• Journal of Sericultural and Entomological Science
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• v.42 no.2
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• pp.99-103
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• 2000

This study was carried out to investigate incubating characteristics, LTSEM observation, nature of a disease of infected silkworms(bombyx mori), LD$\_$50/, optimum infective condition for mass production and infection percentage(%) on conservation periods. On the V8 media, the colony was 0.5∼2.0cm/8 days in diameter and white or slighty colored with a white fluffy to powdery appearance. The conidia was subglobos in shape, zig-zag appearance, 1-celled, hyaline and 3.2$\times$2.4 ㎛ in size on the average. The conidiophore was irregular grouped, hyaline, rounded or flask-shaped. The LD$\_$50/ values of the 2nd and 4th silkworms were each other 6.6142(Log) in natural temperature and humidity (25$\^{C}$, 65%). On optimum infective condition for mass production, all of preservation time(hr.) postinoculation in 1.0$\times$10$\^$8/ conidia/㎖ was over 97% and only 20 hr in 1.0$\times$10$\^$7/ condia/㎖ was over 90%.

• Macromolecular Research
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• v.16 no.8
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• pp.717-724
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• 2008

In this study, we prepared all-trans retinoic acid (ATRA)-encapsulated, surfactant-free, PLGA nanoparticles. The nanoparticles were formed by nanoprecipitation process, after which the solvent was removed by solvent evaporation or dialysis method. When a nanoparticle was prepared by the nanoprecipitation - solvent evaporation method, the nanoparticles were bigger than the nanoparticles of the nanoprecipitation - dialysis method, despite the higher although loading efficiency. Nanoparticles from the nanoprecipitation - dialysis method were smaller than 200 nm in diameter, while the loading efficiency was not significantly changed. Especially, nanoparticles prepared from DMAc, 1,4-dioxane, and DMF had a diameter of less than 100 nm. In the transmission electron microscopy (TEM) observations, all of the nanoparticles showed spherical shapes. The loading efficiency of ATRA was higher than 90% (w/w) at all formulations with exception of THF. The drug content was increased with increasing drug-feeding amount while the loading efficiency was decreased. In the drug release study, an initial burst was observed for $2{\sim}6$ days according to the variations of the formulation, after which the drug was continuously released over one month. Nanoparticles from the nanoprecipitation - dialysis method showed faster drug release than those from the nanoprecipitation - solvent evaporation method. The decreased drug release kinetics was observed at lower drug contents. In the tumor cell cytotoxicity test, ATRA-encapsulated, surfactant-free, PLGA nanoparticles exhibited similar cytotoxicity with that of ATRA itself.

• Journal of Forest and Environmental Science
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• v.28 no.2
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• pp.68-74
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• 2012

A total of 45 Pinus sylvestnis var. mongolica trees from 9 plots in northeast China were destructively sampled to develop aboveground prediction equations for inventory application. Sampling plots covered a range of stand ages (12-47-years-old) and densities (450-3,840/ha). The distribution of aboveground biomass of whole-trees and tree component (stems, branches and leaves) of individual trees were studied and 4 equations were developed as functions of diameter at breast height (DBH), total height (HT). All the equations have good estimation effect with high prediction precision over 90%. Forest biomass was estimated based on the individual biomass prediction equations. It was found forest biomass of all organs increased with the increasing of stand age and density. And the period of 45-50 years was the suitable harvest time for Pinus sylvesris plantation.

• International Journal of Aeronautical and Space Sciences
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• v.2 no.2
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• pp.82-94
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• 2001

The purpose of this paper is to analyze the static and dynamic stability-of the unmanned airship under development ; the target airship's over-all length of hull is 50m and the maximum diameter is 12.5m. For the analysis, the dynamic model of an airship was defined and both the nonlinear and linear dynamic equations of motion were derived. Two different configuration models (KA002Y and KA003Y) of the airship were used for the target model of the static stability analysis and the dynamic stability analysis. From the result of analyses, though the airship is unstable in static stability, dynamic characteristics of the airship can provide the stable dynamic stability. All of the results, airship models and dynamic flight equations will be an important basement and basic information for the next step of developing the automatic flight control system(AFCS) and the stability augmentation system(SAS) for the unmanned airship as well as for the stratospheric airship in the future.

