• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.322-335
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• 2003

Nutrient fluxes and sediment oxygen demands (SOD) were measured with intact sediment cores collected from three stations in the downstream of Nagdong River. The sediments were subjected to controlled oxic and hypoxic conditions and temperature gradients (from $10^{\circ}C$ to $30^{\circ}C$) of the overlying waters in laboratory batch system. The effect of temperature and labile layer thickness of the sediment on SOD were examined. $PO_4\;^{3-}$ and $NH_4\;^+$ fluxes were elevated above $20^{\circ}C$ and large mobilities were observed when they were coupled with a hypoxic and high-temperature condition. In the well oxygenated conditions, $PO_4\;^{3-}$ fluxes were negative or negligible but $NH_4\;^+$ fluxes ranged from 1.3 mg N $m^{-2}\;hr^{-1}$ to 2.3 $m^{-2}\;hr^{-1}$. Temperature quotients($Q_{10}$) of $PO_4\;^{3-}$ fluxes were 3.7 ${\sim}$ 7.3 ranges to have the most high values. $PO_4\;^{3-}$ and $NH_4\;^+$ fluxes had the logarithmic increase with temperature, while $NO_3\;^-$ was negatively absorbed to the sediment and linearly correlated with the temperature. $SiO_2$ fluxes showed no difference among oxic and hypoxic conditions and sediment texture. The nutrient fluxes would be closely correlated with pore water chemistry of sediments and activated by the top sediment layer composition such as labile organic matters or algal detritus. The ecological implications of the nutrient fluxes were discussed in terms of sources and sinks of nutrients coupled to algal productions in the Nagdong River.

• Food Science of Animal Resources
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• v.31 no.4
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• pp.570-579
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• 2011

This study created hamburger patties by substituting a portion of the meat with sea tangle (Laminaria japonica) powder and/or cooked rice to reduce fat and calories and to add the functional components of the sea tangle. Four types of experimental patties were prepared: Control, L, LI, and LII. L was the patty with sea tangle powder substituted for 2.5% of the meat and LI and LII were patties with cooked rice containing sea tangle powder substituted for 25 or 50% of the meat. In all experimental patties, moisture content increased and crude fat and cholesterol content decreased, pH increased, and malondialdehyde concentration decreased compared to those in the control. The substitutions made the color of the patties darker with dimmed redness and amplified yellowness. The substitutions also made the cooking loss weight and diameter of the patties lessen but that of thickness increased. In the sensory evaluation, symmetry and color of the patties improved significantly by substituting sea tangle powder and/or cooked rice for meat, and no adverse effect on preference for the experimental patties and hamburgers was observed. Therefore, substituting sea tangle and/or cooked rice for a portion of the meat could be used to develop healthier patties without any adverse influence on preference or sensory evaluation.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.603-609
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• 1992

To investigate the effect of polyethylene film packaging and $CO_2$ treatment on tomatoes during storage, the gas composition in film, weight loss, the changes of color, hardness and several components were measured. The concentrations of $CO_2$ and $O_2$ in film were changed rapidly in early stage, but it kept a constant level after 7 days of storage. In 0.06 mm polyethylene film, $CO_2$ and $O_2$ concentration was kept a level of $4{\sim}6%$ respectively. The increase in $C_2H_2$ concentration was delayed in thick and $CO_2$ treated film. The rate of weight loss was 4% in non-packed tomatoes, but it recorded about 1% in 0.06 mm polyethylene film. Titratable acidity, pH and soluble solids were changed slightly, but the obvious differents were not observed according to film thickness and $CO_2$ treatment. The value of tomatoes was increased but L and b values were not changed greatly during storage. These color changes were restricted by 0.06 mm film and $CO_2$ treatment. The firmness and content of ascorbic acid were reduced during storage but it restrained by $CO_2$ treatment and film packaging. Sugar of tomatoes were composed of glucose, fructose and a very small amount of sucrose, and they were changed little during storage.

