Facile synthesis of monodispersed 3D hierarchical Fe₃O₄ nanostructures decorated r-GO as the negative electrodes for Li-ion batteries

Kumar, S. Rajesh,Kim, Jong Guk,Viswanathan, C.,Kim, Won Bae,Selvan, R. Kalai,Ponpandian, N. Elsevier 2018 Materials research bulletin Vol.97 No.-

<P><B>Abstract</B></P> <P>One-pot solvothermal process is adopted to develop, 3D hierarchical Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles supported 2D reduced graphene oxide sheets (Fe<SUB>3</SUB>O<SUB>4</SUB>/r-GO) as possible negative electrodes for lithium ion batteries. The synthesis parameters are optimized to prepare agglomeration-free Fe<SUB>3</SUB>O<SUB>4</SUB> nanostructures with uniform size and shape on r-GO. The field emission scanning electron microscopic (FESEM) image reveals that the 3D hierarchical Fe<SUB>3</SUB>O<SUB>4</SUB> nanostructures are uniformly decorated on r-GO. The physicochemical and functional properties of Fe<SUB>3</SUB>O<SUB>4</SUB>/r-GO are systematically investigated using various techniques. The fabricated Fe<SUB>3</SUB>O<SUB>4</SUB>/r-GO electrode delivers an initial discharge capacity of 1221mAhg<SUP>−1</SUP> at a current density of 100mAg<SUP>−1</SUP> and retains the specific capacity of 1560mAhg<SUP>−1</SUP> after 100 cycles. Fe<SUB>3</SUB>O<SUB>4</SUB>/r-GO significantly enhances cyclic performance, when compared with bare Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles due to the uniform distribution of Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles on the graphene sheet with the more number of electrochemically active sites.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Monodispersed Fe<SUB>3</SUB>O<SUB>4</SUB> nanostructures with different shapes synthesized by solvothermal method. </LI> <LI> The fabricated Fe<SUB>3</SUB>O<SUB>4</SUB>/r-GO electrode delivers an initial discharge capacity of 1221mAhg<SUP>−1</SUP> at 100mAhg<SUP>−1</SUP>. </LI> <LI> Fe<SUB>3</SUB>O<SUB>4</SUB>/r-GO significantly enhances the cyclic stability and rate capability than bare Fe<SUB>3</SUB>O<SUB>4</SUB> nanoparticles </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Mandelic Acid 정량을 위한 은 나노입자에 의해 증가된 화학발광분석법

( Md R-mahmnur Alam ),( Mohammad Kamruzzaman ),김소연 ( So Yeon Kim ),조해진 ( Hae Jin Jo ),이상학 ( Sang Hak Lee ),김영호 ( Young Ho Kim ),최종하 ( Jong Ha Choi ) 한국공업화학회 2011 응용화학 Vol.15 No.1

A sensitive silver nanoparticles (Ag NPs) enhanced chemiluminescence (CL) method is reported for the determination of mandelic acid (MA). This method is based on the luminol-KIO4 system catalyzed by Ag NPs to produce CL spectra. Prepared Ag NPs were characterized by UV-visible spectra and TEM image. Under optimal condition, CL spectra of the system were responded linearly with the concentration of MA in the range of 2.5×10(-9) to 2.0×10(-8) mol L(-1)(r=0.9989) with a detection limit of 1.2×10(-10) mol L(-1). The relative standard deviation of 1.0×10(-7) mol L(-1) MA was found 1.45 (n=9).

Transient receptor potential vanilloid type-1 channel regulates diet-induced obesity, insulin resistance, and leptin resistance

Lee, Eunjung,Jung, Dae Young,Kim, Jong Hun,Patel, Payal R.,Hu, Xiaodi,Lee, Yongjin,Azuma, Yoshihiro,Wang, Hsun-Fan,Tsitsilianos, Nicholas,Shafiq, Umber,Kwon, Jung Yeon,Lee, Hyong Joo,Lee, Ki Won,Kim, The Federation of American Societies for Experimen 2015 The FASEB Journal Vol.29 No.8

