• Journal of the Korean Magnetic Resonance Society
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• v.5 no.1
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• pp.1-12
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• 2001

ZSM-5 gallosilicate molecular sieves was synthesized and cupric ion was ion-exchanged into the gallosilicate. The locations of Cu(ll) species in the framework and their interactions with various adsorbates were characterized by combined electron spin resonance(ESR) and electron spin echo modulation(ESEM) methods. It was found that in a fresh hydrated material, Cu(II) is octahedrally coordinated to six water molecules. This species is located in the channel intersections of two sinusoidal channels and rotates rapidly at room temperature. Evacuation removes some of these water molecules, leaving the Cu(II) coordinated to less water molecules and anchored to of oxygens in the channel wall. Dehydration produces two Cu(II) species, both of which are located in sites inaccessible to oxygen as evidenced by non-broadening of its ESR lines by oxygen. Adsorption of adsorbate molecules such as water, alcohols, ammonia, acetonitrile and ethylene on dehydrated CuNaH-ZSM-5 gallosilicate materials causes changes in the ESR spectrum of Cu(II), indicating the migration of Cu(II) into main channels to form complexes with these adsorbates there. Cu(II) forms a complex with two molecules of methanol, ethanol and propanol, respectively as evidenced by ESR parameters and ESEM data. Cu(II) also forms a square planar complex with four molecules of ammonia, based on the resolved nitrogen superhyperfine interactions and their ESEM parameters. Cu(II) forms a complex with two molecules of acetonitrile based on the ESR parameters and ESEM data. Interestingly, however, only part of Cu(II) interacts indirectly with one molecule of nonpolar ethylene based on ESR and ESEM analyses.

• Archives of Craniofacial Surgery
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• v.18 no.2
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• pp.137-140
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• 2017

Alloplastic materials used for orbital fracture reconstruction can induce complications, such as infection, migration, extrusion, intraorbital hemorrhage, and residual diplopia. Silicone is one of the alloplastic materials that has been widely used for decades. The author reports a rare case of spontaneous extrusion of a silicone implant that was used for orbital fracture reconstruction 30 years earlier. A 50-year-old man was admitted to the emergency room for an exposed substance in the lower eyelid area of the left eye, which began as a palpable hard nodule a week earlier. The exposed material was considered to be implant used for previous surgery. Under general anesthesia, the implant and parts of the fibrous capsule tissue were removed. Several factors hinder the diagnosis of implant extrusions that occur a long period after the surgery. So, surgeons must be aware that complications with implants can still arise several decades following orbital fracture reconstruction, even without specific causes.

• Geomechanics and Engineering
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• v.37 no.6
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• pp.599-614
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• 2024

To evaluate the safety status of deteriorated segments in a submarine shield tunnel during its service life, a seepage model was established based on a cross-sea shield tunnel project. This model was used to study the migration patterns of erosive ions within the shield segments. Based on these laws, the degree of deterioration of the segments was determined. Using the derived analytical solution, the internal forces within the segments were calculated. Lastly, by applying the formula for calculating safety factors, the variation trends in the safety factors of segments with different degrees of deterioration were obtained. The findings demonstrate that corrosive seawater presents the evolution characteristics of continuous seepage from the outside to the inside of the tunnel. The nearby seepage field shows locally concentrated characteristics when there is leakage at the joint, which causes the seepage field's depth and scope to significantly increase. The chlorine ion content decreases gradually with the increase of the distance from the outer surface of the tunnel. The penetration of erosion ions in the segment is facilitated by the presence of water pressure. The ion content of the entire ring segment lining structure is related in the following order: vault < haunch < springing. The difference in the segment's rate of increase in chlorine ion content decreases as service time increases. Based on the analytical solution calculation, the segment's safety factor drops more when the joint leaks than when its intact, and the change rate between the two states exhibits a general downward trend. The safety factor shows a similar change rule at different water depths and continuously decreases at the same segment position as the water depth increases. The three phases of "sudden drop-rise-stability" are represented by a "spoon-shaped" change rule on the safety factor's change curve. The issue of the poor applicability of indicators in earlier studies is resolved by the analytical solution, which only requires determining the loss degree of the segment lining's effective bearing thickness to calculate the safety factor of any cross-section of the shield tunnel. The analytical solution's computation results, however, have some safety margins and are cautious. The process of establishing the evaluation model indicates that the secondary lining made of molded concrete can also have its safety status assessed using the analytical solution. It is very important for the safe operation of the tunnel and the safety of people's property and has a wide range of applications.