• Journal of the Korean Arthroscopy Society
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• v.15 no.2
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• pp.83-91
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• 2011

Purpose: Microfracture has been used as a first-line treatment to repair articular cartilage defects. In this study, a new technique using an extracelluar matrix biomembrane to cover the cartilage lesions after microfracture was evaluated in terms of cartilage repairability and clinical outcome compared with conventional microfracture technique in a prospective randomized trial. Materials and Methods: A total of 53 patients (59 cases) without osteoarthritis who had focal full thickness articular cartilage lesions were randomly assigned in two group. Seventeen patients (17 cases) underwent conventional microfracture procedure (control group) and thirty-six patients (42 cases) received microfracture and placing biomembrane cover (ArtiFilm$^{TM}$) concomitantly (experimental group). Clinical assessment was done through 6 months postoperatively using the subjective International Knee Documentation Committee IKDC questionnaire, and visual analog scale (VAS) for pain and satisfaction. Magnetic resonance imaging (MRI) was performed at 6 months after the operation in all patients. Results: In clinical outcomes, the significant difference was observed between both groups in IKDC, but not in VAS for pain and for satisfaction (final outcomes of IKDC, p=0.001; VAS for pain, p=0.074; VAS for satisfaction, p=0.194). The MRI showed good to complete defect fill (67 to 100%) in 33 patients (78.6%) of experimental group and 4 patients (23.5%) of control group, respectively. In control group, 9 of 17 patients (52.9%) showed poor defect fill (less than 33%), whereas 5 (11.9%) in experimental group (p=0.001). Assessment of peripheral integration revealed no gap formation in 35 patients (83.3%) in experimental group and 6 patients (35.3%) in control group (p=0.001). No serious complications or adverse effects related to the biomembrane were found. Conclusion: Good short-term follow-up clinical results were obtained in the group whose cartilage defects in the knee joint were covered with biomembrane after the microfracture, with the MRI findings confirming the excellent regeneration of the defective cartilage area. This suggests that the surgery to cover the defective area with biomembrane (ArtiFilm$^{TM}$) after the microfracture procedure is a safe, more effective treatment to induce cartilage regeneration.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.4
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• pp.41-54
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• 2002

In this study, we have analyzed the effects of the membrane layer and the bragg reflector layers on the resonance characteristics through comparing the characteristics of the membrane type FBAR (Film Bulk Acoustic Wave Resonator) and the one type bragg reflector layers with those of the ideal FBAR with top and bottom electrode contacting air by using equivalent circuit technique. It is assumed that ZnO is used for piezoelectric film, $SiO_2$ are used for membrane layer and low acoustic impedance layer, W are used for the high acoustic reflector layer and Al is used for the electrode. Each layer is considered to have a acoustic propagation loss. ABCD parameters are picked out and input impedance is calculated by converting 1-port equivalent circuit to simplified equivalent circuit that ABCD parameters are picked out possible. From the variation of resonance frequency due to the change of thickness of electrode layers, reflector layers and membrane layer it is confirmed that membrane layer and the reflector layer just under the electrode have the greatest effect on the variation of resonance frequency. From the variation of resonance properties, K and electrical Q with the number of layers, K is not much affected by the number of layers but electrical Q increases with the number of layers when the number of layers is less than seven. The electrical Q is saturated when the number of layers is large than six. The electrical Q is dependent of mechanical Q of reflector layers and membrane layer. Both ladder filter and SCF (Stacked Crystal Filters) show higher insertion loss and out-of-band rejection with the increase of the number of resonators. The insertion loss decreases with the increase of the number of reflector layers but the bandwidth is not much affected by the number of reflector layers. Ladder Filter and SCF with membrane layer show the spurious response due to spurious resonance properties. Ladder filter shows better skirt-selectivity characteristics in bandwidth but SCF shows better characteristics in insertion loss.

