• Nuclear Medicine and Molecular Imaging
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• v.41 no.6
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• pp.553-560
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• 2007

Purpose: We evaluated the standard uptake value (SUV) of F-18 FDG at PET/CT for differentiation of benign from malignant tumor in primary musculoskeletal tumors. Materials and Methods: Forty-six tumors (11 benign and 12 malignant soft tissue tumors, 9 benign and 14 malignant bone tumors) were examined with F-18 FDG PET/CT (Discovery ST, GE) prior to tissue diagnosis. The maxSUV(maximum value of SUV) were calculated and compared between benign and malignant lesions. The lesion analysis was based on the transverse whole body image. The maxSUV with cutoff of 4.1 was used in distinguishing benign from malignant soft tissue tumor and 3.05 was used in bone tumor by ROC curve. Results: There was a statistically significant difference in maxSUV between benign (n=11; maxSUV $3.4{\pm}3.2$) and malignant (n=12; maxSUV $14.8{\pm}12.2$) lesions in soft tissue tumor (p=0.001). Between benign bone tumor (n=9; maxSUV $5.4{\pm}4.0$) and malignant bone tumor (n=14; maxSUV $7.3{\pm}3.2$), there was not a significant difference in maxSUV. The sensitivity and specificity for differentiating malignant from benign soft tissue tumor was 83% and 91%, respectively. There were four false positive malignant bone tumor cases to include fibrous dysplasia, Langerhans-cell histiocytosis (n=2) and osteoid osteoma. Also, one false positive case of malignant soft tissue tumor was nodular fasciitis. Conclusion: The maxSUV was useful for differentiation of benign from malignant lesion in primary soft tissue tumors. In bone tumor, the low maxSUV correlated well with benign lesions but high maxSUV did not always mean malignancy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.406-413
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• 2019

The purpose of this research was to analyze the effect of different sowing times on the flowering and maturing of major soybean cultivars by varying day length and temperature in the central plain region. The average of growth period and cumulative temperature in five test cultivars by sowing times were 121 days and 2,972℃ on June 1, respectively and gradually decreased to 85 days, 2,042℃, respectively on July 20. Analysis of the flowering response according to the sowing times showed that flowering was greatly influenced by the decrease of photoperiod until the sowing on July 10, and the minimum number of days for flowering were 27 days, 36 days, respectively in early and mid-rate maturing type in the central plain region. Daepung 2 is classified to the same ecotype with Daewonkong, the total number of growing days was not different between two cultivars, but ripening period (R2-R6) was longer by 5 days and yield was higher by 11% in Daepung 2. The maturity rate was also high and safe enough to maintain more than 90% through the entire sowing times. This ecological characteristic can be usefully applied as a section index for breeding environmental stress resistant and high yielding soybean varieties. The yield of 4 domestic cultivars (except TI196944) sowing on July 20 were 85~92% levels compared to sowing on June 20.

• Journal of Soil and Groundwater Environment
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• v.6 no.3
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• pp.53-59
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• 2001

There is a lot of method to manage the insanitary landfill but vertical cutoff walls have been widespreadly used and were installed into the subsurface to act as a barrier to horizontal groundwater flow, The stabilized material such as specialized cement or mixed soil with additives has been generally applied for the materials of the deep soil mixing barrier in korea. The amount of the stabilized material is dependent on the field conditions, because the mixing ratio of the material and the field soil should achieve a requirement in the coefficient of permeability, lower than 1.0$\times$$10^{7}$cm/sec. This study determined the quantity and optimized function ratio of the stabilized material in the formation process of the mixed barrier that was added with stabilized material on the field soil classified into SW-SC under USCS (Unified Soil Classification System). After that the fly ash and lime were selected as an additives an that could improve the function of the stabilized material and then the method to improve the functional progress in the usage of putting into the stabilized material as an appropriate ratio was studied and reviewed. The author used the flexible-wall permeameter for measuring the permeability and unconfined compressive strength tester for compressive strength, and in the view of environmental engineering the absorption test of heavy metals and leaching test regulated by Korean Waste Management Act were performed. As the results, the suitable mixing ratio of the stabilized material in the deep soil mixing barrier was determined as 13 percent. To make workability easy, the ratio of stabilized material and water was proven to be 1 : 1.5. With the results, the range of the portion of the additives(fly ash : lime= 70 : 30) was proven to be 20-40% for improving the function of the stabilized material, lowering of permeability. In heavy metal absorption assessment of the mixing barrier system with the additives, the result of heavy metal absorption was proved to be almost same with the case of the original stabilized material; high removal efficiency of heavy metals. In addition, the leaching concentration of heavy metals from the leaching test for the environmental hazard assessment showed lower than the regulated criteria.

