Showing papers by "West Virginia University published in 2002"

Encouraging Knowledge Sharing: The Role of Organizational Reward Systems

Abstract: This article examines the role of monetary rewards in encouraging knowledge sharing in organizations through four mechanisms of knowledge sharing. We argue that the system of contributing knowledge to databases is the most amenable to rewards contingent on knowledge sharing behaviors because of opportunities for the reward allocator to measure the knowledge sharing behaviors. In the case of formal interactions within or across teams and work units, while rewards could be made partly contingent on knowledge sharing behaviors as in merit pay, rewards based on collective performance are also likely to be effective in creating a feeling of cooperation, ownership, and commitment among employees. In addition, we propose that team-based rewards and company wide incentives (profit sharing, gainsharing, and employee stock options) would be particularly instrumental in enhancing knowledge sharing within teams and across work units, respectively. In the case of knowledge sharing through informal interactions, the ke...

Fiber-Reinforced Polymer Composites for Construction—State-of-the-Art Review

Abstract: A concise state-of-the-art survey of fiber-reinforced polymer (also known as fiber-reinforced plastic) composites for construction applications in civil engineering is presented. The paper is organized into separate sections on structural shapes, bridge decks, internal reinforcements, externally bonded reinforcements, and standards and codes. Each section includes a historical review, the current state of the art, and future challenges.

Board Characteristics and Audit Fees

Abstract: This paper examines the relations between three board characteristics (independence, diligence, and expertise) and Big 6 audit fees for Fortune 1000 companies. To protect its reputation capital, avoid legal liability, and promote shareholder interests, a more independent, diligent, and expert board may demand differentially higher audit quality (greater assurance, which requires more audit work) than the Big 6 audit firms normally provide. The audit fee increases as the auditor's additional costs are passed on to the client, such that we expect positive relations between audit fees and the board characteristics examined. We find significant positive relations between audit fees and board independence, diligence, and expertise. The results persist when similar measures of audit committee “quality” are included in the model. The results add to the growing body of literature documenting relations between corporate governance mechanisms and various facets of the financial reporting and audit processes, as well as to our understanding of the determinants of audit fees.

Micronutrients in Crop Production

Abstract: The essential micronutrients for field crops are B, Cu, Fe, Mn, Mo, and Zn. Other mineral nutrients at low concentrations considered essential to growth of some plants are Ni and Co. The incidence of micronutrient deficiencies in crops has increased markedly in recent years due to intensive cropping, loss of top soil by erosion, losses of micronutrients through leaching, liming of acid soils, decreased proportions of farmyard manure compared to chemical fertilizers, increased purity of chemical fertilizers, and use of marginal lands for crop production. Micronutrient deficiency problems are also aggravated by the high demand of modern crop cultivars. Increases in crop yields from application of micronutrients have been reported in many parts of the world. Factors such as pH, redox potential, biological activity, SOM, cation-exchange capacity, and clay contents are important in determining the availability of micronutrients in soils. Plant factors such as root and root hair morphology (length, density, surface area), root-induced changes (secretion of H + , OH − , HCO 3 − ), root exudation of organic acids (citric, malic, tartaric, oxalic, phenolic), sugars, and nonproteinogenic amino acids (phytosiderophores), secretion of enzymes (phosphatases), plant demand, plant species/cultivars, and microbial associations (enhanced CO 2 production, rhizobia, mycorrhizae, rhizobacteria) have profound influences on plant ability to absorb and utilize micronutrients from soil. The objectives of this article are to report advances in research on the micronutrient availability and requirements for crops, in correcting deficiencies and toxicities in soils and plants, and in increasing the ability of plants to acquire needed amounts of micronutrient elements.

Nutritional approaches to combat oxidative stress in Alzheimer's disease.

