• Title/Summary/Keyword: prior studies

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Clinical Significance of PCR-Based Rapid Detection of Mycobacterium tuberculosis DNA in Peripheral Blood (결핵 환자에서 말초혈액 결핵균 중합효소 연쇄반응 양성의 임상적 의의)

  • Kim, Gyu-Won;Lee, Jae-Myung;Kang, Min-Jong;Son, Jee-Woong;Lee, Seung-Joon;Kim, Dong-Gyu;Lee, Myung-Goo;Hyun, In-Gyu;Jung, Ki-Suck;Lee, Young-Kyung;Lee, Kyung-Wha
    • Tuberculosis and Respiratory Diseases
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    • v.50 no.5
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    • pp.599-606
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    • 2001
  • Background : Since the advent of AIDS, tuberculosis has become a major public health problem in the western society. Therefore, it is essential that pulmonary tuberculosis be rapidly diagnosed. Light microscopic detection of acid-fast organisms in sputum has traditionally been used for rapidly diagnosing tuberculosis. However positive smears are only observed in about one-half to three-quarters of cases. Studies using PCR for diagnosing pulmonary tuberculosis disclosed several shortcomings suggesting an inability to distinguish between active and treated or inactive tuberculosis. In this study, the clinical significance of a PCR-based rapid technique for detecting Mycobacterium tuberculosis DNA in peripheral blood was investigated. Materials and Methods : From July 1, 1998 through to August 30, 1999, 59 patients with presumed tuberculosis, who had no previous history of anti-tuberculosis medication use within one year prior to this study were recruited and followed up for more than 3 months. AFB stain and culture in the sputum and/or pleural fluids and biopsies when needed were performed. Blood samples from each of the 59 patients were obtained in order to identify Mycobacterium Tuberculosis DNA by a PCR test. Results : 1) Forty five out of 59 patients had a final diagnosis of tuberculosis ; Twenty eight were confirmed as having active pulmonary tuberculosis by culture or biopsy. Four were clinically diagnosed with pulmonary tuberculosis. The other 13 patients were diagnosed as having tuberculous pleurisy (9) and extrapulmonary tuberculosis (4). 2) Fourteen patients showed a positive blood PCR test. The PCR assay correctly identified active tuberculosis in 13 out of 14 patients. The overall sensitivity and specificity of this blood peR assay for diagnosing tuberculosis were 29% and 93%, respectively. The positive predictive value was 93%, the negative predictive value was 29% and the diagnostic accuracy was 44%.3) Six out of 14(43%) patients with blood PCR positive tuberculosis were immunologically compromised hosts. 4) A simple chest radiograph in blood PCR positive tuberculosis patients showed variable and inconsistent findings. Conclusion : A peripheral blood PCR assay for Mycobacterium tuberculosis is not recommended as a screening method for diagnosing active tuberculosis. However, it was suggested that the blood PCR assay could contribute to an early diagnostic rate due to its high positive predictive value.

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The Differentiation of Malignant and Benign Musculoskeletal Tumors by F-18 FDG PET/CT Studies - Determination of maxSUV by Analysis of ROC Curve (F-18 FDG PET/CT에서 양성과 악성 근골격 종양의 감별진단 - 수신자 판단특성곡선을 이용한 maxSUV의 절단값 결정)

  • Kong, Eun-Jung;Cho, Ihn-Ho;Chun, Kyung-Ah;Won, Kyu-Chang;Lee, Hyung-Woo;Choi, Jun-Heok;Shin, Duk-Seop
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.6
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    • pp.553-560
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    • 2007
  • Purpose: We evaluated the standard uptake value (SUV) of F-18 FDG at PET/CT for differentiation of benign from malignant tumor in primary musculoskeletal tumors. Materials and Methods: Forty-six tumors (11 benign and 12 malignant soft tissue tumors, 9 benign and 14 malignant bone tumors) were examined with F-18 FDG PET/CT (Discovery ST, GE) prior to tissue diagnosis. The maxSUV(maximum value of SUV) were calculated and compared between benign and malignant lesions. The lesion analysis was based on the transverse whole body image. The maxSUV with cutoff of 4.1 was used in distinguishing benign from malignant soft tissue tumor and 3.05 was used in bone tumor by ROC curve. Results: There was a statistically significant difference in maxSUV between benign (n=11; maxSUV $3.4{\pm}3.2$) and malignant (n=12; maxSUV $14.8{\pm}12.2$) lesions in soft tissue tumor (p=0.001). Between benign bone tumor (n=9; maxSUV $5.4{\pm}4.0$) and malignant bone tumor (n=14; maxSUV $7.3{\pm}3.2$), there was not a significant difference in maxSUV. The sensitivity and specificity for differentiating malignant from benign soft tissue tumor was 83% and 91%, respectively. There were four false positive malignant bone tumor cases to include fibrous dysplasia, Langerhans-cell histiocytosis (n=2) and osteoid osteoma. Also, one false positive case of malignant soft tissue tumor was nodular fasciitis. Conclusion: The maxSUV was useful for differentiation of benign from malignant lesion in primary soft tissue tumors. In bone tumor, the low maxSUV correlated well with benign lesions but high maxSUV did not always mean malignancy.

