Broadcasting and The Challenge of The 1970\u27s

The weather outside NBC\u27S Chicago studios was rainy and miserable that day in 1932

An Approach to Communication

A Practical Definition Man feels an insatiable desire to communicate. In fact, scientists tell us that better than 70 per cent of our active hours are spent in communicating

A Central American Success Story: Innovation in International Distance Education

Based on actual workshop experiences, faculty at the Honduran Zamorano University in Central America created an effective, size-neutral, world-class distance education (e-learning) program for serving learners throughout Latin America through online and distance learning technology. The program is known as PAC @ D (Programa de Aprendizaje Continuo a Distancia or Life Long Learning Program at a Distance). It is administered by Zamorano’s global center for distance learning. The establishment of PAC @ D in 2010 was preceded by workshop efforts begun in 2004 by the authors. The workshop efforts focused on bridging the cultural uniqueness of educational programs in Latin America and the United States. The goal was to assist local faculty and staff at Zamorano University to build their own digital platform effectively and extend academic and outreach programs through that digital platform. The use of online and distance learning technologies can help extend intellectual capital beyond the limits of the physical campus in fulfilling the teaching, outreach/extension, and, to a limited extent, research missions. However, as we shall see in this professional paper, distance learning is more than turning on the technology with a click and a keystroke. At Zamorano, the development of PAC @ D required many hours of a full range of pedagogical and technological training, spread over 18 months. This professional development paper provides the rationale for PAC @ D, outlines its development, and provides suggestions for enhancing the educational experiences of distance learners

Eph-Dependent Tyrosine Phosphorylation of Ephexin1 Modulates Growth Cone Collapse

SummaryEphs regulate growth cone repulsion, a process controlled by the actin cytoskeleton. The guanine nucleotide exchange factor (GEF) ephexin1 interacts with EphA4 and has been suggested to mediate the effect of EphA on the activity of Rho GTPases, key regulators of the cytoskeleton and axon guidance. Using cultured ephexin1−/− mouse neurons and RNA interference in the chick, we report that ephexin1 is required for normal axon outgrowth and ephrin-dependent axon repulsion. Ephexin1 becomes tyrosine phosphorylated in response to EphA signaling in neurons, and this phosphorylation event is required for growth cone collapse. Tyrosine phosphorylation of ephexin1 enhances ephexin1’s GEF activity toward RhoA while not altering its activity toward Rac1 or Cdc42, thus changing the balance of GTPase activities. These findings reveal that ephexin1 plays a role in axon guidance and is regulated by a switch mechanism that is specifically tailored to control Eph-mediated growth cone collapse

African tropical rainforest net carbon dioxide fluxes in the twentieth century

The African humid tropical biome constitutes the second largest rainforest region, significantly impacts global carbon cycling and climate, and has undergone major changes in functioning owing to climate and land-use change over the past century. We assess changes and trends in CO2 fluxes from 1901 to 2010 using nine land surface models forced with common driving data, and depict the inter-model variability as the uncertainty in fluxes. The biome is estimated to be a natural (no disturbance) net carbon sink (−0.02 kg C m−2 yr−1 or −0.04 Pg C yr−1, p < 0.05) with increasing strength fourfold in the second half of the century. The models were in close agreement on net CO2 flux at the beginning of the century (σ1901 = 0.02 kg C m−2 yr−1), but diverged exponentially throughout the century (σ2010 = 0.03 kg C m−2 yr−1). The increasing uncertainty is due to differences in sensitivity to increasing atmospheric CO2, but not increasing water stress, despite a decrease in precipitation and increase in air temperature. However, the largest uncertainties were associated with the most extreme drought events of the century. These results highlight the need to constrain modelled CO2 fluxes with increasing atmospheric CO2 concentrations and extreme climatic events, as the uncertainties will only amplify in the next century

Standards of beauty: considering the lives of W. A. Poucher

This article considers the complex identity of W. A. Poucher, acclaimed landscape photographer, regional guidebook writer, and perfumer-cosmetician. Taking narrative form, it couples recent disciplinary experiments with the writing of geography and writing of biography. As an exercise in historical geography, the article is concerned with popular topographical culture in mid-twentieth-century Britain, and, gendered subjectivities emergent in the modern world. By considering different aspects of one man’s life-world, an investigative quest is undertaken, one encompassing beauty standards (for attractiveness and ordinariness, landscape scenery and the human body), cultural categories (popular and picturesque, commercial and conservative), sensibilities (camp and queer, dandyism and double-ness), and social values or vices (attributed to surfaces and depths, atmospheres and appearances). The life in question comes to be known according to the sense economies and aesthetics of desirable things, including the miniature camera, pictorial guidebooks, shapely mountains, makeup, cosmetics and fragrances, flash cars, evening television, and weekend golf. W. A. Poucher is ever present as the central subject of geo-biographical inquiries, although any temptation to conclusively place his person is resisted