13 research outputs found

    An Observational Overview of Solar Flares

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    We present an overview of solar flares and associated phenomena, drawing upon a wide range of observational data primarily from the RHESSI era. Following an introductory discussion and overview of the status of observational capabilities, the article is split into topical sections which deal with different areas of flare phenomena (footpoints and ribbons, coronal sources, relationship to coronal mass ejections) and their interconnections. We also discuss flare soft X-ray spectroscopy and the energetics of the process. The emphasis is to describe the observations from multiple points of view, while bearing in mind the models that link them to each other and to theory. The present theoretical and observational understanding of solar flares is far from complete, so we conclude with a brief discussion of models, and a list of missing but important observations.Comment: This is an article for a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011

    Maternal obesity and development of the preterm newborn at 2 year

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    Aim To evaluate to what extent extremely preterm children (<28 weeks' gestational age) of overweight (BMI 25-29) or obese (BMI ≥30) women are at increased risk of adverse development at 2 years measured with the Bayley Scales of Infant Development II in a multicenter prospective cohort study. Methods Heights and prepregnancy weights of the mothers of 852 preterm born children were collected and included in multinomial logistic regression models. Results Compared to newborns born to mothers with normal BMIs, newborns of obese mothers, but not those of overweight mothers, were more likely to have Bayley Scales indices more than 3 standard deviations below the reference mean (mental: OR = 2.1; 95% CI: 1.3, 3.5) (motor: OR = 1.7; 95% CI: 1.1, 2.7). These associations were even more prominent in children who did not have the intermittent or sustained systemic inflammation profile previously shown to be associated with severely impaired development (mental: OR = 4.6; 95% CI: 1.6, 14) (motor: OR = 3.7; 95% CI: 1.5, 8.9). Conclusion Maternal obesity is associated with an increased risk of impaired offspring development. Some of this impaired development cannot be attributed to confounding due to immaturity, socio-economic correlates or neonatal systemic inflammation

    Is maternal obesity associated with sustained inflammation in extremely low gestational age newborns?

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    Background: The offspring of obese women are at increased risk for systemic inflammation. Blood concentrations of inflammatory proteins in preterm newborns of obese women have not been reported. Aim: To compare blood concentrations in the highest quartile for gestational age of inflammatory proteins and day of blood specimen collection on two days at least one week apart of newborns of overweight (i.e., BMI 25-29) and obese women (i.e., BMI. ≥. 30) with newborns of women with lower BMIs. Because deliveries for spontaneous indications are more likely than those for other indications to be associated with inflammation, we evaluated spontaneous indication deliveries separately from maternal or fetal indications. Study design: Prospective cohort study. Subjects and outcome measures: We measured from 939 children born before the 28th week of gestation 25 inflammation-related proteins in blood obtained on postnatal day 1 (range 1-3), day 7 (range 5-8) and day 14 (range 12-15). Results: Among infants delivered for spontaneous indications, maternal BMI was not related to elevated concentrations of any protein. Among infants delivered for maternal (i.e., preeclampsia) or fetal indications, those whose mother was overweight or obese were more likely than others to have elevated concentrations of inflammation proteins. Conclusions: Maternal pre-pregnancy overweight and obesity appear to contribute to a pro-inflammatory state in very preterm newborns delivered for maternal or fetal indications. Our failure to see a similar pattern among newborns delivered for spontaneous indications, which often have inflammatory characteristics, might reflect competing risks. © 2013 Elsevier Ltd

    Performance measurement: a historical perspective

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    Performance measurement is a topic of current interest at both national and local level. This article is a selective historical review of performance measurement from the 1960s to the present day. Despite the plethora of literature on the topic there appears to be a notable lack of progress. Some of the major and most recent work is assessed and the fundamental difficulties in attempting to measure the performance of library services are noted. It is suggested that future work must concentrate on output measures which are both appropriate to the service being provided and easy to understand by all
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