A Study of Long-term Trends of SST in the Korean Seas by Reconstructing Historical Oceanic Data (과거 해양자료 복원을 통한 한반도 주변해역 표층수온의 장기변동 연구)

  • Park, Myung-Hee;Song, Ji-Young;Han, In-Seong;Lee, Joon-Soo
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.25 no.7
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    • pp.881-897
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    • 2019
  • We reconstructed and digitized the National Institute of Fisheries Science (NIFS) Serial Oceanographic observations (NSO) and Coastal Oceanographic observations (NCO) data attained prior to 1961 through historical oceanographic observation data rescue projects. Increasing trends of long-term sea surface temperature (SST) were shown from the NSO data of 21 available stations for the past 80 to 92 years. In general agreement with previous research results used in the data of the past 50 years, we calculated the rate of temperature rise. As a result of analyzing the spatial distribution of SST change rate in the Korean of shore region using selected oceanographic data, the West Sea and South Sea showed a higher tendency of temperature rise in the offshore area than in the coastal area. However, unlike the results of previous studies, the East Sea (Gangwon Line and Ulsan Line) showed a lower water temperature rise than the coastal stations. Annual fluctuations of NCO's SST data from 1989 to 1998 for three stations representing the East Sea, South Sea, and West Sea, (Jumunjin, Geomundo and Budo, respectively) revealed that the East Sea showed the highest SST increase for the 10 years. The increases were 1.63 ℃ at Jumunjin, 1.16 ℃ at Geomundo, and 0.79 ℃ at Budo. As a result of the investigation, it can be concluded that SST is repeatedly rising and falling with a period of 3 ~ 6 years. Especially, since the 1980s, most of the stations show positive anomalies of SST. Lastly, to understand ocean_atmosphere interactions, we analyzed the correlations between SST of the NCO stations and air temperature around them and the results were 0.76 for the South Sea (Geomundo), 0.34 for the West Sea (Budo), and 0.32 for the East Sea (Jumunjin) with the highest correlation in the South Sea.

Charaterization of Biomass Production and Wastewater Treatability by High-Lipid Algal Species under Municial Wastewater Condition (실제 하수조건에서 고지질 함량 조류자원의 생체생성과 하수처리 특성 분석)

  • Lee, Jang-Ho;Park, Joon-Hong
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.4
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    • pp.333-340
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    • 2010
  • Wastewater treatment using algal communities and biodiesel production from wastewater-cultivated algal biomass is a promising green growth technology. In literature, there are many studies providing information on algal species producing high content of lipid. However, very little is known about adaptability and wastewater treatability of such high-lipid algal species. In this study, we attempted to characterize algal biomass production and wastewater treatability of high-lipid algal species under municipal wastewater condition. For this, four known high-lipid algal strains including Chlorella vulgaris AG 10032, Ankistrodesmus gracilis SAG 278-2, Scenedesmus quadricauda, and Botryococcus braunii UTEX 572 were individually inoculated into municipal wastewater where its indigenuous algal populations were removed prior to the inoculation, and the algae-inoculated wastewater was incubated in the presence of light source (80${\mu}E$) for 9 days in laboratory batch reactors. During the incubations, algal biomass production (dry weight) and the removals of dissolved organics (COD), nitrogen and phosphorous were measured in laboratory batch reactors. According to algal growth results, C. vulgaris, A. gracilis and S. quadricauda exhibited faster growth than indigenuous wastewater algal populations while B. braunii did not. The wastewater-growing strains exhibited efficient removals of total-N, ${NH_4}^+$-N, Total-P and ${PO_4}^{3-}$-P which satisfy the Korea water quality standards for effluent from municipal wastewater treatment plants. A. gracilis and S. quadricauda exhibited efficient and stable treatability of COD but C. vulgaris showed unstable treatability. Taken together with the results, A. gracilis and S. quadricauda were found to be suitable species for biomass production and wastewater treatment under municipal wastewater condition.

