• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.4
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• pp.318-321
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• 2006

This study was conducted in 2002 and 2003 to investigate variation on rice quality associated with cooking, and eating qualities under the three different fertilizer levels, none fertilizer level($N-P_2O_{5-}K_2O=0-0-0kg/ha$), ordinary fertilizer level($N-P_2O_{5-}K_2O=1l0-45-57kg/ha$), and heavy fertilizer level($N-P_2O_{5-}K_2O=180-90-110kg/ha$). The eight resistant near-isogenic lines(NILs) for bacterial blight in rice were examined for grain appearances, several physicochemical properties, and palatability value measured by Toyo taste meter. Significant variations in NILs(V), Years(Y), and VxY interaction were recognized in grain length and palatability value under the none fertilizer cultivation, in grain width under the heavy fertilizer cultivation, and in white belly ratio under the three different fertilizer cultivations, respectively. According to increase the fertilizer application rate, variation in grain length and grain width were not significant, but grain thickness was thinner under the ordinary and heavy fertilizer cultivations than under the none fertilizer cultivation. On the other hand, white belly ratio, protein content and Mg/K ratio increased, while amylose content and palatability value lowered. Alkali spreading value lowed under the heavy fertilizer cultivation than under the none and ordinary fertilizer cultivations. Palatability value was significantly low in the line carrying XalJ than in the other lines under the ordinary fertilizer cultivations.

• Clinical and Experimental Reproductive Medicine
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• v.38 no.2
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• pp.87-92
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• 2011

Objective: This study aimed to determine the safety and clinical effect of artificial shrinkage (AS) in terms of assisted hatching of fresh blastocysts. Also, we evaluated the correlation between patient age and the effect of AS on clinical outcome. Methods: Two AS methods, using a 29-gauge needle and laser pulse, were compared. Seventy-three blastocysts were shrunk using a 29-gauge needle and the same number of other blastocysts were shrunk by a laser pulse. We evaluated the shrunken blastocysts hourly and considered them viable if they re-expanded >70%. Blastocyst transfer cycles (n=134) were divided into two groups: a control group consisted of the cycles whose intact embryos were transferred (n=100), while the AS group consisted of the cycles whose embryos were replaced following AS (n=34). The implantation and pregnancy rates of the control group and AS group were compared ($p$ <0.05). Results: The re-expansion rates of the 29-gauge needle and laser pulse AS groups were similar (56 [76.7%] vs. 62 [84.9%], respectively). All of the remaining shrunken blastocysts were re-expanded within 2 hours. There was no degeneration of shrunken blastocysts. The total and clinical pregnancy rate of the AS group (23 [67.6%]; 20 [58.8%], respectively) was significantly higher than that of the control group (47 [47.0%]; 39 [39.0%], respectively). In the older patient group, there was no difference in the clinical outcomes between the AS and control groups. Conclusion: These results suggest that AS of blastocoele cavity, followed by the transfer, would be a useful approach to improve the clinical outcome in cycles in which fresh blastocyst stage embryos are transferred.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.10-17
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• 2008

The objective of this study was to estimate the pollutant loads from paddy fields by cultivation practices using a non-point-sources models. One of them is CREAMS-PADDY model that was developed considering the water balance and mass balance of paddy fields. The CREAMS-PADDY model was applied to provide basic data to reduce runoff loadings under various scenarios such as various water management control and various fertilizer condition. The model was verified against T-N, T-P and runoff flow data collected during cropping periods at 2000. The model results agreed well with the measured data in verification. The results showed that the model could be used for estimating the runoff loadings from irrigated paddy fields by cultivation practices was possible. Comparison of simulated the standard height and the sluice management of T-N and T-P runoff loadings from paddy fields were +32.4%, +10.3% in 10 mm below the standard height, -29.2%, -35.9% in 20 mm above the standard height, 52.6%, 59.0% in 40 mm above the standard height, respectively. Comparison of simulated the standard fertilizer and the fertilizer control of T-N and T-P runoff loadings from paddy fields were -1.3%, -21.7%in reduction of conventional fertilizer 30%, -1.0%, -12.5% in reduction of standard fertilizer 30%, respectively. Therefore, reducing nonpoint-sources nutrient loading by reducing fertilization may not work well in the range of normal paddy rice farming practices, and instead it could be achieved by reducing surface drainage outflow.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.35-42
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• 2019

