831 resultados para Angle of 95% confidence


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The contents of some nutrients in 35 Brazilian green and roasted coffee samples were determined by flame atomic absorption spectrometry (Ca, Mg, Fe, Cu, Mn, and Zn), flame atomic emission photometry (Na and K) and Kjeldahl (N) after preparing the samples by wet digestion procedures using i) a digester heating block and ii) a conventional microwave oven system with pressure and temperature control. The accuracy of the procedures was checked using three standard reference materials (National Institute of Standards and Technology, SRM 1573a Tomato Leaves, SRM 1547 Peach Leaves, SRM 1570a Trace Elements in Spinach). Analysis of data after application of t-test showed that results obtained by microwave-assisted digestion were more accurate than those obtained by block digester at 95% confidence level. Additionally to better accuracy, other favorable characteristics found were lower analytical blanks, lower reagent consumption, and shorter digestion time. Exploratory analysis of results using Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) showed that Na, K, Ca, Cu, Mg, and Fe were the principal elements to discriminate between green and roasted coffee samples. ©2007 Sociedade Brasileira de Química.

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This paper describes a simple, portable and environmentally friendly method for the rapid determination of dipyrone in pharmaceuticals by using diffuse reflectance spectroscopy. The proposed method is based on the reflectance measurements of the orange compound produced from the spot test reaction between dipyrone and p-dimethylaminocinnamaldehyde (p-DAC), in acid medium, using a filter paper as solid support. Experimental design methodologies were used to optimize the measurement conditions. All reflectance measurements were carried out at 510 nm and the linear range was from 1.42 × 10-4-2.85 × 10-3 mol L-1, with a correlation coefficient of 0.999. The limit of detection (LOD) and the limit of quantification (LOQ) were 1.20 × 10-5 mol L-1 and 4.00 × 10-5 mol L-1, respectively. The intraday precision and interday precision were studied for 10 replicate analyses of 7.90 × 10-4 mol L-1 dipyrone solution. The coefficients of variation were 1.1 and 0.9%, respectively. The proposed method was applied successfully to the determination of dipyrone in commercial brands of pharmaceuticals. No interferences were observed from the common excipients in formulations. The results obtained by the proposed method were favorably compared with those given by the Brazilian Pharmacopoeia procedure at 95% confidence level. ©2007 Sociedade Brasileira de Química.

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We search for decays of Kaluza-Klein excitations of the graviton in the Randall-Sundrum model of extra dimensions to e+e- and in 1 fb-1 of pp collisions at s=1.96 TeV collected by the D0 detector at the Fermilab Tevatron. We set 95% confidence level upper limits on the production cross section times branching fraction, which translate into lower limits on the mass of the lightest excitation between 300 and 900 GeV for values of the coupling k/M Pl between 0.01 and 0.1. © 2008 The American Physical Society.

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A simple, rapid and sensitive spectrophotometric method has been developed for the determination of methyldopa in pharmaceutical formulations. The method is based on the reaction between tetrachloro-p-benzoquinone (p-chloranil) and methyldopa, accelerated by hydrogen peroxide (H 2O 2), producing a violet-red compound (λmax = 535 nm) at ambient temperature (25.0 ± 0.2°C). Experimental design methodologies were used to optimize the measurement conditions. Beer's law is obeyed in a concentration range from 2.10 × 10 -4 to 2.48 × 10 -3 mol L -1 (r = 0.9997). The limit of detection was 7.55 × 10 -6 mol L -1 and the limit of quantification was 2.52 × 10 -5 mol L -1. The intraday precision and interday precision were studied for 10 replicate analyses of 1.59 × 10 -3 mol L -1 methyldopa solution and the respective coefficients of variation were 0.7 and 1.1%. The proposed method was successfully applied to the determination of methyldopa in commercial brands of pharmaceuticals. No interferences were observed from the common excipients in the formulations. The results obtained by the proposed method were favorably compared with those given by the Brazilian Pharmacopoeia procedure at 95% confidence level.

