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Screening of Extraction Solvent Condition of Fermented Rhus verniciflua Stem Bark by Antioxidant Activities (항산화활성 비교를 통한 발효 칠피의 추출용매 조건 탐색)

  • Kim, Myeong-Ok;Kim, Ju-Sung;Sa, Yeo-Jin;Jeong, Hyun-Ju;Chun, Wan-Joo;Kwon, Yong-Soo;Kim, Tae-Young;Choi, Han-Seok;Yu, Chang-Yeon;Kim, Myong-Jo
    • Korean Journal of Medicinal Crop Science
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    • v.18 no.4
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    • pp.217-223
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    • 2010
  • In this study, we investigated antioxidant capacity and determined the phenolic and flavonoid contents using each of various solvent conditions from fermented Rhus verniciflua stem bark (F-RVS). Each extracts displayed markedly similar content of extraction yield. However, M80 extract showed a significantly higher antioxidant activity in comparison to other extract investigated. M80 exhibited strong DPPH radical scavenging activity with $RC_{50}$ value of $10.5{\pm}1.4{\mu}g/m{\ell}$, reducing power value 1.04 Abs (concentration of 1 mg/$m{\ell}$), and anti-lipid peroxidation activity value of 94.6% (concentration of 10 mg/$m{\ell}$). M80 extract showed the high content of total phenolic (319.7 mg GAE/$m{\ell}$ extract) and total flavonoid (111.6 mg QE/$m{\ell}$ extract). Phenolic and flavonoid compounds showed significant relationship in DPPH radical scavenging ($R^2$=0.911 and 0.912, each extract) and reducing power ($R^2$=0.903 and 0.837, each extract) from fermented R. verniciflua stem bark. However, antilipid peroxidation activity ($R^2$=0.589 and 0.441, each extract) was not significant like DPPH radical scavenging and reducing power. Therefor the result indicated that the potential antioxidant activities and functional values were ovserved significantly at M80 solvent condition from the fermented R. verniciflua stem bark.

EFFECT OF LOW - POWER LASER IRRADIATION ON PAIN RESPONSE (저출력 레이저조사가 동통반응에 미치는 영향)

  • Kim, Sung-Kyo;Yoon, Soo-Han;Lee, Jong-Heun
    • Restorative Dentistry and Endodontics
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    • v.16 no.2
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    • pp.85-98
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    • 1991
  • The aim of this study was to investigate the effect of low - power laser used in the medical field for various purposes to suppress pain responses evoked by noxious electrical or mechanical stimuli. After both inferior alveolar nerves and the left anterior digastric muscle of cats under general anesthesia were exposed, a recording electrode for the jaw opening reflex was inserted into the anterior digastric muscle. The right inferior alveolar nerve was dissected under a surgical microscope until the response of the functional single nerve could be evoked by the electrical stimulation of the dental pulp or oral mucosa. The electrical stimulus was applied with a rectangular pulse of 10 ms duration for measuring the threshold intensity of a single nerve fiber in the inferior alveolar nerve which responds to stimulation of dental pulp and oral mucosa. Then a pulse of 1 ms duration was applied for determination of conduction velocity. A noxious mechanical stimulus to the oral mucosa was applied by clamping the receptive field with an arterial clamp. The Ga-As diodide laser(wave length, 904 nm ; frequency, 1,000 Hz) was irradiated to the prepared tooth cavity, inferior alveolar nerve and oral mucosa as a pulse wave of 2 mW for 6 minutes. This was followed by a continuous wave of 15 mW for 3 minutes. The action potential of the nerve and EMG of the digastric muscle evoked by the noxious electrical stimulus and nerve response to noxious mechanical stimulus were compared at intervals of before, immediately after, and at 5, 10, 20, 40, 60 minutes after laser irradiation. The results were as follows: The conduction velocity of the intrapulpal $A{\delta}$- nerve fiber recorded from the inferior alveolar nerve before irradiation had a mean value of $6.68{\pm}2.07m/sec$. The laser irradiation did not affect the conduction velocity of the AS - nerve fiber and did not change the threshold intensity or amplitude of the action potential either. The EMG of the digastric muscle evoked by noxious electrical stimulation to the tooth was not changed by the laser irradiation, whether in latency, threshold intensity or amplitude. The laser irradiated to the receptive field of the oral mucosa which was subjected to noxious stimuli did not affect the amplitude of the action potential or the frequency either.