Abstract: Alzheimer's disease (AD) brains are characterized by extensive oxidative stress. Additionally, large depositions of amyloid -peptide (A) are observed, and many researchers opine that A is central to the pathogenesis of AD. Our laboratory combined these two observations in a comprehensive model for neurodegeneration in AD brains centered around A-induced oxidative stress. Given the oxidative stress in AD and its potentially important role in neurodegeneration, considerable research has been conducted on the use of antioxidants to slow or reverse the pathology and course of AD. One source of antioxidants is the diet. This review examines the literature of the effects of endogenous and exogenous, nutritionally-derived antioxidants in relation to AD. In particular, studies of glutathione and other SH-containing antioxidants, vitamins, and polyphenolic compounds and their use in AD and modulation of A-induced oxidative stress and neurotoxicity are reviewed. © 2002 Elsevier Science Inc. All rights reserved.

The Political Economy of FEMA Disaster Payments

Abstract: A central contribution of public choice theory to the analysis of government activity is in viewing the activities of government, not as determined by some single altruistic dictator, but rather as the result of a process involving individual political agents who react to the incentives they face. Federal disaster relief, administered by the Federal Emergency Management Agency (FEMA), is one activity that is ripe for political influence due to the process of disaster declaration and relief. After a disaster strikes a particular state, the governor makes a request to the president for disaster assistance. Following a governor’s request, the president then decides whether to declare the state or region a disaster area. Only after a disaster has been declared by the president can disaster relief be given. FEMA is in charge of determining the level of relief funding for the area, but additional appropriations are determined by congress in cases requiring large amounts of funding beyond FEMA’s allocated budget. The Act which governs the rules of federal disaster declaration and expenditures gives the president the authority to declare a disaster without the approval of congress.

Communication delays in wide area measurement systems

Abstract: This paper provides a tutorial introduction to phasor measurement units (PMU) when applied in a power system environment, provides an overview of communication alternatives for wide area measurement systems (WAMS), and computes the delay budget for each type of communication link. The goal of this study is to provide data regarding the communication delay that can be incorporated into the analysis and simulation of WAMS.

Large‐eddy simulation of the diurnal cycle of shallow cumulus convection over land

Abstract: SUMMARY Large-eddy simulations of the development of shallow cumulus convection over land are presented. Many characteristics of the cumulus layer previously found in simulations of quasi-steady convection over the sea are found to be reproduced in this more strongly forced, unsteady case. Furthermore, the results are shown to be encouragingly robust, with similar results obtained with eight independent models, and also across a range of numerical resolutions. The datasets produced are already being used in the development and evaluation of parametrizations used in numerical weather-prediction and climate models.

The geometry of reaction dynamics

Abstract: The geometrical structures which regulate transformations in dynamical systems with three or more degrees of freedom (DOFs) form the subject of this paper. Our treatment focuses on the (2n − 3)-dimensional normally hyperbolic invariant manifold (NHIM) in nDOF systems associated with a centre × · ·· ×centre × saddle in the phase space flow in the (2n − 1)dimensional energy surface. The NHIM bounds a (2n − 2)-dimensional surface, called a ‘transition state’ (TS) in chemical reaction dynamics, which partitions the energy surface into volumes characterized as ‘before’ and ‘after’ the transformation. This surface is the long-sought momentum-dependent TS beyond two DOFs. The (2n − 2)-dimensional stable and unstable manifolds associated with the (2n − 3)-dimensional NHIM are impenetrable barriers with the topology of multidimensional spherical cylinders. The phase flow interior to these spherical cylinders passes through the TS as the system undergoes its transformation. The phase flow exterior to these spherical cylinders is directed away from the TS and, consequently, will never undergo the transition. The explicit forms of these phase space barriers can be evaluated using normal form theory. Our treatment has the advantage of supplying a practical algorithm, and we demonstrate its use on a strongly coupled nonlinear Hamiltonian, the hydrogen atom in crossed electric and magnetic fields.

Characterizaton of short isoforms of the leptin receptor in rat cerebral microvessels and of brain uptake of leptin in mouse models of obesity.

