<i>FERMI</i> -LAT DETECTION OF PULSED GAMMA-RAYS ABOVE 50 GeV FROM THE VELA PULSAR

Leung, Gene C. K.,Takata, J.,Ng, C. W.,Kong, A. K. H.,Tam, P. H. T.,Hui, C. Y.,Cheng, K. S. IOP Publishing 2014 ASTROPHYSICAL JOURNAL LETTERS - Vol.797 No.2

<P>The first Fermi-Large Area Telescope (LAT) catalog of sources above 10 GeV reported evidence of pulsed emission above 25 GeV from 12 pulsars, including the Vela pulsar, which showed evidence of pulsation at > 37 GeV energy bands. Using 62 months of Fermi-LAT data, we analyzed the gamma-ray emission from the Vela pulsar and searched for pulsed emission above 50 GeV. Having confirmed the significance of the pulsation in 30-50 GeV with the H test (p-value similar to 10(-77)), we extracted its pulse profile using the Bayesian block algorithm and compared it with the distribution of the five observed photons above 50 GeV using the likelihood ratio test. Pulsation was significantly detected for photons above 50 GeV with a p-value of = 3 x 10(-5) (4.2 sigma). The detection of pulsation is significant above 4 sigma at > 79 GeV and above 3 sigma at > 90 GeV energy bands, making this the highest energy pulsation significantly detected by the LAT. We explore the non-stationary outer gap scenario of the very high-energy emissions from the Vela pulsar.</P>

Genome-wide association study in a Chinese population identifies a susceptibility locus for type 2 diabetes at 7q32 near <i>PAX4</i>

Ma, R. C. W.,Hu, C.,Tam, C. H.,Zhang, R.,Kwan, P.,Leung, T. F.,Thomas, G. N.,Go, M. J.,Hara, K.,Sim, X.,Ho, J. S. K.,Wang, C.,Li, H.,Lu, L.,Wang, Y.,Li, J. W.,Wang, Y.,Lam, V. K. L.,Wang, J.,Yu, W.,Ki Springer-Verlag 2013 Diabetologia Vol.56 No.6

<P><B>Aims/hypothesis</B></P><P>Most genetic variants identified for type 2 diabetes have been discovered in European populations. We performed genome-wide association studies (GWAS) in a Chinese population with the aim of identifying novel variants for type 2 diabetes in Asians.</P><P><B>Methods</B></P><P>We performed a meta-analysis of three GWAS comprising 684 patients with type 2 diabetes and 955 controls of Southern Han Chinese descent. We followed up the top signals in two independent Southern Han Chinese cohorts (totalling 10,383 cases and 6,974 controls), and performed in silico replication in multiple populations.</P><P><B>Results</B></P><P>We identified <I>CDKN2A/B</I> and four novel type 2 diabetes association signals with <I>p</I> < 1 × 10<SUP>−5</SUP> from the meta-analysis. Thirteen variants within these four loci were followed up in two independent Chinese cohorts, and rs10229583 at 7q32 was found to be associated with type 2 diabetes in a combined analysis of 11,067 cases and 7,929 controls (<I>p</I><SUB>meta</SUB> = 2.6 × 10<SUP>−8</SUP>; OR [95% CI] 1.18 [1.11, 1.25]). In silico replication revealed consistent associations across multiethnic groups, including five East Asian populations (<I>p</I><SUB>meta</SUB> = 2.3 × 10<SUP>−10</SUP>) and a population of European descent (<I>p</I> = 8.6 × 10<SUP>−3</SUP>). The rs10229583 risk variant was associated with elevated fasting plasma glucose, impaired beta cell function in controls, and an earlier age at diagnosis for the cases. The novel variant lies within an islet-selective cluster of open regulatory elements. There was significant heterogeneity of effect between Han Chinese and individuals of European descent, Malaysians and Indians.</P><P><B>Conclusions/interpretation</B></P><P>Our study identifies rs10229583 near <I>PAX4</I> as a novel locus for type 2 diabetes in Chinese and other populations and provides new insights into the pathogenesis of type 2 diabetes.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (doi:10.1007/s00125-013-2874-4) contains peer-reviewed but unedited supplementary material, which is available to authorised users.</P>

HIGH-ENERGY EMISSIONS FROM THE GAMMA-RAY BINARY LS 5039

Takata, J.,Leung, Gene C. K.,Tam, P. H. T.,Kong, A. K. H.,Hui, C. Y.,Cheng, K. S. IOP Publishing 2014 The Astrophysical journal Vol.790 No.1

