• 제목/요약/키워드: $TbB_4$

검색결과 81건 처리시간 0.03초

비정질 TbFeCo 합금 증착박막의 자기광학효과 (Magneto-optic effect of thermal evaporated amorphous TbFeCo thin flim)

  • 박용관;양계준
    • E2M - 전기 전자와 첨단 소재
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    • 제5권4호
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    • pp.439-445
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    • 1992
  • 최근 광자기 기록매체로 주목받고 있는 RE-TM계 비정질 박막을 T $b_{x}$ (F $e_{0.9}$ $Co_{0.1}$)$_{100-x}$ (x=14, 17, 20, 23, 27[at%])의 조성비를 갖는 모합금을 만든후 진공증착방법으로 합금박막을 제작하였다. 각시료의 조성에 따른 자기광학효과를 알아보기 위하여 80K부터 600K에서 포화자화( $M_{s}$ )와 보자력( $H_{c}$)에 대한 온도의존성과 자기이방성상수(Ku), Polar Kerr 이력곡선을 측정하였다. 또한 Curie 온도 근처에서 열처리 시간에 따른 자기 토크 곡선의 변화를 분석 함으로써 합금박막 표면의 산화정도를 정성적으로 평가할 수 있었다. 실험결과 T $b_{22.72}$(F $e_{68.78}$ $Co_{8.5}$)인 시료가 상온에서 8.4KOe의 보자력을 가졌으며 T $b_{x}$(x=23[at%])인 경우가 가장 큰 수직자기이방성을 나타냈다. Polar Kerr 이력곡선은 Tb함량 x=25~26[at%]에서 부호가 반전됨을 알 수 있었다.다.다.다.

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Benzo[a]pyrene 대사체의 발암활성 영역 및 DNA 염기와의 분자착물의 배향 (The Carcinogenic Region of Benzo[a]pyrene Metabolites and Its Molecular Complex with Guanine and Adenine)

  • 김종문;손관수;도성탁;김석규;박병각
    • 대한화학회지
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    • 제40권4호
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    • pp.229-234
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    • 1996
  • Benzo[a]pyrene(BP)과 그들의 대사체들의 발암성을 PM3의 방법으로 조사하였다. BP분자내의 transbutadiene(TB)frame을 형성하는 4, 5, 5a, 그리고 6번 위치가 발암활성영역임을 LUMO 전자밀도로 예측하고 Ultimate carcinogen인 BP-triol의 발암활성영역이 10, 10a, 12c, 그리고12b 위치로 변화함을 알았다. TB 영역에 해당하는 Guanine의 HOMO와 BP-triol의 LUMO 사이의 전하이동량이 가장 큼을 알았다.

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소 결핵 진단을 위한 인터페론감마 검사 키트의 성능 비교 평가 (Performance comparison and evaluation of interferon-gamma assay kit for bovine tuberculosis diagnosis)

  • 홍이곤;최우재;노영혜;안선민;김은경;최은희;김단일
    • 한국동물위생학회지
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    • 제43권4호
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    • pp.201-209
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    • 2020
  • In Korea, bovine tuberculosis (bTB) is a representative zoonotic disease that causes considerable economic loss. In determining the positive bTB, the ELISA method for examining the amount of interferon-gamma (IFN-γ) is included in Korea's diagnostic standard method. Recently, commercially available BIONOTE TB-Feron ELISA Plus (TB-Feron Plus) that detects IFN-γ has been introduced. However, since the scientific basis for the performance is limited, we evaluated performance by comparing it with the results of another IFN-γ ELISA assay kit (BOVIGAM®) certified by Office International des Epizooties. In our research, 42 positive blood samples preliminarily tested with a tuberculin skin test and/or BOVIGAM® and 54 negative blood samples collected from three bTB free farms were subjected to IFN-γ assay using the TB-Feron Plus and the BOVIGAM®, respectively. The result shows that the sensitivity, specificity and accuracy were 81.0% (34/42), 100% (54/54), 91.7% (88/96) in TB-Feron Plus kit and 78.6% (33/42), 100% (54/54), 90.6% (87/96) in BOVIGAM® kit, respectively. Moreover, the overall accordance percentage of the two kits was 99.0% (95/96) and there was almost perfect agreement between two assays (Kappa=0.977, P<0.0001). Furthermore, additional studies confirmed that elevated lymphocyte numbers in blood did not interfere with the results of the TB-Feron Plus kit. And, delayed time from sampling to culture decreased the optical density (OD) value. Therefore, we concluded that the TB-Feron Plus kit was not inferior to BOVIGAM® in performance. High lymphocyte numbers in blood did not impact on TB-Feron Plus results, while delayed time before culture interfered with OD value.

