• Title/Summary/Keyword: Intensity limit

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Determination of Terazocin in Human Plasma by Liquid Chromatography and Bioequivalence Study of Teratonin® Tablets (액체크로마토그래프법에 의한 사람 혈장 중 테라조신의 정량 및 테라토닌® 정의 생물학적 동등성)

  • Cho, Eun-Sook;Kang, Sung-Ha;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.32 no.2
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    • pp.119-125
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    • 2002
  • A rapid, selective and reproducible high-performance liquid chromatographic method has been developed for the determination of terazocin in human plasma. Terazocin plus the internal standard, prazocin hydrochloride, were extracted from alkalified plasma with tert-butylmethyl ether, back-extracted into 0.05% phosphoric acid. Fifty ${\mu}l-portions$ of extract were injected onto a octadecylsilane column and eluted with a mixture of acetonitrile, water and triethylamine (30 : 70 : 0.1 v/v, adjusted to pH 5.0 with dilute phosphoric acid) at a flow rate of 1.0 ml/min. The fluorescence intensity of column eluents was monitored at excitation wavelength of 250 nm and emission wavelength of 370 nm. No interference peaks were observed. The practical limit of quantitation was 5 ng/ml for terazocin. The average intraday and interday coefficients of variation were 4.15 and 3.54%, respectively. Also intraday and interday precisions over the range $5{\sim}60\;ng/ml$ were $0.49{\sim}2.92\;and\;0.38{\sim}5.12%$, respectively. The bioequivalence of two terazosin tablets, the $Hytrine^{\circledR}$ (Il Yang Pharmaceutical Co., Ltd.) and the $Teratonin^{\circledR}$ (Sam-A Pharmaceutical Co., Ltd.), was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Sixteen healthy male volunteers $(24.6{\pm}2.0\;years\;old)$ were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 2 mg of terazosin was orally administered, blood was taken at predetermined time intervals and the concentration of terazosin in plasma was determined with a HPLC method using spectrofluorometric detector. AUC was calculated by the linear trapezoidal method. $C_{max}\;and\;T_{max}$ were compiled from the plasma drug concentration-time data. Analysis of variance (ANOVA) was utilized for the statistical analysis of the parameters. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between the two preparations were 0.21 %, 5.53% and 8.82%, respectively. The powers $(1-{\beta})\;for\;AUC_t,\;C_{max}\;and\;T_{max}$ were >99%, 97.49%, and 33.26%, respectively. Minimum detectable differences $({\Delta},\;%)\;at\;{\alpha}=0.1\;and\;1-{\beta}=0.8$ and the 90% confidence intervals were all less than ${\pm}20%$ except for $T_{max}.\;AUC_t\;and\;C_{max}$ met the criteria of KDFA for bioequivalence, indicating that $Teratonin^{circledR}$ tablets are bioequivalent to $Hytrine^{circledR}$ tablets.

A predictive model to guide management of the overlap region between target volume and organs at risk in prostate cancer volumetric modulated arc therapy

  • Mattes, Malcolm D.;Lee, Jennifer C.;Elnaiem, Sara;Guirguis, Adel;Ikoro, N.C.;Ashamalla, Hani
    • Radiation Oncology Journal
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    • v.32 no.1
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    • pp.23-30
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    • 2014
  • Purpose: The goal of this study is to determine whether the magnitude of overlap between planning target volume (PTV) and rectum ($Rectum_{overlap}$) or PTV and bladder ($Bladder_{overlap}$) in prostate cancer volumetric-modulated arc therapy (VMAT) is predictive of the dose-volume relationships achieved after optimization, and to identify predictive equations and cutoff values using these overlap volumes beyond which the Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) dose-volume constraints are unlikely to be met. Materials and Methods: Fifty-seven patients with prostate cancer underwent VMAT planning using identical optimization conditions and normalization. The PTV (for the 50.4 Gy primary plan and 30.6 Gy boost plan) included 5 to 10 mm margins around the prostate and seminal vesicles. Pearson correlations, linear regression analyses, and receiver operating characteristic (ROC) curves were used to correlate the percentage overlap with dose-volume parameters. Results: The percentage $Rectum_{overlap}$ and $Bladder_{overlap}$ correlated with sparing of that organ but minimally impacted other dose-volume parameters, predicted the primary plan rectum $V_{45}$ and bladder $V_{50}$ with $R^2$ = 0.78 and $R^2$ = 0.83, respectively, and predicted the boost plan rectum $V_{30}$ and bladder $V_{30}$ with $R^2$ = 0.53 and $R^2$ = 0.81, respectively. The optimal cutoff value of boost $Rectum_{overlap}$ to predict rectum $V_{75}$ >15% was 3.5% (sensitivity 100%, specificity 94%, p < 0.01), and the optimal cutoff value of boost $Bladder_{overlap}$ to predict bladder $V_{80}$ >10% was 5.0% (sensitivity 83%, specificity 100%, p < 0.01). Conclusion: The degree of overlap between PTV and bladder or rectum can be used to accurately guide physicians on the use of interventions to limit the extent of the overlap region prior to optimization.

