• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.253-275
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• 1994

Many flowering plants possess genetically controlled self -incompatibility (SI) system that prevents inbreeding and promotes outcrosses. SI is usually controlled by a single, multiallelic S-locus. In gametophytically controlled system, SI results when the S-allele of the pollen is matched by one of the two S-alleles in the style, while in the sporophytic system self-incompatible reaction occurs by the interaction between the pistil genotype and genotype of, not the pollen, but the pollen parent In the former system the self-incompatible phenotype of pollen is determined by the haploid genome of the pollen itself but in the latter the pollen phenotype is governed by the genotype of the pollen parent along with the occurrence of either to-dominant or dominant/recessive allelic interactions. In the sporophytic type the inhibition reaction occurs within minutes following pollen-stigma contact, the incompatible pollen grains usually failing to germinate, whereas in gametophytic system pollen tube inhibition takes place during growth in the transmitting tissue of the style. Recognition and rejection of self pollen are the result of interaction between the S-locus protein in the pistil and the pollen protein. In the gametophytic SI the S-associated glycoprotein which is similar to the fungal ribonuclease in structure and function are localized at the intercellular matrix in the transmitting tissue of the style, with the highest concentration in the collar of the stigma, while in the sporophytic SI deposit of abundant S-locus specific glycoprotein (SLSG).is detected in the cell wall of stigmatic papillae of the open flowers. In the gametophytic system S-gene is expressed mostly at the stigmatic collar the upper third of the style length and in the pollen after meiosis. On the other hand, in the sporophytic SI S-glycoprotein gene is expressed in the papillar cells of the stigma as well as in e sporophytic tape is cells of anther wall. Recognition and rejection of self pollen in the gametophytic type is the reaction between the ribonuclease in the transmitting tissue of the style and the protein in the cytoplasm of pollen tube, whereas in the sporophytic system the inhibition of selfed pollen is caused by the interaction between the Sycoprotein in the wall of stigmatic papillar cell and the tapetum-origin protein deposited on the outer wall of the pollen grain. The claim that the S-allele-associated proteins are involved in recognition and rejection of self pollen has been made merely based on indirect evidence. Recently it has been verified that inhibition of synthesis of S$_3$ protein in Petunia inflata plants of S$_2$S$_3$ genotype by the antisense S$_3$ gene resulted in failure of the transgenic plant to reject S$_3$ pollen and that expression of the transgenic encoding S$_3$ protein in the S$_1$S$_2$ genotype confers on the transgenic plant the ability to reject S$_3$ pollen. These finding Provide direct evidence that S-proteins control the s elf-incompatibility behavior of the pistil.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.454-460
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• 2016

In this study, we investigated the possibility of Droplet digital PCR (ddPCR) for detection of foodborne pathogens. ddPCR combines partitioning of PCR reactions into several thousands or millions of individual droplets in a water-oil emulsion, and counting of positive PCR reaction using flow cytometry. Four species of foodborne pathogens, Bacillus cereus, Staphylococcus aureus, Salmonella Typhimurium and Escherichia coli O157:H7, were used to quantify the target sequence with each of the designed primers and double stranded DNA-binding Evagreen dye. All tested foodborne pathogens showed a detection limit ranging from $100fg/{\mu}L$ to $10ng/{\mu}L$. It was concluded that ddPCR could be used to detect very low concentrations of foodborne pathogens from complex food matrices. For multi-detection of target pathogens, we also tested the samples using multiplex ddPCR and obtained successful results.

