미생물학적 검사로 확진된 전신성 Cryptococcus증 1예 보고

박애자,김현태,유재형,전성훈,장세경,김종숙,홍창권 중앙대부설한국의과학연구소 1986 한국의과학 Vol.18 No.1

Kinetic modeling of divertor heat load fluxes in the Alcator C-Mod and DIII-D tokamaks

Pankin, A. Y.,Rafiq, T.,Kritz, A. H.,Park, G. Y.,Chang, C. S.,Brunner, D.,Groebner, R. J.,Hughes, J. W.,LaBombard, B.,Terry, J. L.,Ku, S. American Institute of Physics 2015 Physics of plasmas Vol.22 No.9

Differential Cross Section and Photon-Beam Asymmetry for the γ→p → π−Δ++(1232) Reaction at Forward π− Angles for Eγ=1.5-2.95 GeV

Kohri, H.,Shiu, S. H.,Chang, W. C.,Yanai, Y.,Ahn, D. S.,Ahn, J. K.,Chen, J. Y.,Daté,, S.,Ejiri, H.,Fujimura, H.,Fujiwara, M.,Fukui, S.,Gohn, W.,Hicks, K.,Hosaka, A.,Hotta, T.,Hwang, S. H.,Imai, American Physical Society 2018 Physical Review Letters Vol.120 No.20

<P>Differential cross sections and photon-beam asymmetries for the gamma(->)p -> Pi(-)Delta(++)(1232) reaction have been measured for 0.7 < cos Theta(c.m.)(Pi) < 1 and E-gamma= 1.5-2.95 GeV at SPring-8/LEPS. The first-ever high statistics cross-section data are obtained in this kinematical region, and the asymmetry data for 1.5 < E-gamma(GeV) < 2.8 are obtained for the first time. This reaction has a unique feature for studying the production mechanisms of a pure uu quark pair in the final state from the proton. Although there is no distinct peak structure in the cross sections, a non-negligible excess over the theoretical predictions is observed at E-gamma= 1.5-1.8 GeV. The asymmetries are found to be negative in most of the present kinematical regions, suggesting the dominance of n exchange in the t channel. The negative asymmetries at forward meson production angles are different from the asymmetries previously measured for the photoproduction reactions producing a dd(-) or an ss quark pair in the final state. Advanced theoretical models introducing nucleon resonances and additional unnatural-parity exchanges are needed to reproduce the present data.</P>

A human mitochondrial poly(A) polymerase mutation reveals the complexities of post-transcriptional mitochondrial gene expression

Wilson, William C.,Hornig-Do, Hue-Tran,Bruni, Francesco,Chang, Jeong Ho,Jourdain, Alexis A.,Martinou, Jean-Claude,Falkenberg, Maria,Spå,hr, Henrik,Larsson, Nils-Gö,ran,Lewis, Richard J.,Hewit Oxford University Press 2014 Human Molecular Genetics Vol.23 No.23

<P>The p.N478D missense mutation in human mitochondrial poly(A) polymerase (mtPAP) has previously been implicated in a form of spastic ataxia with optic atrophy. In this study, we have investigated fibroblast cell lines established from family members. The homozygous mutation resulted in the loss of polyadenylation of all mitochondrial transcripts assessed; however, oligoadenylation was retained. Interestingly, this had differential effects on transcript stability that were dependent on the particular species of transcript. These changes were accompanied by a severe loss of oxidative phosphorylation complexes I and IV, and perturbation of <I>de novo</I> mitochondrial protein synthesis. Decreases in transcript polyadenylation and in respiratory chain complexes were effectively rescued by overexpression of wild-type mtPAP. Both mutated and wild-type mtPAP localized to the mitochondrial RNA-processing granules thereby eliminating mislocalization as a cause of defective polyadenylation. <I>In vitro</I> polyadenylation assays revealed severely compromised activity by the mutated protein, which generated only short oligo(A) extensions on RNA substrates, irrespective of RNA secondary structure. The addition of LRPPRC/SLIRP, a mitochondrial RNA-binding complex, enhanced activity of the wild-type mtPAP resulting in increased overall tail length. The LRPPRC/SLIRP effect although present was less marked with mutated mtPAP, independent of RNA secondary structure. We conclude that (i) the polymerase activity of mtPAP can be modulated by the presence of LRPPRC/SLIRP, (ii) N478D mtPAP mutation decreases polymerase activity and (iii) the alteration in poly(A) length is sufficient to cause dysregulation of post-transcriptional expression and the pathogenic lack of respiratory chain complexes.</P>

Inverted-conical light guide for crosstalk reduction in tightly-packed scintillator matrix and MAPMT assembly

Chang, Y.-Y.,Chen, C.R.,Chen, P.,Huang, J.-J.,Huang, M.A.,Liu, T.-C.,Nam, J.W.,Wang, M.-Z.,Bogomolov, V.,Brandt, S.,Budtz-Jørgensen, C.,Castro-Tirado, A.J.,Choi, H.S.,Connell, P.H.,Eyles, C.,Jeong, S. Elsevier 2015 Nuclear Instruments & Methods in Physics Research. Vol.771 No.-

