• Title/Summary/Keyword: science-related activity

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Comparison of Muscle Activity and Input Performance of Operators Using a Computer Mouse and a Trackball

  • Yoo, Hwan-Suk;Yi, Chung-Hwi;Kwon, Ho-Yun;Jeon, Hye-Seon;Yoo, Won-Gyu
    • Physical Therapy Korea
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    • v.16 no.4
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    • pp.37-43
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    • 2009
  • This study compared the electromyographic activities and input performance of computer operators using a computer mouse and a trackball. Muscle activities were assessed at the upper trapezius (UT), middle deltoid (MD), extensor digitorum (ED), and first dorsal interosseous muscle (FDI). Twenty-six healthy subjects were recruited, and the test order was selected randomly for each subject. The task set was to click moving targets on a Windows program. The EMG amplitude was normalized using the percentage of reference voluntary contraction for UT and MD and the percentage of maximal voluntary contraction for ED and FDI. To analyze the differences in EMG activity, a paired t-test was used. UT muscle activities were significantly greater when the computer mouse was used (p<.05). FDI muscle activities were significantly greater when the trackball was used (p<.05). Using a trackball can reduce the load on the UT during computer work and help to prevent and manage work-related musculoskeletal disorders.

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Structural and Functional Importance of Two Glutamate Residues, Glu47 and Glu146, Conserved in N-Carbamyl D-Amino Acid Amodohydrolases

  • Oh, Ki-Hoon;Kim, Geun-Joong;Park, Joo-Ho;Kim, Hak-Sung
    • Journal of Microbiology and Biotechnology
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    • v.11 no.1
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    • pp.29-34
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    • 2001
  • The mutant enzymes of N-carbamyl-D-amino aicd amidohydrolase (N-carbamylase) from Agrobacterium radiobacter NRRL B11291, showing a negligible activity, were selected from the library generated by random mutagenesis. From the sequence analysis, these mutants were found to contain the amino acids substitutions at Cys172, Glu47, and Glu146. Previously, Cys172 was reported to be necessary for the enzyme catalysis. The chemical modification of the N-carbamylase by carboxyl group specific chemical reagent, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide(EDC), resulted in a loss of activity. The replacement of glutamic acids with glutamines by site-directed mutagenesis led to aggregation of the enzymes. Mutant enzymes fused with maltose binding protein (MBP) were expressed in soluble form, but were inactive. These results indicate that two glutamic acid residues play an important role in structure and function of the N-carbamylase. Multiple sequence alignment of the related enzymes revealed that Glu47 and Glu146 are rigidly conserved, which suggests that tese residues are crucial for the structure and function of the functionally related C-N hydrolases.

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Antioxidant Activities in Germinated and Non-germinated Seeds of Korean Weedy Rice

  • Cho, Ei Ei;Baek, Jung-Sun;Chung, Nam-Jin
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.63 no.3
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    • pp.219-228
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    • 2018
  • Weedy rice (Oryza sativa) is a semi-wild rice grown in paddy fields and is more adapted to the environment than cultivated rice. Therefore, it is expected that the seeds of weedy rice might contain some chemicals related to its environmental adaptation, such as antioxidants, which may be useful for nutritional and medicinal purposes. This study was carried out to investigate the antioxidant activities of weedy rice compared to a Korean-bred rice cultivar, Sindongjin (SDJ), and to screen lines that show higher antioxidant activity in 199 accessions of weedy rice germplasm collected in Korea. DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity ranged from 31.0 to 91.7%, with an average of 82.5%, and 19 accessions that showed more than 91% antioxidant activity were selected. The 19 accessions were re-screened against non-germinated brown rice (BR) and germinated brown rice (GBR) using four assays, total phenol determination, DPPH radical scavenging, ABTS radical scavenging, and reducing power activities. The results showed that accession 'WD3' had the highest antioxidant capacity in both BR and GBR, suggesting that WD3 is a promising potential source of antioxidants and could be developed as a potentially functional substance material.

The NILs from an interspecific cross show enhanced plant height and antioxidant activity

  • Jeon, Yun-A;Kim, Dong-Min;Ahn, Sang-Nag
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.118-118
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    • 2017
  • A high-resolution physical map targeting a cluster of yield-related QTLs on the long arm of rice chromosome 9 was constructed across a 35.5kb region containing the six predicted genes including the probable ascorbate peroxidase (OsApx). The $BC_3F_6$ near isogenic lines (NILs) were derived from a cross between the Oryza sativa Hwaseong and O. rufipogon. The plant height and length of internodes were compared between Hwaseong and NILs. There were significant differences in plant height between Hwaseong and NILs. The NILs internodes were longer than Hwaseong, showing dramatic elongation in the first and fourth internodes; thereby, leading to increased plant height. The antioxidant activity of Hwaseong and NILs was also analyzed by 3,3-diaminobenzidine (DAB) staining and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. In order to understand whether or not OsApx gene is important in scavenging $H_2O_2$ in rice, DAB staining was used. Intense dark-brown coloration was observed in Hwaseong than NILs. In addition, DPPH scavenging ability of Hwaseong showed lower value than NILs. These results indicated that the internode elongation and antioxidant activity might possibly be controlled by OsApx. To know the causative relationship of the gene and phenotype, we will further analyze the gene expression and use it for functional studies by complementation transgenic approach.

