Stoichiometric Layered Potassium Transition Metal Oxide for Rechargeable Potassium Batteries

Kim, Haegyeom,Seo, Dong-Hwa,Urban, Alexander,Lee, Jinhyuk,Kwon, Deok-Hwang,Bo, Shou-Hang,Shi, Tan,Papp, Joseph K.,McCloskey, Bryan D.,Ceder, Gerbrand American Chemical Society 2018 Chemistry of materials Vol.30 No.18

<P>K-ion batteries are promising alternative energy storage systems for large-scale applications because of the globally abundant K reserves. K-ion batteries benefit from the lower standard redox potential of K/K<SUP>+</SUP> than that of Na/Na<SUP>+</SUP> and even Li/Li<SUP>+</SUP>, which can translate into a higher working voltage. Stable KC<SUB>8</SUB> can also be formed via K intercalation into a graphite anode, which contrasts with the thermodynamically unfavorable Na intercalation into graphite, making graphite a readily available anode for K-ion battery technology. However, to construct practical rocking-chair K-ion batteries, an appropriate cathode material that can accommodate reversible K release and storage is still needed. We show that stoichiometric KCrO<SUB>2</SUB> with a layered O3-type structure can function as a cathode for K-ion batteries and demonstrate a practical rocking-chair K-ion battery. In situ X-ray diffraction and electrochemical titration demonstrate that K<SUB><I>x</I></SUB>CrO<SUB>2</SUB> is stable for a wide K content, allowing for topotactic K extraction and reinsertion. We further explain why stoichiometric KCrO<SUB>2</SUB> is unique in forming the layered structure unlike other stoichiometric K-transition metal oxide compounds, which form nonlayered structures; this fundamental understanding provides insight for the future design of other layered cathodes for K-ion batteries.</P> [FIG OMISSION]</BR>

Integrin αvβ3-mediated transcriptional regulation of TIMP-1 in a human ovarian cancer cell line

Kim, D.S.,Jeon, O.H.,Lee, H.D.,Yoo, K.H.,Kim, D.S. Academic Press 2008 Biochemical and biophysical research communication Vol.377 No.2

We have previously reported that a disintegrin inhibits solid tumor growth and metastasis in mouse model [I.C. Kang, Y.D. Lee, D.S. Kim, A novel disintegrin salmosin inhibits tumor angiogenesis, Cancer Res. 59 (1999) 3754-3760; S.I. Kim, K.S. Kim, H.S. Kim, D.S. Kim, Y. Jang, K.H. Chung, Y.S. Park, Inhibitory effect of the salmosin gene transferred by cationic liposomes on the progression of B16BL6 tumors, Cancer Res. 63 (2003) 6458-462]. In this study, we have investigated the modulatory effect of a disintegrin, saxatilin, on the balance between MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) in human ovarian cancer cell line MDAH 2774. Functional mechanism of the disintegrin-mediated transcriptional regulation of MMP-9 and TIMP-1 was examined in the ovarian cancer cell line. Saxatilin strongly induced TIMP-1 expression in dose- and time-dependent manners, while the disintegrin suppressed MMP-9 expression. Further analyses clearly indicated that interaction of the disintegrin and integrin αvβ3 results in the TIMP-1 promoter activation via c-fos to suppress TNF-α-induced cancer cell invasion. These results demonstrate that integrin αvβ3-mediated transcriptional regulation of MMP-9 and TIMP-1 is critical for suppressing the ovarian cancer cell invasion.

生體內 藥劑耐性 및 Plasmid 傳達에 關한 硏究

金鎬薰,李明遠,李英姬,金基湘,兪天權,吳明燉,李悌煥,李点揆,琴東吉,鄭泰華,李潤台 국립보건연구원 1989 국립보건원보 Vol.26 No.

Proposed mechanism in the change of cellular composition in the outer medullary collecting duct during potassium homeostasis.

Park, E-Y,Kim, W-Y,Kim, Y-M,Lee, J-H,Han, K-H,Weiner, I D,Kim, J Gutenberg 2012 HISTOLOGY AND HISTOPATHOLOGY Vol.27 No.12

<P>Potassium depletion (K?-D) induces hypertrophy and hyperplasia of collecting duct cells, and potassium repletion (K?-R) induces regression of these changes. The purpose of this study was to examine the time courses of the changes in cellular composition, the origin of intercalated cells (ICs) and the mechanism responsible for these changes. SD rats received K?-depleted diets for 1, 7, or 14 days. After K?-D for 14 days some of the rats received normal diets for 1, 3, 5, or 7 days. In the inner stripe of the outer medulla, K?-D increased significantly the number and proportion of H?-ATPase-positive ICs, but decreased the proportion of H?-ATPase-negative principal cells (PCs). However, proliferation was limited to H?-ATPase-negative PCs. During K?-R, the cellular composition was recovered to control level. Apoptosis increased during K?-R and exclusively limited in H?-ATPase-negative PCs. Double immunolabeling with antibodies to PC and IC markers identified both cells negative or positive for all markers during both K?-D and K?-R. Electron microscopic observation showed that ultrastructure of AE1-positive some cells were similar to AE1-negative some cells during K?-R. LC3 protein expression increased significantly and autophagic vacuoles appeared particularly in PCs on days 14 of K?-D and in ICs on days 3 of K?-R. These results suggest that PCs and ICs may interconvert in response to changes in dietary K+ availability and that autophagic pathways may be involved in the interconversion.</P>

