Showing papers by "Mississippi State University published in 2000"
TL;DR: Four factors that are critical to Web site success in EC were identified: information and service quality, system use, playfulness, and system design quality.
1,566 citations
TL;DR: Worked examples are instructional devices that provide an expert's problem solution for a learner to study as discussed by the authors, which is a cognitiveexperimental program that has relevance to classroom instruction and the broader educational research community.
Abstract: Worked examples are instructional devices that provide an expert's problem solution for a learner to study. Worked-examples research is a cognitive-experimental program that has relevance to classroom instruction and the broader educational research community. A frame- work for organizing the findings of this research is proposed, leading to instructional design principles. For instance, one instructional design principle suggests that effective examples have highly integrated components. They employ multiple modalities in presentation and emphasize conceptual structure by labeling or segmenting. At the lesson level, effective instruction employs multiple examples for each conceptual problem type, varies example formats within problem type, and employs surface features to signal deep structure. Also, examples should be presented in close proximity to matched practice problems. More- over, learners can be encouraged through direct training or by the structure of the worked example to actively self:explain ...
955 citations
TL;DR: In this article, micellar solutions were found to increase gas hydrate formation rate and alter formation mechanism for ethane and natural gas hydrates, which overcomes major limitations of future hydrate use in an industrial scale natural gas storage process.
591 citations
TL;DR: In this article, the authors trace the development of the concept of soil quality and explore the use of soil chemical and physical properties as determinants of forest soil quality, and present challenges and opportunities for forest soil scientists to play a relevant role in assessment and advancement of sustainable forest management by developing soil quality as an indicator of sustainability.
580 citations
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TL;DR: This work presents an algorithm to approximate any surface arbitrarily closely with a normal semi-regular mesh, which is useful in numerous applications such as compression, filtering, rendering, texturing, and modeling.
Abstract: Normal meshes are new fundamental surface descriptions inspired by differential geometry. A normal mesh is a multiresolution mesh where each level can be written as a normal offset from a coarser version. Hence the mesh can be stored with a single float per vertex. We present an algorithm to approximate any surface arbitrarily closely with a normal semi-regular mesh. Normal meshes can be useful in numerous applications such as compression, filtering, rendering, texturing, and modeling.
406 citations
TL;DR: This article examined the meaning of the veil among Muslim religious elites and Islamic feminists and examined how these discursive disputes affect gender identity negotiation among veiled and unveiled Muslim women living in Austin, Texas.
Abstract: The increasingly pervasive practice of veiling among Muslim women has stimulated a great deal of scholarly investigation and debate. This study brings empirical evidence to bear on current debates about the meaning of the veil in Islam. This article first examines the conflicting meanings of the veil among Muslim religious elites and Islamic feminists. Although the dominant gender discourse among Muslim elites strongly favors this cultural practice, an antiveiling discourse promulgated by Islamic feminists has gained ground within recent years. This study then examines how these discursive disputes affect gender identity negotiation among veiled and unveiled Muslim women living in Austin, Texas. Interviews with these women highlight how their gender identities reproduce and reformulate existing Muslim gender discourses. Special attention is paid to the subjective disparities and points of congruence between both groups of respondents. This study concludes by suggesting avenues for future research on the i...
328 citations
TL;DR: This model is the first to show in a single experiment all the major adaptive stress responses of chickens, as well as relative weights of the major immunobiological organs, which were decreased and increased due to lipid and moisture accumulation.
312 citations
TL;DR: Dual-electrode detection in the series configuration was shown to be useful for the selective monitoring of species undergoing chemically reversible redox reactions and for peak identification in the electropherogram of an unresolved mixture.
Abstract: The development of a poly(dimethylsiloxane)-based (PDMS-based) microchip electrophoresis system employing dual-electrode electrochemical detection is described. This is the first report of dual-electrode electrochemical detection in a microchip format and of electrochemical detection on chips fabricated from PDMS. The device described in this paper consists of a top layer of PDMS containing the separation and injection channels and a bottom glass layer onto which gold detection electrodes have been deposited. The two layers form a tight reversible seal, eliminating the need for high-temperature bonding, which can be detrimental to electrode stability. The channels can also be temporarily removed for cleaning, significantly extending the lifetime of the chip. The performance of the chip was evaluated using catechol as a test compound. The response was linear from 10 to 500 μM with an LOD (S/N = 3) of 4 μM and a sensitivity of 45.9 pA/μM. Collection efficiencies for catechol ranged from 28.7 to 25.9% at fie...
