• Korean Journal of Cognitive Science
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• 제20권2호
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• pp.125-154
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• 2009

This paper describes the possibility of human physiological data, especially brain-wave activity, to detect cognitive overload, a phenomenon that may occur while learner uses an e-learning system. If it is found that cognitive overload to be detectable, providing appropriate feedback to learners may be possible. To illustrate the possibility, while engaging in cognitive activities, cognitive load levels were measured by EEG (electroencephalogram) to seek detection of cognitive overload. The task given to learner was a computerized listening and recall test designed to measure working memory capacity, and the test had four progressively increasing degrees of difficulty. Eight male, right-handed, university students were asked to answer 4 sets of tests and each test took from 61 seconds to 198 seconds. A correction ratio was then calculated and EEG results analyzed. The correction ratio of listening and recall tests were 84.5%, 90.6%, 62.5% and 56.3% respectively, and the degree of difficulty had statistical significance. The data highlighted learner cognitive overload on test level of 3 and 4, the higher level tests. Second, the SEF-95% value was greater on test3 and 4 than on tests 1 and 2 indicating that tests 3 and 4 imposed greater cognitive load on participants. Third, the relative power of EEG gamma wave rapidly increased on the 3rd and $4^{th}$ test, and signals from channel F3, F4, C4, F7, and F8 showed statistically significance. These five channels are surrounding the brain's Broca area, and from a brain mapping analysis it was found that F8, right-half of the brain area, was activated relative to the degree of difficulty. Lastly, cross relation analysis showed greater increasing in synchronization at test3 and $4^{th}$ at test1 and 2. From these findings, it is possible to measure brain cognitive load level and cognitive over load via brain activity, which may provide atimely feedback scheme for e-learning systems.

• Korean Journal of Agricultural and Forest Meteorology
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• 제23권4호
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• pp.329-339
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• 2021

Soybeans (Glycine max), one of major upland crops, require precise management of environmental conditions, such as temperature, water, and soil, during cultivation since they are sensitive to environmental changes. Application of spectral technologies that measure the physiological state of crops remotely has great potential for improving quality and productivity of the soybean by estimating yields, physiological stresses, and diseases. In this study, we developed and validated a soybean growth prediction model using multispectral imagery. We conducted a linear regression analysis between vegetation indices and soybean growth data (fresh weight and LAI) obtained at Miryang fields. The linear regression model was validated at Goesan fields. It was found that the model based on green ratio vegetation index (GRVI) had the greatest performance in prediction of fresh weight at the calibration stage (R²=0.74, RMSE=246 g/m², RE=34.2%). In the validation stage, RMSE and RE of the model were 392 g/m² and 32%, respectively. The errors of the model differed by cropping system, For example, RMSE and RE of model in single crop fields were 315 g/m² and 26%, respectively. On the other hand, the model had greater values of RMSE (381 g/m²) and RE (31%) in double crop fields. As a result of developing models for predicting a fresh weight into two years (2018+2020) with similar accumulated temperature (AT) in three years and a single year (2019) that was different from that AT, the prediction performance of a single year model was better than a two years model. Consequently, compared with those models divided by AT and a three years model, RMSE of a single crop fields were improved by about 29.1%. However, those of double crop fields decreased by about 19.6%. When environmental factors are used along with, spectral data, the reliability of soybean growth prediction can be achieved various environmental conditions.

• Applied Biological Chemistry
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• 제15권1호
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• pp.85-92
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• 1972

The field experiment was performed to investigate the effects of various kinds of phosphorus fertilizers such as double superphosphate, fused magnesium phosphate and Simagcarin (both the Kyun-gi Chemical Co, products) on the physiological roles in development of root system, growth and yield compositions of rice plant. Radioactive phosphoric acid $(H_3\;^{32}PO_4)$ was applied to measure the root activity. 1. The number of total tillers was significantly increased in double superphosphate plots, but the rate of fruitful tillers was more numerous in the fused magnesium phosphate and the Simagcarin plots than that of the other plots. 2. The grain yield was much more obtained in the fused magnesium phosphate and Simagcarin plots (no significant difference were found between both of plots) than the double superphosphate and control plots. It seemed due to the increasing of seedbearing rate and number of fruitful tillers. 3. In double superphosphate plots, root system was mostly developed near topsoil areas, but fused magnesium phosphate and the Simagcarin plots, root system was uniformly distributed from topsoil to subsoil areas. 4. As the results of those experiments, fused magnesium phosphate and Simagcarin was demonstrated to be soil amendmentical materials rather than the phosphorus fertilizers, especially in low productive paddy soils which lack the special mineral nutritions.

