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Conceptualization of an SSI-PCK Framework for Teaching Socioscientific Issues (과학기술 관련 사회쟁점 교육을 위한 교과교육학적 지식(SSI-PCK) 요소에 대한 탐색)

  • Lee, Hyunju
    • Journal of The Korean Association For Science Education
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    • v.36 no.4
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    • pp.539-550
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    • 2016
  • The purpose of the study is to conceptualize SSI-PCK by identifying major components and sub-components to promote science teachers' confidence and knowledge on teaching SSIs. To achieve this, I conducted extensive literature reviews on teachers' perceptions on SSI, case studies of teachers addressing SSIs, SSI instructional strategies, etc. as well as PCK. Results indicate that SSI-PCK include six major components: 1) Orientation for Teaching SSI (OTS), 2) Knowledge of Instructional Strategies for Teaching SSI (KIS), 3) Knowledge of Curriculum (KC), 4) Knowledge of Students' SSI Learning (KSL), 5) Knowledge of Assessment in SSI Learning (KAS), and 6) Knowledge of Learning Contexts (KLC). OTS refers to teachers' instructional goals and intentions for teaching SSIs. Teachers often present a) activity-driven, b) knowledge and higher order thinking skills, c) application of science in everyday life, d) nature of science and technology, e) citizenship and f) activism orientations for teaching SSIs. KIS indicates teachers' instructional knowledge required for effectively designing and implementing SSI lessons. It includes a) SSI lesson design, b) utilizing progressive instructional strategies, and c) constructing collaborative classroom cultures. KC refers to teachers' knowledge on a) connection to science curriculum (horizontal/vertical) and b) connection to other subject matters. KSL refers to teachers' knowledge on a) learner experiences in SSI learning, b) difficulties in SSI learning, and c) SSI reasoning patterns. KAS indicates teachers' knowledge on a) dimensions of SSI learning to assess, and b) methods of assessing SSI learning. Finally, KLC refers to teachers' knowledge on the cultures of a) classrooms, b) schools, and c) community and society where they are located when teaching SSIs.

A Pilot Study of Bone Mineral Density in Men with Chronic Obstructive Pulmonary Disease (남자 만성폐쇄성폐질환 환자들의 골밀도에 대한 예비연구)

  • Bae, Yun Oh;Han, Minsoo;Lee, Seong-Kyu;Kim, Jeong Nyum;Kim, Jeong Sik;Kim, Jinho;Cho, Yongseon;Lee, Yang Deok
    • Tuberculosis and Respiratory Diseases
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    • v.54 no.4
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    • pp.395-402
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    • 2003
  • Background : Patients with chronic obstructive pulmonary disease (COPD) are at increased risk for osteoporosis, which has implications for mobility and even mortality. The goal of this pilot study was to evaluate bone mineral density (BMD) and risk factors for osteoporosis in a limited number of men with COPD. Methods : We checked BMD, $FEV_1$(% of predicted) and investigated risk factors for osteoporosis in 44 male patients with COPD who visited our hospital from January to August 2002. Results : Mean(${\pm}$) age was $69{\pm}9$ yrs, body mass index(BMI) $21{\pm}3kg/m^2$, $FEV_1$ $50{\pm}18%$ of predicted, lumbar spine T-score $-3.0{\pm}1.2$, lumbar spine Z-score $-2.0{\pm}1.2$, and lumbar spine BMD $0.76{\pm}0.13g/cm^2$. Osteoporosis(T-score below -2.5) was present in 27 patients(61.4%) and osteopenia(T-score between -1 and -2.5) in 17(38.6%). None of the patients had normal BMD. There was no relationship between BMD and $FEV_1$(% of predicted). There were significant differences in smoking, alcohol consumption, exercise, cumulative steroid dose, BMI and BMD among the three groups according to $FEV_1$(% of predicted) (group1 : ${\geq}65%$, group2 : 50-64%, group3 : ${\leq}49%$), except age. However, there were no significant differences in these variables between the osteopenia and osteoporosis groups, except BMI. Linear Regression(Stepwise) analysis showed that lumbar BMD was correlated with BMI & exercise. Conclusion : BMD is significantly reduced in men with COPD. There was no relationship between BMD and pulmonary function.

