• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.309-314
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• 2009

Incidence of rice stripe disease, caused by Rice stripe tenuivirus (RSV), was surveyed during 2002 to 2004. The incidence area and ratio of diseased fields were decreased gradually during those period. Rate of diseased plants were 45.8%, 45.0% and 43.7% in the susceptible cultivars Chucheong, Saechucheong and Ilpum, respectively. However, the rate was 4.4% in resistant cultivar Hwaseong. In addition, breakdown rate was also significantly high in the susceptible cultivars in Chucheong, Saechucheong and Ilpum showing 33.6, 33.2 and 31.9%, respectively. In Hwaseong, the breakdown rate was 0.8%. Collection efficiency was compared between two insect vector collection methods. Insect-sucking machine method was much more efficient than sweeping net method in collecting small brown plant hopper (SBPH). According to the survey of the population density of the insect vector during 2002 to 2004, the national average population density was gradually decreased year by year, 3.6, 2.3, and 1.3%, respectively. This result was significantly related with the decrease of the incidence of rice stripe disease. Control efficiency of rice stripe disease by treating several seedling box and water surface with insecticides against SBPH resulted that imidacloprid GR, Fipronil FG, Clothianidin+Probenazole GR and Thiamethoxam GR showed over 80% of control efficiency at 28 days after treatment at the early stage in nursery.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.264-271
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• 2002

Nitrogen releasing characteristics of polymer-coated urea(PCU) that made acrylic synthetic resins were studied in incubated soil, water and paddy soil. Also, their correlations and degradation patterns of coating material were tested. Releasing rate of nitrogen from PCU decreased with increasing coating rate. N001(coating rate 8.5%) and N003(coasting rater 6.3%) were low releasing amount at the early stage, whereas N005(coating rate 4.8%) was released over 80% within 20 days. Relationship of the releasing rate between incubated soil($25^{\circ}C$) and paddy soil could be described as follows : $Y=-0.0011X^2+2.2931X-50.264(R^2=0.9884)$ for N001, $Y=-0.0016X^2+1.1587X+5.5064(R^2=0.9805)$ for N003 and $Y=-0.03X^2+6.499X-243.22(R^2=0.9422)$ for N005, respectively (Y: release rate at field condition, X: experiment period). Relationship of the releasing rate between incubated water($30^{\circ}C$) and paddy soil can be described as follows : $Y=0.0011X^2+2.2601X-25.329(R^2=0.9884)$ for N001, $Y=-0.0306X^2+4.4994X-76.307(R^2=0.955)$ for N003 and $Y=-0.0164X^2+3.7764X-108.22(R^2=0.9422)$ for N005. After 150 days, coating materials of N001, N003, and N005 in incubated soil were degraded approximately 23%, 22% and 15%, respectively. Also The scanning electron microscope examination of coating material revealed that particle surface became gradually shattered with the time after the soil treatment.

• Radiation Oncology Journal
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• v.27 no.1
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• pp.35-41
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• 2009

Purpose: This study was designed to determine the optimum radiotherapy technique for internal mammary node (IMN) irradiation after breast-conserving surgery. Materials and Methods: We selected ten cases of early stage partial mastectomy for plan comparison. Five of the patients were treated to the right-side breast and the rest of the patients were treated to the left-side breast. For each case, four different treatment plans were made to irradiate the entire breast, IMNs and supraclavicular lymph nodes (SCLs). The four planning techniques include a standard tangential field (STF), wide tangential field (WTF), partially wide tangential field (PWT) and a photon-electron mixed field (PEM). We prescribed a dose of 50.4 Gy to the SCL field at a 3 cm depth and isocenter of the breast field. Results: The dose distribution showed clear characteristics depending on the technique used. All of the techniques covered the breast tissue well. IMN coverage was also good, except for the STF, which was not intended to cover IMNs. For the cases of the left-side breasts, the volume of the heart that received more than 30 Gy was larger (in order) for the WTF, PWT, PEM and STF. For radiation pneumonitis normal tissue complication probability (NTCP), the PWT showed the best results followed by the STF. Conclusion: Despite the variety of patient body shapes, the PWT technique showed the best results for coverage of IMNs and for reducing the lung and heart dose.

