• Title/Summary/Keyword: scientific examination

Search Result 216, Processing Time 0.027 seconds

A Study on the Analysis of Population Dynamics and the Model of population Relocation (人口過程의 分析과 人口配置計劃의 모델模索)

  • 박찬계;함종욱
    • Journal of the Korean Statistical Society
    • /
    • v.10
    • /
    • pp.145-157
    • /
    • 1981
  • Regional relocation of population in Korea is required strongly from natural and environmental sides for substantial growth of economy and the rigorous revival national economy against especially internationalization. This paper aimed for analysed the population distribution by regional and special characteristics of the inter-migration and showed the direction of population policy through the model building. Relocation methods of population by region has been examined through the process from the approach method by Haurin's production function to the approach by the utility function. The examination of the development model is done efficiently, how utility these approach models are depends on that scientific and composite plan for population problems against forced policy should be taken precedence.

  • PDF

The Advent of Cuffless Mobile Device Blood Pressure Measurement: Remaining Challenges and Pitfalls

  • Hae-Young Lee;Thilo Burkard
    • Korean Circulation Journal
    • /
    • v.52 no.3
    • /
    • pp.198-204
    • /
    • 2022
  • Blood pressure measurement (BPM) is an essential part of medical examination, and therefore accuracy of BPM devices is crucial. Over the past few years, there has been a rise in new BPM techniques using photoplethysmographic (PPG) signals and complex algorithms for blood pressure estimation. Especially the combination of a mobile device or a smartphone with a camera using PPG may potentially revolutionize BPM in the future. The first-ever BPM application to be approved as a medical device was one by the Korean Ministry of Food and Drug Safety in 2020, despite the lack of robust scientific evidence proving its validity. While the prospect of using these novel BPM devices is an opportunity, there are also some critical issues around calibration and utility in different patient groups that need to be resolved before they can be incorporated into daily clinical practice.

Effect of quartic nonlinearity on elastic waves via successive approximation

  • Hamza Hameed;F. D. Zaman
    • Advances in materials Research
    • /
    • v.13 no.4
    • /
    • pp.285-297
    • /
    • 2024
  • The theory of nonlinear elastic wave propagation is important in multiple scientific and engineering fields. In this study, we present a comprehensive examination of nonlinear elastic wave profiles through a contemporary approach of successive approximation. This research is related to nonlinear elastic wave models along different types of nonlinearities. Murnaghan potential is used due to the assumption of the hyper-elastic materials. We explore the complication of the governing equations and go through the behaviors of nonlinear waves in one dimension. The comparative aspect of our study is a distinctive feature, as we evaluate and contrast the results obtained using successive approximation along different nonlinearities. Additionally, we present graphical representations of our findings, enhancing the visual comprehension of the wave profiles and their evolution. This study contributes to the nonlinear elastic wave analysis and comparison.

Law, Theory, and Principle: Confusion in the Normative Meaning and Actual Usage (법칙, 이론, 그리고 원리: 규범적 의미와 실제사용에서의 혼란)

  • Cheong, Yong Wook
    • Journal of The Korean Association For Science Education
    • /
    • v.34 no.5
    • /
    • pp.459-468
    • /
    • 2014
  • Educational Discourses on the nature of science(NOS) identify understanding of the role of scientific knowledge, especially the distinction between law and theory, as a crucial goal of instruction. However, the scientist community uses the terms such as law, theory, and principle without explicit definition so that the terms have no coherent meanings in their conventional language expression. The inconsistency between the norm and the reality could impose confusion on the teaching and learning. From the awareness of the problem, this study critically reviews the science education research papers and literatures on the philosophy of science which focus on the meaning of law, theory, or principle and the structure of scientific knowledge. From the examination of the science education researches, it is revealed that the disparity between the normative meanings of the law and theory by NOS researchers and actual usage of the terms is quite serious. From the review of the literatures of the philosophy of science, the necessity of the distintion of three categories: law, theory, and principle beyond the dichotomy between law and theory is brought up. By synthesizing the related literatures, we provide an outline of the characteristics of knowledges belonging to law, theory, and principle. Considering the conflict between the normative definition and the conventional language, it could be unnecessary to emphasize clear distinction on the terms as an instructional goal. Instead, the goal of instruction should focus on that there are three types of scientific knowledges of different functions and characteristics.

