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Fundamental Knowledge (fundamental + knowledge)
Selected AbstractsPressure,pain threshold determination in the oral mucosa: validity and reliabilityJOURNAL OF ORAL REHABILITATION, Issue 7 2002T. Ogimoto Fundamental knowledge of pain in the oral mucosa is lacking. We determined the validity and reliability of the pressure,pain threshold (PPT) measurement in the oral mucosa using a newly developed hand-held pressure algometer. Ten dentulous subjects were recruited, and the PPT was measured at the bilateral buccal (on the attached gingiva apical to the midline of the upper first premolars, 3 mm from the mucogingival junction) and the palatal sites (mid-point between the bilateral upper first molars). The PPT linearly increased with an increase in load-rate (P < 0·0001). The PPT yielded a high intra-individual stability both for the same-day consecutive trials and weekly sessions. The palatal site revealed a 4- to 4·65-fold greater PPT than the buccal sites (Bonferroni, P < 0·0001), whereas no difference was found between the bilateral buccal sites (P=0·663). Despite a great interindividual variation in the PPT, significant intra-individual correlations were found among the measurement sites. This suggested differences in individual sensitivity to pain in the oral mucosa, which may determine overall pain sensation specific to an individual. A pressure algometer described herein reliably assessed the PPT in the oral mucosa and sensitively discriminated PPT differences at different sites and at different load-rates, suggest-ing the reliability and validity of PPT measure-ments in the oral mucosa for clinical and research investigations. [source] Coffee and Cigarette Consumption and Perceived Effects in Recovering Alcoholics Participating in Alcoholics Anonymous in Nashville, TennesseeALCOHOLISM, Issue 10 2008Michael S. Reich Background:, Alcoholics Anonymous (AA) members represent an important and relatively understudied population for improving our understanding of alcohol dependence recovery as over 1 million Americans participate in the program. Further insight into coffee and cigarette use by these individuals is necessary given AA members' apparent widespread consumption and the recognized health consequences and psychopharmacological actions of these substances. Methods:, Volunteers were sought from all open-AA meetings in Nashville, TN during the summer of 2007 to complete a questionnaire (n = 289, completion rate = 94.1%) including timeline followback for coffee, cigarette, and alcohol consumption; the Alcoholics Anonymous Affiliation Scale; coffee consumption and effects questions; the Fagerstrom Test for Nicotine Dependence (FTND); and the Smoking Effects Questionnaire. Results:, Mean (±SD) age of onset of alcohol consumption was 15.4 ± 4.2 years and mean lifetime alcohol consumption was 1026.0 ± 772.8 kg ethanol. Median declared alcohol abstinence was 2.1 years (range: 0 days to 41.1 years) and median lifetime AA attendance was 1000.0 meetings (range: 4 to 44,209 meetings); average AA affiliation score was 7.6 ± 1.5. Most (88.5%) individuals consumed coffee and approximately 33% of coffee consumers drank more than 4 cups per day (M = 3.9 ± 3.9). The most common self-reported reasons for coffee consumption and coffee-associated behavioral changes were related to stimulatory effects. More than half (56.9%) of individuals in AA smoked cigarettes. Of those who smoked, 78.7% consumed at least half a pack of cigarettes per day (M = 21.8 ± 12.3). Smokers' FTND scores were 5.8 ± 2.4; over 60% of smokers were highly or very highly dependent. Reduced negative affect was the most important subjective effect of smoking. Conclusions:, A greater proportion of AA participants drink coffee and smoke cigarettes in larger per capita amounts than observed in general U.S. populations. The effects of these products as described by AA participants suggest significant stimulation and negative affect reduction. Fundamental knowledge of the quantitative and qualitative aspects of coffee and cigarette consumption among AA members will enable future research to discern their impact on alcohol abstinence and recovery. [source] Influence of alternansucrase-derived oligosaccharides and other carbohydrates on ,-galactosidase and ,-glucosidase activity in Bifidobacterium adolescentisLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2008S.M. Holt Abstract Aims:, To determine the influence of alternansucrase-derived oligosaccharides (AOS) and other carbohydrates on ,-galactosidase and ,-glucosidase activity in Bifidobacterium adolescentis. Methods and Results:, Activities for ,-galactosidase and ,-glucosidase were determined from cell extracts of B. adolescentis grown on 18 test carbohydrates including AOS. ,-galactosidase activity was enhanced on a variety of ,-linked