The Λ0\Lambda_0 Polarization and the Recombination Mechanism

We use the recombination and the Thomas Precession Model to obtain a prediction for the $\Lambda _0$ polarization in the $p+p \to \Lambda_0+X$ reaction. We study the effect of the recombination function on the $\Lambda_0$ polarization.Comment: 4 pages, LaTex, 1 figures included, aipproc.sty included. Talk presented at Simposio Latino Americano de Fisica de Altas Energias, Merida, Mexico, November 199

Alfabetizando al alfabetizador: Mujeres hispanas en un nuevo contexto social

La población hispana en Estados Unidos continúa aumentando establemente y de forma rápida. Este incremento fértil y constante de hispanos ha reorganizado el matiz social del país y expone a los inmigrantes a unas realidades sociales, lingüísticas y educativas no conocidas anteriormente. Estudiantes inmigrantes hispanos aprendices del idioma inglés son inmersos en un sistema educativo completamente desconocido y se enfrentan a un reto lingüístico que necesitan rebasar de forma diligente para tener éxito en sus escuelas. A su vez, los padres inmigrantes atraviesan otros retos similares en sus ambientes laborales en los cuales el idioma y otros componentes sociales les dificultan el éxito profesional y el involucramiento en las escuelas de sus hijos. Este artículo expone las realidades de los estudiantes hispanos y las madres hispanas en Estados Unidos a través de los ojos de cuatro madres hispanas inmigrantes. Mediante la entrevista profunda, este trabajo expone el impacto que tiene la participación parental en el desenvolvimiento escolar y académico de los estudiantes hispanos en Estados Unidos.// The Hispanic population in the United States continues growing steadily and rapidly. This fertile and constant growth has reorganized the country’s social milieu and exposes immigrants to social, linguistic and educational realities that were previously unknown. Hispanic immigrant English Language Learners are immersed in a completely unfamiliar academic system, and face linguistic challenges that must be overcome if they are to be successful in school. In the same way, immigrant parents undergo similar challenges in their work environments in which language and other social barriers impede their professional success and involvement in their children’s academic life. This work presents the experiences of Hispanic students and mothers in the United States through the eyes of four Hispanic immigrant women. In depth interviews were used to test for the impact that parental involvement has in the academic development of Hispanic students in the United States

Sobre la acumulación de riqueza y el futuro de los impuestos progresivos globales en “El Capital en el siglo XXI”, de Thomas Piketty, en el contexto de América Latina

In this essay are analyzed the main economic issues addressed in the book: Capital in the Twenty-First Century by Thomas Piketty, it explores the central thesis of this paper and seeks to explain which are it’s major proposals related to world economic development and the role of institutions in this economic process, with special emphasis on fiscal institutions. In particular, this paper studies the propose of an overall progressive tax on wealth and the fiscal institutions that would support this type of tax and also analyzes the alternatives proposed by the author, referring to deepen the estate tax on large economic units as US the EU. Finally, an analysis of the feasibility of this global tax in Latin America and the historical evolution of the estate tax in this region is made.En el presente ensayo se hace una revista a los principales aspectos económicos tratados en el libro: El Capital en el siglo XXI de Thomas Piketty, se explora la tesis central de este trabajo y se busca explicitar cuáles son sus principales propuestas referidas al desarrollo económico mundial y al papel que juegan las instituciones en este proceso económico, con especial énfasis en las instituciones fiscales. En particular, en este ensayo se estudia la propuesta de un impuesto progresivo global sobre la riqueza y las instituciones fiscales que serían soporte de este tipo de tributo y también se analizan las variantes propuestas por el autor, referidas a profundizar el impuesto al patrimonio en grandes unidades económicas como E.E.U.U. y la U.E.Finalmente se realiza un análisis de la viabilidad de este impuesto global en América Latina y la evolución histórica del impuesto al patrimonio en esta región

Management education in Latin America and the Caribbean.

This paper examines some issues relating to the development in Latin America and the Caribbean of the managerial expertise that underpins the modernisation of library and information services. It reports on part of a joint IFLA/FID project, principally funded by the UNESCO Participation Programme, and reviews results from two surveys: Schools of Librarianship and Information Sciences in the region provided data on the priorities they attach to elements of their management curriculum, and teaching methods; and employers commented on their awareness of modern management techniques, their management development needs and approaches, and their perceptions of the management education available. The results of the two surveys are compared and considered, and some proposals are made for addressing issues. Whilst the Schools appear to be meeting the employers key requirements, there is still some degree of mismatch between employers expectations and Schools priorities, but the Schools are open to change and a constructive dialogue is advocated. It is also suggested that more attention should be given to staff development and the provision of supporting continuing education programmes to raise the level of management knowledge and expertise. Iinternational organisations should consider encouraging the production and exchange of teaching materials. A major challenge for the Schools will be to overcome the traditionally rigid disciplinary boundaries within Universities to collaborate on new course developments

