• Journal of The Korean Society of Grassland and Forage Science
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• v.34 no.4
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• pp.234-239
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• 2014

This experiment was conducted to evaluate the effect of seeding rates on the forage quality and productivity of direct-seeded whole crop rice at the experimental field of the Grassland and Forages Division, National Institute of Animal Science, RDA from 2007 to 2008. Whole crop rice variety, "Nokyang", developed by the National Institute of Crop Science, was directly seeded with four different seeding rates (30, 60, 90 and 120 kg/ha). There were no significant differences (p<0.05) found in emergence date, heading date, greenish and disease resistance based on the seeding rates. Plant height increased at higher seeding rates but the tiller number per plant decreased (p<0.05). The dry matter (DM) content showed no significant difference based on seeding rates (p<0.05) while the yield of fresh and dry matter increased with incremented seeding rates (p<0.05). Acid detergent fiber (ADF) content increased with higher seeding rates, but the neutral detergent fiber (NDF) content did not show a similar tendency. The total digestible nutrient (TDN) content was lowest with 120 kg/ha seeding rate. The grain ratio decreased at higher seeding rates. In economic analysis, the plot seeded at a rate of 60 kg/ha showed the highest income increment. Although high seeding rates increased the DM yield, a seeding rate of 60 kg/ha is recommended as the proper seeding rate for direct-seeded whole crop rice.

• Journal of Biosystems Engineering
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• v.36 no.2
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• pp.79-88
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• 2011

The purpose of this study was to analyze power requirement of an agricultural tractor by major field operations. First a survey was conducted to obtain annual usage ratio of agricultural tractor by field operation. Plowing, rotary tillage, and loader operations were selected as major field operations of agricultural tractor. Second, a power measurement system was constructed with strain-gauge sensors to measure torque of four driving axles and a PTO axle, speed sensors to measure rotational speed of the driving axles and an engine shaft, pressure sensors to measure pressure of hydraulic pumps, an I/O interface to acquire the sensor signals, and an embedded system to calculate power requirement. Third, the major field operations were experimented under fields with different soil conditions following planned operation paths. Power requirement was analyzed during the total operation period consisted of actual operation period (plowing, rotary tillage, and loader operations) and period before and after the actual operation (3-point hitch operating, forward and reverse driving, braking, and steering). Power requirement of tractor major components such as driving axle part, PTO part, main hydraulic part, and auxiliary hydraulic part were measured and calculated to determine usage ratio of agricultural tractor power. Results of averaged power requirement for actual field operation and total operation were 23.1 and 17.5 kW, 24.6 and 19.1 kW, and 14.9 and 8.9 kW, respectively, for plowing, rotary tillage, and loader operations. The results showed that rotary tillage required the greatest power among the operations. Averaged power requirement of driving axles, PTO axle, main hydraulic part, and auxiliary part during the actual field operation were 8.1, 7.8, 3.4, and 1.5 kW, respectively, and the total requirement power was about 70 % (20.8 kW) of the rated power. Averaged power requirement of driving axles, PTO axle, main hydraulic, and auxiliary hydraulic for the total operation period were 6.5, 6.0, 2.1, 0.9 kW, respectively, and total requirement power was about 52 % (15.5 kW) of the rated power. Driving axles required the greatest amount of power among the components.

• Journal of Biosystems Engineering
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• v.36 no.4
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• pp.243-251
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• 2011

Purpose of this study was to analyze power requirement of an agricultural tractor for baler operation. First, a power measurement system was developed and installed in a 75 kW agricultural tractor. Strain-gages with a telemetry system were used to measure torques of transmission and PTO input shafts. An engine tachometer was used to measure rotational speed of transmission and PTO input shafts. The measurement system also included pressure sensors to measure pressure of hydraulic pumps, an I/O interface to acquire the sensor signals, and an embedded system to determine power requirements. Second, field experiments were conducted at two PTO speed levels, and proportion of utilization ratio of rated engine power and power consumption of major parts (transmission input shaft, PTO input shaft, main hydraulic pump, and auxiliary hydraulic pump) were analyzed. Results of usage proportion of engine power for PTO speed level 1 and 2 were 4.1 and 2.2%, 31.5 and 16.3%, 49.6 and 59.7%, 14.4 and 20.8%, and 0.4 and 1.0%, respectively, for ratio of measured engine power to rated engine power of less than 25%, 25 ~ 50%, 50 ~ 75%, 75 ~ 100%, and greater than 100%. The results showed that the usage proportion increased in the range with the ratio of power requirement to rated engine power of over than 50% when the PTO gear was shifted from P1 to P2. Averaged engine power requirement for baling operation, tying and discharging operation, and total operation were 43.3, 37.3, and 42.0 kW and 49.0, 37.0, and 47.4 kW, respectively, for PTO speed level 1 and 2. Paired t-test showed significant difference in power consumption of engine, transmission input shaft, and PTO input shaft for different PTO speed levels. Therefore, the power consumption of engine for baler operation increased when the PTO gear was shifted from P1 to P2. It was indicated that the power requirement of tractor was affected by the PTO rotational speed for baler operation.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.664-671
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• 2013