Organic fertilization (OF) was an effective management strategy to improve crop yield and soil fertility. Determination of optimum application rate has been received great interest as a major research field. In this study, we evaluated optimum application level of three different organic fertilizers; mixed expeller compost (MEC), mixed organic fertilizer (MOF) and organic complex fertilizer (OCF), for garlic cultivation. Treatments consisted of MEC, MOF, OCF (50, 100, 150% of standard nitrogen input), inorganic fertilizer(NPK, N-P₂O₅-K₂O : 250-78-128 kg ha^-1) and no-fertilization (control). Overall, the yields of garlic under MEC, MOF and OCF 100% (5,337, 5,617 and 5,276 kg ha^-1) were higher than under control (4,496 kg ha^-1). The 100% of three OFs treatements showed the highest yield and bulb diameter, similar with NPK, while leaf length and bulb height were not significantly different among all treatments. The 150% of three OFs rather decreased yield. The highest nitrogen use efficiency (38.4 and 38.0%) was observed in MOF 100% and OCF100%, which was the most similar with that in NPK (38.8%). As OF application rate increased, pH was decreased, but soil NO₃-N and NH₄-N were increased. There was no significant difference in soil organic matter (OM), av. P₂O₅ and Ex. cation values. From these results, 100% application of OFs could be recommended as a suitable input level for garlic cultivation, regardless of organic fertilizer types. Further study might be required to evaluate long-term OF application effect on soil health and crop productivity.

• Journal of Embryo Transfer
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• v.19 no.3
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• pp.239-244
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• 2004

The present study was to investigate the pregnancy rate, gestation length and abortion rate of the recipients which transferred blastocysts produced by in-vivo collection, in-vitro fertilization (IVF) and nuclear transfer (NT). In addition, we investigate the birth weight and survival rate of the calves derived from the same methods. The pregnancy rate was 56.3％ in-vivo blastocysts, significantly higher than 19.4％ in NT blastocysts (p<0.05) but not significantly different from 30.0％ in IVF blastocysts. The abortion rate and the gestation length did not differ among the treatment groups (abortion rate: 0, 22.2 and 16.7％ respectively; gestation length: 278.8, 289.4 and 281.4 days respectively). The mean birth weight was significantly higher in NT calves (39.9kg) than in-vivo calves (25.5kg p<0.05). Recipients of in-vivo blastocysts (n=9) had all normal delivery and all of their calves survived on the 60$^{th}$ day from the birth. Recipients of IVF blastocysts (n=7) had all normal delivery but one of their calves died on the 48$^{th}$ day from the birth. Among recipients of NT blastocysts (n=5), three had normal delivery and two had Caesarean section. Among calves born through normal delivery (n=3) two died just after delivery but those born through Caesarean section all survived on the 60th day from the birth.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.4
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• pp.247-253
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• 2008

Winter annual green manure crops may be an effective tool for environmental-friendly agriculture system. The effect of legume (hairy vetch), non-legume (rye) and N fertilization ($190kg\;N\;ha^{-1}$) was examined and compared on red-pepper yield, nitrogen uptake, carbohydrate composition, and soil N and C contents. We monitored soil N and C for 120 days after incorporation (DAI) of green manures or mineral fertilizer. The mineralization of nitrogen reached the maximum around 30 DAI. The amount of inorganic nitrogen supplied by mineralization of hairy vetch residue was greater with than chemical N or rye. Photosynthetic rate was similar by 70 DAT in all treatments however, it in rye-incorporated red-pepper presented a sharp decline at later growth period. Leaf total nitrogen was greater with hairy vetch and chemical N than rye throughout the experiment. The soluble sugar increased steadily in all treatments from 40 to 110 days after transplanting (DAT) whereas starch showed a tendency of great decrease. Hairy vetch greatly promoted red-pepper growth by the later period however, chemical N showed the highest fruit yields.

• Journal of Korea Foresty Energy
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• v.23 no.2
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• pp.9-20
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• 2004

Growth and nutrients of Xinjiang poplar (Populus alba var. pyramidalis) seedlings treated with fertilizers and soil amendments were examined in nursery and windbreak at Dengkou after 6 months of treatments in Inner Mongolia, China. Soil water content was $10\%$ higher than that at most soils in desert. Height and diameter growth and foliar nitrogen (N) concentration were higher at N and nitrogen plus phosphorus (N+P) fertilizer treatments than other treatments. However, there were no differences in foliar P concentration among treatments in windbreak and foliar P concentration was higher at control than at other treatments in nursery. Yuho treatment increased height and diameter growth. Nitrogen appeared an influenciug factor for early growth of Xinjiang poplar, and P had a minor affect on growth. More long-time studies were needed to elucidate the effects of fertilizers and soil amendments on growth and nutrients of Xinjiang poplar.

