• Restorative Dentistry and Endodontics
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• v.27 no.6
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• pp.577-586
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• 2002

The purpose of this in vitro study was to compare the effects of root canal cleanness following two Ni-Ti rotary instruments with different rake angle. Thirty-six sound, extracted human premolars with single root were randomly divided into three groups. The used rotary instruments were HEROShaper (Group 1, Micro-Mega, Besancon, France, n=12) and ProFile (Group 2, Maillefer, Ballaigues, Switzerland, n=12). Control group (n=12) was only extirpated with barbed broach (Mani, Matsutani Seisakusho Co., Japan) Group 1 & 2 teeth were prepared to a #40/.04 taper at the apex followed by 1 mm using crown-down technique. After canal preparation and frequent irrigation with 5.25% sodium hypochlorite, the roots split longitudinally into a bucco-lingual direction. Root halves were cross-sectioned in apical third portion again. All root specimens were processed for SEM investigation and photographed. Separate evaluations by one endodontist were undertaken for smear layer on prepared walls with a five score-index for each using reference photograph in root halves. The penetration depth of smear layer into dentinal tubules was also estimated in the other halves. Following results were obtained: 1. Smear layer was observed on all the prepared walls with two experimental groups except control group. 2. Smear layer characteristics in two experimental groups; 1) HEROShaper group showed snowy, dusty appearance and were shown open dentinal tubuli on the prepared walls of almost specimens, and the thickness of smear layer covering onto dentinal surfaces was within 1-2 ${\mu}m$ in a few specimens. 2) ProFile group showed shiny, burnished appearance and complete root canal wall covered by a homogenous smear layer with no open dentinal tubuli in all specimens. The penetration of smear layer into dentinal tubules was found in all specimens and the thickness was at 2-4 ${\mu}m$ in all specimens. These results demonstrated that a completely clean root canal could not be achieved regardless of positive or negative rake angle, which is in accordance with the majority of previous studies on root canal cleanliness In conclusion, through irrigation with antibacterial solutions or chelating agents is recommended to remove the smear layer on prepared canal wall in spite of Ni-Ti instrumentation.

• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.133-139
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• 1994

Eleutherococcus senticocus MAXIM containing compounds for a cordial and lumbago is a native plant in this country. However it is generally difficult to propagate them by seed. This study was carried out to improve propagation efficacy by cutting method using Eleutherococcus senticosus MAXIM collected Mt. Odae for three years$('90{\sim}'92)$. Rooting was delayed by 3 to 12 days but callus formation and rooting percentage was high by 75%, 30% respectively in the treatment of Rooton-F powder, a chemical for rooting promotion, compared with non-treatment. Rooting percentage and rooting characters were not differenced by treatment for remove rooting inhibition compounds and soil-media mixured by 1:1 of vermiculite and perlite was suitable for elevating rooting ratio. A. chiisanensis and A. sieboldianum were rooted well in any time to be cut, while rooting activity of E. senticosus was different by time to be cut. Rooting ratio of E. senticosus was 26%, 36% and 60% when cutten March 20, July 20 and september 20, respectively.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.118-128
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• 2012

As the bearing wall structure, which has been widely applied to domestic apartment buildings since the 1980s, cause many problems during remodeling of buildings, the government encourages constructors to adopt flat plate or rahmen structure through legal incentives. In line with such a trend, the green frame, an eco-friendly rahmen structure that has removed the shortcomings of previous structures, was developed to enhance structural safety, constructability, and eco-friendliness. The construction of green frame can reduce the labor cost and facilitate the composition of iron bars to reduce rebar loss through calculating the quality and establishing the bar bending schedule automatically on the precast concrete member data collected over the design phase. Therefore, the purpose of this study is to develop the algorithm to automate the calculation of iron bar volume for the green frame designed on composite precast concrete members. Automated algorithm to calculate concrete structural design information and design information. Practices through the application site should prove efficacy. The database established by the developed algorithm will automate the establishment of iron bar processing map and bar cutting list and the calculation of optimal composition and order volume to minimize the rebar loss. This will also reduce the expenses on management staff and overall construction cost through the minimization of rebar loss.

• Journal of Digital Convergence
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• v.12 no.11
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• pp.575-583
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• 2014

The purpose of this study was to investigate factors affecting depression among female marriage immigrants in relation to demographic, family, self-efficacy, acculturation, and physical health aspects. The subjects were 556 marriage immigrants residing in Seoul, Keong-gi, and Chung-cheong areas. 47.1% of the subjects showed $${\geq_-}16$$ of CES-D which is the cutting points on depression. The results from hierachical regression analysis indicated that family income(${\beta}=-.13$, p=.002) at the first demographic model and self-efficacy(${\beta}=-.13$, p<.001), family relationship(${\beta}=-.16$, p<.001), acculturation to Korean culture(${\beta}=-.08$, p=.05), acculturative stress(${\beta}=.31$, p<.001), and mal-physical health(${\beta}=.18$, p<.001) at the final model affected female marriage immigrants' depression. The explanatory power of these variables was 37.1%. Based on these results, social services and policies for the prevention of depression among female marriage immigrants were discussed.