The Epigenetic Origin of Aneuploidy

Theodore Boveri, eminent German pathologist, observed aneuploidy in cancer cells more than a century ago and suggested that cancer cells derived from a single progenitor cell that acquires the potential for uncontrolled continuous proliferation. Currently, it is well known that aneuploidy is observed in virtually all cancers. Gain and loss of chromosomal material in neoplastic cells is considered to be a process of diversification that leads to survival of the fittest clones. According to Darwin’s theory of evolution, the environment determines the grounds upon which selection takes place and the genetic characteristics necessary for better adaptation. This concept can be applied to the carcinogenesis process, connecting the ability of cancer cells to adapt to different environments and to resist chemotherapy, genomic instability being the driving force of tumor development and progression. What causes this genome instability? Mutations have been recognized for a long time as the major source of genome instability in cancer cells. Nevertheless, an alternative hypothesis suggests that aneuploidy is a primary cause of genome instability rather than solely a simple consequence of the malignant transformation process. Whether genome instability results from mutations or from aneuploidy is not a matter of discussion in this review. It is most likely both phenomena are intimately related; however, we will focus on the mechanisms involved in aneuploidy formation and more specifically on the epigenetic origin of aneuploid cells. Epigenetic inheritance is defined as cellular information—other than the DNA sequence itself—that is heritable during cell division. DNA methylation and histone modifications comprise two of the main epigenetic modifications that are important for many physiological and pathological conditions, including cancer. Aberrant DNA methylation is the most common molecular cancer-cell lesion, even more frequent than gene mutations; tumor suppressor gene silencing by CpG island promoter hypermethylation is perhaps the most frequent epigenetic modification in cancer cells. Epigenetic characteristics of cells may be modified by several factors including environmental exposure, certain nutrient deficiencies, radiation, etc. Some of these alterations have been correlated with the formation of aneuploid cells in vivo. A growing body of evidence suggests that aneuploidy is produced and caused by chromosomal instability. We propose and support in this manuscript that not only genetics but also epigenetics, contribute in a major fashion to aneuploid cell formation

La violencia del crimen organizado en México. Una interpretación desde la filosofía

La violencia que se está presentando en México y que suele vincularse con el crimen organizado, se ha convertido en uno de los mayores problemas sociales en el país, sin embargo, tanto su comprensión, análisis, como las propuestas de solución que han sido planteadas desde la esfera gubernamental, han estado monopolizados por lo que aquí se llamará el “léxico científico-utilitarista”, dejando en un sitio muy marginal a otros lenguajes, como el de la propia filosofía. La preponderancia que ha adquirido dicho “léxico científico-utilitarista” estaría conduciendo a que comprendamos y experimentemos nuestra violencia con y desde las posibilidades de apertura del mundo ínsitas en ese lenguaje específico; por ello, resulta oportuno cuestionarnos si este dominio lingüístico de la mirada científica ha tenido efectos de carácter ontológico sobre el fenómeno de la violencia, y de ser así, en qué ha repercutido ello. En esta investigación se recurre a pensadores como Martin Heidegger, Ernst Tugendhat, Hans-Georg Gadamer, Xavier Zubiri, Martha Nussbaum, Richard Rorty y Antonio González, para intentar explicitar las implicaciones comprensivas –y ontológicas, por ende-, así como éticas, de la hegemonía del “léxico científico-utilitarista” en nuestras interpretaciones más comunes y aceptadas de la violencia del crimen organizado.ITESO, A. C

The Epigenetic Origin of Aneuploidy

Theodore Boveri, eminent German pathologist, observed aneuploidy in cancer cells more than a century ago and suggested that cancer cells derived from a single progenitor cell that acquires the potential for uncontrolled continuous proliferation. Currently, it is well known that aneuploidy is observed in virtually all cancers. Gain and loss of chromosomal material in neoplastic cells is considered to be a process of diversification that leads to survival of the fittest clones. According to Darwin’s theory of evolution, the environment determines the grounds upon which selection takes place and the genetic characteristics necessary for better adaptation. This concept can be applied to the carcinogenesis process, connecting the ability of cancer cells to adapt to different environments and to resist chemotherapy, genomic instability being the driving force of tumor development and progression. What causes this genome instability? Mutations have been recognized for a long time as the major source of genome instability in cancer cells. Nevertheless, an alternative hypothesis suggests that aneuploidy is a primary cause of genome instability rather than solely a simple consequence of the malignant transformation process. Whether genome instability results from mutations or from aneuploidy is not a matter of discussion in this review. It is most likely both phenomena are intimately related; however, we will focus on the mechanisms involved in aneuploidy formation and more specifically on the epigenetic origin of aneuploid cells. Epigenetic inheritance is defined as cellular information—other than the DNA sequence itself—that is heritable during cell division. DNA methylation and histone modifications comprise two of the main epigenetic modifications that are important for many physiological and pathological conditions, including cancer. Aberrant DNA methylation is the most common molecular cancer-cell lesion, even more frequent than gene mutations; tumor suppressor gene silencing by CpG island promoter hypermethylation is perhaps the most frequent epigenetic modification in cancer cells. Epigenetic characteristics of cells may be modified by several factors including environmental exposure, certain nutrient deficiencies, radiation, etc. Some of these alterations have been correlated with the formation of aneuploid cells in vivo. A growing body of evidence suggests that aneuploidy is produced and caused by chromosomal instability. We propose and support in this manuscript that not only genetics but also epigenetics, contribute in a major fashion to aneuploid cell formation

Topografía de la densidad mineral osea: Método de estudio "in vivo" de la cabeza femoral humana mediante TAC

Presentamos un método, no descrito anteriormente, que permite obtener un mapa muy preciso de la distribución topográfica de la densidad mineral ósea relativa de cualquier parte del esqueleto, en el sujeto vivo, a partir de una imagen TAC convencional. El método se basa en la medición directa de los niveles de gris de la imagen TAC, los cuales guardan una relación de linealidad con las Unidades Honsfield, de manera que la densidad óptica de un punto concreto se correlaciona con la densidad ósea del mismo. En nuestro estudio lo hemos aplicado a la cabeza femoral humana, obteniendo la imagen topográfica tridimensional de sus densidades óseas.We describe a new method to obtain an accurate mapping of the bone mineral density which can be applied to any area of the human skeleton in a live subject using conventional CT scan imaging. The method involves direct measurement of grey colour intensity from the CT image. The colour intensity maintains a direct relationship with the Honsfield Units, therefore the optic density of a given area is related to the bone density. In our study this method has been applied to the human femoral head to obtain a three-dimensional topography of the bone density