• Journal of Intelligence and Information Systems
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• v.23 no.2
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• pp.107-122
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• 2017

Volatility in the stock market returns is a measure of investment risk. It plays a central role in portfolio optimization, asset pricing and risk management as well as most theoretical financial models. Engle(1982) presented a pioneering paper on the stock market volatility that explains the time-variant characteristics embedded in the stock market return volatility. His model, Autoregressive Conditional Heteroscedasticity (ARCH), was generalized by Bollerslev(1986) as GARCH models. Empirical studies have shown that GARCH models describes well the fat-tailed return distributions and volatility clustering phenomenon appearing in stock prices. The parameters of the GARCH models are generally estimated by the maximum likelihood estimation (MLE) based on the standard normal density. But, since 1987 Black Monday, the stock market prices have become very complex and shown a lot of noisy terms. Recent studies start to apply artificial intelligent approach in estimating the GARCH parameters as a substitute for the MLE. The paper presents SVR-based GARCH process and compares with MLE-based GARCH process to estimate the parameters of GARCH models which are known to well forecast stock market volatility. Kernel functions used in SVR estimation process are linear, polynomial and radial. We analyzed the suggested models with KOSPI 200 Index. This index is constituted by 200 blue chip stocks listed in the Korea Exchange. We sampled KOSPI 200 daily closing values from 2010 to 2015. Sample observations are 1487 days. We used 1187 days to train the suggested GARCH models and the remaining 300 days were used as testing data. First, symmetric and asymmetric GARCH models are estimated by MLE. We forecasted KOSPI 200 Index return volatility and the statistical metric MSE shows better results for the asymmetric GARCH models such as E-GARCH or GJR-GARCH. This is consistent with the documented non-normal return distribution characteristics with fat-tail and leptokurtosis. Compared with MLE estimation process, SVR-based GARCH models outperform the MLE methodology in KOSPI 200 Index return volatility forecasting. Polynomial kernel function shows exceptionally lower forecasting accuracy. We suggested Intelligent Volatility Trading System (IVTS) that utilizes the forecasted volatility results. IVTS entry rules are as follows. If forecasted tomorrow volatility will increase then buy volatility today. If forecasted tomorrow volatility will decrease then sell volatility today. If forecasted volatility direction does not change we hold the existing buy or sell positions. IVTS is assumed to buy and sell historical volatility values. This is somewhat unreal because we cannot trade historical volatility values themselves. But our simulation results are meaningful since the Korea Exchange introduced volatility futures contract that traders can trade since November 2014. The trading systems with SVR-based GARCH models show higher returns than MLE-based GARCH in the testing period. And trading profitable percentages of MLE-based GARCH IVTS models range from 47.5% to 50.0%, trading profitable percentages of SVR-based GARCH IVTS models range from 51.8% to 59.7%. MLE-based symmetric S-GARCH shows +150.2% return and SVR-based symmetric S-GARCH shows +526.4% return. MLE-based asymmetric E-GARCH shows -72% return and SVR-based asymmetric E-GARCH shows +245.6% return. MLE-based asymmetric GJR-GARCH shows -98.7% return and SVR-based asymmetric GJR-GARCH shows +126.3% return. Linear kernel function shows higher trading returns than radial kernel function. Best performance of SVR-based IVTS is +526.4% and that of MLE-based IVTS is +150.2%. SVR-based GARCH IVTS shows higher trading frequency. This study has some limitations. Our models are solely based on SVR. Other artificial intelligence models are needed to search for better performance. We do not consider costs incurred in the trading process including brokerage commissions and slippage costs. IVTS trading performance is unreal since we use historical volatility values as trading objects. The exact forecasting of stock market volatility is essential in the real trading as well as asset pricing models. Further studies on other machine learning-based GARCH models can give better information for the stock market investors.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.5
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• pp.335-347
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• 2013

