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Several studies have reported association of altered levels of lipids and some trace elements with risk factors for cardiovascular disease development in adulthood. Accordingly, the present study aimed to determine the relationship among the serum levels of copper (Cu), zinc (Zn), lipids, lipoproteins and apolipoproteins in preterm infants through an assessment of atherogenic indices shortly after birth. Blood samples were collected within 20 min of birth from 45 preterm infants with gestational ages ranging from 32 to 35 weeks. Serum Cu, Zn, total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), apolipoprotein-A1 (apoA1) and apolipoprotein-B (apoB) levels were measured, and the TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios were calculated. Upon determining the correlation between the levels of Cu, Zn and these indices of lipid metabolism, triglyceride (TG) and Cu were found to correlate negatively with birth weight (BW) and the standard deviation (s.d.) score for body weight. Furthermore, Cu levels correlated positively with the TG level and TC/HDLc, LDLc/HDLc and apoB/apoA1 ratios and negatively with the HDLc level and HDLc/apoA1 ratios. However, a stepwise multiple regression analysis indicated that the s.d. score for BW and TG level were significant independent determinants of the Cu level. In contrast, Zn did not correlate with any of these indices. In conclusion, intrauterine growth restriction and the TG level at birth influence Cu levels in preterm infants, whereas atherogenic indices do not affect this parameter.
It is now firmly established that a small anisotropy of the galactic cosmic rays exists, observable from Earth as a variation of intensity in sidereal time. The problem now is to determine more clearly the characteristics of the anisotropy and, in particular, its detailed spatial structure and how it depends upon the energy and composition of the cosmic rays. This is a very difficult task and, in the final analysis, may not be fully achievable from Earth-based observations. The purpose of the present paper is to describe briefly an installation now operating in Tasmania to provide further information on the spatial structure of the anisotropy.
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.
The standard of care in the treatment of breast cancer and current recommendations for the diagnosis and treatment of breast cancer can be found in oncology textbooks and the guidelines from the National Comprehensive Cancer Network (www.nccn.org). Because breast cancers are generally sensitive to chemotherapy, it would seem logical that high-dose chemotherapy with stem cell support for metastatic disease would lead to higher remission rates and more durable remissions than those achieved by standard chemotherapy regimens and, in addition, might provide a potential for cure. After the initial optimism and promising findings from pilot and phase II studies, randomized studies were performed to compare high-dose chemotherapy with stem cell support and standard chemotherapy. Now, more than 15 years after the initiation of these studies, little evidence remains to support a role for autologous stem cell transplantation in the treatment of metastatic breast cancer (Vogl et al., 2006). In a 2005 Cochrane review in which six trials comparing high-dose chemotherapy with standard-dose chemotherapy for metastatic breast cancer were analyzed (Farquhar et al., 2005), no statistically significant difference was found in overall survival between the two groups at 1 year, 3 years, or 5 years of follow-up. However, a significant difference in event-free survival, favoring the high-dose group, was found at 1 and 5 years of follow-up. As expected, the toxicity of the treatment was significant in the high-dose chemotherapy group (mainly infections).
High-resolution angle resolved ultraviolet photoelectron spectroscopy measurements were conducted on rubrene single crystals successfully through relief of the sample charging assisted by a laser illumination. Significant dispersion of the valence band was clearly resolved. The band width W and the hole effective mass mh* were estimated to be 0.4 eV and 0.7m0, respectively, along the most conductive direction. The present results strongly suggest that the transport nature in rubrene single crystals should be described in the band transport framework of a delocalized charge carrier.
Directional information should play a significant role
for a firm detection of the galactic dark matter.
We developed a prototype three-dimensional gaseous tracking device
for a direction-sensitive dark matter direct detection.
We investigated the performance of the prototype detector and demonstrated
a direction-sensitive dark matter search experiment in a
We set the first limit
on the spin-dependent WIMP (Weakly Interacting Massive Particles)-proton cross s
ection by a direction-sensitive method.
Bi2Te3-based thin films were fabricated on glass substrates by the pulsed laser deposition (PLD) method. The vapor pressures of Bi and Te are significantly different, so controlling the stoichiometric composition is difficult when using conventional physical vapor deposition techniques, and the thermoelectric properties of Bi2Te3 films are sensitive to the film composition. PLD is a promising technique for the fabrication of telluride-based films such as Bi2Te3 due to its superior capability for controlling the film composition. Another advantage of PLD is the flexibility that it allows in terms of atmosphere in the reaction chamber; high concentrations of gases such as oxygen or argon can be introduced. We have measured various compositions of Bi2Te3 based films, and have identified the optimal compositions for both n-type and p-type material. The thermal conductivities of these Bi2Te3 films were evaluated by an exact measuring system, and the results were twice as low as those of conventional bulk materials. These results suggest that PLD has significant advantages for the deposition of in-plane Bi2Te3-based thin films.
