• Applied Microscopy
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• v.29 no.3
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• pp.303-313
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• 1999

In this paper, five kinds of neurosecretory cells-light green (LG) cell, dark green (DG) cell, caudo-dorsal (CD) cell, blue green (BG) cell, and yellow (Y) cell- and neuropils in the cerebral ganglion of the African giant snail, Achatina fulica, were observed with an electron microscope. The following results were obtained. The LG cells are circular or ovoid in shape, and about $60{\mu}m$ in size. The nucleus and cytoplasm of the LG cell look light due to their electron-low density. Large granular chromatins are evenly developed in the karyolymph, where round nucleoli are also found. In the cytoplasm, electron -high dense round granules of $0.4{\mu}m$ in average size are crowded. The DG cells are ovoid in shape, and $50\sim20{\mu}m$ in size. These relatively electron-high dense cells were rarely found. In their cytoplasm, cell organelles such as rough endoplasmic reticulum and mitochondria are found together with electron -high dense round granules of $0.2{\mu}m$ in average size. The CD cells are ellipsoidal cells densely distributed in caudo-dorsal parts of the cerebral ganglion. They have large nuclei compared with the cytoplasm. The developed granular heterochromatins are observed in the karyolymph, and lots of small round granules of $0.12{\mu}m$ in average size in the cytoplasm. The 3G cells, rarely found around endoneurium of the cerebral ganglion, take the shapes of long ellipses. They look dark due to their electron -high density. In the cytoplasm, small round granules of $0.1{\mu}m$ in average size are found. The Y cells are the smallest among the neurosecretory cells($9\times6.6{\mu}m$ in size). They are found mostly between the medio-dorsal parts and the caudo-dorsal parts of the cerebral ganglion. In the cytoplasm, tiny round granules of $0.08{\mu}m$ in average size form a group. The neuropils are found in the middle of the cerebral ganglion. In the axon ending, round granules with electron -high density ($0.07\sim0.03{\mu}m$ in diameter) and lucent vesicles ($0.03{\mu}m$ in diameter) are found in large quantities. They are excreted in the state of exocytosome formed by the invagination of the limiting membrane of the axon ending.

• Journal of Life Science
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• v.20 no.1
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• pp.147-152
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• 2010

Exercise-induced anaphylaxis (EIA) is a physical allergy, sometimes severe, triggered by exertion following specific food intake. It was defined for the first time in 1980. EIA is associated with different kinds of exercise. The clinical manifestations progress from itching, erythema and urticaria to some combination of cutaneous angioedema and vascular collapse. Mast cell participation in the pathogenesis of this syndrome has been proved by the findings of an elevated serum histamine level during exhaustive exercise. As predisposing factors of EIA, a specific or even nonspecific sensitivity to food has been reported. Food-dependent exercise-induced anaphylaxis (FDEIA) is a distinct form of food allergy induced by physical exercise. It is typified by the onset of anaphylaxis during exercise which was preceded by the ingestion of the causal food allergens. The diagnosis of FDEIA is heavily dependent on clinical history. Allergy tests may need to be performed using a broad panel of food and food additives. As with food allergies, FDEIA diagnosis is based on interview, biological test and skin test. Prophylaxis aims to prevent a recurrence; the patient should be given an emergency kit to deal with any recurrent episodes. After the food allergen has been identified, it should be avoided for at least 4 to 5 hours before any exercise. Two cases of EIA are presented (EIA to circumstances; FDEIA) in this paper, The diagnosis, pathophysiology and therapy of FDEIA are also reviewed.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.138-143
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• 2003

