630 research outputs found
The experimental study of the Bi-Sn, Bi-Zn and Bi-Sn-Zn systems
The binary BiSn was studied by means of SEM (Scanning Electron Microscopy)/EDS (Energy-Dispersive solid state Spectrometry), DTA
(Differential Thermal Analysis)/DSC (Differential Scanning Calorimetry) and RT-XRD (Room Temperature X-Ray Diffraction) in order to clarify
discrepancies concerning the Bi reported solubility in (Sn). It was found that (Sn) dissolves approximately 10 wt% of Bi at the eutectic temperature.
The experimental effort for the BiZn system was limited to the investigation of the discrepancies concerning the solubility limit of Zn in (Bi)
and the solubility of Bi in (Zn). Results indicate that the solubility of both elements in the respective solid solution is approximately 0.3 wt% at
200 C.
Three different features were studied within the BiSnZn system. Although there are enough data to establish the liquid miscibility gap
occurring in the phase diagram of binary BiZn, no data could be found for the ternary. Samples belonging to the isopleths with w(Bi) 10%
and w(Sn) 5%, 13% and 19% were measured by DTA/DSC. The aim was to characterize the miscibility gap in the liquid phase. Samples
belonging to the isopleths with w(Sn) 40%, 58%, 77/81% and w(Zn) 12% were also measured by DTA/DSC to complement the study of
BiSnZn. Solubilities in the solid terminal solutions were determined by SEM/EDS. Samples were also analyzed by RT-XRD and HT-XRD
(High Temperature X-Ray Diffraction) confirming the DTA/DSC results for solid state phase equilibria
Carbohydrate carbon sources induce loss of flocculation of an ale-brewing yeast strain
Aims: To identify the nutrients that can trigger the loss of flocculation under growth conditions in an ale-brewing strain, Saccharomyces cerevisiae NCYC 1195.
Methods and Results: Flocculation was evaluated using the method of Soares, EX. and Vroman, A. [Journal of Applied Microbiology (2003) 95, 325]. Yeast growth with metabolizable carbon sources (glucose, fructose, galactose, maltose or sucrose) at 2% (w/v), induced the loss of flocculation in yeast that had previously been allowed to flocculate. The yeast remained flocculent when transferred to a medium containing the required nutrients for yeast growth and a sole nonmetabolizable carbon source (lactose). Transfer of flocculent yeast into a growth medium with ethanol (4% v/v), as the sole carbon source did not induce the loss of flocculation. Even the addition of glucose (2% w/v) or glucose and antimycin A (0.1 mg lˉ¹) to this culture did not bring about loss of flocculation. Cycloheximide addition (15 mglˉ¹) to glucose-growing cells stopped flocculation loss.
Conclusions: Carbohydrates were the nutrients responsible for stimulating the loss of flocculation in flocculent yeast cells transferred to growing conditions. The glucose-induced loss of flocculation required de novo protein synthesis. Ethanol prevented glucose-induced loss of flocculation. This protective effect of ethanol was independent of the respiratory function of the yeast.
Significance and Impact of the Study: This work contributes to the elucidation of the role of nutrients in the control of the flocculation cycle in NewFlo phenotype yeast strains.Instituto Politécnico do Porto (IPP) - Fundo de Apoio à Investigação - Project P24/96 , P24/97.Programa Plurianual de Unidades de I&D-CIEA/
ISEP
Purification And N-terminal Sequencing Of Two Presynaptic Neurotoxic Pla2, Neuwieditoxin-i And Neuwieditoxin-ii, From Bothrops Neuwiedi Pauloensis (jararaca Pintada) Venom
