Terrestrial n-alkanes and their carbon isotope records from the Hanon paleo-maar sediment, Jeju Island, Korea: Implications for paleoclimate and paleovegetation over the last 35 kyrs

Hyun, S.,Shin, K.H.,Lee, S.C.,Chang, S.W.,Nam, S.I. Pergamon Press 2017 QUATERNARY INTERNATIONAL Vol.441 No.1

<P>The carbon isotope of total carbon (delta C-13(org)), long-chain n-alkanes, and their compound-specific carbon isotope ratios (delta C-13(ALK)) were investigated in the Hanon paleo-maar sediment, Jeju Island of Korea to understand paleoclimate variabilities and their paleovegetation linkages. Based on the organic geochemical data (TOC (%), TN (%), and their delta C-13(org) and delta N-15), the core column stratigraphy was divided into three units, namely from the bottom to 14.5 ka (Unit I), from 14.5 ka to 3.01<a (Unit II), and from 3.0 ka to the core top (Unit III), respectively. In particular, delta C-13(org) showed marked fluctuation from -17.31%o to -28.68%o, suggesting different organic carbon sources. A relatively narrow range of variation in delta C-13(org) was observed in Unit III, and drastic changes in delta C-13(org) were observed from Unit I to Unit II. This may indicate a predominance of C-4 plants in Unit I, and drastic changes from terrestrial C-4 to C-3 in Unit II and predominance of C-3 plants in Unit III. The distributions of n-alkane were characterized by a continuous predominance of odd-numbered n-alkanes, particularly nC(29) and nC(31), and by high fluctuation of the total n-alkanes concentration. The average chain length (ACL), carbon preferences index (CPI), and paleoplant proxy (Paq) showed high fluctuation and glacial-interglacial variations with distinctive a high and low ratio at about 9.2 ka, corresponding to the switching points of delta C-13(org) and a high concentration of nalkane distribution. Individual n-alkane odd-numbered isotopes of delta C-13(Auc) ranged between -11.80%o in delta C-13n(21) and -34.93%o in delta C-13n(31), suggesting different sources of n-alkanes. The distribution of n-alkanes and their individual delta C-13(Auc), in particular delta C-13n(21), support paleovegetation changes, and their time dependent variations matched well with glacial-interglacial paleoclimate variations. Therefore, organic geochemical proxies recorded in Hanon paleo-maar sediment reflects paleoclimate variabilities as well as paleovegetation changes for the last 35 kyr in Jeju Island, Korea. (C) 2016 Elsevier Ltd and INQUA. All rights reserved.</P>

Interaction of Methanol and Hydrogen on a ZnO (0001) Single Crystal Surface

Roy, Probir C.,Doh, Won Hui,Jo, Sam K.,Kim, Chang Min American Chemical Society 2013 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.117 No.29

<P>Thermal reactions of CH<SUB>3</SUB>OH on a ZnO (0001) surface with and without coadsorbed atomic hydrogen have been investigated using a temperature-programmed desorption (TPD) technique. Both H<SUB>2</SUB> and CH<SUB>2</SUB>O desorb at 510 and 580 K during CH<SUB>3</SUB>OH decomposition on ZnO(0001). When H atoms are adsorbed on ZnO(0001), the recombinative desorption of H<SUB>2</SUB> takes place at around 450 K. In the process of CH<SUB>3</SUB>OH decomposition on ZnO(0001), H<SUB>2</SUB> desorption is not observed until the surface temperature reaches 510 K. These observations indicate that surface-bound H atoms are not produced up to 510 K. When CD<SUB>3</SUB>OD and H are coadsorbed, the desorption of both H<SUB>2</SUB> and HD is observed at 445 K. HD should be formed by the exchange reaction between CD<SUB>3</SUB>O–D and H on the surface, which indicates that the CD<SUB>3</SUB>O–D bond is partially broken to form an associative CD<SUB>3</SUB>···D complex. We suggest two different pathways for the formation of CH<SUB>2</SUB>O from CH<SUB>3</SUB>OH on ZnO(0001). At 510 K, CH<SUB>2</SUB>O and H<SUB>2</SUB> are formed from the surface reaction of CH<SUB>3</SUB>O and H. Desorption of CH<SUB>2</SUB>O at 580 K is related to the complete decomposition of CH<SUB>3</SUB>O.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2013/jpccck.2013.117.issue-29/jp403913h/production/images/medium/jp-2013-03913h_0007.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/jp403913h'>ACS Electronic Supporting Info</A></P>

