• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.1
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• pp.23-29
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• 2018

'Dakyeong' (Avena sativa L.), a winter oats for forage use, was developed by the breeding team at National Institute of Crop Science, RDA in 2016. It was derived from a cross between 'CI7505'(IT133304) and 'Swan'(IT197920). Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Iksan and Jeonju, respectively. After preliminary and advanced yield test for 2 years, 'SO2004009-B-B-10-8-3-9', designated as a line name of 'Gwiri91', were subsequently evaluated for earliness and forage yield during 3 years in four parts such as Jeju (upland), Yesan (upland), Iksan (upland), and Jeonju (paddy), from 2014 to 2016, and finally named as 'Dakyeong'. Cultivar 'Dakyong' has leaves of dark green color, thick diameter culm and long grain of brown color. Over 3 years, the heading date of 'Dakyeong' was about 5 days earlier than that of check cultivar 'Samhan' (April 30 and May 5, respectively), and their average forage dry matter yield harvested at milk-ripe stage was higher 12% ($15.7tone\;ha^{-1}$) than $14.0tone\;ha^{-1}$ of check cultivar. Cultivar 'Dakyeong' was lower than the check cultivar 'Samhan' in terms of the protein content (6.1% and 7.0%, respectively) and total digestible nutrients (62.1%, and 62.5%, respectively), while the TDN yield was more than the check ($7.79tone\;ha^{-1}$ and $7.64tone\;ha^{-1}$, respectively). Fall sowing cropping of 'Dakyeong' is recommended only in areas where average daily minimum mean temperatures in January are higher than $-6^{\circ}C$, and it should not be cultivated in mountain areas, where frost damage is likely to occur.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.1
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• pp.16-22
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• 2018

Oats (Avena sativa L.), which are known as one of the forage crops of Korea, have good livestock palatability and are popular to cattle farmers because of their high dry matter. However, the cultivation of double cropping in the rice field was reluctant due to the late maturing for farmers to plant rice continuously. 'Hi-early', a winter oats for forage use, was developed by the breeding team at National Institute of Crop Science, RDA in 2016. It was derived from a cross between '517A2-121'(IT133383) and 'CI7604' (IT133379). Subsequent generations followed by the cross were handled in bulk and pedigree selection programs at Suwon, Iksan and Jeonju, respectively. After preliminary and advance yield test for 2 years, 'SO2004015-B-B-23-1-3-7', designated as a line name of 'Gwiri92', were subsequently evaluated for earliness and forage yield during 3 years in four parts such as Jeju (upland), Yesan (upland), Iksan (upland), and Jeonju (paddy), from 2014 to 2016, and finally named as 'Hi-early'. Cultivar 'Hi-early' has the characteristics of medium leaves of green color, thick diameter culm, and medium grain of brown color. Over 3 years, the heading date of 'Hi-early' was about 9 days earlier than that of check cultivar 'Samhan' (April 26 and May 5, respectively). Average forage fresh yield of 'Hi-early' harvested at milk-ripe stage was similar to check cultivar ($40.2tone\;ha^{-1}$ and 40.0 tone ha-1, respectively), and dry matter yield also was similar to check cultivar (14.2 tone ha-1 and $14.0tone\;ha^{-1}$, respectively). Cultivar 'Hi-early' was lower than the check cultivar 'Samhan' in terms of the protein content (6.2% and 7.0%, respectively) and total digestible nutrients (61.0%, and 62.5%, respectively), while the TDN yield was more than the check ($7.91tone\;ha^{-1}$ and $7.64tone\;ha^{-1}$, respectively). Fall sowing cropping of 'Hi-early' is recommended only in areas where average daily minimum mean temperatures in January are higher than $-6^{\circ}C$, and it should not be cultivated in mountain areas, where frost damage is likely to occur.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.219-226
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• 1976