Two presynaptic phospholipases A2 (PLA2), neuwieditoxin-I (NeuTX-I) and neuwieditoxin-II (NeuTX-II), were isolated from the venom of Bothrops neuwiedi pauloensis (BNP). The venom was fractionated using molecular exclusion HPLC (Protein-Pak 300SW column), followed by reverse phase HPLC (μBondapak C18 column). Tricine-SDS-PAGE in the presence or absence of dithiothreitol showed that NeuTX-I and NeuTX-II had a molecular mass of approximately 14 kDa and 28kDa, respectively. At 10μg/ml, both toxins produced complete neuromuscular blockade in indirectly stimulated chick biventer cervicis isolated preparation without inhibiting the response to acetylcholine, but NeuTX-II reduced the response to KCl by 67.0±8.0% (n=3; p<0.05). NeuTX-I and NeuTX-II are probably responsible for the presynaptic neurotoxicity of BNP venom in vitro. In fact, using loose patch clamp technique for mouse phrenic nerve-diaphragm preparation, NeuTX-I produced a calcium-dependent blockade of acetylcholine release and caused appearance of giant miniature end-plate potentials (mepps), indicating a pure presynaptic action. The N-terminal sequence of NeuTX-I was DLVQFGQMILKVAGRSLPKSYGAYGCYCGWGGRGK (71% homology with bothropstoxin-II and 54% homology with caudoxin) and that of NeuTX-II was SLFEFAKMILEETKRLPFPYYGAYGCYCGWGGQGQPKDAT (92% homology with Basp-III and 62% homology with crotoxin PLA2). The fact that NeuTX-I has Q-4 (Gln-4) and both toxins have F-5 (Phe-5) and Y-28 (Tyr-28) strongly suggests that NeuTX-I and NeuTX-II are Asp49 PLA2.131103121AIRD, S.D., KAISER II, LEWIS RV., KRUGGEL WG. A complete amino acid sequence for the basic subunit of crotoxin (1986) Arch. Biochem. Biophys, 249, pp. 296-300AIRD, S.D., KRUGGEL, W.G., KAISER II, Amino acid sequence of the basic subunit of Mojave toxin from the venom of the Mojave rattlesnake (Crotalus s. scutulatus) (1990) Toxicon, 28, pp. 669-673BEGHINI, D.G., TOYAMA, M.H., HYSLOP, S., SODEK, L., NOVELLO, J.C., MARANGONI, S., Enzymatic characterization of a novel phospholipase A2 from Crotalus durissus cascavella rattlesnake (maracambóia) venom (2000) J. Protein Chem, 19, pp. 603-607BORJA-OLIVEIRA, C.R., DURIGON, A.M., VALLIN, A.C.C., TOYAMA, M.H., SOUCCAR, C., MARANGONI, S., RODRIGUES-SIMIONI, L., The pharmacological effects of Bothrops neuwiedi pauloensis (jararaca-pintada) snake venom on avian neuromuscular transmission (2003) Braz. J. Med. Biol. Res, 36, pp. 617-624BORJA-OLIVEIRA, C.R., SOARES, A.M., ZAMUNER, S.R., HYSLOP, S., GIGLIO, J.R., PRADO-FRANCESCHI, J., RODRIGUES-SIMIONI, L., Intraspecific variation in the neurotoxic and myotoxic activities of Bothrops neuwiedi snake venoms (2002) J. Venom. Anim. Toxins, 8, pp. 88-101BUCARETCHI, F., HERRERA, S.R.F., HYSLOP, S., BARACAT, E.C.E., VIEIRA, R.J., Snakebites by Bothrops spp in children in Campinas, São Paulo, Brazil (2001) Rev. Inst. Med. Trop. São Paulo, 43, pp. 329-333CHO, W., KEZDY, F.J., Chromogenic substrate and assay of phospholipase A 2 (1991) Meth. Enzymol, 197, pp. 75-79CINTRA, A.C., MARANGONI, S., OLIVEIRA, B., GIGLIO, J.R., Bothropstoxin-I: Amino acid sequence and function (1993) J. Protein Chem, 12, pp. 57-64COGO, J.C., PRADO-FRANCESCHI, J., CRUZ-HÖFLING, M.A., CORRADO, A.P., RODRIGUES-SIMIONI, L., Effects of Bothrops insularis on the mouse and chick nerve-muscle preparation (1993) Toxicon, 31, pp. 1237-1247COGO, J.C., PRADO-FRANCESCHI, J., GIGLIO, J.R., CORRADO, A.P., CRUZ-HÖFLING, M.A., DONATO, J.L., LEITE, G.B., RODRIGUES-SIMIONI, L., An unusual presynaptic action of Bothrops insularis snake venom mediated by phospholipase A2 fraction (1998) Toxicon, 36, pp. 1323-1332DE SOUSA, M.V., MORHY, L., ARNI, R.K., WARD, R.J., GUTIÉRREZ, J.M., Amino acid sequence of a myotoxic Lys-49-phospholipase A2 homologue from the venom of Cerrophidion (Bothrops) godmani (1998) Biochim. Biophys. Acta, 1384, pp. 204-208DURIGON, A.M., BORJA-OLIVEIRA, C.R., DAL, B.C., OSHIMA-FRANCO, Y., COGO, J.C., LAPA, A.J., SOUCCAR, C., RODRIGUES-SIMIONI, L., Neuromuscular activity of Bothrops neuwiedi pauloensis snake venom in mouse nerve-muscle preparations (2005) J. Venom. Anim. Toxins incl. Trop. Dis, 11, pp. 22-33FONTES, M.R., SOARES, A.M., RODRIGUES, V.M., FERNANDES, A.C., DA SILVA, R.J., GIGLIO, J.R., Crystallization and preliminary X-ray diffraction analysis of a myotoxic