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Fabrication of dendritic Au rod (DAR) structures on Au surfaces via a simple electrodeposition from sulfite-based electrolytes containing Au(I) has been demonstrated. Scanning electron microscopic images show that the DAR structures contain highly faceted star-shaped protrusions in sub-100 nm scale. Electrochemical and X-ray diffraction results reveal that the DAR structures retain high amount of (110) and (100) crystalline domains on their surfaces. The unique morphology and surface orientation of DAR provide high electrocatalytic activities for glucose oxidation and oxygen reduction and efficient surface-enhanced Raman scattering activities.

The controlled synthesis of polyhedral Au nanocrystals (NCs) has attracted tremendous research interest in the past decades due to their promising applications in a variety of fields, such as plasmonics, sensors, electronics, catalysis, and surface-enhanced Raman scattering (SERS). Since the inherent plasmonic, electrical, and catalytic properties of Au NCs can be finely tuned by control over their shapes, numerous synthesis methods have been developed for the production polyhedral Au NCs with tailored morphologies, such as Platonic solids (tetrahedron, cube, octahedron, and icosahedron), cuboctahedron, decahedron, rod, and plate. To minimize the surface energy during the NC growth, these Au NCs are mostly enclosed by stable low-index {111} and/ or {100} facets. Recently, the synthesis of Au NCs with exposed high-energy facets, i.e., low-index {110} and highindex {hkl} (at least one index greater than 1), has been reported. NCs bound by high-energy facets have shown enhanced performance compared to conventional {111} and/ or {100}-faceted NCs due to the presence of high-density undercoordinated atoms on their surfaces as well as to their unique morphological characteristics. For instance, we reported that rhombic dodecahedral (RD) and hexoctahedral Au NCs exclusively bound by {110} and {321} facets, respectively, exhibited pronounced SERS activities. Nevertheless, it is still a great challenge to synthesize shapecontrolled NCs that are enclosed by high-index facets due to their high surface energy. Here we report for the first time on the synthesis of pentagonal dodecahedral (PD) Au NCs bound by high-index {hk0} facets. The PD Au NCs could be readily prepared by the reduction of Au precursors with N,N-dimethylformamide (DMF) in the presence of poly(vinyl pyrrolidone) (PVP). The pentagonal dodecahedron is a convex polyhedron with 12 pentagonal faces, where 3 faces meet at each corner. The surface facets of PD structures have been determined to be high-index {hk0}: the simplest one is {210} and other types are {320}, {410}, and {120}. The pentagonal dodecahedron has been known as a very unusual structure and crystalline materials with this structure have been rarely reported. Only the crystal of pyrite and some quasi crystals have this structure. To the best of our knowledge, the synthesis of metal NCs with PD structure has never been reported. Furthermore, the prepared PD Au NCs could be successfully applied in the field of SERS. Highly enhanced SERS signals could be obtained from various analytes with the PD Au NCs, which can be attributed to their high-surface energy facets. Figure 1(a) and (b) show representative lowand highmagnification field-emission scanning electron microscopy (FESEM) images of the as-prepared samples, demonstrating the formation of Au NCs with a well-defined structure. The sizes of Au NCs were in the range of 150-200 nm. The SEM image of NCs, shown in Figure 1(b), is closely matched by the 3D models of dodecahedra with different orientations (Figure 1(c)), indicating the successful generation of PD Au NCs enclosed by 12 pentagons under our experimental conditions. The X-ray diffraction (XRD) pattern of the PD Au NCs showed distinct diffraction peaks from the face centered cubic (fcc) structure of Au, revealing their crystalline nature (Figure 1(d)). Figure 2(a) shows the transmission electron microscopy (TEM) image of a PD Au NC recorded along the [110] direction. The corresponding convergent beam electron diffraction (CBED) pattern is also shown in Figure 2(b), which

One-pot synthesis of carbon-supported Pd-Au alloy nanoparticles with well-defined dendritic shape (Pd-Au(den)/C) was achieved by co-reduction of K(2)PdCl(4)/HAuCl(4) mixtures in a molar ratio of 1:1 with hydrazine in the presence of Vulcan XC-72R. The prepared Pd-Au(den)/C exhibited significantly enhanced performance in the electrocatalytic oxidation of ethanol compared with dendritic Pd nanoparticles and a commercial Pd/C catalyst. Pd-Au(den)/C even showed higher durability in electro-oxidation of ethanol than the supported catalyst prepared by the deposition of presynthesized dendritic Pd-Au nanoparticles on the carbon support. The experimental results clearly indicate that enhanced interaction between nanoparticle catalysts and carbon support through the one-pot synthesis protocol can improve the durability of the electrocatalysts.

The surface coating-dependent catalytic activity of icosahedral Au nanoparticles (IAuNPs) for the reduction of 4-nitrophenol by NaBH 4 in aqueous solution was investigated. Cetyltrimethylammonium bromide (CTAB)-stabilized IAuNPs with average size of 50 nm were prepared by three-step seeding protocol. The CTAB was then exchanged with several amine derivatives such as pyrrole, pyridine, 2,2′-bipyridine, and 4,4′-bipyridine. The catalytic reaction rates of nanoparticles are in the order of IAuNPs@4,4′-bpy > IAuNPs@2,2′-bpy > IAuNPs@pyridine > IAuNPs@pyrrole > IAuNPs@CTAB, revealing that the catalytic activity of the nanoparticles highly depends on the type and structure of the ligand molecules.

