0000000000667705

AUTHOR

H. Schmidt

showing 32 related works from this author

TID and SEE Tests of an Advanced 8 Gbit NAND-Flash Memory

2008

We report on the dose and operational mode dependence of error percentage, stand-by current, erase and write time of 8 Gbit / 4 Gbit NAND-flash memories as well as on their static, dynamic and SEFI cross sections.

Non-volatile memoryHardware_MEMORYSTRUCTURESComputer scienceNand flash memorybusiness.industryGigabitHardware_ARITHMETICANDLOGICSTRUCTURESbusinessComputer hardwareFlash memoryHardware_LOGICDESIGN2008 IEEE Radiation Effects Data Workshop
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Studies of Quantum Chromodynamics with the ALEPH Detector

1998

Previously published and as vet unpublished QCD results obtained with the ALEPH detector at LEP1 are presented. The unprecedented statistics allows detailed studies of both perturbative and non-perturbative aspects of strong interactions to be carried out using hadronic Z and tau decays. The studies presented include precise determinations of the strong coupling constant. tests of its flavour independence, tests of the SU(3) gauge structure of QCD, study of coherence effects, and measurements of single-particle inclusive distributions and two-particle correlations for many identified baryons and mesons. (C) 1998 Elsevier Science B.V.

AlephParticle physicsMesonHigh Energy Physics::LatticeElectron–positron annihilationHadronAleph; LEP; QCD; Quantum Chromo DynamicsGeneral Physics and Astronomy01 natural sciencesNuclear physicsQuantum Chromo Dynamics0103 physical sciencesBibliography010306 general physicsPhysicsQuantum chromodynamics010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyLEPBose–Einstein correlationsQCDALEPH detectorBaryonHigh Energy Physics::ExperimentAlephParticle Physics - Experiment
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Search for contact interactions in the reactionse + e −→l + l − ande + e −→γγ

1993

Contact interactions are searched for using the differential cross sections for the reactions e + e -→ e + e -, e + e -→ µ + µ -, e + e -→ τ + τ - and e + e -→γγ measured at 12 energies around the Z peak and corresponding to about 20 pb-1 of cumulated luminosity. Four-fermion contact term models assuming various chiralities of lepton currents are fitted to the lepton data and lower limits on the energy scale Λ of such terms are set at 95% c.l. The limits vary in the range 0.9 4.7 TeV, depending on the model and on the lepton flavour. The eeγγ contact terms are searched for assuming various chiralities. Limits on the energy scale Λ between 79 and 130 GeV are extracted from the data. The resu…

PhysicsRange (particle radiation)Particle physicsPhysics and Astronomy (miscellaneous)PhysicsElectron–positron annihilationHigh Energy Physics::PhenomenologyElementary particleLuminosityNuclear physicsALEPH ExperimentHigh Energy Physics::ExperimentField theory (psychology)Quantum field theoryEngineering (miscellaneous)ALEPH experimentLepton
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Ionic currents ofdrosophila embryonic neurons derived from selectively cultured CNS midline precursors

2000

In order to investigate the electrogenesis of defined cell populations, we applied an in vitro system that allows the selective culturing of individual Drosophila CNS precursors under different conditions. CNS midline (ML) precursors prepared from gastrula stage embryos gave rise to progeny cells with neuronal and glial morphology that expressed specific markers. Using whole-cell patch-clamp recordings, a detailed description of ionic currents present in this defined cell population is provided. Most ionic currents of cultured ML neurons were similar to other cultured Drosophila neurons, even though their embryonic origin is different. They displayed at least two voltage-gated potassium cur…

education.field_of_studyGeneral NeurosciencePopulationCellchemistry.chemical_elementEmbryoDepolarizationCalciumBiologyEmbryonic stem cellIn vitroCell biologyGastrulationCellular and Molecular Neurosciencemedicine.anatomical_structurechemistrymedicineeducationNeuroscienceJournal of Neurobiology
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Measurement of the b → τ-ν̄τX branching ratio

1993

The definitions of “anthropology” found in various dictionaries cover a whole range of terms and in this section we provide an overview of all its connotations. In this way a variety of reflections about the essence of man become possible, for instance as : summit of creation; source of his own values; specific biological reality; intelligence (but what is this, really?); knowing subject or object of knowledge; social being and product of a culture. Following these lines of thought one realises that all these preoccupations have already been taken up, or at least touched upon, by communication theory.

