic Absorption Spectrophotometry (AAS) for Cu, Ag, Pb, As, Zn, and Hg. Results of the analysis showed the range of Au was grade (0.1 ppm - 27.8 ppm), Cu was 26 ppm -1740 ppm, Pb was 101 ppm- >4000 ppm, Zn of 73 ppm- >10,000 ppm, Ag of 3 ppm -185 ppm, As was 150 ppm-6530 ppm, and Hg of 0.08 ppm - 1.89 ppm. L1 and L15 had high grade for all values (Au, Ag, Zn, Cu, As, and Hg). Gold mineralization was formed as electrum because of Ag content is higher than 20%. Associated minerals of the samples in the study area were galena, sphalerite, arsenopyrite, and chalcopyrite which showed the characteristic of rich base metal of Pb, Zn, and Cu at LS epithermal.

  18. Genesis of Middle Miocene Yellowstone hotspot-related bonanza epithermal Au-Ag deposits, Northern Great Basin, USA

    Science.gov (United States)

    Saunders, J. A.; Unger, D. L.; Kamenov, G. D.; Fayek, M.; Hames, W. E.; Utterback, W. C.

    2008-09-01

    Epithermal deposits with bonanza Au-Ag veins in the northern Great Basin (NGB) are spatially and temporally associated with Middle Miocene bimodal volcanism that was related to a mantle plume that has now migrated to the Yellowstone National Park area. The Au-Ag deposits formed between 16.5 and 14 Ma, but exhibit different mineralogical compositions, the latter due to the nature of the country rocks hosting the deposits. Where host rocks were primarily of meta-sedimentary or granitic origin, adularia-rich gold mineralization formed. Where glassy rhyolitic country rocks host veins, colloidal silica textures and precious metal-colloid aggregation textures resulted. Where basalts are the country rocks, clay-rich mineralization (with silica minerals, adularia, and carbonate) developed. Oxygen isotope data from quartz (originally amorphous silica and gels) from super-high-grade banded ores from the Sleeper deposit show that ore-forming solutions had δ 18O values up to 10‰ heavier than mid-Miocene meteoric water. The geochemical signature of the ores (including their Se-rich nature) is interpreted here to reflect a mantle source for the “epithermal suite” elements (Au, Ag, Se, Te, As, Sb, Hg) and that signature is preserved to shallow crustal levels because of the similar volatility and aqueous geochemical behavior of the “epithermal suite” elements. A mantle source for the gold in the deposits is further supported by the Pb isotopic signature of the gold ores. Apparently the host rocks control the mineralization style and gangue mineralogy of ores. However, all deposits are considered to have derived precious metals and metalloids from mafic magmas related to the initial emergence of the Yellowstone hotspot. Basalt-derived volatiles and metal(loid)s are inferred to have been absorbed by meteoric-water-dominated geothermal systems heated by shallow rhyolitic magma chambers. Episodic discharge of volatiles and metal(loid)s from deep basaltic magmas mixed with

  19. Ore deposits and epithermal evidences associated with intra-magmatic faults at Aïn El Araâr-Oued Belif ring structure (NW of Tunisia)

    Science.gov (United States)

    Aissa, Wiem Ben; Aissa, Lassaâd Ben; Amara, Abdesslem Ben Haj; Tlig, Said; Alouani, Rabah

    2017-03-01

    Hydrothermal ore deposits at Aïn El Araâr-Oued Belif location are classified as epithermal deposits type. The ore bodies are hosted by upper Turonian (8-9 M.y) volcanic rhyodacitic complex. Polymetallic sulfide orebodies are mainly concentrated within intra-magmatic faults. Petrographic, XRD, and TEM-STEM investigations revealed that ore minerals are essentially, arsenopyrite, pyrite, chalcopyrite, pyrrhotite, hematite, goethite and magnetite with Au, Ag and Pt trace metals. Gangue minerals are mainly adularia, quartz, sericite, alunite, tridymite, chlorite, phlogopite and smectite. Epithermal alteration is well zoned with four successive characteristic zones: (1) zone of quartz-adularia-sericite and rare alunite; (2) zone of kaolinite and plagioclase albitization; (3) intermediate zone of illite-sericite; (4) sapropelic alteration type zone of chlorite-smectite and rare illite. This can be interpreted as a telescoping of two different acidity epithermal phases; low sulfidation (adularia-sericite) and high sulfidation (quartz-alunite), separated in time or due to a gradual increase of fluids acidity and oxicity within the same mineralization phase. Brecciated macroscopic facies with fragments hosting quartz-adularia-sericite minerals (low-sulfidation phase) without alunite, support the last hypothesis. Geodynamic context and mineral alteration patterns are closely similar to those of Maria Josefa gold mine at SE of Spain which exhibit a volcanic-hosted epithermal ore deposit in a similar vein system, within rhyolitic ignimbrites, altered to an argillic assemblage (illite-sericite abundant and subordinate kaolinite) that grades outwards into propylitic alteration (Sanger-von Oepen et al. (1990)). Mineralogical and lithologic study undertaken in the volcanic host rock at Aïn El Araâr-Oued Belif reveals a typical epithermal low-sulfidation and high-sulfidation ore deposits with dominance of low-sulfidation. Host rocks in these systems range from silicic to

  20. Internal vein texture and vein evolution of the epithermal Shila-Paula district, southern Peru

    Science.gov (United States)

    Chauvet, Alain; Bailly, Laurent; André, Anne-Sylvie; Monié, Patrick; Cassard, Daniel; Tajada, Fernando Llosa; Vargas, Juan Rosas; Tuduri, Johann

    2006-07-01

    The epithermal Shila-Paula Au-Ag district is characterized by numerous veins hosted in Tertiary volcanic rocks of the Western Cordillera (southern Peru). Field studies of the ore bodies reveal a systematic association of a main E-W vein with secondary N55-60°W veins—two directions that are also reflected by the orientation of fluid-inclusion planes in quartz crystals of the host rock. In areas where this pattern is not recognized, such as the Apacheta sector, vein emplacement seems to have been guided by regional N40°E and N40°W fractures. Two main vein-filling stages are identified. stage 1 is a quartz-adularia-pyrite-galena-sphalerite-chalcopyrite-electrum-Mn silicate-carbonate assemblage that fills the main E-W veins. stage 2, which contains most of the precious-metal mineralization, is divided into pre-bonanza and bonanza substages. The pre-bonanza substage consists of a quartz-adularia-carbonate assemblage that is observed within the secondary N45-60°W veins, in veinlets that cut the stage 1 assemblage, and in final open-space fillings. The two latter structures are finally filled by the bonanza substage characterized by a Fe-poor sphalerite-chalcopyrite-pyrite-galena-tennantite-tetrahedrite-polybasite-pearceite-electrum assemblage. The ore in the main veins is systematically brecciated, whereas the ore in the secondary veins and geodes is characteristic of open-space crystallization. Microthermometric measurements on sphalerite from both stages and on quartz and calcite from stage 2 indicate a salinity range of 0 to 15.5 wt% NaCl equivalent and homogenization temperatures bracketed between 200 and 330°C. Secondary CO2-, N2- and H2S-bearing fluid inclusions are also identified. The age of vein emplacement, based on 40Ar/39Ar ages obtained on adularia of different veins, is estimated at around 11 Ma, with some overlap between adularia of stage 1 (11.4±0.4 Ma) and of stage 2 (10.8±0.3 Ma). A three-phase tectonic model has been constructed to explain the

  1. Degradation of 32 emergent contaminants by UV and neutral photo-fenton in domestic wastewater effluent previously treated by activated sludge.

    Science.gov (United States)

    De la Cruz, N; Giménez, J; Esplugas, S; Grandjean, D; de Alencastro, L F; Pulgarín, C

    2012-04-15

    This study focuses on the removal of 32 selected micropollutants (pharmaceuticals, corrosion inhibitors and biocides/pesticides) found in an effluent coming from a municipal wastewater treatment plant (MWTP) based on activated sludge. Dissolved organic matter was present, with an initial total organic carbon of 15.9 mg L(-1), and a real global quantity of micropollutants of 29.5 μg L(-1). The treatments tested on the micropollutants removal were: UV-light emitting at 254 nm (UV(254)) alone, dark Fenton (Fe(2+,3+)/H(2)O(2)) and photo-Fenton (Fe(2+,3+)/H(2)O(2)/light). Different irradiation sources were used for the photo-Fenton experiences: UV(254) and simulated sunlight. Iron and H(2)O(2) concentrations were also changed in photo-Fenton experiences in order to evaluate its influence on the degradation. All the experiments were developed at natural pH, near neutral. Photo-Fenton treatments employing UV(254), 50 mg L(-1) of H(2)O(2), with and without adding iron (5 mg L(-1) of Fe(2+) added or 1.48 mg L(-1) of total iron already present) gave the best results. Global percentages of micropollutants removal achieved were 98 and a 97% respectively, after 30 min of treatments. As the H(2)O(2) concentration increased (10, 25 and 50 mg L(-1)), best degradations were observed. UV(254), Fenton, and photo-Fenton under simulated sunlight gave less promising results with lower percentages of removal. The highlight of this paper is to point out the possibility of the micropollutants degradation in spite the presence of DOM in much higher concentrations. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Metallogeny of the Gold Quadrilateral: style and characteristics of epithermal - subvolcanic mineralized structures, South Apuseni Mts., Romania

    Directory of Open Access Journals (Sweden)

    S̡erban-Nicolae Vlad

    2004-04-01

    Full Text Available The Romanian territory contains numerous ore deposits mined since pre-Roman times. An assessment of historical gold production of the Gold Quadri-lateral (GQ yielded a total estimate of 55.7 Moz of gold throughout an area of 2400 km2. Interpreted in terms of mineralization density this is 23,208 oz of gold/ km2. The geological setting of the GQ is represented mainly by Tertiary (14.7 My to 7.4 My calc-alkaline volcano-plutonic complexes of intermediate character in sedimentary basins of molasse type. These basins are tectonically controlled by NW-SE lineation across early Alpine magmatic products, i.e. subduction related Jurassic-Lower Cretaceous igneous association (island arc ophiolites and granitoids and Upper Cretaceous igneous association (banatites. The Tertiary magmatism is associated with extensional tectonics caused by NE escape of the Pannonian region during Upper Oligocene-Lower Miocene times. As a result of tectono-magmatic and mineralization-alteration characteristics, two metallogenetical types were separated in the GQ, i.e. calc-alkaline andesitic (CAM and sub-alkaline rhyodacitic (SRM. Both develop almost entirely low-sulfidation type of Au epithermal mineralization. However, two subtypes, -rich in sulfide (2-7% and -poor in sulfide (7-20% were delineated and correlated with CAM type and SRM type respectively. Furthermore, CAM is connected at deeper levels with Cu-Au+/-Mo porphyry systems in contrast with SRM, which is a non-porphyry environment. The Brad-Săcărâmb district contains mainly CAM type andesitic structures. It is a porphyry environment with epithermal low-sulfidation-rich sulfide vein halo (Barza, Troiţa-Bolcana deposits. However, a few SRM type patterns, such as Măgura Ţebii, Băiţa-Crăciuneşti and Săcărâmb, deposits exhibit Au-Ag-Te low-sulfidation-poor sulfide epithermal vein halo. The Zlatna-Stănija district exhibits similar characteristics, with Au-Ag+/-Pb, Zn veins in Cu-Au subvolcanic

  3. Generation of effective libraries by neutral drift.

    Science.gov (United States)

    Kaltenbach, Miriam; Tokuriki, Nobuhiko

    2014-01-01

    Neutral drift is a recently developed experimental technique used to identify superior starting points for protein engineering. Neutral drift explores accessible sequence space by repeated rounds of mutagenesis and selection to maintain wild-type function. Mutations that are largely neutral for the native function accumulate, and those that are highly detrimental are purged, yielding a library of high diversity and quality. This technique is useful in situations where laboratory evolution is at a dead end, i.e., when the enzyme activity intended for evolution proves recalcitrant to improvements or is too low to be detected.

  4. Evaluation of smallpox vaccines using variola neutralization.

    Science.gov (United States)

    Damon, Inger K; Davidson, Whitni B; Hughes, Christine M; Olson, Victoria A; Smith, Scott K; Holman, Robert C; Frey, Sharon E; Newman, Frances; Belshe, Robert B; Yan, Lihan; Karem, Kevin

    2009-08-01

    The search for a 'third'-generation smallpox vaccine has resulted in the development and characterization of several vaccine candidates. A significant barrier to acceptance is the absence of challenge models showing induction of correlates of protective immunity against variola virus. In this light, virus neutralization provides one of few experimental methods to show specific 'in vitro' activity of vaccines against variola virus. Here, we provide characterization of the ability of a modified vaccinia virus Ankara vaccine to induce variola virus-neutralizing antibodies, and we provide comparison with the neutralization elicited by standard Dryvax vaccination.

  5. Thermal and epithermal neutron fluence rate gradient measurements by PADC detectors in LINAC radiotherapy treatments-field

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, M. T., E-mail: mariate9590@gmail.com; Barros, H.; Pino, F.; Sajo-Bohus, L. [Universidad Simón Bolívar, Nuclear Physics Laboratory, Sartenejas, Caracas (Venezuela, Bolivarian Republic of); Dávila, J. [Física Médica C. A. and Universidad Central de Venezuela, Caracas (Venezuela, Bolivarian Republic of)

    2015-07-23

    LINAC VARIAN 2100 is where energetic electrons produce Bremsstrahlung radiation, with energies above the nucleon binding energy (E≈5.5MeV). This radiation induce (γ,n) and (e,e’n) reactions mainly in the natural tungsten target material (its total photoneutron cross section is about 4000 mb in a energy range from 9-17 MeV). These reactions may occur also in other components of the system (e.g. multi leaf collimator). During radiation treatment the human body may receive an additional dose inside and outside the treated volume produced by the mentioned nuclear reactions. We measured the neutron density at the treatment table using nuclear track detectors (PADC-NTD). These covered by a boron-converter are employed, including a cadmium filter, to determine the ratio between two groups of neutron energy, i.e. thermal and epithermal. The PADC-NTD detectors were exposed to the radiation field at the iso-center during regular operation of the accelerator. Neutron are determined indirectly by the converting reaction {sup 10}B(n,α){sup 7}Li the emerging charged particle leave their kinetic energy in the PADC forming a latent nuclear track, enlarged by chemical etching (6N, NaOH, 70°C). Track density provides information on the neutron density through calibration coefficient (∼1.6 10{sup 4} neutrons /track) obtained by a californium source. We report the estimation of the thermal and epithermal neutron field and its gradient for photoneutrons produced in radiotherapy treatments with 18 MV linear accelerators. It was obsered that photoneutron production have higher rate at the iso-center.

  6. RNA Aptamer Binds Heparin-Binding Epidermal Growth Factor-Like Growth Factor with High Affinity and Specificity and Neutralizes Its Activity

    Directory of Open Access Journals (Sweden)

    Masaki Yamato

    2017-09-01

    Conclusion: We identified a novel RNA aptamer that bound with high affinity and specificity to rhHB-EGF and potently inhibited the rhHB-EGF-mediated phosphorylation of EGFR. The anti-HB-EGF aptamer may be a promising therapeutic agent for specifically neutralizing HB-EGF signaling.

  7. CO2-Neutral Fuels

    NARCIS (Netherlands)

    Goede, A.; van de Sanden, M. C. M.

    2016-01-01

    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

  8. 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…

  9. Synthesis and electronic structure of cationic, neutral, and anionic bis(imino)pyridine iron alkyl complexes: evaluation of redox activity in single-component ethylene polymerization catalysts.

    Science.gov (United States)

    Tondreau, Aaron M; Milsmann, Carsten; Patrick, Andrew D; Hoyt, Helen M; Lobkovsky, Emil; Wieghardt, Karl; Chirik, Paul J

    2010-10-27

    A family of cationic, neutral, and anionic bis(imino)pyridine iron alkyl complexes has been prepared, and their electronic and molecular structures have been established by a combination of X-ray diffraction, Mössbauer spectroscopy, magnetochemistry, and open-shell density functional theory. For the cationic complexes, [((iPr)PDI)Fe-R][BPh(4)] ((iPr)PDI = 2,6-(2,6-(i)Pr(2)-C(6)H(3)N═CMe)(2)C(5)H(3)N; R = CH(2)SiMe(3), CH(2)CMe(3), or CH(3)), which are known single-component ethylene polymerization catalysts, the data establish high spin ferrous compounds (S(Fe) = 2) with neutral, redox-innocent bis(imino)pyridine chelates. One-electron reduction to the corresponding neutral alkyls, ((iPr)PDI)Fe(CH(2)SiMe(3)) or ((iPr)PDI)Fe(CH(2)CMe(3)), is chelate-based, resulting in a bis(imino)pyridine radical anion (S(PDI) = 1/2) antiferromagnetically coupled to a high spin ferrous ion (S(Fe) = 2). The neutral neopentyl derivative was reduced by an additional electron and furnished the corresponding anion, [Li(Et(2)O)(3)][((iPr)PDI)Fe(CH(2)CMe(3))N(2)], with concomitant coordination of dinitrogen. The experimental and computational data establish that this S = 0 compound is best described as a low spin ferrous compound (S(Fe) = 0) with a closed-shell singlet bis(imino)pyridine dianion (S(PDI) = 0), demonstrating that the reduction is ligand-based. The change in field strength of the bis(imino)pyridine coupled with the placement of the alkyl ligand into the apical position of the molecule induced a spin state change at the iron center from high to low spin. The relevance of the compounds and their electronic structures to olefin polymerization catalysis is also presented.

  10. The origin of Ag-Au-S-Se minerals in adularia-sericite epithermal deposits: constraints from the Broken Hills deposit, Hauraki Goldfield, New Zealand

    Science.gov (United States)

    Cocker, Helen A.; Mauk, Jeffrey L.; Rabone, Stuart D. C.

    2013-02-01

    The 7.1 Ma Broken Hills adularia-sericite Au-Ag deposit is currently the only producing rhyolite-hosted epithermal deposit in the Hauraki Goldfield of New Zealand. The opaque minerals include pyrite, electrum, acanthite (Ag2S), sphalerite, and galena, which are common in other adularia-sericite epithermal deposits in the Hauraki Goldfield and elsewhere worldwide. Broken Hills ores also contain the less common minerals aguilarite (Ag4SeS), naumannite (Ag2Se), petrovskaite (AuAgS), uytenbogaardtite (Ag3AuS2), fischesserite (Ag3AuSe2), an unnamed silver chloride (Ag2Cl), and unnamed Ag ± Au minerals. Uytenbogaardtite and petrovskaite occur with high-fineness electrum. Broken Hills is the only deposit in the Hauraki Goldfield where uytenbogaardtite and petrovskaite have been identified, and these phases appear to have formed predominantly from unmixing of a precursor high-temperature phase under hypogene conditions. Supergene minerals include covellite, chalcocite, Au-rich electrum, barite, and a variety of iron oxyhydroxide minerals. Uytenbogaardtite can form under supergene and hypogene conditions, and textural relationships between uytenbogaardtite and associated high-fineness electrum may be similar in both conditions. Distinguishing the likely environment of formation rests principally on identification of other supergene minerals and documenting their relationships with uytenbogaardtite. The presence of aguilarite, naumannite, petrovskaite, and fischesserite at Broken Hills reflects a Se-rich mineral assemblage. In the Hauraki Goldfield and the western Great Basin, USA, Se-rich minerals are more abundant in provinces that are characterized by bimodal rhyolite-andesite volcanism, but in other epithermal provinces worldwide, the controls on the occurrences of Se-bearing minerals remain poorly constrained, in spite of the unusually high grades associated with many Se-rich epithermal deposits.

  11. 8-group relative delayed neutron yields for epithermal neutron induced fission of sup 2 sup 3 sup 5 U and sup 2 sup 3 sup 9 Pu

    CERN Document Server

    Piksaikin, V M; Kazakov, L E; Korolev, G G; Roshchenko, V A; Tertychnyj, R G

    2001-01-01

    An 8-group representation of relative delayed neutron yields was obtained for epithermal neutron induced fission of sup 2 sup 3 sup 5 U and sup 2 sup 3 sup 9 Pu. These data were compared with ENDF/B-VI data in terms of the average half- life of the delayed neutron precursors and on the basis of the dependence of reactivity on the asymptotic period.

  12. Noble gas data from Goldfield and Tonopah epithermal Au-Ag deposits, ancestral Cascades Arc, USA: Evidence for a primitive mantle volatile source

    Science.gov (United States)

    Manning, Andrew H.; Hofstra, Albert H.

    2017-01-01

    The He, Ne, and Ar isotopic composition of fluid inclusions in ore and gangue minerals were analyzed to determine the source of volatiles in the high-grade Goldfield and Tonopah epithermal Au-Ag deposits in southwestern Nevada, USA. Ar and Ne are mainly atmospheric, whereas He has only a minor atmospheric component. Corrected 3He/4He ratios (with atmospheric He removed) range widely from 0.05 to 35.8 times the air 3He/4He ratio (RA), with a median of 1.43 RA. Forty-one percent of measured 3He/4He ratios are ≥4 RA, corresponding to ≥50% mantle He assuming a mantle ratio of 8 RA. These results suggest that mafic magmas were part of the magmatic-hydrothermal system underlying Goldfield and Tonopah, and that associated mantle-sourced volatiles may have played a role in ore formation. The three highest corrected 3He/4He ratios of 17.0, 23.7, and 35.8 RAindicate a primitive mantle He source and are the highest yet reported for any epithermal-porphyry system and for the Cascades arc region. Compiled 3He/4He measurements from epithermal-porphyry systems in subduction-related magmatic arcs around the world (n = 209) display a statistically significant correlation between 3He/4He and Au-Ag grade. The correlation suggests that conditions which promote higher fluid inclusion 3He/4He ratios (abundance of mantle volatiles and focused upward volatile transport) have some relation to conditions that promote higher Au-Ag grades (focused flow of metal-bearing fluids and efficient chemical traps). Results of this and previous investigations of He isotopes in epithermal-porphyry systems are consistent with the hypothesis posed in recent studies that mafic magmas serve an important function in the formation of these deposits.

  13. 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...... the paradigm”. This notion was presented at a series of lectures at Collège de France in 1977. Through a reading of Barthes’s autobiography, Roland Barthes par Roland Barthes (1975), the article demonstrates how Barthes in this text tries to outplay the paradigms that rules over the hegemonic understanding...... of gender and sexuality; also the fragmented text presents a vision of a sexual utopia, a neutral sexuality, that tries – like the queer theory – to go and think beyond a binary conception of gender and sexuality. Finally, it is suggested that we should start to think about a movement of “French queer...

  14. In vitro biological effectiveness of JRR-4 epithermal neutron beam. Experiment under free air beam and in water phantom. Cooperative research

    CERN Document Server

    Yamamoto, T; Horiguchi, Y; Kishi, T; Kumada, H; Matsumura, A; Nose, T; Torii, Y; Yamamoto, K

    2002-01-01

    The surviving curve and the biological effectiveness factor of dose components generated in boron neutron capture therapy (BNCT) were separately determined in neutron beams at Japan Research Reactor No.4. Surviving fraction of V79 Chinese hamster cell with or without sup 1 sup 0 B was obtained using an epithermal neutron beam (ENB), a mixed thermal-epithermal neutron beam (TNB-1), and a thermal neutron beam (TNB-2), which were used or planned to use for BNCT clinical trial. The cell killing effect of these neutron beams with or without the presence of sup 1 sup 0 B depended highly on the neutron beam used, according to the epithermal and fast neutron content in the beam. The biological effectiveness factor values of the boron capture reaction for ENB, TNB-1 and TNB-2 were 3.99+-0.24, 3.04+-0.19 and 1.43+-0.08, respectively. The biological effectiveness factor values of the high-LET dose components based on the hydrogen recoils and the nitrogen capture reaction were 2.50+-0.32, 2.34+-0.30 and 2.17+-0.28 for EN...

  15. 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.

  16. Exercise Equipment: Neutral Buoyancy

    Science.gov (United States)

    Shackelford, Linda; Valle, Paul

    2016-01-01

    Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

  17. Radiation injury of boron neutron capture therapy using mixed epithermal- and thermal neutron beams in patients with malignant glioma

    Energy Technology Data Exchange (ETDEWEB)

    Kageji, T. E-mail: kageji@clin.med.tokushima-u.ac.jp; Nagahiro, S.; Mizobuchi, Y.; Toi, H.; Nakagawa, Y.; Kumada, H

    2004-11-01

    The purpose of this study was to clarify the radiation injury in acute or delayed stage after boron neutron capture therapy (BNCT) using mixed epithermal- and thermal neutron beams in patients with malignant glioma. Eighteen patients with malignant glioma underwent mixed epithermal- and thermal neutron beam and sodium borocaptate between 1998 and 2004. The radiation dose (i.e. physical dose of boron n-alpha reaction) in the protocol used between 1998 and 2000 (Protocol A, n=8) prescribed a maximum tumor volume dose of 15 Gy. In 2001, a new dose-escalated protocol was introduced (Protocol B, n=4); it prescribes a minimum tumor volume dose of 18 Gy or, alternatively, a minimum target volume dose of 15 Gy. Since 2002, the radiation dose was reduced to 80-90% dose of Protocol B because of acute radiation injury. A new Protocol was applied to 6 glioblastoma patients (Protocol C, n=6). The average values of the maximum vascular dose of brain surface in Protocol A, B and C were 11.4{+-}4.2 Gy, 15.7{+-}1.2 and 13.9{+-}3.6 Gy, respectively. Acute radiation injury such as a generalized convulsion within 1 week after BNCT was recognized in three patients of Protocol B. Delayed radiation injury such as a neurological deterioration appeared 3-6 months after BNCT, and it was recognized in 1 patient in Protocol A, 5 patients in Protocol B. According to acute radiation injury, the maximum vascular dose was 15.8{+-}1.3 Gy in positive and was 12.6{+-}4.3 Gy in negative. There was no significant difference between them. According to the delayed radiation injury, the maximum vascular dose was 13.8{+-}3.8 Gy in positive and was 13.6{+-}4.9 Gy in negative. There was no significant difference between them. The dose escalation is limited because most patients in Protocol B suffered from acute radiation injury. We conclude that the maximum vascular dose does not exceed over 12 Gy to avoid the delayed radiation injury, especially, it should be limited under 10 Gy in the case that tumor

  18. Characteristics of HPV-specific antibody responses induced by infection and vaccination: cross-reactivity, neutralizing activity, avidity and IgG subclasses.

    Science.gov (United States)

    Scherpenisse, Mirte; Schepp, Rutger M; Mollers, Madelief; Meijer, Chris J L M; Berbers, Guy A M; van der Klis, Fiona R M

    2013-01-01

    In order to assess HPV-specific IgG characteristics, we evaluated multiple aspects of the humoral antibody response that will provide insight in the HPV humoral immune response induced by HPV infection and vaccination. Cross-reactivity of HPV-specific antibodies induced by infection or vaccination was assessed with VLP16 or 18 inhibition using a VLP-based multiplex immunoassay (MIA) for HPV16, 18, 31, 33, 45, 52 and 58. HPV16/18 specific IgG1-4 subclasses and avidity were determined with the VLP-MIA in sera after HPV infection and after vaccination. Neutralizing antibodies were determined in a small subset of single-seropositive and multi-seropositive naturally derived antibodies. Naturally derived antibodies from single-positive sera were highly genotype-specific as homologue VLP-inhibition percentages varied between 78-94%. In multi-positive sera, cross-reactive antibodies were observed both within and between α7 and α9 species. After vaccination, cross-reactive antibodies were mainly species-specific. Avidity of vaccine-derived HPV-specific antibodies was 3 times higher than that of antibodies induced by HPV infection (pHPV infection and vaccination. In the small subset tested, the number of single-positive sera with neutralizing capacity was higher than of multi-positive sera. Naturally derived HPV-specific antibodies from single-positive samples showed different characteristics in terms of cross-reactivity and neutralizing capacity compared with antibodies from multi-positive sera. Post-vaccination, HPV antibody avidity was approximately 3 times higher than antibody avidity induced by HPV infection. Therefore, antibody avidity might be a potential surrogate of protection.

  19. Characteristics of HPV-specific antibody responses induced by infection and vaccination: cross-reactivity, neutralizing activity, avidity and IgG subclasses.

    Directory of Open Access Journals (Sweden)

    Mirte Scherpenisse

    Full Text Available OBJECTIVES: In order to assess HPV-specific IgG characteristics, we evaluated multiple aspects of the humoral antibody response that will provide insight in the HPV humoral immune response induced by HPV infection and vaccination. METHODS: Cross-reactivity of HPV-specific antibodies induced by infection or vaccination was assessed with VLP16 or 18 inhibition using a VLP-based multiplex immunoassay (MIA for HPV16, 18, 31, 33, 45, 52 and 58. HPV16/18 specific IgG1-4 subclasses and avidity were determined with the VLP-MIA in sera after HPV infection and after vaccination. Neutralizing antibodies were determined in a small subset of single-seropositive and multi-seropositive naturally derived antibodies. RESULTS: Naturally derived antibodies from single-positive sera were highly genotype-specific as homologue VLP-inhibition percentages varied between 78-94%. In multi-positive sera, cross-reactive antibodies were observed both within and between α7 and α9 species. After vaccination, cross-reactive antibodies were mainly species-specific. Avidity of vaccine-derived HPV-specific antibodies was 3 times higher than that of antibodies induced by HPV infection (p<0.0001. IgG1 and IgG3 were found to be the predominant subclasses observed after HPV infection and vaccination. In the small subset tested, the number of single-positive sera with neutralizing capacity was higher than of multi-positive sera. CONCLUSION: Naturally derived HPV-specific antibodies from single-positive samples showed different characteristics in terms of cross-reactivity and neutralizing capacity compared with antibodies from multi-positive sera. Post-vaccination, HPV antibody avidity was approximately 3 times higher than antibody avidity induced by HPV infection. Therefore, antibody avidity might be a potential surrogate of protection.

  20. Wavelength feature mapping as a proxy to mineral chemistry for investigating geologic systems: An example from the Rodalquilar epithermal system

    Science.gov (United States)

    van der Meer, Freek; Kopačková, Veronika; Koucká, Lucie; van der Werff, Harald M. A.; van Ruitenbeek, Frank J. A.; Bakker, Wim H.

    2018-02-01

    The final product of a geologic remote sensing data analysis using multi spectral and hyperspectral images is a mineral (abundance) map. Multispectral data, such as ASTER, Landsat, SPOT, Sentinel-2, typically allow to determine qualitative estimates of what minerals are in a pixel, while hyperspectral data allow to quantify this. As input to most image classification or spectral processing approach, endmembers are required. An alternative approach to classification is to derive absorption feature characteristics such as the wavelength position of the deepest absorption, depth of the absorption and symmetry of the absorption feature from hyperspectral data. Two approaches are presented, tested and compared in this paper: the 'Wavelength Mapper' and the 'QuanTools'. Although these algorithms use a different mathematical solution to derive absorption feature wavelength and depth, and use different image post-processing, the results are consistent, comparable and reproducible. The wavelength images can be directly linked to mineral type and abundance, but more importantly also to mineral chemical composition and subtle changes thereof. This in turn allows to interpret hyperspectral data in terms of mineral chemistry changes which is a proxy to pressure-temperature of formation of minerals. We show the case of the Rodalquilar epithermal system of the southern Spanish Gabo de Gata volcanic area using HyMAP airborne hyperspectral images.

  1. Gold-Silver mineralization in porphyry-epithermal systems of the Baimka trend, western Chukchi Peninsula, Russia

    Science.gov (United States)

    Nikolaev, Yu. N.; Baksheev, I. A.; Prokofiev, V. Yu.; Nagornaya, E. V.; Marushchenko, L. I.; Sidorina, Yu. N.; Chitalin, A. F.; Kal'ko, I. A.

    2016-07-01

    Mineralogical, fluid inclusion, and geochemical studies of precious metal mineralization within the Baimka trend in the western Chukchi Peninsula have been preformed. Porphyry copper-molybdenum-gold deposits and prospects of the Baimka trend are spatially related to monzonitic rocks of the Early Cretaceous Egdygkych Complex. Four types of precious metal-bearing assemblages have been identified: (1) chalcopyrite + bornite + quartz with high-fineness native gold enclosed in bornite, (2) low-Mn dolomite + quartz + sulfide (chalcopyrite, sphalerite, galena, tennantite-tetrahedrite) ± tourmaline with low-fineness native gold and hessite, (3) rhodochrosite + high-Mn dolomite + quartz + sulfide (chalcopyrite, sphalerite, galena, tennantite- tetrahedrite) with low-fineness native gold, electrum, acanthite, Ag and Au-Ag tellurides, and Ag sulfosalts, and (4) calcite + quartz + sulfide (chalcopyrite, sphalerite, galena) with low-fineness native gold, Ag sulfides and selenides, and Ag-bearing sulfosalts. Study of fluid inclusions from quartz, sphalerite, and fluorite have revealed that hydrothermal ores within the Baimka trend precipitated from fluids with strongly variable salinity at temperatures and pressures ranging from 594 to 104°C and from 1200 to 170 bar, respectively. An indicator of vertical AgPbZn/CuBiMo geochemical zoning is proposed. The value range of this indicator makes it possible to estimate the erosion level of the porphyry-epithermal system. The erosion level of the Baimka deposits and prospects deepens in the following order: Vesenny deposit → Pryamoi prospect → Nakhodka prospect → Peschanka deposit → III Vesenny prospect.

  2. IER-297 CED-2: Final Design for Thermal/Epithermal eXperiments with Jemima Plates with Polyethylene and Hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Percher, C. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zywiec, W. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Heinrichs, D. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2018-01-11

    This report presents the final design (CED-2) for IER-297, and focuses on 15 critical configurations using highly enriched uranium (HEU) Jemima plates moderated by polyethylene with and without hafnium diluent. The goal of the U.S. Nuclear Criticality Safety Program’s Thermal/Epithermal eXperiments (TEX) is to design and conduct new critical experiments to address high priority nuclear data needs from the nuclear criticality safety and nuclear data communities, with special emphasis on intermediate energy (0.625 eV – 100 keV) assemblies that can be easily modified to include various high priority diluent materials. The TEX (IER 184) CED-1 Report [1], completed in 2012, demonstrated the feasibility of meeting the TEX goals with two existing NCSP fissile assets, plutonium Zero Power Physics Reactor (ZPPR) plates and highly enriched uranium (HEU) Jemima plates. The first set of TEX experiments will focus on using the plutonium ZPPR plates with polyethylene moderator and tantalum diluents.