phospholipase A(2) homologue from Bothrops neuwiedi pauloensis venom (1999) Biochim. Biophys. Acta, 1432, pp. 393-395FRANCIS, B., GUTIERREZ, J.M., LOMONTE, B., KAISER II, Myotoxin II from Bothrops asper (Terciopelo) venom is a lysine-49 phospholipase A 2 (1991) Arch. Biochem. Biophys, 284, pp. 352-359GEOGHEGAN, P., ANGULO, Y., CANGELOSI, A., DIAZ, M., LOMONTE, B., Characterization of a basic phospholipase A2-homologue myotoxin isolated from the venom of the snake Bothrops neuwiedii (yarara chica) from Argentina (1999) Toxicon, 37, pp. 1735-1746GINSBORG, B.L., WARRINER, J., The isolated chick biventer cervicis nerve-muscle preparation (1960) Brit. J. Pharmacol, 15, pp. 410-411HALPERT, J., EAKER, D., Amino acid sequence of a presynaptic neurotoxin from the venom of Notechis scutatus scutatus (Australian tiger snake) (1975) J. Biol. Chem, 250, pp. 6990-6997HARVEY AL., BARFARAZ A., THOMPSON E., FAIZ A., PRESTON S., HARRIS JB. Screening of snake venoms for neurotoxic and myotoxic effects using simple in vitro preparations from rodents and chicks. Toxicon, 1994, 32, 257-65HELUANY, N.F., HOMSI-BRANDEBURGO, M.I., GIGLIO, J.R., PRADO-FRANCESCHI, J., RODRIGUES-SIMIONI, L., Effects induced by bothropstoxin, a component from Bothrops jararacussu snake venom, on mouse and chick muscle preparations (1992) Toxicon, 30, pp. 1203-1210HOLZER, M., MACKESSY, S.P., An aqueous endpoint assay of snake venom phospholipase A2 (1995) Toxicon, 35, pp. 1149-1155HOMSI-BRANDEBURGO, M.I., QUEIROZ, L.S., SANTO-NETO, H., RODRIGUES-SIMIONI, L., GIGLIO, J.R., Fractionation of Bothrops jararacussu snake venom: Partial chemical characterization and biological activity of bothropstoxin (1988) Toxicon, 26, pp. 615-627JOHNSON, E.K., OWNBY, C.L., Isolation of a myotoxin from the venom of Agkistrodon contortrix laticinctus (broad-banded copperhead) and pathogenesis of myonecrosis induced by it in mice (1993) Toxicon, 31, pp. 243-255KAISER II, Gutierrez, J.M., Plummer, D., Aird, S.D., Odell, G.V., AIRD SD., ODELL GV. The amino acid sequence of a myotoxic phospholipase from the venom of Bothrops asper (1990) Arch. Biochem. Biophys, 278, pp. 319-325KATZ, B., MILEDI, R., The binding of acetylcholine to receptors and its removal from the synaptic cleft (1973) J. Physiol, 231, pp. 549-574KINI RM. Phospholipase A2 - A complex multifunctional protein puzzle. In: KINI RM. Ed., Venom phosholipase A2 enzymes. Structure, function and mechanism. New York: John Wiley &Sons Inc Chichester, 1997, 1-28KONDO, K., NARITA, K., LEE, C.Y., Amino acid sequences of the two polypeptide chains in beta1-bungarotoxin from the venom of Bungarus multicinctus (1978) J. Biochem, 83, pp. 101-115KONDO, K., TODA, H., NARITA, K., LEE, C.Y., Amino acid sequence of β2-bungarotoxin from Bungarus multicinctus venom: The amino acid substitutions in the B chains (1982) J. Biochem, 91, pp. 1519-1530KONDO, K., ZHANG, J., XU, K., KAGAMIYAMA, H., Amino acid sequence of a presynaptic neurotoxin, agkistrodotoxin, from the venom of Agkistrodon halys pallas (1989) J. Biochem, 105, pp. 196-203KORDAS, M., On the role of junctional cholinesterase in determining the time course of the end-plate current (1977) J. Physiol, 270, pp. 133-150LEE, C.Y., HO, C.L., BOTES, D.P., Site of action of caudoxin, a neurotoxic phospholipase A2 from the horned puff adder (Bitis caudalis) venom (1982) Toxicon, 20, pp. 637-647LIND, P., EAKER, D., Amino-acid sequence of the alpha-subunit of taipoxin, an extremely potent presynaptic neurotoxin from the Australian snake taipan (Oxyuranus s. scutellatus) (1982) European J. Biochem, 124, pp. 441-447MAGRO, A.J., SOARES, A.M., GIGLIO, J.R., FONTES, M.R., Crystal structures of BnSP-7 and BnSP-6, two Lys49 phospholipases A2: Quartenary structure and inhibition mechanism insights (2003) Biochem. Biophys. Res. Commun, 311, pp. 713-720MONTECUCCO, C., ROSSETTO, O., How do presynaptic PLA2 neurotoxins block nerve terminals? (2000) Trends