<P>Insulin resistance is a major characteristic of obesity and type 2 diabetes, but the underlying mechanism is unclear. Recent studies have shown a metabolic role of capsaicin that may be mediated <I>via</I> the transient receptor potential vanilloid type-1 (TRPV1) channel. In this study, TRPV1 knockout (KO) and wild-type (WT) mice (as controls) were fed a high-fat diet (HFD), and metabolic studies were performed to measure insulin and leptin action. The TRPV1 KO mice became more obese than the WT mice after HFD, partly attributed to altered energy balance and leptin resistance in the KO mice. The hyperinsulinemic-euglycemic clamp experiment showed that the TRPV1 KO mice were more insulin resistant after HFD because of the ∼40% reduction in glucose metabolism in the white and brown adipose tissue, compared with that in the WT mice. Leptin treatment failed to suppress food intake, and leptin-mediated hypothalamic signal transducer and activator of transcription (STAT)-3 activity was blunted in the TRPV1 KO mice. We also found that the TRPV1 KO mice were more obese and insulin resistant than the WT mice at 9 mo of age. Taken together, these results indicate that lacking TRPV1 exacerbates the obesity and insulin resistance associated with an HFD and aging, and our findings further suggest that TRPV1 has a major role in regulating glucose metabolism and hypothalamic leptin’s effects in obesity.—Lee, E., Jung, D. Y., Kim, J. H., Patel, P. R., Hu, X., Lee, Y., Azuma, Y., Wang, H.-F., Tsitsilianos, N., Shafiq, U., Kwon, J. Y., Lee, H. J., Lee, K. W., Kim, J. K. Transient receptor potential vanilloid type-1 channel regulates diet-induced obesity, insulin resistance, and leptin resistance.</P>

Testing for the Long-Run Reationship between Inflation and its Variability

Park, Young Bae,Slater, Jin R.,Kim, Jong Soo 한국생산성학회 1997 THE JOURNAL OF PRODUCTIVITY Vol.3 No.1

In this paper the long-run relationship between relative price and inflation has been examined for the U.K historical price data set. Generally, the traditional inference procedures are inappropriate since relative price and inflation series are non-stationary. Two significant findings are reported in the paper. First, it is demonstrated, using a multivariate cointegration technique, that a long-run relationship between relative price and inflation is an exist. Second, we apply the Phillips-Hansen fully modified estimation to test this relationship and found that the relationships can be rejected for all the sample periods examined.

The kinematic evolution of the Macquarie Plate: A case study for the fragmentation of oceanic lithosphere

Choi, Hakkyum,Kim, Seung-Sep,Dyment, Jé,rô,me,Granot, Roi,Park, Sung-Hyun,Hong, Jong Kuk Elsevier 2017 Earth and planetary science letters Vol.478 No.-

<P><B>Abstract</B></P> <P>The tectonic evolution of the Southeast Indian Ridge (SEIR), and in particular of its easternmost edge, has not been constrained by high-resolution shipboard data and therefore the kinematic details of its behavior are uncertain. Using new shipboard magnetic data obtained by R/VIB <I>Araon</I> and M/V <I>L'Astrolabe</I> along the easternmost SEIR and available archived magnetic data, we estimated the finite rotation parameters of the Macquarie–Antarctic and Australian–Antarctic motions for eight anomalies (1o, 2, 2Ay, 2Ao, 3y, 3o, 3Ay, and 3Ao). These new finite rotations indicate that the Macquarie Plate since its creation ∼6.24 million years ago behaved as an independent and rigid plate, confirming previous estimates. The change in the Australian–Antarctic spreading direction from N–S to NW–SE appears to coincide with the formation of the Macquarie Plate at ∼6.24 Ma. Analysis of the estimated plate motions indicates that the initiation and growth stages of the Macquarie Plate resemble the kinematic evolution of other microplates and continental breakup, whereby a rapid acceleration in angular velocity took place after its initial formation, followed by a slow decay, suggesting that a decrease in the resistive strength force might have played a significant role in the kinematic evolution of the microplate. The motions of the Macquarie Plate during its growth stages may have been further enhanced by the increased subducting rates along the Hjort Trench, while the Macquarie Plate has exhibited constant growth by seafloor spreading.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New finite rotations of Australian–Macquarie–Antarctic Plates over the last ∼7 Myr. </LI> <LI> Macquarie Plate initiation/growth stages resemble kinematic evolution of microplates and continental breakup. </LI> <LI> Oceanic lithosphere fragmentation might serve to accommodate plate reorganization. </LI> </UL> </P>