Performance of Homologous and Heterologous Prime-Boost Immunization Regimens of Recombinant Adenovirus and Modified Vaccinia Virus Ankara Expressing an Ag85B-TB10.4 Fusion Protein against Mycobacterium tuberculosis

  • Kou, Yiming;Wan, Mingming;Shi, Wei;Liu, Jie;Zhao, Zhilei;Xu, Yongqing;Wei, Wei;Sun, Bo;Gao, Feng;Cai, Linjun;Jiang, Chunlai
    • Journal of Microbiology and Biotechnology
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    • 제28권6호
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    • pp.1022-1029
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    • 2018
  • Tuberculosis (TB) remains a serious health issue around the word. Adenovirus (Ad)-based vaccine and modified vaccinia virus Ankara (MVA)-based vaccine have emerged as two of the most promising immunization candidates over the past few years. However, the performance of the homologous and heterologous prime-boost immunization regimens of these two viral vector-based vaccines remains unclear. In the present study, we constructed recombinant Ad and MVA expressing an Ag85B-TB10.4 fusion protein (AdH4 and MVAH4) and evaluated the impact of their different immunization regimens on the humoral and cellular immune responses. We found that the viral vector-based vaccines could generate significantly higher levels of antigen-specific antibodies, $IFN-{\gamma}$-producing splenocytes, $CD69^+CD8^+$ T cells, and $IFN-{\gamma}$ secretion when compared with bacillus Calmette-$Gu{\acute{e}}rin$ (BCG) in a mouse model. AdH4-containing immunization regimens (AdH4-AdH4, AdH4-MVAH4, and MVAH4-AdH4) induced significantly stronger antibody responses, much more $IFN-{\gamma}$-producing splenocytes and $CD69^+CD8^+$ T cells, and higher levels of $IFN-{\gamma}$ secretion when compared with the MVAH4-MVAH4 immunization regimen. The number of $IFN-{\gamma}$-producing splenocytes sensitive to $CD8^+$ T-cell restricted peptides of Ag85B (9-1p and 9-2p) and Th1-related cytokines ($IFN-{\gamma}$ and $TNF-{\alpha}$) in the AdH4-MVAH4 heterologous prime-boost regimen immunization group was significantly higher than that in the other viral vector-based vaccine- and BCG-immunized groups, respectively. These results indicate that an immunization regimen involving AdH4 may have a higher capacity to induce humoral and cellular immune responses against TB in mice than that by regimens containing BCG or MVAH4 alone, and the AdH4-MVAH4 prime-boost regimen may generate an ideal protective effect.

백서에서 식품 복합물 TB001의 단회 경구투여 독성 시험 연구 (Single Oral Dose Toxicity of TB001 in Rats)

  • 차윤엽;선승호;박원형;박동식;김재현;김희연;임상현;김경희
    • 한방재활의학과학회지
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    • 제21권4호
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    • pp.41-47
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    • 2011
  • Objectives: This study was performed to investigate single oral dose toxicity of TB001, the extract mixture of Purple loosestrife and Aceriphyllum rossii. Methods: The mortality, general symptom, change of weight: and necropcy findings was investigated for 14 days after a dose(2000 mg/kg B.W.) of TB001 was given, using SD rats of both male and female according to "The guideline of toxicity test for medicine and others". Results: The death of rats and abnormal finding was not observed. There was no the significant difference of weight between control group and TB001 group. Conclusions: The abnormalities at the necropsy finding of all survived rats was not detected. The study suggested that there is no toxicity in single dose(2000 mg/kg B.W.) of TB001.