• The Korean Journal of Nuclear Medicine
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• v.34 no.4
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• pp.276-284
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• 2000

Purpose: We investigated the operative outcome after bypass surgery in patients selected using viability criteria on F-18 FDG PET. Materials and Methods: Rest-24hr delay redistribution imaging of Tl-201 SPECT and F-18 FDG PET were performed in 11 patients. Seven of these 11 patients (6 men, 1 woman) were evaluated to have viable myocardium by F-18 FDG PET. Changes in symptoms and left ventricular ejection fraction (LVEF) after operation were evaluated. Results: In seven of 11 patients, a significant amount of viable myocardium was found on F-18 FDG PET and Tl-201 SPECT. Severity of both chest pain and dyspnea improved markedly in all patients. Mean LVEF improved from 22% to 32%. Conclusion: F-18 FDG PET could be used to select the patients who will benefit from coronary artery bypass surgery.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.976-982
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• 1998

The effects of the glycoprotein (PAG) isolated from Pteridium aquilinum on the immune function was examined in mice. PAG was intraperitoneally administered into BALB/C mice for 14 days and the antibody forming ability to hen egg lysozyme (HEL) and the blastogenic responses of splenocytes were measured. PAG treatment significantly increased antibody formation to HEL in a dose-dependent manner. Blatogenesis of splenocytes in response to lipopolysaccharide (LPS, B-cell specific mitogen) or phytohemagglutinin (PHA, T-cell specific mitogen) was also increased after treatment with PAG, indicating that the PAG increases both humoral and cellular immunities. To examine whether the immune function of PAG was via a direct effect on the lymphocytes, splenocytes were isolated from BALB/C mice, exposed to various concentrations of PAG in vitro and the blastogenic responses were measured. In vitro exposure to PAG significantly increased blastogenesis of splenocytes to LPS up to $500{\;}{\mu}g/kg$, whereas the blastogenic response to PHA was not altered by PAG treatment. To identify the fraction responsible for the increase in the immune function, the effect of periodate digest, pronase digest or purified polysaccharide on the antibody production to HEL was examined. Crude protein fraction of PAG significantly increased the antibody formation to HEL. On the other hand, both crude and purified polysaccharide fractions did not have any effects on the antibody production ability. These data indicated that 1) PAG increased both humoral and cellular immune functions, 2) the increase in humoral immunity was probably via a direct action of PAG on lymphocytes and 3) the protein portion of PAG was responsible for the increase in humoral immunity.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.2
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• pp.66-73
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• 2019

The Royal Tomb of the Joseon Dynasty, which was listed as a UNESCO World Heritage site in 2009, is a cultural resource recognized for its 'outstanding universal value' around the world. The royal tomb of Joseon has been managed with an emphasis on the preservation of cultural assets since it was designated as a historical site in the 1970s, but it has received many visitors as a valuable historical and cultural resource and haven that connects the past and the present in today's bustling city. In order to investigate and analyze the current status of pavements in the royal palace in terms of quality and quantity, and to suggest the direction of improvement, this study conducted a complete survey of 53 royal palace viewing roads in 18 regions, and the results are as follows. First of all, problems are found in both the early Masato pavement of the creation, which was introduced with an emphasis on the preservation and protection of cultural assets, and the hardening pavement(KAP), which began to be used in the 1990s for the convenience of maintenance. In other words, the Masato pavement used to create a more environmentally friendly atmosphere of the Joseon royal tombs is showing a high percentage of use, but it lacks support for walking activities, such as the slippage of the pavement and water pooling during the rainy season or during the ice season. Also, hardening pavement introduced for convenience of maintenance, such as the movement of repair vehicles, is not functioning properly as it is damaged by physical deformation after construction. In addition, in awe zones such as parking lots, although the first image of the Joseon royal tombs is determined, the formation of the functional landscape centered on the carriageway does not harmonize with the traditional landscape, and, because of its lack of walking and environment-friendly features, there is a need for improvement, such as the experimental introduction of relevant pavement materials developed afterwards and continuous monitoring.

