• Title/Summary/Keyword: Controversy

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A study on the library reference service fees (도서관봉사요금에 관한 일고찰)

  • 손연옥
    • Journal of Korean Library and Information Science Society
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    • v.12
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    • pp.35-59
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    • 1985
  • User fees have been employed by libraries as far back as the mid-1800s in both United States and England. By the late 1800s and early : 1900s, the charging of user fees for some library products and services had become a reality in many public and academic libraries. Yet the practice has created controversy when computer-aided reference service began to charge especially in the publicly funded libraries. There are two extream arguments on library reference service fees : one is for and the other is against. most fee o n.0, pponents base their stand on morality. They argue that charging fees for any service is wrong because it violates the user's right of access to information and regard it as an act of decrease human life chances as well as an act of censor. But those who favour fees argue that it is necessary to separate the rhetoric from the reality and to distinguish what libraries are from what they do. The study revealed that library has two options. One is strict free of charge and the other is charging for selected library services. Whatever options the library may take, library had to decide an overall reference service policy. The level and scope of service, audience, necessary fund (who and how) and many other physical and metaphysical things must be considered. However, the first option will necessary be to limit services while there is no loss of traditional philosophical service element. Yet, if to provide a wide range of choices and to create conditions more hospitable to competition from the private information sector and for better evolutional selection, the second option(fee-based service) gives more benefit to the users while there is a loss of fundamental service philosophy.

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Effect of Cyclin D2 on Cell Proliferation in T-47D Breast Cancer Cells (인체 유방암 세포에서 과다발현 시킨 Cyclin D2의 영향에 대한 연구)

  • 김현준;이근수;전상학;공구
    • Environmental Mutagens and Carcinogens
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    • v.24 no.1
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    • pp.1-9
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    • 2004
  • Three D-type cyelins (D1, D2, and D3) are expressed in G1 phase of the cell cyele and have been implicated in cell transformation and neoplasia in human and mouse. Cyclin D1 overexpression or amplification was described in various human cancers. However, there is controversy about the role of cyclin D2 in cell cyele progression and human carcinogenesis. Specially, loss of cyelin D2 is involved in a vital tumor suppressor function in normal breast tissue, and that its loss may be related to tumorigenesis. The author examined to effect over-expression of cyclin D2 on the cell proliferation, apoptosis, and cell cycle using cyclin D2 transfected stable T47D breast cancer cells to investigate whether cyclinD2 functions as a positive regulator or negative regulator in cell proliferation. Overexpression of cyclin D2 led to the suppression of cell growth in cyclin D2 transfected T47D in both in its expression level and a time dependent manner with up to 50% reduction of cell growth at 72 hours. Therefore, the authors performed the cell cycle phase analysis using the flow cytometry to investigate the effect of cyclin D2 on the cell cycle phase in cyclin D2 transfected stable T47D cells. The flow cytometry analysis revealed increased sub G0 phase in cyclin D2 transfeted cells up to 23% at 72 hours. To confirm these results induced by overexpression of cyclinD2, the apoptotic bodies were counted in control and cyclin D2 transfected T47 cells. There are markedly increases of apoptotic bodies in cyclin D2-transfected cells up to 18%. These results suggested that Cyclin D2 suppresses the cell proliferation in breast cancers cells via the induction of apotosis.