Total methanolic extract of Chrysanthemum coronarium L. var. spatiosum (Compositae) was revealed to have anti-hepatotoxic activity against galactosamine-induced toxicity on primary cultured rat hepatocytes. After successive partitioning with chloroform, n-butanol, and water, the chloroform fraction showed a significant inhibition activity of 51% at 50 ppm, compared with that of silybin, 45.9% at $100\;{\mu}M$. The chloroform fraction was subjected to silica gel column chromatography and yielded active CH-II, CH-V and CH-VI subfractions, and the anti-hepatotoxic activity of these subfractions were 47.6, 56.3, and 23.2%, respectively, at 50 ppm. Total glutathione contents of CH-II, CH-V, and CH-VI increased by 49.8, 43.9, and 47.5% of the control, respectively at 50 ppm, whereas that of silymarin was, 59.7% at $100\;{\mu}M$ after challenged with galactosamine. The ratio of (reduced glutathione) / (total glutathione) in CH-II, CH-V and CH-VI subfraction showed similar values of $0.86{\sim}0.87$ at 50 ppm, whereas that of silymarin was, 0.85 at $100\;{\mu}M$. The incorporation of $[^3H]-uridine$ uptake into RNA was not affected by these active subfractions.

• Applied Microscopy
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• v.32 no.2
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• pp.131-147
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• 2002

Optic lobes of Todarodes pacificus and Octopus minor are largely divided into cortex and medulla, the cortex being composed of three layers (an outer granule cell layer, a plexiform layer, and an inner granule cell layer). The cortex of Todarodes pacificus is about $420{\sim}450{\mu}m$ thick, being $170{\sim}200{\mu}m$ thicker than that of Octopus minor of which thickness is about $250{\sim}290{\mu}m$. In the outer granule cell layer of Todarodes pacificus, three types of nerve cells (type-A, type-B and type-C) and neuroglial cells that surround or contact with the neurons are observed, while in the outer granule cell layer of Octopus minor, two types of nerve cells (type-A and type-B) and a single type of neuroglial cells are observed. In a plexiform layer, a presynaptic bag and nerve endings are connected to each other, consequently forming various types of synaptosomes. The synaptosomes of Todarodes pacificus contain electron dense vesicles, electron dense-core vesicles and electron lucent vesicles, either individually or in a mixture. On the other hand, three types of synaptosomes a mixture of electron dense-core vesicles and electron lucent vesicles, electron lucent vesicles only, and electron dense-core vesicles only are observed in Octopus minor. The structures of the inner granule cell layer are almost similar in the two species. It is composed of two types of nerve cells (type-A, type-B) and a single type of neuroglial cells. In the medulla of Todarodes pacificus, the cells of $7{\times}5{\mu}m$ are arranged to a line and form the palisade cell layer, but these are not observed in Octopus minor.

• Korean Journal of Environment and Ecology
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• v.25 no.3
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• pp.284-294
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• 2011

This study was conducted to investigate the flora of habitats distributed with Allium victorialis var. platyphyllum populations in the South Korea. The vascular plants were surveyed 4 times from March 2009 to June 2010. The flora of studied area was listed as 214 taxa; 64 families, 142 genus, 181 species, 2 subspecies, 30 varieties, 1 forma. According to the specific plant species by classes, class I has 17 taxa; 15 families, 16 genus, 15 species, 2 varieties. Class II has 16 taxa; 13 families, 16 genus, 15 species, 2 varieties. Class III has 20 taxa; 16 families, 19 genus, 18 species, 2 varieties. Class III has 20 taxa; 16 families, 19 genus, 18 species, 2 varieties. Class IV has 23 taxa; 20 families, 23 genus, 19 species, 4 varieties. Class V has 2 taxa; 2 families, 2 genus, 2 species. Rare plant was 12 taxa; 9 families, 11 genus, 10 species, 2 varieties. Endemic plant was 21 taxa; 17 families, 19 genus, 18 species, 3 varieties. Endangered plant was not present in study area. It was considered that the ecosystem was probably stabilized for nothing of naturalized species and ecosystem disturbance species there. The characteristics of growth environments in the habitats with Allium victorialis var. platyphyllum were considered to be related to valley species and subalpine species such as Actinidia polygama, Cornus controversa, Rhododendron brachycarpum and Sorbus commixta.