297 citations
TL;DR: In this article, the potential of peanut hull pellets to capture metal ions from wastewater and compared their performance to that of raw peanut hulls and a commercial grade ion exchange resins was assessed.
279 citations
TL;DR: Poly(dimethylsiloxane) capillary electrophoresis (CE) microchips were modified by a dynamic coating method that provided stable electroosmotic flow (EOF) with respect to pH and no significant variation for separation and electrochemical detection of dopamine and hydroquinone between coated and uncoated channels was observed.
Abstract: Poly(dimethylsiloxane) (PDMS) capillary electrophoresis (CE) microchips were modified by a dynamic coating method that provided stable electroosmotic flow (EOF) with respect to pH. The separation channel was coated with a polymer bilayer consisting of a cationic layer of Polybrene (PB) and an anionic layer of dextran sulfate (DS). According to the difference in charge, PB- and PB/DS-coated channels supported EOF in different directions; however, both methods of channel coating exhibited a pH-independent EOF in the pH range of 5−10 due to chemical control of the effective ζ-potential. The endurance of the PB-coated layer was determined to be 50 runs at pH 3.0, while PB/DS-coated chips had a stable EOF for more than 100 runs. The effect of substrate composition and chip-sealing methodology was also evaluated. All tested chips showed the same EOF on the PB/DS-coated channels, as compared to uncoated chips, which varied significantly. No significant variation for separation and electrochemical detection of do...
274 citations
TL;DR: In this paper, a conceptual model is presented that links nonverbal communication (kinesics, paralanguage, proxemics, and physical appearance), customer affect, and consumers' evaluations of service providers (with respect to credibility, friendliness, competence, empathy, courtesy, and trustworthiness).
Abstract: Although the verbal components of service encounters have been investigated, the nonverbal aspects of employee‐customer interactions have remained virtually unexplored in the marketing literature. Thus, the purpose of this paper is to explore the importance of service employees’ nonverbal communication during service interactions. Specifically, a conceptual model is presented that links nonverbal communication (kinesics, paralanguage, proxemics, and physical appearance), customer affect, and consumers’ evaluations of service providers (with respect to credibility, friendliness, competence, empathy, courtesy, and trustworthiness). Further, the importance of nonverbal elements is discussed and managerial implications are given.
TL;DR: The higher number of larvae on refuge plants in field tests indicate that a “separate refuge” will be more effective at conserving susceptible larvae than a ‘mixed refuge’ and would thereby reduce the number of homozygous resistant (RR) offspring.
Abstract: Several important crops have been engineered to express toxins of Bacillus thuringiensis (Bt) for insect control. In 1999, US farmers planted nearly 8 million hectares (nearly 20 million acres) of transgenic Bt crops approved by the EPA. Bt-transgenic plants can greatly reduce the use of broader spectrum insecticides, but insect resistance may hinder this technology. Present resistance management strategies rely on a “refuge” composed of non-Bt plants to conserve susceptible alleles. We have used Bt-transgenic broccoli plants and the diamondback moth as a model system to examine resistance management strategies. The higher number of larvae on refuge plants in our field tests indicate that a “separate refuge” will be more effective at conserving susceptible larvae than a “mixed refuge” and would thereby reduce the number of homozygous resistant (RR) offspring. Our field tests also examined the strategy of spraying the refuge to prevent economic loss to the crop while maintaining susceptible alleles in the population. Results indicate that great care must be taken to ensure that refuges, particularly those sprayed with efficacious insecticides, produce adequate numbers of susceptible alleles. Each insect/Bt crop system may have unique management requirements because of the biology of the insect, but our studies validate the need for a refuge. As we learn more about how to refine our present resistance management strategies, it is important to also develop the next generation of technology and implementation strategies.