• Journal of Life Science
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• 제22권6호
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• pp.837-843
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• 2012

This study was carried out to investigate the morphological and physiological characteristics of six new cultivars of Hypsizygus marmoreus (Hm) and measure endo-, exo-cellular enzyme-specific activity. The domestic wild stain (Hm3-10) and commercial strain in Japan (Hm1-1) were mated by crossing monokaryon mycelia. We gained 58 strains from one of 400 crosses through the $1^{st}$ cultivation experiment, and selected six strains from one of 58 strains through the $2^{nd}$ cultivation experiment. When six of the selected new strains were grown during several spawn culture periods (60, 70, 80, 90, and 100 days), a spawn culture period of more 80 days was considered to be excellent as being shorter than 19~20 days. Therefore, we determined the period of spawn culture as 80 days. Three strains such as Hm15-3, Hm15-4, and Hm17-5 showed an excellent result. When endo-cellular enzyme activity measured eight strains, we obtained a result of that specific activity of ${\alpha}$-amylase at the highest as 73.9~102.2 unit/mg protein, and chitinase is lower than ${\alpha}$-amylase at 8.1~13.1 unit/mg protein. When exo-cellular enzyme activity measured eight strains, we determined the result of that specific activity of ${\alpha}$-amylase is the highest at 5,292~1,184 unit/mg protein, and CMCase and xylanase were 1,140~245 unit/mg protein, 94~575 unit/mg protein, compared to each other. However, the enzyme activity of ${\beta}$-glucosidase and chitinase is low.

• Journal of the Korean Applied Science and Technology
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• 제35권1호
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• pp.263-272
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• 2018

The object of this study was to measure the bioactivity and lipid peroxidation inhibition activity of peel from Gardenia jasminoides Ellis fructus (GJE) in Namhae Korea. The amount of phytic acid was also determined. Extraction was performed using three solvents, CM (choloform:methanol, 2:1, v/v), n-butanol and 70% ethanol. To investigate by the solvent extract of total phenol content and value as a functional food ingredient of GJE peel through nitrogen oxide scavenging activity, antioxidant activity, reducing power and lipid peroxidation inhibition were performed. The bioactivities of the extract solvents increased significantly with increasing concentrations (0.2, 0.4, 0.6 mg/mL, p<0.05). The total phenol contents of GJE peel extracts were highest in CM ($39.74{\pm}0.15mg\;CAE/g$) extract. The order of total phenol contents, antioxidant activity and reducing power of the solvents in the GJE peel were the same, in the analysis of nitrogen oxides scavenging activity and lipid peroxidation inhibition, it was confirmed the results were inconsistent. As a result, the GJE peel showed excellent bioactivities. Considering the extraction yield and various physiological activities, it is considered that efficiency is better when extracted from CM and 70% ethanol extracts.

• Korean Journal of Agricultural Science
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• 제25권1호
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• pp.52-67
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• 1998

