SEARCH FOR PULSED γ-RAY EMISSION FROM GLOBULAR CLUSTER M28

Wu, J. H. K.,Hui, C. Y.,Wu, E. M. H.,Kong, A. K. H.,Huang, R. H. H.,Tam, P. H. T.,Takata, J.,Cheng, K. S. IOP Publishing 2013 ASTROPHYSICAL JOURNAL LETTERS - Vol.765 No.2

<P>Using the data from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope, we have searched for gamma-ray pulsations from the direction of the globular cluster M28 (NGC 6626). We report the discovery of a signal with a frequency consistent with that of the energetic millisecond pulsar (MSP) PSR B1821-24 in M28. A weighted H-test test statistic of 28.8 is attained, which corresponds to a chance probability of similar to 10(-5) (4.3 sigma detection). With a phase-resolved analysis, the pulsed component is found to contribute similar to 25% of the total observed gamma-ray emission from the cluster. However, the unpulsed level provides a constraint for the underlying MSP population and the fundamental plane relations for the scenario of inverse Compton scattering. Follow-up timing observations in radio/X-ray are encouraged to further investigate this periodic signal candidate.</P>

Effects of Different Fatty Acids and Levels on the Lipogenesis Capacity and Lipolysis Rate of Broilers In Vitro

Lien, T.F.,Wu, C.P.,Chen, K.L.,Yang, K.H. Asian Australasian Association of Animal Productio 2000 Animal Bioscience Vol.13 No.9

This study investigated the lipogenesis capacity of hepatocytes and lipolysis rate of adipocytes of broilers as affected by different fatty acids (trial one) and different linoleic acid (C18:2) levels (trial two). Twenty 6-wk old broilers were used; their hepatocytes and adipocytes were isolated for the in vitro study. In trial one, four treatments were tested. The control group in which no fatty acid was added, and the test groups to which were added $300{\mu}M$ of C16:0, C18:1 and C18:2, respectively. For trial two, different levels (0, $300{\mu}M$ and 1 mM) of C18:2 combined to fatty acid-free bovine serum albumin (BSA) were added to the medium. According to results of trial one, added fatty acids significantly reduced the incorporation by hepatocytes of [U,$^{14}C$]glucose into total lipid (p<0.05); the lipogenesis capacity in C18:2 group was the lowest. Although a similar pattern was found with [l,$^{14}C$]acetate, the groups only slightly differed in terms of lipogenesis capacity (p=0.11). In addition, the C18:2 group had a significantly (p<0.05) greater lipolysis rate than the C16:0 and control groups. Results of trial two indicated that C18:2 significantly (p<0.05) reduced lipogenesis capacity both for [U,$^{14}C$]glucose and [l,$^{14}C$]acetate, and markedly stimulated the lipolysis rate (p<0.05), displaying a dose response. Results presented herein demonstrate that C18:2 can reduce lipogenesis capacity and stimulate the lipolysis rate in broilers.

Distribution of stress state in the Nankai subduction zone, southwest Japan and a comparison with Japan Trench

Lin, W.,Byrne, T.B.,Kinoshita, M.,McNeill, L.C.,Chang, C.,Lewis, J.C.,Yamamoto, Y.,Saffer, D.M.,Casey Moore, J.,Wu, H.Y.,Tsuji, T.,Yamada, Y.,Conin, M.,Saito, S.,Ito, T.,Tobin, H.J.,Kimura, G.,Kanagaw Elsevier Scientific Publishing Co 2016 Tectonophysics Vol.692 No.2

<P>To better understand the distribution of three dimensional stress states in the Nankai subduction zone, southwest Japan, we review various stress-related investigations carried out in the first and second stage expeditions of the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) by the Integrated Ocean Drilling Program (IODP) and compile the stress data. Overall, the maximum principal stress sigma(l) in the shallower levels (<similar to 1 km) is vertical from near the center of forearc basin to near the trench and; the maximum horizontal stress S-Hmax (interpreted to be the intermediate principal stress sigma(2)) is generally parallel to the plate convergence vector. The exception to this generalization occurs along the shelf edge of the Nankai margin where S-Hmax, is along strike rather than parallel to the plate convergence vector. Reorientation of the principal stresses at deeper levels (e.g., >similar to 1 km below seafloor or in underlying accretionary prism) with sigma(1) becoming horizontal is also suggested at all deeper drilling sites. We also make a comparison of the stress state in the hanging wall of the frontal plate-interface between Site C0066 in the Nankai and Site C0019 in the Japan Trench subduction zone drilled after the 2011 Mw 9.0 Tohoku-Oki earthquake. In the Japan Trench, a comparison between stress state before and after the 2011 mega-earthquake shows that the stress changed from compression before the earthquake to extension after the earthquake. As a result of the comparison between the Nankai Trough and Japan Trench, a similar current stress state with trench parallel extension was recognized at both C0006 and C0019 sites. Hypothetically, this may indicate that in Nankai Trough it is still in an early stage of the interseismic cycle of a great earthquake which occurs on the decollement and propagates to the toe (around site C0006). (C) 2015 Elsevier B.V. All rights reserved.</P>