Analysis of Quartz Content and Particle Size Distribution of Airborne Dust from Selected Foundry Operations (주물사업장 주공정별 발생하는 분진의 석영함유량 및 크기분포 연구)

  • Phee, Young Gyu;Roh, Young Man;Lee, Kwang Mook;Kim, Hyoung-Ah;Kim, Yong Woo;Won, Jeoung Il;Kim, Hyunwook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.7 no.2
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    • pp.196-208
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    • 1997
  • This study was performed to estimate quartz contents in the both bulk and airborne dust samples and to determine particle size distribution of airborne dust from the selected foundry operations. Total dust samples were collected by a 37mm cassette and respirable by a 10 mm nylon cyclone. Particle size distributions were determined by a Marple's 8-stage cascade impactor at the melting, molding, shakeout and finishing operations. The presence of elements in the dust samples were confirmed by the scanning electron microscopy equipped with the energy dispersive x-ray spectrometry. The quartz contents were estimated using the intensity of the absorption peak of quartz at 799 cm-l by the Fourie Transformed Infrared Spectroscopy (FTIR). The results were as follows: 1. The analysis of data from cascade Impactor showed bimodal distributions of particle size at the melting, molding and shakeout operations. Mass median aerodynamic diameters for the distributions determined by histogram were $0.48-1.65{\mu}m$ for small and $13.43-19.58{\mu}m$ for large modes. In the dust samples collected at the finishing operations, however, only a large mode of $18.89{\mu}m$ was found. 2. The percentages of total to respirable dust concentration calculated from the impactor data ranged from 42 % to 66 %. The average concentrations of respirable dust by cyclone were $0.85-1.28mg/m^3$ collected from the workers, and were $0.23-0.56mg/m^3$ from the areas surveyed. Dust concentrations of personal samples were statistically significantly higher than those of area samples. The highest dust concentration was obtained from the personal samples of the finishing operation. 3. The mean percentages of silicon and oxygen estimated by SEM-EDXA in the bulk samples ranged from 35.83 % to 36.02 % and from 39.93 %-41.64 %, respectively. 4. The average quartz contents estimated by FTIR in the respirable dust from personal samples ranged from 4.32 % to 5.36 % and 4.54 % to 4.70 % in the bulk samples. No statistical difference of quartz content was found between foundry operations. In this study, quartz content was quantified by FTIR. Although no statistically significant difference in quartz content between airborne and bulk, samples and between different foundry operations was found, it is recommended that quartz content in the individual sample of respirable dust be analyzed and the results be used either to select an applicable quartz limits or to calculate the exposure limit. Further studies, however, are needed to compare the results by FTIR and XRD since it is reported that the quartz content determined by FTIR is different from that by XRD.