or ,-linked carbohydrates regardless of a galactoside or glucoside. ,-glucosidase, however, was enhanced only on ,-linked carbohydrates. AOS significantly enhanced enzyme activity compared with most of the carbohydrates tested. Most of the AOS showed significant increases in activity for both enzymes over that displayed by their corresponding acceptor carbohydrates. Conclusions:, ,-galactosidase may serve as a biomarker for microbial metabolic activity within the large intestine for potential prebiotics composed of ,-linked or ,-linked oligosaccharides whereas ,-glucosidase activity may be restricted to assessing the influence of only ,-linked carbohydrates. The AOS synthesis process provided a value-added component to carbohydrates by increasing metabolic activity (via ,-galactosidase and ,-glucosidase) over certain acceptor carbohydrates. Significance and Impact of the Study:, Fundamental knowledge of enzyme activity in Bifidobacterium may aid in the design of more effective prebiotics and may also help identify enzyme indicators of metabolic activity when assessing influence within the intestine. [source] Quantitative structure-activity relationship methods: Perspectives on drug discovery and toxicologyENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2003Roger Perkins Abstract Quantitative structure,activity relationships (QSARs) attempt to correlate chemical structure with activity using statistical approaches. The QSAR models are useful for various purposes including the prediction of activities of untested chemicals. Quantitative structure,activity relationships and other related approaches have attracted broad scientific interest, particularly in the pharmaceutical industry for drug discovery and in toxicology and environmental science for risk assessment. An assortment of new QSAR methods have been developed during the past decade, most of them focused on drug discovery. Besides advancing our fundamental knowledge of QSARs, these scientific efforts have stimulated their application in a wider range of disciplines, such as toxicology, where QSARs have not yet gained full appreciation. In this review, we attempt to summarize the status of QSAR with emphasis on illuminating the utility and limitations of QSAR technology. We will first review two-dimensional (2D) QSAR with a discussion of the availability and appropriate selection of molecular descriptors. We will then proceed to describe three-dimensional (3D) QSAR and key issues associated with this technology, then compare the relative suitability of 2D and 3D QSAR for different applications. Given the recent technological advances in biological research for rapid identification of drug targets, we mention several examples in which QSAR approaches are employed in conjunction with improved knowledge of the structure and function of the target receptor. The review will conclude by discussing statistical validation of QSAR models, a topic that has received sparse attention in recent years despite its critical importance. [source] A genetic algorithm approach to solving the anti-covering location problemEXPERT SYSTEMS, Issue 5 2006Sohail S. Chaudhry Abstract: In this paper we address the problem of locating a maximum weighted number of facilities such that no two are within a specified distance from each other. A natural process of evolution approach, more specifically a genetic algorithm, is proposed to solve this problem. It is shown that through the use of a commercially available spreadsheet-based genetic algorithm software package, the decision-maker with a fundamental knowledge of spreadsheets can easily set up and solve this optimization problem. Also, we report on our extensive computational experience using three different data sets. [source] Integration of Density Multiplication in the Formation of Device-Oriented Structures by Directed Assembly of Block Copolymer,Homopolymer BlendsADVANCED FUNCTIONAL MATERIALS, Issue 8 2010Guoliang Liu Abstract Non-regular, device-oriented structures can be directed to assemble on chemically nanopatterned surfaces such that the density of features in the assembled pattern is multiplied by a factor of two or more compared to the chemical pattern. By blending the block copolymers with homopolymers and designing the chemical pattern rationally, complicated structures such as bends, jogs, junctions, terminations, and combined structures are fabricated. Previously, directed assembly of block copolymers has been shown to enhance the resolution of lithographic processes for hexagonal arrays of spots and parallel lines, corresponding to the bulk morphologies of block copolymer systems, but this is the first demonstration of enhanced resolution for more complicated, device-oriented features. This fundamental knowledge broadens the range of technologies that can be served by the directed assembly of