• Restorative Dentistry and Endodontics
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• v.29 no.5
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• pp.446-453
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• 2004

The aim of this study was to evaluate the shaping abilities of four different rotary nickel-titanium instruments with anticurvature motion to prepare root canal at danger zone by measuring the change of dentin thickness in order to have techniques of safe preparation of canals with nickel-titanium files. Mesiobuccal and mesiolingual canals of forty mesial roots of extracted human lower molars were instrumented using the crown-down technique with ProFile, $GT^{TM}$ Rotary file, Quantec file and $ProTaper^{TM}$. In each root, one canal was prepared with a straight up-and-down motion and the other canal was with an anticurvature motion. Canals were instrumented until apical foramens were up to size of 30 by one operator. The muffle system was used to evaluate the root canal preparation. After superimposing the pre- and post-instrumentation canal. change in root dentin thickness was measured at the inner and outer sides of the canal at 1. 3, and 5 mm levels from the furcation. Data were analyzed using two-way ANOVA. Root dentin thickness at danger zone was significantly thinner than that at safe zone at all levels (p < 0.05). There was no significant difference in the change of root dentin thickness between the straight up-and-down and the anticurvature motions at both danger and safe zones in all groups (p > 0.05). ProTaper removed significantly more dentin than other files especially at furcal 3 mm level of danger and safe zones (p < 0.05) Therefore, it was concluded that anticurvature motion with nickel-titanium rotary instruments does not seem to be effective in danger zone of lower molars.

• Hwankyungkyoyuk
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• v.21 no.4
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• pp.40-66
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• 2008

The purpose of this study is to develop and applicate textbook relevant to school indoor air quality. To achieve the purpose, concrete study process are as follows. First, the survey research to teachers, supervisors, and students is conducted to grasp cognition of subjects in elementary school and management situation about school indoor air quality. Second, contents relevant to indoor air quality on textbooks in the 7th elementary curriculum and subsidiary textbooks is analysed through reference study. Third, environmental textbook relevant to school indoor air quality for 5th and 6th grade in elementary school is developed, applicated, and inspected its effect on the basis of implications from results of survey and reference study. The results of this study are as follows. First, the result of survey concerning school indoor air quality showed that three groups had negative attitude for its management even though they thought that it affected human's health and study by and large. Student group thought that each of students itself was a little influence to school indoor air pollution though all of three groups answered that' activities of students' was its main source. Efforts of students to improve school indoor air quality was not much, and its main reason was that they didn't know about school indoor air pollution well. Second, result of analysis into textbooks on the 7th elementary curriculum and subsidiary textbooks, contents concerning indoor air on the 7th elementary curriculum textbooks was little or nothing. And it trended to be included to subsidiary textbooks. However, education textbooks about indoor air for elementary students was insufficient still. Third, environmental textbook relevant to school indoor air quality for 5th and 6th grade in elementary school was developed. It was constructed for themes - importance, sources, effects, and management of school indoor air quality. After its application to the 6th grade students in elementary school, it was meaningful in the level of p<.05 that the result of knowledge and awareness in the pre-post test within experiment group. However, all of the results in comparison group didn't represent statistically meaningful difference. In conclusion, environmental textbook developed by necessity of education about school indoor air quality will play a role as useful tool for the 5th, 6th grade students in elementary school to understand relation of quality of health and life and school indoor air quality, to have attitude to make an effort to manage it by develop right awareness about it.

