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Standard Deviation (standard + deviation)
Kinds of Standard Deviation Terms modified by Standard Deviation Selected AbstractsPredictors of Long-Term Risk for Heart Failure Hospitalization after Acute Myocardial InfarctionANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2010Juha S. Perkiömäki M.D. Background: Data on the value of baseline brain natriuretic peptide (BNP) and autonomic markers in predicting heart failure (HF) hospitalization after an acute myocardial infarction (AMI) are limited. Methods: A consecutive series of patients with AMI without a previous history of HF (n = 569) were followed up for 8 years. At baseline, the patients had a blood sample for determination of BNP, a 24-hour Holter recording for evaluating heart rate variability (HRV) and heart rate turbulence (HRT), and an assessment of baroreflex sensitivity (BRS) using phenylephrine test. Results: During the follow-up, 79 (14%) patients were hospitalized due to HF. Increased baseline BNP, decreased HRV, HRT, and BRS had a significant association with HF hospitalization in univariate comparisons (P < 0.001 for all). After adjusting with all the relevant clinical parameters, BNP, HRV, and HRT still significantly predicted HF hospitalization (P < 0.001 for BNP and for the short-term scaling exponent ,1, P < 0.01 for turbulence slope). In the receiver operator characteristics curve analysis, the area under the curve for BNP was 0.77, for the short-term scaling exponent ,1 0.69, for turbulence slope 0.71, and for BNP/standard deviation of all N-N intervals ratio 0.80. Conclusion: Baseline increased BNP and impaired autonomic function after AMI yield significant information on the long-term risk for HF hospitalization. Ann Noninvasive Electrocardiol 2010;15(3):250,258 [source] 4351: Using the OHTS-EGPS risk calculator with OctopusTM visual field testingACTA OPHTHALMOLOGICA, Issue 2010AM STEVENS Purpose Assessing risk in ocular hypertensive (OHT)patients is not only of clinical importance for the patients with regard to their possible glaucomatous field damage but has major repercussions on their quality of life when making decisions about the use of eye drops for longer periods. Clinicians are not that good in estimating the risk hence the need for instruments to help them make a more evidence-based decision. The EGPS group states that a methodological difference " of using in a quarter of the patients another type of perimeter could explain the Hasard Ratio for the Pattern Standard Deviation (PSD) of 1.66 in EGPS and 1.27 in OHTS . Hence our interest to recalculate a conversion of the Octopus G1 program ( mostly used for glaucoma ) to the Humphrey 30-2 in a Group of ocular hypertensives conform the inclusions of the OHTS thus providing a way to use the calculator more accurately. Methods 50 OHT patients recruited using the OHTS criteria were tested both with the Humphrey 30-2 program and the Octopus G1 program. The Humphrey PSD values were plotted against the square root of the Loss of Variance (sLV) and a conversion formula was calculated Results Our data generated the following conversion formula: Y = 0.4X + 1.1 Conclusion Our conversion permits a proper use of the risk calculator in OHT patients. There has been an attempt to convert the values from Humphrey 30-2 to Octopus 32 by Monhart based on the results of a study by Langerhorst. Another approach could be based on the algorithm described by Zeyen using HFA 24-2 and G1 Octopus but proves difficult to use in daily practice. EGPS simply used "converted" indices by taking the square root of LV for PSD. Our formula is based on the same population as OHTS but yields different results [source] Implied Standard Deviations and Post-earnings Announcement VolatilityJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 3-4 2002Daniella Acker This paper investigates volatility increases following annual earnings announcements. Standard deviations implied by options prices are used to show that announcements of bad news result in a lower volatility increase than those of good news, and delay the increase by a day. Reports that are difficult to interpret also delay the volatility increase. This delay is incremental to that caused by reporting bad news, although the effect of bad news on slowing down the reaction time is dominant. It is argued that the delays reflect market uncertainty about the implications of the news. [source] Comparison of insulin lispro protamine suspension and insulin detemir in basal-bolus therapy in patients with Type 1 diabetesDIABETIC MEDICINE, Issue 5 2010A. R. Chacra Diabet. Med. 27, 563,569 (2010) Abstract Aims, The efficacy of two basal insulins, insulin lispro protamine suspension (ILPS) and insulin detemir, was compared in basal-bolus regimens in Type 1 diabetes. Methods, In this 32-week, multinational, parallel-group, randomized, controlled trial, adult patients with Type 1 diabetes received ILPS or insulin detemir, injected twice daily (before breakfast and bedtime) and prandial insulin lispro three times daily. The primary outcome was change in glycated haemoglobin (HbA1c) from baseline to endpoint. Results, Least squares mean (±se) changes in HbA1c were similar between groups, meeting non-inferiority (margin, 0.4%): ,0.69 ± 0.07% for ILPS and ,0.59 ± 0.07% for insulin detemir [between-treatment difference ,0.10%; 95% confidence interval (CI) ,0.29, 0.10]. Standard deviation of fasting blood glucose was similar (non-inferiority margin 0.8 mmol/l): 2.74 ± 0.14 mmol/l for ILPS and 2.38 ± 0.14 mmol/l for insulin detemir (CI ,0.03, 0.75). Patients on ILPS gained more weight (1.59 ± 0.23 kg vs. 0.62 ± 0.24 kg; CI 0.34, 1.60; margin 1.5 kg). Weight-adjusted daily total and prandial insulin doses were lower for ILPS (prandial insulin, 0.38 ± 0.01 U/kg/day for ILPS, 0.44 ± 0.01 U/kg/day for insulin detemir; P = 0.004); daily basal insulin dose was similar. All hypoglycaemia incidence and rate and nocturnal hypoglycaemia incidence were similar between groups; nocturnal hypoglycaemia rate was lower for insulin detemir (mean ± sd 0.79 ± 1.23 for ILPS, 0.49 ± 0.85 for insulin detemir; P = 0.001). Severe hypoglycaemia rate was 0.03 ± 0.11 for ILPS and 0.02 ± 0.10 for insulin detemir (P = 0.37). Conclusions, ILPS-treated patients with Type 1 diabetes achieved similar glycaemic control as insulin detemir-treated patients after 32 weeks. Glucose variability was similar. While weight gain and nocturnal hypoglycaemia rate were statistically higher with ILPS, the clinical relevance is unclear. [source] Body Dimensions of Infants Exposed to Antiepileptic Drugs In Utero: Observations Spanning 25 YearsEPILEPSIA, Issue 7 2000K. Wide Summary: Purpose: To investigate the influence of maternal antiepileptic drug (AED) treatment on pregnancy duration, birth weight, body length, head circumference, and intrauterine growth in infants exposed in utero to antiepileptic drugs in Sweden between 1973,1997, with 963 singleton infants. Methods: Data collected from (a) 1973,1981 (record linkage between a hospital discharge register and a medical birth register); (b) 1984,1995 (prospectively collected information in one defined catchment area with two delivery hospitals); and (c) 1995,1997 (medical birth register data). Observed numbers of infants below a defined size for body measurements compared with expected numbers calculated from all births in Sweden after stratification for year of birth, maternal age, parity, and education or smoking habits in early pregnancy. Standard deviation scores estimated with same stratification procedures. Results: Fraction of monotherapy exposures increased from ,40% to ,90% from 1973 to 1997. Significantly increased numbers of infants with small body measurements found in exposed group. Negative influence on body dimensions decreased over time. More marked effects found in infants exposed to polytherapy. In monotherapy, only infants exposed to carbamazepine consistently showed reduction in body dimensions. Significant effect on gestational age in girls and on number of small for gestational age (<2 SD) in boys. Conclusions: Polytherapy with antiepileptic drugs and negative influence on body dimensions decreased. In monotherapy, only carbamazepine has a negative influence on body dimensions in this study. [source] Left Atrial Ablation at the Anatomic Areas of Ganglionated Plexi for Paroxysmal Atrial FibrillationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2010EVGENY POKUSHALOV M.D., Ph.D. Background:,Modification of left atrial ganglionated plexi (GP) is a promising technique for the treatment of paroxysmal atrial fibrillation (AF) but its therapeutic efficacy is not established. This study aimed at evaluating the effectiveness of anatomic GP modification by means of an implantable arrhythmia monitoring device. Methods:,In 56 patients with paroxysmal AF, radiofrequency ablation at anatomic sites, where the main clusters of GP have been identified in the left atrium, was performed. In all patients, an electrocardiogram monitor (Reveal XT, Medtronic Inc., Minneapolis, MN, USA) was implanted before (n = 7) or immediately after (n = 49) AF ablation. Results:,Average duration of the procedure was 142 ± 18 min and average fluoroscopy time 20 ± 7 min. In total, 53,81 applications of RF energy were delivered (mean of 18.2 ± 3.8 at each of the four areas of GP ablation). Heart rate variability was assessed in 31 patients. Standard deviation of RR intervals over the entire analyzed period, the root mean square of differences between successive RR intervals, and high frequencies decreased, while HRmin, HRmean, and LF to HF ratio increased immediately postablation; these values returned to baseline 6 months after the procedure. At end of 12-month follow-up, 40 (71%) patients were free of arrhythmia recurrence. Ten patients had AF recurrence, two patients had left atrial flutter, and four patients had episodes of flutter as well as AF recurrence. Duration of episodes of AF after ablation gradually decreased over the follow-up period. Conclusions:,Regional ablation at the anatomic sites of the left atrial GP can be safely performed and enables maintenance of sinus rhythm in 71% of patients with paroxysmal AF for a 12-month period. (PACE 2010; 33:1231,1238) [source] The influence of age on gait parameters during the transition from a wide to a narrow pathwayPHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 2 2008Nataliya Shkuratova Abstract Background and Purpose.,The ability to negotiate pathways of different widths is a prerequisite of daily living. However, only a few studies have investigated changes in gait parameters in response to walking on narrow pathways. The aim of this study is to examine the influence of age on gait adjustments during the transition from a wide to a narrow pathway.,Method.,DESIGN: Two-group repeated measures design. SETTING: Gait Laboratory. PARTICIPANTS: Twenty healthy older participants (mean [M] = 74.3 years, Standard deviation [SD] = 7.2 years); 20 healthy young participants (M = 26.6 years, SD = 6.1 years).,Interventions.,Making the transition from walking on a wide pathway (68,cm) to walking on a narrow pathway (15,cm). MAIN OUTCOME MEASURES: Step length, step time, step width, double support time and base of support. Results.,Healthy older participants were able to make the transition from a wide to a narrow pathway successfully. There was only one significant interaction, between age and base of support (p < 0.003). Older adults decreased their base of support only when negotiating the transition step, while young participants started decreasing their base of support prior to the negotiation of transition step (p < 0.01). Conclusion.,Adjustments to the transition from a wide to a narrow pathway are largely unaffected by normal ageing. Difficulties in making the transition to a narrow pathway during walking should not be attributed to normal age-related changes. Copyright © 2008 John Wiley & Sons, Ltd. [source] Analysis of the 13C natural abundance of CO2 gas from sparkling drinks by gas chromatography/combustion/isotope ratio mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 5 2005Giovanni Calderone A simple and rapid method to measure naturally occurring ,13C values of headspace CO2 of sparkling drinks has been set up, using direct injections on a gas chromatograph coupled to an isotope ratio mass spectrometer, through a combustion interface (GC/C/IRMS). We tested the method on CO2 gas from several origins. No significant isotopic fractionation was observed nor influences by secondary compounds eventually present in the gas phase. Standard deviation for these measurements was found to be <0.1,. Copyright © 2005 John Wiley & Sons, Ltd. [source] Optical aberration measurements in dog and cat eyes: interest & limitACTA OPHTHALMOLOGICA, Issue 2008SG ROSOLEN Purpose To measure the ocular optical aberrations in dog and cat using a wavefront aberrometer based on Hartmann-Shack technology. Methods Two dogs and one cat were sedated (Medetomidine, 0.1 mg/kg) and their right eye (RE) pupils were artificially dilated (tropicamide). Wavefront aberrations were measured using an irx3 aberrometer (Imagine Eyes, Orsay, France). Prior to each measurement, the eye was aligned with the instrument optical axis by centering both the eye pupil and Purkinje images. The Hartmann-Shack spot images were produced by an array of 1024 microlenses that defined a 7.2x7.2 mm square area in the pupil plane. In preliminary tests, spot image histograms were optimized by adjusting