• Title/Summary/Keyword: Late effect

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Direct Intratumoral Injection of Ethanol in the Patients with Obstruction of Major Bronchus (주기관지 폐색환자에서 종양내 ETHANOL 주입치료 효과)

  • Lee, Bong-Chun;Yum, Ho-Kee;Choi, Soo-Jeon;Kim, Dong-Soon
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.5
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    • pp.495-500
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    • 1993
  • Background: For the relief of the occlusion of major bronchi, laser therapy, radiation therapy or combined therapy is generally used. But the effect of radiation therapy is very slow and not consistent and laser therapy requires expensive equipments and technical expertise with occasional serious side effects. Direct ethanol injection has been widely used for the control of bleeding in gastrointestinal lesion, esophageal varices or renal cell carcinoma with good results. So we tried direct injection of ethanol into the tumor to relieve the obstruction of major bronchus in 11 patients. Method: All procedures were done under the fiberoptic bronchoscopy with continuous oxygen supplement and aliquoted 0.5-1.0 ml of absolute ethanol directly into the tumor through the endobronchial aspiration needle. The tumor was endoscopically removed with a biopsy forceps immediately after ethanol injection. The whole procedure was repeated 3-4 days interval until the lumen opens. Usually after 2-3 trials of ethanol injection, the lumen opened up. Results: The immediate effect of ethanol injection was whitening of the mucosa and prompt cessation of bleeding. The late effect was necrosis of the tumor. The final results of this procedure were improvement of symptoms and reexpnasion of the lung in all patients. $FEV_{1.0}$ and FVC were improved and $PaO_2$ was increased from $68.1{\pm}9.2$ mmHg to $83.9{\pm}8.1$ mmHg, $SaO_2$: from $94{\pm}8.5%$ to $96.6{\pm}1.1%$, and $AaDO_2$ was reduced from $26.5{\pm}8.5$ mmHg to $10.9{\pm}9.1$ mmHg. Conclusion: Direct ethanol injection into the tumor tissue is a rapid, cheap and relatively safe method of relieving the complete occlusion of major bronchus.

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Effect of the Elevated Temperature on the Growth and Physiological Responses of Peach 'Mihong' (Prunus persica) (온도 상승처리가 복숭아 '미홍'의 수체생육 및 생리반응에 미치는 영향)

  • Lee, Seul Ki;Cho, Jung Gun;Jeong, Jae Hoon;Ryu, Suhyun;Han, Jeom Hwa;Do, Gyung-Ran
    • Journal of Bio-Environment Control
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    • v.29 no.4
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    • pp.373-380
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    • 2020
  • This study was conducted to investigate the effect of elevated temperatures on the growth and physiological responses of peach 'Mihong' (Prunus persica). We simulated three different temperature conditions in the sunlight phytotron rooms from April 25 to July 5, 2019; Control (average temperature in normal years in Jeonju city), +3.4℃ treatment (expecting temperature in mid-21st century), +5.7℃ treatment (expecting temperature in late 21st century). The shoot numbers and lengths were increased while the temperature was increased, but the leaf areas were not statistically different. The harvest dates were July 1, June 24 and 21 at the control, +3.4℃, and +5.7℃, respectively. The fruit weights were increased at +3.4℃ but decreased at +5.7℃ compared to the control. The tree yield was the highest in the +3.4℃ (2,898g), followed by the control (2,746g) and the +5.7℃ (2,404g). These are related to the result that the average of maximum photosynthesis rate at 3.4℃ (14.93μmol·CO2·m-2·s-1) was higher than those at the control (13.79μmol·CO2·m-2·s-1) and +5.7℃ (13.20μmol·CO2·m-2·s-1) from mid-May to early June, the fruit growing season. Also, the stomatal densities were higher at the +3.4℃ (229ea/㎟), compared to the control (181ea/㎟). The rate of floral bud differentiation affecting the yield in the following year was the lowest at the +5.7℃. These results suggest that a temperature elevated to 3.4℃ in the future may give a positive effect on the yield and quality of peach 'Mihong' while a temperature elevated above 5.7℃ may affect negatively.