• Korean Journal of Food Science and Technology
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• v.37 no.6
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• pp.882-888
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• 2005

Procedure for analysis of methylmercury in fish was developed, involving addition of HCl, extraction with toluene, and clean-up using L-cystein solution. Obtained extract is analyzed by gas chromatography with electron capture detector using Ulbon HR-Thermon-Hg column. Detection limit and recovery of the method were 0.005mg/kg (expressed as Hg), 98-107 (103%), respectively. Total mercury and methylmercury concentrations in 175 commercial fish samples ranged from [mean-max (mean), unit: mg/kg]: 0.014-1.200 (0.270) and 0.006-0.901 (0.168) in tuna-fish, 0.020-0.934 (0.323) and 0.012-0.553 (0.149) in martin-fish, 0.082-0.782 (0.391) and 0.040-0.436(0.201) in shark, 0,023-0.031 (0.026) and 0,013-0.018 (0.015) in salmon, 0.098-0.193 (0.133) and 0.031-0.015(0.090) in tilefish, and 0,031-0.214 (0.089) and 0.016-0.093 (0.042) in canned tuna respectively. No sample of analyzed fish exceeded 1.0mg/kg wet wt., limit for methylmercury established by Codex. In all species examined, estimated weekly intake was lower than Provisional Tolerable Weekly Intake recommended by the JECFA (the Joint FAO/WHO Expert Committee on Food Additives).

• Journal of the Korean Applied Science and Technology
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• v.37 no.3
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• pp.463-472
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• 2020

The purpose of this study is to identify the BMI, diet perception and diet behavior of female university students. A descriptive survey design was used 165 students from October 29 to November 9, 2018. Data were analyzed using mean, t-test, ANOVA, cross analysis with SPSS 21.0. Total diet perception was 3.44 points, highest sub category was 'practice' with 4.00 points, followed by 'information and education' with 3.58 points, 'necessity' with 3.32 points and lowest category was 'self-recognition' with 2.84. 65 students(43.0%) were 'less than three times' in 'Number of diets' and diet methods was 65(43.0%) for 'food control' and 62(41.1%) for 'exercise'. During in a week, 98 students(84.9%) exercised within three hours, followed by 33(21.9%) who did not exercised at all. 22 students(14.6%) said they experienced damage from dieting, while the types included gastrointestinal disease, menstrual irregularity and hair loss. The total score of diet perception according to BMI was lower in the underweight group than in the normal and overweight groups(p<.001). In diet 'practice' category, low weight group scored lower than normal weight and overweight groups(p<.05). In 'information and education' category, overweight group scored the highest, followed by normal and underweight groups(p<.001). In diet 'necessity' and 'self-recognition' categories, low weight group scored lower than normal weight and overweight groups(p<.001). Diet behavior by diet perception was different in number and method of diet(p<.001). Based on the results, it is thought that attention and education are needed to form a proper diet perception and maintain healthy living for female university students.

• Journal of the Korean GEO-environmental Society
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• v.18 no.7
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• pp.37-47
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• 2017

In this study, a series of full-scale field tests on prebored and precast steel pipe piles and the corresponding numerical analysis have been conducted in order to study the characteristics of pile load-settlement relations and shear stress transfer at the pile-soil interface. Dynamic pile load tests (EOID and restrike) have been performed on the piles and the estimated design pile loads from EOID and restrike tests were analysed. Class-A type numerical analyses conducted prior to the pile loading tests were 56~105%, 65~121% and 38~142% respectively of those obtained from static load tests. In addition, design loads estimated from the restrike tests indicate increases of 12~60% compared to those estimated in the EOID tests. The EOID tests show large end bearing capacity while the restrike tests demonstrate increased skin friction. When impact energy is insufficient during the restrike tests, the end bearing capacity may be underestimated. It has been found that total pile capacity would be reasonably estimated if skin friction from the restrike tests and end bearing capacity from the EOID are combined. The load-settlement relation measured from the static pile load tests and estimated from the numerical modelling is in general agreement until yielding occurs, after which results from the numerical analyses substantially deviated away from those obtained from the static load tests. The measured pile behaviour from the static load tests shows somewhat similar behaviour of perfectly-elastic plastic materials after yielding with a small increase in the pile load, while the numerical analyses demonstrates a gradual increase in the pile load associated with strain hardening approaching ultimate pile load. It has been discussed that the load-settlement relation mainly depends upon the stiffness of the ground, whilst the shear transfer mechanism depends on shear strength parameters.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.853-869
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• 2000

