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The Pattern of Pusan Station Shopping District( I ) (부산역(釜山驛) 상점가(商店街)의 패턴( I ))

  • Kim, Won-Kyung
    • Journal of the Korean association of regional geographers
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    • v.5 no.1
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    • pp.25-75
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    • 1999
  • This study concern with the pattern of Pusan Station Shopping District within Pusan City, Korea, one of the third ranked centers within Pusan-the first ranked is CBD, the second is subCBD, the third are Spa Shopping district, Tongnae shopping district, Jobang-Ap shopping district and Yangjeong shopping district. This paper serves as a part of series studies which attempt to clarify the internal structure of Pusan as a whole. Part(I) of this study deals with the pattern of functions including information & culture, business, recreation and retailing. The results are as follows. 1. Pusan Station is one of higher ranked class of central places within Pusan City. But the ratio of dwelling houses is the highest in Pusan Station among the 9 higher ranked central places within Pusan. It means that the residential areas still remain along the maze type of narrower streets inner part of the blocks, especially western belt of this shopping district. 2. Business functions are one of the important criteria which classified the central places within the city and Pusan Station is the first ranked shopping districts in terms of these criteria among the 9 higher ranked central places including CBD within Pusan City. It suggests that Pusan Station is the miniature of the CBD, SubCBD is not the miniature of CBD in the view point of business function. It also means that Pusan Station Shopping District has been developed as a special shopping district or as a special central place. It has not been evolved as a center of the hierarchy of central places within the city by the natural or organic growth. 3. Pusan Station as 'the third space or drinking place' and it's characteristics as a amusement center presents at so called the 'Texas Town'-free tax area- whose customers are mainly U. S. soldiers and foreign sailors. But from the 1990s, this 'Town' changed to 'Russian Town', You can easy to meet many Russians and Russian lettered signboards-not English- along the street. 4. Convenient stores distribute mainly at back streets or along the narrower streets. It means that this kinds of stores have a residential oriented character. And a certain convenient stores locate with almost same distances. It suggests that it's hinterland is limited in nearer neighborhoods.

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A Study of Unregistered Manufacturing Plants: Their Problems and Alternative Policies (首都圈 無登錄工場 問題와 對策에 관한 硏究)

  • Hwang, Man-Ik
    • Journal of the Korean Geographical Society
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    • v.31 no.3
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    • pp.489-507
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    • 1996
  • The purpose of this study is to examine the increasing number of unregistered manufacturing plants and related problems, and to recommend alternative solutions to the problems. Data are obtained from a field survey of randomly selected small scale manufacturing plants in Seoul and its suburban cities. A total number or respondents are 533, and 416 of them are unregistered plants. The Capital Regional Planning has had a goal during last three decades to lead a balanced regional economic development by restriction manufacturing plants in the Capital Region and by encouraging them in other regions in the nation. It was 1984 when a comprehensive planning was established to achieve this goal. Sets of various regulations, by-laws and codes have been implemented to regulate manu-facturing activities in the Capital Region to achieve the goal. The region is divided into three sub-regions, and a different degree of regulations is applied to each sub-region. Only a certain types of industries are allowed in a particular sub-region. For instance, a plant manufacturing high-technology products could be allowed in the most urbanized sub-region. All manu-facturing plant in the Capital Region which has ares size of larger than 200"\;"$m^2$ is compulsory to register to the local government office. In practice, however, it is not common or sometimes almost impossible to get approval for many applicant manufacturers because of strict regulations. There have been increasing number of plants in the Capital Region during last several decades, despite the strict regulations. Many of those newly established plants are without formal registration at the local administration office. howerver. These are so called 'unregisterd' plants. Surveyed data and many government official data show that many of unregistered plants have been established in recent years. which indicate that current regulations are no longer effective. The number of unregistered plants are increasing tin the Capital Region because of many locational advantages in the region for plants, particularly those in small scale. Unregistered plants are the source of many problems, such as local water pollution or noise pollution in residential areas. There are also many administration problems, bed\cause they are not registered. The central government has attempted to cure the problems of unregistered plants. For example, the government allowed a unregistered plant to remain at present site for three ydars, if it met certain conditions in three years. However, this program was unsuccessful because many of those plants were not able to meet the concitions. Three times the government renewed the term for those which did not meet conditions since 1989, but it was afraid to be without success. There are many evidences that current policies to control manufacturing plants are not effective. The Capital Region must face mounting problems if ploicies are not reformed soon. This study suggests that the policy of the Capital Regional Planning has to be reoriented to provide more favorable policies for manufacturing plants in the Capital Region than current regulations which is aimed to restrict manufacturing activities. It is time to improve many existing problems in the region through reforms and of current regulations to foster unregistered plants. This study also proposes many smaller-area sub-divisions instead of current three large area sub-regions which is too broad to apply single kind of regulation, or codes. Flexible regulations and codes can be applied to such a small-area sub-divivisions based on location and industrial characteristics of the individual sub-divisions. It is necessary to provide decent industrial environment in the Capital Region, which is best equipped to provide many favorable industrial locational factors in the nation, thus this nation can be further prepared to compete in an inter-national market at an era of globalization in manufacturing.