• Journal of Gastric Cancer
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• v.13 no.3
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• pp.164-171
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• 2013

Purpose: Laparoscopy-assisted distal gastrectomy for early gastric cancer has gained acceptance and popularity worldwide. However, laparoscopy-assisted distal gastrectomy for advanced gastric cancer is still controversial. Therefore, we propose this prospective randomized controlled multi-center trial in order to evaluate the safety and feasibility of laparoscopy assisted D2-gastrectomy for advanced stage gastric cancer. Materials and Methods: Patients undergoing distal gastrectomy for advanced gastric cancer staged cT2/3/4 cN0/1/2/3a cM0 by endoscopy and computed tomography are eligible for enrollment after giving their informed consent. Patients will be randomized either to laparoscopyassisted distal gastrectomy or open distal gastrectomy. Sample size calculation revealed that 102 patients are to be included per treatment arm. The primary endpoint is the non-compliance rate of D2 dissection; relevant secondary endpoints are three-year disease free survival, surgical and postoperative complications, hospital stay and unanimity rate of D2 dissection evaluated by reviewing the intraoperative video documentation. Discussion: Oncologic safety is the major concern regarding laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Therefore, the non-compliance rate of clearing the N2 area was chosen as the most important parameter for the technical feasibility of the laparoscopic procedure. Furthermore, surgical quality will be carefully reviewed, that is, three independent experts will review the video records and score with a check list. For a long-term result, disease free survival is considered a secondary endpoint for this trial. This study will offer promising evidence of the feasibility and safety of Laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Trial Registration: NCT01088204 (international), NCCCTS-09-448 (Korea).

• Korean Journal of Ecology and Environment
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• v.46 no.2
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• pp.276-288
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• 2013

The present study investigates the effects of elevated soil nitrogen on growth and decomposition of Oryza sativa shoots. The plants were cultivated in greenhouse until leaf senescence and the total biomass of the plant increased 1.9 times at nitrogen addition plot. Total C and N content in shoot increased; however, lignin, C/N, and lignin/N levels decreased in the N-treated soil. The shoot litters collected from the control and N-treated soil were tested for decay and microbial biomass, $CO_2$ evolution, and enzyme activities during decomposition on the control and N-treated soil at $25^{\circ}C$ microcosm. The remaining mass of the shoot litter was approximately 6% higher in the litter collected from the control soil (53.0%) than the litter collected from high N-treated soil (47.1%). However, the high N-containing litter exhibited faster decay in the control soil than in the N-treated soil. The litter containing high N, low C/N, and low lignin/N showed a higher decomposition rate than that of low quality litter. The N-addition showed decreased microbial biomass C and dehydrogenase activity in soil; however, it exhibited high microbial biomass N and urease activity in soil. When the high N-containing litter decays on the N-treated soil, the microbial biomass C increased rapidly at the initial phase of decomposition and decreased thereafter, and dehydrogenase activity was less that of other treatment; however, there was no effect on the microbial biomass N. The urease in the decomposing litter was highest during the early decomposition stage and dramatically decreased thereafter. The present findings suggested that the N-addition increased N content in litter, but inhibited the decomposition process of above-ground biomass in terrestrial ecosystems.

• Childhood Kidney Diseases
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• v.1 no.1
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• pp.46-52
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• 1997

