• Title/Summary/Keyword: HBL

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Amino Acid Concentrations in the Blastocoelic Fluid of In Vitro-Produced Bovine Blastocysts (체외생산된 소 배반포강 내의 아미노산 농도)

  • Jung, Y.G.;Wei, H.;Yoon, J.T.;Fukui, Y.
    • Journal of Embryo Transfer
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    • v.13 no.3
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    • pp.251-259
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    • 1998
  • Concentrations of free amino acids in the BF of IVP bovine BL and HBL were examined in this study. The embryos derived from IVF oocytes were cultured in a SOFM containing BSA, EAA and NEAA. BF was aspirated from BL (180 h of age after insemination) and HBL (216 h of age after insemination), and introduced into drops of SOFM (30$\mu$l/drop) containing PVA through micromanipulation. The medium containing BF was then subjected to measurement of 20 amino acids by an automatic amino acid analyzer. The concentrations of isoleucine, leucine and methionine were higher (p〈0.05) in the BF from HBL than from BL, and no difference was found in aspartate or glutamate concentrations between BL and HBL, while threonine, alanine (p〈0.01) and the rest of the amino acids (p〈0.001) were significantly higher in the BF from HBL than from BL. Cystine was not found in either BL or HBL. A high concentration of glutamine was found in the BF from both BL and HBL, although it was not added to the culture medium. These results indicate that bovine BF contains several EAA (methionine in BL and isoleucine, leucine and methionine in HBL) and NEAA (alanine, glutamate, glycine, proline, serine and aspartate in BL, and glutamate and aspartate in HBL), and there is significant differences in the amino acid concentration in the BF between BL and HBL derived by WP.

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The Effect of Blocking Layer Design Variable on the Characteristics of GaN-based Light-Emitting Diode (차단층 설계 변수가 GaN 기반 LED 특성에 미치는 영향)

  • Lee, Jae-Hyun;Yeom, Keesoo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.10a
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    • pp.233-236
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    • 2012
  • In this paper, the output characteristics of GaN-based LED considering blocking layer design variables are analyzed. The basic structure of the LED consists of active region of GaN barrier and InGaN quantum well between AlGaN EBL(Electron Blocking Layer) and AlGaN HBL(Hole Blocking Layer) on GaN buffer layer. The output power, internal quantum efficiency characteristics of LED active region considering Al mole fraction of EBL, thickness of EBL, Al mole fraction of HBL and doping concentration of HBL are analyzed using ISE-TCAD.

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Toxin Gene Profiling of Bacillus cereus Food Isolates by PCR

  • Seong, Seon-Je;Lim, Ji-Su;Lee, Kwang-Geun;Lee, Seung-Ju;Hong, Kwang-Won
    • Applied Biological Chemistry
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    • v.51 no.4
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    • pp.263-268
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    • 2008
  • Seventy-one Bacillus cereus strains (12 references and 59 food isolates) were analyzed for the occurrence of five different enterotoxin genes (nheABC, hblCDA, entFM, cytK, and bceT) and one emetic toxin cereulide synthetase gene (ces) by PCR (polymerase chain reaction). PCR analysis revealed eight toxigenic patterns in all B. cereus strains tested; they all carried both entFM and nheABC. The presence of hblCDA, cytK, and bceT varied according to the enterotoxin-producing strains, among which hblCDA was the least frequently detected in the food-isolated strains. Only five B. cereus strains harbored ces, associated with the emetic type of food poisoning; however, these strains were devoid of hblCDA, cytK, and bceT.

Electrophosphorescent organic light-emitting diodes with modified hole blocking layer

  • Shin, Y.C.;Baek, H.I.;Lee, C.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1042-1045
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    • 2006
  • The electrical and optical properties of electrophosphorescent organic light-emitting diodes (OLEDs) with modified hole blocking layer (HBL) were investigated. Well-known 2,9-dimethyl-4,7- diphenyl-1,10-phenanthroline (BCP) HBL is mixed with electrophosphorescent host material (4,4'-N,N'- dicarbazole-biphenyl: CBP) or electrophosphorescent dopant material (fac-tris(2-phenylpyridine) iridium: $Ir(ppy)_3$) or both. The highest external quantum efficiency was obtained in the device with $BCP-CBP-Ir(ppy)_3$ mixed HBL and we attribute this result to the additional charge recombination in mixed-HBL.