PhysicsNuclear and High Energy PhysicsParticle physicsgeographySummitgeography.geographical_feature_categoryE+E ANNIHILATION010308 nuclear & particles physicsSection (typography)Subject (philosophy)Variety (linguistics)01 natural sciencesObject (philosophy)DECAYSCommunication theoryEpistemologyProduct (mathematics)0103 physical sciencesCover (algebra)010306 general physics
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Search for high mass photon pairs in (f= e, μ, τ, v, q) at LEP

1993

Abstract The result of a search for high mass photon pairs from the processes e + e − → f f γγ (f = e, μ, τ, v and q) with the ALEPH detector is reported. The result for f = e , μ and τ is to be compared with the observation of 4 events by the L3 Collaboration with invariant masses, M γγ , of the two photons near 60 GeV. From a data sample approximately twice as large taken from 1990 to 1992, 6 events are found with M γγ distributed between 50 GeV and 72 GeV, while 4.9 events are expected from a QED calculation. There is no evidence for a mass peak; only one event ( μ + μ − γγ ) at M γγ = 59.4 ± 0.2 GeV is compatible with the L3 observation. In addition, for M γγ > 50 GeV, no event is found…

Nuclear physicsPhysicsNuclear and High Energy PhysicsParticle physicsHigh energyPhotonElectron–positron annihilationHigh massALEPH experimentPhysics Letters B
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Search for a new weakly interacting particle

1991

Abstract A search for events of the type e + e − →l + l − X 0 , where X 0 can be any weakly interacting particle which couples to the Z, has been performed with the ALEPH detector at LEP, by searching for acollinear lepton pairs. Such particles can be excluded up to a mass of 7.0 GeV/c 2 for a value of the ratio of branching fractions, Br( Z →X 0 l + l − )/Br(Z→ l + l − ), greater than 2.5 × 10 −3 if the X 0 has third component of isospin, I 3 greater than 1 2 and decays to a pair of virtual gauge bosons. When this analysis is combined with the previous results of the Higgs particle searches from ALEPH, this limit can be extended to an X 0 mass of 60 GeV/c 2 .

PhysicsNuclear physicsNuclear and High Energy PhysicsAlephParticle physicsGauge bosonIsospinElectron–positron annihilationHigh Energy Physics::PhenomenologyHiggs bosonHigh Energy Physics::ExperimentParticle Physics - ExperimentLepton
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Abstract of the 68th Meeting (Spring Meeting) 6–9 March 1990, Heidelberg

1990

0303 health sciencesPhysiologyChemistryClinical BiochemistryTibialis AnteriorHuman physiology030204 cardiovascular system & hematologyPharmacologySpring (mathematics)ArticleAtrial Natriuretic Peptide03 medical and health sciences0302 clinical medicineAtrial natriuretic peptidePhysiology (medical)Spreading DepressionCapsaicinExtensor Digitorum Longus030304 developmental biologyPflugers Archiv
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Influence of polymer content in Ca-deficient hydroxyapatite–polycaprolactone nanocomposites on the formation of microvessel-like structures

2009

Calcium phosphate (CaP) ceramics are widely used in bone tissue engineering due to their good osteoconductivity. The mechanical properties of CaP can be modified by the addition of small volume fractions of biodegradable polymers such as polycaprolactone (PCL). Nevertheless, it is also important to evaluate how the polymer content influences cell-material or cell-cell interactions because of potential consequences for bone regeneration and vascularization. In this study we assessed the general biocompatibilty of Ca-deficient hydroxyapatite (CDHA)-PCL disks containing nominally 11 and 24% polycaprolactone using human umbilical vein endothelial cells and human primary osteoblasts. Confocal mi…

Materials scienceAngiogenesisPolyestersBiomedical EngineeringNeovascularization Physiologicchemistry.chemical_elementBiocompatible Materialsmacromolecular substancesCalciumBiochemistryUmbilical veinNanocompositeslaw.inventionBiomaterialschemistry.chemical_compoundConfocal microscopylawHumansBone regenerationMolecular BiologyMicrovesselCell ProliferationOsteoblastsReverse Transcriptase Polymerase Chain Reactiontechnology industry and agricultureEndothelial CellsGeneral MedicineAlkaline Phosphataseequipment and suppliesmusculoskeletal systemBiodegradable polymerCoculture TechniquesDurapatitechemistryMicrovesselsPolycaprolactoneCalciumBiomarkersBiotechnologyBiomedical engineeringActa Biomaterialia
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Measurement of the ratio using event shape variables

1993

Abstract The branching fraction of Z → b b relative to all hadronic decays of the Z has been measured using event shape variables to preferentially select Z → b b events. The method chosen applies a combination of shape discriminators and the selection of high transverse momentum leptons to event hemispheres. From a sample of 440 000 hadronic Z decays collected with the ALEPH detector at LEP, the ration Γ b b Γ had = 0.228±0.005( stat. )±0.005( syst. ) is measured.

PhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsBranching fractionHadronElementary particle01 natural sciences0103 physical sciencesTransverse momentumHigh Energy Physics::ExperimentNuclear Experiment010306 general physicsALEPH experimentLeptonBar (unit)Event (probability theory)Physics Letters B
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TRACKING WITH THE ALEPH TIME PROJECTION CHAMBER

1991

The tracking performance of the ALEPH time projection chamber (TPC) has been studied using the data taken during the LEP (Large Electron-Positron Collider) running periods in 1989 and 1990. After careful correction of residual distortions and optimization of coordinate reconstruction algorithms, a single coordinate resolution of 173 mu m in the azimuthal and 740 mu m in the longitudinal direction is achieved. This results in a momentum resolution for the TPC alone of Delta p/p/sup 2/=0.0012 (GeV/c)/sup -1/. In combination with the ALEPH inner tracking chamber (ITC), a total momentum resolution of Delta p/p/sup 2/=0.0008 (GeV/c)/sup -1/, close to the design specifications, is reached. >

PhysicsNuclear and High Energy PhysicsMomentum (technical analysis)AlephTime projection chamberPhysics::Instrumentation and DetectorsParticle acceleratorTracking (particle physics)Particle detectorlaw.inventionNuclear physicsAzimuthNuclear Energy and EngineeringlawHigh Energy Physics::ExperimentElectrical and Electronic EngineeringCollider
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Search for a non-minimal Higgs boson produced in the reaction →

1993

Abstract A data sample corresponding to 1.23 million hadronic Z decays collected by the ALEPH detector at LEP has been searched for signals of the production of a non-minimal CP-even Higgs boson h in the reaction e + e − → hZ ∗ . The h decay modes considered were: those of the minimal standard model Higgs boson, with modified branching ratios; decays into a pair of CP-odd Higgs bosons A; and decays into invisible final states. Only one event was found, a very acoplanar e+e− pair which could originate from the standard model background process e + e − → e + e − v v . Upper limits for the cross-section of the reaction e + e − → hZ ∗ have been derived as a function of mh, the mass of the Higgs…

PhysicsNuclear and High Energy PhysicsAlephParticle physicsElectron–positron annihilationHigh Energy Physics::PhenomenologyHadronElementary particleSupersymmetryNuclear physicsHiggs bosonHigh Energy Physics::ExperimentALEPH experimentBosonPhysics Letters B
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Heavy ion SEE studies on 4-Gbit NAND-Flash memories

2007

Heavy ion SEE studies on three 4-Gbit NAND-flash memory types were performed at the RADEF facility at the University of Jyvaskyla, Finland with particular emphasis on SEFI differentiation. An error classification for complex memory devices is introduced, and respective cross sections are reported.

Flash (photography)Hardware_MEMORYSTRUCTURESComputer scienceGigabitEmphasis (telecommunications)Electronic engineeringNAND gateHeavy ionTransient analysisFlash memory2007 9th European Conference on Radiation and Its Effects on Components and Systems
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Measurement of the and B− meson lifetimes

1993

Abstract The lifetimes of the B 0 and B − mesons have been measured with the ALEPH detector at LEP. Semileptonic decays of B 0 and B − mesons were partially reconstructed by identifying events containing a lepton with an associated D ∗+ or D 0 meson. The proper time of the B meson was estimated from the measured decay length and the momentum and mass of the D -lepton system. A fit to the proper time of 77 D ∗+ l − and 77 D 0 l − candidates, combined with a constraint on the lifetime ratio ( τ − τ 0 ) arising from the relative rates of observed D ∗+ l − and D 0 l − events, yielded the following lifetimes: τ 0 =1.52 −0.18 +0.20 ( stat. ) −0.13 +0.07 ( syst. ) ps , τ − = 1.47 −0.19 +0.22 ( sta…