TL;DR: It is concluded that the combination of a commercial antioxidant and biocide is synergistic, which implies that extractives may protect wood by more than simply being fungicidal.
TL;DR: It is demonstrated that a unique 33-kD cysteine proteinase accumulates in the whorl in response to larval feeding in maize genotypes derived from Antiquan germ plasm that are resistant to Lepidoptera.
Abstract: Plants respond to insect feeding with a number of defense mechanisms. Using maize genotypes derived from Antiquan germ plasm that are resistant to Lepidoptera, we have demonstrated that a unique 33-kD cysteine proteinase accumulates in the whorl in response to larval feeding. The abundance of the proteinase increased dramatically at the site of larval feeding after 1 hr of infestation and continued to accumulate for as long as 7 days. The 33-kD cysteine proteinase was most abundant in the yellow-green portion of the whorl—the normal site of larval feeding and the tissue that has the greatest inhibitory effect on larval growth in bioassays. The proteinase was expressed in response to wounding and was found in senescent leaves. It may be a marker of programmed cell death. The gene coding for the proteinase, mir1, has been transformed into Black Mexican Sweet callus. When larvae were reared on callus expressing the proteinase, their growth was inhibited ∼60 to 80%. The expression of a cysteine proteinase, instead of a cysteine proteinase inhibitor, may be a novel insect defense mechanism in plants.
TL;DR: In this paper, an exploratory study of customer perceptions of market orientation suggests that a reduced and amended version of a well-known market orientation measurement instrument can meaningfully be applied to customers, and that a strong relationship exists between customer defined market orientation and both service quality and customer satisfaction.
TL;DR: It is concluded that GLP-2 increases intestinal growth in premature, TPN-fed pigs by decreasing proteolysis and apoptosis, whereas enteral nutrition acts via increased protein synthesis and cell proliferation and decreased apoptosis.
Abstract: We wished to determine whether exogenous glucagon-like peptide (GLP)-2 infusion stimulates intestinal growth in parenterally fed immature pigs. Piglets (106–108 days gestation) were given parentera...
TL;DR: In this article, the authors show that acquirers of high-tech targets experience significantly positive abnormal returns, regardless of whether the merger is financed with cash or stock, factors influencing bidder returns are the time period in which the merger occurs, the ownership structure of the acquirer, the high-technology affiliation of acquirers, and the ownership status of the target.
Abstract: The distinctive high-growth, high-risk nature of technology-based industries raises important questions about the creation of wealth in high-tech takeovers. Do investors perceive acquisitions of high-tech targets to have strong potential for value creation? Or, given the large degree of uncertainty associated with many high-tech companies, is the market skeptical of the potential benefits of high-tech acquisitions? Our results show that acquirers of high-tech targets experience significantly positive abnormal returns, regardless of whether the merger is financed with cash or stock. Factors influencing bidder returns are the time period in which the merger occurs, the ownership structure of the acquirer, the high-tech affiliation of acquirers, and the ownership status of the target.
TL;DR: Results indicate that SBM causes decreased carrier-mediated transport and increased permeability of distal intestinal epithelium for the nutrients, and the capacity of this region to absorb nutrient was diminished.
Abstract: Groups of fresh- and seawater-adapted Atlantic salmon ( Salmo salar L.) and rainbow trout ( Oncorhynchus mykiss ) were fed diets with (SBM diet) or without (control diet) extracted soybean meal (30% of protein substituted with SBM) for 3 weeks. Average fish size per group ranged from 597 to 1763 g. One tank or net pen per species, dietary group and water salinity was used. In vitro nutrient transport ( d -glucose, the l -amino acids aspartate, lysine, methionine, phenylalanine and proline, and the dipeptide glycyl-sarcosine) was measured using intact tissue (everted sleeve method) from the different postgastric intestinal regions. The dimensions of the different intestinal regions were also measured for each treatment group. Results indicate that SBM causes decreased carrier-mediated transport and increased permeability of distal intestinal epithelium for the nutrients, and the capacity of this region to absorb nutrient was diminished. Salinity may also affect the relative contribution of carrier-mediated and independent uptake to total nutrient absorption.
