• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.380-386
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• 2000

Electron beam (EB) was applied to study the sterilizing techniques for powdered red pepper and ginger by determining their quality over gamma radiation (GR) from the microbiological and organoleptic points of view. The samples showed high microbial loads, such as $10^5{\sim}10^6\;CFU/g$ in total aerobic bacteria, negligible levels in yeasts & molds and $10^2\;CFU/g$ in coliforms. EB irradiation at 5 kGy resulted in the reduction of microbial loads by 2 to 3 log cycles, thereby decreasing the levels of total bacteria to $10^2{\sim}10^3\;CFU/g$ and resulting in negative in coliforms. Decimal reduction doses $(D_{10})$ value on the initial bacterial loads in red pepper were $1.50{\sim}1.54\;kGy$ in EB and $1.68{\sim}1.80\;kGy$ in GR, while powdered ginger showed $1.30{\sim}2.27\;kGy$ in EB and $1.45{\sim}2.77\;kGy$ in GR, respectively. EB and GR showed a similar effect on microbial decontamination for both samples. Microbial populations in stored samples for 4 months at room temperature were not remarkably different from the initial loads in all samples. Irradiation caused little changes in Hunter's color parameters, but that were changable during storage. Sensory evaluations on color and odor of powdered samples indicated that no significant differences were observed among the all samples compared. These results revealed that EB irradiation at optimal dose levels for microbial control was not detrimental to the sensory quality of powdered red pepper and ginger.

• Journal of Korean Neurosurgical Society
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• v.29 no.3
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• pp.336-344
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• 2000

Objective : The treatment for prolactin secreting pituitary adenoma(prolactinoma) include pharmacology, surgery, radiation therapy or radiosurgery. The recent development of radiological imaging and microsurgery has made transsphenoidal microsurgery the treatment of choice for most prolactin secreting pituitary adenoma. Despite its low morbidity and mortality, relatively high recurrence and failure rate have been reported. Recent advances in neuroimaging provide a precise targeting in radiosurgery for treatment of prolactin secreting pituitary adenoma. In this regard, Gamma knife radiosurgery has been proposed as an alternative primary treatment modality or adjuvant therapy. Patients and Methods : Twenty three patients with prolactin secreting pituitary adenoma have been treated with Gamma knife radiosurgery in our institute from March 1992 to September 1998. We analyzed clinical, radiological and endocrinological changes in 21 patients who were followed up for an average of 35.7 months. Results : The mean age was 34.9 years and 16 patients were treated with Gamma knife radiosurgery as primary treatment and 5 patients underwent Gamma knife radiosurgery for residual tumors after microsurgery. The margin of the tumor was incorporated within the 40 to 80% and the mean marginal dose was 24.5 Gy. Clinical improvement in the last follow-up were present in 17 cases(81.0%) and 3 of 5 infertility patients became pregnant after Gamma knife radiosurgery. Tumor control rate after Gamma knife radiosurgery was 100%. Endocrinological normalization in the last follow-up were obtained in 12 cases(57.1%). In three cases, hormonal normalizations were present in early period(3-32 months) but serum hormone levels were elevated subsequently. Conclusion : We conclude that the Gamma knife radiosurgery for prolactin secreting pituitary adenoma seems to be safe and effective as adjuvant therapy after microsurgery and primary treatment modality in selective patients.

• Current Research on Agriculture and Life Sciences
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• v.30 no.2
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• pp.82-89
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• 2012

Commercial powdered soups, such as potato soup(PS), corn soup(CS), and chicken-herb soup(CHS), were gamma-irradiated at 0, 1, 5 and 10 kGy and subjected to physicochemical evaluation and identification trials by analyzing photostimulated luminescence(PSL), electron spin resonance(ESR), and thermoluminescence(TL). The changes in moisture content and pH of soup samples were negligible upon irradiation. The Hunter's color determinations showed that lightness (L value) decreased and yellowness (b value) increased as the irradiation dose increased in PS sample. The viscosity of irradiated samples was reduced in the order of PS, CS and CHS. The analyses of PSL, ESR and TL were applicable to the identification of irradiated powdered-soups at more than 1 kGy by detecting PSL photon counts/60 sec(over 5000), radiation-induced multicomponents-ESR signal, and typical TL glow curve at $150-250^{\circ}C$.