Study of the dry methane reforming process using a rotating gliding arc reactor

Wu, A.,Yan, J.,Zhang, H.,Zhang, M.,Du, C.,Li, X. Pergamon Press 2014 International journal of hydrogen energy Vol.39 No.31

Dry methane reforming (DMR) via rotating gliding arc (RGA) discharge, co-driven by a magnetic field and tangential flow, was investigated in this study. Optical emission spectroscopy (OES) was used to characterize the major active species (energetic electrons, radicals, ions, atoms and excited molecules) in the DMR chemical process. The influence of the operational conditions (applied voltage and CH<SUB>4</SUB>/CO<SUB>2</SUB> ratio) on the basic spectroscopic parameters (electron excitation temperature, electron density and rotational temperature) was determined by spectroscopic methods. The rotational and electron excitation temperatures were approximately 1100-1200 K and 1.1-1.7 eV, respectively, indicating the non-thermal equilibrium characteristics of the RGA discharge. The electron density was approximately 5-20 x 10<SUP>21</SUP> m<SUP>-3</SUP> by fitting the line shape of H<SUB>α</SUB> at 656 nm. The conversions of the reactants (CH<SUB>4</SUB> and CO<SUB>2</SUB>) and the selectivities of the products (H<SUB>2</SUB>, CO and C<SUB>2</SUB> hydrocarbon) were analyzed using a gas chromatograph (GC) under different energy inputs or feed gas proportions. The structure and morphology of carbon black produced during the chemical process was characterized by high-resolution transmission electron microscopy (HRTEM) and Raman spectroscopy, indicating the properties of electrical conductivity and high absorption capacity that can be useful for potential application.

Functional effects of β₃-adrenoceptor on pacemaker activity in interstitial cells of Cajal from the mouse colon

Wu, M.J.,Shin, D.H.,Kim, M.Y.,Park, C.G.,Kim, Y.D.,Lee, J.,Park, I.K.,Choi, S.,So, I.,Park, J.S.,Jun, J.Y. North-Holland ; Elsevier Science Ltd 2015 european journal of pharmacology Vol.754 No.-

<P>We investigated the presence of beta(3)-adrenoceptor and its functional effects on pacemaker potentials in colonic interstitial cells of Cajal (ICCs) from mice. The whole cell patch clamp technique was used to record pacemaker potentials in cultured ICCs and reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the mRNA transcript levels beta-adrenoceptors. The beta(3)-adrenoceptor agonist, BRL37344, reduced the frequency of pacemaker potentials in a Concentration dependent manner. The inhibitory effects of BRL37344 wore blocked by the pretreatment of propranolol, a nonspecific beta-adrenoceptor antagonist, but not by the selective beta(1)-adrenoceptor antagonist atenolol and the selective beta(2)-adrenoceptor antagonist butoxamine. beta(3)-adrenocepto antagonists SR59230A and L748337 blocked the inhibitory effects of BRL37344. RT-PCR revealed mRNA transcripts of beta(1)- and beta(3)-adrenoceptor, but not beta(2)-adrenoceptor, in c-kit- and Ano-1-positive colonic ICCs. The K+ channel blockers tetraethylammoniu, apamin, and glibenclamide did not block the effects of BRL37344. N-omega-Nitio-L-arginiue methyl ester hydrochloride (L-NAME), an NO synthase inhibitor, and chelerythrine, a protein Kinase C inhibitor, also did not block the effects of BRL37344. Noradrenaline mimicked the effects of BRL37344 in colonic ICCs. However, the inhibitory effects of noradrenaline on pacemaker potentials were blocked only by pretreatment with atenolol but not by butoxamine, SR59230A, or L748337 in small intestinal ICCs, BRL37344 had no effect On pacemaker potentials and mRNA transcripts of beta(1)-and beta(2)-adrenoceptor, but not beta(3)-adrenoceptor were detected. These results suggest that beta(3)-adrenoceptors are present in colonic ICCs and may play a role in regulating gastrointestinal motility by the inhibition or pacemaker potentials. (C) 2015 Elsevier By. All rights reserved.</P>

Optical Characterization of ZnMnO Thin Films on c-Al2O3

H. J. LIN,D. Y. Lin,J. S. Wu,W. C. CHOU,C. S. YANG,J. S. WANG,W. H. Lo 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.1

