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Predictive Correlation (predictive + correlation)
Selected AbstractsNew Predictive Correlations for the Drop Size in a Rotating Disc Contactor Liquid-Liquid Extraction ColumnCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 2 2007M. Ismail Al-Rahawi Abstract Sauter mean drop sizes (d32) generated from a hole distributor in liquid extraction RDC columns were studied under various conditions. Experiments were designed to generate data required to determine the main variables that control the drop sizes in RDCs. Two precise correlations were proposed for predicting d32 in a RDC extraction column. The first was based on operating variables, hole-distributor diameter, disc speed, column geometry, and system physical properties. The second one considered the same variables, except the column geometry. This model can be used for design purposes. The two correlations are the first of their type to consider the distributor hole inlet diameter in a RDC column. This diameter has been neglected by previous investigators. The maximum standard deviation for all data is 0.75,%, with a maximum absolute error of 6.8,%. [source] Effect of anesthetic structure on inhalation anesthesia: Implications for the mechanismJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 6 2008Michael H. Abraham Abstract Many previous attempts (e.g., the Meyer,Overton hypothesis) to provide a single set of physical or chemical characteristics that accurately predict anesthetic potency have failed. A finding of a general predictive correlation would support the notion of a unitary theory of narcosis. Using the Abraham solvation parameter model, the minimum alveolar concentration, MAC, of 148 varied anesthetic agents can be fitted to a linear equation in log (1/MAC) with R2,=,0.985 and a standard deviation, SD,=,0.192 log units. Division of the 148 compounds into a training set and a test set shows that log (1/MAC) values can be predicted with no bias and with SD,=,0.20 log units. The two main factors that determine MAC values are compound size and compound hydrogen bond acidity, both of which increase anesthetic activity. Shape has little or no effect on anesthetic activity. Our observations support a unitary theory of narcosis by inhalation anesthetics. A two-stage mechanism for inhalation anesthesia accounts for the observed structural effects of anesthetics. In this mechanism, the first main step is transfer of the anesthetic to the site of action, and the second step is interaction of the anesthetic with a receptor(s). © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:2373,2384, 2008 [source] Flow of Newtonian and power law liquids in tube bundlesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009U. K. Singh Abstract In this work, the annular (tangential) flow of Newtonian and non-Newtonian fluids in tube bundles has been studied experimentally. Extensive pressure drop data has been obtained embracing wide ranges of the Reynolds number (13,6600) and for two test modules of different geometrical arrangements, but of similar overall void fraction. Preliminary experiments suggest that the pressure drop is mainly determined by the overall void fraction of the bundle and is relatively insensitive to the detailed geometrical configuration of the bundle. A simple predictive correlation has been developed which reconciles the present results for Newtonian and power law fluids with acceptable levels of reliability. Dans le cadre de ces travaux, on a examiné de façon expérimentale l'écoulement annulaire (tangentiel) des fluides newtoniens et non newtoniens dans des faisceaux tubulaires. On a obtenu de nombreuses données de chute de pression englobant de vastes plages du nombre de Reynolds (13-6600), et pour deux modules d'essai de différentes dispositions géométriques, mais à taux de vide global similaire. Les expériences préliminaires suggèrent que la chute de pression est déterminée principalement par le taux de vide global du faisceau et est relativement insensible à la configuration géométrique détaillée du faisceau. La création d'une simple corrélation prédictive a permis de rapprocher les présents résultats pour les fluides newtoniens et des fluides en loi de puissance avec des niveaux acceptables de fiabilité. [source] Mutant p53 and cyclin A1 protein expression in primary laryngeal squamous cell carcinomas do not correlate to second primary tumours of the head and neck,ANZ JOURNAL OF SURGERY, Issue 1-2 2009Ross D. Farhadieh Abstract Background:, Field cancerization is a feature of head and neck squamous cell carcinoma. No biological marker in the index tumour has been correlated to the development of second primary tumours (SPT). Cyclin A1 is a cell cycle regulator and a downstream target of p53. This study assessed predictive correlation of cyclin A1 and mut-p53 with clinicopathological parameters and occurrence of (SPT) 7in the head and neck. Methods:, Using immunohistochemistry 106 patients treated for primary laryngeal squamous cell carcinoma were investigated for expression of cyclin A1 and mut-p53. Results:, Expression of cyclin A1 and mut-p53 were noted in 83 of 106 (78.3%) and 25 of 106 (23.6%) patients. There was a weak but significant correlation between mut-p53 and cyclin A1 (r = 0.301, P = 0.002) expression. During the follow-up