• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.1
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• pp.27-35
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• 2014

The headspace solid-phase microextraction (HS-SPME) followed by gas chromatography/mass spectrometry procedure has been developed for the simultaneous determination of petroleum aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) and polycyclic aromatic hydrocarbons (PAHs) in seawater. The advantages of SPME compared to traditional methods of sample preparation are ease of operation, reuse of fiber, portable system, minimal contamination and loss of the sample during transport and storage. SPME fiber, extraction time, temperature, stirring speed, and GC desorption time were key extraction parameters considered in this study. Among three kinds of SPME fibers, i.e., PDMS ($100{\mu}m$), CAR/PDMS ($75{\mu}m$), and PDMS/DVB ($65{\mu}m$), a $65{\mu}m$ PDMS/DVB fiber showed the most optimal extraction efficiencies covering molecular weight ranging from 78 to 202. Other extraction parameters were set up using $65{\mu}m$ PDMS/DVB. The final optimized extraction conditions were extraction time (60 min), extraction temperature (50), stirring speed (750 rpm) and GC desorption time (3 min). When applied to artificially contaminated seawater like water accommodated fraction, our optimized HS-SPME-GC/MS showed comparable performances with other conventional method. The proposed protocol can be an attractive alternative to analysis of BTEX and PAHs in seawater.

• (The)Study of the Eastern Classic
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• no.55
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• pp.115-145
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• 2014

In this paper, the transition of the status of Chinese novels and the change of the knowledge field in the modern times from the end of 19th century to the early 20th century, the transition period between the tradition and the modern times, have been investigated based on Liang Qichao's assertion of the Revolution of the Novel World. How the traditional novels have been evaluated, how modern novels enlightened a people and changed the political society, and what role novels acted in the change of the knowledge field are investigated. Especially I looked into the accumulations of knowledge and changes inside China which were overlooked in the previous researches which focused on the inflow of the Western culture and its impact on Chinese culture. Firstly the evaluation and classification of the traditional novels are considered. Because the transition of the status of novels and the classification method of the catalog of books are tightly coupled with the change of academic ideologies. Later I tried to understand novels as a way of thinking the modern times with a discussion on the changes of modern knowledge society and the consideration of Liang Qichao's Revolution of the Novel World in the two viewpoints, i.e. the relationship between novels and political society, and novels and the style of writing. Liang Qichao raised novels to the topmost position of literature. He pushed the traditional poetry off the top position and replaced it with popular novels. As the outside impact of Western culture made Chinese novels a tool for enlightening the ignorant people and the medium of propagating the knowledge, the status of novels was elevated to the highest level which novels had never reached in the past. With the limitation that the valuation was not based on the aesthetic appreciation of art but based on the value for politics and society, novel was a discourse of life and death to save the country and a container of knowledge to rebuild the people's mind and convert the crisis of the national ruin.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.22-47
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• 2014

This study was to understand the basic principles of the East Asian wooden structure system research and analysis. The Korea and China ancient architecture internal structure research that the combination of girders and crossbeams position. The ancient wooden structures of eastern Asian countries, Korea and China are not much different from each other in the principles of the wooden architecture structure, combining pillars, purlins and crossbeams. However, it seems that age-division, local-division, national-division differs in detail techniques. China ancient wooden structures combination of purlin and crossbeam, and So-seul Timber(Chinese name: Chashou叉手, Tuojiao 托脚) seems to show differences according to the age of the fulcrum position, detailed approach is also different according to various historical dynasty. Before in the 15th century, Purlin and Crossbeam are coupled to each other, but since the 15th century, seems to have developed a technique combined with each other Girder and Crossbeam and to prevent buckling of the Crossbeam cross-sectional area increased dramatically. For Tuojiao in China Tang-Wudai dynasty(A.D. 618~979), can see that saw the top position Girder and Tuojiao no direct coupling, can be seen as maintaining the safety of the material than the material of the inner wooden structures prevent buckling of the purlin. Korea ancient wooden structures of Goryeo dynasty(A.D. 918~1391), So-seul Timber(Chinese name Tuojiao) why do not to use the fashion? To use Purlin Lower backing material techniques to prevent buckling is a popular trend to stable can be thought of as a preferred way to maintain. I think that with universality beyond the local-division, national-division and the two countries since the 15th century of Korea and China ancient wooden structures detailed mechanism for the purlin buckling. In middle-late Chosen dynasty, The effect of Deotgeolyi- techniques and fleeting beams reduce the purlin buckling that reduces the load transmitted from purlin and crossbeam of how to reduce the load on the roof portion of the architecture fleeting beams used, which of craftsmanship of the Chosen Dynasty building can be referred to as another technique for preventing buckling purlin. This Korea and China ancient architecture purlin beam structure and material So-seul Timber study. Seems to be able to provide a basic research study to restore and designed the old wooden architectures.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.9 no.1
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• pp.9-16
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• 2023

