The large N limit of M2-branes on Lens spaces

We study the matrix model for N M2-branes wrapping a Lens space L(p,1) = S^3/Z_p. This arises from localization of the partition function of the ABJM theory, and has some novel features compared with the case of a three-sphere, including a sum over flat connections and a potential that depends non-trivially on p. We study the matrix model both numerically and analytically in the large N limit, finding that a certain family of p flat connections give an equal dominant contribution. At large N we find the same eigenvalue distribution for all p, and show that the free energy is simply 1/p times the free energy on a three-sphere, in agreement with gravity dual expectations.Comment: 28 pages, 4 figure

Numerically improved computational scheme for the optical conductivity tensor in layered systems

The contour integration technique applied to calculate the optical conductivity tensor at finite temperatures in the case of layered systems within the framework of the spin-polarized relativistic screened Korringa-Kohn-Rostoker band structure method is improved from the computational point of view by applying the Gauss-Konrod quadrature for the integrals along the different parts of the contour and by designing a cumulative special points scheme for two-dimensional Brillouin zone integrals corresponding to cubic systems.Comment: 17 pages, LaTeX + 4 figures (Encapsulated PostScript), submitted to J. Phys.: Condensed Matter (19 Sept. 2000

Modalites de consommation et valeur nutritionnelle des legumineuses alimentaires au Burkina Faso

Au Burkina Faso les légumineuses constituent une source importante de nutriments pour les populations. La présente étude a eu pour objectif de déterminer la valeur nutritionnelle et la place des légumineuses dans le régime alimentaire des ménages à Ouagadougou, Kaya, Lebda et Nobéré. La méthodologie a consisté en une enquête de consommation alimentaire auprès de 325 ménages et à déterminer les teneurs en macronutriments et en minéraux fer, zinc et calcium de six (6) variétés de légumineuses. Il en résulte que les principales légumineuses consommées dans les ménages sont l’arachide (Arachis hypogea L.), le niébé (Vigna unguiculata L.), le voandzou (Vigna subterranea L.), le soja (Glycine max L.) et le zamnè (Acacia macrostachya R.). L’arachide, le niébé et le voandzou sont consommées plus 2 à 4 fois dans le mois par l’ensemble des ménages sous forme de mets au sein des ménages tandis que le soja et le zamnè sont consommés hors ménage. A l’exception du voandzou qui est consommé au déjeuner par 38,30% des ménages à Ouagadougou, 60% à Kaya, 66,67% à Lebda et 43,18% à Nobéré, les autres légumineuses sont consommées à tout moment de la journée par plus de 80 % des ménages enquêtés. Les légumineuses niébé, voandzou et zamnè sont consommées sous forme de ragout et de plats associés à des céréales respectivement par 99%, 93% et 76%. L’arachide et le soja sont utilisés comme des ingrédients ou comme des collations. Les légumineuses ont des teneurs importantes en protéines, 35,76%, 31,04%, 27,29%, 22,55% et 20,38% respectivement pour le zamnè, le soja, l’arachide, le niébé et le voandzou. Les teneurs en lipides sont faibles et contribuent à moins de 7% à la valeur énergétique. Le niébé et le voandzou ont des teneurs en carbohydrates élevées, près de 60%. Les teneurs en fer des légumineuses varient de 1,77 mg/100g (voandzou) à 6,50 mg/100g (soja). Celles en zinc varient de 5,34 mg/100 g (zamnè) à 4,33 mg/100g (soja). Le soja et le zamnè ont d’importantes teneurs en calcium, respectivement 57,42 mg/100g et 68,40 mg/100g. Du fait de leur valeur nutritionnelle intéressante en micronutriments ces deux légumineuses nécessitent une attention particulière pour l’enrichissement des produits locaux. La diversification des produits issus de ces légumineuses ainsi que celle des méthodes de consommation au sein des ménages permettront un meilleur profilage de leur bénéfice nutritionnel auprès des populations.Mots clés: Légumineuses, importance, consommation, ménages, nutriments, urbain, rural, Burkina Fas

