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Coefficient Values (coefficient + value)
Kinds of Coefficient Values Selected AbstractsA NUMERICAL APPROACH WITH VARIABLE TEMPERATURE BOUNDARY CONDITIONS TO DETERMINE THE EFFECTIVE HEAT TRANSFER COEFFICIENT VALUES DURING BAKING OF COOKIESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2006EREN DEMIRKOL ABSTRACT The increasing trade of ready-to-eat foods such as cookies highlights an interest in quality defects during baking. Heat (h and thermal diffusivity) and mass (mass transfer and diffusion coefficients) transfer parameters are significant parameters affecting the quality changes. Therefore, it is important to determine these parameters for modeling and process optimization studies. Among these, the h is important, revealing the relationship between the heating medium and product surface. As baking involves a simultaneous heat and mass transfer involving moisture diffusion and heat conduction inside and convective heat and mass transfer outside, a lumped system method may not be an accurate choice to determine the h value. Changes in the product volume and contact heating from bottom of the product also bring extra challenges to the determination of h. Therefore, the objective of this study was to use realistic approaches including simultaneous heat and mass transfer to determine the changes in h. The heffvalues for the bottom and top surface of the cookies were then determined, applying a numerical procedure where the surface temperature changes were the boundary conditions with evaporation on the surface. The hband ht values increased with baking temperature and varied with baking time. The results of this study showed that evaporative mass flux for the top surface, heat flux for the bottom surface and the product's volume changes were significant in the variation of h values. [source] Translation and validation of a Chinese language version of the Early Childhood Oral Health Impact Scale (ECOHIS)INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 6 2009GILLIAN H. M. LEE Objective., This study aimed to adapt the Early Childhood Oral Health Impact Scale (ECOHIS) for pre-school children in a Chinese speaking community and to investigate its psychometric properties (validity and reliability). Methods., A Chinese language version of the ECOHIS was derived through a forward,backward translation and tested for face and content validity among a focus group. A convenient sample of pre-school children (n = 111) was recruited (including a sub-sample with early childhood caries and caries-free children). Parents of the children self-completed the derived Chinese-ECOHIS measure. Validity of the measure was assessed by investigating the relationship between dental caries status and Chinese-ECOHIS scores (construct and criterion validity). A sub-sample of the parents repeated the ratings of the measure to enable reliability assessments. Both internal and test,retest reliability were determined. Results., A Chinese version of ECOHIS was derived with minor modification to the original version. Chinese-ECOHIS scores were associated with children's caries experience (dmft) (r = 0.66, P < 0.05) supporting convergent validity. In addition, variations in ECOHIS scores were apparent with respect to caries and caries-free groups (P < 0.001), supporting the ability to distinguish between patient groups. Cronbach's alpha values (internal reliability) for total ECOHIS score were 0.91 and intraclass correlation coefficient value (test,retest reliability) was 0.64. Conclusions., A Chinese version of the ECOHIS was developed and demonstrated acceptable validity and reliability. These findings can enable assessments of pre-school child oral health-related quality of life in Chinese speaking communities. [source] Psychometric attributes of the SCOPA-COG Brazilian versionMOVEMENT DISORDERS, Issue 1 2008Francisco Javier Carod-Artal MD Abstract Cross-cultural adaptation and independent psychometric assessment of the Scales for Outcomes in Parkinson's disease-Cognition (SCOPA-COG), Brazilian version was performed. Parkinson's disease (PD) patients were evaluated by means of the SCOPA-Motor scale, Hoehn and Yahr staging (HY), Clinical Impression of Severity Index-PD (CISI-PD), Parkinson Psychosis Rating Scale, and Hospital Anxiety and Depression Scale. Cognition was evaluated using the Mini-Mental State Examination (MMSE), Short Portable Mental Status Questionnaire (SPMSQ), and SCOPA-COG. The following attributes were explored: acceptability, scaling assumptions, reliability, precision, and construct validity. One hundred fifty-two patients were assessed (mean age, 63.2 years; disease duration, 7.8 years; median HY stage, 3). Mean SCOPA-COG and MMSE were 18.2 and 25.7, respectively. The internal consistency of the SCOPA-COG (Cronbach's alpha = 0.81; item-total correlation, 0.38,0.62) was satisfactory. While the intraclass correlation coefficient value was 0.80, weighted kappa ranged from 0.30 (dice task) to 0.72 (animal fluency task). The standard error of measurement value for the SCOPA-COG was 3.2, whereas the smallest real difference was 8.9. SCOPA-COG total scores significantly decreased as the HY stage increased (Kruskal-Wallis, P < 0.0001). Age, years of education, and