• Journal of the Korean Wood Science and Technology
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• v.12 no.4
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• pp.31-35
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• 1984

These experiments were carried out to investigate anatomical properties of Forsythia in Korea. The results obtained were summarized as follows: It was estimated that the vessel of cross section was almost simple pore and multiple pores which were compounded two or three units were showed sometimes and arrangement of vessel were ring porous wood. In the mean length of vessel, Forsythia koreana was ranged $539.98{\pm}154.71{\mu}$ and Forsythia ovata $602.22{\pm}157.38{\mu}$ and Forsythia nakaii T. Lee $465.50{\pm}83.02{\mu}$. In the mean length of fiber wood, Forsythia koreana $387.40{\pm}68.23{\mu}$, and Forsythia ovata was $533.90{\pm}106.77{\mu}$ and Forsythia nakaii T. Lee was $482.40{\pm}72.33{\mu}$. The type of Ray parenchyma was heterogeneous ray I tissue. The mean length of procumbent ray cell in the radial section was $42.14{\pm}8.30{\mu}$ and that of rectangle type in up right ray cell was $45.76{\pm}7.19{\mu}$ and that of square type was $26.66{\pm}2.99{\mu}$. The mean height of ray parenchyma in the tangential section was $174.80{\pm}37.51{\mu}$ and the width of ray parenchyma was $17.25{\pm}3.59{\mu}$ and the mean number of ray parenchyma was $14{\pm}3$.

• Journal of Plant Biotechnology
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• v.6 no.1
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• pp.1-7
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• 2004

Forestry sector has witnessed some unprecedented events in the recent past both in terms of galloping biotechnological developments and heated environmental debates over risks associated with release of transgenic trees. Improvements in the in vitro propagation techniques has made it possible to develop tissue culture based plant regeneration protocols just for about any tree species. And with the inclusion of every new species within the realms of tissue culture technology, it becomes a candidate for genetic improvement through recombinant DNA technology, the so called genetic engineering. Poplars and their hybrids serve as the model tree species on which most of the genetic transformation work as been carried out. A lot of work has also gone in genetic transformation of fruit trees and trees of horticultural interests. Trees have been successfully transformed for traits ranging from reduction of length of juvenile phase to alteration of tree architecture to altering wood quality by lignin and cellulose modification. More-over trees have been genetically engineered successfully to combat various types of insect pests and pathogens causing diseases. But all these developments have ignited controversies over the possible benefits and risks associated with transgenic plantations by various environmental agencies and activists. Solutions to most of these concerns can be found out with more intensive prioritized research.

• Nuclear Engineering and Technology
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• v.8 no.3
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• pp.139-143
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• 1976

$^{32}$ P was supplied to the roots of stem-ringed 1-year-old apple trees and 2-year-old citrus trees on which bark segments were isolated above and below the ring. $^{32}$ P was translocated to shoots and leaves although considerable translocation occurred especially in wood and bark tissues. The accumulation of $^{32}$ P in isolated bark segments indicated that the occurrence of these materials in this tissue was via radial translocation from xylem tissue, and that the main upward translocation pathway of $^{32}$ P supplied to roots is through the xylem.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.1
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• pp.18-24
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• 2018

Objectives: Foreign bodies (FBs) account for 3.8% of all pathologies of the head and neck region, and approximately one third of them are missed on initial examination. Thus, FBs represent diagnostic challenges to maxillofacial surgeons, rendering it necessary to employ an appropriate imaging modality in suspected cases. Materials and Methods: In this cross-sectional study, five different materials, including wood, metal, glass, tooth and stone, were prepared in three sizes (0.5, 1, and 2 mm) and placed in three locations (soft tissue, air-filled space and bone surface) within a sheep's head (one day after death) and scanned by panoramic radiography, cone-beam computed tomography (CBCT), and ultrasonography (US) devices. The images were reviewed, and accuracy of the detection modalities was recorded. The data were analyzed statistically using the Kruskal-Wallis, Mann-Whitney U-test, Friedman, Wilcoxon signed-rank and kappa tests (P<0.05). Results: CBCT was more accurate in detection of FBs than panoramic radiography and US (P<0.001). Metal was the most visible FB in all of modalities. US was the most accurate technique for detecting wooden materials, and CBCT was the best modality for detecting all other materials, regardless of size or location (P<0.05). The detection accuracy of US was greater in soft tissue, while both CBCT and panoramic radiography had minimal accuracy in detection of FBs in soft tissue. Conclusion: CBCT was the most accurate detection modality for all the sizes, locations and compositions of FBs, except for the wooden materials. Therefore, we recommend CBCT as the gold standard of imaging for detecting FBs in the maxillofacial region.