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Physicochemical Characteristics and Efficacy of Controlled-release Insecticide Formulation (방출조절형(放出調節型) 살충성(殺蟲性) 농약제제(農藥製劑)의 특성(特性)과 약효(藥效)에 관한 연구(硏究))

  • Kim, Jin-Hwa;Oh, Byung-Youl;Oh, Kyeong-Seok;Kim, Sung-Kee;Kim, Mee-Hea;Kim, Young-Koo
    • Korean Journal of Environmental Agriculture
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    • v.14 no.3
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    • pp.289-295
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    • 1995
  • This study was carried out to develop a controlled-release insecticide formulation for the control of rose aphid (Macrosiphum ibarae) in rose and cotton aphid (Myzus persicae) in chrysanthemum (Dendranthema grandiflorum var. Meibung) in greenhouse. Imidacloprid[1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] was chosen as a toxicant. Two synthetic polymers, low density polyethylene(LDPE) and ethylene vinyl acetate(EVA), were used as polymer matrices. The tested plastic sheet formulations were prepared by heat-aided extrusion procedures after mixing imidacloprid technical and the polymers of three different combinations, and physicochemical properties as well as efficacy of the formulations were investigated. The amounts of imidacloprid recovered and incorporated in the formulations were recorded over 90% and 80%, respectively. Release of the active ingredient from the formulations was remarkably affected by mixing rates of polymers. The active ingredient in the formulations was chemically unstable with over 10% degradation rates after 90 day storage at $50{\pm}2^{\circ}C$. The residual amounts of imidacloprid in the soil treated with the formulations were paralleled with the release pattern of the formulations. Efficacy of the formulations on rose and cotton aphid was maintained over 90% even 120days after treatment under greenhouse.

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Comparison of conservative therapy and steroid therapy for Bell's palsy in children

  • Yoo, Hye Won;Yoon, Lira;Kim, Hye Young;Kwak, Min Jung;Park, Kyung Hee;Bae, Mi Hye;Lee, Yunjin;Nam, Sang Ook;Kim, Young Mi
    • Clinical and Experimental Pediatrics
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    • v.61 no.10
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    • pp.332-337
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    • 2018
  • Purpose: Bell's palsy is characterized by sudden onset of unilateral facial weakness. The use of corticosteroids for childhood Bell's palsy is controversial. This study aimed to identify clinical characteristics, etiology, and laboratory findings in childhood Bell's palsy, and to evaluate the efficacy of corticosteroid treatment. Methods: We conducted a retrospective analysis of children under 19 years of age treated for Bell's palsy between January 2009 and June 2017, and followed up for over 1 month. Clinical characteristics, neuroimaging data, laboratory findings, treatments, and outcomes were reviewed. Patients with Bell's palsy were divided into groups with (group 1) and without (group 2) corticosteroid treatment. Differences in onset age, sex, laterality, infection and vaccination history, degree of facial nerve palsy, and prognosis after treatment between the groups were analyzed. Results: One hundred patients were included. Mean age at presentation was $7.4{\pm}5.62years$. A total of 73 patients (73%) received corticosteroids with or without intravenous antiviral agents, and 27 (27%) received only supportive treatment. There was no significant difference in the severity, laboratory findings, or neuroimaging findings between the groups. Significant improvement was observed in 68 (93.2%) and 26 patients (96.3%) in groups 1 and 2, respectively; this rate was not significantly different between the groups (P=0.48). Conclusion: Childhood Bell's palsy showed good prognosis with or without corticosteroid treatment; there was no difference in prognosis between treated and untreated groups. Steroid therapy in childhood Bell's palsy may not significantly improve outcomes.