• Korean Journal of Agricultural Science
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• v.9 no.1
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• pp.250-259
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• 1982

The Larch was known unsuitable species for the wood cement board owing to its some inhibitory substances. Therefore this research was carried out to evaluate the effect of pretreatments and chemical additives on the properties of woodflake cement board from Japanese larch (Larix leptolepis) grown in Korea. In order to improve the board qualities, the woodflakes were treated by cold water or dilute NaOH solutions(0.1, 0.5, and 2.0%), and also some chemicals($CaCl_2$, $Al_2Cl_3$ and $Na_2SiO_4$) added to the wood cement mixture. The results obtained are summarized as follow; 1. The wood cement boards from the woodflake treated with 0.1% NaOH showed remarkable higher bending strengths and internal bonding strengths than those from the flake pretreated with cold water. 2. The bending strengths showed over $60kg/cm^2$, i.e. the standard strength of JIS A-5417, with pretreatments of NaOH over 0.1% and additive of $CaCl_2$ 3.0%. The maximum strengths showed at about 0.5 of every additives. 3. Addition of $CaCl_2$ and $Al_2Cl_3$, in the case of pretreated wood with NaOH above 0.1%, had effects on increasing the internal bonding strengths of sample boards. 4. The thickness swellings became decreasing along with the increasing NaOH pretreatment concentntration. 5. The equilibrium conditions of the sample boards pretreated with NaOH over 0.1% and added with $Al_2Cl_3$ and $CaCl_2$ were maintained at 9.0~10.5% moisture contents. 6. The specific gravity of the samples showed close relationships with strength properties.

• Korean Journal of Plant Resources
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• v.29 no.5
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• pp.598-603
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• 2016

The aim of this study was to elucidate the influence of vigor of a bearing shoot in ‘Bluecrop’ Highbush Blueberry (Vaccinium corymbosum L.) on growth characteristics of shoots and fruits. Bearing shoots were classified with BS (bearing shoot) and BMB (bearing mother branch). The vigor of bearing shoots were divided into four arbitrary categories; A was thin (< 6.0 ㎜) BMB and short (< 10 ㎝) BS, B was thin BMB and long (≥ 10 ㎝) BS, C was thick (≥ 6 ㎜) BMB and short BS and D was thick BMB and long BS. Shoots from D were longer (6.5 ㎝) and thicker (1.70 ㎜) than those from the others. Shoots of D had more leaves (5.8 ea) than those of the others. Leaf area of D was larger (13.5 ㎠) than those of the others. The first harvest of D was one week faster than the others. Ratio of big berry (>14 ㎜) from the long BSs was higher (B : 41.7, D : 46.8%) than that from the short BSs. Soluble solid content of small berrys did not show any different according to vigor of bearing shoots, but soluble solid content of big berrys of the long BSs was higher (B : 16.2, D : 15.6°Bx) than those of the short BSs. The thickness of BMB did not affect ratio of fruit size and soluble soild content. The long BSs would be proper than the short BSs for bearing bigger fruits.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.448-453
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• 2014

Influences of shading and irrigation in summer hot pepper cultivation on the plant growth and mesophyll tissue were investigated. Hot pepper plants were exposed to three shade levels (0, $30{\pm}5$ and $80{\pm}5%$) and irrigated or non-irrigated in greenhouse condition. Plant height and leaf area were highest in 30% shading and stem diameter and fresh and dry weights were highest in no shading. Plant growth was better in rain shelters with irrigation than in those without irrigation. The numbers of hot pepper fruits in the beginning of harvest were 49 in rain shelters without irrigation and shading, 22 in those with irrigation and without shading, 5 in those without irrigation with 30% shading, and 1 in those with irrigation and 30% shading. However, 80% shading showed lowest flower number and flower abscission, resulting in no fruit set, regardless of irritation. This is because carbohydrate translocation from leaves to reproductive organs may be not enough for developing fruits due to the lack of sunlight. The yield of hot pepper tended to be higher in rain shelter with irrigation than in those without irrigation. In optical microscopy observation, the thickness and development of mesophyll tissues decreased as increasing the degree of shading but no effect of irrigation on mesophyll tissues was observed. When stomata were observed with scanning electron microscope (SEM), the shape of stomata was normal but tissues surrounding stomata were slightly wrinkled in plants grown under 30% shading. The large number of abnormal stomata and wrinkled leaves was observed among plants grown in rain shelters with 80% shading. In plants grown in rain shelters without irrigation, tissues surrounding stomata were wrinkled and 10-20% decrease in the number of stomata was observed. Therefore, in hot pepper cultivation in summer with high temperature, shading was not effective for fruit yield and mesophyll tissue development; if shading is unavoidable, high degree of shading is not advisable. Further studies are needed for appropriate cultivar selection and environment-control techniques in hot pepper cultivation in summer with high temperature.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.145-150
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• 2010