The investigative research on the mammalian milk purely consisted of the physiological quality of lactoferrin was conducted to reveal the antimicrobial ativity of specifically functional foods with antibiotic characteristics as a basic data in food manufacturing. Bovine lactoferrin were isolated from raw milk samples, and was digested with pepsin, trypsin and chymotrypsin. It was necessary then to separate and purify lactoferrin from bovine raw milk, and in order to analyze the antimicrobial activity of the enzyme-treated bovine lactoferrin in their required quantitative fraction. Afterwards Escherichia coli and Staphylococcus aureus was incubated in it. It was that investigated to enzyme-treated fractions molecular weight and the peptide fragment with antimicrobial effect. 1. The purity of enzyme-treated bovine lactoferrin(BLF) was tested by SDS-PAGE. As a results of 12% SDS-PAGE assay, pepsin-treated LF did not exhibited band until if reaches 14 KDa, while trypsin and chymotrypsin treated LF, known to contain the non-digestive lactoferrin exhibited band at a molecular weight of 33 KDa. 2. Bovine lactoferrin was sucessfully purified through the use of Sephadex G-50 Column. In order to assay LF through the Sephadex G-50 column chromatography, the digestive bovine lactoferrin (BLFs) was eluted with a linear gradient of 0.05% Tris-HCl. When the gel-filtration analysis, pepsin, trypsin and chymotrypsin treatments of BLF fragments was showed 2, 3, and 2 peak, respectively. The results of the HPLC analysis confirmed that had a non-digestive lactoferrin receptor, and trypsin and chymotrypsin treated BLFs has an antimicrobial effect. 3. To measure the strength of the antimicrobial effect of enzyme treated lactoferrin it was compared to the antimicrobial activity taking place at the incubated Escherichia coli and Staphylococcus aureus. This might explain the resistance of the microorganisms for peptide fragment. The pepsin-treated of bovine lactoferrin was markedly reduced by incubation of the cells. Trypsin-treated of BLF was similar to chymotrypsin-treated of BLF. However, trypsin and chymotrypsin treatments of BLFs were showed the antimicrobial effect until eight hours incubation for native bovine lactoferrin. Therefore the enzyme-treated lactoferrin have an antimicrobial effect even non-digestive lactoferrin. 4. The digestive bovine lactoferrin fragments assay was carried out by the use of Sephadex G-50 column chromatography and SDS-PAGE. The pepsin and chymotrypsin-treated fragments has a low molecular weight and trypsin-treated lactoferrin was only showed a band. It was described that characteristics of digestive protein. It appeared that there may be a relation between virulence and resistance to enzyme-treated BLF.

• The Korean Journal of Physiology
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• 제3권2호
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• pp.9-16
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• 1969

It is well known that a number of -SH and -SS containing substances afford a certain measure of protection against radiation effects in many biological systems, and it is conceivable that inherent -SH levels in Ehrlich ascites tumour (ELD)cells may be of decisive improtance with respect to the development of cellular radiation injury. So far, little effort has been directed to elucidate the changes in levels of different -SH and -SS groups in ELD cells when the tumour-bearing whole animal was subjected to the sublethal dose of X-irradiation. The present study was designed to bring some lights in the possible changes of and relationship between various sulfhydryl levels, such as P-SH, NP-SH and NP-SS, as well as the content of protein and cell volume of ELD cells, after subjecting the ELD mice to 1,200 r of X-irradiation. The animals used in this experiment were all mixed bred mice of $20{\sim}25\;gm$ in body weight (approximately 2 months old) irrespective of sex. 12 mice in one experiment were inoculated intraperitoneally with 0.2 ml of ascites tumour cells $(2{\times}10^6\;cells)$, and on the 7th day of the tumour growth, they were X-irradiated with 1,200 r, using the conventional X-ray machine under the following conditions: 200 Kv at 15 mA, 0.5 mm Cu filter, target-skin distance: 50 cm. Radiation dose was measured with the the Philip integrating dosimeter. At 24, 36, 48 and 60 hours after the X-irradiation, the mice were killed by cervical dislocation, and the tumours were taken out. Freshly withdrawn ascites tumours were placed in ice, and immediately the cell concentration was measured with the Coulter Cell Counter (Model B), and the hematocrit of the tumour cells were also determined. Cell volume was thus calculated by the cell concentration and hematocrit value. P-SH content of ELD cells was measured potentiometrically according to the method of Calcutt & Doxey, and NP-SH and NP-SS contents were measured spectrophotometrically by the method described by Ellman. Protein content of ELD cells was determined with the Folin phenol reagent by Lowry et al. Altogether, 48 experimental mice were used, and 12 mice with the only exception of X-irradiation were used as the control. Results obtained indicate that the contents of all the cellular sulfhydryl groups as well as cell volume and protein content of the ELD cells increase significantly as time progresses after the sub-lethal X-ray dose of 1,200 r was given and that all the increase is in a lineal fashion. The regression lines of the relative values, (i. e., taking each control value as 1) of all the values obtained, and the regression lines of cell volume, protein and NP-SH are identical, whereas those of NP-SS and P-SH appear to be widely seperated. However, the difference of those two lines (NP-SS & P-SH) were found to be not significant statistically (p>0.05). Therefore, it can be concluded from the above results that all the values examined increase in a lineal fashion with no statistically significant difference among them. Also, with the radiation dose of 1,200 r, the ELD cell becomes enlarged and swollen progressively up to 60 hours post-irradiation and it becomes more than two times of the original normal size at 60 hours after the irradiation, and up to this stage, it seems apparent that the cell division has been slow due to the X-irradiation applied in this experiment. It is well understandable that the contents of NP-SH, NP-SS, P-SH and protein of the ELD cells increase in parallel with the increase of the cell volume by the X-ray does used, but it also seems interesting to note that all the cellular substances tested show no appreciable difference in the pattern of increase.