• The Korean Journal of Physiology and Pharmacology
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• v.24 no.6
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• pp.441-452
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• 2020

In vivo animal models are limited in their ability to mimic the extremely complex systems of the human body, and there is increasing disquiet about the ethics of animal research. Many authorities in different geographical areas are considering implementing a ban on animal testing, including testing for cosmetics and pharmaceuticals. Therefore, there is a need for research into systems that can replicate the responses of laboratory animals and simulate environments similar to the human body in a laboratory. An in vitro two-dimensional cell culture model is widely used, because such a system is relatively inexpensive, easy to implement, and can gather considerable amounts of reference data. However, these models lack a real physiological extracellular environment. Recent advances in stem cell biology, tissue engineering, and microfabrication techniques have facilitated the development of various 3D cell culture models. These include multicellular spheroids, organoids, and organs-on-chips, each of which has its own advantages and limitations. Organoids are organ-specific cell clusters created by aggregating cells derived from pluripotent, adult, and cancer stem cells. Patient-derived organoids can be used as models of human disease in a culture dish. Biomimetic organ chips are models that replicate the physiological and mechanical functions of human organs. Many organoids and organ-on-a-chips have been developed for drug screening and testing, so competition for patents between countries is also intensifying. We analyzed the scientific and technological trends underlying these cutting-edge models, which are developed for use as non-animal models for testing safety and efficacy at the nonclinical stages of drug development.

• Food Engineering Progress
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• v.14 no.4
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• pp.316-321
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• 2010

The efficacy of the ozonated water (0.1, 0.2, 0.4, 0.6, and 1.0 ppm) in reducing the risk of food-borne disease was investigated in this study. After inoculation of Listeria monocytogenes (ATCC 19112), Salmonella enterica subsp. enterica biovar Typhimurium (ATCC 12598), Escherichia coli O157:H7 (ATCC 43890) to lettuce, spinach, and beef, inhibition effect with different washing concentrations, time, and methods with ozonated and tap water were evaluated. As a result, there were 2.16 to 3.85 log CFU/mL reduction in different foods and 7 log CFU/mL reduction on cutting boards after watering with ozonated water. Higher than 0.2 ppm of ozonated water treatment reduced the growth of food-borne disease bacteria with increasing washing time and ozone concentration. These results suggested that the ozonated water treatment effectively improved the microbiological quality and food safety.

• Journal of Dental Anesthesia and Pain Medicine
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• v.24 no.4
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• pp.245-264
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• 2024

Computer-controlled local anesthesia delivery (CCLAD) is an innovative electronic injection device that represents a cutting-edge approach to dental anesthesia. This system is promising for painless anesthesia using controlled anesthetic injections. This review aimed to compare the discomfort experienced by patients during local anesthesia using a traditional syringe and the CCLAD system and evaluate the potential of the CCLAD system as a painless dental anesthesia solution. The inclusion criteria for this study were based on the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The study population, including children and adults, underwent dental anesthesia using the CCLAD system, ensuring a comprehensive and representative sample that instills confidence in the validity of the results. Fourteen clinical trials were included in the analysis after they fulfilled the eligibility criteria. We found that using computer-assisted anesthetic equipment not only led to a significantly lower pain perception score, but also had a profound positive impact on patient behavior. Patients using the CCLAD device exhibited more cooperative and helpful conduct, indicating the system's effectiveness in improving patient comfort and experience and reassuring the audience about its positive impact. In conclusion, using a computer-assisted anesthetic device such as the CCLAD system significantly reduced pain perception scores and improved patient behavior, making them more cooperative and helpful. These findings offer hope for pediatric dentistry and apprehensive adult patients, suggesting a more comfortable and less daunting dental experience with the CCLAD system.