To meet the need of protein feed and fine more efficient ways of returning waste to resources, we have carried out the study of the production of yeast for foods and feeds from the corn starch cake. The present study includes the method for acid-hydrolysis, the selection of yeast capable of utilizing hydrolyzate of the corn starch cake, and culture condition of Candida tropicalis under the liquid culture and the semisolid culture. Obtained results were as follows. 1. Hydrochloric acid was more excellent on the hydrolysis of the corn starch cake than sulfuric acid, and the yield of sugar was maximum, 57.2%, when the corn starch cake was hydrolyzed with 1.0% of hydrochloric acid at 2.0kg/cm for 30 minutes. 2. As the acid solution content was increased, more sugar was liberatedfrom the mixture, until the acid solution-substrate ratio reached 10:1. Beyond this point, no further increase was observed. To prepare the cultural medium of semisolid fermentation, a acid solution to substrate ratio of 3:1 appeared to be optimum. 3. Out of 6 yeast strains, Candida tropicalis had excellent growth on the hydrolyzate of the corn starch cake, and optimum temperature and initial pH were $30^{\circ}C$ and 6.0 respectively. 4. Optimum liquid medium of Candida tropicalis is ures 0.3%, potassium phosphate monobasic 0.15g and magnesium sulfate 0.04g in 100ml of the hydrolyzate of the corn starch cake, while optimum semisolid medium is ammonium chloride 0.4g, potassium phosphate monobasic 0.1%, magnesium sulfate 0.04%. 5. Candida tropicalis could assimilate the sugar in the hydrolyzate up to more than 88.75%, and a yield of dry yeast reached 19.13% to the corn starch cake under the liquid culture. 6. Compared to the that of the untreated corn starch cake, the cellulose content of the semisolid fermented cake decreased by 3.76% to 14.7%, whereas dry yeast contents increased by 13.89%.

• Radiation Oncology Journal
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• v.22 no.2
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• pp.77-90
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• 2004

Purpose: The purpose of this review Is to provide an update on novel radiation treatments for head and neck cancer Recent Findings: Despite the remarkable advances In chemotherapy and radiotherapy techniques, the management of advanced head and neck cancer remains challenging. Epidermal growth factor receptor (EGFR) Is an appealing target for novel therapies In head and neck cancer because not only EGFR activation stimulates many important signaling pathways associated with cancer development and progression, and importantly, resistance to radiation. Furthermore, EGFR overexpression Is known to be portended for a worse outcome in patients with advanced head and neck cancer. Two categories of compounds designed to abrogate EGFR signaling, such as monoclonal antibodies (Cetuxlmab) and tyrosine kinase inhibitors (ZD1839 and 051-774) have been assessed and have been most extensively studied In preclinical models and clinical trials. Additional TKIs In clinical trials include a reversible agent, Cl-1033, which blocks activation of all erbB receptors. Encouraging preclinical data for head and neck cancers resulted In rapid translation Into the clinic. Results from Initial clinical trials show rather surprisingly that only minority of patients benefited from EGFR inhibition as monotherapy or In combination with chemotherapy. In this review, we begin with a brief summary of erbB- mediated signal transduction. Subsequently, we present data on prognostic-predictive value of erbB receptor expression in HNC followed by preclinlcal and clinical data on the role of EGFR antagonists alone or in combination with radiation In the treatment of HNC. Finally, we discuss the emerging thoughts on resistance to EGFR biockade and efforts In the development of multiple-targeted therapy for combination with chemotherapy or radiation. Current challenges for investigators are to determine (1 ) who will benefit from targeted agents and which agents are most appropriate to combine with radiation and/or chemotherapy, (2) how to sequence these agents with radiation and/or cytotoxlc compounds, (3) reliable markers for patient selection and verification of effective blockade of signaling in vivo, and (4) mechanisms behind intrinsic or acquired resistance to targeted agents to facilitate rational development of multi-targeted therapy, Other molecuiar-targeted approaches In head and neck cancer were briefly described, Including angloenesis Inhibitors, farnesyl transferase inhibitors, cell cycle regulators, and gene therapy Summary: Novel targeted theraples are highly appealing in advanced head and neck cancer, and the most premising strategy to use them Is a matter of intense Investigation.

• Food Science and Preservation
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• v.23 no.6
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• pp.797-803
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• 2016

In this study, we investigated the effect of fermentation conditions on the amylolytic and proteolytic activities of Aspergillus luchuensis strain 74-5 and Aspergillus oryzae strain 75-2, which are used in the preparation of the starter culture, for Takju (Korean traditional rice wine). The starter culture was optimized using different conditions, such as inoculum size, inoculation temperature, and incubation time. The enzyme activities under each condition were measured. In the A. luchuensis strain 74-5 starter culture, the ${\alpha}-amylase$ and glucoamylase activities increased, however the activity of acidic protease decreased as the diluent to starter culture ratio increased. In the A. oryzae 75-2 starter culture, all enzyme activities were maintained at a higher level even at 5% inoculation ratio. Higher enzyme activities were observed in the middle range of inoculation temperature (35, $40^{\circ}C$), than in the lower range (20, $30^{\circ}C$). Enzyme activity in the starter culture varied with incubation time, however it was the highest at 144 and 120 hr, respectively, for A. luchuensis strain 74-5 and A. oryzae strain 75-2. The spore count of the starter culture was approximately $2{\times}10^7$ during fermentation, out of which contamination by aerobic bacteria was about $3{\times}10^3$. The results suggested that the starter culture of each strain could be used as an inoculum for fermentation. However, we needs to conduct further research for the selection of suitable diluting agents as well as drying methods to reduce the contamination by aerobic bacteria, while retaining the enzyme activity.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.333-343
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• 2015