block copolymers. [source] Commentary on "meeting the competency needs of global leaders: A partnership approach": An executive coach's perspectiveHUMAN RESOURCE MANAGEMENT, Issue 3 2006Judi Brownell This article concludes that common competencies, the fundamental knowledge and skills developed in traditional educational environments, are necessary but insufficient in the preparation of global leaders. Rather, human resource professionals, in partnership with management educators, are best positioned to identify and facilitate global leadership excellence by focusing on the identification and development of key personal characteristics or distinctive competencies. In particular, global leaders must be men and women of sound character. We further propose that "distinctive competencies" are best assessed through experience in the field. Recommendations are offered as to how competency-based leadership development can be designed to address both common and distinctive competencies, with special attention to the individual's character. © 2006 Wiley Periodicals, Inc. [source] Trehalose and trehalose-hydrolyzing enzyme in the haemolymph of Locusta migratoria infected with Metarhizium anisopliae strain CQMa102INSECT SCIENCE, Issue 4 2007HUA ZHAO Abstract Topical application of the Metarhizium anisopliae var. acridum specialist strain CQMa102 to the locust Locusta migratoria manilensis results in changes of the concentrations of trehalose and glucose in the haemolymph. Micrographs of the locust haemolymph shows Metarhizium anisopliae can effectivly penetrate the external skeleton of locust and after 2 days infection, the hyphae body will appear in the haemolymph of infected insects. The time in decrease of trehalose concentration coincided with that in increase of trehalose-hydrolysing enzyme activity in the haemolymph of the fungus-infected insects. Overlay gel analysis indicated there was considerably more trehalose-hydrolysing activity in the haemolymph of locusts infected by fungus than in controls. A comparable isoform was identified in in vitro culture of the fungus, suggesting a fungal origin for the in vivo enzyme. Haemolymph trehalose decreased significantly during mycosis of locusts by M. anisopliae. All these results suggested that this fungus may take advantage of competing nutrient utilization against the insect by its trehalose-hydrolyzing enzyme secretion. It may provide fundamental knowledge for fungal pathogenesis. [source] Treading on Tradition: Approaches to Teaching International Relations to the Nontraditional UndergraduateINTERNATIONAL STUDIES PERSPECTIVES, Issue 1 2002Nancy E. Wright Nontraditional undergraduates (NTUs), undergraduates who typically are older than average, work full-time, and/or are entrusted with substantial family responsibilities, pose a special challenge to international relations educators. Severe constraints on time and access to library facilities both impede progress and may give an erroneous impression that NTUs are not as committed to their education as more conventional college undergraduates. The lack of continuity in education that typifies the NTU experience often manifests itself in anxiety, frustration, and gaps in fundamental knowledge. At the same time, the maturity and sophistication that come with life experience often far exceed that of the more conventional college student. Furthermore, typical requirements of international relations and international studies majors, such as second and third language proficiency, internships with international organizations, and overseas study are often not feasible for the working student with family responsibilities. Possibilities for meeting the challenges of teaching NTUs include greater use of open-book examinations, research proposals, case studies, simulations, problem-based learning (PBL), use of the Internet, and the development of short-term intensive overseas study opportunities that accommodate the working student's schedule. [source] Optimization of an industrial afterburnerJOURNAL OF CHEMOMETRICS, Issue 1 2003Tomas Öberg Abstract An industrial afterburner was optimized using statistical experimental design. A computer-generated optimal design was adapted to domain constraints and previous knowledge about the experimental variables. Carbon monoxide was used as a general indicator for the operating conditions, and a reduced response surface model was fitted to the experimental data. In a second phase the initial results were verified and investigated in more detail with regard to chlorinated aromatics. The empirical models obtained were further interpreted using results from laboratory investigations and more fundamental knowledge from combustion theory. Copyright © 2003 John Wiley & Sons, Ltd. [source] Wet granulation in a twin-screw extruder: Implications of screw designJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 4 2010M.R. Thompson Abstract Wet granulation in twin-screw extrusion machinery is an attractive technology for the continuous processing of pharmaceuticals. The performance of this machinery is integrally tied to its screw design yet little fundamental knowledge exists in this emerging field for granulation to intelligently create, troubleshoot, and scale-up such processes. This study endeavored to systematically examine the influence of different commercially available screw elements on the flow behavior and granulation mechanics of lactose monohydrate saturated at low concentration (5,12%, w/w) with an aqueous polyvinyl-pyrrolidone binder. The results of the work showed that current screw elements could be successfully incorporated into designs for wet granulation, to tailor the particle size as well as particle shape of an agglomerate product. Conveying elements for cohesive granular flows were shown to perform similar to their use in polymer processing, as effective transport units with low specific mechanical energy input. The conveying zones provided little significant change to the particle size or shape, though the degree of channel fill in these sections had a significant influence on the more energy-intensive mixing elements studied. The standard mixing elements for this machine, kneading blocks and comb mixers, were found to be effective for generating coarser particles, though their mechanisms of granulation differed significantly. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 2090,2103, 2010 [source] Role of bacteria in the oviposition behaviour and larval development of stable fliesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 1 2006A. Romero Abstract., Stable flies, Stomoxys calcitrans (L.), are the most important pests of cattle in the United States. However, adequate management strategies for stable flies, especially for pastured cattle, are lacking. Microbial/symbiont-based approaches offer novel venues for management of insect pests and/or vector-borne human and animal pathogens. Unfortunately, the fundamental knowledge of stable fly,microbial associations and their effect on stable fly biology is lacking. In this study, stable flies laid greater numbers of eggs on a substrate with an active microbial community (> 95% of total eggs oviposited) than on a sterilized substrate. In addition, stable fly larvae could not develop in a sterilized natural or artificial substrate/medium. Bacteria were isolated and identified from a natural stable fly oviposition/developmental habitat and their individual effect on stable fly oviposition response and larval development was evaluated in laboratory bioassays. Of nine bacterial strains evaluated in the oviposition bioassays, Citrobacter freundii stimulated oviposition to the greatest extent. C. freundii also sustained stable fly development, but to a lesser degree than Serratia fanticola. Serratia marcescens and Aeromonas spp. neither stimulated oviposition nor supported stable fly development. These results demonstrate a stable fly bacterial symbiosis; stable fly larval development depends on a live microbial community in the natural habitat, and stable fly females are capable of selecting an oviposition site based on the microbially derived stimuli that indicate the suitability of the substrate for larval development. This study shows a promising starting point for exploiting stable fly,bacterial associations for development of novel approaches for stable fly management. [source] Polymerization and Sickle Cell Disease: A Molecular ViewMICROCIRCULATION, Issue 2 2004FRANK A. FERRONE ABSTRACT The present molecular-level understanding of polymerization and sickling is reviewed for 2 central questions in sickle hemoglobin pathophysiology, viz., what determines when cells sickle, and what determines when cells get stuck. The description of sickling includes the central aspects of the double nucleation mechanism, as well as recent results on the effects of crowding, with an emphasis on the physiological applicability of this fundamental knowledge. In considering when cells get stuck, new measurements of individual fiber stiffness and the processes of depolymerization are also considered. Finally, a fundamental connection is shown between thermodynamics and rheology. [source] The protein secretory pathway of Candida albicansMYCOSES, Issue 4 2009William A. Fonzi Summary Virulence of the opportunistic pathogen, Candida albicans, relies on an assemblage of attributes. These include the secretion of hydrolytic enzymes, cell surface adhesins, morphological transition between yeast and hyphae, phenotypic switching and biofilm formation. These diverse features are united by their dependence on the protein secretory apparatus for expression. Although the secretory apparatus of C. albicans has been studied