• Food Science and Preservation
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• v.14 no.2
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• pp.124-130
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• 2007

Lettuce (Lactuca Sativa L.) is the most popular salad vegetable crop The purpose of this study was to analyze the quality of lettuce, and residual pesticides in this vegetable, during growth after transplanting. The eatable weight was 40% of the total weight at the commencement of transplanting, but had doubted at harvest after transplanting. As lettuce grew after transplanting, the pH, the sugar level, and the moisture content increased slightly, and the color tended towards yellow rather than greenThe SPDA chlorophyll measurement was 16.84 at 42 day post-ransplantation, and increased to 26.44 at 67 day after transplanting. The contents of vitamin C were 2.5mg/100g wet weight at 60 d after transplantation, but decreased to 2.2mg/100g wet weight 67 day post-transplantation. Mineral (Ca, Fe, K, Mg, and Na) levels rose after transplantation, and attained their highest levels 60 day post-transplantation. The lettuce crop was analyzed for residues of each of 48 pesticides nt 54 after transplantation, and the only such chemical detected was chlorthalonil(0.03 0.25mg/kg wet weight).

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.133-141
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• 2019

High specific surface area zirconia with acid-basic property was synthesized by precipitation using reflux method or hydrothermal synthesis method using ammonium hydroxide solution as precipitant in the range of pH of Zr solution from 2 to 10. The prepared zirconia was characterized by the nitrogen adsorption, X-ray diffraction (XRD), isopropanol temperature programmed desorption (IPA-TPD), scanning electron microscopy and X-ray photoelectron spectroscopy, and the catalytic activity in the IPA decomposition reaction was correlated with the acid-basic properties. When using reflux method, high pH of Zr solution was required to obtain high fraction of tetragonal zirconia, and pure tetragonal zirconia was possible at pH 9 or higher. High pH was required to obtain high specific surface area zirconia, and the hydrous zirconia synthesized at pH 10 had high specific surface area zirconia of $260m^2g^{-1}$ even after calcination at $600^{\circ}C$. However, hydrothermal synthesis with high pressure under the same conditions resulted in very low specific surface area below $40m^2g^{-1}$ and monoclinic phase zirconia was synthesized. High pH of the solution was required to obtain high specific surface area tetragonal phase zirconia. In hydrothermal synthesis requiring high pressure, monoclinic zirconia was produced irrespective of the pH of the solution, and the specific surface area was relatively low. Zirconia with high specific surface area and tetragonal phase was predominantly acidic compared to basicity and only propylene, which was observed as selective dehydration reaction in IPA decomposition reaction, was produced.

• Korean Journal of Plant Taxonomy
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• v.48 no.4
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• pp.363-369
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• 2018

Since the establishment of the Korean Society of Plant Taxonomists (KSPT) on Dec. 13, 1968, the professional manpower training and research activities have been analyzed. The survey method was based on the homepage of the KSPT and the Korean J. Pl. Taxon, and on data provided by each university about professional manpower. Over the past 50 years, a total of 680 specialists in plant taxonomy have been trained, consisting of 537 master's degree holders (274 males, 263 females) from 30 universities and 143 PhDs (97 males, 46 females) from 26 universities, and the number has increased significantly since 1998. With regard to changes in the field of research over the last ten years, revision papers were the most common in the period of 1988-1997 (72%), but this rate has decreased to 51% over the last ten years, while the number of unrecorded papers has increased to 28%. In the 629 revision papers on taxa, 49% of the taxa belong to Asteraceae, Ranunculaceae, Cyperaceae, Liliaceae, Rosaceae, Fabaceae, Apiaceae, Lamiaceae, Orchidaceae, Oleaceae, Euphorbiaceae, Polygonaceae, and Amaryllidaceae. With regard to changes in research methods, the number of morphological papers increased from 6% to 51%, while pollen papers have decreased from a rate of 20% to only 2%. Chromosome studies account for 3-4%, chemotaxonomic studies 2%, and DNA studies remain low at 3-16%. The percentage of papers in English now stands at 43%, mainly due to the increased number of papers on unrecorded species.

• Journal of Korean Society of Disaster and Security
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• v.12 no.1
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• pp.57-66
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• 2019

One of the most serious problems with concrete small dams or barriers installed in small/median rivers is the deposit of sediments, especially, in Korea. An effective way to discharge such sediments to downstream is to construct a bypass pipe under the river bed. However, efficiency may become lowered if ripraps are entered into the bypass pipe. Therefore, in this study, we derived the threshold condition for the exclusion of ripraps from the bypass pipe using 3D numerical analysis. Upstream flow of the small dam was assumed to be stationary, and the energy concept was applied to the control volume containing the bypass pipe and its periphery. As a result, when the ratio of the water level difference between upstream and downstream to the diameter of the riprap was approximately equal to 1.2, the threshold condition for exclusion of the stones or riprap from the bypass pipe was affirmatively determined. If the characteristics of the adsorptive sediment adversely affecting the river environment in the future would be taken into account, results from this study are expected to put to practical use in the management of concrete small dam with bypass pipe system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.318-325
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• 2021