$Tb^{3+}$$Eu^{3+}$로 활성화된 $Al_3GdB_4O_{12}$ 형광체의 발광특성 (Photoluminance Properties of $Al_3GdB_4O_{12}$ Phosphors Activated by $Tb^{3+}$and $Eu^{3+}$)

  • 김기운;김성우;이임렬
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
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    • pp.594-597
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    • 1999
  • The new green and red phosphors for PDP application activated by T $b^{3+}$ and E $u^{3+}$ were synthesized, and their photoluminance properties were investigated. It was found that the brightness of $Al_3$Gd $B_4$ $O_{12}$ :T $b^{3+}$ green phosphor under 147nm VUV irradiation was higher than that of commercial Z $n_2$ $SiO_4$:M $n^{2+}$ phosphor. But the emitting intensity of A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ red phosphor was inferior to the commercial (Y,Gd)B $O_3$:E $u^{3+}$. $Al_3$Gd $B_4$ $O_{12}$ Phosphor had a strong excitation band at 160nm associated with the host absorption, and also the photoluminance excitation intensity of $Al_3$Gd $B_4$ $O_{12}$ :T $b^{3+}$ was higher than that of Z $n_2$ $SiO_4$:M $n^{2+}$, but the intensity of $Al_3$Gd $B_4$ $O_{12}$ :E $u^{3+}$ phosphor was smaller than (Y,Gd)B $O_3$:E $u^{3+}$ phosphor In the VUV range. C $e^{3+}$ co-doping in A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ and substitution of $Al^{3+}$ by G $a^{3+}$ A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ phosphor were tried, but they did not improved the optical property .d the optical property .ty .

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타피오카와 겉보리 혼합원료의 당화 및 알코올 발효의 특성 연구 (Saccharification and alcohol fermentation characteristics of a mixture of tapioca and hulled barley)

  • 김선혜;오종수;강성태
    • 한국식품과학회지
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    • 제51권1호
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    • pp.18-23
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    • 2019
  • 알코올 발효에 이용되는 타피오카와 겉보리 혼합원료의 효소당화액을 제조하여 알코올 발효 특성을 조사하였다. 타피오카와 겉보리 혼합원료를 내열성 액화효소인 Spezyme Fred를 0.04% 사용하여 액화하고 글루코아밀레이스(G), 단백질가수분해효소(P), 베타글루칸 가수분해효소(B)를 혼합한 당화효소제(GPB)를 사용하여 당화하였다. 타피오카와 겉보리 혼합원료(7:3, w/w)를 $50^{\circ}C$에서 150분간 당화하였을 때 당화액의 포도당 함량은 11.9%였고 점도는 26 cp로 나타났다. 베타글루칸 가수분해효소(B)의 첨가는 당화액의 포도당 수율의 증가와 점성의 저하에 도움을 주었다. 타피오카와 겉보리의 혼합비율을 7:3(w/w)으로 하였을 때 다른 비율의 당화액에 비하여 점도가 낮으며 포도당 함량이 높게 나타났다. 타피오카와 겉보리 혼합원료에 300%의 가수량으로 확립된 조건에서 당화하고 $30^{\circ}C$에서 72시간 알코올 발효를 수행한 결과 타피오카와 겉보리 혼합원료를 이용한 알코올 발효에 적합한 발효액의 알코올 및 포도당 함량은 각각 9.0과 0.02%였고, pH와 산도는 각각 pH 4.3과 0.3%이었다.

Overexpression of sprA and sprB Genes is Tightly Regulated in Streptomyces griseus

