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High Coefficient (high + coefficient)
Selected AbstractsA cohort study to examine whether time and risk preference is related to smoking cessation successADDICTION, Issue 6 2009Rei Goto ABSTRACT Aim To identify whether time and risk preference predicts relapse among smokers trying to quit. Design A cohort study of smokers who had recently started to quit. Time and risk preference parameters were estimated using a discrete choice experiment (DCE). Participants A total of 689 smokers who began quitting smoking within the previous month. Measurements Time discount rate, coefficient of risk-aversion measured at study entry and duration of smoking cessation measured for 6 months. Findings In the unadjusted model, Cox's proportional hazard regression showed that those with a high time discount rate were more likely to relapse [hazard ratio: 1.18, 95% confidence interval (CI): 1.11,1.25]. A high coefficient of risk-aversion reduced the hazard of relapse (0.96, 0.96,0.97). When adjusted for other predictors of relapse (age, gender, self-efficacy of quitting, health status, mood variation, past quitting experience, the use of nicotine replacement therapy, nicotine dependence), the hazard ratios of time discount rate and the coefficient of risk-aversion is 1.17 (95% CI: 1.10,1.24) and 0.98 (95% CI: 0.97,0.99), respectively. Conclusions Those who emphasize future rewards (time,patient preference) and those who give more importance to rewards that are certain (higher risk-aversion) were significantly more likely to continue to abstain from smoking. [source] Evaluation of Various Unstructured Kinetic Models for the Production of Protease by Bacillus sphaericus,MTTC511ENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2008A. Rajendran Abstract Bacillus sphaericus,MTCC511 was used for the production of protease in submerged batch fermentation. Maximum protease activity of 1010,U/L was obtained during a fermentation period of 24,h under optimized conditions of 30,°C in a medium with an initial pH of 7 and at a shaking rate of 120,rpm. The maximum biomass obtained in the batch fermentation was 2.55,g/L after 16,h. Various unstructured models were analyzed to simulate the experimental values of microbial growth, protease activity and substrate concentration. The unstructured models, i.e. the Monod model for microbial growth, the Monod incorporated Luedeking-Piret model for the production of protease and the Monod-incorporated modified Luedeking-Piret model for the utilization of substrate were capable of predicting the fermentation profile with high coefficient of determination (R2) values of 0.9967, 0.9402 and 0.9729, respectively. The results indicated that the unstructured models were able to describe the fermentation kinetics more effectively. [source] Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary reportINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2010F. L. C. D'Assunção D'Assunção FLC, Albuquerque DS, Salazar-Silva JR, Dos Santos VC, Sousa JCN.Ex vivo evaluation of the accuracy and coefficient of repeatability of three electronic apex locators using a simple mounting model: a preliminary report. International Endodontic Journal, 43, 269,274, 2010. Abstract Aim, To compare ex vivo the accuracy and coefficient of repeatability of three electronic apex locators in locating the apical constriction. Methodology, Thirty-one single-rooted teeth were used. The teeth were sectioned at the cement,-enamel junction. A mounting model was used for the measurement of electronic length (EL). The Root ZX-II, the Mini Apex Locator and the Novapex were used for electronic measurements. Each electronic measurement was obtained and repeated. After the last measurement, the file was cemented in place, and the apical 4 mm of each root canal was exposed. The distance from the tip of the file to the apical constriction was determined by three investigators and compared with the corresponding ELs. Results, The coefficient of repeatability of all devices was acceptable: Root ZX-II, 0.04 mm; Mini Apex Locator, 0.10 mm; and Novapex, 0.08 mm. There was little variation in inter-examiner agreement; the ,C (Lin) correlation coefficient was 0.83 for examiners 1 and 2, 0.88 for examiners 1 and 3 and 0.99 for examiners 2 and 3. Using the Root ZX-II, 13 of 31 electronic measurements were located at the apical constriction (42%). Otherwise, the tip of the file was not located at the apical constriction in any of the electronic measurements with the other two devices. The Wilcoxon signed rank test did not reveal any statistical difference between the Root ZX-II measurements and the actual length (P = 0.628), but there was a statistical difference between the Mini Apex Locator and Novapex measurements and the actual length position (P < 0.05). Conclusions, The devices tested in this study had a high coefficient of repeatability. The Root ZX-II was accurate, but the Mini Apex Locator and Novapex were not accurate in locating the apical constriction. [source] Relationship between Postmortem Changes and Browning of Boiled, Dried, and Seasoned Product Made from Japanese Common Squid (Tedarodes pacificus) Mantle MuscleJOURNAL OF FOOD SCIENCE, Issue 1 2007Yuji Omura ABSTRACT:, To clarify the process that possibly causes discoloration in boiled, dried, and seasoned squid products ("sakiika" or "ikakun" in Japanese), we investigated the relationship of squid freshness with the rate of browning using the boiled, freeze-dried, and ground squid product model. ATP and its related compounds in Japanese common squid (Tedarodes pacificus) decomposed gradually during storage, yielding hypoxanthine and ribose at 24 h postmortem. The browning rate of the model during preservation as revealed by the increase of the b* value showed a high coefficient in the linear regression against ribose content (R2= 0.767). Only the model made from the squid stored for 24 h postmortem turned brown. These results strongly suggest that ribose produced during storage plays a major role in the browning of dried and seasoned squid products. [source] UCHL-1 gene in multiple system atrophy: A haplotype tagging approachMOVEMENT DISORDERS, Issue 10 2005Daniel G. Healy MD Abstract To date, the etiology of multiple system atrophy (MSA) has proved impenetrable. We investigated the role of genetic variation in the UCHL-1 gene in MSA and looked for the presence of disease susceptibility alleles. We determined the linkage disequilibrium structure of the gene and employed a haplotype tagging strategy with power to represent 95% of the haplotype diversity. This approach was performed using a set of tagging single nucleotide polymorphisms (SNPs) that can infer the allelic state of all the common SNPs in UCHL-1 with a high coefficient of determination. This strategy enabled us to scan across the gene and maintain the power to detect signal(s) from any potential functional variant(s). In 257 Gilman-probable or -definite MSA subjects and 1,536 controls, we did not detect a case,control frequency difference for either the tagged haplotypes or for individual tagging SNPs. This search included the S18Y variant of UCHL-1, which has been reported to be protective in Parkinson's disease. © 2005 Movement Disorder Society [source] Response surface modeling and optimization for production of ammonia from urea in a batch reactorASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2009J. N. Sahu Abstract Ammonia is applied to removal of NOx contaminates contained in a flue gas stream from energy producing boilers and increase of efficiency of an electrostatic precipitator for removal of fly ash from flue gas stream from a boiler using fossil fuel. In this study, urea hydrolysis for production of ammonia, in different application areas that requires safe use of ammonia, was investigated in a batch reactor. The single and combined effects of operating parameters such as initial feed concentrations, temperature, time and stirring speed on the production of ammonia from urea were analyzed using response surface methodology (RSM). A 24 full factorial central composite experimental design was employed. Analysis of variance (ANOVA) showed a high coefficient of determination value (R2 = 0.976) and satisfactory prediction second-order regression model was derived. The optimum production conditions were determined as temperature, 180 °C; initial feed concentrations, 22.24 wt% of urea; time, 74.9 min and stirring speed, 1150 rpm. At optimum conversion conditions, the conversion of urea for production of ammonia was found to be 75.65%. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Reliable and reproducible anterior active rhinomanometry for the assessment of unilateral nasal resistanceCLINICAL OTOLARYNGOLOGY, Issue 6 2000A.S. Carney Unilateral nasal resistance is now thought to be more important than total resistance in promoting obstructive symptoms. We assessed the reproducibility of anterior active rhinomanometry in measuring unilateral nasal resistance. Ten baseline readings of unilateral nasal resistance were made over a 30-min period in seven healthy subjects (14 nostrils) using anterior active rhinomanometry performed according to the International Committee for the Standardization of Rhinomanometry (ICSR) guidelines. Baseline readings revealed that measurements using anterior active rhinomanometry had an unacceptably high coefficient of variation (19%,60%). With a more time-consuming revised protocol involving multiple recordings and the identification and exclusion of erroneous data, coefficients of variation of 7%,15% were obtained. We conclude that single anterior active rhinomanometry readings are potentially prone to large errors and each researcher using such equipment must satisfy his/herself that their methodology has an acceptable coefficient of variation in their hands. The ICSR guidelines are not always sufficient to allow reproducible measurement and specially designed protocols may be necessary to produce reliable results. [source] ACIDIC ELECTROLYZED WATER PROPERTIES AS AFFECTED BY PROCESSING PARAMETERS AND THEIR RESPONSE SURFACE MODELSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 1 2004GABRIEL O. I. EZEIKE Several studies of acidic electrolyzed (EO) water demonstrated the efficacy of EO water for inactivation of different foodborne pathogens and reported on the chemical species present in EO water. This study was conducted to investigate the effect of production parameters (voltage, NaCl concentration, flow rate, and temperature) on the properties of EO water and to model the complex reactions occurring during the generation of EO water. At 0.1% salt concentration, EO water was produced at 2, 10, and 