We have investigated a stability of oxide TFTs (IGZO) under electrical bias and monochromatic light illumination. Under -20 V gate bias, when 650 nm monochromatic illumination with intensity of 1 mW/cm2 was radiated, threshold voltage (Vth) was shifted by about -1.55 V while Vth was almost constant without illumination. Even though the photon energy of 650 nm is much smaller than optical band gap of oxide active layer (Eopt~3.0 eV), Vth was changed due to generation of carriers through localized state. However, under positive gate bias of 20 V, Vth was not changed with and without 650 nm light illumination. In terms of 300 nm wavelength light, Vth was shifted positively under negative bias stress and negatively under positive bias stress. It is considered that light affected not only the active layer but also the gate insulator layer.

To investigate the cyclic characteristics of exterior joints in RC frame buildings which are typically used after 1988, 70% scaled T-shaped beam-column subassemblies were designed and tested with a displacement control that is composed of 9 steps, until 3.5% story drift was reached. Axial forces are applied to columns during the experiment to simulate a real situation. The results show that the non-seismic detailed specimens failed before reaching 0.85% story drift, and their strengths are less than 0.85 times the nominal flexural strength which beam or columns should reach. The relationship of principal stress and story drift of exterior joints is similar to the one that Priestly proposed.

The two red clumps (RCs) observed in the color-magnitude diagram of the Milky Way bulge is widely accepted as evidence for an X-shaped structure originated from the bar instability. A drastically different interpretation has been suggested, however, based on the He-enhanced multiple stellar population phenomenon as is observed in globular clusters (GCs). Because these two scenarios imply very different pictures on the formation of the bulge and elliptical galaxies, understanding the origin of the double RC is of crucial importance. Here we report our discovery that the stars in the two RCs show a significant (> 5.3 {\sigma}) difference in CN-band strength, in stark contrast to that expected in the X-shaped bulge scenario. The difference in CN abundance and the population ratio between the two RCs are comparable to those observed in GCs between the first- and later generation stars. Since CN-strong stars trace a population with enhanced N, Na, and He abundances originated in GCs, this is direct evidence that the double RC is due to the multiple population phenomenon, and that a significant population of stars in the Milky Way bulge were assembled from disrupted proto-GCs. Our result also calls for the major revision of the 3D structure of the Milky Way bulge given that the current view is based on the previous interpretation of the double RC phenomenon., Comment: Accepted for publication in ApJL

We measure the UV-optical color dependence of galaxy clustering in the local universe. Using the clean separation of the red and blue sequences made possible by the NUV - r color-magnitude diagram, we segregate the galaxies into red, blue and intermediate "green" classes. We explore the clustering as a function of this segregation by removing the dependence on luminosity and by excluding edge-on galaxies as a means of a non-model dependent veto of highly extincted galaxies. We find that \xi (r_p, \pi) for both red and green galaxies shows strong redshift space distortion on small scales -- the "finger-of-God" effect, with green galaxies having a lower amplitude than is seen for the red sequence, and the blue sequence showing almost no distortion. On large scales, \xi (r_p, \pi) for all three samples show the effect of large-scale streaming from coherent infall. On scales 1 Mpc/h < r_p < 10 Mpc/h, the projected auto-correlation function w_p(r_p) for red and green galaxies fits a power-law with slope \gamma ~ 1.93 and amplitude r_0 ~ 7.5 and 5.3, compared with \gamma ~ 1.75 and r_0 ~ 3.9 Mpc/h for blue sequence galaxies. Compared to the clustering of a fiducial L* galaxy, the red, green, and blue have a relative bias of 1.5, 1.1, and 0.9 respectively. The w_p(r_p) for blue galaxies display an increase in convexity at ~ 1 Mpc/h, with an excess of large scale clustering. Our results suggest that the majority of blue galaxies are likely central galaxies in less massive halos, while red and green galaxies have larger satellite fractions, and preferentially reside in virialized structures. If blue sequence galaxies migrate to the red sequence via processes like mergers or quenching that take them through the green valley, such a transformation may be accompanied by a change in environment in addition to any change in luminosity and color.

Helicobacter pylori (H. pylori) infection causes chronic gastritis and gastric cancer. 15-Hydroxyprostaglandin dehydrogenase (15-PGDH) is a key enzyme that catalyzes the oxidation of prostaglandin E2 (PGE2) to 15-keto-PGE2. 15-PGDH is speculated as a tumor suppressor as its expression has been frequently down-regulated in diverse human malignancies including gastric cancer. However, the molecular mechanisms underlying 15-PGDH down-regulation in tumorigenesis remain largely unknown. In the present study, we found that the 15-PGDH expression was down-regulated in rat gastric mucosa (RGM)-1 cells infected with H. pylori. H. pylori induced hypermethylation of 15-PGDH promoter. The hypermethylation level of 15-PGDH was higher in the stomach biopsy from H. pylori-infected patients with gastritis than those without H. pylori infection. Notably, H. pylori induced the expression of DNA methyl transferase (DNMT) 1 through generation of reactive oxygen species (ROS). In H. pylori-infected C57BL/6 mice, 15-PGDH expression was reduced while DNMT1 expression was increased in the stomach tissues. In conclusion, H. pylori induces DNA methylation of CpG islands in the 15-PGDH promoter through up-regulation of DNMT1 expression, which is attributable to the generation of ROS.

Dendritic Au−Pd alloy nanoparticles were synthesized in high yield through the coreduction of HAuCl4 and K2PdCl4 in aqueous solutions by using hydrazine as a reducing agent. Relative compositions between Au and Pd at the particle surfaces as well as in bulk phases could be modulated by controlling the molar ratios between metal precursors in the feeding solutions. The formation of nanodendrites may be the result of the fast reduction rate of metal ions and subsequent fast, kinetically controlled growth of particles. The prepared alloy nanoparticles exhibit efficient electrocatalytic activities and stabilities toward ethanol oxidation in alkaline media. The enhanced electrocatalytic properties of dendritic particles can be attributed to the presence of a large number of active sites on their surfaces.

