• Title/Summary/Keyword: Modification of $S_e$

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Dietary manipulation: a sustainable way to mitigate methane emissions from ruminants

  • Haque, Md Najmul
    • Journal of Animal Science and Technology
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    • v.60 no.6
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    • pp.15.1-15.10
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    • 2018
  • Methane emission from the enteric fermentation of ruminant livestock is a main source of greenhouse gas (GHG) emission and a major concern for global warming. Methane emission is also associated with dietary energy lose; hence, reduce feed efficiency. Due to the negative environmental impacts, methane mitigation has come forward in last few decades. To date numerous efforts were made in order to reduce methane emission from ruminants. No table mitigation approaches are rumen manipulation, alteration of rumen fermentation, modification of rumen microbial biodiversity by different means and rarely by animal manipulations. However, a comprehensive exploration for a sustainable methane mitigation approach is still lacking. Dietary modification is directly linked to changes in the rumen fermentation pattern and types of end products. Studies showed that changing fermentation pattern is one of the most effective ways of methane abatement. Desirable dietary changes provide two fold benefits i.e. improve production and reduce GHG emissions. Therefore, the aim of this review is to discuss biology of methane emission from ruminants and its mitigation through dietary manipulation.

MODIFICATION OF INITIALLY GROWN BN LAYERS BY POST-N$^{+}$ IMPLANTATION

  • Byon, E-S.;Lee, S-H.;Lee, S-R.;Lee, K-H.;Tian, J.;Youn, J-H.;Sung, C.
    • Journal of the Korean institute of surface engineering
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    • v.32 no.3
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    • pp.351-355
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    • 1999
  • BN films with a high content of cubic phase has been deposited by a variety of techniques. It is well known that c-BN films grow with a unique microstructure consisting of $sp^2$ and $sp^{3-}$ bonded layers. Because of existence of the initially grown $sp^{2-}$ /bonded layer, BN films are not adhesive to the substrates. In this study, post-N$^{+ }$ / implantation was applied to improve the adhesion of the films. A Monte Carlo program TAMIX was used to simulate this modification process. The simulation showed nitrogen concentration profile at $1200\AA$ in depth in case of 50keV -implantation energy. FTIR spectra of the $N^{+}$ implanted specimens demonstrated a strong change of absorption band at 1380 cm$^{ -1 }$The films were also investigated by HRTEM. From these results, it is concluded that the post ion implantation could be an effective technique which improves the adhesion between BN film and substrate.

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A Study on a Direction of Modification of the Trade and International Business Curriculum for Global Trade Expert (글로벌무역인력 양성을 위한 합리적인 무역학 교과과정 개편방향에 관한 연구)

  • Park, Kwang-So;Yu, Kwang-Hyun
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.37
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    • pp.329-360
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    • 2008
  • In Korea, the major of international trade and business introduced in the 1960s to supply trade expert to trading companies, and the heyday of the trade major was in the 1980s. However the trade major fell into decay from the middle of 1990s. The purpose of trade education in university is to supply high qualified employees to societies and companies. The problem is that companies have difficuties for recruiting of trade expert, on the other hand university graduates have few job oppertunies. It has some discrepancies between education and field. The object of this paper is to propose a direction of modification of the trade and international business curriculum for global trade expert. We research international trade and business departments' curriculums of GTEP universities. GTEP stands for global trade expert incubating program started from 2006 which have charge of MOCIE and KITA. First, in the title of department, a lot of former researchers have taken up the position to return "Trade" or "International Trade". We think more important fact is not the title of department but the curriculum, so we insist on a harmony between the department title and curriculums. The focus of modification of curriculum is to educate global trade expert, so we need to know about global business environment and companies' needs also. Second, We propose the directions for modification of curriculum are "convergence" and "specialty". Trade major is a mixed study in nature and trade major try to treat lots of subjects such as trade, business adminstration, economics, international law, international commerce, logistics and marketing etc to catch up changing global business circumstanses and companies' needs. So convergence of adjacent field is very important in study and training. Specialty means selection and concentration strategy for global trade expert. It is difficult to learn every knowledge and skills for employer's needs in 4 years and 140 credits. A students who has studied basic subject in trade, management, economics can choose 1 or 2 specailty subject such as trade and e-commerce, global marketing, logistics and transportation, commerce and policy, servive trade, foreign language and cross culture etc. In concusion, the concept of convergence and specialty is not separation but harmony each other, so we propose to promote two concept together for modification of the trade and international business curriculum for training of global trade expert.

