• Journal of Radiation Protection and Research
• /
• v.38 no.2
• /
• pp.78-90
• /
• 2013

Recently, the interest on exposure to radiation is rising. The radiation exposure of mammography is higher in absorbed dose than of X-ray, therefore unnecessary exposure needs to be reduced, and higher image quality is needed. Generally, ray quality of the radiation imaging is an important factor that determines image quality and the amount of ray exposure, and they are affected by tube voltage and added filter. The X-ray energy that is exposed from mammography device is generally a continuous spectrum, which includes low energy that has minute influence on the image quality, and high energy that hinders contrast on image. Currently, molybdenum (Mo) and rhodium (Rh) are the most used added filters for mammography device, and they are used differently according to the energy region of X-ray. This study aims to find out the degree of reduction in exposure dose according to the thickness of aluminum (Al), and to study the changes in image quality and dose when the added filter plates that are made with niobium (Nb) or zirconium (Zr) are used, other than molybdenum (Mo) and rhodium (Rh), the two most used added filters that have similar atomic number and K-absorption regions as Nb and Zr. In this study, single-added filters of molybdenum (Mo), niobium (Nb), and zirconium (Zr) are used, and in some cases, Aluminum (Al) is combined with the single filters. In this case, image quality is considered to be improved depending on the type of added filters, and by using Aluminum (Al) filter together with the others, unnecessary X-ray of low energy would be absorbed, therefore the dose is expected to decrease without any influence when the concentration level becomes identical.

• Journal of The Korean Association For Science Education
• /
• v.38 no.4
• /
• pp.467-480
• /
• 2018

This study aims to investigate how flipped learning-based socioscientific issue instruction (FL-SSI instruction) affected middle school students' key competencies and character development. Traditional classrooms are constrained in terms of time and resources for exploring the issues and making decision on SSI. To address these concerns, we designed and implemented an SSI instruction adopting flipped learning. Seventy-three 8th graders participated in an SSI program on four topics for over 12 class periods. Two questionnaires were used as a main data source to measure students' key competencies and character development before and after the SSI instruction. In addition, student responses and shared experience from focus group interviews after the instruction were collected and analyzed. The results indicate that the students significantly improved their key competencies and experienced character development after the SSI instruction. The students presented statistically significant improvement in the key competencies (i.e., collaboration, information and technology, critical thinking and problem-solving, and communication skills) and in two out of three factors in character and values as global citizens (social and moral compassion, and socio-scientific accountability). Interview data supports the quantitative results indicating that SSI instruction with a flipped learning strategy provided students in-depth and rich learning opportunities. The students responded that watching web-based videos prior to class enabled them to deeply understand the issue and actively engage in discussion and debate once class began. Furthermore, the resulting gains in available class time deriving from a flipped learning approach allowed the students to examine the issue from diverse perspectives.

• Tuberculosis and Respiratory Diseases
• /
• v.58 no.5
• /
• pp.480-489
• /
• 2005

Background : Dysregulation of apoptosis plays an important role in carcinogenesis, tumor progression, and resistance to chemotherapy. X-linked inhibitor of apoptosis (XIAP) is considered to be the most potent caspase inhibitor of all known IAP (inhibitor of apoptosis) family members. This study was designed to assess the pattern of expression and the prognostic value of XIAP in radically resected non-small cell lung carcinoma (NSCLC) patients. Method : The expression of XIAP and its relationship with clinicopathologic parameters (patient age, TNM stage, TNM-pT, TNM-pN, histologic type, VEGF expression, microvessel density, PCNA index) and overall survival were analysed with formalin-fixed, paraffin-embedded blocks from eighty cases of NSCLC. In addition, the apoptotic index (AI) was also assessed. Results : In a regard to histologic type, squamous cell carcinoma (SCC) showed XIAP expression in 91.3%(42/46) and adenocarcinoma (AC) in 61.8%(21/34). The difference was significant(p=0.001). There was no correlation between XIAP expression and other parameters. In the group of AC, XIAP expression showed the signifcant correlation with older age group ${\geq}58years$ and VEGF expression(p=0.028, p=0.014, respectively). The AI in the group with or without XIAP expression were $2.5{\pm}4.9%$ and $18.5{\pm}28.9%$, respectively(p=0.001). Both groups just aforementioned showed no significant difference in median survival time (42.5 months, 29.8 months, respectively). Conclusion : This study suggests that the XIAP expression in NSCLCs could have relation to inhibition of apoptosis, and show differential expression according to histologic type. However, its prognostic role during the progression of NSCLC needs to be further defined.

