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Trends in Epidemiology, Clinical and Histopathological Characteristics of Breast Cancer in Iran: Results of a 17 Year Study

  • Afsharfard, Aboulfazl;Mozaffar, Mohammad;Orang, Elahe;Tahmasbpour, Eisa
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6905-6911
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    • 2013
  • Background: Breast cancer (BC) is the top cancer among women worldwide and the most frequent malignancy among Iranian women over the past few decades. The increasing trend and high mortality rate of BC in the developing world necessitates studies concentrating on its characteristics in countries in Asia. The current study focused on clinical and histopathological features of BC among Iranian females. Materials and Methods: This retrospective study involved 714 Iranian patients with histopathologically proven BC undergoing resection of primary tumours and axillary clearance. Demographic, clinical and histopathological data were obtained and studied between ten year age groups (${\leq}40$ years, 41-50 years, 51-60 years, 61-70 years, and ${\leq}71$ years) in four chronologic phases from 1994-2009. Results: Mean age of patients was $49.4{\pm}13.1$ years. Most of cases (33.2%) were in 41-50 group. Mean size of primary tumors was $3.94{\pm}2.47$ cm and 87.1% of cases had infiltrative ductal carcinoma. Modified radical mastectomy was the most common method of surgery carried out (48.8%). Some 57.1% of tumors were in pT2 and tumor size decreased significantly during the period (p<0.05). The most common BC stage was llla (27%). Lower BC stages (0 and 1) constituted 13.9% of the diagnosed tumors. Our series of patients aged ${\leq}40$ had larger tumors (mean $4.73{\pm}3.02$ cm) compared to older age groups (p=0.003). Lower stages (0 and I) were more frequent among the oldest patients while nearly 50% of patients aged ${\leq}40$ had tumor stage III. We also observed a significant decreasing trend in the mean LN count (p<0.05) and blood vessel invasion (p=0.023) from younger to older age groups. Conclusions: More aggressive disease for younger age groups, earlier peak incidence age and high rate of advanced BC at the time of diagnosis among Iranian women, were the main findings of this study.

Electrical Characteristics of Copper Circuit using Inkjet Printing (잉크젯 프린팅 방식으로 형성된 구리 배선의 전기적 특성 평가)

  • Kim, Kwang-Seok;Koo, Ja-Myeong;Joung, Jae-Woo;Kim, Byung-Sung;Jung, Seung-Boo
    • Journal of the Microelectronics and Packaging Society
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    • v.17 no.3
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    • pp.43-49
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    • 2010
  • Direct printing technology is an attractive metallization method, which has become immerging as "Green technology" to the conventional photolithography, on account of low cost, simple process and environment-friendliness. In order to commercialize the printed electronics in industry, it is essential to evaluate the electrical properties of conductive circuits using direct printing technology. In this contribution, we focused on the electrical characteristics of inkjet-printed circuits. A Cu nanoink was inkjet-printed onto a Bisaleimide triazine(BT) substrate with parallel transmission line(PTL) and coplanar waveguide(CPW) type, then was sintered at $250^{\circ}C$ for 30 min. We calculated the resistivity of printed circuits through direct current resistance by the measurement of I-V curve: the resistivity was approximately 0.558 ${\mu}{\Omega}{\cdot}cm$ which is about 3.3 times that of bulk Cu. Cascade's probe system in the frequency range from 0 to 30 GHz were employed to measure the Scattering parameter(S-parameter) with or without a gap between the substrate and the probe station chuck. The result of measured S-parameter showed that all printed circuits had over 5 dB of return loss in the entire frequency range. In the curve of insertion loss, $S_{21}$, showed that the PTL type circuits had better transmission of radio frequency (RF) than CPW type.

Comparison of Conflict Level among Administrative Department Staff between Newly Established and Existing University Hospitals (신설 대학병원 행정직원과 기존 대학병원 행정직원의 갈등수준 비교 분석)