Semileptonic decayPhysicsNuclear and High Energy PhysicsParticle physicsMeson010308 nuclear & particles physicsElectron–positron annihilationNuclear TheoryHigh Energy Physics::Phenomenology01 natural sciencesNuclear physicsMomentum0103 physical sciencesDecay lengthProper timeHigh Energy Physics::ExperimentB mesonNuclear Experiment010306 general physicsLepton
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Measurement of the branching ratio and an upper limit on

1995

Abstract Using 1.45 million hadronic Z decays collected by the ALEPH experiment at LEP, the b → τ − ν - τ X branching ratio is measured to be 2.75 ± 0.30 ± 0.37%. In addition an upper limit of 1.8 × 10 −3 at 90% confidence level is placed upon the exclusive branching ratio of B − → τ − ν - τ . These measurements are consistent with SM expectations, and put the constraint tan β M h ± GeV −1 at 90% confidence level on all Type II two Higgs doublet models (such as the MSSM).

ALEPH ExperimentNuclear physicsPhysicsNuclear and High Energy PhysicsBranching fractionElectron–positron annihilationHadronHiggs bosonLimit (mathematics)SupersymmetryALEPH experimentPhysics Letters B
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Probleme der Stadieneinteilung beim fortgeschrittenen Blasentumor

1988

Eine bis zu 50% reichende Unterschatzung der Blasencarcinome in den Stadien pTa bis hin zum Stadium pT3a, eine uber 50% reichende Uberschatzung der Stadien pT3b und pT4 und eine richtige Aussage in nur 44% der Falle kennzeichnen die Problematik der exakten klinischen Stadienerfassung von Blasentumoren in der „Vor-CT-Aera“ [2].

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Measurement of the strong coupling constant using τ decays

1993

The strong coupling constant is determined from the leptonic branching ratios, the lifetime, and the invariant mass distribution of the hadronic final state of the tau lepton, using data accumulated at LEP with the ALEPH detector. The strong coupling constant measurement, alpha(s), (m(tau)2) = 0.330 +/-0.046, evolved to the Z mass, yields alpha(s)(M(Z)2) = 0. 1 18 +/- 0.005. The error includes experimental and theoretical uncertainties, the latter evaluated in the framework of the Shifman, Vainshtein and Zakharov (SVZ) approach. The method allows the non-perturbative contribution to the hadronic decay rate to be determined to be 0.3 +/- 0.5% . RI Perrier, Frederic/A-5953-2011; ANTONELLI, AN…

PhysicsCoupling constantNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsElectron–positron annihilationPhysicsknowledge discoveryHigh Energy Physics::PhenomenologyDetectorHadronStrong interaction01 natural sciencesALEPH ExperimentNuclear physics0103 physical sciences[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]High Energy Physics::ExperimentInvariant massbibliographic databases010306 general physicsALEPH experimentParticle Physics - ExperimentLepton
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Production and decay of charmed mesons at the Z resonance

1991

Abstract In a sample of 190 000 hadronic Z decays, three signals of charm production are observed: two from the exclusive decays D ° → K − π + and D ∗+ → D °π + → K − π + π + and one in the transverse-momentum distribution of soft hadrons relative to the nearest jet. The features of these signals are in good agreement with expectations based on the standard model and previous measurements of the branching fractions. The number of D ∗± → K ± π ± π ± per hadronic decay of the Z is measured to be (5.11±0.34) × 10 −3 , and the branching ratio B(D 0 → K − π + ) is (3.62 ± 0.34 ± 0.44)%. Charm hadronization has been studied. The average fraction of the beam energy carried by the D ∗ meson is foun…

Nuclear physicsPhysicsHadronic decayNuclear and High Energy PhysicsParticle physicsMesonBranching fractionElectron–positron annihilationHadronBeam energyParticle Physics - ExperimentHadronization
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Poster contributions

1989

Nuclear and High Energy PhysicsMaterials sciencePhysical and Theoretical ChemistryCondensed Matter PhysicsAtomic and Molecular Physics and OpticsHyperfine Interactions
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Correlation measurements in Z→τ+τ− and the τ neutrino helicity

1994

Using data collected with the ALEPH detector at LEP correlations between the decay products of the τ+ and τ- produced in the decay of the Z have been measured. The measurements performed in the decays τ-->πν and τ-->ϱν place limits on deviations from the Standard Model. These are given by the parameter ζ with ζ = -1 for the Standard Model. The measured values are ζπ = -0.95 +/- 0.11 +/- 0.05 and ζϱ = -1.03 +/- 0.11 +/- 0.05. For models which predict ζπ = ζϱ = ζ - interpreted as the average τ neutrino helicity - the measurement is ζ = -0.99 +/- 0.07 +/- 0.04.

