Georgia College & State University

About: Georgia College & State University is a education organization based out in Milledgeville, Georgia, United States. It is known for research contribution in the topics: Population & Context (language use). The organization has 950 authors who have published 1591 publications receiving 37027 citations.

Fossil Snakes of the Clarendonian (Late Miocene) Pratt Slide Local Fauna of Nebraska, with the Description of a New Natricine Colubrid

Abstract: The Pratt Slide fossil site of Brown County, Nebraska, has yielded the largest and most diverse Clarendonian North American Land Mammal Age (late Miocene; approximately 10.5-9.5 Ma) snake fauna thus far known. The overall composition of the snake fauna consists of extinct taxa from older Miocene times, temporally isolated taxa, and modern taxa. More specifically, the fauna includes at least two extinct erycine boids, 14 colubrids of which five genera are extinct, and possibly three extant viperid genera. The fossil site yielded additional evidence (three vertebrae) of the unique late Clarendonian erycine Tregophis brevirachis and vertebrae of a new distinctive tiny natricine colubrid. Additional vertebrae of a Paleoheterodon-Heterodon snake(s) further support the suggestions by others that these two xenodontine colubrids are indistinguishable at the vertebral level. Overall, the composition of the Pratt Slide snake fauna provides supportive evidence of a North American late Miocene transition from an archaic to a modern snake fauna with most of the modernization taking place during Clarendonian to Hemphillian time (approximately 10-6 Ma).

Do Economists Recognize an Opportunity Cost When They See One? A Dismal Performance or an Arbitrary Concept?

Abstract: [Author Affiliation]Joel Potter, , , , jmpotter@northgeorgia.eduShane Sanders, , , , sd-sanders@wiu.edu[Acknowledgment]Thank you to Dr. John L. Scott, Dr. Laura Razzolini (Editor), and two anonymous reviewers for helpful comments and suggestions.1. IntroductionIn an influential article, Ferraro and Taylor (2005) ask a large sample of PhD students and economists "a very simple question that tests their understanding of opportunity costs" (p. 1). Here is the question in its entirety:Please Circle the Best Answer to the Following Question:You won a free ticket to see an Eric Clapton concert (which has no resale value). Bob Dylan is performing on the same night and is your next-best alternative activity. Tickets to see Dylan cost $40. On any given day, you would be willing to pay up to $50 to see Dylan. Assume there are no other costs of seeing either performer. Based on this information, what is the opportunity cost of seeing Eric Clapton?A. $0 B. $10 C. $40 D. $50Ferraro and Taylor defend answer B ($10) as correct in the following passage:Given the correct answer was the least popular, we believe it worthwhile to state why $10 is the opportunity cost of seeing Eric Clapton. When you go to the Clapton concert, you forgo the $50 of benefits you would have received from going to the Dylan concert. You also forgo the $40 of costs that you would have incurred by going to the Dylan concert. An avoided benefit is a cost, and an avoided cost is a benefit. (2005, p. 4)Ferraro and Taylor (2005) acknowledge that the question was adapted from p. 4 of Frank and Bernanke's textbook, Principles of Microeconomics (2001). Subsequently, Frank approves of the question's adaptation in the introduction of his popular economics book, The Economic Naturalist (2007b, p. 5), and reaffirms that the uniquely correct answer may be derived via a basic understanding of opportunity cost. The 199 economists who answered the adapted question responded as follows: A. $0 (50 responses); B. $10 (43 responses); C. $40 (51 responses); D. $50 (55 responses).In response to the Ferraro and Taylor study, Becker (2007, p. 14) poses the following open question, "Could it be that graduate textbooks, as in my presentation on the shadow prices of teaching and research, have correctly given up on the introductory economics course idea of an opportunity cost in favor of more useful measures of price?"1 Further, Margolis (2007) states, "But this does not really show that professors of economics have a grossly inadequate grasp of a routine technical term in their discipline, only that Ferraro and Taylor's rather odd question happens to trigger the sort of cognitive mechanism that accounts for illusory responses elsewhere" (p. 104).Challenging the notion that the previous question "is straightforward and should not require great cognitive effort by PhD-level economists" (Ferraro and Taylor 2005, p. 6), we use standard economic assumptions to show that any of the four responses can be defended as correct.2 In light of alternative interpretations, we argue that the question is not an appropriate instrument from which to gauge understanding of economic cost and related concepts. Moreover, we contend that opportunity cost accounting is sufficiently arbitrary to preclude it from reliably indicating one's understanding of marginal analysis. In fairness to Ferraro and Taylor, we suggest several difficulties involved in framing a valid question on opportunity cost.Colander, Gaastra, and Rothschild (2010) present a pedagogical analysis of the "top-down" (e.g., centralized) and "bottom-up" (e.g., decentralized) costs of market restrictions. In so doing, the authors are able to texture the pedagogical analysis of a traditional economic concept. This article seeks the same general end in its treatment of opportunity cost accounting and logic. …

