• Journal of the Korean Wood Science and Technology
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• v.29 no.3
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• pp.1-13
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• 2001

Compression, lateral, and opposite woods in the stem and branch of rimu (Dacrydium cupressinum Lamb.), a softwood species indigenous to New Zealand, were described and compared in the anatomical aspects. Qualitatively, growth rings were wide in the compression wood, intermediate in the lateral wood, and narrow in the opposite wood. Tracheid transition from early wood to late wood was very gradual in the compression wood but was more abrupt in both the lateral and opposite woods. When viewed transversely, compression wood tracheids showed a roundish outline except at the growth ring boundary but lateral and opposite wood tracheids were angular to rectangular in outline. Intercellular spaces were occasionally detected in the compression wood except in the late wood at the growth ring boundary but were absent from both the lateral and opposite woods. Slit-like extensions of the bordered pit openings caused by the location of pit apertures within short and narrow helical grooves were observed in the compression wood tracheids but not in the opposite or lateral wood tracheids. In the compression wood tracheids, fine striations in the form of fine checks or grooves were observed on the lumen surfaces and the innermost $S_3$ layer of secondary wall was absent. In the tracheids of lateral and opposite woods, the $S_3$ layer was sometimes absent but occasionally highly developed. Cross-field pits in the compression wood appeared to be piceoid due to slit-like pit apertures but those in the lateral and opposite wood tracheids showed cupressoid to taxodioid. Quantitatively, compression wood tracheids were somewhat shorter than those of opposite or lateral wood in stem but not different from the opposite or lateral wood tracheids in branch. The walls were thicker in the compression wood than in the lateral or opposite wood. Uniseriate rays in the compression wood were fewer than in the lateral or opposite wood.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.152-158
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• 2007

Micromorphological and chemical characteristics of living Castanea spp. and Tamarix spp. attacked by a brown-rot fungus were examined. Micromorphological features of brown-rotted hardwood species were similar to those observed in softwoods such as losses in birefringence under polarized microscopy, preferential degradation of $S_2$ layer and cracks in the $S_3$ layer. Thinning of the secondary cell wall in fibers was also observed, although it did not seem to be the main symptom. FT-IR analysis showed that bands assigned to cellulose and hemicelluloses decreased or disappeared, whereas the bands assigned to lignin increased. X-ray diffraction analysis exhibited the decrease of relative crystallinity, indicating that degradation of hardwood by a brown-rot fungus was in the advanced stages.

• Journal of Chest Surgery
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• v.13 no.1
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• pp.77-81
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• 1980

We present one case of 26-year-old male having saddle block combined with mitral valvular disease [NYHA Class IV] with auricular fibrillation. The most common cause of emboli is atrial fibrillation. The clinical manifestations of saddle emboli are relatively slow due to development of collateral circulation and large size of lumen of the aorta. The 5month duration of saddle emboli in this case led to severe atrophic changes, coldness, peripheral cyanosis on the both lower extremities, and flexion deformity on the knee and ankle joint of the left lower extremity. We planned staged operation for the saddle block and for mitral stenoinsufficiency and tricuspid insufficiency, because of poor general condition of the patient. The thromboembolectomy of aortic bifurcation was performed through the transabdominal approach without trial of Fogarthy catheter embolectomy, because of expectation of the secondary inflammatory changes of the vessel wall and thrombi which was 3 cm X 1 cm X 0.5 cm in size with irregular surfaced solid in consistency. 1 month later, after thromboembolectomy, mitral valve replacement and tricuspid annuloplasty were performed, with successful early operative result. During operation organized thrombi [1 cm X 0.5 cm] in the left auricle was removed. We wonder if simple management using Fogarthy catheter might be possible to remove the thromboemboli instead of thromboembolectomy by aortotomy in this case.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.5
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• pp.622-632
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• 2005

Statement of problem: Silicone Index Tooth Tray impression system which does not use gingicord has a shortcoming. It takes time to remove internal wall of Silicone Index Tooth Tray for space of wash impression material. Purpose: This study was to evaluate whether providing certain space to impression body can prevent from doing complicated laboratory work. Material and methods: After mounting metal dies with shoulder and chamfer margins arbiturarily, SITT was produced using $Blu-mousse^(R)$. In one experimental group, wash impression was taken using $Fit-tester^(R)$ without removing interior surface of SITT and in the other group, wash impression was taken using $Fit-tester^(R)$ providing 0.5mm space in the SITT and then compared the differences in two groups. Results: 1. There was no significant difference between a group which did not allow space and a group which granted equal 0.5mm space. 2. There was no significant difference between gingival diameter, occlusal diameter of metal die that has shoulder margin and gingival diameter, occlusal diameter of metal die that has chamfer margin. 3. There was no significant difference between a group which did not take pick-up impression and a group which took pick-up impression through relining method using SITT 4. There was no significant difference between a group that poured immediately after taking primary impression and a group that poured after removing poured stone die. Conclusions: When taking an impression of an abutment using SITT impression system, it is considered to obtain clinically identical results between a group that did not grant a 0.5mm space within SITT for wash impression and a group which invest a space. Furthermore, it is considered possible to produce an individual die through secondary pouring.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.104-104
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• 1999

