Complete intersections in binomial and lattice ideals

For the family of graded lattice ideals of dimension 1, we establish a complete intersection criterion in algebraic and geometric terms. In positive characteristic, it is shown that all ideals of this family are binomial set theoretic complete intersections. In characteristic zero, we show that an arbitrary lattice ideal which is a binomial set theoretic complete intersection is a complete intersection.Comment: Internat. J. Algebra Comput., to appea

Computing the degree of a lattice ideal of dimension one

We show that the degree of a graded lattice ideal of dimension 1 is the order of the torsion subgroup of the quotient group of the lattice. This gives an efficient method to compute the degree of this type of lattice ideals.Comment: J. Symbolic Comput., to appea

Nikishin systems are perfect

K. Mahler introduced the concept of perfect systems in the general theory he developed for the simultaneous Hermite-Pade approximation of analytic functions. We prove that Nikishin systems are perfect providing, by far, the largest class of systems of functions for which this important property holds. As consequences, in the context of Nikishin systems, we obtain: an extension of Markov's theorem to simultaneous Hermite-Pade approximation, a general result on the convergence of simultaneous quadrature rules of Gauss-Jacobi type, the logarithmic asymptotics of general sequences of multiple orthogonal polynomials, and an extension of the Denisov-Rakhmanov theorem for the ratio asymptotics of mixed type multiple orthogonal polynomials.Comment: 39 page

Interacting fermions and domain wall defects in 2+1 dimensions

We consider a Dirac field in 2+1 dimensions with a domain wall like defect in its mass, minimally coupled to a dynamical Abelian vector field. The mass of the fermionic field is assumed to have just one linear domain wall, which is externally fixed and unaffected by the dynamics. We show that, under some general conditions on the parameters, the localized zero modes predicted by the Callan and Harvey mechanism are stable under the electromagnetic interaction of the fermions

A clinical evaluation of the use of an electroanesthetic handpiece in children

Thesis (M.Sc.D.)--Boston University School of Graduate Dentistry, 1973. Pedodontics.Bibliography included

Effects of a physical activity program on the physical fitness of schoolchildren with ADHD

Este artículo se centra en estudiar los efectos de un programa de actividad física sobre la condición física de un grupo de escolares con TDAH. MÉTODO: Han participado 12 escolares (12 niños), entre los 7 y los 12 años de edad. La condición física se ha medido mediante dinamometría manual, salto horizontal y Course-Navette. El procedimiento ha sido: pre-test, intervención y pos-test. La intervención ha consistido en 2 días a la semana de actividad física, 60 minutos al día, durante 12 semanas. RESULTADOS Y DISCUSIÓN: Se han producido mejoras significativas en condición física [capacidad músculo-esquelética del tren inferior (p=0.037) y capacidad aeróbica (p=0,011)]. CONCLUSIONES: El programa utilizado es eficaz para mejorar la condición física de niños con TDAH

Investigation of the importance of cumulus convection and ventilation in early tropical storm development

June 1968.Includes bibliographical references.Sponsored by ESSA E-22-80-68(G).Sponsored by NSF GF-287