• 제목/요약/키워드: Natural reading

검색결과 205건 처리시간 0.03초

일기속담에 대한 중.고등학생들의 인식과 과학수업에의 이용 (A Study on Secondary School Students' Recognition on Weather Proverbs and Application to Science Teaching)

  • 국동식;이철우
    • 대한지구과학교육학회지
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    • 제1권1호
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    • pp.85-98
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    • 2008
  • Though the investigation of the suggested references proverbs related weather were collected and considered the probability of the usage on science instruction. The results are as follows. 130 proverbs related to weather were collected through the investigation of the suggested references. Most of weather proverbs are based on the states of sky, clouds, wind, precipitation, actions of animal, states of plants and the condition of people in daily life. they were classified according to weather types, natural phenomena and seasons. According to the results of analysing the students' recognition and interests on weather proverbs, most of students heard weather proverbs in their elementary school years firstly through their parents, books, and teachers. However they have only heard a few. Also many students also tend to think weather proverbs have a scientific base because weather proverbs have been told by many people through the ancient time and correspond to their personal experiences. Students responded that weather proverbs are useful for science learning on weather and can teach heritage and wisdom. After reading the suggested weather proverbs, their interests on weather proverbs were increased more than before reading. This is one of reasons why weather proverbs can be introduced to science classes. Weather proverbs were considered related to science curriculum. The third grade has a Unit "Fine days and Cloudy days", the fifth grade, "Unit of Weather Change", the Sixth grade, "Unit of Weather Forecast" , the Ninth grade, "Unit of Water cycle and Weather Change" and the tenth grade has "Unit of Earth". So the author consider that weather proverb materials can be used so effectively to bring about interest and motive in science learning.

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슬림형 광 디스크 드라이브의 축방향 진동에 대한 실험적 해석 (Experimental Analysis of Axial Vibration in Slim-type Optical Disc Drive)

  • 박대경;전규찬;이성진;장동섭
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.694-699
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    • 2002
  • As the demand for slim laptops requires ion'-height optical disc drives, vibration problems of optical disc drives are of great concern. Additionally, with the decrease of a track width and a depth of focus in high density drives, studies on vibration resonance between mechanical parts become more important. From the vibration point of view, the performance of optical disc drives is closely related with the relative displacement between a disc and an objective lens which is controlled by servo mechanism. In other words, to read and write data properly, the relative displacement between an optical disc and an objective lens should be within a certain limit. The relative displacement is dependent on not only an anti-vibration mechanism design but also servo control capability. Good servo controls can make compensation for poor mechanisms, and vice versa. In a usual development process, robustness of the anti-vibration mechanism is always verified with the servo control of an objective lens. Engineers partially modify servo gain margin in case of a data reading error. This modification cannot correct the data reading error occasionally and the mechanism should be redesigned more robustly. Therefore it is necessary to verify a mechanism with respect to the possible servo gain plot. In this study we propose the experimental verification method far anti-vibration mechanism with respect to the existing servo gain plot. This method verifies axial vibration characteristics of optical disc drives on the basis of transmissibility. Using this method, we verified our mechanism and modified the mechanism for better anti-vibration characteristics.

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슬림형 광 디스크 드라이브의 축방향 진동에 대한 실험적 해석 (Experimental Analysis of Axial Vibration in Slim-type Optical Disc Drive)

  • 박대경;전규찬;이성진;장동섭
    • 한국소음진동공학회논문집
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    • 제12권11호
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    • pp.833-839
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    • 2002
  • As the demand for slim laptops requires low-height optical disc drives, vibration problems of optical disc drives are of great concern. Additionally, with the decrease of a track width and a depth of focus in high density drives, studies on vibration resonance between mechanical parts become more important. From the vibration point of view, the performance of optical disc drives is closely related with the relative displacement between a disc and an objective lens which is controlled by servo mechanism. In other words, to read and write data properly, the relative displacement between an optical disc and an objective lens should be within a certain limit. The relative displacement is dependent on not only an anti-vibration mechanism design but also servo control capability. Good servo controls can make compensation for poor mechanisms, and vice versa. In a usual development process, robustness of the anti-vibration mechanism is always verified with the servo control of an objective lens. Engineers partially modify servo gain margin in case of a data reading error. This modification cannot correct the data reading error occasionally and the mechanism should be redesigned more robustly. Therefore it is necessary to verify a mechanism with respect to the possible servo gain plot. In this study we propose the experimental verification method for anti-vibration mechanism with respect to the existing servo gain plot. Thismethod verifies axial vibration characteristics of optical disc drives on the basis of transmissibility. Using this method, we verified our mechanism and modified the mechanism for better anti-vibration characteristics.

