Publications by authors named "Schumann J"

We have searched for the decay B+-->omegal(+)nu (l=e or mu) in 78 fb(-1) of Upsilon(4S) data (85x10(6)BB events) accumulated with the Belle detector. The final state is fully reconstructed using the omega decay into pi(+)pi(-)pi(0), combined with detector hermeticity to estimate the neutrino momentum. A signal of 414+/-125 events is found in the data, corresponding to a branching fraction of (1.

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We present the first evidence of the decay B0-->rho(0)pi(0), using 140 fb(-1) of data collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric e(+)e(-) collider. We detect 15.1+/-4.

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We report the first observation of CP violation in B0-->pi(+)pi(-) decays based on 152x10(6) gamma (4S)-->BB decays collected with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We reconstruct a B0-->pi(+)pi(-) CP eigenstate and identify the flavor of the accompanying B meson from its decay products. From the distribution of the time intervals between the two B meson decay points, we obtain A(pipi)=+0.

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Direct CP violation in the b-->sgamma process is a sensitive probe of physics beyond the standard model. We report a measurement of the CP asymmetry in B-->X(s)gamma, where the hadronic recoil system X(s) is reconstructed using a pseudoreconstruction technique. In this approach there is negligible contamination from b-->dgamma decays, which are expected to have a much larger CP asymmetry.

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We report measurements of time dependent decay rates for B0(B(0))-->D((*)-/+)pi(+/-) decays and extraction of CP violation parameters containing phi(3). Using fully reconstructed D((*))pi events from a 140 fb(-1) data sample collected at the Upsilon(4S) resonance, we obtain the CP violation parameters for D(*)pi and Dpi decays, 2R(D((*))pi)sin((2phi(1)+phi(3)+/-delta(D((*))pi)), where R(D((*))pi) is the ratio of the magnitudes of the doubly Cabibbo-suppressed and Cabibbo-favored amplitudes, and delta(D((*))pi) is the strong phase difference between them. Under the assumption of delta(D((*))pi) being close to either 0 degrees or 180 degrees, we obtain |2R(D(*)pi)sin((2phi(1)+phi(3))|=0.

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We have performed a search for the lepton-flavor-violating decay tau-->microgamma using a data sample of 86.3 fb(-1) accumulated by the Belle detector at KEK. No evidence for a signal is seen, and we set an upper limit for the branching fraction of B(tau-->microgamma)<3.

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We report the observation of the decay D0-->phigamma with a statistical significance of 5.4sigma in 78.1 fb(-1) of data collected by the Belle experiment at the KEKB e+e- collider.

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The radiative decay B-->phi K gamma is observed for the first time. The branching fraction for the charged B--->phi K- gamma decay mode is measured to be B(B--->phi K- gamma)=(3.4+/-0.

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Pseudomonas aeruginosa exotoxin A (PEA) causes T cell- and Kupffer cell (KC)-dependent liver injury in mice. TNF-alpha as well as IL-18 and perforin are important mediators of liver damage following PEA injection. In this study, we focus on the role of NK and NKT cells in PEA-induced liver toxicity.

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We report evidence for the decay B0-->pi(0)pi(0). The analysis is based on a data sample of 152x10(6) BBmacr; pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring. We detect a signal for B0-->pi(0)pi(0) with a significance of 3.

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We present an improved measurement of CP-violation parameters in B0-->phiK(0)(S), K(+)K(-)K(0)(S), and eta(')K(0)(S) decays based on a 140 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. One neutral B meson is fully reconstructed in one of the specified decay channels, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters for each of the three modes are obtained from the asymmetries in the distributions of the proper-time intervals between the two B decays.

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We report the observation of the flavor-changing neutral current decay B-->K(*)l(+)l(-) and an im-proved measurement of the decay B-->Kl(+)l(-), where l represents an electron or a muon, with a data sample of 140 fb(-1) accumulated at the Upsilon(4S) resonance with the Belle detector at KEKB. The results for the branching fractions are B(B-->K(*)l(+)l(-))=(11.5(+2.