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Structure and Biological Function of Plant CRL4, and Its Involvement in Plant Cellular Events (식물 CRL4 복합체의 구조, 기능 및 식물 세포 내 다양한 이벤트와의 연계성)

  • Lee, Jae-Hoon
    • Journal of Life Science
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    • v.26 no.3
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    • pp.364-375
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    • 2016
  • Post-translational modification is an efficient process to rapidly transduce external stimulus into cellular response. Ubiquitination is a typical post-translational modification which is a highly conserved process in eukaryotes. UPS (Ubiquitin/Proteasome System) mediated by the ubiquitination is to target diverse cellular proteins for degradation. Among E3 ubiquitin ligases that function as the key determinant for substrate recognition, CRL (cullin–RING E3 ubiquitin ligase) is the largest family and forms the complex composed of cullin, RBX1, adaptor and substrate receptor. Although CRL1, also known as SCF complex, has been widely researched for its biological role, the functional studies of CRL4 have been relatively elusive. In Arabidopsis, there are 119 substrate receptors named DCAF (DDB1 CUL4 Associated Factor) proteins for CRL4 and a fraction of DCAF proteins have been identified for their potential functions so far. In this paper, current understanding on structure and biological roles of plant CRL4 complexes in a diverse of cellular events is reviewed, especially focusing on CRL4 substrate receptors. Moreover, the regulatory mechanism of CRL4’s activity is also introduced. These studies will be helpful to further understand the signal transduction pathways in which such CRL4 complexes are involved and give a clue to establish the action network of entire CRL4 complexes in plants.

Enhanced Security Framework for E-Health Systems using Blockchain

  • Kubendiran, Mohan;Singh, Satyapal;Sangaiah, Arun Kumar
    • Journal of Information Processing Systems
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    • v.15 no.2
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    • pp.239-250
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    • 2019
  • An individual's health data is very sensitive and private. Such data are usually stored on a private or community owned cloud, where access is not restricted to the owners of that cloud. Anyone within the cloud can access this data. This data may not be read only and multiple parties can make to it. Thus, any unauthorized modification of health-related data will lead to incorrect diagnosis and mistreatment. However, we cannot restrict semipublic access to this data. Existing security mechanisms in e-health systems are competent in dealing with the issues associated with these systems but only up to a certain extent. The indigenous technologies need to be complemented with current and future technologies. We have put forward a method to complement such technologies by incorporating the concept of blockchain to ensure the integrity of data as well as its provenance.

Anticarcinogenic Effect and Modification of Cytochrome P450 2E1 by Dietary Garlic Powder in Diethylnitrosamine-Initiated Rat Hepatocarcinogenesis

  • Park, Kyung-Ae;Kweon, Sang-Hui;Choi, Hay-Mie
    • BMB Reports
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    • v.35 no.6
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    • pp.615-622
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    • 2002
  • The purpose of this study was to determine the effects of dietary garlic powder on diethylnitrosamine (DEN)-induced hepatocarcinogenesis and cytochrome P450 (CYP) enzymes in weaning male Sprague-Dawley rats by using the medium-term bioassay system of Ito et al. The rats were fed diets that contained 0, 0.5, 2.0 or 5.0% garlic powder for 8 weeks, beginning the diets with the intraperitoneal (i.p.) injection of DEN. The areas of placental glutathione S-transferase (GST-P) positive foci, an effective marker for DEN-initiated lesions, were significantly decreased in the rats that were fed garlic-powder diets; the numbers were significantly decreased only in the 2.0 and 5.0% garlic-powder diets. The p-nitrophenol hydroxylase (PNPH) activities and protein levels of CYP 2E1 in the hepatic microsomes of the rats that were fed the 2.0 and 5.0% garlic powder diet were much lower than those of the basal-diet groups. Pentoxyresorufin O-dealkylase (PROD) activity and CYP 2B1 protein level were not influenced by the garlic-powder diets and carcinogen treatment. Therefore, the suppression of CYP 2E1 by garlic in the diet might influence the formation of preneoplastic foci during hepatocarcinogenesis in rats that are initiated with DEN.

Modification of Starch using Dextransucrase and Characterization of the Modified Starch. (덱스트란수크라제를 이용한 전분의 변형 및 특성 조사)

  • ;;;;;John E. Robyt
    • Microbiology and Biotechnology Letters
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    • v.26 no.2
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    • pp.143-150
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    • 1998
  • Many enzymes catalyze a primary reaction and/or secondary reaction. Dextransucrase usually synthesize dextran from sucrose as a primary reaction. The secondary reaction of dextransucrase is the transfer of glucose from sucrose to carbohydrate accepters. We have reacted dextransucrase from Leuconostoc mesenteroides B-742CB with sucrose and starches; granule or gelatinized starches, and Small or Potato starches. The yield of modified starch was ranged from 46% to 72%(s.d.<${pm}$5%) of theoretical depends on various reaction conditions. Modified products were more resistant against the hydrolysis of ${alpha}$-amylase, isoamylase, pullulanase and endo-dextranase than those of native starch. Based on the reactions from enzyme hydrolysis and methylation followed by acid hydrolysis modification of granule starch was more efficient than the modification of gelatinized starch. After modification of granule starch with dextransucrase, there produced a soluble modified starch. After modification the starch granules were fractionated to small size. The positions of glucose substitution of the modified products were determined by methylation followed by acid hydrolysis and analyzed by TLC. The products were modified by the addition of glucose to the position of C3, C4 and C6 free hydroxyl group of glucose residues in the starch.

