• Title/Summary/Keyword: Status changes

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Predicting the Effects of Rooftop Greening and Evaluating CO2 Sequestration in Urban Heat Island Areas Using Satellite Imagery and Machine Learning (위성영상과 머신러닝 활용 도시열섬 지역 옥상녹화 효과 예측과 이산화탄소 흡수량 평가)

  • Minju Kim;Jeong U Park;Juhyeon Park;Jisoo Park;Chang-Uk Hyun
    • Korean Journal of Remote Sensing
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    • v.39 no.5_1
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    • pp.481-493
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    • 2023
  • In high-density urban areas, the urban heat island effect increases urban temperatures, leading to negative impacts such as worsened air pollution, increased cooling energy consumption, and increased greenhouse gas emissions. In urban environments where it is difficult to secure additional green spaces, rooftop greening is an efficient greenhouse gas reduction strategy. In this study, we not only analyzed the current status of the urban heat island effect but also utilized high-resolution satellite data and spatial information to estimate the available rooftop greening area within the study area. We evaluated the mitigation effect of the urban heat island phenomenon and carbon sequestration capacity through temperature predictions resulting from rooftop greening. To achieve this, we utilized WorldView-2 satellite data to classify land cover in the urban heat island areas of Busan city. We developed a prediction model for temperature changes before and after rooftop greening using machine learning techniques. To assess the degree of urban heat island mitigation due to changes in rooftop greening areas, we constructed a temperature change prediction model with temperature as the dependent variable using the random forest technique. In this process, we built a multiple regression model to derive high-resolution land surface temperatures for training data using Google Earth Engine, combining Landsat-8 and Sentinel-2 satellite data. Additionally, we evaluated carbon sequestration based on rooftop greening areas using a carbon absorption capacity per plant. The results of this study suggest that the developed satellite-based urban heat island assessment and temperature change prediction technology using Random Forest models can be applied to urban heat island-vulnerable areas with potential for expansion.

A Comparative Study on the Ginseng Consumption Culture of College Consumers in Korea and China - Focused on Attitudes Toward Ginseng and Intention to Purchase it - (한국과 중국 소비자의 인삼 소비문화 비교 연구 -대학생 소비자의 인삼에 대한 태도와 구매 의도를 중심으로)

  • Siwuel Kim
    • Journal of Ginseng Culture
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    • v.6
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    • pp.135-151
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    • 2024
  • In order to compare the ginseng consumption culture of Korean and Chinese college students, their purchase status of ginseng products, attitudes toward ginseng, and satisfaction with ginseng products were examined, and the purchase and recommendation intention of ginseng products was investigated. It targeted 267 Korean college students and 318 Chinese college students who had experience eating ginseng products. As a result of the survey, in the case of Korean college student consumers, interest in ginseng products increased compared to before COVID-19, and the intention to purchase and recommend ginseng products increased. In addition, the higher the satisfaction with ginseng, the higher the frequency of ginseng purchase experience, the higher the social benefit attitude toward ginseng, and the higher the age, the higher the intention to purchase and recommend ginseng products. Chinese college student consumers had higher parental purchases than Korea, higher positive intentions to purchase and recommend social and psychological benefits, and their 20s are already more interested and friendly than Korea. What Korean college students and Chinese college student consumers have in common is that interest in health, safety, and environment has increased since before COVID-19, and interest in ginseng-related products has changed in individual experiences, indicating that individual experiences are important and Chinese college student consumers are influenced by parents. In particular, COVID-19 is an opportunity to recognize the importance of health, which is important to those in their 20s, and is actually related to purchase intention. Focusing on these results, it seems that expansion to preferred products for college student consumers and differentiation of marketing strategies according to family influence and consumption culture should be made, and these new changes due to COVID-19 seem to be a timely opportunity. At a time when interest in health and safety has increased, strategic preparations are needed for the future consumersociety to respond to changesin product diversity and convergence, changes in marketing media to meet consumer consumption values, and changesin consumer family types, such assingle households.