• The Korean Society of Law and Medicine
• /
• v.18 no.2
• /
• pp.163-194
• /
• 2017

Coronary artery disease has increased in Korea as the country enters the aged society. It is well known that the incidence of coronary artery disease is related to aging, hypertension, diabetes, hyperlipidemia, and dietary habit. For effective treatment of significant coronary stenosis, close coordination between cardiac surgery and cardiology team is essential. Especially cardiologists' decision whether to do the stent placement or CABG is very important because the cardiologists usually start to consult the patients for their treatment. Recently, non-surgical interventions(that is stent placement) in cardiology field have dramatically increased as the national insurance system removed the limitation of the number of stents deployed. However, accidents are often caused by inappropriate use of stents, especially in patients with triple coronary disease or left main disease with heavy coronary calcifications. Another aspect of stent placement is to cope with an emergency case in the event of coronary rupture or pericardial tamponade during coronary interventions without cardiac surgeons. In the past two years, the Korea Consumer Agency (Consumer Dispute Coordination Committee) analyzed eight cases of medical dispute settlement. Only two hospitals were manned with both cardiologists and cardiac surgeons. Seven patients died of procedures of stenting and five patients died on the day of the procedure. Among the 8 cases, 5 cases showed 3 vessel disease and the rest of the cases had either severe calcification, complete occlusion or poor coronary antomies for stenting According to a 2017 national data registry of coronary stenting, less than 3 drug-eluting stents were implanted in 98% of all patients. In 2015, the number of stent procedures was 38,922, and approximately in 800 (2%) cases, more than four stents were used per patient. We emphasize that it is necessary to seriously consider the cost-benefit analysis between stent and CABG. The patient has the right to choose the right procedure by asking the liability of 'instruction explanation obligation'. He should be well informed of the pros and cons of both procedures to avoid overuse of stent. It can be solved by intimate discussion of individual cases with the cardiac surgeon and the patient. Unilateral dialogue with the patient, forceful restriction on the number of stenting, lack of surgeon's backup in difficult cases should all be avoided. It is also necessary to solve the problem not only at the hospital level, such as multidisciplinary integrated medical care, but also a nationwide solution such as expanding cardiac surgeons as essential personnel to public officials.

• Journal of dental hygiene science
• /
• v.11 no.5
• /
• pp.389-395
• /
• 2011

The purpose of this study was to examine dental hygiene students' achievement motivation and factors affecting dental hygiene students' achievement motivation by the general characteristics of subjects in this study. The subjects in this study were 450 who were selected by convenience sampling from three different three-year-course colleges. After a survey was conducted, the answer sheets from 421 respondents were analyzed. The collected data were analyzed, which made use of t-test, ANOVA and Kruscal-Wallis test. The findings of the study were as follows. 1. The dental hygiene students investigated got 3.34 in achievement motivation. They got the highest score of 3.78 in the item 'I perform what I have to do with a sense of responsibility.' and they got the lowest score of 2.67 in the item 'I like to do something risky.' 2. Concerning links between their general characteristics and achievement motivation, the students whose academic year was higher(p<0.001) and who had more clinical practice experiences (p<0.01) were better motivated than their counterparts. As to connections between achievement motivation and expected post-graduation length of service, those who replied that they planned to find another job after getting married were better motivated(p<0.05). Regarding relationship between achievement motivation and a will to work abroad, the students who had a stronger will to work abroad were better motivated. 3. As a result of checking the influence of their general characteristics on achievement motivation, stronger motivation was found among the students whose academic year was higher(p<0.01), who intended to work until marriage(p<0.01) and who didn't plan to keep working after marriage(p<0.05) when the other variables were controlled. Therefore dental hygiene students should be taught to look at things positively when they enter college, and they should also be educated to become progressive to keep working for their lifetime instead of just getting a temporary job after graduation.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.30 no.1
• /
• pp.93-102
• /
• 2004