• Archives of design research
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• v.19 no.1 s.63
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• pp.151-162
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• 2006

Nowadays most business organizations wish to hire competent people who can do their own jobs efficiently right after their employment. The primary goal of this study is to focus on how we can train undergraduate students in academia-industry collaboration to satisfy this requirement. By making use of the funding from the Ministry of Education & Human Resources Development to support academia-industry collaboration program, we established an intramural company, Hankyong Design Company, and set up several studio courses for junior and senior students. To develop these courses efficiently for the first semester of 2005, studied both intramural and extramural environments of academia-industry collaboration and searched for good examples of them. Based on this investigation, I made some assumptions that how we can perform the academia-industry collaboration program for undergraduate students successfully. I chose several design tasks related to digital communications, and appointed WisePost Inc., an Internet communication service company for MSN Messenger, to be a collaborator. We made the 'Interactive Design' studio courses together and applied the courses to 20 juniors. At the end of the semester, we evaluated the works of the students, and selected and commercialized some excellent items among them. During the course work, I realized the fact that education programs in academia-industry collaboration is feasible for undergraduate students majoring in design. I understanded the overall merits and demerits of conventional studio and academia-industry collaboration courses. In addition, the results from the present study suggest that the role of professor in academia-industry collaboration program would be quite different from conventional studio courses.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.33 no.3
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• pp.199-209
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• 2011

Purpose: Osteoporosis, is a major health problem for the elderly and post-menopausal women and shown to alter the properties of bone as well as impair bone healing around titanium implants in both human and animals. The objective of this study was to examine the effect of LIPUS with adipose-derived stem cells on the healing process around a titanium implant in rats with osteoporosis. Methods: Sixteen osteoporosis-induced rats were divided into two groups: an adipose-derived stem cell injected with Low Intensity Pulsed Ultrasound (LIPUS) application group and a control group. Titanium screw implants (diameter, 2.0 mm: length, 3.5 mm, Cowell Medi, Korea) were placed into both tibia of 16 rats, on 8 rats as the control group and the other 8 rats as the experimental group. Rats were sacrificed at different intervals from 1, 2, 4 and 8 weeks after implantation for histopathologic and immunohistochemical analyses. Results: Histopathological analysis revealed newly formed bone in experimental group earlier than that in control group. Especially at 1 week after implantation, more amounts of new bone matrix and collagen around the implant in the experimental group were seen compared with the control group. Immunohistochemical analysis showed that the levels of osteoprotegerin (OPG) expression in the experimental group were increased at early stages compared with that of control group until 2 weeks after implantation. But after 2 weeks, the expression level of OPG similar in both groups. The expression levels of receptor activator of nuclear factor kB ligand (RANKL) were stronger in the experimental group than the control group until 2 weeks after implantation. After 4 weeks, expression of RANKL in experimental group was similar to the control group. Conclusion: The results of this study suggest that LIPUS with Adipose-Derived Stem Cells in implantation could promote bone healing around titanium implants in rats with osteoporosis.

• Journal of the Korea Institute of Building Construction
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• v.17 no.4
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• pp.349-360
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• 2017

In concrete construction work, formwork is an important process that accounts for 10% of the total construction cost. Recent buildings are becoming bigger and higher. In order to maximize the efficiency and safety of this formwork, the system of formworking has been systematized. However, the human accidents and the noise complaints arise from dismantling processes frequently occur. In order to solve these problems, most of them are dependent on foreign technology, but they do not take into consideration the conditions of domestic construction site. In this study, we developed a table type multi-drop system form for a slab and beam which can improve the process, safety and reduction of disassembly noise, and evaluated the physical properties of the main members which are used in the system. The results of this study show that there is sufficient strength to be used as a slab and a laying material for both a yoke beam and a supporting post. The noise level is improved compared to existing method.

• Journal of the Korean Society of Costume
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• v.54 no.3
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• pp.27-42
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• 2004

