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Evidence suggests that breastfeeding during infancy lowers the risk of metabolic syndrome (MS) and its attendant risk factors in adult life. To investigate the influence of feeding type on the risk factors of MS, we assessed insulin sensitivity and lipid and apolipoprotein metabolism in preterm infants. Blood samples were collected from preterm infants at the time of discharge. Infants were separated into two groups: a breast milk (BM) group receiving ⩾90% of their intake from BM, and a mixed-fed (MF) group receiving ⩾50% of their intake from formula. The following indices were then compared between the two groups. Blood glucose and serum insulin levels were used to calculate the quantitative insulin sensitivity check index (QUICKI). We also measured serum total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), apolipoprotein-A1 (apoA1) and apolipoprotein-B (apoB) levels, and the ratios of TC/HDLc, LDLc/HDLc and apoB/apoA1. The mean gestational age was 32.9 weeks at birth, and blood samples were collected at a mean corrected age of 37.4 weeks. There were 22 infants in the BM group and 19 in the MF group. QUICKI was significantly higher in the BM group. TC, HDLc and apoA1 were not significantly different between the groups, but LDLc and apoB levels were significantly higher in the BM group. The TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios were significantly higher in the BM group. In preterm infants, the type of feeding exposure in the early postnatal period may influence glucose, lipid and apolipoprotein metabolism, and affect markers of MS.
We present new and independent estimates of the distances to the Magellanic Clouds (MCs) using near-infrared (NIR) and optical–NIR period–Wesenheit (PW) relations. The slopes of the PW relations are, within the dispersion, linear over the entire period range and independent of metal content. The absolute zero points were fixed using Galactic Cepheids with distances based on the infrared surface-brightness method. The true distance modulus we found for the Large Magellanic Cloud—(m − M)0 = 18.48 ± 0.01 ± 0.10 mag—and the Small Magellanic Cloud—(m − M)0 = 18.94 ± 0.01 ± 0.10 mag—agree quite well with similar distance determinations based on robust distance indicators. We also briefly discuss the evolutionary and pulsation properties of MC Cepheids.
Phase-change materials undergo a change in bonding mechanism upon crystallization, which leads to pronounced modifications of the optical properties and is accompanied by an increase in average bond lengths as seen by extended x-ray absorption fine structure (EXAFS), neutron and x-ray diffraction. The reversible transition between a crystalline and an amorphous phase and its related property contrast are already employed in non-volatile data storage devices, such as rewritable optical discs and electronic memories. The crystalline phase of the prototypical material GeSb2Te4 is characterized by resonant bonding and pronounced disorder, which help to understand their optical and electrical properties, respectively. A change in bonding, however, should also affect the thermal properties, which will be addressed in this study. Based on EXAFS data analyses it will be shown that the thermal and static atomic displacements are larger in the meta-stable crystalline state. This indicates that the bonds become softer in the crystalline phase. At the same time, the bulk modulus increases upon crystallization. These observations are confirmed by the measured densities of phonon states (DPS), which reveal a vibrational softening of the optical modes upon crystallization. This demonstrates that the change of bonding upon crystallization in phase-change materials also has a profound impact on the lattice dynamics and the resulting thermal properties.
Epitaxial single crystal growth of zirconia (ZrO2) and yttria stabilized zirconia (ZrO2 ·Y2O3) films on sapphire substrates was achieved for the first time by using reactive sputtering. And the relations of crystallographic orientations between the epitaxial films and sapphire substrates was determined. Yttria stabilized zirconia films seem to offer hiah quality SOI substrates, since the crystal structure of ZrO2·Y2O3 is cubic fluorite and its lattice constant is closely matched to those of semiconductors such as Si and GaAs.
A high-energy (MeV) helium ion beam has been focused down to 1 μm by a combination of piezo-driven objective slits and a magnetic quadrupole doublet. Rutherford backscattering (RBS) mapping techniques using focused MeV ion beams were, for the first time, applied to multilayered structures of metals, isolated with insulators, representing a test structure for multilayered wiring or interconnections of integrated circuits to nondestructively analyze the imperfection of the structures.
We have performed ab-initio Hartree-Fock molecular orbital calculations of local atomic structures and chemical bonding states in Si-N covalent amorphous ceramics. Solute elements such as boron, carbon and oxygen were considered in the Si-N network, and the bonding characteristics around the solute elements were analyzed. When a nitrogen atom is substituted by a carbon atom, it was found that Si-C bonds reinforce the Si-N network due to strong covalency.
A seroepidemiological survey was conducted in Singapore to assess the prevalence of antibody to human parvovirus B19. Sera were collected from 600 healthy individuals between 6 months and over 50 years of age and tested for IgG antibody against B19 virus by antigen capture indirect immunosorbent assay. The overall seropositivity rate was 16·2%. All the children under 5 years of age were seronegative. Antibody prevalence increased gradually from 3·5% in school children (5–14 years of age) to 7·7% in age group 15–19 years and then to 10·3% in young adults (20–24 years of age). In the age group 25–34 years the prevalence was 28% and in the age group over 35 years 65% had parvovirus B19 antibody. The results of the survey indicate that there has been very low incidence of B19 virus infection in Singapore during the last two decades.
Length and weight of pigeonpea roots were measured weekly in different soil layers and compared with estimates obtained from a root simulation model using daily climatic data, soil physico-chemical properties and dry matter allocation to roots. Daily moisture content and temperature at different soil depths were well simulated using sub-routines from the CERES-Maize model. Daily allocation of dry matter to roots was calculated from logistic functions fitted to the growth data for shoots and roots. Although root length and weight tended to be underestimated by the model, regressions between measured and simulated root growth were highly significant so that the model could, with a few modifications, be used to predict root system development.
A row of two-dimensional vortices forms in an offshore zone when regular surface waves run up a sloping flat bed. This vortex row is called the offshore vortex train. The vortices begin to appear near the breaking point. Moving in the offshore direction, they develop and increase their horizontal lengthscale through vortex merging. After reaching a particular offshore location, however, they decay rapidly. The formation region of the vortex train has been investigated on the basis of visual experiments for three bed slopes. Its formation does not depend on the type of wave breaking but is observed when the steepness of deep-water waves is smaller than 4.2 × 10−2. The horizontal lengthscale of the vortices and the velocities of the vortex movement have also been evaluated empirically.