This research aims at identifying the goshawk's possible and replaceable breeding ground by using the MaxEnt prediction model which has so far been insufficiently used in Korea, and providing evidence to expand possible protection areas for the goshawk's breeding for the future. The field research identified 10 goshawk's nests, and 23 appearance points confirmed during the 3rd round of environmental research were used for analysis. 4 geomorphic, 3 environmental, 7 distance, and 9 weather factors were used as model variables. The final environmental variables were selected through non-parametric verification between appearance and non-appearance coordinates identified by random sampling. The final predictive model (MaxEnt) was structured using 10 factors related to breeding ground and 7 factors related to appearance area selected by statistics verification. According to the results of the study, the factor that affected breeding point structure model the most was temperature seasonality, followed by distance from mixforest, density-class on the forest map and relief energy. The factor that affected appearance point structure model the most was temperature seasonality, followed by distance from rivers and ponds, distance from agricultural land and gradient. The nature of the goshawk's breeding environment and habit to breed inside forests were reflected in this modeling that targets breeding points. The northern central area which is about $189.5 km^2$(2.55 %) is expected to be suitable breeding ground. Large cities such as Cheongju and Chungju are located in the southern part of Chungcheongbuk-do whereas the northern part of Chungcheongbuk-do has evenly distributed forests and farmlands, which helps goshawks have a scope of influence and food source to breed. Appearance point modeling predicted an area of $3,071 km^2$(41.38 %) showing a wider ranging habitat than that of the breeding point modeling due to some limitations such as limited moving observation and non-consideration of seasonal changes. When targeting the breeding points, a specific predictive area can be deduced but it is difficult to check the points of nests and it is impossible to reflect the goshawk's behavioral area. On the other hand, when targeting appearance points, a wider ranging area can be covered but it is less accurate compared to predictive breeding point since simple movements and constant use status are not reflected. However, with these results, the goshawk's habitat can be predicted with reasonable accuracy. In particular, it is necessary to apply precise predictive breeding area data based on habitat modeling results when enforcing an environmental evaluation or establishing a development plan.

• Korean Journal of Environment and Ecology
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• v.24 no.2
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• pp.209-221
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• 2010

This study was carried out to apply basic data of the native trees for planting in the salinity area by the vegetation ecological selection. Which focused on native woody species to the tolerances of saline soil and salt spray drift on the coastal forests in the West-Sea, Korea. The soil salinity($EC_{1:5}$) was 0.11dS$m^{-1}$, ranging of 0.00dS$m^{-1}$~0.68dS$m^{-1}$. The soil salinity was gradually decreasing from Belt I to Belt Ⅳ except the Belt I in some coastal windbreaks. The order of decreasing soil salinity was Belt I>Belt II>Belt III>Belt Ⅳ and the soil salinity was $EC_{1:5}$ 0.14dS$m^{-1}$, 0.11dS$m^{-1}$, 0.10dS$m^{-1}$, and 0.08dS$m^{-1}$, respectively. The total 181 taxa consisted of 52 families, 104 genus, 157 species, and 24 varieties were recorded as the trees tolerating to both soil salinity and salt spray drift. The trees emerged in the highest degree of salinity($EC_{1:5}$ 0.51dS$m^{-1}$) was nothing but appearanced Pinus thunbergii Parl., Smilax china L., Quercus dentata Thunb. ex Murray, Quercus serrata Thunb. ex Murray and so on at the level of singular and ideal value. The emerged trees in the high salinity of $EC_{1:5}$0.41dS$m^{-1}$~0.50dS$m^{-1}$ were Albizia kalkora Prain, Melia azedarach L., Paederia scandens (Lour.) Merr. var. scandens These species were trees of tolerance to saline soil. The emerged woody species in all belts were Pinus rigida Mill., Pinus densiflora Siebold & Zucc., Pinus thunbergii Parl., Juniperus rigida Siebold & Zucc. and so on. The woody species with high important value(I.V.) were Pinus densiflora Siebold & Zucc., Pinus thunbergii Parl., Pseudosasa japonica (Siebold & Zucc. ex Steud.) Makino, Smilax china L., Platycarya strobilacea Siebold & Zucc. var. strobilacea for. strobilacea and so on, which can be classified as highly tolerant native trees to salt spray drift.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.96-106
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• 2008

