• Archives of Pharmacal Research
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• 제22권5호
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• pp.437-447
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• 1999

Type I diabetes, also known as insulin-dependent diabetes mellitus (IDDM) results from the destruction of insulin-producing pancreatic $\beta$ cells by a progressive $\beta$ cell-specific autoimmune process. The pathogenesis of autoimmune IDDM has been extensively studied for the past two decades using animal models such as the non-obese diabetic (NOD) mouse and the Bio-Breeding (BB) rat. However, the initial events that trigger the immune responses leading to the selective destruction of the $\beta$ cells are poorly understood. It is thought that $\beta$ cell auto-antigens are involved in the triggering of $\beta$ cell-specific autoimmunity. Among a dozen putative $\beta$ cell autoantigens, glutamic acid decarboxylase (GAD) has bee proposed as perhaps the strongest candidate in both humans and the NOD mouse. In the NOD mouse, GAD, as compared with other $\beta$ cell autoantigens, provokes the earliest T cell proliferative response. The suppression of GAD expression in the $\beta$ cells results in the prevention of autoimmune diabetes in NOD mice. In addition, the major populations of cells infiltrating the iselts during the early stage of insulitis in BB rats and NOD mice are macrophages and dendritic cells. The inactivation of macrophages in NOD mice results in the prevention of T cell mediated autoimmune diabetes. Macrophages are primary contributors to the creation of the immune environment conducive to the development and activation of $\beta$cell-specific Th1-type CD4+ T cells and CD8+ cytotoxic T cells that cause autoimmune diabetes in NOD mice. CD4+ and CD8+ T cells are both believed to be important for the destruction of $\beta$ cells. These cells, as final effectors, can kill the insulin-producing $\beta$ cells by the induction of apoptosis. In addition, CD8+ cytotoxic T cells release granzyme and cytolysin (perforin), which are also toxic to $\beta$ cells. In this way, macrophages, CD4+ T cells and CD8+ T cells act synergistically to kill the $\beta$ cells in conjunction with $\beta$ cell autoantigens and MHC class I and II antigens, resulting in the onset of autoimmune type I diabetes.

• The Korean Journal of Nuclear Medicine
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• 제4권2호
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• pp.55-66
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• 1970

Reappraisal measurements of apparent half survival time of red cell by $^{51}Cr$ method was made and effects of blood-letting over red cell survival were observed. The study was performed on 53 normal male subjects under three different experimental conditions. 1. Group 1 Mean $^{51}Cr$ red cell half survival by ACD wash method was 29.7 days. $T\frac{1}{2}$ of Ascorbic acid method was 29.0 days in group with 100 mg dose and 29.1 days in group with 50 mg dose respectively. There was no difference between these two methods in regards to red cell half survival. No difference were noted in amount of ascorbic acid administered. 2. Group 2 As daily amount of blood loss is increased the shortening of red cell half survival was noted. Rapid phase was seen when blood loss ranged 10 to 25 ml per day, while slow phase noted when more loss amounted 25 ml or more daily. Thus, it was clear that there was more than an exponential relation between $T\frac{1}{2}$ and the amount of blood loss. 3. Group 3 $T\frac{1}{2}$ measured by cpm per whole blood was within normal range and $T\frac{1}{2}$ measured by cpm per red cell mass showed shortening tendency when compared with the former in the group measured after blood loss (from 25 ml daily up to 100 ml daily in 10 days). In the group with rather constant blood loss of 100 ml daily for 10 consecutive days revealed the significant difference in two measurements (P<0.01). 4. $T\frac{1}{2}$ in non-steady state When red cell production is increased compared with red cell destruction, $T\frac{1}{2}$ measured by cpm per red cell mass being shorter than that by cpm per whole blood. Shortening of $T\frac{1}{2}$ measured by cpm per whole blood is more prominent. if red cell destrction is enhanced and exceeds production. 5. It is clear that when expressing red cell destruction rate, $T\frac{1}{2}$ measured by cpm per whole blood is more adequate and production more consistent with cpm red cell mass. 6. $T\frac{1}{2}$ measured during blood-letting, when corrected by amount of blood loss, it remains normal. It is erroneous to use conventional equational when measuring $T\frac{1}{2}$ in non-steady. $T\frac{1}{2}$ measured by cpm per whole blood is considred more applicable in clinical evaluation.