In February 2008, high storm waves due to a developed atmospheric low pressure system propagating from the west off Hokkaido, Japan, to the south and southwest throughout the East Sea (ES) caused extensive damages along the central coast of Japan and along the east coast of Korea. This study consists of two parts. In the first part, we estimate extreme storm wave characteristics in the Toyama Bay where heavy coastal damages occurred, using a non-hydrostatic meteorological model and a spectral wave model by considering the extreme conditions for two factors for wind wave growth, such as wind intensity and duration. The estimated extreme significant wave height and corresponding wave period were 6.78 m and 18.28 sec, respectively, at the Fushiki Toyama. In the second part, we perform numerical experiments on wave-structure interaction in the Fushiki Port, Toyama Bay, where the long North-Breakwater was heavily damaged by the storm waves in February 2008. The experiments are conducted using a non-linear shallow-water equation model with adaptive mesh refinement (AMR) and wet-dry scheme. The estimated extreme storm waves of 6.78 m and 18.28 sec are used for incident wave profile. The results show that the Fushiki Port would be overtopped and flooded by extreme storm waves if the North-Breakwater does not function properly after being damaged. Also the storm waves would overtop seawalls and sidewalls of the Manyou Pier behind the North-Breakwater. The results also depict that refined meshes by AMR method with wet-dry scheme applied capture the coastline and coastal structure well while keeping the computational load efficiently.

• Journal of Korean Academy of Nursing
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• v.19 no.2
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• pp.212-222
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• 1989

When the head nurse who is pivotal in the nursing service administration of the hospital performs efficiently as a first-line manager, the effectiveness of the nursing unit, which includes the quality of nursing care, the jab satisfaction of staff members, and the cohesiveness of staff members is increased. With this point of view in mind, the researcher carried out a study to determine the actual work (the content of the work, the work process, the role of the head nurse, the activity media, and the purpose of the work) of the head nurse in a university hospital in Korea. In addition, this study was also carried out for the purpose of preparing an ideal model for the work of the head nurse. The research subjects were 39 head nurses. This included all the head nurses in two university hospitals except those who were working in outpatient care, operating rooms, central supply, nursing administration, in-service education and emergency care. Data were collected from September 24th to October 21th, 1987 and April 4th to 12th, 1988. A work activity record on which the head nurse recorded directly in a chronological narrative form, was used as the research instrument. The 234 work activity records, 39 head nurse's continuous recording over 6 days(from Monday to Saturday) were collected and analysed. The results were as follows ; 1. With regard to the work content for the total daily work of the head nurse, 45.2% of the activities were managerial activities but 58.1% of the head nurse' s time was spent in direct patient care. 2. With regard to the work process of the head nurse, specifically the location, the size and membership of groups contacted, the results were as follows : 1) Of the total daily work activities 92.4% were carried out in the nursing unit and this occupied 84.5% of total daily work time. Direct patient care was generally performed on the nursing unit and managerial work was performed in other areas. 2) Of the total daily work activities, 73% was with one or more persons and 51.2% of total daily work time was spent in groups. 3) A total of 51 persons, working in different capacities were contacted. These included 21 persons giving patient care, 19 persons working in nursing unit management, and 7 persons working in human resource management. 3. With regard to the head nurse's role in work activity, 53.3% of total daily work activities involved the informational role, 26.9%, the interpersonal role and 19.9%, the decisional role. With regard to time, 57.7% was spent in the informational role, 23.9%, in the interpersonal role and 18.3%, in the decisional role. When the head nurse performed managerial work, she gave nearly equal emphasis to all three roles when she gave direct patient care the informational role was increased. 4. With regard to the activity media, the number of unscheduled activities accounted for 27.1% of the activities, scheduled activities, 24.3%, desk work activity, 22.1%, rounds, 12.5% and telephone calls, made or received, 14.0%. In daily total work time managerial work related to desk work and scheduled activities were high, ranging from 29.8% to 29.9% but for direct patient care time, scheduled activities and unscheduled activities were high, ranging from 23.6％ to 35.3%. 5. With regard to the purpose of the work performed, 54.4% of the total daily work was concerned with the team and 41.4% was concerned with the agency. The managerial work was concerned mainly with the team and the direct patient care was concerned mainly with the patient. When the frequency of an activity and time were compared no significant difference was found between the days for which the work was recorded for any of the variables : the work content, the work process, the work role, the activity media and purpose of the work. On the basis of this study the following are proposed as an ideal model for head nurse work in Korea : The managerial work should be increased to 70%. The decisional role activities should be increased to 40%. Twenty percent of the work activity should be allocated to agency, community and profession. It is believed that this model for the head nurse's work can contribute to guidelines for job description development. Finally, educational programs, organizational and structural devices, and administrative support are needed for the proper function of the head nurse in this proposed model.