PD duration (all, P < 0.001) were observed to have an independent, significant effect on the SCOPA-COG. The SCOPA-COG is a short, reliable, valid instrument that is sensitive to cognitive deficits specific to PD. © 2007 Movement Disorder Society [source] Homogeneous and inhomogeneous linewidth broadening of single polar GaN/AlN quantum dotsPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue S2 2009F. Demangeot Abstract We report on the dependence on temperature of the homogeneous and inhomogeneous broadening of the fundamental transition of single polar GaN/AlN quantum dots (QDs). Stranski-Krastanov QDs have been grown by molecular beam epitaxy using NH3 as a nitrogen source, with a very low surface density. Low temperature (LT) microphotoluminescence measurements have been performed on 200 nm wide mesas in order to isolate the luminescence of single QDs. The linewidth is found to vary from 590 ,eV at 4 K up to 1350 ,eV at 65 K in a dot of 6 monolayer height. Though the LT linewidth is still dominated by spectral diffusion, the temperature dependent broadening up to 50 K is mainly accounted for by interactions between excitons and acoustic phonons through a coupling coefficient value nearly two orders of magnitude larger than its counterpart in InAs QDs. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Crystallization and preliminary X-ray crystallographic analysis of free methionine-(R)-sulfoxide reductase from Staphylococcus aureusACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 11 2009Seoung Min Bong Free methionine-(R)-sulfoxide reductase (fRMsr) catalyzes the reduction of the free form of methionine-(R)-sulfoxide back to free methionine. The fRMsr protein from Staphylococcus aureus was overexpressed in Escherichia coli, purified and crystallized at 295,K using ammonium sulfate as a precipitant. Diffraction data were collected to 1.7,Å resolution from a native crystal using synchrotron radiation. The crystal belonged to the hexagonal space group P6122, with unit-cell parameters a = b = 89.84, c = 88.75,Å, , = , = 90, , = 120°. Assuming the presence of one molecule in the asymmetric unit, the calculated Matthews coefficient value was 2.21,Å3,Da,1, with a solvent content of 57.1%. [source] Development of an Estimation Procedure for an Activity-Based Travel Demand ModelCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 7 2008W. Recker The method uses a genetic algorithm to estimate coefficient values of the utility function, based on a particular multidimensional sequence alignment method to deal with the nominal, discrete attributes of the activity/travel pattern (e.g., which household member performs which activity, which vehicle is used, sequencing of activities), and a time sequence alignment method to handle temporal attributes of the activity pattern (e.g., starting and ending time of each activity and/or travel). The estimation procedure is tested on data drawn from a well-known activity/travel survey. [source] Automated classification of crystallization experiments using wavelets and statistical texture characterization techniquesJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2008D. Watts A method is presented for the classification of protein crystallization images based on image decomposition using the wavelet transform. The distribution of wavelet coefficient values in each sub-band image is modelled by a generalized Gaussian distribution to provide discriminatory variables. These statistical descriptors, together with second-order statistics obtained from joint probability distributions, are used with learning vector quantization to classify protein crystallization images. [source] Perceptions of Professionalism: Interior Design Practitioners Working for the Top 100 FirmsJOURNAL OF INTERIOR DESIGN, Issue 1 2001Craig Birdsong M.S. ABSTRACT A necessary gauge of a profession is its members' commitment to the components of a profession. This study examined interior design practitioners' perceptions of selected components. Interior designers employed by the top 100 firms identified in Interior Design magazine were surveyed about their perceptions of accreditation of undergraduate programs, state licensing, the NCIDQ examination, research and graduate education. Ninety-four (94) responses representing 34 firms were analyzed using frequencies, percentages, and mean scores. Spearman rho correlation coefficients were calculated to determine relationships and Horowitz's categorizations and descriptions of coefficient values were used for summarizing the Spearman correlation coefficients. In general, practitioners perceived an advantage of most components of a profession for interior design. Graduate education was the one professional component they did not view as important or advantageous as the other four. Practitioners might consider increased involvement in the various components interior design has developed to meet the requirements of a profession and acquire additional credentials for themselves. Educators and the professional organizations must work more diligently to help practitioners understand the importance of graduate education and its relevance to the continuing and successful growth of the profession. [source] Mechanism studies on CVD of boron carbide