Streptomyces albus로부터 분리된 Type Ⅱ Polyketide Synthase 유전자의 염기 서열 및 분석

권형진,Huchinson C.R.,진형종,김수언,이계준,서주원 한국산업미생물학회 1995 한국미생물·생명공학회지 Vol.23 No.2

Polyketide 계 이온 투과성 항생제인 salinomycin의 생성 균주인 Streptomyces albus에서 그 생합성 유전자를 분리하기 위하여, actI을 probe로 이용하여 S. albus ATCC 21838 유전자 library로부터 약 24 kb의 S. albus DNA를 포함하고 있는 pWHM 210을 분리하였다. 이 24 kb DNA 중에서 actI에 유사성을 보이는 3.8 kb BamHI 절편을 분리하여 염기 서열을 결정, 분석하였다. 이 영역에 존재하는 두개의 완전한 ORFs가 type II PKS(polyketide synthase)의 β-ketoacyl synthase/acyl transferase와 chain length determining factor 유전자에 해당하는 것임을 확인할 수 있었다. 이들은 잘 보존된 minimal type II PKS 유전자의 일부로, 알려진 다른 type II PKS 유전자들과 높은 유사성을 보였다. Streptomyces albus wild type ATCC 21838 produced salinomycin, polyether antibiotic. To clone genes related salinomycin production, a genomic library was screened using act1 as a DNA hybridization probe. PWHM 210 was isolated, which contained an approximately 24 kb of insert DNA. A 3.8 kb region in the 24 kb insert DNA was hybridized to act1 and the nucleotide sequence of this region was determinied. Two open reading frames found in the same direction were homologous to genes for β-keto acyl synthase/acyl transferase and chain length determining factor in type II PKS (polyketide synthase). The genes were components of minimal type II PKS genes, highly conserved and showed the strong simlarity to other type II PKS genes known today.

SMAD4 Suppresses AURKA-Induced Metastatic Phenotypes via Degradation of AURKA in a TGFβ-Independent Manner

Jia, Lina,Lee, Hun Seok,Wu, Chun Fu,Kundu, Juthika,Park, Sang Gyu,Kim, Ryong Nam,Wang, Li-Hui,Erkin, Ö,zgü,r Cem,Choi, Jong-Sun,Chae, Seoung Wan,Yang, Ho Bin,Choi, Yoon-La,Shin, Young Kee American Association for Cancer Research 2014 Molecular Cancer Research Vol.12 No.12

<P>SMAD4 has been suggested to inhibit the activity of the WNT/β-catenin signaling pathway in cancer. However, the mechanism by which SMAD4 antagonizes WNT/β-catenin signaling in cancer remains largely unknown. Aurora A kinase (AURKA), which is frequently overexpressed in cancer, increases the transcriptional activity of β-catenin/T-cell factor (TCF) complex by stabilizing β-catenin through the inhibition of GSK-3β. Here, SMAD4 modulated AURKA in a TGFβ-independent manner. Overexpression of SMAD4 significantly suppressed AURKA function, including colony formation, migration, and invasion of cell lines. In addition, SMAD4 bound to AURKA induced degradation of AURKA by the proteasome. A luciferase activity assay revealed that the transcriptional activity of the β-catenin/TCF complex was elevated by AURKA, but decreased by SMAD4 overexpression. Moreover, target gene analysis showed that SMAD4 abrogated the AURKA-mediated increase of β-catenin target genes. However, this inhibitory effect of SMAD4 was abolished by overexpression of AURKA or silencing of AURKA in SMAD4-overexpressed cells. Meanwhile, the SMAD4-mediated repression of AURKA and β-catenin was independent of TGFβ signaling because blockage of TGFβR1 or restoration of TGFβ signaling did not prevent suppression of AURKA and β-catenin signaling by SMAD4. These results indicate that the tumor-suppressive function of SMAD4 is mediated by downregulation of β-catenin transcriptional activity via AURKA degradation in a TGFβ-independent manner.</P><P><B>Implications:</B> SMAD4 interacts with AURKA and antagonizes its tumor-promoting potential, thus demonstrating a novel mechanism of tumor suppression. <I>Mol Cancer Res; 12(12); 1779–95. ©2014 AACR</I>.</P>

