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In this paper, a colloidal solution of copper nanoparticles was prepared from a Cu ion aqueous solution with the protein casein surfactant by a liquid phase reduction method at low temperature below 373K. For the casein concentration ranging from 6g/L to 75g/L, the formation of copper nanoparticle colloid were observed. As a result, the peak was observed at the ranging of 450 to 650 nm corresponding to the copper nanoparticle colloid plasmon absorption. As the surfactant concentration increases, the absorption spectrum tends to blue-shift and the particle diameter decreases. Thus, it indicated that the optical property and particle diameter of copper nanoparticle colloidal solution will be controlled by the protein casein surfactant concentration.
Adipose tissue (AT) dysfunction links obesity of any cause with cardiometabolic disease, but whether early-life nutritional deficiency can program adipocyte dysfunction independently of obesity is untested. In 3–5-month-old juvenile microswine offspring exposed to isocaloric perinatal maternal protein restriction (MPR) and exhibiting accelerated prepubertal fat accrual without obesity, we assessed markers of acquired obesity: adiponectin and tumor necrosis factor (TNF)-α messenger ribonucleic acid (mRNA) levels and adipocyte size in intra-abdominal (ABD-AT) and subcutaneous (SC-AT) adipose tissues. Plasma cortisol, leptin and insulin levels were measured in fetal, neonatal and juvenile offspring. In juvenile low-protein offspring (LPO), adipocyte size in ABD-AT was reduced 22% (P = 0.011 v. controls), whereas adipocyte size in SC-AT was increased in female LPO (P = 0.05) and normal in male LPO; yet, adiponectin mRNA in LPO was low in both sexes and in both depots (P < 0.001). Plasma leptin (P = 0.004) and cortisol (P < 0.05) were reduced only in neonatal LPO during MPR. In juveniles, correlations between % body fat and adiponectin mRNA, TNF-α mRNA or plasma leptin were significant in normal-protein offspring (NPO) but absent in LPO. Plasma glucose in juvenile LPO was increased in males but decreased in females (interaction, P = 0.023); plasma insulin levels and insulin sensitivity were unaffected. Findings support nutritional programming of adipocyte size and gene expression and subtly altered glucose homeostasis. Reduced adiponectin mRNA and adipokine dysregulation in juvenile LPO following accelerated growth occurred independently of obesity, adipocyte hypertrophy or inflammatory markers; thus, perinatal MPR and/or growth acceleration can alter adipocyte structure and disturb adipokine homeostasis in metabolically adverse patterns predictive of enhanced disease risk.
Poor fetal growth and associated prepubertal growth acceleration are linked to increased risk of cardiometabolic dysfunction in later life, but whether obesity is integral to ‘catch-up’ growth and its ensuing risks are unknown. In microswine offspring exposed to perinatal maternal protein restriction (MPR), we measured body and organ sizes (during MPR); linear growth and weight gain (birth to 5 months of age); feed intake and utilization efficiency (5–14 weeks); and body composition at 6 and 11 weeks of age (by dual-energy X-ray absorptiometry, DEXA). During MPR, low protein offspring (LPO) showed asymmetric growth restriction with reduced body weight (Wt):length (Lth) at birth and elevated heart Wt:liver Wt ratio by 2 weeks of age. In LPO, after slow early postnatal growth (0–5 weeks), subsequent linear growth on ad libitum normal feed was absolutely accelerated (cm/week; P < 0.001) over 6–11 weeks but normal thereafter, whereas absolute weight gain (kg/week) was similar to controls but accelerated relative to lower LPO nadir weights. Concurrently, rates of fat and lean tissue accrual in LPO over 6–11 weeks were similar to normal protein offspring in absolute terms (g/5 weeks) but increased relative to lower mass at 6 weeks, yielding normal lean:Lth but reduced fat:Lth ratios at 11 weeks. LPO had higher relative feed intake (g/kg/meal) in both sexes and higher feed efficiency in females over 5–11 weeks of age. Findings suggest that postnatal linear growth acceleration preserved thinness in juvenile LPO. Given separately reported abnormalities of vascular (Bagby et al., 2011) and adipocyte function in juvenile LPO, (DuPriest et al., 2011) findings demonstrate that perinatal MPR programs catch-up growth and cardiovascular abnormalities independently of obesity.