• Asia pacific journal of information systems
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• v.24 no.2
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• pp.191-210
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• 2014

As mobile devices that can be connected to the Internet have spread and networking has become possible whenever/wherever, the Internet has become central in the dissemination and consumption of news. Accordingly, the ways news is gathered, disseminated, and consumed have changed greatly. In the traditional news media such as magazines and newspapers, expert editors determined what events were worthy of deploying their staffs or freelancers to cover and what stories from newswires or other sources would be printed. Furthermore, they determined how these stories would be displayed in their publications in terms of page placement, space allocation, type sizes, photographs, and other graphic elements. In turn, readers-news consumers-judged the importance of news not only by its subject and content, but also through subsidiary information such as its location and how it was displayed. Their judgments reflected their acceptance of an assumption that these expert editors had the knowledge and ability not only to serve as gatekeepers in determining what news was valuable and important but also how to rank its value and importance. As such, news assembled, dispensed, and consumed in this manner can be said to be expert-based recommended news. However, in the era of Internet news, the role of expert editors as gatekeepers has been greatly diminished. Many Internet news sites offer a huge volume of news on diverse topics from many media companies, thereby eliminating in many cases the gatekeeper role of expert editors. One result has been to turn news users from passive receptacles into activists who search for news that reflects their interests or tastes. To solve the problem of an overload of information and enhance the efficiency of news users' searches, Internet news sites have introduced numerous recommendation techniques. Recommendations based on popularity constitute one of the most frequently used of these techniques. This popularity-based approach shows a list of those news items that have been read and shared by many people, based on users' behavior such as clicks, evaluations, and sharing. "most-viewed list," "most-replied list," and "real-time issue" found on news sites belong to this system. Given that collective intelligence serves as the premise of these popularity-based recommendations, popularity-based news recommendations would be considered highly important because stories that have been read and shared by many people are presumably more likely to be better than those preferred by only a few people. However, these recommendations may reflect a popularity bias because stories judged likely to be more popular have been placed where they will be most noticeable. As a result, such stories are more likely to be continuously exposed and included in popularity-based recommended news lists. Popular news stories cannot be said to be necessarily those that are most important to readers. Given that many people use popularity-based recommended news and that the popularity-based recommendation approach greatly affects patterns of news use, a review of whether popularity-based news recommendations actually reflect important news can be said to be an indispensable procedure. Therefore, in this study, popularity-based news recommendations of an Internet news portal was compared with top placements of news in printed newspapers, and news users' judgments of which stories were personally and socially important were analyzed. The study was conducted in two stages. In the first stage, content analyses were used to compare the content of the popularity-based news recommendations of an Internet news site with those of the expert-based news recommendations of printed newspapers. Five days of news stories were collected. "most-viewed list" of the Naver portal site were used as the popularity-based recommendations; the expert-based recommendations were represented by the top pieces of news from five major daily newspapers-the Chosun Ilbo, the JoongAng Ilbo, the Dong-A Daily News, the Hankyoreh Shinmun, and the Kyunghyang Shinmun. In the second stage, along with the news stories collected in the first stage, some Internet news stories and some news stories from printed newspapers that the Internet and the newspapers did not have in common were randomly extracted and used in online questionnaire surveys that asked the importance of these selected news stories. According to our analysis, only 10.81% of the popularity-based news recommendations were similar in content with the expert-based news judgments. Therefore, the content of popularity-based news recommendations appears to be quite different from the content of expert-based recommendations. The differences in importance between these two groups of news stories were analyzed, and the results indicated that whereas the two groups did not differ significantly in their recommendations of stories of personal importance, the expert-based recommendations ranked higher in social importance. This study has importance for theory in its examination of popularity-based news recommendations from the two theoretical viewpoints of collective intelligence and popularity bias and by its use of both qualitative (content analysis) and quantitative methods (questionnaires). It also sheds light on the differences in the role of media channels that fulfill an agenda-setting function and Internet news sites that treat news from the viewpoint of markets.

