• The Korean Journal of Mycology
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• v.9 no.1
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• pp.1-6
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• 1981

The effect of gamma irradiation on production and accumulation of aflatoxin on natural substrate (barley) by Aspergillus parasiticus NRRL 2999 has been studied in some detail. Gamma irradiation at five doses, 0, 50, 100, 200 and 400 Krad was applied to the grain either soon after moisture equilibration (3 days after inoculation) or 10 days later (13 days after inoculation). And the results were as in the followings. 1. Increase in moisture content from 17% to 25% greatly increased the aflatoxin concentration, especially at zero irradiation dose. 2. Prolongation of the incubation period prior to irradiation from 3 to 13 days resulted in greater accumulation of aflatoxin. 3. Two hundreds Krad applied 13 days after inoculation on barley stored at 25% moisture (100% RH) and $25^{\circ}C$ led to higher aflatoxin production than 100 Krad or even 50 Krad. 4. The relative proportion of the principal aflatoxins in relation to irradiation showed that aflatoxin G was elaborated at a significantly higher rate than aflatoxin B.

• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.88-94
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• 2001

Physical and chemical properties, the salt accumulation and leaching of salt by water of coal fly ash ball (ash ball) were evaluated in comparison with perlite and granule rockwool (rockwool). Bulk density, particle density, solid phase, and porosity of ash ball were 0.93 g.cm$^{-3}$ , 2.29 g.cm$^{-3}$ , 40.6%, 59.4%, respectively. The bulk density of ash ball was greater, while porosity was smaller, than that of perlite and rockwool. Saturation moisture capacity was 52% in ash ball, 71% in perlite, and 90% in rockwool. Water contents after drainage for 1 hr of ash ball, perlite, and rockwool were 21%, 27%, and 80%, respectively. Water content of small granules (3-5 mm) of ash ball was 5% greater than that of large (7-15 mm) grannules. The ash ball was a weak alkali substrate with pH 7.6, but not electric conductivity (EC), of the nutrient solution supplied to ash ball slightly increased. When the absorption of mineral ions to substrates were analyzed, ash ball and RW absorbed mainly PO￣$_4$. On tomato culture, salt accumulation in ash ball substrate was similar to that in perlite. Most of the salts in the ash balls were removed by submerging the substrate eight times in distilled water. It is concluded that water holding capacity of ash ball substrate was lo as compared to other substrates, but air permeability, and water diffusion was excellent, making control of medium water content easy.

• Journal of Forest and Environmental Science
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• v.29 no.1
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• pp.29-37
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• 2013

The study was carried out in two different forest types viz., Banj oak and Chir pine forests to assess the variation in forest species composition and soil properties along altitudinal gradients in the Garhwal Himalayas. The results of the study showed that between the forests soil moisture was higher in Banj oak forest because of closed canopy and dense forest compared to Chir pine forest. The sand particles were reported higher in Banj oak forest which might be due to the addition of organic matter favouring coarse structure of soil, helping in holding maximum water in soils. However in the Chir pine forest low amount of soil organic matter and presence of clayey soil, develops soil compactness which reduces the penetration of water resulting in high soil bulk density. The higher accumulation of litter and presence of moisture in Banj oak forest favours higher nutrient level of nitrogen, phosphorus and potassium compared to Chir pine forest. The soil organic carbon also reduced with increasing altitude at both gradients. While bulk density has reverse trend with soil organic carbon in both the forests at different peaks of same region. In Banj oak forest, the highest density and total basal cover was reported 1,100 tree $ha^{-1}$ and 58.86 $m^2\;ha^{-1}$ respectively. However, the highest values of density and total basal cover of Chir pine forest was 560 tree$ha^{-1}$ and 56.94 $m^2\;ha^{-1}$ respectively. The total density and basal cover of both the forests reduced with increasing altitude. The study concludes that Banj oak forest has better nutrient cycling ability, well developed foest floor and has a greater protective and productive features compared to the Chir pine forest which is without lower vegetation cover and having only pine litter accumulation which does not allow any other species to grow.

