• Title/Summary/Keyword: EFL

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Isolation and characterization of cellulolytic bacteria, Bacillus sp. EFL1, EFL2, and EFP3 from the mixed forest (혼효림으로부터 셀룰로오스분해 박테리아 분리 및 효소학적 특성규명)

  • Park, Hwa Rang;Oh, Ki-Cheol;Kim, Bong-Gyu
    • Journal of Applied Biological Chemistry
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    • v.61 no.1
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    • pp.59-67
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    • 2018
  • This study was conducted to isolate the cellulolytic bacteria able to grow on LB- Carboxymethyl cellulose (CMC) agar trypan blue medium from the mixed forest and Larix leptolepis stands. Three bacterial strains with high activity against both CMC and xylan were isolated. Both API kit test and 16S rRNA gene sequence analysis revealed that the three different isolates belong to the gene Bacillus. Therefore, the isolates named as Bacillus sp. EFL1, Bacillus sp. EFL2, and Bacillus sp. EFP3. The optimum growth temperature of Bacillus sp. EFL1, EFL2, and EFP3 were $37^{\circ}C$. The optimum temperature for CMCase and xylanase from Bacillus sp. EFL1 were $50^{\circ}C$. The optimum pH of Bacillus sp. EFL1 xylanase was pH 5.0 but the optimum pH of CMCase from Bacillus sp. EFL1 was pH 6.0. The optimum temperature of CMCase and xylanase from Bacillus sp. EFL2 was $60^{\circ}C$, respectively. The optimum pH of CMCase of Bacillus sp. EFL2 was 5.0, whereas xylanase showed high activity at pH 3.0-9.0. The optimum temperature for CMCase and xylanase of Bacillus sp. EFP3 was $50^{\circ}C$. The optimum pH for CMCase and xylanse was 5.0 and 4.0, respectively. CMCases from Bacillus sp. EFL1, EFL2, and EFP3 were thermally unstable. Although xylanase from Bacillus sp. EFL1 and EFP3 showed to be thermally unstable, xylanase from Bacillus sp. EFL2 showed to be thermally stable. Therefore, Bacillus sp. EFL2 has great potential for animal feed, biofuels, and food industry applications.

Lethal (2) Essential for Life [l(2)efl] Gene in the Two-spotted Cricket, Gryllus bimaculatus (Orthoptera: Gryllidae) (쌍별귀뚜라미(Gryllus bimaculatus)의 l(2)efl cDNA 클로닝과 발현분석)

  • Kwon, Kisang;Lee, Nuri;Kwon, O-Yu
    • Journal of Life Science
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    • v.31 no.7
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    • pp.671-676
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    • 2021
  • A cDNA encoding the protein lethal (2) essential for life [l(2)efl] was cloned from Gryllus bimaculatus and named GBl(2)efl. This protein is composed of 189 amino acids, including an N-glycosylation site and 15 phosphorylation sites. Its predicted molecular mass is 21.19 kDa, with a theoretical isoelectric point of 6.2. The secondary structure of GBl(2)efl was predicted from the identification of random coils (56.08%), alpha helices (22.22%), extended strands (17.99%), and beta turns (3.7%) through sequence analyses. A homology analysis revealed that GBl(2)efl exhibited a high similarity with other species at the amino acid level, ranging from 52% to 69%. While GBl(2)efl mRNA expression was higher in the dorsal longitudinal flight muscle following a three-day starvation and in the Malpighian tubules following a one-day starvation, no changes in expression were detected in other tissues. Furthermore, tunicamycin-induced endoplasmic reticulum (ER) stress resulted in an approximately 1.8-fold higher expression in the fat body compared with the wild type.

