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Objectives: To assess the accuracy of transcutaneous bilirubin (TcB) measurements at 5 different body sites in Japanese very low birthweight (VLBW) infants and to determine a cut-off value of TcB to detect total serum/plasma bilirubin (TB) levels ≥10 mg/dL (171 μM).Study Design: In a prospective multicenter study, 85 Japanese VLBW infants were enrolled from 5 neonatal intensive care units during the study period. A total of 383 blood samples from infants not receiving phototherapy or ≥24 hours postphototherapy were analyzed. TcB was measured at the forehead, sternum, upper back, lower abdomen, and waist within 1 hour of blood collection. Linear regression analysis and Bland-Altman plots were used to compare TcB values at each site with TB levels. The TcB cut-off value for detecting TB ≥10 mg/dL was determined by receiver operating characteristics curve analysis.Results: TcB significantly correlated with TB, but the coefficient of determination varied among the sites (forehead: 0.5294, sternum: 0.6488, upper back: 0.6321, lower abdomen: 0.5430, waist: 0.7396). At a TcB value ≥8, the sensitivity was 100% at the sternum and upper back, 85% at the waist, 84% at the forehead, and 64% at the lower abdomen to detect TB ≥10 mg/dL.Conclusions: In Japanese VLBW infants, the accuracy of TcB measurements varies according to body site. TcB ≥8 on the sternum or upper back is more reliable than that on the forehead, lower abdomen, or waist to detect TB levels ≥10 mg/dL. [ABSTRACT FROM AUTHOR]

Objective Asymmetric ventriculomegaly is often evident on brain magnetic resonance imaging (MRI) in very low birth weight infants (VLBWI) and is interpreted as white matter injury. However, no evaluation index for asymmetric left-right and anterior-posterior ventricular sizes has been established. Methods In this retrospective multicenter cohort study, brain T2-weighted MRI was performed at term-equivalent ages in 294 VLBWI born between 2009 and 2011. The value of a lateral ventricular index (LVI) to evaluate asymmetric ventricular size, as well as the relationship between the LVI value and walking at a corrected age of 18 months was investigated. At the level of the foramen of Monro in a horizontal slice, asymmetry between the left and right sides and between the anterior and posterior horns was identified by the corrected width and was detected by a low concordance rate and κ statistic value. An LVI representing the sum of the widths of the four horns of the lateral ventricle corrected for cerebral diameter was devised. Results Asymmetric left-right and anterior-posterior ventricular sizes were confirmed. The LVI value was significantly higher in the non-walking VLBWI group (n = 39) than in the walking VLBWI group (n = 255; 18.2 vs. 15.8, p = 0.02). An LVI cut-off value of 21.5 was associated with non-walking. Multivariate analysis revealed that an LVI value >21.5 was an independent predictor of walking disability at the corrected age of 18 months (odds ratio 2.56, p = 0.008). Conclusions The LVI value calculated via MRI may predict walking disability at a corrected age of 18 months in VLBWI. [ABSTRACT FROM AUTHOR]

Highlights: [•] The density of liquid Fe-3.5wt% C was measured up to 6.8GPa and 2200K. [•] The Fe–C density abruptly increases at pressures between 4.3 and 5.5GPa. [•] The effect of carbon on the density of liquid Fe shows a nonideal mixing behavior. [Copyright &y& Elsevier]

We investigated the hydrogenation of a binary TiFe alloy at 5 GPa and 600 °C by in situ synchrotron radiation X-ray diffraction measurements. After formation of a solid solution of hydrogen in TiFe, an order–disorder phase transition in the metal lattice of TiFe occurred, which yielded a BCC TiFe hydride. The unit cell volume of the BCC hydride increased by 21.0% after the hydrogenation reaction. The volume expansion was larger than that of a γ -hydride TiFeH 1.9 prepared by hydrogenation near ambient conditions. [ABSTRACT FROM AUTHOR]