• Journal of Food Hygiene and Safety
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• v.38 no.2
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• pp.37-45
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• 2023

The surge in food delivery systems during the coronavirus 2019 pandemic necessitated this study of heavy metal migration from food contact materials (FCMs). A total of 104 samples of FCMs, comprising 51 polypropylene (PP), 21 polyethylene (PE), and 32 polystyrene (PS) samples of six different types of FCMs (containers, covers, table utensils, cups, pouches, and wrappers) used for food delivery distributed in Korea, were collected and investigated for migration of three heavy metals (Pb, Cd, and As) using inductively coupled plasma-mass spectrometry (ICP-MS) to determine whether they complied with Korea's Standards and Specifications for Utensils, Containers, and Packages. Acetic acid (4%, v/v) was used as the food simulant, and tests were performed at 100℃ (in harsh conditions) for 30 min. Linearity of Pb, Cd, and As showed acceptable results with a coefficient of determination (R²) value of 0.9999. Limit of detection (LOD) and limit of quantification (LOQ) of Pb, Cd, and As were 0.001, 0.001, and 0.001 ㎍/L and 0.002, 0.003, and 0.003 ㎍/L, respectively. Accuracy and precision results complied with the criteria presented in the European Commission Joint Research Centre guidelines. The average concentration of Pb, Cd, and As migration detected in a total of 104 samples was 0.009-0.260 ㎍/L, which was very low compared with the migration specification set in the Standards and Specifications for Utensils, Containers, and Packages. The maximum level of Pb corresponded to 0.23% of the migration limit. There were no samples exceeding the limit. Thus, this study confirmed that the heavy metal contents of FCMs used for delivery food distributed in Korea were safely managed. The data from this study represent an invaluable source for science-based safety management of hazardous heavy metals migrating from FCMs used in the food delivery industry.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.18 no.2
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• pp.1-20
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• 2023

The purpose of this study is to identify the unique entrepreneurial behavioral attributes of social enterprises that are distinct from for-profit enterprises at the organizational level, derive a social entrepreneurship model that reflects the unique characteristics of social enterprises as strategic decision-making and organizational behavioral tendencies. In order to effectively achieve the purpose of this study, previous studies were reviewed, and qualitative studies were conducted using the grounded theory method based on this. In this study, social entrepreneurship was identified as five sub-factors through a series of analysis processes, and 'Social value orientation; Innovativeness; Pro-activeness; Risk taking; Cooperation orientation' was newly proposed. It also proposed a new social entrepreneurship framework that integrates and explains the multidimensional model of social entrepreneurship by reviewing and connecting the relationships between each sub-factor of the research model. The 'social entrepreneurship framework' classified the social entrepreneurship model into 'pro-social motivation', 'pro-social behavior', and 'entrepreneurial behavior' attributes and explained them by linking them with each sub-factor that constitutes social entrepreneurship. The most remarkable difference between this study and previous studies is that it identified and added 'Cooperation orientation' as a sub-factor constituting social entrepreneurship from the organizational-level behavioral point of view. Through this study, 'Cooperation orientation' was identified as a major behavioral tendency for social enterprises to materialize pro-social motivation, strengthen the economic foundation of business activities, and improve the efficiency of business operations. 'Cooperation orientation' is a major behavioral tendency that strengthens the legitimacy of business activities between pro-social motivation and profit-seeking of social enterprises, improves the performance of social value creation activities, and overcomes the difficulties of resource constraints through cooperation with the outside and improves operational efficiency. In addition, it was confirmed that 'Cooperation orientation' is a major behavioral tendency of social enterprises that is manifested simultaneously in social value-oriented activities and entrepreneurial activities pursuing profit. The 'Cooperation orientation' newly identified in the study supplements the previous research, increases the explanatory power of the theory of social entrepreneurship, and provides the basis for theoretical expansion to subsequent researchers.

• Journal of Korean Neurosurgical Society
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• v.30 no.10
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• pp.1210-1219
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• 2001