• YAKHAK HOEJI
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• v.42 no.1
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• pp.25-30
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• 1998

This study was designed to compare the absorption fraction and extent of ketoprofen gels and a matrix typed ketoprofen plaster patch. 3g (90mg as ketoprofen) of the two gels whi ch has oleohydrogel or hydrogel as a base, respectively, and 3 pieces of plaster patches (90mg as ketoprofen) were, applied in the area of 210$cm^2$ on forearm in 12 volunteers by cross over design. Blood samples were collected serially up to 24 hours and the plasma concentrations of ketoprofen were analyzed by HPLC using flurbiprofen as an internal standard. The detection limit of the assay was 1ng/ml of ketoprofen in plasma. The pharmacokinetic parameters (e.g. $AUC_{24hr}$, $AUMC_{24hr}$, MRT, Fraction Absorbed) were calculated from the plasma concentrations time data of each volunteer. The oleo-hydrogel showed significantly higher absorption fraction and extent of ketoprofen than the current hydrogel. The mean plasma concentrations of the oleo-hydrogel were increased to 98.46${\pm}$23.15ng/ml by 6 hour after application, and increased futher to 100.61${\pm}$18.65ng/ml at 24 hour. On the other hand, those of the hydrogel were increased 17.61${\pm}$18.65ng/ml at 5 hour to 34.68${\pm}$9.65ng/ml at 24 hour gradually. Therefore the plasma concentrations of oleo-hydrogel at each measured time were 3~7 times greater than those of the hydrogel with statistical significance. The $AUC_{24hr}$ (1797.26${\pm}$52.09ng.h/ml) of the oleo-hydrogel was 3.5 times greater (P<0.05) than that (516.17${\pm}$104.52ng.h/ml) of the hydrogel. The plaster patches showed higher bioavailability ($AUC_{24hr}$ 2877.37${\pm}$578.27ng.h/ml) than the olea-hydrogel ($AUC_{24hr}$ 1797.26${\pm}$52.09ng.h/ml) without statistical significance. But the absorption fraction of the oleo-hydrogel was rather higher than that of the plaster patches during the first 6 hours after administration. These results suggest that newly developed ketoprofen gel which is used oleo-hydrogel as a base would show excellent skin permeation on topical application for the corresponding clinical indications and could be absorbed as well as plaster patches.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.2
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• pp.89-101
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• 2019

In recent times, the number of men with late-onset hypogonadism has increased, and interest on this topic has also increased. This study was conducted to investigate effects of the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus on improve late-onset hypogonadism. The experimental subjects consisted of three groups: a control group consisting of 8-week-old male ICR mice that had undergone no treatment, an aging-elicited group (AE group) consisting of 50-week-old ICR male mice that had undergone no treatment, and a Mixed herbal extract treatment group (MT group) consisting of 50-week-old ICR male mice that had undergone the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus treatment (0.1 g/kg/day) for 6 months. After the experiment, the mice from all the experimental groups were dissected, and they were analyzed through histochemical and immunohistochemical methods. The mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus reduces aging-induced cell damage and oxidative stress and increases the secretion of serotonin and B-endorphin in aged mice, and promotes spermatogenesis in seminiferous tubules and reduces apoptosis and oxidative stress, and increases androgen receptor, $17{\beta}-HSD$ and GnRH, increases the ratio of smooth muscle to collagen fibers in the corpus cavernosum, increases eNOS, decreases PDE-5 and oxidative stress in aged mice, so it improves depression, reproductive, sexual problems caused by Late-onset hypogonadism. the mixture extract of Fructus amomi Amari, Eucommiae cortex, Bombyx batryticatus inhibits the induction of osteoporosis by increasing decreased bone matrix distribution due to aging, increasing the activities of OPC and OPN, which are produced in osteoblasts, and decreasing RANKL, MMP-3 activity, increasing OPG activity. It also reduces muscle damage, oxidative stress, inflammation and apoptosis of muscle tissue, and increases Myo-D in the sartorius muscle of aged mice for improving muscle atrophy caused by by Late-onset hypogonadism.