TL;DR: The results show a strong macroecological association between two disparate animal groups with one strongly affecting the assemblage structure of mussel assemblages, indicating that fish community structure is an important determinant of mussels community structure.
Abstract: fish assemblages each significantly accounted for the regional variation in mussel assemblages. Furthermore, mussel assemblages showed strong spatial autocorrelation. Variation partitioning revealed that pure fish effects accounted for 15.4% of the variation in mussel assemblages; pure spatial and environmental effects accounted for 16.1% and 7.8%, respectively. Shared variation among fish, space and environmental variables totaled 40%. Of this shared variation, 36.8% was associated with the fish matrix. Thus, the variation in mussel assemblages that was associated with the distribution and abundance of fishes was substantial (> 50%), indicating that fish community structure is an important determinant of mussel community structure. Although animals commonly disperse plants and, thus, influence the structure of plant communities, our results show a strong macroecological association between two disparate animal groups with one strongly affecting the assemblage structure of
TL;DR: The recovery of the primitive recurrent parent could be improved by marker-assisted backcrossing with SSR markers reported in this experiment, and careful genotyping before introgression into breeding programs is suggested to ensure maximum genetic diversity and integrity of the exotic race-stock donor germplasm.
Abstract: Effective use of converted day-neutral Gossypium hirsutum L. race stocks in cotton genetic improvement programs depends on the extent of genetic variation for desirable alleles and the accurate characterization of the variability within and among germplasm accessions in the collection. This study was conducted to survey the molecular variation in the converted race stock collection by using simple sequence repeat (SSR) DNA markers and to determine the genetic distance of each race stock from a typical G. hirsutum cultigen. The molecular marker data will also provide a measure of the degree to which the recurrent photoperiodic parent has been recovered during backcross conversion to day-neutral stocks. Fifty-six flourescently labeled SSR primer pairs arranged in multiplex bins were used to genotype 97 day-neutral BC 4 F 4 race stock accessions. The majority of the accessions had genetic distances 0.25. In some families, the primitive photoperiodic parent was recovered, and in others there was extensive linkage drag from the day-neutral donor parent. The recovery of the primitive recurrent parent could be improved by marker-assisted backcrossing with SSR markers reported in this experiment. Careful genotyping with SSR markers prior to introgression into breeding programs is suggested to ensure maximum genetic diversity and integrity of the exotic race-stock donor germplasm.
TL;DR: A modification of a previously reported algorithm for mining fuzzy association rules, the concept of fuzzy frequency episodes is defined, and an original algorithm formining fuzzy frequencyepisode is presented.
Abstract: Lee, Stolfo, and Mok 1 previously reported the use of association rules and frequency episodes for mining audit data to gain knowledge for intrusion detection. The integration of association rules and frequency episodes with fuzzy logic can produce more abstract and flexible patterns for intrusion detection, since many quantitative features are involved in intrusion detection and security itself is fuzzy. We present a modification of a previously reported algorithm for mining fuzzy association rules, define the concept of fuzzy frequency episodes, and present an original algorithm for mining fuzzy frequency episodes. We add a normalization step to the procedure for mining fuzzy association rules in order to prevent one data instance from contributing more than others. We also modify the procedure for mining frequency episodes to learn fuzzy frequency episodes. Experimental results show the utility of fuzzy association rules and fuzzy frequency episodes for intrusion detection.
TL;DR: In this article, a direct method for solving variational problems using Legendre wavelets is presented and an operational matrix of integration is first introduced and is utilized to reduce a variational problem to the solution of algebraic equations.
TL;DR: It was found that focus groups using a G SS produced a greater number of better quality ideas, reached consensus more easily, but were less satisfied than groups not supported by a GSS, suggesting that GSS are useful to both practitioners and researchers seeking to maximize the knowledge created in focus group sessions.
TL;DR: In this article, a combined control chart-preventive maintenance strategy is defined for a process which shifts to an out-of-control condition due to a manufacturing equipment failure.