• Food Science and Preservation
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• 제16권1호
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• pp.101-108
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• 2009

The purpose of this study was to measure flavonoid and polyphenol contents, and physiological activities of various extracts from Vitex rotundifolia seeds (known as Man Hyung Ja). We obtained three extracts using water (WE), ethanol (EE) and hot water (HWE). The EE sample had the highest flavonoid content of 31.05 mg/g. Polyphenol contents of WE and HWE were 186.69 mg/g and 182.55 mg/g, respectively. HWE had the highest superoxide dismutase (SOD)-like activity, at 83.40%. The electron donating abilities (EDA) were $91.14{\sim}95.97%$ at the concentration of 1.0 mg/mL, and all of extracts showed more than 88% EDA even at a concentration of 0.1 mg/mL. The inhibitory rates of xanthine oxidase were $94.02{\sim}97.51%$ when 1.0 mg/mL extracts were used, and all extracts showed more than 90% inhibition at 0.5 mg/mL. The nitrite scavenging abilities were $59.27{\sim}86.61%$ at pH 1.2 and 1.0 mg/mL extract concentration; these abilities decreased as pH increased. Tyrosinase inhibition activities of HWE and WE were 48.58% and 46.67%, respectively. These results indicate that Vitex rotundifolia seeds extract might be an effective antioxidative activity.

• The Korean Journal of Physiology
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• 제22권1호
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• pp.63-77
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• 1988

