CANDELS Sheds Light on the Environmental Quenching of Low-mass Galaxies

Guo, Yicheng,Bell, Eric F.,Lu, Yu,Koo, David C.,Faber, S. M.,Koekemoer, Anton M.,Kurczynski, Peter,Lee, Seong-Kook,Papovich, Casey,Chen, Zhu,Dekel, Avishai,Ferguson, Henry C.,Fontana, Adriano,Giavalis American Astronomical Society 2017 ASTROPHYSICAL JOURNAL LETTERS - Vol.841 No.2

<P>We investigate the environmental quenching of galaxies, especially those with stellar masses (M-*) < 10(9.5) Me-circle dot, beyond the local universe. Essentially all local low-mass quenched galaxies (QGs) are believed to live close to massive central galaxies, which is a demonstration of environmental quenching. We use CANDELS data to test whether or not such a dwarf QG-massive central galaxy connection exists beyond the local universe. For this purpose, we only need a statistically representative, rather than complete, sample of low-mass galaxies, which enables our study to z greater than or similar to 1.5. For each low-mass galaxy, we measure the projected distance (d(proj)) to its nearest massive neighbor (M-* > 10(10.5) M-circle dot) within a redshift range. At a given z and M-*, the environmental quenching effect is considered to be observed if the d(proj) distribution of QGs (d(proj)(Q)) is significantly skewed toward lower values than that of star-forming galaxies (d(proj)(SF)). For galaxies with 10(8) M-circle dot < M-* < 10(10) M-circle dot, such a difference between d(proj)(Q) and d(proj)(SF) is detected up to z similar to 1. Also, about 10% of the quenched galaxies in our sample are located between two and four virial radii (R-Vir) of the massive halos. The median projected distance from low-mass QGs to their massive neighbors, d(proj)(Q)/R-Vir, decreases with satellite M-* at M-* less than or similar to 10(9.5) M-circle dot, but increases with satellite M-* at M-* greater than or similar to 10(9.5) M-circle dot. This trend suggests a smooth, if any, transition of the quenching timescale around M-* similar to 10(9.5) M-circle dot at 0.5 < z < 1.0.</P>

FORTRAN Program "PHYLS" for the Geometrical prediction of the Structures of 1M and 2M_(1) 2:1 Phyllosilicates Having Space Groups C2/m, C2, and C2/c

Yu, Jae-Young,M. Slaughter 江原大學校 附設 環境硏究所 1998 環境硏究 Vol.15 No.-

기학학적 분석을 바탕으로 1M 및 2N_(1) 2:1 층상 규산염 광물의 구조를 모델링 하기위한 포트란 프로그램 PHYLS가 개발 되었다. PHYLS를 수행사기 위한 입력자료는 광물의 하학 조성과 d(001) 격자 거리며 , 이로부터의 출력은 단위포 내 결정학적 독립 구조 자리의 위치 그리고 단위포의 크기 및 부피, 측각, 원자간 거리 다면체의 변셩각도등을 포함하는 구조적 요소들이다. PHYLS는 이와 같은 자세한 구조 정보를 사용자가 선택하는 고간군 FORTRAN program PHYLS was developed to model the structures of 2:1 IM and 2M_(1) phyllosilicates on the basis of geometrical analyses. Input to PHYLS requires the chemical composition and d(001) spacing of the mineral The output from PHYLS consists of the coordinates of the orystallosraphicallyindependent sites in the unit cell, and such structural parameters as the cell dimensions, interaxial angle. cell volume, interatomic distances, and deformation angles of the polyhedra. PHYLS can generate these structural details according to the user's choice of space group and cation configuration. User can choose one of such space groups as C2/m, C2. and C2/c and such cation configurations as random and ordered fetrahedral/octahedral cation configurations . PHYLS simulated the structures of dioctahedral and trioctahedral phyllosilicates having random tetrahedral cation configuration fairIy close to the reported experimentally determined structures. In contrast, the simulated structures for ordered tetrahedral cation configurations showed greater deviation from the experimentally determined structures than those for random configurations. However, if the cations were partially ordered and the sizes of the tetrahedra became similar, the simulated structures showed little deviations from the experimental ones, which suggests that appropriate application of PHYLS may be helpful in various investigations on the relationships between structures and Physicochemical Properties of the phyllosilicates.