Effect of Epidermal Growth Factor on In Vitro Maturation in Pig Immature Oocytes;IV. Effect of Epidermal Growth Factor on In Vitro Development (Epidermal Growth Factor가 돼지 미성숙난포란의 체외성숙에 미치는 영향;IV. 체외 배발달에 미치는 Epidermal Growth Factor의 효과)

  • Uhm, S.J.;Kim, E.Y.;Kim, M.K.;Kim, T.;Yoon, S.H.;Park, S.P.;Chung, K.S.;Lim, J.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.23 no.3
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    • pp.303-310
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    • 1996
  • The objective of this study was to examine the effect of embryos development following IVF of in vitro-matured porcine oocytes treated with epidermal growth factor (EGF). When cumulus-enclosed oocytes were incubated in TCM 199 medium supplemented with (1) control group, (2) 10 ng/ml EGF, (3) 10${\mu}g$ml FSH and 10% FBS, or (4) 10 ng/ml EGF, 10 ${\mu}g$/ml FSH, and 10% FBS for 42 hr, the late developmental rates on NCSU (0.4% BSA) medium after fertilization were higher in (3) and (4) groups (13.4, 18.3%) than in (2) group (5.2%, p < 0.005), but (2) group is significantly higher than the development to blastocyst of oocytes of (1) group (1.2%). Also, when the cell number of total, ICM, and TE of those blastocysts at 6 day produced in vitro was investigated by double staining (PI and bisbenzimide), total cell number of (4) group (58.80${\pm}$ 11.90) was higher than that of (2) and (3) groups (42.17${\pm}$9.97, 49.07${\pm}$9.77, P < 0.05). ICM cell number of blastocysts of (4) group (11.69${\pm}$5.56) was higher than that of (2) and (3) groups (5.00${\pm}$4.24, 6.77${\pm}$4. 92, P < 0.05). Furthermore, the proportion of ICM in (4) group (19.0${\pm}$1.6) was higher than that in (2) and (3) groups (11.1${\pm}$3.0, 12. 7${\pm}$2.1). These results suggested that in vitromatured porcine oocytes treated with EGF alone can be developed to blastocyst, but high proportion on the development to blastocyst and number of total cell and ICM in blastocyst can be obtained when supplemented with additional FSH and FBS.

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Effect of Various Nitrogen Fertilizers on Rice Yield in Direct Seeding on Dry Paddy (건답 직파재배 논에서 질소비료 형태에 따른 시용효과)

  • Park, Chol-Soo;Jung, Yeong-Sang;Lee, Ho-Jin;Joo, Jin-Ho;Seo, Jun-Han
    • Korean Journal of Soil Science and Fertilizer
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    • v.33 no.5
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    • pp.318-324
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    • 2000
  • Field experiment was conducted on a sandy clay loam paddy field in the Experimental Farm of the Kangwon National University for four years from 1995 to 1998 to evaluate the effect of different nitrogen fertilizers on soil property and rice yield. The size of each experimental plot was 75 m2. Basal application of fertilizer to the paddy field was on late April, and rice (cv. Odae) was sown with drill seeding on early May. Irrigation was done at 3 leaf stages after rice seeding. Electrical conductivity in soils treated with phosphate- and resin coated slow release fertilizers were relatively greater than those of the other fertilizer application. Available $P_2O_5$ concentration in soils after rice harvest increased significantly compared that in soil before field trial. Rice yield in transplanting culture were $6.516kg\;ha^{-1}$. The rice yield in the direct seeded paddy was 81.9 percents of the yield in the transplanted paddy. The rice yield in phosphate coated slow release fertilizer was the highest among various fertilizer trials in directly seeded dry paddy, while rice yield was the lowest in the organic fertilizer plus urea application. Rice yield between organic fertilizer plus urea and organic fertilizer application were not significantly different. The green manuring effect of rye in the direct seeded rice paddy in Chuncheon was low due to low temperature and short growth period.