  • KIM , YOON-HEE;CHOI, SI-SUN;KANG, DAE-KYUNG;KANG, SANG-SOON;JEONG, BYEONG-CHUL;HONG, SOON-KWANG
    • Journal of Microbiology and Biotechnology
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    • 제14권6호
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    • pp.1350-1355
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    • 2004
  • The sprA and sprB genes, encoding the chymotrypsin-like proteases Streptomyces griseus protease A (SGPA) and Streptomyces griseus protease B (SGPB), and the sprT gene that encodes Streptomyces griseus trypsin (SGT) were cloned from S. griseus and were overexpressed in various strains of S. griseus. When the sprT gene was introduced into S. griseus, trypsin activity increased 2-fold in the A-factor deficient mutant strain, S. griseus HH1, and increased 4-fold in the wild strain, S. grise us IFO 13350. However, there was no detectable increase of chymotrypsin activity in the transformants of S. griseus with either sprA or sprB, in contrast to the results obtained from S. lividans as a heterologous host. To solve the negative gene dosage effects in S. griseus, either the sprA or the sprB genes with their own ribosome binding sites were linked to the downstream of the entire sprT gene, and the coexpression efficiency was examined in S. lividans and S. griseus. The transformants of S. lividans with either pWHM3-TA (sprT+sprA) or pWHM3­TB (sprT+sprB) showed 3-fold increase of trypsin activity over that of the control, however, only the transformant of pWHM3-TB demonstrated 7-fold increase in chymotrypsin activity, indicating that the pWHM3-TB has a successful construction for the overexpression of chymotrypsin in Streptomyces. When the coexpression vectors were introduced into S. griseus IFO 13350, the trypsin level sharply increased by more than 4-fold, however, the chymotrypsin level did not increase. These results strongly suggest that the overexpression of the sprA and sprB genes is tightly regulated in S. griseus.

불순물을 첨가한 $MgB_4O_7$ 열형광체의 물리적 특성에 관한 연구 (A Study on the Physical Properties of Impurity Doped $MgB_4O_7$ Porsphors)

  • 김영국;손인호;채건식;이수대;설정식;노경석;송재흥;이상윤;도시홍
    • 한국재료학회지
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    • 제8권2호
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    • pp.173-178
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    • 1998
  • $MgB_4O_7$ 열형광체의 활성체는 란탄계 금속인 Tb, Tm, Dy, La, Ho 및 Nd를 첨가하여 $580^{\circ}C$의 Ar 분위기에서 2시간동안 소결하여 제작하였다. 활성화에너지와 glow 곡선의 주 Peak의 세기는 peak shape법과 초기상승법의 두방법에 의해 결정했으며, 최적활성에너지는 $0.76\pm0.02eV$(Tm 첨가시), $0.94\pm0.03eV$(Tm 첨가시) 및 $0.72\pm0.02eV$(Dy 첨가시)였다. 이들 열형광체들은 저 에너지 X-선에 대해 매우 높은 감도를 나타냈으므로 방사선 센서 소자로 개발하기 위한 기초자료가 될 것으로 생각된다.

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Mycobacterium tuberculosis Derived Epitope Peptide Specific CD8+T Cell Responses in Tuberculous Pleurisy

  • ;;;;;조상래;조성애
    • 대한의생명과학회지
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    • 제13권4호
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    • pp.325-332
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    • 2007
  • Cell-mediated immune response (CMI) is a major immune protective mechanism against tuberculosis (TB) infection. Among several components involved in CMI, recent studies suggest that CD8+ T cells are important in controlling TB infection. In our previous report, we defined four Mycobacterium tuberculosis (MTB) derived epiotpe peptides specific for HLA-A*0201-restricted CD8+ T cells. These four peptides are $PstAl_{75-83}$, $ThyA_{30-38}$, $RpoB_{127-135}$ and $85B_{15-23}$. In this study, these epitope peptides specific CD8+ T cell responses in tuberculous pleurisy were investigated using ex vivo $IFN-\gamma$ elispot assay and intracellular $IFN-\gamma$ staining method. As a result, we observed these epitope peptide specific CD8+ T cell responses are induced in all three patients with tuberculous pleurisy suggesting that CD8+ T cells are involved in protective immune mechanism against MTB infection in tuberculous pleurisy. However, the CMI to mitogens and MTB antigens from pleural fluids of patients with tuberculous pleurisy does not seem to correlate with that from peripheral blood, although the sample size is too small to make any conclusion. In sum, the MHC I restricted CD8+ T cell responses seem to be induced efficiently in the pleural fluids, at the site of TB infection, in which the CMI is actively induced. In addition, these experiments suggest that MHC I restricted CD8+ T cell mediated immune responses are also involved in protective mechanism against MTB infection in extra-pulmonary TB.

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