MR T2 Map Technique: How to Assess Changes in Cartilage of Patients with Osteoarthritis of the Knee (MR T2 Map 기법을 이용한 슬관절염 환자의 연골 변화 평가)

  • Cho, Jae-Hwan;Park, Cheol-Soo;Lee, Sun-Yeob;Kim, Bo-Hui
    • Progress in Medical Physics
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    • v.20 no.4
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    • pp.298-307
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    • 2009
  • By using the MR T2 map technique, this study intends, first, to measure the change of T2 values of cartilage between healthy people and patients with osteoarthritis and, second, to assess the form and the damage of cartilage in the knee-joint, through which this study would consider the utility of the T2 map technique. Thirty healthy people were selected based on their clinical history and current status and another thirty patients with osteoarthritis of the knee who were screened by simple X-ray from November 2007 to December 2008 were selected. Their T2 Spin Echo (SE hereafter) images for the cartilage of the knee joint were collected by using the T2 SE sequence, one of the multi-echo methods (TR: 1,000 ms; TE values: 6.5, 13, 19.5, 26, 32.5. 40, 45.5, 52). Based on these images, the changes in the signal intensity (SI hereafter) for each section of the cartilage of the knee joint were measured, which yielded average values of T2 through the Origin 7.0 Professional (Northampton, MA 01060 USA). With these T2s, the independent samples T-test was performed by SPSS Window version 12.0 to run the quantitative analysis and to test the statistical significance between the healthy group and the patient group. Closely looking at T2 values for each anterior and lateral articular cartilage of the sagittal plane and the coronal plane, in the sagittal plane, the average T2 of the femoral cartilage in the patient group with arthritis of the knee ($42.22{\pm}2.91$) was higher than the average T2 of the healthy group ($36.26{\pm}5.01$). Also, the average T2 of the tibial cartilage in the patient group ($43.83{\pm}1.43$) was higher than the average T2 in the healthy group ($36.45{\pm}3.15$). In the case of the coronal plane, the average T2 of the medial femoral cartilage in the patient group ($45.65{\pm}7.10$) was higher than the healthy group ($36.49{\pm}8.41$) and so did the average T2 of the anterior tibial cartilage (i.e., $44.46{\pm}3.44$ for the patient group vs. $37.61{\pm}1.97$ for the healthy group). As for the lateral femoral cartilage in the coronal plane, the patient group displayed the higher T2 ($43.41{\pm}4.99$) than the healthy group did ($37.64{\pm}4.02$) and this tendency was similar in the lateral tibial cartilage (i.e., $43.78{\pm}8.08$ for the patient group vs. $36.62{\pm}7.81$ for the healthy group). Along with the morphological MR imaging technique previously used, the T2 map technique seems to help patients with cartilage problems, in particular, those with the arthritis of the knee for early diagnosis by quantitatively analyzing the structural and functional changes of the cartilage.

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Mobility Change around Neighborhood Parks and Green Spaces before and after the Outbreak of the COVID-19 Pandemic (COVID-19 발생 전·후 생활권 공원녹지 모빌리티 변화 분석)

