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Synthesis of Dihydroxylated Chalcone Derivatives with Diverse Substitution Patterns and Their Radical Scavenging Ability toward DPPH Free Radicals

  • Kim, Beom-Tae;O, Kwang-Joong;Chun, Jae-Chul;Hwang, Ki-Jun
    • Bulletin of the Korean Chemical Society
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    • v.29 no.6
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    • pp.1125-1130
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    • 2008
  • A series of dihydroxylated chalcone derivatives with diverse substitution patterns on a phenyl ring B and the para-substituents on a phenyl ring A were prepared, and their radical scavenging activities were evaluated by simple DPPH test to determine quantitative structure-activity relationship in these series of compounds. The chalcone compounds with the ortho- (i.e. 2',3'- and 3',4'-) and para- (i.e. 2,5'-) substitution patterns show an excellent antioxidant activities (80-90% of control at the concentration of 50 $\mu$M) which are comparable to those of ascorbic acid and $\alpha$ -tocopherol as positive reference materials. On the contrary, the compounds with meta- (i.e. 2',4'-, 3',5'-) substitution pattern demonstrate very dramatic decrease in activities which are around 25% of the control even at the concentration of 200 $\mu$ M (IC50 > 200 $\mu$ M). These dramatic differences could be interpreted in terms of the ease formation of fairly stable semiquinone radicals from the ortho- and parasubstituted chalcone molecules through facilitating electron delocalization. Our results indicate that the substitution patterns of two hydroxyl groups on ring B are very important structural factors for their radical scavenging activity enhancement. Meanwhile, the substituents at para-position of the phenyl ring A of chalcones have no influence on the activity.

A Discussion on the Definitions of Seismic Coefficient for Gravity Quay Wall in Korea (국내 중력식 안벽의 수평지진계수 산정 방법에 대한 고찰)

  • Lee, Moon Gyo;Jo, Seong Bae;Cho, Hyung Ik;Park, Heon Joon;Kim, Dong Soo
    • Journal of the Earthquake Engineering Society of Korea
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    • v.21 no.2
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    • pp.77-85
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    • 2017
  • Pseudo-static approach has been conventionally applied for the design of gravity quay walls. In this method, the decision to select an appropriate seismic coefficient ($k_h$) is an important one, since $k_h$ is a key variable for computing an equivalent pseudo-static inertia force. Nonetheless, there is no unified standard for defining $k_h$. Likewise, port structure designers in Korea have a difficulty in choosing an appropriate $k_h$ definition, as there are conflicts in how $k_h$ is defined between the existing seismic code of port structures and the proposed new one. In this research, various seismic design codes for port structures were analyzed to compare the definitions of the seismic coefficient. The results were used for the proposing a unified seismic coefficient definition. Further, two dynamic centrifuge tests were performed with different wall heights (5 m, 15 m) to clarify the reference point of peak acceleration used in determination of $k_h$ according to the wall height. Results from dynamic centrifuge experiments showed that correction factors for the peak ground acceleration considering both the wall height and allowable displacement are needed to calculate $k_h$.

Improved Performance of Microstrip Antenna using the Compact Photonic Band-gap Structures (소형 포토닉 밴드갭 구조를 이용한 마이크로스트립 안테나의 성능 향상)

  • Kim Young-Do;Lee Hong-Min
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.5 s.347
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    • pp.147-155
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    • 2006
  • In this paper, we propose a new Mushroom-like PBG concepts for designing with forbidden frequency band-gap at low frequency. These design rules are based on enhancing the capacitance per unit area using modified top-patch of mushroom PBG with no increase on the overall thickness of the substrate board. Also, in this paper, a new approach to suppress the surface wave from antenna is proposed by embedding compact mushroom PBG in the substrate. Comparisons between the results from a conventional patch antenna to a patch antenna on a PBG substrate show that the reduction in the surface wave level is remarkable. This can be observed in the radiation pattern and the maximum gain. The maximum gain for reference patch antenna is $6.43dB{\imath}$ at 5.37 GHz, while the maximum gain for the patch antenna with normal mushroom and vane mushroom PBG is $7.24dB{\imath}\;and\;7.53dB{\imath}$at 5.14 GHz. The back radiation is also considerably reduced; this will lead, of course, to an increase in the antenna efficiency.

