• Journal of agricultural medicine and community health
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• v.29 no.2
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• pp.303-314
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• 2004

Objectives: This study was carried out to assess exposure levels of organic dusts and ammonia in poultry farms in Korea. Methods: A total of six poultry farms were investigated. The farms were located in Namwon, Chonlabuk-do and in Kae-San, Chungchongbuk-do. This study consisted of a questionnaire and measuring organic dusts and ammonia. The questionnaire included the characteristics of the farms, work patterns and the tasks of the poultry farms. Results and Conclusions: The farmers raised the chickens 45 times a year and the average number of years in the poultry farm were eight years ranging from 2 to 12 years. They worked for seven days per week and the average hours spent caring the chickens are 6.3 hours per day. The duration of staying in the confinement buildings was 3.3 hours per day. The work time in summer was longest. The feed and the water supply systems were automatic and the control of ventilation windows used "winch curtain" was semiautomatic. They used mechanical ventilation system in winter and used dilution ventilation system in the other seasons. The geometric mean concentration of total and respirable dust sampled in the poultry confinement buildings was 4.0 mg/$m^3$and 0.9 mg/$m^3$ respectively. The ratio of respirable to total dusts range from 9 to 49 percent. There was no sample exceeding the criteria 10 mg/$m^3$ for total dust and 3 mg/$m^3$ for respirable dust in farms. The criteria have been recommended by Korean Ministry of Labor and American Conference of Governmental Industrial Hygienist. The personal respirable dusts measured during a circle work averaged geometric mean concentration 1.4 mg/$m^3$ Two personal samples were exceeded the threshold 3 mg/$m^3$. There was a positive relation between an index and the personal samples of respirable dusts($R^2$=0.98). The index is calculated by multipling the total number of chickens in the farm by the age of the chickens and then dividing by the volume of the confinement building. The geometric mean concentration of area and personal ammonia samples was 23.3 ppm and 22.2 ppm, respectively. Some of the ammonia samples, both area and personal samples, exceeded the short term exposure limit value 35 ppm.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.3
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• pp.223-233
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• 2015

In order to evaluate the pollution of heavy metals in offshore surface sediments around shipyards in Korea, surface sediment samples were collected at eleven stations around four major shipyards located in the southeastern coast of Korea in summer 2010 and nine kinds of heavy metals such as copper(Cu), zinc(Zn), cadmium(Cd), lead(Pb), chrome(Cr), arsenic(As), mercury(Hg), iron(Fe) and aluminum(Al) in sediments were analyzed. The concentrations of Cu at all sampling stations were in the range of 47.10~414.96 mg/kg and exceeded TEL(Threshold Effects Level) 20.6 mg-Cu/kg of Korean marine environmental standards for offshore sediments and ERL(Effect Range-Low) 34.0 mg-Cu/kg. The concentrations of Cu at seven stations around four shipyards were 65.18~414.96 mg/kg and exceeded PEL(Probable Effects Level) 64.4 mg-Cu/kg of Korean marine environmental standards for offshore sediments. The concentration of Cu at one station around B-shipyard was 414.96 mg/kg and exceeded ERM(Effect Range-Median) 270.0 mg-Cu/kg. The concentrations of Zn at all stations were in the range of 135.09~388.79 mg/kg which exceeded ERL 150.0 mg-Zn/kg. The concentrations of Zn at seven stations around four shipyards were 157.57~388.79 mg/kg and exceeded PEL 157.0 mg-Zn/kg. The concentration of Zn at one station around B-shipyard was 388.79 mg/kg and was approaching ERM 410.0 mg-Zn/kg. The concentrations of Cd at all stations were in the range of 0.11~0.54 mg/kg and were below TEL 0.75 mg-Cd/kg and ERL 1.2 mg-Cd/kg. The concentrations of Pb at all stations were in the range of 18.04~105.62 mg/kg. The concentrations of Pb at two stations around B-shipyard were 73.87~105.62 mg/kg which exceeded TEL 44.0 mg-Pb/kg and ERL 46.7 mg-Pb/kg, and were below PEL 119.0 mg-Pb/kg and ERM 218.0 mg-Pb/kg. The concentrations of Cr at all stations were in the range of 51.26~85.39 mg/kg. The concentration of Cr at one station around B-shipyard was 85.39 mg/kg and exceeded ERL 81.0 mg-Cr/kg. The concentrations of As at all stations were in the range of 8.70~22.15 mg/kg which exceeded ERL 8.2 mg-As/kg and were below ERM 70.0 mg-As/kg. The concentrations of As at eight stations around A-shipyard, B-shipyard and D-shipyard were 14.93~22.15 mg/kg which exceeded TEL 14.5 mg-As/kg and were below PEL 75.5 mg-As/kg. The concentrations of Hg at all stations were in the range of 0.02~0.35 mg/kg. The concentrations of Hg at three stations around A-shipyard were 0.11~0.13 mg/kg which were almost equal to TEL 0.11 mg-Hg/kg. Those at two stations around B-shipyard were 0.27~0.35 mg/kg which exceeded TEL 0.11 mg-Hg/kg and ERL 0.15 mg-Hg/kg, and were below PEL 0.62 mg-Hg/kg and ERM 0.71 mg-Hg/kg. The concentrations of Fe and Al at all stations were in the range of 2.90 3.66 % and 3.12 6.80 %, respectively. These results imply that heavy metals such as copper, zinc, lead, arsenic and mercury were likely to be transferred to marine environment from shipyards, especially from B-shipyard.

