• Title/Summary/Keyword: History of research

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Ground of the revolutionary change in early 20C American Mathematics (20세기 초 미국수학계의 혁명적변화의 바탕)

  • Lee, Sang-Gu;Hwang, Suk-Geun;Cheon, Gi-Sang
    • Journal for History of Mathematics
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    • v.20 no.3
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    • pp.127-146
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    • 2007
  • From 1876 to 1883, British mathematician James Joseph Sylvester worked as the founding head of Mathematics Department at the Johns Hopkins University which has been known as America's first school of mathematical research. Sylvester established the American Journal of Mathematics, the first sustained mathematics research journal in the United States. It is natural that we think this is the most exciting and important period in American mathematics. But we found out that the International Congress of Mathematicians held at the World's Columbian Exposition in Chicago, August 21-26, 1893 was the real turning point in American's dedication to mathematical research. The University of Chicago was founded in 1890 by the American Baptist Education Society and John D. Rockefeller. The founding head of mathematics department Eliakim Hastings Moore was the one who produced many excellent American mathematics Ph.D's in early stage. Many of Moore's students contributed to build up real American mathematics research power in early 20 century The University also has a well-deserved reputation as the "teacher of teachers". Beginning with Sylvester, we analyze what E.H. Moore had done as a teacher and a head of the new department that produced many mathematical talents such as L.E. Dickson(1896), H. Slaught(1898), O. Veblen(1903), R.L. Moore(1905), G.D. Birkhoff(1907), T.H. Hilderbrants(1910), E.W. Chittenden(1912) who made the history of American mathematics. In this article, we study how Moore's vision, new system and new way of teaching influenced American mathematical society at early stage of the top class mathematical research. and the meaning that early University of Chicago case gave.

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Embryonic Development and Early Life History of the Endangered Species Microphysogobio koreensis (Pisces: Cyprinidae) (멸종위기종 모래주사 Microphysogobio koreensis의 난발생 및 초기생활사)

  • Kim, Chi-Hong;Yoon, Seung-Woon;Kim, Jae-Goo;Kim, Hyun-Tae;Park, Jong-Sung;Park, Jong-Young
    • Korean Journal of Ichthyology
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    • v.24 no.3
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    • pp.160-166
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    • 2012
  • Egg development and early life history of the endangered Korean freshwater fish, Microphysogobio koreensis, was investigated to get a basic information for establishing its conservation strategy. The matured adult fishes were sampled at Imsil-gun, Jeollabuk-do, Korea in May 1 2012 and artificially fertilized. The fertilized eggs were spherical, separated demersal and $1.8{\pm}0.14mm$ in diameter. The hatching of the embryo began at about 29 hours after fertilization under water temperature of $23^{\circ}C$. The newly hatched pre-larvae were average $2.2{\pm}0.48mm$ in total length. At 4 days after hatching, the post-larvae were $3.6{\pm}0.55mm$ in total length and york sac was completely absorbed. At 20 days after hatching, their fin rays were formed and finally the larvae entered juvenile stage and grew up to $6.5{\pm}0.77mm$ in total length. At 60 days after hatching, the total length reached $24.4{\pm}1.71mm$, and the band patterns of he head and lateral side were similar to adult fish. Based on this study, the fertilized eggs of M. koreensis hatched more quickly and the pre-larvae length was also smaller, compared with related species.

Surgical management of a failed internal root resorption treatment: a histological and clinical

  • Asgary, Saeed;Eghbal, Mohammad Jafar;Mehrdad, Leili;Kheirieh, Sanam;Nosrat, Ali
    • Restorative Dentistry and Endodontics
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    • v.39 no.2
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    • pp.137-142
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    • 2014
  • This article presents the successful surgical management of a failed mineral trioxide aggregate (MTA) orthograde obturation of a tooth with a history of impact trauma and perforated internal root resorption. A symptomatic maxillary lateral incisor with a history of perforation due to internal root resorption and nonsurgical repair using MTA was referred. Unintentional overfill of the defect with MTA had occurred 4 yr before the initial visit. The excess MTA had since disappeared, and a radiolucent lesion adjacent to the perforation site was evident radiographically. Surgical endodontic retreatment was performed using calcium enriched mixture (CEM) cement as a repair material. Histological examination of the lesion revealed granulation tissue with chronic inflammation, and small fragments of MTA encapsulated within fibroconnective tissue. At the one and two year follow up exams, all signs and symptoms of disease had resolved and the tooth was functional. Complete radiographic healing of the lesion was observed two years after the initial visit. This case report illustrates how the selection of an appropriate approach to treatment of a perforation can affect the long term prognosis of a tooth. In addition, extrusion of MTA into a periradicular lesion should be avoided.

