• Title/Summary/Keyword: environmental temperature

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Catalytic Spectrophotometry for the Determination of Manganese at Trace Levels by a Novel Indicator Reaction (새로운 지시약 반응에 의해 극미량 수준의 망간 측정을 위한 촉매 반응의 분광 광도 측정법)

  • Gurkan, Ramazan;Caylak, Osman
    • Journal of the Korean Chemical Society
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    • v.54 no.5
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    • pp.556-566
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    • 2010
  • A new kinetic spectrophotometric method is developed for the measurement of Mn(II) in natural water samples. The method is based on the catalytic effect of Mn(II) with the oxidation of Gallocyanin by $KIO_4$ using nitrilotriacetic acid (NTA) as an activation reagent at 620 nm. The optimum conditions obtained are $4.00{\times}1^{-5}\;M$ Gallocyanin, $KIO_4$, $1.00{\times}10^{-4}\;M$ NTA, 0.1 M HAc/NaAc buffer of pH = 3.50, the reaction time of 5 min and the temperature of $30^{\circ}C$. Under the optimum conditions, the proposed method allows the measurement of Mn(II) in a range of $0.1\;-\;4.0\;ng\;mL^{-1}$ and with a detection limit of down to $0.025\;ng\;mL^{-1}$. The recovery efficiency in measuring the standard Mn(II) solution is in a range of 98.5 - 102%, and the RSD is in a range of 0.76 - 1.25%. The newly developed kinetic method has been successfully applied to the measurement of Mn(II) in both some environmental water samples and certified standard reference river water sample, JAC-0031 with satisfying results. Moreover, few cations and anions interfere with the measurement of Mn(II). Compared with the other catalytic-kinetic methods and instrumental methods, the proposed kinetic method shows fairly good selectivity and sensitivity, low cost, cheapness, low detection limit and rapidity. It can easily and successfully be applied to the real water samples with relatively low salt content and complex matrices such as bottled drinking water, cold and hot spring waters, lake water, river water samples.

Propagation Efficiencies at Different LED Light Qualities for Leaf Cutting of Six Echeveria Cultivars in a Plant Factory System (에케베리아 6품종의 엽삽 시 식물공장시스템 내 LED 파장에 따른 번식 효율)

  • Kim, Seongmin;Kim, Jiseon;Oh, Wook
    • Journal of Bio-Environment Control
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    • v.27 no.4
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    • pp.363-370
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    • 2018
  • The succulent plants of Echeveria genus are in increasing demand worldwide, but it is difficult to supply good quality young plants throughout the year because propagation efficiencies are depend on cultivar and environmental factors. This study was carried out to investigate the propagation efficiencies of leaf cutting in Echeveria cultivars at different LED light qualities in a closed-type plant factory system. Leaf cuttings cut from stock plants of six difficult-to-propagated cultivars 'Afterglow (AG)', 'Berkeley Light (BL)', 'Mason (MS)', 'Subsessilis Light (SL)', 'Cream Tea (CT)', and 'Ben Badis (BB)' were put into cutting media in the plant factory system maintained at a temperature of $24{\pm}2^{\circ}C$ and relative humidity of $60{\pm}10%$, and watered with over-head irrigation twice a week. Cuttings were irradiated with sole or mixed red (R, 660 nm), blue (B, 450 nm), green (G, 530 nm), and far-red (FR, 730 nm) LEDs as follows: R10, R8+B2, R5+B5, R7+B2+FR1, and R7+B2+G1. PPFD just above the cuttings was $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and photoperiod was 16/8 (light/dark) hours. As a result, propagation efficiencies were dependent on cultivar. Rooting and shooting were relatively easy in 'SL' but shoot formation in 'AG' was very difficult. Light qualities from LEDs also affected plant regeneration. Light conditions with a higher ratio of B, R5+B5, R7+B2+FR1, and R7+B2+G1, promoted shoot formation and growth but inhibited rooting and root growth. R10 and R8+B2 with a higher ratio of R promoted rooting and root growth and inhibited shoot formation and growth of cuttings. In addition, the treatment with FR increased leaf size and biomass of the all plants. Therefore, further studies are needed to investigate the optimum compositions of LED light quality for the improvement of leaf cutting efficiency in difficultto-propagated Echeveria cultivars.

