• Korea journal of population studies
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• v.35 no.1
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• pp.101-130
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• 2012

This study examines mortality change in North Korea and its association with state production and welfare systems. Two main subjects are analyzed. The first theme is to examine the reliability of mortality related data released by North Korea government authorities. Examining inner consistencies among mortality related statistics and comparing with mortality trends in other socialist societies, the study finds that mortality rate was under estimated. Under-estimation of mortality by North Korean authorities is regarded to result not only from political purpose which aims to propagate the regime's superiority but also from enumeration errors of vital statistics based on the residence registration. The second theme is to estimate the change in mortality of North Korean people since the establishment of DPRK, correcting errors of mortality data. Mortality of North Korean people is estimated to have improved largely by the early 1970s, to have been sluggish hereafter, and finally to have increased during the economic hardship period between 1993 and 2008. While large people died during the food crisis in the late 1990s, however the population loss caused by mortality increase was not so great as the proposition of the huge starvation was expected. It is partly because population turbulence occurred not just by mortality increase, rather it has progressed in the joint effects of fertility decline and exodus of North Korean people for food. It is also due to North Korean people's voluntary activities of informal economy. It is also worth noting the high mortality rate of North Korean men. The high mortality of North Korean men is likely due to men's mobilization for long time in army and labor with high risk of accident and their life styles.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.7 no.3
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• pp.181-194
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• 2002

Parasitism is a one-sided relationship between two organisms in which one benefits at the expense of the other. Parasitic dinoflagellates, particularly species of Amoebophrya, have long been thought to be a potential biological agent for controlling harmful algal bloom(HAB). Amoebophrya infections have been reported for over 40 species representing more than 24 dinoflagellate genera including a few toxic species. Parasitic dinoflagellates Amoebophrya spp. have a relatively simple life cycle consisting of an infective dispersal stage (dinospore), an intracellular growth stage(trophont), and an extracellular reproductive stage(vermiform). Biology of dinospores such as infectivity, survival, and ability to successfully infect host cells differs among dinoflagellate host-parasite systems. There are growing reports that Amoebophrya spp.(previously, collectively known as Amoebophrya ceratii) exhibit the strong host specificity and would be a species complex composed of several host-specific taxa, based on the marked differences in host-parasite biology, cross infection, and molecular genetic data. Dinoflagellates become reproductively incompetent and are eventually killed by the parasite once infected. During the infection cycle of the parasite, the infected host exhibits ecophysiologically different patterns from those of uninfected host in various ways. Photosynthetic performance in autotrophic dinoflagellates can be significantly altered following infection by parasitic dinoflagellate Amoebophrya, with the magnitude of the effects over the infection cycle of the parasite depending on the site of infection. Parasitism by the parasitic dinoflagellate Amoebophrya could have significant impacts on host behavior such as diel vertical migration. Parasitic dinoflagellates may not only stimulate rapid cycling of dissolved organic materials and/or trace metals but also would repackage the relatively large sized host biomass into a number of smaller dinospores, thereby leading to better retention of host's material and energy within the microbial loop. To better understand the roles of parasites in plankton ecology and harmful algal dynamics, further research on a variety of dinoflagellate host-parasite systems is needed.

• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.55-62
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• 2006

Transverse cracks in continuously reinforced concrete pavement (CRCP) occur at early ages due to temperature and moisture variations. The width and spacing of transverse cracks have a significant effect on pavement performance such as load transfer efficiency and punchout development. Also, crack widths in CRCP depend on 'zero-stress temperature,' which is defined as a temperature where initial concrete stresses become zero, as well as drying shrinkage of concrete. For good long-term performance of CRCP, transverse cracks need to be kept tight. To keep the crack widths tight throughout the pavement life, zero-stress temperature must be as low as practically possible. Thus, temperature control at early ages is a key component In ensuring good CRCP performance. In this study, concrete temperatures were predicted using PavePro, a concrete temperature prediction program, for a CRCP construction project, and those values were compared with actual measured temperatures obtained from field testing. The cracks were also surveyed for 12 days after concrete placement. Findings from this study can be summarized as follows. First, the actual maximum temperatures are greater than the predicted maximum temperature in the ranges of 0.2 to 4.5$^{\circ}C$. For accurate temperature predictions, hydration properties of cementitious materials such as activation energy and adiabatic constants, should be evaluated and accurate values be obtained for use as input values. Second, within 24 hours of concrete placement, temperatures of concrete placed in the morning are higher than those placed in the afternoon, and the maximum concrete temperature occurred in the concrete placed at noon. Finally, from the 12 days of condition survey, it was noted that the rate of crack occurrence in the morning placed section was 25 percent greater than that in the afternoon placed section. Based on these findings, it is concluded that maximum concrete temperature has a significant effect on crack development, and boner concrete temperature control is needed to ensure adequate CRCP performance.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.432-445
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• 2000