Effects of Dietary Supplementation of Fermented Wild-ginseng Culture By-products on Egg Productivity, Egg Quality, Blood Characteristics and Ginsenoside Concentration of Yolk in Laying Hens (발효 산삼 배양액 부산물 급여가 산란계의 산란율, 계란 품질, 혈액특성 및 난황내 진세노사이드 함량에 미치는 영향)

  • Jang, H.D.;Kim, H.J.;Cho, J.H.;Chen, Y.J.;Yoo, J.S.;Min, B.J.;Park, J.C.;Kim, I.H.
    • Korean Journal of Poultry Science
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    • v.34 no.4
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    • pp.271-278
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    • 2007
  • The present study was conducted to investigate the effects of dietary supplementation of fermented wild-ginseng culture by-product on egg production, egg quality and blood characteristics in laying hens. A total of 216 ISA Brown laying hens, 55 wk of age, were used in the 6-wk feeding trial. Experimental diets were consisted of basal diet (CON), 2.5% fermented wild-ginseng culture by-product replaced lupin in basal diet (WG1) and 5.0% fermented wild-ginseng culture by-product replaced lupin in basal diet (WG2). Birds were randomly allotted to 18 replicate pens. There were 6 replicates per treatment, and 12 laying hens per replicate. Through the 6-wk feeding trial, egg production was significantly increased in WG1 and WG2 treatments compared to CON (P<0.05). Egg weight was significantly higher in WG2 than CON (P<0.05). WG1 resulted higher yolk color than CON (P<0.05). Albumen height and Haugh unit were significantly improve in WG1 compared to WG2 (P<0.05). Red blood cell was significantly lower in WG2 than CON (P<0.05). LDL-cholesterol was significantly decreased in CON compared to WG2 (P<0.05). In conclusion, fermented wild-ginseng culture by-product could improve egg production and egg weight in laying hens.

Community Structure of Forest Vegetation in Mt. Geumsusan belong to Woraksan National Park (월악산국립공원 금수산 산림식생의 군집구조)

  • Kim, Ho-Jin;Shin, Jae-Kwon;Lee, Cheol-Ho;Yun, Chung-Weon
    • Korean Journal of Environment and Ecology
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    • v.31 no.2
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    • pp.202-219
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    • 2017
  • The purpose of this study was to analyze the community structure of forest vegetation in Mt. Geumsusan belong to Woraksan National Park for providing basic information of ecological management. Data were collected by 41 plots from June to November in 2016 using Z-M phytosociology method, which was analyzed with vegetation types, mean importance value and coincidence method. As the results, the forest vegetation was classified into Quercus mongolica community group including Cornus controversa community, Castanea crenata community(Vegetation unit 3), Quercus variabilis community(Vegetation unit 4) and Q. mongolica community(Vegetation unit 5). C. controversa community was divided into two groups such as Ulmus davidiana var. japonica group(Vegetation unit 1) and Parthenocissus tricuspidata group(Vegetation unit 2). Mean importance percentage of vegetation unit 1 was showing Fraxinus rhynchophylla 14.9%, Morus bombycis 8.7% and Acer pictum subsp. mono 8.3%, that of unit 2 was Larix kaempferi 23.2%, C. controversa 20.1% and P. tricuspidata 6.5%, that of unit 3 was Q. mongolica 15.8%, C. crenata 13.4% and F. rhynchophylla 9.8%, that of unit 4 was Q. mongolica 26.6%, Q. variabilis 20.8% and Pinus densiflora 16.7%, that of unit 5 was Q. mongolica 48.3%, Styrax obassia 7.5%, F. rhynchophylla 5.3% in the order, respectively. Each vegetation unit was classified with dependance on environmental factors as 700m of altitude, $20^{\circ}$ of slope degree, middle slope of topography, 20% of bare rock, 30 taxa of present species, 80% of tree layer coverage rate and 20m of tree layer height. In conclusion, it was preferentially considered that development of peculiar and specific management methods with vegetation unit classified above should be needed for ecological and sustainable forest vegetation management.