나이 듦의 상처 극복을 위한 독서치료 (Bibliotherapy for Aging)

  • 장덕현;장영남
    • 한국비블리아학회지
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    • 제17권1호
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    • pp.201-221
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    • 2006
  • 독서치료는 책읽기를 통하여 마음의 변화를 일으키도록 유도함으로써 사람들이 가지고 있는 마음의 상처를 치유하고 삶의 질을 향상시킬 수 있도록 하는 방법이다. 이 연구에서는 독서치료적 접근법을 통하여 나이 듦(Aging)에서 오는 변화를 수용하고 중년 이후의 삶이 야기하는 마음의 상처를 현명하게 극복하도록 하기 위한 이론적 기반을 제시하였다. 이를 위하여 5명의 대상자를 선정한 후 이들에게 적절한 도서들을 추천하였다. 이들이 책읽기를 통하여 나이 듦과 함께 찾아오는 신체적, 인지적, 사회적 변화에 너그러워지고 마음의 상처가 치유되는 경험을 하게 되는 과정을 실제적 사례를 통하여 고찰하였다. 그리고, 대상자들이 나이 듦에서 오는 신체적 기능 저하, 가족들로부터의 괴리감 사회적 무능력감 등의 상처를 발견하고 선정된 권장도서를 읽음으로써 자신의 문제를 객관적으로 이해하게 되고 자신의 아픔을 통찰하게 되어 마음의 안정을 느끼게 되는 과정을 서술하였다.

A Phi Class Glutathione S-transferase from Oryza sativa (OsGSTF5): Molecular Cloning, Expression and Biochemical Characteristics

  • Cho, Hyun-Young;Lee, Hae-Joo;Kong, Kwang-Hoon
    • BMB Reports
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    • 제40권4호
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    • pp.511-516
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    • 2007
  • A glutathione S-transferase (GST) related to the phi (F) class of enzymes only found in plants has been cloned from the Oryza sativa. The GST cDNA was cloned by PCR using oligonucleotide primers based on the OsGSTF5 (GenBank Accession No. $\underline{AF309382}$) sequences. The cDNA was composed of a 669-bp open reading frame encoding for 223 amino acids. The deduced peptide of this gene shared on overall identity of 75% with other known phi class GST sequences. On the other hands, the OsGSTF5 sequence showed only 34% identity with the sequence of the OsGSTF3 cloned by our previous study (Cho et al., 2005). This gene was expressed in Escherichia coli with the pET vector system and the gene product was purified to homogeneity by GSH-Sepharose affinity column chromatography. The expressed OsGSTF5 formed a homo-dimer composed of 28 kDa subunit and its pI value was approximately 7.8. The expressed OsGSTF5 displayed glutathione conjugation activity toward 1-chloro-2,4-dinitrobenzene and 1,2-epoxy-3-(p-nitrophenoxy)propane and glutathione peroxidase activity toward cumene hydroperoxide. The OsGSTF5 also had high activities towards the herbicides alachlor, atrazine and metolachlor. The OsGSTF5 was highly sensitive to inhibition by S-hexylGSH, benastatin A and hematin. We propose from these results that the expressed OsGSTF5 is a phi class GST and appears to play a role in the conjugation of herbicide and GPOX activity.

Klebsiella sp. Sc가 생산하는 β-xylosidase의 분리, 정제 및 특성 (Isolation, Purification and Characterization of the β-Xylosidase from Klebsiella sp. Sc.)

