Variations on the warped deformed conifold

The warped deformed conifold background of type IIB theory is dual to the cascading SU(M(p+1))×SU(Mp) gauge theory. We show that this background realizes the (super-)Goldstone mechanism where the U(1) baryon number symmetry is broken by expectation values of baryonic operators. The resulting massless pseudo-scalar and scalar glueballs are identified in the supergravity spectrum. A D-string is then dual to a global string in the gauge theory. Upon compactification, the Goldstone mechanism turns into the Higgs mechanism, and the global strings turn into ANO strings. To cite this article: S.S. Gubser et al., C. R. Physique 5 (2004).

Résumé

La configuration de fond pour la théorie de type IIB donnée par le conifold voilé déformé est duale à la cascade de théorie de jauge SU(M(p+1))×SU(Mp). Nous montrons que cette configuration donne une réalisation du mécanisme de (super-)Goldstone où la symètrie baryonique U(1) est brisée par la valeur moyenne dans le vide des opérateurs baryoniques. Les boules de glue pseudo-scalaires et scalaires de masse nulle résultantes sont identifiées dans le spectre de supegravité. Une D-corde est alors duale à une corde globale dans la théorie de jauge. Après compactification, le mécanisme de Goldstone devient un mécanisme de Higgs, et une corde globale devient une corde ANO. Pour citer cet article : S.S. Gubser et al., C. R. Physique 5 (2004).     

Higher spin gauge theories in any dimension

Some general properties of higher spin gauge theories are summarized, with the emphasize on the nonlinear theories in any dimension. To cite this article: M.A. Vasiliev, C. R. Physique 5 (2004).

Résumé

Des propriétés générales des théories de jauge de grands spins sont présentées, en insistant particulièrement sur les théories non-linéaires en dimensions diverses. Pour citer cet article : M.A. Vasiliev, C. R. Physique 5 (2004).     

A Novel Stereoselective Synthesis of <Emphasis Type="Italic">cis</Emphasis>-Configured Erythrinane and Erythrinane Type Analogues

Summary. N-Alkylation of certain angularly substituted heterocycles by C₂- and C₃-units provided appropriate precursors to construct stereoselectively the erythrinanone and several erythrinanone type analogues by intramolecular Friedel-Crafts acylation. The resulting aromatic ketones were catalytically reduced affording the corresponding parent frameworks including the hitherto unknown tetracyclus A-norschelhammerane. On the other hand, the stereoselective reduction of the carbonyl moiety offered a convenient approach to 11-hydroxylated erythrinanes with the natural occurring -configuration. The structures and the stereochemistry of the target compounds were proved by NMR spectroscopy.Part of PhD thesis, LMU München, D     

Simultaneous determination of <Emphasis Type="SmallCaps">L</Emphasis>-arginine and its mono- and dimethylated metabolites in human plasma by high-performance liquid chromatography–mass spectrometry

A simple, fast, sensitive, and reproducible isocratic liquid chromatography–mass spectrometry (LC-MS) method coupled with an atmospheric pressure chemical ionization (APCI) interface for simultaneous separation and determination of L-arginine (ARG) and its methylated metabolites, N-monomethyl-L-arginine (MMA), N^G,N^G-dimethylarginine (asymmetric dimethyl arginine, ADMA), and N^G,N^G-dimethylarginine (symmetric dimethyl arginine, SDMA), in human plasma is presented. Sample pretreatment is not required other than deproteinization with 5-sulfosalicylic acid (5-SSA). Satisfactory chromatographic separation was achieved on a 2.0×150-mm Shimadzu VP-ODS column by using a mobile phase consisting of water/acetonitrile (90/10, v/v) containing 0.5% trifluoroacetic acid (TFA). Positive selective ion monitoring (SIM) mode was chosen for quantification of each analyte. The positively protonated molecular ions [M+H]⁺ of ARG, MMA, ADMA, and SDMA were monitored at m/z 175, 189, 203, and 203, respectively. L-Homoarginine was used as the internal standard (IS) for the assay. The limits of quantification (LOQs) were found to be 1.0 mol L^–1 for ARG, and 0.2 mol L^–1 for MMA, ADMA, and SDMA. The inter-assay precision and accuracy were in the range of 1.8–4.9% and –3.0–5.0%, respectively. The intra-assay precision and accuracy were in the order of 1.7–4.6 and –2.6–4.0%, respectively. The recoveries were between 90.0 and 106.6%. The levels of ARG, MMA, ADMA, and SDMA in human plasma were also determined using the developed method.     