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An Exploration of the Factors Related with Preference for and Participation in Science-related Activities of Elementary School Student (과학 관련 활동에 대한 초등학생의 선호 및 참여와 관련된 요인 탐색)

  • Yang, Chanho;Jo, Junmo;Kim, Chan-Jong;Choe, Seung-Urn;Kim, Heui-Baik;Yoo, Junehee;Yi, Kyung-Woo;Kye, Young Hee;Noh, Taehee
    • Journal of Korean Elementary Science Education
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    • v.33 no.3
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    • pp.427-438
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    • 2014
  • In this study, we explored the factors related with preference for and participation in science-related activities of elementary school students. We developed a questionnaire to measure the characteristics of students such as motivation toward science learning, science aspiration, family science orientation, parental educational level and occupation, and the degrees of preference and participation of science-related activities. The questionnaire was administered to about 400 fourth graders in Seoul. The results revealed that the students with higher motivation toward science learning and/or science aspiration preferred and participated more in most activities. It was also found that parental educational level and occupation did not make an appreciable difference in preference and participation. The students who perceived their parents to be science-oriented, however, preferred and participated more in most activities. These results may offer practical implications for effective uses of both school and out-of-school science activities in elementary science education.

Purification of Vasopressin-related Peptide, [Arg8]-vasotocin, from the Brain of Conger Eel (Conger myriaster) (붕장어 (Conger myriaster)의 뇌로부터 Vasopressin-related Peptide, [Arg8]-vasotocin의 정제)

  • Go Hye-Jin;KIM Chan-Hee;KIM Eun Jung;KIM In Hye;PARK Hee Yeon;YOON Ho Dong;HONG Yong-Ki;PARK Nam Gyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.38 no.1
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    • pp.6-11
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    • 2005
  • Vasopressin (VP)-related peptide was purified from the brain extract of conger eel (Conger myriaster) by reverse-phase, ion-exchange high performance liquid chromatography (HPLC). This peptide with a molecular weight of 1,051.2 Da was determined as $H-Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Arg-Gly-NH_2$, whose Cys residues made an intramolecular disulfide bridge by the automated amino acid sequence analysis, MALDI- TOF mass spectrometry. It's sequence was confirmed by identity of the elution position with the synthetic peptide in HPLC system. As a result of homology investigation, the primary structure of this peptide was the same as that of VP-superfamily member, $[Arg^8]-vasotocin$. The synthetic peptide showed a contractile activity at a minimal effective concentration of $10^{-10}\;M$ on the intestinal smooth muscle of goldfish.

The Effect of Meliae toosendan fructus Ethanol Extract on Blood Glucose, Lipid metabolism, Carbohydrate Methabolism Related Enzyme Activities and Antioxidative Effect in Streptozotocin-Induced Diabetic Rats (천련자 에탄올 추출물이 Streptozotocin으로 유발된 당뇨 흰쥐에 대한 혈당, 지질대사, 당대사 효소 활성과 항산화 작용에 미치는 영향)

  • Kim, Ok-Kyung;Leem, Hee-Jin;Je, Jung-Min;Lee, Gyung-Mi
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.2
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    • pp.277-284
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    • 2014
  • The ethanol extraction yield of Meliae toosendan fructus(MT) was about 24.5% by extract apparatus. This study was done to investigate the carbohydrate metabolism related enzyme activities and antioxidative effects of MT in streptozotocin (STZ)-induced diabetic rats. The contents of serum glucose, triglyceride (TG) were significantly decreaed in MT treated group compared to the those of STZ-control group, also content of Total cholesterol was decreased. High density lipoprotein (HDL)-cholesterol was increased in MT treated group. The activity of glucose-6-pase(G-6-Pase) was significantly decreased in MT treated group. Also the activities of glucose-6-phosphate dehydrogenase(G-6-PDH) and glucokinase(Gk) were increaed in MT treated group. The content of hepatic glycogen was significantly increaed in MT treated group, in addition, content of malondialdehyde(MDA) was significanly decreased in MT treated group. Also, content of glutathione(GSH)was dereased in MT treated froup. whereas, activity of catalase(CAT) was significantly increaed in MT treated group compared to the those of STZ-control group. activity of glutathione peroxidase(GSH-Px) was inecreaed. In conclusion, these results indicated that ethanol extract of MT would have carbohydrate metabolism antioxidative effects in STZ-induced diabetic rats.