  • 이용석;박인혜;안순철;최용락
    • 생명과학회지
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    • 제20권12호
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    • pp.1801-1806
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    • 2010
  • Klebsiella sp. Sc로부터 birchwood xylan을 분해하는 $\beta$-xylosidase를 분리하였다. 이 $\beta$-xylosidase는 63 kDa의 분자량을 가지는 559개의 아미노산을 암호화하며 1,680개의 뉴클레오타이드로 구성 되는 것으로 밝혀졌다. 기존에 밝혀진 세균성 $\beta$-xylosidase와 상동성을 비교해 보았을 때, Klebsiella oxytoca (KOX)와 90% identities와 95% positives를 나타내었으며 Lactobacillus lactis (LAC, 82%, 90%), Bacillus longum (BLON, 69%, 81%) 그리고 Escherichia coli (ECOLI, 47%, 63%)를 나타내었다. 분리된 $\beta$-xylosidase는 GST-fusion 정제 시스템을 이용하여 순수 정제하였다. 이 효소 활성의 최적 pH는 6.6이었으면 최적 온도는 $55^{\circ}C$였다. TLC를 통해 효소 분해 산물을 관찰한 결과, xylobiose를 분해하여 xylose를 생산하는 것을 관찰 할 수 있었다.

Molecular Cloning of Two cDNAs Encoding an Insecticidal Toxin from the Spider, Araneus ventricosus, and Construction of a Recombinant Baculovirus Expressing a Spider Toxin

  • Chung, Eun-Hwa;Lee, Kwang-Sik;Han, Ji-Hee;Je, Yeon-Ho;Chang, Jin-Hee;Roh, Jong-Yul
    • International Journal of Industrial Entomology and Biomaterials
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    • 제4권1호
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    • pp.43-49
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    • 2002
  • We have cloned cDNAs encoding toxin from the spider, Araneus ventricosus, and constructed a recombinant baculovirus expressing the insecticidal toxin. The cDNAs encoding toxin were cloned from the cDNA library of A. ventricosus. Sequence analysis of the cDNAs encoding the toxin of A. ventricosus revealed that the 240 bp cDNA for AvTox-1 and 192 bp cDNA for AvTox-2 have an open reading frame of 80 and 64 amino acid residues, respectively. The deduced protein sequence of the toxin genes of AvTox-1 and AvTox-2 was aligned to that of the snack Anemonia sulcata and scorpion Centruroides limpidus limpidus, respectively. Northern blot analysis indicated that AvTox-2 toxin gene showed a fat body-spe-cific expression pattern at the transcriptional level. Furthermore, we have explored the possibility of improving baculovirus by incorporating the A. vontricosus toxin gene into Bombyx mori nuclear polyhedrosis virus genome under the control of polyhedrin promoter, The AvTox-2 toxin gene was expressed as approximately 5.8 kDa band in the recombinant baculovirus-injected silkworm larvae. Bioassays with the recombinant virus expressing AvTox-2 on 5th instar silkworm larvae demonstrated a decrease in the time to kill $(LT_{50} days)$ compared to wild-type BmNPV-Kl $(LT_{50} 6.72 days)$ in the injection of 10 viruses. These results indicate that A. ventricosus toxin is a novel member of the spider toxin family, suggesting that the toxin gene can be used in recombinant baculoviruses to reduce insect feeding damage and increase the speed of insect kill.

A Comparison between Low- and High-Passage Strains of Human CytomegalovirusS

  • Wang, Wen-Dan;Lee, Gyu-Cheol;Kim, Yu Young;Lee, Chan Hee
    • Journal of Microbiology and Biotechnology
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    • 제26권10호
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    • pp.1800-1807
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    • 2016
  • To understand how human cytomegalovirus (HCMV) might change and evolve after reactivation, it is very important to understand how the nucleotide sequence of cultured HCMV changes after in vitro passaging in cell culture, and how these changes affect the genome of HCMV and the consequent variation in amino acid sequence. Strain JHC of HCMV was propagated in vitro for more than 40 passages and its biological and genetic changes were monitored. For each passage, real-time PCR was performed in order to determine the genome copy number, and a plaque assay was employed to get virus infection titers. The infectious virus titers gradually increased with passaging in cell culture, whereas the number of virus genome copies remained relatively unchanged. A linear correlation was observed between the passage number and the log10 infectious virus titer per virus genome copy number. To understand the genetic basis underlying the increase in HCMV infectivity with increasing passage, the whole-genome DNA sequence of the high-passage strain was determined and compared with the genome sequence of the low-passage strain. Out of 100 mutations found in the high-passage strain, only two were located in an open reading frame. A G-T substitution in the RL13 gene resulted in a nonsense mutation and caused an early stop. A G-A substitution in the UL122 gene generated an S-F nonsynonymous mutation. The mutations in the RL13 and UL122 genes might be related to the increase in virus infectivity, although the role of the mutations found in noncoding regions could not be excluded.