A Case Study on College EFL Readers: Awareness, Experiences, and Processes

  • Chin, Cheongsook
    • English Language & Literature Teaching
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    • v.17 no.3
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    • pp.1-25
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    • 2011
  • This research primarily aimed to investigate proficient and less proficient EFL readers' awareness and experiences about learning to read and reading in English. The secondary purpose was to explore the participants' reading strategies, and to discover how the genres of English texts influence their reading processing behaviors. The participants consisted of four college students in engineering aged 21-25 years. Three data sources were employed: questionnaires, interviews, and think-alouds. The findings revealed that: (1) the proficient EFL readers judged themselves to be good readers, while the less proficient EFL readers judged themselves to be fair readers; (2) unknown vocabulary was perceived to be the major impediment to reading comprehension; the think-aloud data, however, demonstrated that unknown vocabulary did not significantly interfere with their reading comprehension; (3) regardless of the genre of the text, the participants employed similar reading strategies; (4) the participants were more likely to tolerate ambiguity and predict the content when reading the narrative text than the expository text; (5) there was no set of strategies that distinguished proficient EFL readers from less proficient EFL readers; and (6) when identifying problems, the proficient EFL readers used fix-up strategies more effectively and were better able to provide satisfactory solutions than their counterparts. Pedagogical implications for EFL reading instruction are discussed.

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Study on Templates and Models for Learning & Business Activity Integration using uEFL(Universal Engine for Learning) (학습, 기업 활동 통합 지원 모델 및 템플릿의 연구 - uEFL (Universal Engine For Learning)의 활용을 중심으로 -)

  • Lee, Ho-Gun;Ho, Won;Jang, Jin-Young
    • International Commerce and Information Review
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    • v.10 no.4
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    • pp.81-96
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    • 2008
  • uEFL is an open source solution to integrate general business/learning activities and processes. uEFL is originally developed to adopt LD (Learning Design) specification, which represents learning as various combination of learning activities with learning conditions and outcomes. Learning activities are described with participant's role, learning environment, and contextual sequence. This viewpoint resembles BPM (Business Process Modeling). uEFL can convert LD to BPM description. uEFL engine can run converted LD activity with other business activities. This paper presents 4 templates and 2 sample models for uEFL. The templates and models will show how learning activities can be integrated with business activities efficiently.

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The Extent of EFL Adult Learners Access to UG

  • Kang, Ae-Jin
    • Korean Journal of English Language and Linguistics
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    • v.2 no.3
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    • pp.305-327
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    • 2002
  • This paper is in line with the attempts to examine two assumptions implied about the role of Universal Grammar (UC) in nonnative language acquisition: Are the EFL learners at disadvantage in acquiring UC-driven knowledge? Are there critical period effects in EFL learning? Based on the research with the seven studies of ESL and EFL adult learners performance on the Subjacency violation sentences, the paper investigates the extent to which the EFL adult learners can attain UG-driven knowledge represented by the Subjacency Principle. It also makes comparison of the EFL learners level of access to UG with that of their counterparts, the ESL learners. The research findings suggests that the EFL environment doesn't prevent the learners from acquiring target grammar in UG domain. That is, the current paper strongly suggests that the EFL adult-learners be able to acquire UG-driven knowledge to a considerable extent, at least as high as the ESL adult learners can attain. For the interpretation of the research results of the seven studies, Constructionist Hypothesis (CH) supported by a Minimalist Program (MP) assumption is employed. CH seems more plausible to account not only for incomplete acquisition observed among the beginning and intermediate level learners but also for the native-like competence acquired by advanced level L2 learners.

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Comparative Study on English Proficiency of Children of ESL(English as a Second Language) & EFL(English as Foreign Language) Learning Programs (ESL과 EFL학습프로그램에 의한 아동 영어능력 비교연구)

  • Yoon, Eu-Gene;Chong, Young-Sook
    • Korean Journal of Human Ecology
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    • v.14 no.6
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    • pp.961-972
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    • 2005
  • The purpose of this study is to investigate the improvement of English proficiency of children in the ESL and EFL learning style classrooms through the experiment method. The results of this research are as follows: first, the scores of listening and speaking and the perception of alphabets in the ESL program are higher than that in the EFL program. This means that learning in the ESL style classroom is the better way to improve English skills than in the EFL style classroom, which is common in Korea. Second, there is no difference in the English listening and speaking skills and the perception of the English alphabets between the two gender groups in the ESL & EFL style classrooms. These results suggest that the target language may be used in the English classrooms by the teachers and the students with the materials, books, and equipment are English. Teachers are expected to be in charge of playing decisive roles as demonstrators of speech, models and correctors of pronunciation and providers of materials including TV, VCR, CD players, and cassette recorders, etc.

