RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      • 좁혀본 항목

      • 좁혀본 항목 보기순서

        • 원문유무
        • 음성지원유무
        • 원문제공처
        • 등재정보
        • 학술지명
        • 주제분류
        • 발행연도
        • 작성언어
        • 저자

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • SCISCIESCOPUS

        Substrate specificity of a recombinant d-lyxose isomerase from Providencia stuartii for monosaccharides

        Kwon,,H.J.,Yeom,,S.J.,Park,,C.S.,Oh,,D.K. Society for Bioscience and Bioengineering, Japan ; 2010 Journal of bioscience and bioengineering Vol.110 No.1

        The specific activity and catalytic efficiency (k<SUB>cat</SUB>/K<SUB>m</SUB>) of the recombinant putative protein from Providencia stuartii was the highest for d-lyxose among the aldose substrates, indicating that it is a d-lyxose isomerase. Gel filtration analysis suggested that the native enzyme is a dimer with a molecular mass of 44 kDa. The maximal activity for d-lyxose isomerization was observed at pH 7.5 and 45 <SUP>o</SUP>C in the presence of 1 mM Mn<SUP>2+</SUP>. The enzyme exhibited high isomerization activity for aldose substrates with the C2 and C3 hydroxyl groups in the left-hand configuration, such as d-lyxose, d-mannose, l-ribose, d-talose, and l-allose (listed in decreasing order of activity). The enzyme exhibited the highest activity for d-xylulose among all pentoses and hexoses. Thus, d-lyxose was produced at 288 g/l from 500 g/l d-xylulose by d-lyxose isomerase at pH 7.5 and 45 <SUP>o</SUP>C for 2 h, with a conversion yield of 58 % and a volumetric productivity of 144 g l<SUP>-1</SUP> h<SUP>-1</SUP>. The observed k<SUB>cat</SUB>/K<SUB>m</SUB> (920 mM<SUP>-1</SUP> s<SUP>-1</SUP>) of P. stuartiid-lyxose isomerase for d-xylulose is higher than any of the k<SUB>cat</SUB>/K<SUB>m</SUB> values previously reported for sugar and sugar phosphate isomerases with monosaccharide substrates. These results suggest that the enzyme will be useful as an industrial producer of d-lyxose.

      • SCISCIESCOPUS

        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>

      • SCISCIESCOPUS

        Solar polarimetry in the K I <i>D</i><sub>2</sub> line : A novel possibility for a stratospheric balloon

        Quintero,Noda,,C.,Villanueva,,G.,L.,Katsukawa,,Y.,Solanki,,S.,K.,Orozco,Suá,rez,,D.,Ruiz,Cobo,,B.,Shimizu,,T.,Oba,,T.,Kubo,,M.,Anan,,T.,Ichimoto,,K.,Suematsu,,Y. Springer-Verlag 2018 Astronomy and astrophysics Vol.610 No.-

        <P>Of the two solar lines, K I<I>D</I>1 and <I>D</I>2, almost all attention so far has been devoted to the <I>D</I>1 line, as <I>D</I>2 is severely affected by an O2 atmospheric band. This, however, makes the latter appealing for balloon and space observations from above (most of) the Earth’s atmosphere. We estimate the residual effect of the O2 band on the K I<I>D</I>2 line at altitudes typical for stratospheric balloons. Our aim is to study the feasibility of observing the 770 nm window. Specifically, this paper serves as a preparation for the third flight of the Sunrise balloon-borne observatory. The results indicate that the absorption by O2 is still present, albeit much weaker, at the expected balloon altitude. We applied the obtained O2 transmittance to K I<I>D</I>2 synthetic polarimetric spectra and found that in the absence of line-of-sight motions, the residual O2 has a negligible effect on the K I<I>D</I>2 line. On the other hand, for Doppler-shifted K I<I>D</I>2 data, the residual O2 might alter the shape of the Stokes profiles. However, the residual O2 absorption is sufficiently weak at stratospheric levels that it can be divided out if appropriate measurements are made, something that is impossible at ground level. Therefore, for the first time with Sunrise III, we will be able to perform polarimetric observations of the K I<I>D</I>2 line and, consequently, we will have improved access to the thermodynamics and magnetic properties of the upper photosphere from observations of the K I lines.</P>

      • Na+K-Cl 비율과 칼슘의 수준이 육계(肉鷄)의 능력 및 칼슘의 이용성, 혈액내 산염기(酸鹽基) 균형지수에 미치는 영향 : (1) Na+K-Cl 비율과 칼슘의 수준에 따른 육계(肉鷄)의 능력 (1) EFFECT OF Na+K-Cl RATIO AND CALCIUM LEVEL ON GROWTH PERFORMANCE IN BROILER CHICKS