Abstract: Leptin deficiency causes obesity in rodents and humans, but circulating levels of leptin are paradoxically elevated in obesity. The mechanisms underlying this leptin resistance are unknown, but may involve reduced leptin transport across the blood-brain barrier via short isoforms of the leptin receptor (Ob-R). Here, we first quantified short Ob-R mRNA expression in isolated rat cerebral microvessels constituting the blood-brain barrier and found that Ob-Ra and Ob-Rc mRNA were abundantly expressed in similar amounts. Second, brain uptake of leptin was reduced in mice lacking Ob-R. Third, brain uptake of leptin in New Zealand Obese mice, a strain that responds to central, but not peripheral, leptin, was reduced, suggesting that their obesity is at least partly due to deficient leptin transport into the brain. Fourth, brain uptake of leptin was significantly reduced in diet-induced obese mice. Neither New Zealand Obese mice nor diet-induced obese mice exhibited significant decreases in Ob-R mRNA expression in isolated cerebral microvessels. These data support the ideas that short isoforms of Ob-R are involved in brain uptake of leptin and that impaired blood-brain barrier function contributes to the pathogenesis of obesity. However, the mechanisms by which obesity-related deficits in brain uptake of leptin occur remain to be defined.

Genetics of Motility and Chemotaxis of a Fascinating Group of Bacteria: The Spirochetes

Abstract: Spirochetes are a medically important and ecologically significant group of motile bacteria with a distinct morphology. Outermost is a membrane sheath, and within this sheath is the protoplasmic cell cylinder and subterminally attached periplasmic flagella. Here we address specific and unique aspects of their motility and chemotaxis. For spirochetes, translational motility requires asymmetrical rotation of the two internally located flagellar bundles. Consequently, they have swimming modalities that are more complex than the well-studied paradigms. In addition, coordinated flagellar rotation likely involves an efficient and novel signaling mechanism. This signal would be transmitted over the length of the cell, which in some cases is over 100-fold greater than the cell diameter. Finally, many spirochetes, including Treponema, Borrelia, and Leptospira, are highly invasive pathogens. Motility is likely to play a major role in the disease process. This review summarizes the progress in the genetics of motility and chemotaxis of spirochetes, and points to new directions for future experimentation.

Wavelet Algorithms for High-Resolution Image Reconstruction

Abstract: High-resolution image reconstruction refers to the reconstruction of high-resolution images from multiple low-resolution, shifted, degraded samples of a true image. In this paper, we analyze this problem from the wavelet point of view. By expressing the true image as a function in ${\cal L}({\Bbb R}^2)$, we derive iterative algorithms which recover the function completely in the ${\cal L}$ sense from the given low-resolution functions. These algorithms decompose the function obtained from the previous iteration into different frequency components in the wavelet transform domain and add them into the new iterate to improve the approximation. We apply wavelet (packet) thresholding methods to denoise the function obtained in the previous step before adding it into the new iterate. Our numerical results show that the reconstructed images from our wavelet algorithms are better than that from the Tikhonov least-squares approach. Extension to super-resolution image reconstruction, where some of the low-resolution images are missing, is also considered.

Atypical Kinetic Profiles in Drug Metabolism Reactions

Abstract: The cytochrome P450 enzymes are involved in the biotransformation of both xenobiotic and endobiotic hydrophobic compounds, implicated in the bioactivation of certain procarcinogens (e.g., benzo[ a ]pyrene), and responsible for many metabolism-based drug-drug interactions ([Wrighton and Stevens, 1992

The Effectiveness of Interventions To Promote Mammography among Women with Historically Lower Rates of Screening

Abstract: This study examines mammography-enhancing intervention studies that focus on women in groups with historically lower rates of mammography use than the general population. These groups consist of women who are disproportionately older, poorer, of racial-ethnic minorities, have lower levels of formal education, and live in rural areas. We refer to them as diverse populations. The purpose of this report is to determine which types of mammography-enhancing interventions are most effective for these diverse populations. For this report, United States and international studies with concurrent controls that reported actual receipt of mammograms (usually based on self-report) as an outcome were eligible for inclusion. Intervention effects were measured by differences in intervention and control group screening rates postintervention and were weighted to reflect the certainty of each study's contribution. These effects differed significantly (Q = 218, 34 df), and the variation between studies was best explained by indicators of the use of access-enhancing approaches. Combined intervention effects were estimated for different categories of intervention types using random effects models for subgroups of studies. The strongest combination of approaches used access-enhancing and individual-directed strategies and resulted in an estimated 27% increase in mammography use (95% confidence interval, 9.9-43.9, nine studies). Additionally impressive was the access-enhancing and system-directed combination (20% increase and 95% confidence interval, 8.2-30.6, five studies). Access-enhancing strategies are an important complement to individual- and system-directed interventions for women with historically lower rates of screening.