the sensor acquisition time. Wavefront aberrations were then repeatedly measured 10 times in each animal's RE. Spherical defocus, astigmatism and Zernike coefficients up to the 8th order were finally analyzed. Results The optimal acquisition time was 10 ms for all animals, instead of 33 ms when measuring human eyes. Refractive errors could be analyzed in a 6 mm pupil diameter in all cases. The dilated pupil often exceed the sensor area. The average refractive errors in dog #1, dog #2 and the cat were +2.9D(-2.0D)111°;-0.8D(-0.8D)126° and +3.3D(-2.1D)98°, respectively while their Root Mean Square (RMS) higher-order aberrations amounted to 1.9, 1.1, and 2.1 µm RMS respectively. Standard deviation in sphere and cylinder was 1.0D in the cat and less than 0.5D in both dogs. Standard deviation in the higher-order RMS was 0.8 µm in the cat and less than 0.5 µm in both dogs. The observation of individual data revealed that a significant part of this variability was due to blink-related changes in aberrations. Conclusion Ocular optical aberrations can be easily measured in dog and cat using a Hartmann-Shack aberrometer with reduced image acquisition time. The tested animals had relatively large higher-order wavefront aberrations when compared to date measured in healthy human eyes. Measurement reproducibility was notably affected by tear layer effects. This variability could probably be reduced using a larger sensor area, specific head contention device and artificial tears. This new diagnostic technique is easily feasible without any use of anaesthesia and provides less variability and more detailed information than skiascopy. Wavefront aberrometry could be useful in both research and clinical applications. [source] Dynamic wavefront aberrations and visual acuity in normal and dry eyesCLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 3 2009Yan Wang MD Purpose:, The aim was to study the dynamic properties of wavefront aberrations and visual acuity in normal and dry eyes. Methods:, Thirty dry-eye patients and 27 normal subjects participated in this study. Multi-file mode of a Hartmann-Shack wavefront sensor was used to measure dynamic wavefront aberrations for a period of 45 seconds. Dynamic measurements of visual acuity (VA) were made for 150 seconds using a multi-functional VA tester. Standard deviation of the measurements (RMS or VA) over the testing period was used to estimate instability of the dynamic wavefront aberration and VA. Results:, For most subjects, both wavefront aberration and VA changed over time and the instability varied substantially among individuals. Blink-dependent fluctuation in wavefront aberration or VA was observed for some dry-eye subjects. On average, the dry-eye group had greater instability than the normal group in either the higher order wavefront aberrations (t = 2.09, p = 0.03, for OD; t = 3.76, p = 0.001, for OS) or the VA (t = 2.09, p = 0.02, for OD; t = 204, p = 0.03, for OS). Instability of VA in the dry-eye group was significantly correlated with blink rate (r = 0.28, p = 0.02). Conclusion:, Dynamic changes in wavefront aberrations and VA are highly individual dependent, while the dry eye tends to be less stable than the normal eye. The results suggest that tear-film fluctuation might play a role in determining dynamic wavefront aberration and VA, however, contributions from other factors should not be overlooked. For dry eye, dynamic change in VA depends on blink rate. [source] Idiographically Determined Versus Standard Absorption Periods in Alcohol Administration StudiesALCOHOLISM, Issue 5 2010Rebecca L. Schacht Background:, Effects of alcohol vary depending on blood alcohol level and limb. Some researchers use standard absorption periods (SAPs) to determine when postdrinking experimental protocols should begin. Others use an idiographically determined absorption period (IDAP) based on criterion breath alcohol concentration (BrAC). We investigated and compared the characteristics of each method. Methods:, Sixty-eight social drinkers (47% women) consumed a bolus dose of alcohol intended to raise BrAC to 0.08%. BrACs were recorded every 3 minutes until beginning to descend. Minutes to reach criterion BrAC (0.06%) and between-subjects postdrinking BrAC variability were analyzed. Results:, Mean time to reach 0.06% BrAC was 22.9 ± 14.6 minutes. Standard deviations in BrAC were 4 times greater using SAPs compared to IDAPs. Ten percent of participants' BrAC readings were on the descending limb 30 minutes postdrinking, and 25% were descending at 45 minutes postdrinking. Conclusions:, IDAPs result in less BrAC variability and may reduce experimental noise relative to SAPs. Experimental control in future alcohol administration studies may be enhanced by the use of IDAPs instead of SAPs. [source] Fragmentation model of meteoroid motion, mass loss, and radiation in the atmosphereMETEORITICS & PLANETARY SCIENCE, Issue 1 2005k CEPLECHA We solve them numerically including two possible types of fragmentation: into large pieces and into a cluster of small fragments. We have written a Fortran code that computes the motion, ablation and light intensity of a meteoroid at chosen heights, and allows for the ablation and shape density coefficients , and K, as well as the luminous efficiency ,, to be variable with height/time. We calibrated our fragmentation model (FM) by the best fit to observational values for the motion, ablation, radiation, fragmentation and the terminal masses (recovered meteorites) for the Lost City bolide. The FM can also handle multiple and overlapping meteor flares. We separately define both the apparent and intrinsic values of ,, K, and ,. We present in this paper values of the intrinsic luminous efficiency as function of velocity, mass, and normalized air density. Detailed results from the successful application of the FM to the Lost City, Innisfree, and Benesov bolides are also presented. Results of applying the FM to 15 bolides with very precise observational data are presented in a survey mode (Table 7). Standard deviations of applying our FM to all these events correspond to the precision of the observed values. Typical values of the intrinsic ablation coefficient are low, mostly in the range from 0.004 to 0.008 s2 km,2, and do not depend on the bolide type. The apparent ablation coefficients reflect the process of fragmentation. The bolide types indicate severity of the fragmentation process. The large differences of the "dynamic" and "photometric" mass from numerous earlier studies are completely explained by our FM. The fragmentation processes cannot be modeled simply by large values of the apparent ablation coefficient and of the apparent luminous efficiency. Moreover, our new FM can also well explain the radiation and full dynamics of very fast