        한인규,하종규,이학림,김대성 한국영양사료학회 1988 韓國營養飼料學會誌 Vol.12 No.3

        Na+K-Cl 비율과 Ca수준에 따른 Ca의 이용성 및 성장성적을 연구하기 위하여 두수준의 Ca(1.95%,1.20%) 와 네가지 수준의 사료전해질(0,150,370,450mEq/㎏)을 두어 2×4요인 배치로 실험을 실시하였다. 총252마리의 3일령 하이섹스 하이브로 병아리에게 28일간 실험사료를 급여하였으며 본실험에서 얻은 결과를 요약하면 아래와 같다. 1. 증체량은 Na+K-Cl 비율에 따라 차이를 보였으나 (P<0.05) Ca 첨가에 의한 영향은 나타나지 않았고 Ca과 Na+K-Cl 비율변화에 따라 유의적인 영향을 받았다 (P<00.01). Ca와 Na+K-G 비율의 상호작용은 서로 유의차를 보이지 않았다. 2. 사료섭취량은 Ca 첨가에는 무관하였으나, Na+K-Cl 비율변화에 따라 유의적인 영향을 받았다. (P<0.01). Ca와 Na+K-Cl 비율의 상호작용은 서로 유의차를 보이지 않았다. 3. Ca 첨가는 사료효율에는 영향을 미치지 않았고, Na+K-Cl 비율은 사료효율에 영향을 미쳤다(P<0.01). 4. Na+K-Cl 비율은 폐사율에 영향을 미쳤으나(P< 0.01), Ca 첨가와 두요인의 상호작용은 유의차를 보이지 않았다. 그러나 Na+K-Cl 비율이 높을 때 (450mEq/㎏)에는 폐사율이 높았다. 5. DM이용성은 Ca첨가에는 영향을 받았으나 (P<0.05), Na+K-Cl 비율과는 관계가 없었고, 두요인의 상호작용도 나타나지 않았다. N 축적과 Ca 축적은 Na+K-Cl 비율에 의해 영향을 받았고 (P<0.05), Ca 첨가에 의해서도 영향이 있었다 (P<0.01). An experiment was conducted with a 2 × 4 factorial arrangement in order to study the effect of sodium plus potassium to chloride ratio and calcium level on calcium availability and growth performance. The dietary treatments consisted of two levels of calcium (1.95% and 1.20%) and four levels of dietary electrolyte (0,150, 300, 450 mEq/㎏ in feed). A total number of 252 broiler chicks (3 days old Hisex-Hibro commercial chick) were fed the experimental diets for a period of 28 days. The results obtained in the present study are summarized as follow: 1. Body weight gain was markedly influenced by the level of sodium plus potassium to chloride ratio (p <0.01), but dietary level of calcium with electrolyte was not significant. 2. Feed intake was influenced by the level of sodium plus potassium to chloride ratio (p<0.01). 3. Dietary calcium levels did not affect the feed efficiency (p>0.05), but effect of sodium plus potassium to chloride ratio was highly significant (p < 0.01). 4. The simple effect of sodium plus potassium to chloride ratio markedly influenced the mortality (p < 0.01), but level of calcium did not affect mortality (p > 0.05). Interaction of calcium with electrolyte was not significant. High mortality was observed in the bird fed diet containing sodium bicarbonate (450 mEq/㎏). 5. Dry matter utilizability was influenced by dietary level of calcium (p <0.05), but no significant differences were observed by levels of electrolyte and interaction of calcium with electrolyte. Nitrogen retention and calcium retention were influenced by levels of electrolyte (p < 0.05) and levels of calcium (p < 0.01).

      • KCI등재SCOPUS

        Hurwitz type results for sums of squares and sums of triangular numbers

        D.,D.,Somashekara,K.,N.,VIDYA 장전수학회 2019 Advanced Studies in Contemporary Mathematics Vol.29 No.4

        Let rk(n) denote the number of representations of n as a sum of k squares and tk(n) denote the number of representations of n as a sum of k triangular numbers. Let r,(n) denote the number of representations of n as a sum of times a square and times another square and t,(n) denote the number of representations of n as a sum of times a triangular number and times another triangular number. We prove a number of results in which the generating function of r2(2k(an + b)), r4(2k(an + b)), r1,3(2k(an + b)), t2(2k(an + b)), t1,2(2k(an + b)), for various integer values of k, a and b, is a simple infinite product. We also obtain a relation between t1,3(3k+1n + 3k + 3k−1 · · · +3 + 1) and t1,3(n).