Relationship between Stress Gene Polymorphisms and Litter Size by AI in Pigs

Jin, H.J.,Kim, I.C.,Wee, M.S.,Yeon, S.H.,Kim, C.D.,Lee, S.S.,Cho, C.Y.,Cho, S.R.,Son, D.S.,Park, C.K. 韓國受精卵移植學會 2007 한국동물생명공학회지 Vol.22 No.4

This study was performed to investigate the relationship between PSS-HSP70 gene polymorphism and artificial insemination (AI) reproductivity in the pigs. The RFLP polymorphism of PSS and the SSCP polymorphisms of HSP70 K1, K3 and K4 PCR product were detected different patterns. In the experiment for AI of fresh semen, spring and fall season showed higher litter size born of 10.89 head than 10.47 head of summer season. Landrace was showed higher litter size of 9.96 head than that of Duroc and Yorkshire (p<0.05). Stress relating PSS and HSP70 polymorphism of PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showd a highest litter size born of 10.97 head and litter size born alive of 10.69 head than that of the other polymorphisms(p<0.05). In the experiment for AI of frozen semen, effects of season and pig breeds were not showed for litter size born. The stress relating polymorphism of PSS-Carrier, HSP70 K1-BB, K3-BB, K4-AB showed highest litter size born of 11.29 head and litter size born alive of 10.82 head and PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showed the lowest litter size born of 8.48 head and litter size born alive of 7.33 head than that of the other polymorphisms(p<0.05). These results suggest that AI litter size born for the stress of forzen thawed semen may be affected by PSS and HSP70 polymorphism in pigs.

Protein Profile in Corpus Luteum during Pregnancy in Korean Native Cows

Chung, H.J.,Kim, K.W.,Han, D.W.,Lee, H.C.,Yang, B.C.,Chung, H.K.,Shim, M.R.,Choi, M.S.,Jo, E.B.,Jo, Y.M.,Oh, M.Y.,Jo, S.J.,Hong, S.K.,Park, J.K.,Chang, W.K. Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.11

Steroidogenesis requires coordination of the anabolic and catabolic pathways of lipid metabolism, but the profile of proteins associated with progesterone synthesis in cyclic and pregnant corpus luteum (CL) is not well-known in cattle. In Experiment 1, plasma progesterone level was monitored in cyclic cows (n = 5) and pregnant cows (n = 6; until d-90). A significant decline in the plasma progesterone level occurred at d-19 of cyclic cows. Progesterone level in abbatoir-derived luteal tissues was also determined at d 1 to 5, 6 to 13 and 14 to 20 of cyclic cows, and d-60 and -90 of pregnant cows (n = 5 each). Progesterone level in d-60 CL was not different from those in d 6 to 13 CL and d-90 CL, although the difference between d 6 to 13 and d-90 was significant. In Experiment 2, protein expression pattern in CL at d-90 (n = 4) was compared with that in CL of cyclic cows at d 6 to 13 (n = 5). Significant changes in the level of protein expression were detected in 32 protein spots by two-dimensional polyacrylamide gel electrophoresis (2-DE), and 23 of them were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Six proteins were found only in pregnant CL, while the other 17 proteins were found only in cyclic CL. Among the above 6 proteins, vimentin which is involved in the regulation of post-implantation development was included. Thus, the protein expression pattern in CL was disorientated from cyclic luteal phase to mid pregnancy, and alterations in specific CL protein expression may contribute to the maintenance of pregnancy in Korean native cows.

Relationship between Stress Gene Polymorphisms and Litter Size by AI in Pigs

H. J. Jin,I. C. Kim,M. S. Wee,S. H. Yeon,C. D. Kim,S. S. Lee,C. Y. Cho,S. R. Cho,D. S. Son,C. K. Park,Z. D. Li 사단법인 한국동물생명공학회 2007 한국동물생명공학회지 Vol.22 No.4

This study was performed to investigate the relationship between PSS-HSP70 gene polymorphism and artificial insemination (AI) reproductivity in the pigs. The RFLP polymorphism of PSS and the SSCP polymorphisms of HSP70 K1, K3 and K4 PCR product were detected different patterns. In the experiment for AI of fresh semen, spring and fall season showed higher litter size born of 10.89 head than 10.47 head of summer season. Landrace was showed higher litter size of 9.96 head than that of Duroc and Yorkshire(p<0.05). Stress relating PSS and HSP70 polymorphism of PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showd a highest litter size born of 10.97 head and litter size born alive of 10.69 head than that of the other polymorphisms(p<0.05). In the experiment for AI of frozen semen, effects of season and pig breeds were not showed for litter size born. The stress relating polymorphism of PSS-Carrier, HSP70 K1-BB, K3-BB, K4-AB showed highest litter size born of 11.29 head and litter size born alive of 10.82 head and PSS-Normal, HSP70 K1-BB, K3-AB, K4-AA showed the lowest litter size born of 8.48 head and litter size born alive of 7.33 head than that of the other polymorphisms(p<0.05). These results suggest that AI litter size born for the stress of forzen thawed semen may be affected by PSS and HSP70 polymorphism in pigs.

