• Title/Summary/Keyword: NBS

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Functional Amino Acid Residues of Recombinant Tobacco Acetolactate Synthase

  • Chong, Chom-Kyu;Chang, Soo-Ik;Choi, Jung-Do
    • BMB Reports
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    • v.31 no.3
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    • pp.258-263
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    • 1998
  • Acetolactate synthase (ALS) is the common enzyme in the biosynthetic pathways leading to leucine, valine, and isoleucine. Tobacco ALS was expressed in E. coli and purified to homogeneity. The recombinant tobacco ALS was inactivated by thiol-specific reagents, N-ethylmaleimide (NEM) and 5,5'-dithio-bis-(2-nitrobenzoic acid) (DTNB). Inactivation of the ALS by NEM followed pseudo-first order kinetics and was first order with respect to the modifier. The substrate pyruvate protected the enzyme against the inactivation by NEM and DTNB. Extrapolation to complete inactivation of the enzyme by DTNB showed modification of approximately 2 out of 4 total cysteinyl residues (or 2 cysteinyl and 1 cysteinyl residues), with approximately 1 residue protected by pyruvate. The tobacco ALS was also inactivated by the tryptophanspecific reagent, N-bromosuccinimide (NBS), and was similarly protected by pyruvate. The kinetics of the inactivation was first-order with respect to NBS. The present data suggest that cysteinyl and tryptophanyl residues play a key role in the catalytic function of the enzyme.

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Flexural bond strength behaviour in OPC concrete of NBS beam for various corrosion levels

  • Shetty, Akshatha;Venkataramanaa, Katta;Babu Narayan, K.S.
    • Structural Engineering and Mechanics
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    • v.49 no.1
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    • pp.81-93
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    • 2014
  • Corrosion is one of the primary reasons why structures have limited durability. The present investigation is carried out to study the behavior of RC (Reinforced Concrete) structural members subjected to corrosion. Experimental investigations were carried out on National Bureau of Standard (NBS), RC beam specimens made of Ordinary Portland Cement (OPC) concrete. Load versus deflection behaviour was studied for different levels of corrosion i.e., 2.5%, 5%, 7.5% and 10%. It is observed that for every percentage increase in corrosion level, there is about 1.6% decrease in load carrying capacity. Also as the amount of corrosion increases there is a reduction in bond stress.

Effect of Hydrogen in the Gate Insulator on the Bottom Gate Oxide TFT

  • KoPark, Sang-Hee;Ryu, Min-Ki;Yang, Shin-Hyuk;Yoon, Sung-Min;Hwang, Chi-Sun
    • Journal of Information Display
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    • v.11 no.3
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    • pp.113-118
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    • 2010
  • The effect of hydrogen in the alumina gate insulator on the bottom gate oxide thin film transistor (TFT) with an InGaZnO film as the active layer was investigated. TFT with more H-containing alumina films (TFT A) fabricated via atomic layer deposition using a water precursor showed higher stability under positive and negative bias stresses than that with less H-containing alumina deposited using ozone (TFT B). While TFT A was affected by the pre-vacuum annealing of GI, which resulted in $V_{th}$ instability under NBS, TFT B did not show a difference after the pre-vacuum annealing of GI. All the TFTs showed negative-bias-enhanced photo instability.

A study on the electromagnetic field distributions in a W-TEM cell having wire array as an inner conductor (와이어 어레이 형태의 내부 도체를 갖는 W-TEM cell의 전자계 분포 특성에 관한 연구)

  • 김명훈;이중근
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.6
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    • pp.1576-1586
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    • 1996
  • The subject of this paper is the analysis of a Wire-TEM cell(W-TEM cell) which has an inner wire array rather than a metallic septum;its basic structure is similiar to a NBS TEM cell. To verify improved performances of this W-TEM cell as a standard EM field generator, well-known quasi-static approximations are employed and their resultant ingegral equations are numerically analyzed by moment method. Although the electric field strength of a W-TEM cell is 1.4 dB lower than tht of a NBS TEM cell, the uniformity of EM field patterns in a W-TEM cell is improved. It is also shown that the EM field distortions resulting from loading by the conditing objects under test(loading effects), are decreased considerably. This paper also deals with the investigations about relationship between the EM field distributions and the number of wire composing the inner conductor. Finally, the experimental analysis is performed on the practical model which is built on the basis of the design variables brought out by the theoretical andnumerical analysis.