Expression of β-tubulin III and Survivin in Advance Stage Breast Cancer Correlates with Chemotheraputic Effects of Docetaxel

  • Yuan, Shao-Fei;Zhu, Lin-Jia;Zheng, Wei-E;Chen, Hua;Wu, Li-Li;Zhang, Wu;Sun, Hong-Yu;Chen, Wen-Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.1
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    • pp.361-365
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    • 2012
  • Aims: To investigate the relationship between the expression of ${\beta}$-tubulin III and survivin in advanced breast cancers and chemotherapeutic effects of docetaxel. Methods: Clinical pathological data of 74 patients with advanced breast cancer were retrospectively analyzed after docetaxel chemotherapy. Expression of ${\beta}$-tubulin III and survivin was assessed by immunohistochemistry and analyzed with reference to therapeutical and adverse effects of docetaxel. Results: The positive expression rate of ${\beta}$-tubulin III was 38.1% (32/84), while that of survivin was 76.2% (64/84). The effective rate (complete response + partial response) was 52.4%. That for patients with the positive expression of ${\beta}$-tubulin III or/and survivin was significantly lower than for those with negative expression (P<0.05). There were significant differences in the non-progression of median diseases, 1-year and 2-year survival rates of between the patients with positive and negative expression (P<0.05). The main side effects were myelosuppression, alimentary canal response and alopecie, no differences being observed between groups. Conclusions: The combined detection of ${\beta}$-tubulin III and survivin is a predictive index for chemotherapy effects of docetaxel in metastatic breast cancer.

Comparison of Concurrent Chemoradiotherapy Followed by Adjuvant Chemotherapy Versus Concurrent Chemoradiotherapy Alone in Locoregionally Advanced Nasopharyngeal Carcinoma: a Meta-analysis of 793 Patients from 5 Randomized Controlled Trials

  • Liang, Zhong-Guo;Zhu, Xiao-Dong;Zhou, Zhi-Rui;Qu, Song;Du, You-Qin;Jiang, Yan-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.11
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    • pp.5747-5752
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    • 2012
  • Purpose: The main objective of the present study was to evaluate the efficacy and toxicity of concurrent chemoradiotherapy followed by adjuvant chemotherapy compared with concurrent chemoradiotherapy alone in the treatment of locoregionally advanced nasopharyngeal carcinoma. Methods: The search strategy included Pubmed, Embase, the Cochrane Library, China National Knowledge Internet Web, Chinese Biomedical Database and Wanfang Database. We also searched reference lists of articles and the volumes of abstracts of scientific meetings. Randomized controlled trials (RCTs) that compared concurrent chemoradiotherapy followed by adjuvant chemotherapy with concurrent chemoradiotherapy alone in locoregionally advanced nasopharyngeal carcinoma were included. Meta-analysis was performed with RevMan 5.1.0. The Grading of Recommendations Assessment, Development, and Evaluation system (GRADE) was used to rate the level of evidence. Results: Five studies were included. Risk ratios of 1.02 (95%CI 0.89-1.15), 0.93 (95%CI 0.72-1.21), 1.07 (95%CI 0.87-1.32), 0.95 (95%CI 0.80-1.13) were observed for 3 years overall survival, 5 years failure-free survival, 5 years locoregional failure-free survival and 5 years distant metastasis failure-free survival. There were no treatment-related deaths in both groups of five studies. Hematologic and gastrointestinal toxicity were the most significant for patients during adjuvant chemotherapy. The level of evidence was low. Conclusion: Compared with concurrent chemoradiotherapy alone, concurrent chemotherapy followed by adjuvant chemotherapy did not improve prognosis. More toxicity was found during adjuvant chemotherapy.