Low Energy Pion-Hyperon Interaction

We study the low energy pion-hyperon interaction considering effective non-linear chiral invariant Lagrangians including pions, rho mesons, hyperons and corresponding resonances. Then we calculate the S- and P-wave phase-shifts, total cross sections, angular distributions and polarizations for the momentum in the center-of-mass frame up to k=400 MeV. With these results we discuss the CP violation in the csi-> pi-lambda and omega-> pi-csi weak decays.Comment: 10 pages, 10 figure

Torqued fireballs in relativistic heavy-ion collisions

We show that the fluctuations in the wounded-nucleon model of the initial stage of relativistic heavy-ion collisions, together with the natural assumption that the forward (backward) moving wounded nucleons emit particles preferably in the forward (backward) direction, lead to an event-by-event torqued fireball. The principal axes associated with the transverse shape are rotated in the forward region in the opposite direction than in the backward region. On the average, the standard deviation of the relative torque angle between the forward and backward rapidity regions is about 20deg for the central and 10deg for the mid-peripheral collisions. The hydrodynamic expansion of a torqued fireball leads to a torqued collective flow, yielding, in turn, torqued principal axes of the transverse-momentum distributions at different rapidities. We propose experimental measures, based on cumulants involving particles in different rapidity regions, which should allow for a quantitative determination of the effect from the data. To estimate the non-flow contributions from resonance decays we run Monte Carlo simulations with THERMINATOR. If the event-by-event torque effect is found in the data, it will support the assumptions concerning the fluctuations in the early stage of the fireball formation, as well as the hypothesis of the asymmetric rapidity shape of the emission functions of the moving sources in the nucleus-nucleus collisions.Comment: Grant reference adde

Using white noise to gate organic transistors for dynamic monitoring of cultured cell layers.

Impedance sensing of biological systems allows for monitoring of cell and tissue properties, including cell-substrate attachment, layer confluence, and the "tightness" of an epithelial tissue. These properties are critical for electrical detection of tissue health and viability in applications such as toxicological screening. Organic transistors based on conducting polymers offer a promising route to efficiently transduce ionic currents to attain high quality impedance spectra, but collection of complete impedance spectra can be time consuming (minutes). By applying uniform white noise at the gate of an organic electrochemical transistor (OECT), and measuring the resulting current noise, we are able to dynamically monitor the impedance and thus integrity of cultured epithelial monolayers. We show that noise sourcing can be used to track rapid monolayer disruption due to compounds which interfere with dynamic polymerization events crucial for maintaining cytoskeletal integrity, and to resolve sub-second alterations to the monolayer integrity

Status Report of LNS Accelerator Complex in 2002(IV. Status Report of LNS Accelerator Complex in 2002)

Operation status of an electron accelerator complex at Laboratory of Nuclear Science, Tohoku University is reported. After a completion of a new building containing an experimental vault, the inspection for the radiation safety was done in the beginning of October, 2003, so that most of user machine time was consumed in the latter half of the fiscal year 2002

The Omega Deformation From String and M-Theory

We present a string theory construction of Omega-deformed four-dimensional gauge theories with generic values of \epsilon_1 and \epsilon_2. Our solution gives an explicit description of the geometry in the core of Nekrasov and Witten's realization of the instanton partition function, far from the asymptotic region of their background. This construction lifts naturally to M-theory and corresponds to an M5-brane wrapped on a Riemann surface with a selfdual flux. Via a 9-11 flip, we finally reinterpret the Omega deformation in terms of non-commutative geometry. Our solution generates all modified couplings of the \Omega-deformed gauge theory, and also yields a geometric origin for the quantum spectral curve of the associated quantum integrable system.Comment: LaTeX, 35 pages, 1 figure. Appendix on couplings of hypermultiplets in N=4 SYM adde