OGLE-2015-BLG-1482L: The First Isolated Low-mass Microlens in the Galactic Bulge

Chung, S.-J.,Zhu, W.,Udalski, A.,Lee, C.-U.,Ryu, Y.-H.,Jung, Y. K.,Shin, I.-G.,Yee, J. C.,Hwang, K.-H.,Gould, A.,Albrow, M.,Cha, S.-M.,Han, C.,Kim, D.-J.,Kim, H.-W.,Kim, S.-L.,Kim, Y.-H.,Lee, Y.,Park, American Astronomical Society 2017 The Astrophysical Journal Vol.838 No.2

<P>We analyze the single microlensing event OGLE-2015-BLG-1482 simultaneously observed from two ground-based surveys and from Spitzer. The Spitzer data exhibit finite-source effects that are. due to the passage of the lens close to or directly over. the surface of the source star as seen from Spitzer. Such finite-source effects generally yield measurements of the angular Einstein radius, which when combined with the microlens parallax derived from a comparison between the ground-based and the Spitzer light curves. yields the lens mass and lens-source relative parallax. From this analysis, we find that the lens of OGLE-2015-BLG-1482 is a very low-mass star with a. mass 0.10 +/- 0.02 M-circle dot or a brown dwarf with a. mass 55 +/- 9MJ, which are. located at D-LS = 0.80 +/- 0.19 kpc and D-LS = 0.54 +/- 0.08 kpc, respectively,. where DLS is the distance between the lens and the source, and thus it is the first isolated low-mass microlens that has been decisively located in the Galactic bulge. The degeneracy between the two solutions is severe ( Delta chi(2) = 0.3). The fundamental reason for the degeneracy is that the finite-source effect is seen only in a single data point from Spitzer, and this single data point gives rise to two solutions for rho, the angular size of the source in units of the angular Einstein ring radius. Because the rho degeneracy can be resolved only by relatively high-cadence observations around the peak, while the Spitzer cadence is typically similar to 1 day(-1), we expect that events for which the finite-source effect is seen only in the Spitzer data may frequently exhibit this rho degeneracy. For OGLE-2015-BLG-1482, the relative proper motion of the lens and source for the low-mass star is mu(rel) = 9.0 +/- 1.9 mas yr(-1), while for the brown dwarf it is 5.5 +/- 0.5 mas yr(-1). Hence, the degeneracy can be resolved within similar to 10 years from direct-lens imaging by using next-generation instruments with high spatial resolution.</P>

OGLE-2017-BLG-0173Lb: Low-mass-ratio Planet in a “Hollywood” Microlensing Event

Hwang, K.-H.,Udalski, A.,Shvartzvald, Y.,Ryu, Y.-H.,Albrow, M. D.,Chung, S.-J.,Gould, A.,Han, C.,Jung, Y. K.,Shin, I.-G.,Yee, J. C.,Zhu, W.,Cha, S.-M.,Kim, D.-J.,Kim, H.-W.,Kim, S.-L.,Lee, C.-U.,Lee, American Astronomical Society 2018 The Astronomical journal Vol.155 No.1

<P>We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either q similar or equal to 2.5 x 10(-5) or q similar or equal to 6.5 x 10(-5), the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Delta chi(2) similar to 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planetary caustic: a so-called 'Hollywood' event. The factor similar to 2.5 offset in q arises because of a previously unrecognized discrete degeneracy between Hollywood events in which the caustic is fully enveloped and those in which only one flank is enveloped, which we dub 'Cannae' and 'von Schlieffen,' respectively. This degeneracy is 'accidental' in that it arises from gaps in the data. Nevertheless, the fact that it appears in a Delta chi(2) = 10000 planetary anomaly is striking. We present a simple formalism to estimate the sensitivity of other Hollywood events to planets and show that they can lead to detections close to, but perhaps not quite reaching, the Earth/Sun mass ratio of 3 x 10(-6). This formalism also enables an analytic understanding of the factor similar to 2.5 offset in q between the Cannae and von Schlieffen solutions. The Bayesian estimates for the host mass, system distance, and planet-host projected separation are M = 0.39(-0.24)(+0.40) M circle dot, D-L = 4.8(-1.8)(+1.5) kpc, and a(perpendicular to) = 3.8 +/- 1.6 au, respectively. The two estimates of the planet mass are m(p) = 3.3(2.1)(+3.8) M circle plus and m(p) = 8(6)(+11) M circle plus. The measured lens-source relative proper motion mu = 6 mas yr(-1) will permit imaging of the lens in about 15 years or at first light on adaptive-optics imagers on next-generation telescopes. These will allow one to measure the host mass but probably will not be able to resolve the planet-host mass-ratio degeneracy.</P>

Topiramate Improves Neuroblast Differentiation of Hippocampal Dentate Gyrus in the d-Galactose-Induced Aging Mice via Its Antioxidant Effects

Shen, H.,Wang, J.,Jiang, D.,Xu, P.,Zhu, X.,Zhang, Y.,Yu, X.,Won, M. H.,Su, P. Q.,Yan, B. C. Springer Science + Business Media 2017 Cellular and molecular neurobiology Vol.37 No.5

