• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.4
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• pp.196-205
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• 2011

To investigate the contribution of macroalgae to biogeochemical nutrients and carbon cycles, we measured the uptake rates of nutrients and $CO_2$ and characteristics of fluorescence of Saccharina japonica (Laminaria japonica Areschoug) using an incubation method in an acrylic chamber. From January to May 2011, S.japonica was sampled at Ilkwang, one of well-known macroalgae culture sites around Korea and ranged 46~288 cm long and 4.8~22.0 cm wide of whole thallus. The production rate of dissolved oxygen by S. japonica (n=25) was about $6.9{\pm}5.8{\mu}mol\;g^{-1}$ fresh weight(FW) $h^{-1}$. The uptake rate of total dissolved inorganic carbon ($TCO_2$), calculated by total alkalinity and pH, was $8.9{\pm}7.9{\mu}mol\;g^{-1}\;FW\;h^{-1}$. Mean nutrients uptake were $175.6{\pm}161.1\;nmol\;N\;g^{-1}\;FW\;h^{-1}$ and $12.7{\pm}10.1\;nmol\;P\;g^{-1}\;FW\;h^{-1}$. There were logarithmic relationships between thallus length and uptake rates of nutrients and $CO_2$, which suggested that younger specimens (<100-150 cm) were much more efficient at nutrients and $CO_2$ uptake than old specimens > 150 cm. There was a positive linear correlation ($r^2$=9.4) existed between the dissolved oxygen production rate and the $TCO_2$ uptake rate, suggesting that these two factors may serve as good indicators of S. japonica photosynthesis. There was also positive linear relationship between maximal quantum yield ($F_v/F_m$) and production/uptake rates of dissolved oxygen, $TCO_2$ and phosphate, suggested that $F_v/F_m$ could be used as a good indicator of photosynthetic ability and $TCO_2$ consumption of macroalgae. Maximum relative electron transport rate ($rETR_{max}$) of S. japonica increased as thallus grew and was high in distal part of thallus which may be resulted from the increase of photosynthetic cell density per area. The annual $TCO_2$ uptake by S. japonica in Gijang area was estimated about $1.0\sim1.7{\times}10^3C$ ton, which was about 0.02-0.03% of carbon dioxide emission in Busan City. Thus, more research should be focused on macroalgae-based biogeochemical cycles to evaluate the roles and contributions of macroalgae to the global carbon cycle.

• Parasites, Hosts and Diseases
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• v.24 no.2
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• pp.109-114
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• 1986

In order to observe the growth and development of Fibricola seoulensis metacercariae, the tadpoles of Rana nigromaculata were experimentally infected with the cercariae. The meta cercariae of various developmental stages were recovered from the tadpoles after 2 to 65 days of infection. They were prepared for morphological observation, and were given orally to mice to observe their infectivity. The following results were obtained. 1. All of the tadpoles exposed to the cercariae were observed to harbour the larvae in their abdominal cavity. 2. The young metacercariae of 2 days after infection were $121.1{\mu}m$ long and $63.3{\mu}m$ wide. They grew linearly for the first 14 days to be $262.0{\mu}m$ long and $166.4{\mu}m$ wide. Thereafter, no more growth recognized until 65 days. 3. The larvae of 2 days old were similar with cercarial body and had 2 suckers, a pharynx, 2 ceca and a primordium of germ cells but no tribocytic organ. On the 8th day, they had tribocytic organ, and their morphology resembled that of mature metacercariae. 4. The metacercariae younger than 10 days could not infect the mice. Only the metacercariae older than 14 days had infectivity. The recovery rates increased by the age of metacercariae from 19.0% in 14 days old to 70.0% in 40 days old. Above findings indicate that the tadpole is indispensable for metacercarial development and it needs at least 2 weeks for maturation. The tadpole is a pivotal host in the life cycle of F. seoulensis for connection between the snail and the frog.

• Journal of Mushroom
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• v.2 no.1
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• pp.15-20
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• 2004

Pleurotus ostreatus, the oyster mushroom, is one of the most widely cultivated and important edible mushrooms in the world. In order to study the developmental process of P. ostreatus and its regulatory mechanism, a new culturing method needs to be established for inducing the fruiting body and sporulation in the laboratory. In this study, we have examined whether the fruiting body of P. ostreatus can be formed on the plastic petri dish which are commonly used for cell culture in the laboratory. The strain was cultured on $60{\times}15mm$ plastic petri dish with potato dextrose agar media at $28^{\circ}C$ for mycelial growth and then at $18^{\circ}C$ for the formation of primordia and fruiting bodies within plant growth chamber. The development of primordia into fruiting bodies was achieved on cultured dishes under air ventilation. At the primordia stage, the normal formation of fruiting body was blocked by sealing the plastic dish with parafilm. The periods requiring for the formation of primordia and fruiting bodies were examined on the dish culture. About 96% and 76% of cultured samples formed primordia and fruiting bodies under the optimal conditions during ten weeks of culture, respectively. These culturing periods, however, were changed by the mechanical injury treatment to mycelia. As other factors affecting the fruiting body formation, the effects of light and cold shock have been tested. No fruiting formation was observed on the cultured dishes under the dark. The cold shock treatment by storing cultured dishes for one day at $4^{\circ}C$ did not have any significant effects in the fruiting body formation. Spores of fruiting bodies acquired from the petri dishes could be germinated on culture media at $28^{\circ}C$. These results suggest that the fruiting bodies of P. ostreatus can be formed on the experimental petri dish and this dish-culturing method is useful for understanding of the developmental process of P. ostreatus in the laboratory. Furthermore, the dish-culturing method is able to shorten the life cycle of P. ostreatus without requiring large area and expensive device.

