The Chihuahua trade monopoly in New Mexico, 1800-1821

Thesis (M.A.)--University of Oklahoma, 1986.Bibliography: leaves 206-215

Stock piling of strategic materials

Thesis (M.B.A.)--Boston Universit

Phase Diagram of the Kane-Mele-Hubbard model

Motivated by recent numerical results, we study the phase diagram of the Kane-Mele-Hubbard (KHM) model, especially the nature of its quantum critical points. The phase diagram of the Kane-Mele-Hubbard model can be understood by breaking the SO(4) symmetry of our previous work down to U(1)_spin x U(1)_charge x PH symmetry. The vortices of the inplane Neel phase carry charge, and the proliferation of the charged magnetic vortex drives the transition between the inplane Neel phase and the QSH insulator phase; this transition belongs to the 3d XY universality class. The transition between the liquid phase and the inplane Neel phase is an anisotropic O(4) transition, which eventually becomes first order due to quantum fluctuation. The liquid-QSH transition is predicted to be first order based on a 1/N calculation.Comment: 5 pages, 2 figure

Modified procedure to assess dna breakage in spermatozoa by means of the comet assay

The comet assay is a relatively inexpensive, fast, sensitive and reliable method to detect DNA breakage upon individual cells. The most widely used cell type in this technique is lymphocyte, because they are easy to obtain and handle, and because they are continually exposed to xenobiotics that enter into the body. However, is important to consider the possibility to use other cell types for very specific purposes. Sperm cells are of special interest because they could be used as a biomonitor to risk assessment in populations occupationally exposed to xenobiotics. Besides, the fact that there are not functional DNA repair mechanisms in these cells could increase the sensitivity of the system. We present here several modifications to the comet assay methodology to evaluate DNA breakage in sperm cells with reliable results

Cement tiles, a forgotten art of Modernism

[SPA] Como resultado de una profunda investigación de casi veinte años, este trabajo descubre la historia del mosaico hidráulico: antecedentes, orígenes e implantación, principales fabricantes, materiales, técnicas de fabricación, evolución de sus diseños, calidad del trabajo y artistas y arquitectos de primera línea que diseñaron y aplicaron este tipo de pavimento que, afortunadamente, todavía hoy puede contemplarse en muchos interiores del país y del extranjero. [ENG] As a result of an extensive research of nearly twenty years, this work reveals the history of cement tiles: history, origins and implementation, main manufacturers, materials, manufacturing techniques, evolution of their designs, quality of work and important artists and architects who designed and implemented this type of pavement than, fortunately, can still be seen in many interiors of the country and abroad

Deformed triangular lattice antiferromagnets in a magnetic field: role of spatial anisotropy and Dzyaloshinskii-Moriya interactions

Recent experiments on the anisotropic spin-1/2 triangular antiferromagnet Cs_2CuBr_4 have revealed a remarkably rich phase diagram in applied magnetic fields, consisting of an unexpectedly large number of ordered phases. Motivated by this finding, we study the role of spatial anisotropy, Dzyaloshinskii-Moriya interactions, and quantum fluctuations on the magnetization process of a triangular antiferromagnet, coming from the semiclassical limit. The richness of the problem stems from two key facts: 1) the classical isotropic model exhibits a large accidental ground state degeneracy, and 2) these three ingredients compete with one another and split this degeneracy in opposing ways. Using a variety of complementary approaches, including extensive Monte Carlo numerics, spin-wave theory, and an analysis of Bose-Einstein condensation of magnons at high fields, we find that their interplay gives rise to a complex phase diagram consisting of numerous incommensurate and commensurate phases. Our results shed light on the observed phase diagram for Cs_2CuBr_4 and suggest a number of future theoretical and experimental directions that will be useful for obtaining a complete understanding of this material's interesting phenomenology.Comment: 22 pages, 16 figures; Submission errors correcte

Les chaotiques débuts de la recherche informatique

Pendant la guerre, à la Libération et jusqu’aux années gaulliennes, la recherche est perçue comme une nécessité pour que la France rattrape ses retards et affirme son rang, éclipsé par les malheurs des années 1930 et 1940. L’État a pesé dans cette orientation politique en s’affirmant par le biais des nationalisations et des créations d’organismes publics dont le plus emblématique fut le Commissariat à l’énergie atomique (1945). Avec la multiplicité des initiatives, la question de la coexistence d’organismes de recherche entre eux s’est imposée. Le CNRS se trouvait au cœur de cette réflexion. Le développement de la recherche informatique prend à ce titre une valeur exemplaire : à qui confier ce secteur nouveau dont les retombées économiques étaient prévisibles et sans doute importantes ?From World War II to the de Gaulle’s years, the scientific research is considered as a necessity that will help France to catch back and find again its rank, after the terrible period of the thirties and forties. The State played a very important role in this political orientation that concretely expressed itself through nationalisations and creations of several public entities – among them the most symbolic: the French Atomic Energy commission (1945). The question of these entities living together and the relationships between them raised and the CNRS became the heart of this debate. Consequently, the computer engineering research becomes a symbol: who will be in charge of this strategic sector with a large economic impact

L' Inria a 40 ans par Pascal Griset. En quarante ans l'informatique a complètement modifié notre société, entretien avec Michel Cosnard, propos recueillis par Dominique Chouchan. Prospective avec Malik Ghallab "sept priorités pour 2008-2012"

National audienceAu cours des dernières années, l'INRIA a connu un développement sans précédent, confirmant son excellence au plan français et européen comme au plan international. En quatre décennies, l'Institut a non seulement su imposer une nouvelle discipline en France, l'informatique, mais aussi allier recherche fondamentale et réponses aux besoins de la société