  • Choi, Ga yoon;Kim, Yong gook;Kwon, Oh kyu;Yoo, Ye seul
    • Journal of the Korean Institute of Landscape Architecture
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    • v.51 no.4
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    • pp.101-118
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    • 2023
  • During the COVID-19 pandemic, the utilization rate of neighborhood parks and green spaces increased significantly, and the outbreak served as an opportunity to highlight the values and functions of neighborhood parks and green spaces for urban residents. This study aims to empirically analyze how citizens' movement and the use of neighborhood parks and green spaces changed before and after COVID-19 and examine the social and spatial characteristics that affected these changes. As a research method, first, people's mobility around neighborhood parks and green spaces before and after the COVID-19 pandemic were compared using signal data from telecommunication carriers. Through the analysis of changes in residence time and movement volume, the movement characteristics of citizens after COVID-19 and changes in walking-based park visits were examined. Second, the factors affecting the mobility change in neighborhood parks and green spaces were analyzed. The social and spatial characteristics that affect citizens' visits to neighborhood parks and green spaces before and after COVID-19 were examined through correlation and multiple regression analysis. Subsequently, through cluster analysis, the types of living areas for the post-COVID era were classified from the perspective of the supply and management of neighborhood parks and green spaces services, and directions for improving neighborhood parks and green spaces by type were presented. Major research findings are as follows: First, since the outbreak of COVID-19, activities within 500m of the residence have increased. The amount of stay and walking movement increased in both 2020 and 2021, which means that the need to review the quantitative standards and attractions of neighborhood parks and green spaces has increased considering the changed scope of the walking and living area. Second, the overall number of visits to neighborhood parks and green spaces by walking has increased since the outbreak of COVID-19. The number of visits to neighborhood parks and green spaces centered on the house and the workplace increased significantly. The park green policy in the post-COVID era should be promoted by discovering underprivileged areas, focusing on areas where residential, commercial, and business facilities are concentrated, and improving neighborhood parks and green services in quantitative and qualitative terms. Third, it was found that the higher the level of park green service, the higher the amount of walking movement. It is necessary to use indicators that contribute to improving citizens' actual park green services, such as walking accessibility, rather than looking at the criteria for securing green areas. Fourth, as a result of cluster analysis, five types of neighborhood parks and green spaces were derived in response to the post-COVID era. This suggests that it is necessary to consider the socioeconomic status and characteristics of living areas and the level of park green services required in future park green policies. This study has academic and policy significance in that it has laid the basis for establishing neighborhood parks and green spaces policy in response to the post-COVID era by using various analysis methodologies such as carrier signal data analysis, GIS analysis, and statistical analysis.

Optimum Management Plan for Soil Contamination Facilities (특정토양오염관리대상시설의 최적 관리방안에 관한 연구)

  • Park, Jae-Soo;Kim, Ki-Ho;Kim, Hae-Keum;Choi, Sang-Il
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.2
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    • pp.293-300
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    • 2012
  • This study was to investigate the unsuitable rate of the storage facilities, the changes in corrosion process over time after installation according to the status, the time to install the facilities, years elapsed after facilities installation, inspection of methods and motivation, and so on, based on the results of the inspection at the petroleum storage facilities conducted by domestic soil-relate specialized agency to derive optimal management plans which meet the status of soil contamination facilities. The results showed that the facilities more than 5 years after the initial leak test at the time of the installation need to be inspected periodically by considering costs of leak test and remediation of polluted soil. The inspection period can be decided by cost and leak test methods showing discrepancies for the results obtained from individual test whether it was direct or indirect. To compensate these matters, we suggested that the direct inspection method on regular schedule is recommended. On the other hand, the inspection can be voluntarily completed to ease burden of the results by inspection or equivalent level to this inspection method. Also, it may need improved construction supervision and performance test system to minimize the occurrence of the nature defects in installing the facilities as well as the upgrade program for the facilities during intervals of inspection period.

A Study on the Observation of Soil Moisture Conditions and its Applied Possibility in Agriculture Using Land Surface Temperature and NDVI from Landsat-8 OLI/TIRS Satellite Image (Landsat-8 OLI/TIRS 위성영상의 지표온도와 식생지수를 이용한 토양의 수분 상태 관측 및 농업분야에의 응용 가능성 연구)