meteoroids at heights from 200 km to 130 km. [source] Evaluation of foliar resistance in potato to Phytophthora infestans based on an international field trial networkPLANT PATHOLOGY, Issue 2 2005J. G. Hansen During the period 2000,03, local potato cultivars in Estonia, Latvia, Lithuania, Poland and Denmark were tested for foliar resistance to Phytophthora infestans (late blight) in an international field trial network. Four standard cultivars were included in the trials: Sava, Oleva, Danva and Kuras. Primary disease-assessment data were entered into a common database, and parameters from the disease progress curves were calculated and made available on interactive web pages. A regression model, using relative area under disease progress curve (RAUDPC) values for cv. Oleva as a reference, was developed for the estimation of 1,9 scale values, where 1 = most susceptible. Standard deviations for the estimated 1,9 scale values and a nonparametric rank stability analysis of RAUDPC were used to evaluate the stability of resistance of the cultivars. Overall, the results showed stability of resistance for cvs Sava, Oleva and Danva, but not for Kuras. Use of the Internet-based Web-Blight service in this study facilitated comparison of results among countries for the level and stability of resistance. The estimated 1,9 scale values were similar to, or slightly lower than, those from official cultivar lists or from the European Cultivated Potato Database, especially for the more resistant cultivars. Possible reasons for discrepancies from different sources and locations are discussed. It is concluded that RAUPDC and the derived 1,9 scale values are useful for ranking cultivars for resistance to P. infestans, but this information is not detailed enough for use in a decision support system for late blight control. [source] New reference for the age at childhood onset of growth and secular trend in the timing of puberty in SwedishACTA PAEDIATRICA, Issue 6 2000YX Liu The objectives of the present work were to present a new reference for the age at childhood onset of growth and to investigate the secular trend in the timing of puberty in a community-based normal population in Sweden. A total of 2432 children with longitudinal length/height data from birth to adulthood were used to determine the two measures by visual inspection of the measured attained length/height and the change in growth velocity displayed on a computer-generated infancy-childhood-puberty (ICP) based growth chart. The series represents a sample of normal full-term children born around 1974 in Göteborg, Sweden. We found about 10% of children were delayed (>12 mo of age) in the childhood onset of growth based on the previous reported normal range, i.e. 14% in boys and 8% in girls. Distribution of the age at childhood onset of growth was skewed. The medians were 10 and 9 mo for boys and girls, respectively. After natural logarithmic transformation, the mean and standard deviation (SD) were 2.29 (anti-log 9.9 mo) and 0.226 for boys, 2.23 (anti-log 9.3 mo) and 0.220 for girls, respectively. The 95% normal ranges were 6.3-15.4 and 6.0-14.3 for boys and girls, respectively. The distribution of the timing of PHV was close to the normal distribution. The mean values were 13.5 y for boys and 11.6 y for girls with 1 y SD for both sexes. Conclusion: A downward secular trend in the onset of puberty was clearly shown in the population. The age at childhood onset of growth did not correlate with the timing of puberty (r=,0.01 and 0.05, p > 0.7 and 0.1 in boys and girls, respectively). Normal ranges of the age at childhood onset of growth are in need of revise, as this study indicates. The new reference presented here could be a reliable indicator in further studies. [source] Using Logistic Regression to Analyze the Sensitivity of PVA Models: a Comparison of Methods Based on African Wild Dog ModelsCONSERVATION BIOLOGY, Issue 5 2001Paul C. Cross Standardized coefficients from the logistic regression analyses indicated that pup survival explained the most variability in the probability of extinction, regardless of whether or not the model incorporated density dependence. Adult survival and the standard deviation of pup survival were the next most important parameters in density-dependent simulations, whereas the severity and probability of catastrophe were more important during density-independent simulations. The inclusion of density dependence decreased the probability of extinction, but neither the abruptness nor the inclusion of density dependence were important model parameters. Results of both relative sensitivity analyses that altered each parameter by 10% of its range and life-stage-simulation analyses of deterministic matrix models supported the logistic regression results, indicating that pup survival and its variation were more important than other parameters. But both conventional sensitivity analysis of the stochastic model which changed each parameter by 10% of its mean value and elasticity analyses indicated that adult survival was more important than pup survival. We evaluated the advantages and disadvantages of using logistic regression to analyze the sensitivity of stochastic population viability models and conclude that it is a powerful method because it can address interactions among input parameters and can incorporate the range of parameter variability, although the standardized regression coefficients are not comparable between studies. Model structure, method of analysis, and parameter uncertainty affect the conclusions of sensitivity analyses. Therefore, rigorous model exploration and analysis should be conducted to understand model behavior and management implications. Resumen: Utilizamos la regresión logística como un método de análisis de sensibilidad par a un modelo de análisis de viabilidad poblacional de perros silvestres Africanos ( Lycaon pictus) y comparamos estos resultados con análisis de sensibilidad convencionales de modelos estocásticos y determinísticos. Coeficientes estandarizados de los análisis de regresión logística indicaron que la supervivencia de cachorros explicaba la mayor variabilidad en la probabilidad de extinción, independientemente de que el modelo incorporara la denso-dependencia. La supervivencia de adultos y la desviación estándar de la supervivencia de cachorros fueron los parámetros que siguieron en importancia en simulaciones de denso-dependencia, mientras que la severidad y la probabilidad de catástrofes fueron más importantes durante simulaciones denso-independientes. La inclusión de la denso dependencia disminuyó la probabilidad de extinción, pero ni la severidad ni la inclusión de denso-dependencia fueron parámetros importantes. Resultados de los análisis de sensibilidad relativa que alteraron cada