period (median 41.0 months (range 1,205 months)), 21 of 106 (19.8%) patients developed an SPT. There was no statistically significant correlation between the markers investigated and disease recurrence, SPT diagnosis or clinicopathological parameters. Conclusion:, Second primary tumours are an intriguing problem in treatment of HNSCC and a predictive marker identifying those greatest at risk would be a leap forward. [source] Early development of children at familial risk for Dyslexia,follow-up from birth to school ageDYSLEXIA, Issue 3 2004H. Lyytinen Abstract We review the main findings of the Jyväskylä of Dyslexia (JLD) which follows the development of children at familial risk for dyslexia (N = 107) and their controls (N = 93). We will illustrate the development of these two groups of children at ages from birth to school entry in the skill domains that have been connected to reading and reading disability in the prior literature. At school entry, the highest score on the decoding task among the poorer half (median) of the at risk children,i.e. of those presumably being most likely genetically affected,is 1 SD below the mean of the control group. Thus, the familial risk for dyslexia shows expected consequences. Among the earliest measures in which group differences as well as significant predictive associations with the first steps in reading have emerged, are indices of speech processing in infancy. Likewise, various measures of early language including pronunciation accuracy, phonological, and morphological skills (but not performance IQ) show both group differences and predictive correlations, the majority of which become stronger as the reliability of the measures increases by age. Predictive relationships tend to be strong in general but higher in the at risk group because of its larger variance in both the predictor variables and in the dependent measures, such as early acquisition of reading. The results are thus promising in increasing our understanding needed for early identification and prevention of dyslexia. Copyright © 2004 John Wiley & Sons, Ltd. [source] Concurrent and predictive validity of the Phelps Kindergarten Readiness Scale-IIPSYCHOLOGY IN THE SCHOOLS, Issue 4 2005Jennifer Duncan The purpose of this research was to establish the concurrent and predictive validity of the Phelps Kindergarten Readiness Scale, Second Edition (PKRS-II; L. Phelps, 2003). Seventy-four kindergarten students of diverse ethnic backgrounds enrolled in a northeastern suburban school participated in the study. The concurrent administration of the PKRS-II and the Woodcock-Johnson III Brief Intellectual Ability Scale (R.W. Woodcock, K.S. McGrew, & N. Mather, 2001a) occurred in the fall of the kindergarten year. To assess predictive validity, the Woodcock Johnson III Tests of Achievement (R.W. Woodcock, K.S. McGrew, & N. Mather, 2001b) was administered in the spring of that year. All concurrent and predictive correlations were significant. Based on the results of this study, the PKRS-II may be used with confidence to screen for children who may be at risk for academic difficulties. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 355,359, 2005. [source] Influence of nonspecific brain and plasma binding on CNS exposure: implications for rational drug discoveryBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 8 2002J. Cory Kalvass Abstract Relative plasma, brain and cerebrospinal fluid (CSF) exposures and unbound fractions in plasma and brain were examined for 18 proprietary compounds in rats. The relationship between in vivo brain-to-plasma ratio and in vitro plasma-to-brain unbound fraction (fu) was examined. In addition, plasma fu and brain fu were examined for their relationship to in vivo CSF-to-plasma and CSF-to-brain ratios, respectively. Findings were delineated based on the presence or absence of active efflux. Finally, the same comparisons were examined in FVB vs. MDR 1a/1b knockout mice for a selected P-glycoprotein (Pgp) substrate. For the nine compounds without indications of active efflux, predictive correlations were observed between ratios of brain-to-plasma exposure and plasma-to-brain fu (r2 = 0.98), CSF-to-brain exposure vs. brain fu (r2 = 0.72), and CSF-to-plasma exposure vs. plasma fu (r2 = 0.82). For the nine compounds with indications of active efflux, nonspecific binding data tended to over predict the brain-to-plasma and CSF-to-plasma exposure ratios. Interestingly, CSF-to-brain exposure ratio was consistently under predicted by brain fu for this set. Using a select Pgp substrate, it was demonstrated that the brain-to-plasma exposure ratio was identical to that predicted by plasma-to-brain fu ratio in MDR 1a/1b knockout mice. In FVB mice, plasma-to-brain fu over predicted brain-to-plasma exposure ratio to the same degree as the difference in brain-to-plasma exposure ratio between MDR 1a/1b and FVB mice. Consistent results were obtained in rats, suggesting a similar kinetic behavior between species. These data illustrate how an understanding of relative tissue binding (plasma, brain) can allow for a quantitative examination of active processes that determine CNS exposure. The general applicability of this approach offers advantages over species- and mechanism-specific approaches. Copyright © 2002 John Wiley & Sons, Ltd. [source] | |||||||||||||