Urinary tract infection (UTI) in children has been known to be a cause of renal damage, leading to scar formation, hypertension and renal failure. And vesico-ureteral reflex (VUR), frequently accompanying UTI in young children, has been incriminated as the main factor causing scar formation. This retrospective study has been undertaken to see the relationship among UTI, VUR and renal scar formation. Study population consisted of 291 children (boy 134, girl 42) with UTI, who have been admitted to the Pediatric Department of Kyungpook University Hospital during 6 1/2 year period from January 1990 to June 1996. VUR was diagnosed by VCUG and renal scar by ultrasonogram, DMSA scan (or DMSA SPECT) and IVP. The following result were obtained. Sexual difference showed male predominance (male to female, 134:42) below 1 year of age, and female predominance (male to female, 11:35) over 5 years of age were rioted. VUR has been found in 64 children (22%) and the degree of reflux, classfied by the method proposed by 'International Reflux Study in Children', were as follows ; Grade I : 4.0%, Grade II : 3.0%, Grade III : 2.7%, Grade IV : 5.8% and Grade V : 6.2%. There was no sexual difference E.coli was the most predominant infecting agent occurring in 167 children (57%), and end-stage renal failure was diagnosed at the time of first admission in 5 children with Grade V VUR. Renal scar has been noted in 49 out of 582 kidneys (8.4%), and the incidence of scar foramation according to the degree of VUR were as follow ; Grade 0 (No reflux) : 1.2%, Grade I : 6.7%, Grade II 27.3%, Grade III 29.4%, Grade IV : 57.1%, and Grade V : 100%. In summary, present study shows that renal scar formation in UTI has close correlation with the severity of VUR occurring more frequently in severe reflux, so that early diagnosis and proper treatment of UTI and VUR is of paramount importance in preventing renal damage in children with UTI.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.91-97
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• 2007

To evaluate the physiological status of laying flocks, the blood chemistry values were measured and analyzed in various ages under different feeding conditions. Total 671 birds from 48 Hyline brown hens flocks from 13 different poultry farms were bled at the ages of day(s) 1, 11, 21, 50, 80, 120, 180, 240, 300, 400, and 500. The 17 blood chemistries including glucose, lipids, proteins, enzymes, electrolytes and metabolic by-products were measured with an autoanalyzer. Blood glucose showed the highest at the hatching day not relate with the dietary carbohydrates and energy, but tended to decrease during the rest of growth stage in hens. Total blood protein, albumin and globulin increased depending on the ages even though dietary protein was decreased. Blood lipid was greatly changed at different growth stages. Cholesterol was the highest at hatching period and maintained consistently until the 120 days of age. It was increased in birds after 180 days of age. HDL was also highest in hatchery, but decreased greatly after 180 days of age. However, TG was the lowest at one day old, but was increased up to 10 times after 180 days of age compared to that of one day old. The enzyme activities were different. AST, ALT, and GGT showed comparatively contained consistently, whereas amylase was slowly decreased. Blood P, Na, K and Cl showed consistency, but Ca content was increased upto two times of the one day of age. The results from this study showed that the blood chemistry values were affected by the general metabolic status of the host with ages not by feeding conditions. Further, the standard data of age-dependent blood chemistry values in the laying flocks were obtained, which can be utilized for early detection of the changes in the physiological status occurred by the infectious or metabolic diseases. The results of these analyses seemed to be useful to increase the productivity of laying flocks through rapid and proper veterinary medical treatments.

• Korean Journal of Poultry Science
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• v.41 no.4
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• pp.261-270
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• 2014

This study was conducted to establish the method for preserving chicken primordial germ cells (PGCs) that enables long-term storage in liquid nitrogen ($LN_2$) for developmental engineering or preservation of species. The purpose of this study is to clarify the effects of simple freeze-thaw treatment on viability of PGCs in chickens and to the optimal protocol for PGCs freezing. PGCs obtained from the germinal gonade of an early embryos of 5.5~6 day (stage 28) of Isa Brown, Korean Ogye (KO), White Leghorn and Commercial breeds, using the MACS method were suspended in a freezing medium containing a freezing and protecting agents (e.g. dimethyl sulfoxide (DMSO), ethylene glycol (EG) and propylene glycol (PG)). The gonadal cells, including PGCs, were then frozen in 1 of the following cryoprotectant treatments : 2.5%, 5%, 10%, 15%, and 0% cryoprotectant (DMSO, EG, PG) as a control. Effects of exposure to simple freezing, with different concentrations of the cryoprotectant solution, were examined. After simple freezing, the viability of PGCs after freeze-thawing was significantly higher for Commercial breeds ($88.7{\pm}2.4%$) than KO ($85.1{\pm}0.4%$), Isa Brown ($84.6{\pm}0.2%$) and White Leghorn ($85.9{\pm}0.1%$) (p<0.05) using 10% EG cryoprotectant. Therefore, these systems may contribute in the improvement of cryopreservation for a scarce species in birds preservation. This study established a method for preserving chicken PGCs that enables systematic storage and labeling of cryopreserved PGCs in liquid ($LN_2$) at a germplasm repository and ease of entry into a database.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.3
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• pp.257-266
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• 2010