There is a growing body of evidence for the presence of multiple stellar populations in some globular clusters, including NGC 1851. For most of these peculiar globular clusters, however, the evidence for the multiple red giant-branches (RGBs) having different heavy elemental abundances as observed in Omega Centauri is hitherto lacking, although spreads in some lighter elements are reported. It is therefore not clear whether they also share the suggested dwarf galaxy origin of Omega Cen or not. Here we show from the CTIO 4m UVI photometry of the globular cluster NGC 1851 that its RGB is clearly split into two in the U - I color. The two distinct RGB populations are also clearly separated in the abundance of heavy elements as traced by Calcium, suggesting that the type II supernovae enrichment is also responsible, in addition to the pollutions of lighter elements by intermediate mass asymptotic giant branch stars or fast-rotating massive stars. The RGB split, however, is not shown in the V - I color, as indicated by previous observations. Our stellar population models show that this and the presence of bimodal horizontal-branch distribution in NGC 1851 can be naturally reproduced if the metal-rich second generation stars are also enhanced in helium., Comment: 13 pages, 4 figures, accepted for publication in the Astrophysical Journal Letters

One possible channel for the formation of dwarf galaxies involves birth in the tidal tails of interacting galaxies. We report the detection of a bright UV tidal tail and several young tidal dwarf galaxy candidates in the post-merger galaxy NGC 4922 in the Coma cluster. Based on a two-component population model (combining young and old stellar populations), we find that the light of tidal tail predominantly comes from young stars (a few Myr old). The Galaxy Evolution Explorer (GALEX) ultraviolet data played a critical role in the parameter (age and mass) estimation. Our stellar mass estimates of the tidal dwarf galaxy candidates are ~ 10^{6-7} M_sun, typical for dwarf galaxies., Comment: 10 pages, 7 figures, 2 tables - Published in AJ; v2 Minor revision to match published version

In the “varieties of capitalism” debate, scholars have paid considerable attention to the question of whether Korea and Japan have left behind their interventionist political economy for neo-liberal reform. In this paper, we re-examine the scholarly consensus that Korea has become a neo-liberal state, while Japan has not changed much. On the basis of our comparison of the extent of the two countries’ neo-liberal reforms using the “business systems framework” developed by Witt, we demonstrate that neo-liberal reforms observed in Korea and Japan are not substantially different enough to warrant the view that the two countries have taken divergent paths of institutional development. With this finding, we call for further empirical study, including the development and use of more qualitative data. We suggest that the future direction research should take on this issue in order to make theoretical contributions to the existing literature on institutional change and continuity in “non-liberal” capitali...

In this paper, we concern about the distribution characteristics of surface temperature by the increment of time, diffusivity and heat flux on irradiating of a laser. The penetration depth corresponding to the induced constant heat flux or irradiated laser, is simulated by a computer algorithm. The distribution of temperature versus penetration depth for the variation of time and diffusivity is characterized at the constant heat flux and on irradiating of a laser. The temperature of constant heat flux at the fixed diffusivity or time, is decreased by the pattern of exponential function as the time t or diffusivity α is increased (α=10, 100, 1000). The temperature of constant heat flux is not changed but exponentially fixed with the increasing diffusivity and the fixed time. On the other hand, the temperature of laser at the fixed diffusivity or time is decreased linearly. Our results show that the characteristics of the simulated surface temperature in a semi-infinite solid are similar to the graphs on theoretical consideration.

Absolute gravity measurements were made to calibrate Korea’s first superconducting gravimeter (SG) at MunGyung (MG, Mungyeong) Observatory. A calibration coefficient (CC) of the MG SG was determined by a parallel registration with an FG5 absolute gravimeter. A total of 8,541 drops were measured over a period of 37 hours between October 8th and 10th, 2007. We first determined the absolute gravity value to be 979,859,179.3 ± 88.481 μGal (νGal=10−8 m·s−2) after atmospheric pressure, Earth tide and ocean loading corrections. In a linear regression analysis between the FG5 recordings and the raw SG data, a CC of 64.548 ± 0.224 μGal· volt−1 was determined, having previously removed invalid drops and outliers from the data sets. Together with the absolute measurements, a vertical gravity gradient of 2.72 μGal·cm−1 was calculated using a Graviton-EG spring gravimeter to take the absolute gravity value down to the SG observatory platform level. The validity of the CC was additionally tested by a comparison between the recorded SG data and the theoretical tides (HW95 and Wahr-Dehant models) as reference. Gravity variations induced by atmospheric pressure and ocean loading were added to the theoretical Earth tides. The CC based on the theoretical tide was determined to be 64.560 μGal·volt−1. The difference between the two coefficients is 0.012 μGal·volt−1, which lies within the standard error of the determined coefficient, 0.224 μGal·volt−1. Therefore, a value of 64.548 μGal·volt−1, determined by the parallel registration with the absolute gravimeter, was accepted as the CC of the SG (GWR Instrument Inc. #045) installed at MG Observatory. During the gravity measurements, the other gravity values and heights such as normal gravity and the gravity gradient, orthometric and dynamic heights were also calculated.

