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Very Good Correlation (very + good_correlation)
Selected AbstractsSeismic evaluation of 1940s asymmetric wood-frame building using conventional measurements and high-definition laser scanningEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 10 2009Khalid M. Mosalam Abstract This study presents results from shake table experiments of a wood-frame building conducted at the University of California, Berkeley. A 13.5-ft × 19.5-ft two-story wood-frame building representing San Francisco 1940s design of a residential building with a garage space on the first story (house-over-garage) was tested. The test building was subjected to scaled ground motion based on Los Gatos record from Loma Prieta 1989 earthquake. The strong motion time history was scaled to match design spectra of a site in Richmond district of San Francisco. The test results demonstrated the seismic vulnerability of the test building due to soft story mechanism and significant twisting when shaken in two horizontal directions. In addition to conventional instrumentation for measuring acceleration and position of selected points of the test building, high-definition laser scanning technology was employed to assess global and local anomalies of the building after the shake table tests. The analysis conducted in this study showed very good correlation between conventional data recorded from position transducers and the laser scans. These laser scans expanded limits of conventional data at discrete points and allowed analyzing the whole building after shaking. Copyright © 2009 John Wiley & Sons, Ltd. [source] Discrepancy between Gradients Derived by Cardiac Catheterization and by Doppler Echocardiography in Aortic Stenosis: How Often Does Pressure Recovery Play a Role?ECHOCARDIOGRAPHY, Issue 9 2009Studies have shown very good correlation between Doppler-derived gradients and gradients obtained by cardiac catheterization (cath) in aortic stenosis (AS). However, the phenomenon of pressure recovery may lead to significant overestimation of aortic valve (AV) gradients by Doppler echocardiography (echo). We hypothesized that echo-derived gradients will be higher in mild,moderate AS because of pressure recovery. We studied 94 patients who had echo and cardiac caths in a span of 1 week. The mean age was 72 ± 13 years, 54% males, 79% had coronary artery disease, and the mean left ventricular ejection fraction was 45 ± 22%. The mean cardiac output and cardiac indices were 5.1 ± 1.4/2.7 ± 0.6 (l/mt), (l/m2), respectively. For those with mild AS, echo overestimated gradients in 9.5% of patients (4/42) by an average of 19 mmHg, thus misclassifying the degree of stenosis. In those with moderate AS, 14% (3/21) were misclassified as severe AS (gradient overestimation by an average of 13.6 mmHg). In those with severe AS, echo underestimated gradients in 13% (4/31) by an average of 22.7 mmHg. The aorta at the sinotubular junction was 2.8 cm in those patients with mild AS in whom gradients were overestimated by more than 20 mmHg compared to a sinotubular junction diameter of 3.12 cm in those with mild AS and no overestimation of gradients. The AV area/aortic root ratio was 0 .4 in those with mild AS and 0.2 in those with severe AS (P < 0.05). [source] Voltammetric Study of Nitro Radical Anion Generated from Some Nitrofuran Compounds of Pharmacological SignificanceELECTROANALYSIS, Issue 1 2003S. Bollo Abstract The electrochemical behavior of 2-(5-amino- 1,3,4-oxadiazolyl)-5-nitrofuran (NF359) and its comparison with well-known drugs such as nifurtimox (NFX) and nitrofurazone (NFZ) in protic, mixed and aprotic media by cyclic voltammetry, tast and differential pulse polarography was studied. All the compounds were electrochemically reducible in all media being the reduction of the nitrofuran group the main voltammetric signal. The one-electron reduction couple due to the nitro radical anion formation was visualized in mixed (for NF359 and NFZ) and aprotic media (for all compounds). By applying a cyclic voltammetric methodology we have calculated the decay constants (k2) of the corresponding nitro radical anions in mixed and aprotic media. In mixed medium data fit well with a disproportionation reaction of the nitro radical anion but in aprotic medium fit better with a dimerization reaction. Also, considering cyclic voltammetric measurements in aprotic media we have estimated the reduction potential of