A Simple Isolating Method of Preantral Follicles from Mouse Ovaries (생쥐 난소에서 Preantral Follice의 단순 분리법)

  • Kim, Ju-Hwan;Park, Kee-Sang;Song, Hai-Bum;Chun, Sang-Sik
    • Clinical and Experimental Reproductive Medicine
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    • v.27 no.3
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    • pp.235-243
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    • 2000
  • Objective: Our present studies were conducted to examine more effective isolating method of preantral follicles from mouse ovaries. Methods: ICR mice (3-6 weeks old) were sacrificed through cervical dislocation and their ovaries were removed and put into watch glasses containing Hams F-10 supplemented with 10% fetal bovine serum (FBS). Preantral follicles were isolated by three different methods; 1) enzymatical method and 2) mincing method, and 3) scraping method. Enzymatical method was carried out as following. Ovaries were bisected with a pair of fine 30G needles. Bisected ovaries were incubated at $37^{\circ}C$ and 5% $CO_2$ incubator in 2-well dish containing Hams F-10 supplemented with collagenase 600 lU/ml and DNAse 20 lU/ml. After 20 min., follicles were isolated by repeated pipetting. Isolated preantral follicles were collected, and the remnant of tissues was placed in incubator and previous procedure was repeated. Mincing method was carried out with a pair of fine 30G needles attached to 1 ml syringes and minced ovary. Scraping method was carried out with a pair of fine 30G needles and scratched to surface of ovary. The differences between isolating methods were analyzed using Student's t-test and Chi-square. Results were considered statistically significant when ${\rho}$ value was less than 0.05. Results: In handling time, mincing or scraping method ($28{\pm}3.42$ min or $16{\pm}1.58$ min) were significantly (p<0.00001) shorter than enzymatical method ($72{\pm}1.69$ min), and scraping method was significantly (p<0.01) shorter than mincing method. Total number of isolated follicles was significantly (p<0.0001) higher in enzymatical method ($49.8{\pm}3.91$) than in mincing or scraping method ($25.3{\pm}2.33$ or $20.5{\pm}1.75$). Isolated follicles in ${\leq}$90${\mu}m$ were significantly (p<0.005) higher in enzymatical method ($15{\pm}1.71$) than in mincing or scraping method ($7.8{\pm}0.98$ or $8.1{\pm}1.31$). In 91~130 ${\mu}m$, isolated follicles were significantly (p<0.0005) higher in enzymatical method ($33{\pm}3.27$) than in mincing or scraping method ($16.3{\pm}1.82$ or $10.7{\pm}1.38$). In ${\geq}$ 131 ${\mu}m$, isolated follicles were not significantly differences between all groups. In equal sizes, the rate of isolated follicles in ${\leq}$ 90 ${\mu}m$ was highest in scraping method (39.6% vs. enzymatical method: 30.1%, p<0.05; mincing method: 30.9%, p=0.11719, NS). Rate of follicles in $91{\sim}130$ ${\mu}m$ was significantly (p<0.05) lower in scraping method (52.7%) than in enzymatical or mincing method (66.3% or 64.5%). Rate of follicles in ${\geq}$131 ${\mu}m$ was highest in scraping method (8.3% vs. enzymatical or scraping method: 3.6%, p<0.05 or 4.6%, p=0.19053, NS). Conclusions: This study suggests that scraping method is simple and useful for isolation of preantral follicles, because this method reduced handling time and recovered enough follicles. The recovered rate of isolated follicles in diameter of 91 ~ 130 ${\mu}m$ was highest in all methods.