  3. Study on the Impact of Thermal Agitation on Doppler Coefficient in Epithermal Range for Gd-Bearing Fuel

    Directory of Open Access Journals (Sweden)

    Satoshi Takeda

    2016-01-01

    Full Text Available The impact of thermal agitation on Doppler coefficient for Gd-bearing fuel was analyzed. It was found through the analysis that the impact increases when a small amount of Gd2O3 is added to pure UO2 fuel although the impact decreases for a large amount of Gd2O3. This tendency was discussed with the usage of simplified expression for the difference of Doppler coefficient. The simplified expression was used to consider the tendency, and it was revealed that the tendency mainly comes from the rapid decrement of multiplication factor and the relatively slow decrement of the magnitude of sensitivity coefficient of U-238 capture cross section at low Gd2O3 concentration. Similar tendency which shows a maximum impact on Doppler coefficient at interior concentration is expected for other UO2 fuel with a slight content of strong absorber. This indicates that Doppler coefficient of UO2 fuel system with low content of strong absorber should be analyzed carefully by considering thermal agitation in epithermal range.

  4. Ultracold neutral plasmas

    Science.gov (United States)

    Lyon, M.; Rolston, S. L.

    2017-01-01

    By photoionizing samples of laser-cooled atoms with laser light tuned just above the ionization limit, plasmas can be created with electron and ion temperatures below 10 K. These ultracold neutral plasmas have extended the temperature bounds of plasma physics by two orders of magnitude. Table-top experiments, using many of the tools from atomic physics, allow for the study of plasma phenomena in this new regime with independent control over the density and temperature of the plasma through the excitation process. Characteristic of these systems is an inhomogeneous density profile, inherited from the density distribution of the laser-cooled neutral atom sample. Most work has dealt with unconfined plasmas in vacuum, which expand outward at velocities of order 100 m/s, governed by electron pressure, and with lifetimes of order 100 μs, limited by stray electric fields. Using detection of charged particles and optical detection techniques, a wide variety of properties and phenomena have been observed, including expansion dynamics, collective excitations in both the electrons and ions, and collisional properties. Through three-body recombination collisions, the plasmas rapidly form Rydberg atoms, and clouds of cold Rydberg atoms have been observed to spontaneously avalanche ionize to form plasmas. Of particular interest is the possibility of the formation of strongly coupled plasmas, where Coulomb forces dominate thermal motion and correlations become important. The strongest impediment to strong coupling is disorder-induced heating, a process in which Coulomb energy from an initially disordered sample is converted into thermal energy. This restricts electrons to a weakly coupled regime and leaves the ions barely within the strongly coupled regime. This review will give an overview of the field of ultracold neutral plasmas, from its inception in 1999 to current work, including efforts to increase strong coupling and effects on plasma properties due to strong coupling.

  5. Ultracold neutral plasmas.

    Science.gov (United States)

    Lyon, M; Rolston, S L

    2017-01-01

    By photoionizing samples of laser-cooled atoms with laser light tuned just above the ionization limit, plasmas can be created with electron and ion temperatures below 10 K. These ultracold neutral plasmas have extended the temperature bounds of plasma physics by two orders of magnitude. Table-top experiments, using many of the tools from atomic physics, allow for the study of plasma phenomena in this new regime with independent control over the density and temperature of the plasma through the excitation process. Characteristic of these systems is an inhomogeneous density profile, inherited from the density distribution of the laser-cooled neutral atom sample. Most work has dealt with unconfined plasmas in vacuum, which expand outward at velocities of order 100 m/s, governed by electron pressure, and with lifetimes of order 100 μs, limited by stray electric fields. Using detection of charged particles and optical detection techniques, a wide variety of properties and phenomena have been observed, including expansion dynamics, collective excitations in both the electrons and ions, and collisional properties. Through three-body recombination collisions, the plasmas rapidly form Rydberg atoms, and clouds of cold Rydberg atoms have been observed to spontaneously avalanche ionize to form plasmas. Of particular interest is the possibility of the formation of strongly coupled plasmas, where Coulomb forces dominate thermal motion and correlations become important. The strongest impediment to strong coupling is disorder-induced heating, a process in which Coulomb energy from an initially disordered sample is converted into thermal energy. This restricts electrons to a weakly coupled regime and leaves the ions barely within the strongly coupled regime. This review will give an overview of the field of ultracold neutral plasmas, from its inception in 1999 to current work, including efforts to increase strong coupling and effects on plasma properties due to strong coupling.

  6. Photoproduction of neutral pions

    OpenAIRE

    Fuhrer, Andreas

    2009-01-01

    The pion and nucleon mass differences generate a very pronounced cusp in the photoproduction reaction of a single neutral pion on the proton. A nonrelativistic effective field theory to describe this reaction is constructed. The approach is rigorous in the sense that it is an effective field theory with a consistent power counting scheme. Expressions for the S- and P-wave multipole amplitudes at one loop are given. The relation of the phase of the electric multipole E_0+ to the phase of the S...

  7. Geology of the epithermal Ag-Au Huevos Verdes vein system and San José district, Deseado massif, Patagonia, Argentina

    Science.gov (United States)

    Dietrich, Andreas; Gutierrez, Ronald; Nelson, Eric P.; Layer, Paul W.

    2012-03-01

    The San José district is located in the northwest part of the Deseado massif and hosts a number of epithermal Ag-Au quartz veins of intermediate sulfidation style, including the Huevos Verdes vein system. Veins are hosted by andesitic rocks of the Bajo Pobre Formation and locally by rhyodacitic pyroclastic rocks of the Chon Aike Formation. New 40Ar/39Ar constraints on the age of host rocks and mineralization define Late Jurassic ages of 151.3 ± 0.7 Ma to 144.7 ± 0.1 Ma for volcanic rocks of the Bajo Pobre Formation and of 147.6 ± 1.1 Ma for the Chon Aike Formation. Illite ages of the Huevos Verdes vein system of 140.8 ± 0.2 and 140.5 ± 0.3 Ma are 4 m.y. younger than the volcanic host rock unit. These age dates are among the youngest reported for Jurassic volcanism in the Deseado massif and correlate well with the regional context of magmatic and hydrothermal activity. The Huevos Verdes vein system has a strike length of 2,000 m, with several ore shoots along strike. The vein consists of a pre-ore stage and three main ore stages. Early barren quartz and chalcedony are followed by a mottled quartz stage of coarse saccharoidal quartz with irregular streaks and discontinuous bands of sulfide-rich material. The banded quartz-sulfide stage consists of sulfide-rich bands alternating with bands of quartz and bands of chlorite ± illite. Late-stage sulfide-rich veinlets are associated with kaolinite gangue. Ore minerals are argentite and electrum, together with pyrite, sphalerite, galena, chalcopyrite, minor bornite, covellite, and ruby silver. Wall rock alteration is characterized by narrow (220°C. Kaolinite occurring with the late sulfide-rich veinlet stage indicates pH 315°, whereas strike directions of <315° are predicted with an induced dextral strike-slip movement. The components of the structural model appear to be present on a regional scale and are not restricted to the San José district.

  8. Differential killing activity of cetylpyridinium chloride with or without bacto neutralizing buffer quench against firmly adhered Salmonella gaminara and Shigella sonnei on cut lettuce stored at 4 degrees C.

    Science.gov (United States)

    Osman, Moeznimanwaty; Janes, Marlene E; Story, Robert; Nannapaneni, Ramakrishna; Johnson, Michael G

    2006-06-01

    Cetylpyridinium chloride (CPC) activity was quenched with Bacto neutralizing buffer on inoculated cut iceberg lettuce. This protocol permitted comparison of the numbers of Salmonella Gaminara- or Shigella sonnei-inoculated cells on lettuce that survived 1 min of CPC treatment. Cut lettuce was inoculated with about 6 log of Salmonella or 9 log of Shigella and stored in Whirl-Pak bags at 4 degrees C for up to 4 days. Loosely adhered pathogen cells were washed off before CPC treatment. Firmly adhered cells of Salmonella Gaminara or S. sonnei on cut iceberg lettuce survived treatment with CPC even at the 0.4% CPC level if the CPC activity was quenched after 1 min by adding Bacto neutralizing buffer. The results confirm that there is extended killing activity of residual CPC against Salmonella Gaminara or S. sonnei if the residual CPC remaining in contact with the lettuce after the initial 1-min wash is not quenched. The CPC treatment was useful in reducing the numbers of these target pathogens on lettuce.

  9. Rabbits immunized with Epstein-Barr virus gH/gL or gB recombinant proteins elicit higher serum virus neutralizing activity than gp350.

    Science.gov (United States)

    Cui, Xinle; Cao, Zhouhong; Chen, Quanyi; Arjunaraja, Swadhinya; Snow, Andrew L; Snapper, Clifford M

    2016-07-25

    Epstein-Barr virus (EBV) is the primary cause of infectious mononucleosis and has been strongly implicated in the etiology of multiple epithelial and lymphoid cancers, such as nasopharyngeal carcinoma, gastric carcinoma, Hodgkin lymphoma, Burkitt lymphoma, non-Hodgkin lymphoma and post-transplant lymphoproliferative disorder. There is currently no licensed prophylactic vaccine for EBV. Most efforts to develop prophylactic vaccines have focused on EBV gp350, which binds to CD21/CD35 to gain entry into B cells, and is a major target of serum neutralizing antibody in EBV seropositive humans. However, a recombinant monomeric gp350 protein failed to prevent EBV infection in a phase II clinical trial. Thus, alternative or additional target antigens may be necessary for a successful prophylactic vaccine. EBV gH/gL and gB proteins coordinately mediate EBV fusion and entry into B cells and epithelial cells, strongly suggesting that vaccination with these proteins might elicit antibodies that will prevent EBV infection. We produced recombinant trimeric and monomeric EBV gH/gL heterodimeric proteins and a trimeric EBV gB protein, in addition to tetrameric and monomeric gp350(1-470) proteins, in Chinese hamster ovary cells. We demonstrated that vaccination of rabbits with trimeric and monomeric gH/gL, trimeric gB, and tetrameric gp350(1-470) induced serum EBV-neutralizing titers, using cultured human B cells, that were >100-fold, 20-fold, 18-fold, and 4-fold higher, respectively, than monomeric gp350(1-470). These data strongly suggest a role for testing EBV gH/gL and EBV gB in a future prophylactic vaccine to prevent EBV infection of B cells, as well as epithelial cells. Published by Elsevier Ltd.

  10. Rapid detection of anti-Vaccinia virus neutralizing antibodies

    Directory of Open Access Journals (Sweden)

    Lichtfuss Gregor F

    2011-03-01

    Full Text Available Abstract Increasing infections with Monkeypox and Cowpox viruses pose a continuous and growing threat to human health. The standard method for detecting poxvirus neutralizing antibodies is the plaque-reduction neutralization test that is specific but also time-consuming and laborious. Therefore, a rapid and reliable method was developed to determine neutralizing antibody titers within twelve hours. The new assay measures viral mRNA transcription as a marker for actively replicating virus after incomplete neutralization using real-time PCR.

  11. Epithermal mineralization and ore controls of the Shasta Au-Ag deposit, Toodoggone District, British Columbia, Canada

    Science.gov (United States)

    Thiersch, P. C.; Williams-Jones, A. E.; Clark, J. R.

    1997-01-01

    The Shasta gold-silver deposit, British Columbia, Canada, is an adularia-sericite-type epithermal deposit in which deposition of precious metals coincided with the transition of quartz- to calcite-dominant gangue. Mineralization is associated with stockwork-breccia zones in potassically altered dacitic lapilli tuffs and flows, and consists of pyrite, sphalerite, chalcopyrite, galena, acanthite, electrum and native silver. Pre- and post-ore veins consist solely of quartz and calcite, respectively. Fluid inclusion microthermometry indicates that ore minerals were deposited between 280 ° and 225 °C, from a relatively dilute hydrothermal fluid (˜1.5 wt.% NaCl equivalent). Abundant vapor-rich inclusions in ore-stage calcite are consistent with boiling. Oxygen and hydrogen isotopic data (δ18Ofluid = -1.5 to -4.1‰; δDfluid = -148 to -171‰) suggest that the fluid had a meteoric origin, but was 18O-enriched by interaction with volcanic wallrocks. Initial (˜280 °C) fluid pH and log f O2 conditions are estimated at 5.3 to 6.0, and -32.5 to -33 bar, respectively; during ore deposition, the fluid became more alkaline and oxidizing. Ore deposition at Shasta is attributed to localization of meteoric hydrothermal fluids by extensional faults; mineralization was controlled by boiling in response to hydraulic brecciation. Calcite and base metal sulfides precipitated due to the increase in pH that accompanied boiling, and the associated decrease in H2S concentration led to precipitation of gold and silver.

  12. Retinol binding protein and vitamin D associations with serum antibody isotypes, serum influenza virus-specific neutralizing activities and airway cytokine profiles.

    Science.gov (United States)

    Jones, B G; Oshansky, C M; Bajracharya, R; Tang, L; Sun, Y; Wong, S S; Webby, R; Thomas, P G; Hurwitz, J L

    2016-02-01

    Vitamin A supports the induction of immunoglobulin (Ig)A responses at mucosal surfaces in mice, but much less is known about the influence of vitamins on antibody isotype expression in humans. To address this knowledge gap, we examined 46 residual blood samples from adults and children, some of whom were experiencing influenza virus infections of the respiratory tract. Assays were performed for retinol binding protein (RBP, a surrogate for vitamin A), vitamin D (a related vitamin) and antibody isotypes. Results showed that all but two tested samples exhibited RBP and/or vitamin D insufficiencies or deficiencies. Vitamin D correlated with blood IgM and IgG3, while RBP correlated with IgG4 and IgA. RBP also correlated positively with age and with influenza virus-specific antibody neutralization titres. Individuals with low blood RBP levels exhibited the highest frequencies of over-expressed cytokines and growth factors in nasal wash samples, an indication of inflamed mucosal tissues. While cause-effect relationships were not discerned, results support a hypothesis that vitamins directly influence B cell isotype expression in humans, and by so doing may help protect mucosal surfaces from respiratory viral disease. © 2015 British Society for Immunology.

  13. A new balancing three level three dimensional space vector modulation strategy for three level neutral point clamped four leg inverter based shunt active power filter controlling by nonlinear back stepping controllers.

    Science.gov (United States)

    Chebabhi, Ali; Fellah, Mohammed Karim; Kessal, Abdelhalim; Benkhoris, Mohamed F

    2016-07-01

    In this paper is proposed a new balancing three-level three dimensional space vector modulation (B3L-3DSVM) strategy which uses a redundant voltage vectors to realize precise control and high-performance for a three phase three-level four-leg neutral point clamped (NPC) inverter based Shunt Active Power Filter (SAPF) for eliminate the source currents harmonics, reduce the magnitude of neutral wire current (eliminate the zero-sequence current produced by single-phase nonlinear loads), and to compensate the reactive power in the three-phase four-wire electrical networks. This strategy is proposed in order to gate switching pulses generation, dc bus voltage capacitors balancing (conserve equal voltage of the two dc bus capacitors), and to switching frequency reduced and fixed of inverter switches in same times. A Nonlinear Back Stepping Controllers (NBSC) are used for regulated the dc bus voltage capacitors and the SAPF injected currents to robustness, stabilizing the system and to improve the response and to eliminate the overshoot and undershoot of traditional PI (Proportional-Integral). Conventional three-level three dimensional space vector modulation (C3L-3DSVM) and B3L-3DSVM are calculated and compared in terms of error between the two dc bus voltage capacitors, SAPF output voltages and THDv, THDi of source currents, magnitude of source neutral wire current, and the reactive power compensation under unbalanced single phase nonlinear loads. The success, robustness, and the effectiveness of the proposed control strategies are demonstrated through simulation using Sim Power Systems and S-Function of MATLAB/SIMULINK. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  14. In vitro biological effectiveness of JRR-4 epithermal neutron beam. Experiment under free air beam and in water phantom. Cooperative research

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Tetsuya; Matsumura, Akira; Nose, Tadao [Tsukuba Univ., Tsukuba, Ibaraki (Japan); Yamamoto, Kazuyoshi; Kumada, Hiroaki; Kishi, Toshiaki; Hori, Naohiko; Torii, Yoshiya; Horiguchi, Yoji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2002-05-01

    The surviving curve and the biological effectiveness factor of dose components generated in boron neutron capture therapy (BNCT) were separately determined in neutron beams at Japan Research Reactor No.4. Surviving fraction of V79 Chinese hamster cell with or without {sup 10}B was obtained using an epithermal neutron beam (ENB), a mixed thermal-epithermal neutron beam (TNB-1), and a thermal neutron beam (TNB-2), which were used or planned to use for BNCT clinical trial. The cell killing effect of these neutron beams with or without the presence of {sup 10}B depended highly on the neutron beam used, according to the epithermal and fast neutron content in the beam. The biological effectiveness factor values of the boron capture reaction for ENB, TNB-1 and TNB-2 were 3.99{+-}0.24, 3.04{+-}0.19 and 1.43{+-}0.08, respectively. The biological effectiveness factor values of the high-LET dose components based on the hydrogen recoils and the nitrogen capture reaction were 2.50{+-}0.32, 2.34{+-}0.30 and 2.17{+-}0.28 for ENB, TNB-1 and TNB-2, respectively. The biological effectiveness factor values of the neutron and photon components were 1.22{+-}0.16, 1.23{+-}0.16 and 1.21{+-}0.16, respectively. The depth function of biological effectiveness factor in water phantom and the difference in biological effectiveness factor among boron compounds were also determined. The experimental determination of biological effectiveness factor outlined in this paper is applicable to the dose calculation for each dose component of the neutron beams and contribute to an accurate biological effectiveness factor as comparison with a neutron beam at a different facility employed in ongoing and planned BNCT clinical trials. (author)

  15. Fast Outflows of Neutral Hydrogen in Radio Galaxies

    NARCIS (Netherlands)

    Oosterloo, T. A.; Morganti, R.; Emonts, B. H. C.; Tadhunter, C. N.

    2004-01-01

    Abstract: AGN activity is known to drive fast outflows of gas. We report the discovery of fast outflows of neutral gas with velocities over 1000 km/s in a number of radio galaxies. In the best studied object, 3C~293, the kinematical properties of the neutral and ionised outflows are similar,

  16. The improvement of the energy resolution in epi-thermal neutron region of Bonner sphere using boric acid water solution moderator.

    Science.gov (United States)

    Ueda, H; Tanaka, H; Sakurai, Y

    2015-10-01

    Bonner sphere is useful to evaluate the neutron spectrum in detail. We are improving the energy resolution in epi-thermal neutron region of Bonner sphere, using boric acid water solution as a moderator. Its response function peak is narrower than that for polyethylene moderator and the improvement of the resolution is expected. The resolutions between polyethylene moderator and boric acid water solution moderator were compared by simulation calculation. Also the influence in the uncertainty of Bonner sphere configuration to spectrum estimation was simulated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. 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

  18. 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

  19. Metal-ion mutagenesis: conversion of a purple acid phosphatase from sweet potato to a neutral phosphatase with the formation of an unprecedented catalytically competent Mn(II)Mn(II) active site.

    Science.gov (United States)

    Mitić, Natasa; Noble, Christopher J; Gahan, Lawrence R; Hanson, Graeme R; Schenk, Gerhard

    2009-06-17

    The currently accepted paradigm is that the purple acid phosphatases (PAPs) require a heterovalent, dinuclear metal-ion center for catalysis. It is believed that this is an essential feature for these enzymes in order for them to operate under acidic conditions. A PAP from sweet potato is unusual in that it appears to have a specific requirement for manganese, forming a unique Fe(III)-mu-(O)-Mn(II) center under catalytically optimal conditions (Schenk et al. Proc. Natl. Acad. Sci. U.S.A. 2005, 102, 273). Herein, we demonstrate, with detailed electron paramagnetic resonance (EPR) spectroscopic and kinetic studies, that in this enzyme the chromophoric Fe(III) can be replaced by Mn(II), forming a catalytically active, unprecedented antiferromagnetically coupled homodivalent Mn(II)-mu-(H)OH-mu-carboxylato-Mn(II) center in a PAP. However, although the enzyme is still active, it no longer functions as an acid phosphatase, having optimal activity at neutral pH. Thus, PAPs may have evolved from distantly related divalent dinuclear metallohydrolases that operate under pH neutral conditions by stabilization of a trivalent-divalent metal-ion core. The present Mn(II)-Mn(II) system models these distant relatives, and the results herein make a significant contribution to our understanding of the role of the chromophoric metal ion as an activator of the nucleophile. In addition, the detailed analysis of strain broadened EPR spectra from exchange-coupled dinuclear Mn(II)-Mn(II) centers described herein provides the basis for the full interpretation of the EPR spectra from other dinuclear Mn metalloenzymes.

  20. An ERBB1-3 Neutralizing Antibody Mixture With High Activity Against Drug-Resistant HER2+ Breast Cancers With ERBB Ligand Overexpression.

    Science.gov (United States)

    Schwarz, Luis J; Hutchinson, Katherine E; Rexer, Brent N; Estrada, Mónica Valeria; Gonzalez Ericsson, Paula I; Sanders, Melinda E; Dugger, Teresa C; Formisano, Luigi; Guerrero-Zotano, Angel; Red-Brewer, Monica; Young, Christian D; Lantto, Johan; Pedersen, Mikkel W; Kragh, Michael; Horak, Ivan D; Arteaga, Carlos L

    2017-11-01

    Plasticity of the ERBB receptor network has been suggested to cause acquired resistance to anti-human epidermal growth factor receptor 2 (HER2) therapies. Thus, we studied whether a novel approach using an ERBB1-3-neutralizing antibody mixture can block these compensatory mechanisms of resistance. HER2+ cell lines and xenografts (n ≥ 6 mice per group) were treated with the ERBB1-3 antibody mixture Pan-HER, trastuzumab/lapatinib (TL), trastuzumab/pertuzumab (TP), or T-DM1. Downregulation of ERBB receptors was assessed by immunoblot analysis and immunohistochemistry. Paired pre- and post-T-DM1 tumor biopsies from patients (n = 11) with HER2-amplified breast cancer were evaluated for HER2 and P-HER3 expression by immunohistochemistry and/or fluorescence in situ hybridization. ERBB ligands were measured by quantitative reverse transcription polymerase chain reaction. Drug-resistant cells were generated by chronic treatment with T-DM1. All statistical tests were two-sided. Treatment with Pan-HER inhibited growth and promoted degradation of ERBB1-3 receptors in a panel of HER2+ breast cancer cells. Compared with TL, TP, and T-DM1, Pan-HER induced a similar antitumor effect against established BT474 and HCC1954 tumors, but was superior to TL against MDA-361 xenografts (TL mean = 2026 mm 3 , SD = 924 mm 3 , vs Pan-HER mean = 565 mm 3 , SD = 499 mm 3 , P = .04). Pan-HER-treated BT474 xenografts did not recur after treatment discontinuation, whereas tumors treated with TL, TP, and T-DM1 did. Post-TP and post-T-DM1 recurrent tumors expressed higher levels of neuregulin-1 (NRG1), HER3 and P-HER3 (all P < .05). Higher levels of P-HER3 protein and NRG1 mRNA were also observed in HER2+ breast cancers progressing after T-DM1 and trastuzumab (NRG1 transcript fold change ± SD; pretreatment = 2, SD = 1.9, vs post-treatment = 11.4, SD = 10.3, P = .04). The HER3-neutralizing antibody LJM716 resensitized the drug-resistant cells to T-DM1, suggesting a

  1. Neutral evolution of mutational robustness.

    NARCIS (Netherlands)

    Nimwegen, E. van; Crutchfield, J.P.; Huynen, M.A.

    1999-01-01

    We introduce and analyze a general model of a population evolving over a network of selectively neutral genotypes. We show that the population's limit distribution on the neutral network is solely determined by the network topology and given by the principal eigenvector of the network's adjacency

  2. The merits of neutral theory

    NARCIS (Netherlands)

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

    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

  3. The merits of neutral theory

    NARCIS (Netherlands)

    Alonso, D.; Etienne, R.S.; McKane, A.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

  4. Net neutrality and audiovisual services

    NARCIS (Netherlands)

    van Eijk, N.; Nikoltchev, S.

    2011-01-01

    Net neutrality is high on the European agenda. New regulations for the communication sector provide a legal framework for net neutrality and need to be implemented on both a European and a national level. The key element is not just about blocking or slowing down traffic across communication

  5. Neutral point detection by satellites. [magnetospheric neutral sheets

    Science.gov (United States)

    Schindler, K.; Ness, N. F.

    1974-01-01

    The concept of a neutral point depends on the physical phenomena described. The regions with B less than about 1 gamma detected by Schindler and Ness may be interpreted as neutral regions for the ion-tearing process. The assumption of the presence of a multiple neutral point structure (with temporal variations) is still the most promising interpretation of the Explorer 34 data. Alternatives suggested by Russell lead to difficulties. Nevertheless, the final answer can come only from multiple satellite systems. A 1-day displacement of the day count in the data discussed by Schindler and Ness is corrected.

  6. Liberal Neutrality : Constructivist, not foundationalist

    Directory of Open Access Journals (Sweden)

    Lendell Horne

    2009-06-01

    Full Text Available In defending the principle of neutrality, liberals have often appealed to a more general moral principle that forbids coercing persons in the name of reasons those persons themselves cannot reasonably be expected to share. Yet liberals have struggled to articulate a non-arbitrary, non-dogmatic distinction between the reasons that persons can reasonably be expected to share and those they cannot. The reason for this, I argue, is that what it means to “share a reason” is itself obscure. In this paper I articulate two different conceptions of what it is to share a reason; I call these conceptions “foundationalist” and “constructivist.” On the foundationalist view, two people “share” a reason just in the sense that the same reason applies to each of them independently. On this view, I argue, debates about the reasons we share collapse into debates about the reasons we have, moving us no closer to an adequate defense of neutrality. On the constructivist view, by contrast, “sharing reasons” is understood as a kind of activity, and the reasons we must share are just those reasons that make this activity possible. I argue that the constructivist conception of sharing reasons yields a better defense of the principle of neutrality. À travers leur défense du principe de neutralité, les libéraux ont souvent interpellé un principe moral plus général qui interdit de contraindre des personnes pour des raisons dont on ne peut raisonnablement attendre que ces personnes elles-mêmes les partagent. Les libéraux éprouvent cependant de la difficulté à articuler une distinction non-arbitraire et non-dogmatique entre les raisons dont on peut raisonnablement attendre que les personnes les partagent et celles dont on ne le peut pas. Je soutiens dans cet article que cette difficulté provient du fait que «partager une raison » est une notion obscure. Pour illustrer cela, je me pencherai sur deux conceptions distinctes de ce que veut dire

  7. Geodynamics and metallogeny of the central Eurasian porphyry and related epithermal mineral systems: A review

    Science.gov (United States)

    Seltmann, Reimar; Porter, T. Mike; Pirajno, Franco

    2014-01-01

    continued to develop, both the Sakmara and Khanty-Mansi back-arc basins were closed and the collage of cratons and arcs were sutured by accretionary complexes. During the Permian and Triassic, the North China craton approached and docked with the continent, closing the Mongol-Okhotsk Sea, an embayment on the Palaeo-Pacific margin, to form the Mongolian Orocline. Subduction and arc-building activity on the Palaeo-Pacific Ocean margin continued to the mid Mesozoic as the Indosinian and Yanshanian orogens.

  8. Effectiveness of the antimicrobial removal device, BACTEC 16B medium, and thiol broth in neutralizing antibacterial activities of imipenem, norfloxacin, and related agents.

    Science.gov (United States)

    Weinberg, E; Shungu, D L; Gadebusch, H H

    1984-02-01

    The Antimicrobial Removal Device (ARD), BACTEC 16B medium, and Thiol broth were evaluated for their effectiveness in reducing the activity of imipenem (IPM), cefoxitin, moxalactam, and ceftazidime in blood samples. In addition, the capability of the ARD and Thiol broth to bind norfloxacin and the ARD to bind oxolinic and nalidixic acids in urine samples was investigated. At the highest concentrations of the drugs tested (32 micrograms/ml for the four beta-lactams and 256 micrograms/ml for the three quinolinecarboxylic acids), there was at least a 95% reduction in the in vitro activity of each of the antibacterial agents for treated versus untreated samples. Of the compounds tested in the ARD system, the organic acids were more completely removed than were the beta-lactams. The Thiol broth was more effective than the ARD and the BACTEC 16B medium in inactivating imipenem, but it had no effect on the antibacterial activity of norfloxacin.

  9. Isolation, purification and characterization of a novel glucose oxidase from Penicillium sp. CBS 120262 optimally active at neutral pH

    CSIR Research Space (South Africa)

    Simpson, C

    2007-02-01

    Full Text Available A novel glucose oxidase (GOX), a Xavoenzyme, from Penicillium sp. was isolated, purified and partially characterised. Maximum activities of 1.08Umg‾1dry weight intracellular and 6.9Uml‾1 extracellular GOX were obtained. Isoelectric focussing...

  10. Effectiveness of the antimicrobial removal device, BACTEC 16B medium, and thiol broth in neutralizing antibacterial activities of imipenem, norfloxacin, and related agents.

    OpenAIRE

    Weinberg, E.; Shungu, D L; Gadebusch, H. H.

    1984-01-01

    The Antimicrobial Removal Device (ARD), BACTEC 16B medium, and Thiol broth were evaluated for their effectiveness in reducing the activity of imipenem (IPM), cefoxitin, moxalactam, and ceftazidime in blood samples. In addition, the capability of the ARD and Thiol broth to bind norfloxacin and the ARD to bind oxolinic and nalidixic acids in urine samples was investigated. At the highest concentrations of the drugs tested (32 micrograms/ml for the four beta-lactams and 256 micrograms/ml for the...

  11. Robust model-following control of a three-level Neutral Point Clamped shunt active filter in the medium voltage range

    Energy Technology Data Exchange (ETDEWEB)

    Munduate, Alejandro [BANTEC GROUP, Portuetxe 14, 2, 3. 20018 Donostia (Spain); Figueres, Emilio; Garcera, Gabriel [Universidad Politecnica de Valencia, Departamento de Ingenieria Electronica, Edificio 7F, Camino de Vera S/N, 46022 Valencia (Spain)

    2009-11-15

    This paper presents a robust control technique applied to a three-phase shunt active filter based on an NPC inverter, showing the modelling procedure needed to carry out the proposed control. The transfer functions for the control of the currents injected by the active filter are derived. The modelling is based on the abc/dq Park transformation of the AC system variables. The currents injected by the active filter are controlled in the synchronous orthogonal dq reference frame. The proposed robust current control technique is compared to a conventional PI controller in the dq frame, and to a PIS controller in the dq frame, consisting of a PI and resonant controllers synchronized to the frequencies of the nonlinear load current harmonics. On one hand, it is shown that the proposed technique improves the current harmonics compensation obtained by conventional PI control. On the other hand, it is found that the PIS controller is the best suited for current harmonics compensation among the controllers under study. Nevertheless, the RMF controller results in a simpler implementation than the PIS controller. Moreover, the proposed robust control has been applied to the DC-link voltage regulation, and it has been compared to a PI controller. It is shown that the robust control technique improves the dynamic response of the inverter to load steps without the need of a high crossover frequency of the DC-link voltage loop. (author)

  12. Neutrality Versus Materiality: A Thermodynamic Theory of Neutral Surfaces

    Directory of Open Access Journals (Sweden)

    Rémi Tailleux

    2016-09-01

    Full Text Available In this paper, a theory for constructing quasi-neutral density variables γ directly in thermodynamic space is formulated, which is based on minimising the absolute value of a purely thermodynamic quantity J n . Physically, J n has a dual dynamic/thermodynamic interpretation as the quantity controlling the energy cost of adiabatic and isohaline parcel exchanges on material surfaces, as well as the dependence of in-situ density on spiciness, in a description of water masses based on γ, spiciness and pressure. Mathematically, minimising | J n | in thermodynamic space is showed to be equivalent to maximising neutrality in physical space. The physics of epineutral dispersion is also reviewed and discussed. It is argued, in particular, that epineutral dispersion is best understood as the aggregate effect of many individual non-neutral stirring events (being understood here as adiabatic and isohaline events with non-zero buoyancy, so that it is only the net displacement aggregated over many events that is approximately neutral. This new view resolves an apparent paradox between the focus in neutral density theory on zero-buoyancy motions and the overwhelming evidence that lateral dispersion in the ocean is primarily caused by non-zero buoyancy processes such as tides, residual currents and sheared internal waves. The efficiency by which a physical process contributes to lateral dispersion can be characterised by its energy signature, with those processes releasing available potential energy (negative energy cost being more efficient than purely neutral processes with zero energy cost. The latter mechanism occurs in the wedge of instability, and its source of energy is the coupling between baroclinicity, thermobaricity, and density compensated temperature/salinity anomalies. Such a mechanism, which can only exist in a salty ocean, is speculated to be important for dissipating spiciness anomalies and neutral helicity. The paper also discusses potential

  13. Net Neutrality: Background and Issues

    National Research Council Canada - National Science Library

    Gilroy, Angele A

    2006-01-01

    .... The move to place restrictions on the owners of the networks that compose and provide access to the Internet, to ensure equal access and nondiscriminatory treatment, is referred to as "net neutrality...

  14. Incomplete Neutralization and Deviation from Sigmoidal Neutralization Curves for HIV Broadly Neutralizing Monoclonal Antibodies.