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HS-1200 Overcomes the Resistance Conferred by Bcl-2 in Human Leukemic U937 Cells

  • Park, Jun-Young;Moon, Jeong-Bon;Kim, In-Ryoung;Kim, Gyoo-Cheon;Park, Bong-Soo;Kwak, Hyun-Ho
    • International Journal of Oral Biology
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    • v.37 no.3
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    • pp.91-102
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    • 2012
  • Bcl-2 protects tumor cells from the apoptotic effects of various anti-neoplastic agents. Increased expression of Bcl-2 has been associated with a poor response to chemotherapy in various malignancies, including leukemia. Hence, bypassing the resistance conferred by anti-apoptotic factors such as Bcl-2 represents an attractive therapeutic strategy against cancer cells, including leukemic cells. This study was undertaken to examine whether the anticancer drug, cisplatin and the synthetic chenodeoxycholic acid (CDCA) derivative, HS-1200 show anti-tumor activity in U937 and U937/Bcl-2 cells. Viability assays revealed that HS-1200 overcomes the resistance conferred by Bcl-2 in human leukemic U937 cells. Various apoptosis assessment assays further demonstrated that HS-1200 overcomes the resistance conferred by Bcl-2 in human leukemic U937 cells by inducing apoptosis. In addition HS-1200, but not cisplatin, overcomes the anti-apoptotic effects of Bcl-2 in Bcl-2 over-expressing human leukemic cells (U937/Bcl-2 cells). Notably, we observed that the HS-1200-induced formation of mature promyelocytic leukemia (PML) nuclear bodies (NBs) correlates with a suppression of the anti-apoptotic effects of Bcl-2 in human leukemic cells over-expressing this protein (U937/Bcl-2 cells). Furthermore, HS-1200 was found to induce the association between PML and SUMO-1, Daxx, Sp100, p53 or CBP in the aggregated PML-NBs of U937/Bcl-2 cells. Thus, PML protein and the formation of mature PML-NBs could be considered as therapeutic targets that may help to bypass the resistance to apoptosis conferred by Bcl-2. Elucidating the exact mechanism by which PML regulates Bcl-2 will require further work.

Reproduction-Nutrition Relationship in Dairy Buffaloes. I. Effect of Intake of Protein, Energy and Blood Metabolites Levels

  • Qureshi, Muhammad Subhan;Habib, Ghulam;Samad, Hafiz Abdus;Siddiqui, Muhammad Mohsin;Ahmad, Nazir;Syed, Mirajuddin
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.3
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    • pp.330-339
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    • 2002
  • Fifty one Nili-Ravi dairy buffaloes in their last two months of gestation were selected. After parturition, rectal examination of reproductive organs was carried out until the occurrence of the first oestrus (PEI). Milk samples were analyzed for milk progesterone levels (MPL). Ovulation (POI) was confirmed by rectal palpation and MPL. Feed and blood samples were collected fortnightly and analyzed. Body condition score (BCS) was recorded on a scale of 0 to 5. Crude protein (CP) intake varied among different seasons and correlated positively with serum urea levels, POI (p<0.01) and PEI (p<0.05). Excess CPI was lower in the group showing oestrus as compared to those remaining as anoestrus (p<0.05). The dietary ratio of crude protein - metabolizable energy (CP:ME) in the oestrus animals was narrow and constant, while the anoestrus animals had a widely fluctuating one. In normal breeding season (NBS) calvers, mean serum urea level (SUL) was lower than the low breeding season (LBS) calvers. SUL was positively correlated with PEI and POI (p<0.01). Up to six months postpartum, SUL were constantly higher in anoestrus than oestrus buffaloes. Mean metabolizable energy (ME) intake was lower in the NBS calvers than the LBS calvers (p<0.01). BCS and postpartum ovulation interval were correlated with ME intake (p<0.01). Prepartum ME intake was higher in oestrous as compared to anoestrous animals (p<0.05). Higher and lower ME intakes were associated with anoestrus, while a moderate energy intake was associated with a PEI of less than 75 days. Buffaloes with poor BCS belonged to the LBS calving group and most of the NBS calving buffaloes had good BCS. BCS was negatively correlated with PEI (p<0.01) and was higher in oestrous buffaloes than anestrus. It was concluded that excess intake of crude protein, associated with higher serum urea levels and low energy intake, associated with poor body condition, are the key factors for low reproductive efficiency. It may be corrected by adopting a proper feeding strategy.