<P>We study mechanisms of multi-wavelength emissions (X-ray, GeV, and TeV gamma-rays) from the gamma-ray binary LS 5039. This paper is composed of two parts. In the first part, we report on results of observational analysis using 4 yr data of the Fermi Large Area Telescope. Due to the improvement of instrumental response function and increase of the statistics, the observational uncertainties of the spectrum in the similar to 100-300 MeV bands and > 10 GeV bands are significantly improved. The present data analysis suggests that the 0.1-100 GeV emissions from LS 5039 contain three different components: (1) the first component contributes to <1 GeV emissions around superior conjunction, (2) the second component dominates in the 1-10 GeV energy bands, and (3) the third component is compatible with the lower-energy tail of the TeV emissions. In the second part, we develop an emission model to explain the properties of the phase-resolved emissions in multi-wavelength observations. Assuming that LS 5039 includes a pulsar, we argue that emissions from both the magnetospheric outer gap and the inverse-Compton scattering process of cold-relativistic pulsar wind contribute to the observed GeV emissions. We assume that the pulsar is wrapped by two kinds of termination shock: Shock-I due to the interaction between the pulsar wind and the stellar wind and Shock-II due to the effect of the orbital motion. We propose that the X-rays are produced by the synchrotron radiation at the Shock-I region and the TeV gamma-rays are produced by the inverse-Compton scattering process at the Shock-II region.</P>

Simulation of vibrations of Ting Kau Bridge due to vehicular loading from measurements

F.T.K. Au,P. Lou,J. Li,R.J. Jiang,J. Zhang,C.C.Y. Leung,P.K.K. Lee,이진휴,K.Y. Wong,H.Y. Chan 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.4

The Ting Kau Bridge in Hong Kong is a cable-stayed bridge comprising two main spans and two side spans. The bridge deck is supported by three towers, an end pier and an abutment. Each of the three towers consists of a single reinforced concrete mast strengthened by transverse cables and struts. The bridge deck is supported by four inclined planes of cables emanating from anchorages at the tower tops. In view of the heavy traffic on the bridge, and threats from typhoons and earthquakes originated in areas nearby, the dynamic behaviour of long-span cable-supported bridges in the region is always an important consideration in their design. Baseline finite element models of various levels of sophistication have been built not only to match the bridge geometry and cable forces specified on the as-constructed drawings but also to be calibrated using the vibration measurement data captured by the Wind and Structural Health Monitoring System. This paper further describes the analysis of axle loading data, as well as the generation of random axle loads and simulation of vibrations of the bridge using the finite element models. Various factors affecting the vehicular loading on the bridge will also be examined.

Simulation of vibrations of Ting Kau Bridge due to vehicular loading from measurements

Au, F.T.K.,Lou, P.,Li, J.,Jiang, R.J.,Zhang, J.,Leung, C.C.Y.,Lee, P.K.K.,Lee, J.H.,Wong, K.Y.,Chan, H.Y. Techno-Press 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.4

The Ting Kau Bridge in Hong Kong is a cable-stayed bridge comprising two main spans and two side spans. The bridge deck is supported by three towers, an end pier and an abutment. Each of the three towers consists of a single reinforced concrete mast strengthened by transverse cables and struts. The bridge deck is supported by four inclined planes of cables emanating from anchorages at the tower tops. In view of the heavy traffic on the bridge, and threats from typhoons and earthquakes originated in areas nearby, the dynamic behaviour of long-span cable-supported bridges in the region is always an important consideration in their design. Baseline finite element models of various levels of sophistication have been built not only to match the bridge geometry and cable forces specified on the as-constructed drawings but also to be calibrated using the vibration measurement data captured by the Wind and Structural Health Monitoring System. This paper further describes the analysis of axle loading data, as well as the generation of random axle loads and simulation of vibrations of the bridge using the finite element models. Various factors affecting the vehicular loading on the bridge will also be examined.