The objective of this study was to identify the effect of zebularine, a DNA methylation inhibitor, on the chromosomal association between homoeologous chromosomes in the wheat genetic background. Zebularine at a final concentration of 10 µM was used to treat the spikes of the double monosomic wheat addition line (DMA) with one Leymus mollis chromosome and one Leymus racemosus chromosome, both of which were in a homoeologous relationship. In late prophase, zebularine led to chromosome breakage in the Leymus homoeologous chromosomes. Chromosome breakage caused an increase in the frequency of chromosomal associations between the Leymus homoeologous chromosomes. Ordinary DMA showed 65 cells (35.3%) with chromosomal associations and 119 cells (64.7%) with no association, whereas treated DMA showed 102 cells (60.0%) with chromosomal associations and 67 cells (39.4%) with no association. In diakinesis, the Leymus bivalent showed a chromosomal association in the whole euchromatic region. In metaphase, the Leymus bivalent showed association in the whole chromosomal region, unlike other Leymus bivalents with partial chromosomal association. Chromosomal association by chromosome breakage occurred not only between Leymus chromosomes but also between Leymus and wheat chromosomes. The frequency of other chromosomal association (such as fusion and insert) was increased. Chromosome breakage by zebularine treatment is a useful method at the chromosome level as the spores with others are hereditary stable, although the homologous index (h) was not significantly different between ordinary DMA and treated DMA. It is necessary to study how to control zebularine treatment with a more stable concentration for chromosome breakage during meiosis.

• Applied Chemistry for Engineering
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• v.33 no.2
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• pp.151-158
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• 2022

In this paper, parameter characteristics such as pH effect, isotherm, kinetic and thermodynamic parameters and competitive adsorption of dyes including malachite green (MG), direct red 81 (DR 81) and thioflavin S (TS), which have different functional groups, being adsorbed onto activated carbon were investigated. Langmuir, Freundlich and Temkin isotherm models were employed to find the adsorption mechanism. Effectiveness of adsorption treatment of three dyes by activated carbon were confirmed by the Langmuir dimensionless separation factor. The mechanism was found to be a physical adsorption which can be verified through the adsorption heat calculated by Temkin equation. The adsorption kinetics followed the pseudo second order and the rate limiting step was intra-particle diffusion. The positive enthalpy and entropy changes showed an endothermic reaction and increased disorder via adsorption at the S-L interface, respectively. For each dye molecule, negative Gibbs free energy increased with the temperature, which means that the process is spontaneous. In the binary component system, it was found that the same functional groups of the dye could interfere with the mutual adsorption, and different functional groups did not significantly affect the adsorption. In the ternary component system, the adsorption for MG lowered a bit, likely to be disturbed by the other dyes meanwhile DR 81 and TS were to be positively affected by the presence of MG, thus resulting in much higher adsorption.

• Ecology and Resilient Infrastructure
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• v.10 no.1
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• pp.11-19
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• 2023

Alien species are known to threaten regional biodiversity globally, which has increased global interest regarding introduction of alien species. The Ministry of Environment of Korea designated species that have not yet been introduced into the country with potential threat as alert alien species to prevent damage to the ecosystem. In this study, potential habitats of Esox lucius and Maccullochella peelii, which are predatory and designated as alert alien fish, were predicted on a national basis. Habitat suitability was evaluated using EHSM (Ecological Habitat Suitability Model), and water temperature data were input to calculate Physiological Habitat Suitability (PHS). The prediction results have shown that PHS of the two fishes were mainly controlled by heat or cold stress, which resulted in biased habitat distribution. E. lucius was predicted to prefer the basins at high latitudes (Han and Geum River), while M. peelii preferred metropolitan areas. Through these differences, it was expected that the invasion pattern of each alien fish can be different due to thermal preference. Further studies are required to enhance the model's predictive power, and future predictions under climate change scenarios are required to aid establishing sustainable management plans.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.2
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• pp.23-38
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• 2022