the RNO2/RNO2., couple in aqueous medium, pH 7 (E17 values) finding very good correlation with E17 values obtained by pulse radiolysis. Furthermore we have calculated the equilibrium constants from the electron transfer from nitro radical anion to oxygen (kO2) finding that nitro radical anion from NF359 is thermodynamically favored to react with oxygen in respect to both NFZ and NFX. [source] Conformationally Biased Selective Alkylation of trans -Cyclohexane-1,2-bis(sulfonamide) Assisted by Solvent-Tuned Protecting Groups: Applications to the Synthesis of a Large Optically Active Polyazamacrocycle,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2006Carmen Peña Abstract The selective alkylation of (R,R)-cyclohexane-1,2-bis(sulfonamide) with trityl bromoalkyl ethers has been studied in detail. The major formation of either mono- or dialkylated compounds clearly depends on the right combination of protecting groups and the reaction solvent. An exhaustive study suggests that this effect can be reasonably explained by the conformational preferences of the monoalkylated compounds, which also depend on the reaction medium, solvophobic effects and weak intramolecular interactions. Structural analysis by NOE measurements showed the presence of folded conformations in solution for all the tested examples. Monte Carlo conformational searches supported this proposal, showing a very good correlation between the fraction of folded species and the selectivity towards monoalkylation. Finally, tuning of the reaction conditions, leading to either extended or folded conformations of the monoalkylated synthetic intermediates, was exploited for the efficient synthesis of a large optically active polyazamacrocycle. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] The effect of interference-fit fasteners on the fatigue life of central hole specimensFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 7 2005A. LANCIOTTI ABSTRACT Fatigue tests were carried out on 2024-T351, thickness 1.6 mm, central hole specimens containing pins installed with five different interference-fit levels. Tests clearly demonstrated the beneficial effect of interference fit on fatigue resistance, up to the maximum value examined, 2.5%. A three-dimensional (3D) finite-element model was used in order to characterize the stress field around the hole. A large specimen, with a 40-mm-diameter hole filled with interference-fit pin, was instrumented by strain gauges and statically tested in order to check FEM results. A very good correlation existed between measured and numerically evaluated strains. FEM results demonstrated the well-known effect of interference-fit fasteners on reducing stress ranges. By increasing the interference level, the stress range was practically unchanged, while the mean stress decreased. Interference-fit produces a biaxial stress state, which must be taken into account for fatigue evaluation. In the present case, a simple criterion, based on hoop strain, predicted the fatigue results quite well with the exception of open hole fatigue test results, which were overestimated. [source] Accuracy and definitive interpretation of preoperative technetium 99m sestamibi imaging based on the discipline of the reader,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2009Ayesha N. Khalid MD Abstract Background. Technetium 99m sestamibi scans have become a principal means of localizing parathyroid adenomas. Its accuracy and reliability has allowed for the proliferation of minimal access parathyroidectomy. Localizing interpretation of these scans often drives referral of hyperparathyroid patients for surgery. Interpretation of these scans may differ between nuclear medicine physicians and surgeons. Methods. We reviewed patients (N = 65) with digital images from an academic medical center with the diagnosis of primary hyperparathyroidism. We assessed the willingness to define an adenoma's location, the interrater reliability, and the accuracy of technetium (Tc-99m) sestamibi read by a surgeon and a nuclear medicine physician. Results. There was poor correlation between both readers for assessment of quality of images (k = 0.54, 0.07) but very good correlation for adenoma location (k = 0.81). Conclusion. Both readers had good accuracy in predicting the location of the parathyroid adenoma. The surgeon was more likely to call a scan positive. © 2008 Wiley Periodicals, Inc. Head Neck, 2009 [source] A validity and reliability