Beam-injection flame furnace AAS: comparison of different nozzle types for beam generation and application of sub-critical liquid carbon dioxide as carrier and gas pressure pump

In beam injection flame furnace AAS (BIFF-AAS) the sample is introduced as a free-flying high-speed liquid beam into an AAS flame-heated nickel tube, resulting in a considerable improvement in the power of detection. For optimization of beam generation different nozzle types (smooth jet nozzles, turbulent working nozzles) have been compared at different pressures. It was found that the type of the nozzle hardly influences the analytical signal. However, the flow rates resulting from the different inner diameters of the nozzles and the applied pressures led to drastic changes in the analytical signal. For these investigations a recently developed 0.6 MPa (84 psig) diaphragm pump system was used. Furthermore, for the first time ever sub-critical liquid carbon dioxide has been used simultaneously as a liquid gas-pressure pump, as carrier in a flow-injection system (FIA), and for the beam generation. Transport of the carrier takes place as a result of the head pressure (6 MPa) of the liquid CO₂ in the gas cylinder. For volatile elements (e.g. Cd, Hg, Pb, and Tl) detection limits between 0.2 µg L^–1 (Cd) and 28 µg L^–1 (Hg) were found, the standard deviation was from 0.6% to 3.2% depending on the element, concentration, and sample volume used. The use of liquid CO₂ as a carrier in FIA systems opens up new possibilities for online sample pretreatment and trace preconcentration.     

Real <Emphasis Type="Italic">AW</Emphasis><Superscript>*</Superscript>-Algebras of type I

Let R be a real AW ^*-algebra, and suppose that its complexification M = R + iR is also a (complex) AW ^*-algebra. We prove that R is of type I if and only if so is M.Translated from Funktsionalnyi Analiz i Ego Prilozheniya, Vol. 38, No. 4, pp. 79–81, 2004Original Russian Text Copyright © by Sh. A. Ayupov     

Gauge-Invariant Regularization of Quantum Field Theory on the Light Front

We briefly describe problems of the Hamiltonian approach for quantizing gauge fields on the light front for space–time bounded by the inequality |x ^–|L with periodic boundary conditions in the variable x ^– imposed on all fields (the DLCQ method). With these restrictions, we consider the gauge-invariant ultraviolet regularization by passing to a lattice in transverse coordinates. We remove the remaining ultraviolet divergences in the longitudinal momentum p _– by imposing a gauge-invariant finite-mode regularization. It turns out that the canonical formalism on the light front with such a regularization imposed does not contain the usual most complicated second-class constraints between zero and nonzero modes of fields. The described scheme can be used both to regularize the standard gauge theory and to provide a gauge-invariant formulation of effective low-energy models on the light front. Because the manifest Lorentz invariance is broken in our formalism, the vacuum state is poorly defined. We discuss this problem, in particular, in relation to the problem of passing to the continuous space limit.     

Infrared Variables for the SU(3) Yang–Mills Field

We generalize the self-dual parameterization of the SU(2) Yang–Mills field proposed by Niemi and Faddeev for describing the infrared limit of the theory to the case of the gauge group SU(3). We demonstrate that the duality property intrinsic to the SU(2) gauge field cannot be transferred automatically to the higher-rank group case. We interpret the algebraic structures appearing in the Lagrangian for the new compact variables in terms of the group products SU(2)³.     

Weighted weak type estimates for commutators of the Marcinkiewicz integrals

In this paper the authors give the weighted weak L logL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities for the Marcinkiewicz integral and its commutators with different weight functions are also discussed.     

Optimal Control Problem Associated with Jump Processes

An optimal portfolio/control problem is considered for a two-dimen\-sional model in finance. A pair consisting of the wealth process and cumulutative consumption process driven by a geometric Lévy process is controlled by adapted processes. The value function appears and turns out to be a viscosity solution to some integro-differential equation, by using the Bellman principle.