Precise nondivergent analytic formulas for the radiative corrections to the beta energy spectrum in hyperon semileptonic decays over the entire Dalitz plot

Very accurate analytical expressions for the radiative corrections of unpolarized hyperons semileptonic decays of charged and neutral baryons have been obtained in the recent past. Some of these formulas contain logarithmic singularities at the edges of the Dalitz plot for the three- and four-body decays. These singularities are analyzed and integrated analytically to obtain new divergentless formulas for the energy spectrum of the produced beta particle. The new equations contain terms of the order alpha times the momentum transfer, are applicable to any beta decay process and are suitable for a model-independent experimental analysis.Comment: 22 pages, 4 figure

Mujeres, mujeres, mujeres...

Texto sobre las participantes en el curso de español que se llevó a cabo en el ITESO, entre el 30 de junio y el 22 de agosto de 1986, organizado por el ITESO y el Spanish Education for Women.ITESO, A.C

Secreto y monopolio En Venecia: El gremio del vidrio muranés

During the Middle Ages, the Republic of Venice developed a strong monopoly on the art of glass until the 17<sup>th</sup> century. This social and political control over the guild of glassmakers created a new model of guild based on the protection of the secret knowledge and counterintelligence. It was one of the most important causes of the development of the Venetian intelligence service, the most important in Europe in the early Modern Age. This article analyses the Venetian Republic control over the glass secret and how it affected the glassmakers guild in Venice and Murano.<br><br>Durante los siglos centrales de la Edad Media la República de Venecia desarrolló un monopolio sobre el negocio del vidrio que se prolongó hasta mediados del siglo XVII. Este control del arte del vidrio en todos los aspectos provocó que el gremio de los vidrieros de Murano evolucionara legal y socialmente a un modelo específico basado en la protección de la información y en la contrainteligencia, que influyó de forma decisiva en la consolidación de la estructura de espionaje e inteligencia veneciana, la más importante en la baja Edad Media y principios de la Modernidad. Este artículo pretende analizar el control que la República veneciana desarrolló sobre el secreto del vidrio y cómo éste afectó al modelo de gremio desarrollado primero en Venecia y después en Murano

Presentación del tema Semiótica de la Revista Renglones número 19

Presentación del tema central del número 19 de la revista Renglones: Semiótica. Incluye obra fotográfica de Carolina Ramírez, reproducida en blanco y negro.ITESO, A.C

Quevedo, Contreras, Duque de Estrada y sus conceptos del Mediterráneo

El artículo es un análisis de la representación verbal del área del Mediterráneo a principios del siglo XVII en Mundo caduco de Quevedo en contraste con la que ofrece Duque de Estrada y Contreras en sus autobiografías. El estudio parte de las teorías postuladas, entre otros, por Lefebvre y Soja que suponen que el espacio es una construcción social con un significado político y estratégico que depende de las luchas por el poder y que su representación en textos escritos reproducen estas dialécticas filtradas por la percepción personal del autor. En su descripción Quevedo impone un ideario político y personal que moraliza y fija los enclaves socio-geográficos mientras que los testimonios de Contreras y Duque de Estrada ofrecen una visión más dinámica del Mediterráneo como una zona ambigua plagada de conflictos y de intercambios comerciales, humanos y culturales. This article analyses the verbal representation of the Mediterranean area at the beginning of the Seventeenth Century in Mundo caduco by Quevedo in contrast with the one offered by Duque de Estrada and Contreras in their respective autobiographies. The theoretical background is the postulates of Lefebvre and Soja, for whom space is a social construction with a strategic and political meaning, which depends on power struggles. Verbal representations of space reproduce this dialectic in addition to the subjective authorial perception. In his description Quevedo imposes his political and personal agenda, which moralises and fixates the social-geographical places while Contreras and Duque de Estrada’s testimonies offer a dynamic vision of the Mediterranean as an ambiguous zone filled with conflicts and with commercial, human and cultural exchanges

CXCL12-induced neurotoxicity critically depends on NMDA receptor-gated and L-type Ca2+ channels upstream of p38 MAPK.

