• Journal of Plant Biotechnology
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• v.37 no.4
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• pp.517-528
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• 2010

Rice seed maturation and germination involve drastic changes in water and nutrient transport, in which tonoplast aquaporins may play an important role. In the present study, gene expression profiles of 10 tonoplast intrinsic proteins (TIP) from rice were investigated by RT-PCR during seed development and germination. OsTIP3;1 and OsTIP3;2 were specifically expressed in mature seeds. Their transcript level rapidly decreased after onset of seed germination and gene expression was induced by ABA treatment. In contrast, expression of OsTIP2;1 and OsTIP4;3 was not seed specific as transcripts were found in vegetative tissues as well. Their respective transcript levels decreased at an early stage of seed development, whereas they increased at a later stage of seed germination and elongation of embryonic roots and shoots. When seed germination was inhibited by various stress conditions and ABA, expression of OsTIP2;1 and OsTIP4;3 was completely suppressed. In contrast, the expression level of OsTIP2;2 rapidly increased after seed imbibition and the transcript level was maintained under conditions inhibiting seed germination. These results implicate that tissue specific and developmental transcriptional regulation of OsTIPs in rice seeds depends on their specific function. In addition, OsTIPs can be discriminated by different potential phosphorylation and methylation sites in their protein structures. OsTIP3;1 and OsTIP3;2 possess unique phosphorylation signatures at their N-terminal domain, loop B and loop E, respectively. OsTIP2;1 and OsTIP4;3 have a potential methylation site at their Nterminal domain. This suggests that activity of specific tonoplast aquaporins may be regulated by post-translational modification as well as by transcriptional control.

• Journal of Plant Biotechnology
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• v.41 no.4
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• pp.180-193
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• 2014

In plants, a shoot apex has a small region known as the shoot apical meristem (SAM) having a group of dividing (initiating) cells. The SAM gives rise to all the groundabove structures of plants throughout their lifetime, and thus it plays important role in growth and development of plants. This review describes theories to explain the SAM organization and function developed over the last 250 years. Since in 1759 German botanist C. F. Wolff has described firstly the SAM, in 1858 Swiss botanist C. N${\ddot{a}}$geli proposed the apical cell theory from the observation of a large single apical cell in the SAM of seedless vascular plants: however, this view was recognized to be unsuitable to seed plants. In 1868, German botanist J. Hanstein suggested the histogen theory: this concept subdividing the SAM into dermatogen, periblem, and plerome was unable to generally apply to seed plants. In 1924, German botanist A. Schmidt proposed the tunica-corpus theory from the examination of angiosperm SAM in which two parts show different planes of cell division: this theory was proved to be not suitable to gymnosperm SAM, not have stable surface tunica layer. In 1938, American botanist A. Foster described zones in gymnosperm SAM based on the cytohistologic differentiation and thus called it a cytohistological zonation theory. With works by E. Gifford, in 1954, this zonation pattern was demonstrated to be also applicable to angiosperm SAM. As another theory, in 1952 French botanist R. Buvat proposed the m${\acute{e}}$rist${\grave{e}}$me d'attente (waiting meristem) theory: however, this concept was confuted because of its negation of function during vegetative growth phase to central initial cells. Rescent studies with Arabidopsis thaliana have found that formation and maintenance of the SAM are under the control of selected genes: SHOOTMERISTEMLESS (STM) gene forms the SAM, and WUSCHEL (WUS) and CLAVATA (CLV) genes function in maintaining the SAM; signaling between WUS and CLV genes act through a negative feedback loop.

• The Korean Journal of Petroleum Geology
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• v.10 no.1_2 s.11
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• pp.10-17
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• 2004

