• Korean Journal of Environmental Agriculture
• /
• v.30 no.4
• /
• pp.466-472
• /
• 2011

BACKGROUND: Soybean [Glycine max (L.) Merrill] is a legume and an important oil crop worldwide. This study was conducted to evaluate the possible impact of transgenic soybean cultivation on the soil microbial community. METHODS AND RESULTS: Microorganisms were isolated from the rhizosphere soils. Microbial community was identified based on the culture-dependent and molecular biology methods. The total numbers of bacteria, fungi, and actinomycete in the rhizosphere soils cultivated with transgenic and non-transgenic soybeans were similar to each other, and there was no significant difference between transgenic and non-transgenic soybeans. Dominant bacterial phyla in the rhizosphere soils cultivated with transgenic or non-transgenic soybeans were Actinobacteria, Firmicutes, and Proteobacteria. The microbial communities in transgenic and non-transgenic soybean soils were characterized using the denaturing gradient gel electrophoresis (DGGE). The DGGE profiles showed the different patterns, but didn't show significant difference to each other at 0.05 significance level. DNAs were isolated from soils cultivating transgenic or non-transgenic soybeans and analyzed for persistence of transgenes in the soil by using PCR. PCR analysis revealed that there were no amplified ${\gamma}$-tmt and bar gene in soil DNA. CONCLUSION(S): The results of this study suggested that microbial community of soybean field were not significantly affected by cultivation of the transgenic soybeans.

• Korean Journal of Comparative Education
• /
• v.27 no.1
• /
• pp.29-49
• /
• 2017

The purpose of this study is to analyze the characteristics and implications of the quality management policy through teachers' entire life in Japan case study. This article composed of four chapters; Implication and problem situation, Backgrounds and streams of the japanese teacher reform policy, Characteristics of the main policies about managing the teacher's quality through their life, and Conclusion(Japanese characteristics and the suggestion for Korea). The main quality management policy means the various teacher recruitment and selection system, Merit system of personnel management, Effective management of a system for teachers performing unsatisfactorily, Professional development for teachers with new and 10 years' experience, and Teacher Certificate Renewal System every ten years. The method of study composed of the literature search and interview. The System Analysis[input-process-output-feedback] is used as a model of the analyze the policy process[backgrounds & T.O-quality management system-japanese teacher's reaction & implications to korea] The Central Council for Education(CCE;2012.8.28) has released "An Outline of Measures for Comprehensively Improving the Quality and Ability of Teachers throughout their career". This report can be regarded as a blueprint for the teacher reform policy in japan. As a conclusion, Ten lessons is proposed for the Korea policy improving the quality and ability of teachers(training, employment, and development).

• Cross-Cultural Studies
• /
• v.45
• /
• pp.269-293
• /
• 2016

This research studies the characteristics of the family systems of traditional societies in Black Africa. For this purpose, this study has chosen three subtopics: the distinctive features of traditional societies, marriage customs (polygamy and polyandry), and the societal features of patriarchal and matriarchal societies. First, we analyze men's and women's roles, ownership and management of the land, dowry, and social values of livestock as the distinctive features that support the family system in traditional Black African societies. These elements play an important role in increasing the number of family members. Next we analyze marriage customs-polygamy and polyandry-which increase the number of family members, on the one hand, and secure the labor force, on the other hand. Most traditional societies in Black Africa prectice polygamy. However, the $Bashil{\acute{e}}l{\acute{e}}$ and Bahima prectice polyandry. Polygamy in traditional societies in Black Africa is based on the traditional social customs that display the authority and dignity of the family head, who has control over all family members in both patrilineal and matrilineal societies. The authority and dignity of the family head are used to keep and increase the number of family members, that is, to secure the community firmly. Finally, most traditional societies are patrilineal. However, matrilineal societies are prevalent in the so-called Matrilineal Belt, which term refers to the savanna regions where Bantu peoples reside, that is, the coastal regions from the Angolan coast, bordering the Atlantic, to the Tanzanian and Mozambique coasts that border the Indian Ocean. These societies trace descent through the maternal bloodline. The traditional family system in Black Africa is based on economic social, and political factors, as well as on the community spirit of the members, which has resulted from the choices made to increase the prosperity and well-being of the people.