Music videos provide for many others images, alluring the audience to fall in another emotional world, while the sexual images shown in them suggest new images of man and woman. Today, men's images are being interpreted from various viewpoints. As interests in men's fashion are visualized through music video clothing, not only juveniles who want to be identified with the music video images but also adults try to imitate them, and proceed to wear the clothing, obliterating the boundary between 'reality' and 'illusion' and creating new images of men. This study is aimed at reviewing the male images shown in the music videos, particular their clothing, produced between 2000 and 2002. The results of this study could be summarized as follows : 1. Since beginning of the human history, men's image has been characterized by patriarchal system, capitalism, bourgeois class which emerged after industrial revolution and other man-dominant socio-cultural phenomena, such male image are shown in the music video as conservative and dominant image. 2. However, due to the post-modern culture, the power began to be decentralized. while feminism and men's liberation movement gain strength. As a result, women or heterosexuals began to regard men as sexual objects, and such a phenomenon is featured as sexual, bisexual or decadent images in the music videos. 3. On the threshold of the 21st century, music videos have begun to creatively describe men's life, their social conflicts, dreams and hopes and death and thereby. feature men's such images as being destroyed in view of existentialism. The numerous creative men's images interpreted in this way are featured in many music video works only to create playful, cyborg or demonic images using the senses. After all, men's images are featured in the music video costumes in diverse ways ranging from the conventional images to acquiescent images. In addition, various male images are combined with the characteristics of the music videos to be re-created anew. The young men in the our modern age tend to imitate or apply such images to create their own images or individualistic styles. All in all, men's image can be fixed no longer but diversified and fragmented in the new age.

• Development and Reproduction
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• v.4 no.1
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• pp.101-108
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• 2000

Objectives: The pleiotrophin (PTN) and midkine (MK) are secreted heparin-binding neurokines that share 50％ sequence homology. PTN and MK are expressed in the range of primary human tumors. The association of PTN and MK with carcinogenesis, enhancement of plasminogen activator activity and angiogenic factor are reported. Patients with endometriosis are characterized by the ability of the endometrium to implant; angiogenic and growth factors may play a significant role in the pathogenesis of endometriosis. To test the hypothesis that higher expression of PTN and MK in endometrium from women with endometriosis might be increase angiogenesis and growth ectopic endometriosis implants, we investigated PTN and MK expression by quantitative and competitive polymerase chain reaction (QC-PCR) in endometrium from women with and without endometriosis throughout the menstrual cycle. Design: MK and PTN mRNA expression in endomeoium from women with endometriosis and control patients without endometriosis were determined by QC-PCR throughout the menstrual cycle. Methods: Endometrial tissue was obtained from 25 patients with severe endometriosis and 30 patients without endometriosis undergoing hysterectomy or endometrial biopsy. Stage of endometrial cycle and a diagnosis of endometriosis were confirmed histologically. Total RNA was extracted and reverse transcribed into c-DNA. QC-PCR was performed to evaluate PTN and MK mRNA expression. Results were analysed by Post Hoc test. Results: MK and PTN were expressed throughout the menstrual cycle in both groups. MK expression was higher in follicular phase than luteal phase in endometrium from normal women. endometrium from endometriosis patients showed increased expression of PTN and MK compared to endometrium from normal women in the luteal phase (p<0.05). Conclusion: Our results suggest that uterine endometrium from women with endometriosis expresses higher levels of MK and PTN than endometrium from normal women during luteal phase. Increased MK and PTN expression may be related to the initiation of ectopic endometrial implants and their subsequent peritoneal invasion.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.77-88
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• 2010