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Modeling the Effect of a Climate Extreme on Maize Production in the USA and Its Related Effects on Food Security in the Developing World (미국 Corn Belt 폭염이 개발도상국의 식량안보에 미치는 영향 평가)

  • Chung, Uran
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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    • 2014.10a
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    • pp.1-24
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    • 2014
  • This study uses geo-spatial crop modeling to quantify the biophysical impact of weather extremes. More specifically, the study analyzes the weather extreme which affected maize production in the USA in 2012; it also estimates the effect of a similar weather extreme in 2050, using future climate scenarios. The secondary impact of the weather extreme on food security in the developing world is also assessed using trend analysis. Many studies have reported on the significant reduction in maize production in the USA due to the extreme weather event (combined heat wave and drought) that occurred in 2012. However, most of these studies focused on yield and did not assess the potential effect of weather extremes on food prices and security. The overall goal of this study was to use geo-spatial crop modeling and trend analysis to quantify the impact of weather extremes on both yield and, followed food security in the developing world. We used historical weather data for severe extreme events that have occurred in the USA. The data were obtained from the National Climatic Data Center (NCDC) of the National Oceanic and Atmospheric Administration (NOAA). In addition we used five climate scenarios: the baseline climate which is typical of the late 20th century (2000s) and four future climate scenarios which involve a combination of two emission scenarios (A1B and B1) and two global circulation models (CSIRO-Mk3.0 and MIROC 3.2). DSSAT 4.5 was combined with GRASS GIS for geo-spatial crop modeling. Simulated maize grain yield across all affected regions in the USA indicates that average grain yield across the USA Corn Belt would decrease by 29% when the weather extremes occur using the baseline climate. If the weather extreme were to occur under the A1B emission scenario in the 2050s, average grain yields would decrease by 38% and 57%, under the CSIRO-Mk3.0 and MIROC 3.2 global climate models, respectively. The weather extremes that occurred in the USA in 2012 resulted in a sharp increase in the world maize price. In addition, it likely played a role in the reduction in world maize consumption and trade in 2012/13, compared to 2011/12. The most vulnerable countries to the weather extremes are poor countries with high maize import dependency ratios including those countries in the Caribbean, northern Africa and western Asia. Other vulnerable countries include low-income countries with low import dependency ratios but which cannot afford highly-priced maize. The study also highlighted the pathways through which a weather extreme would affect food security, were it to occur in 2050 under climate change. Some of the policies which could help vulnerable countries counter the negative effects of weather extremes consist of social protection and safety net programs. Medium- to long-term adaptation strategies include increasing world food reserves to a level where they can be used to cover the production losses brought by weather extremes.

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The Effect of Low Concentrated Hypoxanthine and FSH in 10% FBS Supplemented Medium on Immature Oocyte in vitro Maturatio (낮은 농도의 Hypoxanthine과 FSH가 미성숙난자의 체외성숙에 미치는 영향)

  • Han, Hyuck-Dong;Lim, Chang-Kyo;Youm, Hyun-Sik;Hyon, Naomi Na-Hyoung;Lee, Ji-Hyang;Hong, Me
    • Clinical and Experimental Reproductive Medicine
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    • v.36 no.3
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    • pp.175-186
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    • 2009
  • Objective: We examined the effect of different culture media on oocyte maturation. Methods: Four groups of media, (1) 0.3% BSA mBASAL-XI-HTF, (2) 0.3% BSA mBASAL-XI-HTF with FSH, (3) 10% FBS mBASAL-XI-HTF and (4) 10% FBS mBASAL-XI-HTF with FSH were prepared. Mouse cumulus enclosed oocytes (CEOs) were incubated in each group of medium. Hypoxanthine (Hx) was mixed to each group of medium in increasing concentrations of 1 mM, 2 mM and 4 mM. CEOs were incubated and assessed for GVBD and MII development at 3, 6, 18 hours. Results: CEOs maturation to GVBD was seen in all four groups during 3 hours of culture, however MII stage of oocytes was seen after 6 hours. Complete arrest of GV stage in 4 mM Hx media without FSH and partial arrest in 2 mM Hx media without FSH were seen during 18 hours of culture but development was not suppressed in 1 mM Hx media without FSH. More prominent GVBD suppression was noted at early 3, 6 hours culture in 1 mM, 2 mM Hx media with FSH compared to media without FSH. But the suppression was recovered at 18 hours. This result suggests that low concentrated Hx and FSH supplemented media can suppress CEOs maturation during early culture period but recovery is resumed or even stimulated at late period. 1 mM, 2 mM Hx 10% FBS medium with FSH had significantly higher rates of MII development (71.7%, 66.7%) at 18 hours compared to other media. Conclusion: Our results show that low concentrated Hx and FSH supplemented 10% FBS media may stimulate MII development after an initial inhibitory effect.

