Multimetric Supergravities

Making use of integral forms and superfield techniques we propose supersymmetric extensions of the multimetric gravity Lagrangians in dimensions one, two, three and four. The supersymmetric interaction potential covariantly deforms the bosonic one, producing in particular suitable super-symmetric polynomials generated by the Berezinian. As an additional application of our formalism we construct supersymmetric multi-Maxwell theories in dimensions three and four.Comment: 37 pages, Latex2e, no figure

Massless fermions in a bag at finite density and temperature

We introduce the chemical potential in a system of massless fermions in a bag by impossing boundary conditions in the Euclidean time direction. We express the fermionic mean number in terms of a functional trace involving the Green's function of the boundary value problem, which we study analytically. Numerical evaluations are made, and an application to a simple hadron model is discussed.Comment: 14 pages, 3 figures, RevTe

On the relation between local and geometric Lagrangians for higher spins

Equations of motion for free higher-spin gauge fields of any symmetry can be formulated in terms of linearised curvatures. On the other hand, gauge invariance alone does not fix the form of the corresponding actions which, in addition, either contain higher derivatives or involve inverse powers of the d'Alembertian operator, thus introducing possible subtleties in degrees of freedom count. We suggest a path to avoid ambiguities, starting from local, unconstrained Lagrangians previously proposed, and integrating out the auxiliary fields from the functional integral, thus generating a unique non-local theory expressed in terms of curvatures.Comment: 14 pages. Contribution to the proceedings of the 1st Mediterranean Conference on Classical and Quantum Gravity, Kolymbary (Crete, Greece) September 14-18 200

Finite density and temperature in hybrid bag models

We introduce the chemical potential in a system of two-flavored massless fermions in a chiral bag by imposing boundary conditions in the Euclidean time direction. We express the fermionic mean number in terms of a functional trace involving the Green function of the boundary value problem, which is studied analytically. Numerical evaluations for the fermionic number are presented.Comment: 19 pages, 4 figure

Half-integer Higher Spin Fields in (A)dS from Spinning Particle Models

We make use of O(2r+1) spinning particle models to construct linearized higher-spin curvatures in (A)dS spaces for fields of arbitrary half-integer spin propagating in a space of arbitrary (even) dimension: the field potentials, whose curvatures are computed with the present models, are spinor-tensors of mixed symmetry corresponding to Young tableaux with D/2 - 1 rows and r columns, thus reducing to totally symmetric spinor-tensors in four dimensions. The paper generalizes similar results obtained in the context of integer spins in (A)dS.Comment: 1+18 pages; minor changes in the notation, references updated. Published versio

Maxwell-like Lagrangians for higher spins

We show how implementing invariance under divergence-free gauge transformations leads to a remarkably simple Lagrangian description of massless bosons of any spin. Our construction covers both flat and (A)dS backgrounds and extends to tensors of arbitrary mixed-symmetry type. Irreducible and traceless fields produce single-particle actions, while whenever trace constraints can be dispensed with the resulting Lagrangians display the same reducible, multi-particle spectra as those emerging from the tensionless limit of free open-string field theory. For all explored options the corresponding kinetic operators take essentially the same form as in the spin-one, Maxwell case.Comment: 77 pages, revised version. Erroneous interpretation and proof of the gauge-fixing procedure for mixed-symmetry fields corrected. As a consequence, the mixed-symmetry, one-particle Lagrangians are to be complemented with conditions on the divergences of the fields; all other conclusions unchanged. Additional minor changes including references added. To appear in JHE

Quantum theories of (p,q)-forms

We describe quantum theories for massless (p,q)-forms living on Kaehler spaces. In particular we consider four different types of quantum theories: two types involve gauge symmetries and two types are simpler theories without gauge invariances. The latter can be seen as building blocks of the former. Their equations of motion can be obtained in a natural way by first-quantizing a spinning particle with a U(2)-extended supersymmetry on the worldline. The particle system contains four supersymmetric charges, represented quantum mechanically by the Dolbeault operators and their hermitian conjugates. After studying how the (p,q)-form field theories emerge from the particle system, we investigate their one loop effective actions, identify corresponding heat kernel coefficients, and derive exact duality relations. The dualities are seen to include mismatches related to topological indices and analytic torsions, which are computed as Tr(-1)^F and Tr[(-1)^F F] in the first quantized supersymmetric nonlinear sigma model for a suitable fermion number operator F.Comment: 44 pages, 2 figures, a reference adde

Fractura Supracondílea de Humero en Niños: (estudio de la Rigidez Postquirúgica del Codo en 100 Casos Intervenidos a través de un Abordaje Posterior)

El tratamiento de las fracturas supracondíleas de húmero desplazadas en niños mediante reducción abierta y fijación interna es un procedimiento poco utilizado y que no goza del favor de la mayoría de los cirujanos ortopédicos, debido principalmente a la pérdida permanente de movilidad en el codo que se atribuye a esta técnica. Según algunos autores ésta pérdida es mayor aún si se utiliza un abordaje posterior. Se presenta una importante casuística (100 casos) de fracturas muy desplazadas que han sido tratadas mediante reducción abierta y fijación por vía posterior y revisadas a largo plazo. La rigidez postquirúrgica encontrada es en general leve, e inferior si se utiliza un abordaje quirúrgico que respete la integridad anatómica del músculo tríceps.Treatment of displaced supracondylar fractures of the humerus in children by open reduction and internal fixation is a little-used therapeutic method and ill-advised by many authors owing to permanent stiffness of the elbow using this procedure. An important series of 100 very displaced fractures treated by open reduction and fixation from a posterior approach and is slight and less using a surgical approach which respects the anathomic of triceps muscle

The inclusion of fresh forage in the lactating buffalo diet affects fatty acid and sensory profile of mozzarella cheese

The aim of this study was to determine the effect of inclusion of fresh forage in diet for lactating buffalo on properties of mozzarella cheese under intensive farming conditions. Thirty-two buffalo cows were equally allotted into 2 groups fed diets with (fresh group, FRS) or without (control group, CTL) fresh sorghum. The study consisted of 2 trials. In the first one, animals from group FRS were fed a diet containing 10 kg of fresh sorghum (10-FRS diet) that was doubled to 20 kg (20-FRS diet) in the second trial. All diets were isonitrogenous and isoenergetic, and fresh forage accounted for 13.4 and 26.5 of dietary dry matter, respectively, for the 10-FRS and 20-FRS diet. In each trial, milk from the 2 groups was used to produce 3 batches/diet of Mozzarella di Bufala Campana Protected Designation of Origin cheese. Milk yield and composition were not influenced by dietary treatment. The use of 10-FRS diet did not affect any properties of mozzarella. As the inclusion rate of fresh sorghum doubled to 20 kg, an increment of unsaturated fatty acid percentages and a lowering of short-chain and saturated fatty acids were observed. Moreover, the sensory characteristics of mozzarella were modified, although no effects were observed on consumer acceptance. We conclude that the use of green fodder can represent a low-cost feeding strategy to improve the healthiness of buffalo mozzarella under intensive farming conditions with no detrimental effect on consumer blind acceptance