• Korean Journal of Biological Psychiatry
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• v.9 no.1
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• pp.50-61
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• 2002

Objectives:High nailfold plexus visibility can reflect central nervous system defects as an etiologic factor of schizophrenia indirectly. Previous studies suggest that this visibility is particularly related to the negative symptoms of schizophrenia and frontal lobe deficiency. In this study, we examined the relationships between nailfold plexus visibility, and various clinical variables and neuropsychological functions in schizo-phrenic patients. Methods:Forty patients(21males, 19 females) satisfying the DSM-IV criteria for schizophrenia and thirty eight normal controls(20 males, 18 females) were measured for Plexus Visualization Score(PVS) by using the capillary microscopic examination. For the assessment of psychopathology, process-reactivity, premorbid adjustment, and neuropsychological functions, we used Positive and Negative Syndrome Scale(PANSS), Ullmann-Giovannoni Process-Reactive Questionnaire(PRQ), Phillips Premorbid Adjustment Scale(PAS), Korean Wechsler Adult Intelligence Scale(KWIS), Continuous Performance Test(CPT), Wisconsin Card Sort Test (WCST), and Word Fluency Test. We also collected data about clinical variables. Results:PVS was correlated with PANSS positive symptom score and composite score negatively. There were no correlations between PVS and PRQ score, PAS score and neuropsychological variables respectively. Conclusions:This study showed that nailfold plexus visibility was a characteristic feature in some schizophrenic patients, and that higher plexus visibility was associated with the negative symptoms of schizophrenia. There was no association between plexus visibility and neuropsychological functions.

• Korean Journal of Remote Sensing
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• v.33 no.6_1
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• pp.917-930
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• 2017

To understand the temporal and spatial variations of surface chlorophyll-a concentration (Chl-a) distribution in the Indian Ocean ($30^{\circ}E{\sim}120^{\circ}E$, $30^{\circ}S{\sim}30^{\circ}N$) by the Indian Ocean Dipole (IOD), we conducted EOF and K means analyses of monthly satellite-derived Chl-a data in the region during 1998~2016 periods. Chl-a showed low values in the central region of the Indian Ocean and relatively high values in the upwelling region and around the marginal regions of the Indian Ocean. It also had a strong seasonal variation of Chl-a, showing the lowest value in the spring and the highest value in summer due to the change of the monsoon and current system. The EOF analysis showed that Chl-a variation in EOF mode 1 is related to ENSO (El $Ni{\tilde{n}}o$/Southern Oscillation) and that of mode 2 is linked to IOD. Both modes explained spatially opposite trends of Chl-a in the east and west Indian Ocean. From K means analysis, the Chl-a variation in the east and west Indian Ocean, and around India have relatively good relationship with IOD while that in the tropical and middle Indian Ocean closely associated with ENSO. The spatial and temporal distribution of Chl-a also showed distinct spatial and temporal variations depend on the different types of IOD events. IOD classifies two patterns, which occurred during the developing ENSO (First Type IOD) and the year following ENSO event (Second Type IOD). Chl-a variation in the First Type IOD started in summer and peaked in fall around the east and west Indian Ocean. Chl-a variation in the Second Type IOD occurred started in spring, peaked in summer and fall, and disappeared in winter. In the Chl-a variation related to IOD, developing process appearing in the Chl-a difference between the east and west Indian ocean was similar. Chl-a variation in the northern Indian Ocean were opposite trend with changing developing phase of IOD.

• The Korean Journal of Nuclear Medicine
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• v.37 no.6
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• pp.355-363
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• 2003

Purpose: Regional contractility can be calculated using the regional volume change of left ventricle measured by gated myocardial SPECT image and curve of central artery pressure obtained from radial artery pressure data. In this study, a program to obtain the regional contractility was developed, and reproducibility of regional contractility measurement was assessed. Materials and Methods: Seven patients(male:female=5:2, $58{\pm}11.9$ years) with coronary artery diseases underwent gated Tc-99m MIBI myocardial SPECT twice without delay between two scans. Regional volume change of left ventricle was estimated using CSA (Cardiac SPECT Analyzer) software developed in this study. Regional contractility was iteratively estimated from the time-elastance curve obtained using the time-pressure curve and regional time-volume curve. Reproducibility of regional contractility measurement assessed by comparing the contractility values measured twice from the same SPECT data and by comparing those measured from the pair of SPECT data obtained from a same patient. Results: Measured regional contractility was $3.36{\pm}3.38{mm}Hg/mL$ using 15-segment model, $3.16{\pm}2.25{mm}Hg/mL$ using 7-segment model, and $3.11{\pm}2.57{mm}Hg/mL$ using 5-segment model. The harmonic average of regional contractility value was almost identical to the global contractility. Correlation coefficient of regional contractility values measured twice from the same data was greater than 0.97 for all models, and two standard deviations of contractility difference on Bland Altman plot were 1.5%, 1.0%, and 0.9% for 15-, 7-, and 5-segment models, respectively. Correlation coefficient of regional contractility values measured from the pair of SPECT data obtained from a same patient was greater than 0.95 for all models, and two standard deviations on Bland Altman plot were 2.2%, 1.0%, and 1.2%. Conclusion: Regional contractility of left ventricle measured using developed software in this study was reproducible. Regional contractility of left ventricle will be a new useful index for myocardial function after analysis of the clinical data.