BackgroundThe chemokine receptor CXCR4 (CD184) and its natural ligand CXCL12 contribute to many physiological processes, including decisions about cell death and survival in the central nervous system. In addition, CXCR4 is a co-receptor for human immunodeficiency virus (HIV)-1 and mediates the neurotoxicity of the viral envelope protein gp120. However, we previously observed that CXCL12 also causes toxicity in cerebrocortical neurons but the cellular mechanism remained incompletely defined.MethodsPrimary neuronal-glial cerebrocortical cell cultures from rat were exposed to a neurotoxicity-inducing CXCL12 concentration for different times and the activity of the stress-associated mitogen-activated protein kinase p38 (p38 MAPK) was assessed using an in vitro kinase assay. Neurotoxicity of CXCL12 and cellular localization of p38 MAPK was analyzed by immunofluorescence microscopy. Pharmacological inhibition of NMDA-type glutamate receptor-gated ion channels (NMDAR) of L-type Ca2+ channels was employed during 12- and 24-h exposure to neurotoxic amounts of CXCL12 to study the effects on active p38 MAPK and neuronal survival by Western blotting and microscopy, respectively. Neurotoxicity of CXCL12 was also assessed during pharmacological inhibition of p38 MAPK.ResultsHere, we show that a neurotoxic amount of CXCL12 triggers a significant increase of endogenous p38 MAPK activity in cerebrocortical cells. Immunofluorescence and Western blotting experiments with mixed neuronal-glial and neuron-depleted glial cerebrocortical cells revealed that the majority of active/phosphorylated p38 MAPK was located in neurons. Blockade of NMDAR-gated ion channels or L-type Ca2+ channels both abrogated an increase of active p38 MAPK and toxicity of CXCL12 in cerebrocortical neurons. Inhibition of L-type Ca2+ channels with nimodipine kept the active kinase at levels not significantly different from baseline while blocking NMDAR with MK-801 strongly reduced phosphorylated p38 MAPK below baseline. Finally, we confirmed that directly blocking p38 MAPK also abrogated neurotoxicity of CXCL12.ConclusionsOur findings link CXCL12-induced neuronal death to the regulation of NMDAR-gated ion channels and L-type Ca2+ channels upstream of p38 MAPK activation

Short Photoluminescence Lifetimes Linked to Crystallite Dimensions, Connectivity, and Perovskite Crystal Phases

Time-correlated single photon counting has been conducted to gain further insights into the short photoluminescence lifetimes (nanosecond) of lead iodide perovskite (MAPbI3) thin films (~100 nm). We analyze three different morphologies, compact layer, isolated island, and connected large grain films, from 14 to 300 K using a laser excitation power of 370 nJ/cm2. Lifetime fittings from the Generalized Berberan-Santos decay model range from 0.5 to 6.5 ns, pointing to quasi-direct bandgap emission despite the three different sample strains. The high energy band emission for the isolated-island morphology shows fast recombination rate centers up to 4.8 ns-1, compared to the less than 2 ns-1for the other two morphologies, similar to that expected in a good quality single crystal of MAPbI3. Low-temperature measurements on samples reflect a huge oscillator strength in this material where the free exciton recombination dominates, explaining the fast lifetimes, the low thermal excitation, and the thermal escape obtained. © 2022 American Chemical Society. All rights reserved

Decision making and model M. Mishel. Accept or not accept replacement surgery knee prosthetic

Introducción: La artroplastia total de rodilla (PTR) es eficaz en el alivio del dolor y la función en los casos de artrosis de rodilla (AR) grave. Representa un problema de salud pública por su prevalencia. A pesar de los resultados clínicos obtenidos con la PTR, diversos estudios refieren que entre un 14-30% de pacientes se muestran insatisfechos con el resultado, al no alcanzar los beneficios esperados, lo que conlleva que otros desestimen el tratamiento quirúrgico. El modelo de cuidados de M. Mishel pertenece al paradigma de la transformación, parte de la teoría social crítica e incorpora principios de la teoría del caos para elaborar su teoría de la incertidumbre; la enfermedad crónica desencadena un desequilibrio y las personas que la experimentan pueden incorporar esta incertidumbre para adquirir un nuevo sentido de la vida