• The Journal of Korean Philosophical History
• /
• no.39
• /
• pp.53-83
• /
• 2013

This paper aims to examine how issues related to the heaven-human relation (or nature-culture relation) affected Joseon intellectuals in the eighteenth century by considering Huang Yun Seok as a reference. As a significant indicator, the heaven-human relation issue has traditionally been a critical theme in the history of Confucianism. Since Huang Yun Seok accepted Western Learning based on Zhuxi Learning, he is a good example for examining this issue. Huang's ideas didn't depart too much from Confucianism, but he naturally became interested in Western Learning because of the enthusiastic admiration he had of Ancient Learning since he was a child. Principle-Number was consistent with Ancient Learning and Western Learning, and this was somewhat different from the original notion of numerology. It was used for understanding and explaining astronomical phenomenon. In understanding astronomical phenomenon, Huang used both fact-determined and value-centered approaches. Western astronomy allowed him to make an advance in terms of fact-determined approach while the value-centered approach gave him a portentological perspective on astronomical variation such as solar and lunar eclipses. This indicates one of the ways to keep Zhuxi Learning's identity itself amidst an inflow of new learnings.

• Korean Journal of Animal Reproduction
• /
• v.23 no.3
• /
• pp.239-245
• /
• 1999

The effect of catalase on in-vitro maturation in porcine oocytes with or without cumulus cells were studied. The maturation rates were not significantly different in medium with and without catalase during in vitro maturation of oocytes. However, the maturation rates of oocytes with cumulus cells were significantly higher (P＜0.05) than in oocytes without cumulus cells regardless of the presence of catalase. On the other hand, the maturation rate in oocytes cultured with cumulus cells for 48 h (57%) was significantly (P＜0.05) higher than in oocytes with cumulus cells for first 24 h period (42%) only. In another experiment, the maturation rate was significantly (P＜0.05) higher in medium containing catalase for last 24 h period only than in medium containing catalase for first 24 h period during in vitro maturation of ooytes with or without cumulus cells. But the oocytes matured to M-II stage were observed at 24 h of culture of oocytes without cumulus cells only. When oocytes with cumulus cells were cultured for 72 h, the maturation rates was significantly (P＜0.05) higher in medium with (79%) than without (65%) catalase during in vitro maturation. These results indicate that cumulus cells are necessary for in vitro maturation of porcine oocytes, catalase have effect according to the addition periods and can prevent aging of porcine oocytes during maturation in vitro.

• Korean Journal of Animal Reproduction
• /
• v.25 no.4
• /
• pp.305-315
• /
• 2001

In this study, the production of transgenic embryo was attempted by microinjection or round spermatid cultured with foreign DNA. At first, the expression of haploid spermatids specific gene, mTP1 in mouse and hPrm2 in hamster spermatids were investigated by RT-PCR method in testes of young mice and hamster testis. The specific gene expression first appeared at 18 days post partum (dpp) in mice spermatid and 20 dpp in hamster spermatid. Therefore, the round spermatids isolated from 17 dpp mice and 19 dpp hamster were used for the introduction of foreign EGFP gene into haploid round spermatids. For the introduction of EGFP gene haploid round spermatids suspended in medium including EGFP gene were treated with a different electric field strength at 0.11, 0.18 and 0.44 ㎸/cm. After electrical stimulation, viability of testicular sperm cells and 67.6%, 66.4% and 49.9%, in mice and 62.6%, 57.9% and 27% in hamster, respectively. These values were significantly lower than those of non-treated control groups 80.5% in mouse and 69.1% in hamster After 72 hrs culture, the highest expression rate of EGFP gene, 28.5% in mice and 32.1% in hamster were obtained from tile spermatogenic cells electroporated by the field strength or 0.18 ㎸/cm. Then, the ability of fertilization and embryonic development of haploid spermatids transfected with foreign EGFP gene were estimated by the microinjection of spermatids into hamster oocytes. The Irate pronuclear formation rate (77.5%) was lower than non-treated control (80%), and the cleavage rate of the treated group (58.8%) was lower than control (65%). To prove the foreign EGFP integration in hamster embryos, 2-cell stage hamster embryos were subjected to the observation under the fluorescence microscope, and the PCR analysis. As a result, about 44% of 2-cell embryos were showed the integration of EFGP gene into their genome. Therefore, These results suggest the possibility to produce transgenic hamsters by microinjection of haploid spermatid transfected with foreign DNA.