• Microbiology and Biotechnology Letters
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• v.43 no.1
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• pp.31-37
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• 2015

This study was conducted to investigate the bactericidal activity of electrolyzed water (EW) against coliform bacteria on Undaria pinnatifida (UP). The UP was washed with 15% EW, tap water (TW), and distilled water in the following order: 15% EW for 5 and 10 min (1st to 3rd washing process), TW for 1 min, and distilled water for 10 min (3rd to 5th washing process). The washing processes using 15% EW and distilled water occurred a total of 6 times. The number of viable cells, coliform bacteria, and molds in the untreated sample were in the range of 10¹ to 10³ CFU/g. In the case of the UP with 15% EW for 5 min sample, the viable cell counts were reduced by 1-2 log cycles as compared with the untreated sample. The coliform bacteria were not detected except after the 1st EW washing process. Mold counts were not detected in all treatments. In the UP with 15% EW for 10 min sample, the viable cells, coliform bacteria, and mold counts were not detected. In color, there were no significant differences among samples. In sensory evaluation, the UP treated with 15% EW for 10 min (first washing process) got higher scores for color, aroma, and taste than others. These results suggest that the treatment of 15% EW for 10 min is the most effective way to reduce coliform bacteria of the UP.

• Journal of Life Science
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• v.19 no.1
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• pp.101-110
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• 2009

The regulation of gene expression plays an important role in cell cycle controls. In this study, a novel $mas2^+$ (mitosis associated protein) gene, a homolog of human SMARCAD1 was isolated and characterized from a fission yeast Schizosaccharomyces pombe (S. pombe) using gene-specific polymerase chain reaction. The isolated gene contained a complete open reading frame capable of encoding 922 amino acid residues with a typical promoter, as judged by nucleotide sequence analysis. It was also found that an SNF2 domain is located, which is involved in the chromosome remodeling. The quantitative analysis of the $mas2^+$ transcript against $adh1^+$ showed that the expression level of $mas2^+$ is high before septum formation in S. pombe. When $mas2^+$ null mutant cells were grown at 27 and $35^{\circ}C$, the cytokinesis of $mas2^+$ null mutant was greatly delayed and a large number of multi-septate and mis-segregated cells were produced. In addition, the number of multi-septate cells significantly increased. When cells were cultured in YES rich medium to increase proliferation, the abnormal phenotypes $mas2^+$ null mutant dramatically increased. These phenotypes could be rescued by an over-expression of the mast gene. The Mas2 protein localized in the nuclei of S. pombe, as evidenced by Mas2-EGFP signals. These results suggest that the $mas2^+$ is homologous to human SMARCAD1 gene and involved in septum formation and chromosome remodeling control.

• Applied Microscopy
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• v.38 no.2
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• pp.141-148
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• 2008

Nitric oxide (NO) is an important regulator of renal blood flow, glomerular hemodynamics, and tubule transport processes in the kidney. There is also evidence that NO is involved in cell cycle regulation and mitotic division. During development the nNOS expression pattern differs from that observed in adult animals. However, little is known about temporal and spatial patterns of nNOS expression in the developing kidney. The purpose of this study was to establish the time of expression and the distribution of nNOS in the developing rat kidney. Kidneys from 14-, 16-, 17-, 18-, and 20-day-old fetuses, 1-, 4-, 7-, 14-, and 21-day-old pups, and adult animals were preserved and processed for immunohistochemistry. In the adult kidney, nNOS was detected in the parietal epithelium of Bowman s capsule, macula densa, descending thin limb and inner medullary collecting duct. nNOS immunoreactivity appeared first in the distal tubule anlage at 15 days of gestation, and in all epithelial cells of developing thick ascending limbs (TAL) as well as macula densa of 17- and 18-day-old fetuses. From 20 days of gestation to 14 days after birth, nNOS was expressed in the newly formed cortical TAL, which are located in the medullary ray, whereas in mature TAL of juxtamedullary nephrons, nNOS immunolabeling gradually decreased in intensity and became restricted to the macula densa. In inner medullary collecting ducts, nNOS immunoreactivity appeared first at 7 days after birth in the papillary tip and gradually ascended to the border between outer and inner medulla. In the descending thin limb and parietal epithelium of Bowman's capsule, weak nNOS immunoreactivity was observed at 14 days after birth and labeling gradually increased to adult levels at 21 days after birth. These results suggest that differential expression of nNOS in the developing kidney is an important physiological regulator of renal function during kidney maturation.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.59-67
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• 2014