The thermoelectric properties of Ni1-xCux (0<x<1) alloy are measured from 323K to 950K. The sample with optimized composition, Ni70Cu30 is found to possess large power factor value of 0.012 Wm−1K−2 at around 950K. Estimated figure of merit value ZT is 0.21 for Ni50Cu50 and 0.18 for Ni70Cu30 at the same temperature. A novel attempt of high-throughput parallel synthesis using multiple-wells is carried out to test the feasibility of combinatorial approach in this material system. The Seebeck coefficient is visualized over the multiple-wells combinatorial library and the other Ni-Cu composition-spread, and it is proved that further enhancement of throughput could be possible by conducting systematic experiments based on the combinatorial approaches performed in this study.
A three-dimensional finite element method is applied to
model a magnetic force control device. This device is based on the use of a
magnetostrictive rod in order to control the magnetic force applied to a
movable yoke. The paper introduces an original approach to model
magnetostrictive phenomena and presents comparisons between numerical and
A two-step heating schedule involving pulse electric current sintering, a kind of pressure-assisted vacuum sintering, and a subsequent postsintering in air was used to fabricate sintered porous alumina compacts. During pressure-assisted vacuum sintering, a dense microstructure of the Al2O3–C system was obtained and in the second stage (i.e., during postsintering in air at different temperatures ranging from 800 to 1300 °C for more than 10 h) carbon particles present in the Al2O3–C system burned out to form a highly porous Al2O3 compact. In this work, the porosity (30%) was successfully controlled and did not change with the postsintering temperature. The intriguing aspect of this study is that porous alumina compacts are fabricated with high strength and remain stable against the postsintering temperature and extended soaking time. This behavior merits the material fabricated here as a potential porous compact, mechanically withstanding for high-temperature applications.
Shredder residue is an unavoidable by-product of the treatment of end of life vehicles
and household appliances. NKK has developed a new post-treatment process in which the
residue is introduced in a bath of solvent made of hot tar and gives an overflow of plastics
and metallic sediments. The recovered plastics can be injected into the blast furnace and
the metallic parts recycled in the steel shop. This new process allows a high recycling
rate of treated materials.
Magnetic films for miniaturization of planar inductors operating at GHz frequencies require high resistivity and high ferro-magnetic resonance frequency. Y type magnetoplumbite Ba2Co2Fe12O22(Co2Y) is a candidate material to meet such requirements because it has about 10 &m resistivity and resonance frequency higher than 2 GHz. Recently we succeeded in the fabrication of Co2Y epitaxial thin film on MgAl2O4 substrate by combinatorial pulsed laser deposition technique . Here, we report on the magnetic and dielectric properties of this film. The DC resistivity of the film was 7.5 &m. The dielectric constant at 1.25 GHz was measured by a microwave microscope to be 11.0. An easy axis coercive force and saturation magnetization were about 145 Oe and 2000 Gauss respectively, being close to those of bulk sample. Furthermore, the magnetic micro domain structures of Co2Y epitaxial thin films were observed by a scanning SQUID microscope.
Thin films of Y-type magnetoplumbite (Ba2Co2Fe12O22: Co2Y) with such a huge unit cell length as 43.5 Å has been successfully fabricated for the first time with the aid of combinatorial optimization of pulsed laser deposition process. Planning a thickness gradient CoO buffer layer on MgAl2O4(111) substrate was very effective for prevent the phase separation of Co deficient impurity (BaFe2O4) to reside in the formation of desired Co2Y phase.From the TEM analysis, the CoO buffer layer of optimum thickness was incorporated into the Co2Y film to make theinterface with the make an atomically sharp.
In order to reduce specific contact resistance at via/interconnect interface and to avoid device degradation with Cu diffusion into dielectrics, via cleaning technology is a critical issue for a scaled down Cu multilevel metallization. Effects of cleaning processes are investigated for CHF3 plasma-etched SiO2/SiN/Cu via-structures. Effects of dilute HF (DHF) cleaning, hydrogen plasma cleaning, oxygen plasma cleaning, hexafluoroacetylacetone (H(hfac)) vapor cleaning, and vacuum anneal cleaning are investigated using an angle-resolved x-ray photoelectron spectroscopy (XPS). Cu contamination removal using dilute oxalic acid (DOA) is investigated using total reflection xray fluorescence analysis (TRXRF). Based on the results, we developed an optimized cleaning sequence which consists of a brief oxygen plasma exposure, DHF dipping, followed by exposure to H(hfac) vapors. The cleaning sequence is effective in obtaining a clean dielectric surface and an oxide-free Cu surface at via bottom. Direct-contacted via structures were fabricated by a dualdamascene process using the cleaning sequence. The specific contact resistance reduces to 20% of the reported values. We expect that the via resistance is low enough to be used in 0.13 µm generation and beyond.