      • 인공지능을 이용한 3D 콘텐츠 기술 동향 및 향후 전망

        이승욱,황본우,임성재,윤승욱,김태준,김기남,김대희,박창준,Lee,,S.W.,Hwang,,B.W.,Lim,,S.J.,Yoon,,S.U.,Kim,,T.J.,Kim,,K.N.,Kim,,D.H,Park,,C.J. 한국전자통신연구원 2019 전자통신동향분석 Vol.34 No.4

        Recent technological advances in three-dimensional (3D) sensing devices and machine learning such as deep leaning has enabled data-driven 3D applications. Research on artificial intelligence has developed for the past few years and 3D deep learning has been introduced. This is the result of the availability of high-quality big data, increases in computing power, and development of new algorithms; before the introduction of 3D deep leaning, the main targets for deep learning were one-dimensional (1D) audio files and two-dimensional (2D) images. The research field of deep leaning has extended from discriminative models such as classification/segmentation/reconstruction models to generative models such as those including style transfer and generation of non-existing data. Unlike 2D learning, it is not easy to acquire 3D learning data. Although low-cost 3D data acquisition sensors have become increasingly popular owing to advances in 3D vision technology, the generation/acquisition of 3D data is still very difficult. Even if 3D data can be acquired, post-processing remains a significant problem. Moreover, it is not easy to directly apply existing network models such as convolution networks owing to the various ways in which 3D data is represented. In this paper, we summarize technological trends in AI-based 3D content generation.

      • 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>

      • Substrate specificity of a recombinant <small>D</small>-lyxose isomerase from <i>Serratia proteamaculans</i> that produces <small>D</small>-lyxose and <small>D</small>-mannose

        Park,,C.-S.,Yeom,,S.-J.,Lim,,Y.-R.,Kim,,Y.-S.,Oh,,D.-K. Blackwell Publishing Ltd 2010 Letters in applied microbiology Vol.51 No.3

        <P>Abstract</P><P>Aims: </P><P>Characterization of substrate specificity of a <SMALL>D</SMALL>-lyxose isomerase from <I>Serratia proteamaculans</I> and application of the enzyme in the production of <SMALL>D</SMALL>-lyxose and <SMALL>D</SMALL>-mannose.</P><P>Methods and Results: </P><P>The concentrations of monosaccharides were determined using a Bio-LC system. The activity of the recombinant protein from <I>Ser. proteamaculans</I> was the highest for <SMALL>D</SMALL>-lyxose among aldoses, indicating that it is a <SMALL>D-</SMALL>lyxose isomerase. The native recombinant enzyme existed as a 54-kDa dimer, and the maximal activity for <SMALL>D-</SMALL>lyxose isomerization was observed at pH 7·5 and 40°C in the presence of 1 mmol l<SUP>−1</SUP> Mn<SUP>2+</SUP>. The <I>K</I><SUB>m</SUB> values for <SMALL>D</SMALL>-lyxose, <SMALL>D</SMALL>-mannose, <SMALL>D</SMALL>-xylulose, and <SMALL>D</SMALL>-fructose were 13·3, 32·2, 3·83, and 19·4 mmol l<SUP>−1</SUP>, respectively. In 2 ml of reaction volume at pH 7·5 and 35°C, <SMALL>D</SMALL>-lyxose was produced at 35% (w/v) from 50% (w/v) <SMALL>D</SMALL>-xylulose by the <SMALL>D-</SMALL>lyxose isomerase in 3 h, while <SMALL>D</SMALL>-mannose were produced at 10% (w/v) from 50% (w/v) <SMALL>D</SMALL>-fructose in 5 h.</P><P>Conclusions: </P><P>We identified the putative sugar isomerase from <I>Ser. proteamaculans</I> as a <SMALL>D</SMALL>-lyxose isomerase. The enzyme exhibited isomerization activity for aldose substrates with the C2 and C3 hydroxyl groups in the left-hand configuration. High production rates of <SMALL>D-</SMALL>lyxose and <SMALL>D</SMALL>-mannose by the enzyme were obtained.</P><P>Significance and Impact of the Study: </P><P>A new <SMALL>D-</SMALL>lyxose isomerase was found, and this enzyme had higher activity for <SMALL>D</SMALL>-lyxose and <SMALL>D</SMALL>-mannose than previously reported enzymes. Thus, the enzyme can be applied in industrial production of <SMALL>D</SMALL>-lyxose and <SMALL>D</SMALL>-mannose.</P>

      • SCOPUSKCI등재

        EFFECTS OF ACUTE AND SUBACUTE ADMINISTRATION OF COCAINE ON DOPAMINERGIC SYSTEMS IN THE RAT STRIATUM

        Lim,,D.K.,Ho,,I.K. The Korean Society of Toxicology Korea Environment 1990 Toxicological Research Vol.6 No.1