    Directory of Open Access Journals (Sweden)

    Laura E McCoy

    2015-08-01

    Full Text Available The broadly neutralizing HIV monoclonal antibodies (bnMAbs PG9, PG16, PGT151, and PGT152 have been shown earlier to occasionally display an unusual virus neutralization profile with a non-sigmoidal slope and a plateau at <100% neutralization. In the current study, we were interested in determining the extent of non-sigmoidal slopes and plateaus at <100% for HIV bnMAbs more generally. Using both a 278 panel of pseudoviruses in a CD4 T-cell (U87.CCR5.CXCR4 assay and a panel of 117 viruses in the TZM-bl assay, we found that bnMAbs targeting many neutralizing epitopes of the spike had neutralization profiles for at least one virus that plateaued at <90%. Across both panels the bnMAbs targeting the V2 apex of Env and gp41 were most likely to show neutralization curves that plateaued <100%. Conversely, bnMAbs targeting the high-mannose patch epitopes were less likely to show such behavior. Two CD4 binding site (CD4bs Abs also showed this behavior relatively infrequently. The phenomenon of incomplete neutralization was also observed in a large peripheral blood mononuclear cells (PBMC-grown molecular virus clone panel derived from patient viral swarms. In addition, five bnMAbs were compared against an 18-virus panel of molecular clones produced in 293T cells and PBMCs and assayed in TZM-bl cells. Examples of plateaus <90% were seen with both types of virus production with no consistent patterns observed. In conclusion, incomplete neutralization and non-sigmoidal neutralization curves are possible for all HIV bnMAbs against a wide range of viruses produced and assayed in both cell lines and primary cells with implications for the use of antibodies in therapy and as tools for vaccine design.

  15. Weak neutral-current interactions

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, R.M.

    1978-08-01

    The roles of each type of experiment in establishing uniquely the values of the the neutral-current couplings of u and d quarks are analyzed together with their implications for gauge models of the weak and electromagnetic interactions. An analysis of the neutral-current couplings of electrons and of the data based on the assumption that only one Z/sup 0/ boson exists is given. Also a model-independent analysis of parity violation experiments is discussed. 85 references. (JFP)

  16. 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...

  17. Rehabilitating drug-induced long-QT promoters: in-silico design of hERG-neutral cisapride analogues with retained pharmacological activity.

    Science.gov (United States)

    Durdagi, Serdar; Randall, Trevor; Duff, Henry J; Chamberlin, Adam; Noskov, Sergei Y

    2014-03-08

    The human ether-a-go-go related gene 1 (hERG1), which codes for a potassium ion channel, is a key element in the cardiac delayed rectified potassium current, IKr, and plays an important role in the normal repolarization of the heart's action potential. Many approved drugs have been withdrawn from the market due to their prolongation of the QT interval. Most of these drugs have high potencies for their principal targets and are often irreplaceable, thus "rehabilitation" studies for decreasing their high hERG1 blocking affinities, while keeping them active at the binding sites of their targets, have been proposed to enable these drugs to re-enter the market. In this proof-of-principle study, we focus on cisapride, a gastroprokinetic agent withdrawn from the market due to its high hERG1 blocking affinity. Here we tested an a priori strategy to predict a compound's cardiotoxicity using de novo drug design with molecular docking and Molecular Dynamics (MD) simulations to generate a strategy for the rehabilitation of cisapride. We focused on two key receptors, a target interaction with the (adenosine) receptor and an off-target interaction with hERG1 channels. An analysis of the fragment interactions of cisapride at human A2A adenosine receptors and hERG1 central cavities helped us to identify the key chemical groups responsible for the drug activity and hERG1 blockade. A set of cisapride derivatives with reduced cardiotoxicity was then proposed using an in-silico two-tier approach. This set was compared against a large dataset of commercially available cisapride analogs and derivatives. An interaction decomposition of cisapride and cisapride derivatives allowed for the identification of key active scaffolds and functional groups that may be responsible for the unwanted blockade of hERG1.

  18. 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.

  19. Biochemical identification of a neutral sphingomyelinase 1 (NSM1)-like enzyme as the major NSM activity in the DT40 B-cell line: absence of a role in the apoptotic response to endoplasmic reticulum stress.

    Science.gov (United States)

    Fensome, Amanda C; Josephs, Michelle; Katan, Matilda; Rodrigues-Lima, Fernando

    2002-01-01

    DT40 cells have approx. 10-fold higher Mg2+-dependent neutral sphingomyelinase (NSM) activity in comparison with other B-cell lines and contain very low acidic sphingomyelinase activity. Purification of this activity from DT40 cell membranes suggested the presence of one major NSM isoform. Although complete purification of this isoform could not be achieved, partially purified fractions were examined further with regard to the known characteristics of previously partially purified NSMs and the two cloned enzymes exhibiting in vitro NSM activity (NSM1 and NSM2). For a direct comparative study, highly purified brain preparations, purified NSM1 protein and Bacillus cereus enzyme were used. Analysis of the enzymic properties of the partially purified DT40 NSM, such as cation dependence, substrate specificity, redox regulation and stimulation by phosphatidylserine, together with the localization of this enzyme to the endoplasmic reticulum (ER), suggested that this NSM from DT40 cells corresponds to NSM1. Further studies aimed to correlate presence of the high levels of this NSM1-like activity in DT40 cells with the ability of these cells to accumulate ceramide and undergo apoptosis. When DT40 cells were stimulated to apoptose by a variety of agents, including the ER stress, an increase in endogenous ceramide levels was observed. However, these responses were not enhanced compared with another B-cell line (Nalm-6), characterized by low sphingomyelinase activity. In addition, DT40 cells were not more susceptible to ceramide accumulation and apoptosis when exposed to the ER stress compared with other apoptotic agents. Inhibition of de novo synthesis of ceramide partially inhibited its accumulation, indicating that the ceramide production in DT40 cells could be complex and, under some conditions, could involve both sphingomyelin hydrolysis and ceramide synthesis. PMID:12071841

  20. Spain: NATO or Neutrality,

    Science.gov (United States)

    1980-04-01

    French Socialist Party, "El Pais,’ 7 November 1978, p. 6. 2J.G. M6rigot and G. Cazenaire, "’Espagne et ]a Communaute Economique Europ~enne," Deense...States of America, and recognizing that science and technology are essential factors in meeting the growing needs and in furthering the general economic...between Institutions and entities of the two countries. Their cooperation and activities in the fields of science and technology will be subject to the

  1. Sono-incorporation of CuO nanoparticles on the surface and into the mesoporous hexatitanate layers: Enhanced Fenton-like activity in degradation of orange-G at its neutral pH

    Science.gov (United States)

    Sehati, S.; Entezari, M. H.

    2017-03-01

    In this work, for the first time, CuO/Ti6O13 mesoporous nanocomposite was synthesized by direct intercalation of CuO nanoparticles into hexatitanate layers in the presence of ultrasound. In fact mesoporous potassium hexatitanate with high pore size (44.94 nm) was used as a support. CuO nanoparticles were grown into the titanate pores which caused formation of ultra small CuO with uniform size and high surface area. In fact, titanate is considered as a substrate for better dispersion and nucleation of the CuO nanoparticles which prevented the agglomeration and overgrowth of guest molecules. The prepared sample was characterized by XRD, FE-SEM, TEM, UV-vis spectra, N2 adsorption-desorption, Raman spectra and FT-IR techniques. The product was used as a heterogeneous Fenton-like catalyst for the degradation of Orang G (OG). The effect of important parameters, including pH, H2O2 addition rate and catalyst loading on the decolorization of OG were investigated. Based on the results, CuO/Ti6O13 catalyst exhibited high catalytic activity for OG degradation in aqueous solution at neutral pH of the dye. Moreover, breaking of H2O2 during the catalytic reaction was monitored by spectroscopic method. The results confirmed the decomposition of H2O2 to produce rad OH which is the main active species for the degradation of OG.

  2. Neutral gas depletion in low temperature plasma

    Science.gov (United States)

    Fruchtman, A.

    2017-11-01

    Neutral depletion can significantly affect the steady state of low temperature plasmas. Processes that lead to neutral depletion and the resulting plasma–neutrals steady state are reviewed. Two such processes are due to collisions of neutrals with plasma. One process is the drag by ions that collide with neutrals and push them towards the wall. Another process is neutral-gas heating by collisions with plasma that makes the gas hotter at the discharge center. These processes, which usually occur under (static) pressure balance between plasma and neutrals, are called here ‘neutral pumping’. When collisions are negligible, neutrals that move ballistically between the chamber walls are depleted through ionization, a process called here ‘ion pumping’. The effect of the magnetic field on neutral depletion is explored in plasma in which the dynamics is governed by cross-field diffusion. Finally, neutral depletion in a flowing plasma is analyzed.

  3. Neutralization of bacterial endotoxins by frog antimicrobial peptides.

    Science.gov (United States)

    Schadich, Ermin; Mason, Drusilla; Cole, Anthony L

    2013-02-01

    The ability of skin antimicrobial peptides of the southern bell frog, Litoria raniformis, to neutralize in vitro the endotoxin, proinflammatory lipopolysaccharide (LPS) complex, from two different gram-negative bacterial pathogens, human pathogen Escherichia coli (0111:B4) and frog pathogen Klebsiella pneumoniae, was investigated. The LPS neutralization activity of the natural mixture of skin antimicrobial peptides was measured using chromogenic Limulus amebocyte lysate assays. These skin antimicrobial peptides neutralized the LPSs from both pathogens at physiologically relevant concentrations (IC(50)  endotoxin agents. © 2012 The Societies and Wiley Publishing Asia Pty Ltd.

  4. Plavica epithermal Au-Ag-Cu deposit in eastern Macedonia: Geology and 3D model of valuable component distribution in ore

    Science.gov (United States)

    Serafimovski, T.; Volkov, A. V.; Serafimovski, D.; Tasev, G.; Ivanovski, I.; Murashov, K. Yu.

    2017-07-01

    The Plavica Au-Ag-Cu deposit is related to the large Neogene volcanic center, which complicates the paleocaldera in the central Kratovo-Zletovo ore district of eastern Macedonia. Based on the geology, ore mineralogy, wall-rock alteration, and fluid inclusions, the Plavica deposit has been referred to the epithermal high-sulfidation type. The general 3D model of orebody at this deposit is based on its general geological structure and complex distribution of metal contents. The framework of the 3D model, which has been constructed in the ArcGIS System, comprises 195 exploration boreholes 47295.8 m in total length. The 3D model allows to a better understanding of distribution of mineralization and supplements the geological data on the deposit.

  5. Optical Neutrality: Invisibility without Cloaking

    OpenAIRE

    Hodges, Reed; Dean, Cleon; Durach, Maxim

    2016-01-01

    We show that it is possible to design an invisible wavelength-sized metal-dielectric metamaterial object without evoking cloaking. Our approach is an extension of the neutral inclusion concept by Zhou and Hu [Phys.Rev.E 74, 026607 (2006)] to Mie scatterers. We demonstrate that an increase of metal fraction in the metamaterial leads to a transition from dielectric-like to metal-like scattering, which proceeds through invisibility or optical neutrality of the scatterer. Formally this is due to ...

  6. A Novel Neutral Point Voltage Control Strategy for Three-Level NPC APF Based on SVPWM

    Directory of Open Access Journals (Sweden)

    Yao Xiaolong

    2015-01-01

    Full Text Available The unbalance of the neutral point voltage is an inherent problem of three-level neutral-point-clamped (NPC Active Power Filter (APF; this paper analyzes the causes of unbalanced neutral point voltage and studies the reason of the unbalance of the neutral point voltage. A novel neutral point voltage control strategy using Space Vector Pulse Width Modulation (SVPWM is proposed. The proposed strategy is based on the traditional SVPWM, by controlling the effect time of small vector, which can change the state of the midpoint voltage fluctuation, and the neutral point voltage can be maintained balance. The influence of the vector on neutral point balance is investigated in depth. Simulation results show the neutral point voltage balancing control strategy based on SPWM is effective.

  7. Higher Throughput Quantification of Neutralizing Antibody to Herpes Simplex Viruses.

    Directory of Open Access Journals (Sweden)

    Tamara P Blevins

    Full Text Available We report a rapid, higher throughput method for measuring neutralizing antibody to herpes simplex virus (HSV in human sera. Clinical isolates and sera from the Herpevac Trial for Women were used in a colorimetric assay in which infection of tissue culture (lack of neutralization was indicated by substrate metabolism by beta-galactosidase induced in the ELVIS cell line. The neutralization assay was optimized by addition of guinea pig complement, which particularly enhanced neutralizing antibody titers to HSV-2. Higher neutralizing antibody titers were also achieved using virus particles isolated from the supernatant of infected cells rather than lysate of infected cells as the source of virus. The effect of assay incubation time and incubation time with substrate were also optimized. We found that incubating with substrate until a standard optical density of 1.0 was reached permitted a better comparison among virus isolates, and achieved reliable measurement of neutralizing antibody activity. Interestingly, in contrast to results in the absence of complement, addition of complement allowed sera from HSV-2 gD-vaccinated subjects to neutralize HSV-1 and HSV-2 clinical and laboratory isolates with equal potency.

  8. Expression of apical Na(+)-L-glutamine co-transport activity, B(0)-system neutral amino acid co-transporter (B(0)AT1) and angiotensin-converting enzyme 2 along the jejunal crypt-villus axis in young pigs fed a liquid formula

    Science.gov (United States)

    Gut apical amino acid (AA) transport activity is high at birth and during suckling, thus being essential to maintain luminal nutrient-dependent mucosal growth through providing AA as essential metabolic fuel, substrates and nutrient stimuli for cellular growth. Because system-B(0) Na(+)-neutral AA c...

  9. Characterization of hierarchical α-MoO3 plates toward resistive heating synthesis: electrochemical activity of α-MoO3/Pt modified electrode toward methanol oxidation at neutral pH

    Science.gov (United States)

    Filippo, Emanuela; Baldassarre, Francesca; Tepore, Marco; Guascito, Maria Rachele; Chirizzi, Daniela; Tepore, Antonio

    2017-05-01

    The growth of MoO3 hierarchical plates was obtained by direct resistive heating of molybdenum foils at ambient pressure in the absence of any catalysts and templates. Plates synthesized after 60 min resistive heating typically grow in an single-crystalline orthorhombic structure that develop preferentially in the [001] direction, and are characterized by high resolution transmission electron microscopy, selected area diffraction pattern and Raman-scattering measurements. They are about 100-200 nm in thickness and a few tens of micrometers in length. As heating time proceeds to 80 min, plates of α-MoO3 form a branched structure. A more attentive look shows that primary plates formed at until 60 min could serve as substrates for the subsequent growth of secondary belts. Moreover, a full electrochemical characterization of α-MoO3 plates on platinum electrodes was done by cyclic voltammetric experiments, at pH 7 in phosphate buffer, to probe the activity of the proposed composite material as anode to methanol electro-oxidation. Reported results indicate that Pt MoO3 modified electrodes are appropriate to develop new an amperometric non-enzymatic sensor for methanol as well as to make anodes suitable to be used in direct methanol fuel cells working at neutral pH.

  10. Structural basis of hepatitis C virus neutralization by broadly neutralizing antibody HCV1

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Leopold; Giang, Erick; Robbins, Justin B.; Stanfield, Robyn L.; Burton, Dennis R.; Wilson, Ian A.; Law, Mansun (Scripps)

    2012-10-29

    Hepatitis C virus (HCV) infects more than 2% of the global population and is a leading cause of liver cirrhosis, hepatocellular carcinoma, and end-stage liver diseases. Circulating HCV is genetically diverse, and therefore a broadly effective vaccine must target conserved T- and B-cell epitopes of the virus. Human mAb HCV1 has broad neutralizing activity against HCV isolates from at least four major genotypes and protects in the chimpanzee model from primary HCV challenge. The antibody targets a conserved antigenic site (residues 412-423) on the virus E2 envelope glycoprotein. Two crystal structures of HCV1 Fab in complex with an epitope peptide at 1.8-{angstrom} resolution reveal that the epitope is a {beta}-hairpin displaying a hydrophilic face and a hydrophobic face on opposing sides of the hairpin. The antibody predominantly interacts with E2 residues Leu{sup 413} and Trp{sup 420} on the hydrophobic face of the epitope, thus providing an explanation for how HCV isolates bearing mutations at Asn{sup 415} on the same binding face escape neutralization by this antibody. The results provide structural information for a neutralizing epitope on the HCV E2 glycoprotein and should help guide rational design of HCV immunogens to elicit similar broadly neutralizing antibodies through vaccination.

  11. Antibodies to the envelope glycoprotein of human T cell leukemia virus type 1 robustly activate cell-mediated cytotoxic responses and directly neutralize viral infectivity at multiple steps of the entry process

    National Research Council Canada - National Science Library

    Kuo, Chien-Wen S; Mirsaliotis, Antonis; Brighty, David W

    2011-01-01

    ... fusion of the viral and cellular membranes. The envelope glycoproteins are recognized by neutralizing Abs and CTL following a protective immune response, and therefore, represent attractive components for a HTLV-1 vaccine...

  12. Traps for neutral radioactive atoms

    CERN Document Server

    Sprouse, G D; Grossman, J S; Orozco, L A; Pearson, M R

    2002-01-01

    We describe several methods for efficiently injecting a small number of radioactive atoms into a laser trap. The characteristics of laser traps that make them desirable for physics experiments are discussed and several different experimental directions are described. We describe recent experiments with the alkali element Fr and point to future directions of the neutral atom trapping program.

  13. Quantum Mechanics with Neutral Kaons

    OpenAIRE

    Bramon, A.; Garbarino, G.; Hiesmayr, B. C.

    2007-01-01

    We briefly illustrate a few tests of quantum mechanics which can be performed with entangled neutral kaon pairs at a Phi-factory. This includes a quantitative formulation of Bohr's complementarity principle, the quantum eraser phenomenon and various forms of Bell inequalities.

  14. Net Neutrality in the Netherlands

    NARCIS (Netherlands)

    van Eijk, N.

    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

  15. Study of the active filter for the cancellation of currents of the neutral in three-phase systems; Estudio del filtro activo para la cancelacion de corrientes de neutro en sistemas trifasicos

    Energy Technology Data Exchange (ETDEWEB)

    Diaz Saldierna, Luis Humberto

    2004-05-15

    The proliferation of the so called nonlinear loads has increased in a considerable way in the last years. These loads generate non sine waveforms in the current that consume, producing effects such as low power factor, generation of reactive power and harmonics, to mention some of them. Another problem shows up when an unbalance of loads exists in the three-phase systems with connection to the neutral (star connection); the unbalance generates circulation of currents through the neutral conductor, which can get to be of equal to greater magnitude than the phase currents; these are problems that degrade the quality of the supply and the consumption of electrical energy. Solutions such as the passive filters and active filters are used to face this kind of problems. The passive filters are used to attenuate the harmonics of current of more significant magnitude in three-phase systems non-connected to the neutral (delta connection), nevertheless the passive filters have considerable limitations, because they cannot compensate unbalance, and it is necessary a filter for every harmonic and its performance is adequate for constant loads. The active filters can be used to correct the power factor, since they can get to filter most of the LF harmonics, compensate the loads unbalance and the reactive power flow. In this work a study is made on the neutral currents associated to the active power and harmonic currents in the three-phase systems of four wires, the most active filters are chosen as a solution. The objective of the thesis is to analyze and to construct an active filter of current for the attenuation of current harmonics and the compensation of the load unbalance existing in a three-phase of four wires. The thesis document comprises five chapters and three appendixes, as it is next described: In chapter I a short introduction is presented on the problems and possible solutions of the same ones. In chapter II an analysis is made on the harmonic distortion and the

  16. Humanized-Single Domain Antibodies (VH/VHH that Bound Specifically to Naja kaouthia Phospholipase A2 and Neutralized the Enzymatic Activity

    Directory of Open Access Journals (Sweden)

    Wanpen Chaicumpa

    2012-07-01

    Full Text Available Naja kaouthia (monocled cobra venom contains many isoforms of secreted phospholipase A2 (sPLA2. The PLA2 exerts several pharmacologic and toxic effects in the snake bitten subject, dependent or independent on the enzymatic activity. N. kaouthia venom appeared in two protein profiles, P3 and P5, after fractionating the venom by ion exchange column chromatography. In this study, phage clones displaying humanized-camel single domain antibodies (VH/VHH that bound specifically to the P3 and P5 were selected from a humanized-camel VH/VHH phage display library. Two phagemid transfected E. coli clones (P3-1 and P3-3 produced humanized-VHH, while another clone (P3-7 produced humanized-VH. At the optimal venom:antibody ratio, the VH/VHH purified from the E. coli homogenates neutralized PLA2 enzyme activity comparable to the horse immune serum against the N. kaouthia holo-venom. Homology modeling and molecular docking revealed that the VH/VHH covered the areas around the PLA2 catalytic groove and inserted their Complementarity Determining Regions (CDRs into the enzymatic cleft. It is envisaged that the VH/VHH would ameliorate/abrogate the principal toxicity of the venom PLA2 (membrane phospholipid catabolism leading to cellular and subcellular membrane damage which consequently causes hemolysis, hemorrhage, and dermo-/myo-necrosis, if they were used for passive immunotherapy of the cobra bitten victim. The speculation needs further investigations.

  17. Optical neutrality: invisibility without cloaking.

    Science.gov (United States)

    Hodges, Reed; Dean, Cleon; Durach, Maxim

    2017-02-15

    We show that it is possible to design an invisible wavelength-sized metal-dielectric metamaterial object without evoking cloaking. Our approach is an extension of the neutral inclusion concept by Zhou and Hu [Phys. Rev. E74, 026607 (2006)PLEEE81063-651X10.1103/PhysRevE.74.026607] to Mie scatterers. We demonstrate that an increase of metal fraction in the metamaterial leads to a transition from dielectric-like to metal-like scattering, which proceeds through invisibility or optical neutrality of the scatterer. Formally this is due to cancellation of multiple scattering orders, similarly to plasmonic cloaking introduced by Alù and Engheta [Phys. Rev. E72, 016623 (2005)PLEEE81063-651X10.1103/PhysRevE.72.016623], but without introduction of the separation of the scatterer into cloak and hidden regions.

  18. Neutral atom traps of radioactives

    CERN Document Server

    Behr, J A

    2003-01-01

    Neutral atoms trapped with modern laser cooling techniques offer the promise of improving several broad classes of experiments with radioactive isotopes. In nuclear beta decay, neutrino spectroscopy from beta-recoil coincidences, along with highly polarized samples, enable experiments to search for non-Standard Model interactions, test whether parity symmetry is maximally violated, and search for new sources of time reversal violation. Ongoing efforts at TRIUMF, Los Alamos and Berkeley will be highlighted. The traps also offer bright sources for Doppler-free spectroscopy, particularly in high-Z atoms where precision measurements could measure the strength of weak neutral nucleon-nucleon and electron-nucleon interactions. Physics with francium atoms has been vigorously pursued at Stony Brook. Several facilities plan work with radioactive atom traps; concrete plans and efforts at KVI Groningen and Legnaro will be among those summarized. Contributions to the multidisciplinary field of trace analysis will be left...

  19. 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.

  20. Neutrality and the social contract

    Directory of Open Access Journals (Sweden)

    Ian J. Carroll

    2009-06-01

    Full Text Available Given the fact of moral disagreement, theories of state neutrality which rely on moral premises will have limited application, in that they will fail to motivate anyone who rejects the moral premises on which they are based. By contrast, contractarian theories can be consistent with moral scepticism, and can therefore avoid this limitation. In this paper, I construct a contractarian model which I claim is sceptically consistent and includes a principle of state neutrality as a necessary condition. The principle of neutrality which I derive incorporates two conceptions of neutrality (consequential neutrality and justificatory neutrality which have usually been thought of as distinct and incompatible. I argue that contractarianism gives us a unified account of these conceptions. Ultimately, the conclusion that neutrality can be derived without violating the constraint established by moral scepticism turns out to rely on an assumption of equal precontractual bargaining power. I do not attempt to defend this assumption here. If the assumption cannot be defended in a sceptically consistent fashion, then the argument for neutrality given here is claimed to be morally minimal, rather than fully consistent with moral scepticism. L’existence d’un désaccord sur les questions morales fait en sorte que les constructions théoriques de la neutralité de l’État se fondant sur des prémisses morales ne peuvent avoir qu’une application limitée, car elles échouent à motiver quiconque rejette ces prémisses fondatrices. Par opposition, les théories contractualistes peuvent s’accommoder d’un scepticisme moral et peuvent donc éviter cette limitation. Cet article développe un modèle contractualiste compatible avec le scepticisme et qui inclut comme condition nécessaire la neutralité de l’État. Le principe de neutralité que je dérive à partir de ce modèle incorpore deux conceptions de la neutralité, soit la neutralité des cons

  1. Response of neutral mesospheric density to geomagnetic forcing

    Science.gov (United States)

    Yi, Wen; Reid, Iain M.; Xue, Xianghui; Younger, Joel P.; Murphy, Damian J.; Chen, Tingdi; Dou, Xiankang

    2017-08-01

    We report an analysis of the neutral mesosphere density response to geomagnetic activity from January 2016 to February 2017 over Antarctica. Neutral mesospheric densities from 85 to 95 km are derived using data from the Davis meteor radar (68.5°S, 77.9°E) and the Microwave Limb Sounder on the Aura satellite. Spectral and Morlet wavelet analyses indicate that a prominent oscillation with a periodicity of 13.5 days is observed in the mesospheric density during the declining phase of solar cycle 24 and is associated with variations in solar wind high-speed streams and recurrent geomagnetic activity. The periodic oscillation in density shows a strong anticorrelation with periodic changes in the auroral electrojet index. These results indicate that a significant decrease in neutral mesospheric density as the geomagnetic activity enhances.

  2. 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.

  3. A new indicator mineral methodology based on a generic Bi-Pb-Te-S mineral inclusion signature in detrital gold from porphyry and low/intermediate sulfidation epithermal environments in Yukon Territory, Canada

    Science.gov (United States)

    Chapman, R. J.; Allan, M. M.; Mortensen, J. K.; Wrighton, T. M.; Grimshaw, M. R.

    2017-12-01

    Porphyry-epithermal and orogenic gold are two of the most important styles of gold-bearing mineralization within orogenic belts. Populations of detrital gold resulting from bulk erosion of such regions may exhibit a compositional continuum wherein Ag, Cu, and Hg in the gold alloy may vary across the full range exhibited by natural gold. This paper describes a new methodology whereby orogenic and porphyry-epithermal gold may be distinguished according to the mineralogy of microscopic inclusions observed within detrital gold particles. A total of 1459 gold grains from hypogene, eluvial, and placer environments around calc-alkaline porphyry deposits in Yukon (Nucleus-Revenue, Casino, Sonora Gulch, and Cyprus-Klaza) have been characterized in terms of their alloy compositions (Au, Ag, Cu, and Hg) and their inclusion mineralogy. Despite differences in the evolution of the different magmatic hydrothermal systems, the gold exhibits a clear Bi-Pb-Te-S mineralogy in the inclusion suite, a signature which is either extremely weak or (most commonly) absent in both Yukon orogenic gold and gold from orogenic settings worldwide. Generic systematic compositional changes in ore mineralogy previously identified across the porphyry-epithermal transition have been identified in the corresponding inclusion suites observed in samples from Yukon. However, the Bi-Te association repeatedly observed in gold from the porphyry mineralization persists into the epithermal environment. Ranges of P-T-X conditions are replicated in the geological environments which define generic styles of mineralization. These parameters influence both gold alloy composition and ore mineralogy, of which inclusion suites are a manifestation. Consequently, we propose that this methodology approach can underpin a widely applicable indicator methodology based on detrital gold.

  4. Boron neutron capture therapy of glioblastoma multiforme using the p- boronophenylalanine-fructose complex and epithermal neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Coderre, J.A.; Chanana, A.D.; Joel, D.D.; Liu, H.B.; Slatkin, D.N.; Wielopolski, L. [Brookhaven National Lab., Upton, NY (United States); Bergland, R.; Elowitz, E. [Beth Israel Medical Center, New York, NY (United States). Dept. of Neurosurgery; Chadha, M. [Beth Israel Medical Center, New York, NY (United States). Dept. of Radiation Oncology

    1994-12-31

    The amino acid analogue p-boronophenylalanine (BPA) is under investigation as a neutron capture agent for BNCT of glioblastoma multiforme. A series of patients undergoing surgical removal of tumor received BPA orally as the free amino acid. Favorable tumor/blood boron concentration ratios were obtained but the absolute amount of boron in the tumor would have been insufficient for BNCT. BPA can be solubilized at neutral pH by complexation with fructose (BPA-F). Studies with rats suggest that intraperitoneal injection of BPA-F complex produces a much higher tumor boron concentration to rat intracerebral 9L gliosarcoma that were possible with oral BPA. Higher boron concentrations have allowed higher tumor radiation doses to be delivered while maintaining the dose to the normal brain vascular endothelium below the threshold of tolerance. The experience to date of the administration of BPA-F to one patient is provided in this report.

  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

    of neutralizing antibodies to the primary virus isolates was detected 13-45 weeks after seroconversion. Emergence of escape virus with reduced sensitivity to neutralization by autologous sera was demonstrated. The patients subsequently developed neutralizing antibodies against the escape virus but after a delay...... escape virus may be part of the explanation of the apparent failure of the immune system to control HIV infection....

  6. Mineralogical Distribution of Germanium, Gallium and Indium at the Mt Carlton High-Sulfidation Epithermal Deposit, NE Australia, and Comparison with Similar Deposits Worldwide

    Directory of Open Access Journals (Sweden)

    Fredrik Sahlström

    2017-11-01

    Full Text Available Germanium, gallium and indium are in high demand due to their growing usage in high-tech and green-tech applications. However, the mineralogy and the mechanisms of concentration of these critical elements in different types of hydrothermal ore deposits remain poorly constrained. We investigated the mineralogical distribution of Ge, Ga and In at the Mt Carlton high-sulfidation epithermal deposit in NE Australia, using electron probe microanalysis and laser ablation inductively-coupled plasma mass spectrometry. Parageneses from which selected minerals were analyzed include: Stage 1 acid sulfate alteration (alunite, Stage 2A high-sulfidation enargite mineralization (enargite, argyrodite, sphalerite, pyrite, barite, Stage 2B intermediate-sulfidation sphalerite mineralization (sphalerite, pyrite, galena and Stage 3 hydrothermal void fill (dickite. Moderate to locally high concentrations of Ga were measured in Stage 1 alunite (up to 339 ppm and in Stage 3 dickite (up to 150 ppm. The Stage 2A ores show enrichment in Ge, which is primarily associated with argyrodite (up to 6.95 wt % Ge and Ge-bearing enargite (up to 2189 ppm Ge. Co-existing sphalerite has comparatively low Ge content (up to 143 ppm, while Ga (up to 1181 ppm and In (up to 571 ppm are higher. Sphalerite in Stage 2B contains up to 611 ppm Ge, 2829 ppm Ga and 2169 ppm In, and locally exhibits fine colloform bands of an uncharacterized Zn-In mineral with compositions close to CuZn2(In,GaS4. Barite, pyrite and galena which occur in association with Stage 2 mineralization were found to play negligible roles as carriers of Ge, Ga and In at Mt Carlton. Analyzed reference samples of enargite from seven similar deposits worldwide have average Ge concentrations ranging from 12 to 717 ppm (maximum 2679 ppm. The deposits from which samples showed high enrichment in critical elements in this study are all hosted in stratigraphic sequences that locally contain carbonaceous sedimentary rocks. In

  7. 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.

  8. Neutral beamline with improved ion energy recovery

    Science.gov (United States)

    Kim, Jinchoon

    1984-01-01

    A neutral beamline employing direct energy recovery of unneutralized residual ions is provided which enhances the energy recovery of the full energy ion component of the beam exiting the neutralizer cell, and thus improves the overall neutral beamline efficiency. The unneutralized full energy ions exiting the neutralizer are deflected from the beam path and the electrons in the cell are blocked by a magnetic field applied transverse to the beam direction in the neutral izer exit region. The ions which are generated at essentially ground potential and accelerated through the neutralizer cell by a negative acceleration voltage are collected at ground potential. A neutralizer cell exit end region is provided which allows the magnetic and electric fields acting on the exiting ions to be loosely coupled. As a result, the fractional energy ions exiting the cell are reflected onto and collected at an interior wall of the neutralizer formed by the modified end geometry, and thus do not detract from the energy recovery efficiency of full energy ions exiting the cell. Electrons within the neutralizer are prevented from exiting the neutralizer end opening by the action of crossed fields drift (ExB) and are terminated to a collector collar around the downstream opening of the neutralizer. The correct combination of the extended neutralizer end structure and the magnet region is designed so as to maximize the exit of full energy ions and to contain the fractional energy ions.

  9. The Net Neutrality Debate: The Basics

    Science.gov (United States)

    Greenfield, Rich

    2006-01-01

    Rich Greenfield examines the basics of today's net neutrality debate that is likely to be an ongoing issue for society. Greenfield states the problems inherent in the definition of "net neutrality" used by Common Cause: "Network neutrality is the principle that Internet users should be able to access any web content they choose and…

  10. Neutralizing antibodies against two HIV-1 strains in consecutively collected serum samples: cross neutralization and association to HIV-1 related disease

    DEFF Research Database (Denmark)

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

    1992-01-01

    97 sera collected during a 10-year period from 10 HIV-1 infected individuals were tested for neutralizing capacity against a virus isolate FICPH-22 obtained from a Danish AIDS patient, and the laboratory strain HTLV-IIIB. Three patterns of serum neutralizing activity were demonstrated: (a) patients...

  11. ORNL positive ion neutral beam program

    Energy Technology Data Exchange (ETDEWEB)

    Whealton, J.H.; Haselton, H.H.; Barber, G.C.

    1978-01-01

    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.

  12. Thermodynamics of neutral protein evolution.

    Science.gov (United States)

    Bloom, Jesse D; Raval, Alpan; Wilke, Claus O

    2007-01-01

    Naturally evolving proteins gradually accumulate mutations while continuing to fold to stable structures. This process of neutral evolution is an important mode of genetic change and forms the basis for the molecular clock. We present a mathematical theory that predicts the number of accumulated mutations, the index of dispersion, and the distribution of stabilities in an evolving protein population from knowledge of the stability effects (delta deltaG values) for single mutations. Our theory quantitatively describes how neutral evolution leads to marginally stable proteins and provides formulas for calculating how fluctuations in stability can overdisperse the molecular clock. It also shows that the structural influences on the rate of sequence evolution observed in earlier simulations can be calculated using just the single-mutation delta deltaG values. We consider both the case when the product of the population size and mutation rate is small and the case when this product is large, and show that in the latter case the proteins evolve excess mutational robustness that is manifested by extra stability and an increase in the rate of sequence evolution. All our theoretical predictions are confirmed by simulations with lattice proteins. Our work provides a mathematical foundation for understanding how protein biophysics shapes the process of evolution.