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Immunological Aspects of Contemporary Exercise (운동과 면역반응에 대한 고찰)

  • Kwak, Yi-Sub;Kim, Chul-Woo;Paik, Young-Ho
    • Journal of Life Science
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    • v.17 no.8 s.88
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    • pp.1166-1171
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    • 2007
  • Exercise is the strongest stress to which the body is ever exposed. The body responds to this stress through a set of physiological changes in its metabolic, hormonal, and immunological systems. In this study, responses of the immune system to the long-term aerobic and anaerobic exercises have been investigated. Regular moderate exercise is associated with a reduced incidence of infection compared with a sedentary groups. Aerobic training increases the heart rate and enhances the body's intake of oxygen long enough to benefit the condition of the body. In recent years, the importance of exercise in everyday life has been rapidly increasing. Moderate exercise appears to stimulate the immune system. And also, Exercise elicits an increase in the numbers of circulating lymphocytes and lymphocyte subsets (including NK cells) which is followed by a decrease in the numbers of cells during recovery from exercise. However, prolonged bouts of strenuous exercise cause a temporary depression of various aspects of immune functions (e.g. lymphocyte proliferation, monocyte antigen presentation, open window periods, exercise induced asthma, exercise induced anaphylaxis) that usually lasts 2-24 hr after exercise depending on the intensity and duration of the exercise bout. Exercise-induced bronchoconstriction (EIB) was defined as a decrease of at least 15% in pre exercise forced expiratory volume in one second at any time point after exercise. This includes elevation of cortisol and cathecholamines in plasma. On the other hand, highly trained athletes exhibit a chronic mild hypercortisolism at baseline that maybe an adaptive change to chronic exercise. And, Consuming carbohydrate during prolonged strenuous exercise attenuates rises in stress hormones and appears to limit the degree of exercise-induced immune depression. Recent evidence suggests that antioxidant vitamin supplementation may also reduce exercise stress and impairment of leukocyte functions.

The Study on the Characteristic Sound Intensity and Frequency of Noise Exposure at Occupational Sites (산업장 소음의 강도 및 주파수 특성에 관한 조사연구)

  • Kim, Kwang Jong;Cha, Chul Whan
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.1 no.2
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    • pp.181-191
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    • 1991
  • The present study determined the overall noise level and the distribution of sound pressure level over audible frequency range of noise produced at various work sites. Work-related noise greater than 80dBA produced from 98 separate work sites at 37 manufacturing companies and machine shops were analysed for the overall sound level (dBA) and frequency distribution. In addition, to determine the possible hearing loss related to work site noise, a hearing test was also conducted on 1,374 workers in these work sites. The results of the study were as follows ; 1. Of the total 98 work sites, 57 work sites(58.2%) produced noise exceeding threshold limit value (${\geq}90dBA$) set by the Ministry 01 Labor. In terms of different manufacturing industries the proportion of work sites which exceeded 90dBA was the highest for the cut-stone products industry with 6/6 work sites and lowest for the commercial printing industry with 1/13 work sites. 2. The percentage of workers who were exposed to noise greater than 90dBA was 19.8% (1,040 workers) 01 the total 5,261 workers. In terms of different industries, cut-stone products industry had the most workers exposed to noise exceeding 90dBA with 82.8%, textile bleaching and dyeing industry was next at 30.6% followed by fabricated metal products industry with 27.9%, plastic products manufacturing industry had the lowest percentage of workers exposed to 90dBA exceeding noise with 4.5%. 3. There was a statistically significant correlation between the frequency of noise-induced hearing loss and the percentage of workers exposed to noise exceeding 90dBA (P<0.05). 4. The frequency analysis of noise produced at the 98 work sites revealed that 44 work sites (44.9%) had the maximum sound pressure level at high-frequencies greater than 2KHz. In addition, significantly higher sound pressure level was detected at the high-frequencies at 90dBA exceeding work sites as compared to below 90dBA work sites (P<0.01). 5. The differences in sound level meter's A-and C-weighted sound pressure levels were analysed by frequencies. Of the 28 work sites which showed 0-1 dB difference in the two weighted sound levels, 20 work sites (71.4%) had significantly higher sound pressure levels at high-frequencies greater than 2KHz (P<0.01). Furthermore, there was a tendency for higher sound pressure levels to occur in the high-frequency range as the differences in the two weighted sound levels decreased.