study of assessment and screening for sustained withdrawal reaction in infancy: The Alarm Distress Baby scale,INFANT MENTAL HEALTH JOURNAL, Issue 5 2001Antoine Guedeney Sustained withdrawal behavior in infancy is an important alarm signal to draw attention to both organic and relationship disorders. A withdrawal scale, the Alarm Distress Baby scale (ADBB), for infants between 2 and 24 months of age was built. This article describes the construction of the scale and the assessment of its psychometric properties. The ADBB has good content validity, based on the advice of seven experts. The scale has good criterion validity: first, as a measure of the infant's withdrawal reaction, with a very good correlation between nurse and pediatrician on the ADBB (rs = 0.84), and second, as a screening procedure for detecting the developmental risk of the infant. The cutoff score of 5 with a sensitivity of 0.82 and a specificity of 0.78 was determined to be optimal for screening purposes. The scale has good construct validity, with good convergent validity with both the Spitz (1951) and the Herzog & Rathbun (1982) lists of symptoms of infant depression (rs = 0.61 and 0.60, respectively). Exploratory factor analysis showed two different factors, consistent with the scale's construct. Reliability was satisfactory with good internal consistency for both subscales (the Cronbach , = 0.80 for the first subscale and 0.79 for the second) and for the global scale (, = 0.83). The test-retest procedure showed good stability over time (rs = 0.90 and 0.84 for the two different raters). The scale could be used in different clinical settings, provided a sufficient level of social stimulation is given to the infant in a relatively brief period of time. The scale can be used by nurses and psychologists or by medical doctors after a short period of training. © 2001 Michigan Association for Infant Mental Health. [source] Performance evaluation of the PENTRA 60C+ automated hematology analyzer and comparison with the ADVIA 2120INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 2 2009K. GUERTI Summary The PENTRA 60C+ hematology analyzer provides a complete blood cell (CBC) count, including a five-part differential (5-DIFF) count and two leukocyte subpopulations, i.e. large immature cells (LIC's) and atypical lymphocytes (ALY's). We evaluated its analytical performance and assessed agreement with the ADVIA 2120, in order to install the analyzer in a small satellite hematology laboratory. First we assessed repeatability, reproducibility and carry-over to evaluate the analytical performance. Then we used Pearson correlation coefficients, Passing and Bablok regression analysis and a graphical approach (n = 209) to evaluate agreement with the ADVIA 2120. Repeatability and reproducibility were excellent for the majority of CBC and 5-DIFF count parameters. Carry-over was negligible. Our data showed very good correlation for most CBC count parameters. Lower correlation coefficients were observed for red cell distribution width, mean corpuscular volume and mean platelet volume. As compared to the ADVIA 2120, the 5-DIFF count performed very well. Agreement was poorer for low-level eosinophils and basophils. Furthermore, the PENTRA 60C+ was equally able to identify pathological blood samples through the determination of LIC's and ALY's. Therefore, the PENTRA 60C+ is an eligible blood cell counter to be operational in a satellite laboratory setting. [source] Simple method to determine flow characteristics of injectable hydrogelsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2010Sundar Babu Nadarajan Abstract This article presents a simple inexpensive method to measure flow and viscoelastic properties of calcium alginate hydrogels or gel solutions and is particularly suitable for quality control in small laboratory settings. This method can be considered an extension of the Melt Flow Index (MFI) method, which is routinely used in the polymer industry to indirectly determine the molecular weight of polymers. Results of alginate gels at various crosslinking densities obtained with this new test are compared to complex viscosity data obtained from a standard cone and plate rheometer, and demonstrate very good correlation. A mathematical model describing the apparent viscosity of the alginate gels in this test has also been developed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Cell proliferation and differentiation during fracture