• Title/Summary/Keyword: the unit of life science

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Coexpression of Alginate Lyase with Hyperthermophilic Archaea Chaperonin in E. coli (대장균에서 초고온성 샤페로닌과 alginate lyase의 공발현)

  • Kim, Se Won;Kim, Gun-Do;Nam, Soo-Wan
    • Journal of Life Science
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    • v.25 no.2
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    • pp.130-135
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    • 2015
  • When the alginate lyase gene (aly) from Pseudoalteromonas elyakovii IAM 14594 was expressed in E. coli, most of the gene product expressed was produced as aggregated insoluble particles known as inclusion bodies. In order to produce with an elevated level of a soluble and active form of alginate lyase in E. coli, the hyperthermophilic chaperonins (ApCpnA and ApCpnB) from archaeon Aeropyrum pernix K1 were employed as the coexpression partners. At $25^{\circ}C$ culture temperature, the level of alginate lyase activity was increased from 10.1 unit/g-soluble protein in aly single expression to 83.1 unit/g-soluble protein by coexpressing with ApCpnA and to 100.3 unit/g-soluble protein by coexpressing with ApCpnB. This results indicate that the coexpression of aly with ApCpnA and ApCpnB revealed a marked enhancement, about 8~10 fold, in the production of alginate lyase as a soluble and active form. Based on the results of various examinations on the expression variables, the optimal conditions for the maximal production of alginate lyase were determined as 1.0 mM IPTG for the inducer concentration, $25^{\circ}C$ for the culture temperature after IPTG induction, and ApCpnB for the coexpression partner. The coexpression set in the present report may be useful in the industrial production of functionally or medically important recombinant proteins in E. coli.

New Bipolar Green Host Materials Containing Benzimidazole-Carbazole Moiety in Phosphorescent OLEDs

  • Park, Jung-Hwan;Kim, Eun-Kyung;El-Deeb, Ibrahim M.;Jung, Su-Jin;Choi, Dae-Hyuk;Kim, Dong-Ha;Yoo, Kyung-Ho;Kwon, Jang-Hyuk;Lee, So-Ha
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.841-846
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    • 2011
  • New green host materials, 9-phenyl-3-(4-(1-phenyl-1H-benzo[d] imidazol-2-yl)phenyl)-9H-carbazole (3a) and 9-(naphthyl-2-yl)-3-(4-(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl)-9H-carbazole (3b), have been designed and synthesized by attaching the electron transporting benzimidazole moiety to the hole transporting carbazole unit. These compounds have similar HOMO, LUMO levels and band-gap characteristics compared with CBP (4,4'-di(N-carbazolyl)biphenyl). The fabricated green phosphorescent OLED with this 3a host shows much better device performances compared to CBP-based one. The current and power efficiency is enhanced at least by 60 percent at a given constant luminance of 1000 cd/$m^2$.

Analysis of academic achievements on above-level testing of newly entering students in science specialized high schools (상급 학년 수준 시험을 활용한 과학고 신입생들의 학업성취도 특성 연구)

  • Ahn, Tae Hwan;Park, Kyung Hee
    • Journal of Gifted/Talented Education
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    • v.25 no.1
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    • pp.119-138
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    • 2015
  • This study analyzed the academic achievements on above-level testing of mathematics, physics, chemistry, and English in newly entering students of science specialized high schools. It can be expected that newly students of science high specialized schools have reached ceiling level in the middle school mathematics and science academic scores. Above-level testing(or off-level testing) is a test tool used to evaluate student's ability which are above-grade level. In this study, above-level testing tools were used to develop the same type examination paper of the 2013 Korean College Scholastic Ability Test(CSAT) in mathematics, physics, chemistry, and English. The conclusions of this study were as follow: First, the academic achievement level of science specialized high school freshmen were higher the average level of general high school senior because that over 50% of them are within the 5 grade of CSAT in mathematics, physics, and chemistry. In English, 19.3% science specialized high school freshmen have reached within the 5 grade of CSAT. Second, as a result of examining characteristics of academic achievement with respect to units of subjects, in mathematics, it was showed that the academic achievement of 'continuity and limit of a function' unit was higher, 'statistics' unit was lower. In physics, the academic achievement of 'Electricity and Magnetism' unit was higher, 'Waves and particles' unit was lower. In chemistry, the academic achievement of 'compounds in life' unit was higher, 'Air' unit was lower. In English, the academic achievement of 'practical sentence' of reading area was higher, 'Sentence' of writing area was lower. In conclusion, above-level testing provided a good strategy for identifying and determining appropriate programming interventions for gifted students who are two or more grade levels above their age-mates in achievements, aptitude, or ability.