• Journal of the Korean Wood Science and Technology
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• v.48 no.6
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• pp.896-906
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• 2020

Wood deterioration experiments were carried out for 6 months in an intertidal zone of South Korea to monitor the changes in the chemical properties of two types of species, Korean red pine and sawtooth oak. The results of FT-IR spectra and XRD patterns have shown that the chemical properties of the wood did not change significantly during the 6-month burial period. However, the brightness of the surface decreased after burial; the value of the sawtooth oak sample was lower than that of the Korean red pine sample owing to an accumulation of inorganic compounds in cell lumen as observed by ICP analysis. Among the inorganic compounds, sodium and sulfur concentrations increased significantly over the burial period compared with the control. Further, the maximum moisture content decreased from 199% to 136% in the Korean red pine and 62% to 60% for the sawtooth oak. Nevertheless, the major chemical composition of both the wood species did not change significantly during the 6-month burial period, whereas, the crystallinity decreased with an increasing burial period owing to an accumulation of inorganic compounds in the lumen.

• Environmental Engineering Research
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• v.18 no.3
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• pp.151-156
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• 2013

Several soil properties were studied from three young created mitigation wetlands (<10 years old), which were hydrologically comparable in the Piedmont region of Virginia. The properties included soil organic matter (SOM), soil organic carbon (SOC), pH, gravimetric soil moisture, and bulk density ($D_b$). No significant differences were found in the soil properties between the wetlands, except SOM and SOC. SOM and SOC indicated a slight increase with wetland age; the increase was more evident with SOC. Only about a half of SOC variability found in the wetlands was explained by SOM ($R^2$ = 0.499, p < 0.05). The majority of the ratios of SOM to SOC for these silt-loam soils ranged from 2.0 to 3.5, which was higher than the 1.724 Van Bemmelen factor, commonly applied for the conversion of SOM into SOC in estimating the carbon storage or accumulation capacity of wetlands. The results may caution the use of the conversion factor, which may lead to an overestimation of carbon sequestration potentials of newly created wetlands. SOC, but not SOM, was also correlated to $D_b$, which indicates soil compaction typical of most created wetlands that might limit vegetation growth and biomass production, eventually affecting carbon accumulation in the created wetlands.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.25-32
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• 2003

Mongolia, a land-locked country in Central Asia, is located in the region of the highest degree of seasonal contrast on Earth. This paper presents sedimentologic and geomorphic data used to infer Holocene climate change in North-Central Mongolia. Correlation of data show that the climate was cold and dry before 10500 years BP. The post glacial warming occurred from 10500 to 8700 yr BP. The climate was characterized by becoming warmer and dry from 7300 to 6090 radiocarbon years. Between 6100 and 5500 years ago, conditions were hyper arid. Increased effective moisture balance but still arid conditions prevailed between 5500 and 3900 years ago. Since 3900 years ago, generally more humid conditions prevailed and originated varved sediment accumulation. Between about 2300 to 1300 years ago, greater than present day effective moisture balance. Since 1200 years ago climate was cooler and since 600 years ago becoming warmer.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.13 no.1
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• pp.237-252
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• 2000

Pressure sore is an area of ulceration and necrosis of the skin and underlying tissues usually occuring over the bony prominences of the body after prolonged or often repeated pressure. We reviewed and summarized the published articles and treatise on the treatment of pressure sore. The results were as follows : 1. Pressure sore occur due to prolonged or often repeated pressure. So it is better than decubitus ulcer that is called pressure sore. 2. The most common lesions of pressure sore are sacrum, ischial tuberosity, greater trochanter. 3. The cause of pressure sore are change of comprehension. urine, moisture, change of the ability of activity and exercise, shearing force. 4. The elements to influence on wound healing are collagen accumulation velocity, nutrition condition, Vitamine C, copper, iron. oxygen pressure, steroids, cell-toxic drug, radiation. 5. Non-operative treatments are managements of skin such as avoiding consistant pressure, dressing, preventing moisture, understanding patient and protecter, preventing spasm, improvement of systemic nutrition condition. 6. Operative treatements are debridement, suture, skin transplantation, muscle flap and musculaocutaneous flap surgery. Recently V-${\Gammer}$ advancement surgery in use of muscle and musculocutaneous flap is generally maded. 7. Complications of post-operation are wound rupture, infection, disappearance of transmitted skin, necrosis of flaps.