  • Chae, Sung-Ho;Park, Sung-Hwan;Lee, Moung-Jin
    • Korean Journal of Remote Sensing
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    • v.33 no.6_1
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    • pp.931-946
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    • 2017
  • The purpose of this study is to observe and analyze soil moisture conditions with high resolution and to evaluate its application feasibility to agriculture. For this purpose, we used three Landsat-8 OLI (Operational Land Imager)/TIRS (Thermal Infrared Sensor) optical and thermal infrared satellite images taken from May to June 2015, 2016, and 2017, including the rural areas of Jeollabuk-do, where 46% of agricultural areas are located. The soil moisture conditions at each date in the study area can be effectively obtained through the SPI (Standardized Precipitation Index)3 drought index, and each image has near normal, moderately wet, and moderately dry soil moisture conditions. The temperature vegetation dryness index (TVDI) was calculated to observe the soil moisture status from the Landsat-8 OLI/TIRS images with different soil moisture conditions and to compare and analyze the soil moisture conditions obtained from the SPI3 drought index. TVDI is estimated from the relationship between LST (Land Surface Temperature) and NDVI (Normalized Difference Vegetation Index) calculated from Landsat-8 OLI/TIRS satellite images. The maximum/minimum values of LST according to NDVI are extracted from the distribution of pixels in the feature space of LST-NDVI, and the Dry/Wet edges of LST according to NDVI can be determined by linear regression analysis. The TVDI value is obtained by calculating the ratio of the LST value between the two edges. We classified the relative soil moisture conditions from the TVDI values into five stages: very wet, wet, normal, dry, and very dry and compared to the soil moisture conditions obtained from SPI3. Due to the rice-planing season from May to June, 62% of the whole images were classified as wet and very wet due to paddy field areas which are the largest proportions in the image. Also, the pixels classified as normal were analyzed because of the influence of the field area in the image. The TVDI classification results for the whole image roughly corresponded to the SPI3 soil moisture condition, but they did not correspond to the subdivision results which are very dry, wet, and very wet. In addition, after extracting and classifying agricultural areas of paddy field and field, the paddy field area did not correspond to the SPI3 drought index in the very dry, normal and very wet classification results, and the field area did not correspond to the SPI3 drought index in the normal classification. This is considered to be a problem in Dry/Wet edge estimation due to outlier such as extremely dry bare soil and very wet paddy field area, water, cloud and mountain topography effects (shadow). However, in the agricultural area, especially the field area, in May to June, it was possible to effectively observe the soil moisture conditions as a subdivision. It is expected that the application of this method will be possible by observing the temporal and spatial changes of the soil moisture status in the agricultural area using the optical satellite with high spatial resolution and forecasting the agricultural production.

The Photography as Technological Aesthetics (데크놀로지 미학으로서의 사진)

  • Jin, Dong-Sun
    • Journal of Science of Art and Design
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    • v.11
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    • pp.221-249
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    • 2007
  • Today, photography is facing to the crisis of identity and dilemma of ontology from the digital imaging process in the new technology form. It is very important points to say rethinking of the traditional photographic medium, that has changed the way we view the world and ourselves is perhaps an understatement and that photography has transformed our essential understanding of reality. Now, no longer are photographic images regarded as the true automatic recording, innocent evidence and the mirror to the reality. Rather, photography constructs the world for our entertainment, helping to create the comforting illusions by which we live. The recognition that photographs are not constructions and reflections of reality, is the basis for the actual presence within the contemporary photographic world. It is shock. This thesis's aim is to look for the problems of photographic identity and ontological crisis that is controlling and regulating digital photographic imagery, allowing the reproduction of the electronic simulations era. Photography loses its special aesthetic status and becomes no more true information and, exclusively evidence by traditional film and paper that appeared both as a technological accuracy and as a medium-specific aesthetic. The result, photography is facing two crises, one is the photographic ontology(the introduction of computerized digital images) and the other is photographic epistemology(having to do broader changes in ethics, knowledge and culture). Taken together, these crises apparently threaten us with the death of photography, with the 'end' of photography and the culture it sustains. The thesis's meaning is to look into the dilemma of photography's ontology and epistemology, especially, automatical index and digital codes from its origin, meaning, and identity as the technological medium. Thus, in particular, thesis focuses on the analog imagery presence, from the nature in the material world, and the digital imagery presence from the cultural situations in our society. And also thesis's aim is to examine the main issues of the history of photography has been concentrated on the ontological arguments since the discovery of photography in 1839. Photography has never been only one static technology form. Rather, its nearly two centuries of technological development have been marked by numerous, competing of technological innovation and self revolution from the dual aspects. This thesis examines recent account of photography by the analysis of the medium's concept, meaning, identity between film base image and digital base image from the aspects of photographic ontology and epistemology. Thus, the structure of thesis is fairy straightforward to examine what appear to be two opposing view of photographic conditions and ontological situations. Thesis' view contrasts that figure out the value of photography according to its fundamental characteristic as a medium. Also, it seeks a possible solution to the dilemma of photographic ontology through the medium's origin from the early years of the nineteenth century to the raising questions about the different meaning(analog/digital) of photography, now. Finally, this thesis emphasizes and concludes that the photographic ontological crisis reflects to the paradoxical dynamic structure, that unsolved the origins of the medium, itself. Moreover, even photography is not single identity of the photographic ontology, and also can not be understood as having a static identity or singular status from the dynamic field of technologies, practices, and images.

