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The deflagration-to-detonation transition in a 100 mm square cross-section channel was investigated for a highly reactive stoichiometric hydrogen oxygen mixture at 70 kPa. Obstacles of 5 mm width and 5, 10, and 15 mm heights were equally spaced 60 mm apart at the bottom of the channel. The phenomenon was investigated primarily by time-resolved schlieren visualization from two orthogonal directions using a high-speed video camera. The detonation transition occurred over a remarkably short distance within only three or four repeated obstacles. The global flame speed just before the detonation transition was well below the sound speed of the combustion products and did not reach the sound speed of the initial unreacted gas for tests with an obstacle height of 5 and 10 mm. These results indicate that a detonation transition does not always require global flame acceleration beyond the speed of sound for highly reactive combustible mixtures. A possible mechanism for this detonation initiation was the mixing of the unreacted and reacted gas in the vicinity of the flame front convoluted by the vortex present behind each obstacle, and the formation of a hot spot by the shock wave. The final onset of the detonation originated from the unreacted gas pocket, which was surrounded by the obstacle downstream face and the channel wall.

In this paper, a preliminary result from the latest hypernuclear γ -ray spectroscopy experiment (KEK-E566) is presented together with a short discussion. The experiment was performed at the KEK-PS K6 beam line in 2005. In this experiment, the 12C(π+, K +)12 ΛC reaction was employed to populate 12 ΛC/11 ΛB hypernuclei. A germanium detector array, Hyperball2, was constructed to detect γ -rays emitted from the hypernuclei produced. Three hypernuclear γ -ray peaks were observed and assigned.

A laboratory simulation experiment was performed to observe the dynamical behavior of the earth’s magnetosphere, based upon the earthward electric field measurement in the magnetotail. The simulation was examined to satisfy the MHD scaling laws. The earthward electric field, Ex , is the signature of the current density based on j × B force in the tail, described by Podgorny (1978). The effect of the solar wind dynamic pressure to the earthward electric field, Ex , was investigated. The solar wind density was changed while the other parameters were kept almost constant. It is found that the Ex is modulated by the change in the solar wind dynamic pressure. The result also shows that the current continued to flow in the near earth region even after the solar wind had stopped. This result shows a similar resemblance to that of the particle confinement in the radiation belt of the real magnetosphere.

FLT3 is a member of receptor tyrosine kinases expressed in leukemia cells, as well as in hematopoietic stem cells. Recently, a somatic alteration of the FLT3 gene was found in acute myeloid leukemia, as an internal tandem duplication (FLT3/ITD) which caused elongation of the juxtamembrane (JM) domain of FLT3. Here we characterized the FLT3/ITD and investigated its clinical significance in acute promyelocytic leukemia (APL). Seventy-four newly diagnosed patients with APL, who were treated with the same protocol in a multi-institutional study, were studied for the FLT3/ITD. Genomic and message sequences of the FLT3 gene were amplified by means of polymerase chain reaction (PCR), and elongated PCR products were sequenced. Fifteen patients (20.3%) had FLT3/ITD, all of which were transcribed in frame. Location of the duplicated fragments (six to 30 amino acids) varied from patient to patient. However, they always contained either Y591 or Y599, but the tyrosine kinase domain was not significantly affected. This finding implied that signal transduction of FLT3 is amplified by the duplication. Clinically, the presence of FLT3/ITD was related to high peripheral white blood cell counts as well as peripheral leukemia cell counts (P < 0.0001), high LDH level (P = 0.04), and low fibrinogen concentration (P = 0.04). These data suggest that FLT3/ITD plays a significant role in progression of APL.

Cross section measurements of the exclusive p(e,e'K+)Lambda,Sigma^0 electroproduction reactions have been performed at the Mainz Microtron MAMI in the A1 spectrometer facility using for the first time the Kaos spectrometer for kaon detection. These processes were studied in a kinematical region not covered by any previous experiment. The nucleon was probed in its third resonance region with virtual photons of low four-momenta, Q^2= 0.030-0.055 (GeV/c)^2. The MAMI data indicate a smooth transition in Q^2 from photoproduction to electroproduction cross sections. Comparison with predictions of effective Lagrangian models based on the isobar approach reveal that strong longitudinal couplings of the virtual photon to the N* resonances can be excluded from these models., Comment: 16 pages, 7 figures

Hemorrhagic cystitis (HC) is a major cause of morbidity after allogeneic bone marrow transplantation (BMT). Many therapies have been investigated to prevent or treat HC, but effective treatment for HC is still limited. While the efficacy of hyperbaric oxygen therapy has been established for HC due to chemotherapy and/or radiation therapy, its role in HC occurring after allogeneic BMT has yet to be defined. We report two cases of life-threatening late-onset HC after allogeneic BMT in children, which resolved after treatment with hyperbaric oxygen.

We suggest a simple mixing model for the G(1440) and η′(1440) withJpc = 0-+. It is shown that the data for the radiative decays of J/Ψ and π+p → ηπ+π-n reaction can be explained well by the model.

The process of\(K^ - + d \to \mathfrak{N} + \mathfrak{N} + K\) is investigated from the kinematical point of view under the assumption that there exists an excited state Σ* for the\(K^ - - \mathfrak{N}\) system. It is pointed out that the reaction K−+d→n+n+K0 in the low energy region turns out to be forbidden owing to the Pauli principle in addition to the conservation laws of the total angular momentum and parity. Moreover the parity of Σ* is discussed on the basis of the character for angular distribution of K-meson.