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We present the first measurement of decay amplitudes in B-->phiK* and measurements of branching fractions in B-->phiK(*) decays based on 78.1 fb(-1) of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e+e- storage ring. The decay amplitudes for the different phiK*0 helicity states are measured from the angular distributions of final state particles in the transversity basis.

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We report the first observation of the charmless vector-vector decay process B-/+-->rho(-/+)rho(0). The measurement uses a 78 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider operating at the Upsilon(4S) resonance. We obtain a branching fraction of B(B-/+-->rho(-/+)rho(0))=[31.

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We report evidence for the decay mode B-->phiphiK based on an analysis of 78 fb(-1) of data collected with the Belle detector at KEKB. This is the first example of a b-->sssss transition. The branching fraction for this decay is measured to be B(B+/--->phiphiK+/-)=(2.

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Background/aims: Silibinin is the major pharmacologically active compound of the Silybum marianum fruit extract silymarin. Its well-known hepatoprotective activities are mostly explained by antioxidative properties, inhibition of phosphatidylcholine synthesis or stimulation of hepatic RNA and protein synthesis. Here, we characterized the hepatoprotective potential of silibinin as an immune-response modifier in T cell-dependent hepatitis in vivo.

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In modern materials science the characterisation of nanostructures is becoming increasingly important. For measurement of the quality of nanoscale multilayer arrangement with high spatial resolution a method is described that is based on the broadening of the spots in the Fourier transformation of transmission electron microscopic images of multilayer cross-sections. Using this method on Si/Ge superlattices with periodic lengths between 4 and 12 nm it could be quantitatively shown that the layer perfection decreases with increasing periodic length.

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CD1d tetramers loaded with alpha-galactosylceramide (alpha-GalCer) bind selectively to mouse invariant Valpha14 (Valpha14i) NKT cells and their human counterparts. Whereas tetramer binding strictly depends on the expression of a Valpha14-Jalpha18 chain in murine NKT cells, the associated beta-chain (typically expressing Vbeta8.2 or Vbeta7) appears not to influence tetramer binding.

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We report the first observation of the charmless hyperonic B decay, B0-->pLambda(pi)(-), using a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. The measured branching fraction is B(B0-->pLambda(pi)(-))=(3.97(+1.

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We report on a search for B(0)-->D(*0)K(*0) decays based on 85 x 10(6) BB events collected with the Belle detector at KEKB. The B(0)-->D0K(0) and B(0)-->D0K(*0) decays have been observed for the first time with the branching fractions B(B(0)-->D0K(0))=(5.0(+1.

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We report the measurement of the charmed baryonic decay B(0)-->Lambda(+)(c)p with a branching fraction of (2.19(+0.56)(-0.

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In addition to their CD1d-restricted T cell receptor (TCR), natural killer T (NKT) cells express various receptors normally associated with NK cells thought to act, in part, as modulators of TCR signaling. Immunoreceptor-tyrosine activation (ITAM) and inhibition (ITIM) motifs associated with NK receptors may augment or attenuate perceived TCR signals respectively, potentially influencing NKT cell development and function. ITIM-containing Ly49 family receptors expressed by NKT cells are proposed to play a role in their development and function.

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A sizable fraction of T cells expressing the NK cell marker NK1.1 (NKT cells) bear a very conserved TCR, characterized by homologous invariant (inv.) TCR V alpha 24-J alpha Q and V alpha 14-J alpha 18 rearrangements in humans and mice, respectively, and are thus defined as inv.

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TNF-alpha is a central mediator of T cell activation-induced hepatitis in mice, e.g., induced by Pseudomonas exotoxin A (PEA).

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Anomalies in the nanostructure evolution of ReSi(2+/-x) thin films have proved to be of large interest in connection with their thermoelectric properties. By means of electron microscopic methods the correlation between structural properties and transport behaviour has been studied. The short-range order of the amorphous state was characterised by reduced density functions calculated from diffuse electron diffraction diagram and is found to correlate with the temperature dependence of the electrical resistance.

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