Manejo integrado de Moniliasis (Moniliophthora roreri) en cacao (Theobroma cacao) y su impacto en el rendimiento, Cooperativa Flor de Pancasán 2014-2015

El presente estudio se llevó a cabo en dos fincas de socios de la Cooperativa “Flor de Pancasán” ubicada en la comarca de Pancasán Sitio Histórico, municipio de Matiguas, durante el II semestre del año 2014-2015, con el objetivo de evaluar el efecto del manejo integrado de Moniliasis (Moniliophthora roreri) en el cultivo de cacao (Theobroma cacao) sobre rendimientos productivos. Es una investigación experimental y de corte transversal, la población de estudio estuvo conformada por las plantas de cacao presentes en las parcelas experimentales, siendo la muestra de 32 plantas/parcela. Para recopilar la información necesaria se utilizaron hojas de campo y observación directa, se hizo uso de los programas estadísticos Excel y SPSS v.19 para realizar análisis estadísticos y elaborar gráficos. Los resultados encontrados demuestran que existe diferencia significativa entre las plantaciones de estudio de acuerdo al grado de incidencia de la enfermedad, con la aplicación de los fungicidas químicos (Enlazador X2), y fungicida orgánico (extracto de jengibre). Se consiguió reducir la incidencia de la enfermedad de manera significativa, demostrando los beneficios de ambos. En lo que respecta a la relación costos/beneficios en ambos experimentos, el tratamiento que posee la mejor rentabilidad es el tratamiento 3 (extracto de jengibre). Las alternativas para reducir la incidencia de moniliasis son realizar un control integrado de la enfermedad, la remoción de frutos enfermos cada 15 días, depositándolos en fosa excavada para tal efecto, así como la realización de podas para la regulación de sombra. Palabras claves: moniliasis, manejo integrado, rendimientos, costos, beneficios, incidenci

Tensor products of subspace lattices and rank one density

We show that, if $M$ is a subspace lattice with the property that the rank one subspace of its operator algebra is weak* dense, $L$ is a commutative subspace lattice and $P$ is the lattice of all projections on a separable infinite dimensional Hilbert space, then the lattice $L\otimes M\otimes P$ is reflexive. If $M$ is moreover an atomic Boolean subspace lattice while $L$ is any subspace lattice, we provide a concrete lattice theoretic description of $L\otimes M$ in terms of projection valued functions defined on the set of atoms of $M$. As a consequence, we show that the Lattice Tensor Product Formula holds for \Alg M and any other reflexive operator algebra and give several further corollaries of these results.Comment: 15 page

Compactness properties of operator multipliers

We continue the study of multidimensional operator multipliers initiated in [arXiv:math/0701645]. We introduce the notion of the symbol of an operator multiplier. We characterise completely compact operator multipliers in terms of their symbol as well as in terms of approximation by finite rank multipliers. We give sufficient conditions for the sets of compact and completely compact multipliers to coincide and characterise the cases where an operator multiplier in the minimal tensor product of two C*-algebras is automatically compact. We give a description of multilinear modular completely compact completely bounded maps defined on the direct product of finitely many copies of the C*-algebra of compact operators in terms of tensor products, generalising results of Saar

Green function techniques in the treatment of quantum transport at the molecular scale

The theoretical investigation of charge (and spin) transport at nanometer length scales requires the use of advanced and powerful techniques able to deal with the dynamical properties of the relevant physical systems, to explicitly include out-of-equilibrium situations typical for electrical/heat transport as well as to take into account interaction effects in a systematic way. Equilibrium Green function techniques and their extension to non-equilibrium situations via the Keldysh formalism build one of the pillars of current state-of-the-art approaches to quantum transport which have been implemented in both model Hamiltonian formulations and first-principle methodologies. We offer a tutorial overview of the applications of Green functions to deal with some fundamental aspects of charge transport at the nanoscale, mainly focusing on applications to model Hamiltonian formulations.Comment: Tutorial review, LaTeX, 129 pages, 41 figures, 300 references, submitted to Springer series "Lecture Notes in Physics

Ideals of A(G) and bimodules over maximal abelian selfadjoint algebras

This paper is concerned with weak* closed masa-bimodules generated by A(G)-invariant subspaces of VN(G). An annihilator formula is established, which is used to characterise the weak* closed subspaces of B(L^2(G)) which are invariant under both Schur multipliers and a canonical action of M(G) on B(L^2(G)) via completely bounded maps. We study the special cases of extremal ideals with a given null set and, for a large class of groups, we establish a link between relative spectral synthesis and relative operator synthesis.Comment: Please refer to the journal for the final versio

Ranges of bimodule projections and reflexivity

We develop a general framework for reflexivity in dual Banach spaces, motivated by the question of when the weak * closed linear span of two reflexive masa-bimodules is automatically reflexive. We establish an affirmative answer to this question in a number of cases by examining two new classes of masa-bimodules, defined in terms of ranges of masa-bimodule projections. We give a number of corollaries of our results concerning operator and spectral synthesis, and show that the classes of masa-bimodules we study are operator synthetic if and only if they are strong operator Ditkin. © 2012

Bimodules over VN(G), harmonic operators and the non-commutative Poisson boundary

Starting with a left ideal J of L1(G) we consider its annihilator J in L∞(G) and the generated VN(G)-bimodule in B(L2(G)), Bim(J). We prove that Bim(J) = (Ran J) when G is weakly amenable discrete, compact or abelian, where Ran J is a suitable saturation of J in the trace class. We define jointly harmonic functions and jointly harmonic operators and show that, for these classes of groups, the space of jointly harmonic operators is the VN(G)-bimodule generated by the space of jointly harmonic functions. Using this, we give a proof of the following result of Izumi and Jaworski–Neufang: the non-commutative Poisson boundary is isomorphic to the crossed product of the space of harmonic functions by G. © Instytut Matematyczny PAN, 201

Operator algebras from the discrete Heisenberg semigroup

We study reflexivity and structural properties of operator algebras generated by representations of the discrete Heisenberg semigroup. We show that the left regular representation of this semigroup gives rise to a semi-simple reflexive algebra. We exhibit an example of a representation that gives rise to a non-reflexive algebra. En route, we establish reflexivity results for subspaces of H∞ (T)⊗ B(H). © 2011 Edinburgh Mathematical Society

Ideals of A(G) and bimodules over maximal abelian selfadjoint algebras

This paper is concerned with weak* closed masa-bimodules generated by A(G)-invariant subspaces of VN(G). An annihilator formula is established, which is used to characterise the weak* closed subspaces of B(L2(G)) which are invariant under both Schur multipliers and a canonical action of M(G) on B(L2(G)) via completely bounded maps. We study the special cases of extremal ideals with a given null set and, for a large class of groups, we establish a link between relative spectral synthesis and relative operator synthesis. © 2014