        The characteristics of dopamine uptake, D-1 and D-2 receptors after acute and subacute cocaine administration were determind in striatum from WKY and SHR. Cocaine was administered either acutely (40 mg/kg, s.c.) or twice daily (20 mg/kg, s.c.) for 3 and 7 days in 9-wk old WKY and SHR. Rats were sacrificed 30 min, 2 or 24 h after the single injection and 18 h after the last administration to the subacutely treated group. The changes in dopamine uptake, dopamine uptake sites, D-1 and D-2 receptors were determined using $(^3H)$dopamine, $(^3H)$-GBR-12935, $(^3H)$SCH-23390 and $(^3H)$sulpiride, respectively. In acutely treated rats, significant increases in $V_{max}$of dopamine uptake were observed 30 min after the cocanine injection in both strains without changes in $K_m$ values. The in vitro $IC_{50}$for cocaine was significantly decreased 30 min in WKY and 2 h in SHR. However, that for in vitro GBR-12909 was significantly increased 30 min and 2 h in both strains. Also densities of $(^3H)$-GBR-12935 binding sites were significantly increased 30 min and 2 h without changes in their $K_d$. Significant increases in D-2 receptor density were observed 30 min, 2 or 24 h after acute injection in both strains without changes in their affinities. The density of D-1 receptor was significantly decreased 30 min after the injection in WKY, but not in SHR. In subacutely treated rats, a significant increase in $K_m$ of dopamine uptake was observed in 7-day treated SHR. The in vitro $IC_{50}$fot GBR-12909 was significantly increased in 3-day treated WKY. The density of D-1 receptors was significantly increased in 3- and 7-day treated WKY, but not in SHR. The affinity of both binding sites remained unchanged. The results suggest that cocanine administration alters dopamine uptake, characteristics of dopamine uptake sites and dopamine receptor binding characteristics in rat brain. Furthermore, D-1 and D-2 dopamine receptors appear to be differently regulated.

      • KCI우수등재

        재래한우의 보존을 위한 혈청 및 혈구단백질의 유전적 다형현상

        한상기,신유철,윤희섭,정의룡,변희대 한국축산학회 1995 한국축산학회지 Vol.37 No.1

        Biochemical polymorphisms of five red cell and semen proteins, Hemoglobin(Hb), Transferrin(Tf), Post-transferrin 2(Ptf2), Post-albumin(Pa) and Albumin(Alb) as genetic markers in Korean cattle were analyzed by Starch and Polyacryamide gel electrophoresis and their phenotypes, genotypes and gene frequencies were estimated in order to analysis the genetic constitution of Korean native cattle population. In the Hemoglobin(Hb) locus four different phenotypes AA, AB, BB and CH were observed and assumed to be controlled by four different alleles designated Hb^A, Hb^B, Hb^C and Hb^H, and the Hb^H type was rare variant of Korean native cattle. The observed distribution of phenotypes were 73.37% for AA type, 23.37% for AB type. 2.72% for BB type and 0.54%r for CH type. Gene frequencies of Hb^A, Hb^B, Hb^C and Hb^H were 0.8505, 0.1440, 0.0027 and 0.0027. Semen Transfetrin(Tf) locus, 11 different phenotypes AA, AD₁, AD₂, AE, AH, D₁D₁, D₁D₂, D₁E, D₂H, D₂D₂, D₂E, EE and EH type were identified, which considered to be controlled by codominant alleles TF,^A Tf^D, Tf^D, Tf^E and Tf^H at a single locus. The frequencies of Tf genotypes AD₁, D₁E, D₁D₂, D₂E, AA, AE, D₁D₂, AD₂, D₁D₁, EE, AH, D₂H and EH were found to be 16.30, 13.33, 11.85, 10.37, 9.69, 8.15, 7.41, 9.63, 5.93, 4.44, 1.48, 0.74 and 0.01%, respectively. Gene frequencies of TF^A, Tf^(D1) Tf^(D2) and Tf^H were 0.2741, 0.2704, 0,2333, 0.2074 and 0.0148, respectively. And TfH gene were newly identified in Korean native cattle. Considering Post-transterrin 2 locus, three different phenotypess FF, FS and SS were identified, which considers to he controlled by two alleles Ptf^F and Ptf^S at a single autosomal locus. The frequencies of Rf genotypes FS, FF and SS were found to be 51.06. 36.88 and 12.06%n, respectively and gene frequencies of Ptf^F and Ptf^S were 0.6241 and 0.3759. In the Postalbumin(Pa) locus, three different phenotypes FF, FS and SS type were observed to be genetically controllled by Pa^F and Pa^S gene. And genotypes frequencies FS. FF amd SS type were 48.65, 36.(H and 1_5.32%, respectively. The gene frequencies of Pa^F and Pa^S were 0.6036 and 0.3964. The Albumin(Alb) locus were observed to lack any individual variation. Therefore, this locus were defined to be monomorphic. In comparison of genetic distance and dendogram calculated from the gene frequencies, close relationship was obtained between the Japanese cattle and the Korean cattle.

      맨 위로 스크롤 이동