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Limited Open Reduction and Internal Fixation of the Tibial Pilon Fractures (제한 절개를 통한 관혈적 정복 및 내고정술을 이용한 경골 Pilon 골절의 치료)

  • Kang, Chung-Nam;Kim, Jong-Oh;Kim, Dong-Wook;Koh, Young-Do;Ko, Sang-Hun;Yoo, Jae-Doo;Hwang, Jun-Ho
    • Journal of Korean Foot and Ankle Society
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    • v.1 no.2
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    • pp.102-111
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    • 1997
  • The tibial Pilon fracture, which is defined as a comminuted intraarticular fracture of the distal tibia, is difficult to manage because high axial compression and rotational forces to the ankle joint result in impaction, severe comminution, metaphyseal disruption and soft tissue damage. There are variable methods of treatment such as manipulation and cast, calcaneal traction and cast, external fixation, pin and plaster, limited open reduction and external fixation, and open reduction and rigid internal fixation. Though most of authors reported better result after a surgical treatment. than that of conservative treatment, many complications such as posttraumatic arthritis and soft tissue problem still remain troublesome. We have reviewed 19 cases of the tibial Pilon fractures in 18 patients which were treated with limited open reduction and internal fixation from September 1993 to May 1996. The results were as follows: 1. The fractures were classified into five types according to the system of Ovadia and Beals, and the most frequent type was type 3 (53%). The most common cause of injury was traffic accident (47%). 2. All of the cases of type 1 and 2, in which the injury of the ankle joint was less severe, revealed good or excellent clinical results. But in type 4 and 5, because the injury is much severe and accurate reduction is difficult, the clinical results were unsatisfaetory. 3. The most frequent complication was posttraumatic osteoarthritis, and which developed in second frequent complication, was developed m the three cases of type 3 in which the radiographic results were less than fair, but there were no correlation with the clinical results. 4. We could markedly reduce the complications related to the soft tissue problem of Pilon fracture by treatment with limited open reduction and internal fixation, and consider that this is a good method of treatment of Pilon fracture when the injury is less severe and accurate reduction is possible.

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토양 및 지하수 Investigation 과 Remediation에 대한 현장적용

  • Wallner, Heinz
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2000.11a
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    • pp.44-63
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    • 2000
  • Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

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Combined Treatment of Residual, Recurrent and Unresectable Gastric Cancer (수술후 잔존 위암, 재발성 위암 및 절제 불가능한 위암의 병용 요법)