  • Kim, Jong-Rae;Yu, Seung-Hum;Sohn, Tae-Yong
    • Korea Journal of Hospital Management
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    • v.3 no.1
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    • pp.62-82
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    • 1998
  • The purpose of this study is to assess the cause and level of conflict arising within and between departments among administration office workers who work in a recently established tertiary hospitals of a major cooperation or related non-profit cooperation: The study also aimed to find methods for resolution of such conflicts by comparing with other existing university hospitals. The subject population included 299 business administration office workers randomly selected from two cooperate related tertiary hospitals of less than 3 years in its existence and two university hospitals over 700 beds in Seoul and Kyong In area. Data were collected through a survey questionnaire. To define related factors for the level of conflict among departments in each hospitals multivariate regression analysis was conducted. Independent factors were characteristics of subjects, conflicting factors within and between the departments. The results are as follows: 1. Those in the 30-39 rears of age group demonstrated significantly higher level of conflict between departments. Those working in the new hospitals, who were older and had long-term tenure, and those with short-term job experience at current working hospital had higher level of conflict between the departments with statistical significance. 2. Concerning the involvement of conflicting factors and the level of conflict in the administration there was statistically significant positive correlation between reliability and job-related intra- and interdepartmental level of conflict in existing hospitals. There was a significant positive correlation between intradepartmental conflicting factors of mutual dependence, difference in goal/orientation and intra- and interdepartmental level of conflict. 3. In multivariate regression analysis, women more than men, and those who had worked for many years in hospitals had statistically significant influence on factors involved in interdepartmental level of conflict, explaining 51.0% of the model. 4. In existing hospitals, gender was a significant factor with women showing a higher level of interdepartmental conflict compared to men. Among the interdepartmental factors, mutual dependence had statistically significant influence and showed a positive relationship with interdepartmental level of conflict. In the new hospitals, job position was a significant factor which showed that those in high position such as section chief or above, compared to those in managerial or general position had higher level of conflict. Among the interdepartmental characteristics, factors of mutual dependence and goal/orientation had statistically significant influence and showed a positive relationship with interdepartmental level of conflict. In the new hospital setting efforts to reduce conflict in areas among workers with high position, old age, and long tenure and those in Purchasing, Material and Computer Department should be made and prudent management and planning for improved manpower and increased budget or efficient allocation and clear definition of job description are necessary to adequately assess and make improved efforts for rapid stabilization of the premature hospital system from its inception, In the existing hospitals a lack of conflict within and between departments may give rise to stagnation or inefficiency of the organization. Future study are needed with respect to the relationship between interdepartmental level of conflict and the effectiveness of the hospital organization for improved resolution of conflict in the organization and hospital management.

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Fundamental Study on the Application of a Surface Layer using Cold Central-Plant Recycling (플랜트 생산 재활용 상온 혼합물의 도로 표층 적용성에 관한 기초연구)

  • Choi, Jun Seong
    • International Journal of Highway Engineering
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    • v.20 no.1
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    • pp.69-76
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    • 2018
  • PURPOSES : This study determined the optimal usage rate of RAP (reclaimed asphalt pavement) using cold central-plant recycling (CCPR) on a road-surface layer. In addition, a mixture-aggregate gradation design and a curing method based on the proposed rate for the surface-layer mix design were proposed. METHODS : First, current research trends were investigated by analyzing the optimum moisture content, mix design, and quality standards for surface layers in Korea and abroad. To analyze the aggregate characteristics of the RAP, its aggregate-size characteristics were analyzed through the combustion asphalt content test and the aggregate sieve analysis test. Moreover, aggregate-segregation experiments were performed to examine the possibility of RAP aggregate segregation from field compaction and vehicle traffic. After confirming the RAP quality standards, coarse aggregate and fine aggregate, aggregate-gradation design and quality tests were conducted for mixtures with 40% and 50% RAP usage. The optimum moisture content of the surface-layer mixture containing RAP was tested, as was the evapotranspiration effect on the surface-layer mixture of the optimum moisture content. RESULTS : After analyzing the RAP recycled aggregate size and extraction aggregate size, 13-8mm aggregate was found to be mostly 8mm aggregate after combustion. After using surface-chipping and mixing methods to examine the possibility of RAP aggregate segregation, it was found that the mixing method contributed very little for 3.32%, and because the surface-chipping method applied compaction energy directly as the maximum assumption the separation ratio was 15.46%. However, the composite aggregate gradation did not change. Using a 40% RAP aggregate rate on the surface-layer mixture for cold central-plant recycling satisfied the Abroad quality standard. The optimum moisture content of the surface-layer mixture was found to be 7.9% using the modified Marshall compaction test. It was found that the mixture was over 90% cured after curing at $60^{\circ}C$ for two days. CONCLUSIONS : To use the cold central-plant recycling mixture on a road-surface layer, a mixture-aggregate gradation design was proposed as the RAP recycled aggregate size without considering aggregate segregation, and the RAP optimal usage rate was 40%. In addition, the modified Marshall compaction test was used to determine the optimum moisture content as a mix-design parameter, and the curing method was adapted using the method recommended by Asphalt Recycling & Reclaiming Association (ARRA).

