Technical Paper No. 2: Student Evaluation of Faculty Teaching Performance: Analysis of Four Years' Data

Student evaluation of faculty teaching performance has provided an important source of evidence in making faculty personnel decisions at Sangamon State University. Students have been asked to rate the competency and the teaching ability of their instructors; specifically, near the end of each term, students have rated faculty using the following two items: 1) Do you think this teacher is competent in the content or matter offered in this course? 2) Overall, do you consider this person a good teacher? The two items were administered from 1971 to 1975, and a record of the resultant data has been maintained. The research reported in this paper was motivated by a desire to look at the stability and reliability of the evaluations obtained from the two item evaluations over the four year period.The present paper reports on the amount of agreement between the ratings given on the teaching item and the ratings on the competency item. The effect of rewording the teaching item on the ratings is also reported.published or submitted for publicationis peer reviewe

Two-Mirror Apodization for High-Contrast Imaging

Direct detection of extrasolar planets will require imaging systems capable of unprecedented contrast. Apodized pupils provide an attractive way to achieve such contrast but they are difficult, perhaps impossible, to manufacture to the required tolerance and they absorb about 90% of the light in order to create the apodization, which of course lengthens the exposure times needed for planet detection. A recently proposed alternative is to use two mirrors to accomplish the apodization. With such a system, no light is lost. In this paper, we provide a careful mathematical analysis, using one dimensional mirrors, of the on-axis and off-axis performance of such a two-mirror apodization system. There appear to be advantages and disadvantages to this approach. In addition to not losing any light, we show that the nonuniformity of the apodization implies an extra magnification of off-axis sources and thereby makes it possible to build a real system with about half the aperture that one would otherwise require or, equivalently, resolve planets at about half the angular separation as one can achieve with standard apodization. More specifically, ignoring pointing error and stellar disk size, a planet at $1.7 \lambda/D$ ought to be at the edge of detectability. However, we show that the non-zero size of a stellar disk pushes the threshold for high-contrast so that a planet must be at least $2.5 \lambda/D$ from its star to be detectable. The off-axis analysis of two-dimensional mirrors is left for future study.Comment: 21 pages, 7 figures. For author's webpage version see http://www.orfe.princeton.edu/~rvdb/tex/piaa/ms.pdf This version has improved figures and addresses comments of a refere

Nonlinear dynamics of global atmospheric and Earth-system processes

General Circulation Model (GCM) studies of the atmospheric response to change boundary conditions are discussed. Results are reported on an extensive series of numerical studies based on the National Center for Atmospheric Research (NCAR) Community Climate Model (CCM) general circulation model. In these studies the authors determined the response to systematic changes in atmospheric CO2 ranging from 100 to 1000 ppm; to changes in the prescribed sea surface temperature (SST) in the Gulf of Mexico, such as occurred during the deglaciation phase of the last ice age; to changes in soil moisture over North America; and to changes in sea ice extent in the Southern Hemisphere. Study results show that the response of surface temperature and other variables is nearly logarithmic, with lower levels of CO2 implying greater sensitivity of the atmospheric state to changes in CO2. It was found that the surface temperature of the Gulf of Mexico exerts considerable control over the storm track and behavior of storm systems over the North Atlantic through its influence on evaporation and the source of latent heat. It was found that reductions in soil moisture can play a significant role in amplifying and maintaining North American drought, particularly when a negative soil moisture anomaly prevails late in the spring

Nonlinear dynamics of global atmospheric and Earth-system processes

Researchers are continuing their studies of the nonlinear dynamics of global weather systems. Sensitivity analyses of large-scale dynamical models of the atmosphere (i.e., general circulation models i.e., GCM's) were performed to establish the role of satellite-signatures of soil moisture, sea surface temperature, snow cover, and sea ice as crucial boundary conditions determining global weather variability. To complete their study of the bimodality of the planetary wave states, they are using the dynamical systems approach to construct a low-order theoretical explanation of this phenomenon. This work should have important implications for extended range forecasting of low-frequency oscillations, elucidating the mechanisms for the transitions between the two wave modes. Researchers are using the methods of jump analysis and attractor dimension analysis to examine the long-term satellite records of significant variables (e.g., long wave radiation, and cloud amount), to explore the nature of mode transitions in the atmosphere, and to determine the minimum number of equations needed to describe the main weather variations with a low-order dynamical system. Where feasible they will continue to explore the applicability of the methods of complex dynamical systems analysis to the study of the global earth-system from an integrative viewpoint involving the roles of geochemical cycling and the interactive behavior of the atmosphere, hydrosphere, and biosphere