• FLOWER RESEARCH JOURNAL
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• v.16 no.3
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• pp.211-217
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• 2008

To build up data for mutation breeding of lily, sensitivity to irradiation of bulb, seed and pollen was investigated. The bulbs of seven cultivars including 'New Wave' were very sensitive to gamma rays. Non-irradiated bulbs produced plants with bloom as normal. However, irradiated bulbs showed retarded growth and did not flower. Bulbs of 'New Wave' and 'Tiny Dino' irradiated with 125Gy gamma rays survived, but their growth rate dropped considerably. Part or whole leaves of the other cultivars except 'New Wave' and 'Tiny Dino' withered. Moisture content of individual scale was 72~78% depending on cultivar. Bulblet formation from untreated scales was 100%. Among all irradiated scales only 'Siberia' scales showed 8.5% bulblet formation when irradiated with 50Gy gamma rays. Pollen germination as affected by gamma ray irradiation had no consistent tendency. When dosage of $F_1$ 'Augusta' seeds reached 300Gy, their survival ratio was drastically decreased. Bulblet formation in vitro was observed only in non-irradiated seeds. Lethal dose ($LD_{50}$) of seed was less than 100Gy. Height and width of $F_1$ 'Augusta' bulblets in vitro irradiated with gamma rays decreased as dosage increased regardless of the culture method. The percentage shoot formation was 100% in non-irradiated bulblets and 15~60% in irradiated ones.

• Korean Journal of Remote Sensing
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• v.9 no.2
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• pp.51-69
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• 1993

Precipitable Water(PW) are retrieved over the tropical and subtropical Pacific Ocean from TOVS infrared and microwave channel brightness temperature and OLR observations by means of stepwise linear regression. The retrieved TOVS PW fields generated by PW$_{sfc}$(71.1 % of the variance and 0.62 g cm$^{-2}$ standard error over the surface) and PW$_{700500}$(71.7 % and 0.17 g cm$^{-2}$ over the 700 - 500 hPa layer) revealed more evolving synoptic signals over the tropical and subtropical Pacific Ocean. The PW$_{sfc}$ dose not show significantly the TP feature because of the representation of the lower PW for high-level clouds not associated with deep convection. There exists some elusion to trace the TP on the PW$_{sfc}$ field if any supplementary information does not provide. But ECMWF analysis has a general tendency of drying the subtropics and moistening the ITCZ (InterTropical Convergence Zone) and SPCZ(South Pacific Convergence Zone). However, although ECMWF analysis is fairly successful in capturing mean patterms, it is unsuccessful in following active synoptic signal like a tropical plume. Similarly, SMMR-PW does not represent the TP well which consists of the highand middle-level clouds, but PW$_{sfc}$ shows underestimated moistness of TP and does not depict significant signal of TP. In the PW field derived from microwave observations, the TP can not be recognized well. Furthermore, the signature of PW$_{sfc}$ was different from OLR for the TP, which implies the presence of high- and middle-layer thin clouds, but in a closer agreement for deep and active convection areas which contain thick middle- and lower-layer clouds; though OLR represented the cloudiness in the tropics well. In synoptically active regions, it differed from OLR analysis, primarily bacause of actual differences in water vapor and cloud features. The signature of PW$_{sfc}$ was different from OLR for the TP.

• Journal of Life Science
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• v.29 no.11
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• pp.1200-1207
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• 2019

Ultraviolet radiation exposure is a major cause of extrinsic skin aging, which leads to skin hyperpigmentation. Loganin, a major iridoid glycoside obtained from Corni fructus, has anti-inflammatory, anti-diabetic, and neuroprotective effects. In this study, we investigated the mechanisms underlying the anti-melanogenic effects of loganin in B16F10 melanocytes treated with ${\alpha}$-melanocyte stimulating hormone (${\alpha}-MSH$) and 3-isobutyl-1-methylxanthine (IBMX). Anti-melanogenic activity was measured by treating cells with loganin at concentrations between 1 and $20{\mu}m$. Cell viability assays confirmed that doses of loganin up to $20{\mu}m$ were not cytotoxic. Loganin significantly and dose-dependently decreased intracellular melanin production. We also investigated potential molecular signaling pathways for the anti-melanogenesis effects of loganin. Western blotting showed that treatment with ${\alpha}-MSH$ and IBMX increased the phosphorylation of cAMP response element-binding protein (CREB) and the gene expressions of microphthalmia-associated transcription factor (MITF) and tyrosinase. Addition of loganin suppressed these increases, while promoting the phosphorylation of extracellular signal regulated kinase (ERK) and the anti-melanogenesis response. Our data therefore indicated that loganin could attenuate the increased melanin synthesis induced by ${\alpha}-MSH$ and IBMX treatment of B16F10 melanocytes. This attenuation appears to occur by downregulation of CREB phosphorylation and MITF and tyrosinase gene expression and upregulation of ERK phosphorylation. These finding suggests that loganin could be a valuable candidate for treatment of skin diseases related to hyperpigmentation.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.34 no.3
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• pp.217-223
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• 2008

