• Nuclear Engineering and Technology
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• v.56 no.11
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• pp.4620-4627
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• 2024

We introduce a novel fast-reciprocating probe head installed on the EAST (Experiment Advanced Superconducting Tokamak) containing 12 graphite tips. This allows us to measure a variety of plasma parameters such as the plasma density, temperature, and space potential in the scrape-off layer (SOL). We will also acquire the data at high frequency thus measuring the ion saturation current, I_sat, and the floating potential, V_f, average and fluctuating values. Moreover, with poloidally separated tips, we measure the poloidal electric field, E_θ, at two toroidal locations, assuming a plasma flow dominated by the E×B drift this leads to the determination of the radial velocity. As a consequence, the turbulent radial flux will thus be determined. In the parallel direction, we have four tips that are aligned parallel with the magnetic field lines, thus making an angle of 4°24' to the horizontal direction. This unique design should allow the measurement of the toroidal wavenumber, k_φ, a quantity rarely obtained in tokamaks. This new probe, with 7 tips for measuring the ion saturation current and 4 tips to measure the floating potentials, was used on the EAST during the 2023 summer campaign. We present the first experimental results obtained during an L-mode plasma.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.175-181
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• 2005

This work described some essential factors necessary for micro-propagation of banana for mass production of synthetic seeds for germ plasm conservation, and how peroxides activity of conserved tissue was influenced. Shoot tips of field grown plants were used to obtain shoot clusters on shoot proliferation medium (MS medium supplemented with 5 mg/l BAP). Using longitudinally-split shoot tip technique, 18720, 8640, 7488, 2016 plantlets were obtained from one shoot tip of Maghraby, Grand Naine, Balady, and Williams, respectively, in six subculture, one month each, on solid medium. Shoot tips excised from in vitro grown plantlets were encapsulated in calcium-alginate beads and stored at $4^{\circ}C$ for one month on half-strength MS basal medium without growth regulators or sugars. After one month all the viable-conserved synseeds formed shoots when they were transferred to MS basal medium, some of them showed synchronous formation of shoot and root systems in one week. Plants retrieved from encapsulated shoot tips were hardened off and transferred to soil.

• Journal of Plant Biotechnology
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• v.5 no.2
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• pp.101-105
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• 2003

To eradicate several viruses such as PVX, PVY, and PLRV which often cause considerable damages to the growth and yields of potatoes, several stems including shoot tips were excised from the potato plants grown for 50 days and electric shock was treated. Shoot tips excised from electric-shocked stems were transferred into the medium supplemented with antiviral compound, ribavirin to examine the combinatorial effect. When treated only with 20 mg/L ribavirin, PVX concentration in the regenerated plant-lets was slowly decreased as repeating sub-culture and finally, it took 32 weeks to reach completely PVX-free stock. With an electric shock treatment (10 mA electric current), all the replicates became free from PVY. However, PLRV was not completely eradicated from 94P70-4 and 93P29-3 lines even by treating with 10 mA electric shock. In this case, both electric shock and antiviral compound treatments in axillary buds from the stem segment were successful in eradicating viral contamination.

• Horticultural Science & Technology
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• v.16 no.4
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• pp.520-524
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• 1998

This study was carried out to investigate the effect of thidiazuron(TDZ) on callus and shoot primordia formation, to determine the most optimum multiple shoot induction medium, and to obtain the plantlets on solid medium via shoot organogenesis. TDZ 0.01 mg/L in MS medium was most effective on callus formation, and BA 0.1 mg/L was most effective on shoot growth, while TDZ 0.01 mg/L was most effective on callus formation. TDZ 0.001 mg/L was most effective in shoot primordia formation. Shoot tips were cultured with TDZ 0.01 mg/L for 8 weeks and induced callus was transferred to regeneration medium containing TDZ 0.001 mg/L. After 4 weeks induced shoot primordia were resubcultured at growth regulator-free medium for 4 weeks. The induced multiple shoots rooted more efficiently at NAA 1.0, 5.0 mg/L, or IBA 5.0 mg/L.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.281-285
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• 2005