<P><B>Abstract</B></P> <P>In this paper we present the Inverted-Conical light guide designed for optical crosstalk reduction in the scintillator-MAPMT assemblies. The research was motivated by the 30% crosstalk observed in <I>UFFO</I> X-ray telescope, <I>UBAT</I>, during the preliminary calibration with MAPMTs of 64 2.88 × 2.88 mm<SUP>2</SUP> pixels and identically gridded YSO crystal matrices. We began the study with the energy and crosstalk calibrations of the detector, then we constructed a GEANT4 simulation with the customized metallic film model as the MAPMT photocathode. The simulation reproduced more than 70% of the crosstalk and explained it as a consequence of the total reflection produced by the photocathode. The result indicated that the crosstalk mechanism could be a common case in most of the contact-assembled scintillation detectors. The concept of the Inverted-Conical light guide was to suppress the total reflection by contracting the incident angle of the scintillation. We optimized the design in the simulation and fabricated a test sample. The test sample reduced 52% crosstalk with a loss of 6% signal yield. The idea of the Inverted-Conical light guide can be adapted by scintillation detectors multi-pixel, imaging-purpose scintillation detectors such as the ultra-fast GRB observatory <I>UFFO-UBAT</I>, whose performances are sensitive to responding time, image resolution, and geometrical modifications.</P>

Magnetite graphene oxide encapsulated in alginate beads for enhanced adsorption of Cr(VI) and As(V) from aqueous solutions: Role of crosslinking metal cations in pH control

Vu, H.C.,Dwivedi, A.D.,Le, T.T.,Seo, S.H.,Kim, E.J.,Chang, Y.S. Elsevier 2017 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.307 No.-

Graphene oxide has been utilized effectively for the adsorption of heavy metals. Incorporation of graphene oxide with magnetite nanoparticles through co-precipitation enhances separation of a newly designed magnetite graphene oxide by a magnetic field. Considering the instability of magnetite graphene oxide under different water chemistry conditions, we designed encapsulated magnetite graphene oxide inside a non-toxic alginate bead as a high-performance green chemical for the uptake of Cr(VI) and As(V) in water treatment applications (mGO/bead). The alginate, itself revealed low contribution for metal ions uptake, however this could potentially inhibit the aggregation of magnetite graphene oxide powder showing enhanced performance to extract metals from water. Material capacity minimally altered over a range of pH values for As(V), while Cr(VI) uptake varied with pH changes, which were explained by a local pH-controlled mechanism. Induced hydrolysis was facilitated by the release of Fe<SUP>3+</SUP> from Fe<SUP>3+</SUP>-crosslinked mGO/beads, thus enhancing the removal of Cr(VI). For a complex mixture of heavy metals, influence of the presence of co-occurring ions in a mixed contaminant system (Cr(VI), As(V), Cu(II), Cd(II)) revealed an excellent performance (~80-100% removal) by the composite material. The mGO/bead maintained its activity in wastewater and exhibited greater adsorption efficiency for both Cr(VI) and As(V) compared with activated carbon and carbon nanotube. The mGO/beads could be collected and reused for at least 5 cycles without the leaching of core mineral contents. The results indicate the advantages of mGO/beads over the popular adsorbents that can be developed as a versatile material for water treatment.

Design and calibration of a wireless laser-based optical sensor for crack propagation monitoring

S.H. Man,C.C. Chang,M. Hassan,A. Bermak 국제구조공학회 2015 Smart Structures and Systems, An International Jou Vol.15 No.6

In this study, a wireless crack sensor is developed for monitoring cracks propagating in two dimensions. This sensor is developed by incorporating a laser-based optical navigation sensor board (ADNS-9500) into a smart wireless platform (Imote2). To measure crack propagation, the Imote2 sends a signal to the ADNS-9500 to collect a sequence of images reflected from the concrete surface. These acquired images can be processed in the ADNS-9500 directly (the navigation mode) or sent to Imote2 for processing (the frame capture mode). The computed crack displacement can then be transmitted wirelessly to a base station. The design and the construction of this sensor are reported herein followed by some calibration tests on one prototype sensor. Test results show that the sensor can provide sub-millimeter accuracy under sinusoidal and step movement. Also, the two modes of operation offer complementary performance as the navigation mode is more accurate in tracking large amplitude and fast crack movement while the frame capture mode is more accurate for small and slow crack movement. These results illustrate the feasibility of developing such a crack sensor as well as point out directions of further research before its actual implementation.

Molecular cloning, characterization and mRNA expression of duck interleukin-17F

Kim, W.H.,Fernandez, C.P.,Diaz, J.A.R.,Jeong, J.,Kim, S.,Lillehoj, H.S.,Chang, H.H.,Min, W. Elsevier 2015 Veterinary immunology and immunopathology Vol. No.