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Simultaneous Determination of Aflatoxins and Ochratoxin A in Pork by LC-MS/MS (LC-MS/MS를 이용한 돼지고기 중 총아플라톡신 및 오크라톡신 A 동시분석법 확립)

  • Paek, Ockjin;Park, Songyi;Park, Ki Hun;Kim, Sheen-Hee;Suh, Saejung;Yoon, Hae Jung
    • Journal of Food Hygiene and Safety
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    • v.31 no.3
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    • pp.194-200
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    • 2016
  • Aflatoxins and ochratoxin A (AFTs and OTA) are secondary fungal metabolites produced by several moulds, mainly by Aspergillus flavus by Aspergillus ochraceus and Penicillium verrucosum, and these toxins can be transferred to animals and humans through the ingestion of contaminated feed and food. This study was to develop the analytical method for determination the levels of AFTs ($B_1$, $B_2$, $G_1$ and $G_2$) and OTA in pork. The AFTs and OTA were analyzed simultaneously by electrospray ionization in positive ion mode and mass reaction monitoring (MRM) after solid phase extract (SPE) columns clean-up. Performance characteristics, such as accuracy, precision, linear range, limit of detection (LOD) and quantification (LOQ), were also determined. Matrix-matched standard calibration was used for quantification, obtaining the recoveries in the range of 67.3~108.2% with the relative standard deviations of < 20%. Limits of detection and quantification were also estimated, obtaining the limits of quantification ranged in $0.7{\sim}1.3{\mu}g/kg$. The results of the inter-day study, which was performed with pork samples for 3 days, showed an accuracy of 92.0~109.9%. The precisions (expressed as relative standard deviation values) for the inter day variation were 2.6~17.8%. The method developed in this study was able to carry out the analysis with the satisfactory intensity and accuracy.

Effects of evacuation delay time and fire growth curve on quantitative risk for railway tunnel fire (철도터널 화재 시 피난개시시간지연 및 화재성장곡선이 정량적 위험도에 미치는 영향)

  • Ryu, Ji-Oh;Kim, Hyo-Gyu;Lee, Hoo-Young
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.20 no.5
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    • pp.809-822
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    • 2018
  • A quantitative risk assessment has been introduced to quantitatively evaluate fire risk as a means of performance based fire protection design in the design of railway tunnel disaster prevention facilities. However, there are insufficient studies to examine the effect of various risk factors on the risk. Therefore, in this study, the risk assessment was conducted on the model tunnel in order to examine the effects of the evacuation start time delay and the fire growth curve on the quantitative risk assessment. As a result of the analysis of the scenario, the fatalities occurred mainly when escapes in the same direction as the direction of the fire smoke movement. In addition, after the FED exceeded 0.3, the maximum fatalities occurred within 10 minutes. In the range of relatively low risk, distance between cross passages, evacuation delay time and fire growth curve were found to affect the risk, but they were found to have little effect on the condition that the risk reached the limit. Especially, in this study, it was evaluated that the evacuation delay time reduction, fire intensity and duration reduction effect were not observed when the distance between cross passages was more than 1500 m.

Design of Network Attack Detection and Response Scheme based on Artificial Immune System in WDM Networks (WDM 망에서 인공면역체계 기반의 네트워크 공격 탐지 제어 모델 및 대응 기법 설계)

  • Yoo, Kyung-Min;Yang, Won-Hyuk;Kim, Young-Chon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.4B
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    • pp.566-575
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    • 2010
  • In recent, artificial immune system has become an important research direction in the anomaly detection of networks. The conventional artificial immune systems are usually based on the negative selection that is one of the computational models of self/nonself discrimination. A main problem with self and non-self discrimination is the determination of the frontier between self and non-self. It causes false positive and false negative which are wrong detections. Therefore, additional functions are needed in order to detect potential anomaly while identifying abnormal behavior from analogous symptoms. In this paper, we design novel network attack detection and response schemes based on artificial immune system, and evaluate the performance of the proposed schemes. We firstly generate detector set and design detection and response modules through adopting the interaction between dendritic cells and T-cells. With the sequence of buffer occupancy, a set of detectors is generated by negative selection. The detection module detects the network anomaly with a set of detectors and generates alarm signal to the response module. In order to reduce wrong detections, we also utilize the fuzzy number theory that infers the degree of threat. The degree of threat is calculated by monitoring the number of alarm signals and the intensity of alarm occurrence. The response module sends the control signal to attackers to limit the attack traffic.

