• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.295-301
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• 1996

This study was carried out to clarify the effect of sprout length, burried depth of seed and CaO$_2$ seed coating on emergence, seedling stand and early growth of rice in puddled-soil drill seeding at Junbuk in 1995. The cultivar tested was Dongjinbyeo(Japonica type). Although the longer sprouted seeds were caused the better seedling stand, 4mm sprout length of seeds appeared to be appropriate for good seedling stand and seeding uniformity, while 6mm sprouted seed resulted in ununiform seedling establishment. Rapid emergence and increased seedling stand were obtained by CaO$_2$ seed coating, which had effect more on soaked seed than on sprouted seed, but the seedling stand of sprouted seeds significantly reduced at deeper than 1cm seeding depth and also emergence rate of sprouted seeds significantly reduced at deeper than 2cm seeding depth.

• The Journal of the Korean life insurance medical association
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• v.28 no.1_2
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• pp.15-18
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• 2009

Background: Recent emergence of drug-resistant tuberculosis such as multidrug-resistant tuberculosis(MDR-TB) or extensively drug-resistant tuberculosis(XDR-TB) has become important health care problems. It has also became grave issues for insurance industries in determining medical risks. We have therefore strived to analyze the comparative mortality rates for drug-resistant tuberculosis through utilization of results from previous articles. Methods: Comparative mortality was calculated from source articles using mortality analysis methods. Results: Mortality ratio of MDR-TB was estimate to 1200%, and excess death rate was 110 per 1,000. Comparative mortality between MDR-TB and XDR-TB by Korean $study^{(1)}$ were 1750, 382, 405, 443, 1025, and 357%, for each 10 months study intervals, respectively. Total mortality ratio was 594% and total excess death rate was 60 per 1,000person. It was determined that the risk of XDR-TB was much greater than MDR-TB. Discussion; Pending the development of a novel anti-tuberculosis drug, it would be prudent to steer clear insuring XDR-TB during underwriting phase due to high medical cost that it creates.

• Environmental Analysis Health and Toxicology
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• v.23 no.4
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• pp.277-284
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• 2008

The ecotoxicological effects of 4-tert-octylphenol were observed on non-biting midge, Chironomus plumosus collected from Anyang stream in Seoul. The survival rate and adult emergence rate on C. plumosus exposed to octylphenol were not significantly affected. However, 4-tert-octylphenol induced developmental delay and disrupted sex ratio in high concentration of octylphenol. The mouth deformity such as tooth deletion or fusion in mentum, and tooth deletion in mandible were observed exposure to 4-tert-octylphenol. The deformity type of the mentum showed deletion (LT, 6.7%), and fusion (LT, 6.3%). Moreover, tooth deletion of mandible was observed in 4-tert-octylphenol treated groups (6.7%, 3 ppm).

• Asia pacific journal of information systems
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• v.32 no.1
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• pp.51-69
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• 2022

This study examines how consumers' intention to use a curbside pickup responds to the COVID-19 vaccination rates. With our first survey conducted in March 2021, we find that a low (high) vaccination rate is associated with consumers' high (low) intention to maintain contact avoidance and their high (low) anticipation for shipping delays. Heightened contact avoidance and anticipation for shipping delays may encourage consumers to use a curbside pickup. Our results also show that when a product is needed immediately, and a consumer expects shipping delays, s/he is more likely to use a curbside pickup. However, with our second survey conducted in November 2021, we find heterogeneous consumer responses to the vaccination rates. Specifically, consumers' political affiliation moderates the relationship between the vaccination rates and their intention to maintain contact avoidance. The association between the vaccination rates and the anticipation for shipping delays is also weakened compared to March 2021. Our empirical results illustrate how consumers' intention to use a curbside pickup emerges and changes amid the COVID-19 pandemic.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.169-172
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• 2003