Elastin is an important component of elastic fibers in the skin. Recently, many studies have reported that elastin is also involved In inhibiting or repairing wrinkle formation, although collagen is a major factor in the skin wrinkle formation. Elastase is a metalloproteinase which acts on degradation of elastin. It is known that elastase activity is increased by ultraviolet (UV) B radiation. Thus, Increased elastase activity could be the major reason for skin elasticity reduction and winkle formation. Tannic acid is a polyphenol found in various fruits and nuts. This molecule has a potent ability to eliminate reactive oxygen species and reactive nitrogen species. In the present study, we investigated whether tannic acid has effects on elastase activity and tropoelastin synthesis. Our results showed that tannic acid reduced elastase activity significantly in a dose-dependent manner. However, the expression of tropoelastin protein and mRNA was not significantly affected by tannic acid. From these results, we suggest that tannic acid may contribute to block tortuosity of elastic fibers by inhibiting elastase. Thus, tannic acid might be developed for a possible agent to Inhibit skin aging.

• Journal of Mushroom
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• v.19 no.3
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• pp.140-149
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• 2021

Mushroom-derived polysaccharides, which are the primary bioactive constituents, are beneficial for human health. Polysaccharides have immuno-modulation, antitumor, and antioxidant properties. Additionally, they have antiviral properties and protect against chronic radiation stress. In this study, high yield water-soluble polysaccharides were obtained from Pleurotus djamor var. roseus basidiocarps. The crude polysaccharide (CP) was extracted sequentially by hot water and ethanol precipitation. The yield of the brown CPs was 5.6% dw. Diethylaminoethyl cellulose and Sepharose-6B column chromatography of CPs generated several fractions. Total glucan content was determined in all the fractions. The F1 fraction displayed the highest sugar content and was considered as a purified polysaccharide (PP). The total glucan and β-glucan content in the four fractions ranged between 76.85-2.95% and 75.08-1.46%, respectively. The yield of the PPs was 300 mg, and it was obtained as a white powder. The PPs were characterized by Fourier-transform infrared spectroscopy (FTIR) and thin-layer chromatography. The FTIR spectral details confirmed the presence of a xylopentose polysaccharide. The antioxidant activity of the PPs was evaluated using in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging assay and superoxide radical scavenging assay. The PPs showed strong DPPH free radical and superoxide anion radical scavenging activities in a dose-dependent manner. Purified PPs free of phenolics, protein, and carbohydrates were mainly responsible for the radical scavenging activity. The data suggest the potential of PPs as natural antioxidants.

• Journal of the Korean Society of Radiology
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• v.15 no.1
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• pp.71-78
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• 2021

When continuous X-ray are used when acquiring and X-ray image, even the same material may not be accurately represented in the image according to the thickness due to various X-ray energies. To solve this problem, the X-ray energy spectrum was changed to improve the image quality. Using SPEKTR v3.0, an X-ray energy spectrum with an additional filter added and a general X-ray energy spectrum using only a unique filter were obtained. Simulation was performed using the obtained X-ray energy spectrum as a radiation source for Geant4 Application for Tomographic Emission (GATE). Using GATE data, an X-ray image with an additional filter and an image reconstructed from and X-ray image without an additional filter were compared and analyzed through a mono energy image of 74 keV. In the case of using the X-ray energy spectrum without using an additional filter, the amount of X-rays transmitted according to the thickness of the same material is different from the amount that decreases according to the thickness of the material. Similar results were obtained as the amount decreased with the material thickness. In other words, a similar result was obtained when the reduced dose was used with a mono energy. When an X-ray image is obtained by changing an X-ray energy spectrum using an additional filter, a more accurate result of transmission of X-rays may be obtained. In radiological examination, it was confirmed that the appropriate use of the additional filter has a great effect on improving the image quality.

• Journal of the Korean Society of Radiology
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• v.16 no.3
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• pp.203-209
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• 2022

One of the typical methods for lowering radiation dose while maintaining image quality of computed tomography (CT) is the use of model-based iterative reconstruction (MBIR). This study is to evaluate the image quality by adjusting the strength of the advanced modeled iterative reconstruction (ADMIRE), which is well known as a representative model of MBIR. The study was conducted using phantom, and CT images were obtained while adjusting the strength of ADMIRE in units of 1 to 5. Quantitative evaluation includes noise levels using coefficient of variation (COV) and contrast to noise ratio (CNR), as well as natural image quality evaluation (NIQE) and blind/referenceless image spatial quality evaluator (BRISQUE). As a result, in both noise level and blind quality evaluation results, the higher the strength of ADMIRE, the better the results were derived. In particular, it was confirmed that COV and CNR were improved 1.89 and 1.75 times at ADMIRE 5 compared to ADMIRE 1, respectively, and NIQE and BRISQUE were proved to be improved 1.35 and 1.22 times at ADMIRE 5 compared to ADMIRE 1, respectively. In conclusion, this study was proved that the reconstruction strength of ADMIRE had a great influence on the noise level and overall image quality evaluation of CT images.