• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.65-70
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• 1999

This study was conducted to develop a simple selection method for herbicide-resistance weeds. Two methods, designated "seedling method" and "stem node method" were employed for screening of barnyardgrass against propanil and butachlor. In the seedling method, shoot and root growth of barnyardgrass were significantly inhibited at quarter of the recommended herbicide rate, while in the stem node method, the similar inhibition was obtained at half of the recommended rate. Thus, it was concluded that the seedling method is more simple and quick method to evaluate response of barnyardgrass to propanil and butachlor compared to stem node method.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.245-248
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• 1997

Excessive stress on the bone-stem interface may cause local micromotion that could produce midthigh pain, interface bone resorption and prevent bony ingrowth. It is important for clinician and prosthetic designer to develop an understanding of the load transfer mechanism, its associated stress pattern and its relationships with the particular mechanical characteristics of the femoral stem designs. Finite element method (FEM) is preeminently suited to provide information in this respect. The authors developed 3-dimensional numerical finite element models implanted with the straight stem which is composed of total 1170 elements of 8 nodes and with the curved stem which is composed of total 885 elements of 8 node, and analysed the relative micromotions between the straight stem and the curved stem in immediate postoperative stage of an uncemented total hip replacement in load simulating the single leg stance. The results showed that the rotational displacement was occupied over 90% of total micromotion in both types of stem and was peak at the proximal medial portion of the stem, but markedly less distally. The curved stem was more stable especially in terms of rotational stability. It is recommended that surgeons do not allow the patient weight bearing until bony ingrowth was achieved. In the future more attention should be drawn to increase initial rotational stability of the two types of femoral stem to prevent loosening from excessive micromotion.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.704-709
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• 1996

This experiment was carried out to establish the system of mass propagation through tissue culture using sucker and stem in Ramie. The sterilization for tissue culture of Ramie was the better treatment of 2% NaClO for 20 minute into ultrasonic cleaner than the others, and so rate of contamination was 3.3%, and it was able to produce 96% healthy plant. The effect of growth regulator was superior to mixed treatment of 0.02mg/$\ell$ NAA, 1.5mg/$\ell$ BA, 0.lmgmg/$\ell$ GA$_3$, which it was not formed callus and but produced 96% healthy plant. The effect of propagation was higher in culturing of the stem node than the sucker in cultural part, local variety than improved ones. The effect of acclimatization was superior to pretreatment of 30 minute after soaking in 100ppm NAA, transplanting on bed soil which mixed to ratio of vermiculite : soil : sand =1 : 2 : 1, the transplanted plants were grown all normal.

• Korean Journal of Medicinal Crop Science
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• v.25 no.2
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• pp.83-88
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• 2017

Background: This study was aimed to determine the optimal vine induction method for growing of Korean schisandra (Schisandra chinensis), by comparing plant growth and fruit yields between plants grown with either fence-type (U-type) or A-type induction. Methods and Results: Plants were transplanted on August 17, 2014, and the plant height, stem node number and weight were measured every two weeks, six times from June 17, 2016. The plant height, stem node number, and leaf length and width were higher with the A-type than with the U-type induction, by approximately 37.0%, 49.1%, 27.6%, and 12.7%, respectively. Although there was no significant difference between the photosynthesis rates of plants grown with the two vine induction method, the leaf area and leaf number per plant were higher in the plants grown with the A-type than the U-type, by approximately 23.7% and 46.0%, respectively. The number of green-color pixels, in a defined area of digital camera images of creeper leaves from the inducted vines, was significantly higher in the plants grown with the A-type than the U-type. The number of fruit clusters per plant was approximately 26 and 36, under the U-type and A-type, respectively. A two fold higher total fruit weight per plant was observed in the plants grown under the A-type (250 g/plant) than the U-type (120 g/plant). Conclusions: The A-type vine induction method is optimal for cultivation of Korean schisandra.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.162-167
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• 2016

This study was carried out to investigate proper stem cutting position and air temperature to regenerate roots from cuttings of bitter gourd. 'NS454' (NS) and 'Dragon' (DR) cultivars were tested and the cutting position was cut at the 3rd node in the stem (treatment I) and cut at the central part (stem segment) between 3rd leaf and 4th leaf in the stem (treatment II). The air temperature was maintained at 18, 23, 28 and $35^{\circ}C$ in the growth chambers, respectively. The photosynthetic photon flux at the ground of a chamber was maintained in approximately $150-200{\mu}mol\;m^{-2}s^{-1}$ during the 16-hour photoperiod. The relative humidity in the chambers was maintained over 85%. After 10 days of cuttings, regardless of cutting position, DR and NS cultivars showed 100% the survival rate in the $18^{\circ}C$ or $23^{\circ}C$ treatments, however, most of plants $18^{\circ}C$ treatment had not rooting. In the $28^{\circ}C$ treatment, regardless of cutting position, DR and NS cultivars showed 100% of the rooting rate. In the $23^{\circ}C$ treatment, for DR cultivar, the node cutting showed 90% of rooting rate and the stem segment cutting showed 40% rooting rate. For NS cultivar, the node cutting showed 50% of rooting rate and the stem segment cutting showed 40% rooting rate. DR and NS cultivars have high rooting rate, while the rooting rate remarkably decreased in the $35^{\circ}C$ treatment. For DR cultivar, the stem segment cutting showed 5.3 of the highest rooting number and the node cutting showed 2.7 rooting number in the $28^{\circ}C$ treatment. NS cultivar was not significantly different the rooting regardless of cutting position. The results suggested that cutting at the stem segment cutting of bitter gourd is an effective cutting method for increasing survival rate and the air temperature should be maintained at $28^{\circ}C$.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.246-250
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• 1995