• Journal of Venture Innovation
• /
• v.6 no.3
• /
• pp.185-202
• /
• 2023

The COVID-19 pandemic catalyzed major changes in our work environment, underscoring the critical role of workplace flexibility. While a wealth of research exists on specific flexible work strategies and schedules, a broader understanding of workplace flexibility has been somewhat overlooked. This study aimed to bridge this gap by examining the correlation between workplace flexibility and organizational commitment. Our sample consisted of 300 employees from foreign businesses in the ICT(information and communications technology) service sector and the manufacturing industry, along with those from the top 50 leading Korean enterprises. We bifurcated workplace flexibility into two distinct categories for this study: quantitative and qualitative. Our results revealed that within the quantitative category, the flexibility of continuity of work and flexible place significantly enhanced organizational commitment. Interestingly, the flexibility of work schedules didn't have a marked impact on commitment levels. On the qualitative side, job autonomy and teamwork emerged as significant drivers of organizational commitment. It's worth noting that qualitative aspects of workplace flexibility had a more pronounced effect on organizational commitment than the quantitative elements. These findings highlight the necessity of approaching workplace flexibility from a comprehensive perspective, embracing both its quantitative and qualitative dimensions. For businesses aiming to maximize the benefits of flexibility, it's essential to cultivate a culture of open communication, champion collaboration, and prioritize job autonomy and teamwork. Establishing a work environment that actively supports feedback-oriented communication stands as a key component in this endeavor.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.5
• /
• pp.536-544
• /
• 2001

Three harmful algal bloom species with similar morphology, Cochlodinium polykrikoides, Gyodinium impudicum and Gymodinium catenatum have damaged to aquatic animals or human health by either making massive blooms or intoxication of shellfishes in a food chain. Eco-physiological and hydrodynamic studies on the harmful algae offer useful informations in the understanding their bloom mechanism by giving promising data for the prediction and modelling of harmful algal blooms event. Thus, we studied the abundance of these species in the coastal area of South Sea of Korea and their effects of temperature, salinity, irradiance and nutrient on the growth for the isolates. The timing for initial appearance of the three species around the coastal area of Namhaedo, Narodo and Wando was between Bate July and late August in 1999 when water temperature ranged from $22.8^{\circ}C\;to\;26.5^{\circ}C$ Vegetative cells of C. polykrikoides and G. impudicum were abundant until late September when water temperature had been dropped to less than $23^{\circ}C$. By contrast, vegetative cell of G. catenatum disappeared before early September, showing shorter period of abundance than the other two species in the South Sea. Both G. impudicum and G. catenatum revealed comparatively low density with a maximal cell density of 3,460 cells/L and 440 cells/L, respectively without making any bloom, while C. polykrikoides made massive blooms with a maximal cell density more than $40\times10^6$cells/L, The three species showed a better growth at the relatively higher water temperature ranging from 22 to $28^{\circ}C$ with their maximal growth rate at $25^{\circ}C$ in culture, which almost corresponded with the water temperature during the outbreak of C. polykrikoides in the coastal area of South Sea. Also, they all showed a relatively higher growth at the salinity from 30 to $35\%$. Specially, G. impudicum showed the euryhalic characteristics among the species, On the other hand, growth rate of G. catenatum decreased sharply with the increase of water temperature at the experimental ranges more than $35\%$. The higher of light intensities showed the better growth rates for the three species, Moreover, C. polykrikoides and G. impudirum continued their exponential growth even at 7,500 lux, the highest level of light intensity in the experiment, Therefore, It is assumed that C. polykrikoides has a physiological capability to adapt and utilize higher irradiance resulting in the higher growth rate without any photo inhibition response at the sea surface where there is usually strong irradiance during its blooming season. Although C. poiykikoides and G. impudicum continued their linear growth with the increase of nitrate ($NO_3^-$) and ammonium ($NH_4^-$) concentrations at less than the $40{\mu}M$, they didn't show any significant differences in growth rates with the increase of nitrate and ammonium concentrations at more than $40{\mu}M$, signifying that the nitrogen critical point for the growth of the two species stands between 13.5 and $40{\mu}M$. Also, even though both of the two species continued their linear growth with the increase of phosphate ($PO_4^{2-}$) concentrations at less than the $4.05{\mu}M$, there were no any significant differences in growth rates with the increase of phosphate concentrations at more than $4.05{\mu}M$, signifying that the phosphate critical point for the growth of the two species stands between 1.35 and $4.05{\mu}M$. On the other hand, C. polykrikoides has made blooms at the oligotrophic environment near Narodo and Namhaedo where the concentration of DIN and DIP are less than 1.2 and $0.3{\mu}M$, respectively. We attributed this phenomenon to its own ecological characteristics of diel vertical migration through which C. polykrikoides could uptake enough nutrients from the deep sea water near bottom during the night time irrespective of the lower nutrient pools in the surface water.

