• 제목/요약/키워드: genetics unit

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An Analysis of the Concepts that Should be Taught to Achieve Class Objectives of Genetics Unit in Biology

  • Lim, Soo-Min;Kim, Jeong-A;Sonn, Jong-Kyung;Jeong, Jae-Hoon;Kim, Young-Shin;Song, Ha-Young
    • 한국과학교육학회지
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    • 제29권7호
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    • pp.767-782
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    • 2009
  • The researchers who are studying biology and teachers who are teaching biology think that the genetics-related concepts are highly significant than other concepts in biology. With such background, researches on the identification of major concepts have been under way to guide in biology class. Minimal research has been carried out, however, on what concepts should be taught to achieve the specific objectives of the class in relation to the unit of genetics in middle and high school. Accordingly this study was designed to determine the concepts of genetics that should be taught to achieve the objectives of the genetics unit in secondary school. For this purpose 5 instructional objectives of the genetics unit on the 9th grade and 4 instructional objectives of Biology I were selected and the concepts that were taught to achieve class objectives. The survey was conducted among 114 science teachers from middle schools and 85 biology teachers from high schools. The results indicated that 9.1 and 10.2 concepts on average were taught in the 9th grade and in Biology I respectively. Moreover statistical difference in the number of concepts that were taught according to the teachers' teaching experiences appeared among the middle school teachers (p<.05). But such statistical difference did not appear among the high school teachers (p>.05). Furthermore the concepts for the 9th grade consist of the basic genetics concepts although Biology I concepts were integrated and advanced contents for same concepts. Thus this finding suggests that concepts of genetics units to be taught in middle and high school were in linkage.

Increasing the Triacylglycerol Content in Dunaliella tertiolecta through Isolation of Starch-Deficient Mutants

  • Sirikhachornkit, Anchalee;Vuttipongchaikij, Supachai;Suttangkakul, Anongpat;Yokthongwattana, Kittisak;Juntawong, Piyada;Pokethitiyook, Prayad;Kangvansaichol, Kunn;Meetam, Metha
    • Journal of Microbiology and Biotechnology
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    • 제26권5호
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    • pp.854-866
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    • 2016
  • The production cost of biodiesel from microalgae is still not competitive, compared with that of petroleum fuels. The genetic improvement of microalgal strains to increase triacylglycerol (TAG) accumulation is one way to reduce production costs. One of the most promising approaches is the isolation of starch-deficient mutants, which have been reported to successfully increase TAG yields. To date, such a stable mutant is not available in an oleaginous marine microalga, despite several advantages of using marine species for biodiesel production. Algae in the genus Dunaliella are known to tolerate high salt concentration and other environmental stresses. In addition, the cultivation processes for large-scale outdoor commercialization have been well established for this genus. In this study, Dunaliella tertiolecta was used to screen for starch-deficient mutants, using an iodine vapor-staining method. Four out of 20,016 UV-mutagenized strains showed a substantial reduction of starch content. A significantly higher TAG content, up to 3-fold of the wild-type level, was observed in three of the mutants upon induction by nitrogen depletion. The carotenoid production and growth characteristics of these mutants, under both normal and oxidative stress conditions, were not compromised, suggesting that these processes are not necessarily affected by starch deficiency. The results from this work open up new possibilities for exploring Dunaliella for biodiesel production.

Solution Conformation of an Antimicrobial Peptide Gaegurin 4

  • Suk, Jae-Eun;Baek, Hwa-Jin;Lee, Byeong-Jae;Han, Kyou-Hoon
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 1997년도 학술발표회
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    • pp.13-13
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    • 1997
  • Gaegurin 4 is an antimicrobial peptide found in the skin of a Korean frog, Rana rugosa, known for its "wound-healing" effect for years. This 37-residue basic peptide binds to cell membranes and forms ion channels like other antimicrobial peptides but does not exhibit hemolytic activity.(omitted)

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Genetic parameters and inbreeding effects for production traits of Thai native chickens

  • Tongsiri, Siriporn;Jeyaruban, Gilbert M.;Hermesch, Susanne;van der Werf, Julius H.J.;Li, Li;Chormai, Theerachai
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권7호
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    • pp.930-938
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    • 2019
  • Objective: Estimate genetic parameters, the rate of inbreeding, and the effect of inbreeding on growth and egg production traits of a Thai native chicken breed Lueng Hang Kao Kabinburi housed under intensive management under a tropical climate. Methods: Genetic parameters were estimated for weight measured at four weekly intervals from body weight at day 1 (BW1D) to body weight at 24 weeks (BW24) of age, as well as weight at first egg, age at first egg (AFE), egg weight at first egg, and total number of eggs (EN) produced during the first 17 weeks of lay using restricted maximum likelihood. Inbreeding depression was estimated using a linear regression of individual phenotype on inbreeding coefficient. Results: Direct additive genetic effect was significant for all traits. Maternal genetic effect and permanent environmental hen effects were significant for all early growth traits, expect for BW24. For BW24, maternal genetic effect was also significant. Permanent environmental hen effect was significant for AFE. Direct heritabilities ranged from 0.10 to 0.47 for growth traits and ranged from 0.15 to 0.16 for egg production traits. Early growth traits had high genetic correlations between them. The EN was lowly negatively correlated with other traits. The average rate of inbreeding for the population was 0.09% per year. Overall, the inbreeding had no effect on body weight traits, except for BW1D. An increase in inbreeding coefficient by 1% reduced BWID by 0.09 g (0.29% of the mean). Conclusion: Improvement in body weight gain can be achieved by selecting for early growth traits. Selection for higher body weight traits is expected to increase the weight of first egg. Due to low but unfavorable correlations with body weight traits, selection on EN needs to be combined with other traits via multi-trait index selection to improve body weight and EN simultaneously.