• Journal of the Korean earth science society
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• v.37 no.7
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• pp.434-447
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• 2016

This study analyzed mass concentrations of PM10 and PM2.5, as measured at Tae-ahn and Gang-nae, Cheongju in central Korea over the period from 2011 to 2015. Higher mass concentrations of PM10, with the exception of dustfall cases during the period of winter and spring, reflected the influence of a prevailing westerly airflow, while the level of PM10 stayed at a low level in summer, reflecting the influence of North Pacific air mass and frequent rainfall. Accordingly, cases where a daily PM10 average of $81{\mu}gm^{-3}$ or over (exceeding the status of fine dust particles being 'a little bit bad') were often observed during the period of winter and spring, with more cases occurring in parts of Tae-ahn that are located close to the sources of pollutant emission in eastern China. Dustfall usually originated from dust storms made up of particles $2.5{\mu}m$ or over in diameter. However, anthropogenic haze displayed a high composition ratio of particulate less than $2.5{\mu}m$ in diameter. Accordingly, brightness temperature difference (BTD) values from the Communication, Ocean and Meteorological Satellite (COMS) were $-0.5^{\circ}K$ or over in haze with fine particulate. PM10 mass concentrations and NOAA 19 satellite BTD for haze cases were analyzed. Though PM10 mass concentrations were found to be lower than $200{\mu}g\;m^{-3}$, the mass concentration ratio of PM2.5/PM10 was measured as higher than 0.4 and BTD was found to be distributed in the range from -0.3 to $0.5^{\circ}K$. However, the BTD of dustfall cases exceeding $190{\mu}g\;m^{-3}$, were found to be less than 0.4 and BTD was found to be distributed in the range less than $-0.7^{\circ}K$. The result of applying BTD threshold values of the large-scale transport of haze proved to fall into line with the range over which aerosols of MODIS AOD and OMI AI were distributed.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1031-1031
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• 2001