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A Study on the Curriculum for Record Management Science Education - with focus on the Faculty of Cultural Information Resources, Surugadai University; Evolving Program, New Connections (기록관리학의 발전을 위한 교육과정연구 -준하태(駿河台)(스루가다이)대학(大學)의 경우를 중심(中心)으로-)

  • Kim, Yong-Won
    • Journal of Korean Society of Archives and Records Management
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    • v.1 no.1
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    • pp.69-94
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    • 2001
  • The purpose of this paper is to provide an overview of the current status of the records management science education in Japan, and to examine the implications of the rapid growth of this filed while noting some of its significant issues and problems. The goal of records management science education is to improve the quality of information services and to assure an adequate supply of information professionals. Because records management science programs prepare students for a professional career, their curricula must encompass elements of both education and practical training. This is often expressed as a contrast between theory and practice. The confluence of the social, economic and technological realities of the environment where the learning takes place affects both. This paper reviews the historical background and current trends of records management science education in Japan. It also analyzes the various types of curriculum and the teaching staff of these institutions, with focus on the status of the undergraduate program at Surugadai University, the first comprehensive, university level program in Japan. The Faculty of Cultural Information Resources, Surugadai University, a new school toward an integrated information disciplines, was opened in 1994, to explore the theory and practice of the management diverse cultural information resources. Its purpose was to stimulate and promote research in additional fields of information science by offering professional training in archival science, records management, and museum curatorship, as well as librarianship. In 1999, the school introduced a master program, the first in Japan. The Faculty has two departments and each of them has two courses; Department of Sensory Information Resources Management; -Sound and Audiovisual Information Management, -Landscape and Tourism Information Management, Department of Knowledge Information Resources Management; -Library and Information Management, -Records and Archives Management The structure of the entire curriculum is also organized in stages from the time of entrance through basic instruction and onwards. Orientation subjects which a student takes immediately upon entering university is an introduction to specialized education, in which he learns the basic methods of university education and study, During his first and second years, he arranges Basic and Core courses as essential steps towards specialization at university. For this purpose, the courses offer a wide variety of study topics. The number of courses offered, including these, amounts to approximately 150. While from his third year onwards, he begins specific courses that apply to his major field, and in a gradual accumulation of seminar classes and practical training, puts his knowledge grained to practical use. Courses pertaining to these departments are offered to students beginning their second year. However, there is no impenetrable wall between the two departments, and there are only minor differences with regard requirements for graduation. Students may select third or fourth year seminars regardless of the department to which they belong. To be awarded a B.A. in Cultural Information Resources, the student is required to earn 34 credits in Basic Courses(such as, Social History of Cultural Information, Cultural Anthropology, History of Science, Behavioral Sciences, Communication, etc.), 16 credits in Foreign Languages(including 10 in English), 14 credits on Information Processing(including both theory and practice), and 60 credits in the courses for his or her major. Finally, several of the issues and problems currently facing records management science education in Japan are briefly summarized below; -Integration and Incorporation of related areas and similar programs, -Curriculum Improvement, -Insufficient of Textbooks, -Lack of qualified Teachers, -Problems of the employment of Graduates. As we moved toward more sophisticated, integrated, multimedia information services, information professionals will need to work more closely with colleagues in other specialties. It will become essential to the survival of the information professions for librarians to work with archivists, record managers and museum curators. Managing the changes in our increasingly information-intensive society demands strong coalitions among everyone in cultural Institutions. To provide our future colleagues with these competencies will require building and strengthening partnerships within and across the information professions and across national borders.