  13. Discrete symmetries with neutral mesons

    Science.gov (United States)

    Bernabéu, José

    2018-01-01

    Symmetries, and Symmetry Breakings, in the Laws of Physics play a crucial role in Fundamental Science. Parity and Charge Conjugation Violations prompted the consideration of Chiral Fields in the construction of the Standard Model, whereas CP-Violation needed at least three families of Quarks leading to Flavour Physics. In this Lecture I discuss the Conceptual Basis and the present experimental results for a Direct Evidence of Separate Reversal-in-Time T, CP and CPT Genuine Asymmetries in Decaying Particles like Neutral Meson Transitions, using Quantum Entanglement and the Decay as a Filtering Measurement. The eight transitions associated to the Flavour-CP eigenstate decay products of entangled neutral mesons have demonstrated with impressive significance a separate evidence of TRV and CPV in Bd-physics, whereas a CPTV asymmetry shows a 2σ effect interpreted as an upper limit. Novel CPTV observables are discussed for K physics at KLOE-2, including the difference between the semileptonic asymmetries from KL and KS, the ratios of double decay rate Intensities to Flavour-CP eigenstate decay products and the ω-effect. Their observation would lead to a change of paradigm beyond Quantum Field Theory, however there is nothing in Quantum Mechanics forbidding CPTV.

  14. Proteolytische activiteit bij neutrale pH in rundermilt

    NARCIS (Netherlands)

    Marrink, Jan

    1969-01-01

    Intracellular enzymes, hydrolysing proteins optimally at acid pH values (acid proteases), have been studied in detail by several investigators. The existence of proteolytic activity at neutral pH in animal tissue extracts, on the other hand, has often been mentioned, but with few reports on the

  15. A neutral model of low-severity fire regimes

    Science.gov (United States)

    Don McKenzie; Amy E. Hessl

    2008-01-01

    Climate, topography, fuel loadings, and human activities all affect spatial and temporal patterns of fire occurrence. Because fire occurrence is a stochastic process, an understanding of baseline variability is necessary in order to identify constraints on surface fire regimes. With a suitable null, or neutral, model, characteristics of natural fire regimes estimated...

  16. Neutralization of Soybean Oil Deodorizer Distillate for Vitamin Supplement Production

    Directory of Open Access Journals (Sweden)

    Cibelem Iribarrem Benites

    2014-01-01

    Full Text Available Soybean oil deodorizer distillate (SODD, a byproduct of the soybean oil refining process, is a complex mixture of compounds, such as free fatty acids (FFA, hydrocarbons, and sterols, such as tocopherols, a class of major natural antioxidants with vitamin E activity. As the utilization of SODD for tocopherol extraction is shown to be not economically viable, SODD in the semirefined form (neutral is an interesting alternative to animal and possibly human diet enrichment. This study aimed to evaluate the SODD neutralization process varying the alkali (Na2CO3 concentration, temperature, and homogenization time. The optimal conditions for the neutralizing process, in order to obtain the greatest reduction in FFA content, the lowest leaching of tocopherols, and the greatest yield, were the following: Na2CO2 concentration of 4.34 N, temperature of 45.8°C, and homogenization time of 3 min 20 s. The FFA content was reduced from 53.4% to 6.1% after the initial neutralization, thus requiring a second neutralization step. The final FFA content was of 1.8% and total tocopherol (TT accounted for about 11% of SODD.

  17. Radiative lifetimes of neutral cerium

    Science.gov (United States)

    Den Hartog, E. A.; Buettner, K. P.; Lawler, J. E.

    2009-04-01

    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.

  18. $\\tau$ decays with neutral kaons

    CERN Document Server

    Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Anderson, K.J.; Arcelli, S.; Asai, S.; Ashby, S.F.; Axen, D.; Azuelos, G.; Bailey, I.; Ball, A.H.; Barberio, E.; Barlow, Roger J.; Batley, J.R.; Baumann, S.; Behnke, T.; Bell, Kenneth Watson; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bloodworth, I.J.; Bock, P.; Bohme, J.; Boeriu, O.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Capiluppi, P.; Carnegie, R.K.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Chrisman, D.; Ciocca, C.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Conboy, J.E.; Cooke, O.C.; Couchman, J.; Couyoumtzelis, C.; Coxe, R.L.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; Davis, R.; de Roeck, A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Estabrooks, P.G.; Etzion, E.; Fabbri, F.; Fanfani, A.; Fanti, M.; Faust, A.A.; Feld, L.; Ferrari, P.; Fiedler, F.; Fierro, M.; Fleck, I.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gingrich, D.M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Hajdu, C.; Hanson, G.G.; Hansroul, M.; Hapke, M.; Harder, K.; Harel, A.; Hargrove, C.K.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Herten, G.; Heuer, R.D.; Hildreth, M.D.; Hill, J.C.; Hobson, P.R.; Hocker, James Andrew; Hoffman, Kara Dion; Homer, R.J.; Honma, A.K.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Imrie, D.C.; Ishii, K.; Jacob, F.R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P.I.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klier, A.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Kolrep, M.; Komamiya, S.; Kowalewski, Robert V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lauber, J.; Lawson, I.; Layter, J.G.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; Lillich, J.; List, B.; Littlewood, C.; Lloyd, A.W.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Martinez, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; Mckigney, E.A.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Merritt, F.S.; Mes, H.; Meyer, I.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oakham, F.G.; Odorici, F.; Ogren, H.O.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Przybycien, M.; Quadt, A.; Rembser, C.; Rick, H.; Robins, S.A.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rossi, A.M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W.M.; Sarkisian, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schmitt, S.; Schoning, A.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Siroli, G.P.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Sproston, M.; Stahl, A.; Stephens, K.; Stoll, K.; Strom, David M.; Strohmer, R.; Surrow, B.; Talbot, S.D.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomas, J.; Thomson, M.A.; Torrence, E.; Towers, S.; Trefzger, T.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Van Kooten, Rick J.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wackerle, F.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; White, J.S.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.

    2000-01-01

    The branching ratio of the tau lepton to a neutral K meson is measured from a sample of approximately 200,000 tau decays recorded by the OPAL detector at centre-of-mass energies near the Z0 resonance. The measurement is based on two samples which identify one-prong tau decays with KL and KS mesons. The combined branching ratios are measured to be B(tau- -->pi- K0bar nutau) = (9.33+-0.68+-0.49)x10^-3 B(tau- -->pi- K0bar [>=1pi0] nutau) = (3.24+-0.74+-0.66)x10^-3 B(tau- -->K- K0bar [>=0pi0] nutau) = (3.30+-0.55+-0.39)x10^-3 where the first error is statistical and the second systematic.

  19. 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.

  20. 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.

  1. 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.

  2. Escape from neutralization by the respiratory syncytial virus-specific neutralizing monoclonal antibody palivizumab is driven by changes in on-rate of binding to the fusion protein

    Energy Technology Data Exchange (ETDEWEB)

    Bates, John T. [The Vanderbilt Vaccine Center, Departments of Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN (United States); Keefer, Christopher J. [The Vanderbilt Vaccine Center, Departments of Pediatrics, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN (United States); Slaughter, James C. [The Vanderbilt Vaccine Center, Departments of Biostatistics and Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN (United States); Kulp, Daniel W. [IAVI Neutralizing Antibody Center and Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA (United States); Schief, William R. [IAVI Neutralizing Antibody Center and Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA (United States); Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA (United States); Crowe, James E., E-mail: james.crowe@vanderbilt.edu [The Vanderbilt Vaccine Center, Departments of Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN (United States); The Vanderbilt Vaccine Center, Departments of Pediatrics, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN (United States)

    2014-04-15

    The role of binding kinetics in determining neutralizing potency for antiviral antibodies is poorly understood. While it is believed that increased steady-state affinity correlates positively with increased virus-neutralizing activity, the relationship between association or dissociation rate and neutralization potency is unclear. We investigated the effect of naturally-occurring antibody resistance mutations in the RSV F protein on the kinetics of binding to palivizumab. Escape from palivizumab-mediated neutralization of RSV occurred with reduced association rate (K{sub on}) for binding to RSV F protein, while alteration of dissociation rate (K{sub off}) did not significantly affect neutralizing activity. Interestingly, linkage of reduced K{sub on} with reduced potency mirrored the effect of increased K{sub on} found in a high-affinity enhanced potency palivizumab variant (motavizumab). These data suggest that association rate is the dominant factor driving neutralization potency for antibodies to RSV F protein antigenic site A and determines the potency of antibody somatic variants or efficiency of escape of viral glycoprotein variants. - Highlights: • The relationship of affinity to neutralization for virus antibodies is uncertain. • Palivizumab binds to RSV escape mutant fusion proteins, but with reduced affinity. • Association rate (K{sub on}) correlated well with the potency of neutralization.

  3. Clinical islet isolation outcomes with a highly purified neutral protease for pancreas dissociation.

    Science.gov (United States)

    O'Gorman, Doug; Kin, Tatsuya; Pawlick, Rena; Imes, Sharleen; Senior, Peter A; Shapiro, A M James

    2013-01-01

    Pancreas dissociation is a critical initial component of the islet isolation procedure and introduces high variability based on factors including the enzyme type, specificity and potency. Product refinement and alterations to the application strategies have improved isolation outcomes over time; however, islet utilization from donor organs remains low. In this study we evaluate a low endotoxin-high activity grade neutral protease in clinical islet isolation. The use of a non-collagenolytic enzyme, either thermolysin or high active neutral protease, was randomized in clinical islet isolations to evaluate efficacy. Additionally a retrospective comparison to neutral protease NB was conducted. The thermolysin group had lower trapped islet population and increased purity and post-culture islet mass in comparison to high active grade neutral protease. Comparison of neutral protease NB GMP grade to high active neutral protease displayed no measurable difference in islet mass or viability and transplantation outcomes at 1 mo post-transplant were favorable for both groups. High activity neutral protease can generate clinical grade islets and may prove beneficial to islet function and viability based on a reduced endotoxin load but dosing of neutral protease requires ongoing optimization.

  4. 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...... escape virus may be part of the explanation of the apparent failure of the immune system to control HIV infection....... of neutralizing antibodies to the primary virus isolates was detected 13-45 weeks after seroconversion. Emergence of escape virus with reduced sensitivity to neutralization by autologous sera was demonstrated. The patients subsequently developed neutralizing antibodies against the escape virus but after a delay...

  5. Pitfalls in efficacy testing – how important is the validation of neutralization of chlorhexidine digluconate?

    Directory of Open Access Journals (Sweden)

    Heisig Peter

    2008-12-01

    Full Text Available Abstract Background Effective neutralization of active agents is essential to obtain valid efficacy results, especially when non-volatile active agents like chlorhexidine digluconate (CHG are tested. The aim of this study was to determine an effective and non-toxic neutralizing mixture for a propan-1-ol solution containing 2% CHG. Methods Experiments were carried out according to ASTM E 1054-02. The neutralization capacity was tested separately with five challenge microorganisms in suspension, and with a rayon swab carrier. Either 0.5 mL of the antiseptic solution (suspension test or a saturated swab with the antiseptic solution (carrier test was added to tryptic soy broth containing neutralizing agents. After the samples were mixed, aliquots were spread immediately and after 3 h of storage at 2 – 8°C onto tryptic soy agar containing a neutralizing mixture. Results The neutralizer was, however, not consistently effective in the suspension test. Immediate spread yielded a valid neutralization with Staphylococcus aureus, Staphylococcus epidermidis and Corynebacterium jeikeium but not with Micrococcus luteus (p Candida albicans (p Staphylococcus epidermidis (p Corynebacterium jeikeium (p = 0.044. In the carrier test, the neutralizing mixture was found to be effective and non toxic to all challenge microorganisms when spread immediately. However, after 3 h storage of the neutralized active agents significant carry-over activity of CHG against Micrococcus luteus (p = 0.004; Tukey HSD was observed. Conclusion Without effective neutralization in the sampling fluid, non-volatile active ingredients will continue to reduce the number of surviving microorganisms after antiseptic treatment even if the sampling fluid is kept cold straight after testing. This can result in false-positive antiseptic efficacy data. Attention should be paid during the neutralization validation process to the amount of antiseptic solution, the storage time and to the choice of

  6. Governance Instruments for Energy Neutral Housing Developments

    OpenAIRE

    Qi Han; Sahul Reddy Kadarpeta; Bauke de Vries

    2011-01-01

    Netherlands has set national energy targets for year 2020 following the European Union vision. In this context at the local level Eindhoven Municipality has set its ambition to go energy neutral in housing sector by 2020 and decided to develop new energy neutral housing areas. Lack of strict regulations and appropriate forms of support aimed at relevant stakeholders involved has attributed to the lack of acceptance for energy neutral housing in the current housing market. Further lack of a de...

  7. Evidence for de-sulfidation to form native electrum in the Fire Creek epithermal gold-silver deposit, north-central Nevada

    Science.gov (United States)

    Perez, J.; Day, J. M.; Cook, G. W.

    2012-12-01

    The Fire Creek property is a newly developed and previously unstudied epithermal Au-Ag deposit located in the Northern Shoshone range of north central Nevada. The mineralization occurs within and above en echelon N-NW trending basaltic dykes that are hosted within a co-genetic and bimodal suite of mid-Miocene basalts and andesites formed in association with the Yellowstone hotspot-track. Previous studies of Au-Ag mineralization in the Great Basin have focused primarily on extensively mined and/or low-grade deposits. Therefore, the ability for unrestricted sampling of a major Au-Ag deposit early in its exploration and development represents an opportunity for refined understanding of epithermal ore genesis processes. New petrology reveals at least two distinct pulses of mineralization that in relative order of timing are: 1) S-rich veins which are associated with initial host-rock alteration; 2) quartz- and/or calcite-rich veins which vary from fine-grained to lath-like quartz crystals with large calcite crystals in vein centers. Native electrum occurs only within the second phase of mineralization and typically occurs within quartz and adjacent to cross-cut first-phase S-rich veins. In places the electrum appears to replace or form overgrowths around existing sulfide phases. High levels of gold and silver are found in both the first (0.8 g Au/tonne) and second-phase pulses (37 g Au/tonne). Fire Creek shares many similarities with its northern neighbor, the Mule Canyon Au-Ag deposit, with high Fe sulfide contents for some of the ores, altered wall-rocks and the presence of narrow and discontinuous gold-bearing siliceous veins. Like Fire Creek, Mule Canyon possesses two distinct mineralizing phases, a sulfide rich and a late stage calcite/silica assemblage. The first pulse appears to be identical in both locations with a variation of disseminated to euhedral iron-sulfides and associated intense alteration of host rock. However, Fire Creek differs from Mule Canyon in

  8. Mineralized breccia clasts: a window into hidden porphyry-type mineralization underlying the epithermal polymetallic deposit of Cerro de Pasco (Peru)

    Science.gov (United States)

    Rottier, Bertrand; Kouzmanov, Kalin; Casanova, Vincent; Bouvier, Anne-Sophie; Baumgartner, Lukas P.; Wälle, Markus; Fontboté, Lluís

    2018-01-01

    Cerro de Pasco (Peru) is known for its large epithermal polymetallic (Zn-Pb-Ag-Cu-Bi) mineralization emplaced at shallow level, a few hundred meters below the paleo-surface, at the border of a large diatreme-dome complex. Porphyry-style veins crosscutting hornfels and magmatic rock clasts are found in the diatreme breccia and in quartz-monzonite porphyry dikes. Such mineralized veins in clasts allow investigation of high-temperature porphyry-style mineralization developed in the deep portions of magmatic-hydrothermal systems. Quartz in porphyry-style veins contains silicate melt inclusions as well as fluid and solid mineral inclusions. Two types of high-temperature (> 600 °C) quartz-molybdenite-(chalcopyrite)-(pyrite) veins are found in the clasts. Early, thin (1-2 mm), and sinuous HT1 veins are crosscut by slightly thicker (up to 2 cm) and more regular HT2 veins. The HT1 vein quartz hosts CO2- and sulfur-rich high-density vapor inclusions. Two subtypes of the HT1 veins have been defined, based on the nature of mineral inclusions hosted in quartz: (i) HT1bt veins with inclusions of K-feldspar, biotite, rutile, and minor titanite and (ii) HT1px veins with inclusions of actinolite, augite, titanite, apatite, and minor rutile. Using an emplacement depth of the veins of between 2 and 3 km (500 to 800 bar), derived from the diatreme breccia architecture and the supposed erosion preceding the diatreme formation, multiple mineral thermobarometers are applied. The data indicate that HT1 veins were formed at temperatures > 700 °C. HT2 veins host assemblages of polyphase brine inclusions, generally coexisting with low-density vapor-rich inclusions, trapped at temperatures around 600 °C. Rhyolitic silicate melt inclusions found in both HT1 and HT2 veins represent melt droplets transported by the ascending hydrothermal fluids. LA-ICP-MS analyses reveal a chemical evolution coherent with the crystallization of an evolved rhyolitic melt. Quartz from both HT1 and HT2 veins

  9. Binding neutral information to emotional contexts: Brain dynamics of long-term recognition memory.

    Science.gov (United States)

    Ventura-Bort, Carlos; Löw, Andreas; Wendt, Julia; Moltó, Javier; Poy, Rosario; Dolcos, Florin; Hamm, Alfons O; Weymar, Mathias

    2016-04-01

    There is abundant evidence in memory research that emotional stimuli are better remembered than neutral stimuli. However, effects of an emotionally charged context on memory for associated neutral elements is also important, particularly in trauma and stress-related disorders, where strong memories are often activated by neutral cues due to their emotional associations. In the present study, we used event-related potentials (ERPs) to investigate long-term recognition memory (1-week delay) for neutral objects that had been paired with emotionally arousing or neutral scenes during encoding. Context effects were clearly evident in the ERPs: An early frontal ERP old/new difference (300-500 ms) was enhanced for objects encoded in unpleasant compared to pleasant and neutral contexts; and a late central-parietal old/new difference (400-700 ms) was observed for objects paired with both pleasant and unpleasant contexts but not for items paired with neutral backgrounds. Interestingly, objects encoded in emotional contexts (and novel objects) also prompted an enhanced frontal early (180-220 ms) positivity compared to objects paired with neutral scenes indicating early perceptual significance. The present data suggest that emotional--particularly unpleasant--backgrounds strengthen memory for items encountered within these contexts and engage automatic and explicit recognition processes. These results could help in understanding binding mechanisms involved in the activation of trauma-related memories by neutral cues.

  10. On implicit abstract neutral nonlinear differential equations

    Energy Technology Data Exchange (ETDEWEB)

    Hernández, Eduardo, E-mail: lalohm@ffclrp.usp.br [Universidade de São Paulo, Departamento de Computação e Matemática, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto (Brazil); O’Regan, Donal, E-mail: donal.oregan@nuigalway.ie [National University of Ireland, School of Mathematics, Statistics and Applied Mathematics (Ireland)

    2016-04-15

    In this paper we continue our developments in Hernández and O’Regan (J Funct Anal 261:3457–3481, 2011) on the existence of solutions for abstract neutral differential equations. In particular we extend the results in Hernández and O’Regan (J Funct Anal 261:3457–3481, 2011) for the case of implicit nonlinear neutral equations and we focus on applications to partial “nonlinear” neutral differential equations. Some applications involving partial neutral differential equations are presented.

  11. Emissions trading and profit-neutral grandfathering

    Energy Technology Data Exchange (ETDEWEB)

    Hepburn, Cameron; Ritz, Robert; Quah, John (Oxford Univ., Smith School of Enterprise and the Environment, Oxford (United Kingdom))

    2008-07-01

    This paper examines the amount of grandfathering needed for an emissions trading scheme (ETS) to have a neutral impact on firm profits. We provide a simple formula to calculate profit-neutral grandfathering in an asymmetric Cournot model with a general demand function. Using this formula, we obtain estimates of profit-neutral grandfathering for the electricity, cement, newsprint and steel industries. Under the current EU ETS, firms obtain close to full grandfathering. We find no evidence that any industry as a whole could be worse off with full grandfathering. We also show that the common presumption that a higher rate of cost pass-through lowers profit-neutral grandfathering is unreliable

  12. Specificity of the autologous neutralizing antibody response.

    Science.gov (United States)

    Moore, Penny L; Gray, Elin S; Morris, Lynn

    2009-09-01

    It has long been known that autologous neutralizing antibodies (AnAbs) exert pressure on the envelope of HIV, resulting in neutralization escape. However, recently, progress has been made in uncovering the precise targets of these potent early antibodies. AnAbs primarily target variable regions of the HIV-1 envelope, explaining the strain-specificity of these antibodies. Despite high neutralizing potential and cross-reactivity, anti-V3 antibodies do not contribute to autologous neutralization. The V1V2 is commonly immunogenic in early HIV-1 and simian human immunodeficiency virus infections, though the nature of these epitopes remains to be determined. In subtype C viruses, the C3 region is a neutralization target, possibly as a result of its more exposed and amphipathic structure. Autologous neutralization appears to be mediated by very few AnAb specificities that develop sequentially suggesting the possibility of immunological hierarchies for both binding and neutralizing antibodies. The role of AnAbs in preventing superinfection and in restricting virus replication is reexamined in the context of recent data. New studies have greatly contributed toward our understanding of the specificities mediating autologous neutralization and highlighted potential vulnerabilities on transmitted viruses. However, the contribution of AnAbs to the development of neutralization breadth remains to be characterized.

  13. Lack of MERS coronavirus neutralizing antibodies in humans, eastern province, Saudi Arabia.

    Science.gov (United States)

    Gierer, Stefanie; Hofmann-Winkler, Heike; Albuali, Waleed H; Bertram, Stephanie; Al-Rubaish, Abdullah M; Yousef, Abdullah A; Al-Nafaie, Awatif N; Al-Ali, Amein K; Obeid, Obeid E; Alkharsah, Khaled R; Pöhlmann, Stefan

    2013-12-01

    We used a lentiviral vector bearing the viral spike protein to detect neutralizing antibodies against Middle East respiratory syndrome coronavirus (MERS-CoV) in persons from the Eastern Province of Saudi Arabia. None of the 268 samples tested displayed neutralizing activity, which suggests that MERS-CoV infections in humans are infrequent in this province.

  14. Neutral current induced neutrino oscillations in a supernova

    CERN Document Server

    Kusenko, A; Kusenko, Alexander; Segre, Gino

    1997-01-01

    Neutral currents induced matter oscillations of electroweak-active (anti-)neutrinos to sterile neutrinos can explain the observed motion of pulsars. In contrast to a recently proposed explanation of the pulsar birth velocities based on the electron to tau (muon) neutrino oscillations [hep-ph/9606428], the heaviest neutrino (either active or sterile) would have to have mass of order several keV.

  15. Intranasal vaccination of recombinant H5N1 HA1 proteins fused with foldon and Fc induces strong mucosal immune responses with neutralizing activity: Implication for developing novel mucosal influenza vaccines.

    Science.gov (United States)

    Yu, Fei; Li, Ye; Guo, Yan; Wang, Lili; Yang, Jie; Zhao, Guangyu; Zhou, Yusen; Du, Lanying; Jiang, Shibo

    2015-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 virus remains a threat to public health because of its continued spread in poultry in some countries and its ability to infect humans with high mortality rate, calling for the development of effective and safe vaccines against H5N1 infection. Here, we constructed 4 candidate vaccines by fusing H5N1 hemagglutinin 1 (HA1) with foldon (HA1-Fd), human IgG Fc (HA1-Fc), foldon and Fc (HA1-FdFc) or His-tag (HA1-His). We then compared their ability to induce mucosal immune responses and neutralizing antibodies in the presence or absence of Poly(I:C) and CpG adjuvants via the intranasal route. Without an adjuvant, HA1-FdFc could elicit appreciable humoral immune responses and local mucosal IgA antibodies in immunized mice, while other vaccine candidates only induced background immune responses. In the presence of Poly(I:C) and CpG, both HA1-Fd and HA1-Fc elicited much higher levels of serum IgG and local mucosal IgA antibodies than HA1-His. Poly(I:C) and CpG could also augment the neutralizing antibody responses induced by these 4 vaccine candidates in the order of HA1-FdFc > HA1-Fc > HA1-Fd > HA1-His. These results suggest that both Fd and Fc potentiate the immunogenicity of the recombinant HA1 protein and that Poly(I:C) and CpG serve as efficient mucosal adjuvants in promoting efficacy of these vaccine candidates to induce strong systemic and local antibody responses and potent neutralizing antibodies, providing a useful strategy to develop effective and safe mucosal H5N1 vaccines.

  16. Predictive mapping using GIS to locate epithermal gold deposits at Cabo de Gata (Prov. of Almeria, Spain); Cartografia predictiva mediante SIG de depositos epitermales de oro en Cabo de Gata, Almeria, Espana

    Energy Technology Data Exchange (ETDEWEB)

    Rogol-Sanchez, J. P.; Chica-Olmo, M.; Rodriguez-Galiano, V.; Pardo-Iguzquiza, E.

    2011-07-01

    The main aim of mineral potential mapping is to generate predictive maps showing the spatial distribution of a numerical index of favour ability for the presence of a mineral deposit of the type sought. We have studied the mineral favorability for epithermal gold deposits in the Cabo de Gata volcanic field in the Province of Almeria in Spain. Predictive maps deriving from the models suggest the presence of several potentially favourable zones. The performance of predictive maps is similar in most cases. Nevertheless, data-driven methods are able to capture more readily the spatial distribution of known gold occurrences in the area. (Author) 32 refs.

  17. A New Age of Constructivism: "Mode Neutral"

    Science.gov (United States)

    Reed, Peter; Smith, Brian; Sherratt, Cathy

    2008-01-01

    This article presents work in progress exploring social constructivism within Mode Neutral, and how various conditions impact upon the student experience. Mode Neutral's three dimensions--curriculum design, the role of the tutor and communication for learning--are affected by the conditions that can vary in any given context. The authors realise…

  18. 6 CFR 27.305 - Neutral adjudications.

    Science.gov (United States)

    2010-01-01

    ... 6 Domestic Security 1 2010-01-01 2010-01-01 false Neutral adjudications. 27.305 Section 27.305 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CHEMICAL FACILITY ANTI-TERRORISM STANDARDS Orders and Adjudications § 27.305 Neutral adjudications. (a) Any facility or other person who has...

  19. 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

  20. Neutral Vlasov kinetic theory of magnetized plasmas

    NARCIS (Netherlands)

    C. Tronci; E. Camporeale (Enrico)

    2014-01-01

    htmlabstractThe low-frequency limit of Maxwell equations is considered in the Maxwell-Vlasov system. This limit produces a neutral Vlasov system that captures essential features of plasma dynamics, while neglecting radiation effects. Euler-Poincar\\'e reduction theory is used to show that the neutral

  1. Neutral Vlasov kinetic theory of magnetized plasmas.

    NARCIS (Netherlands)

    C. Tronci; E. Camporeale (Enrico)

    2015-01-01

    htmlabstractThe low-frequency limit of Maxwell equations is considered in the Maxwell-Vlasov system. This limit produces a neutral Vlasov system that captures essential features of plasma dynamics, while neglecting radiation effects. Euler-Poincar\\'e reduction theory is used to show that the neutral

  2. The case for ecological neutral theory

    NARCIS (Netherlands)

    Rosindell, James; Hubbell, Stephen P.; He, Fangliang; Harmon, Luke J.; Etienne, Rampal S.

    Ecological neutral theory has elicited strong opinions in recent years. Here, we review these opinions and strip away some unfortunate problems with semantics to reveal three major underlying questions. Only one of these relates to neutral theory and the importance of ecological drift, whereas the

  3. Net neutrality and inflation of traffic

    NARCIS (Netherlands)

    Peitz, M.; Schütt, Florian

    Under strict net neutrality Internet service providers (ISPs) are required to carry data without any differentiation and at no cost to the content provider. We provide a simple framework with a monopoly ISP to evaluate the short-run effects of different net neutrality rules. Content differs in its

  4. Net Neutrality and Inflation of Traffic

    NARCIS (Netherlands)

    Peitz, M.; Schütt, F.

    2015-01-01

    Under strict net neutrality Internet service providers (ISPs) are required to carry data without any differentiation and at no cost to the content provider. We provide a simple framework with a monopoly ISP to evaluate different net neutrality rules. Content differs in its sensitivity to delay.

  5. 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 related...

  6. Tax Neutrality on International Capital Investments

    Directory of Open Access Journals (Sweden)

    Gizem KAPUCU

    2017-07-01

    Full Text Available The tax policies which states follow with regard to developing technology and capital investments with raising mobility due to globalism are need to be discussed in its legal basis. The principle of tax neutrality has the aim of being legal foundation for these policies. According to this, the neutrality principle in taxation of international capital investments is provided with two measures, namely; not effecting the investment decision and not discriminate between investments. In this paper, initially focused on the conceptual framework and the foundations of the tax neutrality principle and later capital export neutrality and capital import neutrality are considered and explained with regard to international capital movements. Moreover, conformity and diversion to the principle of the current situation and regulations in OECD, EU and Turkey are examined.

  7. A Trade Study of Thermosphere Empirical Neutral Density Models

    Science.gov (United States)

    Lin, C. S.; Cable, S. B.; Sutton, E. K.

    2014-12-01

    Accurate orbit prediction of space objects critically relies on modeling of thermospheric neutral density that determines drag force. In a trade study we have investigated a methodology to assess performances of neutral density models in predicting orbit against a baseline orbit trajectory. We use a metric defined as along-track error in a day a satellite is predicted to have for a given neutral density model when compared to its GPS positions. A set of ground truth data including Gravity Recovery and Climate Experiment (GRACE) accelerometer and GPS data, solar radio F10.7 proxy and magnetic activity measurements are used to calculate the baseline orbit. This approach is applied to compare the daily along-track errors among HASDM, JB08, MSISE-00 and DTM-2012 neutral density models. The dynamically calibrated HASDM model yields a daily along-track error close to the baseline error and lower than the other empirical models. Among the three empirical models (JB08, MSISE-00 and DTM-2012) the MSISE-00 model has produced the smallest daily along-track error. The results suggest that the developed metric and methodology could be used to assess overall errors in orbit prediction expected from empirical density models. They have also been adapted in an analysis tool Satellite Orbital Drag Error Estimator (SODEE) to estimate orbit prediction errors.

  8. Feline Immunodeficiency Virus (FIV Neutralization: A Review

    Directory of Open Access Journals (Sweden)

    Margaret J. Hosie

    2011-10-01

    Full Text Available One of the major obstacles that must be overcome in the design of effective lentiviral vaccines is the ability of lentiviruses to evolve in order to escape from neutralizing antibodies. The primary target for neutralizing antibodies is the highly variable viral envelope glycoprotein (Env, a glycoprotein that is essential for viral entry and comprises both variable and conserved regions. As a result of the complex trimeric nature of Env, there is steric hindrance of conserved epitopes required for receptor binding so that these are not accessible to antibodies. Instead, the humoral response is targeted towards decoy immunodominant epitopes on variable domains such as the third hypervariable loop (V3 of Env. For feline immunodeficiency virus (FIV, as well as the related human immunodeficiency virus-1 (HIV-1, little is known about the factors that lead to the development of broadly neutralizing antibodies. In cats infected with FIV and patients infected with HIV-1, only rarely are plasma samples found that contain antibodies capable of neutralizing isolates from other clades. In this review we examine the neutralizing response to FIV, comparing and contrasting with the response to HIV. We ask whether broadly neutralizing antibodies are induced by FIV infection and discuss the comparative value of studies of neutralizing antibodies in FIV infection for the development of more effective vaccine strategies against lentiviral infections in general, including HIV-1.

  9. Net Neutrality: Media Discourses and Public Perception

    Directory of Open Access Journals (Sweden)

    Christine Quail

    2010-01-01

    Full Text Available This paper analyzes media and public discourses surrounding net neutrality, with particular attention to public utility philosophy, from a critical perspective. The article suggests that further public education about net neutrality would be beneficial. The first portion of this paper provides a survey of the existing literature surrounding net neutrality, highlighting the contentious debate between market-based and public interest perspectives. In order to contextualize the debate, an overview of public utility philosophy is provided, shedding light on how the Internet can be conceptualized as a public good. Following this discussion, an analysis of mainstream media is presented, exploring how the media represents the issue of net neutrality and whether or not the Internet is discussed through the lens of public utility. To further examine how the net neutrality debate is being addressed, and to see the potential impacts of media discourses on the general public, the results of a focus group are reported and analyzed. Finally, a discussion assesses the implications of the net neutrality debate as presented through media discourses, highlighting the future of net neutrality as an important policy issue.

  10. Redox-neutral rhodium-catalyzed C-H functionalization of arylamine N-oxides with diazo compounds: primary C(sp(3))-H/C(sp(2))-H activation and oxygen-atom transfer.

    Science.gov (United States)

    Zhou, Bing; Chen, Zhaoqiang; Yang, Yaxi; Ai, Wen; Tang, Huanyu; Wu, Yunxiang; Zhu, Weiliang; Li, Yuanchao

    2015-10-05

    An unprecedented rhodium(III)-catalyzed regioselective redox-neutral annulation reaction of 1-naphthylamine N-oxides with diazo compounds was developed to afford various biologically important 1H-benzo[g]indolines. This coupling reaction proceeds under mild reaction conditions and does not require external oxidants. The only by-products are dinitrogen and water. More significantly, this reaction represents the first example of dual functiaonalization of unactivated a primary C(sp(3) )H bond and C(sp(2) )H bond with diazocarbonyl compounds. DFT calculations revealed that an intermediate iminium is most likely involved in the catalytic cycle. Moreover, a rhodium(III)-catalyzed coupling of readily available tertiary aniline N-oxides with α-diazomalonates was also developed under external oxidant-free conditions to access various aminomandelic acid derivatives by an O-atom-transfer reaction. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. 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

  12. Spheromak Energy Transport Studies via Neutral Beam Injection

    Energy Technology Data Exchange (ETDEWEB)

    McLean, H S; Hill, D N; Wood, R D; Jayakumar, J; Pearlstein, L D

    2008-02-11

    Results from the SSPX spheromak experiment provide strong motivation to add neutral beam injection (NBI) heating. Such auxiliary heating would significantly advance the capability to study the physics of energy transport and pressure limits for the spheromak. This LDRD project develops the physics basis for using NBI to heat spheromak plasmas in SSPX. The work encompasses three activities: (1) numerical simulation to make quantitative predictions of the effect of adding beams to SSPX, (2) using the SSPX spheromak and theory/modeling to develop potential target plasmas suitable for future application of neutral beam heating, and (3) developing diagnostics to provide the measurements needed for transport calculations. These activities are reported in several publications.