Study on Material Characteristics and Conservation Methods for Tracksite of Cretaceous Dinosaurs and Pterosaurs of Jeongchon area in Jinju, Korea (진주 정촌면 백악기 공룡·익룡발자국 화석산지의 재질특성 및 보존 방안 연구)

  • Ji Hyun Yoo;Yu Bin Ahn;Myoung Nam Kim;Myeong Seong Lee
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.697-714
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    • 2023
  • The Tracksite of Cretaceous Dinosaurs and Pterosaurs in Jeongchon, Jinju was discovered in late 2017 during the construction of the Ppuri industry complex. This site is a natural heritage site with a high paleontological value, as it preserves fossils of various types of dinosaurs, pterosaurs, and animal traces at a dense concentration. In this study, we surveyed that physical weathering such as joint, crack, scaling, exfoliation, and fragmentation occurred through field research in the fossil site, and conducted basic research on conservation science to reduce the damage. To this end, among the eight levels identified after excavation, the rocks of Level 3, which yielded a large number of theropod footprint fossils, and Level 4, which yielded pterosaur footprint fossils, were analyzed for material characteristics and evaluation of the effectiveness of consolidation and adhesion. This results showed that the rocks in the Level 3 stratum were dark gray siltstone and the rocks in the Level 4 stratum were dark gray shale, which contained a large amount of calcite and were composed of quartz, plagioclase, mica, alkali feldspar, and other clay minerals, which are likely to be damaged by rainfall under external conditions. As a result of conducting an artificial weathering experiment by dividing the probationary sample into four groups: untreated, consolidation treatment, anti-swelling treatment, and adhesive treatment, the consolidation and the swelling inhibitor showed an effect immediately after treatment, but did not show a blocking effect under a freezing-thawing environment. The adhesive showed that the adhesive effect was maintained even under freezing-thawing conditions. In order to preserve the fossil sites at Jeongchon in the future, in addition to temporary measures to block the inflow of moisture, practical measures such as the construction of protective facilities should be prepared.

The Structural Relationships between Control Types over Salespeople, Their Responses, and Job Satisfaction - Mediating Roles of Role Clarity and Self-Efficacy - (영업사원에 대한 통제유형, 반응, 그리고 직무만족 간의 구조적 관계 - 역할명확성과 자기효능감의 매개효과 -)