• Cross-Cultural Studies
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• v.26
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• pp.123-144
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• 2012

In the modern society in which globalization and localization proceed simultaneously, diversified and rapid migration of diaspora makes a new from of boundary off the frame of the state and the nation. This new border accompanies cultural change and racial mixture; retains ethnic conflict, the gap between rich and poor, alienation and discrimination, as well as power conflict; and extends its influence. Nowadays, the countries all over the world including Korea face problem of Diaspora in numerous forms. And each country takes an approach to the problem of the diaspora in the aspects of their society, culture and political technology. This implies that most countries, without understanding the new form of border which is alive and dynamic, define and conceptualize the diaspora in the frame of one state and one nation to carry forward the policies accordingly, resulting in inequal, incomplete and awkward homogenization. This study aimed to explore the identity of the diaspora, the core for the problem solving. Of course, studies about the identity of the diaspora have been continued until today and many great outcomes have been achieved. Nevertheless, this study aimed to explore the identity of the diaspora and the national policies which have a close interrelationship with it. It is because the study ultimately aimed to highlight the interrelationship between the destination countries, Russia and China, and the diaspora, through the definition and the classification of Russian diaspora and Chinese diaspora and the analysis of the national policies about that. However, the intention was not to distinguish superiority through the comparison of the polices about the diaspora between two countries, but to focus on the diversity of the identity of the diaspora through defining each different diaspora and paralleling the policies. Second, the reason for looking into the diaspora policies of these two countries is because it is judged the changes in the diaspora policies of each country is one of the active factors for the changes in the identify of the diaspora of each country and it is the basic research for the study on the identity of the diaspora. New migration of diaspora changes the identity of the state, and the state makes the policies and enforce the policies, resulting in the influence on the diaspora. This interaction acts as the growth factor for the new boundary. The causes of Russian diaspora and Chinese diaspora show apparent 'differences'. In parallel with this, the policies about the diaspora in Russia and China arouse 'differences' to the diaspora. The variation of the identity of the diaspora made by these differences will suggest other viewpoints on the diaspora, and these viewpoints will become the foundation for solving the problem of the diaspora in the present times.

• Journal of Veterinary Clinics
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• v.31 no.1
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• pp.11-14
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• 2014

This is a retrospective study describing postoperative complication encountered with surgery performed in dogs with medial patellar luxation (MPL). During the 4-year period, 77 operations had been performed in 66 dogs for correction of MPL. The patients were surgically treated with medial soft tissue release, lateral soft tissue tightening, trochlear block recession, and/or tibial tuberosity transposition (TTT). Their prognoses were periodically evaluated for 6 months postoperatively. The failure rate was higher in revision surgery than in the first surgery, and the most common postoperative complication was migration of the tibial tuberosity fragment. The causes for the migration of the tibial tuberosity fragment were identified as the downward insertion of a surgical pin, the eccentric position of an inserted pin in the tibial tuberosity fragment, and blunt angle formation of the tibial tuberosity. It is suggested that the appropriate methods for TTT could minimize complications and lead to a good prognosis.

• Journal of the Korean Geotechnical Society
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• v.37 no.12
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• pp.47-56
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• 2021

The cryosuction (negative pore pressure) in freezing soils causes groundwater migration from the frozen fringe to freezing front for ice lens formation. Frost heave and heaving pressure by ice lens cause damage to ground infrastructure. In order to prevent damage by the frost heave, various frost susceptibility criteria have been proposed. The SP (Segregation Potential) is the most widely used classification criterion for frost susceptibility in cold regions. The expansion of the ice lens by the migration of the groundwater is a key role in frost heave mechanism, and thus it is necessary to evaluate the hydraulic conductivity. In this paper, soil mixtures of coarse-fines (sand-silt) were prepared in various weight fractions and used for frost heave and column permeability test. For each case, the SP and the hydraulic conductivity were derived and correlations were analyzed. As a results, the transition threshold of the SP and the hydraulic conductivity were shown at 20% and 50% of the silt weight fraction, respectively. Although there are difference between these transition thresholds, these two coefficients show a specific correlation. In the future, additional study should be conducted for detailed analysis of the threshold transition values between SP and hydraulic conductivity.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.5
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• pp.60-69
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• 2008