We present a detailed study of the Galaxy Evolution Explorer's photometric catalogs with special focus on the statistical properties of the All-sky and Medium Imaging Surveys. We introduce the concept of primaries to resolve the issue of multiple detections and follow a geometric approach to define clean catalogs with well-understood selection functions. We cross-identify the GALEX sources (GR2+3) with Sloan Digital Sky Survey (DR6) observations, which indirectly provides an invaluable insight about the astrometric model of the UV sources and allows us to revise the band merging strategy. We derive the formal description of the GALEX footprints as well as their intersections with the SDSS coverage along with analytic calculations of their areal coverage. The crossmatch catalogs are made available for the public. We conclude by illustrating the implementation of typical selection criteria in SQL for catalog subsets geared toward statistical analyses, e.g., correlation and luminosity function studies., Comment: 12 pages, 15 figures, accepted to ApJ

We investigate the red giant branch (RGB) subpopulations of NGC 1851 using Ca uvby photometry. Our color-magnitude diagrams show that the RGB stars have two subpopulations and the RGB stars in NGC 1851 appear to have distinct elemental abundance patterns with the [Ca/H] abundance. We discuss that the elemental abundance patterns can be explained by the contributions from the asymptotic giant stars, confirming the previous studies by others. The RR Lyrae variables in NGC 1851 appear to have a large metallicity spread and, perhaps, a bimodal metallicity distribution. Our period shift analysis of the RR Lyrae variables shows that the helium enhancement appears to be insignificant in the NGC 1851 RR Lyrae population. However, the helium enrichment scenario in the blue or the red parts of horizontal branch (HB) cannot be completely ruled out. Our results show that about 18% of the bright RGB stars have enhanced CNO abundances, sharply in contrast to previous estimates by others (38%), making it difficult to explain the double subgiant, RGB sequences, and the bimodal HB distribution by their number ratios.

Multi-branched gold nanoparticles were synthesized in high-yield through the reduction of HAuCl 4 by using hydrazine as a reducing agent. Practically 100% of the particles have numerous branches. The high reduction capability of hydrazine is found to be crucial for the formation of these branched gold nanoparticles. Their size can be controlled from 20 to 130 nm by varying the amounts of hydrazine. The prepared nanoparticles exhibit efficient surface-enhanced Raman scattering (SERS) properties and the SERS activity of the particles depends on the aspect ratio of their branches, which are most likely related to a great increase in the localized electromagnetic field enhancement from their unique sharp surface features arising from the branches.

Nanocrystalline gold octahedrons were synthesized in an aqueous environment via the reduction of HAuCl4 by ascorbic acid with the addition of NaOH. Highly monodisperse octahedral particles with controlled sizes ranging from 20 to 40 nm were prepared in high-yield by varying the reaction temperature. The structural and optical properties of the synthesized gold nanoparticles were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and UV–vis spectroscopy. The prepared nanoparticles exhibited efficient surface-enhanced Raman scattering (SERS) properties, and their SERS activities were highly size-dependent.

The GALEX (Galaxy Evolution Explorer) spectroscopic survey mode, with a resolution of about 8 A in the FUV (1350 - 1750 A) and about 20 A in the NUV (1950 - 2750 A) is used for a systematic search of Ly-a emitting galaxies at low redshift. This aims at filling a gap between high-redshift surveys and a small set of objects studied in detail in the nearby universe. A blind search of 7018 spectra extracted in 5 deep exposures (5.65 sq.deg) has resulted in 96 Ly-a emitting galaxy candidates in the FUV domain, after accounting for broad-line AGNs. The Ly-a EWs (equivalent width) are consistent with stellar population model predictions and show no trends as a function of UV color or UV luminosity, except a possible decrease in the most luminous that may be due to small-number statistics. Their distribution in EW is similar to that at z about 3 but their fraction among star-forming galaxies is smaller. Avoiding uncertain candidates, a sub-sample of 66 objects in the range 0.2 < z < 0.35 has been used to build a Ly-a LF (luminosity function). The incompleteness due to objects with significant Ly-a emission but a UV continuum too low for spectral extraction has been evaluated. A comparison with H-a LF in the same redshift domain is consistent with an average Ly-a/H-a of about 1 in about 15 % of the star-forming galaxies. A comparison with high-redshift Ly-a LFs implies an increase of the Ly-a luminosity density by a factor of about 16 from z about 0.3 to z about 3. By comparison with the factor 5 increase of the UV luminosity density in the same redshift range, this suggests an increase of the average Ly-a escape fraction with redshift.

The displacement of the SAMP GPS station located in Medan City, Indonesia, is analyzed by means of an on-line point positioning method, the Canadian Spatial Reference System-Precise Point Positioning (CSRS-PPP). Based on the comparison of the results obtained with those from previous studies, we propose that CSRS-PPP can be applied to analyses of the displacement of a GPS station. Previous studies have focused solely on the “Sumatra-Andaman Islands Earthquake of December 26, 2004”; in contrast, we provide here an in-depth analysis of the crustal movements at the SAMP station for an expanded period of 2.5 years. CSRS-PPP, an Internet data processing service of the Department of Natural Resources Canada (NRCan), was used to process the data obtained at the SAMP station from January 2004 to July 2006. The data show a clear displacement in the southwestern direction from December 26, 2004 to March 28, 2005 when two major earthquakes occurred. However, after the midpoint of 2005, the data show displacement at a regular speed. In particular, the “Sumatra-Andaman Islands Earthquake (M w = 9.0) of December 26, 2004” led to a displacement of 0.1387 m (dn = −0.0122 m, de = −0.1382 m) to the southwest. The earthquake (M w = 8.7) that occurred on March 28, 2005 led to a displacement of 0.1921 m (dn = −0.1400 m, de = −0.1315 m) to the southwest. Starting from December 26, 2004, displacement to the southwest continued. From April 2005, however, the speed of the displacement gradually slowed down. The dn variation shows a displacement at a regular rate (−55.69 mm/year) from April 28, 2005 to July 2006, while the de variation shows a displacement at a regular rate (−23.66 mm/year) from July 5, 2005 to July 2006.