The local heat transfer coefficient is experimentally investigated for the reflux condensation in a countercurrent flow between the steam-air mixture and the condensate. A single vertical tube has a geometry which is a length of 2.4m, inner diameter of 16.56mm and outer diameter of 19.05mm and is made of stainless steel. Air is used as a noncondensible gas. The secondary side is installed in the form of coolant block around vertical tube and the heat by primary condensation is transferred to the coolant water. The local temperatures are measured at 15 locations in the vertical direction and each location has 3 measurement points in the radial direction, which are installed at the tube center, at the outer wall and at the coolant side. In three different pressures, the 27 sets of data are obtained in the range of inlet steam flow rate 1.348 -3.282kg/hr, of inlet air mass fraction 11.8 -55.0%. The local heat transfer coefficient increases as the increase of inlet steam flow rate and decreases as the decrease of inlet air mass fraction. As an increase of the system pressure, the active condensing region is contracted and the heat transfer capability in this region is magnified. The empirical correlation is developed represented with the 165 sets of local heat transfer data. As a result, the Jacob number and film Reynolds number are dominant parameters to govern the local heat transfer coefficient. The rms error is 17. 7% between the results by the experiment and by the correlation.

• Journal of the Korean Wood Science and Technology
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• v.15 no.2
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• pp.79-89
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• 1987

This study was executed to examine helical structure and other feature, of Taxus cuspidata S. et Z. and Larix gmelinii var. principis-ruprechtii Pilger through photomicroscopic and scanning electron microscopic observation, and the obtained result, were summarized as follows: 1. Tracheid transition from springwood to summerwood was abrupt, mel slightly gradual in Taxus cuspidata S. et Z. and summerwood width of Larix gmelinii var. principis-ruprechtii Pilger was wider than that of Taxus cuspidata S. et Z. 2. Normal vertical and horizontal resin canals and surrounding thick epithelial cells were present in Larix gmelinii var. principis-ruprechtii Pilger but not present in Taxus cuspidata S. et Z. 3. Instead of helical thickening, helical chicks were observed only in summerwood trachieds of Larix gmelinii var. principis-ruprechtii Pilger. However, helical thickenings forming S, Z., and horizontal helix perpendicular to long axis of tracheid were observed in springood and summerwood tracheids of Taxus cuspidata S. et Z. and these helical thickenings were considered as analogous to the innermost layer of secondary wall. 4. Uniseriate and fusiform rays were appeared on tangential surface of Larix gmelinii var. principis-ruprechtii Pilger but oly uniserate ray was observed on tangential surface ot Taxus cuspidata S. et Z. The fusiform rays of Larix gmelinii var. principis-ruprechtii Pilger usually contained one horizontal resin canal bot occasionally two horizontal resin canals were contained in a fusiform ray. 5. Trabeculae and crassulae were observed in the tracheids of Larix gmelimii var. principis-ruprechtii Pilger but not observed in the tracheids of Taxus cuspidata S. et Z.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.7
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• pp.937-944
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• 1999

The near-wall flow structures of turbulent boundary layer over riblets having semi-circular grooves were investigated experimentally for the drag decreasing ($s^+=25.2$) and drag increasing ($s^+=40.6$) cases. The field of view used for tho velocity field measurement was $6.75{\times}6.75mm^2$ in physical dimension, containing two grooves. One thousand instantaneous velocity fields over the riblets were extracted for each case of drag increase and decrease. For comparison, five hundreds instantaneous velocity fields over a smooth flat plate were also obtained under the same flow conditions. To see the global flow structure qualitatively, the flow visualization was also performed using the synchronized smoke-wire technique. For the drag decreasing case ($s^+=25.2$), most of the streamwise vortices stay above the riblets, interacting with the riblet tips. The high-speed in-rush flow toward the riblet surface rarely influences the flow inside tho riblet valleys submerged in the viscous sublayer. The riblet tips seem to impede the spanwise movement of the longitudinal vortices and induce secondary vortices. The turbulent kinetic energy in the riblet valley is sufficiently small to compensate the increased wetted area of the riblets. In addition, in the logarithmic region, the turbulent kinetic energy are small or almost equal to that of a smooth flat plato. For the drag increasing case ($s^+=40.6$), however, the streamwise vortices move into the riblet valley freely, interacting directly with the riblet inner surface. The penetration of the high-speed in-rush flow on the riblets increases tho skin-friction. The turbulent kinetic energy is increased in the riblet valleys and even in the outer region compared to that over a flat plate.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.2
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• pp.256-268
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• 1999

