Regularity of Tor for weakly stable ideals

It is proved that if $I$ and $J$ are weakly stable ideals in a polynomial ring $R=k[x_1,\ldots,x_n]$, with $k$ a field, then the regularity of $\text{Tor}^R_i(R/I,R/J)$ has the expected upper bound. We also give a bound for the regularity of $\text{Ext}_R^i(R/I,R)$ for $I$ a weakly stable ideal

Gossip and Metaphysics: The Personal Turn in Jurisprudential Writing

A Review of Neil Duxbury, Patterns of American Jurisprudence and John Henry Schlegel American Legal Realism and Empirical Social Scienc

Porque la tierra y la libertad les eran ajenas. Campesinos rebeldes en Bolivia, 1927-1953

Este artículo expone resultados parciales de dos investigaciones que se ocupan de la violencia en el mundo rural en América Latina. En este texto se analiza la insurgencia de los campesinos bolivianos entre 1927 (rebelión en Chayanta) y 1953 (ley de Reforma Agraria). En esos casi treinta años, los campesinos devinieron sujetos principales de las luchas sociales y políticas del país, protagonismo que no abandonaron y que a menudo compartieron / confrontaron con los obreros mineros e incluso, más allá del tiempo aquí analizado, con las Fuerzas Armadas (pacto militar-campesino). Las investigaciones en curso indagan las condiciones socio-históricas que hacen posible la rebelión, las que, en el caso boliviano, incluyen las brutales condiciones de dominación y explotación de los indígenas campesinos, particularmente duras en las haciendas, en las cuales subsistían hasta la Revolución Nacional, la institución colonial del pongueaje. La Guerra del Chaco, primero, y las políticas reformistas de los presidentes Toro, Busch y, sobre todo, Villarroel, generaron una situación favorable para la toma de conciencia, la organización y el decidido paso a la acción campesinas, cambiando radicalmente el curso de la historia de la clase y del paísEste artigo apresenta resultados parciais de duas pesquisas que se interessam pela violência no mundo rural na América Latina. Neste texto se analisa a insurgência dos camponeses bolivianos entre 1927 (rebelião de Chayanta) e 1953 (Lei de Reforma agrária). Nestes quase trinta anos, os camponeses deviram sujeitos principais das lutas sociais e políticas do país, protagonismo que não abandonaram e que com frequência compartilharam/confrontaram com os operários mineiros e incluso, além do tempo aqui analisado, com as Forças Armadas (Pacto militar-camponês). As pesquisas em andamento indagam as condições socio-históricas que fazem possível a rebelião, as que, no caso boliviano, incluem as brutais condições de dominação e exploração dos indígenas camponeses, particularmente duras nas fazendas, nas quais subsistiam até a Revolução Nacional, a instituição colonial do pongueaje. A Guerra do Chaco, primeiro, e as políticas reformistas dos presidentes Toro, Busch e, sobretudo, Villarroel, geraram uma situação favorável para a toma de consciência, a organização e o decidido passo à acção camponesa, mudando radicalmente o curso da história da classe e do paísFil: Ansaldi, Waldo Argentino. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigación de América Latina y el Caribe; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

La cuestión de la democracia y la democracia en cuestión

El trabajo tiene como punto de partida el estado de situación actual de América Latina,donde la mayoría de los países que la integran vive desde hace unas décadas un ciclo históricamente excepcional de continuidad político-institucional fundada en regímenes políticos democráticos. Este ciclo se inició en 1979 en Perú y Ecuador, y continuó en 1982 en Bolivia, en 1983 en Argentina, en 1984 en El Salvador, en 1985 en Uruguay y Brasil, en 1986 en Guatemala, en 1989 en Chile y Paraguay. México, Costa Rica, Venezuela, Nicaragua, Colombia y, obviamente, Cuba constituyen, por diferentes razones, casos con otras características, al tiempo que Uruguay y Chile, que antes de 1973 supieron ser sociedades sin rupturas de la señalada continuidad,recuperaron su tradición democrática o inventaron una nueva. Tanto políticos como cien-tíficos sociales definieron una agenda de análisis, reflexiones y acciones centrada en dos conceptos centrales: transición de dictaduras a democracia y democracia. El autor historiza el debate sobre la democracia en América Latina, desde la Conferencia Regional sobre Condiciones Sociales de la Democracia, organizada por el Consejo Latinoamericano de Ciencias Sociales (CLACSO) y se propone aportar a una discusión que estima necesaria,centrada en la pregunta: ¿Qué democracia queremos?This paper is a starting point the status of currentsituation of Latin America, where the majority of the countries that integrate it lives from afew decades ago a cycle historically has exceptional institutional continuity established in democratic political regimes.This cycle began in 1979 in Peru and Ecuador,and continued in 1982 in Bolivia, in 1983 inArgentina, in 1984 in El Salvador in 1985 inUruguay and Brazil, in 1986 in Guatemala in 1989 in Chile and Paraguay. Mexico, CostaRica, Venezuela, Nicaragua, Colombia and,obviously, Cuba constitute, for differentreasons, cases with other features, whileUruguay and Chile before 1973 learnedsocieties without designated continuitybreaks, recovered its democratic tradition orinvented a new. Both politicians how socialscientists defined an agenda of analysis,reflections and actions focused on two centralconcepts: transition from dictatorships todemocracy and democracy. The authorhistoricized the debate on democracy inLatin America, since the Regional Conferenceon social conditions of democracy, organizedby the Latin American Council of socialsciences (CLACSO) and intends to contribute to a discussion which considersnecessary, focused on the question: do wewant democracy?Fil: Ansaldi, Waldo Argentino. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigación de América Latina y el Caribe; Argentin

