The phase shift of line solitons for the KP-II equation

The KP-II equation was derived by [B. B. Kadomtsev and V. I. Petviashvili,Sov. Phys. Dokl. vol.15 (1970), 539-541] to explain stability of line solitary waves of shallow water. Stability of line solitons has been proved by [T. Mizumachi, Mem. of vol. 238 (2015), no.1125] and [T. Mizumachi, Proc. Roy. Soc. Edinburgh Sect. A. vol.148 (2018), 149--198]. It turns out the local phase shift of modulating line solitons are not uniform in the transverse direction. In this paper, we obtain the $L^\infty$-bound for the local phase shift of modulating line solitons for polynomially localized perturbations

Numerical study of oscillatory regimes in the Kadomtsev-Petviashvili equation

The aim of this paper is the accurate numerical study of the KP equation. In particular we are concerned with the small dispersion limit of this model, where no comprehensive analytical description exists so far. To this end we first study a similar highly oscillatory regime for asymptotically small solutions, which can be described via the Davey-Stewartson system. In a second step we investigate numerically the small dispersion limit of the KP model in the case of large amplitudes. Similarities and differences to the much better studied Korteweg-de Vries situation are discussed as well as the dependence of the limit on the additional transverse coordinate.Comment: 39 pages, 36 figures (high resolution figures at http://www.mis.mpg.de/preprints/index.html

Using viral vectors as gene transfer tools (Cell Biology and Toxicology Special Issue: ETCS-UK 1 day meeting on genetic manipulation of cells)

In recent years, the development of powerful viral gene transfer techniques has greatly facilitated the study of gene function. This review summarises some of the viral delivery systems routinely used to mediate gene transfer into cell lines, primary cell cultures and in whole animal models. The systems described were originally discussed at a 1-day European Tissue Culture Society (ETCS-UK) workshop that was held at University College London on 1st April 2009. Recombinant-deficient viral vectors (viruses that are no longer able to replicate) are used to transduce dividing and post-mitotic cells, and they have been optimised to mediate regulatable, powerful, long-term and cell-specific expression. Hence, viral systems have become very widely used, especially in the field of neurobiology. This review introduces the main categories of viral vectors, focusing on their initial development and highlighting modifications and improvements made since their introduction. In particular, the use of specific promoters to restrict expression, translational enhancers and regulatory elements to boost expression from a single virion and the development of regulatable systems is described

Chambre d'ionisation multicellulaire pour l'étude du faisceau de protons de 150 MeV du synchrocyclotron d'Orsay

A multicellular ionization chamber is described which is used for beam adjustments of the Orsay synchrocyclotron. This chamber consist of some thirty cells obtained by metallizing a mylar foil. It can be used in an intensity range from 106 to 1010 protons/cm2/s.Nous décrivons une chambre d'ionisation multi-cellulaire qui est utilisée pour effectuer les réglages de faisceau du synchrocyclotron d'Orsay. Cette chambre se compose d'une trentaine de cellules obtenues par métallisation d'une feuille de mylar. Elle est utilisable dans une plage d'intensité allant de 106 à 1010 protons/cm2/s

Étude des réactions pp'γ provoquées par des protons de 155 Mev. Cas de la résonance géante

In order to hâve more information about the excitation of the giant resonance by inelastic scattering of protons, we have searched the γ rays associated with this excitation. The ratio dσpp'γ/dΩ / dσ pp'/dΩ is given for scattering angles for protons of 10° and 25° for a 12C target, and 25° for an 16O target.Les protons énergiques excitent les noyaux à la résonance géante. Pour tenter de préciser ce processus, nous avons recherché les photons d'environ 20 MeV associés aux protons p' diffusés inélastiquement qui excitent la résonance géante. On donne le rapport σ(pp'γ) /σ(pp') pour les noyaux 12C et 16O pour des angles de diffusion des protons de 10° et 25° pour le premier cas et 10° pour le second

Étude des réactions pp'γ à 151 MeV. Cas du niveau de 15,1 Mev de 12C

Excitation of the 15.1 MeV level of 12C by scattering of 151 MeV protons has been studied by coincidence between protons and de-excitation γ rays. We give the angular distribution of protons in coincidence with γ rays in the recoil nucleus direction, the correlation between protons scattered at 8° and γ rays, and the inelastic scattering cross-section at 8°.L'excitation du niveau de 15,1 MeV de 12C par les protons de 151 MeV, a été étudiée par coïncidences entre les protons diffusés et les protons de désexcitation. On donne la distribution angulaire des protons en coïncidence avec les protons émis dans le plan de diffusion à 70° du faisceau, et la valeur absolue de la section efficace différentielle de diffusion des protons à 8°. On donne également l'anisotropie de la corrélation angulaire p'γ à 8° dans le plan de diffusion

Étude des niveaux fortement excités du 12C par la polarisation des protons diffusés inélastiquement

In general agreement with theory, protons inelastically scattered in the excitation of levels other than ΔT = 0 favoured parity, show a very low polarization. Polarization of 150 MeV protons from excited states of high energy in C12 gives information on the nature of these levels.On compare, dans le cas de niveaux bien connus, les valeurs expérimentales de polarisation à celles prévues dans l'approximation d'impulsion. En accord général avec la théorie, à l'exception des niveaux à parité favorisée avec Δ T = 0, les polarisations sont faibles. Les niveaux pour lesquels les polarisations sont élevées peuvent donc être considérés pour 12C comme T = 0 parité favorisée