Showing papers by "Louisiana State University published in 1996"
TL;DR: A relatively large number of knots and a difference penalty on coefficients of adjacent B-splines are proposed to use and connections to the familiar spline penalty on the integral of the squared second derivative are shown.
Abstract: B-splines are attractive for nonparametric modelling, but choosing the optimal number and positions of knots is a complex task. Equidistant knots can be used, but their small and discrete number allows only limited control over smoothness and fit. We propose to use a relatively large number of knots and a difference penalty on coefficients of adjacent B-splines. We show connections to the familiar spline penalty on the integral of the squared second derivative. A short overview of B-splines, of their construction and of penalized likelihood is presented. We discuss properties of penalized B-splines and propose various criteria for the choice of an optimal penalty parameter. Nonparametric logistic regression, density estimation and scatterplot smoothing are used as examples. Some details of the computations are presented.
3,512 citations
TL;DR: This paper developed and validated short, self-report scales of work-family conflict (WFC) and family-work conflict (FWC) using conceptualizations consistent with the current literature.
Abstract: Researchers report on a 3-sample study that developed and validated short, self-report scales of work-family conflict (WFC) and family-work conflict (FWC). Using conceptualizations consistent with the current literature, the researchers offer content domains and definitions of the constructs. Advocated procedures were used to develop the scales and test dimensionality and internal consistency. Estimates of construct validity are presented by relating the scales to 16 other on- and off-job constructs. Mean-level difference tests between WFC and FWC also provide evidence of validity.
3,093 citations
TL;DR: Analysis of 45 published strategy studies reveals that the implementation of cluster analysis has been often less than ideal, perhaps detracting from the ability of studies to generate knowledge.
Abstract: Cluster analysis is a statistical technique that sorts observations into similar sets or groups. The use of cluster analysis presents a complex challenge because it requires several methodological choices that determine the quality of a cluster solution. This paper chronicles the application of cluster analysis in strategic management research, where the technique has been used since the late 1970s to investigate issues of central importance. Analysis of 45 published strategy studies reveals that the implementation of cluster analysis has been often less than ideal, perhaps detracting from the ability of studies to generate knowledge. Given these findings, suggestions are offered for improving the application of cluster analysis in future inquiry.
2,108 citations
TL;DR: In this article, a multidimensional measure for Leader-Member Exchange (LMX) was developed and validated through item analysis and criterion-related validation using 249 employees representing two organizations.
Abstract: Whether Leader-Member Exchange (LMX) is a unidimensional or a multidimensional construct was assessed through the development and validation of a multidimensional measure. Item analysis involving 302 working students, followed by construct and criterion-related validation using 249 employees representing two organizations resulted in a multidimensional LMX scale. The results provided support for the affect, loyalty, and contribution dimensions identified by Dienesch and Liden (1986), as well as a fourth dimension, professional respect.
1,834 citations
TL;DR: In this article, the relative contribution of indicators of employee-organization exchange and subordinate-supervisor exchange was examined by comparing nested models and finding that perceived organizational support is associated with organizational commitment, whereas leader-member exchange is associated to citizenship and in-role behavior.
Abstract: Social exchange (P. Blau, 1964) and the norm of reciprocity (A. W. Gouldner, 1960) have been used to explain the relationship of perceived organizational support and leader-member exchange with employee attitudes and behavior. Recent empirical research suggests that individuals engage in different reciprocation efforts depending on the exchange partner (e.g., B. L. McNeely & B. M. Meglino, 1994). The purpose of the present study was to further investigate these relationships by examining the relative contribution of indicators of employee-organization exchange and subordinate-supervisor exchange. Structural equation modeling was used to compare nested models. Results indicate that perceived organizational support is associated with organizational commitment, whereas leader-member exchange is associated with citizenship and in-role behavior.
1,630 citations
TL;DR: In this article, the authors test a central proposition of institutional theory, that organizational isomorphism increases organizational legitimacy, and they show that isomorphisms in the strategies of commercial businesses increase organizational legitimacy.
Abstract: This study tests a central proposition of institutional theory, that organizational isomorphism increases organizational legitimacy. Results show that isomorphism in the strategies of commercial ba...
1,460 citations
TL;DR: The indigenous gastrointestinal (GI) tract microflora has profound effects on the anatomical, physiological and immunological development of the host and inhibits colonization of the GI tract by overt exogenous pathogens.
1,154 citations
TL;DR: The Mississippi River system ranks among the world's top 10 rivers in freshwater and sediment inputs to the coastal ocean and contributes 90% of the freshwater loading to the Gulf of Mexico, and terminates amidst one of the United States' most productive fisheries regions and the location of the largest zone of hypoxia, in the western Atlantic Ocean as mentioned in this paper.