from a gas mixture of BCL3, CH4, and H2 in a dual impinging-jet reactorAICHE JOURNAL, Issue 3 2009Mustafa Karaman Abstract Nearly pure boron carbide free from impurities was produced on a tungsten substrate in a dual impinging-jet chemical vapor deposition reactor from a BCl3, CH4, and H2 mixture. The Fourier Transform Infrared (FTIR) analysis proved the formation of reaction intermediate BHCl2, which is proposed to occur mainly in the gaseous boundary layer next to the substrate surface. Among a large number of reaction mechanisms proposed only the ones considering the molecular adsorption of boron carbide on the substrate surface gave reasonable fits. In the proposed mechanism dichloroborane is formed in the gas phase only as a by-product. Boron carbide, on the other hand, is formed through a series of surface reactions involving adsorbed boron trichloride, adsorbed methane and gas phase hydrogen. The simultaneous fit of the experimental rate data to the model expressions gave correlation coefficient values of 0.977 and 0.948, in predicting the B4C and BHCl2 formation rates, respectively. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Reversible Cytotoxic Edema in a Cirrhotic Patient Following TIPSJOURNAL OF NEUROIMAGING, Issue 4 2009James R. Babington MD ABSTRACT The authors report the magnetic resonance imaging (MRI) findings in a 52-year-old man with cirrhosis from chronic hepatitis C who developed episodic acute hepatic encephalopathy Type C following placement of transjugular intrahepatic portosystemic shunt (TIPS). Brain MRI revealed hyperintense T2 signal and restricted diffusion distributed through the cerebral cortex. The patient's mentation improved with treatment of his hyperammonemia. Brain MRI performed 5 months later revealed diffuse cerebral atrophy and new areas of hyperintense T2 signal in the cerebral white matter. The cortical signal abnormalities and low apparent diffusion coefficient values on the initial MRI resolved with exception of a mild amount of hyperintense FLAIR signal in the cingulate cortex. Acute hepatic encephalopathy following portosystemic shunting,either from placement of TIPS or from development of spontaneous shunts,is a widely recognized complication of portal hypertension and cirrhosis. We report MRI findings of reversible cytotoxic edema in a patient with acute hepatic encephalopathy following placement of TIPS. [source] Investigation of solute permeation across hydrogels composed of poly(methyl vinyl ether- co -maleic acid) and poly(ethylene glycol)JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2010Thakur Raghu Raj Singh Abstract Objectives, Swelling kinetics and solute permeation (theophylline, vitamin B12 and fluorescein sodium) of hydrogels composed of poly(methyl vinyl ether- co -maleic acid) (PMVE/MA) and poly(ethylene glycol) (PEG) are presented. Methods, The effects of PMVE/MA and PEG 10 000 content on swelling behaviour (percentage swelling, the type of diffusion and swelling rate constant) were investigated in 0.1 m phosphate buffer. Network parameters, such as average molecular weight between crosslinks (Mc) and crosslink density, were evaluated. Key findings, The percentage swelling and Mc of hydrogels increased with decrease in PMVE/MA content, where the water diffusion mechanism into the hydrogels was Class-II type. In contrast, increase in PMVE/MA content caused an increase in the crosslink density. Permeation of theophylline, vitamin B12 and fluorescein sodium, with increasing hydrodynamic radii, was studied through the equilibrium swollen hydrogels composed of PMVE/MA and PEG. In general, the permeability and diffusion coefficients of all three solutes decreased with increase in the PMVE/MA content. In addition, permeability and diffusion coefficient values increased with decreases in the hydrodynamic radii of the solute molecules. Conclusions, The hydrogels have shown a change in swelling behaviour, crosslink density, Mc and solute permeation with change in PMVE/MA content, thus suggesting a potential application in controlled drug-delivery systems. [source] Bi2O3,MoO3 Binary System: An Alternative Ultralow Sintering Temperature Microwave DielectricJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2009Di Zhou Preparation, phase composition, microwave dielectric properties, and chemical compatibility with silver and aluminum electrodes were investigated on a series of single-phase compounds in the Bi2O3,MoO3 binary system. All materials have ultralow sintering temperatures <820°C. Eight different xBi2O3,(1,x)MoO3 compounds between 0.2,x,0.875 were fabricated and the associated microwave dielectric properties were studied. The ,-Bi2Mo2O9 single phase has a positive temperature coefficient of resonant frequency (TCF) about +31 ppm/°C, with a permittivity ,r=38 and Qf=12 500 GHz at 300 K and at a frequency of 6.3 GHz. The ,-Bi2Mo3O12 and ,-Bi2MoO6 compounds both have negative temperature coefficient values of TCF,,215 and ,,114 ppm/°C, with permittivities of ,r=19 and 31, Qf=21 800 and 16 700 GHz at 300 K measured at resonant frequencies of 7.6 and 6.4 GHz, respectively. Through sintering the Bi2O3,2.2MoO3 at 620°C for 2 h, a composite dielectric containing both , and , phase can be obtained with a near-zero temperature coefficient