• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.67-83
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• 1997

In order to search for anti-influenza virus type A agents from Korean medicinal herbs, we selected 100 medicinal herbs, based on a review of the Korean traditional medicine books. Four of 100 Korean medicinal herbs, MM-40, MM-55, MM-63, MM-110, exhibited very strong anti-influenza virus activity. The fractions of four medicinal herbs, which had very strong anti-influenza virus activity, were tested for antiviral activity by means of Haemagglutination inhibition test(HTT), 40% MeOH fraction of MM-40, $H_2O$ fraction of MM-55, 20% fraction of MM-63 3nd $H_2O$ fraction of MM-110 had strong anti-influenza virus activity at the range of $78{\mu}g/ml$ to $156{\mu}g/ml$, 1.56mg/ml to 100mg/ml, 6.25mg/ml to 50mg/ml and $48.7{\mu}g/ml$ to $780{\mu}g/ml$, respectively. These results of HIT indicated that fractions of Korean medicinal herbs might inhibit either attachment of virus to cell surface receptor or penetration of virus into cell during the initial stage of infection. In the cytotoxicity of fractions against red blood cells, 40% MeOH fraction of MM-40, 20% fraction of MM-63 and $H_2O$ fraction of MM-110 showed cytotoxicity at the range of $78{\mu}g/ml$ to 10mg/ml, 50mg/ml to 100mg/ml and $195{\mu}g/ml$ to 100mg/ml, respectively, whereas $H_2O$ fraction of MM-55 did not show cytotoxicity. In order to establish influenza virus adapted animal model, influenza virus type A were passaged 3 and 4 times successively in Balb/c mouse. As a result, we had 4 HA unit titers on the 5 days of 3rd passages and 7 days of 4th passages after infection, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.480-486
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• 2004

Despite many therapeutic advances in the understanding of the processes in carcinogenesis, overall mortality statistics are unlikely to change until there is reorientation of the concepts for the use of natural products as new anticarcinogenic agents. In this study, we investigated the anticarcinogenic activity, antioxidant and DPPH scavenging activity of Sargassum fulvellum (SF). SF was extracted with methanol, which was further fractionated into five different types: hexane (SFMH), ethylether (SFMEE), ethyl acetate (SFMEA), butanol (SFMB) and aqueous (SFMA) partition layers. We determined the cytotoxic effect of these layers on human cancer cells by MTT assay. Among various partition layers of SF, at starting concentration of 100 $\mu\textrm{g}$/mL, SFMEE showed very high cytotoxicity which were 92, 90 and 84% and kept high throughout 5 concentration levels sparsed by 100 $\mu\textrm{g}$/mL against all three human cancer cell lines: HepG2, HT-29 and HeLa. SFMEA showed a low cytotoxicity at the beginning concentration level, but as the concentration became denser, growth inhibition effect of cancer cell lines started to increase and at 500 $\mu\textrm{g}$/mL, it hit the highest, which were 91, 96 and 98% against the same three cell lines as above. We observed QR induced effect in all fraction layers of SF. SFMEE showed similar tendensy of QR induced effect as did against cytotoxicity. The QR induced effect of SFMEE on HepG2 cells at 25 $\mu\textrm{g}$/mL concentration indicated 3 times higher than the control value of 1.0 and SFMH tended to be concentration-dependent on HepG2 cells. At 100 $\mu\textrm{g}$/mL, the QR induced effects resulted a ratio, which was 2.5 times higher than the control value. In search for antioxidation effects of SF extract and partition layer, the reducing activity on the 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging potential was sequentially screened. The SFM has similar antioxidant activity as to BHT and vitamin C groups.

• Journal of Life Science
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• v.25 no.8
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• pp.953-959
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• 2015

Optogenetics is the combination of optical and molecular strategies to control designated molecular and cellular activities in living tissues and cells using genetically encoded light-sensitive proteins. It involves the use of light to rapidly gate the membrane channels that allows for ion movement. Optogenetics began with the placing of light-sensitive proteins from green algae inside specific types of brain cells. The cells can then be turned on or off with pulses of blue and yellow light. Using the naturally occurring algal protein Channelrhodopsin-2 (ChR2), a rapidly gated light-sensitive cation channel, the number and frequency of action potentials can be controlled. The ChR2 provides a way to manipulate a single type of neuron while affecting no others, an unprecedented specificity. This technology allows the use of light to alter neural processing at the level of single spikes and synaptic events, yielding a widely applicable tool for neuroscientists and biomedical engineers. An improbable combination of green algae, lasers, gene therapy and fiber optics made it possible to map neural circuits deep inside the brain with a precision that has never been possible before. This will help identify the causes of disorders like depression, anxiety, schizophrenia, addiction, sleep disorder, and autism. Optogenetics could improve upon existing implanted devices that are used to treat Parkinson’s disease, obsessive-compulsive disorder and other ailments with pulses of electricity. An optogenetics device could hit more specific subsets of brain cells than those devices can. Applications of optogenetic tools in nonneuronal cells are on the rise.