Photoproduction of <tex> $ \Uplambda $</tex> and <tex> $ \Upsigma ^{0}$</tex> hyperons off protons with linearly polarized photons at <tex> $ E_{\gamma }=1.5\hbox{--}3.0$</tex> GeV

Shiu, S. H.,Kohri, H.,Chang, W. C.,Ahn, D. S.,Ahn, J. K.,Chen, J. Y.,Daté,, S.,Ejiri, H.,Fujimura, H.,Fujiwara, M.,Fukui, S.,Gohn, W.,Hicks, K.,Hotta, T.,Hwang, S. H.,Imai, K.,Ishikawa, T.,Joo, American Physical Society 2018 Physical Review C Vol.97 No.1

<P>We report the measurement of the gamma p -> K+Lambda and gamma p -> K+Sigma(0) reactions at SPring-8. The differential cross sections and photon-beam asymmetries are measured at forward K+ production angles using linearly polarized tagged-photon beams in the range of E-gamma = 1.5-3.0 GeV. With increasing photon energy, the cross sections for both gamma p -> K+Lambda and gamma p -> K+Sigma(0) reactions decrease slowly. Distinct narrow structures in the production cross section have not been found at E gamma = 1.5-3.0 GeV. The forward peaking in the angular distributions of cross sections, a characteristic feature of t-channel exchange, is observed for the production of Lambda in the whole observed energy range. A lack of similar feature for Sigma(0) production reflects a less dominant role of t-channel contribution in this channel. The photon-beam asymmetries remain positive for both reactions, suggesting the dominance of K* exchange in the t channel. These asymmetries increase gradually with the photon energy, and have a maximum value of +0.6 for both reactions. Comparison with theoretical predictions based on the Regge trajectory in the t channel and the contributions of nucleon resonances indicates the major role of t-channel contributions as well as non-negligible effects of nucleon resonances in accounting for the reaction mechanism of hyperon photoproduction in this photon energy regime.</P>

Aerosol delivery of eukaryotic translation initiation factor 4E-binding protein 1 effectively suppresses lung tumorigenesis in K-ras^LA1 mice

Chang, S-H,Kim, J-E,Lee, J-H,Minai-Tehrani, A,Han, K,Chae, C,Cho, Y-H,Yun, J-H,Park, K,Kim, Y-S,Cho, M-H Nature America, Inc. 2013 Cancer gene therapy Vol.20 No.6

Conventional radiotherapy or chemotherapy for the long-term survival of patients with lung cancer is still difficult for treatment in metastatic and advanced tumors. Therefore, the safe and effective approaches to the treatment of lung cancer are needed. In this study, the effect of delivered eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) on lung cancer progression was evaluated. Recombinant adeno-associated virus (rAAV)-M3/4E-BP1 was delivered into 6-week-old K-ras<SUP>LA1</SUP> lung cancer model mice through a nose-only inhalation system twice a week for 4 weeks. Long-term repeated delivery of 4E-BP1 effectively reduced tumor progression in the lungs of K-ras<SUP>LA1</SUP> mice. Reduction of eIF4E by overexpression of 4E-BP1 resulted in suppression of cap-dependent protein expression of basic fibroblast growth factor (bFGF or FGF-2) and vascular endothelial growth factor (VEGF). In addition, delivered 4E-BP1 inhibited the proliferation of lung cancer cells in K-ras<SUP>LA1</SUP> mice model. Our results suggest that long-term repeated viral delivery of 4E-BP1 may provide a useful tool for designing lung cancer treatment.