Recently, the golden age of herbal cosmetics has come. Along with active introduction of oriental herbal lines, diversification of distribution channels is designated as a major feature. In this background, the present study attempts to consider the domestic market for oriental herbal cosmetics, which is growing rapidly with the introduction of various new brands, and examine the perceptions of this new type of cosmetics by women consumers based on their purchase behaviors, and search for the ways for its promotion and development. A survey was conducted to adult women consumers aged 19∼60 residing in Seoul or Gyeonggi-do. Out of a total of 430 surveys distributed, 350 answer sheets were used for the analysis Among the results, the first-hand information on the herbal cosmetics market, their usage, and the consumer needs obtained in the present study will serve as a fundamental data for planning the marketing strategies for the oriental herbal cosmetics.

• The Journal of the Petrological Society of Korea
• /
• v.22 no.3
• /
• pp.219-233
• /
• 2013

Spherulitic rhyolite occur as part of ring dyke which showing a vertical flowage of $60^{\circ}{\sim}90^{\circ}$, of the Jangsan cauldron was studied. The spherulites range in diameter from a few millimeters to 2.8 centimeters or more, and average 5~10 millimeters. It belongs to radiated simple spherulite type. They consist of a core of moderate brown dense material encased by a thin crust, a few millimeters thick at most of white grey material. The spherulites frequently have a radiating fibrous structure, which are thought to have formed as a consequence of rapid mineral growth caused by very fast cooling of the dykes in shallow depth near the surface. EPMA examination of the concentric-zoned core of spherulites show that they are mainly composed of cryptocrystalline-fibrous intergrowth of silica minerals and alkali feldspars which have $SiO_2$ 82% or more, $Al_2O_3$ 7~10%, $Na_2O+K_2O$ less than 8%. The feldspar compositions of the spherulites lie essentially within the sanidine field. XRD examination show that spherulites are mainly composed of quartz, sanidine, albite with minor mica, kaolinite and chlorite. According to X-ray mapping, the spherulites are enriched in $SiO_2$ in the core and partly enriched $Na_2O$ or $K_2O$, $Al_2O_3$ in the shell that reflect in compositional zoning with increasing spherulitic devitrification. The feathery and non-equant crystal shapes of spherulites from rhyolite dyke of Jangsan cauldron suggest that they may have formed during the rapid cooling of dyke under the static state, or faster velocity of devitrification from glassy materials than movement velocity of the magma intrusion. The spherulitic rhyolite originated from high-silica(75.4~75.7 wt.%) rhyolite magma.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.13 no.1
• /
• pp.104-111
• /
• 2009

Purpose: Osteocalcin is also known as the bone gamma-carboxyglutamic acid (Gla) protein (BGP), is noncollagenous bone protein synthesized by osteoblasts. Serum concentrations of Osteocalcin have been used as a biochemical marker of bone turnover. The reference intervals of Osteocalcin is categorized by kit corporation according to the age. However, each laboratory should establish its own reference intervals. In this study, the variation in the serum Osteocalcin level were used to find actual standard age-specific Osteocalcin reference intervals. Materials and Methods: We have selected 864 healthy females aged 20~80 years who visited a health promotion center between Aug. 2007 and Sep. 2008. The Osteocalcin IRMA Kit (OSTEO-RIACT, CIS Bio international, Gif-sur-Yvette, France) was used for the quantification. Each results were analyzed with the SPSS 12.0 statistical software. Results: The analyzed reference intervals of Osteocalcin by using Hoffmann method are from 8.8~39.4 ng/mL to 6.3~28.8 ng/mL for the case of the age from 20 to 30, from 7.7~31.9 ng/mL to 5.9~17.4 ng/mL for the case of the age from 31 to 40, and from 8.0~36.0 ng/mL to 5.5~20.1 ng/mL for the case of the age from 41 to 50, and from 8.0~50.5 ng/mL to 6.7~27.0 ng/mL for the case of the age from 51 to 60, and from 12.9~55.9 ng/mL to 7.5~27.5 ng/mL for the case of the age from 61 to 80. Reference intervals of Osteocalcin were not in agreement with those recommended by the manufacturers. Conclusions: Osteocalcin is used as an indication of metabolic bone diseases. So in our study we wanted to provide reference intervals of Osteocalcin that can be useful to a clinical decisions. Also, previous reference intervals should not be re-used and new intervals should be set by continuous analyzing.

