• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.58 no.3
• /
• pp.292-300
• /
• 2013

In this study, we examine the palatability and physicochemical properties of rice in the year, when there was 10% increase in yield compared to normal year due to daily temperature range and sunshine hours. The results of the analysis of rice yield over the last 20 years (1993-2012) showed 10% difference between the yield in 2000, which was normal, and that in 2001. With regard to the crop weather condition during the ripening period in 2001 compared to 2000, the daily range and sunshine hours were higher, but the mean temperature was similar. The rice yield in 2001 was 9.8% higher than that in 2000 due to the increased number of spikelets per panicles and ratio of ripened grain. In terms of chemical traits, protein, Mg, and K contents decreased in 2001 compared to 2000, but amylose content increased. Trough and final viscosity assessed with a Rapid Visco Analyser were significantly higher in 2001 than 2000. The quality of cooked rice was measured through the Toyo Mido Meter Glossiness Value (TGV) instead of a palatability score because a sensory test produces relative comparison values rather than absolute values. The correlation coefficients between the sensory evaluation parameters and the TGV in several rice materials harvested in two years showed a highly significant positive correlation ($r=0.81^{**}-0.89^{**}$, n=27-47). TGV was also significantly higher in 2001 than in 2000. The results suggested that the palatability of cooked rice was good in 2001 with about 10% increase in rice yield compared to normal year in 2000 due to daily temperature range and sunshine hours.

• Economic and Environmental Geology
• /
• v.25 no.3
• /
• pp.259-273
• /
• 1992

The Seongsan mine is one of the largest dickite deposits in the southwestern part of the Korean Peninsula. The main constithent minerals of the ore are dickite and quartz with accessory alunite, kaolinite and sericite. The geology around the Seongsan mine consists mainly of the late Cretaceous felsic volcanic rocks. In the studied area, these rocks make a synclinal structure with an axis of E-W direction plunging to the east. Most of the felsic volcanic rocks have undergone extensive hydrothermal alteration. The hydrothermally altered rocks can be classified into the following zones: Dickite, Dickite-Quartz, Quartz, Sericite, Albite and Chlorite zones, from the center to the margin of the alteration mass. Such zonal arrangement of altered rocks suggests that the country rocks, most of which are upper part of the rhyolite and welded tuff, were altered by strongly acid hydrothermal solutions. It is reasonable to consider that initial gas and solution containing $H_2S$ and other compounds were oxidized near the surface, and formed hydrothermal sulfuric acid solutions. The mineralogical and chemical changes of the altered rocks were investigated using various methods, and chemical composition of fifty-six samples of the altered rocks were obtained by wet chemical analysis and X.R.F. methods. On the basis of these analyses, it was found that some components such as $SiO_2$, $Al_2O_3$, $Fe_2O_3$, CaO, MgO, $K_2O$, $Na_2O$ and $TiO_2$ were mobilized considerably from the original rocks. The formation temperature of the deposits was estimated as higher than $200^{\circ}C$ from fluid inclusion study of samples taken from the Quartz zone. On the basis of the chemical composition data on rocks and minerals and estimated temperatures, the hydrothermal solutions responsible for the formation of the Seongsan dickite deposits were estimated to have the composition: $m_{K^+}=0.003$, $m_{Na^+}=0.097$, $m_{SiO_2(aq.)}=0.008$ and pH=5.0, here "m" represents the molality (mole/kg $H_2O$).

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.21 no.4
• /
• pp.327-336
• /
• 2019

Soybean is one of the most important crops of which the grains contain high protein content and has been consumed in various forms of food. Soybean plants are generally cultivated on the field and their yield and quality are strongly affected by climate change. Recently, the abnormal climate conditions, including heat wave and heavy rainfall, frequently occurs which would increase the risk of the farm management. The real-time assessment techniques for quality and growth of soybean would reduce the losses of the crop in terms of quantity and quality. The objective of this work was to develop a simple model to estimate the growth of soybean plant using a multispectral sensor mounted on a rotor-wing unmanned aerial vehicle(UAV). The soybean growth model was developed by using simple linear regression analysis with three phenotypic data (fresh weight, dry weight, leaf area index) and two types of vegetation indices (VIs). It was found that the accuracy and precision of LAI model using GNDVI (R²= 0.789, RMSE=0.73 ㎡/㎡, RE=34.91%) was greater than those of the model using NDVI (R²= 0.587, RMSE=1.01 ㎡/㎡, RE=48.98%). The accuracy and precision based on the simple ratio indices were better than those based on the normalized vegetation indices, such as RRVI (R²= 0.760, RMSE=0.78 ㎡/㎡, RE=37.26%) and GRVI (R²= 0.828, RMSE=0.66 ㎡/㎡, RE=31.59%). The outcome of this study could aid the production of soybeans with high and uniform quality when a variable rate fertilization system is introduced to cope with the adverse climate conditions.