In the article by Crabtree et al., published in Transactions IAU, Volume XXVIIIA there was an error in the list of authors. Pedro Russo was not included in the list of authors on the organizing committee. The editors apologise to Pedro Russo for this error. The correct authorship is published below:
PRESIDENT: Dennis R. Crabtree
VICE-PRESIDENT: Lars Lindberg Christensen
PAST PRESIDENT: Ian Robson
ORGANIZING COMMITTEE: Oscar Alvarez Pomare, Augusto Damineli Neto, Richard T. Fienberg, Anne Green, Ajit K. Kembhavi, Pedro Russo, Kazuhiro Sekiguchi, Patricia Ann Whitelock, Jin Zhu
Commission 55 was approved at the IAU General Assembly in Prague following the great success of the Communicating Astronomy Working Group, which had been set up in 2003. It resides within Division XII and the mission statement of the Working Group has been incorporated into the Commission:
• To encourage and enable a much larger fraction of the astronomical community to take an active role in explaining what we do (and why) to our fellow citizens.
• To act as an international, impartial coordinating entity that furthers the recognition of outreach and public communication on all levels in astronomy.
• To encourage international collaborations on outreach and public communication.
• To endorse standards, best practices and requirements for public communication.
Since its formation at the XXVI General Assembly in Prague in 2006, amazing progress has been made by Commission 55, all due to the work of the key activists and enthusiasts. The web-page for the Commission contains a wealth of information and is one of the key foundations and tools for the Commission. The web address is http://www.communicatingastronomy.org
Commission 55 was approved at the IAU XXVI General Assembly in Prague, 2006, following the great success of the Working Group Communicating Astronomy, which had been set up in 2003.
Luminescence properties of Yb-doped Ca-α-SiAlON phosphors with composition of Ca1−xYbxSi12−(m+n)Alm+nOnN16−n were investigated by using cathodoluminescence (CL). The ratio of Yb to Ca was kept constant while the host lattice was changed by replacing m+n(Si–N) bonds with m(Al–N) and n(Al–O) bonds. The luminescence of these phosphors consists of three peaks in the ultraviolet (UV), green (VIS), and infrared (IR) regions, which are attributed to the emissions from secondary phases, Yb2+ and Yb3+, respectively. The UV emission depends on the Si/Al ratio: the UV peak is centered at 310 nm for the Si-rich mix and at 360 nm for the Al-rich mix. We have found that Yb exists in the divalent state in α-SiAlON and in the trivalent state in the secondary phases.
Ce3+-activated lanthanide silicon oxynitride (La5Si3O12N, La4SiO7N2, LaSiO2N, and La3Si8O4N11) phosphors were prepared by firing the mixture of La2O3, Si3N4, SiO2, and CeO2 at 1500–1600 °C under a 0.5 MPa nitrogen atmosphere. Diffuse reflection spectrum, photoluminescence spectra, and temperature-dependent luminescence of these phosphors are presented in this work. A blue emission of Ce3+ in all lanthanide silicon oxynitrides was observed under ultraviolet irradiation, which is strongest in La3Si8O4N11:Ce3+. The concentration quenching and thermal quenching of the samples were discussed.