of frequency TCF=,13 ppm/°C and a relative dielectric constant ,r=35, and a large Qf,12 000 GHz is also observed. Owing to the frequent difficulty of thermochemical interactions between low sintering temperature materials and the electrode materials during the cofiring, preliminary investigations are made to determine any major interactions with possible candidate electrode metals, Ag and Al. From the above results, the low sintering temperature, good microwave dielectric properties, chemical compatibility with Al metal electrode, nontoxicity and price advantage of the Bi2O3,MoO3 binary system, all indicate the potential for a new material system with ultralow temperature cofiring for multilayer devices application. [source] WATERSHED WEIGHTING OF EXPORT COEFFICIENTS TO MAP CRITICAL PHOSPHOROUS LOADING AREAS,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2003Theodore A. Endreny ABSTRACT: The Export Coefficient model (ECM) is capable of generating reasonable estimates of annual phosphorous loading simply from a watershed's land cover data and export coefficient values (ECVs). In its current form, the ECM assumes that ECVs are homogeneous within each land cover type, yet basic nutrient runoff and hydrological theory suggests that runoff rates have spatial patterns controlled by loading and filtering along the flow paths from the upslope contributing area and downslope dispersal area. Using a geographic information system (GIS) raster, or pixel, modeling format, these contributing area and dispersal area (CADA) controls were derived from the perspective of each individual watershed pixel to weight the otherwise homogeneous ECVs for phosphorous. Although the CADA-ECM predicts export coefficient spatial variation for a single land use type, the lumped basin load is unaffected by weighting. After CADA weighting, a map of the new ECVs addressed the three fundamental criteria for targeting critical pollutant loading areas: (1) the presence of the pollutant, (2) the likelihood for runoff to carry the pollutant offsite, and (3) the likelihood that buffers will trap nutrients prior to their runoff into the receiving water body. These spatially distributed maps of the most important pollutant management areas were used within New York's West Branch Delaware River watershed to demonstrate how the CADA-ECM could be applied in targeting phosphorous critical loading areas. [source] HYDROLOGIC MODELING AT THE WATERSHED SCALE USING NPSM,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2000Lee Carrubba ABSTRACT: The Nonpoint Source Model (NPSM) was chosen for nonpoint source pollutant modeling within three different watersheds. The first step in using NPSM, hydrologic calibration, is discussed here for three 8-digit Hydrologic Unit Codes (HUCs) from the White River Basin in Indiana (Driftwood HUC), the Albemarle-Pamlico River Basin in Virginia and North Carolina (Contentnea HUC), and the Apalachicola-Chattahoochee-Flint River Basin in Alabama, Georgia, and Florida (Ichawaynochaway HUC). Model predicted flows were compared statistically with USGS gauge data at the HUC outflow points for an uncalibrated and calibrated model run for the period from January 1, 1990, through December 31, 1992, and a validation run for the period from January 1, 1993, through December 31, 1995. Least squares regression of NPSM predicted flows versus USGS gauge data were 0.75, 0.44, and 0.69 for the calibration runs and 0.71, 0.69, and 0.64 for the validation runs in the Driftwood, Contentnea, and Ichawaynochaway HUCs, respectively. Nash Sutcliffe coefficient values were not as strong, ranging from ,0.66 to 0.45 for the calibration runs and 0.31 to 0.37 for the validation runs of the model. The Ichawaynochaway HUC proved the most difficult to calibrate indicating that the model may not be as useful in some geographic locations. [source] Measurement of aroma compound self-diffusion in food models by DOSYMAGNETIC RESONANCE IN CHEMISTRY, Issue 6 2004Thierry Gostan Abstract Self-diffusion measurement of solutes in polymer gels has been investigated using pulsed gradient spin echo NMR spectroscopy. However, few data are available on the self-diffusion of small solutes in natural polysaccharide polymers used as thickeners in the food industry. Since aroma diffusion in food matrices could have an impact on flavor release, this is an interesting and economic challenge. Diffusion ordered spectroscopy (DOSY) resolves diffusion data for each component in complex mixtures. We used DOSY with the inverse Laplace transform approach with the maximum entropy algorithm to investigate diffusion of two aroma compounds, ethyl butanoate and linalool, in an ,-carrageenan matrix as the food model. We showed that the self-diffusion coefficient values of small molecules in a polysaccharide matrix could be easily extracted using this method. We then investigated the impact of the gelling state of ,-carrageenan matrices on the self-diffusion of ethyl butanoate. Copyright © 2004 John Wiley & Sons, Ltd. [source] Assessment in the context of uncertainty: how many members are needed on the panel of reference of a script concordance test?MEDICAL EDUCATION, Issue 3 2005R Gagnon Purpose, The script concordance test (SCT) assesses clinical reasoning in the context of