healing are influenced by locally applied IGF-I and TGF-,1: Comparison of two proliferation markers, PCNA and BrdUJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2003B. Wildemann Abstract Growth factors IGF-I and TGF-,1 are known to stimulate fracture healing. The purpose of this study was to investigate the role of locally applied IGF-I and TGF-,1 during the early phase of fracture healing (Days 5, 10, and 15 after fracture) on cellular processes like proliferation and differentiation in a rat model. Two different immunohistochemical markers were used to analyze cell proliferation: (1) injection of the thymidine analogue BrdU and subsequent immunohistochemical staining for BrdU-positive nuclei, and (2) the antibody against the "proliferating cell nuclear antigen" (PCNA). In comparison, both methods revealed similar results concerning the types of proliferating cells at the different time points and the two groups. Labeling indices of both methods showed very good correlation (e.g., rs: 0.887 and p < 0.001 at day 10 in the control group without growth factors). Comparison of the callus morphology and the proliferation rate showed differences during fracture healing due to the local application of IGF-I and TGF-,1 from coated implants. At Day 5 the callus of the group treated with growth factors displayed an earlier appearance of cartilage compared to the control group. This was accompanied by an onset of cell proliferation in chondrocytes. Likewise, at the later time points an enhanced maturation of the callus tissue and the proliferation pattern were detectable in the growth-factor group. These results indicate that local application of IGF-I and TGF-,1 accelerates early cellular processes during fracture healing. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 65B: 150,156, 2003 [source] Accurate prediction of basicity in aqueous solution with COSMO-RSJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 1 2006Frank Eckert Abstract The COSMO-RS method, a combination of the quantum chemical dielectric continuum solvation model COSMO with a statistical thermodynamics treatment for realistic solvation simulations, has been used for the prediction of base pKa constants. For a variety of 43 organic bases the directly calculated values of the free energies of dissociation in water showed a very good correlation with experimental base pKa values (r2 = 0.98), corresponding to a standard deviation of 0.56 pKa units. Thus, we have an a priori prediction method for base pKa with the regression constant and the slope as only adjusted parameters. In accord with recent findings for pKa acidity predictions, the slope of pKa vs. ,Gdiss was significantly smaller than the theoretically expected value of 1/RTln(10). The predictivity of the presented method is general and not restricted to certain compound classes, but systematic corrections of 1 and 2 pKa units for secondary and tertiary aliphatic amines are required, respectively. The pKa prediction method was validated on a set of 58 complex multifunctional drug-like compounds, yielding an RMS accuracy of 0.66 pKa units. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 11,19, 2006 [source] Stability of Crude Herring Oil Produced from Fresh Byproducts: Influence of Temperature during StorageJOURNAL OF FOOD SCIENCE, Issue 9 2002I. Aidos ABSTRACT: Crude herring oil, extracted from fresh byproducts, was stored at 0, 20, and 50°C in order to study the effect of temperature on lipid oxidation. The oil had an initial peroxide value (PV), anisidine value (AV), and free fatty acids of 0.7 meq peroxides/kg of lipid, 0.4, and 0.6%, respectively. During storage, the oil reached the secondary oxidation stage for all 3 temperatures. The formation of fluorescent compounds was inhibited at 0°C. Significant decrease of the ,-tocopherol content was found after storage at 0 and 20°C, but no consumption occurred at 50°C. The development of oxidation products over time exhibited a temperature-dependency with a very good correlation. [source] Development of Biogenic Amines in Yellowfin Tuna (Thunnus albacares): Effect of Storage and Correlation with Decarboxylase-Positive Bacterial FloraJOURNAL OF FOOD SCIENCE, Issue 1 2002W.