• The Journal of the Korean bone and joint tumor society
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• v.17 no.2
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• pp.79-86
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• 2011

Purpose: Modular tumor prosthesis is the most popular recontructive modality after resection of malignat tumor in extremity. Complications and survival of tumor prosthesis reconstruction are well-known. however, reports on the long-term outcome of tumor prosthesis in osteosarcoma patientss are scarece. Materials and Methods: In 158 cases as diagnosed as osteosarcoma from feburary 1989 to December 2006 in a single cancer center. We retrospectively reviewd 48 osteosarcoma patients who under went tumor prosthetic reconstruction. Mean follow up preiod was 75.6 months (range; 60 to 179 months). There were 28 males, 20 females and mean age was 22.4 years (range; 11-71). Pathologic subtypes were conventional central osteosarcoma in 46 cases and periosteal in 2 cases. The location of the tumor was proximal tibia (26 cases), distal femor (20 cases), femor diaphysis (1 case), and tibia diaphysis (1 case). In 41 cases built-up-type tumor prosthesis have been used and 7 cases expansion-type tumor prosthesis have been used. We used Musculoskeletal tumor society (MSTS) grading system to asses post operation function, and we analyzed survival rate of patient and tumor prosthesis and complication. Results: The overall survival rate was 77.7% and disease free survival rate was 68.9%. The survival rate of tumor prosthesis was 73%, in last follow up tumor prosthesis has been removed in 12 cases. All of them, 17 complications occurred, which included infection in 16 cases, Periprosthetic Fracture and Loosening of tumor prosthesis in 4 cases, articular instability in 4 cases. MSTS functional score was 74.1% in post operation. Conclusion: In long term follow up result, Primary tumor prosthesis -a reconstruction method after a wide extensional resecion of a bone tumor- can be a effective treatment method in asepect of survival rate, functional assesment and complication.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.1
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• pp.71-82
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• 2016

Through literature review and on-site survey of Gimcheon Bangcho pavilion(芳草亭), the features of garden design(庭園意匠) including geographic conditions, landscape modeling of Nujeong(樓亭) and Jidang(池塘, Pond), and scenic interpretations in Nujeong Jeiyoung poetry(樓亭題詠詩) have been carefully researched and the findings are presented below. Bangcho pavilion is located in a village called Wonteomaeul, which belongs to the feng shui state of golden hairpin and floating lotus. It has long been the cultural hub of communication and social interactions among the villagers. The Head House of Jeongyanggong(靖襄公宗宅), the main house(本第) of the Yeonan Yi Clan(延安李氏), is about 150m away from Bangcho pavilion, an artistic space whose landscape modeling is of the form called Nujeong. The name 'Bangcho' reflects the noble man(君子)'s determination: "I yearn for the place where honey parrots fly and the fragrant grass grow." From the two story structure of the pavilion where there is an additional floor installed to the central ondol room by a four-sided subdivision door, one can detect the aspiration of the men for pursuing an open view. One can also observe the efforts in designing the room to be used for multiple purposes from a private place to an office for periodic publication of a family lineage document called "Garyejunghae(家禮增解)". Bangcho pavilion's main sight of interest is Mrs Choi's Pond(崔氏潭), the one and only garden structure that comprises the twin round island of square pond(方池雙圓島) among the existing Jidangs in Korea. In this special Jidang, there are two coexisting islands that represent a well thought out garden facility for symbolizing conjugal affection and unyielding fidelity between master and servent(主從). In addition, the three inflows and one outflow facing the Ramcheon valley is regarded as an ideal garden design optimized for performing the function of a village bangjuk which is the site for undercurrent creation and ecological reprocessing. At present, Giant pussy willow is the only circular vegetation identified in the area of Bangcho pavilion, although this plant species is about to wither away judging from the signs of decrepitude that seems to persist for two out of three weeks. The old pine tree that appears in the 1872 Jeiyoung poetry of Byeongseon Song(宋秉璿) no longer exists. Anjae(安齋) Jang Yoo(張瑠)'s "Eight Scenary on Bangcho pavilion(芳草亭八詠)" and its expansive reproduction "Ten Scenary on Bangcho pavilion(芳草亭十景)" from Gwagang(守岡) Lee Manyoung(李晩永) depict vividly the pastoric scenery of an idyll(田園景) that stretches throughout the natural and cultural landscape of the province of Gimcheon and Guseong surrounding the Bangcho pavilion. The Bangcho pavilion sutra aims to establish Bangcho pavilion and the village of Wonteomaeul as the centre of microcosmos by dividing and allocating its scenic features according to the four seasons and times(四季四時), the eight courses(八方) and the meteorological phenomena, and it is the incarnation(顯現) of landscape perception upon the Byeol-seo Scenic site of Bangcho pavilion, the cultural hub of the region.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.11-24
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• 2003