Expression of Human Papillomavirus Type 16, Prototype and Natural Variant E7 Proteins using Baculovirus Expression System

  • Han, Hee-Sung;Kee, Sun-Ho;Hwang, Soon-Bong;Kim, Hyung-Jun;Cho, Kyung-A;Kim, Yoon-Won;Cho, Min-Kee;Chang, Woo-Hyun
    • 대한바이러스학회지
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    • 제28권1호
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    • pp.53-62
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    • 1998
  • Human papillomavirus (HPV) 16, E7 proteins derived from the prototype (Bac73) and natural variant (Bac101) E7 open reading frame were produced in Sf9 insect cells. The variant E7 gene occurred naturally by substitution mutation at the position of 88 nucleotide, resulting serine instead of asparagine. Using E7 specific monoclonal antibody (VD6), both E7 proteins were identified in recombinant baculovirus infected SF9 cells. Radiolabelling and immunoprecipitation analysis revealed that both E7 proteins were phosphoproteins. Immunostaining result showed that E7 proteins were mainly localized in the cytoplasm. Nuclear form of E7 proteins was also detected after a sequential fractionation procedure for removing chromatin structure. Considering that the VD6 recognition site in E7 protein is located within 10 amino acid at the N-terminus, this region appears to be blocked by the nuclear component. Western blot analysis revealed that nuclear form was more abundant than cytoplasmic E7 proteins. Time course immunostaining showed that the primary location of E7 protein was the nucleus and exported to the cytoplasm as proteins were accumulated. These events occurred similarly in both Bac73 and Bac101 infected Sf9 cells, suggesting that these two proteins may have similar biological functions.

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The Complete Nucleotide Sequence of a Korean Isolate Bean yellow mosaic virus from Freesia sp. and Comparison to Other Potyviruses

  • Choi, Sun-Hee;Yoon, Ju-Yeon;Ryu, Ki-Hyun;Choi, Seung-Kook
    • 식물병연구
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    • 제19권2호
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    • pp.77-83
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    • 2013
  • Bean yellow mosaic virus (BYMV; genus Potyvirus, family Potyviridae) causes severe losses to various legume species and a number of non-legume species, particularly freesia plants. In a survey of virus diseases in Gyeonggi province, Korea, BYMV isolates were identified from many cultivated freesia species. Here, we determined the complete nucleotide sequences of a BYMV freesia isolate (BYMV-Fr; accession number FJ492961). BYMV-Fr genome consists of 9,545 nucleotides (nt) excluding the poly (A) tail and encodes 3,057 amino acid (aa), with an AUG start and UAG stop codon, containing one open reading frame typical of a potyvirus polyprotein. The polyprotein of BYMV-Fr was divided to ten proteins and the cleavage sites of each protein were determined. The coat protein (CP) and polyprotein of BYMV-Fr were compared at the aa level with those of the previously reported 4 BYMV isolates. BYMV-Fr shared 90.1 to 97.1 and 91.0 to 92.5% at the CP and polyprotein homology. Interestingly, BYMV-Fr showed identities of a lower level at the nt level of 5' noncoding region (61.4 to 67.6%) and at the aa level of P1 (71.4 to 72.8%), comparing with four BYMV isolates. Based on the aa sequence diversity of CP and polyprotein, phylogenetic analysis with the four BYMV isolates showed two distinct groups and BYMV-Fr and most BYMV isolates were most closely related to the clover yellow vein virus among 52 potyviruses. To our knowledge, this is the first report of the complete genome sequence of BYMV freesia strain.