-X. Du ABSTRACT: The effects of storage at 0,4,10, and 22°C for 0,1,3,5, and 9 d on the quality of yellowfin tuna fillets as determined by microbiological assessment, development of some biogenic amines, and sensory analysis were studied. Tuna fillets stored at 22 °C for 3 d, 10 °C for 5 d, and 4 °C for 9 d were rated unacceptable for consumption. Those stored at 22 °C for 3 d had total aerobic bacterial count of > 8 log10 CFU/g, a histamine-producing bacterial population of 7 log10 CFU/g, and 832 ppm of histamine, 35.8 ppm of putrescine, and 147 ppm of cadaverine. A comparison of the capillary electrophoresis, AOAC fluorometric method, and gas chromatography showed a very good correlation (r2 > 0.99) among these 3 methods for histamine quantitation in tuna samples. Morganella morganii, Enterobacter agglomerans, Enterobacter intermedium, Pseudomonas fluorescens, Proteins vulgaris, and Serratia liquefaciens were the decarboxylase-positive bacterial species isolated by using the Niven's medium and identified during storage, which were responsible for histamine production in test tuna fillets. [source] A new focus on the Walther equation for lubricant viscosity determinationLUBRICATION SCIENCE, Issue 2 2006M. Sánchez-Rubio Abstract Lubricants are widely used in industrial machinery in order to separate solid tribological surfaces and support high loads under severe conditions. In tribological contacts, viscosity plays an important role in the film-forming abilities of the lubricant, but this property is strongly dependent on temperature. Consequently, small variations in temperature cause appreciable variations in the viscosity of lubricating oils. For this reason it is of practical value to be able to predict viscosity changes with temperature. This paper presents a new focus on the Walther equation to determine the viscosity of commercial lubricants at different temperatures. This new approach provides very good correlation with experimental measurements. Copyright © 2006 John Wiley & Sons, Ltd. [source] Use of the Visual Analog Scale to Rate and Monitor Severity of Nausea in the Emergency DepartmentACADEMIC EMERGENCY MEDICINE, Issue 12 2009FACEM, M Clin Epi, Robert Meek MBBS Abstract Objectives:, The objective was to describe the association between verbal descriptors of nausea severity and visual analog scale (VAS) ratings in an undifferentiated emergency department (ED) population and to calculate the minimum clinically significant difference (MCSD) in VAS rating of nausea severity in this population. Methods:, A prospective observational study was conducted at three EDs on a convenience sample of stable, consenting adult patients presenting with nausea as part of their symptom complex. Data included demographics, adjectival description of nausea severity (none, mild, moderate, or severe), and VAS rating (standard 100-mm line) at enrollment, 30 minutes, and 60 minutes. At 30 and 60 minutes they were also asked to describe any change in nausea severity from the previous rating ("a lot less,""a little less,""the same,""a little more,""a lot more"). The MCSD was defined as the average VAS change when a patient reported "a little less" or "a little more" nausea. Results:, A total of 247 patients provided 693 matched adjectival ratings and VAS scores. Median age was 45 years, and 100 (40%) were male. The median VAS measures for none, mild, moderate, and severe nausea were 2, 23, 53, and 83 mm, respectively. VAS distributions in the verbal categories were statistically different from each other (Spearman rank correlation coefficient = 0.90; p < 0.0001). The MCSD was 22 mm (95% CI = 20 to 24 mm). Conclusions:, There is very good correlation between verbal descriptors of nausea and VAS ratings. The MCSD for VAS nausea ratings in an ED population is 22 mm. [source] Climatic factors influencing the isotope composition of Italian olive oils and geographic characterisationRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 3 2009Paola Iacumin The purpose of this study was to investigate the possibility of identifying oil source areas by means of simple measurements on the natural samples avoiding time-consuming sample treatments. The oxygen and carbon isotopic values of 150 samples of extra-virgin olive oil from eight different Italian regions and from three different years of production were measured according to well-established techniques. Statistical treatments of the results obtained show a very good correlation of the ,18O of oil with latitude, mean annual temperature, and mean relative humidity at the collection site. No correlation is found with elevation and mean annual precipitation. The shift of the oil ,18O per degree centigrade