This study was carried out to investigate the effect of feeding whole crop barley silage (WBS) on the growth performance, gain, feed requirement, carcass grade and beef quality of Hanwoo steers in 1999 to 2001. Twenty one steers were allocated, and divided into three treatment groups which fed rice straw only (control), WBS only, and fresh rice straw silage plus WBS during overall period ad libitum. Concentrates were fed at 1.5% level of live-body weight during growing stages, 4~12 months of age, at 1.8% level of live-body weight during early fattening stages, 13~18 months of age, and ad libitum after late fattening stages, 19~27months of age. The production yields of WBS were 17,135 kg as a silage, and 6,011 kg as a dry matter per ha, and the quality of WBS was 2~3 grade, while that of rice straw silage was 4grade. The daily gain with feeding of WBS (0.70 kg) during experimental period was higher than that of control group (0.65 kg), and the concentrate requirement (7.31 kg) per kg gain in WBS was lower than that of control (8.95 kg). The effects of gain and feed efficiency were very distinct during growing stage. i.e., the daily gain of WBS (0.84 kg) was increased by 65% compared to control (0.51 kg), and the concentrate requirement (4.16 kg) per kg gain in feeding of WBS was decreased by 35%, compared to control (6.39 kg). Meat quality with WBS was higher than that of control. Frequency rate of 1 and/or $1^+$ grade, and marbling score of feeding of WBS were 62.5% and 4.38, while those of control were 37.5% and 2.75, respectively. The results of the sensory evaluation showed that Hanwoo beef fed with WBS were better than that of control. In conclusion, feeding of WBS was desirable to improve daily gain, reduction of concentrates, feed efficiency and meat quality of Hanwoo steers.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.324-331
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• 2009

Peeled whole onions (PWO) were cleaned at various hypochlorous acid (HA) concentration and steeping time and packed in LDPE bag keeping at $10^{\circ}C$ for 12 days and $35^{\circ}C$ for 3 days, in order eventually to examine microbiology, surface color and sensory quality. At the early stage of storage, it was found that total bacterial counts at H-II keeping at $10^{\circ}C$ after 1 minute steeping were $2.60\;{\pm}\;0.18\;log\;CFU/g$, and those after 3 minutes steeping were $2.10\;{\pm}\;0.18\;log\;CFU/g$ which showed less than the control. The total bacterial counts at H-III were detected after 4 days. The total bacterial counts of PWO treated HA increased as steeping time became longer, HA concentration increased, and storage temperature went down. E. coli was not detected at all treatments. It was also found that during the treatment the L-value showed decreasing trend, but the parameter a- and b- value showed increasing trend. But these trends were mitigated as HA concentration increased. The result of sensory quality evaluation for the appearance showed that the sample stored with $10^{\circ}C$ gained higher evaluation than that with $10^{\circ}C$, while the control and H-III gained highest points significantly (p < 0.05) for the sample keeping at $10^{\circ}C$ after 12 days storage. The sensory odor of onion showed similar to that for the appearance, and the 8-day treatments of H-II and H-III showed no significantly difference (p < 0.05). On the basis of the results above, it is likely to be more effective to prolong the period of circulation of PWO if you use HA over 50 ppm for washing PWO and storage at $10^{\circ}C$. This study will contribute to improve safety and quality in circulation of PWO.