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Homobrassinolide and chemical composition of curcuma longa L. (turmeric) rhizome

  • G, Rajesh;B.V. Vardhini
    • Advances in environmental research
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    • v.12 no.1
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    • pp.65-75
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    • 2023
  • The effect of homobrassinolide (HBL) on the nutrient value of Curcuma longa L. (turmeric) rhizome grown in Nizamabad, Telangana State, India was studied. Application of homobrassinolide (HBL) as foliar spray to turmeric plants on the 20th, 40th and 60th day from sowing resulted in enhanced chemical composition of turmeric rhizome. Application of homobrassinolide (HBL) resulted in enhanced total sugars, principal ingredient curcumin, total poly phenol content, total flavonoid content, total tannin content, crude fat, crude fibre and essential oils (turmerone, zingiberene, cineole and p-cymene) present in the turmeric rhizome indicating the ability of homobrassinolide (HBL) as a potential plant growth regulator (PGR).

Prevalence and Toxin Genes of Food-Borne Pathogens Isolated from Toothbrush in Child Care Center (보육시설 유아 사용 칫솔의 식중독 미생물 분포 및 독소 유전자)

  • Kim, Jong-Seung;Kim, Jung-Beom
    • Journal of Food Hygiene and Safety
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    • v.30 no.3
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    • pp.242-248
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    • 2015
  • This study was performed to investigate the microbiological contamination on toothbrushes, toothbrush caps, and tooth cleaning cups in the child care centers and to evaluate the toxin genes, toxin production ability and antibiotic resistance of food-borne pathogens. The average number of total aerobic bacteria and fungi were 5.3 log CFU and 3.2 log CFU. Coliform bacteria were detected in 41 (54.7%) of 75 toothbrushes, 13 (44.8%) of 29 toothbrush caps, and 29 (44.6%) of 65 tooth cleaning cups. Salmonella spp. was not detected in all of samples but Bacillus cereus was isolated from 1 (1.3%) of 75 toothbrushes and 2 (3.1%) of 65 tooth cleaning cups. Staphylococcus aureus was detected in 1 (1.5%) of 65 tooth cleaning cups. The nheA, nheB, nheC, hblC, hblD, hblA and entFM toxin genes were possessed in B. cereus isolated from toothbrush which also produce NHE and HBL enterotoxins. S. aureus was resistant to ampicillin and penicillin, while B. cereus was resistant to ${\beta}-lactam$ antibiotics. These results indicated that the sanitary conditions of toothbrushes and tooth cleaning cups in the child care centers should be improved promptly. The UV sterilization after drying and then storage in dried condition is required to improve the sanitary condition of toothbrushes and tooth cleaning cups in the child care center.

Prevalence and Toxin Characteristics of Microorganism on Hand Towels Using for Children in Child Care Center (보육시설 유아 사용 수건의 미생물 분포 및 독소 특성)

  • Kim, Jung-Beom;Kim, Nan-Yong;Kang, Suk-Ho;Do, Young-Sook;Eom, Mi-Na;Yoon, Mi-Hye;Lee, Jong-Bok
    • Journal of Food Hygiene and Safety
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    • v.28 no.2
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    • pp.138-145
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    • 2013
  • This study was conducted to evaluate the microbiological contamination on commonly used hand towels in the child care centers and to investigate the toxin gene and toxin production ability of food-borne pathogens. A total of 22 commonly used hand towels including 7 for before use and 15 for during use were tested. The average number of total aerobic bacteria and fungi were 6.2 log CFU/100 $cm^2$ and 4.1 log CFU/100 $cm^2$. Coliform bacteria were detected in 4 out of 7 before used towels (57.1%) and all of during used towels (100%). These results showed that the sanitary conditions of hand towels in the child care centers should be improved promptly. Among the pathogenic bacteria, Staph. aureus and B. cereus without Salmonella spp. were detected in 5 (22.7%) and 11 (50.0%) out of 22 hand towels. All of Staphy. aureus isolated in this study did not possess any toxin genes and did not produce enterotoxin. The detection rate of hblC, hblD, and hblA toxin genes in B. cereus was 72.7, 72.7, and 54.5% respectively. The possession rate of nheA, nheB, and nheC toxin genes showed 81.8, 72.7, and 54.5% respectively. The cytK and entFM toxin genes were presented at 45.5 and 90.0% in B. cereus. The HBL was detected in 8 out of 11 B. cereus isolates (72.7%) and 5 B. cereus isolates produced NHE (45.5%). Ten out of eleven B. cereus isolates (90.9%) produced one or more enterotoxin such as HBL and NHE. From the results, using a private hand towel or paper towel is required to prevent the cross-contamination between commonly used hand towel and children's hands in the child care center.