The objective of this study was to determine the effects of various kinds of composts on the change of nutrition loss in upland soils. Field experiments were conducted in the loam and sandy loam soils, while the clay loam and sandy loam soils were used for laboratory experiments. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : The loss of nutrients in the form of cation and anion by run-off water increased with the increase of compost application rate. Compared with bare soils, maize cultivation decreased the nutrient loss by run-off from soils by 43% in anionic form and 32% in cationic form. Amount of cation loss were ordered $K^+$ > $Ca^{2+}$ > $Na^+$ > $Mg^{2+}$ > $NH_4{^+} $ and that of anion loss were ordered $SO_4{^{2-}}$ > $NO_3{^-}$ > $Cl^-$ > $PO_4{^{3-}}$. Nutrient loss of sand loam soil in the cation and anion by percolation water increased 1.7 times compared with loam soil. $NO_3{^-}-N$ contents in percolated water were high at the initial stage after compost application, and the amounts were higher in sandy loam soil than loam soil. The maize cultivation also decreased the $NO_3{^-}-N$ contents in percolated water by 82% in loam soil, and 58% in sand loam soil. Soil pH of composts determined by laboratory incubation test increased pH 6.1~6.8 application with poultry and cow manure compost but application with human excrement sludge decreased pH 4.5~4.7. Soil EC were increased initially composts application and decreased up to 2 weeks, thereafter kept a certain level. Nitrogen mineralization rates of composts determined by laboratory incubation test at $25^{\circ}C$ were 39~76% in sandy loam soil, and 16~48% in clay loam soil.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.416-431
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• 2000

The objective of this study was to determine the effects of various kinds of composts on the change of soil chemical properties in upland soils. Field experiments were conducted in the loam and sandy loam soils. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80Mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : The continuous application of human excrement sludge decreased soil pH up to 4.4~5.0, while other compost treatments increased soil pH compared with control plot. The EC increased initially and showed their maximum values at 20days after compost application, and then decreased up to 40 days, thereafter kept a certain level. The available phosphorous accumulated at 0~20cm depth in loam soil, and 0~50cm in sandy loam soil. Annual accumulation rates were 17% higher in sandy loam soil than loam soil. The more compost application rates and times, the higher base saturation percentage increased in upland soils. Four year's application at a rate of $80Mg\;ha^{-1}$ per year increased the base saturation percentage to 87~97% compared with 45% at control plot in the loam soil. While in sandy loam soil only three year's application of same rate increased the base saturation percentage to 81~92% compared with 30.4% at control plot. The average annual increasing rate of base saturation percentage at the same application rates of composts were higher in sandy loam soil by 2.0~3.7 times than in loam soil. The application of compost increased the exchangeable Ca, Mg, and K contents of soils by 2, 2~3, and 3~5 times, respectively, compared with the control. The contents of exchangeable cations were high in surface soil, and decreased with increase of soil depths. In the case of heavy metal content, there were no difference at the application of PMC and CMC but Ni, Fe, Zn, Cu was increased a little when the HES applied, and Ni and Cr was increased application with FISC.