Pre-encounter ground-based thermal observations of NEA 25143 Itokawa at 10μm led to a size prediction of 520(±50) × 270(±30) × 230(±20)m, corresponding to an effective diameter of DTPMeff= 318m (Müller et al.2005). This is in almost perfect agreement with the final in-situ results 535 × 294 × 209m (DHayabusaeff= 320m; Demura et al.2006). The corresponding radar value, based on the same shape model (Kaasalainen et al.2005), were about 20% too high: 594 × 320 × 288m (DRadareff= 379m; Ostro et al.2005). The very simple N-band observations revealed a surface which is dominated by bare rocks rather than a thick regolith layer. This prediction was nicely confirmed by the Hayabusa mission (e.g., Fujiwara et al.2006; Saito et al.2006). The ground-based measurements covered three different phase angles which enabled us to determine the thermal properties with unprecedented accuracy and in excellent agreement with the results from the touch-down measurements (Okada et al.2006; Yano et al.2006). These thermal values are also key ingredients for high precision Yarkovsky and YORP calculations (mainly the rotation slowing) for Itokawa (e.g., Vokrouhlický et al.2004; Vokrouhlický et al.2005). In addition to the above mentioned properties, our data allowed us to derive the surface albedo and to estimate the total mass. We believe that with our well-tested and calibrated radiometric techniques (Lagerros 1996,1997,1998; Müller & Lagerros 1998, 2002; Müller 2002) we have tools at hand to distinguish between monolithic, regolith-covered and rubble pile near-Earth objects by only using remote thermal observations. This project also emphasizes the high and so far not yet fully exploited potential of thermophysical modeling techniques for the NEA/NEO exploration.
We report an on-going blank-field multi-wavelength deep and wide survey of the Subaru/XMM-Newton Deep Survey Field (SXDF). The SXDF has been the focus of a wide range of multi-wavelength observing programs spanning the X-ray to the radio. These observations cover a large enough area (the initial optical imaging covers $\sim$1.3 deg$^{2}$) and depth ($B=28.2$) that they are not affected by large-scale structures (which exist on tens of Mpc scales) and allow us to study the distribution and evolution of high-$z$ galaxies and AGNs, and thus constrain theories for their formation. Our early results include: i) an indication of the primeval Large Scale Structure (LSS) at z $\sim$ 5.7, ii) an indication for the down-sizing of galaxy formation at z $\sim$ 1, iii) identifications of passively evolving systems, and evidence for early formation and the passive evolution of present-day early-type galaxies, and iv) discovery of a large number of optically obscured QSOs. As for the next step forward - we express our hope to use the next generation optical/IR Extremely Large Telescopes (ELTs) to obtain larger and deeper spectroscopy samples of the high-$z$ objects.
The light curves for three eclipsing binaries in the Magellanic Clouds have been obtained using CCD uVJIC photometry. One target in the LMC, MACHO*05:36:48.7−69:17:00, is an eccentric system, e = 0.20, with a period of 3.853534 ± 0.000005 d. Initial solutions indicate a primary component in the range Teff,1 = 20,000−35,000K and the secondary Teff,2 1000−2000K cooler than the primary, with inclinations ranging i = 84.2° − 86.0°. Two targets in the SMC, MOA J005018.4-723855 and MOA J005623.5−722123, have periods of 1.8399±0.0004 and 2.3199 ± 0.0003 days respectively. Both have circular orbits with the former being a semi-detached system.
We have characterized threading dislocations (TDs) and misfit
dislocations (MDs) in a degraded strained-Si/SiGe heterostructure by using
electron beam induced current (EBIC), transmission electron microscopy (TEM)
and chemical etching techniques. The strained-Si layer in this degraded
heterostructure was selected to be thicker than the critical thickness for
introducing MDs at the interface of strained-Si/SiGe. Cross-sectional TEM
image reveals that there are dense dislocation network in deep region (graded
SiGe layer) and 60° MDs at the upper interface (strained-Si/SiGe
interface). The EBIC image taken with a 20 keV electron beam reveals the
cross-hatch pattern of MD network in the deep graded SiGe region.