Taxonomic examination of Typha angustifolia L. in Korea (한국산 애기부들에 대한 분류학적 검토)

  • Kim, Changkyun;Shin, Hyunchur;Choi, Hong-Keun
    • Korean Journal of Plant Taxonomy
    • /
    • v.31 no.4
    • /
    • pp.359-373
    • /
    • 2001
  • One of Korean Typha species has been used two scientific names, T. angustifolia L. and T. angustata Bory et Chaubard without taxonomic examinations. Typha angustifolia has a longer females flowers than bracteoles and equal length of bracteoles and hairs in female flowers whereas T. angustata has equal length of female flowers and bracteoles and longer bracteloes than hairs in female flowers. In this study, the pattern of morphological variation of T. angustifolia in Korea is examined using numerical analysis to determine their taxonomical identities. Univariate analysis using morphological characters such as female flower length/bracteole length and bracteole lengh/hair length reveals that Korean T. angustifolia is composed of one group. The result of principal components analysis shows that Korean T. angustifolia is closely related to T. angustifolia distributed in Japan, Russia, and USA. Therefore, T. angustifolia L. (in Korea) is suggested as a legitimate scientific name.

  • PDF

Prestige and Expanding Scope of Korean Dentistry- Dr. Jong-Suh Ahn (권위와 외연의 확장-치과의사 안종서)

  • Shin, Jae Eui
    • The Journal of the Korean dental association
    • /
    • v.50 no.8
    • /
    • pp.482-506
    • /
    • 2012
  • Dentists have been striving to find ways to relieve patients' pain and discomfort. The prestige of dentists is made up of dentists' self-sacrifice, academic research and pursuit of patients' well being. However, nowadays the dentists' prestige has been lost and practice on humanity has merely existed. At this time, it is meaningful to shed new light on life of a pioneer in Korean dentistry and take some time for self-examination. Today, we are going to look into life of Dr. Jong-Suh Ahn and his achievements in Korean dentistry. In 1925, Dr. Ahn Jong Suh graduated from KyungSung Dental school as a first graduating class. Then, he learned advanced dentistry at Severance Hospital and in April of 1932 as a young dentist with full of potentials, he opened his dental clinic in Tianjin, China. As an awakening Korean, in 1925 he organized an association of Korean dentists, called HanSung Dental Association and worked as a secretary to manage general affairs. Han Sung Dental Association later became today's Korean Dental Association. On December 9th, 1945, he founded ChoSun Dental Association. He accomplished great deals during his five consecutive terms as a chairman and held other important positions with prestige to lead and expand the scope Korean dental association. There were three other successors to Dr. Ahn as the presidents of Dental Association. Dr. Yong-Jin Kim had a great interest in internal affairs and dental materials. Dr. Myung-Jin Park was active in scientific affairs and Dr. Dong-Chan Han focused on smooth operation of the association. From 1945 to 1963, Dr. Ahn submitted important agendas such as dentist's qualification, scientific and academic affairs, general affairs, dental materials, public oral health, and dental administration to Dental Association's general meeting and central committee. Dr. Ahn overcame hardships of Japanese imperialism, celebrated independence of Korea, experienced 6.25 Korean War and lived through evolving Korean dentistry in 1960s. Dr. Jong-Suh Ahn, who showed the prestige of dentist and expanded the scope of dental association, is exemplary to all dentists.

Curcumin Reorganizes miRNA Expression in a Mouse Model of Liver Fibrosis

  • Hassan, Zeinab Korany;Al-Olayan, Ebtisam M.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.11
    • /
    • pp.5405-5408
    • /
    • 2012
  • Curcumin (CM), a biphenyl compound, possesses anti-inflammatory, antioxidant and antimicrobial activity. MicroRNAs (miRNAs) are small noncoding RNAs which regulate gene expression and the molecular mechanisms of several biological processes. Liver fibrosis is a major cause of hepatic dysfunction and cancer and there are few effective therapies emphasizing the need for new approaches to control. The present study was conducted to investigate the effect of curcumin (CM) on liver fibrosis through modulating the expression level of miRNAs (199 and 200), the main miRNAs associated with liver fibrosis. Induction of liver fibrosis by carbon tetrachloride ($CCL_4$) was confirmed by histopathological examination. Mice were divided into 3 groups: group 1 were i.p injected with 10% $CCL_4$ twice weekly for 4 weeks and then once a week for the next 4 weeks followed by 4 weeks with olive oil only. Group 2 were i.p injected with 10% $CCL_4$ twice weekly for 4 weeks and then once a week for the next 4 weeks followed by curcumin (5 mg/mouse/day) once daily for the next 4 weeks. The third group was injected with olive oil. The expression level of miR-199 and miR-200 and some of their targeted genes were measured by real time PCR. miRNA (199 and 200) levels were significantly elevated in liver fibrotic tissues compared to control groups. Curcumin was significantly returned the expression levels of mir-199 and -200 with their associated target gene nearly to their normal levels. This is the first study that highlighted the effect of curcumin on liver fibrosis through regulation of miRNAs.

