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The Drying Characteristics of Cooked-Ginseng Root and Its Shrinkage during Dehydration (증자인삼(蒸煮人蔘)의 건조특성(乾燥特性)과 건조(乾燥)에 수반(隨伴)하는 삼근(蔘根)의 수축(收縮))

  • Chun, Jae-Kun;Park, Hoon;Suh, Chung-Sik
    • Applied Biological Chemistry
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    • v.28 no.3
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    • pp.167-173
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    • 1985
  • Hot air drying characteristics of six year old cooked ginseng root at temperature ranges of $55{\sim}75^{\circ}C$ under 1.8m/sec air velocity and shrinkages accompained were investigated. Drying time to reach equilibrium moisture content of the root takes from 20 to 30 hours, depending on the subjected drying temperatures and root sizes. Drying curve shows that it has two or three falling stages and drying constant are continuously changed. Higher drying constant was observed both at early and late stages of drying. Shrinkage ratio of length, diameters, surface area and volume of the root were 13.0, 39.8, 47.7 and 68.5%, respectively, after 40 hours dry at $55^{\circ}C$. The most of shrinkage was observed at early drying stage.

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The Effect of Interview with Scientist and Engineer on the Science Career Orientation and Image of Scientists (과학기술자와의 인터뷰가 과학 진로 지향 및 과학자 이미지에 미치는 영향)

  • Jeon, Hwa-Young;Lee, Jin-Myung;Hong, Hun-Gi
    • Journal of The Korean Association For Science Education
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    • v.28 no.4
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    • pp.350-358
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    • 2008
  • The purpose of this study was to investigate the effects of interview with a scientist and engineer on service performance assessment on science career orientation and image of scientists. Science track students in the 11th grade carried out the interviews and made powerpoint presentations. After the students' presentation in the chemistry class, the teacher made comments on the contents of the interviews. Students gave presentation in each class for a year. Before starting this assessment, students took science career orientation questionnaire and DAST (draw-a-scientist-test). These two tests were conducted again at the end of the year. The results of this study showed that there was no significant difference between pre- and post-test score for the science career orientation. However, a significant difference was observed in the 'preference for science learning' category. These results showed that the career decision of a high school student has already been fixed rigidly. On the other hand, there was a significant difference (p < 0.01) between pre- and post-test on the image of scientists. This demonstrated that the stereotypic image for a scientist was reduced by the interview performance assessment and that, students came to have an affirmative perception of scientists on service.

In vitro investigation of food effects on human gut microbiota (In vitro 상에서 식품이 장내미생물에 미치는 영향)

  • Jeon, Dabin;Singh, Vineet;Unno, Tatsuya
    • Journal of Applied Biological Chemistry
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    • v.64 no.1
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    • pp.75-81
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    • 2021
  • Recent gut microbiota studies have revealed the important roles of gut microbiota for our health. Increasing numbers of health functional foods have been developed every year. Development of functional food often includes ex- and in-vivo experiment to verify the beneficial effects of the functional food. To investigate effects of functional food on gut microbiota, animal models were often conducted. Beneficial effects of food can be evaluated based on how gut microbiota was shifted by food, which results in either increase in beneficial bacteria, decrease in potentially pathogenic bacteria or both. As animal experiments are generally time-consuming and laborious, we investigate how well in-vitro investigation of fecal microbiota may reflect dietary health benefits. Here, we tested 15 kinds of diets using two human subjects' fecal materials. Our results showed varying gut microbiota shifts according to diets, which suggested generally known beneficial diets (i.e. Kimchi, Chunggukjang) increased Lactobacillus and Bifidobacterium. Therefore, we suggest that in vitro fecal microbiota analysis could be used to evaluate beneficial effects of diets. Moreover, this method may be ideal to establish personalized diet.