parámetro en 10% de su rango y análisis de la simulación de etapas de vida de modelos matriciales determinísticos apoyaron los resultados de la regresión logística, indicando que la supervivencia de cachorros y su variación fueron más importantes que otros parámetros. Sin embargo, el análisis de sensibilidad convencional del modelo estocástico que cambiaron cada parámetro en 10% de su valor medio y el análisis de elasticidad indicaron que la supervivencia de adultos fue más importante que la supervivencia de cachorros. Evaluamos las ventajas y desventajas de utilizar la regresión logística para analizar la sensibilidad de modelos estocásticos de viabilidad poblacional y concluimos que es un método poderoso porque puede atender interacciones entre parámetros ingresados e incorporar el rango de variabilidad de parámetros, aunque los coeficientes de regresión estandarizada no son comparables entre estudios. La estructura del modelo, el método de análisis y la incertidumbre en los parámetros afectan las conclusiones del análisis de sensibilidad. Por lo tanto, se debe realizar una rigurosa exploración y análisis del modelo para entender su comportamiento y sus implicaciones en el manejo. [source] Occurrence and prognosis of hand eczema in the car industry: results from the PACO follow-up study (PACO II)CONTACT DERMATITIS, Issue 6 2008Christian J. Apfelbacher Background:, Only a few epidemiological studies on hand eczema (HE) in the metalworking industry have been conducted, and no study has attempted a long-term follow-up. Objectives:, In the Prospective Audi Cohort (PACO) II follow-up study, we aimed to estimate burden and prognosis of HE in a car industry setting (follow-up > 10 years). Patients/Methods:, Eligible participants were individuals who had been examined in the original PACO study (1990,1998) and had been followed through until the end of their apprenticeship (n = 1909). Participants were interviewed and underwent dermatological examination. An exposure assessment was carried out according to a pre-defined algorithm. Results:, The follow-up rate was 78.3% (1494/1909). Mean follow-up time was 13.3 [standard deviation 1.3] years. The period prevalence of HE in the follow-up period was 21.0% [95% confidence interval (CI) 19.0,23.1%], yielding a cumulative incidence of 29.3% (95% CI 26.9,31.6%) in the entire study period. HE persisted after the end of apprenticeship in 40.0% (95% CI 33.3,46.7%) of subjects who had had HE during apprenticeship (n = 205). 18.0% (95% CI 15.9,20.1%) developed HE in the follow-up period (n = 1289). Conclusions:, Around 30% of subjects were affected by HE at least once during the study period. HE persisted in 40% of the participants affected during apprenticeship. [source] Functional map and age-related differences in the human face: nonimmunologic contact urticaria induced by hexyl nicotinateCONTACT DERMATITIS, Issue 1 2006Slaheddine Marrakchi Variation in human skin reactivity to various irritants in association with age and body region has been reported. Hexyl nicotinate (HN), a lipophilic nicotinate ester, was used to induce nonimmunologic contact urticaria in human volunteers of 2 age groups: 10 young subjects [24,34 years, mean ± standard deviation (SD) 29.8 ± 3.9 years] and 10 older volunteers (66,83 years, mean ± SD 73.6 ± 17.4 years); and to define skin function and potential age-related differences in various facial areas. About 5 mM of HN in ethanol was applied to 8 locations on the face, neck, and volar forearm. A laser Doppler flowmeter was used to determine baseline blood flow and to monitor the skin blood flow changes after HN application. In the contralateral areas, stratum corneum turnover was determined using 5% dansyl chloride in petrolatum. In the young group, the perioral area exhibited the strongest reaction to HN. In the older group, the chin was the most sensitive site. In both the groups, the forearm was the least responsive. The older group demonstrated a stronger reaction than the younger group in 3 sites (forehead, cheek, and nasolabial area). Stratum corneum turnover was slower in the nasolabial area and in the forearm in both age groups, whereas the fastest was in the perioral area and the chin in the younger group and in the chin and the forehead in the older group. Compared to the older group, the younger group showed a slower stratum corneum turnover in the nose and the neck. This study demonstrates the regional and the age-related variability of the stratum corneum turnover and the skin reactions to HN. These observations may help explain some aspects of the cutaneous intolerance in skin care of the face. [source] MR determination of glomerular filtration rate in subjects with solitary kidneys in comparison to clinical standards of renal function: feasibility and preliminary report,CONTRAST MEDIA & MOLECULAR IMAGING, Issue 2 2009Richard W. Katzberg Abstract This study was conducted to demonstrate the feasibility of quantifying single kidney glomerular filtration rate (skGFR) by magnetic resonance (MR) by comparison to the clinical estimates of GFR in volunteer subjects with a single kidney. Seven IRB-approved subjects with a solitary kidney, stable serum creatinine (SCr) and a 24,h creatinine clearance (CrCl) volunteered to undergo an MR examination that determined renal extraction fraction (EF) with a breathhold inversion recovery echo planar pulse sequence and renal blood flow with a velocity encoded phase imaging sequence. The product of EF and blood flow determines GFR. These values were compared with the 24,h CrCl, estimated GFR by the modification of diet in renal disease (MDRD) regression analysis and the Cockroft,Gault (CG) determination of CrCl. The mean and standard deviation of differences between the MR GFR, MDRD and CG vs the 24,h CrCl were 12.3,±,35.7, ,8.9,±,18.5 and 1.2,±,19.6, respectively. The Student t -test showed that none of the mean differences were statistically significant between techniques. This clinical investigation shows that MR can be used for skGFR determination in human subjects with comparable values to those derived from clinically used serum-based GFR estimation techniques. Copyright © 2009 John Wiley & Sons, Ltd. [source] Prevalence and correlates of traumatic brain injury among delinquent youthsCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 4 2008Brian E. Perron Background,Delinquent youth frequently exhibit high-risk behaviours that can result in serious injury. However, little is known about traumatic brain injuries (TBIs) and their correlates in this population. Aims,To examine the period prevalence and correlates of TBIs in delinquent youths. Method,Interviews were conducted with 720 (97.3%) residents of 27 Missouri Division of Youth Services rehabilitation facilities between March 