Biochem. Sciences, 25, pp. 266-270OSHIMA-FRANCO, Y., HYSLOP, S., CINTRA, A.C., GIGLIO, J.R., DA CRUZ-HOFLING, M.A., RODRIGUES-SIMIONI, L., Neutralizing capacity of commercial bothropic antivenom against Bothrops jararacussu venom and bothropstoxin-I (2000) Muscle Nerve, 23, pp. 1832-1839OSHIMA-FRANCO, Y., LEITE, G.B., SILVA, G.H., CARDOSO, D.F., HYSLOP, S., GIGLIO, J.R., DA CRUZ-HOFLING, M.A., RODRIGUES-SIMIONI, L., Neutralization of the pharmacological effects of bothropstoxin-I from Bothrops jararacussu (jararacuçu) venom by crotoxin antiserum and heparin (2001) Toxicon, 39, pp. 1477-1485PEREIRA, M.F., NOVELLO, J.C., CINTRA, A.C., GIGLIO, J.R., LANDUCCI, E.T., OLIVEIRA, B., MARANGONI, S., The amino acid sequence of bothropstoxin-II, an Asp-49 myotoxin from Bothrops jararacussu (jararacuçu) venom with low phospholipase A2 activity (1998) J. Protein Chem, 17, pp. 381-386RE, L., BAROCCI, S., CAPITANI, C., VIVANI, C., RICCI, M., RINALDI, L., PAOLUCCI, G., MORALES, M.A., Effects of some natural extracts on the acetylcholine release at the mouse neuromuscular junction (1999) Pharmacol. Res, 39, pp. 239-245RE, L., COLA, V., FULGENZI, G., MARINELLI, F., CONCETTONI, C., ROSSINI, L., Postsynaptic effects of methoctramine at the mouse neuromuscular junction (1993) Neuroscience, 57, pp. 451-457RE, L., GIUSTI, P., CONCETTONI, C., DI SARRA, B., Computerized estimation of spontaneous and evoked acetylcholine release at the neuromuscular junction (1989) J. Pharmacol. Meth, 22, pp. 233-242RE, L., MORETTI, V., ROSSINI, L., GIUSTI, P., Sodium-activated potassium current in mouse diaphragm (1990) FEBS Lett, 270, pp. 195-197RIBEIRO, L.A., ALBUQUERQUE, M.J., PIRES DE CAMPOS VAF., KATZ G., TAKAOKAM NY., LEBRÃO ML., JORGE MT. Óbitos por serpentes peçonhentas no Estado de São Paulo: Avaliação de 43 casos, 1988/98 (1998) Rev. Assoc. Méd. Bras, 44, pp. 312-318RITONJA A., GUBENSEK F. Ammodytoxin A, a highly lethal phospholipase A2 from Vipera ammodytes ammodytes venom. Biochim. Biophys. Acta, 1985, 828, 306-12RODRIGUES-SIMIONI, L., BORGESE, N., CECCARELLI, B., The effects of Bothrops jararacussu venom and its components on frog nerve-muscle preparation (1983) Neuroscience, 10, pp. 475-489RODRIGUES-SIMIONI, L., ZAMUNER, S.R., COGO, J.C., BORJA-OLIVEIRA, C.R., PRADO-FRANCESCHI, J., CRUZ-HOFLING, M.A., CORRADO, A.P., Pharmacological evidence for a presynaptic action of venoms from Bothrops insularis (jararaca ilhoa) and Bothrops neuwiedi (jararaca pintada) (2004) Toxicon, 43, pp. 633-638SCHAGGER, H., VON JAGOW, G., Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the separation of proteins in the range from 1 to 100kDa (1987) Anal. Biochem, 166, pp. 368-379SOARES, A.M., GUERRA-SÁ, R., BORJA-OLIVEIRA, C.R., RODRIGUES, V.M., RODRIGUES-SIMIONI, L., RODRIGUES, V., FONTES, M.R.M., GIGLIO, J.R., Structural and functional characterization of BnSP-7, a Lys49 myotoxic phospholipase A2 homologue from Bothrops neuwiedi venom (2000) Arch. Biochem. Biophys, 378, pp. 201-209STÜHMER, W., ROBERTS, W.M., ALMERS, W., The loose patch clamp (1983) Single Channel Recording, p. 123. , SAKMANN B AND NEHER E, Eds, Plenum Press, New York;TOYAMA, M.H., SOARES, A.M., WEN-HWA, L., POLIKARPOV, I., GIGLIO, J.R., MARANGONI, S., Amino acid sequence of piratoxin-II, a myotoxic lys49 phospholipase A 2 homologue from Bothrops pirajai venom (2000) Biochimie, 82, pp. 245-250TSAI, I.H., LU, P.J., WANG, Y.M., HO, C.L., LIAW, L.L., Molecular cloning and characterization of a neurotoxic phospholipase A2 from the venom of Taiwan habu (Trimeresurus mucrosquamatus) (1995) Biochem. J, 311, pp. 895-900VAN DEN BERGH, C.J., SLOTBOOM, A.J., VERHEIJ, H.M., DE HAAS, G.H., The role of aspartic acid-49 in the active site of phospholipase A2. A site-specific mutagenesis study of porcine pancreatic phospholipase A 2 and the rationale of the enzymatic activity of Lys-49 phospholipase A2 from Agkistrodon piscivorus piscivorus venom (1988) European J. Biochem, 176, pp. 353-357VAN DEENEN LL, D.H.G., The substrate specificity of phospholipases A2 (1963) Biochim. Biophys. Acta, 70, pp. 538-553VILJOEN, C.C., BOTES, D.P., KRUGER, H., Isolation and amino acid sequence of caudoxin, a presynaptic acting toxic phospholipase A2 from the venom of the horned puff adder (Bitis caudalis) (1982) Toxicon, 20, pp. 715-737ZAMUNER, S.R., PRADO-FRANCESCHI, J., RODRIGUES-SIMIONI, L., The screening of Bothrops venoms for neurotoxic activity using the chick biventer cervicis preparation (1996) Toxicon, 34, pp. 314-31