• Journal of Life Science
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• v.8 no.4
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• pp.443-448
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• 1998

We analyzed lignin content and wxpression of OMT gene during growth season in two hybrid poplar species. OMT gene expression was observed mainy in the developing secondary xylem where major quantity of lignin occurs. Lignin content in the xylem tissue increased as plant resumed growth in the spring and reached the highest in the late August. Change in lignin content was concurrent with that of OMT gene expression, indicating OMT is a key enzyme in lignin biosynthesis.

• Journal of the Korean Wood Science and Technology
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• v.15 no.3
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• pp.14-23
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• 1987

This study was carried out to investigate the anatomical characteristics, the radial and axial variation of the cell dimension and bulk density for four bamboo species used as the major material of bamboo products in Korea; Phyllostachys(P.bambusoides, P.edulis, P.nigra var.henonis, and Pnigra). The results obtained were summarized as follows; 1) In the outer part of culm, the mophological difference of cell diameter and distribution were not acknowledged. However, gum-like substance was occurred In the epidermis, hypodermis, cortex and metaxylem vessel of P.nigra, while it was occured only in the metaxylem vessel of P.edulis. 2) The protoxylem vessel in the central zone of culm-wall could be in the two types; the first type consisted of 4-5 small cell pieces occurred in P.edulis and P.nigra var. henonis, the second type of 1-2 large cell pieces in P.bambusoides and P.nigra. And transition of cell diameter from the vascular bundle sheath to the ground tissue was gradually enlarged in P.nigra and P.edulis but abruptly in P.bambusoides and P.nigra var. henonis. 3) Thin-wall tyloses were well developed in the outer and central zone of culm-wall in four species. 4) Compared with the central part of culm-wall, the number of parenchyma cells and the amount of the vascular bundle sheaths per unit area were a few in the inner part. The inner part nearest to the pith cavity was consisted of thick-well parenchyma cell. 5) The dimensional variations of metaxylem vessel and parenchyma cell in the radial direction were decreased from the inner part to the epidermis in all species observed. 6) The fiber length was the maximum in the central zone and its diameter was increased from the inner part to the outer part. In the axial variation. fiber length was slightly increased from the base and then decresed slowly toward the top, and its diameter was reverse. 7) The axial variation of the bulk density was continuously increased from the base toward the top and its radial variation was rapidly increased from the inner part to the epidermis.

• Journal of the Korean Wood Science and Technology
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• v.21 no.4
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• pp.45-54
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• 1993

This study examines the differences in structures, physical and mechanical properties between domestic(Quercus variabilis Blume) and foreign(Quercus suber L.) corks. The results obtained are as follows: 1. The cork tissue consists of cork cells, lenticels, sclereids and dark-brown zone. There was a significant difference in ratio of cork cells between foreign cork(93 %) and domestic cork(87 %). The ring width and width of late cork of the foreign cork were wider than those of domestic cork. But the percentage of late cork of domestic cork was richer than that of foreign cork. The size of cork cell of foreign cork was larger by about two times than that of domestic cork. 2. The density was slightly higher in domestic cork(0.22 g/$cm^3$) than in foreign cork(0.19 g/$cm^3$). During first 24 hours, the amount of water absorption of the foreign cork was greater than that of domestic cork. However, after 24 hours, the tendency was reversed. The level of EMC was higher in domestic cork than in foreign cork. Total shrinkage in the radial and tangential directions was larger in domestic cork than tn foreign cork. In the longitudinal direction, the tendency was reversed. There was no difference in total swelling in three woody directions between the two corks. 3. The modulus of elasticity in compression in the logitudinal and tangential direction was higher in domestic cork than in foreign cork, but the tendency was reversed in the radial direction. Both corks showed 95% of recovery rate after 24 hours when they were compressed by 0.5. There were no differences in tension strength and Brinell,s hardness bet ween domestic and foreign corks.