Abstract: The Mississippi River system ranks among the world's top 10 rivers in freshwater and sediment inputs to the coastal ocean. The river contributes 90% of the freshwater loading to the Gulf of Mexico, and terminates amidst one of the United States' most productive fisheries regions and the location of the largest zone of hypoxia, in the western Atlantic Ocean. Significant increases in riverine nutrient concentrations and loadings of nitrate and phosphorus and decreases in silicate have occurred this century, and have accelerated since 1950. Consequently, major alterations have occurred in the probable nutrient limitation and overall stoichiometric nutrient balance in the adjacent continental shelf system. Changes in the nutrient balances and reduction in riverine silica loading to, the continental shelf appear to have led to phytoplankton species shifts offshore and to an increase in primary production. The phytoplankton community response, as indicated by long-term changes in biological uptake of silicate and accumulation of biologically bound silica in sediments, has shown how the system has responded to changes in riverine nutrient loadings. Indeed, the accumulation of biologically bound silica in sediments beneath the Mississippi River plume increased during the past two decades, presumably in response to, increased nitrogen loading. The duration, size, and severity of hypoxia has probably increased as a consequence of the increased primary production. Management alternatives directed at water pollution issues within the Mississippi River watershed may have unintended and contrasting impacts on the coastal waters of the northern Gulf of Mexico.
856 citations
TL;DR: This work has identified a large family of proteins having 12-22 % similarity with ACPS, which are putative P-pant transferases, and found three of these proteins, E. coli EntD and o195, and subtilis Sfp, have been overproduced, purified and found to have P- pant transferase activity.
816 citations
TL;DR: In this paper, the connections between information, physics, and computation are examined and the computing power of quantum computers is examined, and it is argued that recently studied quantum computers, which are based on local interactions, cannot simulate quantum physics.
Abstract: This paper presents several observations on the connections between information, physics, and computation. In particular, the computing power of quantum computers is examined. Quantum theory is characterized by superimposed states and nonlocal interactions. It is argued that recently studied quantum computers, which are based on local interactions, cannot simulate quantum physics.
708 citations
TL;DR: The evidence presented suggests that D. radiodurans' ionizing radiation resistance is incidental, a consequence of this organism's adaptation to a common physiological stress, dehydration.
Abstract: Forty-one ionizing radiation-sensitive strains of Deinococcus radiodurans were evaluated for their ability to survive 6 weeks of desiccation. All exhibited a substantial loss of viability upon rehydration compared with wild-type D. radiodurans. Examination of chromosomal DNA from desiccated cultures revealed a time-dependent increase in DNA damage, as measured by an increase in DNA double-strand breaks. The evidence presented suggests that D. radiodurans9 ionizing radiation resistance is incidental, a consequence of this organism9s adaptation to a common physiological stress, dehydration.
TL;DR: In this article, the authors investigate employee performance cues within a hotel service environment, and find that front desk, housekeeping, and parking employee performance have significant effects on perceived quality, whereas front desk and room service employee performance has significant effect on perceived value.
Book•
01 Jan 1996TL;DR: In this article, the S-Transform has been used for the construction of test and generalized functions in a Hilbert space and an operator's Hilbert space, as well as a construction from a Hilbert Space and an Operator.