Development of Real-time and Simultaneous Quantification of Volatile Organic Compounds in Ambient with SIFT-MS (Selected Ion Flow Tube-Mass Spectrometry) (선택적다중이온질량분석기를 이용한 대기 중 휘발성유기화합물 실시간 동시분석법 개발 및 적용)

  • Son, Hyun Dong;An, Joon Geon;Ha, Sung Yong;Kim, Gi Beum;Yim, Un Hyuk
    • Journal of Korean Society for Atmospheric Environment
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    • v.34 no.3
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    • pp.393-405
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    • 2018
  • Volatile organic compounds (VOCs) are representative air pollutants due to their detrimental effects on human health and their role in formation of secondary organic aerosols. Assessments and monitoring programs of VOCs using periodic grab sampling like Tedlar bags, canisters, and sorbent traps provide limited information, often with delay times of days or weeks. Selected ion flow tube mass spectrometry (SIFT-MS) is an emerging analytical technique for the real-time quantification of VOCs in air. It relies on chemical ionization of the VOCs molecules in air introduced into helium carrier gas using $H_3O^+$, $NO^+$, and $O_2{^+}$ precursor ions. Real-time monitoring method of 60 VOCs in the ambient air was developed using TO-15 standard gas mixture. Calibration curves, method detection limit, and quantitation reproducibility of the target compounds were tested. Dynamic dilution system was used to dilute standard gas from 0.174 ppbv to 100 ppbv, where calibration curves showed good linearity with $r^2$> 0.95 in all target analytes. Limit of detection (LOD) all compounds were sub ppbv, and some halogenated compounds showed pptv levels. Seven consecutive analyses of target compounds showed good repeatability with relative standard deviation of less than 10%. One day monitoring of VOCs in ambient air was conducted in Geoje. Average concentration of target VOCs in Geoje were relatively lower than other regions, among which formaldehyde showed the highest concentration ($15.4{\pm}5.78ppbv$). SIFT-MS provided good temporal resolution data (1 data per 3.2 minute), which can be used for identifying ephemeral short-term event. It is expected that SIFT-MS will be a versatile monitoring platform for VOCs in ambient air.

Research and Policy Directions against Ambient Fine Particles (초미세먼지 문제 해결을 위한 연구 및 정책 방향)

  • Kim, Yong Pyo
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.3
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    • pp.191-204
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    • 2017
  • Concerns on the air pollution problem caused by ambient fine particles have become a big social issue in Korea. Important factors that should be addressed to develop effective and efficient air quality management policy, especially, against fine particles are discussed and research and policy directions to address these factors are suggested. It is suggested that two factors are in high priority; one is scientific understanding of the major formation mechanisms of fine particles and the other is the process of policy decision and implementation. For the scientific understanding, smog chamber measurement, intensive field study, and chemical transport model development that can simulate the characteristics of Northeast Asia are considered to be important. For the policy directions, priority setting of the proposed policies and development and implement of effective communication sytem are considered to be important.

Effects of Feeding Extruded Soybean, Ground Canola Seed and Whole Cottonseed on Ruminal Fermentation, Performance and Milk Fatty Acid Profile in Early Lactation Dairy Cows