느타리버섯속(屬)의 DNA 다형성분석(多型性分析)에 영향(影響)을 미치는 PCR 조건(條件) (Parameters Affecting Polymerase Chain Reaction in RAPD Analysis of Pleurotus spp.)

  • 김범기;정미정;이창수;이희경;유영복;유진창
    • 한국균학회지
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    • 제23권3호통권74호
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    • pp.202-208
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    • 1995
  • 본 실험결과 느타리버섯속에서의 재현성 있는 최적 RAPD 조건은 $50\;{\mu}l$ 반응액에서 80 ng template DNA, 30 pmole primer, $200\;{\mu}M$ dNTP, 2 mM $MgCl_2$, 50 mM KCl, 10 mM Tris-HCI(pH 9.0), 0.1% Triton X-100, 1.5 unit Taq polymerase(promega)였다. 여섯 개의 primer가 Pleurotus속 8종의 균주에서 RAPD polymorphism을 보임을 알 수 있었으며, 이들의 염기배열은 PR2(GGG GGG AAG C), PR3(GCG GTT GAG G), PR4(CGC ACC GCA C), PR10(CAA TCG CCG T), PR11(CAG CAC CCA C), PR17(TAG GCG TAT CAG GAG GCC CT)이었다.

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Epidemic Trends of Upper Gastrointestinal Tract Abnormalities: Hospital-based study on Endoscopic Data Evaluation

  • Mohiuddin, Mohammed Khaliq;Chowdavaram, Suman;Bogadi, Varun;Prabhakar, Boddu;Rao, Kondadasula Pandu Ranga;Devi, Suneetha;Mohan, Vasavi
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권14호
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    • pp.5741-5747
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    • 2015
  • Purpose: To understand the epidemiology of different upper gastrointestinal (UGI) tract related abnormalities through endoscopic data analysis. Materials and Methods: A retrospective study of three years from January 2009 to December 2011 was conducted with data from endoscopic surveillance of upper GI tract problems, collected from the Gastroenterology Unit, Osmania General Hospital, Hyderabad. MS excel and Medcalc software (comparison of proportions) were used for data analysis. Results: A total of 10,029 (6,468 in males and 3,561 in females) endoscopies were performed during this three-year period. The male to female ratio was 1.8:1. Overall, ~30% of endoscopies evaluated showed patients with acid peptic disorders, 13.6% with vascular-related abnormalities, 10.6% showed structural abnormalities, followed by 6.3% with malignancies. Burden of malignancies was mostly observed in the older age group (60-69 years). Esophageal cancer cases decreased (p=0.0001) whereas stomach cancers increased over this period (p=0.0345). We also observed an increased incidence of acid peptic disease (APD) (p=0.0036) and gastroesophageal reflux disease (GERD) (p=0.0002) cases during this period. Conclusions: Endoscopic diagnosis is useful for early detection of UGI anomalies and helpful for physicians to manage and treat varied kinds of UGI disorders. Analysis of data revealed changing trends in the incidence of various pathologies of the UGI tract. Functional dyspepsia and GERD definitely reduce the quality of life of the individual. The role of our diverse dietary habits and lifestyle associated with these problems have not yet been established, though there have been reports on the effect of coffee, spicy food, wheat-based diet, screening of UGI pathologies along with collection of complete personal and medical history details, can h elp in correlating the patients' condition with various aspects of lifestyle and diet.

Characterization of the Replication Region of the Enterococcus faecalis Plasmid p703/5

  • Song, Joon-Seok;Park, Jin-Hwan;Kim, Chan-Wha;Kim, Young-Woo;Lim, Wang-Jin;Kim, Ick-Young;Chang, Hyo-Ihl
    • Journal of Microbiology and Biotechnology
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    • 제9권1호
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    • pp.91-97
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    • 1999
  • In this work, a 1.9-kb region of enterococcal plasmid p703/5 was isolated and the nucleotide sequence analysis of the region was performed. One major open reading frame (ORF) was identified encoding a polypeptide of 28 kDa. Database comparisons suggested that the protein showed some homology with other bacterial RepA proteins. Upstream of the ORF, a potential dnaA box, AT-rich region and 22-bp tandemly repeated sequences (DNA iterons), a feature typical for many replication ori sites, were recognized. Deletion analysis using Exonuclease III and several restriction enzymes indicated that the three elements and the gene product from the ORF were essential for replication and that the minimum unit of DNA required for replication resided on the 1.2-kb AvaII subfragment. Thus, this gene product was referred to as RepA.

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