Showing papers by "Nicholls State University published in 2002"

Supplier selection problem: a comparison of the total cost of ownership and analytic hierarchy process approaches

Abstract: Supplier selection and evaluation are arguably one of the most critical functions for the success of an organization. Several approaches exist in the literature to objectively evaluate suppliers, including analytic hierarchy process and total cost of ownership. Analytic hierarchy process provides a framework to cope with multiple criteria situations involving supplier selection, while the total cost of ownership is a methodology and philosophy, which look beyond just the price of a purchase to better understand and manage costs in selecting and maintaining relationships with suppliers. This paper illustrates the two approaches and provides a comparison.

Activity of sulfate-reducing bacteria in human periodontal pocket.

Abstract: Samples of subgingival dental tissues were examined for the presence of sulfate-reducing bacteria (SRB). Using enrichment cultures, SRBs were detected in 9 of 17 individuals. A pure culture of SRB was obtained from one sample collected from a patient with type IV periodontal disease. The characterization of this isolate showed that it belongs to the genus Desulfovibrio. The isolate used pyruvate, lactate, glucose, fructose, and ethanol as the sole source of carbon. However, the isolate was unable to use acetate and methanol as a carbon source, indicating it as an incomplete oxidizer unable to carry out the terminal oxidation of substrates. Apart from using sulfate as electron acceptor, the isolate also used thiosulfate and nitrate as an electron acceptor. It has the ability to use a variety of nitrogen sources, including ammonium chloride, nitrate, and glutamate. The optimum growth temperature of the isolate was 37°C and the optimum pH for growth was 6.8. The SRB isolate contained the electron carrier des...

Atomic absorption spectrometric determination of chromium, copper, lead, mercury, and zinc in sediments collected in Bayou d'Inde, southwestern Louisiana.

Abstract: The concentrations of the metals chromium (Cr), copper (Cu), lead (Pb), mercury (Hg), and zinc (Zn) were determined in sediment cores taken from Bayou d'Inde in southwestern Louisiana. Previous studies had reported elevated concentrations of these trace metals in sediments along this waterway. The current study, conducted more than a decade later, was designed to determine if these metals had migrated from the areas of highest concentrations. Concentrations as high as 400 mg/kg for Cr, 1100 mg/kg for Cu, 10 mg/kg for Hg, and 600 mg/kg for Pb and Zn were found. Areas of high concentrations of metals were isolated within a distance of about 1 km from the most highly contaminated areas in the bayou. Low concentrations of metals were found at the mouth of the bayou. Estimated sedimentation rates of 0.67-1.2 cm/yr were based on the burial of the sediments originally studied. The concentrations of the metals studied remained high and were also highly localized, both spatially and temporally.

Methanogenesis from furfural by defined mixed cultures.

Abstract: Methanogenesis from furfural by defined mixed cultures was studied. Under sulfate-reducing conditions, a Desulfovibrio strain was used as the furfural-degrading species producing acetic acid. This sulfate-reducing bacterium (SRB) Desulfovibrio strain B is an incomplete oxidizer, unable to carry out the terminal oxidation of organic substrates, leaving acetic acid as the end product. Introduction of acetate-utilizing methanogenic archaeon Methanosarcina barkeri 227 converted acetic acid to methane. This well-defined mixed consortium used furfural as its sole source of carbon and converted it to methane and CO(2). In the mixed culture, when a methanogen inhibitor was used in the culture medium, furfural was converted to acetic acid by the Desulfovibrio strain B, but acetic acid did not undergo further metabolism. On the other hand, when the growth of Desulfovibrio in the consortium was suppressed with a specific SRB inhibitor, namely molybdate, furfural was not degraded. Thus, the metabolic activities of both Desulfovibrio strain B and M. barkeri 227 were essential for the complete degradation of furfural.