Review of Sexual Dysfunction in Male Schizophrenics (남자 정신분열병 환자에서 성기능장애에 대한 검토)

  • Choi, Yeong Tae;Cheon, Jin Sook;Oh, Byoung Hoon
    • Korean Journal of Biological Psychiatry
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    • v.7 no.1
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    • pp.85-98
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    • 2000
  • Objective : There are four possible explanations for the sexual dysfunction of schizophrenics. The first is the possibility of a real structural aspect. The second possibility is that sexual function changes secondary to the illness. The third possibility is that there are medical and sociocultural barriers to sexual expression for chronic schizophrenics. The fourth possibility is that sexual dysfunction due to antipsychotic medication. However, we didn't know the precise cause of sexual dysfunction in schizophrenics. Therefore, the purpose of this study was to explore the mechanism of illness itself and antipsychotics on sexual dysfunction in male schizophrenics. Methods : The serum prolactin(PRL), testosterone(TST), and the plasma serotonin(5-HT) concentrations were measured by radioimmunoassay and high performance liquid chromatography method for 100 healthy male schizophrenics according to the DSM-IV. Concomitantly, the severity of psychotic symptoms using Clinical Global Impression(CGI), Brief Psychiatric Rating Scale(BPRS), Positive and Negative Syndrome Scale(PANSS), and the severity of side effects for antipsychotics using Extrapyramidal Side Effects Scale(EPSE), Anticholinergic Side Effects Scale(ACSE), the cognitive function using PANSS-Cognitive Function(PANSS-CF), Mini Mental State Exam-Korean(MMSE-K), and the sexual dysfunction using Sexual Functioning Questionnaire(SFQ), Questionnaire for Sexual Dysfunction in Men were assessed. The PRL, TST, and 5-HT levels of 50 healthy male controls who had no medical, neurological, and psychiatric illnesses were evaluated. The sexual function using SFQ(items FGa, FNa) were also assessed. Furthermore, the correlation with age, education, religion, economic status, age at onset, duration of illnesses, duration of admission, levels of PRL, TST, 5-HT, antipsychotic dosages, potency, benztropine, total duration of medication, EPSE, ACSE, CGI, BPRS, PANSS, PANSS-CF, MMSE-K and sexual dysfunctions were identified in male schizophrenics. Results : 1) The frequencies of sexual dysfunctions for schizophrenics(80%) were significantly(p<0.001) higher than those for controls(42%). The sexual dysfunctions according to sexual response cycle were 'low sexual desire' 76%, 'impairment of achieving erection' 75%, 'impairment of maintaining erection' 75%, 'impairment of obtaining orgasm' 32%, 'impairment in the quality of orgasm' 61%, 'impairment in quantity of ejaculate' 44%, 'premature ejaculation' 15%, and 'delayed ejaculation' 50%. 2) The PRL, 5-HT levels of schizophrenics($28.5{\pm}20.6ng/ml$, $298.5{\pm}89.1ng/ml$) were significantly(p<0.001) higher than those of controls($10{\pm}5.6ng/ml$, $169.2{\pm}37.8ng/ml$), while the TST levels of schizophrenics($4.3{\pm}1.5ng/ml$) and controls($4.5{\pm}1.2ng/ml$) were not significantly different. The sexual dysfunctions of schizophrenics who had abnormal 5-HT levels($4.7{\pm}1.3$ scores) were significantly(p<0.05) higher than those of who had normal 5-HT levels($3.8{\pm}1.6$ scores) on item D7. 3) The sexual dysfunctions of unmarried schizophrenics were significantly(p<0.01 : p<0.05) higher than those of married schizophrenics($6.1{\pm}2.8$ scores, $4.7{\pm}1.3$ scores on item FGa : ${\beta}$=-0.211 on item FNa). The sexual dysfunctions were positively correlated with the rise of 5-HT levels(r=0.209, p<0.05 on item D4 and r=0.241, p<0.05 on item D7), the higher age at onset(r=0.275, p<0.01 on item FNa : r=-0.202, p<0.05 on item FDa), the longer duration of illnesses(r=0.237, p<0.05 on item D6), the longer duration of admission(r=0.234, p<0.05 on item D4 : r=0.328, p<0.05 on item D6), the longer total duration of medication(r=0.237, p<0.05 on item D6). However, age, education, religion, economic status, PRL, TST levels, antipsychotics dosage, potency, benztropine, ACSE, CGI, BPRS, PANSS, PANSS-CF, MMSE-K scores were not correlated with increased sexual dysfunctions. Conclusions : Male schizophrenics have significantly more sexual dysfunction to compare with controls. The higher frequencies of sexual dysfunctions were low sexual desire and erectile disorder. The unmarried, higher age at onset, and longer duration of diseases were positively correlated with increased sexual dysfunctions. Also high 5-HT levels were positively correlated with increased sexual dysfunctions. This means that studies of plasma 5-HT levels, albeit questionable indicators of central 5-HT function, offer some additional support for the association of sexual dysfunction with excess 5-HT activity as primary pathology of schizophrenia. Our findings suggest that excess 5-HT activity seems to affect the patient's sexual function.