Intermediate Culture of the Spat of Arkshell, Scapharca broughtonii in Summer (피조개, Scapharca broughtonii 부착치패의 하계 중간양성)

  • Min, Kwang-Sik;Kim, Byoung-Hak;Lee, Seung-Ju;Park, Ki-Yeol;Kim, Byung-Goun
    • The Korean Journal of Malacology
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    • v.20 no.2
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    • pp.125-130
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    • 2004
  • Arkshell, Scapharca broughtonii spats were placed in natural environmental condition for 30 days from July 28 to August 27, 2004, in order to estabilish intermediate culture technique. Growth and survival of the spats in different intermediate culture areas with various culture methods were measured. Water temperature of studied area ranged from 24.1 to 28.5$^{\circ}C$, salinity was 15.4 to 33.3 psu, dissolved oxygen was 3.92 to 12.6 mg/l. Scapharca broughtonii spats cultured in Yeosu developed the best, 10.15 ${\pm}$ 1.12 mm in average shell length, and the highest survival was recorded as 77% in Namhae. Shell lengths of the Scapharca broughtonii spats cultured in the water depths of 2, 5, and 10 m were 7.14 ${\pm}$ 1.14 mm, 6.98 ${\pm}$ 1.74 mm and 6.27 ${\pm}$ 1.33 mm, and the survivals showed 75.5%, 77.0% and 76.5%, respectively. When 1 mm, 2 mm, and 3 mm-sized spats were cultured for 30 days in water depth of 5 m, the shell length increased to 6.73 ${\pm}$ 1.46 mm, 6.98 ${\pm}$ 1.74 mm and 7.04 ${\pm}$ 1.19 mm, and survivals were 67.0%, 77.0% and 58.5%, respectively. The shell lengths of spat cultured for 30 days in mesh sizes of 1 ${\times}$ 1 mm, 2 ${\times}$ 2 mm and 3 ${\times}$ 3 mm, 5 m below the surface were 8.14 ${\pm}$1.23 mm, 8.26 ${\pm}$ 1.19 mm and 8.78 ${\pm}$ 1.16 mm, and survivals were 41.5%, 43.0% and 44.5%, respectively.

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Studies on the Epidemiology and Control of Bacterial Leaf Blight of Rice in Korea (한국에 있어서의 벼흰빛잎마름병의 발생생태와 방제에 관한 연구)