Intact seeds of burcucumber (Sicyos angulatus L.) are not nearly germinated so that the farmers remove their arils before sowing. The study was carried out to measure the effort of aging, chilling, washing, chemical treatment, drying, and their sequential treatments on the germination of ones with arils and the seedling emergence. The seeds extruding over 1mm of their radicles and the seedlings with fully expanded cotyledons were counted daily for calculating the germination and the seedling emergence rates. Seedcoat softening using 10% NaOH solution somewhat enhanced their germination rate of the intact seeds harvested in the current year, but aging treatment done on 6 days at $45^{\circ}C$ after NaOH treatment increased the germination rate more than only NaOH treatment. A day washing after the NaOH treatment and a day chilling after the washing increasingly elevated the rates as well. Irrigation of 0.2% $\textrm{KNO}_3$ solution, moreover, showed the greatest germination rate of the priming treatments done during all the 7 day chilling. Drying the seeds after the combined treatment of chilling and priming more inclined the germination rate than nondrying ones, but red light treated during 24 hour desiccation was more effective in the germination rate increment than dark condition. The seeds done the sequential treatments of aging, NaOH, washing, combining chilling and priming and drying under red light illumination were germinated up to 80% but seedlings were emerged to 60%, lower than ones removed their arils.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.82-87
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• 2016

Herbicide options for weed control in sorghum is very limited, hence there is a need for exploring potential herbicides. Sorghum herbicide tolerance field trails were conducted at two locations, Yaechoun, Gyeongsangbuk-do, and Miryang, Gyeongsangnam-do, in 2013. Tolerance of sorghum was evaluated following the pre-emergence application of methabenzthiazuron 70% (WP), simazine 50% (WP), oxadiargyl 1.7% (EC), and dimethenamid-P 5% + pendimethalin 20% (EC) at the standard rate 157.5 g, 75 g, 5.1 g, and 75 g a.i. $10a^{-1}$, respectively. As well as double the standard rate. On a phytotoxicity scale of 0 to 9, methabenzthiazuron (WP) induced injury to sorghum up to level 1 at the standard rate and to 3 at double the rate, but did not significantly affect the yield any statistical difference from the untreated. Simazine (WP) induced phytotoxicity up to levels 2 and 4 at single and double rates, respectively. Simazine (WP) did not significantly affect yield: however, the values were numerically lower than those in the methabenzthiazuron (WP) treatment. Oxidiargyl (EC) and dimethenamid + pendimethalin (EC) induced no or slight phytotoxicity; however they failed to provide effective weed control at the standard rate (32 and 68% control, respectively). Out of the tested, methabenzthiazuron (WP) was found to have potential for use in sorghum whereas the other herbicides caused unacceptable levels of injury.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.203-209
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• 2001

Development and reproduction of the sweetpotato whitefly, Bemisia tabaci(B biotype) were investigated under different temperatures and host plants. Developmental periods from egg to pre-adult of whiteflies measured under four constant temperatures: they were 86.2 days at $15^{\circ}C$ and 17.0 days at $30^{\circ}C$. Lower threshold temperature and total effective temperature for the development of egg and nymph, and for the complete development (egg to emergence) were $10.1,\;11.6,\;11.1^{\circ}C$ and 110.3, 204.7, 317.3 degree days, respectively. The hatching and emergence rates were 87.0% at $25^{\circ}C$ and 76.7% at $20^{\circ}C$, which were higher than the results of other temperatures. The adult longevity was 23.6 and 14.0 days at $20^{\circ}C$ and $30^{\circ}C$, respectively. The highest average fecundity per female was 103.3 at $25^{\circ}C$. But there were no significant differences among the temperatures. The highest intrinsic rate of natural increase($r_{m}$) was 0.196 at $30^{\circ}C$ and the highest net reproduction rate ($R_{o}$) was 97.33 at $25^{\circ}C$. Developmental periods from egg to pre-adult of whiteflies were 21.2 on the tomato, 28.1 on red pepper, 22.2 on eggplant and 25.5 days on poinsetia. The hatching was highest (90.3%) on red paper and emergence rate was highest (89.6%) on eggplant. The longest longevity of adult female was 26.5 days on eggplant, and the average fecundity per female was greater on tomato and eggplant than on other host plants. The intrinsic rate of natural increase($r_{m}$) was the highest on tomato as 0.165 and the net reproduction rate ($R_{o}$) was the highest on eggplant as 106.1. As a result, the optimum range of temperature for the growth of B. tabaci was between $25^{\circ}C$ and $30^{\circ}C$, and the optimum host plant were tomato and eggplant among the plants tested.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.373-377
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• 1997