The Frost Heaving Characteristics of Subgrade Soils Using Laboratory Freezing System (실내동결시스템을 이용한 노상토의 동상 특성)

  • Shin, Eun-Chul;Ryu, Byung-Hyun;Park, Jeong-Jun
    • International Journal of Highway Engineering
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    • v.12 no.2
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    • pp.71-79
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    • 2010
  • The influence of fines of the frost susceptibility of subgrade soils were established by laboratory freezing system test simulating closely the thermal conditions in the field. During the winter season, the climate is heavily influenced by the cold and dry continental high pressure. Because of siberian air mass, the temperature of January is $-6{\sim}-7^{\circ}C$ on average. This chilly weather generate the frost heaving by freezing the moisture of soil and damage potential of the road structure. In the freezing soil, the ice lenses increase the freeze portion of soil by absorbing the ground water with capillary action. However, the capillary characteristics differ from the sort of soil on the state of freezing condition. In the current design codes for anti-freezing layer, the thickness of anti freezing layer is calculated by freezing depth against the temperature condition. Therefore, they have a tendency of over-design and uniform thickness without the considerations of thermal stability, bearing capacity and frost susceptibility of materials. So, it is essential for studying the appropriateness and bearing capacity besides the seasonal and mechanical properties of pavement materials to take a appropriate and reasonable design of the road structure. In this Paper, the evaluation of frost susceptibility was conducted by means of the mechanical property test and laboratory freezing system apparatus. The temperature, heaving amount, heaving pressure and unfrozen water contents of soil samples, the subgrade soils of highway construction site, were measured to determine the frost susceptibility.

Types and Characteristics of Primary Teachers' Instructional Expertise Development Activities for Software Education (초등 교사의 SW교육 수업 전문성 개발 활동 형태 및 특성)

  • Ock, Jihyun;Ahn, Seongjin
    • Journal of The Korean Association of Information Education
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    • v.22 no.5
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    • pp.519-533
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    • 2018
  • This study aims to classify the types of instructional expertise development activities of teachers who teach subjects related to software education in primary schools. To this end, the study analyzes their participation in expertise development activities over the recent three years, outcomes from these activities, and forms and characteristics of expertise development activities. In the questionnaire survey conducted for this study, 276 primary school teachers participated. According to the survey, the same largest proportion of them participated in collective job training (96%) and distant job training (96%), followed by consulting, instruction supervision, mentoring, and peer observation (82%), lectures, workshops, and seminars held by related government ministries and the provincial and municipal offices of education (69%), and teachers' study communities (66%). Among informal activities, reading accounted for the highest portion of the activities (88%), followed by the use of information on Websites including YouTude and GitHub (80%), and teachers' expertise development networks (76%). The reasons for their participation in the activities were mostly to improve their instructional expertise (80%). Their participation in the activities had an impact on usefulness to enhance instructional expertise, improvement of job competencies, application to current jobs, sense of instructional efficacy, and positive effect. These results of the study are expected to provide a foundation for preparing continued expertise development plans that can promote the educational value of primary school teachers' instructional expertise development activities for teaching subjects related to software education.

A Study on the Characteristics of the Spatial Distribution of Sex Crimes: Spatial Analysis based on Environmental Criminology (성폭력 범죄의 공간적 분포 특성에 관한 연구: 환경범죄학에 기반한 공간 분석)

  • Lee, Gunhak;Jin, Chanwoo;Kim, Jiwoo;Kim, Wanhee
    • Journal of the Korean Geographical Society
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    • v.51 no.6
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    • pp.853-871
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    • 2016
  • The interest in the prevention of sex crimes and social secure is growing as the number of cases by sexual offences becomes higher. Although various punishable ways have been introduced so far, increasing sex crime is still going on. Thus, effectiveness of legal systems for preventing crimes is questionable. More recently, the approach for environmental criminology has been paid attention for reducing criminal opportunities through environmental design and management of crimes. This study attempts to look over the spatial distribution of sexual crimes in the context of environmental criminology, and examine the correlation between regional environmental factors and the occurrence of sexual crimes empirically. To do this, we visualized the map for sex crimes at the macro-scale and explored the spatial distribution of sexual crimes and spatial clusters based on various spatial statistics using sex crime data published online by the ministry of gender equality and family. Also, we derived the environmental characteristics of sexual crimes by multivariate regression analysis on a large number of explanatory variables of regional environment. Our results will help to understand the current situation and spatial aspects of sex crimes in the nation more realistically. Further, it is respected that our results might be useful basic information for establishing regional policies and plans for the prevention of the sexual crime and enhanced public policing.