limitedly, it appears to conform to the well-conserved eukaryotic system of vesicle-mediated transport between intracellular compartments and the cell surface. Genome comparison with Saccharomyces cerevisiae, however, shows multiple differences whose functional significance is yet unstudied. A unique aspect of the secretory pathway of C. albicans is its structural, and perhaps functional, rearrangement in hyphal vs. yeast cells. This, and evidence of non-conserved secretion mechanism(s), suggest that there is much fundamental knowledge to be derived from the analysis of secretion in C. albicans, which will be relevant to its ability to cause disease. [source] Effects of Viscous Dissipation on Heat Transfer between an Array of Long Circular Cylinders and Power Law FluidsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 6 2007R. P. Chhabra Abstract The free surface model has been combined with the equations of motion and of thermal energy to investigate the role of viscous dissipation on heat transfer between banks of long cylinders and power law (shear-thinning and shear-thickening) fluids. The equations of motion cast in the stream function/vorticity formulation have been solved numerically using a second-order accurate finite difference method to obtain extensive information on the behaviour of local and surface-averaged Nusselt numbers over a range of Reynolds numbers 1 , 500, for a wide range of power law indices (0.4 , n , 2.0), Brinkman numbers (0 , Br , 5) and Prandtl numbers (Pr = 1, 1000) at two representative solid volume fractions corresponding to the porosities of e = 0.4 and 0.9. Two different thermal boundary conditions are considered at the cylinder surface: constant temperature (CT) and constant heat flux (CHF). The results presented herein provide a fundamental knowledge about the influence of viscous dissipation on the heat transfer characteristics. The results reported herein further show that the effect of Brinkman number on heat transfer is strongly conditioned by the thermal boundary condition, Prandtl number and the power law index. On a combiné le modèle de surface libre aux équations de mouvement et de transfert de chaleur afin d'étudier le rôle de la dissipation visqueuse sur le transfert de chaleur entre des rangées de cylindres longs pour des fluides de loi de puissance (rhéofluidifiants et rhéoépaississants). Les équations de mouvement formulées en fonction de courant/vorticité ont été résolues numériquement à l'aide d'une méthode de différences finies du second ordre, afin d'obtenir des informations détaillées sur le comportement des nombres de Nusselt locaux et moyennés en surface pour une gamme de nombres de Reynolds compris entre 1 et 500, une large gamme d'indices de loi de puissance (0,4 , n , 2,0), de nombres de Brinkman (0 , Br , 5) et de nombres de Prandtl (Pr = 1,1000) à deux fractions de volume de solides correspondant à une porosité de e = 0,4 et 0,9. Deux conditions aux limites thermiques ont été considérées à la surface du cylindre: la température constante (CT) et le flux de chaleur constant (CHF). Les résultats présentés permettent de rendre compte de l'influence de la dissipation visqueuse sur les caractéristiques du transfert de chaleur et l'effet du nombre de Brinkman sur le transfert de chaleur qui est fortement influencé par la condition aux limites thermique, le nombre de Prandtl et l'indice de loi de puissance. [source] Platform biochemicals for a biorenewable chemical industryTHE PLANT JOURNAL, Issue 4 2008Basil J. Nikolau Summary The chemical industry is currently reliant on a historically inexpensive, petroleum-based carbon feedstock that generates a small collection of platform chemicals from which highly efficient chemical conversions lead to the manufacture of a large variety of chemical products. Recently, a number of factors have coalesced to provide the impetus to explore alternative renewable sources of carbon. Here we discuss the potential impact on the chemical industry of shifting from non-renewable carbon sources to renewable carbon sources. This change to the manufacture of chemicals from biological carbon sources will provide an opportunity for the biological research community to contribute fundamental knowledge concerning carbon metabolism and its regulation. We discuss whether fundamental biological research into metabolic processes at a holistic level, made possible by completed genome sequences and integrated with detailed structural understanding of biocatalysts, can change the chemical industry from being dependent on fossil-carbon feedstocks to using biorenewable feedstocks. We illustrate this potential by discussing the prospect of building a platform technology based upon a concept of combinatorial biosynthesis, which would explore the enzymological flexibilities of polyketide biosynthesis. [source] | ||||||||||||||||