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Electromyography is frequently used to measure the activity of masticatory muscles. It requires the precise setting of the electrodes, which demands the accurate location of the muscle to be evaluated. The purpose of this study was to investigate the accuracy of an external method to locate the buccinator muscle. Fifteen human cadavers were evaluated and planes were etermined on the face using anatomic landmarks. An angle (α) was obtained at the intersection of these planes on the central point of buccinator muscle and measured with a protractor. The value of the angle allows locating the central point of buccinator muscle based on anatomic landmarks on the face. Statistical analysis of the collected data indicated an angle of 90° with 95% reliability, thus proving the efficacy of the proposed method.

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Background: Health-related quality of life (HRQOL) measurements provide valuable information about the psychological and social impact of treatment on patients with cystic fibrosis (CF). This study evaluated the HRQOL of Brazilian patients with CF and assessed the changes in HRQOL domains over 1 year after dornase alfa (Pulmozyme) introduction. Patients and Methods: One hundred fifty-six stable patients with CF and 89 caregivers answered the Portuguese-validated version of the Cystic Fibrosis Questionnaire-Revised (CFQ-R) at baseline (T 0), and at 3 (T 1), 6 (T 2), 9 (T 3), and 12 (T 4) months of follow-up. Eighteen patientswere excluded because they did not fulfill the inclusion criteria. The patients were analyzed in two groups: those aged 6-11 years and those aged 14 years and older. ANOVA for observed repeated results and the last observation carried forward (LOCF) method for missing data were used for the statistical analysis. Results: After 1 year of follow-up, there was significant improvement in respiratory symptoms (T 4-T 0=8.1; 95% confidence interval (95% CI)=[2.1;14.0]; effect size (ES)=0.35; P<0.001), Emotional Functioning (T 4-T 0=5.6; 95% CI=[1.1;10.1]; ES=0.31; P<0.05), Social Functioning (T 4-T 0=6.0; 95% CI=[1.3;11.7]; ES=0.31; P<0.05), Body Image (T 4-T 0=11.9; 95% CI=[4.1;19.7]; ES=0.42; P<0.05), and Treatment Burden (T 4-T 0=5.3; 95% CI=[0.3;10.3]; ES=0.24; P<0.05) domains in the younger group. A significant improvement in Role Functioning (T 4-T 0=6.1; 95% CI=[1.1;11.1]; ES=0.40; P<0.05), Body Image (T 4-T 0=12.6; 95% CI=[3.5;21.7]; ES=0.46; P<0.05), and Weight (T 4-T 0=11.7; 95% CI=[1.8;21.6]; ES=0.40; P<0.05) was obtained in the older group. The caregivers' CFQ-R showed improvements in the Digestive Symptoms (T 4-T 0=5.5; 95% CI=[1.5;9.4]; ES=0.30; P<0.05), Respiratory Symptoms (T 4-T 0=7.6; 95% CI=[3.9;11.4]; ES=0.48; P<0.05), and Weight (T 4-T 0=10.1; 95% CI=[1.6;18.6]; ES=0.26; P<0.05) domains. Conclusion: The introduction of dornase alfa improved the HRQL of the patients with CF during the first year of treatment. © 2010 Wiley-Liss, Inc.

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This study compared the sampling efficacy cia cytobrush and metal spatula for exfoliative cytology of the oral mucosa. Thirty students with no detectable oral alterations upon clinical examination were submitted to exfoliative cytology of the lateral border of the tongue, using a metal spatula on the left side and a cytobrush on the right side. The smears were stained using the Papanicoiaou technique and evaluated for cellularity, cell type, cell distribution, homogeneity, and cellular distortion, as well as the presence ol mucus, inflammatory infiltrate, and hemorrhage. A statistical test (Z-test) with a 95% confdence interval (Cl) showed a significant difference between the metal spatula and cytobrush in terms of cellularity (p = 0.02) and homogeneity (p = 0.01). No difference between the two methods was observed regarding cell type (p = 0.4, Z-test) or cell distribution for the 95% confidence interval (p = 0.2, Fisher's test). Cell distortion and the presence of mucus were observed in five cases that used the metal spatula and in two cases that used the cytobrush. No hemorrhage or inflammatory infItrate was detected in any of the slides. Based on the results of this study, the cytobrush produced qualitatively better smears in terms of cellularity and homogeneity compared to the metal spatula.