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Reactive Oxygen Species Mediates Lysophosphatidic Acid-induced Migration of SKOV-3 Ovarian Cancer Cells (SKOV-3 난소암 세포주에서 lysophosphatidic acid 유도 세포의 이동에 있어 활성산소의 역할)

  • Kim, Eun Kyoung;Lee, Hye Sun;Ha, Hong Koo;Yun, Sung Ji;Ha, Jung Min;Kim, Young Whan;Jin, In Hye;Shin, Hwa Kyoung;Bae, Sun Sik
    • Journal of Life Science
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    • v.22 no.12
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    • pp.1621-1627
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    • 2012
  • Cell motility plays an essential role in many physiological responses, such as development, immune reaction, and angiogenesis. In the present study, we showed that lysophosphatidic acid (LPA) modulates cancer cell migration by regulation of generation of reactive oxygen species (ROS). Stimulation of SKOV-3 ovarian cancer cells with LPA strongly promoted migration. but this migration was completely blocked by pharmacological inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Inhibition of the ERK pathway had no effect on migration. Stimulation of SKOV-3 ovarian cancer cells with LPA significantly induced the generation of ROS in a time-dependent manner. LPA-induced generation of ROS was significantly blocked by pharmacological inhibition of PI3K or Akt, but inhibition of the ERK signaling pathway had little effect. LPA-induced generation of ROS was blocked by pretreatment of SKOV-3 ovarian cancer cells with an NADPH oxidase inhibitor, whereas inhibition of xanthine oxidase, cyclooxygenase, or mitochondrial respiratory chain complex I had no effect. Scavenging of ROS by N-acetylcysteine completely blocked LPA-induced migration of SKOV-3 ovarian cancer cells. Inhibition of NADPH oxidase blocked LPA-induced migration whereas inhibition of xanthine oxidase, cyclooxygenase, or mitochondrial respiratory chain complex I did not affect LPA-induced migration of SKOV-3 ovarian cancer cells. Given these results, we suggest that LPA induces ROS generation through the PI3K/Akt/NADPH oxidase signaling axis, thereby regulating cancer cell migration.

Spontaneous Parthenogenesis of Porcine Oocyte Induced by Prolonged Culture in Various Media (다양한 배지에서 장시간 배양에 의한 돼지 난자의 단위발생 유도)

  • J. M. Koo;Y. J. Ryu;Lee, E. G.;Kim, D. Y.;Kim, S. W.;S. K. Kang;Lee, B. C.;W. S. Hwang
    • Journal of Embryo Transfer
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    • v.18 no.1
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    • pp.69-73
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    • 2003
  • This study was undertaken to investigate the effect of three different porcine IVM media, TCM-199, mSOF and NCSU-23 on early development of porcine spontaneous parthenogenotes. Spontaneous parthenogenotes were induced by a prolonged culture of porcine oocytes in each medium. In Experiment 1, oocytes derived from gilts were matured in three IVM media and maturation of oocytes was evaluated by the status of chromatin configuration. Oocytes matured in mSOF, NCSU-23 and TCM-199 showed no significant difference (P>0.05) in maturation. Maturation rates at 48h after IVM were 83.1$\pm$2% (mSOF), 78.0$\pm$3% (NCSU-23) and 83.5$\pm$2% (mSOF), 78.0$\pm$3% (NCSU-23) and 83.5$\pm$2% (TCM-199). In Experiment 2, pronucleus formation and development to 6~8 cell stage of pig oocytes activated spontaneously. Pronucleus formation, cleavage rate and development to 6~8 cell embryos of porcine spontaneous parthenogenotes were assessed at 55~58 h, 96 h and 168h after IVM, respectively. Pronucleus formation (5.4$\pm$2% and 3.7 $\pm$ 1% vs 1.7 $\pm$ 3%) and development to the 6$\pm$8 cell (3.2$\pm$3% and 4.0$\pm$1% vs 1.4$\pm$3%) was significantly (P<0.05) higher in mSOF or NCSU-23 than TCM-199. In conclusion, the present study showed that oocytes matured in mSOF and NCSU-23 were spontaneously activated with higher frequency.