• Interdisciplinary Bio Central
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• v.1 no.3
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• pp.9.1-9.6
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• 2009

Introduction: In the mass spectrometry-based proteomics, biological samples are analyzed to identify proteins by mass spectrometer and database search. Database search is the process to select the best matches to the experimental mass spectra among the amino acid sequence database and we identify the protein as the matched sequence. The match score is defined to find the matches from the database and declare the highest scored hit as the most probable protein. According to the score definition, search result varies. In this study, the difference among search results of different search engines or different databases was investigated, in order to suggest a better way to identify more proteins with higher reliability. Materials and Methods: The protein extract of human mesenchymal stem cell was separated by several bands by one-dimensional electrophorysis. One-dimensional gel was excised one by one, digested by trypsin and analyzed by a mass spectrometer, FT LTQ. The tandem mass (MS/MS) spectra of peptide ions were applied to the database search of X!Tandem, Mascot and Sequest search engines with IPI human database and SwissProt database. The search result was filtered by several threshold probability values of the Trans-Proteomic Pipeline (TPP) of the Institute for Systems Biology. The analysis of the output which was generated from TPP was performed. Results and Discussion: For each MS/MS spectrum, the peptide sequences which were identified from different conditions such as search engines, threshold probability, and sequence database were compared. The main difference of peptide identification at high threshold probability was caused by not the difference of sequence database but the difference of the score. As the threshold probability decreases, the missed peptides appeared. Conversely, in the extremely high threshold level, we missed many true assignments. Conclusion and Prospects: The different identification result of the search engines was mainly caused by the different scoring algorithms. Usually in proteomics high-scored peptides are selected and low-scored peptides are discarded. Many of them are true negatives. By integrating the search results from different parameter and different search engines, the protein identification process can be improved.

• Food Science and Preservation
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• v.13 no.6
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• pp.796-802
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• 2006

In order to investigate the anti-inflammatory and cellular protective effects of Atractomorpha lata Motschulsky, Oxya japonica japonica Thunberg and Stethophyma magister Rehn, we first examined hydrogen peroxide-induced cytotoxicity in SH-SY5Y cells as well as antioxidant assays including DPPH and FRAP assays. We found that water, ethanol and methanol extracts of Oxya japonica japonica Thunberg and Stethophyma magister Rehn had potentials to anti-oxidant activity and especially water extract of Oxya japonica japonica Thunberg exhibited the most potent protective effects against $H-2O_2$-induced cytotoxicity in SH-SY5Y cells by MTT assay. Taken Together, these findings indicate that water extract of Oxya japonica japonica Thunberg could be useful insect resources for agrobiotechnological or oriental medicinal purposes.

• The Korean Journal of Applied Statistics
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• v.35 no.4
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• pp.543-552
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• 2022

When frost occurs, crops are directly damaged. When crops come into contact with low temperatures, tissues freeze, which hardens and destroys the cell membranes or chloroplasts, or dry cells to death. In July 2020, a sudden sub-zero weather and frost hit the Minas Gerais state of Brazil, the world's largest coffee producer, damaging about 30% of local coffee trees. As a result, coffee prices have risen significantly due to the damage, and farmers with severe damage can produce coffee only after three years for crops to recover, which is expected to cause long-term damage. In this paper, we tried to predict frost using frost generation data and weather observation data provided by the Korea Meteorological Administration to prevent severe frost. A model was constructed by reflecting weather factors such as wind speed, temperature, humidity, precipitation, and cloudiness. Using XGB(eXtreme Gradient Boosting), SVM(Support Vector Machine), Random Forest, and MLP(Multi Layer perceptron) models, various hyper parameters were applied as training data to select the best model for each model. Finally, the results were evaluated as accuracy(acc) and CSI(Critical Success Index) in test data. XGB was the best model compared to other models with 90.4% ac and 64.4% CSI, followed by SVM with 89.7% ac and 61.2% CSI. Random Forest and MLP showed similar performance with about 89% ac and about 60% CSI.

• Strategy21
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• s.32
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• pp.192-221
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• 2013

In order to deal with the current economic crisis, the U.S. government, as a part of its austerity fiscal policy, implemented a budget sequester. The sequester will hit the U.S. defense budget the hardest, and as a result will most likely put the security of the international community in jeopardy. The U.S. will have to cut 46 billion dollars from its original 525 billon defense spending in 2013. And by the year 2022, will have to cut 486.9 billion dollars. Such an astronomical decrease in the U.S. defense spending will inevitably burden the friendly nations. According to recent studies, pirate related incidents in Somalia, where piracy is most active, has declined from its 226 incidents to 76 incidents per year in 2012, a 66% drop from previous years'. However, piracy threats as well as those related to firearms still remain and thus participants of anti-piracy operations, namely the U.S., U.K., France, Canada, NCC, EUNAVFOR, and NATO, are facing a problem of declining forces. Considering the current situation as well as rising expectations from the international community, Republic of Korea, a supporter of NCC's maritime security operation, not to mention its foremost duty of securing its sea, is at a stage to re-examine its operational picture. Such action will be a good opportunity for Republic of Korea to build the trust and live up to the international community's expectation. To quote from the network theory, although in relation to other friendly nations participating in the anti-piracy operation, Republic of Korea currently remains at a single cell level, this opportunity will certainly develop Korea to a 'node' nation in which power and information would flow into. Through this expansion of operational capability, Republic of Korea will be able to exert more influence as a more developed nation. Currently however, not only is the single 4,500 ton class destroyer deployed in Somalia a limited unit to further expand the scale and amount of force projection in the area, but also the total of six 4,500 ton class destroyers ROK feet possess is at a high fatigue degree due to standard patrolling operations, midshipman cruise and the RIMPAC exercise. ROK fleet therefore must consider expanding the number of ships deployed along with either deploying combat support ships or constructing logistics support site in the African region. Thus, by expanding its operational capabilities and furthermore by abiding to the rightful responsibilities of a middle power nation, Republic of Korea will surely earn its respect among the members of the international community.

