• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.297-316
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• 2018

The golden apple snail (GAS, Pomacea canaliculata) is an invasive freshwater snail. The GAS was introduced in Korea without prior studies on the possibility of crop damage or its impact on the natural ecosystem. The freshwater apple snails can be found typically in ponds, rice paddies, irrigation canals, roadside ditches or slower portions of streams. In this study, we were carried out to investigate the assessment of physiological and ecological characteristics, environmental characteristics inhabited area in winter season and cause of massive death at one time of golden apple snails used for weed control in wet rice paddies. The GAS was introduced from Japan to Korea for commercial production as a dietary protein supplement. The golden apple snail was also used a recently for weed control in wet rice cultivation. The species of freshwater Pomacea snails is belonging to the genus Pomacea, family ampulariidae, order mesogastropoda, subclass pulmonata, class gastropoda, phylum mollusca. The GAS spread into irrigation ditches and natural waterways. It is now distributed in ponds and canals near rice fields of southern parts of the country and has overwintered. It increases its cold hardiness before winter. However, the physiological mechanism of cold hardiness in molluscs is poorly understood, especially in freshwater molluscs. Our results on physio-ecological characteristics of the Pomacea apple snail showed that the ratio of males to females was 1: 1.99~2.33. The daily growth was 87.7 mg in weight, 0.31 mm in height and 0.33 mm in width of the their shell. On the other hand, the golden apple snails were very high to resistance on drying condition and survived rate about 80% up to 3 months. The inhabitation of GAS was no statistical significant impacts on the water quality. An important property of aqueous solutions is agricultural water quality because it affects chemical and biochemical properties such as chemical reactions, equilibrium conditions, and biological toxicity. The death rate of weed control apple snails by Ostracoda (Stenocypris hislopi) was only 2.86% and 5.71% depending on the density. Therefore, GAS was not a direct death caused by Ostracoda (Stenocypris hislopi).

• Food Science and Preservation
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• v.18 no.2
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• pp.165-170
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• 2011

The physicochemical properties and cooking quality of Saechalssal bori (25% pearled ratio), which is a naked waxy barley, were investigated. The amylose, insoluble dietary fiber (IDF), soluble dietary fiber (SDF), total dietary fiber (TDF), and ${\beta}$-glucan contents of Saechalssal bori were 5.2, 10.8, 9.5, 20.3, and 3.7%, respectively. Pasting temperature, peak and final viscosity, and setback of Saechalssal bori were $66.5^{\circ}C$, 383.2, 231.3, and 55.6 RVU, respectively. The water absorption, expansibility, and soluble solid of Saechalssal bori were 232.2, 405.3, and 3.5%, respectively. As the ratio of water to grain increased, L value increased, whereas a and b values were decreased. The sensory evaluation showed that wateriness and overall acceptability increased with increasing ratio of water to grain, resulting in determining 2.1 times as the optimum ratio of water to grain. The cooked Saechalssal bori prepared using optimum condition had hardness (1.2 kg), cohesiveness (4.0), springiness (1.0), gumminess (5.1), chewiness (5.3), adhesiveness (0.2 kg), and A/H (0.8), respectively.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.33-40
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• 2008

Objectives : In order to distinguish morphological characteristics, because the inside portion of the root bark of Scutellariae Radix decomposes as time goes by, 2nd, 3rd, and 5th year Scutellariae Radix were sampled and compared according to their external, internal, and flour states through optical microscope. Methods : The slice of the tested material made by paraffin section technique was colored with Safranine Malachite Green contrast methods, and the flour of it was mounted by the liquid made by the same ratio of each of glycerin, acetic acid, and water, and then observed and photographed by olymphus-BHT. Results : 1. The inside of 2nd year Scutellariae Radix was rich and golden, the transverse section of Scutellariae Radix that was 3rd years of age was golden, but there were many Scutellariae Radix whose center portion turned redish brown, and the center portion of 5th year Scutellariae Radix had been decomposed or empty. 2. 2nd year Scutellariae Radix had the most starch grain, 5th year Scutellariae Radix had the least, and the middle portion of xylem that was 5 years of age had a cell ring that was corkish, but 2nd and 3rd year Scutellariae Radix did not have it. 3. In the flour state, 2nd, 3rd, and 5th year Scutellariae Radix did not have any difference, but the amount of starch grain was the most in 2nd year Scutellariae Radix and the least in 5th year Scutellariae Radix.

• Korean Journal of Plant Tissue Culture
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• v.22 no.4
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• pp.217-221
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• 1995

This experiment was carried out to determine the effects of genotyes (cultivars) and kinds of cytokinins and concentrations on shoot multiplication of roses (Rosa hybrida) by nodal culture. The results from this study were summarized as follows. Shoot multiplication was significantly affected by genotypes. Most shoots were produced from 'Carl Red 'rather than two other cultivars, 'Golden Emblem' and 'Tineke'. Among 3 cytokinins, BA was more significantly effective for multiplication than two other cytokinins, 2iP and kinetin. However subsequent shoot growth after multiplication was more enhanced by 2iP and kinetin rather than BA. An optimal concentration of cytokinin for shoot multiplication was 1 mg/L in this study but BA at 1-5 mg/L was considered optimal for multiplication ratio itself. Subsequent shoot growth was significantly inhibited by increases in cytokinin concentrations, regardless of kinds of cytokinin.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.1
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• pp.161-166
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• 2004