  13. Temporal and spatial distribution of alteration, mineralization and fluid inclusions in the transitional high-sulfidation epithermal-porphyry copper system at Red Mountain, Arizona

    Science.gov (United States)

    Lecumberri-Sanchez, Pilar; Newton, M. Claiborne; Westman, Erik C.; Kamilli, Robert J.; Canby, Vertrees M.; Bodnar, Robert J.

    2013-01-01

    Red Mountain, Arizona, is a Laramide porphyry Cu system (PCD) that has experienced only a modest level of erosion compared to most other similar deposits in the southwestern United States. As a result, the upper portion of the magmatic–hydrothermal system, which represents the transition from shallower high-sulfidation epithermal mineralization to deeper porphyry Cu mineralization, is well preserved. Within the Red Mountain system, alteration, mineralization and fluid inclusion assemblages show a systematic distribution in both time and space. Early-potassic alteration (characterized by the minerals biotite and magnetite) is paragenetically earlier than late-potassic alteration (K-feldspar–anhydrite) and both are followed by later phyllic (sericite–pyrite) alteration. Advanced argillic alteration (pyrophyllite–alunite–other clay minerals) is thought to be coeval with or postdate phyllic alteration. Minerals characteristic of advanced argillic alteration are present in the near surface. Phyllic alteration extends to greater depths compared to advanced argillic alteration. Early-potassic and late-potassic alteration are only observed in the deepest part of the system. Considerable overlap of phyllic alteration with both early-potassic and late-potassic alteration zones is observed. The hypogene mineralization contains 0.4–1.2% Cu and is spatially and temporally related to the late-potassic alteration event. Molybdenum concentration is typically In the deepest part of the system, an early generation of low-to-moderate density and salinity liquid + vapor inclusions with opaque daughter minerals is followed in time by halite-bearing inclusions that also contain opaque daughter minerals indicating that an early intermediate-density magmatic fluid evolved to a high-density, high-salinity mineralizing fluid. The increase in density and salinity of fluids with time observed in the deeper parts of the system may be the result of immiscibility (“boiling”) of

  14. Mineralogy and geochemical environment of formation of the Perama Hill high-sulfidation epithermal Au-Ag-Te-Se deposit, Petrota Graben, NE Greece

    Science.gov (United States)

    Voudouris, Panagiotis Christos; Melfos, Vasilios; Spry, Paul G.; Moritz, Robert; Papavassiliou, Constantinos; Falalakis, George

    2011-11-01

    The Perama Hill deposit is a high-sulfidation Au-Ag-Te-Se epithermal system hosted in silicic- and argillic altered andesitic rocks and overlying sandstones, which were emplaced on the eastern margin of the Petrota graben, northeastern Greece. The deposit evolved from an early stage silica-pyrite rock and argillic alteration followed by the deposition of sulfide-, sulfosalt- and telluride-bearing quartz-barite veins and stockworks. Early ore formation is characterized by a high-sulfidation-type enargite-galena-bearing ore assemblage (consisting of enargite, watanabeite, Fe-free sphalerite, covellite, kesterite, bismuthinite, selenian bismuthinite, lillianite homologues, kawazulite-tetradymite, goldfieldite, and native gold), followed by the formation of an intermediate-sulfidation-type tennantite-bearing assemblage characterized by ferrian/zincian tennantite, tellurobismuthite, tetradymite, melonite, native tellurium, Au-Ag-tellurides (calaverite, krennerite, sylvanite, hessite, petzite, stützite), altaite and electrum. Quartz, barite, kaolinite, sericite and minor aluminum-phosphate-sulfate minerals are gangue minerals. Fluid inclusion data demonstrate that the ore system evolved from an initial high temperature (up to 330°C) and low salinity (up to 4.9 wt.% NaCl equiv.) fluid towards a cooler (200°C) and very low salinity (0.7 wt.% NaCl equiv.) hydrothermal fluid suggesting progressive cooling and dilution of the ore fluid. The ore minerals at Perama Hill reflect variable fS2 and fTe2 conditions during base and precious metal deposition. Early ore deposition took place at ~300°C, at log fS2 values between ≈-8.2 and -5.5, and log fTe2 from -11.8 and -7.8. Late ore deposition occurred at log fS2 = -11.8 to -9.8 and log fTe2 of ≈-9.2 and -7.8. These data and paragenetic studies indicate a shift towards higher log fTe2 and lower log fS2 and log fSe2 values for the mineralizing fluids with time. The kawazulite/tetradymitess-gold association at Perama Hill

  15. Neutral-neutral and neutral-ion collision integrals for Y2O3-Ar plasma system

    Science.gov (United States)

    Dhamale, Gayatri D.; Nath, Swastik; Mathe, Vikas L.; Ghorui, Srikumar

    2017-06-01

    A detailed investigation on the neutral-neutral and neutral-ion collision integrals is reported for Y2O3-Ar plasma, an important system of functional material with unique properties having a wide range of processing applications. The calculated integrals are indispensible pre-requisite for the estimation of transport properties needed in CFD modelling of associated plasma processes. Polarizability plays an important role in determining the integral values. Ambiguity in selecting appropriate polarizability data available in the literature and calculating effective number of electrons in the ionized species contributing to the polarizability are addressed. The integrals are evaluated using Lennard-Jones like phenomenological potential up to (l,s) = (4,4). Used interaction potential is suitable for both neutral-neutral and neutral-ion interactions. For atom-parent ion interactions, contribution coming from the inelastic resonant charge transfer process has been accounted properly together with that coming from the elastic counterpart. A total of 14 interacting species and 60 different interactions are considered. Key contributing factors like basic electronic properties of the interacting species and associated polarizability values are accounted carefully. Adopted methodology is first benchmarked against data reported in the literature and then applied to the Y2O3-Ar plasma system for estimating the collision integrals. Results are presented in the temperature range of 100 K-100 000 K.

  16. The buffer effect in neutral electrolyte supercapacitors

    Science.gov (United States)

    Vindt, Steffen T.; Skou, Eivind M.

    2016-02-01

    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 change in the redox potential of water in opposite directions on the two electrodes, resulting in the wider stability window. The magnitude of this effect is suggested to be dependent on the buffer capacity, rather than the intrinsic pH value of the electrolyte. This is confirmed by studying the impact 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, aqueous potassium nitrate as the electrolyte and potassium phosphates as the buffer system.

  17. Recombinant Sheep Pox Virus Proteins Elicit Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Olga V. Chervyakova

    2016-06-01

    Full Text Available The aim of this work was to evaluate the immunogenicity and neutralizing activity of sheep pox virus (SPPV; genus Capripoxvirus, family Poxviridae structural proteins as candidate subunit vaccines to control sheep pox disease. SPPV structural proteins were identified by sequence homology with proteins of vaccinia virus (VACV strain Copenhagen. Four SPPV proteins (SPPV-ORF 060, SPPV-ORF 095, SPPV-ORF 117, and SPPV-ORF 122, orthologs of immunodominant L1, A4, A27, and A33 VACV proteins, respectively, were produced in Escherichia coli. Western blot analysis revealed the antigenic and immunogenic properties of SPPV-060, SPPV-095, SPPV-117 and SPPV-122 proteins when injected with adjuvant into experimental rabbits. Virus-neutralizing activity against SPPV in lamb kidney cell culture was detected for polyclonal antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins. To our knowledge, this is the first report demonstrating the virus-neutralizing activities of antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins.

  18. Recombinant Sheep Pox Virus Proteins Elicit Neutralizing Antibodies.

    Science.gov (United States)

    Chervyakova, Olga V; Zaitsev, Valentin L; Iskakov, Bulat K; Tailakova, Elmira T; Strochkov, Vitaliy M; Sultankulova, Kulyaisan T; Sandybayev, Nurlan T; Stanbekova, Gulshan E; Beisenov, Daniyar K; Abduraimov, Yergali O; Mambetaliyev, Muratbay; Sansyzbay, Abylay R; Kovalskaya, Natalia Y; Nemchinov, Lev G; Hammond, Rosemarie W

    2016-06-07

    The aim of this work was to evaluate the immunogenicity and neutralizing activity of sheep pox virus (SPPV; genus Capripoxvirus, family Poxviridae) structural proteins as candidate subunit vaccines to control sheep pox disease. SPPV structural proteins were identified by sequence homology with proteins of vaccinia virus (VACV) strain Copenhagen. Four SPPV proteins (SPPV-ORF 060, SPPV-ORF 095, SPPV-ORF 117, and SPPV-ORF 122), orthologs of immunodominant L1, A4, A27, and A33 VACV proteins, respectively, were produced in Escherichia coli. Western blot analysis revealed the antigenic and immunogenic properties of SPPV-060, SPPV-095, SPPV-117 and SPPV-122 proteins when injected with adjuvant into experimental rabbits. Virus-neutralizing activity against SPPV in lamb kidney cell culture was detected for polyclonal antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins. To our knowledge, this is the first report demonstrating the virus-neutralizing activities of antisera raised to SPPV-060, SPPV-117, and SPPV-122 proteins.

  19. Heparanase-neutralizing antibodies attenuate lymphoma tumor growth and metastasis

    Science.gov (United States)

    Weissmann, Marina; Arvatz, Gil; Horowitz, Netanel; Feld, Sari; Naroditsky, Inna; Zhang, Yi; Ng, Mary; Hammond, Edward; Nevo, Eviatar; Vlodavsky, Israel; Ilan, Neta

    2016-01-01

    Heparanase is an endoglycosidase that cleaves heparan sulfate side chains of proteoglycans, resulting in disassembly of the extracellular matrix underlying endothelial and epithelial cells and associating with enhanced cell invasion and metastasis. Heparanase expression is induced in carcinomas and sarcomas, often associating with enhanced tumor metastasis and poor prognosis. In contrast, the function of heparanase in hematological malignancies (except myeloma) was not investigated in depth. Here, we provide evidence that heparanase is expressed by human follicular and diffused non-Hodgkin's B-lymphomas, and that heparanase inhibitors restrain the growth of tumor xenografts produced by lymphoma cell lines. Furthermore, we describe, for the first time to our knowledge, the development and characterization of heparanase-neutralizing monoclonal antibodies that inhibit cell invasion and tumor metastasis, the hallmark of heparanase activity. Using luciferase-labeled Raji lymphoma cells, we show that the heparanase-neutralizing monoclonal antibodies profoundly inhibit tumor load in the mouse bones, associating with reduced cell proliferation and angiogenesis. Notably, we found that Raji cells lack intrinsic heparanase activity, but tumor xenografts produced by this cell line exhibit typical heparanase activity, likely contributed by host cells composing the tumor microenvironment. Thus, the neutralizing monoclonal antibodies attenuate lymphoma growth by targeting heparanase in the tumor microenvironment. PMID:26729870

  20. Modeling Neutral Hydrogen in the HSX Stellarator

    Science.gov (United States)

    Stephey, L.; Bader, A.; Anderson, D. T.; Talmadge, J. N.; Hegna, C.; Anderson, F. S. B.

    2012-10-01

    Efforts to improve the understanding of neutral hydrogen in the HSX stellarator are ongoing. The DEGAS code [1], a fully 3D Monte-Carlo neutral particle code, is used to simulate neutral particle density and synthetic H-alpha emission in HSX. DEGAS simulations are compared to EMC3-EIRENE [2] simulations in an effort to understand the similarities and differences in how each code predicts neutral physics in the unique HSX geometry and relatively low operating density. Additionally, experimentally motivated DEGAS simulations are presented of a supersonic gas injection system that will be installed on HSX. Finally, simulations of many different wall recycling scenarios are presented in an effort to develop a plasma wall interaction model that more closely matches experimental H-alpha measurements.[4pt] [1] D. B. Heifetz et al, J. Comp. Phys. Vol. 46 (1982) p. 309.[0pt] [2] Y. Feng et al, Contribution Plasma Physics, 44 1-3 (2004) p. 57-69.

  1. 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.

  2. CP violation in the neutral kaon system

    Energy Technology Data Exchange (ETDEWEB)

    Brod, Joachim [TTP, Uni Karlsruhe (Germany); Gorbahn, Martin [TU Muenchen, IAS (Germany)

    2009-07-01

    The parameter {epsilon}{sub K} describes CP violation in the mixing of neutral K-mesons. It is an important ingredient in the standard analysis of the unitarity triangle. Recent progress in the lattice calculation of B{sub K}, parameterising the long distance effects in neutral Kaon mixing, have made a NNLO calculation of the short distance contributions mandatory. I discuss this calculation and present first results.

  3. Diamagnetism and neutrals depletion in a plasma

    Science.gov (United States)

    Fruchtman, Amnon; Shinohara, Shunjiro

    2017-10-01

    Recent experimental and theoretical findings [Shinohara et al., Phys. Plasmas 23, 122108 (2016)] regarding the pressure balance between a cylindrical plasma, an axial magnetic field, and neutral gas are explored further theoretically. The length of the cylinder is assumed much larger than its radius, so that axial losses are small and cross-field transport is dominant. Conditions for either magnetic pressure or neutral pressure balancing the plasma pressure and an associated coupling parameter, which were identified in the above-mentioned recent study, are examined further. In addition, a second coupling parameter is identified which determines which is larger, the relative change in the magnetic field or the relative change in neutral density. An unexpected nonmonotonic variation of the plasma density with the plasma particle flux is demonstrated. It is shown that for plasma beta close to unity, as plasma generation and plasma particle flux increase, the plasma density surprisingly decreases. This decrease follows a decrease in plasma confinement due to an increased plasma diamagnetism. The effect of the magnetic field on neutral depletion is examined. It is shown that an increase in the magnetic field as the plasma density is kept constant results in a decrease in neutral depletion, while an increase in the magnetic field as the plasma particle flux is kept constant results in constant neutral depletion.

  4. Amino Acid Changes in the HIV-1 gp41 Membrane Proximal Region Control Virus Neutralization Sensitivity

    Directory of Open Access Journals (Sweden)

    Todd Bradley

    2016-10-01

    Full Text Available Most HIV-1 vaccines elicit neutralizing antibodies that are active against highly sensitive (tier-1 viruses or rare cases of vaccine-matched neutralization-resistant (tier-2 viruses, but no vaccine has induced antibodies that can broadly neutralize heterologous tier-2 viruses. In this study, we isolated antibodies from an HIV-1-infected individual that targeted the gp41 membrane-proximal external region (MPER that may have selected single-residue changes in viral variants in the MPER that resulted in neutralization sensitivity to antibodies targeting distal epitopes on the HIV-1 Env. Similarly, a single change in the MPER in a second virus from another infected-individual also conferred enhanced neutralization sensitivity. These gp41 single-residue changes thus transformed tier-2 viruses into tier-1 viruses that were sensitive to vaccine-elicited tier-1 neutralizing antibodies. These data demonstrate that Env amino acid changes within the MPER bnAb epitope of naturally-selected escape viruses can increase neutralization sensitivity to multiple types of neutralizing antibodies, and underscore the critical importance of the MPER for maintaining the integrity of the tier-2 HIV-1 trimer.

  5. Analysis of memory B cell responses and isolation of novel monoclonal antibodies with neutralizing breadth from HIV-1-infected individuals.

    Directory of Open Access Journals (Sweden)

    Davide Corti

    2010-01-01

    Full Text Available The isolation of human monoclonal antibodies (mAbs that neutralize a broad spectrum of primary HIV-1 isolates and the characterization of the human neutralizing antibody B cell response to HIV-1 infection are important goals that are central to the design of an effective antibody-based vaccine.We immortalized IgG(+ memory B cells from individuals infected with diverse clades of HIV-1 and selected on the basis of plasma neutralization profiles that were cross-clade and relatively potent. Culture supernatants were screened using various recombinant forms of the envelope glycoproteins (Env in multiple parallel assays. We isolated 58 mAbs that were mapped to different Env surfaces, most of which showed neutralizing activity. One mAb in particular (HJ16 specific for a novel epitope proximal to the CD4 binding site on gp120 selectively neutralized a multi-clade panel of Tier-2 HIV-1 pseudoviruses, and demonstrated reactivity that was comparable in breadth, but distinct in neutralization specificity, to that of the other CD4 binding site-specific neutralizing mAb b12. A second mAb (HGN194 bound a conserved epitope in the V3 crown and neutralized all Tier-1 and a proportion of Tier-2 pseudoviruses tested, irrespective of clade. A third mAb (HK20 with broad neutralizing activity, particularly as a Fab fragment, recognized a highly conserved epitope in the HR-1 region of gp41, but showed striking assay-dependent selectivity in its activity.This study reveals that by using appropriate screening methods, a large proportion of memory B cells can be isolated that produce mAbs with HIV-1 neutralizing activity. Three of these mAbs show unusual breadth of neutralization and therefore add to the current panel of HIV-1 neutralizing antibodies with potential for passive protection and template-based vaccine design.

  6. Achieving Carbon Neutrality in the Global Aluminum Industry

    Science.gov (United States)

    Das, Subodh

    2012-02-01

    In the 21st century, sustainability is widely regarded as the new corporate culture, and leading manufacturing companies (Toyota, GE, and Alcoa) and service companies (Google and Federal Express) are striving towards carbon neutrality. The current carbon footprint of the global aluminum industry is estimated at 500 million metric tonnes carbon dioxide equivalent (CO2eq), representing about 1.7% of global emissions from all sources. For the global aluminum industry, carbon neutrality is defined as a state where the total "in-use" CO2eq saved from all products in current use, including incremental process efficiency improvements, recycling, and urban mining activities, equals the CO2eq expended to produce the global output of aluminum. This paper outlines an integrated and quantifiable plan for achieving "carbon neutrality" in the global aluminum industry by advocating five actionable steps: (1) increase use of "green" electrical energy grid by 8%, (2) reduce process energy needs by 16%, (3) deploy 35% of products in "in-use" energy saving applications, (4) divert 6.1 million metric tonnes/year from landfills, and (5) mine 4.5 million metric tonnes/year from aluminum-rich "urban mines." Since it takes 20 times more energy to make aluminum from bauxite ore than to recycle it from scrap, the global aluminum industry could set a reasonable, self-imposed energy/carbon neutrality goal to incrementally increase the supply of recycled aluminum by at least 1.05 metric tonnes for every tonne of incremental production via primary aluminum smelter capacity. Furthermore, the aluminum industry can and should take a global leadership position by actively developing internationally accepted and approved carbon footprint credit protocols.

  7. Characterization of the Wild-Type and Truncated Forms of a Neutral GH10 Xylanase from Coprinus cinereus: Roles of C-Terminal Basic Amino Acid-Rich Extension in Its SDS Resistance, Thermostability, and Activity.

    Science.gov (United States)

    Hu, Hang; Chen, Kaixiang; Li, Lulu; Long, Liangkun; Ding, Shaojun

    2017-04-28

    A neutral xylanase (CcXyn) was identified from Coprinus cinereus. It has a single GH10 catalytic domain with a basic amino acid-rich extension (PVRRK) at the C-terminus. In this study, the wild-type (CcXyn) and C-terminus-truncated xylanase (CcXyn-Δ5C) were heterologously expressed in Pichia pastoris and their characteristics were comparatively analyzed with aims to examine the effect of this extension on the enzyme function. The circular dichorism analysis indicated that both enzymes in general had a similar structure, but CcXyn-Δ5C contained less α-helices (42.9%) and more random coil contents (35.5%) than CcXyn (47.0% and 32.8%, respectively). Both enzymes had the same pH (7.0) and temperature (45°C) optima, and similar substrate specificity on different xylans. They all hydrolyzed beechwood xylan primarily to xylobiose and xylotriose. The amounts of xylobiose and xylotriose accounted for 91.5% and 92.2% (w/w) of total xylooligosaccharides (XOS) generated from beechwood by CcXyn and CcXyn-Δ5C, respectively. However, truncation of the C-terminal 5-amino-acids extension significantly improved the thermostability, SDS resistance, and pH stability at pH 6.0-9.0. Furthermore, CcXyn-Δ5C exhibited a much lower Km value than CcXyn (0.27 mg/ml vs 0.83 mg/ml), and therefore, the catalytic efficiency of CcXyn-Δ5C was 2.4-times higher than that of CcXyn. These properties make CcXyn-Δ5C a good model for the structure-function study of (α/β)8-barrel-folded enzymes and a promising candidate for various applications, especially in the detergent industry and XOS production.

  8. Intermediate sulfidation epithermal mineralization of No. 4 anomaly of Golojeh deposit (N. Zanjan based on mineralography, alteration and ore fluid geochemistry features

    Directory of Open Access Journals (Sweden)

    Behzad Mehrab

    2014-04-01

    contents of galena, sphalerite and minor chalcopyrite and tennantite, low to moderate temperature and salinity of ore-bearing fluid, low depth of mineralization and Fe–bearing sphalerite features at the No. 4 anomaly of Golojeh deposit, are similar to those of intermediate sulfidation (IS epithermal base and precious metals vein–type deposit that probably might be related to Cu–Au porphyry system in depth.

  9. Neutral beamline with improved ion energy recovery

    Science.gov (United States)

    Dagenhart, William K.; Haselton, Halsey H.; Stirling, William L.; Whealton, John H.

    1984-01-01

    A neutral beamline generator with unneutralized ion energy recovery is provided which enhances the energy recovery of the full energy ion component of the beam exiting the neutralizer cell of the beamline. The unneutralized full energy ions exiting the neutralizer are deflected from the beam path and the electrons in the cell are blocked by a magnetic field applied transverse to the beamline in the cell exit region. The ions, which are generated at essentially ground potential and accelerated through the neutralizer cell by a negative acceleration voltage, are collected at ground potential. A neutralizer cell exit end region is provided which allows the magnetic and electric fields acting on the exiting ions to be closely coupled. As a result, the fractional energy ions exiting the cell with the full energy ions are reflected back into the gas cell. Thus, the fractional energy ions do not detract from the energy recovery efficiency of full energy ions exiting the cell which can reach the ground potential interior surfaces of the beamline housing.

  10. Sputtering of neutral and ionic indium clusters

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Z.; Coon, S.R.; Calaway, W.F.; Pellin, M.J.; Gruen, D.M.; Von Nagy-Felsobuki, E.I.

    1993-10-01

    Secondary neutral and secondary ion cluster yields were measured during the sputtering of a polycrystalline indium surface by normally incident {approximately}4 keV Ar{sup +} ions. In the secondary neutral mass spectra, indium clusters as large as In{sub 32} were observed. In the secondary ion mass spectra, indium clusters up to In{sub 18}{sup +} were recorded. Cluster yields obtained from both the neutral and ion channel exhibited a power law dependence on the number of constituent atoms, n, in the cluster, with the exponents measured to be {minus}5.6 and {minus}4. 1, respectively. An abundance drop was observed at n=8, 15, and 16 in both the neutral and ion yield distributions suggesting that the stability of the ion (either secondary ion or photoion) plays a significant role in the observed distributions. In addition, our experiments suggest that unimolecular decomposition of the neutral cluster may also plays an important role in the measured yield distributions.

  11. Neutralization sensitivity of HIV-1 subtype B' clinical isolates from former plasma donors in China.

    Science.gov (United States)

    OuYang, Yabo; Sun, Jianping; Huang, Yang; Lu, Lu; Xu, Weisi; Hu, Xintao; Hong, Kunxue; Jiang, Shibo; Shao, Yiming; Ma, Liying

    2013-01-05

    HIV-1 subtype B' isolates have been predominantly circulating in China. Their intra- and inter-subtype neutralization sensitivity to autologous and heterologous plasmas has not been well studied. Twelve HIV-1 B' clinical isolates obtained from patients were tested for their intra- and inter-subtype neutralization sensitivity to the neutralization antibodies in the plasmas from patients infected by HIV-1 B' and CRF07_BC subtypes, respectively. We found that the plasmas from the HIV-1 B'-infected patients could potently neutralize heterologous viruses of subtype B' with mean ID50 titer (1/x) of about 67, but they were not effective in neutralizing autologous viruses of subtype B' with mean ID50 titer (1/x) of about 8. The plasmas from HIV-1 CRF07_BC-infected patients exhibited weak inter-subtype neutralization activity against subtype B' viruses with ID50 titer (1/x) is about 22. The neutralization sensitivity of HIV-1 B' isolates was inversely correlated with the neutralizing activity of plasmas from HIV-1 B'-infected patients (Spearman's r = -0.657, P = 0.020), and with the number of potential N-glycosylation site (PNGS) in V1-V5 region (Spearman's r = -0.493, P = 0.034), but positively correlated with the viral load (Spearman's r = 0.629, P = 0.028). It had no correlation with the length of V1-V5 regions or the CD4+ T cell count. Virus AH259V has low intra-subtype neutralization sensitivity, it can be neutralized by 17b (IC50: 10μg/ml) and 447-52D (IC50: 1.6μg/ml), and the neutralizing antibodies (nAbs) in plasma AH259P are effective in neutralizing infection by the primary HIV-1 isolates with different subtypes with ID50 titers (1/x) in the range of 32-396. These findings suggest that the HIV-1 subtype B' viruses may mutate under the immune pressure, thus becoming resistant to the autologous nAbs, possibly by changing the number of PNGS in the V1-V5 region of the viral gp120. Some of primary HIV-1 isolates are able to induce both intra- and inter-subtype cross-neutralizing

  12. Sub-domains of ricin's B subunit as targets of toxin neutralizing and non-neutralizing monoclonal antibodies.

    Directory of Open Access Journals (Sweden)

    Anastasiya Yermakova

    Full Text Available The B subunit (RTB of ricin toxin is a galactose (Gal-/N-acetylgalactosamine (GalNac-specific lectin that mediates attachment, entry, and intracellular trafficking of ricin in host cells. Structurally, RTB consists of two globular domains with identical folding topologies. Domains 1 and 2 are each comprised of three homologous sub-domains (α, β, γ that likely arose by gene duplication from a primordial carbohydrate recognition domain (CRD, although only sub-domains 1α and 2γ retain functional lectin activity. As part of our ongoing effort to generate a comprehensive B cell epitope map of ricin, we report the characterization of three new RTB-specific monoclonal antibodies (mAbs. All three mAbs, JB4, B/J F9 and C/M A2, were initially identified based on their abilities to neutralize ricin in a Vero cell cytotoxicity assay and to partially (or completely block ricin attachment to cell surfaces. However, only JB4 proved capable of neutralizing ricin in a macrophage apoptosis assay and in imparting passive immunity to mice in a model of systemic intoxication. Using a combination of techniques, including competitive ELISAs, pepscan analysis, differential reactivity by Western blot, as well as affinity enrichment of phage displayed peptides, we tentatively localized the epitopes recognized by the non-neutralizing mAbs B/J F9 and C/M A2 to sub-domains 2α and 2β, respectively. Furthermore, we propose that the epitope recognized by JB4 is within sub-domain 2γ, adjacent to RTB's high affinity Gal/GalNAc CRD. These data suggest that recognition of RTB's sub-domains 1α and 2γ are critical determinants of antibody neutralizing activity and protective immunity to ricin.

  13. But some neutrally stable strategies are more neutrally stable than others

    NARCIS (Netherlands)

    van Veelen, M.

    2010-01-01

    For games in which there is no evolutionarily stable strategy, it can be useful to look for neutrally stable ones. In extensive form games for instance there is typically no evolutionary stable strategy, while there may very well be a neutrally stable one. Such strategies can however still be

  14. Defensins Potentiate a Neutralizing Antibody Response to Enteric Viral Infection.

    Directory of Open Access Journals (Sweden)

    Anshu P Gounder

    2016-03-01

    Full Text Available α-defensins are abundant antimicrobial peptides with broad, potent antibacterial, antifungal, and antiviral activities in vitro. Although their contribution to host defense against bacteria in vivo has been demonstrated, comparable studies of their antiviral activity in vivo are lacking. Using a mouse model deficient in activated α-defensins in the small intestine, we show that Paneth cell α-defensins protect mice from oral infection by a pathogenic virus, mouse adenovirus 1 (MAdV-1. Survival differences between mouse genotypes are lost upon parenteral MAdV-1 infection, strongly implicating a role for intestinal defenses in attenuating pathogenesis. Although differences in α-defensin expression impact the composition of the ileal commensal bacterial population, depletion studies using broad-spectrum antibiotics revealed no effect of the microbiota on α-defensin-dependent viral pathogenesis. Moreover, despite the sensitivity of MAdV-1 infection to α-defensin neutralization in cell culture, we observed no barrier effect due to Paneth cell α-defensin activation on the kinetics and magnitude of MAdV-1 dissemination to the brain. Rather, a protective neutralizing antibody response was delayed in the absence of α-defensins. This effect was specific to oral viral infection, because antibody responses to parenteral or mucosal ovalbumin exposure were not affected by α-defensin deficiency. Thus, α-defensins play an important role as adjuvants in antiviral immunity in vivo that is distinct from their direct antiviral activity observed in cell culture.

  15. Hyperthermal neutral beam sources for material processing.

    Science.gov (United States)

    Yoo, S J; Kim, D C; Joung, M; Kim, J S; Lee, B J; Oh, K S; Kim, K U; Kim, Y H; Kim, Y W; Choi, S W; Son, H J; Park, Y C; Jang, J-N; Hong, M P

    2008-02-01

    Hyperthermal neutral beams have a great potential for material processes, especially for etching and thin film deposition for semiconductor and display fabrication as well as deposition for various thin film applications. Plasma-induced damage during plasma etching is a serious problem for manufacturing deep submicron semiconductor devices and is expected to be a problem for future nanoscale devices. Thermal and plasma-induced damage is also problematic for thin film depositions such as transparent conductive oxide films on organic light emitting diodes or flexible displays due to high temperature processes in plasma environments. These problems can be overcome by damage-free and low-temperature processes with hyperthermal neutral beams. We will present the status of the hyperthermal neutral beam development and the applications, especially, in semiconductor and display fabrication and introduce potential applications of thin film growing for optoelectronic devices such as light emitting diodes.

  16. Abstinence and neutrality: development and diverse views.

    Science.gov (United States)

    Schachter, J

    1994-08-01

    Usually, Freud adopted a technical device for personal or practical reasons and only later formulated its theoretical basis. His conception of abstinence initially seemed designed to curb his own troublesome erotic countertransference. These speculations, while having no bearing on the clinical value of abstinence and related neutrality, do emphasise the necessity to assess their utility objectively, on the basis of clinical data. Diverse views of abstinence and neutrality persist in part because early inconsistencies in Freud's conceptions remain unresolved, and in part because these views are derived from the analyst's personality and character, are not based upon clinical data, but are buttressed by iteration. An approach to empirical assessment is suggested using multiple analyst-observers: (1) to develop reliable criteria for four analyst behaviours: abstinence, neutrality, gratification and suggestion; and (2) to evaluate enhancement or impairment of analytic work. Utilisation of this approach in the supervision of candidates would enhance analytic pedagogy and to some degree facilitate a research orientation in candidates.

  17. Internal structure of the geomagnetic neutral sheet.

    Science.gov (United States)

    Schindler, K.; Ness, N. F.

    1972-01-01

    A study of the internal structure of the neutral sheet in the geomagnetic tail has been made from data obtained by the NASA-GSFC magnetic-field experiment on the Explorer 34 spacecraft during its tail passage in the first half of 1968. The data used in the analysis are individual measurements of the vector magnetic field at 2.56-sec intervals. The experimental results consist of statistical studies of relevant properties of the magnetic field as a function of field magnitude. The results do not support nearly one-dimensional field models with characteristic lengths for field variation parallel to the neutral sheet much larger than the neutral-sheet width. The principal conclusion from the data points toward consistency with a quasi-periodic (possibly turbulent) structure with a tendency to formation of magnetic loops as one might expect from stability studies.

  18. Multiplicity Distributions and Charged-neutral Fluctuations

    CERN Document Server

    Nayak, Tapan K.; Agnihotri, A.; Ahammed, Z.; Angelis, A.L.S.; Antonenko, V.; Arefev, V.; Astakhov, V.; Avdeitchikov, V.; Awes, T.C.; Baba, P.V.K.S.; Badyal, S.K.; Baldine, A.; Barabach, L.; Barlag, C.; Bathe, S.; Batiounia, B.; Bernier, T.; Bhalla, K.B.; Bhatia, V.S.; Blume, C.; Bock, R.; Bohne, E.M.; Bucher, D.; Buijs, A.; Buis, E.J.; Busching, H.; Carlen, L.; Chalyshev, V.; Chattopadhyay, S.; Chenawi, K.E.; Cherbatchev, R.; Chujo, T.; Claussen, A.; Das, A.C.; Decowski, M.P.; Djordjadze, V.; Donni, P.; Doubovik, I.; Dubey, A.K.; Dutta Majumda, M.R.; Eliseev, S.; Enosawa, K.; Feldmann, H.; Foka, P.; Fokin, S.; Frolov, V.; Ganti, M.S.; Garpman, S.; Gavrishchuk, O.; Geurts, F.J.M.; Ghosh, T.K.; Glasow, R.; Gupta, S.K.; Guskov, B.; Gustafsson, H.A.; Gutbrod, H.H.; Higuchi, R.; Hrivnacova, I.; Ippolitov, M.; Kalechofsky, H.; Kamermans, R.; Kampert, K.H.; Karadjev, K.; Karpio, K.; Kato, S.; Kees, S.; Kim, H.; Kolb, B.W.; Kosarev, I.; Koutcheryaev, I.; Kugler, A.; Kulinich, P.; Kumar, V.; Kurata, M.; Kurita, K.; Kuzmin, N.; Langbein, I.; Lebedev, A.; Lee, Y.Y.; Lohner, H.; Mahapatra, D.P.; Manko, V.; Martin, M.; Maximov, A.; Mehdiyev, Rashid R.; Mgebrichvili, G.; Miake, Y.; Mikhalev, D.; Mishra, G.C.; Miyamoto, Y.; Mohanty, B.; Morrison, Douglas R.O.; Mukhopadhyay, D.S.; Myalkovski, V.; Naef, H.; Nandi, B.K.; Nayak, S.K.; Nayak, T.K.; Neumaier, S.; Nianine, A.; Nikitine, V.; Nikolaev, S.; Nishimura, S.; Nomokov, P.; Nystrand, J.; Obenshain, F.E.; Oskarsson, A.; Otterlund, I.; Pachr, M.; Parfenov, A.; Pavliouk, S.; Peitzmann, T.; Petracek, V.; Plasil, F.; Purschke, M.L.; Raeven, B.; Rak, J.; Raniwala, R.; Raniwala, S.; Ramamurthy, V.S.; Rao, N.K.; Retiere, F.; Reygers, K.; Roland, G.; Rosselet, L.; Roufanov, I.; Rubio, J.M.; Sambyal, S.S.; Santo, R.; Sato, S.; Schlagheck, H.; Schmidt, H.R.; Shabratova, G.; Sibiriak, I.; Siemiarczuk, T.; Sinha, B.C.; Slavine, N.; Soderstrom, K.; Solomey, N.; Sood, G.; Sorensen, S.P.; Stankus, P.; Stefanek, G.; Steinberg, P.; Stenlund, E.; Stuken, D.; Sumbera, M.; Svensson, T.; Trivedi, M.D.; Tsvetkov, A.; Twenhofel, C.; Tykarski, L.; Urbahn, J.; van Eijndhoven, N.; van Heeringen, W.H.; van Nieuwenhuizen, G.J.; Vinogradov, A.; Viyogi, Y.P.; Vodopianov, A.S.; Voros, S.; Vos, M.A.; Wyslouch, B.; Yagi, K.; Yokota, Y.; Young, G.R.; Nayak, Tapan K.