The bird repellent, methiocarb 50% WP, has been used to reduce the bird damage in the crop field in the European countries. The bird damage occaisonally would occur in the wet direct seeded rice and in soybean field, and resulted in decreasing the crop productivity by the reduction of seedling emergence rate. In this experiment, rice seeds, Hwasungbyeo(Oryza sativa), were coated with the different application rate of methiocarb, 5, 10 and 15 per kg seed, and soybean, Taegwangkong(Glycine max), 2.5, 5.0 and 7.5g. In rice, the seeds coated with 10 and 15g of methiocarb were not lost by bird, while those with 5g and control were lost to 37 and 50% of total seeds, respectively. No damage by birds was observed in rice seedling when the coleoptile and radicle of rice were emerged at 7 days after the water seeding. The crop injury of methiocarb reducing the emergence rate of seedlings, shortening the shoot length, and decreasing the leaf number was occurred at the treated of methiocarb 15g per kg seed. In soybean, the loss of the sprouting by birds was lower in the treatment of methiocarb 7.5g per kg seed than that in both the control and the treatments of methiocarb, 2.5 and 5.0g per kg seed. No crop injury by the treatment of methiocarb was observed in all application rate.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.218-224
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• 2001

To find out the optimum level of slow release N fertilizers (MS 10, MS S10, LCU 80, and LCU 100), total amount of nitrogen required throughout the growing season were applied in the seedling box or incorporated into paddy soil. Four levels of the slow release N fertilizers (0, 6, 9 and 12 kg N/10 a) were mixed with commercial rice nursery bed soil. N release rate and electrical conductivity(EC) of the slow release fertilizers were greater in the order of MS 10 > LCU 80 ${\fallingdotseq}$ LCU 100 > MS S10 and higher as temperature increased. No seedlings were emerged in all MS 10 plots. The seedling emergence rate of LCU 80 and LCU 100 decreased as the N level increased and seedlings were wilted severely on the 13th day after sowing at 9 and 12 kg N/10 a. In MS S10 plots the emergence rate was higher than 80% at all N levels and seedling growth was normal until 30 days after sowing. Yield of rice was similar between seedling box application and soil incorporation in paddy of MS S10. Yield of rice among the 6, 9, 12 kg N/10 a of MS S10 and conventional 12 kg N/10 a of urea split application was similar, but it was significantly higher compared with no N plot. Fertilizer N recovery of MS S10 decreased as fertilizer level increased and it was significantly higher compared with conventional urea split application.

• Korean Journal of Medicinal Crop Science
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• v.12 no.4
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• pp.295-299
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• 2004

This study was carried out to examine seed characteristics of Artemisia capillaris and the effects of different temperature and light on its seed germination, and of sowing date on its growth and yield. A seed of A. capillaris, 0.79 mm in length diameter, 0.39 mm in width diameter and 0.054 g in thousand-kernel weight, was extremely small, vertical pinstripes in the surface of seed, and long oval of dark brown in shape, and its maturity occurred September to October. A germination rate was superior at light conditions and 20 to $25^{\circ}C$ in temperature. Although its germination became shorter as the higher temperature. Its emergence rate was the highest in sowing at March 30. But the growth and yield potential was the best when sowed at March 20. The earlier the sowing date, the higher yield.