• Tuberculosis and Respiratory Diseases
• /
• v.52 no.5
• /
• pp.463-474
• /
• 2002

Background : This study was designed to examine how glutathione, one of the nucleophilic sulfur compounds, effects the cisplatin cellular toxicity in the non-small cell lung cancer cell lines and normal lung epithelial cell line. Materials and Methods : Three cultured cell lines, the lung adenocarcinoma cell(NCL-H23), the lung squamous carcinoma cell(SK-MES-1) and the normal lung epithelial cell(L-132) line were exposed to various concentrations of cisplatin with or without glutathione. The relative viability was estimated as a means of measuring the cisplatin cellular toxicity using the MTT method. Results : In NCI-23, the response to cisplatin was sensitive but glutathione markedly increased the relative survival of the tumor cells by removing the antitumor effect of cisplatin. In both SK-MES-1 and L-132, the responses to cisplatin were less sensitive, and the chemoprotective effect of glutathione compared to and equal cisplatin dose was significantly higher in L-132 than in SK-MES-1(p<0.05). Conclusion : The protective effectes of of glutathione on cisplatin-induced cellular toxicity is more significant in normal lung epithelial cells than in squamous carcinoma cells.

• Journal of agricultural medicine and community health
• /
• v.20 no.1
• /
• pp.39-49
• /
• 1995

This study was attempted to investigate the acceptive status of 428 persons who had taken the vasectomy and the tubal ligation and the intra-uterine device(IUD, copper-T). It defined the complications after the contraceptive procedures and the effects of the supporting of the government for contraception. The target population was identified from the list of the 105 females taken tubal ligation, and 109 males vasectomized, 214 IUD acceptors covered by Gumi Health Center from January 1990 to December 1992. Data was collected from the target population by the questionnaire and medical records between March 1 and April 30, 1993. Among the study subjects, 56.0% of vasectomized males was between 30 and 34 years of age and the highest percentages of tubal ligation and IUD acceptors were between 25 and 29 years of age. The highest percentage of occupation of vasectomized males was officials and that of tubal ligation and IUD acceptors was in no occupational status. 81.2% of respondents were more than high school in educational level, educational level of vasectomized males was more higher than that of females. The percentage contraceptive acceptors with one or two children was 90.8% for vasectomized males, 80.1% for females with tubal ligation, and 93.9% for IUD acceptors. The most people accepted the contraception as they felt the need rather than other's persuasion. The major reasons of contraception were having the wanted children and alleviating the economic burden for the raising and the educating their children. Among the vasectomized males, 11.0% complained the side reaction and the most common symptoms were the inflammation around the wound and sexual declination. Among the tubal ligation females, 46.7% complained the side reaction and the most common symptoms were vaginal discharge, the menorrhagia, back pain and lethargy. The IUD acceptors were similar to them. The regretting rate of tubal ligation and the IUD acceptors was higher than the vasectomized males. The major reason of their regretting was the side reaction in the tubal ligation and the IUD. But the vasectomized males had the insecurity that they couldn't have their own children any more, and sexual declination. The main reason of the females accepted the tubal ligation and the IUD were the fears about toward induced abortion. The most contraceptive acceptors(83.2%) wanted to be offered by the government, but if they pay the expense in their own money, they would accept the contraception in 86.9%.