<P>Some anticonvulsant drugs are associated with cognitive ability in patients; Topiramate (TPM) is well known as an effective anticonvulsant agent applied in clinical settings. However, the effect of TPM on the cognitive function is rarely studied. In this study, we aimed to observe the effects of TPM on cell proliferation and neuronal differentiation in the dentate gyrus (DG) of the d-galactose-induced aging mice by Ki-67 and doublecortin (DCX) immunohistochemistry. The study is divided into four groups including control, d-galactose-treated group, 25 and 50 mg/kg TPM-treated plus d-galactose-treated groups. We found, 50 mg/kg (not 25 mg/kg) TPM treatment significantly increased the numbers of Ki-67(+) cells and DCX immunoreactivity, and improved neuroblast injury induced by d-galactose treatment. In addition, we also found that decreased immunoreactivities and protein levels of antioxidants including superoxide dismutase and catalase induced by d-galactose treatment were significantly recovered by 50 mg/kg TPM treatment in the mice hippocampal DG (P < 0.05). In conclusion, our present results indicate that TPM can ameliorate neuroblast damage and promote cell proliferation and neuroblast differentiation in the hippocampal DG via increasing SODs and catalase levels in the d-galactose mice.</P>

OGLE-2016-BLG-1469L: Microlensing Binary Composed of Brown Dwarfs

Han, C.,Udalski, A.,Sumi, T.,Gould, A.,Albrow, M. D.,Chung, S.-J.,Jung, Y. K.,Ryu, Y.-H.,Shin, I.-G.,Yee, J. C.,Zhu, W.,Cha, S.-M.,Kim, S.-L.,Kim, D.-J.,Lee, C.-U.,Lee, Y.,Park, B.-G.,Soszyń,ski, American Astronomical Society 2017 The Astrophysical journal Vol.843 No.1

<P>We report the discovery of a binary composed of two brown dwarfs, based on the analysis of the microlensing event OGLE-2016-BLG-1469. Thanks to the detection of both finite-source and microlens-parallax effects, we are able to measure both the masses M-1 similar to 0.05M(circle dot) and. M-2 similar to 0.01M(circle dot), and the. distance D-L similar to 4.5 kpc, as well as the projected separation a(perpendicular to) similar to 0.33 au. This is the third brown-dwarf binary detected using the microlensing method, demonstrating the usefulness of microlensing in detecting field brown-dwarf binaries with separations of less than 1 au.</P>

Ground-based Parallax Confirmed by<i>Spitzer</i>: Binary Microlensing Event MOA-2015-BLG-020

Wang, Tianshu,Zhu, Wei,Mao, Shude,Bond, I. A.,Gould, A.,Udalski, A.,Sumi, T.,Bozza, V.,Ranc, C.,Cassan, A.,Yee, J. C.,Han, C.,Abe, F.,Asakura, Y.,Barry, R.,Bennett, D. P.,Bhattacharya, A.,Donachie, M. American Astronomical Society 2017 The Astrophysical journal Vol.845 No.2

<P>We present the analysis of the binary gravitational microlensing event MOA-2015-BLG-020. The event has a fairly long timescale (similar to 63 days) and thus the light curve deviates significantly from the lensing model that is based on the rectilinear lens-source relative motion. This enables us to measure the microlensing parallax through the annual parallax effect. The microlensing parallax parameters constrained by the ground-based data are confirmed by the Spitzer observations through the satellite parallax method. By additionally measuring the angular Einstein radius from the analysis of the resolved caustic crossing, the physical parameters of the lens are determined. It is found that the binary lens is composed of two dwarf stars with masses M-1= 0.606 +/- 0.028M(circle dot) and M-2= 0.125 +/- 0.006 M-circle dot in the Galactic disk. Assuming that the source star is at the same distance as the bulge red clump stars, we find the lens is at a distance D-L = 2.44 +/- 0.10 kpc. We also provide a summary and short discussion of all of the published microlensing events in which the annual parallax effect is confirmed by other independent observations.</P>

Reflection states in Ding-Iohara-Miki algebra and brane-web for D-type quiver

Bourgine, J.-E.,Fukuda, M.,Matsuo, Y.,Zhu, R.-D. Springer-Verlag 2017 Journal of high energy physics Vol.2017 No.12

Effect of diets with different energy and lipase levels on performance, digestibility and carcass trait in broilers

Hu, Y.D.,Lan, D.,Zhu, Y.,Pang, H.Z.,Mu, X.P.,Hu, X.F. Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.8