Enhanced dechlorination of m-DCB using ironχraphite/palladium (FeΓ/Pd) nanoparticles produced by pulsed laser ablation in liquid

Yu, Y.,Jung, H.J.,Je, M.,Choi, H.C.,Choi, M.Y. Pergamon Press 2016 CHEMOSPHERE - Vol.155 No.-

In this work, the zero valent Fe (ZVI) and graphite-encapsulated Fe (FeΓ) nanoparticles (NPs) were easily and selectively prepared by a pulsed laser ablation (PLA) method in an aqueous sodium borohydride solution and ascorbic acid dissolved in methanol, respectively. Here, the FeΓ NPs were uniquely synthesized by PLA in methanol, where the solvent is used as both a carbon source for the graphitic layers and solvent, which is very unique. Furthermore, Pd NPs were loaded onto the surface of the FeΓ NPs to prepare bimetallic (FeΓ/Pd) NPs for the enhancement of the degradation efficiency of m-dichlorobenzene (m-DCB). The morphology, crystallinity, and surface composition of the prepared NPs were carefully characterized by high-resolution transmission electron microscopy (HRTEM), energy dispersive x-ray spectrometer (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The degradation rate of m-DCB using single (Fe and Pd) or bimetallic (Fe/Pd and FeΓ/Pd) NPs were compared by using gas chromatography. Among these NPs produced in this work, the FeΓ/Pd NPs with 1.71 wt % of Pd showed an excellent dechlorination efficiency for m-DCB with 100% degradation within 75 min. The graphitic layer on the Fe NPs played as not only an oxidation resistant for the Fe NPs to surroundings, but also a supporter of the Pd NPs for the enhanced degradation efficiency of m-DCB.

Role of flotillins in the endocytosis of GPCR in salivary gland epithelial cells

Park, M.Y.,Kim, N.,Wu, L.L.,Yu, G.Y.,Park, K. Academic Press 2016 Biochemical and biophysical research communication Vol.476 No.4

Endocytosis has numerous functions in cellular homeostasis. Defects in the endocytic pathway of receptors may lead to dysfunction of salivary gland secretion. Therefore, elucidating the complex mechanisms of endocytosis may facilitate solutions for disease treatment and prevention. The muscarinic type 3 receptor (M3R), a G-protein-coupled receptor (GPCR) located in the plasma membrane, is involved in numerous physiological activities such as smooth muscle contraction and saliva secretion. M3R enters cells through clathrin-mediated endocytosis (CME), while flotillins (flot-1 and -2), highly conserved proteins residing in lipid-raft microdomains, make use of clathrin-independent endocytosis (CIE) for their internalization. Since these two proteins use two discrete pathways for endocytic entry, the association of flotillins with CME is poorly understood. We examined whether flotillins play a role in CME of M3R using immunoblotting, immunocytochemistry, confocal immunofluorescence microscopy, co-immunoprecipitation, and RNA interference techniques in secretory epithelial cells. Upon stimulation with a cholinergic agonist, M3R, flot-1, and flot-2 each internalized from the plasma membrane into intracellular sites. The addition of chlorpromazine and cytochalasin D, well-known inhibitors of CME, inhibited internalization of M3R via CME. Filipin III and methyl-β-cyclodextrin (mβCD) acting as lipid raft inhibitors disrupted internalization of flot-½ via CIE. Interestingly, filipin III and mβCD slightly reduced expression level of M3R whereas chlorpromazine and cytochalasin D did not affect internalization of the flotillin isoforms. M3R and flot-½ colocalized and interacted with each other as they entered the cytosol during limited periods of incubation. Moreover, knockdown of flot-1 or -2 by flotillin-specific siRNA prevented internalization and reduced the endocytic efficiency of M3R. Our results suggest that flot-1 and -2 are partially involved in CME of M3R by facilitating its internalization.

THE EVOLUTION OF THE GALAXY STELLAR MASS FUNCTION AT<i>z</i>= 4-8: A STEEPENING LOW-MASS-END SLOPE WITH INCREASING REDSHIFT

Song, Mimi,Finkelstein, Steven L.,Ashby, Matthew L. N.,Grazian, A.,Lu, Yu,Papovich, Casey,Salmon, Brett,Somerville, Rachel S.,Dickinson, Mark,Duncan, K.,Faber, Sandy M.,Fazio, Giovanni G.,Ferguson, He American Astronomical Society 2016 The Astrophysical Journal Vol.825 No.1

<P>We present galaxy stellar mass functions (GSMFs) at z = 4-8 from a rest-frame ultraviolet (UV) selected sample of similar to 4500 galaxies, found via photometric redshifts over an area of similar to 280 arcmin(2) in the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS)/Great Observatories Origins Deep Survey (GOODS) fields and the Hubble Ultra Deep Field. The deepest Spitzer/IRAC data to date and the relatively large volume allow us to place a better constraint at both the low- and high-mass ends of the GSMFs compared to previous space-based studies from pre-CANDELS observations. Supplemented by a stacking analysis, we find a linear correlation between the rest-frame UV absolute magnitude at 1500 angstrom (M-UV) and logarithmic stellar mass (log M-*) that holds for galaxies with log(M-*/M-circle dot) less than or similar to 10. We use simulations to validate our method of measuring the slope of the log M-*-M-UV relation, finding that the bias is minimized with a hybrid technique combining photometry of individual bright galaxies with stacked photometry for faint galaxies. The resultant measured slopes do not significantly evolve over z = 4-8, while the normalization of the trend exhibits a weak evolution toward lower masses at higher redshift. We combine the log M-*-M-UV distribution with observed rest-frame UV luminosity functions at each redshift to derive the GSMFs, finding that the low-mass-end slope becomes steeper with increasing redshift from alpha = -1.55(-0.07)(+0.08) at z = 4 to alpha = -2.25(-0.35)(+0.72) at z = 8. The inferred stellar mass density, when integrated over M-* = 10(8)-10(13) M-circle dot, increases by a factor of 10(-2)(+30) between z = 7 and z = 4 and is in good agreement with the time integral of the cosmic star formation rate density.</P>

Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis

Yu, K‐,H.,Hong, K‐,S.,Lee, B‐,C.,Oh, M‐,S.,Cho, Y‐,J.,Koo, J‐,S.,Park, J‐,M.,Bae, H‐,J.,Han, M‐,K.,Ju, Y‐,S.,Kang, D‐,W.,Appelros, P. Blackwell Publishing Ltd 2011 Acta neurologica Scandinavica Vol.123 No.5

<P>Yu K‐H, Hong K‐S, Lee B‐C, Oh M‐S, Cho Y‐J, Koo J‐S, Park J‐M, Bae H‐J, Han M‐K, Ju Y‐S, Kang D‐W, Appelros P, Norrving B, Terent A. Comparison of 90‐day case‐fatality after ischemic stroke between two different stroke outcome registries using propensity score matching analysis. 
Acta Neurol Scand: 2011: 123: 325–331. 
© 2010 John Wiley & Sons A/S.</P><P><B>Background – </B> It has not been clarified whether the disparity in ischemic stroke outcome between populations is caused by ethnic and geographic differences or by variations in case mix. Propensity score matching (PSM) analysis can overcome some analytical problems but is rarely used in stroke outcome research. This study was to compare the ischemic stroke case‐fatality between two PSM cohorts of Sweden and Korea.</P><P><B>Methods – </B> Prognostic variables related to baseline characteristics and stroke care were included in our PSM model. Then, we selected 7675 Swedish and 1220 Korean patients with ischemic stroke from each stroke registers and performed one‐to‐one matching based on propensity scores of each patient.</P><P><B>Results – </B> After PSM, all measured variables were well balanced in 1163 matched subjects, and the 90‐day case‐fatality was identical 6.2% (HR 0.997, 95%CI 0.905–1.099) in Sweden and Korea.</P><P><B>Conclusions – </B> No difference is found in the 90‐day case‐fatality in propensity score‐matched Swedish and Korean patients with ischemic stroke.</P>

Metal-organic frameworks as efficient catalytic systems for the synthesis of 1,5-benzodiazepines from 1,2-phenylenediamine and ketones

Timofeeva, M.N.,Panchenko, V.N.,Prikhod'ko, S.A.,Ayupov, A.B.,Larichev, Yu.V.,Khan, Nazmul Abedin,Jhung, Sung Hwa Academic Press 2017 Journal of catalysis Vol.354 No.-

<P><B>Abstract</B></P> <P>Benzodiazepines and their derivatives are a very important class of nitrogen-containing heterocyclic compounds with biological activity that are widely used in medicine. In this study, we demonstrated synthesis of 1,5-benzodiazepines from 1,2-phenylenediamine and ketones (acetone, cyclohexanone, acetophenone, methyl ethyl ketone) in the presence of isostructural porous metal-benzenetricarboxylates of the families MIL-100(M) (M: V<SUP>3+</SUP>, Al<SUP>3+</SUP>, Fe<SUP>3+</SUP> and Cr<SUP>3+</SUP>) and three porous aluminium trimesates Al-BTCs (MIL-96(Al), MIL-100(Al) and MIL-110(Al)). A combination of catalytic, theoretical and physicochemical methods showed that reaction rates and yields of 1,5-benzodiazepines were adjusted by the type of metal ions and accessibility of active sites. The yield of 1,5-benzodiazepines in the presence of MIL-100(M) was comparable with zeolites, such as HY, H-ZSM−5, β-zeolite and heulandite.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of 1,5-benzodiazepines over MIL-100(M), MIL-110 and MIL-96 was studied. </LI> <LI> Effect of Brønsted and Lewis acidity on MIL’s performance was investigated. </LI> <LI> Lewis acidity of MIL-100(Fe, Cr, Al, V) was studied by EPR spectroscopy. </LI> <LI> The type of M<SUP>3+</SUP>(Al, Fe, Cr, V) and structure of MILs affect the yield of product. </LI> <LI> MIL-100(M) samples perform well in compared with zeolites. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

