Saccharomyces cerevisiae Live Cells Decreased In vitro Methane Production in Intestinal Content of Pigs

Gong, Y.L.,Liao, X.D.,Liang, J.B.,Jahromi, M.F.,Wang, H.,Cao, Z.,Wu, Y.B. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.6

An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane ($CH_4$) production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress $CH_4$ production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells), control (no live yeast cells) and yeast (YST) supplementation groups (supplemented with live yeast cells, YST1 or YST2). The yeast cultures contained $1.8{\times}10^{10}$ cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc${\times}$Landrace${\times}$Yorkshire pigs, mixed with a phosphate buffer (1:2), and incubated anaerobically at $39^{\circ}C$ for 24 h using 500 mg substrate (dry matter (DM) basis). Total gas and $CH_4$ production decreased (p<0.05) with supplementation of yeast. The methane production reduction potential (MRP) was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD) and total volatile fatty acids (VFA) concentration increased (p<0.05) in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05), but that of acetate decreased (p<0.05), which led to a decreased (p<0.05) acetate: propionate (A: P) ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05) with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05) with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro $CH_4$ production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic bacteria, both of which serve as a competitive pathway for the available H2 resulting in the reduction of methanogenic archaea.

X-band용 Ni₂Y/Rubber 복합형흡수체의 정합조건설계

사공건,신광호,김한근 동아대학교 공과대학 부설 한국자원개발연구소 1995 硏究報告 Vol.19 No.2

The absorption properties of ferroxplana/rubber composite microwave absorbers were evaluated. The composite specimens have prepared by molding and curing the mixtures of matrix rubber and ferroxplana ferrite powders used as a filler particle which were synthesized by the coprecipitation method using BaCl₂·2H₂O, NiCl₂·6H₂O and FeCl₃·6H₂O. We have figured out the matching conditions of the Ni₂Y ferroxplana/rubber composite specimens from the impedance matching map and boundary map. On the composite specimens, we have found that the reflection losses were larger than 20[dB] from 8.7 to 10.9[GHz]. As a results, the Ni₂Y/rubber composite absorber would be applied for x-band frequency applications.

다이아몬드 휠에 의한 세라믹 연삭의 연삭력 평가

문홍현,김성청,공재향,박병규,소의열,이근상 한국공작기계학회 2002 한국공작기계학회 춘계학술대회논문집 Vol.2002 No.-

In this study, through the experimental results of grinding ratio, grinding force and surface roughness with the obtained wear amount of diamond wheel and ceramic material during the grinding process, the following conclusions could be found. In the case of Si₃N₄, the wear of diamond wheel is large while the grinding force is stable and the range of change in surface roughness is small. For the case of Al₂O₃ and ZrO₂, while the wear of diamond wheel is getting smaller, the grinding force is increasing but the value of surface roughness is decreasing. For grinding with the vitrified bond wheel, it seems that the self-sharpening can be found for Si₃N₄ and the glazing effect of the cutting edge for Al₂O₃ and ZrO₂.

Development of Continuous Galvanization-compatible Martensitic Steel

( Y. F. Gong ),( T J. Song ),( Han S. Kim ),( J H Kwak ),( B. C De Cooman ) 한국부식방식학회(구 한국부식학회) 2012 Corrosion Science and Technology Vol.11 No.1

The development of martensitic grades which can be processed in continuous galvanizing lines requires the reduction of the oxides formed on the steel during the hot dip process. This reduction mechanism was investigated in detail by means of High Resolution Transmission Electron Microscopy (HR-TEM) of cross-sectional samples. Annealing of a martensitic steel in a 10% H2 + N2 atmosphere with the dew point of-35˚C resulted in the formation of a thin c-xMnO.Si02 (x>l) oxide film and amorphous a-xMnO.SiO2 oxide particles on the surface. During the hot dip galvanizing in Zn-0.13%Al, the thin c-xMnO.SiO2 (x>1) oxide film was reduced by the Al. The a-xMnO.SiO2 (x<0.9) and a-S102 oxides however remained embedded in the Zn coating close to the steel/coating interface. No Fe2AIZn inhibition layer formation was observed. During hot dip galvanizing in Zn-0.20%AI, the c-xMnO.Si02 (x>l) oxide film was also reduced and the amorphous a-xMnO.SiO2, and a-SiO2 particles were embedded in the Fe2M5Zn inhibition layer formed at the steel/coating interface during hot dipping. The results clearly show that Al in the liquid Zn bath can reduce the crystalline c-xMn, SiO2 (x>l) oxides but not the amorphous a-xMnO.SiO2 (x<0.9) and a-Si02 oxides. These oxides remain embedded in the Zn layer or in the inhibition layer, making it possible to apply a Zn or Zn-alloy coating on martensitic steel by hot dipping. The hot dipping process was also found to deteriorate the mechanical properties, independently of the Zn bath composition.