Liposomes as drug delivery system have proved useful carrier for various disease, including cancer. In addition, perfluorocarbon cored microbubbles are utilized in conjunction with high-intensity focused-ultrasound (HIFU) to enable simultaneous diagnosis and treatment. However, microbubbles generally exhibit lower drug loading efficiency, so the need for the development of a novel liposome-based drug delivery material that can efficiently load and deliver drugs to targeted areas via HIFU. This study aims to develop a liposome-based drug delivery material by introducing a substance that can burst liposomes using ultrasound energy and confirm the ability to target tumors using PET imaging. Liposomes (Lipo-DOX, Lipo-DOX-Au, Lipo-DOX-Au-RGD) were synthesized with gold nanoparticles using an avidin-biotin bond, and doxorubicin was mounted inside by pH gradient method. The size distribution was measured by DLS, and encapsulation efficiency of doxorubicin was analyzed by UV-vis spectrometer. The target specificity and cytotoxicity of liposomes were assessed in vitro by glioblastoma U87mg cells to HIFU treatment and analyzed using CCK-8 assay, and fluorescence microscopy at 6-hour intervals for up to 24 hours. For the in vivo study, U87mg model mouse were injected intravenously with 1.48 MBq of ⁶⁴Cu-labeled Lipo-DOX-Au and Lipo-DOX-Au-RGD, and PET images were taken at 0, 2, 4, 8, and 24 hours. As a result, the size of liposomes was 108.3 ± 5.0 nm at Lipo-DOX-Au and 94.1 ± 12.2 nm at Lipo-DOX-Au-RGD, and it was observed that doxorubicin was mounted inside the liposome up to 52%. After 6 hours of HIFU treatment, the viability of U87mg cells treated with Lipo-DOX-Au decreased by around 20% compared to Lipo-DOX, and Lipo-DOX-Au-RGD had a higher uptake rate than Lipo-DOX. In vivo study using PET images, it was confirmed that ⁶⁴Cu-Lipo-DOX-Au-RGD was taken up into the tumor immediately after injection and maintained for up to 4 hours. In this study, drugs released from liposomes-gold nanoparticles via ultrasound and RGD targeting were confirmed by non-invasive imaging. In cell-level experiments, HIFU treatment of gold nanoparticle-coupled liposomes significantly decreased tumor survival, while RGD-liposomes exhibited high tumor targeting and rapid release in vivo imaging. It is expected that the combination of these models with ultrasound is served as an effective drug delivery material with therapeutic outcomes.

• Analytical Science and Technology
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• v.20 no.4
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• pp.308-314
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• 2007

The analytical method of HPLC with the radial-flow electrochemical cell (RFEC) has been developed to determine doxorubicin, epirubicin, nogalamycin, daunorubicin and idarubicin simultaneously by employing a reversed-phase chromatography. Anthracyclines were detected at -0.74 V vs. a Ag/AgCl (0.01 M NaCl) reference electrode, a potential of diffusion current plateau in the mobile phase. At a $V_f$ of 1.0 mL/min doxorubicin, epirubicin, daunorubicin and idarubicin appeared at a retention time ($t_r$) of 6.4 min, 7.4 min, 12.7 min and 18.4 min, respectively, while at a $V_f$ of 0.6 mL/min, doxorubicin, epirubicin, nogalamycin, daunorubicin and idarubicin appeared at a $t_r$ of 9.9 min, 11.5 min, 13.5 min, 19.6 min and 28.7 min, respectively. The linearity between each anthracycline injected ($2.40{\times}10^{-7}M{\sim}1.42{\times}10^{-5}M$) and peak area (charge) was excellent with the square of the correlation coefficient ($R^2$) higher than 0.999. The detection limits were $1.0{\times}10^{-8}M{\sim}1.5{\times}10^{-7}M$ for the five anthracyclines. Within-day precision for the five anthracyclines were in reasonable relative standard deviations less than 3 % ($1.00{\times}10^{-6}M{\sim}1.42{\times}10^{-5}M$) except the lower concentrations less than $0.7{\mu}M$. Solid phase extractions of $1.00{\times}10^{-5}M$ epirubicin, $0.48{\times}10^{-5}M$ nogalamycin and $1.52{\times}10^{-5}M$ daunorubicin from human serum with a $C_{18}$ cartridge resulted in 97 %, 100 % and 90 % of recoveries, respectively.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.171-193
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• 2018