• Archives of Craniofacial Surgery
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• v.24 no.1
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• pp.37-40
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• 2023

Penetrating wounds to the face are cosmetically devastating and can be life-threatening. If the foreign body causing the penetrating wound is a piece of wood, small remnants might be left behind after the initial treatment. A 33-year-old male patient presented to the emergency center after a piece of lumber pierced his face as a passenger in a traffic accident. The patient's vital signs were stable, and emergency surgery was performed to remove the foreign body and repair the soft tissue. No noteworthy complications were seen after open reduction and internal fixation of the facial bone fractures. Seven months after the accident, the patient underwent scar revision along with full-thickness skin grafting for post-traumatic scars. After the surgery, pus-like discharge which was not previously present was observed, and the graft did not take well. A residual foreign body, which was the cause of graft failure, was found on computed tomography and the remaining foreign body was removed through revision surgery. The patient is receiving outpatient follow-up without any complications 6 months after surgery. This case demonstrates the importance of performing a careful evaluation to avoid missing a residual foreign body, especially if it is of wooden nature.

• Korean Journal of Heritage: History & Science
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• v.47 no.4
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• pp.58-73
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• 2014

In general, it is thought discoloration on wood is frequently found in decorative wood products. So this study was conducted focusing on white rot found lower parts of columns and baseboards of a wooden house, Hyunchungsa (shrine) to know whether microorganisms have any influence on discoloration or there is correlation with strength by investigating resistograph, occurrence of microorganisms and microscopy for analysis(SEM, tissue analysis etc.). The results obtained were as follows: (1) The result of measurement of resistograph showed there are little correlation between discoloration and strength though there was a spot indicating low resistance. (2) The moisture content of discolored part was relatively higher than that of normal parts, but occurrence of microorganisms was less in discolored parts while more kinds of microorganisms were identified in normal parts with high CFU(Colony Forming Unit). (3) The result of SEM (with a magnification of 500 times) on the surface of discolored parts, it was found out there are many kinds of particles in different sizes on the surface and those were composed of elements such as C, O, Si, Ca, and a small amount of Na and Cl (weight %) were detected in part. (4) The result of tissue analysis showed discoloration occurs limitedly to the outer surface of column. As these results, it is concluded that discoloration has nothing to do with strength, damage by microorganisms and salt.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.45-50
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• 2008

This study was carried out to investigate the promoting effect of wood flour on the mycelial growth of Lentinus lepideus and Lentinus edodes. To determine the optimal culture condition, we first examined the tissue origin of pine flour (Pinus densiflora) including needle, bark, root and xylem. Only the xylem-derived flour increased mycelial growth compared to no treatment control. The addition of the xylem flour (5 g/l) showed the highest increase and the glucose level in the basal medium was best at 10 g/l. The smaller particle size of the xylem flour showed the positive effect on mycelial growth; two-fold increase when supplemented with flour of which particle size is less than $106\;{\mu}m$ in diameter compared to $425\;{\mu}m$. The addition of the xylem flour continuously increased the mycelial production for 25 days while mycelia stopped growing within 15 days without the xylem flour. In addition, when woody flour obtained from the different tree species was applied to L. edodes mycelial culture, all treatments accelerated mycelial production compared to the control. Based on all results described above, we conclude that the supplementation of woody flour to culture medium may be an another promising way to increase mycelial production of economically important fungi.