    2001-01-01

    Results from the multiplicity distributions of inclusive photons and charged particles, scaling of particle multiplicities, event-by-event multiplicity fluctuations, and charged-neutral fluctuations in 158$\\cdot A$ GeV Pb+Pb collisions are presented and discussed. A scaling of charged particle multiplicity as $N_{part}^{1.07\\pm 0.05}$ and photons as $N_{part}^{1.12\\pm 0.03}$ have been observed, indicating violation of naive wounded nucleon model. The analysis of localized charged-neutral fluctuation indicates a model-independent demonstration of non-statistical fluctuations in both charged particles and photons in limited azimuthal regions. However, no correlated charged-neutral fluctuations are observed.

  19. 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.

  20. The net neutrality debate on Twitter

    Directory of Open Access Journals (Sweden)

    Wolf J. Schünemann

    2015-12-01

    Full Text Available The internet has been seen as a medium that empowers individual political actors in relation to established political elites and media gatekeepers. The present article discusses this “net empowerment hypothesis” and tests it empirically by analysing Twitter communication on the regulation of net neutrality. We extracted 503.839 tweets containing #NetNeutrality posted between January and March 2015 and analysed central developments and the network structure of the debate. The empirical results show that traditional actors from media and politics still maintain a central role.

  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. Cross-reactivity and phospholipase A{sub 2} neutralization of anti-irradiated Bothrops jararaca venom antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, P.J.; Nascimento, N. do; Paula, R.A. de; Cardi, B.A.; Rogero, J.R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    1995-12-31

    The detoxified Bothrops jararaca venom, immunized rabbits with the toxoid obtained and investigated cross-reactivity of the antibodies obtained against autologous and heterelogous venoms was presented. It was also investigated the ability of the IgGs, purified by affinity chromatography, from those sera to neutralize phospholipase. A{sub 2}, an ubiquous enzyme in animal venoms. Results indicate that venom irradiation leads to an attenuation of toxicity of 84%. Cross-reactivity was investigated by ELISA and Western blot and all venoms were reactive to the antibodies. On what refers to phospholipase A{sub 2} activity neutralization, the antibodies neutralized autologous venoms efficiently and, curiously, other venoms from the same genus were not neutralized, while Lachesis muta venom, a remote related specier, was neutralized by this serum. These data suggest that irradiation preserve important epitopes for induction of neutralizing antibodies and that these epitopes are not shared by all venoms assayed. (author). 8 refs, 2 figs, 3 tabs.

  3. Vesiculovirus Neutralization by Natural IgM and Complement

    Science.gov (United States)

    Tesfay, Mulu Z.; Ammayappan, Arun; Federspiel, Mark J.; Barber, Glen N.; Stojdl, David; Peng, Kah-Whye

    2014-01-01

    ABSTRACT Because of its very low human seroprevalence, vesicular stomatitis virus (VSV) has promise as a systemic oncolytic agent for human cancer therapy. However, as demonstrated in this report, the VSV infectious titer drops by 4 log units during the first hour of exposure to nonimmune human serum. This neutralization occurs relatively slowly and is mediated by the concerted actions of natural IgM and complement. Maraba virus, whose G protein is about 80% homologous to that of VSV, is relatively resistant to the neutralizing activity of nonimmune human serum. We therefore constructed and rescued a recombinant VSV whose G gene was replaced by the corresponding gene from Maraba virus. Comparison of the parental VSV and VSV with Maraba G substituted revealed nearly identical host range properties and replication kinetics on a panel of tumor cell lines. Moreover, in contrast to the parental VSV, the VSV with Maraba G substituted was resistant to nonimmune human serum. Overall, our data suggest that VSV with Maraba G substituted should be further investigated as a candidate for human systemic oncolytic virotherapy applications. IMPORTANCE Oncolytic virotherapy is a promising approach for the treatment of disseminated cancers, but antibody neutralization of circulating oncolytic virus particles remains a formidable barrier. In this work, we developed a pseudotyped vesicular stomatitis virus (VSV) with a glycoprotein of Maraba virus, a closely related but serologically distinct member of the family Rhabdoviridae, which demonstrated greatly diminished susceptibility to both nonimmune and VSV-immune serum neutralization. VSV with Maraba G substituted or lentiviral vectors should therefore be further investigated as candidates for human systemic oncolytic virotherapy and gene therapy applications. PMID:24648451

  4. Reconstitution and characterization of antibody repertoires of HIV-1-infected "elite neutralizers".

    Science.gov (United States)

    Sun, Zehua; Li, Jingjing; Hu, Xintao; Shao, Yiming; Zhang, Mei-Yun

    2015-06-01

    Around 3-5% HIV-1-infected individuals develop high titers of broadly neutralizing HIV-1 antibodies (bnAbs) during chronic infection. However, monoclonal antibodies (mAbs) isolated from such "elite neutralizers" do not, in most cases, depict the serum IgGs in neutralizing the virus. We hypothesize that HIV-1-specific antibodies in infected subjects may work in a population manner in containing the virus in vivo, and in vitro reconstituted antibody repertoires of "elite neutralizers" may mimic the sera in binding and neutralizing the virus. This study aims to investigate the antibody repertoires of three such "elite neutralizers" by reconstituting the immune antibody repertories in vitro followed by a comparative study of the recombinant library IgGs with the corresponding serum IgGs. We found that the recombinant library IgGs were much weaker than the serum IgGs in binding to envelope glycoproteins (Envs) and in neutralizing the virus and inhibiting Env-mediated cell-cell fusion. However, the sorted libraries composing of HIV-1-specific neutralizing antibodies (nAbs) in the three recombinant libraries exhibited comparable binding and inhibitory activities, as well as antibody-dependent cell-mediated cytotoxicity (ADCC), to the serum IgGs. The sorted library IgGs further showed neutralization profiles which are similar to those of the serum IgGs, but they were overall less potent than the serum IgGs. The sorted library IgGs and the serum IgGs bound weakly to the resurfaced Env gp120, RSC3, and did not bind to the CD4 binding site (CD4bs) knock-out mutant, ΔRSC3. Profiling with VRC01 binding site knock-out site mutants of gp120BaL indicates that, if there are any CD4bs bnAbs in these sera, they are more likely b12-like, but not VRC01-class bnAbs. Our results suggest that HIV-1-specific Ab-expressing B cells, especially potent nAb-expressing B cells may not be rich in the B cell repertoires of "elite neutralizers", but they may be highly active in producing nAbs in

  5. Cationic and Neutral Cp*M(NO)(κ2-Ph2PCH2CH2PPh2) Complexes of Molybdenum and Tungsten: Lewis-Acid-Induced Intramolecular C-H Activation.

    Science.gov (United States)

    Handford, Rex C; Wakeham, Russell J; Patrick, Brian O; Legzdins, Peter

    2017-03-20

    Treatment of CH2Cl2 solutions of Cp*M(NO)Cl2 (Cp* = η5-C5(CH3)5; M = Mo, W) first with 2 equiv of AgSbF6 in the presence of PhCN and then with 1 equiv of Ph2PCH2CH2PPh2 affords the yellow-orange salts [Cp*M(NO)(PhCN)(κ2-Ph2PCH2CH2PPh2)](SbF6)2 in good yields (M = Mo, W). Reduction of [Cp*M(NO)(PhCN)(κ2-Ph2PCH2CH2PPh2)](SbF6)2 with 2 equiv of Cp2Co in C6H6 at 80 °C produces the corresponding 18e neutral compounds, Cp*M(NO)(κ2-Ph2PCH2CH2PPh2) which have been isolated as analytically pure orange-red solids. The addition of 1 equiv of the Lewis acid, Sc(OTf)3, to solutions of Cp*M(NO)(κ2-Ph2PCH2CH2PPh2) at room temperature results in the immediate formation of thermally stable Cp*M(NO→Sc(OTf)3)(H)(κ3-(C6H4)PhPCH2CH2PPh2) complexes in which one of the phenyl substituents of the Ph2PCH2CH2PPh2 ligands has undergone intramolecular orthometalation. In a similar manner, addition of BF3 produces the analogous Cp*M(NO→BF3)(H)(κ3-(C6H4)PhPCH2CH2PPh2) complexes. In contrast, B(C6F5)3 forms the 1:1 Lewis acid-base adducts, Cp*M(NO→B(C6F5)3)(κ2-Ph2PCH2CH2PPh2) in CH2Cl2 at room temperature. Upon warming to 80 °C, Cp*Mo(NO→B(C6F5)3)(κ2-Ph2PCH2CH2PPh2) converts cleanly to the orthometalated product Cp*Mo(NO→B(C6F5)3)(H)(κ3-(C6H4)PhPCH2CH2PPh2), but Cp*W(NO→B(C6F5)3)(κ2-Ph2PCH2CH2PPh2) generates a mixture of products whose identities remain to be ascertained. Attempts to extend this chemistry to include related Ph2PCH2PPh2 compounds have had only limited success. All new complexes have been characterized by conventional spectroscopic and analytical methods, and the solid-state molecular structures of most of them have been established by single-crystal X-ray crystallographic analyses.

  6. How Objective a Neutral Word Is? A Neutrosophic Approach for the Objectivity Degrees of Neutral Words

    Directory of Open Access Journals (Sweden)

    Mihaela Colhon

    2017-11-01

    Full Text Available In the latest studies concerning the sentiment polarity of words, the authors mostly consider the positive and negative constructions, without paying too much attention to the neutral words, which can have, in fact, significant sentiment degrees. More precisely, not all the neutral words have zero positivity or negativity scores, some of them having quite important nonzero scores for these polarities. At this moment, in the literature, a word is considered neutral if its positive and negative scores are equal, which implies two possibilities: (1 zero positive and negative scores; (2 nonzero, but equal positive and negative scores. It is obvious that these cases represent two different categories of neutral words that must be treated separately by a sentiment analysis task. In this paper, we present a comprehensive study about the neutral words applied to English as is developed with the aid of SentiWordNet 3.0: the publicly available lexical resource for opinion mining. We designed our study in order to provide an accurate classification of the so-called “neutral words” described in terms of sentiment scores and using measures from neutrosophy theory. The intended scope is to fill the gap concerning the neutrality aspect by giving precise measurements for the words’ objectivity.

  7. IMPLEMENTASI PRINSIP NEUTRALITY DALAM PROSES MEDIASI

    Directory of Open Access Journals (Sweden)

    Lina Nur Anisa

    2015-04-01

    Full Text Available Mediasi merupakan salah satu bentuk alternatif penyelesaian sengketa di luar pengadilan. Gary Godpaster mengemukakan mediasi adalah proses negosiasi penyelesaian masalah atau sengketa dimana pihak ketiga atau pihak luar tidak memihak (impartial dan netral berkerja dengan pihak yang bersengketa untuk membantu mereka memperoleh kesepakatan perjanjian yang memuaskan. Mediasi mengantarkan para pihak pada perwujudan kesepakatan damai dengan menempatkan kedua belah pihak pada posisi yang sama, tidak ada pihak yang dimenangkan atau pihak yang dikalahkan (win-win solution. Dalam mediasi para pihak yang bersengketa pro aktif dan memiliki kewenangan penuh dalam pengambilan keputusan. Mediator tidak memiliki kewenangan dalam pengambilan keputusan, tetapi ia hanya membantu para pihak dalam menjaga proses mediasi guna mewujudkan kesepakatan damai mereka. Mediator harus memiliki sejumlah persyaratan dan keahlian (skill, yang akan membantunya mencari sejumlah kemungkinan penyelesaian sengketa. Neutrality (netralitas merupakan salah satu prinsip dari lima prinsip dasar yang ada dalam mediasi, kelima prinsip tersebut adalah prinsip kerahasiaan (confidentiality, sukarela (Volunteer, pemberdayaan (empowerment, netralitas (Neutrality, dan solusi yang unik (a unique solution. Kelima prinsip tersebut wajib dipahami oleh mediator, terlebih prinsip neutrality, mediator harus memahaminya secara menyeluruh dan sempurna. Kata Kunci: Mediasi, Mediator, Neutrality

  8. 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...

  9. 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.

  10. Educating for a Carbon Neutral Future

    DEFF Research Database (Denmark)

    Petersen, Mads Dines

    2014-01-01

    In the past decades the focus on first energy efficient architecture and later carbon neutral buildings has increased significantly. A part of this focus has started discussions about the design process and terms like integrated design has emerged from here, focusing on integrating the different...

  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...

  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. 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.

  14. Risk neutral second best toll pricing.

    Science.gov (United States)

    2011-08-01

    We propose a risk-neutral second best toll pricing scheme to account for the possible no uniqueness : of user equilibrium solutions. The scheme is designed to optimize for the expected objective value : as the UE solution varies within the solution s...

  15. A storage ring for neutral molecules

    NARCIS (Netherlands)

    Crompvoets, F.M.H.

    2005-01-01

    Time-varying inhomogeneous electric fields can be used to manipulate the motion of neutral molecules in phase-space, i.e., position-momentum space, via their electric dipole moment. A theoretical background is given on the motion of the molecules in phase-space. As the forces exerted on the

  16. CP violation in neutral kaon decays

    Energy Technology Data Exchange (ETDEWEB)

    Buchalla, G.

    1997-05-01

    A brief review of the theoretical status of CP violation in decays of neutral kaons is presented. We focus on three important topics: {epsilon}, {epsilon}`/{epsilon} and K{sub L}{yields}{pi}{sup 0}{nu}{anti {nu}}.

  17. 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.

  18. 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...

  19. Separation of Acids, Bases, and Neutral Compounds

    Science.gov (United States)

    Fujita, Megumi; Mah, Helen M.; Sgarbi, Paulo W. M.; Lall, Manjinder S.; Ly, Tai Wei; Browne, Lois M.

    2003-01-01

    Separation of Acids, Bases, and Neutral Compounds requires the following software, which is available for free download from the Internet: Netscape Navigator, version 4.75 or higher, or Microsoft Internet Explorer, version 5.0 or higher; Chime plug-in, version compatible with your OS and browser (available from MDL); and Flash player, version 5 or higher (available from Macromedia).

  20. 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…

  1. Neutral anion receptors: design and application

    NARCIS (Netherlands)

    Antonisse, M.M.G.; Reinhoudt, David

    1998-01-01

    After the development of synthetic cation receptors in the late 1960s, only in the past decade has work started on the development of synthetic neutral anion receptors. Combination and preorganization of different anion binding groups, like amides, urea moieties, or Lewis acidic metal centers lead

  2. 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

  3. Magnetoresistance Measurements of Graphene at the Charge Neutrality Point

    Science.gov (United States)

    Zhao, Yue; Cadden-Zimansky, Paul; Ghahari, Fereshte; Kim, Philip

    2012-03-01

    We report on transport measurements of the insulating state that forms at the charge neutrality point of graphene in a magnetic field. Using both conventional two-terminal measurements, sensitive to bulk and edge conductance, and Corbino measurements, sensitive only to the bulk conductance, we observed a vanishing conductance with increasing magnetic fields. By examining the resistance changes of this insulating state with varying perpendicular and in-plane fields, we probe the spin-active components of the excitations in total fields of up to 45 T. Our results indicate that the ν=0 quantum Hall state in single layer graphene is not spin-polarized.

  4. Study of neutral composition of lower thermosphere at Fort Churchill.

    Science.gov (United States)

    Nier, A. O.; Hickman, D. R.

    1973-01-01

    On Feb. 4 and 6, 1969, and May 11, 1970, Aerobee rockets carrying neutral mass spectrometers were flown at Fort Churchill, Canada during conditions of low geomagnetic activity. As in earlier flights at White Sands, New Mexico, each rocket carried both 'open' and 'closed' ion source instruments. Vertical profiles of N2, O2, O, Ar, and He were measured. Results obtained were essentially the same as those observed at White Sands except that for the winter flights helium appeared to be in diffusive equilibrium.

  5. DEGAS 2 neutral transport modeling of high density, low temperature plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stotler, D.P.; Karney, C.F.F. [Princeton Univ., NJ (United States). Princeton Plasma Physics Lab.; Pigarov, A.Y. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Plasma Fusion Center]|[I.V. Kurchatov Inst. of Atomic Energy, Moscow (Russian Federation)] [and others

    1997-05-01

    Neutral transport in the high density, low temperature plasma regime is examined using the DEGAS 2 Monte Carlo neutral transport code. DEGAS 2 is shown to agree with an analytic fluid neutral model valid in this regime as long as the grid cell spacing is less than twice the neutral mean-free path. Using new atomic physics data provided by the collisional radiative code CRAMD, DEGAS 2 is applied to a detached Alcator C-Mod discharge. A model plasma with electron temperature {approximately}1 eV along detached flux tubes, between the target and the ionization front, is used to demonstrate that recombination is essential to matching the experimental data. With the CRAMD data, {approximately}20% of the total recombination is due to molecular activated recombination.

  6. The receptor-binding site of the measles virus hemagglutinin protein itself constitutes a conserved neutralizing epitope.

    Science.gov (United States)

    Tahara, Maino; Ohno, Shinji; Sakai, Kouji; Ito, Yuri; Fukuhara, Hideo; Komase, Katsuhiro; Brindley, Melinda A; Rota, Paul A; Plemper, Richard K; Maenaka, Katsumi; Takeda, Makoto

    2013-03-01

    Here, we provide direct evidence that the receptor-binding site of measles virus (MV) hemagglutinin protein itself forms an effective conserved neutralizing epitope (CNE). Several receptor-interacting residues constitute the CNE. Thus, viral escape from neutralization has to be associated with loss of receptor-binding activity. Since interactions with both the signaling lymphocyte activation molecule (SLAM) and nectin4 are critical for MV pathogenesis, its escape, which results from loss of receptor-binding activity, should not occur in nature.

  7. [Neutralizing Monoclonal and Chimeric Antibodies to Human IFN-γ].

    Science.gov (United States)

    Larina, M V; Aliev, T K; Solopova, O N; Pozdnyakova, L P; Korobova, S V; Yakimov, S A; Sveshnikov, P G; Dolgikh, D A; Kirpichnikov, M P

    2015-01-01

    Autoiminune disorders are chronic diseases characterized by abnormal immune response directed against self-antigens that leads to tissue damage and violation of its normal functioning. Such diseases often result in disability or even death of patients. Nowadays a number of monoclonal antibodies to pro-inflammatory cytokines and their receptors are successfully used for the targeted treatment of autoimmune diseases. One of the perspective targets in autoimmune disease therapy is interferon gamma, a key cytokine in Th1 cells differentiation, activation of macrophages, and inflammation. In the present work, 5 monoclonal antibodies to human IFN-γ were obtained. For the development of potential therapeutic agent, we have performed neutralizing activity and affinity analysis of the antibodies. Based on the data obtained, the monoclonal antibody F1 was selected. This antibody has a dissociation constant 1.7 x 10(-9) M and IC90 = 8.9 ± 2.0 nM measured upon antibody inhibition of the IFN-γ-induced HLA-DR expression on the surface of U937 cells. We have constructed a bicistronic vector for the production of recombinant chimeric Fab fragment F1 chim in E. coli cells. The recombinant chimeric Fab fragment Fl chim neutralizes IFN-γ activity in vitro and has a dissociation constant 1.8 x 10(-9) M.

  8. Geology and geochemistry of epithermal precious metal vein systems in the intra-oceanic arcs of Palau and Yap, western Pacific

    Science.gov (United States)

    Rytuba, J.J.; Miller, W.R.

    1990-01-01

    The Palau and Yap arcs are part of an intra-oceanic island-arc-trench system which separates the Pacific and Philippine plates in the western Pacific Ocean. The 350-km-long Palau arc consists of over 200 islands while the 400-km-long Yap arc located to the north has only four major islands exposed. Four of the largest islands in Palau are composed primarily of early Eocene to mid-Miocene volcanic rocks and the four islands comprising Yap contain only Miocene volcanic rocks. Basalt and basaltic andesites of the Babelthuap Formation are the oldest volcanic rocks in Palau and are characterized by high MgO, Ni and Cr and low TiO2 and have a boninitic affinity. They form the central and southeastern parts of Babelthuap Island. Oligocene arc tholeiite flows having an age of 34-35.5 Ma comprise most of the three smaller volcanic islands in Palau and the western part of Babelthuap. The youngest volcanic rocks are dacitic intrusions having an age of 22.7-23.2 Ma. The Yap arc is unusual in that metamorphic rocks up to amphibolite grade form most of the islands. These are underlain by a melange composed of igneous and volcanic clasts as well as clasts from a dismembered copper-gold skarn deposit. Miocene volcanic rocks consisting of flows and volcaniclastic deposits overlie the melange and metamorphic complex. An epithermal precious-metal vein system hosted by flows and flow breccias of the Babelthuap Formation occurs in an area 1.5 km by 1 km on the southeast side of Babelthuap Island. Over 50 veins and mineralized breccias ranging up to 2 m in width and having a strike length up to 500 m contain from trace to 13.0 ppm gold. The veins consist of quartz with varying amounts of sulfides and iron oxides after sulfides and the mineralized breccias consist of brecciated country rock cemented by quartz and iron oxides after sulfides. The veins and mineralized breccias generally dip within 15?? of vertical and have two preferred orientations, north-northwest and north

  9. Applications and Implications of Neutral versus Non-neutral Markers in Molecular Ecology

    Directory of Open Access Journals (Sweden)

    Heather Kirk

    2011-06-01

    Full Text Available The field of molecular ecology has expanded enormously in the past two decades, largely because of the growing ease with which neutral molecular genetic data can be obtained from virtually any taxonomic group. However, there is also a growing awareness that neutral molecular data can provide only partial insight into parameters such as genetic diversity, local adaptation, evolutionary potential, effective population size, and taxonomic designations. Here we review some of the applications of neutral versus adaptive markers in molecular ecology, discuss some of the advantages that can be obtained by supplementing studies of molecular ecology with data from non-neutral molecular markers, and summarize new methods that are enabling researchers to generate data from genes that are under selection.

  10. Applications and implications of neutral versus non-neutral markers in molecular ecology

    National Research Council Canada - National Science Library

    Kirk, Heather; Freeland, Joanna R

    2011-01-01

    The field of molecular ecology has expanded enormously in the past two decades, largely because of the growing ease with which neutral molecular genetic data can be obtained from virtually any taxonomic group...

  11. Results on Intense Beam Focusing and Neutralization from the Neutralized Transport Experiment

    Science.gov (United States)

    Yu, Simon; Anders, Andre; Bieniosek, F. M.; Eylon, Shmuel; Henestroza, Enrique; Roy, Prabir; Shuman, Derek; Waldron, William L.; Houck, Tim; Sharp, William; Rose, Dave; Dale, Welch; Efthimion, Philip; Gilson, Eric; Sefkow, Adam

    2003-10-01

    In heavy ion inertial confinement fusion systems, intense beams of ions must be transported from the exit of the final focus magnet system through the target chamber to hit millimeter spot sizes on the target. Effective plasma neutralization of intense ion beams through the target chamber is essential for the viability of an economically competitive heavy ion fusion power plant. The physics of final magnetic transport and neutralized drift has been studied extensively with PIC simulations. To provide quantitative comparisons of theoretical predictions with experiment, the Heavy Ion Fusion Virtual National Laboratory has completed the construction and has begun experimentation with the NTX (Neutralized Transport Experiment). The experiment consists of 3 phases, each with physics issues of its own. Phase 1 is designed to generate a very high brightness potassium beam with variable perveance, using a beam aperturing technique. Phase 2 consists of magnetic transport through four pulsed quadrupoles. Here, beam tuning as well as the effects of phase space dilution through higher order nonlinear fields must be understood. In Phase 3, a converging ion beam at the exit of the magnetic section is transported through a drift section with plasma sources for beam neutralization, and the final spot size is measured under various conditions of neutralization. In this paper, we present results from all 3 phases of the experiment, with particular emphasis on the neutralization experiments.

  12. 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.

  13. [Expression and characterization of a neutral Enterobacter cloacae GX-3 invertase].

    Science.gov (United States)

    Zhao, Yingli; Wu, Qianqian; Zhang, Zhikai; Wang, Zilong; Wei, Yutuo; Huang, Ribo; Du, Liqin

    2015-04-04

    To characterize a neutral invertase from Enterobacter cloacae GX-3. By searching GenBank database, we found the genes encoding invertase from the same genus Enterobacter. These sequences were aligned and analyzed. Then, a gene encoding neutral invertase was amplified by PCR. The recombinant plasmid pQE-Einv was constructed. We purified the expressed protein Einv with nickel-nitrilotriacetic acid chromatography. At last, the characterics of the recombinant protein Einv were studied in detail. A gene encoding neutral invertase was discovered and cloned from E. cloacae GX-3. The recombinant enzyme Einv was characterized. Einv had an optimum pH of 6.5 and an optimum temperature of 40 degrees C. The results of sodium dodecyl sulfate polyacrylamide gel electropheresis (SDS-PAGE) and gel permeation chromatography ( GPC) showed that Einv was a homo-dimer protein. Einv retained 80% activity at sucrose concentrations up to 1170 mmol/L. But, Einv had no transglycosylation activity at high sucrose concentration. It could hydrolyze raffinose, 1-kestose, nystose, fructofuranosylnystose and stachyose. It is first reported that an invertase from Enterobacter cloacae is a beta-fructofuranosidase at neutral pH range. It only has hydrolysis activity without tranglycosylation activity. These characteristics indicate that the neutral invertase Einv has important applications in food industry.

  14. 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.

  15. 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.

  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. A new approach to entangling neutral atoms.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jongmin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Martin, Michael J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jau, Yuan-Yu [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Deutsch, Ivan H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Biedermann, Grant W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-11-01

    Our team has developed a new approach to entangling neutral atoms with a Rydberg-dressed interaction. Entangling neutral atoms is an essential key of quantum technologies such as quantum computation, many-body quantum simulation, and high-precision atomic sensors . The demonstrated Rydberg-dressed protocol involves adiabatically imposing a light shift on the ground state by coupling an excited Rydberg state with a tuned laser field. Using this technique, we have demonstrated a strong and tunable dipole - dipole interaction between two individually trapped atoms with energy shifts of order 1 MHz, which has been challenging to achieve in other protocols . During this program, we experimentally demonstrated Bell-state entanglement and the isomorphism to the Jaynes - Cumming model of a Rydberg-dressed two-atom system. Our theoretical calculations of a CPHASE quantum logic gate and arbitrary Dicke state quantum control in this system encourage further work.

  18. 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.

  19. Quasi-neutral theory of epidemic outbreaks.

    Directory of Open Access Journals (Sweden)

    Oscar A Pinto

    Full Text Available 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.

  20. 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.

  1. New Approach to Explain Neutrality of Money

    OpenAIRE

    Bandura, Alexander

    2017-01-01

    This paper presents a new explanation of neutrality of money in general case, regardless of the duration. It is based on the CMI-model of macroeconomic dynamics, which proposes the fundamental relationship between the efficiency of the use of production resources, money supply, inflation, and dynamics of the economic growth. This relationship is proved empirically by its testing on the examples of two completely different economies (the U.S. and Ukrainian ones). The testing period covers seve...

  2. Oscillations of neutral B mesons systems

    CERN Document Server

    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

  3. BNL negative ion based neutral beam development

    Energy Technology Data Exchange (ETDEWEB)

    Alessi, J.G.; Hershcovitch, A.; Kovarik, V.; Larson, R.A.; McKenzie-Wilson, R.; Prelec, K.; Sluyters, T.

    1981-01-01

    The BNL Neutral Beam Development Group has as its objective the development of neutral beam systems, using negative ion sources with high current density. In this past year we have made the transition from pulsed high current negative ion sources to sources designed to operate steady state. We are presently testing two dc sources, a magnetron source and a modified magnetron with plasma injection from a hollow cathode discharge (HCD). Both sources have operated with steady state discharges; to date 0.11A of H/sup -/ has been extracted from the standard magnetron while about 1A of H/sup -/ has been produced on a surface, but not extracted, in the HCD system. Present plans are to transport the beam from a 2A magnetron around a bending magnet, followed by dc acceleration of the beam to 200 keV. These units would be stacked to obtain higher currents. The HCD source is expected to operate at much lower pressures (10/sup -4/ - 10/sup -3/ Torr), and therefore close coupled acceleration of the beam to 200 keV is envisioned. This makes the source module considerably more compact. The MEQA-LAC, dc acceleration with periodic electrostatic quadrupole focusing, and the RFQ are being considered as ways to accelerate negative ion beams to energies above 200 keV. In the neutral beam line a novel plasma neutralizer is being considered which uses HCD's to feed a plasma into a solenoidal magnetic field. This should result in a high plasma density (10/sup 13/ - 10/sup 14/ cm/sup -3/) with a low background gas pressure.

  4. 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.

  5. 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.

  6. Atomic Transition Probabilities for Neutral Cerium

    Science.gov (United States)

    Lawler, J. E.; den Hartog, E. A.; Wood, M. P.; Nitz, D. E.; Chisholm, J.; Sobeck, J.

    2009-10-01

    The spectra of neutral cerium (Ce I) and singly ionized cerium (Ce II) are more complex than spectra of other rare earth species. The resulting high density of lines in the visible makes Ce ideal for use in metal halide (MH) High Intensity Discharge (HID) lamps. Inclusion of cerium-iodide in a lamp dose can improve both the Color Rendering Index and luminous efficacy of a MH-HID lamp. Basic spectroscopic data including absolute atomic transition probabilities for Ce I and Ce II are needed for diagnosing and modeling these MH-HID lamps. Recent work on Ce II [1] is now being augmented with similar work on Ce I. Radiative lifetimes from laser induced fluorescence measurements [2] on neutral Ce are being combined with emission branching fractions from spectra recorded using a Fourier transform spectrometer. A total of 14 high resolution spectra are being analyzed to determine branching fractions for 2000 to 3000 lines from 153 upper levels in neutral Ce. Representative data samples and progress to date will be presented. [4pt] [1] J. E. Lawler, C. Sneden, J. J. Cowan, I. I. Ivans, and E. A. Den Hartog, Astrophys. J. Suppl. Ser. 182, 51-79 (2009). [0pt] [2] E. A. Den Hartog, K. P. Buettner, and J. E. Lawler, J. Phys. B: Atomic, Molecular & Optical Physics 42, 085006 (7pp) (2009).

  7. A neutral model of transcriptome evolution.

    Directory of Open Access Journals (Sweden)

    Philipp Khaitovich

    2004-05-01

    Full Text Available Microarray technologies allow the identification of large numbers of expression differences within and between species. Although environmental and physiological stimuli are clearly responsible for changes in the expression levels of many genes, it is not known whether the majority of changes of gene expression fixed during evolution between species and between various tissues within a species are caused by Darwinian selection or by stochastic processes. We find the following: (1 expression differences between species accumulate approximately linearly with time; (2 gene expression variation among individuals within a species correlates positively with expression divergence between species; (3 rates of expression divergence between species do not differ significantly between intact genes and expressed pseudogenes; (4 expression differences between brain regions within a species have accumulated approximately linearly with time since these regions emerged during evolution. These results suggest that the majority of expression differences observed between species are selectively neutral or nearly neutral and likely to be of little or no functional significance. Therefore, the identification of gene expression differences between species fixed by selection should be based on null hypotheses assuming functional neutrality. Furthermore, it may be possible to apply a molecular clock based on expression differences to infer the evolutionary history of tissues.

  8. Kinetics of ion-ion mutual neutralization

    Science.gov (United States)

    Miller, Thomas M.; Wiens, Justin P.; Shuman, Nicholas S.; Viggiano, Albert A.

    2014-10-01

    We have measured rate coefficients for 87 mutual neutralization reactions between thermal energy anions and cations, a number of them as a function of temperature. In addition, in two cases we have observed a transfer ionization channel in which there is enough energy for the anion reactant to be doubly ionized, yielding a cation product rather than neutralization. We will summarize these results and note correlations, namely: (1) binary neutralization rate coefficients are primarily a function of the chemical nature of the system for atom-atom ionic pairs (with a wide range of rate coefficients), but quickly become dominated by physical aspects (i.e., relative velocity) as the number of atoms in the system increases. (2) Rate coefficients for atom-atom ionic pairs are well fit at 300 K by k = 3 × 10-4 Rx-3 . 15 , where Rx is the curve crossing radius given by Rx = 27.2/ ΔE, with ΔE being the electron transfer energy released in the reaction. (ΔE in eV, Rx in Bohr, and k in cm3/s.) (3) Rate coefficients for systems of more than 4 or 5 atoms are well described by k = 2.7 × 10-7 (T/300)- 0 . 9μ - 0 . 5 . (T in K, and the reduced mass μ in amu.) (4) Triatomic systems have rate coefficients smaller than given by the expression in (3). Supported by the Air Force Office of Scientific Research, AFOSR 2303EP.