• International Commerce and Information Review
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• 제13권3호
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• pp.353-375
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• 2011

Export control was first triggered by international export control system at US led COCOM in 1949. Numerous international efforts such as NPT in 1969, ZC in 1970, NSG in 1978, AG in 1985, MTCR in 1987, Wassenaar Arrangement(WA) establishment in 1995 with 1990's the fall of the Berlin Wall, have been made since. The concept of export control has been changed from weaponry and parts export control to preventing or blocking weaponry, respective goods and relevant technology from the hand of troubled regions and non-state actors as terrorist groups; and the new concept is described as Nonproliferation Control. Extent of control items is not only limited to conventional weaponry, but also includes weapons of mass destruction(WMD) and even dual use items which can be used for production, development, usage or storage. Control items include all items defined by NSG, MTCR, AG, WA, and CMC-Opec. The 9.11 terror had a strong influence on international society. Effort to prevent WMD proliferation has now become the most important issue for international security. This study aims to suggest improvement points for nonproliferation law and its effective implementation, based on problem and limitation identification along with analysis of nonproliferation law and implementation examples by type. Furthermore for the purpose of national and global security, export control system on strategic items which are considered to be a key issue in South and North Korea relationship needs to be effectively managed. Recently, North Korea's missile and nuclear tests have been criticized globally; and the global society including respective countries as China and South Korea is striving to urge export control in line with the UN resolution.

• Journal of the Korean Chemical Society
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• 제58권6호
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• pp.590-599
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• 2014

Environmental education, effectively performed at school, is very important to solve the environmental problems. Moreover the survey for teacher's perception is essential. The purpose of the study was to investigate the perception of environmental problems of middle school teachers in Pusan. The survey was done twice in 2007 and 2012, and based on the time intervals, careers, and major of the teachers. 200 teachers were chosen in 2007 and 300 teachers in 2012. How many environmental problems occurred during this time period affected the 471 teachers' perception was investigated and analyzed. The results are as follows. First, the perception difference of environmental problems was meaningful between two time intervals (p<.01). Especially, the perception of modern environmental problems and carbon emission showed considerable increase in both science and non-science major teachers. This may be caused by the climate change and the severity of lifestyles of indiscriminate consumerism. Second, the perception difference of environmental problems by careers was also meaningful (p<.01). Overall, the perception was obvious on the aspects of modern environmental problems, carbon emission, destruction of ozone layers, nuclear wastes, environmental hormones, and red tides. Teachers, having more careers irrespective of their teaching subjects, showed higher perception on the seriousness of environmental pollution, the necessity of environmental conservation, and the importance of health. Third, the perception of environmental problems between science and non-science major teachers was meaningful (p<.01). Particularly, the perception in the broad environmental problems was distinctive between them.

• Journal of Animal Science and Technology
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• 제46권5호
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• pp.871-878
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• 2004

Pulsed electric fields(PEF) technology is one of the latest nonthermal methods of food processing for obtaining safe and minimally processed foods. This technology can be effectively explored for obtaining safe food with minimum effect on nutritional, flavor, rheological and sensory qualities of food products. The process involves the application of high voltage(typically 20 ${\sim}$ 80 kv/cm) to foods placed between two electrodes. The mode of inactivation of microorganism; by PEP processing has been postulated in term; of electric breakdown and electroporation. The extent of destruction of microorganisms in PEF processing depends mainly on the electric field strength of the pulses and treatment time. For each cell types, a specific critical electric field strength and specific critical treatment time are required depending on the cell characteristics and the type and strength of the medium where they have been present. The effect also depends on the types of microorganisms and their phase of growth. A careful combination of processing parameters has to be selected for effective processing. The potential applications of PEF technology are numerous ranging from biotechnology to food preservation. With respect to food processing, it has already been established that, the technology is non-thermal in nature, economical and energy efficient, besides providing minimally processed foods. This article gives a brief overview of this technology for food processing applications.

• Journal of Periodontal and Implant Science
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• 제25권3호
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• pp.614-622
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• 1995

Root caries is very frequently developed on exposed root surface after periodontal surgical treatment. In order to determine the anti-caries effect of Nd : YAG laser irradiation on periodontally exposed root surface, 40 mandibular molar teeth that had been extracted due to excessive periodontal destruction were used as the experimental teeth. All teeth were treated by the same procedure as conventional periodontal root treatment, ie thorough scaling, root planing and root conditioning with tetracycline HCl(100mg/ml, 5min.). Within middle one third of root, mesial half surface(20) or distal half surface(20) was randomly irradiated at various power of 1.0W, 2.0W, 3.0W and 4.0W for 60 seconds by non-contact(5mm) delivery of a pulsed Nd : YAG laser(EN.EL.EN060, Italy). The microhardness was measured by Vikers microhardness tester(Wilson, USA) at 2mm/second of jog speed under 100gm load. The difference of microhardness between irradiated side and non-irradiated side was statistically analyzed ANOVA and Duncan's method. Following results were obtained ; 1. The microhardness(Knoop hardness number) was significantly higher in laser irradiated surface than non-irradiated surface(p<0.05). 2. There was no significant difference in microhardness between experimental groups classified by different laser power(p>0.1). The results suggest that Nd : YAG laser irradiation on exposed root suface after periodontal therapy may inhibit the root caries development by enhancing surface microhardness.