Introduction : The purpose of this study was to analyze the safety, pullout strength and radiographic characteristics of unicortical and bicortical screws of cervical facet within cadaveric specimens and evaluate the influence of level of training on the positioning of these screws. Methods : Twenty-one cadavers, mean 78.9 years of age, underwent bilateral placement of 3.5mm AO lateral mass screw from C3-C6(n=168) using a slight variation of the Magerl technique. Intraoperative imaging was not used. The right side(unicortical) utilized only 14mm screws(effective length of 11mm) while on the left side to determine the length of the screw after the ventral cortex had been drilled. Three spine surgeons(attending, fellow, chief resident) with varying levels of spine training performed the procedure on seven cadavers each. All spines were harvested and lateral radiographs were taken. Individual cervical vertebrae were carefully dissected and then axial radiographs were taken. The screws were evaluated clinically and radiographically for their safety. Screws were graded clinically for their safety with respect to the spinal cord, facet joint, nerve root and vertebral artery. The grades consisted of the following categories : "satisfactory", "at risk" and "direct injury". Each screw was also graded according to its zone placement. Screw position was quantified by measuring a sagittal angle from the lateral radiograph and an axial angle from the axial radiograph. Pull-out force was determined for all screws using a material testing machine. Results : Dissection revealed that fifteen screws on the left side actually had only unicortical and not bicortical purchase as intended. The majority of screws(92.8%) were satisfactory in terms of safety. There were no injuries to the spinal cord. On the right side(unicortical), 98.9% of the screws were "satisfactory" and on the left side(bicortical) 68.1% were "satisfactory". There was a 5.8% incidence of direct arterial injury and a 17.4% incidence of direct nerve root injury with the bicortical screws. There were no "direct injuries" with the unicortical screws for the nerve root or vertebral artery. The unicortical screws had a 21.4% incidence of direct injury of the facet joint, while the bicortical screws had a 21.7% incidence. The majority of "direct injury" of bicortical screws were placed by the surgeon with the least experience. The performance of the resident surgeon was significantly different from the attending or fellow(p<0.05) in terms of safety of the nerve root and vertebral artery. The attending's performance was significantly better than the resident or fellow(p<0.05) in terms of safety of the facet joint. There was no relationship between the safety of a screw and its zone placement. The axial deviation angle measured $23.5{\pm}6.6$ degrees and $19.8{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The resident surgeon had a significantly lower angle than the attending or fellow(p<0.05). The sagittal angle measured $66.3{\pm}7.0$ degrees and $62.3{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The attending had a significantly lower sagittal angle than the fellow or resident(p<0.05). Thirty-three screws that entered the facet joint were tested for pull-out strength but excluded from the data because they were not lateral mass screws per-se and had deviated substantially from the intended final trajectory. The mean pull-out force for all screws was $542.9{\pm}296.6N$. There was no statistically significant difference between the pull-out force for unicortical($519.9{\pm}286.9N$) and bicortical($565.2{\pm}306N$) screws. There was no significant difference in pull-out strengths with respect to zone placement. Conclusion : It is our belief that the risk associated with bicortical purchase mandates formal spine training if it is to be done safely and accurately. Unicortical screws are safer regardless of level of training. It is apparent that 14mm lateral mass screws placed in a supero-lateral trajectory in the adult cervical spine provide an equivalent strength with a much lower risk of injury than the longer bicortical screws placed in a similar orientation.

• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.441-447
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• 2007

Internal derangement of the temporomandibular joint(TMJ) is defined as an abnormal relationship of the articular disc to the condyle. Mandibular manipulation is one of the conservative treatments to be considered first to manage the patients with anterior disc displacement without reduction. Mandibular manipulation is used to increase articular mobility and to restore the displaced disc into an anatomically normal position. While Farrar's technique has been popularly used, Minagi et al., Mongini and Suarez introduced the manipulation technique conducted by the patients themselves. But there is no study on the efficacy of self-manipulation technique, comparing with conventional one. The aim of this study was to investigate the efficacy of the conventional and self-manipulation technique, which was modified to complement the previously described technique by Minagi et al., in the treatment of patients with anterior disc displacement without reduction. TMD patients, who visited Department of Oral Medicine of Seoul National University Dental Hospital from December, 2002 to November, 2004 and were diagnosed as anterior disc displacement without reduction by TMJ magnetic resonance imaging (MRI) were enrolled. Conservative treatments including physical therapy, exercise, behavioral therapy, stabilization splint therapy, and manipulation therapy were done to every single patient until the symptomsimproved enough to discharge the patient. The charts were reviewed retrospectively according to the type of manipulation. In the results, patients whose maximum mouth opening was more than 40 mm was higher in the self-manipulation group(69.9%) than in the conventional manipulation group(42.9%). But difference between two groups was not significant. According to the fact that we decided to discharge the patients whentheir mouth opening increased to more than 40 mm and subjective symptoms such as pain and discomfort were improved as well, treatment period of discharged patients was significantly shorter in the self-manipulation group($29.2{\pm}12.3$ weeks) than in the conventional manipulation group ($61.0{\pm}38.0$ weeks) (p<0.01). In conclusion, in the treatment of TMD patients with anterior disc displacement without reduction, the self-manipulation technique which is performed by patients themselves is an effective treatment modality for increasing the range of mouth opening and shortening the total treatment period.