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One Standard Deviation (one + standard_deviation)
Selected AbstractsAir temperature changes in the arctic from 1801 to 1920INTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 6 2010Rajmund Przybylak Abstract In this paper, the results of an investigation into the thermal conditions in the Arctic in the period from 1801 to 1920 are presented. For this ,early instrumental' period limited meteorological data exist. Generally, the first meteorological stations in the Arctic were established in the second half of the 19th century and almost all of them were located in the coastal parts of Greenland. In order to get at least a rough idea of thermal conditions in the Arctic in the study period, data from different land and marine expeditions were collected. A total of 118 temperature series of monthly means have been gathered. Although the area and time periods covered by the data are variable, it is still possible to describe the general character of the temperature conditions. The results show that the areally averaged Arctic temperature in the early instrumental period was 0.8 °C lower than the next 60-year period (1861,1920). In comparison to present-day conditions, winter and autumn were significantly colder (winter by 1.6 °C and autumn by 0.9 °C) than were summer (colder by 0.4 °C) and spring (colder by only 0.2 °C). The air temperature in the real Arctic during the first International Polar Year (IPY) was, on average, colder than today by 1.0,1.5 °C. Winter was exceptionally cold with the average temperature being lower by more than 3 °C in all months except February. On the other hand, spring (March,May) was slightly warmer than today, and April was exceptionally warm (1.1 °C above present norm). The temperature differences calculated between historical and modern mean monthly temperatures show that majority of them lie within one standard deviation (SD) from present long-term mean. Thus, it means that the climate in the early instrumental period was not as cold as some proxy data suggest. Copyright © 2009 Royal Meteorological Society [source] Southern hemisphere cyclones and anticyclones: recent trends and links with decadal variability in the Pacific OceanINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 11 2007Dr Alexandre Bernardes Pezza Abstract The aim of this paper is to study the association between the extratropical Southern Hemisphere and the decadal variability in the Pacific Ocean (PO). We discuss a pattern of coherent large-scale anomalies and trends in cyclone and anticyclone behaviour in light of the climate variability in the PO over the ERA40 reanalysis period (1957,2002). The two representative PO indices are the Pacific Decadal and Interdecadal Oscillations (PDO and IPO), and here the PDO is chosen owing to it being less associated with the southern oscillation index (SOI). Composites of the indicators of the density and intensity of cyclones/anticyclones given by an automatic tracking scheme were calculated for the years when the PDOI was more than one standard deviation above or below its mean. Although the ERA40 is not free from noise and assimilation changes, the results show a large-scale feature, which seems to be robust and agrees with earlier studies using different data sets. The sea-level pressure shows a strong annular structure related to the PDO, which is not seen for the SOI, with lower pressure around Antarctica during the positive phase and vice versa. More intense (and fewer) cyclones and anticyclones were observed during the positive PDO. This is less consistent for the SOI, particularly during the summer when a different PDO/SOI pattern arises at high latitudes. The trends project a pattern coincident with the positive PDO phase and seem to be linked with the main climate shift in the late seventies. Trends observed over the Tasman Sea are consistent with declining winter rainfall over southeastern Australia. Most patterns are statistically significant and seem robust, but random changes in ENSO may play a part, to a certain degree, in modulating the results, and a physical mechanism of causality has not been demonstrated. Although global warming and related changes in the Southern Annular Mode (SAM) may also help explain the observed behaviour, the large-scale response presented here provides a new insight and would be of considerable interest for further modelling studies. Copyright © 2007 Royal Meteorological Society [source] Postnatal corticosteroids and sensorineural outcome at 5 years of ageJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 3 2000The Victorian Infant Collaborative Study Group Background: Postnatal corticosteroids reduce ventilator dependence in preterm infants, but possible long-term benefits for either survival or sensorineural morbidity are not proved. Aim: The aim of this study was to determine the association between corticosteroid therapy given postnatally and sensorineural outcome in childhood. Subjects: The subjects comprised 346 consecutive livebirths either of birthweight < 1000 g or with gestational age < 28 weeks born in the state of Victoria during 1991 and 1992, and who survived the first week after birth; 120 (34.7%) were given corticosteroids postnatally. Results: Of the 120 children who received corticosteroids, 98 (81.7%) survived to 5 years of age, compared with 200 (88.5%) of the 226 children who did not receive corticosteroids. At 5 years of age, survivors treated with corticosteroids postnatally had significantly higher rates of cerebral palsy (corticosteroids 23%, no corticosteroids 4%), blindness (corticosteroids 4%, no corticosteroids 1%) or an intelligence quotient more than one standard deviation below the mean (corticosteroids 54%, no corticosteroids 32%) compared with children not treated with corticosteroids. The rate of sensorineural disabilities imposed by these impairments was significantly higher in children treated with postnatal corticosteroids, and the association between adverse sensorineural outcome and postnatal corticosteroids remained after adjustments for potentially confounding variables. In a separate case-control analysis of 60 children in each group, the rate of cerebral palsy remained significantly elevated (corticosteroids 22%, no corticosteroids 5%). Conclusion: Postnatal corticosteroid therapy is associated with substantial adverse sensorineural outcomes at 5 years of age. [source] The impact of climate variability on soybean yields in Argentina.METEOROLOGICAL APPLICATIONS, Issue 1 2007Multivariate regression Abstract Climate variability is examined and discussed in this work, emphasizing its influence over the fluctuation of soybean yield in the Pampas (central-eastern Argentina). Monthly data of rainfall, maximum and