The Doowoo-ri tidal flat in the southwestern Korean coast is a typical open-coast tidal flat which has no barriers in the offshore such as barrier island and sand bars. The difference of induced wave energy with seasons is affected directly on the distribution of surface sediment and the formation of sedimentary structures because the sedimentation by wind wave is relatively much important element in this open-coast tidal flat. This open-coast tidal flat can be classified into tidal beach, intertidal flat and lower mudflat according to the pattern of geomorphology and sediment type. The intertidal flat can be again divided into 3 types: sand flat, mixed flat and mud flat based on the primary sedimentary structure and sand/mud ratio. Doowoori tidal flat shows a seasonal change in the surface sedimentary facies based on sediment composition and primary sedimentary structure. The change is closely related to the direction and magnitude of monsoon wind and also to storm frequency. In winter and spring, when northwesterly wind is most dominant and strong and also storms are common, sand-flat facies is largely distributed on the intertidal flat, whereas mud-flat facies is most dominant during summer when weak southeasterly wind is common. In the fall season, mixed-flat facies is dominant on the flat. The Doowoori intertidal flat is covered by mud sediment which is ca. 20 cm in thickness in summer season. In winter season, surface sediment is changed from mud to sand because the summer mud is mostly eroded by strong wave action. Can-core peels in the intertidal flat show that parallel laminated mud or sand/mud and climbing ripple cross-laminated sandy silt are dominant on the upper intertidal flat $(0-1.3 {\cal}km)$ during summer season. On the other hand, on lower intertidal flat $(1.7-2.3 {\cal}km)$, dominant sedimentary facies is homogeneous mud. In winter, it is changed into parallel laminated and ripple cross-laminated sand facies.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.357-368
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• 2003

Time-series CTDT (Conductivity/Temperature/Depth/Transmissivity) were obtained at one point near tidewater glacier of Marian Cove (King George Islands, Antarctica) to present water column properties and SPM (suspended particulate matter) dispersal pattern in relation with tide, current, meteorological data, and SPM concentration. Four layers were divided from the water column characteristics measured in the interval of an hour for about 2 days: 1) cold, fresh, and turbid surface mixed layer between 0-20 m in water depth, 2) warm, saline, and relatively clean Maxwell Bay inflow between 20-40 m in water depth, 3) turbid/cold tongue of subglacial discharges compared with the ambient waters between 40-70 m in water depth, and 4) cold, saline, and clean bottom water beneath 70 m in water depth. Surface plume, turbid freshwater at coastal/cliff area in late summer (early February), had the characteristic temperature and SPM concentration according to morphology, glacial condition, and composition of sediments. The restrict dispersion only over the input source of meltwater discharges was due to calm wether condition. Due to strong wind-induced surface turbulence, fresh and turbid surface plume, englacial upwelling cold water, glacier-contact meltwater, and Maxwell Bay inflow was mixing at ice-proximal zone and the consequent mixed layer deepened at the surface. Large amount of precipitation, the major controlling factor for increasing short-term glacial discharges, was accompanied by the apparent development of subglacial discharge that resulted in the rapid drop of salinity below the mid depth. Although amount of subglacial discharge and englacial upwelling may be large, however, their low SPM concentration would have small influence on bottom deposition of terrigenous sediments.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.1
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• pp.1-19
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• 2018

In order to compare significant wave height (SWH) data from multi-satellites (GFO, Jason-1, Envisat, Jason-2, Cryosat-2, SARAL) and SWH measurements from Ieodo Ocean Research Station (IORS), we constructed a 12 year matchup database between satellite and IORS measurements from December 2004 to May 2016. The satellite SWH showed a root mean square error (RMSE) of about 0.34 m and a positive bias of 0.17 m with respect to the IORS wave height. The satellite data and IORS wave height data did not show any specific seasonal variations or interannual variability, which confirmed the consistency of satellite data. The effect of the wind field on the difference of the SWH data between satellite and IORS was investigated. As a result, a similar result was observed in which a positive biases of about 0.17 m occurred on all satellites. In order to understand the effects of topography and the influence of the construction structures of IORS on the SWH differences, we investigated the directional dependency of differences of wave height, however, no statistically significant characteristics of the differences were revealed. As a result of analyzing the characteristics of the error as a function of the distance between the satellite and the IORS, the biases are almost constant about 0.14 m regardless of the distance. By contrast, the amplitude of the SWH differences, the maximum value minus the minimum value at a given distance range, was found to increase linearly as the distance was increased. On the other hand, as a result of the accuracy evaluation of the satellite SWH from the Donghae marine meteorological buoy of Korea Meteorological Administration, the satellite SWH presented a relatively small RMSE of about 0.27 m and no specific characteristics of bias such as the validation results at IORS. In this paper, we propose a conversion formula to correct the significant wave data of IORS with the satellite SWH data. In addition, this study emphasizes that the reliability of data should be prioritized to be extensively utilized and presents specific methods and strategies in order to upgrade the IORS as an international world-wide marine observation site.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.2
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• pp.91-108
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• 2018

