Entanglement Entropy of the Low-Lying Excited States and Critical Properties of an Exactly Solvable Two-Leg Spin Ladder with Three-Spin Interactions

In this work, we investigate an exactly solvable two-leg spin ladder with three-spin interactions. We obtain analytically the finite-size corrections of the low-lying energies and determine the central charge as well as the scaling dimensions. The model considered in this work has the same universality class of critical behavior of the XX chain with central charge c=1. By using the correlation matrix method, we also study the finite-size corrections of the Renyi entropy of the ground state and of the excited states. Our results are in agreement with the predictions of the conformal field theory.Comment: 10 pages, 6 figures, 2 table

A Historical Study of the Medical Corps of the Continental Army

The purpose of this thesis is to trace the establishment and development of the Medical Corps of the Continental Army, through its Directors General, during the Revolutionary War. It will review the administration of each of the four Directors General and will try to indicate the degree of efficiency or incompetence of the administration of each. The main objective of this thesis will be to relate the story of the Medical Corps during the Revolutionary War and determine whether this organization was efficient and gave proper and adequate medical care to the sick and wounded officers and men of the Continental Army and Navy and whether this medical care was efficient and proper as that given to the English and German troops by their own medical systems

REAHs and REAH-Like Lesions: Underdiagnosed lesions Often Misconfused with Nasal Polyps

REAH is the eponym for respiratory epithelial adenomatoid hamartoma. The disease is under diagnosed. It is clearly a disease in the olfactory cleft. It is characterized by a polypoid process located in the olfactory cleft which does not evolve in inverted papilloma or malignancy set at 10–15 cm. The lesion can be isolated in one or both olfactory cleft. It can be asymptomatic or can cause nasal obstruction and impairment of smell. More commonly the lesions, often multiple, are associated to the recurrence of the nasal polyposis. They can contribute to the development of loss of smell, nasal obstruction or even the blockage of the frontal recesses. The definitive diagnostic is based upon the histologic examination. Surgery is the treatment. In case of isolated lesion, complete excision without complete ethmoidectomy is the option. In case of lesions embedded in a recurrent massive polyposis, a complete exenteration of the olfactory clefts associated to a revision of full house ethmoidectomy and even a Draf III must be considered

Transcripcional, functional and virulence analysis of a Pseudomonas Savastanoi pv. savastanoi genomic region shared with other pathogens of woody hosts

Comunicación al XVI congreso de la Sociedad Internacional de Interacciones moleculares Planta-PatógenoThe genome of the olive tree pathogen Pseudomonas savastanoi pv. savastanoi (Psv) NCPPB3335 (58.1% G+C) encodes a region of about 15 kb, named VR8 (60.4% G+C), which is absent in all sequenced Pseudomonas syringae strains infecting herbaceous plants, but shared with P. syringae pathovars infecting woody hosts. RT-PCR analysis of the VR8 genes revealed the existence of 4 possible operons, of which the antABC and catBCA operons are involved in the degradation of anthranilate and catechol, respectively. The antABC cluster is homologous to the anthranilate degradation genes found on plasmid pCAR1 of Pseudomonas resinovorans. The other two operons, here called AER-1901/2/3 and AER-1904/5, also show homology to genes related with the degradation of aromatic compounds. RT-qPCR and ß-galactosidase assays of a LacZ fusions showed that both anthranilate and 6-chloro-antrhanilate induce the antABC operon. In addition, anthranilate also induces the catB gene. To analyse the role in virulence of the VR8, we constructed several knockout mutants of this region. The volume of the knots induced in non lignified olive plants by Psv mutants affected in the antABC or catBCA operons resulted to be similar to those induced by the wild-type strain. However, the severity of the symptoms generated by the antABC mutant in lignified olive plants was significantly lower than that induced by the wildtype strain, suggesting a possible role of this operon in the degradation of lignin-derived compounds. At present, we are analysing the role in virulence of the other three operons and of the AER-1900 gene (a putative aerotaxis receptor).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Yield, quality, alternate bearing and long-term yield index in pecan, as a response to mineral and organic nutrition

The pecan nut is produced in 57 countries in the world. Alternate bearing is one of the main biological problems that affect pecan cultivation. Mineral and organic fertilization is a good strategy to maintain and increase pecan nut production. In this study, several mineral and organic doses of fertilization were tested using a factorial arrangement 56 bounded to 25 treatments was used in structure Taguchi L25: nitrogen (N) 0 - 240 kg ha-1, phosphate (P2O5) 0 - 120 kg ha-1, potassium (K2O) 0 - 100 kg ha-1, calcium (CaO) 0 - 400 kg ha-1, liquid humus 0 - 3600 L ha-1 and solid humus 0 - 8000 kg ha-1. The study was carried out in Aldama city, Chihuahua (Mexico). An average yield of 2.4 t ha-1 was obtained, 157 nuts per kilogram and 58.9% of edible nut. The average alternate bearing intensity was 31.58%, and the long-term yield index (IRLP) was 9.59%. It is concluded that the factors whit the greatest impact on the analyzed variables were N and P2O5. In addition, it was found these mineral and organic fertilization systems help to reduce alternate bearing in pecan and simultaneously improve production and long-term productivity index. Optimal fertilization doses were defined: 181.4 kg ha-1 of N, 93.5 kg ha-1 of P2O5 and 3287.2 L ha-1 of liquid humus. Finally, the mineral fertilization complemented with organic fertilization is considered a good fertilization strategy for pecan trees, to increase production and with lower environmental impact