Culinary Education and Computer Technology: A Longitudinal Study

Abstract: Using survey methodology this study compared 1996 and 2001 culinary educator sample perceptions of current and future computer technology use in 14 categories of general and industry computer applications and eight questions about the respondents programs technology requirements. Also four questions asked respondents to rate recipe/ inventory systems used in their programs. There is a discussion that considers changes in educator perceptions of program technology requirements and student current and future application usage. In general, programs were significantly increasing and planning to increase technology curricula in the 2001 sample. In general, both current and future technology use by culinary students is increasing with ease of student and faculty use the most important attributes of recipe/inventory systems. The respondents felt that computer use is considered essential for culinary graduates and that a variety of applications should be integrated into the information system of the culinary prog...

Recent applications of flame atomic absorption spectrometry to environmental measurements

Abstract: Atomic absorption spectroscopy is very useful for the determination of a large number of elements, especially at trace levels. It is a widely used technique for analysis of a wide variety of sample matrices including biota, soils, and water. Atomic absorption spectroscopy is a very reputable technique that is inexpensive and delivers accurate results even in a complex matrix. This review focuses on the applications of flame atomic absorption spectroscopy to environmental measurements, and is mainly based on papers published from 1999–2002.

The Crawfish and the Aztec treasure maze: adventures in data structures

Abstract: Teaching data structures and other CS1/CS2 subjects can be challenging. Previous research has shown that using manipulatives and visualization tools may help students comprehend these abstract concepts. This paper illustrates how students can use a pez dispenser as a stack to gain first hand experience with many CS1/CS2 topics. In addition to giving students candy, we appeal to their sense of adventure by presenting a fictitious account of how the Aztecs might have used pez-like stacks. This tale is meant to supplement homework and class discussion concerning stack definition, algorithm design, recursion, tree traversal, and operation pre- and post-conditions.

Thermal neutron activation analysis—an important analytical tool

Abstract: This review is intended to present an introduction to the use of thermal neutron activation analysis (TNAA) as an analytical technique for the determination of elements in almost all kinds of matrices. This method of analysis is generally multi-element and experimental conditions can be designed to be nondestructive to the sample. This review will focus on thermal neutron activation as this technique allows determination of approximately two-thirds of the elements on the periodic chart. There are also more and wider spread facilities in the United States that offer these services. The available facilities are located across the United States and are generally accessible to everyone. The review will also detail the advantages and disadvantages of TNAA compared to other common spectroscopic methods. An outline of the general procedure for performing the analysis of the elements using activation analysis is presented to emphasize the ease of using this technique. The outline is divided into sections...

Multimedia, It's How You Use It

Abstract: SUMMARY The current study chronicles what one professor learned from teaching a distance education course with and without the aid of PowerPoint multimedia presentation software. It compares student ratings of three lectures from the same classes by the same professor; the first, a traditional lecture without any audiovisual aids; the second, a lecture supplemented by PowerPoint notes outlining the lecture; and finally, a multimedia lecture utilizing PowerPoint notes with pictures, music and animations. Students reacted no differently to any of the presentations when delivered by an experienced teacher. The students did, however, prefer PowerPoint multimedia to PowerPoint outline presentations. Suggestions for the optimal uses of presentation software are provided.

To C/sup ++/ or to Java, that is the question! Featuring a test plan and an automated testing assistant for object oriented testing

Abstract: The decision to teach C/sup ++/ or Java or even both as the introductory language for computer science majors has always been, and continues to be an ongoing predicament. The paper submits analyses based on a survey conducted to provide evidence on which language is better as the primary language taught as an introductory language for computer science majors as well as presenting a test plan with an automated testing assistant that is based on the test plan. The purpose of the automated testing assistant is to help students test their programs in the language chosen by the survey. Testing is a crucial phase of object oriented (OO) software development. It is very necessary to plan and implement the testing of an OO system in a very effective manner. Efficiency includes (1) uncover errors by using an automated testing assistant, (2) prevent errors from recurring by having a history file which keeps track of all discovered errors from previous runs, and (3) reduce unnecessary testing by having a fruitful test plan. Testing an OO software needs to be rigorous yet carried out easily and effectively. The availability of an automated testing assistant will enforce rigorous yet easy to conduct testing.