  • Lee Kyung-hee
    • Korean journal of applied entomology
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    • v.14 no.3 s.24
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    • pp.111-131
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    • 1975
  • The study has been carried out to investigate the occurrence, damage, characteristics of the pathogen, environmental conditions affecting the disease outbreak, varietal resistance, forecasting, and chemical control of bacterial leaf blight of rice in Korea since 1964. Bacterial leaf blight of rice became a major disease in Korea since 1960. A correlation was found between the annual increase of epidemics and increase of cultivation area of susceptible varieties, Jinheung, Keumnampung etc. Areal damage within the country showed that the more was at southern province, Jeonnam, Gyeongnam and western coast, and at flooded rice paddy. Yield reduction directly related with the amount of infection on upper leaves at heading stage. Fifty per cent of reduction resulted when the lesion area was more than 60 per cent. Less than 20 per cent of lesion area, however, was not affected so much on yield loss One hundred and six isolates collected from all over the country were classified as 8 strains by using 4 different bacteriophages in 1973. It was, however, only two in 1965. There were some specificities on varietal distributions among the strains such as that the Jinheung attacked mainly by strain A, B, C and I, those attack Kimmaze were A, B, H and I. Most strains were found from Tongil except D and E, whereas Akibare was only variety that attacked by strain E. Low temperature, high humidity, heavy rainfall and insutficient daylight favored the disease epidemics. Especially, typhoon and flooding at heading stage were critical factors. The earlier transplanting the more disease was resulted, and more nitrogen fertilizer application accerelated the diseased development in general. The resistance to the disease varied by growing stage of the sane plants. All of recommended varieties in Korea were susceptible to the disease except Norm No. 6 and Sirogane which moderately resistant. The pathogen, Xanthomonas oryzae, was detectable from extract of healthy seedlings that were grown in the field with an heavy infection previous year. The more bacteriophage in irigation water resulted the more disease outbreak, and the existence of more than 50 bacteriophages in 1ml. of irrigation water were necessary to initiate the disease out break. The curves representing occurrence of bacteriophages and disease outbreak were similar with 15 days interval. The survey of bacteriophage occurrence can be utilized in forecasting of the disease two weeks ahead of disease outbreak. Three applications of chemicals, Phenazin and Sangkel, in weekly intervals at the early satage of out-break depressed the symptom development, and increased yield by 20per cent. Proper period for the chemical application was just before the number of bacteriophage reaches 50 in 1ml. of irrigation water.

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Cooking and Pasting Characteristics of Non-Waxy and Waxy Pearled Barley Products from Korea (국내 시판 메성 및 찰성 보리쌀의 취반 및 호화특성)

  • Lee, Mi-Ja;Kim, Yang-Kil;Seo, Jae-Whan;Kim, Jung-Gon;Kim, Hyung-Soon
    • Food Science and Preservation
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    • v.16 no.5
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    • pp.661-668
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    • 2009
  • A total of 107 pearled barley products produced in Korea, 58 non-waxy and 49 waxy, were analyzed for protein and $\beta$-glucan content, whiteness, cooking characteristics (water absorption and expansibility), and pasting properties, with respect to the region of production. We compared non-waxy and waxy pearled barley products and sought correlations between levels of chemical components and cooking characteristics. Waxy pearled barley products had higher concentrations of protein (7.17-12.57%, w/w) and $\beta$-glucan (2.81-7.38%, w/w), a higher whiteness grade (27.1-49.6), and a greater water absorption (218-593%) and expansibility (366-593%) than did non-waxy barley products. The pasting temperature of non-waxy pearled barley ($73.9^{\circ}C$) was higher than that of waxy pearled barley ($66.9^{\circ}C$). Peak viscosity, hot paste viscosity, and final viscosity of non-waxy pearled barley products were higher than those of waxy products. The results showed that waxy pearled barley products had better cooking characteristics than did non-waxy products. A significant positive correlation was observed between protein and $\beta$-glucan content in both non-waxy and waxy pearled barley products ($r=0.632^{***}$ and $r=0.453^{**}$, respectively). Whiteness showed a negative correlation with protein content of both non-waxy and waxy pearled barley products ($r=-0.433^{***}$, $r=-0.343^{**}$). However, neither water absorption nor expansibility showed any significant correlation with protein or $\beta$-glucan content. The waxy ratio of 49 waxy pearled barley products ranged from 84-100%.

Characterization and Purification of the Bacteriocin Produced by Bacillus licheniformis Isolated from Soybean Sauce (간장에서 분리한 Bacillus licheniformis가 생산하는 박테리오신의 특성 및 정제)