minimum temperatures, thermal range and seasonal rainfall were analysed jointly with the soybean yield in the period 1973-2000. Low-frequency variability was significant only in the minimum temperature during November in almost all the stations. This situation is favourable to the crop since during this month, seed germination, a growth stage sensitive to low temperatures, takes place. In the crop's core production region, 72% of the series of soybean yield presented a positive trend. Except in years with extreme rainfall situations, interannual variability of the soybean yield is in phase with the seasonal rainfall interannual variability. During these years, losses in the soybean crop occurred, with yield negative anomalies greater than one standard deviation. Soybean yield showed spatial coherence at the local scale, except in the crop's core zone. The association between each climate variable and yield did not show a defined regional pattern. Summer high temperature and rainfall excesses during the period of maturity and harvest have the greatest negative impact on the crop, whilst higher minimum temperatures during the growing season favour high yields. The joint effect of climate variables over yield was studied with multivariate statistical models, assuming that the effect of other factors (such as soil, technology, pests) is contained in the residuals. The regression models represent the estimates of the yield satisfactorily (high percentage of explained variance) and can be used to assess expected anomalies of mean soybean yield for a particular year. However, the predictor variables of the yield depend on the region. Copyright © 2007 Royal Meteorological Society [source] The effect of psychological motivation on volumes voided during uroflowmetry in healthy aged male volunteersNEUROUROLOGY AND URODYNAMICS, Issue 1 2006Yat-Ching Tong Abstract Aims To study the effect of psychological motivation on the voided volume during uroflowmetry in aged-male volunteers. Methods An open contest of free-flow rate was held for the elderly community. People over 60 years old with no prior history of lower urinary tract symptoms were invited to compete. Participants were given the suggestion to void only when strong desire was experienced because greater the volume, faster the flow. One month later, 20 of the male participants were asked to come back for an office uroflowmetry, given the instruction to hold until strong desire was experienced. The results of the maximum flow rate, mean flow rate, and voided volume were compared between these two tests. Results In the first uroflowmetry, the average voided volume for the 20 participants was 532,±,109 ml; maximum flow rate and average flow rate were 27.1,±,9.4, and 17.2,±,6.4 ml/sec, respectively. The voided volume decreased significantly in the second uroflowmetry (338,±,82 ml, P,<,0.01); the maximum and average flow rates did not changed significantly (24.2,±,9.5 and 14.9,±,6.9 ml/sec, respectively). No participant had a shift of more than one standard deviation between the two tests on the Siroky's flow-rate nomogram. Conclusions With psychological motivation to win the contest, the participants showed greater tolerance to bladder filling. This suggests that the state of mind can affect the perception on bladder sensation. On the other, the performance on emptying function is not significantly improved by motivation. Neurourol. Urdynam. © 2005 Wiley-Liss, Inc. [source] Concurrent validity of the Slosson full-range intelligence test: Comparison with the Wechsler intelligence scale for children,third edition and the Woodcock Johnson tests of achievement,revisedPSYCHOLOGY IN THE SCHOOLS, Issue 1 2002Nancy L. Bell This study examined the concurrent validity of the Slosson Full-Range Intelligence Test (S-FRIT) by comparing S-FRIT scores to the scores of the Wechsler Intelligence Scale for Children,Third Edition (WISC-III) and the Woodcock-Johnson Tests of Achievement,Revised (WJ-R). Data from 123 elementary students' screening and psychological testing results were examined. Results revealed that the S-FRIT scores were more related to overall intelligence, verbal, and math abilities than nonverbal intelligence, reading, or written language abilities. Further, it was found that 89% of the participants' S-FRIT Full-Range IQ scores fell within one standard deviation of their WISC-III FSIQ scores, with an average discrepancy of 7.6 points. Discrepancies between S-FRIT and WISC-III scores were also examined by educational diagnostic categories and ability levels. Limitations and suggestions for future research are provided. © 2002 John Wiley & Sons, Inc. [source] High-risk colorectal adenomas and serum insulin-like growth factorsBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 1 2001A. G. Renehan Background: This study investigated the hypothesis that circulating levels of insulin-like growth factor (IGF) I and its main binding protein (IGFBP-3) predict for the presence of colorectal adenomas, surrogate markers of colorectal cancer risk. Methods: Within the Flexi-Scope Trial (healthy volunteers aged 55,64 years), at one study centre, IGF-I and IGFBP-3 levels in serum samples collected prospectively from 442 attendants were measured. Of these, 100 individuals underwent a complete screening colonoscopy. There were 47 normal examinations, while in 11 examinations low-risk adenomas and in 42 examinations high-risk adenomas were identified. Estimates of relative risk (RR) for the adenomatous stages were calculated by means of unconditional logistic regression, adjusting for known risk factors. Results: Mean serum IGF-I and IGFBP-3 levels were similar in individuals with a normal colonoscopy finding and in those with low-risk adenomas. By contrast, the mean(s.d.) serum IGF-I level was increased (190(53) versus 169(54) µg/l; P = 0·06) and the serum IGFBP-3 concentration was significantly decreased (3·22(0·60) versus 3·47(0·62) mg/l; P = 0·05) in individuals with high-risk adenomas compared with levels in those with normal colonoscopy and low-risk adenomas combined. Levels were unaffected by removal of the adenomas. With high-risk adenoma as the dependent factor, regression models demonstrated a significant positive association with IGF-I after controlling for IGFBP-3 (RR per one standard deviation (1s.d.) change 4·39 (95 per cent confidence interval (c.i.) 1·31,14·7); P = 0·02) and, independently, an inverse association with IGFBP-3 after adjustment for IGF-I (RR per 1s.d. change 0·41 (95 per cent c.i. 0·20,0·82); P = 0·01). Conclusion: These findings suggest that circulating IGF-I and IGFBP-3 levels are related to future colorectal cancer risk and, specifically, may predict adenoma progression. © 2001 British Journal of Surgery Society Ltd [source] | |||||||||||||