Source Identification for Asian Dust Deposited on Domestic Area Using Sr-Nd Isotope Ratios in Spring, 2007 (Sr-Nd 동위원소를 이용한 국내 퇴적황사의 발원지 규명: 2007년 봄철 황사)

  • Youm, Seung-Jun;Lee, Pyeong-Koo
    • Economic and Environmental Geology
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    • v.41 no.3
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    • pp.315-326
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    • 2008
  • Recently, the occurrence and intensity of Asian Dust have dramatically increased in Korean peninsula, resulting in severe damages to the domestic social and economic field. The most useful way to prevent the damage of Asian Dust is the restraint of the occurrence of Asian Dust itself. However, Asian dust is the one of the natural phenomena, thus there is a basic limit to manage the Asian Dust. Though it is impossible to restrain the occurrence of Asian Dust in short time at present, it is a urgent matter to minimize the damage of Asian Dust. It is necessary to construct the basic data for understanding the harmfulness of Asian Dust, and to elucidate the source area of Asian Dust in connection with the maleficence of itself. In this study, the source area of Asian Dust in spring, 2007, is investigated using the Sr-Nd isotopic ratios which is the most common method to trace the source of geological materials. The relationships of Sr-Nd isotope ratios indicate that Asian Dust was originated from Central Loess Plateau and/or Ordos desert in spring, 2007.

Habitat Characteristics and Distribution of Cymbidium kanran Native to Jejudo, Korea (제주한란의 자생환경 특성 및 분포에 관한 연구)

  • Lee, Jong Suk
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.1
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    • pp.40-49
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    • 2004
  • This work carried out to define the characteristic of Cymbidium kanran habitat at Mt. Halla in Jejudo, Korea from the ecological point of view including geological and topographical features, air and soil temperature, relative humidity, fluctuations of light intensity, habitat vegetation, distribution altitude, area limit, and etc. And another goal of this study consider the conservation counterplan of the cymbidium habitat. Natural distribution areas of the cymbidium were observed more abundantly on the well drained south and east-facing slopes. Soil acidity was ranged from pH 4.1 to 5.3, and electric conductivity was ranged from 176.4 to 299.9 us/cm (average 215.3 us/cm). Base-saturation percentage of the habitat soil was below 50%, bulk density 0.42g/$cm^2$, particle density 2.05g/$cm^2$, humus content 26%, total nitrogen 0.82%, available phosphate 4.2 mg/kg, exchangeable potassium 0.63 Cmol/kg, calcium 0.44 Cmol/kg and magnesium 0.67 Cmol/kg. Annual mean air temperature was $15.4^{\circ}C$, however, air temperature was ranged $11.7{\sim}18.2^{\circ}C$ in spring, $21.2{\sim}23.8^{\circ}C$ in summer, $12.8{\sim}22.0^{\circ}C$ in fall and $5.5{\sim}7.8^{\circ}C$ in winter season. Annual mean soil temperature at depth of 10cm was $13.2^{\circ}C$ And minimum value was recorded $4.7^{\circ}C$ on January, and maximum value $22.5^{\circ}C$ on August. Relative humidity was ranged 90.8~94.7% in summer, 80.8~91.5% in fall and 77.6~84.2% in winter season. Minimum value was 56.5% on December, and maximum value was 100% on July and August. Light intensities were ranged from 400 to 1,800 lux at the greater part of Cymbidium kanran sites in Jejudo. Summer regarded as an lower light intensities was recorded to be range of 500~600 lux; however, autumn and winter were shown higher light regimes ranged from 3,500 to 3,800 lux. Therefore, one must be suprised that the cymbidium grow at the light condition of 6 lux (minimum) or 10,000 lux (maximum). Tree species keeping higher frequency rate and density were Eurya japonica, Camellia japonica, Castanopsis cuspidata, Carpinus laxiflora and Pinus densiflora. Number of trees growing in a 5${\times}$5m quardrat was 35 as an average, and proportion of evergreen versus deciduous was 5:1. Distribution altitude of the orchid habitat was ranged from 120m (low) to 840m (high) from sea level on the south facing slope of Mt. Halla, and was ranged eastern borderline of Gujwaup, Bukjejugun to western boundaries of Jungmundong, Seogwipo city. For the stable conservation of Cymbidium kanran habitat, sunlight regimes must be increased more by means of cutting trees or twigs in the site.