Despite the efforts of the past decade, the origin of the bimodal horizontal-branch (HB) found in some globular clusters (GCs) remains a conundrum. Inspired by the discovery of multiple stellar populations in the {\it most massive} Galactic GC, $\omega$ Centauri, we investigate the possibility that two distinct populations may coexist and are responsible for the bimodal HBs in the {\it third} and {\it fifth} brightest GCs, NGC 6388 and NGC 6441. Using the population synthesis technique, we examine two different chemical ``self-enrichment'' hypotheses in which a primordial GC was sufficiently massive to contain two or more distinct populations as suggested by the populations found in $\omega$ Cen: (1) the age-metallicity relation scenario in which two populations with different metallicity and age coexist, following an internal age-metallicity relation, and (2) the super-helium-rich scenario in which GCs contain a certain fraction of helium-enhanced stars, for instance, the second generation stars formed from the helium-enriched ejecta of the first. The comparative study indicates that the detailed color-magnitude diagram morphologies and the properties of the RR Lyrae variables in NGC 6388 and NGC 6441 support the latter scenario; i.e., the model which assumes a minor fraction ($\sim$ 15 %) of helium-excess (Y $\simeq$ 0.3) stars. The results suggest that helium content is the main driver behind the HB bimodality found most often in massive GCs. If confirmed, the GC-to-GC variation of helium abundance should be considered a {\it local} effect, further supporting the argument that age is the {\it global} second parameter of HB morphology., Comment: Accepted in ApJ, 33 pages, 5 figures, 4 tables

A facile synthesis of flower-shaped porous Au−Pd alloy nanoparticles with ascorbic acid as a reductant and PVP as a stabilizing agent is presented. The alloy nanoparticles were prepared from the aqueous solutions of HAuCl4/K2PdCl4 mixtures in molar ratios of 3:1, 1:1, and 1:3. The size, structure, optical properties, and composition distribution of the synthesized Au−Pd alloy nanoparticles were characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy, UV−vis spectroscopy, and X-ray diffraction. The experimental results for the bimetallic systems and the physical mixtures of individual monometallic nanoparticles revealed that unstable small nanoparticles aggregate into the three-dimensional flower-shaped nanoparticles and the prepared nanoparticles are Au−Pd alloys. The surfaces of Au−Pd alloy nanoparticles were characterized by cyclic voltammetry measurement in 0.1 M HClO4 and surface-enhanced Raman scattering spectra of 1,4-phenylene diisocyanide adsorbed thereon. All alloy...

The Yonsei-Yale Isochrones have been widely used since its birth in 2001. We announce a major upgrade mainly making varieties of helium values available. The recent works on the globular clusters with extreme helium abundances have called for such a need. The new version of the Y2 Isochrones are available for [α/Fe] = 0 through 0.6, ΔY/ΔZ = 1.5 through 3.0, and extreme helium abundances (Y = normal 0.05, 0.1, 0.15, 0.2), and for 11 metallicity grids, with full capability of interpolation. The database will be powerful for making population models. Besides, the accuracy of the models on the lower main sequence has been substantially improved. We illustrate the major upgrades and demonstrate the power of the new grids.

We present the measurement of radial velocities for globular clusters in M60, giant elliptical galaxy in the Virgo cluster. Target globular cluster candidates were selected using the Washington photometry based on the deep $16\arcmin \times 16\arcmin$ images taken at the KPNO 4m and using the $VI$ photometry derived from the HST/WFPC2 archive images. The spectra of the target objects were obtained using the Multi-Object Spectrograph (MOS) at the Canada-France-Hawaii Telescope (CFHT). We have measured the radial velocity for 111 objects in the field of M60: 93 globular clusters (72 blue globular clusters with $1.0\le(C-T_1)

A fast and simple one-step method for the fabrication of stable gold nanoparticles-silica composites by using 1,4,7,10,13,16,21,24-octaazabicyclo[8.8.8]hexacosane(azacryptand) as a molecular anchor between nanoparticles and silica as well as reductant and stabilizer in the formation of the nanoparticles is reported. Gold nanoparticles-coated silica materials can be fabricated by mixing HAuCl 4 aqueous solution with the aqueous mixture of azacryptand and silica materials such as submicrometer silica particles and silica gel. The prepared nanoparticles-coated silica gel can effectively catalyze reduction of 4-nitrophenol by sodium borohydride in aqueous solution.

We describe the calibration status and data products pertaining to the GR2 and GR3 data releases of the Galaxy Evolution Explorer (GALEX). These releases have identical pipeline calibrations that are significantly improved over the GR1 data release. GALEX continues to survey the sky in the far-ultraviolet (FUV, ~154 nm) and near-ultraviolet (NUV, ~232 nm) bands, providing simultaneous imaging with a pair of photon-counting, microchannel plate, delay line readout detectors. These 1.25° field of view detectors are well suited to ultraviolet observations because of their excellent red rejection and negligible background. A dithered mode of observing and photon list output pose complex requirements on the data processing pipeline, entangling detector calibrations, and aspect reconstruction algorithms. Recent improvements have achieved photometric repeatability of 0.05 and 0.03 m_(AB) in the FUV and NUV, respectively. We have detected a long-term drift of order 1% FUV and 6% NUV over the mission. Astrometric precision is of order 0.5" rms in both bands. In this paper we provide the GALEX user with a broad overview of the calibration issues likely to be confronted in the current release. Improvements are likely as the GALEX mission continues into an extended phase with a healthy instrument, no consumables, and increased opportunities for guest investigations.