To establish the mass proliferation system of Ardisia pusilla DC, the shoot tips of Ardisia pusilla DC were cultured on the MS and half-strength MS medium supplemented with $0{\sim}5.0$ mg/L BA or $0{\sim}0.5$ mg/L thidiazuron(TDZ), respectively. A few multiple shoot formation observed when the shoots were cultured on MS medium containing TDZ. However, the frequency of multiple shoot formation was reached up to 82.4%, when the shoots were cultured on half-strength MS medium supplemented with 0.5 mg/L BA. Also the number of shoot per explant was 7.1. To promote rooting from multiple shoot, newly formed shoots were transferred to half-strength MS medium containing 0.5 mg/L IBA or 0.5 mg/L NAA, respectively. Regenerated plantlets were grown to normal mature plants in soil.

• Journal of Ginseng Research
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• v.38 no.1
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• pp.73-77
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• 2014

Field and nutrient cultures of American ginseng (Panax quinquefolius L.) were used to establish foliar symptoms related to boron (B) concentration in leaves and soils, and to evaluate radish as a time-saving model system for B nutrition. Application of excess B, 8 kg/ha versus the recommended 1.5 kg/ha, to field plantings of 2-, 3-, and 4-yr-old American ginseng plants just prior to crop emergence caused, within 4 wk after crop emergence, leaf symptoms of chlorosis followed by necrosis starting at the tips and progressing along the margins. The B concentration in leaves of 2-4-yr-old plants receiving 1.5 kg/ha Bwas $30{\mu}g/g$ dry mass compared to $460{\mu}g/g$ dry mass where 8 kg/ha B was applied. Similarly, B concentration in soils receiving the lower B concentration was 1.8 mg/g dry mass and $2.2-2.8{\mu}g/g$ dry mass where the higher B concentration was applied. Application of 8 kg/ha B reduced the dry yield of 3rd-yr roots by 20% from 2745 kg/ha to 2196 kg/ha and 4th-yr roots by 26% from 4130 kg/ha to 3071 kg/ha. Ginseng seedlings and radish were grown under greenhouse conditions in nutrient culture with four B concentrations ranging from 0 mg/L to 10 mg/L. At 5 mg/L and 10 mg/L ginseng and radish developed typical leaf B toxicity symptoms similar to those described above for field-grown plants. Increasing B in the nutrient solution from 0.5 mg/L to 10 mg/L decreased, in a linear fashion, the root and leaf dry mass of ginseng, but not radish. Given the many similarities of ginseng and radish to B utilization, radish might be used as a timesaving model system for the study of B, and other micronutrients, in the slow-growing perennial ginseng.

• Journal of Plant Biotechnology
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• v.35 no.3
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• pp.203-208
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• 2008

In order to micropropagate uniform plantlets of Philodendron cannifolium in vitro, the shoot tips were cultured on MS media supplemented with $0.5{\sim}10.0$ mg/L BA or $0.05{\sim}0.1$ mg/L thidiazuron(TDZ). The adventitious multi-bud clusters from basal part of shoots were formed on MS media containing $2.0{\sim}5.0$ mg/L BA or $0.05{\sim}0.1$ mg/L TDZ. But the shoots grown on MS media with TDZ showed necrosis by the lack of chlorophyll. The adventitious multi-bus clusters were cut into $5{\sim}7$ mm sections and cultured on MS media containing BA and TDZ for shoot proliferation. Shoots were proliferated vigorously on MS medium supplemented with $1.0{\sim}3.0$ mg/L BA with up to 30 shoots. But abnormally swollen hard calli were formed from basal parts of shoots on MS media with TDZ and high concentration of BA(10.0 mg/L). The proliferated shoots on same media also showed necrosis by the lack of chlorophyll. The shoot growth and rooting were favorable on MS media containing $0.5{\sim}2.0$ mg/L IBA. The rooted plantlets were acclimatizated effectively in soil mixed with perlite 1:vermiculite 1 or vermiculite alone. Fifteen mL of liquid medium containing 10 g/L activated charcoal and 30 g/L sucrose were added in same vessels after small shoots were proliferated to stimulate shoot growth and rooting. After 8 weeks in culture, the shoots were dipped into high concentration of IBA solution. and planted in soil mexed with perlite 1:vermiculite 1. The shoot growth and rooting were favorable in dipping treatments of $500{\sim}2,000$ ppm IBA solutions for 10 sec.