Antibacterial Effect of Hiscus cannabinus L. Methanol Extract against Pathogenic Bacteria in Domestic Animals (Kenaf methanol 추출물의 가축 주요 병원성 균에 대한 항균효과)

  • Lim, Jeong-Ju;Kim, Dong-Hyeok;Lee, Jin-Ju;Kim, Dae-Geun;Lee, Hu-Jang;Min, Won-Gi;Park, Dong-Jin;Huh, Moo-Ryong;Chang, Hong-Hee;Rhee, Man-Hee;Kim, Suk
    • Journal of agriculture & life science
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    • v.45 no.2
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    • pp.43-50
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    • 2011
  • Hibiscus cannabinus L. is a plant in the Malvaceae family, that was seeded at June 1st in 2010 and harvested at November 18th. The present study was designated to investigate the safety for host cells, antibacterial effects of Hibiscus cannabinus L. of flower (HCME-F) or leaf (HMEF-L) methanol extract for typical Gram's positive bacteria (St. aureus and Str. epidermidis) or Gram's negative bacteria (S. typhimurium and E. coli). In treatment of different concentrations of HCME-F or HMEF-L (1, 50 and $100{\mu}g/ml$), cytotoxic effects were not shown to RAW 264.7 cells until 24 h incubation. In determination of antibacterial activity of HCME-F or HMEF-L, the antibacterial activities for St. aureus and Str. epidermidis were markedly increased compared to that of untreated control group, but antibacterial activity of HCME-F or HMEF-L for S. typhimurium and E. coli were not changed. Taken together, we demonstrated that methanol extract of HCME-F or HMEF-L showed the safety for RAW 264.7 cells and antibacterial activities for Gram's positive pathogenic bacteria St. aureus and Str. epidermidis. These findings suggest that a methanol extract of Kenaf flower or leaf may be useful alternatives of conventional chemotherapies for dermatitis and mastitis causing Gram's positive pathogens such as Stapylococcus spp. and Streptococcus spp. in domestic animals and humans.

Comparison of antioxidant capacity of protein hydrolysates from 4 different edible insects (식용곤충별 단백가수분해물의 항산화 활성 비교)

  • Jang, Hyun-Young;Park, Chae-Eun;Lee, Syng-Ook
    • Korean Journal of Food Science and Technology
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    • v.51 no.5
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    • pp.480-485
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    • 2019
  • The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.

Gene Expression of Detoxification Enzymes in Tenebrio molitor after Fungicide Captan Exposure (살진균제인 캡탄 처리 후 갈색거저리의 해독효소 유전자 발현)

  • Jang, Ho am;Baek, Hyoung-Seon;Kim, Bo Bae;Kojour, Maryam Ali Mohammadie;Patnaik, Bharat Bhusan;Jo, Yong Hun;Han, Yeon Soo
    • Korean journal of applied entomology
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    • v.61 no.1
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    • pp.155-163
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    • 2022
  • The application of fungicides is indispensable to global food security, and their use has increased in recent times. Fungicides, directly or indirectly, have impacted insects, leading to genetic and molecular-level changes. Various detoxification mechanisms allow insects to eliminate reactive oxygen species (ROS) toxicity induced by agrochemicals including fungicides. In the present study, we analyzed the mRNA expression levels of detoxifying enzymes in Tenebrio molitor larvae following exposure to non-lethal doses (0.2, 2, and 20 ㎍/µL) of a fungicide captan. Transcripts of peroxidases (POXs), catalases (CATs), superoxide dismutases (SODs), and glutathione-s-transferases (GSTs) were screened from the T. molitor transcriptome database. RT-qPCR analysis showed that TmPOX5 mRNA increased significantly 24 h post-captan exposure. A similar increase was noticed for TmSOD4 mRNA 3 h post-captan exposure. Moreover, the expression of TmCAT2 mRNA increased significantly 24 h post-treatment with 2 ㎍/µL captan. TmGST1 and TmGST3 mRNA expression also increased noticeably after captan exposure. Taken together, these results suggest that TmPOX5 and TmSOD4 mRNA can be used as biomarkers or xenobiotics sensors for captan exposure in T. molitor, while other detoxifying enzymes showed differential expression.