Molecular Characterization and Toxin Profile of Bacillus cereus Strains Isolated from Ready-to-eat Foods (유통 중인 즉석·편의식품류에서 분리한 Bacillus cereus의 산생 Toxin 및 분자유전학적 특성 조사)

  • Kim, Tae Sun;Kim, Min Ji;Kang, Yu Mi;Oh, Geune;Choi, Su Yeon;Oh, Mu Sul;Yang, Yong Shik;Seo, Jung-Mi;Ryu, Mi-Geum;Kim, Eun-Sun;Ha, Dong-Ryong;Cho, Bae Sik
    • Korean Journal of Food Science and Technology
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    • v.46 no.3
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    • pp.334-340
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    • 2014
  • Toxin-producing Bacillus cereus is the causative agent of two different types of food poisoning: the emetic and the diarrheal types. This study was conducted to investigate the presence of enterotoxin and emetic toxin genes in 263 B. cereus isolated from 619 different ready-to-eat food items. Hemolytic enterotoxins hblA, hblC, and hblD were detected in 85.6, 41.1, and 76.8%, respectively, of the B. cereus isolates. About 67.0% (175/263) of the isolates presented all of three genes. Non-hemolytic enterotoxins nheA, nheB, and nheC were detected in 100, 97.0, and 68.4% of the isolates, respectively. Approximately 90.0% (236/263) of the isolates presented all of these three non-hemolytic enterotoxin genes. Emetic toxin gene, CER, was detected in 132 of 263 (50.2%) isolates. Computer-assisted cluster analysis of Rep-PCR profiles showed a high genetic diversity among the isolates. All B. cereus isolates from food samples tested in this study carried at least 6 of 10 toxin genes.

The Fabrication of OLED using PBD as a Hole Blocking Layer

  • Kang, Min-Woong;Kim, Jong-Sung;Kwon, Sang-Jik;Lee, Hoo-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.784-787
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    • 2002
  • Oganic light emitting diodes (OLEDs) using PBD(2-(4-biphenylyl)-5-(4-tert-butylpheny)-1,3,4oxadiazole) as a hole blocking layer were fabricated and their device performances were investigated. The devices have a structure of glass substrate ${\setminus}$ indium tin oxide (ITO) ${\setminus}$ TPD(HTL)${\setminus}$PBD,BCP(HBL)${\setminus}$Alq3(EIL)${\setminus}$Mg:Ag(cathode). In this work Bathocuproine(BCP:2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline) and PBD which were previously known as a good ETL material were used as a HBL. By employing HBL, the luminance and quantum efficiency of OLEDs could be improved due to the increase of recombination probability of electrons and holes.

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New Hole Blocking Layer for low voltage and high efficiency OLEDs (New Hole Blocking Layer를 포함한 OLEDs)

  • Ha, Mi-Young;Kim, So-Youn;Moon, Dae-Gyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.442-443
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    • 2007
  • We have studied new hole blocking layer for effective organic light emitting diodes. The device having a structure of ITO/2TNATA/$\alpha$-NPD/DPVBi : Rubrene(0.7%)/DPVBi/New Hole Blocking layer or BCP/$Alq_3$/LiF/Al has been used. The driving voltage of OLED with BCP(2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) or New HBL were 5.5V and 4.4V, respectively. As a result, new HBL rather than BCP has a good hole blocking ability.

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