Zotero: harnessing the power of a personal bibliographic manager

Abstract: Zotero is a powerful free personal bibliographic manager (PBM) for writers. Use of a PBM allows the writer to focus on content, rather than the tedious details of formatting citations and references. Zotero 2.0 (http://www.zotero.org) has new features including the ability to synchronize citations with the off-site Zotero server and the ability to collaborate and share with others. An overview on how to use the software and discussion about the strengths and limitations are included.

Recent developments in transcriptional and translational regulation underlying long-term synaptic plasticity and memory.

Abstract: Formation of long-term synaptic plasticity that underlies long-term memory requires new protein synthesis. Years of research has elucidated some of the transcriptional and translational mechanisms that contribute to the production of new proteins. Early research on transcription focused on the transcription factor cAMP-responsive element binding protein. Since then, other transcription factors, such as the Nuclear Receptor 4 family of proteins that play a role in memory formation and maintenance have been identified. In addition, several studies have revealed details of epigenetic mechanisms consisting of new types of chemical alterations of DNA such as hydroxymethylation, and various histone modifications in long-term synaptic plasticity and memory. Our understanding of translational control critical for memory formation began with the identification of molecules that impinge on the 5' and 3' untranslated regions of mRNAs and continued with the appreciation for local translation near synaptic sites. Lately, a role for noncoding RNAs such as microRNAs in regulating translation factors and other molecules critical for memory has been found. This review describes the past research in brief and mainly focuses on the recent work on molecular mechanisms of transcriptional and translational regulation that form the underpinnings of long-term synaptic plasticity and memory.

Critical currents, magnetic relaxation and pinning in NdBa 2 Cu 3 O 7-δ films with BaZrO 3 -generated columnar defects

Abstract: The critical current density Jc and the magnetic relaxation (‘creep’) properties have been studied for a set of NdBa2Cu3O7−δ (NdBCO) films doped with BaZrO3 (BZO) nanoparticles to form columnar defects. The dependence of Jc on the magnitude and orientation of the applied magnetic field Happ (0–6.5 T) and temperature T (5 K–Tc) was investigated. The normalized flux-creep rate S =− dln(J)/dln(t) was determined as a function of T. The current dependence of the effective activation energy Ueff(J) was derived using the formalism developed by Maley. The results are well described by an inverse power law type barrier of the form Ueff(J) ∼ U0(J0/J)μ with fitted values for the pinning energy scale U0 and the glassy exponent μ. When comparing values for these parameters in the BZO-doped samples with those for their undoped control counterparts, the most striking difference is the larger scale of current density J0 in the doped samples (a factor of 2.4 higher), while the other pinning parameters do not differ strongly. In the BZO-doped materials, the pinning energy scale U0 increases with vortex density and J0 decreases, with both following simple power law dependences on the field.