CoZrNb막을 이용한 MI센서 소자의 제작 및 특성

허진,김영학,신광호,사공건,Hur, J.,Kim, Y.H.,Shin, K.H.,Sa-Gong, G. 한국전기전자재료학회 2004 전기전자재료학회논문지 Vol.17 No.1

Magneto-Impedance(MI) sensor is a highly sensitive sensor, which was able to detect a weak geomagnetic field. It also has a merit to be able to build in the low power system. In this study, their magnetic permeability and anisotropy field(H$\sub$k/) as a function of some different thickness of sputtered amorphous CoZrNb films with zero-magnetostriction and soft magnetic property are investigated. In order to make a uniaxial anisotropy, film was subjected to the post annealing in a static magnetic field with 1KOe intensity at 250, 300, and 320$^{\circ}C$ respectively for 2 hours. Magnetic properties of films are measured by using a M-H loop tracer. Magnetic permeability of a film is measured over the frequency range from 1 ㎒ to 750㎒. By thickening a CoZrNb film relatively, magnetic permeability and impedance are examine to design the. MI sensor which drives at 50㎒, and thereof fabricated the MI sensor which drives at the 50㎒.

융모성 질환의 임상적 고찰

공지원,정두수,이승철,정은신,이형열,이영혜 예수병원 1992 예수병원학술지 Vol.13 No.-

대규모 원단 도매 시장에서의 포름알데히드 노출에 관한 연구

최상준,백남원,김지현,이미선,황정희,정현희,이은희,최연기,양윤정,이태범,이경민,공정옥,이영미 서울대학교 보건대학원 2001 서울大學校 保健環境硏究所論叢 Vol.11 No.1

This study was conducted to assessment airborne formaldehyde concentration at dry-goods stores, 'G' market and additionally at the reconstructed lecture room in the university during November, 2001. 'NIOSH 2016' method, with 2,4-DNPH treated silica gel sampler and HPLC, was used for sampling and analysis of formaldehyde concentration. Because every merchant rejects to participate in study, volunteers, pretend to customer, were involved to monitor personal exposure level. The results are summarized as follows ; 1. The geometric mean(GM) and geometric standard deviation(GSD) of TWA concentrations from 'G' market were 0.037 ppm and 2.17 respectively. 2. The TWA concentrations of the personal samples from 'G' market ranged from 0.009 to 0.065 ppm and those of the area samples from '' market ranged from 0.06 to 0.071 ppm. 3. The TWA concentrations of the area samples from reconstructed lecture room ranged from 0.022 to 0.094 ppm. The TWA concentration from latest reconstructed lecture room was higher than that of older reconstructed lecture room. 4. All of samples except one were exceeding NIOSH TWA criteria, 0.016 ppm.

Prognostic and predictive values of EGFR overexpression and <i>EGFR</i> copy number alteration in HER2-positive breast cancer

Lee, H J,Seo, A N,Kim, E J,Jang, M H,Kim, Y J,Kim, J H,Kim, S-W,Ryu, H S,Park, I A,Im, S-A,Gong, G,Jung, K H,Kim, H J,Park, S Y Nature Publishing Group 2015 The British journal of cancer Vol. No.

<P><B>Background:</B></P><P>Epidermal growth factor receptor (EGFR) is overexpressed in a subset of human epidermal growth factor receptor 2 (HER2)-positive breast cancers, and coexpression of HER2 and EGFR has been reported to be associated with poor clinical outcome. Moreover, interaction between HER2 and EGFR has been suggested to be a possible basis for trastuzumab resistance.</P><P><B>Methods:</B></P><P>We analysed the clinical significance of EGFR overexpression and <I>EGFR</I> gene copy number alterations in 242 HER2-positive primary breast cancers. In addition, we examined the correlations between EGFR overexpression, trastuzumab response and clinical outcome in 447 primary, and 112 metastatic HER2-positive breast cancer patients treated by trastuzumab.</P><P><B>Results:</B></P><P>Of the 242 primary cases, the level of EGFR overexpression was 2+ in 12.7% and 3+ in 11.8%. High <I>EGFR</I> gene copy number was detected in 10.3%. Epidermal growth factor receptor overexpression was associated with hormone receptor negativity and high Ki-67 proliferation index. In survival analyses, EGFR overexpression, but not high <I>EGFR</I> copy number, was associated with poor disease-free survival in all patients, and in the subgroup not receiving adjuvant trastuzumab. In 447 HER2-positive primary breast cancer patients treated with adjuvant trastuzumab, EGFR overexpression was also an independent poor prognostic factor. However, EGFR overexpression was not associated with trastuzumab response, progression-free survival or overall survival in the metastatic setting.</P><P><B>Conclusions:</B></P><P>Epidermal growth factor receptor overexpression, but not high <I>EGFR</I> copy number, is a poor prognostic factor in HER2-positive primary breast cancer. Epidermal growth factor receptor overexpression is a predictive factor for trastuzumab response in HER2-positive primary breast cancer, but not in metastatic breast cancer.</P>