  • Bae, Hoon-Sik
    • Radiation Oncology Journal
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    • v.8 no.1
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    • pp.85-93
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    • 1990
  • A series of 25 patients with residual, recurrent, and unresectable gastric cancer received various combination of surgery, radiotherapy (RT), chemotherapy (CT), and hyperthermia (HT). They were placed into 7 categories; 1) CT and HT-14 patients; 2) RT and HT-15 patients; 3) surgery, RT and HT-2 patients; 4) surgery, RT, HT and CT-1 patient; 5) RT, HT and CT -1 patient; 6) RT and CT-1 patient; 7) RT alone-1 patient. Three patients had curative resection. 21 patients received irradiation with tightly contoured portals to spare as much small bowel, kidney and marrow as possible. Hyperthermia was applied regionally once or twice a week for 23 patients using 8 MHz radiofrequency capacitive heating device (Thermotron RF-8). HT was given approximately 30 min after RT 7 patients were treated with CT: 4 patients received HT and concomitant Mitomycin-C; 3 patients received HT and sequential 5-FU+Adriamycin+Mitomycin-C. There was not any treatment related deaths. There was also no evidence of treatment related problems with liver, kidney, stomach, or spinal cord except only one case of transient diabetic ketoacidosis. The tumor response was evaluable in 22 patients. None achieved complete remission.11 ($50\%$) achieved partial remission. The response rate was correlated with total radiation dose and achieved maximum temperature. 9 of 14 ($64\%$) received more than 4000 cGy showed partial remission; especially, all 3 patients received more than 5500 cGy achieved partial response.8 of the 12 patients ($67\%$) who achieved maximal temperature more than $41^{\circ}C$ showed partial response in comparing with $25\%$ (2 of 8 patients, below $41^{\circ}C$). The numbers of HT, however, was not correlated with the response. 3 of the 25 patients ($12\%$) remain alive. The one who was surgically unresectable and underwent irradiation alone is in progression of the disease with distant metastases. The remaining two patients with curative resection are alive with free of disease, 24 and 35 months, respectively. The median survival by response are 11.5 months in responders and 4.6 months in non-responders.

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Adaptive Response to ionizing Radiation Induced by Low Doses of Gamma Rays in Human Lymphoblastoid Cell Lines (인체임파양세포에서 저선량의 감마선에 의해서 유도되는 적응 반응)

  • Seong, Jin-Sil;Suh, Chang-Ok;Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.1-8
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    • 1994
  • When cells are exposed to low doses of a mutagenic or clastogenic agents. they often become less sensitive to the effects of a higher dose administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher dose (50 cGy), The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines, which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism.

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Postoperative Radiotherapy for Locally Advanced Gastric Cancer (국소적으로 진행된 위암의 수술후 방사선 치료성적)

  • Lee Myung Za;Chun Ha Chung;Kim Insoon;Chung Tejune
    • Radiation Oncology Journal
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    • v.15 no.2
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    • pp.113-119
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    • 1997
  • Purpose : Radical gastrectomy is main treatment of gastric cancer. But the result is not satisfactory with surgery alone. Most of pattern of failure remain locoregional recurrence. To improve 5 year survival postoperative chemotherapy with or without radiotherapy has been used. We analyzed patients with stage III and IV stomach cancer who had radical operation and received postoperative radiation therapy combined with or without chemotherapy retrospectively. Material and Method : From March 1985 to June 1993, 68 patients treated with curative resection and received postoperative adiuvant radiotherapy with 36Gy or more were evaluated. Median age was 60 years(range 28-66 yrs) . Patients were followed from 3 to 133 months with median follow up of 48 months. Thirty seven patients had non signet ring adenocarcinoma, 29 signet ring cell, 2 other cell. Patients with stage IIIA, IIIB, IV disease were 19, 25 and 24 respectively Chemotherapy was given to all patients except two. Results : Five-year overall survival and disease-free survival rate were 36.6% and 33.6%, respectively. Prognostic factor affecting survival were assessed. High ratio of jnvolved/dissected Iymph node, signet ring histology showed Poor Prognosis with statistical significance. Presence of residual tumor after surgery, stageIV. split course of radiation therapy, age, number of involved Iymph node, number of Iymph node dissection and grade of tumor affected survival without statistical significance, Type of chemotherapy did not affect survival. Recurrence was documented in 34 patients. High recurrence was seen in omentum and peritoneum with 23.5%, and remnant stomach, anastomosis site, A-loop and I-loop had also high recurrence with 13.2%. In field locoregional recurrence was 20.7% and total distant metastases were 39.7%. Total intraabdominal failure was 47.1% and extraabdominal failure was 13.2%. Treatment toxicity was considered to be acceptable. 22.1% of patients had grade 3 and only 1 patient had grade 4 leukopenia. Six Patients(8.8%) had weigh loss more than 10%. Conclusion : Treatment toxicity was acceptable with combined treatment with chemotherapy and radiotherapy. Locoregional recurrence was relatively low compared to distant failure with addition of irradiation. Peritoneal and omental seeding was high Five-rear surival was increased with combined modality. Radiation may eradicate minimal residual disease and improve survival, To evaluate role of radiation Prospective randomized study employing chemotherapy alone and chemotherapy plus radiation is necessary. Futhermore to reduce intraabdominal failure, role of intraabdominal chemotherapy in addition to combined chemotherapy plus radiation has to be explored.