Ground Security Activities for Prevention of Aviation Terrorism -Centered on San Francisco International Airport of the U.S.A.- (항공테러방지를 위한 지상 보안활동 -미국 샌프란시스코국제공항을 중심으로-)

  • Kang, Maeng-Jin;Kang, Jae-Won
    • The Journal of the Korea Contents Association
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    • v.8 no.2
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    • pp.195-204
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    • 2008
  • With the growth of airline management, as well as computer and IT security, the international trade in this modern society has been rapidly increasing, Along with the advancing, airplanes have become a universal means of communication. However, the complications associated with airplane safety have also been brought up as a result, the most concerning of which is terrorism. One of the main counterplans for preventing terrorism is Ground security activities the core of Ground security activities is absolute safety for passengers in both passenger terminal and freight terminal. Subastral security refers to physical protection, proximity control and 100% security search and freight guarding of the passengers' possessions, and the personnel's duties to perform such jobs are be! coming more crucial. On the other hand, Airport security check has bee n gradually developing since the 1960's, when hijacking began to take place. Although the airports have been providing more safe and comfortable services to their customers, terrorism is still happening today. When Ground security activities is minute, the users feel displeasure and discomfort, yet considering solely their convenience can brings problems in achieving safety. Since the 9.11 terror in 2001, the idea of improving and strengthening airport security was reinforced and a considerable amount of estate is being spent today for invention and application of new technology. Various nations, including the United States, have been improving their systems of security through public services; public police department is actively carrying out their duties in airports as well. In San Francisco International Airport, private police department is in charge of collection of data, national events, VIP protection, law enforcement, cooperation within facilities, daily-based patrol and traffic control. Under guidance and supervision of national organizations, such as TSA, general police department interprets X-Rays, operates metal detectors, checks passports or IDs and observes reactions to explosives. Under these circumstances, studies about advancement of cooperation and duties of general police department and private police department necessitated: especially about private police department and their training for searching equipments, decrease in number of turn over rate, invention of technology and prior settlement in estate for security. The privacy of the public, who make up the major population of airport passengers, must also be minimized. In the following research, the activities of police departments in San Francisco International Airport will be analyzed in order to understand recent actions of the United States on airport security.

A Topic Modeling-based Recommender System Considering Changes in User Preferences (고객 선호 변화를 고려한 토픽 모델링 기반 추천 시스템)

  • Kang, So Young;Kim, Jae Kyeong;Choi, Il Young;Kang, Chang Dong
    • Journal of Intelligence and Information Systems
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    • v.26 no.2
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    • pp.43-56
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    • 2020
  • Recommender systems help users make the best choice among various options. Especially, recommender systems play important roles in internet sites as digital information is generated innumerable every second. Many studies on recommender systems have focused on an accurate recommendation. However, there are some problems to overcome in order for the recommendation system to be commercially successful. First, there is a lack of transparency in the recommender system. That is, users cannot know why products are recommended. Second, the recommender system cannot immediately reflect changes in user preferences. That is, although the preference of the user's product changes over time, the recommender system must rebuild the model to reflect the user's preference. Therefore, in this study, we proposed a recommendation methodology using topic modeling and sequential association rule mining to solve these problems from review data. Product reviews provide useful information for recommendations because product reviews include not only rating of the product but also various contents such as user experiences and emotional state. So, reviews imply user preference for the product. So, topic modeling is useful for explaining why items are recommended to users. In addition, sequential association rule mining is useful for identifying changes in user preferences. The proposed methodology is largely divided into two phases. The first phase is to create user profile based on topic modeling. After extracting topics from user reviews on products, user profile on topics is created. The second phase is to recommend products using sequential rules that appear in buying behaviors of users as time passes. The buying behaviors are derived from a change in the topic of each user. A collaborative filtering-based recommendation system was developed as a benchmark system, and we compared the performance of the proposed methodology with that of the collaborative filtering-based recommendation system using Amazon's review dataset. As evaluation metrics, accuracy, recall, precision, and F1 were used. For topic modeling, collapsed Gibbs sampling was conducted. And we extracted 15 topics. Looking at the main topics, topic 1, top 3, topic 4, topic 7, topic 9, topic 13, topic 14 are related to "comedy shows", "high-teen drama series", "crime investigation drama", "horror theme", "British drama", "medical drama", "science fiction drama", respectively. As a result of comparative analysis, the proposed methodology outperformed the collaborative filtering-based recommendation system. From the results, we found that the time just prior to the recommendation was very important for inferring changes in user preference. Therefore, the proposed methodology not only can secure the transparency of the recommender system but also can reflect the user's preferences that change over time. However, the proposed methodology has some limitations. The proposed methodology cannot recommend product elaborately if the number of products included in the topic is large. In addition, the number of sequential patterns is small because the number of topics is too small. Therefore, future research needs to consider these limitations.