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MAGNETIC HELICITY PUMPING BY TWISTED FLUX TUBE EXPANSION

  • CHAE JONGCHUL;MOON Y.-J.;RUST D. M.;WANG HAIMIN;GOODE PHILIP R.
    • Journal of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.33-41
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    • 2003
  • Recent observations have shown that coronal magnetic fields in the northern (southern) hemisphere tend to have negative (positive) magnetic helicity. There has been controversy as to whether this hemispheric pattern is of surface or sub-surface origin. A number of studies have focused on clarifying the effect of the surface differential rotation on the change of magnetic helicity in the corona. Meanwhile, recent observational studies reported the existence of transient shear flows in active regions that can feed magnetic helicity to the corona at a much higher rate than the differential rotation does. Here we propose that such transient shear flows may be driven by the torque produced by either the axial or radial expansion of the coronal segment of a twisted flux tube that is rooted deeply below the surface. We have derived a simple relation between the coronal expansion parameter and the amount of helicity transferred via shear flows. To demonstrate our proposition, we have inspected Yohkoh soft X-ray images of NOAA 8668 in which strong shear flows were observed. As a result, we found that the expansion of magnetic fields really took place in the corona while transient shear flows were observed in the photosphere, and the amount of magnetic helicity change due to the transient shear flows is quantitatively consistent with the observed expansion of coronal magnetic fields. The transient shear flows hence may be understood as an observable manifestation of the pumping of magnetic helicity out of the interior portions of the field lines driven by the expansion of coronal parts as was originally proposed by Parker (1974).

18F-2-Deoxy-2-Fluoro-D-Glucose Positron Emission Tomography: Computed Tomography for Preoperative Staging in Gastric Cancer Patients

  • Youn, Seok Hwa;Seo, Kyung Won;Lee, Sang Ho;Shin, Yeon Myung;Yoon, Ki Young
    • Journal of Gastric Cancer
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    • v.12 no.3
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    • pp.179-186
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    • 2012
  • Purpose: The use of 18F-2-deoxy-2-fluoro-D-glucose positron emission tomography-computed tomography as a routine preoperative modality is increasing for gastric cancer despite controversy with its usefulness in preoperative staging. In this study we aimed to determine the usefulness of preoperative positron emission tomography-computed tomography scans for staging of gastric cancer. Materials and Methods: We retrospectively analyzed 396 patients' positron emission tomography-computed tomography scans acquired for preoperative staging from January to December 2009. Results: The sensitivity of positron emission tomography-computed tomography for detecting early gastric cancer was 20.7% and it was 74.2% for advanced gastric cancer. The size of the primary tumor was correlated with sensitivity, and there was a positive correlation between T stage and sensitivity. For regional lymph node metastasis, the sensitivity and specificity of the positron emission tomography-computed tomography were 30.7% and 94.7%, respectively. There was no correlation between T stage and maximum standardized uptake value or between tumor markers and maximum standardized uptake value. Fluorodeoxyglucose uptake was detected by positron emission tomography-computed tomography in 24 lesions other than the primary tumors. Among them, nine cases were found to be malignant, including double primary cancers and metastatic cancers. Only two cases were detected purely by positron emission tomography-computed tomography. Conclusions: Positron emission tomography-computed tomography could be useful in detecting metastasis or another primary cancer for preoperative staging in gastric cancer patients, but not for T or N staging. More prospective studies are needed to determine whether positron emission tomography-computed tomography scans should be considered a routine preoperative imaging modality.

Biophysical Effects Simulated by an Ocean General Circulation Model Coupled with a Biogeochemical Model in the Tropical Pacific

  • Park, Hyo-Jin;Moon, Byung-Kwon;Wie, Jieun;Kim, Ki-Young;Lee, Johan;Byun, Young-Hwa
    • Journal of the Korean earth science society
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    • v.38 no.7
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    • pp.469-480
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    • 2017
  • Controversy has surrounded the potential impacts of phytoplankton on the tropical climate, since climate models produce diverse behaviors in terms of the equatorial mean state and El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) amplitude. We explored biophysical impacts on the tropical ocean temperature using an ocean general circulation model coupled to a biogeochemistry model in which chlorophyll can modify solar attenuation and in turn feed back to ocean physics. Compared with a control model run excluding biophysical processes, our model with biogeochemistry showed that subsurface chlorophyll concentrations led to an increase in sea surface temperature (particularly in the western Pacific) via horizontal accumulation of heat contents. In the central Pacific, however, a mild cold anomaly appeared, accompanying the strengthened westward currents. The magnitude and skewness of ENSO were also modulated by biophysical feedbacks resulting from the chlorophyll affecting El $Ni{\tilde{n}}o$ and La $Ni{\tilde{n}}a$ in an asymmetric way. That is, El $Ni{\tilde{n}}o$ conditions were intensified by the higher contribution of the second baroclinic mode to sea surface temperature anomalies, whereas La $Ni{\tilde{n}}a$ conditions were slightly weakened by the absorption of shortwave radiation by phytoplankton. In our model experiments, the intensification of El $Ni{\tilde{n}}o$ was more dominant than the dampening of La $Ni{\tilde{n}}a$, resulting in the amplification of ENSO and higher skewness.