A strongly-coupled model for flexible rotors

International audienceA fluid-structure model describing the equilibrium state of a flexible blade rotor with its own wake is derived for various external axial flow conditions. The model is based on three building blocks. The two-dimensional lifting-line theory is first used to compute the local aerodynamic loads and the blade circulation profile. The blade deformation is then obtained by solving the nonlinear equations for bending and twisting angles deduced from a one-dimensional beam model. Finally, the wake is obtained using a Joukowski model. In this wake model, the wake of each blade is modeled by two small-core-size counter-rotating vortices emitted from the rotor axis and blade tip. The velocity field induced by these vortices is computed using the Biot-Savart law. We show that, in the rotor frame, we can obtain a stationary vortex structure for almost any vertical flight regimes. This wake solution can then be used to compute the induced velocity in the rotor plane and apply the two-dimensional lifting-line theory again. By iterating a few times this loop, we converge toward a nonlinear solution of the problem for which the aerodynamics loads, blade deformation and wake structure are compatible. As illustration, this newly-developed model is applied to two rotors. We analyze the effects of the external wind conditions, geometry and material properties of the blades on the blade deformation and wake characteristics. We show that we can describe slow descending regimes for which the classical momentum theory does not apply

Exploring AdS Waves Via Nonminimal Coupling

We consider nonminimally coupled scalar fields to explore the Siklos spacetimes in three dimensions. Their interpretation as exact gravitational waves propagating on AdS restrict the source to behave as a pure radiation field. We show that the related pure radiation constraints single out a unique self-interaction potential depending on one coupling constant. For a vanishing coupling constant, this potential reduces to a mass term with a mass fixed in terms of the nonminimal coupling parameter. This mass dependence allows the existence of several free cases including massless and tachyonic sources. There even exists a particular value of the nonminimal coupling parameter for which the corresponding mass exactly compensates the contribution generated by the negative scalar curvature, producing a genuinely massless field in this curved background. The self-interacting case is studied in detail for the conformal coupling. The resulting gravitational wave is formed by the superposition of the free and the self-interaction contributions, except for a critical value of the coupling constant where a non-perturbative effect relating the strong and weak regimes of the source appears. We establish a correspondence between the scalar source supporting an AdS wave and a pp wave by showing that their respective pure radiation constraints are conformally related, while their involved backgrounds are not. Finally, we consider the AdS waves for topologically massive gravity and its limit to conformal gravity.Comment: 26 pages, 1 figure. Minor change

Deeper discussion of Schr\"odinger invariant and Logarithmic sectors of higher-curvature gravity

The aim of this paper is to explore D-dimensional theories of pure gravity whose space of solutions contains certain class of AdS-waves, including in particular Schrodinger invariant spacetimes. This amounts to consider higher order theories, and the natural case to start with is to analyze generic square-curvature corrections to Einstein-Hilbert action. In this case, the Schrodinger invariant sector in the space of solutions arises for a special relation between the coupling constants appearing in the action. On the other hand, besides the Schrodinger invariant configurations, logarithmic branches similar to those of the so-called Log-gravity are also shown to emerge for another special choice of the coupling constants. These Log solutions can be interpreted as the superposition of the massless mode of General Relativity and two scalar modes that saturate the Breitenlohner-Freedman bound (BF) of the AdS space on which they propagate. These solutions are higher-dimensional analogues of those appearing in three-dimensional massive gravities with relaxed AdS_3 asymptotic. Other sectors of the space of solutions of higher-curvature theories correspond to oscillatory configurations, which happen to be below the BF bound. Also, there is a fully degenerated sector, for which any wave profile is admitted. We comment on the relation between this degeneracy and the non-renormalization of the dynamical exponent of the Schrodinger spaces. Our analysis also includes more general gravitational actions with non-polynomial corrections consisting of arbitrary functions of the square-curvature invariants. The same sectors of solutions are shown to exist for this more general family of theories. We finally consider the Chern-Simons modified gravity in four dimensions, for which we derive both the Schrodinger invariant as well as the logarithmic sectors.Comment: This paper is dedicated to the memory of Laurent Houar

Hydrodynamic force on a small squirmer moving with a time-dependent velocity at small Reynolds numbers

We calculate the hydrodynamic force on a small spherical, unsteady squirmer moving with a time-dependent velocity in a fluid at rest, taking into account convective and unsteady fluid-inertia effects in perturbation theory. Our results generalise those of Lovalenti and Brady (1993) from passive to active spherical particles. We find that convective inertia changes the history contribution to the hydrodynamic force, as it does for passive particles. We determine how the hydrodynamic force depends on the swimming gait of the unsteady squirmer. Since swimming breaks the spherical symmetry of the problem, the force is not completely determined by the outer solution of the asymptotic-matching problem, as it is for passive spheres. There are additional contributions brought by the inhomogeneous solution of the inner problem. We also compute the disturbance flow, illustrating convective and unsteady fluid-inertia effects for a sudden start of the centre-of-mass motion, and for swimming with a periodic gait. We discuss the implications of our findings for small motile organisms in a marine environment.Comment: 16 pages, 4 figure