  • Jung, Sung-Sub;Choi, Jung-I;Joo, Woo-Hong;Suh, Hyun-Hyo;Na, Ae-Sil;Cho, Yong-Kweon;Moon, Ja-Young;Ha, Kwon-Chul;Paik, Do-Hyeon;Kang, Dae-Ook
    • Journal of Life Science
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    • v.19 no.7
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    • pp.994-1002
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    • 2009
  • A bacteriocin-producing bacterium identified as Bacillus licheniformis was isolated from soybean sauce. Antibacterial activity was confirmed by paper disc diffusion method, using Micrococcus luteus as a test organism. The bacteriocin also showed antibacterial activities against Bacillus sphaericus, Lactobacillus bulgaricus, Lactobacillus planiarum, Paenibacillus polymyxa, and Pediococcus dextrinicus. Optimal culture conditions for the production of bacteriocin was attained by growing the cells in an MRS medium at a pH of 6.5~ 7.0 and a temperature of 37$^\circ$C for 36$\sim$48 hr. Solvents such as chloroform, ethanol, acetone, and acetonitrile had little effect on bacteriocin activity. However, about 50% of bacteriocin activity diminished with treatment of methanol and isopropanol at the final concentration of 50% at 25$^\circ$C for 1 hr. It was stable against a pH variation range from 3.0 and 7.0, but the activity reduced to 50% at a pH range from 9.0 to 11.0. It's activity was not affected by heat treatment at 100$^\circ$C for 30 min and 50% of activity was retained after heat treatment at 100$^\circ$C for 60 min, showing high thermostability. The bacteriocin was purified to a homogeneity through ammonium sulfate precipitation, SP-Sepharose ion-exchange chromatography, and reverse-phase high-performance liquid chromatography (HPLC). The entire purification protocol led to a 75-fold increase in specific activity and a 13.5% yield of bacteriocin activity. The molecular weight of purified bacteriocin was estimated to be about 2.5 kDa by tricine-SDS-PAGE.

Effect of Shading Methods on Growth and Fruit Quality of Paprika in Summer Season (파프리카 여름재배시 차광방법이 생육과 과실특성에 미치는 영향)

  • Ha, Jun Bong;Lim, Chae Shin;Kang, Hyo Yong;Kang, Yang Su;Hwang, Seung Jae;Mun, Hyung Su;An, Chul Geon
    • Journal of Bio-Environment Control
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    • v.21 no.4
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    • pp.419-427
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    • 2012
  • This study was carried out to investigate the effect of two shading methods, shading agent spray on the glasshouse and internal shading screen treatment, on the growth and fruit quality of paprika (Capsicum annuum L. 'Cupra' and 'Coletti') in summer season cultivation. In the shading agent treatment, a commercial shading agent diluted with water at a ratio of 1 : 4 was sprayed on the roof of a glasshouse. In the internal shading screen treatment, a 10~20% shaded screen was used during the day time when the sun radiation was greater than $700W{\cdot}m^{-2}$. Compared to the unshaded control, photosynthetic photon flux density (PPFD) decreased in the greenhouse in the shading agent (SA) and shading screen (SS) treatments by 20% and 30%, respectively. Lower air temperatures and higher relative humidities were observed in the SA than in both the control and the SS treatment. Time to reach the break point of humidity deficit $8g{\cdot}m^{-3}$ was 2 hours late in the SA than in both the control and the SS treatment. Compared to control, both the SA and the SS treatments showed lower instantaneous temperatures of leaf, fruit, and flower by $2^{\circ}C$, $5^{\circ}C$ and $3^{\circ}C$, respectively. There were no differences in number of branches, stem diameter, and leaf size among treatments although both shading treatments promoted plant height in both cultivars. Botrytis infection ratio declined with the SA treatment by 14.7% in 'Cupra' and 22.1% in 'Coletti' as compared to that in the control. Shading increased fruit size in both cultivars, whereas no differences were observed in the number of locules and thickness of fruit tissue among treatments. Shading treatment increased mean fruit weight by a range of 10 to 15 g per fruit, while it decreased soluble solids contents as compared to that in the control. Similar Hunter values were observed among treatments, while fruit firmness increased slightly in shading treatments. Compared to the control, shading treatments improved marketable fruits by 11.7~22.6% and increased the number of fruits per plant by 4~9.2 in both 'Cupra' and 'Coletti'. The results of this study indicate that shading agent application on the roof of glasshouse would be one of the most effective options to reduce heat stress imposed on the paprika crop in summer cultivation, resulting in improved crop growth and fruit yield.