• Applied Microscopy
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• v.40 no.2
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• pp.89-99
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• 2010

Fibroblasts are the most common cells in connective tissue and are responsible for the synthesis of extracellular matrix components. The fibrosis associated with chronic inflammation and injury may contribute to cholangiocarcinoma pathogenesis, particularly through an increase in extracellular matrix components, which participate in the regulation of bile duct differentiation during development. Mitochondria produce ATP through oxidative metabolism to provide energy to the cell under physiological conditions. Also, mitochondrial dysfunction and oxidative stress have been implicated in cellular senescence and aging. Alternations in mitochondrial structure and function are early events of programmed cell death or apoptosis and mitochondria appear to be a central regulator of apoptosis in most somatic cell. Clonorchis sinensis, one of the most important parasite of the human bile duct in East Asia, arouses epithelial hyperplasia and ductal fibrosis. Isolated fibroblast from the bile ducts of rats infected by C. sinensis showed increase of cytoplasmic process. In addition, decrease of cellular proliferation was observed in fibroblasts which was isolated from normal rat bile duct and then cultured in media containing C. sinensis excretory-secretory product. However, the effects of C. sinensis infection on the mitochondrial enzyme distribution is not clearly reported yet. Therefore, we investigated the structural change of C. sinensis infected bile duct and mitochondrial enzyme distribution of the cultured fibroblast isolated from the C. sinensis infected rat bile duct. As a result, C. sinensis infected SD rat bile ducts showed the features of chronic clonorchiasis, such as ductal connective and epithelial tissue dilatation, or ductal fibrosis. In addition, fibroblast in ductal connective tissue was damaged by physical effect of fibrotic tissue and chemical stimulation. Immunohistochemically detected mitochondrial electron transferase (ATPase, COXII, Porin) was decreased in C. sinensis infected rat bile duct and cultured fibroblast from infected rat bile duct. It can be hypothesized that the reason why number of electron transferase decrease in fibroblast isolated from the rat bile duct infected with C. sinensis is because dysfunction of electron transport system is occurred mitochondrial dysfunction, increase of ROS (reactive oxygen species) and apoptosis after chemical damage on the cell caused by C. sinensis infection. Overall, C. sinensis infection induces fibrotic change of ductal connective tissue, mutation of cellular metabolism in fibroblast and mitochondrial dysfunction. Consequently, ductal fibrosis inhibits fibroblast proliferation and decreases mitochondrial electron transferase on fibroblast cytoplasm. It was assumed that the structure of bile duct could not normalized and ductal fibrosis was maintained for a long period of time according to fibroblast metamorphosis and death induced by mitochondrial dysfunction.

• Journal of Mushroom
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• v.11 no.3
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• pp.131-136
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• 2013

The effects of fixed and variable relative humidity on fruiting body formation and characters of Pleurotus eryngii were investigated with normal and thinning treatment plots. In fixed relative humidity, as humidity was lower, period of harvest was longer as well as days for pinheading in the both of normal and thinning plots. In the normal plot, qualities of mushroom were 5.5, 5.8, and 6.3 and yield was 98.6 g per bottle for 90% relative humidity, it was best. In the thinning plot, qualities of mushroom were 7.7, 8.4, and 8.5 and yields were 102.1, 105.8, and 116.9 g at 70, 80, and 90% respectively. In variable relative humidity with a thinning plot, the yield of P. eryngii on condition I(>90% for 1 day ${\rightarrow}$ 85% until thinning(for about 11 days) ${\rightarrow}$ 80%) and III(>90% until pin-heading(about for a week) ${\rightarrow}$ 85% until thinning(about for 5 days) ${\rightarrow}$ 80%) were 85.5 and 87.8 g per bottle, and qualities were 7.8 and 8.0 respectively. For long shelf life and a cultural control of bacterial soft rot disease, the condition I will be more largely adopted by mushroom farmers.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.3
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• pp.149-159
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• 2018