The EBIC image taken with a 4 keV electron beam at 65 K shows weak dark
spots and two perpendicular sets of weak dark lines, corresponded to TDs
and MDs at the upper interface, respectively. Comparison with chemical etching
results indicates that the weak dark lines in EBIC image correspond to MD
bundles/groups at the upper interface. The electrical activities of these
dislocations are discussed by using the temperature dependence of EBIC
contrast.
We have developed a method for growing high quality multicrystalline silicon
(mc-Si) ingots for high efficiency solar cells. Grain size of the mc-Si wafers
was controlled by the multi-stage solidification method. Impurity
concentrations in the mc-Si ingots were also reduced by several ways. The
efficiency of mc-Si solar cells produced from such mc-Si wafers has reached
18.3% with a cell area of 25 cm2. In this paper we have investigated this
high quality mc-Si by means of electron-beam induced current (EBIC),
transmission electron microscopy combined with energy-dispersive X-ray
analysis (TEM-EDX), and secondary-ion mass-spectroscopy (SIMS). EBIC results
revealed that grain boundaries in MUST mc-Si were electrically inactive at
room temperature. No metal impurities were detected at these grain boundaries.
Two kinds of widegap-semiconductor nanowires, Tb-doped AlN
nanowire arrays on Si and free-standing BN nanowires, were
fabricated by different catalyst-free methods. Well-aligned
Tb-doped AlN nanowire arrays were grown on the Si (111)
substrate by magnetron sputtering method. Free-standing BN
nanowires were grown by heat-treatment of B-N-O precursor and
graphite powders. The crystal structure of nanowires was
characterized by using X-ray diffraction and transmission
electron microscopy. Cathodoluminescence (CL) observation was
performed with a field emission scanning electron microscope
operating with an electron beam lower than 5 kV. CL spectra
mapping as well as monochromatic CL imaging clearly revealed
not only the variation of the luminescence spectra of different
nanowires but also that along the single wire. Our results
demonstrates the advantage of CL for the characterization of
nanowires.
More than 4000 stars observed in both MOA and DENIS projects showing periodic or quasi-periodic light curves are studied. Almost all Mira stars are located on the classical period-luminosity relation, and the multiplicity of the period-luminosity relation is confirmed for small-amplitude stars. The colour-magnitude diagrams based on the MOA red band, Rm, and Ks constructed for the sequences, form a single strip with small successive shifts.
We studied 147 long-period red variable stars in the Large Magellanic Cloud from the MOA database. Amongst them, seven red luminous stars are likely pulsating in a higher mode.
The work of Commission 25 covers a wide range of topics concerning the measurement of magnitude, colour and polarisation of astronomical objects. As such, the area of interest covers virtually every field of astrophysical research in the visual and infrared spectral domain. Our reports cover some aspects of photometry and polarimetry as a technique rather than being an account of research highlights over the last three years.
A review of the MOA (Microlensing Observations in Astrophysics) project is presented. MOA is a collaboration of approximately 30 astronomers from New Zealand and Japan established with the aim of finding and detecting microlensing events towards the Magellanic Clouds and the Galactic bulge, which may be indicative of either dark matter or of planetary companions. The observing program commenced in 1995, using very wide band blue and red filters and a nine-chip mosaic CCD camera.
As a by-product of these observations a large database of CCD photometry for 1.4 million stars towards both LMC and SMC has been established. In one preliminary analysis 576 bright variable stars were confirmed, nearly half of them being Cepheids. Another analysis has identified large numbers of blue variables, and 205 eclipsing binaries are included in this sample. In addition 351 red variables (AGB stars) have been found. Light curves have been obtained for all these stars. The observations are carried out on a 61-cm f/6.25 telescope at Mt John University Observatory where a new larger CCD camera was installed in 1998 July. From this latitude (44° S) the Magellanic Clouds can be monitored throughout the year.
The red variables whose amplitude is larger than 1.3 mag in the MOA database are studied for the LMC. Among 3 196 such stars, 532 stars are likely to be Miras or red semiregular variables. The period–colour relation of these stars is shown.