Modeling the Subsurface Structure of Sunspots
While sunspots are easily observed at the solar surface, determining their
subsurface structure is not trivial. There are two main hypotheses for the
subsurface structure of sunspots: the monolithic model and the cluster model.
Local helioseismology is the only means by which we can investigate
subphotospheric structure. However, as current linear inversion techniques do
not yet allow helioseismology to probe the internal structure with sufficient
confidence to distinguish between the monolith and cluster models, the
development of physically realistic sunspot models are a priority for
helioseismologists. This is because they are not only important indicators of
the variety of physical effects that may influence helioseismic inferences in
active regions, but they also enable detailed assessments of the validity of
helioseismic interpretations through numerical forward modeling. In this paper,
we provide a critical review of the existing sunspot models and an overview of
numerical methods employed to model wave propagation through model sunspots. We
then carry out an helioseismic analysis of the sunspot in Active Region 9787
and address the serious inconsistencies uncovered by
\citeauthor{gizonetal2009}~(\citeyear{gizonetal2009,gizonetal2009a}). We find
that this sunspot is most probably associated with a shallow, positive
wave-speed perturbation (unlike the traditional two-layer model) and that
travel-time measurements are consistent with a horizontal outflow in the
surrounding moat.Comment: 73 pages, 19 figures, accepted by Solar Physic
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS
We present the results of a search for new, heavy particles that decay at a
significant distance from their production point into a final state containing
charged hadrons in association with a high-momentum muon. The search is
conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV
and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS
detector operating at the Large Hadron Collider. Production of such particles
is expected in various scenarios of physics beyond the standard model. We
observe no signal and place limits on the production cross-section of
supersymmetric particles in an R-parity-violating scenario as a function of the
neutralino lifetime. Limits are presented for different squark and neutralino
masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final
version to appear in Physics Letters
Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data
A measurement of the differential cross-section for the inclusive production
of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s)
= 7 TeV is presented. The measurement covers the pseudorapidity ranges
|eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV.
The results are based on an integrated luminosity of 35 pb-1, collected with
the ATLAS detector at the LHC. The yields of the signal photons are measured
using a data-driven technique, based on the observed distribution of the
hadronic energy in a narrow cone around the photon candidate and the photon
selection criteria. The results are compared with next-to-leading order
perturbative QCD calculations and found to be in good agreement over four
orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final
version published in Physics Letters
- …