Update of Distribution of the Chestnut Lamprey in Arkansas

Most lamprey species other than sea lampreys have been poorly studied in North America. The chestnut lamprey, Ichthyomyzon castaneus, has a distribution within the Mississippi River and Hudson Bay drainage systems, and the Great Lakes. Since the text Fishes of Arkansas was published in 1988, few papers have been published to update the statewide distribution of this lamprey. We incorporated our electrofishing sampling results with gray and published literature to describe the distribution of this species in the drainage basins of the State of Arkansas. Reported are records of 250 chestnut lamprey specimens, over a 90 year period, from 47 different waterbodies in the state

Tribute

I remember sitting in the law auditorium late in our first semester of law school. Listening to a handful of professors, we heard about the electives offered for second semester. I am not sure how I felt prior to entering the auditorium that day. I do remember how I felt afterwards -- I was going to get into Professor Clark’s class. From what I’ve heard, her legal history seminar was by far the most highly coveted of the first-year electives. That’s no surprise, though -- you could almost feel her excitement as she spoke about the course. On hearing that I had been admitted to Professor Clark’s class, a friend who had not been so fortunate said, “You’re so lucky.” She was right. Absolutely

Distributed-Pair Programming can work well and is not just Distributed Pair-Programming

Background: Distributed Pair Programming can be performed via screensharing or via a distributed IDE. The latter offers the freedom of concurrent editing (which may be helpful or damaging) and has even more awareness deficits than screen sharing. Objective: Characterize how competent distributed pair programmers may handle this additional freedom and these additional awareness deficits and characterize the impacts on the pair programming process. Method: A revelatory case study, based on direct observation of a single, highly competent distributed pair of industrial software developers during a 3-day collaboration. We use recordings of these sessions and conceptualize the phenomena seen. Results: 1. Skilled pairs may bridge the awareness deficits without visible obstruction of the overall process. 2. Skilled pairs may use the additional editing freedom in a useful limited fashion, resulting in potentially better fluency of the process than local pair programming. Conclusion: When applied skillfully in an appropriate context, distributed-pair programming can (not will!) work at least as well as local pair programming

Size Selective Parasitism of Rainbow Trout (Oncorhynchus mykiss) by Chestnut Lampreys (Ichthyomyzon castaneus) in an Artificial Setting

Paradigms of optimal resource utilization by animals, both classical and more recent, were not originally developed in the context of parasitism. Though this oversight has slowly been reversed, little attention has been paid to optimal resource utilization by parasitic fishes, such as lampreys. Multiple explanations for host size selection by parasitic lampreys may be plausible, but results from previous studies have been inconsistent. We studied host size selection by Chestnut Lampreys (Ichthyomyzon castaneus) parasitizing Rainbow Trout (Oncorhynchus mykiss) in fish hatchery raceways in north central Arkansas during the late winter and early spring of 2013. Parasitized Rainbow Trout were significantly shorter than non-parasitized conspecifics. Using the relative weight metric of condition, evidence was found that parasitized Rainbow Trout were in better condition than non-parasitized Rainbow Trout. Our findings are not consistent with previous studies of parasitic lamprey host size selection, but do suggest that Chestnut Lampreys are capable of determining a fish’s suitability as a host based on their plumpness even in a setting with low host size heterogeneity and high host density

Automating embedded analysis capabilities and managing software complexity in multiphysics simulation part II: application to partial differential equations

A template-based generic programming approach was presented in a previous paper that separates the development effort of programming a physical model from that of computing additional quantities, such as derivatives, needed for embedded analysis algorithms. In this paper, we describe the implementation details for using the template-based generic programming approach for simulation and analysis of partial differential equations (PDEs). We detail several of the hurdles that we have encountered, and some of the software infrastructure developed to overcome them. We end with a demonstration where we present shape optimization and uncertainty quantification results for a 3D PDE application