Review of Copper Trihydroxychloride, a Green Pigment Composed of Copper and Chlorine (구리와 염소 주성분 녹색 안료 코퍼 트리하이드록시클로라이드(Copper Trihydroxychloride)에 대한 고찰)

  • Oh, Joonsuk;Lee, Saerom;Hwang, Minyoung
    • Korean Journal of Heritage: History & Science
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    • v.53 no.2
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    • pp.64-87
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    • 2020
  • Copper trihydroxychloride (atacamite, botallackite, paratacamite, etc.), the first green pigment used in Mogao Grotto's mural paintings of China, has been known as "copper green", "green salt", and "salt green", etc. and has been used as an important green pigment with malachite. At first, the natural mineral atacamite was employed, but after the Five Dynasties (907~960 CE), synthetic copper trihydroxychloride was primarily used. In Chinese literature, copper green, green salt, and salt green are recorded as being made via reaction with copper powder, Gwangmyeongyeom (natural sodium chloride), and Yosa (natural ammonium chloride), and the prepared material was analyzed to be copper trihydroxychloride. Copper trihydroxychloride pigment was not found in paintings prior to the Joseon Dynasty (1392~1910 CE) in Korea. In analysis of the green pigments used in paintings and the architectural paintworks in the Joseon Dynasty, copper trihydroxychloride was also shown to have been used as an important green pigment with malachite (Seokrok). In particular, the proportion of copper trihydroxychloride use was high in Buddhist paintings, shamanic paintings, and dancheongs (decorative coloring on wooden buildings). Some of these turned out to be synthetic copper trihydroxychloride, but it is unclear whether the rest of them are synthetic or natural pigments due to a lack of analyzed data. From literature and painting analyses, the pigment name of copper trihydroxychloride in the Joseon Dynasty turns out to be Hayeob, a dark green pigment. It is believed to have first been prepared by learning from China in the early Joseon period (early 15th century) and its use continued until the late 19th century with imported Chinese pigment. Round or oval particles with a dark core of copper trihydroxychloride which were used in Chinese literature were similar to the synthetic copper trihydroxychloride pigments used in the Joseon Dynasty and Chinese paintings. Therefore, the synthetic copper trihydroxychloride pigments of Korea and China are believed to have been prepared in a similar way.

Severe Pneumonia Caused by 2009 Pandemic Influenza A (H1N1) Virus in Children and Corticosteroid Treatment (소아에서 2009 신종 인플루엔자 A (H1N1) 중증 폐렴과 스테로이드 치료)

  • Sohn, Yu Rak;Kim, Jong Hee;Ma, Sang Hyuk;Lee, Kyung Yil;Kang, Jin Han
    • Pediatric Infection and Vaccine
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    • v.18 no.2
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    • pp.193-200
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    • 2011
  • Purpose : The effect of corticosteroid on severe pneumonia caused by 2009 pandemic influenza (H1N1) A virus is controversial. This study was aimed to present the effects of early, short-term corticosteroid treatment for severe pneumonia with this virus infection. Methods : A retrospective analysis was performed on severe pneumonia patients (37 patients) who had severe respiratory distress at presentation requiring oxygen therapy and received intravenous methylprednisolone (MP, 8-10 mg/kg, divided in 4 doses/day for 2-3 days) with oseltamivir. The clinical and laboratory characteristics of the patients were evaluated through the medical records and chest radiographic findings. Results : The mean age and male-to-female ratio of the patients were 6.5${\pm}$2.9 years of age, and 3.4:1 (male 29 patients), respectively. The 5-9 aged group was predominant among the age groups (25 patients, 67.6%). Duration of fever prior to admission was 1.4${\pm}$0.6 days and dyspnea developed within 24 h after beginning of respiratory symptoms in all patients. All patients were previously healthy and received oseltamivir within 48 h. Thirteen patients (35.1%) developed dyspnea during oseltamivir treatment. Following MP infusion, all 37 patients including 13 progressive pneumonia patients during oseltamivir treatment showed an immediate halt in the progression of pneumonic infiltration with rapid clinical improvement. There were no side-effects following steroid use. Conclusion : For severe pneumonia patients, early corticosteroid treatment halted clinical exacerbation, and possibly prevented progression to acute respiratory distress syndrome. Further controlled clinical studies are needed for the role of corticosteroids and antivirals on severely affected patients with influenza virus infections.

