• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.19-25
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• 2017

This study was conducted to investigate the effects of nitrogen fertilization on physiological characteristics and growth of Populus sibirica seedlings in a semi-arid area, Mongolia. 2-year-old P. sibirica seedlings were planted in May, 2015 with applications of urea 5 g (N1), 15 g (N2), 30 g (N3) and ammonium sulfate 33 g (NS; same nitrogen amount with N2) to each seedling. Chlorophyll contents were significantly different among treatments in August, but not in June and July. The lower chlorophyll contents in August than those in June and July might be related to leaf senescence. In June and July, net photosynthetic rate was higher in NS and N2 than in the control. Unlike the tendency of photosynthesis, transpiration rate was highest in N2, but lower in NS than in any other nitrogen treatments. Relative growth rate of root collar diameter was significantly higher only in NS than in the control and it of height did not differ among treatments. Leaf area in nitrogen treatments was not significantly different from that in the control. Ammonium sulfate seemed to be more suitable fertilizer than urea for the early growth of P. sibirica seedlings in the study site. However, as the effects of urea and ammonium sulfate on soils and seedlings were different, further studies would be necessary to determine the optimal amount of ammonium sulfate.

• Korean Journal of Ichthyology
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• v.35 no.2
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• pp.91-100
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• 2023

The early life history of Silurus microdorsalis living in Jahocheon Stream was studied by observing egg and morphological development. Live fish were captured in June 2018, then reared in a circulating filtration system under a 14L : 10D photoperiod with a water temperature of 18℃. To artificially induce spawning, females were injected with 0.5 mL of Ovaprim (Syndel, Nanaimo, BC, Canada) per kg of body weight, and males were injected with 10,000 IU/kg body weight of human chorionic gonadotropin. Approximately 15 h later, eggs were artificially inseminated by the dry method. Mature eggs were light pale yellow, which separated them from immature eggs. Fertilized eggs were 2.16±0.06 mm (n=8) in diameter and fully hatched at 181 h after fertilization. The fertilization rate was 63.1±2.2%, and 10.0±3.7% of the embryos were malformed at 18℃. The rates of development were 181 h at 18℃, 109 h at 21℃, and 76 h at 24℃. The larval size immediately after hatching was 4.64±0.22 mm (n=8), and the larvae displayed negative phototaxis at 1 day after hatching. The total larval length on 7 days after hatching was 12.47±0.53 mm, with 25~30 basal anal fin rays and 14~16 basal caudal fin rays observed. The total larval length was 14.13±0.51 mm on 9 days after hatching, and approximately 90% of the black endoplasmic reticulum was deposited on the head and body. The dorsal fin had formed, and a single basal body was observed. On 15 days after hatching, the total larval length was 16.69±0.31 mm; the number of basal caudal fin rays (18 poles) was an integer because 2 dorsal fin basal rays and 60~63 anal fin basal rays were observed. The total larval length was 28.96±1.10 mm on 50 days after hatching; the numbers of caudal fins (n=18), dorsal fins (n=3), pectoral fins (n=11), and anal fin basal rays (n=67~73) were integers.

• Korean Journal of Food Science and Technology
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• v.4 no.4
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• pp.239-244
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• 1972

Commercial edible soybean oil was introduced into plastic containers. Colorless transparent (control), red transparent, green transparent cellophane films and, also, colorless transparent cellophane films coated respectively with Cemedine C, Cemedine C containing 10% pyridine, benzophenone, and p-aminobenzoic acid were prepared, and the % transmittance of each film to lights at U.V. and visible regions were measured. The containers were covered with the films and irradiated simultaneously with direct sunlight for 4.5 hours daily. The peroxide values of the oils in the plastic containers were determined at regular intervals. The effects of the Alms on the PV development of the oils were compared with that of the control, i.e., the colorless transparent films.The red and green films showed strong retarding effects ell the PV development. The red films showed a slightly stronger effect than the green ones. The colorless transparent films coated with Cemedine C showed an appreciable retarding effect. The films had absorbed the lights at the U.V. and visible regions considerably. The pyridine and benzophenone coated films lost their retarding effects after 10 and 4 days respectively. The p- aminobenzoic acid coated films showed a considerable retarding effect throughout the experimental period. The films had absorbed the lights strongly .As a whole, the retarding effects of the films on the PV development were, in decreasing order. as follows; Red> Green> p-Aminobenzoic acid coated > Cemedine Ccoated) Control > Pyridine coated > Benz ophenone coated