  • Yoo, Dong-Keun;Lim, Jong-Koo;Lim, Ji-Hoon
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.4
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    • pp.23-49
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    • 2007
  • Salespeople act at the point of MOT with customers and deliver the enterprise's message to the customers. They build up relationships with customers as well as deliver the customer's message to the enterprise. The salespeople's activity at the point of MOT with the customers and the degree of satisfaction of the customers' needs will affect the customers' attitude toward the enterprise, brand loyalty, and retention intention. Ultimately, it will influence the enterprise's financial performance. The control of salespe1ople is one of the most interesting topics of marketing. This research investigates the relationships of the control types over salespeople(positive/negative outcome control, positive/negative behavior control) and job satisfaction and their mediating variables. The mediating variables in the relationships have been identified as outcome/behavior-related role clarity and self-efficacy. The purpose of this study is more specifically as follows: First, it investigate how the perception of salespeople control types affect role-clarity. Second, it examines how the perception of salespeople control types influence self-efficacy. Third, it investigate the mediating role of role-clarity between the perception of salespeople control types and self-efficacy. Fourth, it investigates how role-clarity affect self-efficacy and job satisfaction. Finally, it will investigates how self-efficacy influences job satisfaction. Data were collected from the pharmaceutical industry salespeople and analyzed by SPSS 12.0 and AMOS 6.0. The data were collected by 400 respondents and 377 valid questionnaires were analyzed. The results are summarized as follows: First, positive/negative outcome controls had a positive relationship with outcome-related role clarity. Also positive behavior control had a positive effect on behavior-related role clarity, but negative behavior control didn't influence behavior-related role clarity. Second, positive outcome control influenced self-efficacy positively, but positive behavior control didn't have a positive effect on self-efficacy. In addition negative outcome control and negative behavior control had a positive effect on self-efficacy due to the mediating role of outcome-related and behavior-related role clarity. Third, outcome-related role clarity and behavior-related role clarity influenced self-efficacy positively. Behavior-related role clarity had a positive effect on job satisfaction, but outcome-related role clarity didn't influence job satisfaction. Finally, self-efficacy didn't have any effect on job satisfaction. The contributions of this study are as follows: First, existing studies have investigated the direct causal relationship between salespeoples' control type and performance, but this study investigates the structural causality between salespeoples' control types, responses, and performances. Second, this study found the mediating role of outcome-related/behavior-related role-clarity between outcome/behavior control and self-efficacy. Finally, the findings of this study further insight to existing studies on the relationship between job satisfaction and self-efficacy. The confidence of salespeoples' task influenced job satisfaction positively in existing articles,field studies, but the relationship between these two variables was not significant in this study. This means that there can be a different relationship between confidence and job satisfaction according to salespeoples' business. That is, the business environment may not be satisfying, even if the salespeople say that they have ability and confidence about their business. This means that able salespeople who have ability and confidence about their business are not satisfied with their job advancement in the company. Therefore, enterprise need to provide training that can establish a business environment that can satisfy the salespeole's expectation level which will secure good salespeople. This study may have limitation when applied to future studies. First,in this study as with existing studies it investigates the control level that salespeople feel is being measured. Actuality, the control level that a manager enforces and the control level that salespeople perceive when one is late can be different. There is need to measure lateness from both the perspective of the manager and salespeople should be done to supplement this study in the future Second, this study used variables that were connected with action result but salespeople's job satisfaction is due to the result of control. But, focusing on result of control can provide a more important financial result than sales performance. This study is also limited in that it did not consider financial result by result of control. Further studies on this will need to be done in the future. Third, this study may have a further limitation,because the investigation was restricted to pharmaceutical salespeople selling to hospitals. It is necessary to execute investigations in various industries to increase the generalization of the study findings Fourth, in this study, role clarity and self-efficacy by response variable for control and considered job satisfaction by outcome variable of control was considered. But, can other variables be considered beside response variable and result variable for control? For example, can financial affairs and change of post by outcome variable along with business stress by response variable for control be considered? Therefore, future studies need to consider various control variables. Finally, there is limited supporting research in the field of marketing which restricts the generalization of the study finding along with collecting material through random sampling of a limited size. This research summarizes the research in this area, the difference from the previous research, and provides a discussion of its limitations and the need and direction for further future research.

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Studies on Combining Ability and Inheritance of Major Agronomic Characters in Naked Barley (과맥의 주요형질에 대한 조합능력 및 유전에 관한 연구)