Effect of resorbable membrane on immediate placement of implant in extraction socket during periradicular surgery (치근단 수출 시 형성된 골결손 부위를 가진 치아의 발치 후 즉시 식립 임플란트에서 골 접촉률에 대한 흡수성 차폐막의 효과)

  • Yang, Seung-Min;Kye, Seung-Beom;Shin, Seung-Yun
    • Journal of Periodontal and Implant Science
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    • v.38 no.4
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    • pp.603-610
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    • 2008
  • Purpose: The guided bone regeneration (GBR) technique is widely used in periradicular surgery. However, there is still some controversy regarding the effectiveness of GBR in promoting bone healing after periradicular surgery. The purpose of this study was to evaluate the resorbable membrane on the osteointegration of immediate implants in sites with periradicular lesion that had been removed by periradicular surgery. Materials and methods: Six roots of lower second premolars and 15 roots of lower third and fourth premolars of dogs were used as control and experimental teeth, respectively. Periradicular lesions were induced only in the experimental teeth. Twelve weeks later, the control and experimental teeth were extracted and implants were placed immediately. Periradicular lesions were removed with osteotomy, curettage and saline irrigation. Resorbable membranes were used in experimental group 1 but not in experimental group 2. After 12 week of healing period, the implants were clinically not mobile and showed no signs of infection. Data obtained by histomorphometric analysis were analyzed by Kruskal-Wallis test. Results: The control group showed a significantly higher bone to implant contact (BIC) ($74.14{\pm}16.18$) than experimental group 1 ($40.28{\pm}15.96$) and 2 ($48.70{\pm}17.75$)(p<0.05). However, there was no significant difference between experimental group 1 and 2. Conclusion: Although BIC in experimental groups were lower than in control group, immediate implant can be successfully placed at extraction socket with periradicular lesion and osseous defect. However, the use of resorbable membrane in bony defect created during periradicular surgery was questioned.

Comparative observations of lingualized occlusion and monoplane occlusion in the treatment of severe atrophy of edentulous mandible (심한 하악 치조골 흡수를 보이는 환자에서 설측 교두 교합과 단일평면 교합을 비교 관찰한 의치 수복 증례)

  • Ahn, Gyo-zin;Lee, Joon-Seok
    • Journal of Dental Rehabilitation and Applied Science
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    • v.34 no.2
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    • pp.127-136
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    • 2018
  • The patient who has severely absorbed residual ridges, treatments are challenging to satisfy many factors: support, retention, stability, etc. The neutral zone or monoplane occlusion with non-anatomical tooth would be helpful to get additional retention and stability. The monoplane occlusion has been used long time because it can eliminate horizontal forces and many other advantages. The lingualized occlusion was introduced to improve chewing efficiency and esthetics. But from a stability aspect, it seems controversy between monoplane occlusion and lingualized occlusion. This case report shows the results of the treat two flat residual ridge patients using functional impression; piezography, and made 2 other dentures with monoplane and lingualized occlusion that patient can select denture.