Abstract: We determined the phase diagram and the equation of state (EoS) of TiH2 at high pressures up to 8.7GPa and high temperatures up to 600°C by in situ synchrotron radiation X-ray diffraction measurements. Compression induced strain inhibited the phase transition from the low-temperature bct phase to the high-temperature fcc phase, making the phase diagram difficult to determine. However, heating around 600°C relieved the strain, and the phase boundary between the bct and fcc phases was elucidated. The phase transition temperature at ambient pressure increased from around room temperature to 200°C at 8.7GPa. The high temperature Birch–Murnaghan EoS was determined for the fcc phase. With the pressure derivative of the bulk modulus K′0 =4.0, the following parameters were obtained: ambient bulk modulus K 0 =97.7±0.2GPa, ambient unit cell of the fcc phase V 0 =88.57±0.02Å3, temperature derivative of the bulk modulus at constant pressure (∂K/∂T) P =−0.01±0.02, and volumetric thermal expansivity α = a + bT with a =2.62±1.4×10−5 and b =5.5±4.5×10−8. K 0 of fcc TiH2 was close to those for pure Ti and bct TiH2 reported in previous studies. [Copyright &y& Elsevier]

Abstract: Diffraction data from hexagonal boron nitride compiled through in situ synchrotron x-ray measurements under pressures and temperatures up to about 8 GPa and 1000 K, respectively, were analyzed in the light of Birch–Murnaghan’s and Parsafar–Mason’s equations of state. The isothermal bulk moduli at ambient conditions obtained from these equations almost coincide. However, the value, about 20 GPa, is appreciably small compared to the one reported previously. The x-ray diffraction patterns by which the current result is justified are presented. The possible origin of a large discrepancy in the values is discussed. [Copyright &y& Elsevier]

Abstract: Co–61.8at.% Si (CoSi–CoSi2) eutectic alloys were solidified on an electromagnetic levitator (EML) and an electrostatic levitator (ESL) at different undercooling levels. The results indicated that there is only a single recalescence event at low undercooling with the CoSi intermetallic compound as primary phase, which is independent of processing facilities, on either an EML or an ESL. The microstructure, however, is strongly dependent on the processing facility. The interior melt flow behavior in the sphere solidified at the EML differs substantially from that at the ESL, thus yielding different microstructures. On high undercooling, double recalescence takes place regardless of levitation condition. In situ X-ray diffraction of alloys solidified on the EML demonstrates that the CoSi2 compound becomes the primary phase upon the first recalescence, and the CoSi intermetallic phase crystallizes during the second recalescence. In addition to phase identification, real-time diffraction patterns can also provide additional evidence of the fragmentation of the primary phase and the ripening feature in the subsequent cooling process in the semisolid state. The phase competition between the CoSi and CoSi2 compounds is discussed when considering the nucleation barrier. The low interfacial energy of the CoSi2 phase favors a preferential nucleation event over the CoSi phase, which also plays a critical role in non-reciprocity nucleation and thus yields a double recalescence profile at high undercooling. [Copyright &y& Elsevier]

In situ X-ray diffraction experiments on FeS up to 22 GPa and 1600 K were carried out using large volume multianvil apparatus, combined with synchrotron radiation at SPring-8. We investigated phase stability relationships of FeS and determined the straight phase boundaries between FeS III (monoclinic phase) and FeS IV (hexagonal phase) to be T (K)=20P (GPa)+170 and between FeS IV and FeS V (NiAs-type phase) to be T (K)=39.6P (GPa)+450. We also found anomalous behavior in the c/a ratio, thermal expansion, and isothermal compression of FeS V as well as FeS IV, in the pressure range 4–12 GPa. These anomalies in FeS can be attributed to the spin-pairing transition of Fe, and divides FeS IV and FeS V into the high-spin low-pressure phase (LPP) and the possibly low-spin high-pressure phase (HPP). In order to investigate the internal structure of Mars, we evaluated the equations of state for FeS IV (HPP) and FeS V (HPP). A least square fit to the experimental data yielded K0T=62.5±0.9 GPa at T=600 K and (dK0/dT)P=-0.0208±0.0028 GPa/K for FeS IV (HPP), and K0T=54.3±1.0 GPa at T=1000 K and (dK0/dT)P=-0.0117±0.0015 GPa/K for FeS V (HPP) with fixed K′=4. Thermal expansion coefficients were α=7.16×10-5+6.08×10-8T for FeS IV (HPP) and α=10.42×10-5 for FeS V (HPP), respectively. Using these equations of state, we examined the internal structure of Mars that has a model mantle composition [Meteoritics 20 (1985) 367] and Fe–FeS core. Our models show that an Mg-silicate perovskite-rich lower mantle is stable only with the Fe-rich core having less than 20 wt.% sulfur. The polar moment of inertia factor C derived from Mars Pathfinder data [Science 278 (1997) 1749] is consistent with any compositions between Fe and FeS for the Martian core, but it excludes the presence of a crust thicker than 100 km. [Copyright &y& Elsevier]