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A simple, rapid, accurate and inexpensive spectrophotometric method for the determination of tetracycline and doxycycline has been developed. The method is based on the reaction between these drugs and chloramine-T in alkaline medium producing red color products with absorbance maximum at the λ=535 and 525 nm for the tetracycline and doxycycline, respectively. The best conditions for the reactions have been found using multivariate method. Beer's law is obeyed in a concentration ranges 1. 03 x 10 -5 to 3. 61 x 10 4mol L -1 and 1. 75 x 10 -5 to 3. 48 x 10 4mol L -1 for the tetracycline and doxycycline, respectively. The quantification limits were 5. 63 x 10 -6 mol L -1 and 7. 12 x 10 -7 mol L -1 for the tetracycline and doxycycline, respectively. The proposed method was successfully applied to the determination of these drugs in pharmaceutical formulations and the results obtained were in good agreement with those obtained by the comparative method at the 95% confidence level.

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We present a search for associated production of Higgs and W bosons in pp̄ collisions at a center of mass energy of s=1.96 TeV in 5.3 fb-1 of integrated luminosity recorded by the D0 experiment. Multivariate analysis techniques are applied to events containing one lepton, an imbalance in transverse energy, and one or two b-tagged jets to discriminate a potential WH signal from Standard Model backgrounds. We observe good agreement between data and expected backgrounds, and set an upper limit of 4.5 (at 95% confidence level and for mH=115 GeV) on the ratio of the WH cross section multiplied by the branching fraction of H→bb̄ to its Standard Model prediction, which is consistent with an expected limit of 4.8. © 2011 Elsevier B.V.

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A simple method to determine Cu, Fe, Mn and Zn in single aliquots of medicinal plants by HR-CS FAAS is proposed. The main lines for Cu, Mn and Zn, and the alternate line measured at the wing of the main line for Fe at 248.327 nm allowed calibration within the 0.025 - 2.0 mg L-1 Cu, 1.0 - 20.0 mg L-1 Fe, 0.05 - 2.0 mg L-1 Mn, 0.025 - 0.75 mg L-1 Zn ranges. Nineteen medicinal plants and two certified plant reference materials were analyzed. Results were in agreement at a 95% confidence level (paired t-test) with reference values. Limits of detection were 0.12 μg L-1 Cu, 330 μg L-1 Fe, 1.42 μg L-1 Mn and 8.12 μg L-1 Zn. Relative standard deviations (n=12) were ≤ 3% for all analytes. Recoveries in the 89 - 105% (Cu), 95 - 108% (Fe), 94 - 107% (Mn), and 93 - 110% (Zn) ranges were obtained.

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This paper describes a simple, environmentally friendly and rapid quantitative spot test procedure for the determination of captopril (CPT) in bulk drug and in pharmaceutical formulations by using diffuse reflectance spectroscopy. The proposed method is based on the reflectance measurements of the orange compound (λ max 490 nm) produced by the spot test reaction between CPT and p-chloranil (CL). Under optimal conditions, calibration curves were obtained for CPT by plotting the optical density of the reflectance signal (A R) vs. the log of the mol L -1 concentration, from 6.91×10 -3 to 1.17×10 -1, with a good coefficient of determination (R 2 = 0.9992). The common excipients used as additives in pharmaceuticals do not interfere in the proposed method. The method was applied to determine CPT in commercial pharmaceutical formulations. The results obtained by the proposed method are compared favorably with those obtained by an official procedure at 95% confidence level. The method validation results showed that the sensitivity and selectivity of the methods were adequated for drug monitoring in industrial quality control laboratories. © 2011 Moment Publication.

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Results are presented from a search for heavy bottom-like quarks, pair-produced in pp collisions at √s = 7TeV, undertaken with the CMS experiment at the LHC. The b′ quarks are assumed to decay exclusively to tW. The b′b̄′ → tW-t̄W+ process can be identified by its distinctive signatures of three leptons or two leptons of same charge, and at least one b-quark jet. Using a data sample corresponding to an integrated luminosity of 4.9 fb-1, observed events are compared to the standard model background predictions, and the existence of b′ quarks having masses below 611 GeV/c2 is excluded at 95% confidence level.