• Horticultural Science & Technology
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• v.28 no.4
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• pp.567-573
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• 2010

Research was initiated to investigate early establishment characteristics and germination pattern of fine-textured fescues (FF). Six varieties from Chewings fescue ($Festuca$ $rubra$ L. ssp. $commutata$ Gaud., CF), creeping red fescue ($F.$ $rubra$ L. ssp. $rubra$ Gaud., CRF), hard fescue ($F.$ $ovina$ ssp. $longifolia$ Thuill., HF) and sheep fescue ($F.$ $ovina$ L., SF) were evaluated in the study. An alternative environmental condition requiring a FF germination test by International Seed Testing Association (ISTA) was applied in the experiment, consisting of 8-hr light at $25^{\circ}C$ and 16-hr dark at $15^{\circ}C$ (ISTA conditions). Daily and cumulative germination patterns were measured and analyzed on a daily basis. Significant differences were observed in germination pattern, days to the first germination, days to 50% germination, days to 60% germination, and germination rate. The final germination percentage was variable with species and varieties, being 40.25 to 82.00% at the end of study. There were considerable variations in early germination characteristics and germination pattern among FF species. The first germination in all entries except HF was initiated between 5 and 6 DAS (days after seeding) under ISTA conditions, while HF between 6 and 7 DAS, being 1 day later. It was 8 to 10 DAS in days to the 50% germination, which was 2 to 4 days after the first germination date. Days to the 60% germination were 9.10 to 14.80 DAS under ISTA conditions, being 5.70 days in differences among the entries. CF 'Jamestown II' and 'Shadow II' and HF 'Aurora Gold' were the fast varieties. The slowest one was HF 'Rescue 911'. Among FF species, turf establishment speed was becoming faster in CRF, SF, HF and CF in this order. Information on differences in germination characteristics and pattern from this study would be usefully applied for golf course design and construction, when established with FF.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.331-338
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• 1994

The experiment was conducted to determine if seed size and seed coat color of soybean might be effective in water uptake and cotyledon damage after imbibition, and hypocotyl elongation. Eight soybean cultivars were separated into two classes of large and small seed based on seed weight, and each class included two cultivars with yellow and black seed color, respectively. Small seed size group was superior in water uptake by seed for 24 hour in imbibition at $25^{\circ}C$ , but its differences decreased as soaking time increased. Small seed cultivars germinated faster and had better germination rate than large ones. However, cultivars with black seed coat showed more slow water uptake at initial time and faster germination than yellow seed, but in 24 hour after imbibition, cultivars with black seed coat had higher water uptake rate than yellow seeds. Small seed cultivar group showed no cotyledon damage in imbibition for 24 hour while large seed cultivars were damaged 78% of cotyledon, and black seed showed low cotyledon damage compared to yellow seed. Hypocotyl length was shorter in large seed rather than in small seed, but hypocotyl thickness in large seed was more thick than in small seed. In correlation coefficients, seed coat rate, embryo rate exhibited significantly negative association with seed weight, and the correlation of seed weight with water uptake in 3 hour after soaking was significantly negative, but in 24 hour showed positive correlation.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.12
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• pp.889-896
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• 2013