• Korean Journal of Veterinary Research
• /
• v.35 no.3
• /
• pp.543-552
• /
• 1995

This study was undertaken to investigate the eftects of Cd administered ad libitum for 6 weeks on the cellular immune responses of Balb/c mice. The results were summarized as follows; 1. The mice fed 25, 50 and 100ppm Cd drank as much as control, but the mice fed 200ppm Cd drank significantly less water after Cd exposure than did control. Increasing rates of body weight of Cd-fed mice for 6 weeks were as this, control group 27.0%, Cd administered groups(25, 50, 100 and 200ppm) 28.54%, 28.31%, 20.49% and 18.04%, respectively. 2. Absolute spleen to body weight(mg/g) of control, 25, 50, 100 and 200ppm Cd administered groups were $4.34{\pm}0.23$, $4.20{\pm}0.54$, $4.80{\pm}0.87$, $4.25{\pm}0.32$ and $4.40{\pm}0.32$, respectively. Splenic cellularity(${\times}10^7$) of control was $24.29{\pm}5.98$ but increased to $27.72{\pm}5.48$, $32.96{\pm}8.44$, $28.32{\pm}8.76$ and $29.64{\pm}4.08$ in 25, 50, 100 and 200ppm Cd-fed groups, respectively. 3. Total $CD_4{^+}$ cells(${\times}10^7$) of control, 25, 50, 100 and 200ppm Cd-fed groups were $9.15{\pm}2.24$, $10.40{\pm}2.04$, $12.04{\pm}3.08$, $10.20{\pm}3.16$ and $10.80{\pm}1.48$, respectively and total $CD_8{^+}$ cells(${\times}10^7$) of these groups were $2.32{\pm}0.56$, $2.54{\pm}0.27$, $3.12{\pm}0.80$, $2.25{\pm}0.70$ and $2.24{\pm}0.28$, in order. On the other hand, $CD_4{^+}/CD_8{^+}$ ratios in total cells were increased significantly except for 50ppm Cd-fed group($3.88{\pm}0.01$). And that of control was $3.97{\pm}0.02$, but those of 25, 100 and 200ppm were $4.35{\pm}0.01$, $4.54{\pm}0.03$ and $4.81{\pm}0.03$. 4. Phagocytosis rates of peritoneal macrophages were increased significantly in 25 and 50ppm Cd groups($36.34{\pm}9.45$ and $37.15{\pm}9.22$, respectively), but 100 and 200ppm groups showed similar rates($18.20{\pm}3.04$ and $19.48{\pm}3.22$ respectively) to that of control($21.43{\pm}3.62$). 5. In mitogen-induced splenocyte proliferation, various concentraions of $CdCl_2(10^{-4}-10^{-7}M)$ were added to mitogen-stimulated culture in vitro. Splenocyte proliferation induced by LPS was decreased dose dependently, but proliferation by Con-A was increased slightly in concentrations of $10^{-7}-10^{-6}M$. 6. Significant cytotoxicity of splenocytes with $CdCl_2$ were shown at $10^{-4}M$ treated group, especially at 24 hrs. From these results, it could be concluded that Cd might modulate the immune responses by modifying a distribution of T cell subpopulations.