A Study on the Image of Adult Foundations (남.녀 파운데이션 이미지 연구)

  • Lee, Hyo-Jin;Yang, A-Rang
    • The Research Journal of the Costume Culture
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    • v.19 no.2
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    • pp.255-268
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    • 2011
  • This study carefully explored today's preferable beauty images, analyzed Korean adult purchasing trends of functional underwear and market analysis of the most popular items and their designs. Information and methods are based largely on reference book material as well as analysis of real domestic data. The paper's research timeline simply spans the last three years, as in accordance with project parameters. Helping improve body shape, foundation literally means 'substructur' and 'base'. The formativeness in these adult foundations typically has three main category classifications. First, natural modern image. This is where we find natural beauty including that which embodies a cool modern sense. Here, you can often see such patterns as either stripes and dots, or simply no patterns at all. Colors are green, red-brown, incarnadine, or khaki from a natural or basic human body color. Its products are marketed as both solid and durable eco-friendly materials, and lace-seethrough. Fashion's natural modern image is undoubtedly the most popular style purchase choice among both genders. Second, sweet romantic image. This mainly consists of two concepts : a sweet and romantic theme, and visual appeal. Patterns include flowers, lips, heart, stars, candies and various other appealing characters. Its main colors are pink, yellow, red, purple, and violet. Products are decorated with laces, frills and ribbons. Since only men's semi-girdles carry such designs, this fashion foundation is largely a women's world. While men show an obvious interest in foundation, they still mostly prefer the choice of natural modern images. Third, mystic sexy image. This is defined as all feminine images of mysterious and classic sexual beauty. Patterns are variously expressed as paisley, flowers, and geometric. Colors are largely purple, blue-green, royal-blue, cobalt, and black. Products are commonly decorated with beading, spangles, hot-fixes and so on. While this image can be found in all kinds of women's foundations, it typically appears only in men's corsets and girdles.

Effects of Dietary and Physical Activity Interventions on Metabolic Syndrome: A Meta-analysis (대사증후군에 대한 식이와 운동 효과에 대한 메타분석)

  • Lee, Guna;Choi, Hye-Young;Yang, Sook-Ja
    • Journal of Korean Academy of Nursing
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    • v.45 no.4
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    • pp.483-494
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    • 2015
  • Purpose: This study identified effects of dietary and physical activity interventions including dietary interventions or physical activity interventions alone or combined dietary-physical activity interventions to improve symptoms in metabolic syndrome including abdominal obesity, high triglycerides, low high density lipoprotein cholesterol, elevated blood pressure, and elevated fasting glucose through meta-analysis. Methods: Articles on metabolic syndrome X published from 1988 to 2013 were searched through electronic databases, Google Scholar, and reference reviews. Methodological quality was assessed by the checklist, SIGN (Scottish Intercollegiate Guidelines Network). Results: In the meta-analysis, there were 9 articles reporting 13 interventions with 736 participants. Using random effect models, the dietary and/or physical activity interventions showed a lower mean difference in waist circumference ( - 1.30 cm, 95% CI: - 2.44~ - 0.15, p=.027). The combined dietary-physical activity interventions showed a lower mean difference in waist circumference ( - 2.77 cm, 95% CI: - 4.77~ - 0.76, p=.007) and systolic blood pressure ( - 5.44 mmHg, 95% CI: - 10.76~ - 0.12, p=.044). Additionally, interventions of over 24 weeks yielded a lower mean difference in waist circumference ( - 2.78 cm, 95% CI: - 4.69~ - 0.87, p=.004) and diastolic blood pressure ( - 1.93 mmHg, 95% CI: - 3.63~ - 0.22, p=.026). Conclusion: The findings indicate that dietary and/or physical activity interventions for metabolic syndrome reduce central obesity with no adverse effects. This finding provides objective evidences for dietary and physical activity management on metabolic syndrome as an efficient intervention.

Magnesium Status in Children with Attention-Deficit/Hyperactivity Disorder and/or Autism Spectrum Disorder