  • Kyung-Soo Min
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.2
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    • pp.1-24
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    • 1978
  • To obtain basic information on the breeding of early maturing, short culm naked-barley varieties, the following 10 varieties, Ehime # 1, Shikoku #42, Yamate hadaka, Eijo hadaka, Kagawa # 1, Jangjubaeggwa, Baegdong, Cheongmaeg, Seto-hadaka and Mokpo #42 were used in diallel crosses in 1974. Heading date, culm length and grain yield per plant for the parents, $F_1's$ and $F_2's$ of the 10X10 partial diallel crosses were measured in 1976 for analysis of their combining ability, heritability and inheritance. The results obtained are summarized below; 1. Heritabilities in broad sense for heading date, culm length and grain yield per plant were 0.7831, 0.7599 and 0.6161, respectively. Narrow sense heritabilities for heading date were 0.3972 in $F_1$ and 0.7789 in $F_2$ and for culm length 0.6567 in $F_1$ and 0.6414 in $F_2.$ These values suggest that earliness and culm length could be successfully selected for in the early generations. Narrow sense heritability for grain yield was 0.3775 in $F_1$ and 0.4170 in $F_2.$ 2. GCA effects of the $F_1$ and $F_2$ generations for days to heading were high in the early direction for early-heading varieties, while for late-heading varieties the GCA effects were high in the late direction. Absolute values for GCA effects in $F_1$ were higher than in $F_2.$ SCA effects of the $F_1$ and $F_2$ generations were high in the early-heading direction for Shikoku # 42 x Mokpo # 42, Ehime # 1 x Yamate hadaka, Shikoku # 42 x Yamate hadaka and Shikoku #42 x Eijo hadaka. 3. The GCA effects for culm length in the $F_1$ and $F_2$ generations for tall varieties were high in the tall direction while short varieties were high in the short direction. Absolute values for the GCA effects in $F_1$ were higher than in $F_2.$ SCA effects were high in the short direction for the combinations of Mokpo # 42 with Ehime # 1, Yamate had aka and Eijo hadaka. 4. The GCA effects for grain yields per plant in the $F_1$ and $F_2$ generations for varieties with high yields per plant were high in the high yielding direction, while varieties with low yields per plant were high in the low yielding direction. Absolute values of the $F_1$ GCA effects were higher than the $F_2$ effects. The combinations with high SCA effects were Mokpo # 42 x Shikoku # 42, Mokpo # 42 x Seto hadaka and Mokpo # 42 x Cheongmaeg. 5. Mean heading dates of the $F_1$ and $F_2$ generations were earlier than those of mean mid-parent. Mean heading date of the $F_1$ generation was earlier than the $F_2$ generation. Crosses involving early-heading varieties showed a greater $F_1, $ mid-parent difference than crosses involving late-heading varieties. 6. Heading date was controlled by a partial dominance effect. Nine varieties excluding Mokpo # 42 showed allelic gene action. Ehime # 1, Shikoku # 42, Kagawa # 1 and Mokpo # 42 were recessive to the other tested varieties. 7. The $F_2$ segregations of the 45 crosses for days to heading showed that 33 cosses were of such complexity that they could not be explained by simple genetic inheritance. One cross showed a 3 : 1 ratio where earliness was dominant. Another cross showed a 3 : 1 ratio where lateness was dominant. Four other crosses showed a 9 : 7 ratio for earliness while six crosses showed a 9 : 7 ratio for lateness. 8. Many transgressive segregants for earliness were found in the following crosses; Eijo hadaka x Baegdong, Ehime # 1 x Seto hadaka, Yamate had aka x Kagawa # 1, Kagawa # 1 x Sato hadaka, Shikoku # 42 x Kagawa # 1, Ehime # 1 x Kagawa # 1, Ehime # 1 x Shikoku # 42, Ehime # 1 x Eijo hadaka. 9. Mean culm length of the F, and F. generations were usually taller than the mid-parent where tall parent were used. These trends were high in the short varieties, but low in the tall varieties. 10. Culm length was controlled by partial dominace which was gonverned by allelic gene(s). Culm length showed a high degree of control by additive genes. Mokpo # 42 was recessive while Baegdong was dominant. 11. The F_2 frequency for culm length was in large part normally distributed around the midparent value. However, some combinations showed transgressive segregation for either tall or short culm length. From combinations between medium tall varieties, Ehime # 1, Shikoku # 42, Eijo hadaka and Seto hadaka, many short segregants could be found. 12. Mean grain yields per plant of the F_1 and F_2 generations were 6% and 5% higher than those of mid-parents, respectively. The varieties with high yields per plant showed a low rate of yield increase in their F_1's and F_2's while the varieties with low yields per plant showed a high rate of yield increase in their F_1's and F_1's. 13. Grain yields per plant showed over-dominnee effects, governed by non-allelic genes. Mokpo # 42 showed recessive genetic control of grain yield per plant. It remains difficult to clarify the inheritance of grain yields per plant from these data.

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Studies on the Environmental Factors Affecting the Cocoon Crops in Summer and Autumn in Korea (한국의 하추잠작 안정을 위한 환경요인에 관한 연구)

