TACA

The airline industry is energy intensive, has high fixed costs and its demand is very sensitive to the economic cycle. After the industry worldwide undergoes deregulation, starting with the United States in 1978, two distinct business models develop. Traditional carriers operate hub and spoke networks, offer onboard service and engage in price discrimination, whereas low cost carriers operate point to point, charge for all services and have simple tariffs. TACA begins operations in Central America in 1931 and, by 1943, has a footprint that extends from the United States to Argentina. In 1998–2001 TACA faces increased competition and a significant market downturn. In 2004 TACA CEO Roberto Kriete launches Centroamérica Fácil to stimulate air traffic in the airline\u27s base countries

Toll-like receptor (TLR) 2 and TLR4 gene expression in canine heart

Toll-like receptors (TLRs) are archetypal pattern recognition receptors of immediate importance for an efficacious innate immune response. TLRs exhibit marked differential tissue activity and their levels within a discrete cell type can be highly dynamic. Of 13 known mammalian paralogues, three TLRs have been identified in the dog. Although cardiac TLR expression has been reported in other species, this study is the first to present evidence that these innate immune receptors are expressed in the canine heart. Heart tissue samples from all four chambers were collected from healthy dogs immediately after euthanasia and stored at -80°C until analysis. Total RNA was extracted with TRI Regent. Specific primers were designed for amplification of canine TLR2 and TLR4 based on previously reported sequences for these genes. Reverse transcription was performed with M-MLV reverse transcriptase. PCR amplification was performed and PCR products analyzed by agarose gel electrophoresis. Bands were excised from the gel and the DNA isolated and cloned using the TA Cloning® Kit. The correct sequence for each product was verified by nucleotide sequencing. TLR4 expression was detected in the left ventricle and right atrium; TLR2 was detectable at low levels in the right atrium only. Identity of the RT-PCR products was confirmed by sequencing. Our findings show that at least two TLR paralogues- namely TLR2 and TLR4 - are expressed in the canine heart. Additional studies are warranted to determine these immune receptors' potential implication in the development of naturally occurring heart disease in the dog

Banco Solidario S.A.: The Recovery Strategy, 2000–2004

Five years passed since, in April, 2000, Kurt Koenigsfest took over as the Chief Executive Officer at Banco Solidario S.A. (BancoSol), in La Paz, Bolivia. BancoSol had become the top Latin American bank specializing in providing microbusiness services. Since its beginning in 1992, BancoSol achieved excellent results and became an international reference in the microcredit area. In mid-2000, external and internal factors caused its performance to deteriorate. Kurt and his management team set and implemented a strategy that led the bank to be rated as the best financial institution in the Bolivian financial system in 2004. The time had come to plan for the future; the management team has to establish BancoSol\u27s primary lines of action for the next three years

N=2 SUGRA BPS Multi-center solutions, quadratic prepotentials and Freudenthal transformations

We present a detailed description of N=2 stationary BPS multicenter black hole solutions for quadratic prepotentials with an arbitrary number of centers and scalar fields making a systematic use of the algebraic properties of the matrix of second derivatives of the prepotential, $\mathcal{S}$, which in this case is a scalar-independent matrix. In particular we obtain bounds on the physical parameter of the multicenter solution such as horizon areas and ADM mass. We discuss the possibility and convenience of setting up a basis of the symplectic vector space built from charge eigenvectors of the \ssigma, the set of vectors (\Ppm q_a) with \Ppm \ssigma-eigenspace proyectors. The anti-involution matrix $\mathcal{S}$ can be understood as a Freudenthal duality \tilde{x}=\ssigma x. We show that this duality can be generalized to "Freudenthal transformations" x\to \lambda\exp(\theta \ssigma) x= a x+b\tilde{x} under which the horizon area, ADM mass and intercenter distances scale up leaving constant the fix point scalars. In the special case $\lambda=1$, "\ssigma-rotations", the transformations leave invariant the solution. The standard Freudental duality can be written as \tilde x= \exp(\pi/2 \ssigma) x . We argue that these generalized transformations leave also invariant the general stringy extremal quartic form $\Delta_4$, $\Delta_4(x)= \Delta_4(\cos\theta x+\sin\theta\tilde{x})$.Comment: Latex 27 pages (11pt). Some modifications introduced. Minor misprints corrected. References adde

All gaugings and stable de Sitter in D=7 half-maximal supergravity

We study the general formulation of gauged supergravity in seven dimensions with sixteen supercharges keeping duality covariance by means of the embedding tensor formalism. We first classify all inequivalent duality orbits of consistent deformations. Secondly, we analyse the complete set of critical points in a systematic way. Interestingly, we find the first examples of stable de Sitter solutions within a theory with such a large amount of supersymmetry.Comment: 25 pages, 1 figure, 7 table

A New Approach to Non-Abelian Hydrodynamics

We present a new approach to describe hydrodynamics carrying non-Abelian macroscopic degrees of freedom. Based on the Kaluza-Klein compactification of a higher-dimensional neutral dissipative fluid on a group manifold, we obtain a d=4 colored dissipative fluid coupled to Yang-Mills gauge field. We calculate the transport coefficients of the new fluid, which show the non-Abelian character of the gauge group. In particular, we obtain group-valued terms in the gradient expansions and response quantities such as the conductivity matrix and the chemical potentials. While using SU(2) for simplicity, this approach is applicable to any gauge group. Resulting a robust description of non-Abelian hydrodynamics, we discuss some links between this system and quark-gluon plasma and fluid/gravity duality.Comment: 41 pages (31 + appendices), 1 figure. V2: Minor modifications, some typos fixed and references adde

Laboratory and numerical investigations of soil retention curves

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