Scions from the one- and two-years old and the nodes of Ligusticum chuanxiong stem were used to study the rooting ability with the treatment of plant growth regulators planted to different bed soils as the alternative propagation for the present method by rhizome. The rooting ratio in the scion from the one- and the two-years old plants showed any difference, but that was ranged from 94% to 100% in the first node and from 56% to 64% in the second node from the bottom of the stem. The scion of first node from both the plants showed more than 90% in the root ratio and 16 in the number of rooting and growed more than 31cm in the root length. The Rootone-F and 250ppm of NAA were most effective for the promotion of rooting. Rooting ratios in the sand and in the mixture of vermiculite and perlite as bed soils were about 18%, but that in the cultured soil considerably decreased.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.71-74
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• 1994

In cementless total hip arthroplasty(THA), an initial stability of the femoral component is mandatory to achieve bony ingrowth and secondary long term fixation. Bone ingrowth depends strongly on relative micromotion and stress distributions at the interface. Primary stability of the femoral component can be obtained by minimizing the magnitude of relative micromotions at bone-prosthesis interface, Hence an accurate evaluation of interface behavior and stress/strain fields in the bone implant system may be relevant for better understanding of clinical situations and improving THA design. However, complete evaluation of load transfer in the bone remains difficult to assess experimentally, Hence, recently finite element method (FEM) was introduced in orthopaedic research field to fill the gap due to its unique capacity to evaluate stress in structure of complex shape, loading and material behavior. The authors developed the 3-dimensional numerical finite element model which is composed of totally 1179 elements off and 8 node blick. We also analyzed the micromotions at the bone-stem interface and mechanical behavior of existing bone prosthesis for a loading condition simulating the single leg stance. The result indicates that the values of relative motion for this well fit Multilock stem were $150{\mu}m$ in maximum, $82{\mu}m$ in minimum, and the largest relative motion developed in medial region of proximal femur with anterior-posterior direction. The proximal region of the bone was much larger in motion than the distal region and the stress pattern shows high stress concentration on the cortex near the tip of the stem. These findings indicates that the loading in the proximal femoral bone in the early postoperative situation can produce micromotions on the interface and clinically cementless TEA patient should not be allowed weight bearing strictly early in the postoperative period.

• Tribology and Lubricants
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• v.13 no.1
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• pp.82-87
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• 1997

The modern orthopaedics frequently uses the total hip replacement in the artificial hip joint. The wear in this joint requires a re-replacement of hip joints because it is under the severe load and friction conditions. To solve these problems the previous studies have been mainly focussed on the development of new materials. The research of new materials, however, needs much time and effort since it should be experimented for its bio-compatibility, friction, and wear characteristics. To reduce the work, in this study, the finite element analysis is applied to find new combinations of bio-materials in the total hip replacement which has the excellent contact characteristics. A non-linear FEM program MARC with 5-node axisymmetric element was used for analyzing the contact stresses between the hip joints. The computed results show that in case of acetabulum UHMWP has good characteristics, in femoral head, $Al_2O_3$, and in stem, Ti6Al4V.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1996.10a
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• pp.189-194
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• 1996

The modern orthopaedics frequently uses the total hip replacement in the artificial hip joint. The wear in this joint requires the re-replacement of the hip joint beacuse it is under the severe load and friction conditions. To solve these problems the previous studies have been mainly focused on the development of the new materials. The research of new material, however, needs much time and effort since it should be experimented for its bio-compatibility, friction, and wear characteristics. To reduce the work, in this study, the finite element analysis is applied to find the new combination of the materials in the total hip replacement which has the excellent contact characteristics. The finite element uses MARC and the 5-node aximetric element. The results show that in case of acetabulum UHMWP has good characteristics, in femoral head, the $Al_2O_3$, and in stem, Ti6Al4V.

• Journal of Plant Biotechnology
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• v.6 no.3
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• pp.165-169
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• 2004

The fruits of Vitex rotundifolia in Korea, known as 'Man Hyung Ja', occupy an important position as traditional oriental medicine in Asian countries. It is known that propagation of this plant by seed is difficult and time-consuming with little success. Attempts were made to develop a method by using nodal culture techniques. Explants of stem node without leaves cultured on Nitsch medium containing 1 ml/L BA, gave the best shoot induction ratio. Also, BA with IAA or TDZ treatment showed positive effect on shoot induction. Half-strength Nitsch medium was supplemented with 0.5 mg/L NAA produced better success than did the others on root formation. It showed that many of the regenerants grew successfully on growth chamber at $24^{\circ}c$.