Field measurements of natural periods of vibration and structural damping of wind-excited tall residential buildings

S. Campbell,K.C.S. Kwok,P.A. Hitchcock,K.T. Tse,H.Y. Leung 한국풍공학회 2007 Wind and Structures, An International Journal (WAS Vol.10 No.5

Field measurements of the wind-induced response of two residential reinforced concrete buildings, among the tallest in the world, have been performed during two typhoons. Natural periods and damping values have been determined and compared with other field measurements and empirical predictors. Suitable and common empirical predictors of natural period and structural damping have been obtained that describe the trend of tall, reinforced concrete buildings whose structural vibrations have been measured in the collection of studies in Hong Kong compiled by the authors. This data is especially important as the amount of information known about the dynamic parameters of buildings of these heights is limited. Effects of the variation of the natural period and damping values on the alongwind response of a tall building for serviceability-level wind conditions have been profiled using the gust response factor approach. When using this approach on these two buildings, the often overestimated natural periods and structural damping values suggested by empirical predictors tended to offset each other. Gust response factors calculated using the natural periods and structural damping values measured in the field were smaller than if calculated using design-stage values.

Field measurements of natural periods of vibration and structural damping of wind-excited tall residential buildings

Campbell, S.,Kwok, K.C.S.,Hitchcock, P.A.,Tse, K.T.,Leung, H.Y. Techno-Press 2007 Wind and Structures, An International Journal (WAS Vol.10 No.5

Field measurements of the wind-induced response of two residential reinforced concrete buildings, among the tallest in the world, have been performed during two typhoons. Natural periods and damping values have been determined and compared with other field measurements and empirical predictors. Suitable and common empirical predictors of natural period and structural damping have been obtained that describe the trend of tall, reinforced concrete buildings whose structural vibrations have been measured in the collection of studies in Hong Kong compiled by the authors. This data is especially important as the amount of information known about the dynamic parameters of buildings of these heights is limited. Effects of the variation of the natural period and damping values on the alongwind response of a tall building for serviceability-level wind conditions have been profiled using the gust response factor approach. When using this approach on these two buildings, the often overestimated natural periods and structural damping values suggested by empirical predictors tended to offset each other. Gust response factors calculated using the natural periods and structural damping values measured in the field were smaller than if calculated using design-stage values.

Patterning of FePt for Magnetic Recording

G.J. Li,C.W. Leung,Z.Q. Lei,K.W. Lin,P.T. Lai,Philip W.T. Pong 한국자기학회 2010 한국자기학회 학술연구발표회 논문개요집 Vol.2010 No.12

Fabrication and Characterization of ALD-grown ZrO2:Ge Thin Films on Si(1 0 0) using CpZr(NMe2 )3 and (NMe2 )2Ge( ipr2en) Precursors with Ozone

정대선,김대현,신진호,강정수,Joseph P. Thomas,K. T. Leung,강준길 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.8

Clinical effectiveness of mindfulness-based music therapy on improving emotional regulation in blind older women: A randomized controlled trial

Sunny H.W. Chan,Meryl Y.C. Cheung,Armstrong T.S. Chiu,Mimi H.T. Leung,Michael C.C. Kuo,Donald Y.C. Yip,Carole C.Y. Hui,Sally W.I. Kam,King Yeung,Doreen S.P. Mui,Shu-Mei Wang,Calvin C.K. Yip 한국한의학연구원 2023 Integrative Medicine Research Vol.12 No.4

Background: This study aimed to investigate clinical effectiveness of a structured eight-week mindfulness-based music therapy (MBMT) program on improving mood regulation in older women with blindness. This investigation compared a MBMT group with a mindfulness intervention (MI) group and a control group. Methods: Ninety-two older females with blindness from a residential setting in Hong Kong were recruited and randomly allocated to a MBMT (n = 31), MI (n = 30), or control (n = 31) group. Psychological measurements regarding mood regulation and general mood states (namely, Difficulties in Emotion Regulation Scale [DERS], Geriatric Depression Scale [GDS], and Depression Anxiety Stress Scales-21), were taken at pretest and posttest. Outcome assessors were blinded to group assignment. Results: Data was analyzed based on intention-to-treat basis. At posttest, DERS scores in the MBMT group (mean differences and 95% confidence interval: 12.1, 5.5 to 18.8) and the MI group (7.2, 0.5 to 13.8) were lower than that in the control group. GDS scores in the MBMT group (2.9, 1.7 to 4.0) and the MI group (1.7, 0.6 to 2.9) were lower than those in the control group. Compared with the MI group, the MBMT group improved emotional awareness sub-scores in DERS (2.1, 0.2 to 4.1) and appeared to lower depression in GDS scores (1.1, -0.0 to 2.3; p = 0.053). Conclusion: MBMT seems more beneficial than MI alone for improving emotional regulation in older women with blindness. The combination of mindfulness and music can generate a synergetic effect by enhancing both attention and appraisal components within the emotional-regulation process. Trial registration: ClinicalTrials.gov, NCT05583695.