Abstract: Introduction to White Noise What is White Noise? A Simple Example Background Abstract Wiener Spaces Countably-Hilbert Spaces Nuclear Spaces Gel'fand Triples White Noise as an Infinite Dimensional Calculus White Noise Space A Reconstruction of the Schwartz Space The Space of Test and Generalized Functions Some Examples of Test and Generalized Functions Constructions of Test and Generalized Functions General Ideas for Several Constructions Construction from a Hilbert Space and an Operator General Construction of Kubo and Takenaka Construction of Kondratiev and Streit The S-Transform Wick Tensors and Multiple Weiner Integrals Definition of the S-Transform Examples of Generalized Functions Continuous Versions and Analytic Extensions Continuous Versions of Test Functions Growth Condition and Norm Estimates Analytic Extensions of Test Functions Delta Functions Donsker's Delta Function Kubo-Yokoi Delta Function Continuity of the Delta Functions Characterization Theorems Characterization of Generalized Functions Convergence of Generalized Functions Characterization of Test Functions Wick Product and Convolution Integrable Functions Differential Operators Differential Operators Adjoint Operators Multiplication Operators Gross Differentiation and Gradient Integral Kernel Operators Heuristic Discussion Integral Kernel Operators Gross Laplacian and Number Operator Lambda Operator Translation Operators Representation Theorem Fourier Transforms Definition of the Fourier Transform Representations of the Fourier Transform Basic Properties Decomposition of the Fourier Transform Fourier-Gauss Transforms Characterization of the Fourier Transform Fourier-Mehler Transforms Initial Value Problems Laplacian Operators Semigroup for the Gross Laplacian Semigroup for the Number Operator Levy Laplacian Levy Laplacian by the S-Transform Spherical Mean and the Levy Laplacian Relationship Between Gross and Levy Laplacians Volterra Laplacian Relationship with the Fourier Transform Two-Dimensional Rotations White Noise Integration Informal Motivation Pettis and Bochner Integrals White Noise Integrals An Extension of the Ito Integral Generalization of Ito's Formula One-Sided White Noise Differentiation Stochastic Integral Equations White Noise Integral Equations Feynman Integrals Informal Derivation White Noise Formulation Explicit Calculation Positive Generalized Functions Positive Generalized Functions Construction of Lee Characterization of Hida Measures Appendix A: Notes and Comments Appendix B: Miscellaneous Formulas Bibliography List of Symbols Index
TL;DR: In this paper, the tribological mechanism of diamond-like carbon (DLC) films was investigated and it was shown that the DLC films possess excellent wear resistance and exhibit low values of friction coefficient.
Abstract: In the present work, the tribological mechanism of diamond-like carbon (DLC) films was investigated. DLC films were coated on metallic substrates (M50 steel, Ti-6Al-4V alloy and AISI 440C steel) by methane ion-beam deposition. Pin-on-disc experiments showed that the DLC films possess excellent wear resistance and exhibit low values of friction coefficient (ƒ
TL;DR: Peptide antibacterial activity was tested against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and the peptides were much less lytic toward human erythrocytes than 3T3 cells.
Abstract: De novo antimicrobial peptides with the sequences: (KLAKKLA)n, (KLAKLAK)n (where n = 1, 2, 3), (KALKALK)3, (KLGKKLG)n, and (KAAKKAA)n (where n = 2, 3), were prepared as the C-terminus amides. These peptides were designed to be perfectly amphipathic in helical conformations. Peptide antibacterial activity was tested against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Peptide cytotoxicity was tested against human erythrocytes and 3T3 mouse fibroblasts. The 3T3 cell testing was a much more sensitive test of cytotoxicity. The peptides were much less lytic toward human erythrocytes than 3T3 cells. Peptide secondary structure in aqueous solution, sodium dodecylsulfate micelles, and phospholipid vesicles was estimated using circular dichroism spectroscopy. The leucine/alanine-containing 21-mers were bacteriostatic at 3−8 μM and cytotoxic to 3T3 cells at about 10 μM concentrations. The leucine/alanine- or leucine/glycine-containing 14-mers and the leucine/glycine 21-mer were bacteriostat...
Book•
01 Mar 1996TL;DR: The need for nonlinear process control systems introduction to nonlinear systems topics in nonlinear system theory identification techniques for non linear systems feedback linearization techniques nonlinear model control strategies design of nonlinear state observers artificial neural networks.
Abstract: The need for nonlinear process control systems introduction to nonlinear systems topics in nonlinear system theory identification techniques for nonlinear systems feedback linearization techniques nonlinear model control strategies design of nonlinear state observers artificial neural networks.
TL;DR: Although all the methods are inaccurate, some of them seem to be more accurate than the others and can easily be used in evaluating more fuzzy multiattribute decision making methods.
University of Texas Health Science Center at Houston1, NewYork–Presbyterian Hospital2, University of South Alabama3, University of Texas Southwestern Medical Center4, Washington University in St. Louis5, Harborview Medical Center6, University of Cincinnati7, Louisiana State University8, University of Alabama at Birmingham9, University of Texas Medical Branch10
TL;DR: Wound assessment over time showed that thin split-thickness autografts plus allograft dermal matrix were equivalent to thicker split- Thirteen-day take rates of the dermal Matrix were statistically equivalent to the control autografteds.
Abstract: A multicenter clinical study assessed the ability of an acellular allograft dermal matrix to function as a permanent dermal transplant in full-thickness and deep partial-thickness burns. The study consisted of a pilot phase (24 patients) to identify the optimum protocol and a study phase (43 patients) to evaluate graft performance. Each patient had both a test and a mirror-image or contiguous control site. At the test site, the dermal matrix was grafted to the excised wound base and a split-thickness autograft was simultaneously applied over it. The control site was grafted with a split-thickness autograft alone. Fourteen-day take rates of the dermal matrix were statistically equivalent to the control autografts. Histology of the dermal matrix showed fibroblast infiltration, neovascularization, and neoepithelialization without evidence of rejection. Wound assessment over time showed that thin split-thickness autografts plus allograft dermal matrix were equivalent to thicker split-thickness autografts.