We use GALEX/optical photometry to construct color-color relationships for early-type galaxies sorted by morphological type. We have matched objects in the GALEX GR1 public release and the first IR1.1 internal release, with the RC3 early-type galaxies having a morphological type -5.5, Comment: 25 pages, 5 figures, accepted for publication in ApJS (abstract abridged), typos corrected in section 2.1

We present ultraviolet (UV) photometry of M31 globular clusters (GCs) found in 23 Galaxy Evolution Explorer (GALEX) images covering the entirety of M31. We detect 485 and 273 GCs (and GC candidates) in the near-ultraviolet (NUV; 2267 A) and far-ultraviolet (FUV; 1516 A), respectively. Comparing M31 data with those of Galactic GCs in the UV with the aid of population models, we find that the age ranges of old GCs in M31 and the Galactic halo are similar. Three metal-rich ([Fe/H]>-1) GCs in M31 produce significant FUV flux making their FUV-V colors unusually blue for their metallicities. These are thought to be analogs of the two peculiar Galactic GCs NGC 6388 and NGC 6441 with extended blue HB stars. Based on the models incorporating helium enriched subpopulations in addition to the majority of the population that have a normal helium abundance, we suggest that even small fraction of super-helium-rich subpopulations in GCs can reproduce the observed UV bright metal-rich GCs. Young clusters in M31 show distinct UV and optical properties from GCs in Milky Way. Population models indicate that their typical age is less than ~ 2 Gyrs. A large fraction of young GCs have the kinematics of the thin, rapidly rotating disk component. However, a subset of the old GCs also shares the thin-disk kinematics of the younger clusters. The existence of young GCs on the outskirts of M31 disk suggests the occurrence of a significant recent star formation in the thin-disk of M31. Old thin-disk GCs may set constraints on the epoch of early formation of the M31 thin-disk. We detect 12 (10) intermediate-age GC candidates in NUV (FUV). We suggest that some of spectroscopically identified intermediate-age GCs may not be truly intermediate in age, but rather older GCs that possess developed HB., 43 pages, 14 figures, accepted for the GALEX special issue of ApJS

We report on the properties of a sample of ultraviolet-luminous galaxies (UVLGs) selected by matching the Galaxy Evolution Explorer (GALEX) All-Sky Imaging and Medium Imaging Surveys with the Sloan Digital Sky Survey third data release. The overlap between these two surveys is roughly 450 deg^2. Of 25,362 galaxies (with SDSS spectroscopy) in the range 0.0 < z < 0.3 detected by GALEX, there are 215 galaxies with L > 2 × 10^(10) L_☉ at 1530 Å (observed wavelength). The properties of this population are well correlated with ultraviolet surface brightness. We find that the galaxies with low UV surface brightness are primarily large spiral systems with a mixture of old and young stellar populations, while the high surface brightness galaxies consist primarily of compact starburst systems, with an approximate boundary at a surface brightness of I_(1530) = 10^8 L_☉ kpc^(−2). The large galaxies appear to be the high-luminosity tail of the galaxy star formation function and owe their large luminosity to their large surface area. In terms of the behavior of surface brightness with luminosity, size with luminosity, the mass-metallicity relation, and other parameters, the compact UVLGs clearly depart from the trends established by the full sample of galaxies. The subset of compact UVLGs with the highest surface brightness (I_(1530) > 10^9 L_☉ kpc^(−2); "supercompact UVLGs") have characteristics that are remarkably similar to Lyman break galaxies at higher redshift. They are much more luminous (and thus have much higher star formation rates) than typical local ultraviolet-bright starburst galaxies and blue compact dwarf galaxies. They have metallicities that are systematically lower than normal galaxies of the same stellar mass, indicating that they are less chemically evolved. In all these respects, they are the best local analogs for Lyman break galaxies.

A new solution-phase method for synthesis of metal nanoparticles–carbon nanotubes (CNTs) assemblies is described. By injection of CNTs solution into the diethyl ether/aqueous solution of metal salt biphasic mixture, metal (Ag, Au, Pd, and Pt) nanoparticles–decorated CNTs composite materials can be prepared. Metal nanoparticles have spontaneously and selectively formed on the sidewalls of CNTs through redox reaction between CNTs and metal ions. This phenomenon has been probed by transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray analysis, and Raman spectroscopy.

About 25% of the Milky Way globular clusters (GCs) exhibit unusually extended color distribution of stars in the horizontal-branch (HB) phase. This phenomenon is now best understood as due to the presence of helium enhanced second generation subpopulations, which has raised a possibility that these peculiar GCs might have a unique origin. Here we show that these GCs with extended HB are clearly distinct from other normal GCs in kinematics and mass. The GCs with extended HB are more massive than normal GCs, and are dominated by random motion with no correlation between kinematics and metallicity. Surprisingly, however, when they are excluded, most normal GCs in the inner halo show clear signs of dissipational collapse that apparently led to the formation of the disk. Normal GCs in the outer halo share their kinematic properties with the extended HB GCs, which is consistent with the accretion origin. Our result further suggests heterogeneous origins of GCs, and we anticipate this to be a starting point for more detailed investigations of Milky Way formation, including early mergers, collapse, and later accretion., Comment: Accepted for publication in ApJ Letters

The presence of two red clumps (RCs) in high latitude fields of the Milky Way bulge is interpreted as evidence for an X-shaped structure originated from the bar instability. Here we show, however, that this double RC phenomenon is more likely to be another manifestation of multiple populations observed in globular clusters (GCs) in the metal-rich regime. As in the bulge GC Terzan 5, the helium enhanced second generation stars (G2) in the classical bulge component of the Milky Way are placed on the bright RC, which is about 0.5 mag brighter than the normal RC originated from the first generation stars (G1), producing the observed double RC. In a composite bulge, where a classical bulge can coexist with a boxy pseudo bulge, our models can also reproduce key observations, such as the dependence of the double RC feature on metallicity and Galactic latitude and longitude. If confirmed by Gaia trigonometric parallax distances, this would indicate that the Milky Way bar is not sufficiently buckled to form the X-shaped structure in the bulge, and suggest that the early-type galaxies would be similarly prevailed by super-helium-rich subpopulation., Accepted for publication in MNRAS