Relationship Between Perceived Risk and Physician Recommendation and Repeat Mammography in the Female Population in Tehran, Iran

  • Moshki, Mahdi;Taymoori, Parvaneh;Khodamoradi, Sahmireh;Roshani, Daem
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.sup3
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    • pp.161-166
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    • 2016
  • Iranian women are at high risk of low compliance with repeat mammography due to a lack of awareness about breast cancer, negative previous experiences, cultural beliefs, and no regular visits to a physician. Thus research is needed to explore factors associated with repeated mammography participation. Applying the concept of perceived risk as the guiding model, this study aimed to test the fit and strength of the relationship between perceived risk and physician recommendation in explaining repeat mammography. A total of 601 women, aged 50 years and older referred to mammography centers in region 6, were recruited via a convenience sampling method. Using path analysis, family history of breast cancer and other types of cancer were modeled as antecedent perceived risk, and physician recommendation and knowledge were modeled as an antecedent of the number of mammography visits. The model explained 49% of the variance in repeat mammography. The two factors of physician recommendation and breast self-examination had significant direct effects (P < 0.05) on repeat mammography. Perceived risk, knowledge, and family history of breast cancer had significant indirect effects on repeat mammography through physician recommendation. The results of this study provide a background for further research and interventions not only on Iranian women but also on similar cultural groups and immigrants who have been neglected to date in the mammography literature.

Assessment of Risk Factors for Postoperative Delirium in Older Adults Who Underwent Spinal Surgery and Identifying Associated Biomarkers Using Exosomal Protein

  • Baek, Wonhee;Lee, JuHee;Jang, Yeonsoo;Kim, Jeongmin;Shin, Dong Ah;Park, Hyunki;Koo, Bon-Nyeo;Lee, Hyangkyu
    • Journal of Korean Academy of Nursing
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    • v.53 no.4
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    • pp.371-384
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    • 2023
  • Purpose: With an increase in the aging population, the number of patients with degenerative spinal diseases undergoing surgery has risen, as has the incidence of postoperative delirium. This study aimed to investigate the risk factors affecting postoperative delirium in older adults who had undergone spine surgery and to identify the associated biomarkers. Methods: This study is a prospective study. Data of 100 patients aged ≥ 70 years who underwent spinal surgery were analyzed. Demographic data, medical history, clinical characteristics, cognitive function, depression symptoms, functional status, frailty, and nutritional status were investigated to identify the risk factors for delirium. The Confusion Assessment Method, Delirium Rating Scale-R-98, and Nursing Delirium Scale were also used for diagnosing delirium. To discover the biomarkers, urine extracellular vesicles (EVs) were analyzed for tau, ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), neurofilament light, and glial fibrillary acidic protein using digital immunoassay technology. Results: Nine patients were excluded, and data obtained from the remaining 91 were analyzed. Among them, 18 (19.8%) developed delirium. Differences were observed between participants with and without delirium in the contexts of a history of mental disorder and use of benzodiazepines (p = .005 and p = .026, respectively). Tau and UCH-L1-concentrations of urine EVs-were comparatively higher in participants with severe delirium than that in participants without delirium (p = .002 and p = .001, respectively). Conclusion: These findings can assist clinicians in accurately identifying the risk factors before surgery, classifying high-risk patients, and predicting and detecting delirium in older patients. Moreover, urine EV analysis revealed that postoperative delirium following spinal surgery is most likely associated with brain damage.