TL;DR: General area cladogram suggests the following area relationships: Pacific and Caribbean Central America are sister areas, Choco is the sister to the Central American area, and Amazonia/southeastern Brazil is the outgroup area to the Choco/Central American clade.
TL;DR: With the advent of soft tissue periodontal plastic procedures designed to enhance dentofacial harmony following the same basic tenets as those of the removable prosthodontist, the domain of periodontics has changed from being strictly a health service to one where smile enhancement has been brought to the forefront of treatment planning.
Abstract: Until recently, dentists’ and the public’s concept of dental aesthetics was necessarily limited to alterations of the teeth themselves. Dentists concerned themselves with changing the position, the shape and the color of the teeth basically restoring missing units or enhancing those already present. For the most part the dentist was forced to accept the pre-existing relationship between the three components of the smile; the teeth, the gingival scaffold and the lips. Interestingly, the restorative dentist’s concept of aesthetics varied considerably from that practiced by removable prosthodontists where, in the full denture set-up, they could not only select the most desirable shape and color of denture tooth concomitant with the patient’s facial features but could position them in the optimal relationship with regards to the upper lip, the lower lip and the commissures of the mouth thereby creating the desired ideal smile. The three basic tenets germaine to optimal aesthetics in removable prosthetics were not really a part of the restorative dentist’s rules, as any changes in the pre-existing lip-tooth-gingival relationships were thought to necessitate longterm orthodontic therapy, often in combination with orthognathic surgery or aggressive periodontal procedures. Today much of this has changed; with the advent of soft tissue periodontal plastic procedures designed to enhance dentofacial harmony following the same basic tenets as those of the removable prosthodontist. The domain of periodontics has changed from being strictly a health service to one where smile enhancement has been brought to the forefront of treatment planning. The essentials of a smile involve the relationships between the three primary components: the teeth lip framework the gingival scaffold.
Journal Article•
TL;DR: In this article, the authors present un certain nombre de donnees collectees, en 1990, concernant la criminalite aux Etats-Unis, examinent l'influence de la segregation residentielle and de l'isolement social dont est victime cette communaute.
Abstract: Les AA. montrent que la criminalite au sein de la communaute afro-americaine est un phenomene tres important. Ils s'efforcent d'isoler les facteurs qui contribuent a entretenir cette situation. Ils presentent un certain nombre de donnees collectees, en 1990, concernant la criminalite aux Etats-Unis. Ils examinent l'influence de la segregation residentielle et de l'isolement social dont est victime cette communaute. Ils montrent que cette situation induit un phenomene de marginalisation economique, culturelle et politique des populations afro-americaines
TL;DR: In the absence of iron, equimolar fluxes of NO and O interact to yield potent oxidants such as ONOO/ONOOH, which oxidize organic compounds.
TL;DR: Swimming in rivers, streams, or pools increased the odds of infection, as did using streams as a drinking water source, and children who had contact with sheep also had increased prevalence odds.
Abstract: In 1992, the authors studied Helicobacter pylori infection and exposures relevant to person-to-person, waterborne, foodborne, and zoonotic transmission in a census sample of 684 2-9-year-old children in Aldana, Narino, a rural community in the Colombian Andes. H. pylori prevalence, as determined by the 13C-urea breath test, was 69%, and prevalence increased from 53% in 2 year-olds to 87% in 9 year-olds. Beginning at 3 years of age, a higher percentage of males compared with females were infected. Odds ratios were estimated by multivariate logistic regression to control for mutual confounding by transmission-pathway proxy variables and socioeconomic indicators. Among transmission-pathway proxies, the strongest predictor of H. pylori status was the number of persons who lived in the home, with the number of children apparently being of greater importance than the number of adults. Swimming in rivers, streams, or pools increased the odds of infection, as did using streams as a drinking water source. Children who frequently consumed raw vegetables were more likely to have the infection, and children who had contact with sheep also had increased prevalence odds. Because the results did not implicate a single mode of transmission, the possibility of multiple pathways is indicated.
TL;DR: In this article, the effect of load and sliding velocity on the frictional behavior and graphitization process occurring in diamond-like carbon (DLC) films during wear was studied.
