2,905 research outputs found
Threshold Perspectives on Meson Production
Studies of meson production in nucleon-nucleon collisions at threshold are
characterised by few degrees of freedom in a configuration of well defined
initial and final states with a transition governed by short range dynamics.
Effects from low-energy scattering in the exit channel are inherent to the data
and probe the interaction in baryon-meson and meson-meson systems otherwise
difficult to access.
From dedicated experiments at the present generation of cooler rings precise
data are becoming available on differential and eventually spin observables
allowing detailed comparisons between complementary final states. To discuss
physics implications of generic and specific properties, recent experimental
results on meson production in proton-proton scattering obtained at CELSIUS and
COSY serve as a guideline.Comment: 10 pages, 4 figures, Plenary talk at X. International Conference On
Hadron Spectroscopy (Hadron 2003), Aschaffenburg, Germany, 31 Aug - 6 Sep
2003, to be published in AIP Conference Proceeding
Motor and executive function at 6 years of age after extremely preterm birth
BACKGROUND. Studies of very preterm infants have demonstrated impairments in multiple neurocognitive domains. We hypothesized that neuromotor and executive-
function deficits may independently contribute to school failure.
METHODS.We studied children who were born at 25 completed weeks’ gestation in the United Kingdom and Ireland in 1995 at early school age. Children underwent
standardized cognitive and neuromotor assessments, including the Kaufman Assessment Battery for Children and NEPSY, and a teacher-based assessment of academic achievement.
RESULTS. Of 308 surviving children, 241 (78%) were assessed at a median age of 6 years 4 months. Compared with 160 term classmates, 180 extremely preterm children without cerebral palsy and attending mainstream school performed less
well on 3 simple motor tasks: posting coins, heel walking, and 1-leg standing. They more frequently had non–right-hand preferences (28% vs 10%) and more associated/
overflow movements during motor tasks. Standardized scores for visuospatial and sensorimotor function performance differed from classmates by 1.6 and 1.1 SDs of the classmates’ scores, respectively. These differences attenuated but remained significant after controlling for overall cognitive scores. Cognitive, visuospatial
scores, and motor scores explained 54% of the variance in teachers’ ratings of performance in the whole set; in the extremely preterm group, additional variance was explained by attention-executive tasks and gender.
CONCLUSIONS. Impairment of motor, visuospatial, and sensorimotor function, including planning, self-regulation, inhibition, and motor persistence, contributes excess
morbidity over cognitive impairment in extremely preterm children and contributes independently to poor classroom performance at 6 years of age
The EPICure study : growth and blood pressure at 6 years of age following extremely preterm birth
Background: Preterm children are at risk for reduced growth in early childhood, which may predispose them to later changes in blood pressure. We studied growth and blood pressure (BP) in extremely preterm (EP) children at age 6 years.
Methods: We evaluated children who were born at 25 completed weeks of gestation or less in the United Kingdom and Ireland in 1995 when they reached early school age. Children underwent standardized assessments, including auxology and sitting blood pressure.
Results: Of 308 surviving children, 241 (78 percent) were assessed at a median age of 6 years 4 months; 160 full term classmates acted as a comparison group. Compared to classmates, EP children were 1.2 standard deviations (SD) lighter, 0.97SD shorter, BMI was 0.95SD lower and head circumference 1.3SD lower. Compared to 2.5 years of age, EP children showed catch up in terms of weight by 0.37SD, height by 0.42SD and head circumference by 0.13SD. Systolic
and diastolic BP were lower by 2.3mmHg and 2.4mmHg respectively in EP children but these differences were accounted for by differences in height and BMI. Maternal smoking in pregnancy was associated with lower BP, children born before 24 weeks had higher systolic and children given postnatal steroids higher diastolic pressures.
Conclusions: Poor postnatal growth seen after birth and at in the third year persists into school age. Catch up growth reduces some of the early deficit but is least for head growth.
Despite serious postnatal growth restriction blood pressure appears similar in both EP and term classmates
Some Catching Up to Do
The analysis begins with a discussion of the purposes behind the WPPT and the international recognition of a general sound recording performance right. Part I discusses Congress\u27 partial implementation of the WPPT through the Digital Millennium Copyright Act of 1998 (DMCA) and the digital performance right. Part II explores the value that recognition of the full public performance right under the WPPT would create for the American music industry. Finally, Part III proposes a solution in the form of an amendment to the Copyright Act and the coordination of national and international performance rights organizations
Screening for autism in preterm children : diagnostic utility of the Social Communication Questionnaire
Objective Preterm survivors are at high risk for autism
spectrum disorders (ASD). The diagnostic utility of the
Social Communication Questionnaire (SCQ) in screening
for ASD was assessed in extremely preterm children at
11 years of age.
Design All babies born at <26 weeks gestation
in UK and Ireland from March through December
1995 were recruited to the EPICure Study. Of 307
survivors, 219 (71%) were assessed at 11 years.
Parents of 173 children completed the SCQ to screen
for autistic features and the Development and Well
Being Assessment (DAWBA) psychiatric interview.
A consensus diagnosis of ASD was assigned by two
child psychiatrists following review of the DAWBA
parental interview and corresponding DAWBA teacher
questionnaire.
Setting Community-based follow-up.