This study was carried out to investigate relationships between maximal running time (MRT) and glycogen supercompensation in fast twitch white fibers (white vastus, WV), fast twitch red fibers (red vastus, RV) and slow twitch red fibers (soleus muscle, SM) of endurance-trained rats. Male rats of a Sprague-Dawley strain were divided into the trained groups and untrained groups. Untrained groups were acquired to run on the treadmill 10 minutes for 3 days and remained rest and maintained with mixed diet for 4 weeks. For last 10 days of resting period, the untrained rats were divided into 3 groups i.e. mixed diet (untrained control), high and low carbohydrate (CHO) diet groups. And each group was subdivided into 2 groups, one group was tested for the MRT and the other was sacrificed to measure the blood glucose, blood lactate, glycogen contents of liver and muscles. The experimental groups were trained on treadmill by a modified method of Constable et al. (1984) maintained with mixed diet for 4 weeks. After measurement of MRT of this group, they were also divided into high and low CHO groups and fed with these diet for 2 days and MRT of each group was measured again to see the effect of high or low CHO feeding on the MRT. Each group was maintained with the same diet for next 2 days during which some of the rats were sacrificed at given time intervals for the measurements of blood glucose and lactate, liver and the muscles glycogen. The results were summarized as follows; 1) In the untrained group, there were no significant differences between subgroups in MRT, glycogen conent of SM, RV and WV. But blood glucose concentration and glycogen content of liver of low CHO group were significantly lower than those of mixed diet group. 2) The MRT and glycogen content of SM, RV and WV of trained mixed diet group were significantly increased compared to those of untrained mixed diet group, but there was no significant difference in glycogen content of liver. 3) MRT of trained mixed, high CHO and low CHO groups were $137{\pm}9.8,\;176{\pm}9.8\;and\;129{\pm}7.3\;min$ respectively with the significant difference between them. 4) There were no differences in blood lactate concentrations between the trained high and low CHO groups immediately after maximal running and during recovery period. 5) Glycogen contents in RV and SM of trained high CHO group were significantly increased, and glycogen contents in RV, WV and liver of trained low CHO group were significantly decreased compared to those of trained mixed diet group. 6) Immediately after maximal running, the blood glucose concentrations of trained high CHO and low CHO groups were $73{\pm}4.0\;and\;67{\pm}6.9mg%$ respecitively. The blood glucose of the trained high CHO group was fully recovered within one hour by feeding. But blood glucose concentration of low CHO group was slowly recovered up to $114{\pm}4.1mg%$ after two hours of feeding and maintained. Those values were still significantly lower than that of trained mixed diet group. The synthetic rates of glycogen in liver and muscles during the recovery period followed the similar time course of the blood glucose recoveries in each group. These results suggest that an increase in MRT of trained high CHO group was attributed to the glycogen supercompensation in slow twitch muscle fibers. And a decrease in MRT of trained low CHO may be due to decreased glycogen contents of liver and muscles. The results also suggest that glycogen supercompensation was more evident in slow twitch red fibers of endurance-trained rats and blood glucose is one of the limiting factors of glycogen synthesis.

• Journal of Physiology & Pathology in Korean Medicine
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• 제20권4호
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• pp.844-852
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• 2006

This study was to evaluate the effect of Yeongyupaedog-san (YGPDS) on mouse Thl and Th2 cells' differentiation and ovalbumin (OVA)-induced allergic inflammation. The proliferation of mouse CD4 T cells and the secretion of Th1/Th2 cytokines under the influence of YGPDS extract were measured as well as the amount of ${\beta}-hexosaminidase$ in RBL-2H3 cells and the levels of $TNF-{\alpha}$ and 1L-6 secretion in Raw264.7 cells. BALB/c mice were orally administered with YGPDS extract and simultaneously inoculated with OVA to induce allergic reaction and measure the level of total IgE, OVA-specific IgE and the production of IFN- g, IL-4, IL-5 by the spleen cells. When mouse CD4 T cell were stimulated with anti-CD3 and anti-CD28 for 48 hours in various concentrations of YGPDS extract, it increased proliferation of CD4 cells by 11% in $100\;{\mu}g/^{ml}$ concentration but it showed an inhibition by 37% at $200\;{\mu}g/^{ml}$ CD4 T cells under Th1/Th2 polarizing conditions for 3 days with YGPDS resulted in mild decrease of IFN- g in Thl cells and significant decrease of IL-4 in Th2 cells at $500\;{\mu}g/^{ml}\;and\;100\;{\mu}g/^{ml}$ by 18% and 21%, respectively. YGPDS extract had a dose-dependent inhibitory effect on antigen-induced release of ${\beta}-hexosaminidase$ in RBL-2H3 cells. Treatment of YGPDS extract on LPS stimulated Raw 264.7 cells showed dose-dependent decrease in TNF-n production. Oral administration of YGPDS extract on OVA-induced allergic mice showed an inhibitory effect on the levels of total serum IgE and OVA-specific IgE by 25% and 34% , respectively. Culture of spleen cells with OVA resulted in significant increase of IFN- g by 44% and significant decrease of IL-4 and IL-5 by 56%, and 24%, respectively. The results show that YGPDS does not strongly induce mouse T cells to transform into Thl or Th2 but it has an anti-allergic effect in vitro, and that it also corrects the unbalance between the reactions of Th cells in allergic diseases.