Objective: A 28-d trial was conducted to evaluate the effect of diets with different energy and lipase levels on performance, nutrient digestibility, serum profiles, gut health, and carcass quality in broilers. Methods: A total of 720 one-day-old male Ross 308 broilers ($45.4{\pm}0.5g$) were randomly assigned to one of the following four treatments: i) RET, reduced energy treatment (metabolizable energy = 2,950 and 3,100 kcal/kg for starter and finisher diet), ii) BDT, basal diet treatment (metabolizable energy = 3,050 and 3,200 kcal/kg for starter and finisher diet, iii) RET015, RET+0.15 g/kg lipase, and iv) RET03, RET+0.3 g/kg lipase. There were 10 replications (cages) per treatment with 18 birds per cage. Results: During d 1 to 14, broilers fed BDT, RET015, and RET03 diets had higher (p<0.05) body weight gain than those fed RET diet. During d 1 to 14, 15 to 28 and the overall experiment, feed conversion ratio in RET03 treatment was lower (p<0.05) compared with RET treatment. On d 14, the apparent total tract digestibility (ATTD) of dry matter (DM), ether extract (EE), and gross energy in RET03 treatment was higher (p<0.05) than those in RET treatment, while the ATTD of N was increased (p<0.05) by RET03 treatment. On d 28, broilers fed RET03 diet had higher (p<0.05) ATTD of DM than those fed RET and RET015 diets, while the ATTD of EE in BDT and RET03 treatments was increased (p<0.05) compared with RET and RET015 treatments. Broilers fed RET03 diet had higher villus height (VH) and VH:crypt depth (CD) ratio than those fed RET and BDT diets. The activity of pancreatic lipase in BDT and RET03 treatments was higher (p<0.05) than that in RET treatment. Conclusion: Taken together, lipase supplementation (3,000 U/kg feed) increased growth performance, nutrient digestibility, VH, VH:CD ratio and lipase activity, but decreased triglyceride, low-density lipoprotein cholesterol and the abdominal fat percentage in broilers fed reduced energy diet.

Toward a Galactic Distribution of Planets. I. Methodology and Planet Sensitivities of the 2015 High-cadence<i>Spitzer</i>Microlens Sample

Zhu, Wei,Udalski, A.,Novati, S. Calchi,Chung, S.-J.,Jung, Y. K.,Ryu, Y.-H.,Shin, I.-G.,Gould, A.,Lee, C.-U.,Albrow, M. D.,Yee, J. C.,Han, C.,Hwang, K.-H.,Cha, S.-M.,Kim, D.-J.,Kim, H.-W.,Kim, S.-L.,Ki American Institute of Physics 2017 The Astronomical journal Vol.154 No.5

<P>We analyze an ensemble of microlensing events from the 2015 Spitzer microlensing campaign, all of which were densely monitored by ground-based high-cadence survey teams. The simultaneous observations from Spitzer and the ground yield measurements of the microlensing parallax vector pi(E), from which compact constraints on the microlens properties are derived, including less than or similar to 25% uncertainties on the lens mass and distance. With the current sample, we demonstrate that the majority of microlenses are indeed in the mass range of M dwarfs. The planet sensitivities of all 41 events in the sample are calculated, from which we provide constraints on the planet distribution function. In particular, assuming a planet distribution function that is uniform in log q, where q is the planet-to-star mass ratio, we find a 95% upper limit on the fraction of stars that host typical microlensing planets of 49%, which is consistent with previous studies. Based on this planet-free sample, we develop the methodology to statistically study the Galactic distribution of planets using microlensing parallax measurements. Under the assumption that the planet distributions are the same in the bulge as in the disk, we predict that similar to 1/3 of all planet detections from the microlensing campaigns with Spitzer should be in the bulge. This prediction will be tested with a much larger sample, and deviations from it can be used to constrain the abundance of planets in the bulge relative to the disk.</P>

Measurement of aerodynamic coefficients of tower components of Tsing Ma Bridge under yaw winds

Zhu, L.D.,Xu, Y.L.,Zhang, F.,Xiang, H.F. Techno-Press 2003 Wind and Structures, An International Journal (WAS Vol.6 No.1

Tsing Ma Bridge in Hong Kong is the longest suspension bridge in the world carrying both highway and railway. It has two H-shape concrete towers, each of which is composed of two reinforced concrete legs and four deep transverse prestressed concrete beams. A series of wind tunnel tests have been performed to measure the aerodynamic coefficients of the tower legs and transverse beams in various arrangements. A 1:100 scaled 3D rigid model of the full bridge tower assembled from various tower components has been constructed for different test cases. The aerodynamic coefficients of the lower and upper segments of the windward and leeward tower legs and those of the transverse beams at different levels, with and without the dummy bridge deck model, were measured as a function of yaw wind angle. The effects of wind interference among the tower components and the influence of the bridge deck on the tower aerodynamic coefficients were also investigated. The results achieved can be used as the pertinent data for the comparison of the computed and field-measured fully coupled buffeting responses of the entire bridge under yaw winds.

녹차의 항당뇨 효과에 관한 연구

D.-Y. Zhu,X.-Y. Li,F.-X. Jiang,Y.-D. Yang,J. Zhou,Y. Ye,M. Kubo,H. Nishimura,H. Sasaki,Z.-X. Chen,M. Ando,M. Nagasawa,H. Mitsuhashi 한국식품과학회 1999 심포지엄 Vol.1999 No.1