Place names in the southwest counties of Missouri

Counties: Barton, Cedar, Dade, Greene, Jasper, Lawrence, Newton, and Polk"This thesis is a record of a careful research into the origin of the place-names in eight of the counties in the southwest part of Missouri. These counties are Barton, Cedar, Dade, Greene, Jasper, Lawrence, Newton, and Polk. These counties lie along the northwest slope of the Ozark highlands, whose topography is marked by rolling hills and fertile valleys. Along the valleys are rapidly flowing streams, which furnished ample water power for the grist mills of the pioneers. A comparison of the number of water-mills in these counties with the number in the northern counties shows a significant variation in the topography of the two groups of counties. The abundance of water for the little farms and the economic advantages of the mills, which often became the nuclei of villages, rendered great service to the pioneers, who were turning an untamed wilderness into homes and villages..."--Page 1

A New and Unusual Pathway for the Reaction of Neocarzinostatin Chromophore with Thiols. Revised Structure of the Protein-Directed Thiol Adduct

Neocarzinostatin (holo-NCS) is an antitumor antibiotic comprising a nonprotein chromophore component (1) and a 113- amino acid carrier protein (apo-NCS). Goldberg and coworkers first demonstrated that the reaction of the isolated chromophore (1) with thiols in the presence of double-stranded DNA leads to DNA cleavage by a free-radical mechanism. The pathway shown in Scheme 1 was later proposed to account for this activity, a proposal that is now supported by a considerable body of evidence. In 1992, Saito and co-workers showed that the reaction of holo-NCS with small thiols, such as β-mercaptoethanol (BME), takes a different course, to form a product that is formally a 1:1:1 adduct of thiol, 1, and water. Structure 2 was proposed for this adduct, along with the mechanistic pathway shown in Scheme 2. Complicating the analysis was the fact that 2 was an inseparable mixture of two components, present in equal parts

An Opportunity Cost Model of Subjective Effort and Task Performance

Why does performing certain tasks cause the aversive experience of mental effort and concomitant deterioration in task performance? One explanation posits a physical resource that is depleted over time. We propose an alternative explanation that centers on mental representations of the costs and benefits associated with task performance. Specifically, certain computational mechanisms, especially those associated with executive function, can be deployed for only a limited number of simultaneous tasks at any given moment. Consequently, the deployment of these computational mechanisms carries an opportunity cost – that is, the next-best use to which these systems might be put. We argue that the phenomenology of effort can be understood as the felt output of these cost/benefit computations. In turn, the subjective experience of effort motivates reduced deployment of these computational mechanisms in the service of the present task. These opportunity cost representations, then, together with other cost/benefit calculations, determine effort expended and, everything else equal, result in performance reductions. In making our case for this position, we review alternative explanations for both the phenomenology of effort associated with these tasks and for performance reductions over time. Likewise, we review the broad range of relevant empirical results from across sub-disciplines, especially psychology and neuroscience. We hope that our proposal will help to build links among the diverse fields that have been addressing similar questions from different perspectives, and we emphasize ways in which alternative models might be empirically distinguished

The Spitzer c2d Survey of Nearby Dense Cores. V. Discovery of a VeLLO in the "Starless" Dense Core L328

This paper reports the discovery of a Very Low Luminosity Object (VeLLO) in the "starless" dense core L328, using the Spitzer Space Telescope and ground based observations from near-infrared to millimeter wavelengths. The Spitzer 8 micron image indicates that L328 consists of three subcores of which the smallest one may harbor a source, L328-IRS while two other subcores remain starless. L328-IRS is a Class 0 protostar according to its bolometric temperature (44 K) and the high fraction ~72 % of its luminosity emitted at sub-millimeter wavelengths. Its inferred "internal luminosity" (0.04 - 0.06 Lsun) using a radiative transfer model under the most plausible assumption of its distance as 200 pc is much fainter than for a typical protostar, and even fainter than other VeLLOs studied previously. Note, however, that its inferred luminosity may be uncertain by a factor of 2-3 if we consider two extreme values of the distance of L328-IRS (125 or 310 pc). Low angular resolution observations of CO do not show any clear evidence of a molecular outflow activity. But broad line widths toward L328, and Spitzer and near-infrared images showing nebulosity possibly tracing an outflow cavity, strongly suggest the existence of outflow activity. Provided that an envelope of at most ~0.1 Msunis the only mass accretion reservoir for L328-IRS, and the star formation efficiency is close to the canonical value ~30%, L328-IRS has not yet accreted more than 0.05 Msun. At the assumed distance of 200 pc, L328-IRS is destined to be a brown dwarf.Comment: 29 pages, 8 figures, 1 table, to be published in Astrophysical Journa