New self-activated eulytite-type compounds of M₇Zr(PO₄)₆ (M=Ca, Sr, Ba)

Qin, L.,Wei, D.,Huang, Y.,Kim, S.I.,Yu, Y.M.,Seo, H.J. Elsevier Sequoia 2013 Journal of alloys and compounds Vol.574 No.-

Eulytite-type orthophosphates M<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>6</SUB> (M=Ca, Sr, Ba) were prepared by conventional high temperature solid-state reaction. Sr<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>6</SUB> and Ba<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>6</SUB> crystallize in the pure eulytite-type phase with cubic space group (I4@?3d). The impurity phase β-Ca<SUB>3</SUB>(PO<SUB>4</SUB>)<SUB>2</SUB> was inevitably coexisted with the Ca<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>6</SUB> phase. The luminescence properties are investigated by UV-VUV excitation and emission spectroscopy and X-ray-excited luminescence (XEL) spectroscopy. The broad excitation and emission bands are observed due to the charge transfer transition from Zr<SUP>4+</SUP> to O<SUP>2-</SUP> in M<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>6</SUB> (M=Ca, Sr, Ba) eulytite. The characteristics of the phosphors including the luminescence mechanism are explained by Stokes shift, decay curves, and CIE color coordinates. The Sr<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>3</SUB> and Ba<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>3</SUB> phosphors exhibit unusual spectral features with the emission bands at 470 and 480nm, respectively. The weak luminescence centered at 495nm is observed in the Ca<SUB>7</SUB>Zr(PO<SUB>4</SUB>)<SUB>6</SUB> eulytite with lifetime of 4.67μs. The unusual self-activated luminescence is discussed on the base of the crystal structure of eulytite.

Nonlinear optical properties of mushroom-shaped CdSe/CdS coreshells.

Ma, S M,Seo, J T,Yu, W,Yang, Q,Tabibi, B,Temple, D,Namkung, M,Heo, J,Kim, W J,Jung, S S American Scientific Publishers 2009 Journal of nanoscience and nanotechnology Vol.9 No.2

<P>The third-order nonlinear optical susceptibilities of mushroom-shaped CdSe/CdS coreshells as a function of concentration have been investigated using polarization- and concentration-resolved degenerate four-wave mixing in a resonant region. The effective third-order nonlinear optical susceptibilities, /chi(3)xxxx/ and /chi(3)xyyx/ of CdSe/CdS coreshells were estimated to be approximately 1.86 x 10(-21)-1.03 x 10(-20) m2/V2, and approximately 0.45 x 10(-21)-6.15 x 10(-21) m2/V2, respectively, for various concentrations of approximately 0.64 x 10(-3)-4.95 x 10(-3) mol/m3. The second hyperpolarizabilities, /<gammah>xxxx/ and /<gammah>xyyx/, of CdSe/CdS coreshells were extracted to be approximately 2.37 x 10(-41) m5/V2 and approximately 1.29 x 10(-41) m5/V2, respectively.</P>

Characterization of Nutritional Value for Twenty-one Pork Muscles

Kim, J.H.,Seong, P.N.,Cho, S.H.,Park, B.Y.,Hah, K.H.,Yu, L. H.,Lim, D.G.,Hwang, I.H.,Kim, D.H.,Lee, J.M.,Ahn, C.N. Asian Australasian Association of Animal Productio 2008 Animal Bioscience Vol.21 No.1

A study was conducted to evaluate nutritional value for twenty-one pork muscles. Ten market-weight crossbred pigs (five gilts and five barrows) were used for evaluating proximate chemical composition, cholesterol, total iron, calorie and fatty acid contents. As preliminary analysis revealed no noticeable sex effect, pooled data from both sexes were used for the final analysis. M. rectus femoris had the highest moisture content, while m. latissimus dorsi was lowest in moisture content (p<0.05). Protein content was highest for m. longissimus dorsi and lowest for m. supraspinatus (p<0.05). The tensor fasciae and latissimus dorsi muscles contained the highest intramuscular fat (p<0.05), while rectus femoris, adductor and vastus lateralis were lowest in intramuscular fat content. When simple correlations between chemical values were computed for the pooled dataset from all muscles, intramuscular fat had significant (p<0.05) negative linear relationships with moisture (r = -0.85) and protein (r = -0.51) contents. Calorie levels were not significantly affected by fat content, while rectus femoris and latissimus dorsi muscles showed lowest and highest calorie contents, respectively (p<0.05). Polyunsaturated fatty acid content was highest (p<0.05) for both m. adductor and m. rectus femoris, while it was lowest for m. longissimus dorsi. Collectively, the current study identified a large amount of variation in nutritional characteristics between pork muscles, and the data can be used for the development of muscle-specific strategies to improve eating quality of meats and meat products.