Interactions between Hyaluronic Acid, Lysozyme, Peroxidase, and Glucose Oxidase in Enzymatic Activities at Low pH

  • Kim, Bum-Soo;Kim, Yoon-Young;Chang, Ji-Youn;Kho, Hong-Seop
    • Journal of Oral Medicine and Pain
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    • v.39 no.4
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    • pp.127-132
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    • 2014
  • Purpose: Many substances in saliva or oral health care products interact with each other. The aim of this study was to investigate interactions between hyaluronic acid (HA), lysozyme, peroxidase, and glucose oxidase (GO) in enzymatic activities at low pH levels. Methods: HA (0.5 mg/mL), hen egg-white lysozyme (HEWL, $30{\mu}g/mL$), bovine lactoperoxidase (bLPO, $25{\mu}g/mL$), and GO ($50{\mu}g/mL$) were used. The influences of HA, bLPO, and GO on HEWL activity were determined by measuring the turbidity of a Micrococcus lysodeikticus suspension. The influences of HA and HEWL on bLPO activity were determined by the NbsSCN assay, measuring the rate of oxidation of 5-thio-2-nitrobenzoic acid (Nbs) to 5,5'-dithiobis(2-nitrobenzoic acid) $(Nbs)_2$. The influences of HA and HEWL on GO activity were determined by measuring oxidized o-dianisidine production. All experiments were performed at pH 4, 5, and 6. Results: HA and GO did not affect the enzymatic activity of HEWL at pH 4, 5, and 6. bLPO enhanced the enzymatic activity of HEWL at pH 5 (p<0.05) and pH 6 (p<0.05) significantly. The enzymatic activity of bLPO was not affected by HA and HEWL at pH 4, 5, and 6. HA and HEWL did not affect the enzymatic activity of the GO at pH 4, 5, and 6. Conclusions: Peroxidase enhances lysozyme activity at low pH, otherwise there were no significant interactions in enzymatic activities between HA, lysozyme, peroxidase, and GO at low pH levels.

Change of Wood Color of Radiata Pine (Pinus radiata D.Don) by Press Temperature and Time (라디에타 소나무재의 압밀화 온도와 시간에 따른 색상의 변화)

  • Hwang, Sung-Wook;Lee, Won-Hee
    • Journal of the Korean Wood Science and Technology
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    • v.39 no.3
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    • pp.238-243
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    • 2011
  • This study was estimated the change of color of compressed wood by compression temperature and time. Wood color was measured using a colorimeter and evaluated by the NBS (National Bureau of Standards) unit. As a result, the whiteness decreased with increasing compression temperature. In contrast, redness and yellowness was increased with increasing compression temperature. All of the color difference showed the 'Very Much' by NBS unit. The whiteness decreased with increasing compression time. The redness and yellowness were insignificant effect on compression temperature. In other words, the effect of compression temperature was much greater than compression time in the change of wood color.

On NeMRI-Based Multicasting for Network Mobility (네트워크 이동성을 고려한 NeMRI 기반의 멀티캐스트 라우팅 프로토콜)

  • Kim, Moon-Seong;Park, Jeong-Hoon;Choo, Hyun-Seung
    • Journal of Internet Computing and Services
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    • v.9 no.2
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    • pp.35-42
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    • 2008
  • Mobile IP is a solution to support mobile nodes, however, it does not handle NEtwork MObility (NEMO). The NEMO Basic Support (NBS) protocol ensures session continuity for all the nodes in the mobile network. Since the protocol is based on Mobile IP, it inherits the same fundamental problem such as tunnel convergence, when supporting the multicast for NEMO. In this paper, we propose the multicast route optimization scheme for NEMO environment. We assume that the Mobile Router (MR) has a multicast function and the Nested Mobile Router Information (NeMRI) table. The NeMRI is used to record o list of the CoAs of all the MRs located below it. And it covers whether MRs desire multicast services. Any Route Optimization (RO) scheme can be employed here for pinball routing. Therefore, we achieve optimal routes for multicasting based on the given architecture. We also propose cost analytic models to evaluate the performance of our scheme. We observe significantly better multicast cost in NEMO compared with other techniques such as Bi-directional Tunneling, Remote Subscription, and Mobile Multicast based on the NBS protocol.

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