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Effects of Different Types of Chatbots on EFL Learners' Speaking Competence and Learner Perception (서로 다른 챗봇 유형이 한국 EFL 학습자의 말하기능력 및 학습자인식에 미치는 영향)

  • Kim, Na-Young
    • Cross-Cultural Studies
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    • v.48
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    • pp.223-252
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    • 2017
  • This study explores effects of two types of chatbots - voice-based and text-based - on Korean EFL learners' speaking competence and learner perception. Participants were 80 freshmen students taking an English-speaking class at a university in Korea. They were divided into two experimental groups at random. During the sixteen-week experimental period, participants engaged in 10 chat sessions with the two different types of chatbots. To take a close examination of effects on the improvement of speaking competence, they took the TOEIC speaking test as pre- and post-tests. Structured questionnaire-based surveys were conducted before and after treatment to determine if there are changes in perception. Findings reveal two chatbots effectively contribute to improvement of speaking competence among EFL learners. Particularly, the voice-based chatbot was as effective as the text-based chatbot. An analysis of survey results indicates perception of chatbot-assisted language learning changed positively over time. In particular, most participants preferred voice-based chatbot over text-based chatbot. This study provides insight on the use of chatbots in EFL learning, suggesting that EFL teachers should integrate chatbot technology in their classrooms.

L2 Reader's Critical Reading Interpretation

  • Kim, Young-Mi
    • English Language & Literature Teaching
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    • v.12 no.1
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    • pp.1-27
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    • 2006
  • This study investigated how EFL readers critically read texts which are written in English. Although critical reading has been discussed in advanced EFL and ESL contexts there has not been much research on the critical reading of beginning EFL learners. Many educators are recommending that a critical perspective be adopted so that L2 learners can become empowered rather than indoctrinated. In this study, the researcher has examined the critical reading practices of five beginning level EFL readers in Korea and five first language readers of English in the United States as they read a news editorial article. The significant findings were discussed related to critical reading practice of L2 readers. The findings of the study can help the educators in English education in improving the curriculum, the teaching methodology and the learning theory for EFL reading for critical reading.

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The critical period in Korean EFL contexts and UG (한국인 EFL 학습자의 결정적 시기와 보편문법)

  • Hahn, Hye-Ryeong
    • English Language & Literature Teaching
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    • no.6
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    • pp.219-239
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    • 2000
  • There has been a growing enthusiasm in Korea for the early education of English as a foreign language (EFL). The present study examined the validity of the Critical Period Hypothesis in terms of the Universal Grammar (UG), in three different types of learning contexts - first language (L1), second language (SL), and foreign language (FL) learning contexts. While previous research findings in L1 and SL learning contexts suggest that UG principles and parameters are accessible to language learners only for the early years of lifetime, this article argues that their results - and even the methods - cannot be applied to EFL settings and that independent studies on the EFL context are, required. It also proposes the recent UG notion of functional categories as the most appropriate subject in the discussion of Korean EFL learners' access to UG. Findings on foreign language contexts, including the author's own, strongly indicate that UG is not sensitive to learners' starting ages in FL settings. If young children in FL contexts cannot develop their interlanguage grammar based on UG, the existing teaching methods for young children should be revised.

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EFL Learners' Perceptions on English Writing Tasks and Teacher Feedback

  • Chin, Cheong-Sook
    • English Language & Literature Teaching
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    • v.13 no.1
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    • pp.1-26
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    • 2007
  • This study aimed to investigate how EFL learners perceived English writing tasks and teachers' written feedback. The subjects were 82 mixed major college EFL students aged 19-24; the majority were freshmen females. Based on the scores estimated from the essay evaluation test, they were placed into two groups (proficienand less-proficient writers) and responded to an in-class questionnaire. The results indicated that: (1) regardless of writing proficiency, a large number of the students felt that they were just fair writers, which could be derived from low confidence and high anxiety; (2) grammar and vocabulary were perceived as the main features that determined good EFL writers and also prevented the students from performing the writing task successfully; (3) they believed that teachers' feedback contributed to the development of their English writing skills because it helped them apprehend what to improve or avoid in the future, acquire better English usage, and correct their errors; and (4) the proficient writers were more willing to correct errors themselves after being provided clues than the less-proficient writers. Implications of the findings for EFL classrooms are discussed.

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