The study is aimed at establishing basic data to identify the original forms of the garden in Unbo's House. Through interviews and related data comparison analysis the ideas and major events of the person involved in establishing a garden in Unbo's House. Also, derived the direct and indirect effects of these people on gardening. The results are as follows: First, Those directly related to garden in Unbo's House are representative figures of cultural heritage and traditional art in Korea. Based on their expertise and abundant experience in traditional spaces, they contributed greatly to the creation of Unbo's House as a traditional space. Unbo Kim, Gi-Chang who directly influenced Unbo's House gardening, which affected the site selection, location, and the installation of major garden plant plants and traditional landscaping facilities. Hyegok Choi, Soon-Woo recommended Wabon Kim, Dong-Hyun at the request of Kim Ki-Chang and was involved in the overall plan. Housing design, space design and design of major facilities such as pond were confirmed Wabon Kim Dong-Hyun. Second, Kim, Gi-Chang's wife Jeong, Rae-Hyun, who motived to construct a garden. Nosan Lee, Eun-Sang and Korean artist Lee, Seok-Ho were created a signboard and board of the Pillar to encourage simple life in paintings. The themes of the article motived image as creative. In addition, Kim, Hyeong-Sik and Kim, Wan who son of Unbo, has been with Unbo for a long time, watching and influencing garden changes in Unbo's House. Third, The main factors that influenced the garden by character are as follows. Unbo Kim, Ki-Chang had a thorough record-setting spirit and his longing for his mother and wife affected the selection of the site and setting the direction of the garden. His art world with the symbolic emphasis of traditional landscapes, including traditional facilities, and especially plant materials. Choi, Sun-Woo reflected his traditional consciousness and experience in the construction of Unbo's House. Kim, Dong-Hyun applied the basic framework of a traditional building based on Yeonkyongdang hall in Changdeokgung palace. He also reflected on the traditional landscaping design the facilities of ponds acquired through excavation of Donggung Palace and Wolji Pond, Gyeongju. Nosan Lee, Eun-Sang and Lee, Seok-Ho completed their unique place in Unbo's House. Kim, Hyung-Sik was involved in the process of changing, while Kim Wan ran the Unbo's House which he inherited from Kim, Ki-Chang.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6099-6111
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• 2015

This study was a systematic review and meta-analysis comparing the effects of aquatic exercise and land-based exercise in the treatment of knee osteoarthritis. 7 studies (n=449) met selection and exclusion criteria out of 287 potential studies obtained from the literature search via Ovid-Medline, Cochrane Library CENTRAL, CINAHL, RISS and KISS. The overall risk of bias of selected studies using SIGN (Scottish Intercollegiate Guidelines Network) checklist for randomized controlled trials (RCT) was regarded as low. As a result of meta analysis, Standardized Mean Difference (SMD) for pain was -0.26(95% CI -0.49, -0.03, p=0.03, $I^2=14%$), which implies that aquatic exercise groups had significant less pain than land-based exercise groups. On the other hand, there was no significant difference between aquatic exercise groups and land based exercise groups for flexion Range of Motion (ROM) (-0.12, 95% CI -0.51, 0.27, p=0.53, $I^2=0%$), extension ROM (-0.04, 95% CI -0.55, 0.48, p=0.89, $I^2=43%$), physical function (-0.12, 95% CI -0.44, 0.19, p=0.44, $I^2=0%$), Quality of Life (QOL) (-0.15, 95% CI -0.54, 0.24, p=0.46, $I^2=0%$). This study has some limitations due to few RCTs comparing aquatic exercise groups and land-based exercise groups in the treatment of knee osteoarthritis. Therefore, further RCTs should be conducted along with long-term outcomes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.5
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• pp.561-568
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• 2009

To investigate the effects of garlic and medicinal plants extracts (GP) on liver function and lipid metabolism of rat administered with ethanol chronically, Sprague-Dawly male rats were fed with a basial diet (Normal), a basial diet plus ethanol (Control, 10 mL of 20% ethanol/kg b.w/day), a control diet plus 0.5% garlic and 1.0% medicinal plants extracts (GP-I), and a control diet plus 1.0% garlic and medicinal plants extracts (GP-II) for 4 weeks. Blood glucose in GP group was significantly decreased, but not significantly different between GP-I and GP-II group. Albumin content of serum was significantly increased in GP groups, while total lipid, cholesterol and triglyceride of serum were significantly decreased in GP group. Total cholesterol and triglyceride were not significantly different between GP-I and GP-II group. LDL-cholesterol in blood was decreased to 58% in GP-I group and 73% in GP-II group compared to the control group, it's contents were the lowest amounts among the normal, control and experimented groups. Lipid levels in liver of rat administered with alcohol were decreased in GP group and significantly different in GP-II group. GOT and r-GTP activities were significantly higher in control than normal group, while GPT and ALP activities were not significant in groups administered with alcohol. Activities of GOT, GPT and r-GTP were significantly lower in GP group than control group, while ALP activity was not significant in all groups. TBARS contents were not significant in serum, but it's contents in liver were significantly decreased in GP groups than control group. DPPH radical scavenging ability in serum and liver was significantly increased in GP groups. These results indicate that garlic and medicinal plants extracts were effective in improving and protecting liver disorder induced from long-term alcohol consumption.