• The Journal of Internal Korean Medicine
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• v.32 no.1
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• pp.87-99
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• 2011

In the 18th century, Xu Lingtai (徐靈胎) and Yoshimasu Todo (吉益東洞) were medical revolutionaries. They emphasized researches about synthesis of formulae, efficacy of medication and observation and then classification of clinical phenomena, so they assumed a modern scientific character. But, there were clear differences between their academic thoughts. In this paper, we examine the causes of difference in three fields, i.e. traditional culture, viewpoints of talented people and academic personality. The first, difference was due to traditional culture. Chinese medicine has a long history and heavy traditional culture. Yin-Yang (陰陽) theory, Five Phase(五行) theory, Viscera and Bowels (臟腑) theory and Meridian and Collateral (經絡) theory stemmed from everyday practice, and Chinese people learn these theories from experience and observation. From the standpoint of Chinese people, particularly scholarly doctors [儒醫] such as Xu Lingtai, it was easy to debate medical theories. In contrast, Japanese traditional culture didn't have as long a history as China. Thus as a necessity, it was harder to disseminate traditional Chinese medicine theories in Japan. Yoshimasu Todo simplified it by cutting out the superfluous traditional Chinese medicine theory, so at that time it must have been shocking to the Japanese medical world's trends. The second, difference was due to viewpoints of talented experts. From the standpoint of Xu Lingtai, above all, medicine is just a learning, only a kind of technique, even more not a means of living. Xu Lingtai was concerned with the appearance of very talented experts such as 'great man' (偉人), and 'exceptional man' (奇士) who carried out medical research. Instead of cultivating a few talented people, Yoshimasu Todo tried to produce a large number of clinicians quickly who could treat ordinary people. The third was due to personality difference. As Xu Lingtai threw away Confucianism and studied medicine in his youth, although he had a critical attitude, he was always mild-mannered. Yoshimasu Todo always had a clearly critical and rebellious nature. Personality influenced their literary spirit and learning style, so although both advocated reactionism, the academic thought of Xu Lingtai was reformative and mild, while that of Yoshimasu Todo was revolutionary and fierce. Xu Lingtai and Yoshimasu Todo had considerably similar research domains and academic thought, so it is proper for them both to serve as examples for making a comparative study of medical history in China and Japan in 18th century.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.1
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• pp.181-197
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• 2013

Objectives : This study aimed to assess the differences in treatment behavior by reviewing data of a medical institution that studies treatment behavior in URI and assessing the treatment efficacy in Korea. Methods : We analyzed the behavior of medical customers and providers of upper respiratory infection medications using the NPS published by the Health Insurance Review Assessment Service. We created an operational definition for complications, and confirmed the difference in complication distribution between medical specialties. We also performed a multivariate analysis using a mixed model to elucidate the factors influencing the occurrence of complications. Results : The outcomes of analyzing factors to influence the difference in practice patterns of the diagnosing URI between the physicians are as follows; (1) Analysis of antibiotics prescriptions rate showed significant difference from medical departments (pediatrics; 49.7%, internal medicine; 54.2%, otorhinolaryngology; 69.6%, family medicine; 61.6%, general surgery; 57.5%, p<0.001). Analysis of steroid prescriptions rate showed significant difference from medical departments (pediatrics; 3.8%, internal medicine; 4.5%, otorhinolaryngology; 5.4%, family medicine; 3.0%, general surgery; 11.2%, p<0.001). (2) In patients who visited medical institutes with the common cold, the complication distribution differed according to the medical specialty, which suggests that specific complications arise depending on the particular medical specialty (p<0.001). (3) Moreover, through multivariate analysis, we found that the complication rate is higher in clinics than in hospitals, depending on the institute's size. (p<0.001; odds ratio of 4.67 in clinics than in hospitals, 95% CI 2.66-8.21) Conclusions : We observe a deviation between the behavior of patients diagnosed with URI and medication providers. This may arise from the interaction between providers and consumers, wherein the complications are associated with the choice of outpatient department and the prevention of cutting incentives. These findings suggest that the health policies should be improved to prevent inappropriate medical practice in the treatment of pediatric URI.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.5
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• pp.445-451
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• 2019

In the industrial production of fish snacks using frozen surimi, molding the surimi mixture requires an expensive automated machine. This study investigated the efficacy of freeze molding without machinery molding in the production of Alaska pollock Theragra chalcogramma surimi snacks. At 90 minutes after deep freezing at $-80^{\circ}C$, the cutting ease and shape retention of the surimi mixture were superior. The freezing-molded surimi snack had a higher TVB-N (total volatile basic nitrogen) level (3.59 mg/100 g) than that (1.50 mg/100 g) of the normally molded surimi snack. Freezing did not affect the microstructure of the surimi snack or its hardness, which is an important physical property of snack products. The freezing-molded and normally molded snacks did not differ significantly in terms of color or appearance, or in any other aspect of the sensory evaluation. Our findings demonstrate that freeze molding does not induce changes in the quality of surimi snacks. Therefore, molding by freezing treatment could be used to produce surimi snacks at small- and mid-sized seafood companies.