Polynomial Observables in the Graph Partitioning Problem

Although NP-Complete problems are the most difficult decisional problems, it is possible to discover in them polynomial (or easy) observables. We study the Graph Partitioning Problem showing that it is possible to recognize in it two correlated polynomial observables. The particular behaviour of one of them with respect to the connectivity of the graph suggests the presence of a phase transition in partitionability.Comment: 7 pages, 2 figure

Diritto all'istruzione e integrazione dei rifugiati

This article focuses on the right to education within the context of the integration of refugees. The author underlines that this right is an essential instrument to create a strong relation between the individual and the society. In this line, he strongly contest the argument that education is only a basic need, not an enforceable right. Furthermore, education is considered as the cornerstone in the promotion and the protection of human rights and as a precondition for the integration of asylum seekers into national systems. Thus, the author analyses in depth the legal framework of the right to education at the European and international levels, as well as in the Italian legal order, with the aim to demonstrate its relevance in the integration of refugees

Neutrino neutral reaction on 4He, effects of final state interaction and realistic NN force

The inelastic neutral reaction of neutrino on 4He is calculated microscopically, including full final state interaction among the four nucleons. The calculation is performed using the Lorentz integral transform (LIT) method and the hyperspherical-harmonic effective interaction approach (EIHH), with a realistic nucleon-nucleon interaction. A detailed energy dependent calculation is given in the impulse approximation. With respect to previous calculations, this work predicts an increased reaction cross-section by 10%-30% for neutrino temperature up to 15 MeV.Comment: 4 pages, 2 fig

Lorentz Integral Transform for Inclusive and Exclusive Cross Sections with the Lanczos Method

The Lorentz Integral Transform (LIT) method is reformulated via the Lanczos algorithm both for inclusive and exclusive reactions. The new technique is tested for the total photoabsorption cross section of 3H and 4He. Due to the rapid convergence of the algorithm one has a decrease in cpu time by two orders of magnitude, but at the same time an excellent agreement with the results of a conventional LIT calculation. The present work opens up the possibility of ab initio calculations for inclusive and exclusive processes for A greater equal 6 with inclusion of complete final state interactions.Comment: LaTeX, 13 pages, 3 ps figure

Lactancias extendidas en sistemas de producción lechera argentinos

En la Argentina los sistemas de producción de leche utilizan animales mejorados genéticamente para producir en condiciones de dietas muy suplementadas en planteos productivos de base pastoril con suplementación. En estos sistemas el objetivo es obtener un parto por vaca por año pero son muy pocos los tambos que llegan a cumplirlo porque se atrasa el momento de la concepción prolongando las lactancias. El objetivo del trabajo fue investigar los factores que influyen en la productividad de tambos ubicados en el centro de la provincia de Santa Fe y las razones que determinan la duración de las lactancias en estos tambos con el fin de analizar estrategias de manejo que consideren el uso de lactancias extendidas para lograr aumentos de productividad sostenibles. Adicionalmente se exploraron aquellos factores reproductivos asociados al largo de lactancia, como determinante de los litros totales producidos por vaca. Se analizó información de 1620 vacas de once tambos, recolectada en junio de 2008. Para cada tambo y para el conjunto de tambos se estimaron los valores promedio y desvío estándar del porcentaje de vacas secadas antes de los 365 días en lactancia (DEL), porcentaje de vacas vacías con más de 200 DEL y los servicios por vaca hasta confirmar preñez. En las vacas que cerraron su lactancia durante el periodo julio 2007 - junio 2008 (n igual a 892) se estimó la producción de leche acumulada al fin de la lactancia (PT), la producción de leche diaria (PD) y el valor de DEL. Además se estimó la producción de leche por hectárea y la carga animal. Los datos se analizaron por regresión lineal. Para explorar la relación entre PT con PD y DEL se hizo un análisis de regresión múltiple. En los casos analizados el aumento en la duración de la lactancia sería consecuencia de un atraso en el logro de preñez con un impacto relativamente bajo sobre la productividad de los sistemas

Computational design of synthetic gene circuits with composable parts

Motivation: In principle, novel genetic circuits can be engineered using standard parts with well-understood functionalities. However, no model based on the simple composition of these parts has become a standard, mainly because it is difficult to define signal exchanges between biological units as unambiguously as in electrical engineering. Corresponding concepts and computational tools for easy circuit design in biology are missing. Results: Taking inspiration from (and slightly modifying) ideas in the ‘MIT Registry of Standard Biological Parts', we developed a method for the design of genetic circuits with composable parts. Gene expression requires four kinds of signal carriers: RNA polymerases, ribosomes, transcription factors and environmental ‘messages' (inducers or corepressors). The flux of each of these types of molecules is a quantifiable biological signal exchanged between parts. Here, each part is modeled independently by the ordinary differential equations (ODE) formalism and integrated into the software ProMoT (Process Modeling Tool). In this way, we realized a ‘drag and drop' tool, where genetic circuits are built just by placing biological parts on a canvas and by connecting them through ‘wires' that enable flow of signal carriers, as it happens in electrical engineering. Our simulations of well-known synthetic circuits agree well with published computational and experimental results. Availability: The code is available on request from the authors. Contact: [email protected] Supplementary information: Supplementary data are available at Bioinformatics onlin

L'utilizzo delle categorie giuridiche del diritto internazionale nel processo d'unificazione italiana

la questione dei modi concreti e degli aspetti giuridici relativi al percorso d’unificazione italiana ha, nel tempo, originato una vivace dialettica relativa a taluni presunti vizi d’origine dagli studi in materia è emersa una netta divisione di vedute il dibattito relativo all’unificazione italiana è stato sempre animato da posizioni elogiative e critiche dell’Unità. Al fine di ricostruire gli aspetti giuridici, dal punto di vista del diritto internazionale, del percorso risorgimentale, è utile tenere in considerazione alcuni elementi il primo elemento è senz'altro l'emergere del principio di nazionalità, considerato 'miracoloso' dal momento che, in base ad esso, un popolo unito culturalmente e socialmente, ma diviso politicamente e istituzionalmente, è diventato una Nazion