Optical subthreshold current method for extracting the interface states in MOS systems

Kim, M.S.,Nam, I.C.,Kim, H.T.,Shin, H.T.,Kim, T.E.,Park, H.S.,Kim, K.S.,Kim, K.H.,Choi, J.B.,Min, K.S.,Kim, D.J.,Kang, D.W.,Kim, D.M. IEEE 2004 IEEE electron device letters Vol.25 No.2

Optical subthreshold current method (OSCM) is proposed for characterizing the interface states in MOS systems using the current-voltage characteristics under a photonic excitation. An optical source with a subbandgap (E<SUB>ph</SUB>>E<SUB>g</SUB>) photonic energy (E<SUB>ph</SUB>=0.943 eV, P<SUB>opt</SUB>=+5 dBm), which is less than the silicon bandgap (E<SUB>g</SUB>=1.12;eV), is employed for the optical subthreshold current characterization of interface states in the photoresponsive energy band. We applied the OSCM method under a subbandgap photonic excitation to MOS systems with a poly-Si gate and verified a U-shaped distribution of interface trap density D<SUB>it</SUB>=10<SUP>10</SUP>∼10<SUP>12</SUP> eV<SUP>-1</SUP>cm<SUP>-2</SUP> for n- and p-type MOSFETs with W/L=30 μm/1.2 μm.

Observation of a d-wave gap in electron-doped Sr₂IrO₄

Kim, Y. K.,Sung, N. H.,Denlinger, J. D.,Kim, B. J. NATURE PUBLISHING GROUP 2016 NATURE PHYSICS Vol.12 No.1

<P>High-temperature superconductivity in cuprates emerges out of a highly enigmatic 'pseudogap' metal phase. The mechanism of high-temperature superconductivity is probably encrypted in the elusive relationship between the two phases, which spectroscopically is manifested as Fermi arcs-disconnected segments of zero-energy states-collapsing into d-wave point nodes upon entering the superconducting phase. Here, we reproduce this distinct cuprate phenomenology in the 5d transition-metal oxide Sr2IrO4. Using angle-resolved photo-emission, we show that the clean, low-temperature phase of 6-8% electron-doped Sr2IrO4 has gapless excitations only at four isolated points in the Brillouin zone, with a predominant d-wave symmetry of the gap. Our work thus establishes a connection between the low-temperature d-wave instability and the previously reported high-temperature Fermi arcs in electron-doped Sr2IrO4 (ref. 1). Although the physical origin of the d-wave gap remains to be understood, Sr2IrO4 is the first non-cuprate material to spectroscopically reproduce the complete phenomenology of the cuprates, thus offering a new material platform to investigate the relationship between the pseudogap and the d-wave gap.</P>

Validation of the metabolic pathway of the alginate-derived monomer in Saccharophagus degradans 2-40^T by gas chromatography-mass spectrometry

Kim, D.H.,Wang, D.,Yun, E.J.,Kim, S.,Kim, S.R.,Kim, K.H. Elsevier Applied Science 2016 Process biochemistry Vol.51 No.10

Marine macroalgae are potential resources for the sustainable production of biofuels and bio-based chemicals. Alginate, a major component of brown macroalgae, consists of two uronate monomers, which are further non-enzymatically converted to 4-deoxy-l-erythro-5-hexoseulose uronate (DEH). In several marine bacteria, DEH is known to be metabolized via three enzymatic steps, consisting of DEH reductase, 2-keto-3-deoxy-d-gluconate (KDG) kinase, and 2-keto-3-deoxy-phosphogluconate (KDPG) aldolase, which yields two glycolytic intermediates: d-glyceraldehyde-3-phosphate and pyruvate. However, such functions of these enzymes for the DEH pathway have rarely been experimentally validated. In the present study, the DEH metabolic pathway was investigated in Saccharophagus degradans 2-40<SUP>T</SUP>, a marine bacterium that utilizes alginate. Through in vitro tests assisted by gas chromatography/mass spectrometry and gas chromatography/time-of-flight mass spectrometry, the purified enzymes were functionally confirmed and annotated as dehR, kdgK, and kdpgA, respectively. In conclusion, we report the in vitro validation of the metabolic pathway of DEH monomerized from alginate.