The forward scattering amplitudeM(ω) (real partD(ω), imaginary partA(ω)) in pion nucleon scattering is discussed when the acausal spread of the current commutator over the space-like interval is very small. If the acausal smearing is so small as to justify the treating of its effect as a perturbation, the errors of the dispersion relations are proved to be energy independent in the first order approximation. Hence, there would be no guarantee of affecting micro-causality even if the dispersion relations written, as they are, in a form of subtractionD(ω) —D(μ) could be in agreement with the experiment.

The experimental results for K−-p collision obtained byGlasseret al. are analyzed in a phenomenological way. One of our conclusions is that the experimental results for K−-p scattering at low energy can be explained by taking account of the effects of absorption, even if the values of phase shifts are not so large. Moreover, whether the phenomenological analysis worked out byAscoliet al. is reasonable or not is discussed.

Proton Compton scattering at (600÷750) MeV is described in terms of the effects of possible resonancesS11 andP11 in addition to those of the well-establishedP23(1238) andD13(1518). The main results are the following: 1) The angular distribution for γ-p elastic scattering becomes larger in the forward than in the backward direction as the incident energy increases. 2) dσ/dΩ(90°) around 740 MeV can be described fairly well by the effect of theD13(1518). In scattering at (600÷675) MeV, on the other hand, contributions from theD13(1518) to dσ/dΩ(90°) are nearly equal to those from the other resonant states. 3) Polarization measurements on proton Compton scattering at (700÷740) MeV can give us important information concerning both the existence of theP11(1480) and the properties of theS11 resonance.

A simple analysis of the experimental results for photoproduction of pions at (250 ÷ 800) MeV is made and photon-proton scattering at these energies is described in terms of shadow scattering due, to photoproduction of pions. The total cross-sections for photon-proton scattering show the existence of a strong and broad resonance corresponding to the second resonance for photoproduction of pions at about 750 MeV. Since the resonance behavior is strongly reflected in photon-proton scattering, this process may be regarded as one of the most suitable reactions to study the character of the second resonance.

The effect of the nucleon structure is discussed correlating phenomenologically a variety of pion-nucleon phenomena with the nucleon core. In the high energy region, the various experimental evidence is interpreted in terms of nucleon structure. The main results are: 1) The optical radiusR of the proton estimated from the π−-p elastic scattering is nearly constant in the energy region (1÷5) GeV. 2) The effective collision parameter in the π−-p reaction shows the nearly constant value 0.8·1013 cm in the (1÷5) GeV region. 3) The mean energy of the mesons produced in the π+-p reaction in the energy range (1÷5) GeV indicates a picture of meson production as a shaking off of mesons from the nucleon core. 4) In the nucleon-nucleon collision in GeV order, the mean neergy of the produced mesons suggests a shaking off of the external meson cloud such as given by the isobar model. 5) A regularity of the reduced multi-plicity is discussed concerning the proton-antiproton annihilation star. In the low energy region, the well known failure of the meson theory on theS wave is to be ascribed to the internal effect of the nucleon structure (Appendix).

A model for the meson( pi )-nucleon interaction at about 2 Bev is used to calculate the effect of the meson(f/sup 0/). The process. There is a maximum in the interaction total cross section with excitation energy slightly above the threshold energy for pi + N yields f/sup 0/ + N production, and the I = 1/2 state in the ( pi --N) system is responsible for this maximum because the isotropic spin of the meson(f/sup 0/) is zero. On the basis of the model. the total angular momentum and parity states responsible for the maximum of the total cross section ( pi /sup -/-p) at 2 Bev are discussed. The angular distributions of the meson(f/sup 0/) are also given. (C.E.S.)

The shrinking diffraction peak in p-p scattering and the non-shrinking diffraction peak in pi /sup plus or minus /-p scattering are discussed with respect to the validity of the Regge pole concept and possible new Regge trajectories that are not as yet established. Predictions are made concerning the diffraction peak for K/sup plus or minus /-p scattering. (C.E.S.)

π−-p charge exchange scattering near 2 GeV/c is described in terms of the amplitudes due to ρ-exchange and one-nucleon-exchange in addition to the resonant amplitude. It is shown that the experimental results can be explained fairly well by such an approach. Since the resonant amplitude has a large effect on the behaviour of dσ/dΩ in the backward direction, measurements of backward scattering near 2 GeV/c give us important information concerning the existence of a new resonant state whose mass is nearly equal to 2200 MeV. The polarization of recoil nucleons is predicted with the same model. Moreover the interference between the one-meson-exchange amplitude and the one-nucleon-exchange amplitude is discussed by paying attention to its effect on the behaviour of dσ/dΩ at high energy.

Backward π+-p elastic scattering at (1.7÷7.8) GeV/c is described in terms of the resonant amplitude and the nucleon-exchange amplitude. It is shown that experimental results for dσ/dΩ in the backward direction can be fairly well explained without the Regge-pole theory. For the polarization of recoil protons in backward π+-p scattering at (2÷4) GeV/c, there is a large difference between our results and the predictions obtained by adding the resonant amplitude and Regge exchange amplitude. Polarization measurements give us important information concerning the theory by which high-energy phenomena can be well described.

The experimental results of the proton-proton collisions at 1.5 GeV and 2.75 GeV by Fowleret al. are analysed in a phenomenological way. It is found then that the partial waves ofl = 2/5 and Z= 2 / 7 are mainly responsible for the pion production at1.5 GeV and 2.75 GeV respectively. Further, from our analysis in such an energy region it is shown that the effective size of the proton is nearly constant ((0.6/0.7).10-3cm).

A possible test of the global symmetry proposed independently by Gell- Mann. Schwinger, and Tiomno is discussed. The discussion is confined to the case of final three-body reactions where the conservation of energy and angular momentum appear less restrictive for a pair among the final three particles.