  • Chen, P.;Ji, P.;Li, Shengli
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.2
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    • pp.204-213
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    • 2008
  • Four ruminally cannulated Holstein cows averaging 43 days in milk (DIM) were used in a $4{\times}4$ Latin square to determine the effect of feeding extruded soybean, ground canola seed and whole cottonseed on ruminal fermentation and milk fatty acid profile. One hundred and twenty lactating Holstein cows, 58 (${\pm}31$) DIM, were assigned to four treatments in a completely randomized block design to study the effects of the three types of oilseeds on production parameters and milk fatty acid profile. The four diets were a control diet (CON) and three diets in which 10% extruded soybean (ESB), 5% ground canola seed (GCS) and 10% whole cottonseed (WCS) were included, respectively. Diets consisted of concentrate mix, corn silage and Chinese wild rye and were balanced to similar concentrations of CP, NDF and ADF. Ruminal fermentation results showed that ruminal fermentation parameters, dry matter intake and milk yield were not significantly affected by treatments. However, compared with the control, feeding cows with the three oilseed diets reduced C14:0 and C16:0 and elevated C18:0 and C18:1 concentrations in milk, and feeding ESB increased C18:2 and cis9, trans11 conjugated linoleic acid (CLA). Production results showed that feeding ESB tended to increase actual milk yield (30.85 kg/d vs. 29.29 kg/d) and significantly decreased milk fat percentage (3.53% vs. 4.06%) compared with CON. Milk protein (3.41%) and solid non-fat (13.27%) from cows fed WCS were significantly higher than from cows fed CON (3.24% and 12.63%, respectively). Milk urea N concentrations from cows fed the ESB (164.12 mg/L) and GCS (169.91 mg/L) were higher than cows fed CON (132.31 mg/L). However, intake of DM, 4% fat corrected milk, energy corrected milk, milk fat and protein yields, milk lactose percentage and yield, somatic cell count and body condition score were not affected by different treatments. The proportion of medium-chain fatty acid with 14 to 16 C units in milk was greatly decreased in cows fed ESB, GCS and WCS. Feeding ESB increased the concentration in milk of C18:1, C18:2, C18:3 and cis9, trans11-CLA content by 16.67%, 37.36%, 95.24%, 72.22%, respectively, feeding GCS improved C18:0 and C18:1 by 17.41% and 33.28%, respectively, and feeding WCS increased C18:0 by 31.01% compared with feeding CON. Both ruminal fermentation and production trial results indicated that supplementation of extruded soybean, ground canola seed and whole cottonseed could elevate the desirable poly- and monounsaturated fatty acid and decrease the medium chain fatty acid and saturated fatty acid content of milk fat without negative effects on ruminal fermentation and lactation performance.

A Study on the Distribution and Composition of Floating Debris in the Coast of Korea II. Transport of Debris in Middle Part of Southern Sea (연안어장의 부유성 폐기물 분포와 조성에 관한 연구 II. 남해 중부해역의 폐기물 수송)

  • KIM Jong-Hwa
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.3
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    • pp.338-344
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    • 1999
  • Floating debris was recorded from a training ship, $\sharp$1 Kwanaksan, of Pukyong National University with about 10 knots speed at July 15th and 20th of 1997. The sampled area is the middle of southern sea of Korea, divided into 44 unit segments on survey routes. Debris fabrication materials were categorized with 6 items using the following; man-made or natural wood items, paper and cardboard, nylon netting and rope, styrofoam, plastics, floating metal and glass containers. All identified items within a 100 $\pm$ 2 m wide band were recorded but ignored if beyond this boundary. The results of distribution and transport of floating debris in the area are as follows: 1. The quantities of debris during the survey were distributed from $1.6\~369.7\;items/km^2$. The most obvious trend is the widespread distribution of all debris. The highest densities of all debris were discovered in the coastal waters of Namhae and Yokji island, and of about 50 km off from the southward of Yokji and about 74 km off from the eastward of Komun island. Especially many of small styrofoams within $\phi$20 cm were observed in these segments. 2. Styrofoams and plastics were composed of $83.5\%$ among all debris, next woods items, $9.8\%$. 3. The quantities, distribution shapes and composition of debris were varied as the observed duration and the natures of each items. 4. These phenomena are concluded that firstly they depend on the river discharges included debris due to precipitation falls, secondly inflow or dumping debris are drifting to the off-shore by Kuroshio currents present at their adjacent sea, But on the basis of the observed data it is difficult that source position, quantities and inflow items of debris are identified, and also the transport processes is pursue. further more surveys are continuously being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps on all sites of the Coast of Korea and contributed to the stationary area, finding of sources, removal method of debris and resistants of marine productivity.