1 and May 31, 2003. Participants [mean age (Mage) = 15.5, standard deviation (SD) = 1.2, 87% male] completed measures assessing TBI, substance use, psychiatric symptoms, and antisocial traits/behaviours. TBI was defined as ever having sustained a head injury causing unconsciousness for more than 20 minutes. Results,Nearly one-in-five youths (18.3%) reported a lifetime TBI. Youths with TBIs were significantly more likely than youths without to be male, have received a psychiatric diagnosis, report an earlier onset of criminal behaviour/substance use and more lifetime substance use problems and past-year criminal acts, evidence psychiatric symptoms, report lifetime suicidality, be impulsive, fearless, and external in locus of control and criminally victimized in the year preceding incarceration. Male gender and frequency of own criminal victimization were important predictors of TBI in multivariate analyses. Regression analyses adjusted for demographic factors, indicated that youths with TBIs were at significantly elevated risk for current depressive/anxious symptoms, antisocial behaviour, and substance abuse problems. Conclusions,TBI is common among delinquent youth and associated with wide ranging psychiatric dysfunction; however, the causal role of TBIs in the pathogenesis of co-morbid conditions remains unclear. Copyright © 2008 John Wiley & Sons, Ltd. [source] Specificity of cognitive distortions to antisocial behavioursCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 2 2008Alvaro Q. Barriga Introduction/Background,Cognitive distortions have long been posited to facilitate antisocial behaviours, but the specificity of such distortions has rarely been studied. Aims,To replicate findings of specificity between particular cognitions and externalizing or internalizing behaviours; to test for specificity of relationship between particular cognitions and different types of externalizing behaviours. Methods,The participants were 239 male youths aged 10 to 19 years (mean (M) = 14.22, standard deviation (SD) = 1.64) from schools on the island of Curaçao. Their cognitive distortions and problem behaviours were investigated through self-report. Results,In controlled analyses, self-serving cognitive distortions were associated with externalizing behaviours whereas self-debasing cognitive distortions were associated with internalizing behaviours. Within the externalizing domain, self-serving distortions with overt behavioural referents were linked to aggressive behaviour while self-serving distortions with covert behavioural referents were linked to delinquent behaviour. Within the aggression domain, distortions with opposition-defiance referents related to verbal aggression whereas distortions with physical aggression referents related to physically aggressive behaviour. Conclusions and implications for practice,The degree of cognitive-behavioural specificity documented by this study was remarkable. The observed pattern suggests that cognitive interventions designed for externalizing versus internalizing behaviours should differ in therapeutic approach. Copyright © 2008 John Wiley & Sons, Ltd. [source] Small and Medium-Sized Congenital Nevi in Children: A Comparison of the Costs of Excision and Long-Term Follow-UpDERMATOLOGIC SURGERY, Issue 12 2009FERNANDO ALFAGEME ROLDÁN MD BACKGROUND Clinical decisions on whether to follow up or remove small and medium congenital melanocytic nevi (SMCMN) in children have cost implications that have not been studied. OBJECTIVES To compare the costs of excision of SMCMN in children with lifelong follow-up in a tertiary center. METHODS AND MATERIALS We elaborated models for the evaluation of the costs of excision and long-term follow-up. We retrospectively collected data on 113 consecutive excised SMCMN (105 single-step interventions and 8 multiple-step interventions) from the medical records of our pediatric dermatology unit from 2001 to 2007 and calculated and compared the costs (direct and indirect) of surgery and follow-up. RESULTS The mean ± standard deviation and total cohort costs for single-step interventions were ,1,504.73 ± 198.33 and 157,996.20, respectively. Median and cohort lifelong follow-up costs were similar if performed every 4 years (1,482.66 ± 34.98 and 156,679.63). For multiple-step interventions (3 or 4 steps), surgery costs were similar to those of annual lifelong follow-up. In the case of two-step surgery, costs were similar to lifelong follow-up every 2 years. CONCLUSIONS An analysis of the costs of surgery and long-term follow-up in children with SMCMN is possible. Although the clinical judgment of the dermatologist and parental opinion are the main determinants in the management of SMCMN, costs should also be taken into account. [source] Development of dynamic stability in children's rhythmic movementDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2009Eric G. James Abstract This study examined the hypothesis that the stability of rhythmic motor patterns increases with developmental age in children. Children aged 6 and 10 years and adults (18- to 23-year-olds) rocked back and forth at their preferred amplitude and frequency while seated on a wooden box placed atop a force platform. Participants performed the seated rocking task with their feet supported and unsupported. There was an age-related decrease in rocking frequency and variability of the rocking cycle period, while the stability of the rocking dynamics increased, as indexed by the standard deviation of the phase angle of center of pressure motion. The presence of foot support decreased the stability of the rocking dynamics and reduced cycle period variability in the children, but not the adults. The results revealed that increments of age are associated with an increase in the stability of rhythmic motor patterns even when environmental conditions are altered. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 465,473, 2009 [source] The effect of thiazolidinediones on adiponectin serum level: a meta-analysisDIABETES OBESITY & METABOLISM, Issue 5 2008N. Riera-Guardia Background and aims:, Adiponectin is a hormone mainly produced by white adipose tissue. Decreased levels of adiponectin are linked with visceral obesity, insulin resistance states, and cardiovascular diseases. Recently, several studies have pointed out an increase in adiponectin serum levels in subjects undergoing treatment with thiazolidinediones (TZD). The aim of this study is to systematically review the current state of evidence of the effect of TZD on adiponectin serum level with special attention to avoid publication bias. Materials and methods:, An extensive literature search was performed. Meta Analysis Version 2.0 computer program was used to calculate statistical differences in means and 95% confidence interval (CI). Publication bias was assessed using different statistical approaches. Results:, In the meta-analysis including 19 studies the overall standardized mean difference was 0.94 (95% CI, 0.81,1.06) which means that subjects treated with TZDs on average had means of adiponectin concentration that were about 1 standard deviation higher than the comparison groups even after controlling for possible biases. Conclusions:, The results obtained agree with a moderate increase of serum adiponectin. The results clearly reveal an increase of endogenous serum adiponectin levels by intake of TZDs and may point to a potential new option to manage obesity-related diseases. [source] Prevalence and projections of diabetes and pre-diabetes in adults in Sri Lanka,Sri Lanka Diabetes, Cardiovascular Study (SLDCS)DIABETIC MEDICINE, Issue 9 2008P. Katulanda Abstract Aims To determine the prevalence of diabetes mellitus and pre-diabetes (impaired fasting glucose and impaired glucose tolerance) in adults in Sri Lanka. Projections for the year 2030 and factors associated with diabetes and pre-diabetes are also presented. Methods This cross-sectional study was conducted between 2005 and 2006. A nationally representative sample of 5000 adults aged , 18 years was selected by a multi-stage random cluster sampling technique. Fasting plasma glucose was tested in all participants and a 75-g oral glucose tolerance test was performed in non-diabetic subjects. Prevalence was estimated for those > 20 years of age. Results Response rate was 91% (n = 4532), males 40%, age 46.1 ± 15.1 years (mean ± standard deviation). The age,sex standardized prevalence (95% confidence interval) of diabetes for Sri Lankans aged , 20 years was 10.3% (9.4,11.2%) [males 9.8% (8.4,11.2%), females 10.9% (9.7,12.1%), P = 0.129). Thirty-six per cent (31.9,40.1%) of all diabetic subjects were previously undiagnosed. Diabetes prevalence was higher in the urban population compared with rural [16.4% (13.8,19.0%) vs. 8.7% (7.8,9.6%); P < 0.001]. The prevalence of overall, urban and rural pre-diabetes was 11.5% (10.5,12.5%), 13.6% (11.2,16.0%) and 11.0% (10.0,12.0%), respectively. Overall, 21.8% (20.5,23.1%) had some form of dysglycaemia. The projected diabetes prevalence for the year 2030 is 13.9%. Those with diabetes and pre-diabetes compared with normal glucose tolerance were older, physically inactive, frequently lived in urban areas and had a family history of diabetes. They had higher body mass index, waist circumference, waist,hip ratio, systolic/diastolic blood pressure, low-density lipoprotein cholesterol and triglycerides. Insulin was prescribed to 4.4% (2.7,6.1%) of all diabetic subjects. Conclusions One in five adults in Sri Lanka has either diabetes or pre-diabetes and one-third of those with diabetes are undiagnosed. [source] The cost-effectiveness of continuous subcutaneous insulin infusion compared with multiple daily injections for the management of diabetesDIABETIC MEDICINE, Issue 7 2003P. Scuffham Abstract Aims To estimate the cost effectiveness of continuous subcutaneous insulin infusion (CSII) compared with multiple daily injections (MDI) for patients using insulin pumps. Methods We constructed a Markov model to estimate the costs and outcomes for patients with insulin-dependent diabetes (IDDM) treated with CSII using an insulin pump compared with MDI. Key parameters were obtained from the published scientific literature. The primary outcome was quality-adjusted life years (QALYs). Monte Carlo simulations were undertaken for 10 000 hypothetical patients over 8 years of monthly cycles (the expected life of a pump). Results Over an 8-year period an average patient could expect to gain 0.48 [standard deviation (sd) 0.20] QALYs using CSII compared with MDI. The additional cost over 8 years for this gain was £5462 (sd£897). The incremental cost per QALY was £11 461 (sd£3656). CSII was most cost-effective in patients who had more than two severe hypoglycaemic events per year and who required admission to hospital at least once every year. Cases where CSII might be not economically viable are cases where diabetes is well controlled with few severe hypoglycaemic events. Results were most sensitive to the number of hypoglycaemic events per patient and the utility weights used to estimate QALYs. Conclusion CSII is a worthwhile investment when targeted to those who might benefit most. Diabet. Med. 20, 586,593 (2003) [source] The Impact of a Concurrent Trauma Alert Evaluation on Time to Head Computed Tomography in Patients with Suspected StrokeACADEMIC EMERGENCY MEDICINE, Issue 3 2006Esther H. Chen MD Background: Emergency department (ED) overcrowding threatens quality of care by delaying the time to diagnosis and treatment of patients with time-sensitive diseases, such as acute stroke. Objective: The authors hypothesized that the presence of a trauma alert evaluation would impede the time to head computed tomography (hCT) in patients with stroke-like symptoms. Methods: This was a secondary analysis of prospectively collected data on patients with potential stroke who received an hCT in an urban trauma center ED from January 1, 2004, to November 30, 2004. Structured data collection included historical and examination items, National Institutes of Health (NIH) stroke scale score, laboratory and radiographic results, and final diagnosis. Admitted patients were followed in hospital. Patients who presented within one hour following a trauma evaluation were compared with patients who presented without concurrent trauma for triage time until completion of hCT. Chi-square, t-tests, and 95% confidence intervals (95% CIs) were used for comparisons. Results: The 171 patients enrolled had a mean (± standard deviation) age of 60.7 (± 7) years; 60% were female; and 58% were African American. Of these, 72 patients had a significant cerebrovascular event (38 [22%] ischemic stroke, 25 [15%] transient ischemic attack, seven [4%] intracranial hemorrhage, one [0.6%] subarachnoid hemorrhage, and one [0.6%] subdural hematoma). The remaining diagnoses included 4.6% migraine, 2.3% seizure, 2.9% syncope, 2.3% Bell's palsy, and 2.9% vertigo. There was no significant difference in time to hCT in patients who presented during a trauma activation and those who did not (99 minutes [interquartile range (IQR) = 24,156] vs. 101 minutes [IQR = 43,151.5]; p = 0.537). In subgroup analysis of patients with a significant cerebrovascular event, times to hCT were also similar (24 minutes [IQR = 12,99] vs. 61 minutes [IQR = 15,126]; p = 0.26). Conclusions: In the authors' institution, the presence of concurrent trauma evaluation does not delay CT imaging of patients with potential stroke. [source] The Mental Health of Expatriate and Kosovar Albanian Humanitarian Aid WorkersDISASTERS, Issue 