This study investigates the characteristics and physical habitat requirements for each Bufo gargarizans life history through a literature survey. After deriving variables for each component of Bufo gargarizans, in order to reduce regional deviations from eight previously studied literature research areas for deriving the criteria for variables, a total of 12 natural habitats of Bufo gargarizanss are selected as spatial ranges by selecting four additional sites such as Umyeonsan Ecological Park in Seoul, Wonheungibangjuk in Cheongju in the central region, Changnyeong Isan Reservoir in the southern region, and Mangwonji in Daegu. This study presents Bufo gargarizans SI, a species endemic to Korea, whose population is rapidly declining due to large-scale housing site development and road development, and develops a Bufo gargarizans HSI model accordingly to improve the function of the damaged Bufo gargarizans habitat and to present an objective basis for site selection of alternative habitat. At the same time, it provides basic data for adaptive management and follow-up monitoring. The three basic habitat requirements of amphibians, the physical habitat requirements of Bufo gargarizans, synthesized with shelter, food, and water, and the characteristics of each life history, are classified into five components by adding space and threats through literature research and expert advice. Variables are proposed by synthesizing and comparing the general characteristics of amphibians, among the previously studied single species of amphibians, the components of HSI of goldfrogs and Bufo gargarizans, and the ecological and physical environmental characteristics of Bufo gargarizans. Afterwards, through consultation with an amphibian expert, a total of 10 variables are finally presented by adjacent forest area(ha), the distance between spawning area and the nearest forest land(m), the soil, the distance from the wetland(m), the forest layered structure, the low grassland space, the permanent wetland area(ha), shoreline slope(%), PH, presence of predators, distance from road(m), presence or absence of obstacles. n order to derive the final criteria for each of the 10 variables, the criteria(alternative) for each variable are presented through geographic information analysis of the site survey area and field surveys of the previously studied literature research area. After a focus group interview(FGI) of 30 people related to the Bufo gargarizans colony in Cheongju, a questionnaire and in-depth interviews with three amphibians experts are conducted to verify and supplement the criteria for each final variable. Based on the finally developed Bufo gargarizans HSI, the Bufo gargarizans habitat model is presented through the SI graph model and the drawing centering on the Bufo gargarizans spawning area

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.266-274
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• 2022

Background Many authors have researched ways to optimize fat grafting by looking for a technique that offers safe and long-term fat survival rate. To date, there is no standardized protocol. We designed a "hydraulic system technique" optimizing the relationship among the quantity of injected fat, operative time, and material cost to establish fat volume cutoffs for a single procedure. Methods Thirty-six patients underwent fat grafting surgery and were organized into three groups according to material used: standard, "1-track," and "2-tracks" systems. The amount of harvested and grafted fat as well as material used for each procedure was collected. Operating times were recorded and statistical analysis was performed to establish the relationship with the amount of treated fat. Results In 15 cases the standard system was used (mean treated fat 72 [30-100] mL, mean cost 4.23 ± 0.27 euros), in 11 cases the "1-track" system (mean treated fat 183.3 [120-280] mL, mean cost 7.63 ± 0.6 euros), and in 10 cases the "2-tracks" one (mean treated fat 311[220-550] mL, mean cost 12.47 ± 1 euros). The mean time difference between the standard system and the "1-track" system is statistically significant starting from three fat syringes (90 mL) in 17.66 versus 6.87 minutes. The difference between the "1-track" system and "2-tracks" system becomes statistically significant from 240 mL of fat in 15 minutes ("1-track") versus 9.3 minutes for the "2-tracks" system. Conclusion Data analysis would indicate the use of the standard system, "1-track," and "2-tracks" to treat an amount of fat < 90 mL of fat, 90 ÷ 240 mL of fat, and ≥ 240 mL of fat, respectively.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1615-1615
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• 2001

During the past ten years, Near Infrared Spectroscopy has been successfully applied to the analysis of a great variety of agriculture products. Previous works (Morra et al., 1991; Salgo et al., 1998) have shown the potential of this technology for soil analysis, estimating different parameters just with one single scan. The main advantages of NIR applications in soils are the speed of response, allowing the increase of the number of samples analysed to define a particular soil, and the instantaneous elaboration of recommendations for fertilization and soil amendment. Another advantage is to avoid the use of chemical reagents at all, being an environmentally safe technique. In this paper, we have studied a set of 129 soil samples selected from representative glasshouse soils from Southern Spain. The samples were dried, milled, and sieved to pass a 2 mm sieve and then analysed for organic carbon, total nitrogen, inorganic nitrogen (nitrate ammonium), hygroscopic humidity, pH and electrical conductivity in the 1:1 extract. NIR spectra of all samples were obtained in reflectance mode using a Foss NIR Systems 6500 spectrophotometer equipped with a spinning module. Calibration equations were developed for seven analytical parameters (ph, Total nitrogen, organic nitrogen, organic carbon, C/N ratio and Electric Conductivity). Preliminary results show good correlation coefficients and standard errors of cross validation in equations obtained for Organic Carbon, Organic Nitrogen, Total Nitrogen and C/N ratio. Calibrations for nitrates and nitrites, ammonia and electric conductivity were not acceptable. Calibration obtained for pH had an acceptable SECV, but the determination coefficient was found very poor probably due to the reduced range in reference values. Since the estimation of Organic Carbon and C/N ratio are acceptable NIIRS could be used as a fast method to assess the necessity of organic amendments in soils from Mediterranean regions where the low level of organic matter in soils constitutes an important agronomic problem. Furthermore, the possibility of a single and fast estimation of Total Nitrogen (tedious determination by modifications of the Kjeldahl procedure) could provide and interesting data to use in the estimation of nitrogen fertilizer rates by means of nitrogen balances.