The Effect of Recombinant Human Growth Hormone on Growth in Children with Nephropathy Receiving Long-term Steroid Therapy (장기간의 스테로이드 치료를 받고 있는 신병증 환아에서 Recombinant Human Growth Hormone의 효과)

  • Kim, Se-Jin;Kim, Sun-Kyoung;Kim, Sung-Do;Cho, Byoung-Soo
    • Childhood Kidney Diseases
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    • v.10 no.2
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    • pp.142-151
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    • 2006
  • Purpose : Growth retardation is one of the serious problems in children with nephropathy requiring long-term steroid therapy. We observed the efficacy and safety of recombinant human growth hormone(rhGH) on the growth in children with long-term steroid therapy. Methods : We studied 60 children(male 47, female 13) with nephropathy who received rhGH(1 U/kg/week) for more than 0.5 years($1.39{\pm}1.12$). Their mean age was 11.0 years($11.17{\pm}2.62$). They received steroid therapy from January 1987 through July 2005, and the mean duration of steroid therapy was $4.32{\pm}2.97$ years. Among the patients, there were 32 nephrotic syndrome, 9 IgA nephropathy, 4 mesangial proliferative glomerulonephritis, 4 focal segmental glomerulosclerosis, 2 Henoch $Sch\ddot{o}nlein$ nephritis, 2 Alport syndrome and 7 other cases. Data were gathered on the growth parameters, such as growth velocity, height standard deviation score(SDS), IGF-1, IGFBP-3, bone mass density(BMD) and general chemistry changes. Results : Height velocity increased significantly with rhGH therapy from $3.29{\pm}1.95$ to $8.66{\pm}3.75$(cm/yr) and height SDS decreased from $-0.72{\pm}0.93$ to $-1.04{\pm}0.86$ at one year after steroid therapy but increased to $-0.55{\pm}0.96$ at one year after rhGH administration(P<0.05). BMD improved from $0.71{\pm}0.14$ to $0.79{\pm}0.15g/cm^2$(P<0.05). IGF-1 increased from $445.09{\pm}138.01$ to $506.62{\pm}181.31ng/mL$(P<0.05). IGFBP-3 decreased from $4073.75{\pm}700.78$ to $3933.61{\pm}789.25ug/L$ numerically, but there was no statistically significant difference(P=0.533). Conclusion : The administration of rhGH in the short stature patients who received long-term steroid therapy showed improvement in growth parameters such as SDS, growth velocity, and BMD without significant side-effects or changes in the biochemical parameters.

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Effects of Paper Mill Sludge-Fertilizer Application on the Growth Performances of Tree Seedlings (제지(製紙)슬러지 가공비료(加工肥料)의 시용(施用)이 수묘(樹苗)의 생육(生育)에 미치는 영향(影響))

  • Kwon, Ki-Won;Lee, Kyu-Seung
    • Korean Journal of Environmental Agriculture
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    • v.12 no.3
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    • pp.219-229
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    • 1993
  • Effects of paper mill sludge-fertilizers were investigated on the growth performances of tree seedlings under field conditions. Two types of sludge-fertilizers applied were an organic sludge compost and a processed sludge-pellet fertilizer strengthened with several components of organic and inorganic nutrients. Three species of tree seedlings studied were ibota privet(Ligustrum obtusifolium) and yellow poplar(Liriodendron tulipifera) of 1-0 year seedlings and also eastern white pine(Pinus strobus) of 2-2 year seedlings. Nitrogen and phosphorus contents of plot soil treated with sludge compost+sludge-pellet fertilizer+sludge-pellet fertilizer plot were increased to 8 times and 2.6 times as those of control plot, respectively. The growth performances of root collar diameter and seedling height were repeatedly measured up to five times through the growing season and the results were analyzed statistically by analysis of variance of randomized block design and Duncan's multiple range test. The growth performances of dry weight were measured after last fifth measurements.

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Examining Pedagogical Reasoning of Beginning Science Teachers in a Professional Learning Community (교사학습공동체 초임과학교사의 교수학적 추론 탐색)