This study was conducted to evaluate effects of dietary Agariemycetes on egg quality and fecal noxious gas concentration in laying hens. A total of two hundred forty laying hens were randomly allocated to four treatments with five replicates of twelve chicks per pen. The experiment lasted 42 days with a 7-day adjustment period. Dietary treatments were as follows: 1) CON (basal diet), 2) A1 (basal diet + Agariemycetes 0.1%), 3) A3 (basal diet + Agariemycetes 0.3%) and 4) A5 (basal diet + Agariemycetes 0.5%). There was no significant difference in egg production and egg weight between CON and Agariemycetes treatments. During the second week of the experiment, eggshell breaking strength was higher in A3 and A5 treatments than that in CON treatment (P<0.05). Besides, eggshell breaking strength in P5 treatment was higher when compared with that in CON treatment (P<0.05) in the sixth week. During the second week of the experiment, eggshell thickness was higher in Agariemycetes treatments than CON treatment (P<0.05). Also, A5 treatment was higher than other treatments in the fourth week of the experiment (P<0.05). At the end of the second week, yolk color unit in A5 treatment was lower compared with CON treatment (P<0.05). During the fourth week of the experiment, CON treatment was higher than A3 treatment (P<0.05). During the second week of the experiment, Haugh unit in A3 treatment was greater than that in CON treatment (P<0.05). At the end of six weeks, Haugh unit in CON treatment was lower than other treatments (P<0.05). Fecal ammonia and hydrogen sulfide were increased in Agariemycetes treatments when compared with CON treatment (P<0.05). Compared with CON and A5 treatments, fecal mercaptans was higher than in other treatments in first of the experiment (P<0.05). In conclusion, this study indicated that the addition of Agariemycetes in the diet improved the egg quality and decreased the feacal noxious gas concentration in laying hens.

• Korean Journal of Poultry Science
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• v.41 no.4
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• pp.241-247
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• 2014

The objective of this experimental was to investigate the effect of dietary Cu-sulfate and Cu-soy proteinate on productive performance and small intestinal microflora. A total 1,000 Hy-Line Brown laying hens (35 weeks old) were randomly allotted to 1 of 5 dietary treatments: Control, Cu-sulfate 50, 100 (50, 100 ppm Cu supplementation as Cu-sulfate) and Cu-SP 50, 100 (50, 100 ppm Cu supplementation as Cu-soy proteinate). Each treatment was replicated 4 times with fifty birds per replication, housed in 2 birds cages. Fifty birds units were arranged according to randomized block design. Feeding trial lasted 5 weeks under 16L : 8D lighting regimen. Hen day egg production was significantly (P<0.05) higher in Cu treated groups than control. Feed intake, broken and shell-less egg production was not significantly influenced by treatment. Eggshell color, eggyolk color, haugh unit, and eggshell thickness were not significantly influenced by treatment. However, eggshell strength was significantly (P<0.05) greater in Cu treated groups than control. Concentration of copper of liver was significantly (P<0.05) greater in Cu treated groups than control. Concentration of zinc and iron of liver were not influenced by treatments. Population of Cl. perfrigens and Lactobacilli in the small intestinal content were significantly (P<0.05) influenced by treatments. Population of Cl. perfrigens decreased and that of Lactobacilli increased in the Cu supplement groups. In conclusion, dietary Cu sulfate and Cu-soy proteinate similarly improves egg production, eggshell strength, and favors intestinal microbial population of laying hens.