Scaling behavior in economics: I. Empirical results for company growth

We address the question of the growth of firm size. To this end, we analyze the Compustat data base comprising all publicly-traded United States manufacturing firms within the years 1974-1993. We find that the distribution of firm sizes remains stable for the 20 years we study, i.e., the mean value and standard deviation remain approximately constant. We study the distribution of sizes of the ``new'' companies in each year and find it to be well approximated by a log-normal. We find (i) the distribution of the logarithm of the growth rates, for a fixed growth period of one year, and for companies with approximately the same size $S$ displays an exponential form, and (ii) the fluctuations in the growth rates -- measured by the width of this distribution $\sigma_1$ -- scale as a power law with $S$, $\sigma_1\sim S^{-\beta}$. We find that the exponent $\beta$ takes the same value, within the error bars, for several measures of the size of a company. In particular, we obtain: $\beta=0.20\pm0.03$ for sales, $\beta=0.18\pm0.03$ for number of employees, $\beta=0.18\pm0.03$ for assets, $\beta=0.18\pm0.03$ for cost of goods sold, and $\beta=0.20\pm0.03$ for property, plant, & equipment.Comment: 16 pages LateX, RevTeX 3, 10 figures, to appear J. Phys. I France (April 1997

Scaling behavior in economics: II. Modeling of company growth

In the preceding paper we presented empirical results describing the growth of publicly-traded United States manufacturing firms within the years 1974--1993. Our results suggest that the data can be described by a scaling approach. Here, we propose models that may lead to some insight into these phenomena. First, we study a model in which the growth rate of a company is affected by a tendency to retain an ``optimal'' size. That model leads to an exponential distribution of the logarithm of the growth rate in agreement with the empirical results. Then, we study a hierarchical tree-like model of a company that enables us to relate the two parameters of the model to the exponent $\beta$, which describes the dependence of the standard deviation of the distribution of growth rates on size. We find that $\beta = -\ln \Pi / \ln z$, where $z$ defines the mean branching ratio of the hierarchical tree and $\Pi$ is the probability that the lower levels follow the policy of higher levels in the hierarchy. We also study the distribution of growth rates of this hierarchical model. We find that the distribution is consistent with the exponential form found empirically.Comment: 19 pages LateX, RevTeX 3, 6 figures, to appear J. Phys. I France (April 1997

The Ursinus Weekly, December 12, 1938

Rose marionettes arrive tomorrow • Guest artists praise work of choir in Thursday rendition of the Messiah • Three trips scheduled for men\u27s debate team • Soph hop\u27s Don Pike signed to play return engagement for interfraternity-sorority ball • Baugh to talk Founders\u27 Day • Student party, banquet feature Christmas week • Curtain Club to stage \u27Mr. Pim\u27 at Spring City • Seniors present comedy, ball as final social contributions • The Oklahoma Daily gives Carter tribute • The Skipped diploma • Japan and China films shown on Wednesday as part of local Far East emergency drive • New IRC Quarterly reflects student views on the Netherlands and collective security • Michael addresses seniors • Basketeers priming for opening game of season; squad, except for Bodley, intact from last year • Men\u27s ping pong finals to be played this week • Court team, with seven veterans, greatly improved this year • Brodbeck, Curtis meet in intramural playoffs • Mrs. Hashagen to sponsor new Art Club just organized • Brotherhood to discuss popular Christmas stories • Borrell head of new sorority • Seniors urged to apply now for Varsity Club loanshttps://digitalcommons.ursinus.edu/weekly/1856/thumbnail.jp

Power Law Scaling for a System of Interacting Units with Complex Internal Structure

We study the dynamics of a system composed of interacting units each with a complex internal structure comprising many subunits. We consider the case in which each subunit grows in a multiplicative manner. We propose a model for such systems in which the interaction among the units is treated in a mean field approximation and the interaction among subunits is nonlinear. To test the model, we identify a large data base spanning 20 years, and find that the model correctly predicts a variety of empirical results.Comment: 4 pages with 4 postscript figures (uses Revtex 3.1, Latex2e, multicol.sty, epsf.sty and rotate.sty). Submitted to PR