LOD(Linked Open Data) cloud is a practical implementation of semantic web. We suggested a new method that provides identity links conveniently in LOD cloud. It also allows changes in LOD to be reflected to searching results without any omissions. LOD provides detail descriptions of entities to public in RDF triple form. RDF triple is composed of subject, predicates, and objects and presents detail description for an entity. Links in LOD cloud, named identity links, are realized by asserting entities of different RDF triples to be identical. Currently, the identity link is provided with creating a link triple explicitly in which associates its subject and object with source and target entities. Link triples are appended to LOD. With identity links, a knowledge achieves from an LOD can be expanded with different knowledge from different LODs. The goal of LOD cloud is providing opportunity of knowledge expansion to users. Appending link triples to LOD, however, has serious difficulties in discovering identity links between entities one by one notwithstanding the enormous scale of LOD. Newly added entities cannot be reflected to searching results until identity links heading for them are serialized and published to LOD cloud. Instead of creating enormous identity links, we propose LOD to prepare its own link policy. The link policy specifies a set of target LODs to link and constraints necessary to discover identity links to entities on target LODs. On searching, it becomes possible to access newly added entities and reflect them to searching results without any omissions by referencing the link policies. Link policy specifies a set of predicate pairs for discovering identity between associated entities in source and target LODs. For the link policy specification, we have suggested a set of vocabularies that conform to RDFS and OWL. Identity between entities is evaluated in accordance with a similarity of the source and the target entities' objects which have been associated with the predicates' pair in the link policy. We implemented a system "Change Acceptable In-Depth Searching System(CAIDS)". With CAIDS, user's searching request starts from depth_0 LOD, i.e. surface searching. Referencing the link policies of LODs, CAIDS proceeds in-depth searching, next LODs of next depths. To supplement identity links derived from the link policies, CAIDS uses explicit link triples as well. Following the identity links, CAIDS's in-depth searching progresses. Content of an entity obtained from depth_0 LOD expands with the contents of entities of other LODs which have been discovered to be identical to depth_0 LOD entity. Expanding content of depth_0 LOD entity without user's cognition of such other LODs is the implementation of knowledge expansion. It is the goal of LOD cloud. The more identity links in LOD cloud, the wider content expansions in LOD cloud. We have suggested a new way to create identity links abundantly and supply them to LOD cloud. Experiments on CAIDS performed against DBpedia LODs of Korea, France, Italy, Spain, and Portugal. They present that CAIDS provides appropriate expansion ratio and inclusion ratio as long as degree of similarity between source and target objects is 0.8 ~ 0.9. Expansion ratio, for each depth, depicts the ratio of the entities discovered at the depth to the entities of depth_0 LOD. For each depth, inclusion ratio illustrates the ratio of the entities discovered only with explicit links to the entities discovered only with link policies. In cases of similarity degrees with under 0.8, expansion becomes excessive and thus contents become distorted. Similarity degree of 0.8 ~ 0.9 provides appropriate amount of RDF triples searched as well. Experiments have evaluated confidence degree of contents which have been expanded in accordance with in-depth searching. Confidence degree of content is directly coupled with identity ratio of an entity, which means the degree of identity to the entity of depth_0 LOD. Identity ratio of an entity is obtained by multiplying source LOD's confidence and source entity's identity ratio. By tracing the identity links in advance, LOD's confidence is evaluated in accordance with the amount of identity links incoming to the entities in the LOD. While evaluating the identity ratio, concept of identity agreement, which means that multiple identity links head to a common entity, has been considered. With the identity agreement concept, experimental results present that identity ratio decreases as depth deepens, but rebounds as the depth deepens more. For each entity, as the number of identity links increases, identity ratio rebounds early and reaches at 1 finally. We found out that more than 8 identity links for each entity would lead users to give their confidence to the contents expanded. Link policy based in-depth searching method, we proposed, is expected to contribute to abundant identity links provisions to LOD cloud.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.375-387
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• 2012