• Korean Journal of Ichthyology
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• v.30 no.2
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• pp.75-83
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• 2018

This study is to observe species identification and early life history of Korean endemic species of Tanakia latimarginata and to use it as a basis for taxonomic studies. As a result of morphological identification, a dark band appeared at the margin of the anal fin, and the ovipositor color of the female was light orange. The shape of the egg was fusiform and sticky. The egg size (long${\times}$short diameter) averaged $4.41{\times}1.44mm$. The incubation time was 126 hours after the fertilization at an average water temperature of $21.0^{\circ}C$. Immediately after hatching, the larvae had egg yolk at an average total length of $5.91{\pm}0.18mm$ (n=5). At 18 days after hatching, the trunk fur was developed in the caudal fin with an average total length of $8.02{\pm}0.08mm$ (n=5). At 41 days after hatching, the larvae absorbed egg yolk at an average total length of $8.70{\pm}0.23mm$ (n=5). At 80 days after hatching, the average length of the fins was $12.6{\pm}0.28mm$ (n=5). The number of fin of the dorsal fin was iii.8, the anal fin iii.9~10, the caudal fin 19, lateral line scales 32~35 were similar to their brood stork.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.5
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• pp.272-279
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• 2002

A field experiment was conducted to investigate the effect of N-use efficiency and rice yield by rapeseed cake(organic fertilizer) application at panicle initiation stage in machine transplating cultivation from 1999 to 2000. The rice yield increased by 4% in "50% rapeseed cake application", by 2% in "30% rapeseed cake application" at panicle initiation stage, respectively. Amount of fertilizer N uptake was high according to increasing amount of rapeseed cake application at panicle initiation stage compared with conventional treatment, but percentage recovery of fertilizer N was higher in 30% rapeseed cake application than in 50% rapeseed cake application at panicle initiation stage. Thus, this result was thought that there was more adventageous in 30% rapeseed cake application than 50% rapeseed cake application at panicle initiation stage in the fertilizer reduction or N-use efficiency respects in rice paddy.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.6
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• pp.744-750
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• 2015

The objectives of this study were to investigate soil chemical characteristics for forest rehabilitation and suggest management in abandoned coal mine areas in Boryeong City, Chungcheongnam-do. Total study sites were seven sites, and soil properties analyzed were soil pH, total organic carbon (TOC), total-N, C/N ratio, and available $P_2O_5$ (A.v. P). Average soil pH (range) was 5.9 (4.5~7.0). Three study sites (Samgwang, Shinsung1, and Shimwon1) showed lower soil pH than standard (pH 5.6~7.3) of Korea Industrial Standards (KS) for abandoned coal mine forest rehabilitation. Average contents of TOC, and total-N were 1.5% (0.1~4.7%), and 0.10% (0.03~0.23%), respectively. Five study sites where the collapsed time was less than 10 years (Wangjashingang, Wonpoong, Samgwang, Shinsung1, and Shinsung2) showed lower TOC level than standard of KS (more than 1.2%). Wangjashingang, Wonpoong, Samgwang, and Shinsung1 showed lower level of total-N than standard of KS (more than 0.09%). C/N ratio of six study sites except Shimwon1 was out of proper range (15:1~30:1). Average A.v. P (range) was $20.7mgkg^{-1}$ (4.8~63.1), less than other abandoned coal mine fores rehabilitation areas in Mungyong City, and Hwasun-gun. TOC, total N and A.v. P increased with elapsed time from forest rehabilitation, while other soil properties did not show distinct pattern. Betula platyphylla was planted in Samkwang and Sinsung where soil pH was less than KS standard. Because the growth of Betula platyphylla can be limited in acid soil, it is necessary to neutralize soil pH to proper level with some soil amendment such as lime or shell of oyster. Furthermore, TOC, total-N and A.v. P in early stage of forest rehabilitation showed lower level than proper to vegetation growth. Therefore it needs continuous monitoring of soil characteristics and fertilization for vegetation growth and influx from surrounding forest in early stage of rehabilitation.