of the mean annual temperature is quantitatively close to that calculated for atmospheric precipitation in continental areas. Accordingly, in our measurements, the year of oil production can be identified on the basis of the ,18O value (mean 2004 temperatures were higher than 2005 temperatures). On the contrary, the oil ,13C values show no correlation with the above variables but only with latitude and, consequently, are less suitable for discriminating the geographic origin of oil. However, the ,13C values are suitable to indicate biological differentiation while the ,18O values are not. Copyright © 2009 John Wiley & Sons, Ltd. [source] Pharmacological and pharmacokinetic evaluation of celecoxib prodrugs in ratsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 7 2002Rao N.V.S. Mamidi Abstract This study demonstrates the utility of an in vitro , in vivo correlative approach in the selection and optimization of a prodrug candidate of celecoxib (CBX), a COX2 inhibitor. As an initial screening step, a comparative single oral dose pharmacokinetic study was conducted in rats for CBX and its three aliphatic acyl water-soluble prodrugs viz., CBX-acetyl (CBX-AC), CBX-propionyl (CBX-PR) and CBX-butyryl (CBX-BU) at high equimolar dose, 100 mg/kg. Only CBX-BU and CBX-PR converted rapidly to CBX and yielded approximately five-fold greater systemic exposure of CBX than CBX alone or CBX-AC. Rank order of systemic exposure of prodrugs in its intact form was CBX-AC >CBX-PR >CBX-BU. Further in vitro hydrolysis studies of CBX prodrugs in intestinal mucosal suspensions and liver homogenates indicated that CBX-BU is rapidly and completely converted to CBX, whereas CBX-PR and CBX-AC require longer incubation period for complete conversion to CBX. There was a very good correlation of the in vitro and in vivo data supporting CBX-BU as the prodrug of choice. Further in vitro pharmacological studies showed that COX2 selective inhibition is improved for CBX-BU as compared to CBX-AC and CBX-PR. Dose proportionality in pharmacokinetic studies of CBX-BU and CBX at equimolar oral doses confirmed that relative oral bioavailability of CBX was improved following CBX-BU administration and there was linearity in pharmacokinetics of CBX over a wide dose range (10,100 mg/kg), whereas CBX in its conventional form showed poor bioavailability and lack of dose linearity in pharmacokinetics. The oral bioavailability of CBX from CBX-BU was dose independent and was in the range 78,96%. At a 50% reduced molar dose, CBX-BU showed an equivalent efficacy to that of CBX in the in vivo carrageenan model. Based on the study, water-soluble CBX-BU prodrug can be considered for clinical development in view of its potential advantages.Copyright © 2002 John Wiley & Sons, Ltd. [source] Wireless contact lens sensor for intraocular pressure monitoring: assessment on enucleated pig eyesACTA OPHTHALMOLOGICA, Issue 4 2009Matteo Leonardi Abstract. Purpose:, Assessment on enucleated pig eyes of a novel and minimally invasive method for the continuous monitoring of intraocular pressure (IOP), based on a novel wireless contact lens sensor (CLS). Methods:, The wireless CLS is a disposable silicone soft contact lens with a sensor embedded in it, allowing the wireless measurement of changes in corneal curvature induced by IOP variations. A CLS was adapted and tested on enucleated pig eyes. To demonstrate the measurement principle of the device, the enucleated pig eye was cannulated, allowing precise control of IOP. The CLS signal was then compared to the imposed IOP. Results:, First, the IOP of enucleated pig eyes was changed between 11 and 14 mmHg, simulating ocular pulsation. Then, IOP was changed with static steps of 1 mmHg between 20 and 30 mmHg to assess the reproducibility and linearity of the CLS. In both cases, measurements from the CLS and IOP showed very good correlation. A calibration graph shows that the CLS is capable of monitoring the IOP of each individual eye with a reproducibility of ± 0.2 mmHg (95% confidence interval). Conclusion:, The wireless CLS shows a good functionality to monitor the IOP on enucleated pig eyes. The device is placed in the same way as a soft disposable contact lens. This device would allow a minimally invasive and continuous monitoring of IOP over prolonged periods of up to 24 hr, regardless of patient activity, thus opening up new diagnostic and therapeutic methods to manage glaucoma. [source] | |||||||||||||||||||