Interleukin-17F (IL-17F) is a proinflammatory cytokine that plays an important role in gut homeostasis. A full-length duck IL-17F (duIL-17F) cDNA with a 510-bp coding region was identified in ConA-activated splenic lymphocytes. duIL-17F is predicted to encode 166 amino acids, including a 26-amino acid signal peptide, a single N-linked glycosylation site, and six cysteine residues that are conserved in mammalian IL-17. duIL-17F shares 77.5% amino acid sequence identity with chicken IL-17F (chIL-17F), 37-46% with corresponding mammalian homologues, and 53.5% with the previously described duck IL-17A (duIL-17A). The duIL-17F transcripts were expressed in a wide range of untreated tissues; levels were highest in the liver and moderate in the thymus, bursa, kidney, and intestinal tissues. Expression levels of duIL-17F transcript were slightly up-regulated in ConA- and LPS-activated splenic lymphocytes but not in poly I:C stimulated cells. duIL-17F forms heterodimers with duIL-17A. Recombinant duIL-17F, like duIL-17A, induced IL-1β, IL-6, and IL-8 expression in duck embryonic fibroblasts (DEFs). duIL-17A, but not duIL-17F expression, was significantly up-regulated in the liver and spleen of Salmonella Typhimurium-infected ducks. Further analysis of the contributions of IL-17F to different Salmonella spp. or other disease models will be required to expand our understanding of its biological functions.

Synthesis and Linear Viscoelasticity of Polystyrene Stars with a Polyketone Core

Polgar, L. M.,Lentzakis, H.,Collias, D.,Snijkers, F.,Lee, S.,Chang, T.,Sakellariou, G.,Wever, D. A. Z.,Toncelli, C.,Broekhuis, A. A.,Picchioni, F.,Gotsis, A. D.,Vlassopoulos, D. American Chemical Society 2015 Macromolecules Vol.48 No.18

<P>We report on a novel synthetic route to synthesize relatively large quantities of polystyrene (PS) star polymers with targeted arm functionality and molar mass and their rheological properties in the molten state. The synthetic route involves grafting styrene monomers onto a modified (aliphatic, alternating) polyketone backbone with a specific number of initiating grafting sites using controlled atom transfer radical polymerization (ATRP). Several polyketone precursors were used. This resulted in a large array of star polystyrenes with nonspherical cores and varying average arm length and number of arms. Their linear viscoelasticity was investigated and discussed in the context of the known response of anionically synthesized stars. Using a powerful characterization toolbox, including state-of-the-art interaction chromatography, rheometry, and tube modeling via the branch-on-branch (BoB) algorithm, we have assessed the viscoelasticity of these star polymers quantitatively. In particular, we have demonstrated a variability in molecular structure, which differs substantially from their anionically synthesized counterparts. Hence, whereas this new family of star polymers is not recommended for fundamental studies of polymer physics such as the molecular origin of relaxation mechanisms without prior extensive fractionation, they could be used in studies of mixtures as well as industrially relevant processing operations that require large amounts of polymeric stars.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/mamobx/2015/mamobx.2015.48.issue-18/acs.macromol.5b01434/production/images/medium/ma-2015-01434h_0012.gif'></P>

Characterization of Large Structural Genetic Mosaicism in Human Autosomes

Machiela, Mitchell J.,Zhou, W.,Sampson, Joshua N.,Dean, Michael C.,Jacobs, Kevin B.,Black, A.,Brinton, Louise A.,Chang, I.S.,Chen, C.,Chen, C.,Chen, K.,Cook, Linda S.,Crous Bou, M.,De Vivo, I.,Doherty University of Chicago Press [etc.] 2015 American journal of human genetics Vol.96 No.3

Analyses of genome-wide association study (GWAS) data have revealed that detectable genetic mosaicism involving large (>2 Mb) structural autosomal alterations occurs in a fraction of individuals. We present results for a set of 24,849 genotyped individuals (total GWAS set II [TGSII]) in whom 341 large autosomal abnormalities were observed in 168 (0.68%) individuals. Merging data from the new TGSII set with data from two prior reports (the Gene-Environment Association Studies and the total GWAS set I) generated a large dataset of 127,179 individuals; we then conducted a meta-analysis to investigate the patterns of detectable autosomal mosaicism (n = 1,315 events in 925 [0.73%] individuals). Restricting to events >2 Mb in size, we observed an increase in event frequency as event size decreased. The combined results underscore that the rate of detectable mosaicism increases with age (p value = 5.5 x 10<SUP>-31</SUP>) and is higher in men (p value = 0.002) but lower in participants of African ancestry (p value = 0.003). In a subset of 47 individuals from whom serial samples were collected up to 6 years apart, complex changes were noted over time and showed an overall increase in the proportion of mosaic cells as age increased. Our large combined sample allowed for a unique ability to characterize detectable genetic mosaicism involving large structural events and strengthens the emerging evidence of non-random erosion of the genome in the aging population.