Growing into a different brain: The outcome of very preterm birth at school age

Oosterlaan, J. [Promotor]Lafeber, H.N. [Promotor]Elburg, R.M. van [Copromotor

Het nieuwe telen : energie onder de knie : komkommer

Vanuit het idee dat energiezuinig telen bereikt kan worden door goede isolatie, beheersing van de luchtvochtigheid en aanpassing van het teeltplan is project Het Nieuwe Telen komkommer uitgevoerd. Als doelstelling is geformuleerd een energieinput voor warmte van gelijk aan 25 m3 aardgas en handhaving van de de productie op 80 kg of wel 200 stuks per m2. Om de haalbaarheid van deze doelstelling te onderzoeken is een afdeling van 1000 m2 uitgerust met drie schermen- één vast folie en twee beweegbare schermen- en een installatie voor geavanceerde ventilatie

One-Loop Dominance in the Imaginary Part of the Polarizability: Application to Blackbody and Non-Contact van der Waals Friction

Phenomenologically important quantum dissipative processes include black-body friction (an atom absorbs counterpropagating blue-shifted photons and spontaneously emits them in all directions, losing kinetic energy) and non-contact van der Waals friction (in the vicinity of a dielectric surface, the mirror charges of the constituent particles inside the surface experience drag, slowing the atom). The theoretical predictions for these processes are modified upon a rigorous quantum electrodynamic (QED) treatment, which shows that the one-loop "correction" yields the dominant contribution to the off-resonant, gauge-invariant, imaginary part of the atom's polarizability at room temperature, for typical atom-surface interactions. The tree-level contribution to the polarizability dominates at high temperature.Comment: 5 pages; RevTe

Theory of Noncontact Friction for Atom-Surface Interactions

The noncontact (van der Waals) friction is an interesting physical effect, which has been the subject of controversial scientific discussion. The direct friction term due to the thermal fluctuations of the electromagnetic field leads to a friction force proportional to 1/Z5 (where Z is the atom-wall distance). The backaction friction term takes into account the feedback of thermal fluctuations of the atomic dipole moment onto the motion of the atom and scales as 1/Z8. We investigate noncontact friction effects for the interactions of hydrogen, ground-state helium, and metastable helium atoms with α-quartz (SiO2), gold (Au), and calcium difluorite (CaF2). We find that the backaction term dominates over the direct term induced by the thermal electromagnetic fluctuations inside the material, over wide distance ranges. The friction coefficients obtained for gold are smaller than those for SiO2 and CaF2 by several orders of magnitude

Analyses of CD27++ Plasma Cells in Peripheral Blood from Patients with Bacterial Infections and Patients with Serum Antinuclear Antibodies

The number of CD27++ plasma cells (PCs) in peripheral blood may be a valuable biomarker for systemic lupus erythematosus (SLE) disease management. More insights into the behavior of the PC population are, however, required to validate CD27 as a reliable biomarker. In the current study, we have monitored the PC compartment of patients with acute bacterial infections and patients with SLE and, in addition, examined the relationship between the presence of serum antinuclear antibodies (ANAs) and the number of peripheral PCs. Kinetic analyses in patients with bacterial infection revealed a 10–60-fold expansion of the CD27++ PC compartment that peaked at day 2–5 and returned toward normal values at day 7–9 after hospital admission. The transient expansion of the PC population appeared to be a late phenomenon in the process of recovering from a bacterial infection. SLE subjects had significantly increased frequencies of PCs compared with patients suspected of a connective tissue disease and healthy controls. In patients suspected of a connective tissue disease, no relationship was found between the presence of serum ANAs and the number of CD27++ PCs. Additionally, the presence of serum ANAs was not associated with abnormalities in other peripheral B-cell subsets. It remains to be established at which stage of SLE development the expansion of the PC compartment is initiated

Interpretation of glucocorticoids in neonatal hair: A reflection of intrauterine glucocorticoid regulation?

Background: Glucocorticoids (GCs) measured in neonatal hair might reflect intrauterine as well as postpartum GC regulation. We aimed to identify factors associated with neonatal hair GC levels in early life, and their correlation with maternal hair GCs. Methods: In a single-center observational study, mother-infant pairs (n = 107) admitted for >72 h at the maternity ward of a general hospital were included. At birth and an outpatient visit (OPV, n = 72, 44 ± 11 days postpartum), maternal and neonatal hair was analyzed for cortisol and cortisone levels by LC-MS/MS. Data were analyzed regarding: (1) neonatal GC levels postpartum and at the OPV, (2) associations of neonatal GC levels with maternal GC levels and (3) with other perinatal factors. Results: (1) Neonatal GC levels were >5 times higher than maternal levels, with a decrease in ±50% between birth and the OPV for cortisol. (2) Maternal and neonatal cortisol, but not cortisone, levels were correlated both at postpartum and at the OPV. (3) Gestational age was associated with neonatal GC postpartum (log-transformed β (95% CI): cortisol 0.07 (0.04-0.10); cortisone 0.04 (0.01-0.06)) and at the OPV (cortisol 0.08 (0.04-0.12); cortisone 0.00 (-0.04 to 0.04)), while weaker associations were found between neonatal GCs and other perinatal and maternal factors. Conclusions: Neonatal hair GCs mainly reflect the third trimester increase in cortisol, which might be caused by the positive feedback loop, a placenta-driven phenomenon, represented by the positive association with GA. Between birth and 1.5 months postpartum, neonatal hair cortisol concentrations decrease sharply, but still appear to reflect both intra- and extrauterine periods

Academic performance of children born preterm : a meta-analysis and meta-regression

Background: Advances in neonatal healthcare have resulted in decreased mortality after preterm birth but have not led to parallel decreases in morbidity. Academic performance provides insight in the outcomes and specific difficulties and needs of preterm children. Objective: To study academic performance in preterm children born in the antenatal steroids and surfactant era and possible moderating effects of perinatal and demographic factors. Design: PubMed, Web of Science and PsycINFO were searched for peer-reviewed articles. Cohort studies with a full-term control group reporting standardised academic performance scores of preterm children (<37 weeks of gestation) at age 5 years or older and born in the antenatal steroids and surfactant era were included. Academic test scores and special educational needs of preterm and full-term children were analysed using random effects meta-analysis. Random effects meta-regressions were performed to explore the predictive role of perinatal and demographic factors for between-study variance in effect sizes. Results: The 17 eligible studies included 2390 preterm children and 1549 controls. Preterm children scored 0.71 SD below full-term peers on arithmetic (p<0.001), 0.44 and 0.52 SD lower on reading and spelling (p<0.001) and were 2.85 times more likely to receive special educational assistance (95% CI 2.12 to 3.84, p<0.001). Bronchopulmonary dysplasia explained 44% of the variance in academic performance (p=0.006). Conclusion: Preterm children born in the antenatal steroids and surfactant era show considerable academic difficulties. Preterm children with bronchopulmonary dysplasia are at particular risk for poor academic outcome