• Geophysics and Geophysical Exploration
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• v.24 no.2
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• pp.35-44
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• 2021

As the execution speed of Python is slower than those of other programming languages (e.g., C, C++, and FORTRAN), Python is not considered to be efficient for writing numerical geodynamic code that requires numerous iterations. Recently, many computational techniques, such as the Just-In-Time (JIT) compiler, have been developed to enhance the calculation speed of Python. Here, we developed two-dimensional (2D) numerical geodynamic code that was optimized for the JIT compiler, based on Python. Our code simulates mantle convection by combining the Particle-In-Cell (PIC) scheme and the finite element method (FEM), which are both commonly used in geodynamic modeling. We benchmarked well-known mantle convection problems to evaluate the reliability of our code, which confirmed that the root mean square velocity and Nusselt number obtained from our numerical modeling were consistent with those of the mantle convection problems. The matrix assembly and PIC processes in our code, when run with the JIT compiler, successfully achieved a speed-up 30× and 258× faster than without the JIT compiler, respectively. Our Python-based FEM-PIC code shows the high potential of Python for geodynamic modeling cases that require complex computations.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.1-11
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• 2021

In this review, recent foodborne outbreaks caused by viruses in the Republic of Korea (2010-2019) were analyzed. The human norovirus was found to be the major foodborne virus causing an average of 94.9% of the viral outbreaks. Reverse-transcription polymerase chain reaction (PCR) with electrophoresis has been widely used to detect viruses, but several rapid detection methods, including real-time PCR, multiplex PCR, and quantum dot assay, have also been suggested. For norovirus inactivation studies, surrogates such as murine norovirus and feline calicivirus have been widely used to identify the reduction rate owing to the limitations in laboratory cultivation. Conversely, direct cell infection studies have been conducted for other foodborne viruses such as adenovirus, astrovirus, rotavirus, and hepatitis A or E virus. Moreover, virucidal mechanisms using various physical and chemical treatments have been revealed. These recent studies suggest that rapid in situ detection and effective control are valuable for ensuring food safety against viral infections.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.174-174
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• 2000

A strong antiferromagnetic coupling in Fe/Si multilayered films (MLF) had been recently discovered and much consideration has been given to whether the coupling in the Fe/Si MLF system has the same origin as the metal/metal MLF. Nevertheless, the nature of the interfacial ron silicide is still controversial. On one hand, a metal/ semiconductor structure was suggested with a narrow band-gap semiconducting $\varepsilon$-FeSi spacer that mediates the coupling. However, some features show that the nature of coupling can be well understood in terms of the conventional metal/metal multilayered system. It is well known that both magneto-optical (MO) and optical properties of a metal depend strongly on their electronic structure that is also correlated with the atomic and chemical ordering. In this study, the nature of the interfacial regions is the Fe/Si multilayers has been investigated by the experimental and computer-simulated MO and optical spectroscopies. The Fe/Si MLF were prepared by rf-sputtering onto glass substrates at room temperature with the number of repetition N=50. The thickness of Fe sublayer was fixed at 3.0nm while the Si sublayer thickness was varied from 1.0 to 2.0 nm. The topmost layer of all the Fe/Si MLF is Fe. In order to carry out the computer simulations, the information on the MO and optical parameters of the materials that may constitute a real multilayered structure should be known in advance. For this purpose, we also prepared Fe, Si, FeSi2 and FeSi samples. The structural characterization of Fe/Si MLF was performed by low- and high -angle x-ray diffraction with a Cu-K$\alpha$ radiation and by transmission electron microscopy. A bulk $\varepsilon$-FeSi was also investigated. The MO and optical properties were measured at room temperature in the 1.0-4.7 eV energy range. The theoretical simulations of MO and optical properties for the Fe/Si MLF were performed by solving exactly a multireflection problem using the scattering matrix approach assuming various stoichiometries of a nonmagnetic spacer separating the antiferromagnetically coupled Fe layers. The simulated spectra of a model structure of FeSi2 or $\varepsilon$-FeSi as the spacer turned out to fail in explaining the experimental spectra of the Fe/Si MLF in both intensity and shape. Thus, the decisive disagreement between experimental and simulated MO and optical properties ruled out the hypothesis of FeSi2 and $\varepsilon$-FeSi as the nonmagnetic spacer. By supposing the spontaneous formation of a metallic ζ-FeSi, a reasonable agreement between experimental and simulated MO and optical spectra was obtained.