The principal reasons for applying a pigment coating to paper are to improve appearance and printability. The pigment coating provides a surface that is more uniform and more receptive to printing ink than are the uncoated fibers and, in turn, both facilitates the printing process and enhances the graphic reproduction. The improvement in print quality is readily apparent, especially in image areas or when multiple colors are involved. Although pigment coating of paper is to improve the printability, coated paper is not completely free from printing defects. Actually there are a number printing defects that are observed only with the coated papers. Among the printing defects that are commonly observed for coated papers, print mottle during multi-color offset printing is one of the most concerned defects, and it appears not only on solid tone area but also half dot print area. There are four main causes of print mottle ranging from printing inks, dampening solution, paper, and printing press or its operation. These indicates that almost every factors associated with lithographic printing can cause print mottle. Among these variation of paper quality influences most significantly on print mottle problems in multicolor offset printing, and this indicates that paper is most often to be blamed for its product deficiency as far as print mottle problems are concerned. Furthermore, most of the print mottle problems associated with paper is observed when coated papers are printed. Uncoated papers rarely show mottling problems. This indicates that print mottle is the most serious quality problems of coated paper products. Overcoming the print mottle is becoming more difficult because the operating speeds of coating and printing machines are increasing, coating weights are decreasing, and the demands on high-quality printing are increasing. Print mottle in offset printing is caused by (a) nonuniform back trap of ink caused by a nonuniform rate of ink drying, referred as "back trap mottle, and (b) nonuniform absorption of the dampening solution. Furthermore, both forms of print mottle have some relationship to the structure of the coated layer. The surest way of eliminating ink mottling is to eliminate unevenness in the base paper. Coating solutions, often easier to put into practice, should, however, be considered. In this paper the principal factors influencing print mottle of coated papers will be discussed. Especially the importance of base paper roughness, binder migration, even consolidation of coating layers, control of the drying rate, types of binders, etc. will be described.

• The Journal of Korean Society of Virology
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• v.29 no.2
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• pp.75-86
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• 1999

Rotaviruses belong to Reoviridae causes diarrhea in human beings as well as domestic animals. This study was conducted to see what type of human rotaviruses are distributed in Seoul and Kyung-gi province. Twenty two of 81 patients showed rotavirus positive with diagnostic kit and RNA electropherosis. We isolated all of rotaviruses from the patients. Electropherotypes of 22 isolates showed 4:2:3:2 pattern whereas those migration patterns were long type. All of those isolates belonged to group A. Twenty out of 22 isolates reacted with monoclonal antibodies specific to G1, P1A and subgroup II, whereas rest of them, A-29 and K-30 reacted with subgroup I specific monoclonal antibody. The nucleotide sequence of an isolate K-21 showed $98{\sim}100%$ and $90{\sim}96%$ homologies with those of Wa and KU strain, respectively.

• Korea journal of population studies
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• v.24 no.2
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• pp.207-234
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• 2001

Even though the number of Korean Americans has dramatically increased over the last 20 years, there have been very few studies that have examined the health of this population. This paper investigates the contemporary health status of Korean Americans in comparison to Koreans, employing mortality related health measures: life expectance, age-specific death rates, and leading cause of death. Overall, we find that Korean American adults enjoy longer life expectancy and lower age-specific death rates than do their Korean counterparts, suggesting superior health status of the former as compared to the latter. Comparison of leading causes of death indicates that Korean American adults (age of 25-64) are more likely to die from neoplasms than are their Korean counterparts, while Koreans show a dramatically higher probability of death from liver-related diseases than Korean Americans. When these two cause of death are regressed on various demographic and socioeconomic factors, the difference in prevalence of neoplasms between the two populations disappeared, while that of liver-related diseases remains unaffected. Based on the outcomes from this research, we suggest that Korean Americans are a self-selected group in terms of health and socioeconomic status, and they adopt healthy behaviors after immigration. This has resulted in the relatively superior health of Korean Americans as compared to Koreans.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1791-1795
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• 2013

Aims and Background: Prostate cancer is one of the most common malignant tumors in the male reproductive system, which causes the second most cancer deaths of males, and control of angiogenesis in prostate lesions is of obvious importance. This study assessed the effect of apogossypolone (ApoG2) on proliferation and apoptosis of human umbilical vein endothelial cells (HUVECs). Subjects and Methods: HUVECs were treated with different concentrations of ApoG2. The survival rate of HUVECs were determined by MTT assay. Utrastructural changes of HUVECs were assessed with transmission electron microscopy. Apoptosis in HUVECs was analyzed by flow cytometry and cell migration by Boyden chamber assay. Matrigel assays were used to quantify the development of tube-like networks. Results: ApoG2 significantly inhibited HUVEC growth even at 24 h (P<0.05). The inhibitory effect of ApoG2 is more obvious as the concentration and the culture time increased (P<0.05). These results indicate that ApoG2 inhibits the proliferation of HUVECs in a time- and concentration-dependent manner with increase of the apoptosis rate. Besides, ApoG2 reduced the formation of total pseudotubule length and network branches of HUVECs. Conclusions: The results suggest that ApoG2 inhibits angiogenesis of HUVECs by growth inhibition and apoptosis induction.