Abstract: The economic design of control charts and the optimization of preventive maintenance policies are two research areas that have recently received a great deal of attention in the quality and reliability literature. Both of these research areas are focused on reducing the costs associated with operating manufacturing processes. In addition, it is widely recognized that the maintenance of manufacturing equipment and the quality of manufactured product are related. However, these two research areas are rarely integrated. In this paper, a combined control chart–preventive maintenance strategy is defined for a process which shifts to an out-of-control condition due to a manufacturing equipment failure. An X¯ chart is used in conjunction with an age-replacement preventive maintenance policy to achieve a reduction in operating costs that is superior to the reduction achieved by using only the control chart or the preventive maintenance policy. This superior cost performance is demonstrated using a simulation-optimization approach.
Proceedings Article•
14 Apr 2000TL;DR: The Boutilier and Poole framework is extended, an implementation of it is described, an investigation of its performance is conducted, and how much this approach improves the computational efficiency of dynamic programming for POMDPs is assessed.
Abstract: Contingent planning - constructing a plan in which action selection is contingent, on imperfect information received during plan execution - can be formalized as the problem of solving a partially observable Markov decision process (POMDP). Traditional dynamic programming algorithms for POMDPs use a flat state representation that enumerates all possible stales and state transitions. By contrast, AI planning algorithms use a factored state representation that supports state abstraction and allows problems with large state spaces to be represented and solved more efficiently. Boutilier and Poole (1996) have recently described how a factored state representation can be exploited by a dynamic programming algorithm for POMDPs. We extend their framework, describe an implementation of it, test its performance, and assess how much this approach improves the computational efficiency of dynamic programming for POMDPs.
TL;DR: Neither dietary levels of iron nor vitamin C or their interaction influenced survival of juvenile channel catfish against E. ictaluri 14-day post challenge, however, the onset of mortality was earlier for fish fed the iron-deficient diet.
TL;DR: In this article, the authors introduced a more meaningful, spatially based measure of concentrated poverty and argued that the effect of concentrated urban poverty on homicide rates should be the same for both racial groups.
Abstract: Research on the link between levels of poverty and homicide in urban areas has persistently reported the existence of a relationship for whites but not for blacks. This is despite the fact that most analysts expect that the higher levels of urban black homicide are due in part to the higher levels of urban black poverty. The present research introduces a more meaningful, spatially based measure of concentrated poverty and argues that the effect of concentrated poverty on homicide rates should be the same for both racial groups. The hypotheses are tested with race-disaggregated data for a sample of central cities circa 1990. The results suggest that, when poverty is measured as a linear spatially based phenomenon, in is a more important determinat of race-specific homicide rates than overall city levels of disadvantage and that the concentration of poverty increases both black and white homicide rather equally.
TL;DR: In this paper, the 2-acetyl-1-pyrroline (2-AP) content of ground brown or milled rice in methylene chloride held at 85°C for 2.5 hr.
Abstract: The aroma of rice plays a role in its consumer acceptability. The popcorn-like smell of aromatic rice stemming primarily from its 2- acetyl-1-pyrroline (2-AP) content is considered desirable by many consumers. Conversely, hexanal has been correlated with off odors in rice that develop from lipid oxidation. A rapid method for 2-AP and hexanal quantification suitable for use in breeding programs, large-scale research efforts, and quality assurance programs is needed. While developing such a method, sample preparation (degree of milling, particle size), solvent extraction time and temperature, and gas chromatographic parameters were studied. Particle size had no influence on 2-AP or hexanal recovered. One extraction solubilized ≈80% of the 2-AP and 56% of the hexanal present in milled rice. The optimum extraction method was assessed to require 0.3 g of ground brown or milled rice in methylene chloride held at 85°C for 2.5 hr. The complete gas chromatographic run requires ≈25 min, and 50 samples can ...
TL;DR: ACTH infusion at 8 IU/kg BW/d for 7 d was determined to be the minimum effective dose that caused physiological stress in broilers.
TL;DR: It is found that conservative Protestant fathers are considerably more likely than their nonevangelical counterparts to engage in paternal supervision and affective parenting.
Abstract: Despite the burgeoning research literature on paternal involvement, the relationship between religion and fatherhood has received remarkably little attention from empirical researchers. Our investi...