Purpose : This study aims to evaluate 3D dosimetric impact for MIP image and each phase image in stereotactic body radiotherapy (SBRT) for lung cancer using volumetric modulated arc therapy (VMAT). Materials and Methods : For each of 5 patients with non-small-cell pulmonary tumors, a respiration-correlated four-dimensional computed tomography (4DCT) study was performed. We obtain ten 3D CT images corresponding to phases of a breathing cycle. Treatment plans were generated using MIP CT image and each phases 3D CT. We performed the dose verification of the TPS with use of the Ion chamber and COMPASS. The dose distribution that were 3D reconstructed using MIP CT image compared with dose distribution on the corresponding phase of the 4D CT data. Results : Gamma evaluation was performed to evaluate the accuracy of dose delivery for MIP CT data and 4D CT data of 5 patients. The average percentage of points passing the gamma criteria of 2 mm/2% about 99%. The average Homogeneity Index difference between MIP and each 3D data of patient dose was 0.03~0.04. The average difference between PTV maximum dose was 3.30 cGy, The average different Spinal Coad dose was 3.30 cGy, The average of difference with $V_{20}$, $V_{10}$, $V_5$ of Lung was -0.04%~2.32%. The average Homogeneity Index difference between MIP and each phase 3d data of all patient was -0.03~0.03. The average PTV maximum dose difference was minimum for 10% phase and maximum for 70% phase. The average Spain cord maximum dose difference was minimum for 0% phase and maximum for 50% phase. The average difference of $V_{20}$, $V_{10}$, $V_5$ of Lung show bo certain trend. Conclusion : There is no tendency of dose difference between MIP with 3D CT data of each phase. But there are appreciable difference for specific phase. It is need to study about patient group which has similar tumor location and breathing motion. Then we compare with dose distribution for each phase 3D image data or MIP image data. we will determine appropriate image data for treatment plan.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.715-732
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• 2009

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1551-1558
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• 2009

The management of skeletal health in the twenties is the number one priority for preventing fracture or osteoporosis occurrence in later life cycle. Therefore, the factors influencing bone mineral density were examined by anthropometric measurements, food intakes, bone mineral density and biochemical nutritional indexes in blood among college students. Among the students who received health examinations from May to December, 2007, 532 male and 507 female students who agreed to participate in the study were selected. Nutritional intakes were estimated with 3-day 24-hour recall method. Bone mineral density was measured by ultrasonic attenuation passing through right calcaneus bone and expressed as broadband ultrasound attenuation and t-score was calculated by WHO criteria. Red blood cell count, hemoglobin, hematocrit values were measured by whole blood analysis, and alkaline phosphatase, serum calcium and serum iron were used as indexes for biochemical nutritional status. Data analysis was conducted using SPSS 14.0 program, and protecting and risk factors on bone health status were analyzed by logistic regression analysis between normal bone health group (t-score$\underline{\geq}$ -1.0) and osteopenia group (t-score<-1.0). The results showed that more people belong to the normal bone health group probably because this study was conducted among those with their peak bone density. Biochemical nutritional status and nutrition intakes of both groups for normal and osteopenia did not show statistically significant difference except MCHC, animal protein and animal iron intakes in female. According to the results of logistic regression analyses, dietary intakes of animal protein, animal iron and zinc showed protecting effects against osteopenia. Therefore, dietary nutritional intakes of micronutrients, especially iron and zinc are important for bone health of young people.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1157-1163
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• 2011

This study was conducted to investigate the cause of microbiological contaminants in aseptic chocolate milk and evaluate the effect of a physicochemical treatment on the growth inhibition of isolated bacterial strains. The bacterium isolated from aseptic chocolate milk was identified as Bacillus lentus and was named B. lentus M1. In the heat and pH treatment, the growth of B. lentus was inhibited at 110$^{\circ}C$ for >15 min and at pH's <5 and >10. An electrolyzed water treatment against B. lentus M1, revealed 5 mm growth past the inhibition zone. The effect of ozone gas on B. lentus M1 growth was evaluated using viable cell counts. When the initial number of B. lentus M1 was $10^2$ and $10^3$ CFU, the bacteria were completely suppressed by ozone gas treatment for 10 and 30 min, respectively. In a microwave treatment, B. lentus M1 was sterilized following microwave treatment for 1 min. As the result of ${\gamma}$-irradiation against B. lentus M1, numbers decreased as the ${\gamma}$-irradiation dosage increased. These results show the growth inhibition effects against contaminants in aseptic chocolate milk using physicochemical treatments.