Results Using the established SCQ cut-off (scores
≥15), 28 (16%) extremely preterm children screened
positive for ASD. Eleven (6%) were assigned a
diagnosis of ASD. Using this cut-off, the SCQ had 82%
sensitivity and 88% specifi city for identifying ASD in this
population. Using a receiver operating characteristic
curve, SCQ scores ≥14 had optimal diagnostic utility
(area under curve: 0.94; sensitivity: 91%; specifi city:
86%). Positive predictive value was relatively low
(31%) resulting in numerous over-referrals. However,
children with false positive screens had signifi cantly
worse neuro-developmental, cognitive and behavioural
outcomes than those with true negative screens.
Conclusion The SCQ has good diagnostic utility for
identifying ASD in extremely preterm children and
is a useful screening tool in this population. Children
with false positive screens represent a high-risk group
in whom further diagnostic assessment would be
benefi cial
Academic attainment and special educational needs in extremely preterm children at 11 years of age : the EPICure Study
Aim: To assess academic attainment and special educational needs (SEN) in extremely preterm (EP) children in middle childhood.
Methods: Of 307 EP (=25 weeks) survivors born in the UK and Ireland in 1995, 219 (71%) were re-assessed at 11 years, with a comparison group of 153 classmates born at term, using standardised tests of cognitive ability and academic attainment and teacher reports of school performance and special educational needs (SEN). Multiple imputation was used to correct for selective dropout.
Results: EP children had significantly lower scores than classmates for cognitive ability (-20 points; 95%CI: -23,-17), reading (-18 points; -22,-15) and mathematics (-27 points; -31,-23). Twenty-nine (13%) EP children attended special school. In mainstream schools, 105 (57%) EP children had SEN (OR: 10; 6, 18) and 103 (55%) required SEN resource provision (OR: 10; 5, 18). Teachers rated 50% of EP children with attainment below the average range compared with 5% of classmates (OR: 18; CI: 8, 41). EP children who are entered for mainstream education an academic year early due to preterm birth had similar academic attainment but required more SEN support (OR: 2; 1.1,3.8).
Conclusions: EP survivors remain at high risk for learning impairments and poor academic attainment in middle childhood. A significant proportion require full-time specialist education and over half of those attending mainstream schools require additional health or educational resources in order to access the national curriculum. The prevalence and impact of SEN is likely to increase as these children approach the transition to secondary school.
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Pathways between childhood victimization and psychosis-like symptoms in the ALSPAC Birth Cohort
Background: Several large population-based studies have demonstrated associations between adverse childhood experiences and later development of psychotic symptoms. However, little attention has been paid to the mechanisms involved in this pathway and the few existing studies have relied on cross-sectional assessments. Methods: Prospective data on 6692 children from the UK Avon Longitudinal Study of Parents and Children (ALSPAC) were used to address this issue. Mothers reported on children’s exposure to harsh parenting and domestic violence in early childhood, and children self-reported on bullying victimization prior to 8.5 years. Presence of children’s anxiety at 10 years and their depressive symptoms at 9 and 11 years were ascertained from mothers, and children completed assessments of self-esteem and locus of control at 8.5 years. Children were interviewed regarding psychotic symptoms at a mean age of 12.9 years. Multiple mediation analysis was performed to examine direct and indirect effects of each childhood adversity on psychotic symptoms. Results: The association between harsh parenting and psychotic symptoms was fully mediated by anxiety, depressive symptoms, external locus of control, and low self-esteem. Bullying victimization and exposure to domestic violence had their associations with psychotic symptoms partially mediated by anxiety, depression, locus of control, and self-esteem. Similar results were obtained following adjustment for a range of confounders and when analyses were conducted for boys and girls separately. Conclusions: These findings tentatively suggest that specific cognitive and affective difficulties in childhood could be targeted to minimize the likelihood of adolescents exposed to early trauma from developing psychotic symptoms
Origins and predictors of friendships in 6- to 8-year-old children born at neonatal risk
Objective
To test effects of gestational age (GA), early social experiences, and child characteristics on children's friendships and perceived peer acceptance.
Study design
As part of the prospective Bavarian Longitudinal Study (1147 children, 25-41 weeks GA), children's friendships (eg, number of friends, frequency of meeting friends) and perceived peer acceptance were assessed before school entry (6 years of age) and in second grade (8 years of age) using child and parent reports. The parent–infant relationship was evaluated during the 5 months after birth. Child characteristics (ie, height, motor impairment, cognitive ability, behavioral problems) were measured at 6 years of age. Multiple regressions estimated effects of GA, parent–infant relationship, and child characteristics.
Results
Overall, children with higher GA had more friends, spent more time with friends, and were more accepted by peers at 6 years of age. Better parent–infant relationships, higher cognitive abilities, and fewer motor and behavioral problems predicted more friendships and higher peer acceptance after adjusting for sex, socioeconomic status, multiples, siblings, and special schooling. Across all GA groups, number of friends (child report: mean change, 1.77; 95% CI, 1.57-1.96) and peer acceptance (child report: mean change, 0.14; 95% CI, 0.09-0.19; parent report: mean change, 0.14; 95% CI, 0.11-0.17) increased with age, but the increase in number of friends was higher among preterm children (ie, interaction effect age*GA group: P = .034).
Conclusions
Our results provide evidence of a dose–response effect of low GA on children's friendships and perceived peer acceptance. Improvements in early parenting and motor, cognitive, and behavioral development may facilitate friendships and peer acceptance for all children across the gestation spectrum
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