Background : Following several decades of decline, the incidence of tuberculosis has recent1y begun to increase in many countries of this the control of this disease has been impeded by the emergence of multi-drug resistant tuberculosis (MDR-TB). The development of rapid diagnostic methods and effective new drugs are needed to control MDR-TB. One of the new drugs for MDR-TB is rifabutin (RBU) which has been known to be effective in some patients with MDR-TB. A few reports showed that some types of mutations of the rpoB gene, which were known to be present in 96-98% of rifampicin-resistant M. tuberculosis, were associated with the rifampicin-resistant but RBU-susceptible phenotype. This study was performed to investigate the correlation between RBU susceptibility and the patterns of rpoB gene mutations in Korean MDR-TB. Methods : Sixty-five clinical isolates of multi-drug resistant Mycobacterium tuberculosis, gathered from patients who visited the Asan Medical Center from July 1997 to June 1999, were investigated. Clinical responses to rifabutin-containing regimen were evaluated. An RBU susceptibility test and sequencing analysis of rpoB gene were performed, and the results were analyzed to confirm which mutations correlated with RBU-susceptible MDR-TB. Results : Fifty-three of 56 (95%) clinical isolates of MDR-TB had 60 mutations of the rpoB gene. The most frequent mutations were found at codon 531 (43%), and two mutations were combined in seven clinical isolates. Five of 53 (10%) clinical isolates showed the RBU-susceptible phenotype, and in them the characteristic patterns of point mutations were found at codon 509, 516, and 526. Conclusion : The frequency and pattern of mutations of the rpoB gene of Korean MDR-TB isolates were similar to those in western countries, where the prevalence of tuberculosis is low, but some show RBU-susceptible phenotypes. RBU-susceptible MDR-TB isolates showed the characteristic pattern of mutations of the rpoB gene which could be used to rapidly diagnose RBU susceptibility.

• Journal of Korean Home Economics Education Association
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• v.19 no.4
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• pp.91-117
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• 2007

This study was to compare the contents and practical problems addressed, the process of teaching-learning method, and evaluation method of Korean Home Economics curriculum and of the Oregon and Ohio's Practical Problem Focused Family & Consumer Sciences Curricula. The results are as follows. First, contents of Korean curriculum are organized by major sub-concepts of Home Economics academic discipline whereas curricular of both Oregon and Ohio states are organized by practical problems. Oregon uses the practical problems which integrate multi-subjects and Ohio uses ones which are good for the contents of the module by integrating concerns or interests which are lower or detailed level (related interests). Since it differentiates interest and module and used them based on the basic concept of Family and Consumer Science, Ohio's approach could be easier for Korean teachers and students to adopt. Second, the teaching-learning process in Korean home economics classroom is mostly teacher-centered which hinders students to develop higher order thinking skills. It is recommended to use student-centered learning activities. State of Oregon and Ohio's teaching-learning process brings up the ability of problem-solving by letting students clearly analyze practical problems proposed, solve problems by themselves through group discussions and various activities, and apply what they learn to other problems. Third, Korean evaluation system is heavily rely on summative evaluation such as written tests. It is highly recommended to facilitate various performance assessment tools. Since state of Oregon and Ohio both use practical problems, they evaluate students mainly based on their activity rather than written tests. The tools for evaluation include project documents, reports of learning activity, self-evaluation, evaluation of discussion activity, peer evaluation in a group for each students for their performance, assessment about module, and written tests as well.