  • Aeran Choi;Jiye Kim;Jaekyoung Song
    • Journal of the Korean Chemical Society
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    • v.68 no.4
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    • pp.205-220
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    • 2024
  • This study aims to explore characteristics of pedagogical reasoning and action of beginning science teachers that naturally and spontaneously occurs in a professional learning community. Three novice middle school science teachers who majored chemistry education in A college of education, passed the examination for selecting secondary school chemistry teachers, and had a common goal of designing 8th grade science lesson plan voluntarily created a professional learning community and had weekly meetings over a year. Main data sources included transcribed audio-recording of 11 meetings of three science teachers in a professional learning community. Data was analyzed using Shulman's pedagogical reasoning model that includes comprehension, transformation, instruction, evaluation, reflection, and new comprehension to identify characteristics and features of pedagogical reasoning in a professional learning community. Data analysis revealed that pedagogical reasoning in a professional learning community comprises not only preparation, representations, instructional selections, and adaptation but also evaluation, reflection, and new comprehension in transformation stage. Reflection in transformation stage leads teachers to be actively engaged in discussion and get new comprehension on each sub-component(preparation, representations, instructional selections, adaptation, and evaluation) of transformation stage.

THE POSSIBILITIES AND DIFFICULTIES ON R&E ACTIVITY FOR IMPROVING THE PROFESSION SKILLS OF SCIENCE GIFTED TEACHER

  • Park, Sang-Woo;Kim, So-Ah;Park, In-Ho
    • Journal of Gifted/Talented Education
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    • v.14 no.4
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    • pp.1-13
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    • 2004
  • Although over - 600 students in Incheon has been participated in the gifted education programs under the colleges and Office of Education Department every year, it is reported that the number of teachers have insufficient teaching abilities in primary, advanced, and after-advanced gifted classes. The Gifted Education Research Institute in Incheon University introduced R&E activities for the improvement of teachers' abilities in science research and student guiding. Professors in science department conducted the R & E activities to select the research thesis. The professors and the guidance teachers decided the directions of the research, and the guidance teachers who learned from the professors taught 3-5 students to practice the research. Five professor-teacher-student research teams in math, physics, chemistry and biology conducted the research after school and during the vacation for 7 months. The results of the research were submitted to the journals of research activities and the result papers were presented to the seminar. On this research, the possibilities and the difficulties of the R&E activities based of the journals of research activities, oral presentation and the research results reports were analyzed with a purpose of improving the professionalism of the science gifted teachers. Although the professors proposed many difficulties or problems about the R&E activities, the teachers reported that the R & E activities he1ped them to improve their research activities and student guiding techniques. The teachers acquired more knowledge on the principles of the science related areas than before. Moreover, they thought it was very meaningful experience in using the science related instruments, guiding the students' research and writing the research reports. The students also gave the positive responses with the increased interests in new science studies and with the experience of learning the way of research.

Excretion of Toxoplasma gondii oocysts from Feral Cats in Korea

  • Ahn, Kyu-Sung;Ahn, Ah-Jin;Park, Sang-ik;Sohn, Woon-Mok;Shim, Jae-han;Shin, Sung-Shik
    • Parasites, Hosts and Diseases
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    • v.57 no.6
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    • pp.665-670
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    • 2019
  • Sporulated oocysts from the feces of infected cats with Toxoplasma gondii can cause detrimental disease in both humans and animals. To investigate the prevalence of feral cats that excrete T. gondii oocysts in the feces, we examined fecal samples of 563 feral cats over a 3-year period from 2009 to 2011. Oocysts of T. gondii excreted into the feces were found from 4 of 128 cats in 2009 (3.1%) and one of 228 (0.4%) in 2010 while none of the 207 cats in 2010 were found positive with oocysts in their feces, resulting in an overall prevalence rate of 0.89% (5/563) between 2009 and 2011. Among the 5 cats that tested positive with T. gondii oocysts, 4 of the cats were male and 1 was a female with an average body weight of 0.87 kg. Numerous tissue cysts of 60 ㎛ in diameter with thin (<0.5 ㎛) cyst walls were found in the brain of one of the 5 cats on necropsy 2 months after the identification of oocysts in the feces. A PCR amplification of the T. gondii-like oocysts in the feces of the positive cats using the primer pairs Tox-5/Tox-8 and Hham34F/Hham3R confirmed the presence of T. gondii oocysts in the feces. This study provides a good indication of the risk assessment of feral cats in the transmission of T. gondii to humans in Korea.