• Journal of Biosystems Engineering
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• v.10 no.2
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• pp.36-46
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• 1985

This study was intended to develop the mathematical model of the head-fed type threshing unit. As the first step, the physical model of the threshing phenomena was considered to consist of four separate processes as 1) detachment process of grains, 2) movement of grains between the cylinder and concave, 3) grain penetration through stems of bundle, and 4) grain passing through concave. The mathematical and computer models were developed based on the physical models. Threshing experiments were performed and determined the distribution of grain accumulation along the cylinder shaft by varying the moisture content of grains, feeding rate, and cylinder speed. It was found that the model developed coincided very well with the experimental results for the varied operational conditions. Greater concentration of grains passing through concave toward the thresher inlet was equally true for the model and experiment work for the threshing of grains with higher moisture content and with higher cylinder-speed. The model could be used for obtaining the optimized design or for optimizing the performance of the head-fed type threshing unit if term as to power requirement for threshing may be additionally included in the developed model.

• Journal of ILASS-Korea
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• v.12 no.1
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• pp.38-44
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• 2007

Since the Liquid Phase LPG injection (LPLI) system has Advantages in power generation and emission characteristics compared to the mixer-type fuel-supply system, a variety of studies regarding LPLi system has been conducted and its applications are made in automobile industry. However, the heat extraction due to the evaporation of liquid fuel, causes not only a post-accumulation of fuel but also an icing phenomenon which is a frost of moisture in the air around the nozzle tip. Since there exists a difficulty in the accurate control of air fuel ratio in both fuel supply systems, it can result in poor engine performance and a large amount of harmful emissions. This research examines the characteristics of icing phenomenon and develops anti-icing bushing to prevent an icing on the surface of the injection tip. It was found that n-butane, which has a relatively high boiling point ($-0.5^{\circ}C$), was a main species of post-accumulation. Also the results show that the post-accumulation problem was allevaited the utilization of a large inner to outer bore ratio and smooth surface roughness. In addition, an icing phenomenon and its formation process were found to be mainly affected by the humidity and the temperature of inlet air in an inlet duct. Also, it was observed that an icing phenomenon is lessened using aluminum bushing whose end coincides with the end of fuel injection tip in length.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1585-1591
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• 2001

The present study was conducted to evaluate the effect of early feed restriction on growth, fat accumulation and meat composition in unsexed broiler chickens. Five hundred 7-day old unsexed broiler chickens were distributed into ten treatment groups with 5 pens of 10 broilers each group. One group was fed ad libitum as the control group and other nine groups were fed 25% ad libitum for 3, 6 or 9 days, 50% ad libitum for 3, 6 or 9 days, and 75% ad libitum for 3, 6 or 9 days, respectively. Thereafter, they were fed ad libitum to 56 days of age. The present results showed that broilers showed compensatory growth when they were restrict-refed. Feed conversion ratio was significantly lower in broilers fed 25% ad libitum for 9 days (p<0.05). Triglyceride concentration of serum was significantly lower in restricted unsexed broilers (p <0.01), whereas cholesterol concentration was not significantly different. Abdominal fat was significantly lower in broilers fed 25% ad libitum for 9 days, 50% ad libitum for 3 days and 75% ad libitum for 6 or 9 days (p<0.05). Moisture and protein contents of meats were not significantly affected. Ash content of meat was significantly higher in restricted broilers. Fat content of meat was lower in broilers fed 25% ad libitum for 9 days, 75% ad libitum for 3 to 9 days. In conclusion, broilers showed compensatory growth when they were restrict-refed at an early age. In order to achieve the success of early feed restriction (namely reduce fat accumulation and improve feed conversion ratio with comparable body weight at market age), unsexed broilers should be fed at level of 25 ad libi=tum for 9 days starting at 7 days of age.