Low temperature oxidation process of Si(100) substrates using atomic oxygen has been proposed. For the generation of atomic oxygen, microwave plasma remotely attached on the oxidation chamber was used. In the microwave plasma, the large amount of rare gas and a small amount of 02 gas mixture was supplied. The existence of the large amount of rare gas controls the plasma energy to some restricted values associated with the metastable states of the rare gas. Consequently, using Kr as mixed rare gas, atomic oxygen were efficiently generated instead of excited 02 molecules with any vibrational or ionized states. The oxidation kinetics of crystalline Si using this process was shown to be diffusion limiting, even if the oxide thickness was less than several nm. The activation energy of B, which is referred to as the parabolic rate constant, was found to be as low as 0.14eV In addition, lower interface trap density of 2.6 × 1011/cm2/eV at the mid gap could be achieved for the as-grown SiO2/Si(100) interface at the processing temperature of 500C.
Host-feeding by parasitoid wasps has been viewed as a positive attribute for biological control, because hosts are killed as a result of host-feeding in addition to parasitism. Host acceptance and host-feeding responses o unparasitized vs. conspecifically parasitized hosts by the parasitoid wasp Itoplectis naranyae Ashmead were studied in the laboratory. Female I. naranyae selected to oviposit in unparasitized hosts and those that had been parasitized I h previously, in equal proportions, even when allowed access to both types of host. Females also fed upon both types of host equally. Females, however, avoided ovipositing in hosts parasitized 40 h and 70 h previously, and preferentially fed upon them when allowed access both to parasitized and to unparasitized hosts. Parasitoid progeny in hosts which had been used for host-feeding suffered a high degree of mortality. Females used host internal changes as cues for deciding whether to feed on hosts. It is suggested that immature parasitoid mortality can be increased due to female preference for using parasitized hosts for host-feeding. Hence, host-feeding by I. naranyae may not be an advantageous biological control characteristic. The adaptive significance of selective host-feeding is also discussed.
Fully epitaxial Pb (Zr,Ti)O3(PZT)/MgO/Si(001) stacked structures, one of the potential components of ferroelectric-gate FETs, have been fabricated and characterized. According to the structural and electrical characterization of MgO/Si structures, epitaxially grown MgO thin films on the Si substrates showed a small leakage current of ∼ 10−8 A/cm2 at the electric field of 1 MV/cm. In the C-V measurements of the as-grown MgO/Si heteroepitaxial interfaces, injection-type hysteresis was observed because of the crystal defects in the MgO film adjacent to the interface. Using oxygen annealing with a temperature of 400 °C, it showed no hysteresis and a lower interface trap density of the order of 1011 cm−2eV−1 could be achieved with no formation of a low dielectric layer at the MgO/Si interface. These results indicate that the epitaxial MgO thin films are applicable as the gate insulators of FETs. After the PZT film was deposited on the MgO/Si structure, the C-V characteristic of the stacked structure showed a ferroelectric hysteresis curve and the low interface trap density of 5 × 1011 cm−2eV−1 A maximum memory window width of 1.2 V could be obtained in the PZT thin film on the Si substrate with a MgO intermediate layer.
It is demonstrated that luminescent porous silicon (PS) exhibits an efficient thermoacoustic effect owing to its extremely low thermal conductivity. The experimental device is composed of a patterned thin Al film electrode (30 nm thick), a microporous PS layer (10–50 μm thick), and a single-crystalline Si (c-Si) wafer. The PS layer was formed by a conventional anodization technique. When an electrical input is provided to the Al electrode as a sinusoidal current followed by Joule's heating, a significant acoustic pressure is produced in front of the device as a result of an efficient heat exchange between PS and air. The output amplitude is in inverse proportion to the square root of the input frequency (0.1-100 kHz) as predicted by a theoretical analysis. The observed effect is a novel useful function of PS as a completely depleted nanocrystalline system.
The transition from Al to Cu for advanced ULSI interconnects involves changes in architecture and deposition technique that will influence the microstructure and texture of the metal. Cu interconnects are typically formed within the confines of pre-patterned trenches and vias using an electroplating process with a sputtered Cu conduction layer deposited over a refractory metalbased diffusion barrier layer. In this paper, we focus on the influence of the barrier layer (PVD Ti/TiN, Ta, TaN, CVD TiN) and the effect of a vacuum break between barrier and conduction layer depositions, on the texture of the Cu lines, as examined by X-ray diffraction pole figure analysis.
A preferred (111) orientation was observed for all samples. The samples with no vacuum break between barrier and conduction layer deposition exhibited in plane anisotropy that was particularly pronounced for the Ta and TaN samples compared with the Ti/TiN sample. Focused ion beam images and transmission electron micrographs showed Cu grain size to be on the order of the trench width with a high degree of twinning, and no boundary could be distinguished between the PVD Cu conduction layer and the electroplated Cu.