The objective of this study was to investigate the effect of high pressure treatment and type of binding agents on the quality characteristics of restructured pork. For binding agents, 2% (w/w) isolated soy protein (SP), 0.5% (w/w) wheat flour (WF) and 0.5% (w/w) ${\kappa}$-carrageenan (KC) were incorporated into meat batter with or without 0.5% (w/w) glucono-${\delta}$-lactone (GdL). The restructured pork was pressurized at varying pressure levels (0.1-450 MPa) for 3 min under ambient temperature and thermal treated at $75^{\circ}C$ for 30 min. As quality parameters of restructured pork, pH, water binding properties, instrumental color and texture profile analysis were determined and compared with control (C, no binder). For type of binders, SP exhibited the best water binding properties, however, the impact on textural properties were lesser than KC and WF. The addition of GdL decreased the pH of restructured pork down to 0.4 unit, while high pressure processing prevented the moisture loss caused from pH decrease by GdL. In particular, meat restructuring efficiency of SP as a binder improved under the presence of GdL. Therefore, the present study demonstrated the potential advantages of low amount of GdL (0.5%, w/w) combined with protein based binder (SP) and high pressure processing in restructuring meat particles.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.515-520
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• 2007

To establish the roasting conditions of dandelion leaves for the manufacture of processed foods such as beverages and tea, we investigated the physicochemical and sensory characteristics of dandelion leaves and their hot water extracts by roasting treatment. As the number of roasting times increased, the free sugar content of the roasted dandelion leaves decreased, and in particular, free amino acid and total polyphenol content decreased greatly after only 1 roasting treatment. The amino nitrogen and total polyphenol contents of the roasted dandelion leaf hot water extracts also decreased greatly, and their L-, a-, and b-values showed much lower values than those of the raw leaf extracts. However, a greater amount of reducing sugars was extracted in the roasted leaves than in the raw leaves, suggesting that the roasting process allows for easier extraction of the compounds in dandelion leaves. Five sensory characteristics, including astringent taste, bitter taste, peen flavor, burnt taste, and sweet odor, were deduced through quantitative descriptive analysis of the hot water extracts. Among them, astringent taste, bitter taste, and green flavor showed significant differences between roasting treatments. The sensory evaluation results show that as the number of roasting times increased, the palatability of the hot water extracts increased greatly, in terms of color and taste.

• Korean Journal of Poultry Science
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• v.36 no.4
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• pp.323-328
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• 2009

In order to determine the origin and genetic diversity among chicken breeds, mitochondrial (mt) DNA D-loop sequences have been widely used. In this study, 41 individuals from four breeds (Korean native chicken (Black and Brown) and two imported breeds, Rhode Island Red and Cornish) were used for identifying genetic relationships with other chicken breeds. We obtained ten haplotypes and the highest number of haplotype was represented by eight individuals each from haplotype 1 and haplotype 2. Neighbor-joining phylogenetic tree indicates that the black and brown Korean native chicken breeds were mixed in haplotype 2 and they were closely related with the red jungle fowl (Gallus gallus). We also investigated whether the D-loop hypervariable region in chicken mtDNA can be used for the breed identification marker. The results indicated that the combination of the SNPs in the D-loop region can be possibly used for the breed discriminating markers. The results obtained in this study can be used for designing proper breeding and conservation strategies for Korean native chicken, as well as development of breed identification markers.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.115-126
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• 2017

There is an increasing concern over arsenic (As) contamination in rice. This study was conducted to develope a prediction model for As uptake by rice based on the physico-chemical properties of soil. Soil and brown rice samples were collected from 46 sites in paddy fields near three different areas of closed mines and industrial complexes. Total As concentration, soil pH, Al oxide, available phosphorus (avail-P), organic matter (OM) content, and clay content in the soil samples were determined. Also, 1.0 N HCl, 1.0 M $NH_4NO_3$, 0.01 M $Ca(NO_3)_2$, and Mehlich 3 extractable-As in the soils were measured as phytoavailable As concentration in soil. Total As concentration in brown rice samples was also determined. Relationships among As concentrations in brown rice, total As concentrations in soils, and selected soil properties were as follows: As concentration in brown rice was negatively correlated with soil pH value, where as it was positively correlated with Al oxide concentration, avail-P concentration, and OM content in soil. In addition, the concentration of As in brown rice was statistically correlated only with 1.0 N HCl-extractable As in soil. Also, using multiple stepwise regression analysis, a modelling equation was created to predict As concentration in brown rice as affected by selected soil properties including soil As concentration. Prediction of As uptake by rice was delineated by the model [As in brown rice = 0.352 + $0.00109^*$ HCl extractable As in soil + $0.00002^*$ Al oxide + $0.0097^*$ OM + $0.00061^*$ avail-P - $0.0332^*$ soil pH] ($R=0.714^{***}$). The concentrations of As in brown rice estimated by the modelling equation were statistically acceptable because normalized mean error (NME) and normalized root mean square error (NRMSE) values were -0.055 and 0.2229, respectively, when compared with measured As concentration in the plant.