Major Hemothorax Induced Hypovolemic Shock Fallowing Administration of Intrapleural Urokinase (늑막강내 Urokinase 주입후 발생된 Major Hemothorax에 기인된 Hypovolemic shock)

  • Kim, Jung Kyu;Jung, In Beom;Son, Ji Woong;Choi, Eugene;Na, Moon Jun;Lee, Won Young;Cho, Young Jun
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.5
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    • pp.465-469
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    • 2004
  • Exudative pleural effusion can arise from pneumonia, tuberculosis, cancer, etc. Early drainage is needed for prevention of complications such as pleural fibrosis, thickening, bronchopleural fistulae and decline of lung function. Intrapleural Instillation of fibrinolytic enzymes has been used for 50years as an adjunct in the removal of fibrous material, hematoma and pus from the thoracic cavity. By the local fibrinolytic effect on fibrinous exudates within the pleural space, fibrinolytic agent has improved results of chest tube or pig tail drainage. But there were no controlled randomized studies, so significant controversy exists concerning the efficacy of this therpy, especially tuberculous pleurisy. Furthermore about complication, severe spontaneous bleeding has not been reported with intrapleural urokinase. Intrapleural fibrinolytic enzymes has shows no systemic complication. When it is administrated intravenously, not into intrpleural space, major bleeding is reported about 1-3% of patient, especially they had systemic disease, such as coagulation abnormalities. This case report presents a patient who suffered major hemothorax induced hypovolemic shock following the administration of 100,000 units of urokinase intrapleurally. He was 25-year old male with tuberculosis pleurisy without systemic illness demonstraion.

Climate Change and Depletion of Walleye Pollock Resources in the East Sea (기후변화와 동해안에서의 명태 자원의 고갈)

  • Kim, Jong-Gyu;Kim, Joong-Soon
    • Journal of Environmental Health Sciences
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    • v.44 no.3
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    • pp.259-266
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    • 2018
  • Objectives: Considered the "national fish" in Korea, the walleye pollock (Gadus chalcogrammus) has disappeared in the East Sea (Sea of Japan), a main habitat and fishing ground for the species. The reason for the disappearance is still a matter of controversy. This study was performed to investigate the long-term relationship between the walleye pollock catch and various meteorological and oceanographic factors in these waters. Methods: Fishery data on walleye pollock and data on meteorological and marine environmental factors over the 30 years (1981-2010) were obtained from the official national database. Time series analysis and correlation and regression analyses were performed to study the relationships. Results: Both air temperature and sea surface temperature in the East Sea rose over these 30 years, and the latter became more prominent. Salinity and dissolved oxygen showed a tendency to decrease while concentrations of nutrients such as nitrite nitrogen and nitrate nitrogen showed an increasing tendency. Sea surface temperature, air temperature, atmospheric pressure, and wind grade were negatively correlated with the catch size of walleye pollock (p<0.05), but salinity was positively correlated (p<0.001). Conclusion: The results of this study indicate that climate change, especially ocean warming, affected the habitat of walleye pollock. The results also indicate that lower sea surface and air temperatures, milder wind grade, and higher salinity were preferred for the survival of the fish species. It is necessary to pay attention to changes of the ocean ecosystem in terms of environmental pollution as well as seawater temperature.

Effect of Simvastatin on the Migration and Invasion of U-373-MG Cells (U-373-MG 세포의 이동 및 침윤에 미치는 simvastatin의 효과)

  • Kim, Hwan-Gyu
    • KSBB Journal
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    • v.25 no.3
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    • pp.265-270
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    • 2010
  • Simvastatins are widely used to reduce endogenous cholesterol synthesis and improve hypercholesterolemia. Also, simvastatin have been shown to induce both angiogenic and angiostatic responses. In this study, It was attempted to resolve this controversy by studying the effects of simvastatin on the cell migration and invasion with the proteinases secretion and expression pattern. U-373-MG cells treated with low dose of simvastatin ($0.001{\sim}0.5\;{\mu}M$) showed the induction of migration and invasion compared with the addition of a control buffer. On the contrary, high dose of simvastatin ($1{\sim}20\;{\mu}M$) showed the reduction of migration and invasion compared with the addition of a control buffer. It was also showed that simvastatin-regulated migrative and invasive phenotypes were consistent with the secretion and expression pattern of matrix metalloproteinase-2 (MMP-2), MMP-9 and plasmin.