Beauty Food Activities of Isolated Phenolic Compounds from Ulmus pumila (유근피(Ulmus pumila)로부터 분리한 페놀성물질의 미용식품활성)

  • Kim, Kyung-Bum;Jo, Bun-Sung;Lee, Ju-Yeong;Park, Ki-Tae;An, Bong-Jeun;Lee, Sun-Ho;Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • v.55 no.4
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    • pp.207-215
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    • 2012
  • Phenolic compounds of $17.9{\pm}1.0mg/g$ were extracted from Ulmus pumila with 70% ethanol. The elastase inhibitory activity related with forming wrinkle was shown an excellent wrinkle improvement effect in 70% ethanol extracts as 55.5-69.5% at phenolic concentration of $50-200{\mu}g/mL$. The tyrosinase inhibitory activity related with skin-whitening was 24% in 70% ethanol extracts at phenolic concentration of $200{\mu}g/mL$. The astringent activity of 70% ethanol extracts was shown activity of 71% at phenolic concentration of $200{\mu}g/mL$ therefore it is judged that there is a high effect on pores reduction of the skin. The hyaluronidase inhibitory activity of U. pumila extracts was confirmed anti-inflammation effect of 80% at phenolic concentration of $50{\mu}g/mL$. Antimicrobial activity of U. pumila water extracts was shown each 8.7, 10.0, 11.1 and 11.8 mm clear zones on Propionebacterium acnes at phenolic concentration of $50-200{\mu}g/mL$. The stability of the multi-functional cosmetic (lotion) added U. pumila extracts was very stable for 28 days without changing of pH and viscosity also it's stable on temperature and sun lights. As the concentration of extracts was increased, the color of lotion was getting dark, but the sensory evaluation was high at score of 8.5.

Antioxidative Activity and Varietal Difference of Cyanidin 3-glucoside and Peonidin 3-glucoside Contents in Pigmented Rice

  • Ryu, Su-Noh;Han, Sang-Jun;Park, Sun-Zik;Kim, Hong-Yeol
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.45 no.4
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    • pp.257-260
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    • 2000
  • The content of anthocyanin, cyanidin 3-glucoside (C3G) and the peonidin 3-glucoside (P3G) from 591 rice cultivars and the antioxidative activities of MeOH extract from 8 rice cultivars were evaluated. Among them, C3G content of pigmented rice were ranged from 0 to 451.9mg in 100 g brown rice, while the P3G contents were in the range from 0 to 42.7mg in 100g brown rice. There was no correlation between C3G and P3G content. Total anthocyanin content ranged from 0 to 475.1mg in 100g brown rice. The antioxidative activity, the scavenging activity on DPPH (2,2-diphenyl-picryl-hydrazyl) radical of MeOH extracts from rice grain, were different according to cultivars. The activity of blockish purple pericarp rice cultivars was twice stronger than that of white pericarp cultivar. Especially, the antioxidative activity of Heugjinjubyeo was four times stronger than that of white pericarp cultivar. The scavenging effect on DPPH radical in rice extracts was related to the total anthocyanin contents of the extracts.

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Variation of Muscle Activity and Balance of the Lower Extremity by Deformed in Shoe Out-soles during One-leg Stance

  • Won-Jun Choi;Min-Je Jo;Doochul shin
    • Physical Therapy Rehabilitation Science
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    • v.12 no.2
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    • pp.161-166
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    • 2023
  • Objective: The purpose of the study was to investigate the effect of shoe sole deformation on the muscle activity and balance of the lower extremities when standing on one foot. Design: Crossed-control group study Methods: A total of 18 healthy adults participated in this study. 9 participants with normal shoe and 9 participants with deformed in shoe out-soles (wear shoes) were included. Muscle activity of the tibialis anterior, fibularis longus and gluteus medius during one leg standing was measured using a electromyography. A balance board was used to evaluate balance ability when standing on one leg. The balance ability when standing on one leg was measured by the sway speed and distance of the center of gravity. Results: Muscle activity of the tibialis anterior, fibularis longus and gluteus medius was no significant difference between groups (P > 0.05). Balance ability when standing on one leg was significantly different from the group wearing normal shoes in all variables related to the sway distance and sway speed of the center of gravity. Conclusions: Through this study, the wear of the outer sole of the shoe indirectly confirmed the effect on the wearer's lower extremity muscle activity and balance ability when standing on one foot. These results of this study are expected to be used as basic data for future studies on shoe wear, lower extremity muscle activity and balance ability.