A study of microRNAs <i>in silico</i> and <i>in vivo</i>: emerging regulators of embryonic stem cells

Kim, Kye-Seong,Kim, Jong S.,Lee, Man R.,Jeong, Hoe S.,Kim, Jaesang Blackwell Publishing Ltd 2009 The FEBS journal Vol.276 No.8

<P>MicroRNAs (miRNAs) are noncoding regulatory RNAs that function via the degradation of target mRNAs and inhibition of translation. They are found widely in higher eukaryotic organisms, and in several species that have been closely examined, hundreds of miRNAs have thus far been discovered with mechanistically conserved, yet functionally diverse, roles necessary for the proper development, homeostasis and metabolism of the organisms. Mammalian cells produce miRNAs in a cell-type-specific manner and utilize them to regulate unique subsets of genes expressed in the host cells. This rule also appears to apply to the pluripotent embryonic stem cells, according to several recent studies that reported identification of specifically expressed miRNAs. Intense interest in these miRNAs stems in part from the possibility that they are one of the determinants of the salient characteristics of these cells: self-renewal capacity and pluripotency. As functional data supporting this hypothesis are beginning to accumulate, it can be envisioned that miRNAs may be useful as molecular tools for manipulating ESCs. This review focuses on the recent discovery and functional characterization of miRNAs in human and mouse ESCs and provides perspectives on future research directions.</P>

Polyphosphoinositides Are Derived from Ether-linked InositolGlycerophospholipids in Rat Brain

Jong S. Kim,Jin K. Lim,Young K. Yeo,Sun H. Shin,Hak R. Kim,Byung K. Choi 한국생화학분자생물학회 2005 BMB Reports Vol.38 No.3

Morphology-performance relationships in polymer/fullerene blends probed by complementary characterisation techniques - effects of nanowire formation and subsequent thermal annealing

Kim, Jong Soo,Wood, Sebastian,Shoaee, Safa,Spencer, Steve J.,Castro, Fernando A.,Tsoi, Wing Chung,Murphy, Craig E.,Sim, Myungsun,Cho, Kilwon,Durrant, James R.,Kim, Ji-Seon The Royal Society of Chemistry 2015 Journal of Materials Chemistry C Vol.3 No.35

<P>We report detailed analysis of the thin film morphology (molecular packing, molecular conformational order, and vertical phase separation) - performance (charge transport, photocurrent generation, and photovoltaic performance) relationships under nanowire formation and subsequent thermal annealing in polymer:fullerene blends. Nanowires of poly(3-hexylthiophene) (P3HT) are formed by controlled precipitation from solution and blended with [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) to form bulk heterojunction thin films. The formation of nanowires and further thermal annealing result in increased molecular order of the P3HT, where the short-range conformational order is maximised by annealing at 100 °C and decreases when annealed at higher temperatures, but the quality of long-range molecular packing and lamellar packing distance increase with annealing temperature up to 150 °C. The long-range order correlates strongly with an increase in hole mobility, but the reduction in short-range conformational order indicates a slight reduction in planarity of the conjugated backbone in this aggregated polymer morphology. Photoconductive atomic force microscopy reveals enhanced connectivity of the hole transporting nanowire network as a result of thermal annealing. Additionally, we find that the nanowire morphology results in a favourable vertical phase separation, with PCBM enrichment at the electron-extracting surface in the conventional architecture, which is contrary to the non-nanowire case. This effect is further encouraged by thermal annealing, resulting in an enhancement of open-circuit voltage, and represents a morphological advantage over conventional P3HT:PCBM devices. Our study identifies an important interplay between long-range and short-range molecular order in charge generation, transport, extraction, and hence solar cell device performance.</P>