The mammary gland is made up of remarkably sensitive tissue, which has the capability of producing a large volume of secretion, milk, under normal or healthy conditions. When bacteria enter the gland and establish an infection (mastitis), inflammation is initiated accompanied by an influx of white cells from the blood stream, by altered secretory function, and changes in the volume and composition of secretion. Cell numbers in milk are closely associated with inflammation and udder health. These somatic cell counts (SCC) are accepted as the international standard measurement of milk quality in dairy and for mastitis diagnosis. NIR Spectra of unhomogenized composite milk samples from 14 cows (healthy and mastitic), 7days after parturition and during the next 30 days of lactation were measured. Different multivariate analysis techniques were used to diagnose the disease at very early stage and determine how the spectral properties of milk vary with its composition and animal health. PLS model for prediction of somatic cell count (SCC) based on NIR milk spectra was made. The best accuracy of determination for the 1100-2500nm range was found using smoothed absorbance data and 10 PLS factors. The standard error of prediction for independent validation set of samples was 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. It has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. From the spectral changes, we learned that when mastitis occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk. It was consistent with the results we obtained further when applied 2DCOS. Two-dimensional correlation analysis of NIR milk spectra was done to assess the changes in milk composition, which occur when somatic cell count (SCC) levels vary. The synchronous correlation map revealed that when SCC increases, protein levels increase while water and lactose levels decrease. Results from the analysis of the asynchronous plot indicated that changes in water and fat absorptions occur before other milk components. In addition, the technique was used to assess the changes in milk during a period when SCC levels do not vary appreciably. Results indicated that milk components are in equilibrium and no appreciable change in a given component was seen with respect to another. This was found in both healthy and mastitic animals. However, milk components were found to vary with SCC content regardless of the range considered. This important finding demonstrates that 2-D correlation analysis may be used to track even subtle changes in milk composition in individual cows. To find out the right threshold for SCC when used for mastitis diagnosis at cow level, classification of milk samples was performed using soft independent modeling of class analogy (SIMCA) and different spectral data pretreatment. Two levels of SCC - 200 000 cells/$m\ell$ and 300 000 cells/$m\ell$, respectively, were set up and compared as thresholds to discriminate between healthy and mastitic cows. The best detection accuracy was found with 200 000 cells/$m\ell$ as threshold for mastitis and smoothed absorbance data: - 98% of the milk samples in the calibration set and 87% of the samples in the independent test set were correctly classified. When the spectral information was studied it was found that the successful mastitis diagnosis was based on reviling the spectral changes related to the corresponding changes in milk composition. NIRS combined with different ways of spectral data ruining can provide faster and nondestructive alternative to current methods for mastitis diagnosis and a new inside into disease understanding at molecular level.

• Journal of Ginseng Research
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• v.33 no.2
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• pp.104-110
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• 2009

It is well known that the saponin of Korean red ginseng (KRG) has an anti-oxidant effect and could suppress the accumulation of lipid peroxidation. The aim of the present study was to observe the inhibitory effect of KRG on mice with noise-induced hearing loss, and to determine its optimal dose. BALB/c mice with a normal hearing level and normal Preyer's reflexes were used in the study. The mice in the permanent-threshold-shift (PTS) group were exposed to noise (120-dB SPL, white noise band) in a noise booth for 3 h a day, for three consecutive days. The mice in the experimental group were given heat-processed red-ginseng extract (50 mg/kg, 100 mg/kg, and 200 mg/kg), and those in the control group were given normal saline alone during their noise exposure. The mice in the temporary-threshold-shift (TTS) group were exposed to noise (120 dBSPL, white noise band) in a noise booth for 3 h. The mice in the experimental group were given heat-processed red-ginseng extract (50 mg/kg, 100 mg/kg, and 200 mg/kg), and those in the control group were given normal saline alone before their noise exposure. The hearing levels of the mice were measured through auditory brainstem response (ABR) immediately and I, 3, 5, 7, and 14 days after their noise exposure. Cochleae were removed from the mice 14 days after their noise exposure. lmmunochemical and immunofluorescent staining were performed to observe the expression of 8-oxoG in cochlea. In the PTS group, the hearing function of the mice in all the groups was not recovered after their noise exposure. In the TTS group, however, the hearing function of the mice in all the groups was recovered within 14 days. Reduced hearing impairment and early recovery were observed in the mice that were given 200 mg/kg KRG, and early recovery was observed in the mice that were given 100 mg/kg KRG The immunopositive staining of 8-oxoG was detected in the stria vascularis in the control group but was diminished in the mice that were given 200 mg/kg KRG The ingestion of more than 100 mg/kg KRG demonstrated a protection and recovery effect on the noiseinduced-TTS group. Since KRG has been reported to be a safe compound even up to hundreds of mg/kg, a higher concentration of it may effectively protect and recover TTS.