MATRA-LMR-FB assessment with THORS bundle 2B experiments

Chang, W.P.,Jin, Y.,Choi, C.W.,Ha, K.S. Elsevier 2015 Nuclear engineering and design Vol.282 No.-

<P><B>Abstract</B></P> <P>In this study, the ‘THORS (Thermal-Hydraulic Out-of-Reactor Safety) bundle 2B’ test data in ORNL (Oak Ridge National Laboratory, US) were used to supplement a qualification of the MATRA-LMR-FB code. The code was developed to analyze a sub-channel blockage accident in a Sodium cooled Fast Reactor (SFR), as an effort to enhance its reliability for an analysis of a blockage disturbance. The ‘THORS bundle 2B’ test was conducted to investigate the thermal-hydraulic effects of 24% and 45% sub-channel inlet blockages with a 19-pin bundle. The test covered several flow rates at the bundle inlet with different bundle powers. The MATRA-LMR-FB predictions were compared with not only the CFX simulation results but also the test data.</P> <P>As a result, most of the comparative results between the MATRA-LMR-FB predictions and the test data lay within a range of ±15°C. Such differences were not usually derailed much from other predictions found in a literature survey. The code, however, is slightly biased toward an under-prediction, with the most probable difference occurring at around −2 to −4°C. Nevertheless, it was anticipated that the comparison will supplement the applicability of the MATRA-LMR-FB to a partial flow blockage accident in a subassembly of an SFR. The CFX simulation results mostly agreed with the MATRA-LMR-FB predictions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MATRA-LMR-FB code has been developed to analyze a flow blockage in an SFR. </LI> <LI> Qualifying a MATRA-LMR-FB prediction capability using THORS bundle 2B test data. </LI> <LI> CFX simulation of the test for comparison analysis. </LI> <LI> MATRA-LMR-FB predicted most of the test data within a range of ±15°C. </LI> </UL> </P>

Preparation, Ferroelectric and Electrical Properties of Lead Germanate Pb5Ge3O11 thin films prepared by sol-gel methods

C.H. Chang,J.S. Kim,H.S. Lee,J.K. Kim,S.S. Kim,T.K. Song 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.46 No.1

Lead germanate Pb5Ge3O11 (PGO) thin flms were prepared by sol-gel methods and their electrical properties were obtained. Single phase of prepared PGO thin flm was confrmed by X-ray diraction peaks. PGO thin lms with c-axis oriented grains were prepared on (111) Pt-coated Si substrates when heat treated at 450C 600C for 1 h. Grains showed a plate like shape and grain size was increased with increasing annealing temperature. PGO thin lms were found to be ferroelectric at room temperature, and remanent polarization was about 4 C/cm2 at a coercive feld of 100 kV/cm. In this work, preparation, ferroelectric and electrical properties of PGO thin flms were investigated.

Magnetic resonance tracking of multifunctional nanoparticle-labeled mouse mesenchymal stem cells in a mouse model of myocardial infarction

Lee, K.,Park, C.,Moon, H.Y.,Ahn, E.,Park, H.E.,Ihm, S.H.,Seung, K.B.,Yoon, T.J.,Chang, K.,Lee, C.,Cheong, C.,Hong, K.S. Elsevier 2009 Current Applied Physics Vol.9 No.1

Magnetic ferrite nanoparticles (MNPs) are nano-sized magnets that distort the local magnetic field and alter the T<SUB>2</SUB> and T<SUB>2</SUB><SUP>*</SUP> of the water protons in the surrounding water molecules. This property renders MNPs a favorable negative MR contrast agent for biomedical applications. Silica coating and polyethylene glycolation confers additional stability and biocompatibility to the MNPs. Organic dyes incorporated into the silica shell enable the detection of MNP fluorescence by confocal laser scanning microscopy (CLSM). Mouse mesenchymal stem cells (mMSCs) in adult bone marrow can differentiate into cardiomyocytes. The mMSCs recruited in the region of myocardial infarction can express muscle-specific markers and increase the regional wall motion. Using MRI, we tracked the fate of MNP-labeled mMSCs injected into the infarcted myocardium. The mMSCs were effectively labeled with polyethylene-glycolated MNPs, as confirmed by CLSM. The MNP-labeled mMSCs were injected around and into the infarcted myocardium of C57/BL6 mice. Using MR, we successfully tracked the MNP-labeled mMSCs in the hearts of mice at 7d after inducing myocardial infarction. The localization of MNPs in the myocardium was validated by the in vivo and ex vivo MR images.