In our recent investigation of the Oosterhoff dichotomy in the multiple population paradigm (Jang et al. 2014), we have suggested that the RR Lyrae variables in the Oosterhoff groups I, II, and III globular clusters (GCs) are produced mostly by the first, second, and third generation stars (G1, G2, and G3), respectively. Here we show, for the first time, that the observed dichotomies in the inner and outer halo GCs can be naturally reproduced when these models are extended to all metallicity regimes, while maintaining reasonable agreements in the horizontal-branch type versus [Fe/H] correlations. In order to achieve this, however, specific star formation histories are required for the inner and outer halos. In the inner halo GCs, the star formation commenced and ceased earlier with relatively short formation timescale between the subpopulations (~0.5 Gyr), while in the outer halo, the formation of G1 was delayed by ~0.8 Gyr with more extended timescale between G1 and G2 (~1.4 Gyr). This is consistent with the dual origin of the Milky Way halo. Despite the difference in detail, our models show that the Oosterhoff period groups observed in both outer and inner halo GCs are all manifestations of the "population-shift" effect within the instability strip, for which the origin can be traced back to the two or three discrete episodes of star formation in GCs., Accepted for publication in ApJS

A facile aqueous synthesis method for the preparation of Au nanoparticle clusters by the controlled galvanic replacement of Ag nanoparticles with Au precursors is described. The prepared clusters showed both significantly enhanced surface-enhanced Raman scattering activity and stability.

In our recent investigation (Lim et al. 2015), we have shown that narrow-band photometry can be combined with low-resolution spectroscopy to effectively search for globular clusters (GCs) with supernovae (SNe) enrichments. Here we apply this technique to the metal-poor bulge GC NGC 6273, and find that the red giant branch stars in this GC are clearly divided into two distinct subpopulations having different calcium abun- dances. The Ca rich subpopulation in this GC is also enhanced in CN and CH, showing a positive correlation between them. This trend is identical to the result we found in M22, suggesting that this might be a ubiquitous nature of GCs more strongly affected by SNe in their chemical evolution. Our results suggest that NGC 6273 was massive enough to retain SNe ejecta which would place this cluster in the growing group of GCs with Galactic building block characteristics, such as {\omega} Centauri and Terzan 5., Comment: 5 pages, 5 figures, accepted for the publication in ApJL

The aqueous-phase synthesis of icosahedral gold nanoparticles with controlled diameters ranging from 10 to 90 nm is reported. The nanoparticles were prepared by a seed-mediated growth approach. Citrate-capped 3.5 nm gold nanoparticles, prepared by reduction of HAuCl4 with sodium borohydride, are used as seeds. Cetyltrimethylammonium bromide molecules served as a capping agent to restrict the nanoparticles size. The synthesized gold nanoparticles were characterized by UV−vis spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy, and X-ray diffraction (XRD). The crystal structure of the particles was found to consist of mostly {111} surfaces as revealed by both TEM and XRD results. The prepared icosahedral gold nanoparticles show efficient surface-enhanced Raman scattering properties.

The aqueous-phase synthesis of polyhedral gold nanoparticles with remarkably narrow size distribution is reported. By using a seeding growth approach, icosahedral gold particles with controllable size can be synthesized in high-yield. Citrate-capped 3.5 nm gold nanoparticles, prepared by the reduction of HAuCl 4 with sodium borohydride, are used as seeds. The synthesized gold nanoparticles were characterized by transmission electron microscopy, scanning electron microscopy, and X-ray diffraction. The prepared gold nanoparticles show efficient surface-enhanced Raman scattering activities.

We combine data from SDSS and the GALEX and Spitzer observatories to create a sample of galaxies observed homogeneously from the UV to the Far-IR. This sample, consisting of ~460 galaxies observed spectroscopically by SDSS provides a multiwavelength (0.15-24 micron) view of obscured and unobscured star formation in nearby (z, 4 pages, 3 figures, accepted by ApJ Letters

Nonseismic designed RC frame have a possibility of shear failure because of deficiencies of reinforcing details. To model the shear failure in numerical analysis, shear strength degradation models which Include Moehle`s and ATC 40 are compared and applied to push-over analysis. For numerical analysis, three storied building frame is selected and designed according to Korean Concrete Design Code(2003). As results, It is shown that Moehle`s shear strength degradation model estimates the shear strength lower than NZSEE model and has less variation than ATC 40 model and all the shear strengths of models are greater than the nominal shear strength of ACI 318. Also, from the numerical analysis, it is pointed out that there may be great difference in lateral drift capacity if a different shear strength model is used. And the capacity can be severely underestimated if the restraining model of plastic rotation of ATC 40 is used, compared to the use of shear spring model for shear degradation.