• Journal of fish pathology
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• v.26 no.2
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• pp.65-75
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• 2013

Population growth equation of scuticociliate Miamiensis avidus was obtained from the experimental results of in vitro culture condition to estimate the growth rate and carrying capacity from the growth equation. In addition, intraperitoneal infections into olive flounder Paralichthys olivaceus were carried out into 2 different conditions: different concentrations of M. avidus in same water temperature and same concentration of M. avidus in different water temperatures. Olive flounder mortality was threshold dependent with both the temperature and M. avidus density parameters. In this paper, we propose a mathematical model to study M. avidus growth in olive flounder based upon the interactions between parasite and host. The mathematical model was logistic growth differential equation (1.2). The parameters were found with Matlab program through the Levenberge-Marquardt method. In theorem, equilibrium values between the infected fish population and dead population could found. Our equilibrium points were a stable equilibrium and an unstable equilibrium. From the equation (1.6), it was possible to predict the amount of cumulative mortality of olive flounder along with the time after M. avidus infection.

• Annals of Clinical Neurophysiology
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• v.12 no.1
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• pp.21-26
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• 2010

Background: Although quantitative sensory test (QST) is being used with increasing frequency for measuring sensory thresholds in clinical practice and epidemiologic studies, there has been no age-matched normative data in Korean adults. The objective of this study is to evaluate the value of QST in diabetic polyneuropathy with normal range in Korean adults. Methods: The Computer Aided Sensory Examination IV 4,2 (WR Medical Electronics Co., Stillwater, Minnesota, U.S.A.), with 4,2,1 stepping algorithm was used to determine vibration and cold perception threshold in 70 normal controls and 19 patients with diabetic polyneuropathy aged from 21 to 79 years. The data were used to define age-matched upper and lower normal limits and normal range of side to side difference. We also evaluated the duration of diabetes, serum HbA1C level, and findings of nerve conduction study (NCS) and QST in patients with diabetic polyneuropathy. Results: In normal adults, sensory thresholds slightly increased with age, and a slight side-to-side difference was observed. The diagnostic sensitivity of QST was not higher than NCS in patients with diabetic polyneuropathy (36.8% vs. 42.1%, p=0.716), especially among elderly patients. Conclusions: QST might be used as a complementary test for NCS in the diagnosis of diabetic polyneuropathy. Although the QST is a simple method for the evaluation of peripheral nerve function, there are some limitations. Most of all, because the QST measuring is dependent on the subjective response of patients, the degree of concentration and cooperation of the patients can significantly affect the result. And thus, attention should be paid during the interpretation of QST results in patients with peripheral neuropathy.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.45-57
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• 2015

Objectives: This study aims to compare the physicochemical characteristics, toxicological data with Occupational Exposure Limits (OELs) of chemicals under the Occupational Safety and Health Act(OSHA) regulated by the Ministry of Employment and Labor of Korea. Methods: Information on chemicals which have OELs on physicochemical characteristics and toxicological data was collected using Material Safety Data Sheet(MSDS) from Korea Occupational Safety and Health Agency(KOSHA) and the Korea Information System for Chemical Safety Management(KISChem) in 2014. Statistical analyses including correlation and simple regression were performed to compare the OELs with chemical characteristics including molecular weight, boiling point, odor threshold, vapor pressure, vapor density, solubility and octanol-water partition coefficient(OWPC) and toxicological data such as median lethal dose($LD_{50}$) and median lethal concentration($LC_{50}$). Results: A total of 656 chemicals have OELs under OSHA in Korea. The numbers of chemicals which have eight-hour time weighted average(TWA) and short term exposure limits(STEL) are 618 and 190, respectively. TWA was significantly correlated with boiling point and STEL was only correlated with vapor pressure among physicochemical characteristics. Solubility and OWPC between "skin" and "no skin" substances which indicate skin penetration were not significantly different. Both $LD_{50}$ and $LC_{50}$ were correlated with TWA, while the $LC_{50}$ was not with STEL. As health indicators, health rating and Emergency Response Planning Guidelines(ERPG) rating as recommended by the National Fire Protection Association(NFPA) and American Industrial Hygiene Association(AIHA) were associated with OELs and reflect the chemical hazards. Conclusions: We found relationships between OEL and chemical information including physicochemical characteristics and toxicological data. The study has an important meaning for understanding present regulatory OELs.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.74-74
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• 2003