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The Impact of Perceived Risks Upon Consumer Trust and Purchase Intentions (인지된 위험의 유형이 소비자 신뢰 및 온라인 구매의도에 미치는 영향)

  • Hong, Il-Yoo B.;Kim, Woo-Sung;Lim, Byung-Ha
    • Asia pacific journal of information systems
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    • v.21 no.4
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    • pp.1-25
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    • 2011
  • Internet-based commerce has undergone an explosive growth over the past decade as consumers today find it more economical as well as more convenient to shop online. Nevertheless, the shift in the common mode of shopping from offline to online commerce has caused consumers to have worries over such issues as private information leakage, online fraud, discrepancy in product quality and grade, unsuccessful delivery, and so forth, Numerous studies have been undertaken to examine the role of perceived risk as a chief barrier to online purchases and to understand the theoretical relationships among perceived risk, trust and purchase intentions, However, most studies focus on empirically investigating the effects of trust on perceived risk, with little attention devoted to the effects of perceived risk on trust, While the influence trust has on perceived risk is worth studying, the influence in the opposite direction is equally important, enabling insights into the potential of perceived risk as a prohibitor of trust, According to Pavlou (2003), the primary source of the perceived risk is either the technological uncertainty of the Internet environment or the behavioral uncertainty of the transaction partner. Due to such types of uncertainty, an increase in the worries over the perceived risk may negatively affect trust, For example, if a consumer who sends sensitive transaction data over Internet is concerned that his or her private information may leak out because of the lack of security, trust may decrease (Olivero and Lunt, 2004), By the same token, if the consumer feels that the online merchant has the potential to profit by behaving in an opportunistic manner taking advantage of the remote, impersonal nature of online commerce, then it is unlikely that the merchant will be trusted, That is, the more the probable danger is likely to occur, the less trust and the greater need to control the transaction (Olivero and Lunt, 2004), In summary, a review of the related studies indicates that while some researchers looked at the influence of overall perceived risk on trust level, not much attention has been given to the effects of different types of perceived risk, In this context the present research aims at addressing the need to study how trust is affected by different types of perceived risk, We classified perceived risk into six different types based on the literature, and empirically analyzed the impact of each type of perceived risk upon consumer trust in an online merchant and further its impact upon purchase intentions. To meet our research objectives, we developed a conceptual model depicting the nomological structure of the relationships among our research variables, and also formulated a total of seven hypotheses. The model and hypotheses were tested using an empirical analysis based on a questionnaire survey of 206 college students. The reliability was evaluated via Cronbach's alphas, the minimum of which was found to be 0.73, and therefore the questionnaire items are all deemed reliable. In addition, the results of confirmatory factor analysis (CFA) designed to check the validity of the measurement model indicate that the convergent, discriminate, and nomological validities of the model are all acceptable. The structural equation modeling analysis to test the hypotheses yielded the following results. Of the first six hypotheses (H1-1 through H1-6) designed to examine the relationships between each risk type and trust, three hypotheses including H1-1 (performance risk ${\rightarrow}$ trust), H1-2 (psychological risk ${\rightarrow}$ trust) and H1-5 (online payment risk ${\rightarrow}$ trust) were supported with path coefficients of -0.30, -0.27 and -0.16 respectively. Finally, H2 (trust ${\rightarrow}$ purchase intentions) was supported with relatively high path coefficients of 0.73. Results of the empirical study offer the following findings and implications. First. it was found that it was performance risk, psychological risk and online payment risk that have a statistically significant influence upon consumer trust in an online merchant. It implies that a consumer may find an online merchant untrustworthy if either the product quality or the product grade does not match his or her expectations. For that reason, online merchants including digital storefronts and e-marketplaces are suggested to pursue a strategy focusing on identifying the target customers and offering products that they feel best meet performance and psychological needs of those customers. Thus, they should do their best to make it widely known that their products are of as good quality and grade as those purchased from offline department stores. In addition, it may be inferred that today's online consumers remain concerned about the security of the online commerce environment due to the repeated occurrences of hacking or private information leakage. Online merchants should take steps to remove potential vulnerabilities and provide online notices to emphasize that their website is secure. Second, consumer's overall trust was found to have a statistically significant influence on purchase intentions. This finding, which is consistent with the results of numerous prior studies, suggests that increased sales will become a reality only with enhanced consumer trust.