• Journal of the Economic Geographical Society of Korea
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• 제13권3호
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• pp.312-334
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• 2010

This paper examines the process of Gyeongbu Highway construction from the standpoint of political economy, which was pursued by President Park Jeong-Hee in the 1960s, focusing on the politics of mobility and demarcation implied in it. As results of examination, it can be argued that Gyeongbu Highway was seen as a powerful element to promote a socio-spatial integration of population and hence to enforce an authoritative political power of the Park regime through creation of mobility; that it has had an strong impact on changing the physical landscape of national space and the spatio-temporal rhythm of everyday life by extending the 'machine space' as a non-place; that it has provided a physical infrastructure on which the period of capital circulation could be reduced through its effect of space-time compression. But Gyeongbu Highway has led serious problems such as uneven regional development, expansion of non-place or alienated place, ecological destruction and pollution. In conclusion, a sustainable politics is suggested to overcome this kind of 'tragedy of highway' and to develop the highway as a true way of political and spatial balance and integration.

• The Journal of the Acoustical Society of Korea
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• 제18권7호
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• pp.56-66
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• 1999

Thermoacoustic oscillation is a significant problem in cylindrical-type combustors such as common internal combustion engines, industrial furnaces, gas turbine, etc. This kind of low frequency oscillation can lead to serious consequences such as destruction of the combustor and production of strong noise. The accurate numerical simulation of thermoacoustic phenomena is a complex and challenging problem, especially when considering the chemical reaction of mixtures. As with other simulations of aerodynamics and aeroacoustics, the direct computation of thermoacoustic phenomena requires that Navier-Stokes equations be solved using accurate numerical differentiation and time-marching schemes, with non-reflecting boundary conditions. The numerical approach used here aims at qualitative analysis and efficient prediction of those problems, not at the development of an accurate scheme. The numerical prediction developed in this work is shown to be reasonably matched with experimental result.

• The Bulletin of The Korean Astronomical Society
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• 제40권2호
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• pp.34.3-35
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• 2015

Recent high-resolution infrared space missions have revealed supernova remnants (SNRs) of diverse morphology in far infrared (FIR), often very different from their X-ray appearance. This suggests that the FIR emission from SNRs could be of different origins. For a sample of 20 Galactic SNRs, we examine the correlation between their FIR and X-ray properties and explore the origin of the FIR emission. We find that the SNRs with very different FIR and X-ray morphology have relatively large infrared-to-X-ray (IRX) flux ratios. We argue that the FIR emission in these SNRs is likely mainly from dust grains radiatively-heated by shock radiation. For SNRs with similar IR and X-ray morphology, the FIR emission of which is probably mostly from dust grains collisionally heated by hot plasma, we compare their IRX flux ratios with theoretical ratios from a model incorporating time-dependent dust destruction and non-equilibrium ionization cooling behind SNR shock, and discuss the implications of our result.

• Journal of the Korean Society of Costume
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• 제58권8호
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• pp.106-119
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• 2008

This study explores grotesque characteristics that were raised as the Aesthetics of the Ugly and how it was featured in Alexander McQueen's arts. In a methodological approach, the study attempted the analysis of historical literature that was published both nationally and internationally, along with justifiable investigation using fashion/collection magazines such as Vogue, Gap and Internet search. The scope of this study ranges from 1996's Haute Couture and Pret-a-porter collection pieces modern, to date The results of this study are summarized as follows: The first grotesque characteristic present throughout Alexander Mcqueen's arts is that it featured horrifying images or evil motives with pointy heads or horns, dark colored dresses, silver accessories, Dracula, witches, skulls, soldiers of evil, death and sickness. Second, aversion was realistically portrayed by frightening objects, extreme intimacy and motives that signify death and closely relative to cruelty to human bodies. It also became visible with physical destruction of the bodies and dissecting of internal organs, etc. Thirdly, its expression of humor is out of common sense with distorted human bodies by intentionally overemphasizing certain portion of the clothes or body parts. It also featured strangely deformed bodies by ignoring the typical shapes of clothes, vague definition of gender and using of unusual objects. Forth, half-man and half-beast images are portrayed using various types of bird species or animals to Identify disparity. It further defined this image in the form of non-human cyborg by incorporating technology.