• Nuclear Engineering and Technology
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• v.54 no.11
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• pp.4348-4358
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• 2022

The thermal-hydraulics phenomena in a containment during an accident will necessarily include radiative heat transfer (i) within the gas mixture due to the high radiative absorption and emission of steam and (ii) between the gas mixture and the surrounding structures. The analysis of some previous PANDA experiments (PSI, Switzerland) demonstrated the importance of the proper modelling of radiation for the benefit of numerical simulations. These results together with dedicated scoping calculations conducted for the present experiments indicated that the radiative heat transfer is considerable, even for a very low amount of steam (≈2%). The H2P2 series conducted in the large-scale PANDA facility at the Paul-Scherrer-Institut (PSI) in the framework of the OECD/NEA HYMERES-2 project is intended to enhance the understanding of thermal radiation phenomena and to provide a benchmark for corresponding numerical simulations. Thus, the test matrix was tailored around the two opposite extremes: either gas compositions with small steam content such that radiative heat transfer phenomena can be neglected. Or gas mixtures containing larger amounts of steam, so that radiative heat transfer is expected to play a dominant role. The H2P2 series consists of 5 experiments designed to isolate the radiation phenomena from convective and diffusive effects as much as possible. One vessel with a diameter of 4 m and a height of 8 m was preconditioned with different mixtures of air / steam at room and elevated temperatures. This was followed by the build-up of a stable helium stratification at constant pressure in the upper part of the vessel. After that, helium was injected from the top into the vessel which leads to an increase of the vessel pressure and a corresponding elevation-dependent and transient rise of the gas temperature. It is shown that even the addition of small amounts of steam in the initial gas atmosphere considerably impacts the radiative heat transport throughout all phases of the experiments and markedly influences i) the monitored gas peak temperature, ii) the temperature history during the compression and iii) the following relaxation phase after the compression was stopped. These PANDA experiments are the first of its kind conducted in a large scale thermal-hydraulic facility.

• Journal of the Korean Geotechnical Society
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• v.23 no.4
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• pp.91-100
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• 2007

In most design codes, soils are classified as either sand or clay, and appropriate design equations are used to represent their behavior. For example, the behavior of sandy soils is expressed in terms of the relative density, whereas consistency limits are often used for clays. However, sand-clay mixtures, which are typically referred to as intermediate soils, cannot be easily categorized as either sand or clay and therefore a unified interpretation of how the soil will behave at the transition point, i.e., from sandy behavior when fines are low to clay behavior for high fines content, is necessary. In this study, active natural clays are mixed with sand, and the fines content varied in order to produce different structures, ranging from one state where only sand particles form the soil structure to another where the matrix of fines make-up the structure. While paying attention to the granular void ratio in order to clarify the shear properties of sand-clay mixtures with increasing fines content monotonic, shear tests were performed on isotropically, and anisotropically consolidated specimens. From the test results, it was observed that the monotonic shear strength of sand-clay mixtures is dependent on the granular void ratio.

• Communications of Mathematical Education
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• v.37 no.1
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• pp.65-84
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• 2023

The method of Lagrange multipliers, one of the most fundamental algorithms for solving equality constrained optimization problems, has been widely used in basic mathematics for artificial intelligence (AI), linear algebra, optimization theory, and control theory. This method is an important tool that connects calculus and linear algebra. It is actively used in artificial intelligence algorithms including principal component analysis (PCA). Therefore, it is desired that instructors motivate students who first encounter this method in college calculus. In this paper, we provide an integrated perspective for instructors to teach the method of Lagrange multipliers effectively. First, we provide visualization materials and Python-based code, helping to understand the principle of this method. Second, we give a full explanation on the relation between Lagrange multiplier and eigenvalues of a matrix. Third, we give the proof of the first-order optimality condition, which is a fundamental of the method of Lagrange multipliers, and briefly introduce the generalized version of it in optimization. Finally, we give an example of PCA analysis on a real data. These materials can be utilized in class for teaching of the method of Lagrange multipliers.