Advanced Oxidation Processes (AOP) have been interested for removing micropollutants in water. Most of water treatment plants (WTPs) located along the lower part of Nakdong River have adopted the $O_3/BAC$ process and have interesting in peroxone process a kind of AOP. This study evaluated the removal characteristics of residual hydrogen peroxide ($H_2O_2$) combining with the biofiltration process in the next BAC process when the hydrogen peroxide is applied for the WTP operating $O_3/BAC$ process. In the experiment, changing the temperature and the concentration of $H_2O_2$ of influent, the biofiltration process showed rapidly dropped the biodegradability when the $H_2O_2$ concentration was increased and lowered water temperature while BAC process maintained relatively stable efficiency. The influent fixed at $20^{\circ}C$ and the concentration of $H_2O_2$ at 300 mg/L was continuously input for 78 hours. Most of the $H_2O_2$ in the influent did not remove at the biofiltration process controlled 5 to 15 minutes EBCT condition after 24~71 hours operating time while BAC process controlled 5 to 15 minutes EBCT showed 38~91% removal efficiency condition after 78 hours operating time. Besides, after 78 hours continuously input experiment, the biomass and activity of attached bacterial on the biofilter and BAC were $6.0{\times}10^4CFU/g$, $0.54mg{\cdot}C/m^3{\cdot}hr$ and $0.4{\times}10^8CFU/g$, $1.42mg{\cdot}C/m^3{\cdot}hr$ respectively. These biomass and activity values were decreased 99% and 72% in biofilter and 68% and 53% in BAC compared with initial condition. The biodegradation rate constant ($k_{bio}$) and half-life ($t_{1/2}$) in BAC were decreased from $1.173min^{-1}$ to $0.183min^{-1}$ and 0.591 min to 3.787 min respectively according to increasing the $H_2O_2$ concentration from 10 mg/L to 300 mg/L at $5^{\circ}C$ water temperature and the $k_{bio}$ and $t_{1/2}$ were $1.510min^{-1}$ to $0.498min^{-1}$ and 0.459 min to 1.392 min at $25^{\circ}C$ water temperature. By increasing the water temperature from $5^{\circ}C$ to $15^{\circ}C$ or $25^{\circ}C$, the $k_{bio}$ were increased 1.1~2.1 times and 1.3~4.4 times. If a water treatment plant operating $O_3/BAC$ process is considering the hydrogen peroxide for the peroxone process, post BAC could effectively decrease the residual $H_2O_2$, moreover, in case of spilling the $H_2O_2$ into the water process line, these spilled $H_2O_2$ concentration can be able to decrease by increasing the EBCT at the BAC process.

• Pediatric Infection and Vaccine
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• v.23 no.2
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• pp.128-136
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• 2016

Purpose: This study was done to define clinical characteristics of fever without localizing signs (FWLS) in infants younger than 100 days of age with a goal of providing baseline data to establish a new diagnostic paradigm in the future. Methods: We reviewed medical records of 183 patients who admitted to Daegu Catholic University Medical Center for FWLS younger than 100 days of age from January 2013 to September 2015 retrospectively. Demographic, clinical features and laboratory findings were analyzed. Patients were divided into serious bacterial infection (SBI) and non-SBI groups, and then were compared between two groups to find risk factors for SBI. Results: Among 183 patients, lumbar puncture was performed in 98.9% and CSF pleocytosis was present in 35.9%. Sterile CSF pleocytosis was found in 43% of urinary tract infection (UTI) patients. None had concomitant bacterial meningitis in patients with UTI. As final diagnosis, febrile syndrome without source (25.7%) was most common. Among SBI, UTI was most common (99%). Birth weight, ESR, and CRP were significantly higher in SBI group compared to non-SBI group. Male sex (OR 4.93, 95% CI 1.60-15.24) and pyuria (OR 18.88, 95% CI 6.76-52.76) were identified as risk factors for SBI. Presence of sibling (OR 0.30, 95% CI 0.11-0.83) was significantly lower in SBI group. Conclusions: Our results showed UTI was the most common SBI in young infants with FWLS. Though aseptic meningitis can be coexisting with UTI, lumbar puncture may not be necessary in all patients having UTI.