드로잉 금형에 있어서 비드의 영향

고관영,최원정,조재희,명노훈,이창수,최병용,허주환,최창권,장종훈,장윤철,박기용 울산과학대학 2001 연구논문집 Vol.28 No.1

본 연구는 자체 제작한 다이 측 비드가 설치 된 드로잉 금형을 이용하여 SUS 304, 6:4 황동 판재를 드로잉 가공하여 생산된 제품의 치수변형 특성을, 비드를 설치하지 않은 자유 드로잉 하여 얻은 제품과 비교하였다. SUS 304 판재의 경우, 비드를 설치하여 드로잉 한 경우는 늘어난 길이의 변화가 연속적으로 증가하고 있고, 비드를 설치하지 않은 경우는 마지막 부분에서 다시 회복상태를 보였다. 그 원인은 드로잉 비드로 인하여 적정량의 유입으로 일정 비율로 늘어난 것이라고 볼 수 있다. 6:4 황동 판재의 경우는 비드를 설치한 경우의 치수 변형값이 비드를 설치하지 않은 경우보다 안정함을 보여주었다. In this research, properties of SUS 304 and 6:4 brass products produced by die bead-drawing mold were compared with those of products drawed without bead. In the case of bead-SUS-plate, variation of incremental length progressively increases, while, in the case of no bead-SUS-plate, recovery appeared at the final-part. The reason of this difference is considered as proper insert of metal-plate on the basis of bead. Bead-6:4 brass-plate showed more stable data than no-bead die case although it did not show recovery in final-part.

Selective production of 1-monocaprin by porcine liver carboxylesterase-catalyzed esterification: Its enzyme kinetics and catalytic performance

Park, K.M.,Lee, J.H.,Hong, S.C.,Kwon, C.W.,Jo, M.,Choi, S.J.,Kim, K.,Chang, P.S. IPC Science and Technology Press ; Elsevier Scienc 2016 Enzyme and microbial technology Vol.82 No.-

<P>Porcine liver carboxylesterase (PLE) belongs to carboxylesterase family (EC 3.1.1.1) as a serine-type esterase. The PLE-catalyzed esterification of capric acid with glycerol in reverse micelles was investigated on the catalytic performance and enzyme kinetics. The most suitable structure of reverse micelles was comprised of isooctane (reaction medium) and bis(2-ethylhexyl) sodium sulfosuccinate (AOT, anionic surfactant) with 0.1 of R-value ([water]/[surfactant]) and 3.0 of G/F-value ([glycerol]/[fatty acid]) for the PLE-catalyzed esterification. In the aspect of regio-selectivity, the PLE mainly produced 1-monocaprin without any other products (di- and/or tricaprins of subsequent reactions). Furthermore, the degree of esterification at equilibrium state (after 4 h from the initiation) was 62.7% under the optimum conditions at pH 7.0 and 60 degrees C. Based on Hanes-Woolf plot, the apparent K-m and V-max values were calculated to be 16.44 mM and 38.91 mu M/min/mg protein, respectively. (C) 2015 Elsevier Inc. All rights reserved.</P>

옥수수 - 대두박 사료내 미생물 Phytase 의 첨가가 브로일러의 생산능력에 미치는 영향

손광수,권관,권찬호,장재익,주종철,유문일,최양웅 한국축산학회 1999 한국축산학회지 Vol.41 No.5

This experiment was conducted to evaluate the effects of a domestic phytase originated from bacterial source on performance of starter and Bower broiler chicks. It was basically designed to meet NRC requirement for the contents of calcium and phosphorus when the contents of Ca and P in the feeds were met to 100%(Control; C) and 80%(P0) of the NRC requirement. Three different bacterial phytase(0, 300, 500PU) were supplemented to basal diet and compared it's effect on growth performance, nutritional digestibility, fecal N and P excretion, tibial Ca and P content. A total 200 broiler chicks were assigned to 4 treatments with 5 replications per treatment, 10 chicks of each replication. The weight gain(1,581.6g) in control treatment(C) was slightly higher than that of P0(1,557.7g). Although phytase treatments(P300 and P500) tended to show higher weight gain as compared to treatments without phytase, there were no significant differences among the treatments. No differences were observed among dietary treatments for feed efficiency although broiler chicks fed control diet (1.94) tended to show slightly better feed efficiency than those fed P0 diet(1.99). The excretion of P per kg weight gain tended to be decreased by 17% when 300PU of bacterial phytase was fed to starter and by 10% when 500PU was fed to Bower. However, there were no statistical significances among the treatments. It was concluded that the addition of phytase had neither affects in improving of utilization efficiencies of dry matter, crude protein, and crude fat, nor efficiencies of Ca and P. The supplemental of phytase at the level of 500 ppm for both stages of broiler chick diets was assumed to appropriate.