Assessment of FEMA356 nonlinear static procedure and modal pushover analysis for seismic evaluation of buildings

  • Khoshnoud, Hamid Reza;Marsono, Kadir
    • Structural Engineering and Mechanics
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    • v.41 no.2
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    • pp.243-262
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    • 2012
  • Nonlinear static analysis as an essential part of performance based design is now widely used especially at design offices because of its simplicity and ability to predict seismic demands on inelastic response of buildings. Since the accuracy of nonlinear static procedures (NSP) to predict seismic demands of buildings affects directly on the entire performance based design procedure, therefore lots of research has been performed on the area of evaluation of these procedures. In this paper, one of the popular NSP, FEMA356, is evaluated and compared with modal pushover analysis. The ability of these procedures to simulate seismic demands in a set of reinforced concrete (RC) buildings is explored with two level of base acceleration through a comparison with benchmark results determined from a set of nonlinear time history analyses. According to the results of this study, the modal pushover analysis procedure estimates seismic demands of buildings like inter story drifts and hinges plastic rotations more accurate than FEMA356 procedure.

Characteristics of Directional Orientation in Location and Site Design of Hangae Village, Sungjoo County (성주(星州) 한개마을의 입지(立地)와 배치계획(配置計劃)에 나타난 방위적(防衛的) 특성에 관한 연구)

  • Lee, Hyun-Byung;Kim, Sung-Woo
    • Journal of architectural history
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    • v.13 no.2 s.38
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    • pp.71-81
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    • 2004
  • This paper discusses of the problem of direction and orientation of site design of a traditional Korean village. The research focus on how the directional orientation of each houses adapt the direction of the flow of surrounding mountains. The direction of mountains worked as a prime rule which most of the houses( 76.6%) observed the same direction as their own orientation. While the central part of the village followed the direction of mountains more strictly, however the houses on the periphery area tend to be more free from the direction of mountains. This houses of the periphery respect either the direction of the mountain flow right behind the house or faces toward the south.

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Mammography and Ultrasonography Reports Compared with Tissue Diagnosis - An Evidence Based Study in Iran, 2010

  • Akbari, Mohammad Esmaeil;Haghighatkhah, Hamidreza;Shafiee, Mohammad;Akbari, Atieh;Bahmanpoor, Mitra;Khayamzadeh, Maryam
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.1907-1910
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    • 2012
  • Background: Breast cancer is the most prevalent cancer and the fifth cause of cancer death in Iranian women. Early detection and treatment are important for appropriate management of this disease. Mammography and ultrasonography are used for screening and evaluation of symptomatic cases and the main diagnostic test for breast cancer is pathological. In this study we evaluated mammography and ultrasonography as diagnostic tools. Methods: In this cross-sectional study 384 mammography and ultrasonography reports for 255 women were assessed, divided into benign and malignant groups. Suspected cases were referred for pathology evaluation. The radiologic and pathologic reports were compared and also comparison was performed based on age groups (more and less than 50 years old), history of breastfeeding and gravidity. Statistical analysis was performed by SPSS. Results: The mean ages of malignant and benign cases were $49{\pm}11.6$ and $43{\pm}11.2$ years, respectively. Sensitivity and specificity for mammography were 73% and 45%, respectively. Sensitivity and specificity for ultrasonography were 69% and 49%, respectively. There were statistical differences between specificity of mammography in patients based on factors such as history of gravidity, breastfeeding and sensitivity in patients equal or more than 50 years old and less. Conclusion: Factors affecting different results in mammography and ultrasonography reports were classified into three groups, consisting of skill, experience and training of medical staff, and setting of instruments. It is recommended that health managers in developing countries pay attention the quality of setting and man power more than current status. Policy-makers and managers must establish guidelines regarding breast imaging in Iran.

Comparative Study of Evaluating the Trustworthiness of Data Based on Data Provenance

  • Gurjar, Kuldeep;Moon, Yang-Sae
    • Journal of Information Processing Systems
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    • v.12 no.2
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    • pp.234-248
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    • 2016
  • Due to the proliferation of data being exchanged and the increase of dependency on this data for critical decision-making, it has become imperative to ensure the trustworthiness of the data at the receiving end in order to obtain reliable results. Data provenance, the derivation history of data, is a useful tool for evaluating the trustworthiness of data. Various frameworks have been proposed to evaluate the trustworthiness of data based on data provenance. In this paper, we briefly review a history of these frameworks for evaluating the trustworthiness of data and present an overview of some prominent state-of-the-art evaluation frameworks. Moreover, we provide a comparative analysis of two key frameworks by evaluating various aspects in an executional environment. Our analysis points to various open research issues and provides an understanding of the functionalities of the frameworks that are used to evaluate the trustworthiness of data.