• Korean Journal of Environmental Agriculture
• /
• v.31 no.1
• /
• pp.37-44
• /
• 2012

BACKGROUND: Many edible mushrooms are known to accumulate high levels of heavy metals. This research was focused on health risk assessment to investigate the mushrooms in Korea, arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) contaminations in edible mushrooms in cultivated areas were investigated, and health risk was assessed through dietary intake of mushrooms. METHODS AND RESULTS: The heavy metals in mushrooms were analyzed by ICP/MS after acid digestion. Probabilistic health risk were estimated by Monte-Carlo simulation techniques. The average contents of As, Cd, Pb, and Hg were $0.035{\pm}0.042$ mg/kg, $0.017{\pm}0.020$ mg/kg, $0.043{\pm}0.013$ mg/kg, and $0.004{\pm}0.004$ mg/kg, respectively. The results showed that contents of Cd and Pb did not exceed maximum residual levels established by European Uion regulation (Cd 0.20 mg/kg and Pb 0.30 mg/kg). For health risk assessment, estimated intakes in all age populations did not exceed the provisional tolerable daily intake of As and Hg, provisional tolerable monthly intake of Cd, provisional tolerable weekly intake of Pb. The Hazard Index (HI) were ranged from $0.03{\times}10^{-4}{\sim}0.01{\times}10^{-3}$ for As, $0.02{\times}10^{-3}{\sim}0.81{\times}10^{-3}$ for Cd, $0.06{\times}10^{-3}{\sim}0.38{\times}10^{-3}$ for Pb, and $0.08{\times}10^{-4}{\sim}0.14{\times}10^{-3}$ for Hg at general population. CONCLUSION: The HI from the ratio analysis between daily exposure and safety level values was less than 1.0. This results demonstrated that human exposure to heavy metals through dietary intake of mushrooms might not cause adverse effect.

• Applied Microscopy
• /
• v.40 no.2
• /
• pp.73-80
• /
• 2010

Liver regeneration is a result of highly coordinated proliferation of hepatocytes and nonparenchymal liver cells. Partial hepatectomy (PH) is the most often used stimulus to study liver regeneration because, compared with other methods that use hepatic toxins, it is not associated with the tissue injury and inflammation, and the initiation of the regenerative stimulus is precisely defined. Granulocyte macrophage-colony stimulating factor (GM-CSF), which is a cytokine able to regulate the proliferation and differentiation of epithelial cells, was first identified as the most potent mitogen for bone marrow. Particularly, rrhGM-CSF, which is highly glycosylated and sustained longer than any other types of GM-CSF in the blood circulation, was specifically produced from rice cell culture. In this experiment, effects of rrhGM-CSF administration were evaluated in the regenerating liver after 78% PH of rats. Morphological changes induced by PH were characterized by destroyed hepatocyte plate around the central vein and enlarged nuclear cytoplasmic ratio and increased hepatocytes with two nuclei. And then, proliferation of liver cells (parenchymal and nonparenchymal) and rearrangement of plates and lobules seemed to be carried out during liver regeneration. These alterations in the experimental group preceded those of the control. Since proliferating cell nuclear antigen (PCNA) is known to be a nuclear protein maximally elevated in the S phase of proliferating cells, the protein was used as a marker of liver regeneration after PH in rats. PCNA levels by western blot analysis and immunohistology were compared between the two groups. PCNA protein expression of two groups at 12 hr and 24 hr after injury showed similar pattern. The protein expression showed the peak at 3 days in both groups, however, the protein level of the experimental group was higher than that of the control. On immunohistochemical observations, the reaction product of PCNA was localized at the nuclei of proliferating cells and the positive reaction in experimental group at 3 days was clearly stronger than that in control group. The results by Western blotting and immunohistology for PCNA showed similar pattern in terms of the protein levels. In conclusion, rrhGM-CSF administration during liver regeneration after 78% PH accelerated breakdown and restoration of the hepatic plate and expression of PCNA. These results suggest that rrhGM-CSF might play an important role during liver regeneration in rats.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.28 no.2
• /
• pp.139-154
• /
• 2008