PhysicsNuclear and High Energy PhysicsParticle physics010308 nuclear & particles physicsElectron–positron annihilationElementary particle01 natural sciencesHelicityNuclear physicsALEPH Experiment0103 physical sciencesNeutrino010306 general physicsALEPH experiment
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PERFORMANCE OF THE ALEPH TIME PROJECTION CHAMBER

1991

The performance of the ALEPH Time Projection Chamber (TPC) has been studied using data taken during the LEP running periods in 1989 and 1990. After correction of residual distortions and optimisation of coordinate reconstruction algorithms, single coordinate resolutions of 173-mu-m in the azimuthal and 740-mu-m in the longitudinal direction are achieved. This results in a momentum resolution for the TPC of DELTA-p/p2 = 1.2 x 10(-3) (GeV/c)-1. In combination with the ALEPH Inner Tracking Chamber (ITC), a total momentum resolution of DELTA-p/p2 = 0.8 x 10(-3) (GeV/c)-1 is obtained. With respect to particle identification, the detector achieves a resolution of 4.4% for the measurement of the i…

PhysicsNuclear and High Energy PhysicsTime projection chamberPhysics::Instrumentation and DetectorsTracking (particle physics)Particle identificationParticle detectorMomentumNuclear physicsAzimuthPair productionHigh Energy Physics::ExperimentDetectors and Experimental TechniquesInstrumentationImage resolution
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Scientific Proceedings Second International Symposium on Cytostatic Drug Resistance

1991

Cancer Researchmedicine.medical_specialtyOncologybusiness.industrymedicineGeneral MedicineDrug resistancePharmacologyIntensive care medicinebusinessJournal of Cancer Research and Clinical Oncology
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Measurement of the B hadron lifetime

1991

The average lifetime of B hadrons has been measured by the ALEPH experiment at LEP. Events containing B hadrons are selected by the identification of leptons with high transverse momentum in hadronic Z decays, and the lifetime is extracted from a fit to the impact parameter distribution of the lepton tracks. From a sample of 1.7×105 hadronic Z decays a lifetime of 1.29±0.06±0.10 ps is measured.

PhysicsNuclear and High Energy PhysicsParticle physicsMesonElectron–positron annihilationHigh Energy Physics::PhenomenologyHadronElementary particleNuclear physicsHigh Energy Physics::ExperimentB mesonImpact parameterNuclear ExperimentALEPH experimentParticle Physics - ExperimentLeptonPhysics Letters B
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Measurement of B- mixing at the Z

1991

Abstract From more than 175 000 hadronic Z decays observed with the ALEPH detector at LEP, we select 823 events with pairs of leptons in the final state. From these we measure χ , the probability thata b hadron which is observed to decay originated as a b hadron. We find χ =0.132 −0.026 +0.027 .

PhysicsNuclear and High Energy PhysicsParticle physicsAlephElectron–positron annihilationHigh Energy Physics::PhenomenologyHadronDecision makerMeasure (mathematics)Nuclear physicsHigh Energy Physics::ExperimentNuclear ExperimentMixing (physics)LeptonPhysics Letters B
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Measurement of the strong coupling constant alfa_s from global event-shape variables of hadronic Z decays

1991

Abstract An analysis of global event-shape variables has been carried out for the reaction e+e−→Z0→hadrons to measure the strong coupling constant αs. This study is based on 52 720 hadronic events obtained in 1989/90 with the ALEPH detector at the LEP collider at energies near the peak of the Z-resonance. In order to determine αs, second order QCD predictions modified by effects of perturbative higher orders and hadronization were fitted to the experimental distributions of event-shape variables. From a detailed analysis of the theoretical uncertainties we find that this approach is best justified for the differential two-jet rate, from which we obtain αs(MZ2) = 0.121 ± 0.002(stat.)±0.003(s…

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsElectron–positron annihilationHadronMeasure (mathematics)Hadronizationlaw.inventionNuclear physicsRenormalizationlawHigh Energy Physics::ExperimentColliderConstant (mathematics)Particle Physics - Experiment
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Comparative study assessing effects of sonic hedgehog and VEGF in a human co-culture model for bone vascularisation strategies.