Nonabelian D-branes and Noncommutative Geometry

We discuss the nonabelian world-volume action which governs the dynamics of N coincident Dp-branes. In this theory, the branes' transverse displacements are described by matrix-valued scalar fields, and so this is a natural physical framework for the appearance of noncommutative geometry. One example is the dielectric effect by which Dp-branes may be polarized into a noncommutative geometry by external fields. Another example is the appearance of noncommutative geometries in the description of intersecting D-branes of differing dimensions, such as D-strings ending on a D3- or D5-brane. We also describe the related physics of giant gravitons.Comment: 21 pages, Latex, ref. adde

An analytical method for total heavy metal complexing agents in water and its application to water quality studies

The principle research accomplishment on this project was the development of several methods of analysis for low levels of complexing agents, particularly chelating agents. These species are very important in water quality. It is only very recently that their importance has become very apparent in areas such as heavy metal transport, algal growth, and toxicity of heavy metals. The first method developed, was an atomic absorption analysis of strong heavy metal chelating agents. This method is based upon the fact that when copper ion is added to a water sample and the pH adjusted to 10, the only copper that remains in solution is that which is in a complexed or chelated form. The precipitate which comes out of the solution at pH 10 contains the copper which is not complexed or chelated and is removed by filtration. The copper remaining in solution is measured by atomic absorption. This copper concentration is a measure of the amount of chelating agent in the water and is called the copper equivalent chelating capacity of the water. The method was used on a number of natural water samples. It was found, for example, that normal creek water contains about one milligram per liter copper equivalent chelating capacity. Water supporting algal growth typically contains about the same level. Raw sewage from a nonindustrial source typically contains around 3 milligrams per liter copper equivalent chelating capacity, whereas properly treated sewage effluent contains 1 milligram per liter or less. The method was extended to the analysis of cyanide ion, a water pollutant found in mining and metal processing effluents. It is applicable to cyanide and provides a simple and convenient method for the analysis of this pollutant. In the final few weeks of the project, a new method was developed in which the copper is solublized from a copper-containing chelating ion exchange resin. This method is much more rapid than the first method described, though somewhat more subject to interferences. It is applicable to automated procedures and as a detection system for chelating agents separated by liquid chromatography. It is extremely sensitive and can detect as little as 5x10^-7 millimoles of NTA. These applications of the method are being pursued under a USDI-OWRR matching grant starting on July 1, 1973.Project # A-056-MO Agreement # 14-31-0001-382

A New and Unusual Pathway for the Reaction of Neocarzinostatin Chromophore with Thiols. Revised Structure of the Protein-Directed Thiol Adduct

Neocarzinostatin (holo-NCS) is an antitumor antibiotic comprising a nonprotein chromophore component (1) and a 113- amino acid carrier protein (apo-NCS). Goldberg and coworkers first demonstrated that the reaction of the isolated chromophore (1) with thiols in the presence of double-stranded DNA leads to DNA cleavage by a free-radical mechanism. The pathway shown in Scheme 1 was later proposed to account for this activity, a proposal that is now supported by a considerable body of evidence. In 1992, Saito and co-workers showed that the reaction of holo-NCS with small thiols, such as β-mercaptoethanol (BME), takes a different course, to form a product that is formally a 1:1:1 adduct of thiol, 1, and water. Structure 2 was proposed for this adduct, along with the mechanistic pathway shown in Scheme 2. Complicating the analysis was the fact that 2 was an inseparable mixture of two components, present in equal parts

Timed Implementation Relations for the Distributed Test Architecture

In order to test systems that have physically distributed interfaces, called ports, we might use a distributed approach in which there is a separate tester at each port. If the testers do not synchronise during testing then we cannot always determine the relative order of events observed at different ports and this leads to new notions of correctness that have been described using corresponding implementation relations. We study the situation in which each tester has a local clock and timestamps its observations. If we know nothing about how the local clocks relate then this does not affect the implementation relation while if the local clocks agree exactly then we can reconstruct the sequence of observations made. In practice, however, we are likely to be between these extremes: the local clocks will not agree exactly but we have some information regarding how they can differ. We start by assuming that a local tester interacts synchronously with the corresponding port of the system under test and then extend this to the case where communications can be asynchronous, considering both the first-in-first-out (FIFO) case and the non-FIFO case. The new implementation relations are stronger than implementation relations for distributed testing that do not use timestamps but still reflect the distributed nature of observations. This paper explores these alternatives and derives corresponding implementation relations