The objective of this study is investigation of contamination levels and assessment of health risk effects of heavy metals in herbal pills. 31 Items and 93 samples were obtained for this investigation from major herbal medicine producing areas, herbal markets and on-line supermarkets from Jan to Jun in 2010. Inductively coupled plasma mass spectrometer method was conducted for the quantitative analysis of Pb, Cd and As. In addition, the mercury analyzer system was conducted for that of Hg without sample digestion. The average contents of heavy metals in samples were as follows : 0.87 mg/kg for Pb, 0.08 mg/kg for Cd, 2.87 mg/kg for As and 0.16 mg/kg for Hg, respectively. In addition, the average contents of heavy metals in different parts of plants, including cortex, fructus, herba, radix, seed, algae and others were 0.63 mg/kg, 3.94 mg/kg, 1.42 mg/kg, 1.05 mg/kg, 0.16 mg/kg, 22.31 mg/kg and 10.17 mg/kg, respectively. After the estimations of dietary exposure, the acceptable daily intake (ADI), the average daily dose (ADD), the provisional tolerable weekly intake (PTWI) and the relative hazard of heavy metals were evaluated. As the results, the relative hazards compared to PTWI in samples were below the recommended standard of JECFA as Pb 3.1%, Cd 0.9%, Hg 0.5%. Cancer risks through slope factor (SF) by Ministry of Environment Republic Korea and Environmental Protection Agency was $4.24{\times}10^{-7}$ for Pb and $3.38{\times}10^{-4}$ for As (assuming that the total arsenic content was equal to the inorganic arsenic). Based on our results, possible Pb-induced cancer risks in herbal pills according to parts used including cortex, fructus, herba, radix, seed, algae and others were $1.95{\times}10^{-7}$, $1.45{\times}10^{-6}$, $2.14{\times}10^{-7}$, $6.27{\times}10^{-7}$, $1.99{\times}10^{-8}$, $3.61{\times}10^{-7}$ and $9.64{\times}10^{-8}$, respectively. Possible As-induced cancer risks in herbal pills by parts used including cortex, fructus, herba, radix, seed, algae and others were $1.54{\times}10^{-5}$, $7.24{\times}10^{-5}$, $1.23{\times}10^{-4}$, $2.02{\times}10^{-5}$, $3.25{\times}10^{-6}$, $2.18{\times}10^{-3}$ and $5.67{\times}10^{-6}$ respectively. Taken together, these results indicate that the majority of samples except for some samples with relative high contents of heavy metals were safe.

• Journal of Food Hygiene and Safety
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• v.39 no.4
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• pp.322-334
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• 2024

This study investigated the content of heavy metals (Pb, Cd, As, and Hg) and SO₂ and conducted a risk assessment of 1,340 samples of 60 herbs used for food and medicine in Seoul between 2019 and 2023. The analysis was performed using inductively coupled plasma mass spectrometry (ICP-MS), a mercury analyzer, and the Monier-Williams method. The mean values and ranges of the heavy metals were as follows: Pb, 0.327 mg/kg (not detectable [ND]-36.933); Cd, 0.083 mg/kg (ND-1.700); As, 0.075 mg/kg (ND-2.200); and Hg, 0.004 mg/kg (ND-0.047). Pb exceeded the permissible limit of 36.933 mg/kg in one sample of Poria Sclerotium. Cd exceeded the permissible limit of 1.700 mg/kg and 0.650 mg/kg in the two samples of Chrysanthemi Zawadskii Herba. The mean and range of SO₂ was 0.75 mg/kg (ND-192.00), with two samples of Gastrodiae Rhizoma exceeding the permissible limit at 192.00 mg/kg and 42.00 mg/kg. Pb was highest in the perithecium (1.377 mg/kg), followed by Cd in the cortex (0.156 mg/kg) and caulis (0.144 mg/kg), As in leaves (0.149 mg/kg), and Hg in the herba (0.009 mg/kg) and leaves (0.009 mg/kg). SO₂ was the highest in the rhizomes (4.12 mg/kg). The Pb, Cd, and Hg levels did not differ significantly between the domestic, Chinese, and imported products; however, As and SO₂ levels were the highest in the Chinese products. As a result of the risk assessment, all the margins of exposure (MOE) values of Pb, except for Poria Sclerotium, were ≥1, indicating that most samples were safe. The hazard index (HI) for Cd, As, and Hg were <100%, indicating a safety level for food and medicine. In addition, the HI for SO₂ did not exceed 1 for any of the items, indicating safe levels.