  • Skalny, Anatoly V.;Mazaletskaya, Anna L.;Ajsuvakova, Olga P.;Bjorklund, Geir;Skalnaya, Margarita G.;Chernova, Lyubov N.;Skalny, Andrey A.;Tinkov, Alexey A.
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.31 no.1
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    • pp.41-45
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    • 2020
  • Objective: The objective of this study was to assess serum, hair, and urinary magnesium (Mg) levels in children with attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and both ASD and ADHD to reveal potential interactive effects. Methods: A total of 148 boys aged 4-9 years old were enrolled in this study, including 44 children with ADHD, 40 pediatric patients with ASD, 32 patients with both ADHD and ASD, as well as 32 healthy neurotypical children. Hair, serum, and urinary Mg levels were assessed using inductively-coupled plasma mass spectrometry (ICP-MS). Laboratory quality control was performed using certified reference materials of human hair, plasma, and urine. Results: No significant group difference in serum Mg levels was observed. Mg content in hair was found to be reduced in children with ADHD and ADHD+ASD compared to that in healthy controls by 11% and 15%, respectively. Urinary Mg levels in children with ADHD+ASD exceeded the control, ADHD, and ASD values by 51, 76, and 65%, respectively. Factorial analysis revealed significant contribution of ADHD to hair and urinary Mg levels. Multiple regression analysis demonstrated that hair and urinary Mg levels were considered as significant predictors of neurodevelopmental disorder complexity. Conclusion: We propose that impaired Mg status may provide a link between ADHD and ASD.

Parametric Analysis of the Solar Radiation Pressure Model for Precision GPS Orbit Determination

  • Bae, Tae-Suk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.1
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    • pp.55-62
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    • 2017
  • The SRP (Solar Radiation Pressure) model has always been an issue in the dynamic GPS (Global Positioning System) orbit determination. The widely used CODE (Center for Orbit Determination in Europe) model and its variants have nine parameters to estimate the solar radiation pressure from the Sun and to absorb the remaining forces. However, these parameters show a very high correlation with each other and, therefore, only several of them are estimated at most of the IGS (International GNSS Service) analysis centers. In this study, we attempted to numerically verify the correlation between the parameters. For this purpose, a bi-directional, multi-step numerical integrator was developed. The correlation between the SRP parameters was analyzed in terms of post-fit residuals of the orbit. The integrated orbit was fitted to the IGS final orbit as external observations. On top of the parametric analysis of the SRP parameters, we also verified the capabilities of orbit prediction at later time epochs. As a secondary criterion for orbit quality, the positional discontinuity of the daily arcs was also analyzed. The resulting post-fit RMSE (Root-Mean-Squared Error) shows a level of 4.8 mm on average and there is no significant difference between block types. Since the once-per-revolution parameters in the Y-axis are highly correlated with those in the B-axis, the periodic terms in the D- and Y-axis are constrained to zero in order to resolve the correlations. The 6-hr predicted orbit based on the previous day yields about 3 cm or less compared to the IGS final orbit for a week, and reaches up to 6 cm for 24 hours (except for one day). The mean positional discontinuity at the boundary of two 1-day arcs is on the level of 1.4 cm for all non-eclipsing satellites. The developed orbit integrator shows a high performance in statistics of RMSE and positional discontinuity, as well as the separations of the dynamic parameters. In further research, additional verification of the reference frame for the estimated orbit using SLR is necessary to confirm the consistency of the orbit frames.

Effects of insect-resistant genetically modified rice (Bt-9) cultivation on non-target insect diversity

  • Oh, Sung-Dug;Lim, Myung-Ho;Lee, Bumkyu;Yun, Doh-Won;Sohn, Soo-In;Chang, Ancheol;Park, Soon Ki;Suh, Sang Jae
    • Korean Journal of Agricultural Science
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    • v.45 no.1
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    • pp.28-37
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    • 2018
  • This study was done to develop environmental risk assessments and a biosafety guide for insect-resistant genetically modified rice at a LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-9) resistant to Cnaphalocrocis medinalis and on non-GM rices (Dongjin and Ilmi) were investigated. The Bt-9 event was therefore evaluated under field conditions to detect possible impacts on the above ground insects and spiders. The study compared transgenic rice and two non-GM reference rices, Ilmi and Dongjin, at Gunwi in Southern Korea in 2016. Each rice was grown on three $18m^2$ plots with a randomized block design. A total of 4,243 individuals from 43 families and 9 orders were collected from the LMO isolation field. In the three types of rice fields, a total of 1,467 individuals from the insect-resistant genetically modified rice (Bt-9), 1,423 individuals from the Ilmi, and 1,353 individuals from the Dongjin were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies and other insects on the insect-resistant genetically modified rice (Bt-9) and non-GM rices. These results provide the diversity and population density of non-target insects for an environment risk assessment survey on insect-resistant genetically modified rice and could be used as a guideline to make a biosafety assessment method for genetically modified crops.