  • 이상풍
    • Journal of Sericultural and Entomological Science
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    • v.16 no.2
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    • pp.1-34
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    • 1974
  • These experiments pertain to various factors influencing the quantitative characters of cocoon crops in summer and early autumn seasons. Initially, in order to establish the possible ways of the silkworm rearing more than three times a year in Korea, the author attempted to get further information about the various factors affecting the cocoon crop in every silkworm rearing season. The trials were conducted eleven times a year at four places for three years. The field trial was conducted with 19 typical sericultural farmers who had been surveyed. At the same time the author statistically analyzed the various factors in close relation to tile cocoon crop in autumn season. The effect of guidance on 40 sericultural farmers was analyzed, comparing higher level farmers with lower level farmers ; and the author surveyed 758 non-guided farmers near the guided farmers during both spring and autumn seasons. In addition, another trial on the seasonal change of leaf quality was attempted with artificial diets prepared with leaves grown in each season. It was found that related factors to cocoon crops in summer and early autumn seasons appeared to be leaf quality, and temperature for young and grown larvae. A 2$^4$ factorial experiment was designed in summer season, and another design with one more level of varied temperature or hard leaf added to a 24 factorial experiment was conducted in early autumn. The experimental results can be summarized: 1. Study on the cocoon crops in the different rearing seasons 1) It was shown that earlier brushing of silkworm generally produced the most abundant cocoon crop in spring season, and earlier or later than the conventional brushing season, especially earlier brushing was unfavorable for the abundant cocoon crop in autumn season. 2) The cocoon crop was affected by the rearing season, and decreases in order of sire with spring, autumn, late autumn, summer and early autumn seasons. 3) It was Proved that ordinary rearing and branch rearing were possibles 4 times a year ; in the 1st, 3rd, 8th, and 10th brushing season. But the 11th brushing season was more favorable for the most abundant cocoon crop of branch rearing, instead of the 10th brushing season with ordinary rearing. 2. Study on the main factors affecting the cocoon crop in autumn season 1) Accumulated pathogens were a lethal factor leading to a bad cocoon crop through neglect of disinfection of rearing room and instruments. 2) Additional factors leading to a poor cocoon crop were unfavorable for rearing temperature and humidity, dense population, poor choice of moderately ripened leaf, and poor feeding techniques. However, it seemed that there was no relationship between the cocoon crop and management of farm. 3) The percentage of cocoon shell seemed to be mostly affected by leaf quality, and secondarily affected by the accumulation of pathogens. 3. Study on the effect of guidance on rearing techniques 1) The guided farms produced an average yearly yield of 29.0kg of cocoons, which varied from 32.3kg to 25.817g of cocoon yield per box in spring versus autumn, respectively. Those figures indicated an annual average increase of 26% of cocoon yield over yields of non-guided farmers. An increase of 20% of cocoon yield in spring and 35% of cocoon yield in autumn were responsible. 2) On guided farms 77.1 and 83.7% of total cocoon yields in the spring and autumn seasons, respectively, exceeded 3rd grade. This amounted to increases of 14.1 and 11.3% in cocoon yield and quality over those of non-guided farms. 3) The average annual cocoon yield on guided farms was 28.9kg per box, based on a range of 31.2kg to 26.9kg per box in spring and autumn seasons, respectively. This represented an 8% increase in cocoon yield on farms one year after guidance, as opposed to non-guided farms. This yield increase was due to 3 and 16% cocoon yield increases in spring and autumn crops. 4) Guidance had no effect on higher level farms, but was responsible for 19% of the increases in production on lower level farms. 4. Study on the seasonal change of leaf quality 1) In tests with grown larvae, leaves of tile spring crop incorporated in artificial diets produced the best cocoon crop; followed by leaves of the late autumn, summer, autumn, and early autumn crops. 2) The cocoon crop for young larvae as well as for grown larvae varied with the season of leaf used. 5. Study on factors affecting the cocoon crops in summer and early autumn A. Early autumn season 1) Survival rate and cocoon yield were significantly decreased at high rearing temperatures for young larvae 2) Survival rate, cocoon yield, and cocoon quality were adversely affected by high rearing temperatures for grown larvae. Therefore increases of cocoon quantity and improvement of cocoon quality are dependent on maintaining optimum temperatures. 3) Decreases in individual cocoon weight and longer larval periods resulted with feeding of soft leaf and hard leaf to young larvae, but the survival rate, cocoon yield and weight of cocoon shell were not influenced. 4) Cocoon yield and cocoon quality were influenced by feeding of hard leaf to grown larvae, but survival rate was not influenced by the feeding of soft leaf and hard leaf. 5) When grown larvae were inevitably raised at varied temperatures, application of varied temperature in the raising of both young and grown larvae was desirable. Further research concerning this matter must be considered. B. Summer season 1) Cocoon yield and single cocoon weight were decreased at high temperatures for young larvae and survival rate was also affected. 2) Cocoon yield, survival rate. and cocoon quality were considerably decreased at high rearing temperatures for grown larval stages.

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