• Korean Journal of Weed Science
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• v.11 no.2
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• pp.111-116
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• 1991

This studies were conducted to get the basic information on the growth habits of Scirpus planiculmis F. Schmidt for control in poldered paddy field. The distribution of corm was about 16% in 0-5cm, 66% in 5-8 cm. 18% in 8-10cm depth of underground. The mean depth of total corm distribution was about 6.51cm. Number of rhizomes and dormant buds per corm were one to four, respectively. Number of rhizomes. dormant buds and total buds(rhizome+dormant bud) were 2.34, 2.85 and 5.20, respectively. The phyllotaxy of S. planiculmis was 1/3 and bracteal leaf were showed from first to 4th leaves. The period of propagation to 100 plants from emergence was 58.52 and 48 days for corm seeded on March 25th, b4ay 7th and June 6th respectively. Days to emergence of S. planiculmis from emergence of previous plant was gradually shorted. as order of propagation from corm seeded progressed. The other side, length of rhizome, plant height and diameter of culm was increased. The plant height of S. planiculmis was higher than rice plant from early stage in rice direct seeding culture, and from 30 dats after transplanting in rice transplanting culture. Speed of propagation was faster in rice direct seeding culture than in rice trasplanting culture.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.198-212
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• 2002

A numerical variation and abnormalities were studied on egg bags and embryos of Korean salamander, Hynobius leechii from agricultural habitat. The teratogenic and toxic effects of fungicide benomyl were also investigated with early embryos from non-agricultural habitat. We collected 144 egg bags from agricultural region, and 3418 of early embryos were contained. The lengths of egg bags were varied from 10 to 23 cm and the most frequent length was 19 cm. The number of embryos was varied from 7 to 43, and the most frequent range was 22 to 26. Spontaneous abnormalities were occurred in 406 embryos among 116 egg bags, and 24 kinds of external abnormalities were found. Individuals showing severe external defect were histologically studied and they showed optic dyspalsia, thyroid carcinoma, somatic muscular dysplasia, partial biaxial structure, decrease of red blood cells in the heart, cephalic degeneration and intestinal dysplasia. 385 embryos from non-agricultural region were exposed to 200 nM${\sim}$ 1 ${\mu}$M of benomyl at blastula or gastrula for 12 days. All embryo were dead in the concentration of 1 ${\mu}$M (LD$_{100}$) and 75% of embryos were dead in 800nM of benomyl. Speciflc effect due to benomyl was acrania or cephalic dysplasia and this restult suggests that the benomyl inhibit stongly to the development of neural tissue. These abnormal developments may be caused by antimitotic action, inhibition of tubulin complex, destruction of microtubule, inhibitions of neurulation and closing of neural fold, and by the inhibition of the movement of neural crest cells.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.4
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• pp.177-188
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• 1989

The purpose of this study was to investigate the detoxifying effect on PSP-infested sea mussel, Mytilus edulis, by heating treatment and correlation between the PSP toxicity and the environmental conditions of shellfish culture area such as temperature, pH, salinity, density of Protogonyaulax sp. and concentration of inorganic nutrients such as $NH_4-N,\;NO_3-N,\;NO_2-N\;and\;PO_4-P$. This experiment was carried out at $Suj\u{o}ng$ in Masan, Yangdo in Jindong, $Hach\u{o}ng\;in\;K\u{o}jedo\;and\;Gamch\u{o}n$ bay in Pusan from February to June in $1987\~1989$. It was observed that the detection ratio and toxicity of PSP in sea mussel were different by the year even same collected area. The PSP was often detected when the temperature of sea water about $8.0\~14.0^{\circ}C$. Sometimes the PSP fox of sea mussel was closely related to density of Protogonyaulax sp. at $Gamch\u{o}n$ bay in Pusan from March to April in 1989, but no relationship was observed except above duration during the study period. The concentration of inorganic nutrients effects on the growth of Protogonyaulax sp., then effects of $NO_3-N$ was the strongest among them. When the PSP-infested sea mussel homogenate was heated at various temperature, the PSP toxicity was not changed significantly at below $70^{\circ}C$ for 60 min. but it was proper-tionaly decreased as the heating temperature was increased. For example, when the sea mussel homogenate was heated at $100^{\circ}C,\;121^{\circ}C$ for 10 min., the toxicity was decreased about $67\%\;and\;90\%$, respectively. On the other hand, when shellstock sea mussel contained PSP of $150{\mu}g/100g$ was boiled at $100^{\circ}C$ for 30 min. with tap water, the toxicity was not detected by mouse assay, but that of PSP of $5400{\mu}g/100g$ was reduced to $57{\mu}g/100g$ even after boiling for 120 min.