• Korean Journal of Plant Resources
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• v.20 no.1
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• pp.7-11
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• 2007

This study was conducted by estimate of leaf characteristics and growth performance among selected 20 families progenies of Hovenia dulcis var. koreana Nakai. Mean seedling height and root-collar diameter in whole progenies showed 61.6cm, 6.98mm, respectively. Mean seedling height of KW 2-5 family was 79.3cm and it was higher than that of other families. JN 2-2 family had highest value, 9.16mm, in mean of root-collar diameter. Growth performances of KW 2-5 and JN 2-2 families showed 57% (in seedling height), 53% (in root-collar diameter) superior to those of lowest marked families. The selection level based on growth performances, which are seedling height over 75.0cm and root-collar diameter over 8.0mm, were applied on whole families, and two families selected (KW 2-5, JN 2-2). The selection effects from selected families was evaluated as 125% compared to the mean of whole families. The coefficient of variation (C.V) appeared wide range, $9.4{\sim}42.4%$, in estimated leaf characteristics. Particularly, C.V of petiole length (PL) and petiole diameter (PD) showed 42.4% and 28.7%, respectively. Their were higher value than other leaf characteristics. Analysis of variance for all leaf characteristics were significantly different among families. Also, there had positive correlation between most leaf characteristics except the correlation between leaf length (LL) and leaf morphological index (LMI, LW/LL). Particularly, the correlation between leaf length and leaf width (LW) showed the highest correlation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.504-508
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• 1983

To define the effects of synthetic auxins on rooting from the ginseng stern cutting and the root growth in diameter after the rooting of the cuttings, stern cuttings with palmate leaves obtained from seedlings and 2-year old ginseng plants were planted in rooting media treated with solutions of the synthetic auxins. All the roots induced from the cuttings were adventitious fibrous roots at first, but a few adventitious roots of the cutting were thickened in diameter to over 2 to 3mm at 120 days after cutting and the rest of them disappeared. IBA was the most effective auxin for rooting and root growth in diameter after rooting from the cuttings. The shape of the roots that thickened in diameter could be divided into two types. Both types of thickened roots were fully lignified at 120 days after cutting and those thickened roots did not dry up or die by July of the next year, however no rhyzomes or shoot primodia were induced from them.

• Journal of Periodontal and Implant Science
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• v.50 no.1
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• pp.48-55
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• 2020

Purpose: The purpose of this study was to utilize cone-beam computed tomography (CBCT) image analysis to obtain anatomical information related to the morphology of the incisive foramen to provide useful data regarding implant placement and clinical procedures such as anesthesia. Methods: The study included 167 patients who underwent CBCT scans over 20 years. Three components were measured: 1) the anteroposterior and mediolateral diameter of the incisive foramen, 2) the horizontal bone thickness anterior to the incisive foramen, and 3) the vertical bone height coronal to the incisive foramen. All measurements were expressed as mean±standard deviation and were analyzed by a single examiner. Results: The anteroposterior diameter of the incisive foramen was wider than the mediolateral diameter (P<0.001). The diameter of the incisive foramen in patients in whom the central incisors were present was smaller than that in those in whom at least one central incisor was absent, but no statistically significant difference between the groups was observed. The horizontal bone thickness in the patients with central incisors was statistically significantly larger than that in the patients without at least one central incisor (P<0.001). The same pattern was observed with regard to vertical height, but that difference was not statistically significant. Conclusions: The buccal bone thickness anterior to the incisive foramen was significantly decreased after central incisor loss. It is necessary to identify the morphology of the bone and the location of the incisive foramen via CBCT to avoid invasion of the incisive foramen and nasopalatine canal.