In order to ensure good animal health and performance, it is essential to produce forages with high feeding value and good hygienic quality. However, huge amounts of forages consumed by ruminants are contaminated with mold prior to harvest or during storage as hay, straw or silage. These mold can grow in forages only when nutrients are available, correct temperature exist, oxygen is present, and unbound water is available. Fungal 'species can be divided into two groups: field fungi and storage fungi. Field fungi invade the forages while the crop is still in the field, require high moisture conditions, and are such as species of Fusarium, Alternaria, Clodosporium, Diplodia, Gibberrella and Helminthosporium. Storage fungi invade forages during storage and need less moisture than field fungi. These such as species of Aspergillus and Penicillium usually do not occur any problem before harvest. Mold growth can spoil the nutritional aspects of the forages and also results in secondary metabolites that are highly toxic to animal, humans and plants. Moldy feeds are less palatable and may reduce dry matter intake. This, in turn, leads to a reduction of nutrition intake, reducing weight gains or milk production. Performance losses of 5 to 10 percent are typical with moldy feeds. Mycotoxins are toxic substances produced by fungi (molds) growing on crops in the field or storages. While greater than 400 mycotoxins have been chemically identified, the biological or veterinary medical impact of only several mycotoxins is known. Mycotoxins have attracted considerable attention as potential causes for poor performance and health disorders in domestic livestock. They can be carcinogenic, hepatotoxic, hematotoxic, immunosuppressive, estrogenic, or mutagenic. So, feeding moldy forages has adverse effects on animal health and milk consumers. Also, this author reported that rice straw hay was contaminated mycotoxigenic fungi such as Penicillium roqueforti and Fusarium culmorum in Korea. Therefore, it is an urgent need to develop an improved post harvest storage method to reduce nutrient loss and mycotoxin contamination of forages, which will have a positive impact on human health.

• Parasites, Hosts and Diseases
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• v.55 no.6
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• pp.613-622
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• 2017

IL-12 and IL-23 are closely related in structure, and have been shown to play crucial roles in regulation of immune responses. However, little is known about the regulation of these cytokines in T cells. Here, we investigated the roles of PI3K and MAPK pathways in IL-12 and IL-23 production in human Jurkat T cells in response to Toxoplasma gondii and LPS. IL-12 and IL-23 production was significantly increased in T cells after stimulation with T. gondii or LPS. T. gondii and LPS increased the phosphorylation of AKT, ERK1/2, p38 MAPK, and JNK1/2 in T cells from 10 min post-stimulation, and peaked at 30-60 min. Inhibition of the PI3K pathway reduced IL-12 and IL-23 production in T. gondii-infected cells, but increased in LPS-stimulated cells. IL-12 and IL-23 production was significantly reduced by ERK1/2 and p38 MAPK inhibitors in T. gondii- and LPS-stimulated cells, but not in cells treated with a JNK1/2 inhibitor. Collectively, IL-12 and IL-23 production was positively regulated by PI3K and JNK1/2 in T. gondii-infected Jurkat cells, but negatively regulated in LPS-stimulated cells. And ERK1/2 and p38 MAPK positively regulated IL-12 and IL-23 production in Jurkat T cells. These data indicate that T. gondii and LPS induced IL-12 and IL-23 production in Jurkat T cells through the regulation of the PI3K and MAPK pathways; however, the mechanism underlying the stimulation of IL-12 and IL-23 production by T. gondii in Jurkat T cells is different from that of LPS.

• Journal of the Korean Arthroscopy Society
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• v.6 no.2
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• pp.121-125
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• 2002

Purpose : The purpose of this study was to assess the clinical outcomes and radiological changes of arthroscopic augmentation with synthetic polyester ligament for posterior cruciate ligament injury Materials and Methods : The assessment was made among 60 patients who underwent arthroscopic augmentation with synthetic polyester ligament (ABC ligament, Surgicraft, U.K.) into the substance of ruptured PCL proper under the arthroscopic control from January, 1990 to January, 1996 and whose follow-up period was more than 5 years (average 7.8 years). The results were analyzed by using the posterior stress radiographs by Telos stress device, KT-2000 arthrometer and the clinical assessment by using Lysholm knee score. Results : The average difference of posterior displacement on stress radiographs were 13.2 mm preperatively and 3.6 mm at last follow up. Both knee showed minimal difference on KT-2000 arthrometer (0.7 mm on 20 lb) at the last follow-up. The mean Lysholm knee score was 49.2 preoperatively and improved to 84.3 post-operatively. Conclusion : Authors observed that long-term results of arthroscopic augmentation with synthetic polyester ligament for PCL injury were similar with those using human allograft. Taking these results into consideration, the synthetic polyester ligament is assumed to be a method of treatment of the PCL injury.