In this research, TiN films has been grown to the stainless steel substrate by ion beam assisted deposition. TiN film was grown to the nitrogen atmosphere of around $10^{-15}$ Torr with Arion bombardment. The chemical composition, color and adhesion of TiN films were examined as a variation of En(ion energy per atom). The N/Ti ratio increased linearly as the increase of En and saturated around 1.2 at high En. As a results, the bright golden color was obtained when En reached a certain value of Ecn. As a results, the N/Ti ratio is about 0.9.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.119-124
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• 1979

In order to examine $SO_2$ injury to apple shoots, cutting shoots of five cultivars were exposed to 3 ppm $SO_2$ in vase life conditions. 1. The most sensitive cultivar to $SO_2$ was 'Rall's Genet', and 'Starking' was most tolerant among cultivars tested. 2. Ethylene production of shoots showed peak after 8 hours exposure, when visible injury was not appeared, and was decreased with increase in exposure time. 'Rall's Genet' showed slower decrease in ethylene production than other cultivars. 3. Chlorophyll a, b and a/b ratio were decreased in all cultivars after 40-hr exposures to 3 ppm $SO_2$ and greatly decreased in 'Rall's Genet' compared to other cultivars.

• Earthquakes and Structures
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• v.18 no.5
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• pp.625-635
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• 2020

Suspension bridges have the extended in plan configuration which makes them prone to dynamic events like earthquake. The longer span lead to more flexibility and slender of them. So, control systems seem to be essential in order to protect them against ground motion excitation. Tuned mass damper or in brief TMD is a passive control system that its efficiency is practically proven. Moreover, its parameters i.e. mass ratio, tuning frequency and damping ratio can be optimized in a manner providing the best performance. Meta-heuristic optimization algorithm is a powerful tool to gain this aim. In this study, TMD parameters are optimized in different-length suspension bridges in three distinct cases including 3, 4 and 5 TMDs by observer-teacher-learner based algorithm under a complete set of ground motions formed from both near-field and far-field instances. The Vincent Thomas, Tacoma Narrows and Golden Gate suspension bridges are selected for case studies as short, mean and long span ones, respectively. The results indicate that All cases of used TMDs result in response reduction and case 4TMD can be more suitable for bridges in near and far-field conditions.

• Archives of Pharmacal Research
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• v.26 no.8
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• pp.659-665
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• 2003

We have studied the effect of rhEGF on the buccal mucosal ulcer healing. rhEGF was rapidly degraded upon incubation with the hamster buccal mucosal homogenates; The degradation of rhEGF was significantly inhibited by sodium lauryl sulfate (SLS). Eudispert hv hydrogel and Polycarbophil 974P hydrogel were prepared for rhEGF delivery and their mucoadhesiveness was measured by the $Instron^R$ method. The mucoadhesive force of Eudispert hv was significantly greater than that of Polycarbophil 974P. Moreover, rhEGF in Eudispert hv hydrogel remained stable for about 2 months. To evaluate the ulcer healing effect of rhEGF, the buccal mucosal ulcer was induced in golden hamsters using acetic acid. At 24 h after administration of rhEGF/Eudispert hv hydrogel, the ulcerous area was decreased compared with rhEGF solution and, as a result, the curative ratio was $36.8\pm5.68$%. By the addition of SLS (0.5%) to Eudispert hv hydrogel, the curative ratio increased 1.5 times. The mechanism of the action was probably due to a combination of protection of the drug against proteases present in mucosa and prolongation of the release of rhEGF from the formulation at the site of action.

• Journal of Veterinary Clinics
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• v.38 no.5
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• pp.221-224
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• 2021

A 8-year-old male Golden Retriever dog with bilateral cryptorchidism presented for evaluation of symmetric alopecia and gynecomastia. Abdominal radiography and computed tomography revealed bilateral enlargement of the testicles in the abdominal cavity. The concentrations of estradiol and testosterone in the blood were evaluated, and the results revealed a low testosterone/estradiol ratio despite a normal concentration of estradiol. For correction, cryptorchid testicles were surgically removed. Grossly, the bilateral retroperitoneal cryptorchid testicles were enlarged, firm, and spherical. On histopathologic examination, the right abdominal cryptorchid testicle was diagnosed as a Sertoli cell tumor (SCT)-Seminoma (SEM) combination. The contralateral testicle in the abdomen was diagnosed as a Sertoli cell tumor. The clinical signs of feminization were improved after surgery. To our knowledge, this is the first report of a case of simultaneous SCT on one side and SCT-SEM combination on the other side with sex hormone profiles in a dog.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.10
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• pp.1335-1342
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• 2000

Three-dimensional flow analysis and numerical optimization methods are presented for the design of an axial-flow fan. Steady, incompressible, three-dimensional Reynolds-averaged Navier-Stokes equations are used as governing equations, and standard k- ${\varepsilon}$ turbulence model is chosen as a turbulence model. Governing equations are discretized using finite volume method. Steepest descent method, conjugate gradient method and BFGS method are compared to determine the searching directions. Golden section method and quadratic fit-sectioning method are tested for one dimensional search. Objective function is defined as a ratio of generation rate of the turbulent kinetic energy to pressure head. Two variables concerning sweep angle distribution are selected as the design variables. Performance of the final fan designed by the optimization was tested experimentally.