• The Journal of Korean Philosophical History
• /
• no.57
• /
• pp.57-90
• /
• 2018

In this discussion, as a way to verify the existence of the system to regulate Zhou dynasty's $z{\bar{o}}ng-mi{\grave{a}}o$(宗廟) numbers, the discussion was focused on '$mi{\grave{a}}o$ (廟)' and '$g{\bar{o}}ng$(宮)' in the records of "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)". As for the parts where the contents of scripture sentences were not specific, the context of the case was investigated through the writings in "$Zu{\breve{o}}-zhu{\grave{a}}n$(左傳)" and other materials. In the cases of the usage of the letter, '$mi{\grave{a}}o$(廟 : a ruler's house, a nation's royal court)', in the scripture sentences in "$Ch{\bar{u}}n-qi{\bar{u}}$(春秋)", the followings need to be noticed. In $t{\grave{a}}i-mi{\grave{a}}o$(太廟) of State $L{\check{u}}$(魯), nationwide events and a ruler's political ancestral rite, $d{\grave{i}}$(?) ritual, were performed, and fancy tools for ancestral rites used in those rituals were equipped. As for the $z{\bar{o}}ng-mi{\grave{a}}o$(宗廟) of a ruler of those times, a ritual of royal court, $ch{\acute{a}}o$(朝) rite, was performed. The usage case of the letter, '$g{\bar{o}}ng$(宮 : house)', is as the following. In $g{\bar{o}}ng$(宮) where a ruler's personal family lived was a family ancestral rite for them carried out. The record about the ornate decorating for the $hu{\acute{a}}n-g{\bar{o}}ng$ house(桓宮), which can be said to have been the political base of $s{\bar{a}}n-hu{\acute{a}}n-sh{\grave{i}}$(三桓氏), three politically noble families of State $L{\check{u}}$(魯), is outstanding. The $x{\bar{i}}-g{\bar{o}}ng$ house(西宮) during $X{\bar{i}}-g{\bar{o}}ng$(魯 僖公)'s reign and a $x{\bar{i}}n-g{\bar{o}}ng$ house(新宮 : a newly built house) destroyed by fire at the third year of $Ch{\acute{e}}ng-g{\bar{o}}ng$(魯 成公), are assumed to have been a ruler's another house, such as the $ch{\check{u}}-g{\bar{o}}ng$ house(楚宮) in which $Xi{\bar{a}}ng-g{\bar{o}}ng$(魯 襄公) used to enjoy staying, which is different from the viewpoint that it might be a $m{\acute{i}}-g{\bar{o}}ng$ shrine(?宮 : a house constructed as a shrine for the deceased father or the deceased grand father) that had been formed since Han dynasty. It has been discussed that, regarding the records that the '$w{\check{u}}-g{\bar{o}}ng$ house(武宮) was built' and that the '$y{\acute{a}}ng-g{\bar{o}}ng$ house(煬宮) was built', certain buildings were established with the symbols of '$w{\check{u}}$(武 : martial arts and force of arms)' and '$y{\acute{a}}ng$(煬 : to burn and get rid of everything)', and the events that a lord stood as its lord continued. Therefore, its main goal was not the performance of a dutiful ancestral rite by a ruler of those times for deceased rulers, for instance, $W{\check{u}}-g{\bar{o}}ng$(魯 武公) or $Y{\acute{a}}ng-g{\bar{o}}ng$(魯 煬公), but display of certain political symbolism through the ritual. This symbolism is most obvious with the $hu{\acute{a}}n-g{\bar{o}}ng$ house(桓宮) and the $x{\bar{i}}-g{\bar{o}}ng$ house(僖宮). As a consequence, all $mi{\grave{a}}os$(廟) and $g{\bar{o}}ngs$(宮) in scripture sentences had the functions of a shrine in some part, but it has been verified that they were not the buildings set up as a shrine to follow '$z{\bar{o}}ng-mi{\grave{a}}o$(宗廟)'s number regulation system' of '$ti{\bar{a}}nz{\check{i}}-7-mi{\grave{a}}o$(天子七廟 : an emperor owns seven $mi{\grave{a}}os$(廟))' or '$zh{\bar{u}}h{\acute{o}}u-5-mi{\grave{a}}o$(諸侯五廟 : a lord owns five $mi{\grave{a}}os$(廟))'.