An ecological study on subtidal macrobenthic fauna was conducted from 25 stations in the estuarine area of Wando-Doam Bay, southern coast of Korea during August 2013. A total of 186 species was collected with a mean density of $1,229ind./m^2$ and a mean biomass of $265.7g/m^2$. Polychaetes showed the richest benthic fauna comprising 43% of total fauna, whereas mollusks appeared as density- and biomass-dominant fauna accounted for 45% and 48% of the mean density and biomass, respectively. The number of species and mean faunal density were relatively higher at the stations surrounded by Sinjido, Joyakdo and Gogeumdo showing a gradual decrease toward inner bay stations. Species number and density were negatively correlated with bottom water temperature, but they were positively correlated with both the bottom salinity and DO. The most dominant species in terms of density was a semelid bivalve, Theora fragilis which showed a positive correlation with TOC content of surface sediment and its high density occurred around Gogeum-Sinji-Joyakdo area where dense aquaculture facilities exist. In the bay mouth area, an amphipod species, Eriopisella sechellensis showed its higher density at the stations with low organic content but fine grains. The combination of water temperature, salinity, pH of bottom water, water and sulfur content of the surface sediment could explain 71% of the spatial distribution of macrobenthic fauna from the Bio-Env analysis. From the cluster analysis, the study area consisted of 6 distinct station groups lineated from offshore area toward inner area. Ampharete arctica, Goniada maculata, Eriopisella sechellensis, Theora fragilis, Caprella sp. were identified as the main contributing faunas in classification by the SIMPER analysis. From the value of BPI, the benthic communities at the inner and central Wando-Doam Bay were assessed to be in a normal condition whereas those at the outer Wando harbor and Gogeum-Sinji-Joyakdo area were assessed in a poor or very poor condition due to the high concentration of particulate organic matter might be originated from the nearby dense aquaculture facilities. This study indicated that pristine inner bay has been influenced by the organic material supplied from the outer bay. Thus it is necessary to establish an ecological management plan to reduce organic enrichment of sediment from dense aquaculture facilities in the outer bay.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.131-137
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• 2012

Polyaniline (PANI) and polypyrrole (Ppy) hollow sphere structures with controlled shell thicknesses can be easily synthesized than those of using a layer-by-layer method for cathode active material of lithium-ion batteries. Polystyrene (PS) core was synthesized by emulsion polymerization using an anion surfactant. The shell thicknesses of PANI and Ppy were controlled by amounts of aniline and pyrrole monomers. PS was removed by an organic solution. This structure increased in contact with an electrolyte and a specific capacity in lithium-ion batteries. But polymers have disadvantages such as the difficult control of molecular weights and low densities. These disadvantages were completed by controlled shell thicknesses. The amount of aniline monomer increased from 1.2, 2.4, 3.6, 4.8 to 6.0 mL, and the shell thicknesses were 30.2, 38.0, 42.2, 48.2, and 52.4 nm, respectively. And the amount of pyrrole monomer was 0.6, 1.2, 2.4 and 3.6 mL, the shell thicknesses were 16.0, 22.0, 27.0 and 34.0 nm, respectively. In the cathode materials with controlled shell thicknesses, shell thicknesses of the PANI hollow spheres were 30.2, 42.2, and 52.4 nm, and discharge specific capacities of after 10 cycle were ~18, ~29, and ~62 mAh/g, respectively. The shell thicknesses of the Ppy hollow spheres were 16.0, 22.0, 27.0 and 34.0 nm, and discharge specific capacities of after 15 cycle were ~15, ~36, ~56, and ~77 mAh/g, respectively. Thus, shell thicknesses of PANI and Ppy increased, the specific capacities increased.

• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1140-1144
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• 2002

Molecular relaxation behaviors of crystalline glucose anhydrous, crystalline glucose monohydrate, and amorphous glucose with different particle sizes were observed by measuring spin-spin relaxation time constant $(T_2)$ at the temperature range of $-20\;to\;110^{\circ}C$ using temperature-controlled low field nuclear magnetic resonance spectroscopy. No change in $T_2$ values of crystalline glucose anhydrous was observed throughout the temperature range, whereas $T_2$ values of crystalline glucose monohydrate and amorphous glucose increased from around $45\;and\;65^{\circ}C$, respectively. These results indicate that molecular mobility of crystalline glucose anhydrous does not change even at temperature higher than $100^{\circ}C$ and that the stability of powdered glucose could be improved by increasing the particle size of materials.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.289-293
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• 2001

Objectives : The optimal treatment of craniopharyngioma is controversial. Despite recent advances in microsurgical management, complete surgical removal of craniopharyngioma remains very difficult. Radiation added to surgery is effective, but radiation therapy resulted in untoward side effect in young patient. Gamma knife radiosurgery offers the theoretical advantage of a reduced radiation dose to surrounding structures during the treatment of residual or recurrent craniopharyngioma compared with fractionated radiotheraphy. We described retrospective analysis of tumor size and clinical symptoms of patients after gamma knife radiosurgery in residual or recurrent craniopharyngioma were performed. Material and Methods : From September 1990 to January 2000, 18 patients of craniopharyngioma were treated by gamma knife radiosurgery. All patient had undergone surgery, but residual or recurrent tumor was found and all of them treated postoperative gamma knife radiosurgery. The mean age was 19(from 6 to 66) and male to female ratio was 10 to 8 and 8 patients were below 15 years old. In young age group(below age 15), the average volume of the tumor was $2904.8mm^3$ and mean maximal gamma knife dose was 34.9Gy. In old age group(older than 15), the average volume of the tumor was $2590.4mm^3$ and mean maximal gamma knife dose was 45.2Gy. The size of the tumor was average $2730.1mm^3$($88-12000mm^3$), mean average radiation dose was 40.7Gy and the mean prescription dose was 17.6 Gy(4-35Gy) delivered to a median prescription 50.7% isodose. Results : The follow up was from 1 year to 9 years(mean 59.1 months) after gamma knife radiosurgery. The tumor was controlled in 13(72.2%) patients. The tumor decreased in 9 patients and not changed in 4 patients. The tumor size increased in 4(22.2%) patients during follow up period. In two cases the tumor size increased because of its cystic portion was increased, but their solid portion of the tumor was not changed. In another two patients, the solid portion of the tumor was increased. So, one patient underwent reoperation and the other patient underwent operation and repeated gamma knife radiosurgery. The tumor recurred in one case(5.6%) that is a outside of irradiated site. The presenting symptoms were improved in 4 patients(improved visual acuity in 1, controlled increased intracranial presure sign in 3 patients). In one case, visual acuity decreased after gamma knife radiosurgery. The endocrine symptoms were not influenced by gamma knife radiosurgery. Conclusion : Craniopharyngioma can be treated successfully by gamma knife radiosurgery. Causes of the tumor regrowth are inadequate dose planning because of postoperatively poor margination of the tumor, close approximation of optic nerve and residual tumors outside the target lesion. Recurrence can develop 4 years after gamma knife radiosurgery. Volume is important, but the accurate targeting is more important to prevent tumor recurrence. If the tumor definition is not clear during planning gamma knife surgery, long-term image follow up is required.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.185-192
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• 1987

Anethole, eugenol, isoeugenol, safrole and isosafrole are ingredients of refined oils which are obtained from some plants and their chemical structures are very similar. They are mainly used as a flavoring agent, food additive, carminative. dental analgesics and for many drugs. But, there is no report about their effect on gastric secretion and gastric motility. To examine the effect of anethole, eugenol, isoeugenol, safrole and isosafrole on gastric secretion in rats and gastric motility in pigeons, this paper was investigated. The results were as follows ; 1. All of 5 essential oils showed significant inhibitory effect compared with control group on gastric secretion at the rate of 1.00 ml/100 g, 0.50 ml/100 g B. W. in the rat. 2. Eugenol, isoeugenol and isosafrole showed significant inhibitory effect on gastric secretion at the rate of 0.25 ml/100 g B. W. in the rat. 3. Isosafrole showed the most inhibitory effect on gastric secretion in 5 essential oils. 4. All of 5 essential oils, in a more or less degree. showed temporary inhibitory effect on gastric motility in the pigeon. 5. In conclusion, all of 5 essential oils showed inhibitory action on gastric secretion in the rat and gastric motility in the pigeon.