Various optical measurement technologies have ben used to characterize ZnMnO thin filmswith different Mn compositions grown by molecular beam epitaxy(MBE) on c-Al2O3 substrates. Thelat- tice constant and the crystalization quality have ben evaluated by using X-ray diraction (XRD). Photoluminescence (PL) has ben used to reveal the neutral-donor-bound exciton (D0X) and to checkthelm'squality. Defect-relatedabsorptionsignatures,inadditiontonear-band-edgeabsorp- tion, due to the zinc vacancy and the donor-aceptor pair (DAP) have ben found in the surface photovoltagespectra(SPS).Freexcitonictransitionsandtheirphonon-asistedreplicashaveben observed in the re ectance spectra. Our experimental results not only unveil specic optical tran- sitionenergies but also indicate arapid materiald deterioration whenMn incorporation goes beyond a certain amount to cause manganese segregation. Various optical measurement technologies have ben used to characterize ZnMnO thin filmswith different Mn compositions grown by molecular beam epitaxy(MBE) on c-Al2O3 substrates. Thelat- tice constant and the crystalization quality have ben evaluated by using X-ray diraction (XRD). Photoluminescence (PL) has ben used to reveal the neutral-donor-bound exciton (D0X) and to checkthelm'squality. Defect-relatedabsorptionsignatures,inadditiontonear-band-edgeabsorp- tion, due to the zinc vacancy and the donor-aceptor pair (DAP) have ben found in the surface photovoltagespectra(SPS).Freexcitonictransitionsandtheirphonon-asistedreplicashaveben observed in the re ectance spectra. Our experimental results not only unveil specic optical tran- sitionenergies but also indicate arapid materiald deterioration whenMn incorporation goes beyond a certain amount to cause manganese segregation.

Effects of deposition parameters on the structure and mechanical properties of high-entropy alloy nitride films

T.H. Hsieh,C.H. Hsu,C.Y. Wu,J.Y. Kao,C.Y. Hsu 한국물리학회 2018 Current Applied Physics Vol.18 No.5

High-entropy alloy (AlCrNbSiTiV)N nitride films are prepared using direct current (dc) reactive magnetron sputtering, with an equiatomic AlCrNbSiTiV alloy target. Experiments using the grey-Taguchi method are conducted to determine the effect of deposition parameters (dc power, substrate temperature, N2/(N2+Ar) flow rate and substrate bias) on the microstructure, mechanical and tribological properties. Orthogonal array (L9 34), signal-to-noise ratio and analysis of variance are used to analyze the effect of the deposition parameters. The coated films are examined using scanning electron microscopy, an atomic force microscope, transmission electron microscopy (TEM), a tribometer and a nanoindenter. The TEM patterns confirm that the (AlCrNbSiTiV)N nitride films have a simple face-center-cubic structure. The experimental results show that a (AlCrNbSiTiV)N film coating significantly improves the mechanical properties. In the confirmation runs, using grey relational analysis, the improvement in friction coefficient is 32.5%, in corrosion current is 28.6%, in hardness H is 29.4%, in elastic modulus E is −18.3%, in H/E is 57.1 and in H3/E2 is 225.0%. The samples with (AlCrNbSiTiV)N film coating are classified as HF1 and exhibit good adhesive strength.

Real-time Tumor Oxygenation Changes After Single High-dose Radiation Therapy in Orthotopic and Subcutaneous Lung Cancer in Mice: Clinical Implication for Stereotactic Ablative Radiation Therapy Schedule Optimization

Song, C.,Hong, B.J.,Bok, S.,Lee, C.J.,Kim, Y.E.,Jeon, S.R.,Wu, H.G.,Lee, Y.S.,Cheon, G.J.,Paeng, J.C.,Carlson, D.J.,Kim, H.J.,Ahn, G.O. Pergamon Press 2016 International journal of radiation oncology, biolo Vol.95 No.3