Concept Analysis of Relocation Stress - Focusing on Patients Transferred from Intensive Care Unit to General Ward - (전실 스트레스[relocation stress]의 개념분석 - 중환자실에서 일반 병실로 전실하는 환자를 중심으로 -)

  • Son, Youn-Jung;Hong, Sung-Kyung;Jun, Eun-Young
    • Journal of Korean Academy of Nursing
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    • v.38 no.3
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    • pp.353-362
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    • 2008
  • Purpose: This study was conducted to analyze and clarify the meaning of the concept for relocation stress -focusing on patients transferred from an intensive care unit to a general ward. Methods: This study used Walker and Avant's process of concept analysis. Results: Relocation stress can be defined by these attributes as follows: 1) involuntary decision about relocation, 2) moving from a familiar and safe environment to an unfamiliar one, 3) broken relationship of safety and familiarity, 4) physiological and psychosocial change after relocation. The antecedents of relocation stress consisted of these facts: 1) preparation degrees of transfer from the intensive care unit to a general ward, 2) pertinence of the information related to the transfer process, 3) change of major caregivers, 4) change in numbers of monitoring devices, 5) change in the level of self-care. There are consequences occurring as a result of relocation stress: 1) decrease in patients' quality of life, 2) decrease in coping capacity, 3) loss of control. Conclusion: Relocation stress is a core concept in intensive nursing care. Using this concept will contribute to continuity of intensive nursing care.

The Development of Experiential Places and a Task-based Experiential Learning Program in 3~4th Grade Curriculum of 2009 (2009개정 3~4학년군 과학교육과정과 연계한 체험학습 장소 및 과제형 체험학습 프로그램 개발)

  • Kwon, HyoekJae;Kang, Hountae;Kwon, Nanjoo
    • Journal of Korean Elementary Science Education
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    • v.36 no.3
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    • pp.273-285
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    • 2017
  • The purpose of this study is to develop a program that enables students to participate in various experiential learning places in order to provide various experiences to students for solve the problem of prejudice to specific places such as science museum, zoo and botanical garden. For this purpose, the surveys were conducted about experiential places and awareness of experiential learning. 88 elementary school teachers participated in the survey. As a result, they were positive about the use of experiential learning in elementary science instruction, but there were responses that a lot of preparations for the progress and efforts were needed. Therefore, if instructional materials and teaching materials for experiential learning are given, it is confirmed that the intention of using is increased. And the results were analyzed and the experiential sites were categorized into 12 types. We could present basic data that can diversify not only the science museum but also science related experiential places. We developed a learning program related to 'The Liquid and Gas' unit of the third grade, And 'Life unit of Plant' unit of the third $4^{th}$ grade. Through this study, we intend to help science experiential learning to be activated and student - centered experiential learning to be realized.

Blood transcriptome resources of chinstrap (Pygoscelis antarcticus) and gentoo (Pygoscelis papua) penguins from the South Shetland Islands, Antarctica