América Latina, una liebre muy esquiva

Las entusiastas animadoras del GESCAL me han pedido que escriba, a manera de prólogo de este libro, un breve texto sobre “líneas para estudiar e investigar América Latina”. He aceptado complacido la invitación: por latinoamericano y latinoamericanista y porque soy un entusiasta de este hermoso proyecto impulsado por muchachas y muchachos estudiantes de Colombia en Universidades argentinas, proyecto que conozco, comparto y apoyo desde su gestación en Córdoba. Dicho sea al pasar, tal vez no sea casual que esta apuesta haya comenzado en la misma Universidad en la cual se gestó la Reforma Universitaria, expresión pionera de latinoamericanismo estudiantilFil: Ansaldi, Waldo Argentino. Universidad de Buenos Aires. Facultad de Ciencias Sociales. Instituto de Investigación de América Latina y el Caribe; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Non viscous sensitivity analysis of noise generation mechanism in a low Mach number jet

The first step of the sensitivity analysis of some quadratic quantity related to acoustic waves with respect to any flow or wall disturbance is proposed in the configuration of subsonic jet flow. The generation of noise has been demonstrated to originate from convective instabilities that amplify in the jet stream. Several authors have investigated them through the Parabolized Stability Equations approach (PSE). The present work aims to develop the adjoint of the PSE to extract from a mathematically well posed problem the sensitivity coefficients which can be understood as gradient. The final objective is to propose some path of possible actuations in order to decrease noise emission in some jet flows. To date some trend can be given. The shape and the location of the maximum of sensitivity are strongly related to the radial and streamwise variation of the base flow. In particular the maximum of sensitivity is located along the border of the potential cone and seems to be well correlated with the location of the sound generation mechanism. In addition the sensitivity to axial momentum forcing is higher than to a radial momentum forcing. Finally the sensitivity increases when the perturbation is near to the exit of the nozzle

Sensitivity analysis for subsonic jet using adjoint of non local stability equations

The first step of the sensitivy analysis of some quadratic quantity related to acoustic waves with respect to any flow or wall disturbance is proposed in the configuration of a low and large Reynolds number jet flow. The generation of noise has been demonstrated to originate from convective instabilities amplifying in the jet stream. Several authors have investigated them throught the Parabolized Stability Equations approach(PSE). The present work aims to developp the adjoint of the PSE to extract from a mathematically well posed problem the sensitivity coefficients which can be understood as gradient. The final aim is to propose some path of possible actuations in order to decrease noise emission in some jet flows. Event is it is too early to produce some final conclusions, some trend can be given. The shape and the location of the maximun of sensitivity are strongly related to the radial and streamwise variation of the base flow. In particuler the maximun of sensitivy is located along the border of the potential cone and seems to be well correlated with the location of the sound generation. In addition the sensitivity to radial momentum forcing is much higher than to a streamwise momentum forcing. Finally the sensitivity increases when the streamwise coordinate decreases

Design and throughput simulations of a hard x-ray split and delay line for the MID station at the European XFEL

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in AIP Conference Proceedings 1741, 030010 (2016) and may be found at https://doi.org/10.1063/1.4952833.A hard X-ray Split and Delay Line (SDL) under development for the Materials Imaging and Dynamics (MID) station at the European X-Ray Free-Electron Laser (XFEL.EU) is presented. This device will provide pairs of X-ray pulses with a variable time delay ranging from −10 ps to 800 ps in a photon energy range from 5 to 10 keV. Throughput simulations in the SASE case indicate a total transmission of 1.1% or 3.5% depending on the operation mode. In the self-seeded case of XFEL.EU operation simulations indicate that the transmission can be improved to more than 11%.BMBF, 05K13KT4, Verbundprojekt FSP 302 - Freie-Elektronen-Laser: Nanoskopische Systeme. Teilprojekt 1: Split-and-Delay Instrument für die European XFEL Beamline Materials Imaging and Dynamic