Post annealing effect of flexible polymer solar cells to improve their electrical properties

Gong, S.C.,Jang, S.K.,Ryu, S.O.,Jeon, H.,Park, H.H.,Chang, H.J. Elsevier 2010 CURRENT APPLIED PHYSICS Vol.10 No.4

Flexible polymer solar cells with an ITO/PEDOT/P3HT:PCBM/Al structure were fabricated using regioregular poly(3-hexylthiophene) (P3TH) polymer:(6,6)-phenyl C61-butyric acid methyl ester (PCBM) fullerene polymer as the photovoltaic (PV) bulk hetero-junction layer. The P3HT and PCBM used as the electron donor and electron acceptor materials were spin cast on indium tin oxide (ITO) coated polyethylene naphthalate (PEN) substrates. The optimum mixing concentration ratio of the P3HT:PCBM PV layer was found to be 4:4 wt.%, at which the maximum short circuit current density (J<SUB>SC</SUB>), open circuit voltage (V<SUB>OC</SUB>), fill factor (FF) and power conversion efficiency (PCE) values were about 3.8 mA/cm<SUP>2</SUP>, 427 mV, 36.6% and 0.66%, respectively. To investigate the effects of the post annealing treatment, the as-prepared flexible polymer solar cells were post annealed at temperatures ranging from 150 <SUP>o</SUP>C to 180 <SUP>o</SUP>C for 5 min. The J<SUB>SC</SUB> and V<SUB>OC</SUB> values increased with increasing post annealing temperature from 150 <SUP>o</SUP>C to 170 <SUP>o</SUP>C, which may be due to the improvement of the light absorption coefficient of P3HT and improved ohmic contact between the PV layer and Al electrode film. The maximum J<SUB>SC</SUB>, V<SUB>OC</SUB>, FF and PCE values of the flexible polymer solar cell, which was post annealed at 170 <SUP>o</SUP>C for 5 min, were found to be about 4.3 mA/cm<SUP>2</SUP>, 616 mV, 32.6% and 0.86%, respectively.

Combined treatment with vitamin C and sulindac synergistically induces p53- and ROS-dependent apoptosis in human colon cancer cells

Gong, E.Y.,Shin, Y.J.,Hwang, I.Y.,Kim, J.H.,Kim, S.M.,Moon, J.H.,Shin, J.S.,Lee, D.H.,Hur, D.Y.,Jin, D.H.,Hong, S.W.,Lee, W.K.,Lee, W.J. Elsevier/North-Holland 2016 Toxicology letters Vol.258 No.-

Sulindac has anti-neoplastic properties against colorectal cancers; however, its use as a chemopreventive agent has been limited due to toxicity and efficacy concerns. Combinatorial treatment of colorectal cancers has been attempted to maximize anti-cancer efficacy with minimal side effects by administrating NSAIDs in combination with other inhibitory compounds or drugs such as l-ascorbic acid (vitamin C), which is known to exhibit cytotoxicity towards various cancer cells at high concentrations. In this study, we evaluated a combinatorial strategy utilizing sulindac and vitamin C. The death of HCT116 cells upon combination therapy occurred via a p53-mediated mechanism. The combination therapeutic resistance developed in isogenic p53 null HCT116 cells and siRNA-mediated p53 knockdown HCT116 cells, but the exogenous expression of p53 in p53 null isogenic cells resulted in the induction of cell death. In addition, we investigated an increased level of intracellular ROS (reactive oxygen species), which was preceded by p53 activation. The expression level of PUMA (p53-upregulated modulator of apoptosis), but not Bim, was significantly increased in HCT116 cells in response to the combination treatment. Taken together, our results demonstrate that combination therapy with sulindac and vitamin C could be a novel anti-cancer therapeutic strategy for p53 wild type colon cancers.