<P>Purpose: To investigate the serial changes of tumor hypoxia in response to single high-dose irradiation by various clinical and preclinical methods to propose an optimal fractionation schedule for stereotactic ablative radiation therapy. Methods and Materials: Syngeneic Lewis lung carcinomas were grown either orthotopically or subcutaneously in C57BL/6 mice and irradiated with a single dose of 15 Gy to mimic stereotactic ablative radiation therapy used in the clinic. Serial [F-18]-misonidazole (F-MISO) positron emission tomography (PET) imaging, pimonidazole fluorescence-activated cell sorting analyses, hypoxia-responsive element-driven bioluminescence, and Hoechst 33342 perfusion were performed before irradiation (day -1), at 6 hours (day 0), and 2 (day 2) and 6 (day 6) days after irradiation for both subcutaneous and orthotopic lung tumors. For F-MISO, the tumor/brain ratio was analyzed. Results: Hypoxic signals were too low to quantitate for orthotopic tumors using F-MISO PET or hypoxia-responsive element-driven bioluminescence imaging. In subcutaneous tumors, the maximum tumor/brain ratio was 2.87 +/- 0.483 at day -1, 1.67 +/- 0.116 at day 0, 2.92 +/- 0.334 at day 2, and 2.13 +/- 0.385 at day 6, indicating that tumor hypoxia was decreased immediately after irradiation and had returned to the pretreatment levels at day 2, followed by a slight decrease by day 6 after radiation. Pimonidazole analysis also revealed similar patterns. Using Hoechst 33342 vascular perfusion dye, CD31, and cleaved caspase 3 coimmunostaining, we found a rapid and transient vascular collapse, which might have resulted in poor intratumor perfusion of F-MISO PET tracer or pimonidazole delivered at day 0, leading to decreased hypoxic signals at day 0 by PET or pimonidazole analyses. Conclusions: We found tumor hypoxia levels decreased immediately after delivery of a single dose of 15 Gy and had returned to the pretreatment levels 2 days after irradiation and had decreased slightly by day 6. Our results indicate that single high-dose irradiation can produce a rapid, but reversible, vascular collapse in tumors. (C) 2016 Elsevier Inc. All rights reserved.</P>

A two-photon fluorescent probe for specific detection of hydrogen sulfide based on a familiar ESIPT fluorophore bearing AIE characteristics

Chen, L.,Wu, D.,Lim, C.,Kim, D.,Nam, S. J.,Lee, W.,Kim, G.,Kim, H.,Yoon, J. unknown 2017 Chemical communications Vol. No.

<P>Hydrogen sulfide (H2S) is a signaling gasotransmitter, which plays various roles in modulating the functions of different systems. In this study, a 'turn-on'' fluorescent probe for H2S was developed. The probe, whose design is based on a familiar excited state intramolecular proton transfer (ESIPT) fluorophore bearing aggregation-induced emission (AIE) characteristics, was found to exhibit an 80-fold fluorescence enhancement along with a large Stokes shift upon the addition of H2S. Furthermore, the probe was successfully utilized to detect H2S in HeLa cells with both one-photon and two-photon microscopy.</P>

Hexacosanol reduces plasma and hepatic cholesterol by activation of AMP-activated protein kinase and suppression of sterol regulatory element-binding protein-2 in HepG2 and C57BL/6J mice

Lee, J.H.,Jia, Y.,Thach, T.T.,Han, Y.,Kim, B.,Wu, C.,Kim, Y.,Seo, W.D.,Lee, S.J. Pergamon Press 2017 Nutrition research Vol.43 No.-

<P>Policosanols have hypocholesterolemic activity; however, the molecular mechanism of the policosanol effects is currently poorly characterized. We hypothesized that hexacosanol, a policosanol compound derived from barley sprout, may decrease cellular and plasma cholesterol levels; we thus investigated the hypocholesterolemic activity and mechanism of hexacosanol on both hepatocytes and high-fat-induced obese C57BL/6J mice. The reduction of total cholesterol, free cholesterol, and cholesteryl ester concentrations was confirmed in hexacosanol-stimulated hepatocytes (-38%, -33%, and -53%, respectively). Plasma, hepatic cholesterol concentrations, and hepatic steatosis were significantly reduced in high-fat-fed mice orally administered with hexacosanol (0.7 mg/kg body weight a day) for 8 weeks compared with those of vehicle-fed control mice (-15% and -40%, respectively). Hexacosanol in fact bound to the allosteric regulation site of AMP-activated protein kinase (AMPK)-beta subunit and thus activated AMPK that inhibited the activity of 3-hydroxy-3methyl-glutaryl-coenzyme A reductase by inhibitory phosphorylation. In addition, activation of AMPK by hexacosanol induced hepatic autophagy activity, which could further reduce hepatic lipid accumulation. Alternatively, hexacosanol suppressed the nuclear translocation and activation of sterol regulatory element-binding protein-2 (SREBP-2), a key transcription factor in cholesterol biosynthesis. These results collectively suggest that hexacosanol is a major hypocholesterolemic compound in barley sprouts with regulation of AMPK activation and SREBP-2 suppression. These suppress 3-hydroxy-3-methyl-glutarylcoenzyme A reductase at both mRNA expression and protein activity levels. In conclusion, hexacosanol activates AMPK and hepatic autophagy and inhibits SREBP2, resulting in hypocholesterolemic activities and improvement of hepatic steatosis. (C) 2017 Published by Elsevier Inc.</P>