  • Kim, Bo-Mi;Jeong, Jihye;Jo, Euna;Ahn, Do-Hwan;Kim, Jeong-Hoon;Rhee, Jae-Sung;Park, Hyun
    • Genomics & Informatics
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    • v.17 no.1
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    • pp.5.1-5.9
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    • 2019
  • The chinstrap (Pygoscelis antarcticus) and gentoo (P. papua) penguins are distributed throughout Antarctica and the sub-Antarctic islands. In this study, high-quality de novo assemblies of blood transcriptomes from these penguins were generated using the Illumina MiSeq platform. A total of 22.2 and 21.8 raw reads were obtained from chinstrap and gentoo penguins, respectively. These reads were assembled using the Oases assembly platform and resulted in 26,036 and 21,854 contigs with N50 values of 929 and 933 base pairs, respectively. Functional gene annotations through pathway analyses of the Gene Ontology, EuKaryotic Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were performed for each blood transcriptome, resulting in a similar compositional order between the two transcriptomes. Ortholog comparisons with previously published transcriptomes from the $Ad{\acute{e}}lie$ (P. adeliae) and emperor (Aptenodytes forsteri) penguins revealed that a high proportion of the four penguins' transcriptomes had significant sequence homology. Because blood and tissues of penguins have been used to monitor pollution in Antarctica, immune parameters in blood could be important indicators for understanding the health status of penguins and other Antarctic animals. In the blood transcriptomes, KEGG analyses detected many essential genes involved in the major innate immunity pathways, which are key metabolic pathways for maintaining homeostasis against exogenous infections or toxins. Blood transcriptome studies such as this may be useful for checking the immune and health status of penguins without sacrifice.

Neurodegenerative Dementias: A Brief Review

  • Sin, Mo-Kyung;Khemani, Pravin
    • Journal of Korean Biological Nursing Science
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    • v.22 no.3
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    • pp.172-175
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    • 2020
  • Purpose: The purpose of this paper is to provide nurses with a concise review on neurodegenrative dementias. This review includes pathophysiology, clinical course, and tips on management of dementias from Alzheimer's disease (AD), Parkinson disease (PD) and lewy body dementia (LBD). Considering increasing numbers of dementia cases among older adults, nurses who are cognizant about dementia care are instrumental in maximizing daily activities and quality of life of patients with cognitive impairment and dementia.

Characterization of AprE176, a Fibrinolytic Enzyme from Bacillus subtilis HK176

  • Jeong, Seon-Ju;Heo, Kyeong;Park, Ji Yeong;Lee, Kang Wook;Park, Jae-Yong;Joo, Sang Hoon;Kim, Jeong Hwan
    • Journal of Microbiology and Biotechnology
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    • v.25 no.1
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    • pp.89-97
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    • 2015
  • Bacillus subtilis HK176 with high fibrinolytic activity was isolated from cheonggukjang, a Korean fermented soyfood. A gene, aprE176, encoding the major fibrinolytic enzyme was cloned from B. subtilis HK176 and overexpressed in E. coli BL21(DE3) using plasmid pET26b(+). The specific activity of purified AprE176 was 216.8 ± 5.4 plasmin unit/mg protein and the optimum pH and temperature were pH 8.0 and 40℃, respectively. Error-prone PCR was performed for aprE176, and the PCR products were introduced into E. coli BL21(DE3) after ligation with pET26b(+). Mutants showing enhanced fibrinolytic activities were screened first using skim-milk plates and then fibrin plates. Among the mutants, M179 showed the highest activity on a fibrin plate and it had one amino acid substitution (A176T). The specific activity of M179 was 2.2-fold higher than that of the wild-type enzyme, but the catalytic efficiency (kcat/Km) of M179 was not different from the wild-type enzyme owing to reduced substrate affinity. Interestingly, M179 showed increased thermostability. M179 retained 36% of activity after 5 h at 45℃, whereas AprE176 retained only 11%. Molecular modeling analysis suggested that the 176th residue of M179, threonine, was located near the cation-binding site compared with the wild type. This probably caused tight binding of M179 with Ca2+, whichincreased the thermostability of M179.

Application of lactic acid bacteria producing antifungal substance and carboxylesterase on whole crop rice silage with different dry matter