The purpose of this study was to identify the actual conditions of operation in school and investigate the perceptions of science teachers and students regarding the 7th elective-centered curriculum of high school science subjects. For this study, a questionnaire survey was conducted for the selected subjects including 127 high school science teachers and 763 high school students in their third year who had experienced the 7th elective-centered curriculum. As a result of the study, concerning the way to present the elective subjects of science, many cases were the alternative way and the group-elective way in humanity courses while natural science courses had the alternative way and the free-elective way in most cases. In other words, in many cases, the right of elective was given within a limited range. The result of the investigation on science teachers' perceptions on the elective-centered curriculum was that negative views dominated as a whole. Especially, earth science teachers showed the most negative attitudes. The number of biology and chemistry teachers who supported students' right to opt subjects were lower than that of physics teachers and earth science teachers who were against it. To help students make a right choice, many viewed that the system of the college Scholastic Ability Test should be complemented in order to prevent any disadvantage to each elective subject or that it was necessary to have systematic and realistic career education. As the result of investigating the perception of high school students in their third year regarding the elective-centered curriculum, they were usually not very satisfied with it. As the reason for it, many said the selection right was limited. Many others also expressed that there were lack of public relations and education on subjects and careers. Based on these results, limits still exist in accepting all demands although there are a lot of efforts made to smoothly adjust supply and demand of science teachers as well as students' electives in the field of school. It is considered necessary to come up with counterplan and complements to prevent basic science from being neglected or lower academic achievement in the subject of science from happening, and at the same time to harmoniously deal with supply and demand of science teachers as well as the issues of students' demands given the actual conditions of school.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.169-175
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• 1980

These studies were conducted to induce the available mutant strains in acetic acid bacteria by the irradiation of UV-light and the treatment of N-methyl-N'-nitro-N'-nitrosoguanidine. 109 strains which were capable of producing acid in the ethanol containing medium were isolated from vinegar and Kimchi collected from the region of Daejeon city. From the collection T-50 strain was identified to have a strong fermentation power and selected as a mother strain for the study. Two mutants were obtained by treating T-50 strain with UV and NTG, and these mutants had a rapid acid production in the initial stage. The study was then made to compare the basic condition for acetic acid production of the mother strain and two mutant strains. The summarized results were as follows; 1. The isolated strain (T-50) was identified as Acetobacter aceti by Bergey's manual and Acetic acid bacteria (Tokyo Univ. press). 2. The selected strain was died completely when the strain was irradiated with 15 W UV-light at a distance of 45 cm for 160 seconds. 3. The mutants such as U-48 and N-67 were rapid in the acetic acid production at the initial stage compare to the mother strain. 4. Acetic acid formation by the shaking culture method was maximized in 2 days culture, and the optimal temperature for acetic acid production was $30^{\circ}C$. 5. Acetic acid was effectively produced by the addition of 0.1% ammonium sulfate as a nitrogen source and was also produced rapidly by the addition of 0.1% glucose.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.207-212
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• 2016

This work was carried out to investigate the ability of thirteen crossbreds for production of commercial chicken (CC) of Korean native chicken to be cut out for Korean circumstance. Total of one thousand three hundred of crossbreds were divided thirteen groups (100 birds/group) that were twelve groups (1A, 1B, 2A, 2B, 3A, 3B, 4A, 4B, 5A, 5B, 6A, 6B) to crossbreed with two sires (A, B) and six dams (1, 2, 3, 4, 5, 6) of parent stock (PS) of Korean native chicken and one group (HH) as commercial Korean native chicken. Experimental diets were starter diet (0~7d; CP 22.0% ME 3,150 kcal/kg), early diet (8d~Wt 800 g; CP 19.0% ME 3,150 kcal/kg) and finished diet (Wt 800 g~12 wk; CP 18.0% ME 3,150 kcal/kg). Fertility of 1B group was higher than other groups. Hatchability per fertilization eggs and hatchability per setting eggs were 87.5~89% and 87.9~96.3%, respectively, and those of 4B and 6B groups were lower compared to other groups. Weekly body weight of HH group was lower than other groups. CV values of body weight of thirteen groups were showed over 12% as 12.5~18.2%, and especially, those of 2B, 3B, 5B, HH groups were lower compared to other groups. Weekly feed conversion ratios (FCRs) of 13 crossbreds were 1.7~2.3, 2.1~2.5, 2.4~2.7 and 2.7~3.2 at the age of 6, 8, 10 and 12 weeks, respectively. Weekly production indexes of 2A, 3A and HH groups were the lower than other groups and those of thirteen groups decreased following weeks. Feed costs per body weight gain (kg) were 1,069~1,255 won, 1,100~1,263 won, and 1.468~1,696 won at starter, earlier and finished period of broilers. These results leaded down to conclusion to be possible selection of new Korean native commercial chicken that have the excellent performance and economics.