• Radiation Oncology Journal
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• v.24 no.4
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• pp.280-284
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• 2006

$\underline{Purpose}$: To evaluate biological characteristics of neutron beam generated by MC50 cyclotron located in the Korea Institute of Radiological and Medical Sciences (KIRAMS). $\underline{Materials\;and\;Methods}$: The neutron beams generated with 15 mm Beryllium target hit by 35 MeV proton beam was used and dosimetry data was measured before in-vitro study. We irradiated 0, 1, 2, 3, 4 and 5 Gy of neutron beam to EMT-6 cell line and surviving fraction (SF) was measured. The SF curve was also examined at the same dose when applying lead shielding to avoid gamma ray component. In the X-ray experiment, SF curve was obtained after irradiation of 0, 2, 5, 10, and 15 Gy. $\underline{Results}$: The neutron beams have 84% of neutron and 16% of gamma component at the depth of 2 cm with the field size of $26{\times}26\;cm^2$, beam current $20\;{\mu}A$, and dose rate of 9.25 cGy/min. The SF curve from X-ray, when fitted to linear-quadratic (LQ) model, had 0.611 as ${\alpha}/{\beta}$ ratio (${\alpha}=0.0204,\;{\beta}=0.0334,\;R^2=0.999$, respectively). The SF curve from neutron beam had shoulders at low dose area and fitted well to LQ model with the value of $R^2$ exceeding 0.99 in all experiments. The mean value of alpha and beta were -0.315 (range, $-0.254{\sim}-0.360$) and 0.247 ($0.220{\sim}0.262$), respectively. The addition of lead shielding resulted in no straightening of SF curve and shoulders in low dose area still existed. The RBE of neutron beam was in range of $2.07{\sim}2.19$ with SF=0.1 and $2.21{\sim}2.35$ with SF=0.01, respectively. $\underline{Conclusion}$: The neutron beam from MC50 cyclotron has significant amount of gamma component and this may have contributed to form the shoulder of survival curve. The RBE of neutron beam generated by MC50 was about 2.2.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.1
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• pp.1-9
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• 2006

Regardless of the recent observed warmer winters in Korea, more freeze injuries and associated economic losses are reported in fruit industry than ever before. Existing freeze-frost forecasting systems employ only daily minimum temperature for judging the potential damage on dormant flowering buds but cannot accommodate potential biological responses such as short-term acclimation of plants to severe weather episodes as well as annual variation in climate. We introduce 'dormancy depth', in addition to daily minimum temperature, as a complementary criterion for judging the potential damage of freezing temperatures on dormant flowering buds of grape vines. Dormancy depth can be estimated by a phonology model driven by daily maximum and minimum temperature and is expected to make a reasonable proxy for physiological tolerance of buds to low temperature. Dormancy depth at a selected site was estimated for a climatological normal year by this model, and we found a close similarity in time course change pattern between the estimated dormancy depth and the known cold tolerance of fruit trees. Inter-annual and spatial variation in dormancy depth were identified by this method, showing the feasibility of using dormancy depth as a proxy indicator for tolerance to low temperature during the winter season. The model was applied to 10 vineyards which were recently damaged by a cold spell, and a temperature-dormancy depth-freeze injury relationship was formulated into an exponential-saturation model which can be used for judging freeze risk under a given set of temperature and dormancy depth. Based on this model and the expected lowest temperature with a 10-year recurrence interval, a freeze risk probability map was produced for Hwaseong County, Korea. The results seemed to explain why the vineyards in the warmer part of Hwaseong County have been hit by more freeBe damage than those in the cooler part of the county. A dormancy depth-minimum temperature dual engine freeze warning system was designed for vineyards in major production counties in Korea by combining the site-specific dormancy depth and minimum temperature forecasts with the freeze risk model. In this system, daily accumulation of thermal time since last fall leads to the dormancy state (depth) for today. The regional minimum temperature forecast for tomorrow by the Korea Meteorological Administration is converted to the site specific forecast at a 30m resolution. These data are input to the freeze risk model and the percent damage probability is calculated for each grid cell and mapped for the entire county. Similar approaches may be used to develop freeze warning systems for other deciduous fruit trees.