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Objective: To verify, in extremely preterm infants, if disagreement between obstetricians and neonatologists regarding proactive management is associated with early death.Study Design: Prospective cohort of 484 infants with 23 0/7 to 266/7 weeks, without malformations, born from January 2006 to December 2009 in eight Brazilian hospitals. Pro-active management was defined as indication of ≥1 dose of antenatal steroid or cesarean section (obstetrician) and resuscitation at birth according to the international guidelines (neonatologist). Main outcome was neonatal death in the first 24 h of life.Result: Obstetricians and neonatologists disagreed in 115 (24%) patients: only neonatologists were proactive in 107 of them. Disagreement between professionals increased 2.39 times the chance of death in the first day (95% confidence interval 1.40 to 4.09), adjusted for center and maternal/neonatal clinical conditions.Conclusion: In infants with 23 to 26 weeks of gestation, disagreement between obstetricians and neonatologists, translated as lack of antenatal steroids and/or vaginal delivery, despite resuscitation procedures, increases the odds of death in the first day. © 2012 Nature America, Inc.

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Purpose: This study was performed to compare the inverted digital images and film-based images of dry pig mandibles to measure the periodontal bone defect depth. Materials and Methods: Forty 2-wall bone defects were made in the proximal region of the premolar in the dry pig mandibles. The digital and conventional radiographs were taken using a Schick sensor and Kodak F-speed intraoral film. Image manipulation (inversion) was performed using Adobe Photoshop 7.0 software. Four trained examiners made all of the radiographic measurements in millimeters a total of three times from the cementoenamel junction to the most apical extension of the bone loss with both types of images: inverted digital and film. The measurements were also made in dry mandibles using a periodontal probe and digital caliper. The Student's t-test was used to compare the depth measurements obtained from the two types of images and direct visual measurement in the dry mandibles. A significance level of 0.05 for a 95% confidence interval was used for each comparison. Results: There was a significant difference between depth measurements in the inverted digital images and direct visual measurements (p>|t|=0.0039), with means of 6.29 mm (IC95%:6.04-6.54) and 6.79 mm (IC95%:6.45-7.11), respectively. There was a non-significant difference between the film-based radiographs and direct visual measurements (p>|t|=0.4950), with means of 6.64mm (IC95%:6.40-6.89) and 6.79mm(IC95%:6.45-7.11), respectively. Conclusion: The periodontal bone defect measurements in the inverted digital images were inferior to film-based radiographs, underestimating the amount of bone loss. copy; 2012 by Korean Academy of Oral and Maxillofacial Radiology.

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Objective: The impact of obesity on ventricular remodeling after myocardial infarction (MI) is still poorly understood. Therefore, the aim of this study was to evaluate the role of waist circumference (WC) and body mass index as predictors of cardiac remodeling in patients after an anterior MI. Methods: Eighty-three consecutive patients with anterior MI were prospectively evaluated. Clinical characteristics and echocardiographic data were analyzed at admission and at a 6-mo follow-up. Ventricular remodeling was defined as a 10% increase in left ventricular end-systolic or end-diastolic diameter at the 6-mo follow-up. Results: In our study, 83 consecutive patients were evaluated (72% men). Ventricular remodeling was present in 31% of the patients (77% men). Patients with remodeling had higher creatine phosphokinase and creatine phosphokinase-MB peak values, a higher resting heart rate, a larger left atrial diameter, and a larger interventricular septum diastolic thickness. In addition, patients with remodeling had lower peak velocity of early ventricular filling deceleration time and ejection fraction. Patients with remodeling presented higher WC values (with remodeling, 99.2 ± 10.4 cm; without remodeling, 93.9 ± 10.8 cm, P = 0.04), but there were no differences in the body mass index values. In the logistic regression analysis, WC, adjusted by age, gender, ejection fraction, and creatine phosphokinase levels, was an independent predictor of left ventricular remodeling (odds ratio 1.067, 95% confidence interval 1.001-1.129, P = 0.02). Conclusion: Waist circumference, but not body mass index, is a predictor of ventricular remodeling after an anterior MI. Therefore, the WC of these patients should be measured in clinical practice. © 2013 Elsevier Inc.