• Korean Journal of Plant Tissue Culture
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• v.24 no.1
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• pp.53-55
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• 1997

The shoot tips of Delphinium cv. Princess Caroline were cultured on the MS medium supplemented with cytokinin and auxin alone or in combination. Among cytokinins, BA was most effective in shoot multiplication, adequqte concentrations being 1.0-5.0 mg/L. Shoot multiplication was very favorable on the media with 1.0-3.0 mg/L BA and 0.1-0.5 mg/L IAA. Additions of BA and IAA did not stimulate shoot multiplication, but increased a little fresh weight. Shoots were scarcely rooted on the media with IBA or NAA, and were not done utterly on the media containing activated charcoal. Therefore, shoots were treated by Rootone and planted in the cultural media for in vivo rooting. The highest rate of rooting was 68% in the mixed cultural medium composed of Perlite 1 and Vermiculite 1.

• Journal of Plant Biotechnology
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• v.6 no.2
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• pp.77-85
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• 2004

Development of efficient plant regeneration and genetic transformation protocols (using the Particle Inflow micro-projectile Gun and the shoot-tips as target tissue) of Sorghum bicolor (L.) Moench in terms of expression of the reporter gene, $\beta$-glucuronidase(uidA) is reported here. Two Indian cultivars of sorghum were used in the study, viz. M-35-1 and CSV-15. Plant regeneration was achieved from one-week-old seedling shoot-tip explants via multiple-shoot-clumps and also somatic embryos. The multiple-shoot-clumps were produced on MS medium containing BA (0.5, 1.0 or 2.0 mg/$L^{-1}$), with biweekly subculture. Somatic embryos were directly produced on the enlarged dome shaped expansive structures that developed from shoot-tip explants (without any callus formation) when cultured on MS medium supplemented both with BA (0.5, 1.0 or 2.0 mg/$L^{-1}$) and 2,4-D (0.5 mg/$L^{-1}$). Whereas each multiple-shoot-clump was capable of regenerating more than 80 shoots via an intensive differentiation of both axillary and adventitious shoot buds, the somatic embryos were capable of 90% germination, plant conversion and regeneration. The regenerated shoots could be efficiently rooted on MS medium containing 1.0mg/$L^{-1}$ IBA and successfully transplanted to the glasshouse and grown to maturity with a survival rate of 92%. The plant regeneration efficiency of both the genotypes were similar. After the micro-projectile bombardment, expression of uidA gene was determined by scoring blue transformed cell sectors in the bombarded tissue by an in situ enzyme assay. The optimal conditions comprising a helium pressure of 2200 K Pa, the target distance of 11 cm with helium inlet fully opened and the use of osmoticum have been defined to aid our future strategies of genetic engineering in sorghum with genes for tolerance to biotic and abiotic stresses.

• Korean Journal of Plant Resources
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• v.12 no.4
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• pp.253-259
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• 1999

In this study, three simple methods were established to confirm the transgenic potato plants. The leaf disc was used in the first method. After leaf discs of transgenic and non-transgenic potato were transfered into the liquid MS medium with bialaphos 5mg/l, 25 days, the chlorosis occurred in the non-transgenic leaf discs while it could not find in the transgenic leaf discs, In the second method, shoot tips of potato were transferred into MS medium supplemented with 0.5mg/l bialaphos and 0.6% agar. After 7-10 days, a lot of roots developed from the transgenic shoot tip, but the non-transgenic shoot tip was dead. The third method was using chlorophyll contents. Leaf discs were transferred into the liquid MS medium with bialaphos 0.5 mg/l. After 15 days, the content of chlorophyll A in transgenic plant was at least 2.5 times higher than in non-transgenic plant. In addition, the PAT enzyme activity were detected in the transgenic potato, but not detected in normal potato.