This experimental studies was to investigate the location of PNS and CNS labeled neurons following injection of 2% WGA-HRP and pseudorabies virus (PRY), Bartha strain, into the ductus deferens of rats. After survival times 4-5 days following injection of 2% WGA-HRP and PRV, the rats were perfused, and their brain, spinal cord, sympathetic ganglia and spinal ganglia were frozen sectioned ($30{\mu}m$). These sections were stained by HRP histochemical and PRY inummohistochemical staining methods, and observed with light microscope. The results were as follows ; 1. The location of sympathetic ganglia projecting to the ductus deferens were observed in pelvic ganglion, inferior mesenteric ganglion and L1-6 lwnbar sympathetic ganglia. 2. The location of spinal ganglia projecting to the ductus deferens were observed in T13-L6 spinal ganglia. 3. The PRY labeled neurons projecting to the ductus deferens were observed in lateral spinal nucleus, lamina I, II and X of cervical segments. In thoracic segments, PRY labeled neurons were observed in dorsomedial part of lamina I, II and III, and dorsolateral part of lamina IV and V. Densely labeled neurons were observed in intermediolateral nucleus. In first lumbar segment, labeled neurons were observed in intermediolateral nucleus and dorsal commisural nucleus. In sixth lumbar segment and sacral segments, dense labeled neurons were observed in sacral parasympathetic nuc., lamina IX and X. 4. In the medulla oblongata, PRV labeled neurons projecting to the ductus deferens were observed in the trigeminal spinal nuc., A1 noradrenalin cells/C1 adrenalin cells/caudoventrolateral reticular nuc., rostroventrolateral reticular nuc., area postrema, nuc. tractus solitarius, raphe obscurus nuc., raphe pallidus nuc., raphe magnus nuc., parapyramidal nuc., lateral reticular nuc., gigantocellular reticular nuc.. 5. In the pons, PRV labeled neurons projecting to the ductus deferens were ohserved in parabrachial nuc., Kolliker-Fuse nuc., locus cooruleus, subcooruleus nuc. and AS noradrenalin cells. 6. In midbrain, PRV labeled neurons projecting to the ductus deferens were observed in periaqueductal gray substance, substantia nigra and dorsal raphe nuc.. 7. In the diencephalon, PRV labeled neurons projecting to the ductus deferens were observed in paraventricular hypahalamic nuc., lateral hypothalamic nuc., retrochiasmatic nuc. and ventromedial hypothalamic nuc.. 8. In cerebrum, PRV labeled neurons projecting to the ductus deferens were observed in area 1 of parietal cortex. These results suggest that WGA-HRP labeled neurons of the spinal cord projecting to the rat ductus deferens might be the first-order neurons related to the viscero-somatic sensory and sympathetic postganglionic neurons, and PRV labeled neurons of the brain and spinal cord may be the second and third-order neurons response to the movement of smooth muscles in ductus deferens. These PRV labeled neurons may be central autonomic center related to the integration and modulation of reflex control linked to the sensory and motor system monitaing the internal environment. These observations provide evidence for previously unknown projections from ductus deferens to spinal cord and brain which may be play an important neuroanatornical basic evidence in the regulation of ductus deferens function.