  9. 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

  10. Recurrent Potent Human Neutralizing Antibodies to Zika Virus in Brazil and Mexico.

    Science.gov (United States)

    Robbiani, Davide F; Bozzacco, Leonia; Keeffe, Jennifer R; Khouri, Ricardo; Olsen, Priscilla C; Gazumyan, Anna; Schaefer-Babajew, Dennis; Avila-Rios, Santiago; Nogueira, Lilian; Patel, Roshni; Azzopardi, Stephanie A; Uhl, Lion F K; Saeed, Mohsan; Sevilla-Reyes, Edgar E; Agudelo, Marianna; Yao, Kai-Hui; Golijanin, Jovana; Gristick, Harry B; Lee, Yu E; Hurley, Arlene; Caskey, Marina; Pai, Joy; Oliveira, Thiago; Wunder, Elsio A; Sacramento, Gielson; Nery, Nivison; Orge, Cibele; Costa, Federico; Reis, Mitermayer G; Thomas, Neena M; Eisenreich, Thomas; Weinberger, Daniel M; de Almeida, Antonio R P; West, Anthony P; Rice, Charles M; Bjorkman, Pamela J; Reyes-Teran, Gustavo; Ko, Albert I; MacDonald, Margaret R; Nussenzweig, Michel C

    2017-05-04

    Antibodies to Zika virus (ZIKV) can be protective. To examine the antibody response in individuals who develop high titers of anti-ZIKV antibodies, we screened cohorts in Brazil and Mexico for ZIKV envelope domain III (ZEDIII) binding and neutralization. We find that serologic reactivity to dengue 1 virus (DENV1) EDIII before ZIKV exposure is associated with increased ZIKV neutralizing titers after exposure. Antibody cloning shows that donors with high ZIKV neutralizing antibody titers have expanded clones of memory B cells that express the same immunoglobulin VH3-23/VK1-5 genes. These recurring antibodies cross-react with DENV1, but not other flaviviruses, neutralize both DENV1 and ZIKV, and protect mice against ZIKV challenge. Structural analyses reveal the mechanism of recognition of the ZEDIII lateral ridge by VH3-23/VK1-5 antibodies. Serologic testing shows that antibodies to this region correlate with serum neutralizing activity to ZIKV. Thus, high neutralizing responses to ZIKV are associated with pre-existing reactivity to DENV1 in humans. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Acid neutralization of precipitation in Northern China.

    Science.gov (United States)

    Wang, Yuesi; Yu, Wenpeng; Pan, Yuepeng; Wu, Dan

    2012-02-01

    There is an increasing concern over the impact of human-related emissions on the acid precipitation in China. However, few measurements have been conducted so far to clarify the acid-neutralization of precipitation on a regional scale. Under a network of 10 sites across Northern China operated during a 3-year period from December 2007 to November 2010, a total of 1118 rain and snow samples were collected. Of this total, 28% was acid precipitation with pH acid samples, 53% were found heavily acidic with pH value below 5.0, indicating significantly high levels of acidification of precipitation. Most of the acidity of precipitation was caused by H2SO4 and HNO3, their relative contribution being 72% and 28%, respectively. However; the contribution of HNO3 to precipitation acidity will be enhanced due to the increasing NO(x) and stable SO2 emissions in future. Neutralization factors for K+, NH4+, Ca2+, Na+, and Mg2+ were estimated as 0.06, 0.71, 0.72, 0.15, and 0.13, respectively. The application of multiple regression analysis further quantified higher NH4+ and Ca2+ contribution to the neutralization process, but the dominant neutralizing agent varied from site to site. The neutralization was less pronounced in the rural than urban areas, probably due to different levels of alkaline species, which strongly buffered the acidity. Presence of high concentrations of basic ions was mainly responsible for high pH of precipitation with annual volume-weighted mean (VWM) values larger than 5.6 at several sites. It was estimated that in the absence of buffering ions, for the given concentration of SO4(2-) and NO3-, the annual VWM pH of precipitation would have been recorded around 3.5 across Northern China. This feature suggested that emissions of particles and gaseous NH3 played very important role in controlling the spatial variations of pH of precipitation in the target areas.

  12. Broadly Neutralizing Antibody Responses in a Large Longitudinal Sub-Saharan HIV Primary Infection Cohort.

    Directory of Open Access Journals (Sweden)

    Elise Landais

    2016-01-01

    Full Text Available Broadly neutralizing antibodies (bnAbs are thought to be a critical component of a protective HIV vaccine. However, designing vaccines immunogens able to elicit bnAbs has proven unsuccessful to date. Understanding the correlates and immunological mechanisms leading to the development of bnAb responses during natural HIV infection is thus critical to the design of a protective vaccine. The IAVI Protocol C program investigates a large longitudinal cohort of primary HIV-1 infection in Eastern and South Africa. Development of neutralization was evaluated in 439 donors using a 6 cross-clade pseudo-virus panel predictive of neutralization breadth on larger panels. About 15% of individuals developed bnAb responses, essentially between year 2 and year 4 of infection. Statistical analyses revealed no influence of gender, age or geographical origin on the development of neutralization breadth. However, cross-clade neutralization strongly correlated with high viral load as well as with low CD4 T cell counts, subtype-C infection and HLA-A*03(- genotype. A correlation with high overall plasma IgG levels and anti-Env IgG binding titers was also found. The latter appeared not associated with higher affinity, suggesting a greater diversity of the anti-Env responses in broad neutralizers. Broadly neutralizing activity targeting glycan-dependent epitopes, largely the N332-glycan epitope region, was detected in nearly half of the broad neutralizers while CD4bs and gp41-MPER bnAb responses were only detected in very few individuals. Together the findings suggest that both viral and host factors are critical for the development of bnAbs and that the HIV Env N332-glycan supersite may be a favorable target for vaccine design.

  13. Differences between Doppler velocities of ions and neutral atoms in a solar prominence

    Science.gov (United States)

    Anan, T.; Ichimoto, K.; Hillier, A.

    2017-05-01

    Context. In astrophysical systems with partially ionized plasma, the motion of ions is governed by the magnetic field while the neutral particles can only feel the magnetic field's Lorentz force indirectly through collisions with ions. The drift in the velocity between ionized and neutral species plays a key role in modifying important physical processes such as magnetic reconnection, damping of magnetohydrodynamic waves, transport of angular momentum in plasma through the magnetic field, and heating. Aims: This paper aims to investigate the differences between Doppler velocities of calcium ions and neutral hydrogen in a solar prominence to look for velocity differences between the neutral and ionized species. Methods: We simultaneously observed spectra of a prominence over an active region in H I 397 nm, H I 434 nm, Ca II 397 nm, and Ca II 854 nm using a high dispersion spectrograph of the Domeless Solar Telescope at Hida observatory. We compared the Doppler velocities, derived from the shift of the peak of the spectral lines presumably emitted from optically-thin plasma. Results: There are instances when the difference in velocities between neutral atoms and ions is significant, for example 1433 events ( 3% of sets of compared profiles) with a difference in velocity between neutral hydrogen atoms and calcium ions greater than 3σ of the measurement error. However, we also found significant differences between the Doppler velocities of two spectral lines emitted from the same species, and the probability density functions of velocity difference between the same species is not significantly different from those between neutral atoms and ions. Conclusions: We interpreted the difference of Doppler velocities as being a result of the motions of different components in the prominence along the line of sight, rather than the decoupling of neutral atoms from plasma. The movie attached to Fig. 1 is available at http://www.aanda.org

  14. Affinity maturation to improve human monoclonal antibody neutralization potency and breadth against hepatitis C virus.

    Science.gov (United States)

    Wang, Yong; Keck, Zhen-yong; Saha, Anasuya; Xia, Jinming; Conrad, Fraser; Lou, Jianlong; Eckart, Michael; Marks, James D; Foung, Steven K H

    2011-12-23

    A potent neutralizing antibody to a conserved hepatitis C virus (HCV) epitope might overcome its extreme variability, allowing immunotherapy. The human monoclonal antibody HC-1 recognizes a conformational epitope on the HCV E2 glycoprotein. Previous studies showed that HC-1 neutralizes most HCV genotypes but has modest potency. To improve neutralization, we affinity-matured HC-1 by constructing a library of yeast-displayed HC-1 single chain Fv (scFv) mutants, using for selection an E2 antigen from one of the poorly neutralized HCVpp. We developed an approach by parallel mutagenesis of the heavy chain variable (VH) and κ-chain variable (Vk) genes separately, then combining the optimized VH and Vk mutants. This resulted in the generation of HC-1-related scFv variants exhibiting improved affinities. The best scFv variant had a 92-fold improved affinity. After conversion to IgG1, some of the antibodies exhibited a 30-fold improvement in neutralization activity. Both surface plasmon resonance and solution kinetic exclusion analysis showed that the increase in affinity was largely due to a lowering of the dissociation rate constant, Koff. Neutralization against a panel of HCV pseudoparticles and infectious 2a HCV virus improved with the affinity-matured IgG1 antibodies. Interestingly, some of these antibodies neutralized a viral isolate that was not neutralized by wild-type HC-1. Moreover, propagating 2a HCVcc under the selective pressure of WT HC-1 or affinity-matured HC-1 antibodies yielded no viral escape mutants and, with the affinity-matured IgG1, needed 100-fold less antibody to achieve complete virus elimination. Taken together, these findings suggest that affinity-matured HC-1 antibodies are excellent candidates for therapeutic development.

  15. Broadly-Reactive Neutralizing and Non-neutralizing Antibodies Directed against the H7 Influenza Virus Hemagglutinin Reveal Divergent Mechanisms of Protection.

    Directory of Open Access Journals (Sweden)

    Gene S Tan

    2016-04-01

    Full Text Available In the early spring of 2013, Chinese health authorities reported several cases of H7N9 influenza virus infections in humans. Since then the virus has established itself at the human-animal interface in Eastern China and continues to cause several hundred infections annually. In order to characterize the antibody response to the H7N9 virus we generated several mouse monoclonal antibodies against the hemagglutinin of the A/Shanghai/1/13 (H7N9 virus. Of particular note are two monoclonal antibodies, 1B2 and 1H5, that show broad reactivity to divergent H7 hemagglutinins. Monoclonal antibody 1B2 binds to viruses of the Eurasian and North American H7 lineages and monoclonal antibody 1H5 reacts broadly to virus isolates of the Eurasian lineage. Interestingly, 1B2 shows broad hemagglutination inhibiting and neutralizing activity, while 1H5 fails to inhibit hemagglutination and demonstrates no neutralizing activity in vitro. However, both monoclonal antibodies were highly protective in an in vivo passive transfer challenge model in mice, even at low doses. Experiments using mutant antibodies that lack the ability for Fc/Fc-receptor and Fc/complement interactions suggest that the protection provided by mAb 1H5 is, at least in part, mediated by the Fc-fragment of the mAb. These findings highlight that a protective response to a pathogen may not only be due to neutralizing antibodies, but can also be the result of highly efficacious non-neutralizing antibodies not readily detected by classical in vitro neutralization or hemagglutination inhibition assays. This is of interest because H7 influenza virus vaccines induce only low hemagglutination inhibiting antibody titers while eliciting robust antibody titers as measured by ELISA. Our data suggest that these binding but non-neutralizing antibodies contribute to protection in vivo.

  16. 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. Copyright © 2016. Published by Elsevier B.V.

  17. Network Neutrality : A Survey of the Economic Literature

    NARCIS (Netherlands)

    Schuett, F.

    2010-01-01

    This paper reviews the small but growing economic literature on network neutrality. It considers a number of possible departures from network neutrality, in particular termination fees, second-degree price discrimination, and vertical foreclosure.

  18. 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

    2014-01-01

    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

  19. Building concepts for a transition towards energy neutrality in 2050

    Energy Technology Data Exchange (ETDEWEB)

    De Boer, B.J.; Paauw, J. [TNO Built Environment and Geosciences, Delft (Netherlands); Opstelten, I.J.; Bakker, E.J. [Energy research Centre of the Netherlands ECN, Petten (Netherlands)

    2007-03-15

    In this paper building concepts for the near future are described which enable the transition towards a net energy neutral building sector in the Netherlands by the year 2050. With 'net energy neutrality' is meant that, on a yearly basis, the total energy consumption in the built environment is compensated by local renewable energy production e.g. by using solar thermal (T), photovoltaic (PV), PVT and/or wind. A study concerning the feasibility of a 'net energy neutral built environment by 2050' set the energetic ambitions for the building concepts to be developed. This resulted in different concepts for residential buildings and for office-buildings. The building concepts are based on passive house technology to minimise the heating and cooling demand, and make optimal use of active and passive solar energy. Concepts for new to build domestic buildings are in fact energy producing to compensate for the remaining energy demand of existing, renovated dwellings. In all concepts the 'trias energetica' or 'energy pyramid' served as a general guideline, striving for minimisation of energy demand, maximal usage of renewable energy and usage of fossil fuels as efficiently as possible. Different full roof integrated options for using solar energy (PV, T or PVT) with variable storage options have been compared by making simulations with a dynamic simulation programme, to gain insight on their impact on energy, building engineering and economic impact. Also different possibilities for installations to fulfil the heating demand for the space heating and DHW demand are compared. For each concept, the resulting primary energy profiles for space heating and cooling, domestic hot water, electricity consumption for lighting, ventilation and household appliances are given.

  20. Human monoclonal antibodies broadly neutralizing against influenza B virus.

    Directory of Open Access Journals (Sweden)

    Mayo Yasugi

    2013-02-01

    Full Text Available Influenza virus has the ability to evade host immune surveillance through rapid viral genetic drift and reassortment; therefore, it remains a continuous public health threat. The development of vaccines producing broadly reactive antibodies, as well as therapeutic strategies using human neutralizing monoclonal antibodies (HuMAbs with global reactivity, has been gathering great interest recently. Here, three hybridoma clones producing HuMAbs against influenza B virus, designated 5A7, 3A2 and 10C4, were prepared using peripheral lymphocytes from vaccinated volunteers, and were investigated for broad cross-reactive neutralizing activity. Of these HuMAbs, 3A2 and 10C4, which recognize the readily mutable 190-helix region near the receptor binding site in the hemagglutinin (HA protein, react only with the Yamagata lineage of influenza B virus. By contrast, HuMAb 5A7 broadly neutralizes influenza B strains that were isolated from 1985 to 2006, belonging to both Yamagata and Victoria lineages. Epitope mapping revealed that 5A7 recognizes 316G, 318C and 321W near the C terminal of HA1, a highly conserved region in influenza B virus. Indeed, no mutations in the amino acid residues of the epitope region were induced, even after the virus was passaged ten times in the presence of HuMAb 5A7. Moreover, 5A7 showed significant therapeutic efficacy in mice, even when it was administered 72 hours post-infection. These results indicate that 5A7 is a promising candidate for developing therapeutics, and provide insight for the development of a universal vaccine against influenza B virus.

  1. Maternal Neutralization-Resistant Virus Variants Do Not Predict Infant HIV Infection Risk.

    Science.gov (United States)

    Milligan, Caitlin; Omenda, Maxwel M; Chohan, Vrasha; Odem-Davis, Katherine; Richardson, Barbra A; Nduati, Ruth; Overbaugh, Julie

    2016-02-02

    Mother-to-child transmission (MTCT) of HIV provides a setting for studying immune correlates of protection. Neutralizing antibodies (NAbs) are suggested to contribute to a viral bottleneck during MTCT, but their role in blocking transmission is unclear, as studies comparing the NAb sensitivities of maternal viruses have yielded disparate results. We sought to determine whether transmitting mothers differ from nontransmitting mothers in the ability to neutralize individual autologous virus variants present at transmission. Ten transmitting and 10 nontransmitting HIV-infected mothers at high risk of MTCT were included in this study. Full-length HIV envelope genes (n = 100) were cloned from peripheral blood mononuclear cells obtained near transmission from transmitting mothers and at similar time points from nontransmitting mothers. Envelope clones were tested as pseudoviruses against contemporaneous, autologous maternal plasma in neutralization assays. The association between transmission and the log2 50% inhibitory concentration (IC50) for multiple virus variants per mother was estimated by using logistic regression with clustered standard errors. t tests were used to compare proportions of neutralization-resistant viruses. Overall, transmitting mothers had a median IC50 of 317 (interquartile range [IQR], 202 to 521), and nontransmitting mothers had a median IC50 of 243 (IQR, 95 to 594). Transmission risk was not significantly associated with autologous NAb activity (odds ratio, 1.25; P = 0.3). Compared to nontransmitting mothers, transmitting mothers had similar numbers of or fewer neutralization-resistant virus variants, depending on the IC50 neutralization resistance cutoff. In conclusion, HIV-infected mothers harbor mostly neutralization-sensitive viruses, although resistant variants were detected in both transmitting and nontransmitting mothers. These results suggest that MTCT during the breastfeeding period is not driven solely by the presence of maternal

  2. Neutralization of cobra venom by cocktail antiserum against venom proteins of cobra (Naja naja naja).

    Science.gov (United States)

    Venkatesan, C; Sarathi, M; Balasubramanaiyan, G; Vimal, S; Madan, N; Sundar Raj, N; Mohammed Yusuf Bilal, S; Nazeer Basha, A; Farook, M A; Sahul Hameed, A S; Sridevi, G

    2014-01-01

    Naja naja venom was characterized by its immunochemical properties and electrophoretic pattern which revealed eight protein bands (14 kDa, 24 kDa, 29 kDa, 45 kDa, 48 kDa, 65 kDa, 72 kDa and 99 kDa) by SDS-PAGE in reducing condition after staining with Coomassie Brilliant Blue. The results showed that Naja venom presented high lethal activity. Whole venom antiserum or individual venom protein antiserum (14 kDa, 29 kDa, 65 kDa, 72 kDa and 99 kDa) of venom could recognize N. naja venom by Western blotting and ELISA, and N. naja venom presented antibody titer when assayed by ELISA. The neutralization tests showed that the polyvalent antiserum neutralized lethal activities by both in vivo and in vitro studies using mice and Vero cells. The antiserum could neutralize the lethal activities in in-vivo and antivenom administered after injection of cobra venom through intraperitoneal route in mice. The cocktail antiserum also could neutralize the cytotoxic activities in Vero cell line by MTT and Neutral red assays. The results of the present study suggest that cocktail antiserum neutralizes the lethal activities in both in vitro and in vivo models using the antiserum against cobra venom and its individual venom proteins serum produced in rabbits. Copyright © 2013 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  3. 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{\

  4. Influence of Neutralization Attitude in Academic Dishonesty among Undergraduates

    Science.gov (United States)

    Meng, Chan Ling; Othman, Jamilah; D'Silva, Jeffrey Lawrence; Omar, Zoharah

    2014-01-01

    Previous literature had proposed that individuals tend to use neutralization to motivate their decisions to engage in deviant behaviours. This indicated that even though students have strong motivations not to cheat may do so anyway after employing neutralizing strategies. Hence, this study attempted to examine the role of neutralization in…

  5. Neutralizing capacity of a new monovalent anti-Bothrops atrox antivenom: comparison with two commercial antivenoms

    Directory of Open Access Journals (Sweden)

    R. Otero

    1997-03-01

    Full Text Available Three horse-derived antivenoms were tested for their ability to neutralize lethal, hemorrhagic, edema-forming, defibrinating and myotoxic activities induced by the venom of Bothrops atrox from Antioquia and Chocó (Colombia. The following antivenoms were used: a polyvalent (crotaline antivenom produced by Instituto Clodomiro Picado (Costa Rica, b monovalent antibothropic antivenom produced by Instituto Nacional de Salud-INS (Bogotá, and c a new monovalent anti-B. atrox antivenom produced with the venom of B. atrox from Antioquia and Chocó. The three antivenoms neutralized all toxic activities tested albeit with different potencies. The new monovalent anti-B. atrox antivenom showed the highest neutralizing ability against edema-forming and defibrinating effects of B. atrox venom (41 ± 2 and 100 ± 32 µl antivenom/mg venom, respectively, suggesting that it should be useful in the treatment of B. atrox envenomation in Antioquia and Chocó

  6. Spatial location of neutralizing and non-neutralizing B cell epitopes on domain 1 of ricin toxin's binding subunit.

    Directory of Open Access Journals (Sweden)

    Yinghui Rong

    Full Text Available Ricin toxin's binding subunit (RTB is a galactose-/N-acetylgalactosamine (Gal/GalNac-specific lectin that mediates uptake and intracellular trafficking of ricin within mammalian cells. Structurally, RTB consists of two globular domains, each divided into three homologous sub-domains (α, β, γ. In this report, we describe five new murine IgG monoclonal antibodies (mAbs against RTB: MH3, 8A1, 8B3, LF1, and LC5. The mAbs have similar binding affinities (KD for ricin holotoxin, but displayed a wide range of in vitro toxin-neutralizing activities. Competition ELISAs indicate that the two most potent toxin-neutralizing mAbs (MH3, 8A1, as well as one of the moderate toxin-neutralizing mAbs (LF1, recognize distinct epitopes near the low affinity Gal recognition domain in RTB subdomain 1α. Evaluated in a mouse model of systemic ricin challenge, all five mAbs afforded some benefit against intoxication, but only MH3 was protective. However, neither MH3 nor 24B11, another well-characterized mAb against RTB subdomain 1α, could passively protect mice against a mucosal (intranasal ricin challenge. This is in contrast to SylH3, a previously characterized mAb directed against an epitope near RTB's high affinity Gal/GalNac recognition element in sub-domain 2γ, which protected animals against systemic and mucosal ricin exposure. SylH3 was significantly more effective than MH3 and 24B11 at blocking ricin attachment to host cell receptors, suggesting that mucosal immunity to ricin is best imparted by antibodies that target RTB's high affinity Gal/GalNac recognition element in subdomain 2γ, not the low affinity Gal recognition domain in subdomain 1α.

  7. Communication: Classical threshold law for ion-neutral-neutral three-body recombination

    Energy Technology Data Exchange (ETDEWEB)

    Pérez-Ríos, Jesús; Greene, Chris H. [Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907 (United States)

    2015-07-28

    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.

  8. ABOUT TAX NEUTRALITY AND NON-DISCRIMINATION

    Directory of Open Access Journals (Sweden)

    Ioan Dan Morar

    2012-07-01

    Full Text Available Taxpayers are required to pay taxes to the state budget by virtue of their position subject to the state, the latter in its capacity as sovereign person of public law. This quality gives them the right to impose against taxpayers by administrative means known, or sometimes with justice, respecting a certain extent the principles and traditions specific to tax. Principles of neutrality and non-discrimination are relevant in terms of describing the relations between public authorities and taxpayers. Although taxpayers are divided into official and legal persons, in fact individuals are those who support the ultimate tax burden.

  9. Targets for a Neutral Kaon Beam

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Christopher [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-04-01

    A secondary beam of neutral Kaons is under consideration for Hall D at Jefferson Lab to perform spectroscopic studies of hyperons produced by K 0 L particles scattering from proton and deuteron targets. The proposed physics program would utilize the GlueX detector package currently installed in Hall D. This contribution looks at potential targets for use in the new facility, paying close attention to the existing infrastructure of GlueX and Hall D. Unpolarized cryotargets of liquid hydrogen and deuerium, as well as polarized solid targets of protons and deuterons are examined.

  10. Large neutral amino acids in daily practice

    DEFF Research Database (Denmark)

    Ahring, Kirsten Kiær

    2010-01-01

    At the Kennedy Centre for Phenylketonuria, Denmark, large neutral amino acids (LNAAs) are being used to treat adult and adolescent patients who are nonadherent to dietary treatment for phenylketonuria (PKU). At the start of treatment, a patient must undergo dietary analysis and regular blood...... sampling to measure plasma amino acid (AA) concentrations. The aim of this analysis and treatment is that the patient receives 25-30% of the daily protein requirement from LNAA supplementation and the remaining 70-75% from natural, low-phenylalanine proteins (although some patients have difficulties...

  11. Toxic emissions and devaluated CO2-neutrality

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    Environmental, energy and climate policies need fresh reflections. In order to evaluate toxics reduction policies the Stockholm Convention on Persistent Organic Pollutants is mandatory. Denmark's function as lead country for dioxin research in the context of the OSPAR Convention is contrasted...... with a climate policy whose goals of CO2-reduction were made operational by green-wash. Arguments are given for the devaluation of CO2- neutrality in case of burning wood. Alternative practices as storing C in high quality wood products and/or leaving wood in the forest are recommended. A counter...

  12. Acid-base machines: electrical work from neutralization reactions.

    Science.gov (United States)

    Lima, Gilberto; Morais, William G; Gomes, Wellington J A S; Huguenin, Fritz

    2017-11-29

    We have developed an electrochemical system that performs electrical work due to changes in alkaline ion and proton activities associated with acidic solution neutralization. This system can be used to treat wastewater, contributing to sustainable growth. The system includes an electrochemical machine that operates between an acidic and a basic reservoir to produce work in cycles comprising four stages: two isothermal ionic insertion/de-insertion steps and two steps involving acid and base injection. On the basis of the mixing free energy associated with the reaction free energy, we have developed the thermodynamic formalism by considering reversible electrochemical processes to determine the maximum work performed by this acid-base machine and the efficiency. Electrochemical methods in the time and frequency domains helped in investigating the kinetics of sodium ions and proton insertion in host matrices consisting of copper hexacyanoferrate and phosphomolybdic acid, respectively, to improve our understanding of the factors underlying dissipation as a function of pH and pNa. The full cell composed of these insertion electrodes was used as a proof of concept. It performed a maximum work of 26.4 kJ per mol of electro-inserted ion from HCl solution neutralization with the addition of NaOH, to simulate acidic wastewater treatment in a profitable and sustainable way.

  13. 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. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. 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 a...

  15. Role of neutral ceramidase in colon cancer.

    Science.gov (United States)

    García-Barros, Mónica; Coant, Nicolas; Kawamori, Toshihiko; Wada, Masayuki; Snider, Ashley J; Truman, Jean-Philip; Wu, Bill X; Furuya, Hideki; Clarke, Christopher J; Bialkowska, Agnieszka B; Ghaleb, Amr; Yang, Vincent W; Obeid, Lina M; Hannun, Yusuf A

    2016-12-01

    Alterations in sphingolipid metabolism, especially ceramide and sphingosine 1-phosphate, have been linked to colon cancer, suggesting that enzymes of sphingolipid metabolism may emerge as novel regulators and targets in colon cancer. Neutral ceramidase (nCDase), a key enzyme in sphingolipid metabolism that hydrolyzes ceramide into sphingosine, is highly expressed in the intestine; however, its role in colon cancer has not been defined. Here we show that molecular and pharmacological inhibition of nCDase in colon cancer cells increases ceramide, and this is accompanied by decreased cell survival and increased apoptosis and autophagy, with minimal effects on noncancerous cells. Inhibition of nCDase resulted in loss of β-catenin and inhibition of ERK, components of pathways relevant for colon cancer development. Furthermore, inhibition of nCDase in a xenograft model delayed tumor growth and increased ceramide while decreasing proliferation. It is noteworthy that mice lacking nCDase treated with azoxymethane were protected from tumor formation. Taken together, these studies show that nCDase is pivotal for regulating initiation and development of colon cancer, and these data suggest that this enzyme is a suitable and novel target for colon cancer therapy.-García-Barros, M., Coant, N., Kawamori, T., Wada, M., Snider, A. J., Truman, J.-P., Wu, B. X., Furuya, H., Clarke, C. J., Bialkowska, A. B., Ghaleb, A., Yang, V. W., Obeid, L. M., Hannun, Y. A. Role of neutral ceramidase in colon cancer. © FASEB.

  16. Laboratory simulation of cometary neutral gas ionization

    Science.gov (United States)

    Chang, Tsuey-Fen; Rahman, H. U.; White, R. S.

    1989-01-01

    The laboratory simulation of the interaction of the solar wind with a comet is used to study the cometary neural 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.

  17. EDITORIAL: Negative ion based neutral beam injection

    Science.gov (United States)

    Hemsworth, R. S.

    2006-06-01

    It is widely recognized that neutral beam injection (NBI), i.e. the injection of high energy, high power, beams of H or D atoms, is a flexible and reliable system that has been the main heating system on a large variety of fusion devices, and NBI has been chosen as one of the three heating schemes of the International Tokomak Reactor (ITER). To date, all the NBI systems but two have been based on the neutralization (in a simple gas target) of positive hydrogen or deuterium ions accelerated to 1 MeV/nucleon. Unfortunately H- and D- are difficult to create, and the very characteristic that makes them attractive, the ease with which the electron is detached from the ion, means that it is difficult to create high concentrations or fluxes of them, and it is difficult to avoid substantial, collisional, losses in the extraction and acceleration processes. However, there has been impressive progress in negative ion sources and accelerators over the past decade, as demonstrated by the two pioneering, operational, multi-megawatt, negative ion based, NBI systems at LHD (180 keV, H0) and JT-60U (500 keV, D0), both in Japan. Nevertheless, the system proposed for ITER represents a substantial technological challenge as an increase is required in beam energy, to 1 MeV, D0, accelerated ion (D-) current, to 40 A, accelerated current density, 200 A m-2 of D-, and pulse length, to 1 h. At the Fourth IAEA Technical Meeting on Negative Ion Based Neutral Beam Injectors, hosted by the Consorzio RFX, Padova, Italy, 9-11 May 2005, the status of the R&D aimed at the realization of the injectors for ITER was presented. Because of the importance of this development to the success of the ITER project, participants at that meeting were asked if they were interested in rewriting and extending their contributions as a submission to Nuclear Fusion. Technology papers were accepted because of the very nature of the subject. The submissions underwent the regular double-referee peer-review process

  18. Rapid escape from preserved cross-reactive neutralizing humoral immunity without loss of viral fitness in HIV-1-infected progressors and long-term nonprogressors.

    Science.gov (United States)

    van Gils, Marit J; Bunnik, Evelien M; Burger, Judith A; Jacob, Yodit; Schweighardt, Becky; Wrin, Terri; Schuitemaker, Hanneke

    2010-04-01

    A substantial proportion of human immunodeficiency virus type 1 (HIV-1)-infected individuals has cross-reactive neutralizing activity in serum, with a similar prevalence in progressors and long-term nonprogressors (LTNP). We studied whether disease progression in the face of cross-reactive neutralizing serum activity is due to fading neutralizing humoral immunity over time or to viral escape. In three LTNP and three progressors, high-titer cross-reactive HIV-1-specific neutralizing activity in serum against a multiclade pseudovirus panel was preserved during the entire clinical course of infection, even after AIDS diagnosis in progressors. However, while early HIV-1 variants from all six individuals could be neutralized by autologous serum, the autologous neutralizing activity declined during chronic infection. This could be attributed to viral escape and the apparent inability of the host to elicit neutralizing antibodies to the newly emerging viral escape variants. Escape from autologous neutralizing activity was not associated with a reduction in the viral replication rate in vitro. Escape from autologous serum with cross-reactive neutralizing activity coincided with an increase in the length of the variable loops and in the number of potential N-linked glycosylation sites in the viral envelope. Positive selection pressure was observed in the variable regions in envelope, suggesting that, at least in these individuals, these regions are targeted by humoral immunity with cross-reactive potential. Our results may imply that the ability of HIV-1 to rapidly escape cross-reactive autologous neutralizing antibody responses without the loss of viral fitness is the underlying explanation for the absent effect of potent cross-reactive neutralizing humoral immunity on the clinical course of infection.

  19. Fundamentals of a Multi-Phase, Neutral-Point Clamped Multilevel ...

    African Journals Online (AJOL)

    The conventional five-level diode-clamped inverter suffers from the problem of many active power switches when extended to multiphase system. As a consequence, increasing number of gate drive circuits are required; resulting in complex system circuitry. This paper presents the fundamentals of a multiphase, neutral ...

  20. The neural representation of emotionally neutral faces and places in patients with panic disorder with agoraphobia.

    Science.gov (United States)

    Petrowski, Katja; Wintermann, Gloria; Smolka, Michael N; Huebner, Thomas; Donix, Markus

    2014-01-01

    Panic disorder with agoraphobia (PD-A) has been associated with abnormal neural activity for threat-related stimuli (faces, places). Recent findings suggest a disturbed neural processing of emotionally neutral stimuli at a more general level. Using functional magnetic resonance imaging (fMRI) we investigated the neural processing of emotionally neutral faces and places in PD-A. Fifteen patients with PD-A and fifteen healthy subjects participated in the study. When they perceived neutral faces and places, the patients with PD-A showed significantly less brain activity in the fusiform gyrus, the inferior occipital gyrus, the calcarine gyrus, the cerebellum, and the cuneus compared with the healthy controls. However, the patients with PD-A showed significantly more brain activity in the precuneus compared with controls subjects. It was not possible to distinguish the agoraphobia-associated effects from possible contributions due to general anxiety induced by fMRI. For future investigations, an additional clinical control group with patients suffering from panic disorder without agoraphobia would be of interest. In addition, the psychopathology concerning the agoraphobic symptoms needs to be investigated in more detail. The findings suggest altered neural processing of emotionally neutral faces and places in patients with PD-A. Reduced neural activity in different brain regions may indicate difficulties in recognizing the emotional content in face and place stimuli due to anxiety-related hyper-arousal. © 2013 Published by Elsevier B.V.

  1. Measurement of neutral current coherent neutral pion production on carbon in a few-GeV neutrino beam

    CERN Document Server

    Kurimoto, Y; Brice, S J; Bugel, L; Catala-Perez, J; Cheng, G; Conrad, J M; Djurcic, Z; Dore, U; Finley, D A; Franke, A J; Giganti, C; Gomez-Cadenas, J J; Guzowski, P; Hanson, A; Hayato, Y; Hiraide, K; Jover-Manas, G; Karagiorgi, G; Katori, T; Kobayashi, Y K; Kobilarcik, T; Kubo, H; Louis, W C; Loverre, P F; Ludovici, L; Mahn, K B M; Mariani, C; Masuike, S; Matsuoka, K; McGary, V T; Metcalf, W; Mills, G B; Mitsuka, G; Miyachi, Y; Mizugashira, S; Moore, C D; Nakajima, Y; Nakaya, T; Napora, R; Nienaber, P; Orme, D; Otani, M; Russell, A D; Sanchez, F; Shaevitz, M H; Shibata, T -A; Sorel, M; Stefanski, R J; Takei, H; Tanaka, H -K; Tanaka, M; Tayloe, R; Taylor, I J; Tesarek, R J; Uchida, Y; Van de Water, R; Walding, J J; Wascko, M O; White, H B; Wilking, M J; Yokoyama, M; Zeller, G P; Zimmerman, E D

    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 coherent pion to neutral current coherent pion production is calculated to be 0.14+0.30 -0.28, using our published charged current coherent pion measurement.

