27 research outputs found
Body size modifies the relationship between maternal serum 25-hydroxyvitamin D concentrations and gestational diabetes in high-risk women
Obesity increases the risk of low 25-hydroxyvitamin D (25(OH) D) concentrations and gestational diabetes (GDM). We explored whether the association between GDM and change in 25(OH) D concentrations measured in the first (7-18 wk) and second (20-27 wk) trimesters of pregnancy is dependent on maternal BMI. The study was a prospective study of 219 women with BMI of >= 30 kg/m2, a history of GDM, or both. The participants were stratified by first-trimester BMI: BMI of = 35 kg/m(2). In the BMI group >= 35 kg/m(2), those who did not develop GDM during the follow-up showed higher increase in serum 25(OH) D concentrations compared with women who developed GDM (43.2 vs. 11.5%; P <0.001). No associations between 25(OH) D concentrations and GDM were observed in other BMI groups. These findings give an important aspect of the role of maternal body size in the association between vitamin D and GDM in high-risk women.Peer reviewe
From implementation to operation and the first measurements with the ELIGANT detectors from ELI-NP
The ELIGANT set of instruments is a dedicated tool being developed
at ELI-NP for studying high-energy collective nuclear excitations using
gamma beams. The topics of interest in these studies range from
fundamental nuclear structure properties of the Giant Dipole Resonance
and the low-energy strength enhancement in the Pygmy Dipole Resonance
region, to applications in p-process nucleosynthesis and propagation of
Ultra-High Energy Cosmic Rays. The equipment consists of large-volume
LaBr3:Ce and CeBr3 detectors for high-energy gamma-rays, liquid
scintillators and lithium glass scintillators for high-and low-energy
neutron time-of-flight, and a proportional counter system of 3He tubes
for cross-section measurements. These instruments have been installed
and commissioned with sources and via in beam measurements, in different
configurations, at the IFIN-HH Tandem/Tandetron accelerators with
terminal voltages of 3 MV and 9 MV. This contribution gives an overview
of the present and future activities with ELIGANT
An in vitro experimental evaluation of the displacement field in an intracranial aneurysm model
The purpose of this paper is to develop a system able to study experimentally the displace-ment field of an in vitro intracranial aneurysm. Origin and growth of aneurysms is the result of a complex interaction between biological processes in the arterial wall and the involved hemo-dynamic phenomena’s. Once the aneurysm forms, the repetitive pressure and shear stresses exerted by the blood flow on the debilitated arterial wall can cause a gradual expansion. One promising method to evaluate and measure this expansion is to use optical field experimental techniques, such as interferometry. In this work the Electronic Speckle Pattern Interferometry was used to evaluate the deformation occurred on an intracranial aneurysm model fabricated in polydimensiloxane (PDMS) by using a 3D printer combined with a soft lithography tech-nique.info:eu-repo/semantics/publishedVersio
Impact of
We have performed the measurement of the 27Al(α, n) cross section at IFIN-HH for a range of energies from 2.5 to 5.2 MeV, using an array of 28 3He counters arranged in 3 concentric rings (ELIGANT-TN). Here we present the experimental setup and discuss the role of the 13C contamination which effects the measurements in the low-energy region. Energy-dispersive X-ray spectroscopy carried out before and after the experiment suggested an increase in the 13C concentration during the experiment
Experimental validation of numerical simulations on a cerebral aneurysm phantom model
The treatment of cerebral aneurysms, found in roughly 5% of the population and associated in case of rupture to a high mortality rate, is a major challenge for neurosurgery and neuroradiology due to the complexity of the intervention and to the resulting, high hazard ratio. Improvements are possible but require a better understanding of the associated, unsteady blood flow patterns in complex 3D geometries. It would be very useful to carry out such studies using suitable numerical models, if it is proven that they reproduce accurately enough the real conditions. This validation step is classically based on comparisons with measured data. Since in vivo measurements are extremely difficult and therefore of limited accuracy, complementary model-based investigations considering realistic configurations are essential. In the present study, simulations based on computational fluid dynamics (CFD) have been compared with in situ, laser-Doppler velocimetry (LDV) measurements in the phantom model of a cerebral aneurysm. The employed 1:1 model is made from transparent silicone. A liquid mixture composed of water, glycerin, xanthan gum and sodium chloride has been specifically adapted for the present investigation. It shows physical flow properties similar to real blood and leads to a refraction index perfectly matched to that of the silicone model, allowing accurate optical measurements of the flow velocity. For both experiments and simulations, complex pulsatile flow waveforms and flow rates were accounted for. This finally allows a direct, quantitative comparison between measurements and simulations. In this manner, the accuracy of the employed computational model can be checked