Effects of Scutellaria radix Extract on Osteoblast Differentiation and Osteoclast Formation (황금 추출물이 조골세포와 파골세포의 활성에 미치는 영향)

  • Shin, Jeong-Min;Park, Chan-Kyung;Shin, Eun-Ju;Jo, Tae-Hyung;Hwang, In-Kyeong
    • Korean Journal of Food Science and Technology
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    • v.40 no.6
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    • pp.674-679
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    • 2008
  • Scutellaria radix (SR) has been utilized as a traditional medicine for a variety of diseases including Rheumatoid arthritis and its major flavonoids - baicalein, baicalin, and wogonin - have been reported to exert beneficial health effects, including anti-bacterial, anti-viral, anti-inflammatory, and free-radical scavenging. However, the mechanisms underlying this effect remain poorly understood. The principal objective of this study was to determine the effect of SR on osteoblast and osteoclast cells. SR extract was prepared using 70% ethanol solvent. Osteoblastic MC3T3-E1 cells and osteoclast precursor Raw 264.7 macrophage cells were utilized. SR extract increased MC3T3-E1 cell proliferation and stimulated alkaline phosphatase activity dose-dependently, 152.0% of the control at concentration $1{\mu}g/mL$. Additionally, SR extract ($1{\mu}g/mL$) stimulated Bone nodule formation activity in MC3T3-E1 cells, approximately 223.3% of the control, 20 days after the exposure. In addition, SR extract significantly reduced the number of tartrate-resistant acid phosphatase-positive (TRAP+) multinucleated cells from Raw 264.7 cells. In conclusion, SR extract stimulates the proliferation and bioactivities of boneforming osteoblasts, and inhibits the activities of bone-resorbing osteoclasts to a certain degree.

Study on Marteilioides chungmuensis Comps et al., 1986 Parasite of the Pacific Oyster, Crassostrea gigas Thunberg (참굴의 난(卵)에 기생(寄生)하는 Marteilioids chungmuensis Comps et al., 1986에 관하여)

  • Park, Mi-Seon;Chun, Seh-Kyu
    • Journal of fish pathology
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    • v.2 no.2
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    • pp.53-70
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    • 1989
  • An ovarian parasite, Marteilioides chungmuensis of the Pacific oyster, Crassostrea gigas has been observed on several occasions in the Pacific sector of production of this oyster species(Matsuzato et al., 1977 ; Chun, 1979). This study was carried out on the specimens collected at Hwado, Och'$\check{o}$n, and Sinchang respectively located the southern, western, and eastern coasts of Korean Peninsula from 1986 through 1988 to investigate M. chungmuensis to the Pacific oyster. Uitrastructural studies were also carried out on infected oysters, to allow detailed examination of the structure and consepuently the systematic position of this parasite. Infection rates of M. chungmuensis at Hwado and Och'$\check{o}$n oyster farms were 5.3% and 4.2% each in 1986, 6.7% and 2.8% each in 1987, but they were not found at Sinchang oyster habitat. M,. chungmuensis-infected oysters were found from June to November at Hwado and from June to October at Och'$\check{o}$n. Twenty five of three hundred oysters transplanted from Sinchang to Hwado were found infected with M. chungmuensis. Some abnormal eggs infected with M. chungmuensis are liberated through the gill together with normal mature eggs on the spawning and the rest remain necrotized after spawning season. The earliest known stages consist of a stem cell or primary cell, including a secondary cell in which ovoid haplosporosomes are found. During sporulation, 2 or 3 secondary are produced by exogenous budding from the first secondary cell and, each secondary cell evolves into a sporont upon the tertiary cell differentiation (enodogenous budding) ; then, haplosporosomes are formed in the young sporont. Internal cleavages involve the differentiation of one tricellular spore per sporont. The outermost spore cell contains membrane-bounded osmiophilic bodies : the middle and the inner, most spore cells contain high density cytoplasmic ribosomes. The mechanism of spore formation from the stem cell of M. chungmuensis is the simplest of the class Paramyxea known up to now.

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