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Significance of Cell Cycle and Checkpoint Cnotrol (세포주기조절에 관한 최근 연구)

  • 최영현;최혜정
    • Journal of Life Science
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    • v.11 no.4
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    • pp.362-370
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    • 2001
  • Regulation of cell proliferation is a complex process involving the regulated expression and /or modification of discrete gene products. which control transition between different stages of the cycle. The purpose of this short review is to provide an overview of somatic cell cycle events and their controls. Cycline have appeared as major positive regulators in this network, because their association to the cyclin-dependent kinases(Cdks) allows the subsequent activation on the Cdk/cyclin complexes and their catalatic activity. In mammalian cells, early to mid G1 progression and late G1 progression leading to S phase entry are directed by D-type cyclins-Cdk4, 6 and cyclin E-Cdk 2 both of which can phosphorylate the retinoblastoma protein (pRB). pRB is a transcriptional repressor which, in its unphosphorylated state, binds to members of the E2F transcription factor family and blocks E2F-dependent transcription of genes controlling the G1 to S phase transition an subsequent DNA synthesis. Cyclin A is produced in late G1 and expressed during S and G2 phae, and expression of B-type cyclins is typically maximal during the G2 to M phase transition and it controls the passage through M phase. They primarily associate with the activate Cdk2, and Cdc2, respectively. On the other hand, the Cdk inhibitors negatively control the activity of C아/cyclin complex by coordinating internal and/or external signals and impending proliferation at several key checkpoints. These current and further findings will provide novel approaches to understanding and treating major diseases.

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The Site-Directed A184S Mutation in the HTH Domain of the Global Regulator IrrE Enhances Deinococcus radiodurans R1 Tolerance to UV Radiation and MMC Shock

  • Zhang, Chen;Zhou, Zhengfu;Zhang, Wei;Chen, Zhen;Song, Yuan;Lu, Wei;Lin, Min;Chen, Ming
    • Journal of Microbiology and Biotechnology
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    • v.25 no.12
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    • pp.2125-2134
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    • 2015
  • IrrE is a highly conserved global regulator in the Deinococcus genus and contributes to survival from high doses of UV radiation, ionizing radiation, and desiccation. Drad-IrrE and Dgob-IrrE from Deinococcus radiodurans and Deinococcus gobiensis I-0 each share 66% sequence identity. However, Dgob-IrrE showed a stronger protection phenotype against UV radiation than Drad-IrrE in the D. radiodurans irrE-deletion mutant (ΔirrE), which may be due to amino acid residues differences around the DNA-binding HTH domain. Site-directed mutagenesis was used to generate a Drad-IrrE A184S single mutant, which has been characterized and compared with the ΔirrE mutant complemented strain with Drad-irrE, designated ΔirrE-E. The effects of the A184S mutation following UV radiation and mitomycin C (MMC) shock were determined. The A184S mutant displayed significantly increased resistance to UV radiation and MMC shock. The corresponding A184 site in Dgob-IrrE was inversely mutated, generating the S131A mutant, which exhibited a loss of resistance against UV radiation, MMC shock, and desiccation. qPCR analysis revealed that critical genes in the DNA repair system, such as recA, pprA, uvrA, and ddrB, were remarkably induced after UV radiation and MMC shock in the ΔirrE-IE and A184S mutants. These data suggested that A184S improves the ability against UV radiation and MMC shock, providing new insights into the modification of IrrE. We speculated that the serine residue may determine the efficiency of DNA binding, leading to the increased expression of IrrE-dependent genes important for protection against DNA damage.

Chemical Modification of Botryosphaeran: Structural Characterization and Anticoagulant Activity of a Water-Soluble Sulfonated ($1{\rightarrow}3$)($1{\rightarrow}6$)-${\beta}$-D-Glucan

  • Brandi, Jamile;Oliveira, Eder C.;Monteiro, Nilson K.;Vasconcelos, Ana Flora D.;Dekker, Robert F.H.;Barbosa, Aneli M.;Silveira, Joana L.M.;Mourao, Paulo A.S.;Silva, Maria De Lourdes Corradi Da
    • Journal of Microbiology and Biotechnology
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    • v.21 no.10
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    • pp.1036-1042
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    • 2011
  • The exopolysaccharide botryosphaeran ($EPS_{GLC}$; a ($1{\rightarrow}3$)($1{\rightarrow}6$)-${\beta}$-D-glucan from Botryosphaeria rhodina MAMB-05) was sulfonated to produce a water-soluble fraction ($EPS_{GLC}$-S) using pyridine and chlorosulfonic acid in formamid. This procedure was then repeated twice to produce another fraction ($EPS_{GLC}$-RS) with a higher degree of substitution (DS, 1.64). The purity of each botryosphaeran sample (unsulfonated and sulfonated) was assessed by gel filtration chromatography (Sepharose CL-4B), where each polysaccharide was eluted as a single symmetrical peak. The structures of the sulfonated and re-sulfonated botryosphaerans were investigated using ultraviolet-visible (UV-Vis), Fourier-transform infrared (FT-IR), and $^{13}C$ nuclear magnetic resonance ($^{13}C$ NMR) spectroscopies. $EPS_{GLC}$ and $EPS_{GLC}$-RS were also assayed for anticoagulation activity, and $EPS_{GLC}$-RS was identified as an anticoagulant.