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Effect of Electron-beam Irradiaton on the Artificial Bone Substitutes Composed of Hydroxyapatite and Tricalcium Phosphate Mixtures with Type I Collagen (수산화인회석과 인산삼칼슘 및 1형 콜라젠 혼합골의 전자빔 조사 효과)

  • Park, Jung Min;Kim, Soung Min;Kim, Min Keun;Park, Young Wook;Myoung, Hoon;Lee, Byung Cheol;Lee, Jong Ho;Lee, Suk Keun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.35 no.1
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    • pp.38-50
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    • 2013
  • Purpose: The aim of this study is to evaluate the effect and potential of electron beam (E-beam) irradiation treatment to the synthetic bony mixtures composed of hydroxyapatite (HA; Bongros$^{(R)}$, Bio@ Co., Korea) and tricalcium phosphate (${\beta}$-TCP, Sigma-Aldrich Co., USA), mixed at various ratios and of type I collagen (Rat tail, BD Biosciences Co., Sweden) as an organic matrix. Methods: We used 1.0~2.0 MeV linear accelerator and 2.0 MeV superconductive linear accelerator (power 100 KW, pressure 115 kPa, temperature $-30{\sim}120^{\circ}C$, sensor sensitivity 0.1~1.2 mV/kPa, generating power sensitivity 44.75 mV/kPa, supply voltage $5{\pm}0.25$ V) with different irradiation dose, such as 1, 30 and 60 kGy. Structural changes in this synthetic bone material were studied in vitro, by scanning electron microscopy (SEM), elementary analysis and field emission scanning electron microscope (FE-SEM), attenuated total reflection (ATR), and electron spectroscopy for chemical analysis (ESCA). Results: The large particular size of HA was changed after E-beam irradiation, to which small particle of TCP was engaged with organic collagen components in SEM findings. Conclusion: The important new in vitro data to be applicable as the substitutes of artificial bone materials in dental and medical fields will be able to be summarized.

The Present State of an Air Pollutants Inflow into Gyeongju and Effects on Stone Cultural Properties (경주권역으로의 대기오염물질 유입현황과 석조문화재에 미치는 영향)

  • Jung, Jong-Hyeon;Shon, Byung-Hyun;Kim, Hyun-Gyu;Choi, Won-Joon;Nam, Chul-Hyun
    • Journal of Environmental Health Sciences
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    • v.31 no.5 s.86
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    • pp.349-359
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    • 2005
  • In this study, we focused on the geographical and the meterological conditions, the atmospheric examination, the soil contents and compositions in order to establish cultural properties conservation plan in Gyeongju and its surroundings. Also, the transport route with environmental contaminants in Ulsan and Pohang was examined. The results could be summarized as follows ; Air pollutant and environmental contaminant was transported by two types of winds. One is induced by local winds, the other is induced by synoptic winds. Air contaminant transported from coastal regions to inland regions were associated with wind velocity. Gyeongju had good atmospheric conditions, i.e. $SO_2\;0.009{\sim}0.011ppm,\;CO\;0.6{\sim}0.8ppm,\;NO_2\;0.015{\sim}0.020ppm,\;O_3\;0.017{\sim}0.032ppm,\;PM_{10}\;46{\sim}62{\mu}g/m^3\;and\;Pb\;0.034{\sim}0.060{\mu}g/m^3$, which was below environmental air qualify standards and was little lower than those of Pohang and Ulsan. However, Ulsan and Pohang city are located on south-east coast and have many industrial facilities. Hence, air pollution problems become serious issues in Ulsan, Pohang, Busan, Daegu and other cities due to the emission of air pollutants from the various industrial facilities, incinerator and power plants, etc. The soil of Gyeongju had heavy metals conditions, i.e. $Cd\;0.01{\sim}0.08mg/kg,\;Cu\;N.D{\sim}2.39mg/kg,\;As\;N.D{\sim}0.07mg/kg,\;Hg\;N.D{\sim}0.15mg/kg,\;Pb\;0.49{\sim}1.39mg/kg,\;Cr^{+6}\;0.02{\sim}0.42mg/kg,\;Fe\;0.74{\sim}1.55mg/kg,\;Mn\;0.11{\sim}0.49mg/kg\;and\;Zn\;1.11{\sim}3.56mg/kg$. However, pH value of soil had range of $4.12{\sim}7.45$. The results showed that high pH concentration of soil could occur due to air pollution diffusion and environmental contaminant transport at Ulsan and Pohang city.