2011

The morphogen sonic hedgehog (Shh) seems to mediate adult repair processes in bone regeneration and vascularisation. In this study we investigated the effects of Shh on co-cultures consisting of human primary osteoblasts and outgrowth endothelial cells in terms of angiogenic activation and vessel maturation in comparison to the treatment with the commonly used proangiogenic factor, VEGF. Both, stimulation with VEGF or Shh, leads to an increase in the formation of microvessel-like structures compared to untreated controls. In contrast to VEGF, proangiogenic effects by Shh could already be observed after 24 h of treatment. Nevertheless, after 14 days the angiogenic activity of OEC was compara…

Vascular Endothelial Growth Factor Alcsh:Diseases of the musculoskeletal systemBone Regenerationmedicine.medical_treatmentFluorescent Antibody TechniqueAngiogenesis InhibitorsPolymerase Chain ReactionneovascularisationBasement MembraneDesminchemistry.chemical_compoundTransforming Growth Factor betaReceptors Platelet-Derived Growth FactorSonic hedgehogbiologyCell biologyUp-Regulationembryonic structuresElectrophoresis Polyacrylamide GelMorphogenmedicine.medical_specialtyanimal structuressignalling moleculesCyclopamineBlotting Westernlcsh:SurgeryNeovascularization PhysiologicEnzyme-Linked Immunosorbent AssayBone and BonesDownregulation and upregulationInternal medicinemedicineAngiopoietin-1HumansHedgehog ProteinsBone regenerationOsteoblastsGrowth factorEndothelial Cellslcsh:RD1-811bone repairco-cultureActinsCoculture TechniquesEndocrinologychemistryMyocardinbiology.proteinDesminlcsh:RC925-935AngiopoietinsEuropean cellsmaterials
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Measurement of Prompt Photon Production In Hadronic-z Decays

1993

The production of isolated photons in hadronic Z decays is measured with the ALEPH detector at LEP using a sample of 450 000 hadronic events. The corrected rate is given for several values of the minimum invariant mass squared cut between the photon and the jets. This measurement of final state radiation from the quarks is compared with the predictions of parton shower models JETSET, ARIADNE and HERWIG as well as with the predictions of QCD matrix element calculations. RI Perrier, Frederic/A-5953-2011; ANTONELLI, ANTONELLA/C-6238-2011; Buttar, Craig/D-3706-2011; Stahl, Achim/E-8846-2011; Passalacqua, Luca/F-5127-2011; Murtas, Fabrizio/B-5729-2012; St.Denis, Richard/C-8997-2012; Forti, Franc…

PhysicsQuantum chromodynamicsQuarkbusiness recordsParticle physicsAlephPhotonPhysics and Astronomy (miscellaneous)010308 nuclear & particles physicsrecords managementElectron–positron annihilationPhysicsHigh Energy Physics::PhenomenologyHadron01 natural sciencesNuclear physics0103 physical sciencesretention schedule[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]High Energy Physics::ExperimentInvariant mass010306 general physicsParton showerEngineering (miscellaneous)Particle Physics - Experiment
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An experimental study of γγ → hadrons at LEP

1993

An analysis of γγ interactions has been performed using untagged hadronic data obtained by the ALEPH detector at LEP. The data show at low transverse momentum (pt) are well reproduced by a model based on the vector meson dominance mechinism (VDM). At high pt thrust the presence of hard scattering processes is demonstrated. This component is well described in shape and normalization by a QCD calculation.

Quantum chromodynamicsPhysicsNormalization (statistics)Nuclear and High Energy PhysicsParticle physicsROSS-SECTIONE+E-PHYSICSScatteringHigh Energy Physics::PhenomenologyHadronElementary particleVector meson dominancePhoton structure functionJET FRAGMENTATIONNuclear physicsALEPH ExperimentPHOTONLUND MONTE-CARLOCSCATTERINGHigh Energy Physics::ExperimentALEPH experiment
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A precise measurement of ΓZ→bb/ΓZ→hadrons

1993

A measurement of the partial width ratio Γbb/Γhad using a method which tags the Z --> bb decays through the lif etime of the produced heavy hadrons is presented. This method relies on the tracking precision afforded by a double-sided silicon vertex detector. The tag algorithm makes a probabilistic interpretation of three-dimensional track impact parameters, using the data to measure the resolution. By tagging the two b hadrons separately, both Γbb/Γhad and the tag efficiency can be determined from the data. For a 26% efficiency of tagging a single b hadron within the vertex detector solid angle coverage, a purity of 96% is achieved. A value of Γbb/Γhad = 0.2192+/-0.0026(stat.)+/-0.0016(Γcc/…