Submerged implants require secondary surgical uncovering of implants after healing period of 3-6 months. In surgical methods, there are surgical scalpel, tissue punch, electro-surgical, and laser-used uncovering, and so forth The objectives of this study are investigation and assessment of 1) thermal change in clinical application for uncovering of HA-coated implant and pure titanium implant irradiated by pulsed Nd-YAG, $CO_2$, and Er-YAG laser. 2) surface change of cover screws aaer irradiation using laser energy. The temperature of apex & side wall of implants were recorded at 10sec, 20sec, 30sec after 30sec irradiation to implant healing screw; 1) pulsed Nd-YAG laser; 2W, 20pps, contact mode 2) $CO_2$ laser; water-infused & non-water infused state, 2.5-3.5W, contibuous mode, noncontact mode 3) $CO_2$ laser ; non-water infused state, 3W, superpulse, noncontact. mode 4) Er-YAG laser; (1) non-water infused state, 10pps, 60mj, contact mode (2) water-infused state, 10pps, 60mj, 80mj, 101mj, contact mode. According to the results of this study, pulsed Nd-YAG laser is not indicated because of increased thermal change and pitting of metal surface of implant cover screw. By contrast, $CO_2$ laser & Er-YAG laser are presumed to indicate because of narrow range of thermal change & near abscence of thermal damage of metal surface. Dental laser is thought to be much helpful to surgical procedure when it is used as optimal power and time condition considering characteristics and indications of each laser. Further research is needed to verify that these techniques are safe and beneficial to implant success.

• Journal of Ginseng Research
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• v.44 no.1
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• pp.161-167
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• 2020

Background: The ascomycete fungi Cylindrocarpon destructans (Cd) and Fusarium solani (Fs) cause ginseng root rot and significantly reduce the quality and yield of ginseng. Cd produces the secondary metabolite radicicol, which targets the molecular chaperone Hsp90. Fs is resistant to radicicol, whereas other fungal genera associated with ginseng disease are sensitive to it. Radicicol resistance mechanisms have not yet been elucidated. Methods: Transcriptome analyses of Fs and Cd mycelia treated with or without radicicol were conducted using RNA-seq. All of the differentially expressed genes (DEGs) were functionally annotated using the Fusarium graminearum transcript database. In addition, deletions of two transporter genes identified by RNA-seq were created to confirm their contributions to radicicol resistance. Results: Treatment with radicicol resulted in upregulation of chitin synthase and cell wall integrity genes in Fs and upregulation of nicotinamide adenine dinucleotide dehydrogenase and sugar transporter genes in Cd. Genes encoding an ATP-binding cassette transporter, an aflatoxin efflux pump, ammonium permease 1 (mep1), and nitrilase were differentially expressed in both Fs and Cd. Among these four genes, only the ABC transporter was upregulated in both Fs and Cd. The aflatoxin efflux pump and mep1 were upregulated in Cd, but downregulated in Fs, whereas nitrilase was downregulated in both Fs and Cd. Conclusion: The transcriptome analyses suggested radicicol resistance pathways, and deletions of the transporter genes indicated that they contribute to radicicol resistance.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.589-602
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• 1998

Mt. Nam (265m), a city park of Seoul, was originally covered with a typical deciduous broad-leaved forests in Central Korea. However, the park forests have been changed the development for various purpose such as the construction of castle wall, road way, broadcasting station, theater, hotel and apartments, in addition, to thoughtless plantation or alien plant introduction. Human population growth from ca. 100 thousands persons less in that time established Seoul as the capital of choseon dynasty in 1394 to ten millions over persons at present, accelerated the vegetational changes of the park. mt. Nam boundary in those days of sunjong (1908) also was much shrinked as much the range of 300 m distance in the northern most to 700 or 800m distance in some places. The actual vegetation of Mt. Nam largely can be classified by floristic composition into two plant communities of Quercus mongolica community and Pinus densiflora community, four plantations of Pinus rigida, Robinia pseudo-acacia, Populus tomentiglandulosa and other tree species, and on mixed forest with native and alien tree species in secondary succession stage (Yim et al. 1987). The restoration movement of Mt. Nam toward to the natural condition of forest or biodiversity is moving now. However, in the movement there are some problems such as the lack of ecological consideration and the undesirable decision of priority in the practice. A warning should be given, especially, on the undesirable plantation of non-native tree species restricting the forest succession, as in the case of southern slope of Mt. Nam. First of all, the most importance in Mt. Nam management is that the restoration for natural forest and biodiversity should be carried on the basis of integrated ecological principles based on the site evaluation.