• Journal of Veterinary Clinics
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• v.27 no.2
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• pp.147-153
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• 2010

Bio-integration of cartilage grafts with subchondral bone is a significant clinical challenge. To date, the use of demineralized bone matrix (DBM) has been one of the most effective strategies for bone cell proliferation in vivo. Here, we investigated whether coculture of chondrocytes and DBM could serve as a single-platform system containing all the essential elements for purposive bone and cartilage induction. The aim of this study was to evaluate and compare the phenotype and proliferation of bovine chondrocytes cocultured with DBM in two different culture systems, pellet and alginate bead culture. In alginate bead culture, we observed an increase in chondrocyte number and formation of cell clusters. Typical chondrocytic phenotype was maintained for entire eight weeks. Histological analysis showed that chondrocytes maintained a typical round, plump morphology and there was a gradual increase in lacunae. Both coculture systems yielded an expanded cell population as compared to the controls (chondrocytes alone). The production of glycosaminoglycans was also increased in the coculture systems as compared to controls.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.2
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• pp.103-111
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• 2011

Purpose: Choukroun's platelet-rich-fibrin (PRF) is composed of platelets, white blood cells and fibrin matrix. It does not induce enough bone formation by itself but it can improve bone formation with calcium. Silk fibroin does not cause inflammatory reactions because it is bio-compatible and degradable. The purpose of this study was to exam the bone formation when a combination of Choukroun's PRF and silk fibroin was used. Methods: In this study, cell reactions to silk powder with differing molecular weights was first tested to select the appropriate silk powder. Then we applied these bone graft materials on defects of skull and in a peri-implant bony defect model in New Zealand rabbits. The results between the experimental and control s (non-grafted) group were analyzed. Results: The small sized silk fibroin powder showed increased cellular proliferation for bone-regeneration. There was no statistically significant difference between the experimental group and the control group at 6 weeks, but more new bone formation was observed in the combination graft group at 12 weeks (P<0.05). And in the dental implant model, the combination bone graft group showed much improved torque test results, which was statistically significant. Histomorphometric analysis showed more regenerated cortical bone and a higher mean bone to implant in the experimental group. Both were statistically significant. Conclusion: The combination graft of Choukroun's platelet-rich-fibrin (PRF) and silk fibroin powder can successfully restore the bony defects in a skull defected model and a peri-implant bony defects model.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.31 no.5
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• pp.440-453
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• 2005

Objectives : To develop a bioactive membrane for guided bone regeneration (GBR), the biocompatibility and bone regenerating capacity of the cellulose membrane obtained from the Ascidians squirt skin were evaluated. Materials and methods : After processing the pure cellulose membrane from the squirt skin, the morphological study, amino acid analysis and the immunoreactivity of the cellulose membrane were tested. Total eighteen male Spraque-Dawley rats (12 weeks, weighing 250 to 300g) were divided into two control (n=8) and another two experimental groups (n=10). In the first experimental group (n=5), the cellulose membrane was applicated to the 8.0 mm sized calvarial bone defect and the same sized defect was left without cellulose membrane in the first control group (n=4). In the another experimental group (n=5), the cellulose membrane was applicated to the same sized calvarial bone defect after femoral bone graft and the same sized defect with bone graft was left without cellulose membrane in the another control group (n=4). Each group was sacrificed after 6 weeks, the histological study with H&E and Masson trichrome stain was done, and immunohistochemical stainings of angiogenin and VEGF were also carried out. Results : The squirt skin cellulose showed the bio-inductive effect on the bone and mesenchymal tissues in the periosteum of rat calvarial bone. This phenomenon was found only in the inner surface of the cellulose membrane after 6 weeks contrast to the outer surface. Bone defect covered with the bioactive cellulose membrane showed significantly greater bone formation compared with control groups. Mesenchymal cells beneath the inner surface of the bioactive cellulose membrane were positive to the angiogenin and VEGF antibodies. Conclusion : We suppose that there still remains extremely little amount of peptide fragment derived from the basement membrane matrix proteins of squirt skin, which is a kind of anchoring protein composed of glycocalyx. This composition could prevent the adverse immunological hypersensitivity and also induce bioactive properties of cellulose membrane. These properties induced the effective angiogenesis with rapid osteogenesis beneath the inner surface of cellulose membrane, and so the possibilities of clinical application in dental field as a GBR material will be able to be suggested.