Classroom justice: Perceptions of fairness as a predictor of student motivation, learning, and aggression

Abstract: The present study examined the relationship between students’ perceptions of distributive and procedural justice in a college course and student motivation concerning the course, affective learning in the course, and aggression toward the course instructor. Although student perceptions of both distributive and procedural justice were positively correlated with student motivation and affective learning and negatively correlated with student aggression toward the course instructor, multiple regression analyses indicated that only perceptions of procedural justice predicted the three criterion variables at a statistically significant level while distributive justice perceptions did not. Implications and suggestions for future research in classroom justice are offered.

Does a critical mass exist? A comparative analysis of women's legislative representation since 1950

Abstract: . It has often been argued theoretically that a ‘critical mass,’ ranging from 10 to 35 per cent women, is needed before major changes in legislative institutions, behaviour, policy priorities and policy voting occurs. This paper examines one of the less-explored dimensions of the critical mass concept: Is there a process by which women reaching a critical mass of the legislature accelerates the election of further women? Using data from the Inter-Parliamentary Union and International Institute for Democracy and Electoral Assistance, we analyze this question for 20 industrialized democracies over a period of half a century, longer than any other relevant research. Descriptive results indicate that gains in women's representation have been incremental rather than a critical mass accelerating the election of women to legislatures. In a multivariate analysis of the percentage of women in the lower house of the legislature, the critical mass is tested against established explanations of women's gains in seats: institutional rules, egalitarian political culture, political parties and economic development. Of two measures of the critical mass theory, one has no impact and the second results in only a small increase in women's gains. Far from being clearly demonstrated, critical mass theories need empirical testing.

The relations of anxiety sensitivity, experiential avoidance, and alexithymic coping to young adults' motivations for drinking.

Abstract: The authors examined whether motivations for drinking alcohol are associated with the anxiety-related dispositional tendencies of anxiety sensitivity, experiential avoidance, and alexithymic coping. The authors administered the Anxiety Sensitivity Index, Experiential Avoidance Scale, 20-item Toronto Alexithymia Scale, Revised Drinking Motives Questionnaire, and a demographics questionnaire to 182 university drinkers. In multiple regressions, the dispositional factors significantly predicted the risky drinking motives of coping, enhancement, and conformity. Coping and enhancement motives were significantly predicted by experiential avoidance. Conformity motives were significantly and independently predicted by anxiety sensitivity and alexithymia. The process of experiential avoidance mediated the bivariate correlation between anxiety sensitivity and coping-motivated drinking to a greater extent than did the process of alexithymic coping. The authors discuss the observed relations in regard to the psychological functions of drinking behavior that may portend the development of heavy drinking and alcohol problems in dispositionally vulnerable individuals. They also review implications for refinements of behavior therapy for problem drinkers.

Evaluation of anesthesia residents using mannequin-based simulation: a multiinstitutional study.