  2. Enhanced formulations for neutralization of chemical, biological and industrial toxants

    Science.gov (United States)

    Tucker, Mark D [Albuqueque, NM

    2008-06-24

    An enhanced formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The enhanced formulation according to the present invention is non-toxic and non-corrosive and can be delivered by a variety of means and in different phases. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator and water.

  3. Effects of neutral gas releases on electron beam injection from electrically tethered spacecraft

    Science.gov (United States)

    Winglee, R. M.

    1990-01-01

    The presence of high neutral densities at low altitudes and/or during thruster firings is known to modify the spacecraft potential during active electron beam injection. Two-dimensional (three velocity) particle simulations are used to investigate the ionization processes including the neutral density required, the modification of the spacecraft potential, beam profile and spatial distribution of the return current into the spacecraft. Three processes are identified: (1) beam-induced ionization, (2) vehicle-induced ionization, and (3) beam plasma discharge. Only in the first two cases does the beam propagate away with little distortion.

  4. Correspondence of Neutralizing Humoral Immunity and CD4 T Cell Responses in Long Recovered Sudan Virus Survivors.

    Science.gov (United States)

    Sobarzo, Ariel; Stonier, Spencer W; Herbert, Andrew S; Ochayon, David E; Kuehne, Ana I; Eskira, Yael; Fedida-Metula, Shlomit; Tali, Neta; Lewis, Eli C; Egesa, Moses; Cose, Stephen; Lutwama, Julius Julian; Yavelsky, Victoria; Dye, John M; Lobel, Leslie

    2016-05-11

    Robust humoral and cellular immunity are critical for survival in humans during an ebolavirus infection. However, the interplay between these two arms of immunity is poorly understood. To address this, we examined residual immune responses in survivors of the Sudan virus (SUDV) outbreak in Gulu, Uganda (2000-2001). Cytokine and chemokine expression levels in SUDV stimulated whole blood cultures were assessed by multiplex ELISA and flow cytometry. Antibody and corresponding neutralization titers were also determined. Flow cytometry and multiplex ELISA results demonstrated significantly higher levels of cytokine and chemokine responses in survivors with serological neutralizing activity. This correspondence was not detected in survivors with serum reactivity to SUDV but without neutralization activity. This previously undefined relationship between memory CD4 T cell responses and serological neutralizing capacity in SUDV survivors is key for understanding long lasting immunity in survivors of filovirus infections.

  5. Correspondence of Neutralizing Humoral Immunity and CD4 T Cell Responses in Long Recovered Sudan Virus Survivors

    Directory of Open Access Journals (Sweden)

    Ariel Sobarzo

    2016-05-01

    Full Text Available Robust humoral and cellular immunity are critical for survival in humans during an ebolavirus infection. However, the interplay between these two arms of immunity is poorly understood. To address this, we examined residual immune responses in survivors of the Sudan virus (SUDV outbreak in Gulu, Uganda (2000–2001. Cytokine and chemokine expression levels in SUDV stimulated whole blood cultures were assessed by multiplex ELISA and flow cytometry. Antibody and corresponding neutralization titers were also determined. Flow cytometry and multiplex ELISA results demonstrated significantly higher levels of cytokine and chemokine responses in survivors with serological neutralizing activity. This correspondence was not detected in survivors with serum reactivity to SUDV but without neutralization activity. This previously undefined relationship between memory CD4 T cell responses and serological neutralizing capacity in SUDV survivors is key for understanding long lasting immunity in survivors of filovirus infections.

  6. A Review on Venom Enzymes Neutralizing Ability of Secondary Metabolites from Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Pushpendra Singh

    2017-09-01

    Full Text Available Objectives: Medicinal plants are vital sources of bioactive compounds that are useful for the treatment of patients with snake bites or are indirectly applicable for boosting the effects of conventional serum therapy. These plants are being used traditionally by local healers and tribes for the treatment of patients with snake bites and therefore can be used as an alternative against snake envenomation. Scientifically, using the secondary metabolites of plants to neutralize venom enzymes has an extra benefit of being based on traditional knowledge; also, the use of such metabolites for the treatment of patients with snake bites is cheaper and the treatment can be started sooner. Methods: All the available information on various secondary metabolites exhibiting venom neutralizing ability were collected via electronic search (using Google books, Pubmed, SciFinder, Scirus, Google Scholar, and Web of Science and articles of peer-reviewed journals. Results: Recent interest in different plant has focused on isolating and identifying of different phytoconstituents that exhibit Phospholipase A2 activity and other venom enzyme neutralizing ability. In this support convincing evidence in experimental animal models are available. Conclusion: Secondary metabolites are naturally present, have no side effect, are stable for a long time, can be easily stored, and can neutralize a wide range of snake enzymes, such as phospholipase A2, hyaluronidase, protease, L-amino acid oxidase, 5’nucleotidase, etc. The current review presents a compilation of important plant secondary metabolites that are effective against snake venom due to enzyme neutralization.

  7. High heat flux test on the thermocouple embedded ITER neutral beam duct liner mock-up

    Energy Technology Data Exchange (ETDEWEB)

    Park, C.K., E-mail: ckpark@nfri.re.kr [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Kim, H.S., E-mail: hskim@nfri.re.kr [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Kim, G.H.; Ahn, H.J. [ITER Korea, National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of); Kim, S.K.; Lee, D.W. [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Urbani, M. [ITER Organization, Route de Vinon-sur-Verdon, CS 90 046, 13067, St. Paul Lez Durance, Cedex (France)

    2016-11-01

    Highlights: • Twenty thermocouples have been installed on the NB duct liner full scale mock-up. • High heat flux test has been performed. • Four thermocouple fixation schemes had been verified by high heat flux test. • Temperature behavior of the NB duct liner has been successfully simulated. - Abstract: The ITER neutral beam duct liner is located within the tokamak VV port extension and is mounted on the VV port extension flange. The duct liner is made from CuCrZr copper alloy and is actively cooled through deep-drilled channels. A number of thermocouples should be installed on the neutral beam duct liner in order to provide the ability to detect temperature excursions on the surface of the duct liner. Twenty thermocouples have been installed on the neutral beam duct liner full scale mock-up, and a high heat flux test has been performed at the KoHLT-EB test facility, in order to simulate temperature detection in the neutral beam duct liner during ITER operation. For each thermocouple, the fixation method has been verified by high heat flux test with uniform electron beam profile, and the temperature behavior of the neutral beam duct liner has been successfully simulated by Gaussian electron beam profile.

  8. Neutralizing human antibodies prevent Zika virus replication and fetal disease in mice.

    Science.gov (United States)

    Sapparapu, Gopal; Fernandez, Estefania; Kose, Nurgun; Bin Cao; Fox, Julie M; Bombardi, Robin G; Zhao, Haiyan; Nelson, Christopher A; Bryan, Aubrey L; Barnes, Trevor; Davidson, Edgar; Mysorekar, Indira U; Fremont, Daved H; Doranz, Benjamin J; Diamond, Michael S; Crowe, James E

    2016-12-15

    Zika virus (ZIKV) is an emerging mosquito-transmitted flavivirus that can cause severe disease, including congenital birth defects during pregnancy. To develop candidate therapeutic agents against ZIKV, we isolated a panel of human monoclonal antibodies from subjects that were previously infected with ZIKV. We show that a subset of antibodies recognize diverse epitopes on the envelope (E) protein and exhibit potent neutralizing activity. One of the most inhibitory antibodies, ZIKV-117, broadly neutralized infection of ZIKV strains corresponding to African and Asian-American lineages. Epitope mapping studies revealed that ZIKV-117 recognized a unique quaternary epitope on the E protein dimer-dimer interface. We evaluated the therapeutic efficacy of ZIKV-117 in pregnant and non-pregnant mice. Monoclonal antibody treatment markedly reduced tissue pathology, placental and fetal infection, and mortality in mice. Thus, neutralizing human antibodies can protect against maternal-fetal transmission, infection and disease, and reveal important determinants for structure-based rational vaccine design efforts.

  9. Vacuum lubricants based on neutral oil

    Energy Technology Data Exchange (ETDEWEB)

    Artem' yeva, V.P.; Potanina, V.A.; Kucheryavaya, N.N.; Orlova, S.N.; Gorbacheva, S.G.

    1983-01-01

    Basic parameters for high-vacuum pumps such as minimal residual vapor pressure, rapid operation and vacuum collapse resistance depend on type and properties of hydraulic fluids, which include mineral oils, esters of organic alcohols and acids and organic silicon compounds. Mineral oils have been used most because of their thermal stability and low cost. This article reports studies of such oils based on domestic naphthene-paraffin hydrocarbons and medical vaseline processed from Balakhan petroleum. Neutral naphthene oil with 90% saturated hydrocarbons was found suitable for vacuum oils after purification and distillation. Its origin as a by-product of sulfonate additive production, and resultant low cost, recommend this oil for full production.

  10. Neutral gas transport modeling with DEGAS 2

    Energy Technology Data Exchange (ETDEWEB)

    Stotler, D.; Karney, C.

    1993-10-01

    We are currently rewriting the neutral gas transport code, DEGAS with a view to not only making it faster, but also easing the process of including new physics. The goal is to make adding new species and reactions relatively simple so that the code can be rapidly adapted to new divertor physics regimes. DEGAS 2 will also be optimized for coupling to fluid plasma codes, incorporating many of the techniques utilized in B2-EIRENE. Finally, it is our intention that DEGAS 2, like DEGAS, be well-documented and easy to use. We ill present model calculations including ionization and charge exchange which will illustrate the way reactions are included into DEGAS 2 and will demonstrate operation of the code on a distributed network of workstations.

  11. Quantum computing implementations with neutral particles

    DEFF Research Database (Denmark)

    Negretti, Antonio; Treutlein, Philipp; Calarco, Tommaso

    2011-01-01

    We review quantum information processing with cold neutral particles, that is, atoms or polar molecules. First, we analyze the best suited degrees of freedom of these particles for storing quantum information, and then we discuss both single- and two-qubit gate implementations. We focus our...... discussion mainly on collisional quantum gates, which are best suited for atom-chip-like devices, as well as on gate proposals conceived for optical lattices. Additionally, we analyze schemes both for cold atoms confined in optical cavities and hybrid approaches to entanglement generation, and we show how...... optimal control theory might be a powerful tool to enhance the speed up of the gate operations as well as to achieve high fidelities required for fault tolerant quantum computation....

  12. Inflazione e prezzi relativi (Neutrality of inflation

    Directory of Open Access Journals (Sweden)

    F. PADOA-SCHIOPPA

    2014-03-01

    Full Text Available In the traditional Walrasian version of an economy with multi-sectoral exchange, the changes in relative prices and the general level of prices do not influence each other so that inflation is neutral. Various empirical studies in recent times, however, have invalidated this thesis. Unfortunately, they have not provided a well-defined alternative theoretical model, able to explain the formation of prices and rates of inflation in a context of multi-sectoral equilibrium (or disequilibrium. Therefore, some modern versions of neoclassical theory that seem to provide a multi-sectoral analytical foundation to the observed correlation between the dynamics of relative prices and the general level of prices are particularly worthy of interest. Their detailed examination, considered appropriate for both the novelty and complexity of the arguments, and their empirical data on the last two decades in Italy are the subject of the present work. JEL: E31

  13. CO adsorption on neutral iridium clusters

    CERN Document Server

    Kerpal, Christian; Meijer, Gerard; Fielicke, André

    2010-01-01

    The adsorption of carbon monoxide on neutral iridium clusters in the size range of n = 3 to 21 atoms is investigated with infrared multiple photon dissociation spectroscopy. For each cluster size only a single v(CO) band is present with frequencies in the range between 1962 cm-1 (n = 8) and 1985 cm-1 (n = 18) which can be attributed to an atop binding geometry. This behaviour is compared to the CO binding geometries on clusters of other group 9 and 10 transition metals as well as to that on extended surfaces. The preference of Ir for atop binding is rationalized by relativistic effects on the electronic structure of the later 5d metals.

  14. Age-abundance relationships for neutral communities

    Science.gov (United States)

    Danino, Matan; Shnerb, Nadav M.

    2015-10-01

    Neutral models for the dynamics of a system of competing species are often used to describe a wide variety of empirical communities. These models are used in many situations, ranging from population genetics and ecological biodiversity to macroevolution and cancer tumors. One of the main issues discussed within this framework is the relationships between the abundance of a species and its age. Here we provide a comprehensive analysis of the age-abundance relationships for fixed-size and growing communities. Explicit formulas for the average and the most likely age of a species with abundance n are given, together with the full probability distribution function. We further discuss the universality of these results and their applicability to the tropical forest community.

  15. Paradoxical suppression of poly-specific broadly neutralizing antibodies in the presence of strain-specific neutralizing antibodies following HIV infection.

    Science.gov (United States)

    Ciupe, Stanca M; De Leenheer, Patrick; Kepler, Thomas B

    2011-05-21

    One of the first immunologic responses against HIV infection is the presence of neutralizing antibodies that seem able to inactivate several HIV strains. Moreover, in vitro studies have shown the existence of monoclonal antibodies that exhibit broad crossclade neutralizing potential. Yet their number is low and slow to develop in vivo. In this paper, we investigate the potential benefits of inducing poly-specific neutralizing antibodies in vivo throughout immunization. We develop a mathematical model that considers the activation of families of B lymphocytes producing poly-specific and strain-specific antibodies and use it to demonstrate that, even if such families are successful in producing neutralizing antibodies, the competition between them may limit the poly-specific response allowing the virus to escape. We modify this model to account for viral evolution under the pressure of antibody responses in natural HIV infection. The model can reproduce viral escape under certain conditions of B lymphocyte competition. Using these models we provide explanations for the observed antibody failure in controlling natural infection and predict quantitative measures that need to be satisfied for long-term control of HIV infection. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Human Immune Response to Botulinum Pentavalent (ABCDE) Toxoid, Determined by a Neutralization Test and by an ELISA

    Science.gov (United States)

    1988-05-04

    difficult to ascertain from such assays. A good correlation between neutralizing activity and ELISA titer has been demonstrated for antibody to tetanus toxoid...15). Eighty serum samples, ranging from < 0.01 to >100 IU/ml, were assayed by both techniques. The ELISA used plates coated with tetanus toxoid... horses (3). The ELISA overcomes many of the disadvantages of the neutralization test: it does not require experimental animals, the test can be

  17. Electroacoustic isoelectric point determinations of bauxite refinery residues: different neutralization techniques and minor mineral effects.

    Science.gov (United States)

    Freire, Tiago S S; Clark, Malcolm W; Comarmond, M Josick; Payne, Timothy E; Reichelt-Brushett, Amanda J; Thorogood, Gordon J

    2012-08-14

    Bauxite refinery residue (BRR) is a highly caustic, iron hydroxide-rich byproduct from alumina production. Some chemical treatments of BRR reduce soluble alkalinity and lower residue pH (to values <10) and generate a modified BRR (MBRR). MBRR has excellent acid neutralizing (ANC) and trace-metal adsorption capacities, making it particularly useful in environmental remediation. However, soluble ANC makes standard acid-base isoelectric point (IEP) determination difficult. Consequently, the IEP of a BRR and five MBRR derivatives (sulfuric acid-, carbon dioxide-, seawater-, a hybrid neutralization, i.e, partial CO(2) neutralization followed by seawater, and an activated-seawater-neutralized MBRR) were determined using electroacoustic techniques. Residues showed three significantly different groups of IEPs (p < 0.05) based around the neutralization used. Where the primary mineral assemblage is effectively unchanged, the IEPs were not significantly different from BRR (pH 6.6-6.9). However, neutralizations generating neoformational minerals (alkalinity precipitation) significantly increased the IEP to pH 8.1, whereas activation (a removal of some primary mineralogy) significantly lowered the IEP to pH 6.2. Moreover, surface charging curves show that surfaces remain in the ±30 mV surface charge instability range, which provides an explanation as to why MBRRs remove trace metals and oxyanions over a broad pH range, often simultaneously. Importantly, this work shows that minor mineral components in complex mineral systems may have a disproportionate effect on the observable bulk IEP. Furthermore, this work shows the appropriateness of electroacoustic techniques in investigating samples with significant soluble mineral components (e.g., ANC).

  18. Neutral pion production measurements at SciBooNE

    Energy Technology Data Exchange (ETDEWEB)

    Catala-Perez, J. [IFIC, CSIC/U. Valencia (Spain)

    2011-08-15

    Neutrino-induced neutral pion production is an important measurement for next generation neutrino oscillation experiments. Neutral current (NC) neutral pion production is a direct background for electron neutrino appearance experiments, while charged current (CC) neutral pion production affects experiments looking for muon neutrino disappearance. Located in the Booster Neutrino Beam at Fermilab, SciBooNE is a neutrino scattering experiment designed to accurately measure muon neutrino and anti-neutrino cross sections on carbon near 1 GeV neutrino energy. In this talk I will present recent SciBooNE results on neutral pion production, including the total cross section measurement for both channels relative to the CC inclusive cross section, the separation of the coherent and incoherent contributions to the NC channel, and details on neutral pion production kinematics.

  19. Alkalinity conversion of bauxite refinery residues by neutralization.

    Science.gov (United States)

    Johnston, M; Clark, M W; McMahon, P; Ward, N

    2010-10-15

    Red mud remains the largest environmental issue for the alumina industry due to its high pH (>13), fine-grained nature (>90% is 50 g/kg), and soluble alkalinity (approximately 30 g/kg as equivalent CaCO(3)), which reduce the transport and reuse options of red mud. The neutralization of red mud provides potential reuse options because neutralization lowers pH, increases grain-size (e.g., coagulation), and precipitates or converts alkalinity. This paper investigates the geochemistry of 3 treatments of a red mud to affect neutralization and potentially convert materials from a waste material to a resource. This study investigates two commonly used neutralization techniques, a CO(2)-neutralized red mud (CNRM), a Basecon-neutralized red mud (Basecon), and a more novel approach of a CO(2)-neutralization followed by a Basecon-neutralization (Hybrid) to understand the effects that these treatments have on neutralization process. Data indicate that the neutralization techniques form two distinct geochemical groups when discriminated on total alkalinity alone, that is treatments with, and treatments without alkalinity precipitation. However, each treatment has distinct alkalinity speciation (hydroxide-dominant or carbonate/bicarbonate dominant) and residual Ca, Mg and Al in the treatment solution. Similarly, solids produced differ in their reaction pH and ANC, and contrary pH and ANC, a contrary to other studies, Dawsonite was not seen to precipitate during any neutralization. However, despite this approximately 17 g/kg CO(2) was sequestered during CNRM and hybrid neutralizations and all treatments increased either the transport or reuse options of red mud in some way. 2010 Elsevier B.V. All rights reserved.

  20. Coherent and neutral pion production results from MINERνA

    Energy Technology Data Exchange (ETDEWEB)

    Palomino, J. L. [Centro Brasileiro de Pesquisas Físicas, Rua Dr. Xavier Sigaud 150, Urca, Rio de Janeiro, 22290-180 (Brazil); Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Higuera, A. [Universidad de Guanajuato, Lascuraín de Retana No. 5, Col. Centro. Guanajuato 36000, Guanajuato. México (Mexico)

    2015-05-15

    MINERνA is a neutrino-nucleus scattering experiment employing multiple nuclear targets. The experiment is studying neutral pion production due to coherent, resonant and deep-inelastic processes, from both charged current and neutral current reactions. Neutral pions are detected through their two photon decay and the resultant electromagnetic showers. We will describe the analysis for the cross sections of inclusive and exclusive processes.

  1. Towards a Revised Monte Carlo Neutral Particle Surface Interaction Model

    Energy Technology Data Exchange (ETDEWEB)

    D.P. Stotler

    2005-06-09

    The components of the neutral- and plasma-surface interaction model used in the Monte Carlo neutral transport code DEGAS 2 are reviewed. The idealized surfaces and processes handled by that model are inadequate for accurately simulating neutral transport behavior in present day and future fusion devices. We identify some of the physical processes missing from the model, such as mixed materials and implanted hydrogen, and make some suggestions for improving the model.

  2. Rocket-borne Lithium ejection system for neutral wind measurement

    Science.gov (United States)

    Habu, H.; Yamamoto, M.; Watanabe, S.; Larsen, M. F.

    2013-11-01

    Chemical tracer releases represent the most widely used technique for in situ neutral wind measurements in the thermosphere/ionosphere region. Different chemicals have been used for this purpose, but lithium releases in particular provide some unique capabilities due to the strong resonant emissions that are produced when lithium is illuminated by sunlight. The majority of the lithium releases from sounding rockets were carried out in the 1960's and 1970's, but there has been recent renewed interest in the use of lithium vapor releases to extend neutral wind measurements into the F region and for daytime wind profile measurements in the E region. The rocketborne Lithium Ejection System (LES) is a chemical release device that has been developed for the Japanese space research program. Since lithium vapor acts as a neutral tracer, the winds are obtained by tracking the motion of the clouds or trails optically from the ground using the bright red emission that is characteristic of the chemical. Lithium is a solid at room temperature, so that a gas release requires rapid vaporization of the metal to make the cloud at the intended altitude. The release canister is designed to produce a high-heat chemical reaction without gaseous products. Appropriate mixtures of thermite are employed as the heat source. In early experiments, lithium pellets were mixed directly into the thermite. However, since lithium is an active chemical, the use of lithium-thermite mixtures creates potential hazards when used in a rocket-borne device. Moreover, the pyrotechnic devices used to ignite the thermite also have to be considered in the payload canister design to assure that the safety standards for sounding rockets are satisfied. The design of the LES, described in this paper, was based on the safety requirements and the reliability in storing and handling of the materials. The LES design is also flexible in that the lithium tracer material can be replaced with other chemicals without

  3. Neutral and Non-Neutral Evolution of Duplicated Genes with Gene Conversion

    Directory of Open Access Journals (Sweden)

    Jeffrey A. Fawcett

    2011-02-01

    Full Text Available Gene conversion is one of the major mutational mechanisms involved in the DNA sequence evolution of duplicated genes. It contributes to create unique patters of DNA polymorphism within species and divergence between species. A typical pattern is so-called concerted evolution, in which the divergence between duplicates is maintained low for a long time because of frequent exchanges of DNA fragments. In addition, gene conversion affects the DNA evolution of duplicates in various ways especially when selection operates. Here, we review theoretical models to understand the evolution of duplicates in both neutral and non-neutral cases. We also explain how these theories contribute to interpreting real polymorphism and divergence data by using some intriguing examples.

  4. Compositional design and optimization of dentin adhesive with neutralization capability

    National Research Council Canada - National Science Library

    Song, Linyong; Ye, Qiang; Ge, Xueping; Spencer, Paulette

    2015-01-01

    The objective of this work was to investigate the polymerization behavior, neutralization capability, and mechanical properties of dentin adhesive formulations with the addition of the tertiary amine...

  5. ON THE SUPPORT OF NEUTRALS AGAINST GRAVITY IN SOLAR PROMINENCES

    Energy Technology Data Exchange (ETDEWEB)

    Terradas, J.; Soler, R.; Oliver, R.; Ballester, J. L., E-mail: jaume.terradas@uib.es [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain)

    2015-04-01

    Cool and dense prominences found in the solar atmosphere are known to be partially ionized because of their relatively low temperature. In this Letter, we address the long-standing problem of how the neutral component of the plasma in prominences is supported against gravity. Using the multiple-fluid approach, we solve the time-dependent equations in two dimensions considering the frictional coupling between the neutral and ionized components of the magnetized plasma representative of a solar prominence embedded in a hot coronal environment. We demonstrate that given an initial density enhancement in the two fluids, representing the body of the prominence, the system is able to relax in the vicinity of magnetic dips to a stationary state in which both neutrals and ionized species are dynamically suspended above the photosphere. Two different coupling processes are considered in this study: collisions between ions and neutrals and charge exchange interactions. We find that for realistic conditions, ions are essentially static, while neutrals have a very small downflow velocity. The coupling between ions and neutrals is so strong at the prominence body that the behavior is similar to that of a single fluid with an effective density equal to the sum of the ion and neutral species. We also find that the charge exchange mechanism is about three times more efficient at sustaining neutrals than elastic scattering of ions with neutrals.

  6. Edge momentum transport by neutrals: an interpretive numerical framework

    Science.gov (United States)

    Omotani, J. T.; Newton, S. L.; Pusztai, I.; Viezzer, E.; Fülöp, T.; The ASDEX Upgrade Team

    2017-06-01

    Due to their high cross-field mobility, neutrals can contribute to momentum transport even at the low relative densities found inside the separatrix and they can generate intrinsic rotation. We use a charge-exchange dominated solution to the neutral kinetic equation, coupled to neoclassical ions, to evaluate the momentum transport due to neutrals. Numerical solutions to the drift-kinetic equation allow us to cover the full range of collisionality, including the intermediate levels typical of the tokamak edge. In the edge there are several processes likely to contribute to momentum transport in addition to neutrals. Therefore, we present here an interpretive framework that can evaluate the momentum transport through neutrals based on radial plasma profiles. We demonstrate its application by analysing the neutral angular momentum flux for an L-mode discharge in the ASDEX Upgrade tokamak. The magnitudes of the angular momentum fluxes we find here due to neutrals of 0.6-2 \\text{N} \\text{m} are comparable to the net torque on the plasma from neutral beam injection, indicating the importance of neutrals for rotation in the edge.

  7. Neutralization of Naja naja venom induced lethality, edema and myonecrosis by ethanolic root extract of Coix lacryma-jobi.

    Science.gov (United States)

    Rajesh, K S; Bharath, B R; Rao, C V; Bhat, K I; Bhat, K S Chandrashekhar; Bhat, Pritesh

    2017-01-01

    Coix lacryma-jobi, commonly known as job's tear, is a tall grain-bearing tropical plant of the family Poaceae. The ethanolic root extract (ERE) of the plant was investigated for the first time for anti-venom activity against Indian cobra Naja naja venom. In-vitro studies were conducted to determine neutralization of phospholipase A2 (PLA2) activity of the Naja naja venom by the ERE. ERE showed significant inhibition of PLA2 activity, which was further confirmed from effective neutralization of human red blood cells (HRBC) lysis induced by the venom. In addition, venom-induced proteolysis, fibrinogenolysis, DNase activity were also neutralized by the ERE, which contained carbohydrates, glycolides, resins and tannins. Oral administration of ERE at doses levels 100, 200 and 400 mg/kg effectively inhibited Naja naja venom-induced lethality in mice. Myotoxicity induced by Naja naja venom, measured by creatine kinase activity in rats was significantly neutralized by the ERE at a dose of 200 mg/kg. Stigmasterol, as one of the component isolated from the ERE, was found to have venom phospholipase A2 inhibition potential, which was confirmed by molecular docking studies with PLA2. In summary, these studies indicate the ability of ERE of Coix lacryma-jobi to effectively neutralize the toxic effects of the venom is, in part, contributed by the inhibition of PLA2 activity among other venom-derived factors.

  8. Limited Neutralizing Antibody Specificities Drive Neutralization Escape in Early HIV-1 Subtype C Infection

    OpenAIRE

    Rong Rong; Bing Li; Lynch, Rebecca M.; Haaland, Richard E.; Murphy, Megan K.; Joseph Mulenga; Allen, Susan A.; Abraham Pinter; Shaw, George M.; Eric Hunter; Robinson, James E.; Gnanakaran, S.; Derdeyn, Cynthia A.

    2009-01-01

    One aim for an HIV vaccine is to elicit neutralizing antibodies (Nab) that can limit replication of genetically diverse viruses and prevent establishment of a new infection. Thus, identifying the strengths and weaknesses of Nab during the early stages of natural infection could prove useful in achieving this goal. Here we demonstrate that viral escape readily occurred despite the development of high titer autologous Nab in two subjects with acute/early subtype C infection. To provide a detail...

  9. Rabbit IgG antibodies against Phospholipase A2 from Crotalus durissus terrificus neutralize the lethal activity of the venom Los anticuerpos IgG de conejos anti-fosfolipasa A2 de Crotalus durissus terrificus neutralizan la actividad letal del veneno

    Directory of Open Access Journals (Sweden)

    Juan P. Rodríguez

    2006-12-01

    Full Text Available Crotalus durissus terrificus (C.d.t. (South American rattlesnake venom possesses myotoxic and neurotoxic activities, both of which are also expressed by crotoxin, the principal toxin of this venom. Crotoxin contains a basic phospholipase A2 (PLA2 and a non toxic acidic protein, crotapotin. We have produced and investigated the ability of IgG antibodies raised in rabbits against PLA2 to neutralize the lethality of the whole venom. PLA2 was isolated by gel filtration chromatography (Sephadex G-75. Specific antibodies were obtained by subcutaneous and intramuscular inoculation of PLA2 (700 µg with Freund adjuvant. Groups of six mice (20 + 2 g were inoculated with 0.5 ml i.p. of C. d. t. venom (4 µg or a mixture of venom that had been preincubated with the desired volume of IgG antibodies. Mortality, recorded 24 and 48 h after inoculation, showed that IgG anti-PLA2 were more effective than anticrotalic serum in neutralizing the lethal activity. These results demonstrate that it could be possible to obtain an anti-venom made by specific antibodies with a high level of protection against the lethal component of C.d.t. venom, and/or the inclusion of these antibodies as a supplement in heterologous anti-venoms.El veneno de Crotalus durissus terrificus (C.d.t. (Cascabel de Sud América posee actividad miotóxica y neurotóxica, actividades que también exhibe el complejo crotoxina, principal componente tóxico de este veneno. El complejo crotoxina está constituido por una fosfolipasa A2 básica (PLA2 y una proteína acídica no tóxica, el crotapotín. En este trabajo se estudió la capacidad neutralizante de anticuerpos IgG anti-PLA2 sobre la letalidad inducida por el veneno entero. El antígeno PLA2, fue aislado por cromatografía de filtración en gel (Sephadex G-75. Se inocularon conejos machos por vía subcutánea e intramuscular, con 700 µg de PLA2 y adyuvante para la obtención de anticuerpos específicos. La capacidad neutralizante del

  10. Applying neutral drift to the directed molecular evolution of a β-glucuronidase into a β-galactosidase: Two different evolutionary pathways lead to the same variant

    Directory of Open Access Journals (Sweden)

    Hale Jennifer R

    2011-05-01

    Full Text Available Abstract Background Directed protein evolution has been used to modify protein activity and research has been carried out to enhance the production of high quality mutant libraries. Many theoretical approaches suggest that allowing a population to undergo neutral selection may be valuable in directed evolution experiments. Findings Here we report on an investigation into the value of neutral selection in a classical model system for directed evolution, the conversion of the E. coli β-glucuronidase to a β-galactosidase activity. We find that neutral selection, i.e. selection for retaining glucuronidase activity, can efficiently identify the majority of sites of mutation that have been identified as beneficial for galactosidase activity in previous experiments. Each variant demonstrating increased galactosidase activity identified by our neutral drift experiments contained a mutation at one of four sites, T509, S557, N566 or W529. All of these sites have previously been identified using direct selection for beta galactosidase activity. Conclusions Our results are consistent with others that show that a neutral selection approach can be effective in selecting improved variants. However, we interpret our results to show that neutral selection is, in this case, not a more efficient approach than conventional directed evolution approaches. However, the neutral approach is likely to be beneficial when the resulting library can be screened for a range of related activities. More detailed statistical studies to resolve the apparent differences between this system and others are likely to be a fruitful avenue for future research.

  11. A Comprehensive Review of the Pharmacodynamics, Pharmacokinetics, and Clinical Effects of the Neutral Endopeptidase Inhibitor Racecadotril

    OpenAIRE

    Marion eEberlin; Thomas eMück; Michel, Martin C.

    2012-01-01

    Racecadotril, via its active metabolite thiorphan, is an inhibitor of the enzyme neutral endopeptidase (NEP, EC 3.4.24.11), thereby increasing exposure to NEP including enkephalins and atrial natriuretic peptide. Upon oral administration racecadotril is rapidly and effectively converted into the active metabolite thiorphan, which does not cross the blood-brain-barrier. Racecadotril has mainly been tested in animal models and patients of three therapeutic areas. As an analgesic the effects of ...

  12. Neutralizing antibodies hamper IFNbeta bioactivity and treatment effect on MRI in patients with MS

    DEFF Research Database (Denmark)

    Sørensen, Per Soelberg; Tscherning, MD; Kahr Mathiesen, Henrik

    2006-01-01

    We measured neutralizing antibodies (NABs) and the in vivo biologic response to interferon-beta on neopterin and beta(2)-microglobulin blood levels. All NAB-negative patients had an in vivo biologic response (full or partial), whereas all high-level positive patients had no response. High-level N...... patients had more MRI activity than NAB-negative patients (p = 0.031). Patients with a full response had less MRI activity than patients without biologic response (p = 0.032)....

  13. A measurement of coherent neutral pion production in neutrino neutral current interactions in the NOMAD experiment

    Science.gov (United States)

    Kullenberg, C. T.; Mishra, S. R.; Seaton, M. B.; Kim, J. J.; Tian, X. C.; Scott, A. M.; Kirsanov, M.; Petti, R.; Alekhin, S.; Astier, P.; Autiero, D.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P. W.; Cavasinni, V.; Cervera-Villanueva, A.; Challis, R.; Chukanov, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Degaudenzi, H.; De Santo, A.; Del Prete, T.; Di Lella, L.; do Couto e Silva, E.; Dumarchez, J.; Ellis, M.; Feldman, G. J.; Ferrari, R.; Ferrère, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.-M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Gninenko, S.; Godley, A.; Gomez-Cadenas, J.-J.; Gosset, J.; Gößling, C.; Gouanère, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kent, N.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Ku