Internet, herramienta de apoyo a los egresados de la Universidad de Talca

145 p.El estudio pretende identificar los servicios que ofrece Internet para utilizarlos en beneficio de los egresados de la Universidad de Talca, por medio de la creación de un prototipo del servicio que sirva como base para su posterior realización. En el desarrollo del proyecto, se realizo una investigación exploratoria como primer paso, para determinar el estado del arte en la educación superior vía Internet, y una investigación descriptiva dirigida a los egresados y alumnos de ultimo ano, correspondientes al primer semestre de 1997, con el fin de determinar sus hábitos de use de Internet, su demanda por el desarrollo de servicios vía Internet y cuales serian las características de estos servicios. Los servicios identificados fueron el resultado de estas investigaciones. Con los que una vez definidos, se procedió a evaluarlos estratégicamente, donde se puso a prueba la validez, coherencia, factibilidad, vulnerabilidad, adecuación y recompensas potenciales que pudiera presentar cada uno de ellos. En esta etapa se descubrió el servicio que presenta características que permiten aprovechar las oportunidades reinantes en el entorno y donde la universidad posee las capacidades para llevarlo a cabo, que lleva el nombre de "Centro de Apuntes de la Universidad de Talca", donde se recopilan documentos, pruebas, tesis, seminarios y todo tipo de escritos que tengan su origen en la Universidad de Talca, tanto de alumnos como del profesorado. Este Centro de Apuntes irá dirigido en una primera etapa a la comunidad universitaria, sin exclusión de ninguna carrera

Megadrought and Megadeath in 16th Century Mexico

The native population collapse in 16th century Mexico was a demographic catastrophe with one of the highest death rates in history. Recently developed tree-ring evidence has allowed the levels of precipitation to be reconstructed for north central Mexico, adding to the growing body of epidemiologic evidence and indicating that the 1545 and 1576 epidemics of cocoliztli (Nahuatl for "pest”) were indigenous hemorrhagic fevers transmitted by rodent hosts and aggravated by extreme drought conditions

Influenza and Pneumonia Mortality in 66 Large Cities in the United States in Years Surrounding the 1918 Pandemic

The 1918 influenza pandemic was a major epidemiological event of the twentieth century resulting in at least twenty million deaths worldwide; however, despite its historical, epidemiological, and biological relevance, it remains poorly understood. Here we examine the relationship between annual pneumonia and influenza death rates in the pre-pandemic (1910–17) and pandemic (1918–20) periods and the scaling of mortality with latitude, longitude and population size, using data from 66 large cities of the United States. The mean pre-pandemic pneumonia death rates were highly associated with pneumonia death rates during the pandemic period (Spearman r = 0.64–0.72; P,0.001). By contrast, there was a weak correlation between pre-pandemic and pandemic influenza mortality rates. Pneumonia mortality rates partially explained influenza mortality rates in 1918 (r = 0.34, P = 0.005) but not during any other year. Pneumonia death counts followed a linear relationship with population size in all study years, suggesting that pneumonia death rates were homogeneous across the range of population sizes studied. By contrast, influenza death counts followed a power law relationship with a scaling exponent of ,0.81 (95%CI: 0.71, 0.91) in 1918, suggesting that smaller cities experienced worst outcomes during the pandemic. A linear relationship was observed for all other years. Our study suggests that mortality associated with the 1918–20 influenza pandemic was in part predetermined by pre-pandemic pneumonia death rates in 66 large US cities, perhaps through the impact of the physical and social structure of each city. Smaller cities suffered a disproportionately high per capita influenza mortality burden than larger ones in 1918, while city size did not affect pneumonia mortality rates in the pre-pandemic and pandemic periods

Closeness to one\u27s father and a sense of loneliness among Hispanic and Caucasian college adult males

The purpose of this study was to examine the relationship between the closeness to one\u27s father and a sense of loneliness among Hispanic and Caucasian college adult males. In essence, this study was an attempt to gain a greater understanding of the connection, if any, between the presence of a “father wound” and degree of loneliness that men report as adults. Results indicated that a significant relationship does not appear to exist between the closeness to one\u27s father and a sense of loneliness study participants

Redox properties of nanostructured lanthanide-doped ceria spheres prepared by microwave assisted hydrothermal homogeneous co-precipitation

This work has been supported by: the Brazilian Synchrotron Light Laboratory (LNLS, Brazil), under proposals D04BXAFS1-13435 and D12A-XRD1-13437. AgenciaNacional de PromociónCientífica y Tecnológica (Argentina, PICT 2012-1506).In this work, nanostructured LnxCe1−xO2−δ (Ln: Gd and Pr; x = 0.1 and 0.2) spheres were synthesized by microwave assisted hydrothermal homogeneous co-precipitation and their properties were characterized by synchrotron radiation XRD, X-ray absorption near-edge spectroscopy (XANES) and scanning and high-resolution electron microscopy (SEM and HRTEM). In situ XRD and XANES experiments were carried out under reducing and oxidizing conditions in order to investigate the redox behaviour of these materials. The nanostructured mixed oxide spheres were found to have a cubic crystal structure (Fm3m space group). The spheres were composed of nanoparticles with an average crystallite size of about 10 nm. The Ln0.1Ce0.9O2−δ compositions exhibited the highest specific surface area (∼60 m2 g−1). In situ XRD experiments showed an increase in lattice parameters upon reduction, which was attributed to the reduction of Ce4+ and Pr4+ cations to Ce3+ and Pr3+, which have larger radii, and to the associated increase in VO concentration. This increase in lattice parameters was considerably more pronounced for PrDC than GDC, and was explained by the considerably larger change in ionic radius for Pr upon reduction. XANES absorption experiments at the Ce and Pr L3-edge showed that the changes observed upon reduction of the Pr-containing samples resulted mostly from the formation of Pr3+ rather than Ce3+, and supported the previously reported proposal that Pr3+ has a stabilizing effect on Ce4+.PostprintPeer reviewe

Drought and Epidemic Typhus, Central Mexico, 1655–1918

Epidemic typhus is an infectious disease caused by the bacterium Rickettsia prowazekii and transmitted by body lice (Pediculus humanus corporis). This disease occurs where conditions are crowded and unsanitary. This disease accompanied war, famine, and poverty for centuries. Historical and proxy climate data indicate that drought was a major factor in the development of typhus epidemics in Mexico during 1655–1918. Evidence was found for 22 large typhus epidemics in central Mexico, and tree-ring chronologies were used to reconstruct moisture levels over central Mexico for the past 500 years. Below-average tree growth, reconstructed drought, and low crop yields occurred during 19 of these 22 typhus epidemics. Historical documents describe how drought created large numbers of environmental refugees that fled the famine-stricken countryside for food relief in towns. These refugees often ended up in improvised shelters in which crowding encouraged conditions necessary for spread of typhus

Latitude and longitude coordinates, population size, and mean baseline pneumonia and influenza death rates for 66 large US reporting cities (1910–1920) with 100, 000 or more inhabitants [10].

<p>Latitude and longitude coordinates, population size, and mean baseline pneumonia and influenza death rates for 66 large US reporting cities (1910–1920) with 100, 000 or more inhabitants <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0023467#pone.0023467-Bureau1" target="_blank">[10]</a>.</p