• Mycobiology
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• v.48 no.5
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• pp.383-391
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• 2020

Use of nanoparticles (NPs) in several commercial products has led to emergence of novel contaminants of air, soil and water bodies. The NPs may exhibit greater ecotoxicity due to nano-scale dependent properties over their bulk counterparts. The present investigation explores the effect of in vitro supplementation of TiO₂, silica and silver NPs on radial growth and ultrastructural changes in the hyphae and spores of two mushroom genera, Ganoderma lucidum and Volvariella volvaceae. A concentration dependent decrease in radial growth on NP amended potato dextrose agar medium was recorded. However, in comparison to control, there was decrease in radial diameter on supplementation with TiO₂ NPs while an increase was recorded for silica and silver NPs amendments as compared to their bulk salts at same concentrations after 48 h of incubation. Optical microscopy studies showed decrease in the number of spores while increase in spore diameter and thinning of hyphal diameter on NPs supplementation. Scanning electron microscopy analysis of fungal growth showed presence of deflated and oblong spores in two fruiting strains of Ganoderma while Volvariella exhibited decreased sporulation. Further, hyphal thinning and branching was recorded in response to NP amendments in both the test mushrooms. Enhancement of protein content was observed on NP compared to bulk supplementation for all cultures, concentrations and hours of incubation except for TiO₂ NPs. Likewise, bulk and NP supplementations (at 100 mg L^-1) resulted in enhanced laccase activity with occurrence of laccase specific protein bands on SDS-PAGE analysis.

• Korean Journal of Plant Resources
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• v.8 no.2
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• pp.143-151
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• 1995

The development of medicinal plants for cut plants and landscape plants were conducted through the literiture survey. The results were as follows: We selected 38 species of medicinal plants including 7 medicinal woody plants for cut plant and landscape plants from 450 medicinal plants. There were 8 species of Compositae, 4 species Ranunculaceae, 3 species Rosaceae and Umbelliferae, 2 species Polygonaceae and Campanulaceae respectively. The anthesis of Cornus officinalis, Magnolia denudata, Forsythia koreana of medicinal woody plants flowering before leaf spreading come to early than the anthesis of other medicinal plants. There were 4 species(11%) over 10cm of the flower diameter, 6 species(16%) over 5cm below 10cm, 19 species(50%) over 1cm below 5cm and 9 species(24%) 1cm below. In terms of flower color, 11 species(29%) were white, 9 species(24%) yellow, 6 pecies(16%) red, 5 species(13%) violet and 3 species(8%) were blue aided violet. In terms of the flowering by month, 12 species(32%) on July, 9 species(24%) on May, 6 species(16%) on June and August respectively, and 3 species(8%) on March. The most medicinal plants were propagated by division and seeding easily, but woody medicinal plants of 7 species of this study were propagated by cutting and grafting easily. The percentage of usage of parts of medicinal plants including woody medicinal plants was that roots were 20 species(53%), flowers 6 species(16%), fruits and all part of medicinal plants were 4 species(11%), and seeds and stem including leaves 2 species(5%) respectively.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1754-1759
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• 2003

Two-dimensional flow over a pair of circular cylinders in side-by-side arrangements at low Reynolds numbers has been numerically investigated in this study. Numerical simulations are performed, using the immersed boundary method, in the ranges of $40{\leq}Re{\leq}160$ and $g^{\ast}<5$, where Re and $g^{\ast}$ are, respectively, the Reynolds number and the spacing between the two cylinder surfaces divided by the cylinder diameter. Results show that total six kinds of wake patterns are observed over the ranges: antiphase-synchronized, inphase-synchronized, flip-flopping, single bluff-body, deflected, and steady wake patterns. It is found that the characteristics of the flow significantly depends both on the Reynolds number and gap spacing, with the latter much stronger than the former. Instantaneous flow fields, time traces, flow statistics and so on are presented to identify the wake patterns and then to understand the underlying mechanism. It is remarkable that, for the deflected wake pattern, the gap flow is deflected invariably to the cylinder of higher drag coefficient and the deflection way does not change at all. Moreover, the bifurcation phenomena where either of two wake patterns can occur are found at certain flow conditions.