uncertainty. Because there is no single correct answer, scoring is based on a comparison of answers provided by examinees with those provided by members of a panel of reference made up of experienced practitioners. This study aims to determine how many members are needed on the panel to obtain reliable scores to compare against the scores of examinees. Methods, A group of 80 residents were tested on 73 items (Cronbach's ,: 0.76). A total of 38 family doctors made up the pool of experienced practitioners, from which 1000 random panels of reference of increasing sizes (5, 10, 15, 20, 25 and 30) were generated with a resampling procedure. Residents' scores were computed for each panel sample. Units of analysis were means of residents' score, test reliability coefficient and correlation coefficient between scores obtained with a given panel of reference versus the scores obtained with the full panel of 38. Statistics were averaged across the 1000 samples for each panel size for the mean and test reliability computations, and across 100 samples for the correlation computation. Results, For sample variability, there was a 3-fold increase in standard deviation of means between a sample panel size of 5 (SD = 1.57) and a panel size of 30 (SD = 0.50). For reliability, there was a large difference in precision between a panel size of 5 (0.62) and a panel size of 10 (0.70). When the panel size was over 20, the gain became negligible (0.74 for 20 and 0.76 for 38). For correlation, the mean correlation coefficient values were 0.90 with 5 panel members, 0.95 with 10 members and 0.98 with 20 members. Conclusion, Any number over 10 is associated with acceptable reliability and good correlation between the samples versus the full panel of 38. For high stake examinations, using a panel of 20 members is recommended. Recruiting more than 20 panel members shows only a marginal benefit in terms of psychometric properties. [source] Determination of molar mass and solution properties of cationic hydroxyethyl cellulose derivatives by multi-angle laser light scattering with simultaneous refractive index detectionPOLYMER INTERNATIONAL, Issue 10 2009Wei Gao Abstract BACKGROUND: A complete understanding of the molar mass and solution properties of raw materials in bio/pharmaceutical products under bio-application and natural conditions ensures process control, product performance and quality. Biopolymers including polymeric cationic hydroxyethyl cellulose derivatives (e.g. Polyquaterium-10 or Polymer JR) have long been used in health care formulations including shampoos, lotions, eye drops and contact lens multi-purpose solutions. Previously reported molar masses and conformation of Polymer JR were based on size exclusion chromatography-related techniques, which required highly concentrated buffered salt solutions and organic solvent modifiers to prevent undesirable interactions, and did not represent the isotonic conditions in products and applications. RESULTS: This paper describes the characterization of Polymer JR in saline using a new approach that combines micro-batch mode multi-angle laser light scattering with simultaneous refractive index measurements (MB-MALLS-RI). Mass-average molar mass, z -average radius of gyration and second virial coefficient values in phosphate buffer saline (PBS) were obtained and are discussed in detail. CONCLUSION: The molar mass and solution properties of Polymer JR in PBS, with the same pH and ionic strength as most health care solution products, can be characterized using the MB-MALLS-RI technique. The approach is practical and can be widely used for the analysis of other cationic biopolymers. Copyright © 2009 Society of Chemical Industry [source] Development of homochiral peptides in the chemical evolutionary process: Separation of homochiral and heterochiral oligopeptidesCHIRALITY, Issue S1 2003Toratane Munegumi Abstract Living organisms have one-handed structures of L-amino acids in proteins and D-sugars in nucleic acids. Although the origins of each one-handed structure (or homochirality) have been discussed for many years, these discussions have been restricted to monomeric compounds, such as amino acids and monosaccharides, or their stereospecific condensation reactions. Oligomers of these compounds have to be considered in the accumulation processes of homochirality because of the differences in physical properties of the diastereomers. High-performance liquid chromatography (HPLC) and the calculation of the partition coefficient values showed that the peptides having heterochiral sequences like L-Ala-D-Ala or D-Ala-L-Ala were more hydrophobic than the peptides having homochiral ones (L-Ala-L-Ala and D-Ala-D-Ala). Similar results were given from the calculation of most linear dipeptides and all cyclic ones composed of Gly, Ala, Val, or Asp. In addition, longer homo-oligopeptides composed of Ala, Val, or Asp also gave similar results. This general tendency would be useful for the separation of diastereomeric oligopeptides in water. The results also suggest that the separation of the homochiral peptides from the heterochiral ones by their solubility in water could have progressed in a primitive hydrosphere. Chirality 15:S108,S115, 2003. © 2003 Wiley-Liss, Inc. [source] | |||||||||||||||||||