Abstract: In our recent studies, diamond-like carbon (DLC) films were found to possess low coefficient of friction (f < 0.1) and excellent wear resistance. The reduction in f was found to be consistent with wear-induced graphitization of the DLC structure. The purpose of the present work was to study the effect of load and sliding velocity on the frictional behavior and graphitization process occurring in DLC during wear. Pin-on-disc experiments were conducted on DLC-coated SiC substrates at sliding velocities between 0.06 and 1.6 m s−1 under 1 and 10 N loading levels using ZrO2 balls as the pin material. Analytical transmission electron microscopy was used to characterize the structure and microstructure of the wear debris after testing. The results showed that both sliding velocity and contact load influence the graphitization process. Higher sliding velocities increase the contact frequency and the rate of temperature rise that may facilitate the release of hydrogen atoms from the sp3 structure. Higher loading enhances shear deformation and transformation of the weakened hydrogen-depleted DLC structure into graphite [10]. The present findings are consistent with our earlier proposed wear-induced graphitization mechanism for these films. An equation was developed to describe the transformation kinetics of DLC into graphite as a function of sliding velocity and applied stress.
TL;DR: In this article, a single set of experiments was conducted to investigate the relative mobilities of many subduction zone volatiles and trace elements in hydrothermal fluids, and the experimental results demonstrate that the composition of slab-derived fluids has great implications for the recycling of elements; not only in arc magmas but also in mantle plumes.
TL;DR: It is suggested that P-selectin is constitutively expressed on vascular endothelium in some tissues of the mouse and that there are significant regional differences in the magnitude and time course of histamine- and endotoxin-induced P- selectin expression.
Abstract: A novel technique involving radiolabeled monoclonal antibodies was used to characterize and compare the expression of E- and P-selectin on unstimulated, histamine-challenged, and endotoxin-challenged endothelial cells in various tissues of the mouse. Under unstimulated conditions, E-selectin was absent in all organs, but significant expression of P-selectin was observed in several organs. Histamine induced a rapid time-dependent upregulation of P-selectin, with the largest responses observed in mesentery and lung. Significant fold elevations in P-selectin expression occurred as early as 5 minutes after the histamine injection and remained elevated up to 1 hour. Histamine-induced P-selectin upregulation was inhibited by the H1 receptor antagonist diphenhydramine, whereas the H2 receptor antagonist cimetidine had no effect. Endotoxin (lipopolysaccharide [LPS]) also induced a time-dependent expression of P-selectin that reached a maximum between 4 and 8 hours after endotoxin administration. LPS-induced upreg...
TL;DR: The synthesis, chemistry, and properties of curved-surface, polynuclear aromatics would be of great interest even if buckminsterfullerene had not been discovered as discussed by the authors.
Abstract: The synthesis, chemistry, and properties of curved-surface, polynuclear aromatics would be of great interest even if buckminsterfullerene had never been discovered. The presence of both convex and concave surfaces provides the potential for exceptional stereo-selectivities, as well as attractive opportunities for some very interesting metal complexation. However, the fullerenes have been discovered, and there can be no denying that this relationship adds an additional level of excitement to what is already an intriguing new class of aromatic compounds. 46 refs., 3 figs., 1 tab.
TL;DR: In this paper, the authors empirically examined differences between automatic and controlled processing by executives in an increasingly dynamic industry and found that cognitive inertia affects judgments in both modes, but the effect is stronger with automatic processing.
Abstract: The authors empirically examine differences between automatic and controlled processing by executives in an increasingly dynamic industry. The results suggest that cognitive inertia affects judgments in both modes, but the effect is stronger with automatic processing. Specifically, the authors conducted two studies examining executives' cognitive maps of competitive positioning. First, they explored differences in ways strategists categorize competitors in a cross-sectional field study conducted during a period of significant environmental upheaval. They found that managers relied on cognitive maps that reflected obsolete industry boundaries rather than configurations representative of the deregulated marketplace. Hence, managers must be mindful to incorporate new information proactively from many sources and to actively discard old, automatic maps in order to develop reliable maps for changing environments. In a second study, managerial competitive schemas of competitive positioning were compared longitudinally across three research projects conducted in the financial intermediary industry. An eight-year time frame provided a unique opportunity to explore the content of mental models in an industry undergoing an accelerating rate of change. The longitudinal results indicate that change creates diversity of thought across managers in the same environment. Managers at competing firms are therefore apt to view competition quite differently in turbulent environments. Implications of the study findings for strategic decision making, consensus and conflict, and organizational learning and executive succession in turbulent environments are discussed. Issues are identified that warrant further research.