People's Democratic Republic of Ralandia Two Case Studies

The following case studies were designed to promote class discussion on economic policy in developing countries. They are problem solving cases, self-contained, and do not require any additional data. There are three components: Ralandia (A), (B), and (C). Ralandai is a fictitious country located on the southeastern coast of Africa. Ralandia (A) gives an overview of the country, and is not in itself a case study. Ralandia (A) together with Ralandia (B) make up the case on Agricultural Policy; and Ralandia (A) together with Ralandia (C) make up the case on Macroeconomic Policy. In approaching the cases, the reader should keep in mind the following questions: what are the problems that exist; what are the factors which affect why certain policies success and others fail; what is the effect of politics on economic policy; and what are the economic implications of political acts?Center for Research on Economic Development, University of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/100964/1/ECON408.pd

Analysis of Diffusion of Ras2 in Saccharomyces cerevisiae Using Fluorescence Recovery after Photobleaching

Binding, lateral diffusion and exchange are fundamental dynamic processes involved in protein association with cellular membranes. In this study, we developed numerical simulations of lateral diffusion and exchange of fluorophores in membranes with arbitrary bleach geometry and exchange of the membrane localized fluorophore with the cytosol during Fluorescence Recovery after Photobleaching (FRAP) experiments. The model simulations were used to design FRAP experiments with varying bleach region sizes on plasma-membrane localized wild type GFP-Ras2 with a dual lipid anchor and mutant GFP-Ras2C318S with a single lipid anchor in live yeast cells to investigate diffusional mobility and the presence of any exchange processes operating in the time scale of our experiments. Model parameters estimated using data from FRAP experiments with a 1 micron x 1 micron bleach region-of-interest (ROI) and a 0.5 micron x 0.5 micron bleach ROI showed that GFP-Ras2, single or dual lipid modified, diffuses as single species with no evidence of exchange with a cytoplasmic pool. This is the first report of Ras2 mobility in yeast plasma membrane. The methods developed in this study are generally applicable for studying diffusion and exchange of membrane associated fluorophores using FRAP on commercial confocal laser scanning microscopes.Comment: Accepted for publication in Physical Biology (2010). 28 pages, 7 figures, 3 table

Effect of Limb Lengthening on Internodal Length and Conduction Velocity of Peripheral Nerve

The influences of axon diameter, myelin thickness, and internodal length on the velocity of conduction of peripheral nerve action potentials are unclear. Previous studies have demonstrated a strong dependence of conduction velocity on internodal length. However, a theoretical analysis has suggested that this relationship may be lost above a nodal separation of ∼0.6 mm. Here we measured nerve conduction velocities in a rabbit model of limb lengthening that produced compensatory increases in peripheral nerve growth. Divided tibial bones in one hindlimb were gradually lengthened at 0.7 mm per day using an external frame attached to the bone. This was associated with a significant increase (33%) of internodal length (0.95–1.3 mm) in axons of the tibial nerve that varied in proportion to the mechanical strain in the nerve of the lengthened limb. Axonal diameter, myelin thickness, and g-ratios were not significantly altered by limb lengthening. Despite the substantial increase in internodal length, no significant change was detected in conduction velocity (∼43 m/s) measured either in vivo or in isolated tibial nerves. The results demonstrate that the internode remains plastic in the adult but that increases in internodal length of myelinated adult nerve axons do not result in either deficiency or proportionate increases in their conduction velocity and support the view that the internodal lengths of nerves reach a plateau beyond which their conduction velocities are no longer sensitive to increases in internodal length

Self-affirmation theory in educational contexts

Self-affirmation, operationalized as value-affirmation interventions, can have long-term beneficial effects on the academic performance and trajectories of members of negatively stereotyped groups, thus reducing achievement gaps. Yet, there is significant heterogeneity in the effectiveness of value affirmations, and we do not yet have a clear understanding of why. In this introduction to the special issue, we review the literature on self-affirmation theory in educational contexts, providing overviews of the heterogeneity in the effectiveness of affirmation interventions, the methods of implementation, potential moderators, and underling processes. We identify several questions that are important for researchers to address, the answers to which would progress the field towards being able to more confidently implement value-affirmations in contexts in which, and/or for groups for whom, they are most likely to produce benefits. We then introduce the articles included in this special issue, which showcase several of the latest theoretical and empirical advances to self-affirmation theory in educational contexts

Importance of continued activation of thrombin reflected by fibrinopeptide A to the efficacy of thrombolysis

Factors responsible for initial success or failure of coronary thrombolysis and persistent recanalization or early reocclusion have not been thoroughly elucidated. Both adequate initial clot lysis and preclusion of rethrombosis are required. Failure may reflect clot lysis followed immediately or somewhat later by rethrombosis. To determine whether differences in the intensity and persistence of the activation of thrombin are determinants of success or failure of recanalization, plasma fibrinopeptide A, a fibrinogen product liberated by thrombin, was serially assayed in 19 patients treated with intravenous streptokinase. In patients exhibiting recanalization (n = 9), plasma fibrinopeptide A decreased after administration of streptokinase but before administration of heparin. In patients without initially apparent recanalization, fibrinopeptide A increased, suggesting ongoing thrombosis, and subsequently decreased promptly after heparin. In patients with initial recanalization followed by overt reocclusion the pattern was different. Despite recanalization, fibrinopeptide A continued to rise markedly. Elevations persisted despite administration of heparin. Thus, inhibition of activation of thrombin is associated with successful recanalization. Conversely, persistent activation of thrombin may be a predisposing factor to both apparent initial failure of recanalization and nvprt early reocclusion

Inhibition of Respiration by Nitric Oxide Induces a Mycobacterium tuberculosis Dormancy Program

An estimated two billion persons are latently infected with Mycobacterium tuberculosis. The host factors that initiate and maintain this latent state and the mechanisms by which M. tuberculosis survives within latent lesions are compelling but unanswered questions. One such host factor may be nitric oxide (NO), a product of activated macrophages that exhibits antimycobacterial properties. Evidence for the possible significance of NO comes from murine models of tuberculosis showing progressive infection in animals unable to produce the inducible isoform of NO synthase and in animals treated with a NO synthase inhibitor. Here, we show that O2 and low, nontoxic concentrations of NO competitively modulate the expression of a 48-gene regulon, which is expressed in vivo and prepares bacilli for survival during long periods of in vitro dormancy. NO was found to reversibly inhibit aerobic respiration and growth. A heme-containing enzyme, possibly the terminal oxidase in the respiratory pathway, likely senses and integrates NO and O2 levels and signals the regulon. These data lead to a model postulating that, within granulomas, inhibition of respiration by NO production and O2 limitation constrains M. tuberculosis replication rates in persons with latent tuberculosis

The Ursinus Weekly, June 7, 1907

Baccalaureate sermon • Alumni oration • Junior oratorical contest • Class Day exercises • Commencement day • Editorial: The seniors; Vacation • Society notes • Personals • Donation to Library • Alumni • Charmidean banquet • Spiritual conference • Literary Supplement: Farewell song to the Class of 1907; The power of music; Uses of literature; The heredity of the twentieth century; Greater love hath no man; The history and plan of agricultural education; Jerry; A plea for the better management of railroadshttps://digitalcommons.ursinus.edu/weekly/2948/thumbnail.jp