Analytical Research to Determine the effects of the Components of ONGABO on the Viability of HepG2 Cancer Cells by Using the Sovereign, Minister, Assistant and Courier Principle (君臣佐使論)

  • Shin, Jeong-Hun;Jun, Seung-Lyul;Hwang, Sung-Yeoun;Ahn, Seong-Hun
    • Journal of Pharmacopuncture
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    • v.15 no.4
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    • pp.42-51
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    • 2012
  • Objectives: This study used the basic principle of Oriental medicine, the sovereign, minister, assistant and courier principle (君臣佐使論) to investigate the effects of the component of ONGABO, which is composed of Ginseng Radix (Red Ginseng), Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen and Curcumae tuber on the viability of HepG2 cells. Methods: Single and mixed extracts of the component of ONGABO were prepared by lypohilizing powder of Red Ginseng (6-year root from Kanghwa), Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen, Curcumae Tuber (from Omniherb Co., Ltd., Korea) at the laboratory of herbal medicine in Woosuk University and were eluted after being macerated with 100% ethanol for three days. The cell viability of HepG2 was determined by using an absorptiometric analysis with PrestoBlue (Invitrogen) reagent after the plate had been incubated for 48 hours. All of the experiments were repeated three times to obtain the average value and standard deviation. The statistical analysis was done and the correlation factor was obtained by using Microsoft Office Excel 2007 and Origin 6.0 software. Results: Although Ginseng Radix (Red Ginseng) and Schisandrae Fructus did not enhance the viability of HepG2 cells, they were shown to provide protection of those cells. On the other hand, Angelica Gigantis Radix decreased the viability of HepG2 cells significantly, Cuscuta Semen and Curcumae Tuber had a small or no effect on the viability of HepG2 cells. Conclusions: In the sovereign, minister, assistant and courier principle (君臣佐使論), Ginseng Radix (Red Ginseng) corresponds to the sovereign component because it provides cell protection effects, Angelica Gigantis Radix corresponds to minister medicinal because it kills cells, Schisandrae Fructus corresponds to the assistant medicinal to help red ginseng having cell protect effects. Cuscuta Semen and Curcumae Tuber correspond to the courier medicinal having no effect in cell viability in HepG2. We hope this study provides motivation for advanced research on the sovereign, minister, assistant and courier principle.

Virtual Screening of Tubercular Acetohydroxy Acid Synthase Inhibitors through Analysis of Structural Models

  • Le, Dung Tien;Lee, Hyun-Sook;Chung, Young-Je;Yoon, Moon-Young;Choi, Jung-Do
    • Bulletin of the Korean Chemical Society
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    • v.28 no.6
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    • pp.947-952
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    • 2007
  • Mycobacterium tuberculosis is a pathogen responsible for 2-3 million deaths every year worldwide. The emergence of drug-resistant and multidrug-resistant tuberculosis has increased the need to identify new antituberculosis targets. Acetohydroxy acid synthase, (AHAS, EC 2.2.1.6), an enzyme involved in branched-chain amino acid synthesis, has recently been identified as a potential anti-tuberculosis target. To assist in the search for new inhibitors and “receptor-based” design of effective inhibitors of tubercular AHAS (TbAHAS), we constructed four different structural models of TbAHAS and used one of the models as a target for virtual screening of potential inhibitors. The quality of each model was assessed stereochemically by PROCHECK and found to be reliable. Up to 89% of the amino acid residues in the structural models were located in the most favored regions of the Ramachandran plot, which indicates that the conformation of each residue in the models is good. In the models, residues at the herbicide-binding site were highly conserved across 39 AHAS sequences. The binding mode of TbAHAS with a sulfonylurea herbicide was characterized by 32 hydrophobic interactions, the majority of which were contributed by residue Trp516. The model based on the highest resolution X-ray structure of yeast AHAS was used as the target for virtual screening of a chemical database containing 8300 molecules with a heterocyclic ring. We developed a short list of molecules that were predicted to bind with high scores to TbAHAS in a conformation similar to that of sulfonylurea derivatives. Five sulfonylurea herbicides that were calculated to efficiently bind TbAHAS were experimentally verified and found to inhibit enzyme activity at micromolar concentrations. The data suggest that this time-saving and costeffective computational approach can be used to discover new TbAHAS inhibitors. The list of chemicals studied in this work is supplied to facilitate independent experimental verification of the computational approach.