954 research outputs found
The Polarization and the Recombination Mechanism
We use the recombination and the Thomas Precession Model to obtain a
prediction for the polarization in the
reaction. We study the effect of the recombination function on the
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
Calorimetric and acoustic study of binary mixtures containing an isomeric chlorobutane and butyl ethyl ether or methyl tert-butyl ether
Densities and speeds of sound in the temperature range 283.15-313.15 K have been measured for the binary mixtures formed by an isomeric chlorobutane (1-chlorobutane, 2-chlorobutane, 1-chloro-2-methylpropane, or 2-chloro-2-methylpropane) and butyl ethyl ether or methyl tert-butyl ether. Excess isentropic compressibilities were calculated from the experimental data. Excess enthalpies at T = 298.15 K are also included for the same binary mixtures. All these properties provide an insight into the nature of interactions operating on the present systems. Finally, the Prigogine-Flory-Patterson theory has been used to analyze the H E results and to estimate the isentropic compressibility values of the mixtures at T = 298.15 K
Regional initiative for the evaluation of Queen Conch (Strombus gigas) exploitation under an historical perspective
Knowledge, Learning and Development: the Challenge of Small and Medium Enterprises to Global Competition
Estudio longitudinal sobre redes sociales como método didáctico
This article gathers the perceptions of students on social
networks, as a didactic method, with the aim of searching
and designing didactic strategies to adapt the contents and
methodology to the new technological context. The parti-
cipants were university students of Early Childhood and Pri-
mary Education in 2013-2014 and 2016-2017. A longitudinal
study was conducted with a descriptive, non-experimental
methodology and the semi-structured questionnaire used
was validated through factorial and cluster analyses. The
students from both degrees showed a polarization and dis-
persion of opinions about social networks, which could be
related to a more critical attitude toward their advantages
and disadvantages.Este artículo recoge las percepciones de los estudiantes sobre
las redes sociales como método didáctico, con el propósito
de investigar y diseñar estrategias didácticas para adaptar los
contenidos y la metodología al nuevo contexto tecnológico.
Los participantes fueron estudiantes universitarios del pro-
grama de Educación primaria y de la temprana infancia de
los periodos 2013-2014 y 2016-2017. Se hizo un estudio lon-
gitudinal con una metodología no-experimental, descriptiva
y se validó un cuestionario semi-estructurado a través de aná-
lisis factorial y de grupos. Los estudiantes de ambos periodos
mostraron una polarización y dispersión de opiniones sobre
las redes sociales, lo que podría estar relacionado con una
actitud más crítica con respecto a sus ventajas y desventajas
TLR-Mediated Host Immune Response to Parasitic Infectious Diseases
Toll-like receptors (TLRs) are important for the host immune response to a variety of pathogens, including bacteria, viruses, fungi, and parasites. These receptors become activated upon recognizing pathogen-associated molecular patterns (PAMPs) and thus initiate the innate immune response to the corresponding pathogen. A key aspect of TLRs is their activation of signaling that leads to cytokine production and an inflammatory response. Additionally, TLRs act as the bridge between innate and acquired immunity, enhancing phagocytosis and the process of killing parasites. We herein focus on how parasites (protozoans and helminths) and their derived products have the capability of stimulating or evading the host response by triggering or inhibiting TLR activation. Parasites often develop successful survival strategies that imply interference with the host immune response. Accordingly, many of these organisms have molecules that modulate inflammation and other aspects of host immunity. Taking advantage of such mechanisms, there are some anti-inflammatory therapies based on human infection with helminths. Helminths and protozoans influence the activity of various TLRs, especially TLR2, TLR4, and TLR9. A better understanding of the role of TLRs and their parasite-derived ligands should certainly provide new therapeutic tools for combatting various parasitic and inflammatory diseases
Immune Evasion Strategies
Leishmania is the causative protozoan parasite of leishmaniasis. Distinct species provoke localized/diffuse cutaneous leishmaniasis or visceral leishmaniasis. Leishmania parasites have developed diverse strategies to evade the host immune response expressed through various cells, especially macrophages, NK cells, and dendritic cells. Participating in some of these strategies are Leishmania surface molecules, such as lipophosphoglycan (LPG) and protease gp63, which are thus considered virulence factors. LPG has been shown to modulate proinflammatory responses. For example, L. major LPG activates NK cells through toll-like receptor-2 (TLR2), while L. mexicana LPG elicits a differential production of cytokines in human dendritic cells and monocytes. Moreover, L. mexicana LPG activates MAP kinases in macrophages, which in turn enhance proinflammatory cytokine production through TLRs. Additionally, Leishmania exosomes have been found to strongly affect macrophage signaling and functions. Furthermore, proteins secreted by Leishmania promastigotes and amastigotes modulate the production of proinflammatory cytokines in human macrophages. Since Leishmania is an obligate intracellular parasite, its promastigotes utilize several mechanisms to survive and duplicate inside host cells, including the inhibition of apoptosis. It is now clear that MAPK p38, JNK, ERK 1/2, and PI3K/Akt participate in the inhibition of both natural and induced apoptosis of macrophages, neutrophils, and dendritic cells
Trans-splenic puncture during percutaneous nephrolithotomy: Outcome spectrum of the same complication
AbstractPercutaneous nephrolithotomy is an endourologic technique commonly used in the management of nephrolithiasis. However, this procedure is not complication-free. Splenic injury is exceptionally rare with a reported rate of 1% from the total case load. We present herein two cases of splenic puncture during percutaneous nephrolithotomy that illustrate two different outcomes. In the first case, the patient remained asymptomatic and was discharged on her third post-operative day after removing the nephrostomy, without any sign of hemodynamic compromise. In the second case, the patient presented with hemodynamic instability and an abdominal computed tomography scan was done that showed free fluid in the peritoneal cavity. Emergency laparotomy was performed and revealed a deep peripheral laceration (20mm×5mm in length) that required splenectomy. After a thorough review of the existing literature, we could find only 11 other instances of injury to the spleen in which treatment outcomes were reported. Patient hemodynamic status was the main factor in deciding on the type of treatment
Medios de comunicación y derecho a la información en Jalisco 2012
Se presentan los resultados del trabajo de observación al sistema de comunicación política durante las campañas electorales para elegir
gobernador en el estado de Jalisco durante 2012. La observación estuvo compuesta de ocho proyectos de
investigación, los cuales se enfocaron a estudiar distintas
partes del sistema de comunicación política: agenda de los
medios, publicación de encuestas en la prensa local, aparición
de nuevos espacios en el sistema de comunicación,
contenido de los spots propagandísticos, documentación
de las violaciones a la ley electoral, contenidos en comunidades virtuales (páginas de la Internet, Facebook, Twitter
y YouTube), debates entre los candidatos al gobierno de
Jalisco, y cobertura mediática el 1 de julio, el día de las
votaciones.ITESO, A.C
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