The nearly 75% of animal feed materials used for livestock production are imported every year in Korea. Most of imported feed ingredients are concentrated feeds such as com, wheat, soybean, soybean meal, etc. and they are used as the source materials for the production of assorted feed. The imported concentrated feeds are high in nitrogen and phosphorus. Therefore, the consistent import of feed ingredients may cause an increase of nutrient deposit in our agricultural ecosystem. In the current review, it was discussed with the situation of the feed importation and its nutritional composition to evaluate the nutrient load by the imported feeds onto agricultural ecosystem. The nutrient load caused by imported feeds in agricultural environment was compared with the nutrient demand for crop production. The amounts of N, $P_2O_5\;and\;K_2O$ introduced by the imported fteds in Korea were 371, 140 and 143 Ktons. And, the N, $P_2O_5\;and\;K_2O$ loads excreted from imported feeds in livestock were 148, 84 and 86 Ktons of N, $P_2O_5\;and\;K_2O$ and These nutrient loads by the imported feeds are at the percentage of N 52%, $P_2O_5$ 52% and $K_2O$ 42% in the comparison of total nutrient amounts excreted from livestock animals in Korea. The 82.3% of nutrients excreted from livestock was recycled to crop land as compost and liquid fertilizer, and the others were discharged to river after water treatment processing or disposed to ocean. Also, passing through the recycling process far the production of compost and liquid fertilizer, the amount of nutrients was reduced by the ammonia vaporization of livestock feces and urine. Accordingly, N 81, $P_2O_5$ 74 and $K_2O$ 76 Ktons in the nutrients excreted from livestock were estimated to be utilized in the crop land. Consequently, it was estimated that 44, 48 and 69 Ktons of N, $P_2O_5\;and\;K_2O$ were taken up with crops in the consideration of the ratio of mineralization, and the amounts of leached or deposited N, $P_2O_5\;and\;K_2O$ in crop land were estimated to be 37, 27 and 7 Ktons, respectively. It is estimated that 12%, 34% and 48% of N, $P_2O_5\;and\;K_2O$ introduced by the imported feeds were used by crops, and 10%, 34% and 5% of N, $P_2O_5\;and\;K_2O$ were leached or deposited in agricultural ecosystem. Therefore, considering the leached and deposited amounts of N, $P_2O_5\;and\;K_2O$ originated from the imported feed ingredients, the consistent import of feeds may gradually increase the nutrient load onto agricultural ecosystem.

• Applied Chemistry for Engineering
• /
• v.28 no.1
• /
• pp.101-111
• /
• 2017

Mineral carbonation is a technology in which carbonates are synthesized from minerals including serpentine and olivine, and industrial wastes such as slag and cement, of which all contain calcium or magnesium when reacted with carbon dioxide. This study aims to develop the mineral carbonation technology for commercialization, which can reduce environmental burden and process cost through the reduction of carbon dioxide using steel slag and the slag reuse after calcium extraction. Calcium extraction was conducted using NH4Cl solution for air-cooled slag and convert slag, and ${\geq}98%$ purity calcium carbonate was synthesized by reaction with calcium-extracted solution and carbon dioxide. And we conducted experimentally to minimize the quantity of by-product, the slag residue after calcium extraction, which has occupied large amount of weight ratio (about 80-90%) at the point of mineral carbonation process using slag. The slag residue was used to replace silica sand in the manufacture of cement panel, and physical properties including compressive strength and flexible strength of panel using the slag residue and normal cement panel, respectively, were analyzed. The calcium concentration in extraction solution was analyzed by inductively coupled plasma optical emission spectrometer (ICP-OES). Field-emission scanning electron microscope (FE-SEM) was also used to identify the surface morphology of calcium carbonate, and XRD was used to analyze the crystallinity and the quantitative analysis of calcium carbonate. In addition, the cement panel evaluation was carried out according to KS L ISO 679, and the compressive strength and flexural strength of the panels were measured.

• Korean Journal of Ecology and Environment
• /
• v.39 no.4 s.118
• /
• pp.498-507
• /
• 2006

The main objective of present study was to evaluate how seasonal rainfall influenced natural habitat conditions of 10 metric habitat variables along with ionic conditions and suspended solids in the Woopo Wetland during August 2002-July 2003. Largest spatial variabilities in total suspended solids (TSS) occurred during the summer monsoon and the inorganic suspended solids (ISS), expressed as a inorganic proportion of total solids, showed linearly increasing trend from the upstream to downstream. This phenomenon was mainly attributed to counter flow of turbid water from the main Nakdong-River. During the flooding, ISS : TSS ratio showed large increases (92%) in the downstream than the upstream (43%). For this reason, transparency declined (mean=0.13 m, range=0.08-0.21 m) largely in the downstream reach and thus, chlorophyll-a concentration showed low values (range: $4.2-8.6\;{\mu}g\;L^{-1}$), indicating a direct influence on primary productivity or algal growth by inorganic turbidity. In the 2nd survey, ISS averaged 4.0 mg $L^{-1}$ (3.3-4.8 mg $L^{-1}$), thus the ISS decreased by 14 fold, compared to the ISS in the 1st survey during the flooding, while organic suspended solids (OSS) values were greater than those of ISS, indicating a dominance of organic solids. This condition was similar to solid contents in the 3rd survey, but showed a large difference compared to the 4th survey during the growing season. Habitat health assessments, based on 10 metric habitat variables, showed that QHEI values were greatest in the growing season (May) than any other seasons and largest spatial variations occurred in the 2nd survey. Overall, dataset suggest that seasonal episodic flooding during the monsoon may largely contribute nutrient cycling and sediment contents in the Woopo Wetland and Topyung Stream.