Effects of Organic Compounds on Amphibian Reproduction

Aquatic toxicity tests were conducted with atrazine, carbon tetrachloride, chloroform, methylene chloride, trisodium nitrilotriacetic acid (NTA), and phenol. Each compound was administered to developmental stages of three to five amphibian species. Exposure was initiated at fertilization and maintained through 4 days posthatching. Test responses included lethality and teratogenesis. Different amphibian species exhibited varying degrees of tolerance to the selected compounds. Greatest tolerance usually was observed for the more broadly adapted semi-aquatic and terrestrial species (e.g., Bufo americanus, Bufo fowleri). The more sensitive amphibians usually included those species which normally are restricted to aquatic or moist habitats (e.g., Rana catesbeiana, Rana pipiens). Median lethal concentrattons (mg/1) determined at 4 days posthatching ranged from 0.41 to \u3e 48 for atrazine, 0.90 to 2.83 for carbon tetrachloride, 0.27 to 35.14 for chloroform, 17.78 to \u3e 32 for methylene chloride, 39.3 to 252.3 for NTA, and 0.04 to \u3e 0.89 for phenol. The most toxic compounds always included phenol, carbon tetrachloride, and atrazine, and the least toxic consistently were NTA and methylene chloride. for three chlorinated alkanes, including methylene chloride (CH2Cl2), chloroform (CHCl3), and carbon tetrachloride (CCl4), toxicity increased with chlorination. Toxicity of the different compounds was further characterized by calculating concentrations which produced embryo-larval lethality or teratogenesis at frequencies of 10% (LC10) and 1% (LC1). On the basis of LC1 values, Hyla crucifer, Rana catesbeiana, and Rana pipiens generally exhibited sensitivity equal to or slightly greater than that observed for embryolarval stages of the rainbow trout

The Influence of Citrate, Maltolate and Fluoride on the Gastrointestinal Absorption of Aluminum at a Drinking Water-Relevant Concentration: A \u3csup\u3e26\u3c/sup\u3eAl and \u3csup\u3e14\u3c/sup\u3eC Study

The objectives were to test the null hypotheses that (1) citrate, maltolate, and fluoride do not significantly influence oral Al bioavailability, Cmax or Tmax at an Al dose relevant to drinking water exposure; and (2) Al citrate and maltolate are absorbed intact from the gastrointestinal tract. Male Fisher rats were given 1 ml of solution intra-gastrically containing 1 nCi 26Al (65 nmol total Al) as the Al3+ ion, or as complexes with 14C-citrate, 14C-maltolate or fluoride, during concurrent 27Al iv infusion. Blood was repeatedly collected for serum 26Al, total Al and 14C quantification. Absorption parameters were estimated using WinNonlin. Al bioavailability, Cmax and Tmax from the ion, citrate, maltolate, and fluoride were 0.29 ± 0.11%, 0.61 ± 0.31%, 0.50 ± 0.25%, and 0.35 ± 0.10%; 659 ± 195, 1073 ± 250, 881 ± 356, and 880 ± 295 fg/ml; and 1.2 ± 0.9, 1.0 ± 1.1, 1.3 ± 1.0, and 1.0 ± 0.9 h (X ± SD) respectively. Serum 14C was ∼100 times higher than 26Al. The results suggest a non-significant enhancement of oral Al bioavailability by citrate and maltolate, some Al complex dissociation in the GI tract, and less absorption of Al than citrate or maltolate. The presence of citrate, maltolate and fluoride, at a similar molar concentration to Al, would not be expected to greatly influence Al absorption from drinking water

Application of dynamical systems theory to global weather phenomena revealed by satellite imagery

Theoretical studies of low frequency and seasonal weather variability; dynamical properties of observational and general circulation model (GCM)-generated records; effects of the hydrologic cycle and latent heat release on extratropical weather; and Earth-system science studies are summarized

Chelating Compounds and Immobilized Tethered Chelators

Novel compounds useful as chelators, intermediates for their production and methods for removing trivalent and tetravalent metal ions from solution are presented.https://irl.umsl.edu/patents/1063/thumbnail.jp