2 2005Barbara Lopes Cardozo The mental health consequences of exposure to traumatic events and the risk factors for psychological morbidity among expatriate and Kosovar Albanian humanitarian aid workers have not been well studied. In June 2000, we used standardised screening tools to survey 285 (69.5%) of 410 expatriate aid workers and 325 (75.8%) of 429 Kosovar Albanian aid workers from 22 humanitarian organizations that were implementing health programmes in Kosovo. The mean number of trauma events experienced by expatriates was 2.8 (standard deviation: 2.7) and by Kosovar staff 3.2 (standard deviation: 2.8). Although only 1.1% of expatriate and 6.2% of Kosovar aid workers reported symptoms consistent with the diagnosis for post-traumatic stress disorder, 17.2% and 16.9%, respectively, reported symptoms satisfying the definition of depression. Regression analysis demonstrated that the number of trauma events experienced was significantly associated with depression for the two sets of workers. Organisational support services may be an important mediating factor and should be targeted at both groups. [source] An improved validated ultra high pressure liquid chromatography method for separation of tacrolimus impurities and its tautomersDRUG TESTING AND ANALYSIS, Issue 3 2010Acharya Subasranjan Abstract A selective, specific and sensitive ultra high pressure liquid chromatography (UHPLC) method was developed for determination of tacrolimus degradation products and tautomers in the preparation of pharmaceuticals. The chromatographic separation was performed on Waters ACQUITY UPLC system and BEH C8 column using gradient elution of mobile phase A (90:10 v/v of 0.1% v/v triflouroacetic acid solution and Acetonitrile) and mobile phase B (90:10 v/v acetonitrile and water) at a flow rate of 0.6 mL min,1. Ultraviolet detection was performed at 210 nm. Tacrolimus, tautomers and impurities were chromatographed with a total run time of 25 min. Calibration showed that the response of impurity was a linear function of concentration over the range 0.3,6 µg mL,1 (r2 , 0.999) and the method was validated over this range for precision, intermediate precision, accuracy, linearity and specificity. For precision study, percentage relative standard deviation of each impurity was < 15% (n = 6). The method was found to be precise, accurate, linear and specific. The proposed method was successfully employed for estimation of tacrolimus impurities in pharmaceutical preparations. Copyright © 2010 John Wiley & Sons, Ltd. [source] Effectiveness of grass strips in trapping suspended sediments from runoffEARTH SURFACE PROCESSES AND LANDFORMS, Issue 9 2010Chengzhong Pan Abstract Little information is available concerning the performance of grass strips for erosion control from steep cropland. An experiment was conducted on 5-m-long grass strips with slopes of 3°,15° that were subjected to silt laden runoff and simulated rainfall, to investigate the sediment trapping processes. The grass strips had three treatments including intact grass control (C), no litter (dead grass material covering the soil surface was removed) (NL), and no litter or leaves (only 2,3,cm grass stems and roots were reserved) (NLL). Generally the grass strips had a high effectiveness in trapping sediment from steep cropland runoff. Sediment trapping efficiency (STE) decreased with increasing slope gradient, and even for a 15° slope, STE was still more than 40%. Most sediment deposited in the backwater region before each grass strips. The removal of grass litter or/and leaves had no significant influence on STE. The sediment median size (D50) in inflow was greater than that in outflow, and the difference (,D50) decreased with increasing slope. A positive power relationship between STE and ,D50 can be obtained. Grass strips were more effective in trapping sediments coarser than 10 or 25,µm, but sediments finer than 1,µm were more readily removed from runoff than particles in the range of 2 to approximately 10,µm. Grass litter had less influence on flow velocity than leaves because the deposited sediment partially covered the litter layer. Mean flow velocity and its standard deviation were negatively correlated with STE, and they can help make good estimation of STE. Results from this study should be useful in planting and managing forage grass to effectively conserve soil loss by runoff from steep slopes on the Loess Plateau of China. Copyright © 2010 John Wiley & Sons, Ltd. [source] Comparison of LiDAR waveform processing methods for very shallow water bathymetry using Raman, near-infrared and green signalsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2010Tristan Allouis Abstract Airborne light detection and ranging (LiDAR) bathymetry appears to be a useful technology for bed topography mapping of non-navigable areas, offering high data density and a high acquisition rate. However, few studies have focused on continental waters, in particular, on very shallow waters (<2,m) where it is difficult to extract the surface and bottom positions that are typically mixed in the green LiDAR signal. This paper proposes two new processing methods for depth extraction based on the use of different LiDAR signals [green, near-infrared (NIR), Raman] of the SHOALS-1000T sensor. They have been tested on a very shallow coastal area (Golfe du Morbihan, France) as an analogy to very shallow rivers. The first method is based on a combination of mathematical and heuristic methods using the green and the NIR LiDAR signals to cross validate the information delivered by each signal. The second method extracts water depths from the Raman signal using statistical methods such as principal components analysis (PCA) and classification and regression tree (CART) analysis. The obtained results are then compared to the reference depths, and the performances of the different methods, as well as their advantages/disadvantages are evaluated. The green/NIR method supplies 42% more points compared to the operator process, with an equivalent mean error (,4·2,cm verusu ,4·5,cm) and a smaller standard deviation (25·3,cm verusu 33·5,cm). The Raman processing method provides very scattered results (standard deviation of 40·3,cm) with the lowest mean error (,3·1,cm) and 40% more points. The minimum detectable depth is also improved by the two presented methods, being around 1,m for the green/NIR approach and 0·5,m for the statistical approach, compared to 1·5,m for the data processed by the operator. Despite its ability to measure other parameters like water temperature, the Raman method needed a large amount of reference data to provide reliable depth measurements, as opposed to the green/NIR method. Copyright © 2010 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||||||||||||||||||||