28 V. However, due to high conductivity of the electrolyte at 0.5% salt concentration, the voltage applied across the cell was limited to 7 V. The electrolyte flow rate was set at 0.5, 2.5, and 4.5 L/mn. For pH and oxidation-reduction potential (ORP), NaCl concentration was the most significant factor followed by voltage, electrolyte flow rate and temperature, respectively. However, in the case of residual chlorine, flow rate was relatively more important than voltage. Response surface methodology yielded models to predict EO water properties as functions of the process parameters studied, with very high coefficients of determination (R2= 0.872 to 0.938). In general, the higher the NaCl concentration and voltage, the higher the ORP and residual chlorine of EO water. Increased electrolyte flow rate will produce EO water with lower ORP and residual chlorine due to the shorter residence time in the electrolytic cell. [source] Relationship of inbreeding with sperm quality and reproductive success in Mexican gray wolvesANIMAL CONSERVATION, Issue 3 2007C. Asa Abstract The ultimate goal of the Mexican gray wolf Canis lupus baileyi captive management program is reintroduction of healthy individuals into wild habitats. To this end, zoo population managers work to provide not only for the physical well-being but also for the genetic health of these animals. However, the very limited genetic founder base, exacerbated by breeding within three distinct lineages, resulted in very high coefficients of inbreeding. Because support for measurable levels of inbreeding depression in the captive wolf population, as defined by reductions in common fitness measures such as juvenile survival or reproductive success, has been weak, we investigated the potential effects on male reproductive capacity. We analyzed semen samples from wolves from all three lineages and compared them with samples from subsequent lineage crosses and from generic gray wolves. We not only found a significant effect of inbreeding on sperm quality but we related both inbreeding and sperm quality to reproductive success. Samples from male offspring of lineage crosses, with inbreeding coefficients of zero were similar in quality to those from generic gray wolves. However, samples from a limited number of offspring from back-crosses were of extremely poor quality. Although it is reassuring that sperm quality was so much improved in male offspring of lineage crosses, the concomitant reduction in inbreeding coefficient does not eliminate the potentially deleterious alleles. Our results demonstrate that sperm quality is an important indicator of fertility and reproductive success in Mexican wolves. In addition, our data lend further support to the presence of inbreeding depression in this taxon. [source] Scaling the structure,function relationship for clinical perimetryACTA OPHTHALMOLOGICA, Issue 4 2005Ronald S. Harwerth Abstract. Purpose:,The full ranges of glaucomatous visual field defects and retinal ganglion cell losses extend over several orders of magnitude and therefore an interpretation of the structure,function relationship for clinical perimetry requires scaling of both variables. However, the most appropriate scale has not been determined. The present study was undertaken to compare linear and logarithmic transformations, which have been proposed for correlating the perimetric defects and neural losses of glaucoma. Methods:,Perimetry, by behavioural testing, and retinal histology data were obtained from rhesus monkeys with significant visual field defects caused by experimental glaucoma. Ganglion cell densities were measured in histologic sections of retina that corresponded to specific perimetry test locations for the treated and control eyes. The linear (percentage) and logarithmic (decibel) relationships for sensitivity loss as a function of ganglion cell loss were analysed. Results:,With decibel scaling, visual sensitivity losses and ganglion cell densities were linearly correlated with high coefficients of determination (r2), although the parameters of the functions varied with eccentricity. The structure,function relationships expressed as linear percentage-loss functions were less systematic in two respects. Firstly, the relationship exhibited considerable scatter in the data for small losses in visual sensitivity and, secondly, visual sensitivity losses became saturated with larger losses in ganglion cell density. The parameters of the percentage-loss functions also varied with eccentricity, but the variation was less than for the decibel-loss functions. Conclusions:,Linear scaling of perimetric defects and ganglion cell losses might potentially improve the structure,function relationship for visual defects associated with small amounts of cell loss, but the usefulness of the relationship is limited because of the high variability in that range. With log,log co-ordinates, the structure,function relationship for clinical perimetry is relatively more accurate and precise for cell losses greater than about 3 dB. The comparatively greater accuracy and precision of decibel loss functions are a likely consequence of the logarithmic scale of stimulus intensities for perimetry measurements and because the relationship between visual sensitivity and the number of neural detectors is a form of probability summation. [source] | ||||||||||||||||