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A Parametric Study of Pulsed Gamma-ray Detectors Based on Si Epi-Wafer (실리콘 에피-웨이퍼 기반의 펄스감마선 검출센서 최적화 연구)

  • Lee, Nam-Ho;Hwang, Young-Gwan;Jeong, Sang-Hun;Kim, Jong-Yeol;Cho, Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.7
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    • pp.1777-1783
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    • 2014
  • In this paper, we designed and fabricated a high-speed semiconductor sensor for use in power control devices and analyzed the characteristics with pulsed radiation tests. At first, radiation sensitive circular Si PIN diodes with various diameters(0.1 mm ~5.0 mm) were designed and fabricated using Si epitaxial wafer, which has a $42{\mu}m$ thick intrinsic layer. The reverse leakage current of the diode with a radius of 2 mm at a reverse bias of 30 V was about 20.4 nA. To investigate the characteristic responses of the developed diodes, the pulsed gamma-radiation tests were performed with the intensity of 4.88E8 rad(Si)/sec. From the test results showing that the output currents and the rising speeds have a linear relationship with the area of the sensors, we decided that the optimal condition took place at a 2 mm diameter. Next, for the selected 2 mm diodes, dose rate tests with a range of 2.47E8 rad(Si)/sec to 6.21E8 rad(Si)/sec were performed. From the results, which showed linear characteristics with the radiation intensity, a large amount of photocurrent over 60mA, and a high speed response under 350ns without saturation, we can conclude that the our developed PIN diode can be a good candidate for the sensor of power control devices.

Identification of ecological characteristics of Deciduous broad-leaved forest, Garasan(Mt.)·Nojasan(Mt.) at GeoJae (거제도 가라산·노자산 일대 낙엽활엽수림의 생태적 특성 규명)

  • Lee, Soo-Dong;Cho, Bong-Gyo;Lee, Gyounggyu;Yeum, Jung-Hun;Oh, Chung-Hyeon
    • Korean Journal of Environment and Ecology
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    • v.35 no.2
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    • pp.204-219
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    • 2021
  • This study was conducted to investigate and analyze the characteristics of the plant community structure of vegetation distributed on the western slope and ridge connecting Mt. Noja to Mt. Gara. This basic research was executed not only to restore and manage forest vegetation, but also to monitor the trend of change in the long term. As a result of classifying the communitise in 86 survey quadrats, the Pinus thunbergii-Platycarya strobilacea comm. and P. thunbergii-P. densiflora comm. were distributed around the lowlands. The Carpinus tschonoskii-Deciduous broad-leaved comm., Styrax japonicus-Deciduous broad-leaved comm., Acer pictum subsp. Mono-Deciduous broad-leaved comm., Deciduous broad-leaved comm., and Zelkova serrata comm. appeared in the valley and all stone areas. Quercus serrata comm., Q. serrata-S. japonicus comm., S. japonicus-Carpinus cordata comm., Euonymus oxyphyllus comm. were classified as being distributed on steep slopes with relatively high altitude. According to the succession trend of the forest, evergreen conifers will be transition to deciduous broad-leaved trees. However, deciduous broad-leaved arboreous forests, such as Carpinus tschonoskii, zelkova serrata, and Acer pictum subsp. Mono, were considered to maintain their current succession stage because not only the stratified structure was developed over about 50 years tree age, but also ecologically stabilized. As environmental factors, it was analyzed that altitude, pH, content of clay and silt, Mg++, Ca++, etc. directly or indirectly affect the distribution of plant communities.

An Analysis of Domestic Research Trends on Museum Lighting (박물관 조명에 관한 국내 연구 동향 분석)

  • Kim, Jiwon;Kang, Daiill
    • Korean Journal of Heritage: History & Science
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    • v.52 no.3
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    • pp.188-199
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    • 2019
  • In this study, research trends were investigated by examining important academic research on museum lighting that has been carried out in Korea over the past 30 years. The aim was to highlight important studies conducted in Korea on material deterioration caused by museum lighting and to examine the current status of research on LED light sources to provide direction for future research. The ultimate goal of studies on museum lighting is to improve the long-term conservation effects, and this study examined the latest light sources of each era. Prior to the 1990s, the effects of light sources on relics were assessed by investigating incandescent light bulbs and fluorescent lamps, the first museum exhibition lighting. Then in the 1990s, the introduction of halogen lamps and HID lamps led to the analysis of the characteristics of a light source itself and the introduction of illumination standards. In the 2000s, the lighting environment of museums was investigated based on the characteristics of the light sources that had been studied, and in terms of preservation, research was conducted not only to improve the conservation of relics but also to improve the sentiments of visitors. After 2010, LED lamps were introduced; therefore, material deterioration studies on LED lamps were expanded. During this period, enhancements to LED light sources were made, such as reducing the blue spike area and increasing color rendering. With the development of lighting used in museums and art galleries, the direction of the display preservation criteria has led to the need to prepare advanced standards, covering all aspects from the center of illumination to the consideration of the color of an object and the speed of radiation from the light source. Regular studies of museum lighting in a long-term perspective should be planned to standardize the more advanced conditions of material discoloration.