The Effect of Elementary Science Teaching Program with Circle Map on Learning Motive and Learning Achievement (Circle Map를 활용한 초등학교 과학수업이 학습 동기와 학업성취도에 미치는 영향)

  • HONG, Yu Kyoung;LEE, Seok Hee
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.29 no.3
    • /
    • pp.799-810
    • /
    • 2017
  • In this study, to raise the scientific literacy for students, the teaching and learning program was developed by applying the Circle Map. The purpose of this study was to find out the Effect of Elementary Science Teaching Program with Circle Map on Learning Motive and Learning Achievement. To this end, the 6th grade classroom of A-elementary school located in Jeju-city was selected the experimental group (25 patients). And the other 6th grade classroom in the same school was selected to the comparative group (25 patients). The experimental group was conducted applying the Circle Map. Comparison group has been conducted lesson program in accordance with the general science class teacher guide. Was through a pre-test of science learning motivation and academic achievement level can be assumed in the same group. After completing the experimental treatment by conducting a post-mortem examination was statistically validated. In this study, the following conclusions were obtained. First, elementary science class which applied Circle Map had the effect of to improve the scientific motivation(p <.05). In particular, association in the experimental group were higher than the scores of the comparative group, the difference was significant. Second, the Circle Map applied to elementary science class had a significant effect on improving science achievement. The experimental group which applied Circle Map was higher than the comparative group in science achievement post-test comparison. Between the groups showed a significant difference between the two groups(p <.05). The above findings, Elementary science class which applied Circle Map can be concluded to be effective in science and science achievement motivation. Therefore, applying the Circle Map of elementary science class could be useful in science teaching and learning methods. In addition, when it is determined through the previous study, applying the Circle Map classes will be able to derive a meaningful learning also subjected to a number of fields and areas.

The Role of Stem Cells and Gap Junctional Intercellular Communication in Carcinogenesis

  • Trosko, James E.
    • BMB Reports
    • /
    • v.36 no.1
    • /
    • pp.43-48
    • /
    • 2003
  • Understanding the process of carcinogenesis will involve both the accumulation of many scientific facts derived from molecular, biochemical, cellular, physiological, whole animal experiments and epidemiological studies, as well as from conceptual understanding as to how to order and integrate those facts. From decades of cancer research, a number of the "hallmarks of cancer" have been identified, as well as their attendant concepts, including oncogenes, tumor suppressor genes, cell cycle biochemistry, hypotheses of metastasis, angiogenesis, etc. While all these "hallmarks" are well known, two important concepts, with their associated scientific observations, have been generally ignored by many in the cancer research field. The objective of the short review is to highlight the concept of the role of human adult pluri-potent stem cells as "target cells" for the carcinogenic process and the concept of the role of gap junctional intercellular communication in the multi-stage, multi-mechanism process of carcinogenesis. With these two concepts, an attempt has been made to integrate the other well-known concepts, such as the multi-stage, multi-mechanisn or the "initiation/promotion/progression" hypothesis; the stem cell theory of carcinogenesis; the oncogene/tumor suppression theory and the mutation/epigenetic theories of carcinogenesis. This new "integrative" theory tries to explain the well-known "hallmarks" of cancers, including the observation that cancer cells lack either heterologous or homologous gap junctional intercellular communication whereas normal human adult stem cells do not have expressed or functional gap junctional intercellular communication. On the other hand, their normal differentiated, non-stem cell derivatives do express connexins and express gap junctional intercellular communication during their differentiation. Examination of the roles of chemical tumor promoters, oncogenes, connexin knock-out mice and roles of genetically-engineered tumor and normal cells with connexin and anti-sense connexin genes, respectively, seems to provide evidence which is consistent with the roles of both stem cells and gap junctional communication playing a major role in carcinogenesis. The integrative hypothesis provides new strategies for chemoprevention and chemotherapy which focuses on modulating connexin gene expression or gap junctional intercellular communication in the premalignant and malignant cells, respectively.

Surface Analysis of Modified Polymer Samples by X-Ray Photoelectron Spectroscopy and Rutherford Backscattering Spectroscopy (X-선 광전자 분광법 및 라더포드 후방산란법에 의한 개질된 고분자 시료의 표면분석)

  • Park, Sung-Woo;Kim, Dong-Hwan;Kim, Young-Man;Park, Byung-Sun;Han, Wan-Soo;Suh, Bae-Suk
    • Analytical Science and Technology
    • /
    • v.7 no.3
    • /
    • pp.301-313
    • /
    • 1994
  • X-Ray Photoelectron Spectroscopy(XPS) and Rutherford Backscattering Spectroscopy(RBS) are used for the analysis of additives, examination of chemical structure and determination of identity with qualitative and quantitative analysis of surface elements, binding energy level and depth profiling in the surface. We analyzed surface of polyethylene, acrylonitrile butadien rubber, polypropylene, glass, fiber and paper treated with $XeF_2$ or C-F plasma by XPS and RBS. It was found that fluoro element was penetrated to sample surface and the distribution of surface elements are different than untreated samples.

  • PDF