According to revisions of survey law taking effect on January 1, 2003, the Korean geodetic datum has been changed from a local geodetic to a world geodetic system. Since the datum change demands a geographical data transformation, the National Geographic Information Institute has established step-by-step plans for the transformation of the land data constructed through the National GIS Project, and it is in progress. For maritime data, however, no detailed transformation plan has been established yet. Therefore, it is necessary to analyze the maritime geographic data obtained through the Maritime GIS project and set up the data transformation scheme to a world geodetic system. In this study, the datum transformation parameters especially for the maritime geographical data are determined. From database constructed through MGIS, a total of 492 coordinate pairs were used in parameter determination initially. At this stage, three popular seven parameter transformation models, Bursa-Wolf, Molodensky and Veis model, and the multi regression equation are applied, and the transformation parameters from the Molodensky model are selected for its accuracy and consistency with the land data transformation method. To eliminate the local bias caused by the nonequally distributed stations, a network optimization is applied and 42 stations are selected to determine the final transformation parameters. The distortion after applying the similarity transformation is modeled through a least squares collocation with Gaussian model, and high accuracy better than 15 cm in coordinate transformation is obtained.

We present version 1.0 of the NASA Galaxy Evolution Explorer (GALEX) ultraviolet variability (GUVV) catalog, which contains information on 84 time-variable and transient sources gained with simultaneous near-ultraviolet (NUV) and far-ultraviolet (FUV) photometric observations. These time-variable sources were serendipitously revealed in the various 12 diameter star fields currently being surveyed by the GALEX satellite in two ultraviolet bands (NUV 1750–2750 A, FUV 1350–1750 A) with limiting AB magnitudes of 23–25. The largest amplitude variable objects currently detected by GALEX are M dwarf flare stars, which can brighten by 5–10 mag in both the NUV and FUV bands during short-duration (

Recent observations for the color-magnitude diagrams (CMDs) of the massive globular cluster Omega Centauri have shown that it has a striking double main sequence (MS), with a minority population of bluer and fainter MS well separated from a majority population of MS stars. Here we confirm, with the most up-to-date Y2 isochrones, that this special feature can only be reproduced by assuming a large variation (Delta Y = 0.15) of primordial helium abundance among several distinct populations in this cluster. We further show that the same helium enhancement required for this special feature on the MS can by itself reproduce the extreme horizontal-branch (HB) stars observed in Omega Cen, which are hotter than normal HB stars. Similarly, the complex features on the HBs of other globular clusters, such as NGC 2808, are explained by large internal variations of helium abundance. Supporting evidence for the helium-rich population is also provided by the far-UV (FUV) observations of extreme HB stars in these clusters, where the enhancement of helium can naturally explain the observed fainter FUV luminosity for these stars. The presence of super helium-rich populations in some globular clusters suggests that the third parameter, other than metallicity and age, also influences CMD morphology of these clusters., 4 pages, 4 figures, accepted for publication in the Astrophysical Journal Letters

We present the first Galaxy Evolution Explorer (GALEX) UV images of the well-known interacting group of galaxies, Stephan's Quintet (SQ). We detect widespread UV emission throughout the group. However, there is no consistent coincidence between UV structure and emission in the optical, Hα, or H I. Excluding the foreground galaxy NGC 7320 (Sd), most of the UV emission is found in regions associated with the two spiral members of the group, NGC 7319 and NGC 7318b, and the intragroup medium starburst SQ-A. The extinction-corrected UV data are analyzed to investigate the overall star formation activity in SQ. We find that the total star formation rate (SFR) of SQ is 6.69 ± 0.65 M☉ yr-1. Of this, 1.34 ± 0.16 M☉ yr-1 is due to SQ-A. This is in excellent agreement with that derived from the extinction-corrected Hα luminosity of SQ-A. The SFR in regions related to NGC 7319 is 1.98 ± 0.58 M☉ yr-1, most of which (68%) is contributed by the disk. The contribution from the young tail is only 15%. In the UV, the young tail is more extended (~100 kpc) and shows a looplike structure, including the optical tail, the extragalactic H II regions recently discovered in Hα, and other UV emission regions discovered for the first time. The UV and optical colors of the old tail are consistent with a single stellar population of age t 108.5±0.4 yr. The UV emission associated with NGC 7318b is found in a very large (~80 kpc) disk, with a net SFR of 3.37 ± 0.25 M☉ yr-1. Several large UV emission regions are 30-40 kpc away from the nucleus of NGC 7318b. Although both NGC 7319 and NGC 7318b show peculiar UV morphology, their SFR is consistent with that of normal Sbc galaxies, indicating that the strength of star formation activity is not enhanced by interactions.

We present GALEX FUV (1530 A) and NUV (2310 A) observations of the archetypal merging system NGC 4038/39, ``The Antennae". Both tails are relatively bright in the UV, especially in the vicinity of the Tidal Dwarf Galaxy candidates at the end of the southern tail. The UV light generally falls within the optically delineated tails, although the UV light is considerably more structured, with a remarkably similar morphology to the tidal HI. The UV colors suggest that there has been continuing star formation within the tidal tails, even outside the previously studied Tidal Dwarf regions. Within the inner disk regions, there are interesting UV features which appear to be related to the extended soft X-ray loops and halo recently discovered by CHANDRA.

We present the results of a determination of the galaxy luminosity function at ultraviolet wavelengths at redshifts of $z=0.0-0.1$ from GALEX data. We determined the luminosity function in the GALEX FUV and NUV bands from a sample of galaxies with UV magnitudes between 17 and 20 that are drawn from a total of 56.73 deg^2 of GALEX fields overlapping the b_j-selected 2dF Galaxy Redshift Survey. The resulting luminosity functions are fainter than previous UV estimates and result in total UV luminosity densities of 10^(25.55+/-0.12) ergs s^-1 Hz^-1 Mpc^-3 and 10^(25.72+/-0.12) ergs s^-1 Hz^-1 Mpc^-3 at 1530 Ang. and 2310 Ang., respectively. This corresponds to a local star formation rate density in agreement with previous estimates made with H-alpha-selected data for reasonable assumptions about the UV extinction.