A Perspective on Arkansas Basin and Ozark Highland Prehistory

It is, from time to time, valuable to reassess and perhaps shed new light on long-held perspectives. In The \u27Northern Caddoan Area\u27 was not Caddoan, Frank Schambach provides a provocative reinterpretation of the archaeology of the Arkansas Basin and Ozark Highland regions of Oklahoma, Arkansas, and Missouri. While certain comments in this paper have merit and deserve deeper consideration, the central theme and supporting arguments are severely flawed, both from conceptual and data points of view. Schambach\u27s central argument is that there were no Caddoans in the Arkansas Basin and Ozark Highlands north of Spiro. To make this point he asserts that the only Caddoan site north of the Ouachita Mountains is the Brown Mound group at Spiro. All the other sites in the region, including the Craig Mound group at Spiro, are not Caddoan, but are instead a currently undefined Mississippian manifestation. Schambach\u27s scenario goes. something like this: Mississippians moved up the Arkansas River valley in the early,Mississippian Period (presumably in the Harlan Phase, A.O. 850-1250), through western Arkansas to eastern Oklahoma where they displaced the Caddoans living at the Brown Mound group. The Caddoans moved back south to the Ouachita Mountains. The Mississippians, including people of the Plum Bayou culture ... the Spiro phase [A.O. 1250-1450] then built Craig Mound at Spiro while possibly operating a trade system to supply buffalo meat arid hides to the rapidly growing and increasingly protein poor and clothing poor Mississippian populations. . .. to the east. Later, the Mississippians, who were probably ancestral Tunica, retreated back down the Arkansas River to south of Dardenelle, where De Soto encountered them in 1541. The Caddoans then returned to the Spiro area to become the people of the Fort Coffee Phase (A.O. 1450-1500s). This sequence of events is a fascinating reinterpretation of regional culture history, unfortunately it falls flat when confronted by either contemporary theory or the data

THE CYCLICAL NATURE OF POLITICS AND THE U.S. FOOD SYSTEM

Agricultural and Food Policy, Political Economy,

Teaching with Technology to Engage Students and Enhance Learning

Teaching technology effects on student learning in a large lecture introductory statistics course were tested. Findings show in-class personal response systems and on-line homework/quizzes significantly improve student exam scores. We infer proven small class techniques, participating in class and doing homework via technologies, can restore sound pedagogy in larger classes. The experiment was conducted using just one class, but factors usually unaccounted for in assessment research were controlled, especially the instructor and other materials. The technologies investigated here can provide learning benefits to students even in larger courses often criticized for their inability to provide students quality learning experiences.Teaching, technology, statistics, active learning.

Deactivation of TEM-1 beta-Lactamase investigated by isothermal batch and non-isothermal continuous enzyme membrane reactor methods

The thermal deactivation of TEM-1 β-lactamase was examined using two experimental techniques: a series of isothermal batch assays and a single, continuous, non-isothermal assay in an enzyme membrane reactor (EMR). The isothermal batch-mode technique was coupled with the three-state Equilibrium Model of enzyme deactivation, while the results of the EMR experiment were fitted to a four-state molten globule model . The two methods both led to the conclusions that the thermal deactivation of TEM-1 β -lactamase does not follow the Lumry-Eyring model and that the Teq of the enzyme (the point at which active and inactive states are present in equal amounts due to thermodynamic equilibrium) is at least 10 °C from the Tm (melting temperature), contrary to the idea that the true temperature optimum of a biocatalyst is necessarily close to the melting temperature

Lignin-derived thermosetting vinyl ester resins for high performance applications

Vinyl ester (VE) resins are utilized to produce polymer matrix composites for use in a wide range of applications due to possessing relatively high moduli, strengths, and glass transition temperatures while maintaining low weight and cost. VE resins often contain high concentrations of a petroleum-based reactive diluent (RD), such as styrene. Many of the commonly used RDs have been designated as hazardous air pollutants, potential carcinogens, and volatile organic compounds. Renewable VE resins and RDs with similar performance to petroleum-based RDs are desired to potentially mitigate the aforementioned hazards as well as to facilitate the transition from petrochemical feedstocks to bio-based feedstocks. Lignin, which is an abundant renewable resource with a high aromatic content, has the potential to replace petrochemical feedstocks for VE resins and RDs. Lignin is produced in excess of 50 million tons annually as low value fuel for energy recovery, yet has the potential to produce high value chemicals and polymer precursors. In this work, a review of the literature was conducted in order to create multiple lignin-derived bio-oil mimics that were functionalized and subsequently polymerized to make high performance thermosetting plastics. In addition, lignin-derived compounds were investigated for use as RDs in a VE resin system to potentially reduce or eliminate the need for petrol derived RDs. The thermo-mechanical properties of all plastics were investigated via dynamic mechanical analysis and various structure property relationships are proposed

Using Fluorescence Correlation Spectroscopy to Measure Partial Unfolding of Variants of Cytochrome c

The protein Cytochrome c (Cytc) has been known to be a regulatory on/off switch for apoptosis, or programmed cell death, when unfolded. Using Guanidine Hydrochloride (GuHCl) of different concentrations to denature 3 variants of Zinc Cytc (ZnCytc), the unfolding of this protein can be measured. Measuring is performed through different methods such as single- and dual-focus Fluorescence Correlation Spectroscopy (FCS) and Circular Dichroism (CD). FCS is used to measure the change in lifetime of the protein to determine if the protein has unfolded. The change in lifetime is a characterization of partially unfolded proteins. Data are recorded and analyzed through several different Matlab codes to fully understand the folding code of the protei