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Effect of Ketanserin and Positive End Expiratory Pressure Ventilation on Hemodynamics and Gas Exchange in Experimental Acute Pulmonary Embolism (실험적 급성 폐동맥색전증에서 Ketanserin과 Positive End Expiratory Pressure Ventilation이 혈류역학 및 환기에 미치는 영향)

  • Lee, Sang-Do;Lee, Young-Hyun;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.2
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    • pp.135-146
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    • 1993
  • Background: In acute pulmonary embolism it has been postulated that the constriction of bronchi and pulmonary artery secondary to neurohumoral response plays an important role in cardiopulmonary dysfunction in addition to the mechanical obstruction of pulmonary artery. Serotonin is considered as the most important mediator. Positive end expiratory pressure (PEEP) stimulates $PGI_2$ secretion from the vascular endothelium, but its role in acute pulmonary embolism is still in controversy. Methods: To study the cardiopulmonary effect and therapeutic role of Ketanserin, selective antagonist of 5-HT2 receptor, and PEEP in acute pulmonary embolism experimental acute pulmonary embolism was induced in dogs with autologous blood clot. The experimental animals were divided into 3 groups, that is control group, Ketanserin injection group and PEEP application group. Results: Thirty minutes after embolization, mean pulmonary arterial pressure and pulmonary vascular resistance increased and cardiac output decreased. $PaO_2,\;P\bar{v}O_2$ and oxygen transport decreased and physiological shunt and $PaCO_2$ increased. After injection of Ketanserin, comparing with control group, mean pulmonary arterial pressure, pulmonary vascular resistance and physiological shunt decreased, while cardiac output, $PaO_2$ and oxygen transport increased. All these changes sustained till 4 hours after embolization. After PEEP application pulmonary vascular resistance, $PaO_2$ and $PaCO_2$ increased, while physiological shunt, cardiac output and oxygen transport decreased. After discontinuation of PEEP, mean pulmonary arterial pressure and pulmonary vascular resistance decreased and were lower than control group, while $PaO_2$ and cardiac output increased and higher than control group. $PaCO_2$ decreased but showed no significant difference comparing with control group. Conclusion: It can be concluded that Ketanserin is effective for the treatment of acute pulmonary embolism. With PEEP hemodynamic status deteriorated, but improved better than control group after discontinuation of PEEP. Thus PEEP may be applied carefully for short period in acute pulmonary embolism if the hemodynamic status is tolerable.

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