Buyers' Trust in a Brand and Brand Loyalty in the business-to-business (산업재 시장에서 브랜드 신뢰와 브랜드 충성도에 관한 연구)

  • Han, Sang-Rin;Sung, Hyung-Suk
    • Proceedings of the Korean DIstribution Association Conference
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    • 2005.11a
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    • pp.29-51
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    • 2005
  • Brands are important in the consumer market. They are the interface between consumers and the company, consumers may develop loyalty to brands. also, The late development of industrial marketing explains the near absence of research on Brand Equity in business to business. With recent change, industrial companies have shifted from a production focus to a customer focus. industrial brand is fast developing. The basic purpose of this study is to investigate industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers. Factors hypothesized to influence trust in a brand include a number of brand characteristics, company characteristics and consumer-brand characteristics. This research presented a comprehensive constructive model consisting of components of industrial brand trust and loyalty, and then propose the research model base on prior researches and studies about relationships among components of industrial brand loyalty. Data were gathered from respondents who work in industrial buying center. For this study, Data were analyzed by SPSS 10.0 and AMOS 4.0. The results of this research analysis were as fallow. Industrial brand trust and loyalty were positively related with a number of industrial brand characteristics, supplier characteristics and buyer-brand characteristics. relationship commitment. This research newly proposed the concept of 'industrial brand trust and loyalty affecting the Result of business relationship between industrial buyers and suppliers'

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The Effect of Ex-prisoner's Perception of Stigma on Trust in Interpersonal Relationship (낙인에 대한 출소자의 인식이 대인관계에서 신뢰에 미치는 영향)

  • Gong, Jung Sik
    • Korean Security Journal
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    • no.57
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    • pp.57-84
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    • 2018
  • This study assumes that the perception of the ex-prisoner's against stigma will affect trust in interpersonal relationship. Prior studies have suggested that there is a stigma at the base of the awareness where people avoid and discriminate against ex-prisoner's. This in turn affects ex-prisoner's' recividicism, but there is no study about ex-prisoner's perception of stigma in Korea. Although stigma can be explained in numerous ways, this study is based on the opinion of Phillips(2016), which divides the subscale of stigma as perceived public stigma, perceived personnel stigma, and self stigma. He insisted that ex-prisoner's believe perceived public stigma higher than self-stigma. these results are consistent with this study. However, it is important to note that although ex-prisoner's are more aware of public stigma than self-stigma, they are actually more influenced by self stigma in pereonal relationships. This means that ex-prisoner's are more susceptible to internal psychological awareness than external social recognition. Therefore, the development and intervention of the program to overcome the internal self-stigma of the released prisoner is required. In this study, first, stigma, especially self-stigma turned out to have influence on the interpersonal trust. Therefore, as self-stigma level increased, the interpersonal trust decreased in most cases. Second, it was shown that stigma has the greatest influence on children out of family members, co-workers out of social relationship, self trust out of general relationship in. This confirms that stigma is a factor that greatly influences relationship between important people for ex-prisoner's. Third, since self-sigma negatively reestablish self-identity, make individuals recognize themselves as deviators and show bad lifestyle, which lead them to become habitual offender, ex-prisoner's need to make efforts to overcome self-stigma, and development and intervention of program that can make ex-prisoner's have positive self identity is requested. Fourth, although participants in the study were only male, it seems that there is difference in recognition of stigma by gender, and influence of stigma not only on interpersonal relationships, but also on social reintegration and recidivism imply that these might be good future research topics.