PhysicsNuclear and High Energy PhysicsParticle physicsPhysicsElectron–positron annihilationHadronSolid angleElementary particleTracking (particle physics)b-taggingStandard ModelALEPH ExperimentNuclear physicsHigh Energy Physics::ExperimentALEPH experimentPhysics Letters B
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Inclusive π±, K± and(p,p¯) differential cross-sections at the Z resonance

1995

Inclusive π±, K± and $$(p,\bar p)$$ differential cross-sections in hadronic decays of the Z have been measured as a function ofz=P hadron/P beam, the scaled momentum. The results are based on approximately 520 000 events measured by the ALEPH detector at LEP during 1992. Charged particles are identified by their rate of ionization energy loss in the ALEPH Time Projection Chamber. The position, ξ*, of the peak in the ln(1/z) distribution is determined, and the evolution of the peak position with centre-of-mass energy is compared with the prediction of QCD.

Quantum chromodynamicsPhysicsParticle physicsTime projection chamberPhysics and Astronomy (miscellaneous)Electron–positron annihilationHigh Energy Physics::PhenomenologyHadronResonance (particle physics)Charged particleNuclear physicsMomentumALEPH ExperimentHigh Energy Physics::ExperimentEngineering (miscellaneous)ALEPH experiment
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Search for the standard model Higgs boson

1993

Using a data sample corresponding to about 1 233 000 hadronic Z decays collected by the ALEPH experiment at LEP, the reaction e+e- --> HZ* has been used to search for the standard model Higgs boson, in association with missing energy when Z* --> nunuBAR, or with a pair of energetic leptons when Z* --> e+e- or mu+mu-. No signal was found and, at the 95% confidence level, m(H) exceeds 58.4 GeV/c2. RI ANTONELLI, ANTONELLA/C-6238-2011; Buttar, Craig/D-3706-2011; Stahl, Achim/E-8846-2011; Passalacqua, Luca/F-5127-2011; Murtas, Fabrizio/B-5729-2012; St.Denis, Richard/C-8997-2012; Forti, Francesco/H-3035-2011; Ferrante, Isidoro/F-1017-2012

Nuclear and High Energy PhysicsParticle physics[PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex]Electron–positron annihilationHadronElementary particle01 natural sciencesinternet searchingdistance calculationsStandard ModelALEPH Experiment0103 physical sciencesgraph applications.[PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex]010306 general physicsALEPH experimentPhysicsMissing energy010308 nuclear & particles physicsPhysicsHigh Energy Physics::Phenomenologymetric spacelcsh:QC1-999Higgs bosonHigh Energy Physics::Experimentlcsh:PhysicsParticle Physics - ExperimentLepton
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Meta-analysis of 74,046 individuals identifies 11 new susceptibility loci for Alzheimer's disease

2013

Eleven susceptibility loci for late-onset Alzheimer's disease (LOAD) were identified by previous studies; however, a large portion of the genetic risk for this disease remains unexplained. We conducted a large, two-stage meta-analysis of genome-wide association studies (GWAS) in individuals of European ancestry. In stage 1, we used genotyped and imputed data (7,055,881 SNPs) to perform meta-analysis on 4 previously published GWAS data sets consisting of 17,008 Alzheimer's disease cases and 37,154 controls. In stage 2, 11,632 SNPs were genotyped and tested for association in an independent set of 8,572 Alzheimer's disease cases and 11,312 controls. In addition to the APOE locu…

MaleApolipoprotein Eepidemiology [Alzheimer Disease]SORL1Medizingenetics [Alzheimer Disease]Genome-wide association studySingle-nucleotide polymorphismBiologyPolymorphism Single NucleotideArticlePICALMCohort StudiesAlzheimer Diseaseddc:570PSEN2GeneticsmedicineHumansGenetic Predisposition to DiseaseAge of OnsetBiologyAgedGenetic associationAged 80 and overGeneticsMiddle Agedmedicine.diseaseGenetic LociCase-Control StudiesFemaleHuman medicineAlzheimer's diseasestatistics & numerical data [Genome-Wide Association Study]Genome-Wide Association StudyNature Genetics
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