• Advances in pediatric surgery
• /
• v.6 no.2
• /
• pp.106-123
• /
• 2000

The purpose of the survey was to clarify the clinical features and management of the anorectal malformations (ARM) in Korea. Twenty-seven members of the Korean Association of Pediatric Surgeons were surveyed. The members completed a case registration form for each patient during the two years period of 1996-1997, and a questionnaire that contained their management preferences for primary and complicated patients. Twenty-four members of the 22 institutions registered 295 cases of the ARM, and 27 out of 34 members (77.1 %) responded to the questionnaire. The patients were classified by the Wingspread classification of ARM(1984). The case registration form was a modification of Wingspread workshop for the postoperative assessment and case registration. The male to female ratio was 1.7 : 1. The average number of patients per surgeon was 6.1 cases per year. Prematurity(< 36 weeks) was present in 1.9 % of cases and low birth weight (< 2.6 Kg) in 12.1 %. Among 187 male patients, 62 were high(H) type, 29 intermediate(l) type, 88 low(L), and 8 unclassified. In female, there were 2 cases of cloacal anomalies(C), 4 H type, 30 I type, 66 L type and 6 unclass ified. For male, 87.9 % of H and I type were operated by the Pena procedure, but only 7.9 % in L types. In female, all of C, H and I types, and 40.9 % of L type were done by the Pena procedure. One case expired (MR; 0.003%) as a result of surgical complication. Over-all complication rate was 12.5 %. Among 6 cases of reoperation, 4 were failed Pena procedures. Among 140 colostomies sigmoid colon was utilized in 75.7%, and loop colostomy was commonly used. Ten surgeons prefered primary maturation of the stoma. In conclusion, posterior sagittal anorectoplasty is popular for high types of ARM in this country, but considerable number of patients are still suffering from failed operations. For better understanding and analysis, necessity of prospective study by new classification was discussed.

• Tuberculosis and Respiratory Diseases
• /
• v.50 no.2
• /
• pp.236-244
• /
• 2001

Background : Most current research using prognostic scoring systems in critically ill patients have focused on prediction using the first intensive care unit (ICU) day data or daily updated data. Usually the mean ICU length of stay in Korea is longer than in the western world. Consequently, a more cost-effective and practical prognostic parameter is required. The principal aim of this study was to assess the prognostic value of the seventh day(7th day : the average mean ICU length of stay) APACHE III score in a medical intensive care unit. Methods : 241 medical ICU patients from July 1997 to April 1998 were enrolled. The 1st and 7th scores were measured by using the APACHE III scoring system and compared between survivors and non-survivors. Logistic regression analysis was performed to determine the relationship between the $1^{st}$ and $7^{th}$ APACHE III scores and the mortality risk. Results : 1 )The mean length of stay in the ICU was $10.3{\pm}13.8$ days. 2)The mean $1^{st}$ and $7^{th}$ day APACHE III scores were $59.7{\pm}30.9$ and $37.9{\pm}27.7$. 3) The mean $1^{st}$ day APACHE III score was significantly lower in survivors than in non- survivors($49.9{\pm}23.8$ vs $86.3{\pm}32.3$, P<0.0001). 4)The mean $7^{th}$ day APACHE III score was significantly lower in survivors than in non- survivors($30.1{\pm}18.5$ vs $80.1{\pm}30.4$, P<0.0001). 5)The odds ratios among the $1^{st}$ and $7^{th}$ day APACHE III scores and the mortality rate were 1.0507 and 1.0779 respectively. Conclusion : These results suggest that the seventh day APACHE III score is as useful in predicting the outcome as is such like the first day APACHE III score. Therefore, in comparison to the daily APACHE III score, measuring the $1^{st}$ and $7^{th}$ day APACHE III scores are also useful for predicting the prognosis of critically ill patients in terms of cost-effectiveness. It is suggested that the $7^{th}$ day APACHE III score is useful for predicting the clinical outcome.