Abstract: BackgroundAnesthesia simulators can generate reproducible, standardized clinical scenarios for instruction and evaluation purposes. Valid and reliable simulated scenarios and grading systems must be developed to use simulation for evaluation of anesthesia residents.MethodsAfter obtaining Human Subje

Clinicopathological features of genetically confirmed Danon disease

Abstract: Background : Danon disease is due to primary deficiency of lysosome-associated membrane protein-2. Objective : To define the clinicopathologic features of Danon disease. Methods : The features of 20 affected men and 18 affected women in 13 families with genetically confirmed Danon disease were reviewed. Results : All patients had cardiomyopathy, 18 of 20 male patients (90%) and 6 of 18 female patients (33%) had skeletal myopathy, and 14 of 20 male patients (70%) and one of 18 female patients (6%) had mental retardation. Men were affected before age 20 years whereas most affected women developed cardiomyopathy in adulthood. Muscle histology revealed basophilic vacuoles that contain acid phosphatase–positive material within membranes that lack lysosome-associated membrane protein-2. Heart transplantation is the most effective treatment for the otherwise lethal cardiomyopathy. Conclusions : Danon disease is an X-linked dominant multisystem disorder affecting predominantly cardiac and skeletal muscles.

DksA Affects ppGpp Induction of RpoS at a Translational Level

Abstract: The RpoS sigma factor (also called σS or σ38) is known to regulate at least 50 genes in response to environmental sources of stress or during entry into stationary phase. Regulation of RpoS abundance and activity is complex, with many factors participating at multiple levels. One factor is the nutritional stress signal ppGpp. The absence of ppGpp blocks or delays the induction of rpoS during entry into stationary phase. Artificially inducing ppGpp, without starvation, is known to induce rpoS during the log phase 25- to 50-fold. Induction of ppGpp is found to have only minor effects on rpoS transcript abundance or on RpoS protein stability; instead, the efficiency of rpoS mRNA translation is increased by ppGpp as judged by both RpoS pulse-labeling and promoter-independent effects on lacZ fusions. DksA is found to affect RpoS abundance in a manner related to ppGpp. Deleting dksA blocks rpoS induction by ppGpp. Overproduction of DksA induces rpoS but not ppGpp. Deleting dksA neither alters regulation of ppGpp in response to amino acid starvation nor nullifies the inhibitory effects of ppGpp on stable RNA synthesis. Although this suggests that dksA is epistatic to ppGpp, inducing ppGpp does not induce DksA. A dksA deletion does display a subset of the same multiple-amino-acid requirements found for ppGpp0 mutants, but overproducing DksA does not satisfy ppGpp0 requirements. Sequenced spontaneous extragenic suppressors of dksA polyauxotrophy are frequently the same T563P rpoB allele that suppresses a ppGpp0 phenotype. We propose that DksA functions downstream of ppGpp but indirectly regulates rpoS induction.

Burnout and compassion fatigue among hospice caregivers.

Abstract: Burnout is a word currently used in discussions about the present nursing shortage. Hospice staff, because of their work with the terminally ill, are considered a high-risk group for burnout. Too frequently, the reason behind the decision to leave or take a sabbatical from hospice work is that the staff member reached the limits of his or her capacity to care and “couldn’t take it any more.” It is, therefore, important to discuss the concept of burnout and how it can affect hospice staff as well as the primary caregivers for hospice patients to ascertain the reasons behind it and take steps to lessen caregiver stress.

Reexamining the Role of Recasts in Native-Speaker/Nonnative-Speaker Interactions

Abstract: This study examines the occurrence and use of recasts in adult native-speaker/nonnative-speaker interactions in a nonclassroom setting. The study focuses on native-speaker recasts in three types of negotiations: one-signal negotiated interactions, extended negotiated interactions (Pica, 1988), and nonnegotiated interactions, and on recasts in response to nonnative speaker levels of grammaticality (single vs. multiple errors) resulting from four conversation tasks. The results show that recasts occur in different patterns than those reported in earlier research, but that these recasts are nevertheless used at rates consistent with previous research. These findings raise questions concerning current criteria for determining the existence of negative evidence in patterns that can be used by learners.

Design and Control of Wave Propagation Patterns in Excitable Media

Abstract: Intricate patterns of wave propagation are exhibited in a chemical reaction-diffusion system with spatiotemporal feedback. Wave behavior is controlled by feedback-regulated excitability gradients that guide propagation in specified directions. Waves interacting with boundaries and with other waves are observed when interaction terms are incorporated into the control algorithm. Spatiotemporal feedback offers wide flexibility for designing and controlling wave behavior in excitable media.