In present study, attempts were made to preserve abalone (Haliotis discus hannai) sperm in liquid form at low temperature, to evaluate the effect of various diluents in short-term storage on sperm, and cryopreservation procedures were optimized for the cryoprotectants as well as freezing rates, in terms of the motility and survival rate, and the ultrastructural changes of sperm after short-term storage and cryopreservation were observed. The abalone sperm reached maximum motility until about 4min after activation. The motility was constant for about 16min, after which it dropped gradually, and about 50min later all motility ceased. Threshold activation of sperm was found in 40% artificial seawater (ASW), and motility increased as the concentration of ASW increased. In Hanks balanced salt solution without calcium (Ca-Free HBSS, 300 and 400 mOsmol/kg) and 10%, 20%, and 30% ASW the sperm was immotile, and motility once again restored incompletely only in HBSS of 300 and 400 mOsmol/kg, 20% and 30% ASW after 100% ASW was added. Sperm motility was extended following 20 days of cold storage only in 70% and 100% ASW. A high motility index of 3.5-4.5 was observed for the first 8 days in 70% and 80% ASW. In other diluents sperm motility was constant less than 10 days, and the motility index was obviously lower than that of sperm in 70% and 100% ASW. After 20 days of cold storage survival rates of 10.2%-20.7% were obtained in ASW and 300 mOsmol/kg HBSS, and that in 400 HBSS (65.3%) was significantly higher than others. The constant period of sperm motility stored in 70% ASW was longer obviously than that in 100% ASW after 6 days of storage, and the time to maximum motility of sperm stored in 70% increased gradually, while the difference in which of sperm in 100% ASW was not significant. The sperm plunged into liquid nitrogen all died except that sperm using 15% glycerol as cryoprotectant restored 10.4% of motility. The highest motility index (3.4) was obtained with 5% glycerol and freezing procedure: $50^{\circ}C$/min from $20^{\circ}C$ to $-80^{\circ}C$.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.238-245
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• 2008

This study was carried out to investigate the effect of magnesium (Mg) concentrations in nutrient solution on growth of and nutrient uptake by 'Maehyang' strawberry. Tissue analysis based on dry weight and petiole sap were also conducted to determine the threshold level in plants when Mg deficiency disorders developed in strawberry plants. In the Mg deficient plants, the spotted yellowing or yellowing area developed on the interveinal area of mature leaves. The dark brown color also developed on the interveinal area of mature leaves with marginal browning or marginal necrosis. The response in dry weight production of 'Maehyang' strawberry to elevated Mg concentrations in nutrient solution was quadratic and the equation is y=6.84+1.7533x-$0.9278x^2$ $(R^2=0.1081^{***})$. But the Mg contents in tissue increased lineally with the equation of y=0.1764+0.1275x $(R^2=0.8307^{***})$. The trends of fresh weight production and Mg concentrations in petiole sap were also quadratic (y=24.127+7.3565x-$1.125x^2$, $R^2=0.2314^{^***}$) and linear (11.954+5.793x, $R^2=0.6869^{***}$), respectively. To prevent growth suppression, the Mg concentrations based on dry weight of above ground tissue and in petiole sap should be in the range of 0.30 to 0.65% and 19 to $40mg{\cdot}kg^{-1}$, respectively, fer the commercial production of 'Maehyang' strawberry.