  • Lee, Seong Shin;Paradhipta, Dimas Hand Vidya;Lee, Hyuk Jun;Joo, Young Ho;Noh, Hyeon Tak;Choi, Jeong Seok;Ji, Keum Bae;Kim, Sam Churl
    • Animal Bioscience
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    • v.34 no.6
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    • pp.1029-1037
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    • 2021
  • Objective: This study was conducted to investigate effects of antifungal substance and carboxylesterase-producing inoculant on fermentation indices and rumen degradation kinetics of whole crop rice (WCR) silage ensiled at different dry matter (DM) contents. Methods: Dual-purpose inoculants, Lactobacillus brevis 5M2 and Lactobacillus buchneri 6M1, confirmed both activities of antifungal and carboxylesterase in the previous study. The WCR at mature stage was chopped, and then wilted to obtain three different DM contents consisting of 35.4%, 43.6%, and 51.5%. All WCR forages were applied distilled water (CON) or mixed inoculants with 1:1 ratio at 1×105 colony forming unit/g (INO), and ensiled into 20 L mini silo (5 kg) in quadruplicates for 108 d. Results: The INO silages had lower lactate (p<0.001) and butyrate (p = 0.022) with higher acetate (p<0.001) and propionate (p<0.001) than those of CON silages. Ammonia-N (p<0.001), lactate (tendency; p = 0.068), acetate (p = 0.030), and butyrate (p<0.001) concentrations of INO silages decreased linearly with increasing DM content of WCR forage. The INO silages presented higher lactic acid bacteria (p<0.001) with lower molds (p<0.001) than those of CON silages. Yeasts (p = 0.042) and molds (p = 0.046) of WCR silages decreased linearly with increasing DM content of WCR forage. In the rumen, INO silages had higher the total degradable fraction (p<0.001), total volatile fatty acid (tendency; p = 0.097), and acetate (p = 0.007), but lower the fractional degradation rate (p = 0.011) and propionate (p<0.001) than those of CON silage. The total degradable fraction (p<0.001), total volatile fatty acid (p = 0.001), iso-butyrate (p = 0.036), and valerate (p = 0.008) decreased linearly with increasing DM content of WCR forage, while the lag phase (p<0.001) was increased linearly. Conclusion: This study concluded that application of dual-purpose inoculants on WCR silage confirmed antifungal and carboxylesterase activities by inhibiting mold and improving rumen digestibility, while increase of wilting times decreased organic acids production and rumen digestibility.

Performance Evaluation of a Driving Power Transmission System for 50 kW Narrow Tractors

  • Hong, Soon-Jung;Ha, Jong-Kyou;Kim, Yong-Joo;Kabir, Md. Shaha Nur;Seo, Young Woo;Chung, Sun-Ok
    • Journal of Biosystems Engineering
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    • v.43 no.1
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    • pp.1-13
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    • 2018
  • Purpose: The development of compact tractors that can be used in dry fields, greenhouses, and orchards for pest control, weeding, transportation, and harvesting is necessary. The development and performance evaluation of power transmission units are very important when it comes to tractor development. This study evaluates the performance of a driving power transmission unit of a 50 kW multi-purpose narrow tractor. Methods: The performance of the transmission and forward-reverse clutch, which are the main components of the driving power transmission unit of multi-purpose narrow tractors, was evaluated herein. The transmission performance was evaluated in terms of power transmission efficiency, noise, and axle load, while the forward-reverse clutch performance was evaluated in terms of durability. The transmission's power transmission efficiency accounts for the measurement of transmission losses, which occur in the transmission's gear, bearing, and oil seal. The motor's power was input in the transmission's input shaft. The rotational speed and torque were measured in the final output shaft. The noise was measured at each speed level after installing a microphone on the left, right, and upper sides. The axle load test was performed through a continuous equilibrium load test, in which a constant load was continuously applied. The forward-reverse clutch performance was calculated using the engine torque to axle torque ratio with the assembled engine and transmission. Results: The loss of power in the transmission efficiency test of the driving power unit was 6.0-9.7 kW based on all gear steps. This loss of horsepower was equal to 11-18% of the input power (52 kW). The transmission efficiency of the driving power unit was 81.5-89.0%. The noise of the driving power unit was 50-57 dB at 800 rpm, 70-77 dB at 1600 rpm, and 76-83 dB at 2400 rpm. The axle load test verified that the input torque and axle revolutions were constant. The results of the forward-reverse clutch performance test revealed that hydraulic pressure and torque changes were stably maintained when moving forward or backward, and its operation met the hydraulic design standards. Conclusions: When comprehensively examined, these research results were similar to the main driving power transmission systems from USA and Japan in terms of performance. Based on these results, tractor prototypes are expected to be created and supplied to farmhouses after going through sufficient in-situ adaptability tests.