Review of the Modern Values of East and West Moat Culture (동·서양 해자(垓字) 문화의 현대적 가치 재조명)

  • Jung, Yong-Jo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.1
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    • pp.25-35
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    • 2017
  • The purpose of this study is to re-exam of the modern values of a moat to utilize it with various functions such as a military defense on the outskirts of the castle, dividing the space by its boundary, controlling the micro-climate in the worsening modern environment with temperature rise due to climate change and habitat reduction of animals, and providing the habitat of animals to modern urban space, etc. The scope of the study is focusing on the castles with the moat installed to prevent the enemy from accessing directly to the wall using a pond or water path for military defense on the outskirts of the castle or to divide it into boundaries. In the Orient, the Nakan Eupseong, Haemi Eupseong, Gyeongju Wolseong in Korea and the Forbidden City in China, and Nijo Castle and Osaka Castle in Japan were selected. In the West, Edinburgh Castle in Britain, Blois Castle in France, Chillon Castle in Switzerland, and Frederiksborg Castle in Denmark were selected for the study. As a research method, literature research and field research were conducted. For the Orient, it was conducted in parallel with the literature research and field research. For the western, it was mainly conducted with literature research. For the literature research, the origin of the moat, the concept of the moat, the function of the moat, the history and culture of the western moat are based on the data from the related institutions and previous studies. For the Orient field research, exploring was conducted in two to three times from Jan. 2016 to Dec. 2016 in each of the target areas of Nakan Eupseong, Haemi Eupseong, Gyeongju Wolseong in Korea and the Forbidden City in China, and Nijo Castle and Osaka Castle in Japan. The contents of the research were analyzed through interviews, photographs, measurements, and observations on the function, size, and characteristics of the moat of each target. The results of this study are as follows. The moat was a structure installed to set a boundary for military defense facilities on the outskirts of a castle and it played an important role as a part of the city in the ancient times of Asia and the West through the Middle Ages. The role of the moat is gradually disappearing due to the disappearance of the purpose of military defense. However, moats are excluded from modern landscape planning, despite the fact that a moat filled with water is a hydrophilic space with great historical and cultural value such as various cultural activities and providing habitats for animals. By reflecting on the moats various functions in modern cities and utilizing it, it is expected to be utilized to bring pleasant air into the city where the circulation of air is blocked and energize the city as a hydroponic element.

Characteristics of Tillering as Affected by Light intensity in Dasanbyeo, an Indica/Japonica High Yielding Rice Cultivar (광도 변화에 따른 다산벼의 분얼경 발생 특성)

  • 김덕수;양원하;신진철;김제규;류점호
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.4 no.3
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    • pp.151-158
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    • 2002
  • In Korean high yielding varieties developed by crosses between indica and japonica rice, the most limiting factor for yield increase may be attributed to the less number of tillers per unit area. The goal of this study is to find out the effect of the environmental factors as well as cultivation practice on the development and increase of tillers of Dasanbyeo, the high yielding indica / japonica hybrid cultivar. The effect of temperature was examined with 3 different light intensity, 220,600, and 1220 $\mu$㏖/s/$m^2$, respectively. For all the experiments, the leading japonica variety in Korea, Hwaseongbyeo, was used fur the check cultivar for the comparison with Dasanbyeo. The increase of the tillers was more prominent in Dasanbyeo than in Hwaseongbyeo at 220 $\mu$㏖/s/$m^2$ of light intensity, while the similar increase of tiller no. was found at 600 $\mu$㏖/s/$m^2$ of light intensity treatment. However, Hwaseongbyeo showed more rapid increase of tiller at 1220 $\mu$㏖/s/$m^2$ of light intensity. The mean number of the primary tiller ranged 5 to 7 in Dasanbyeo, and 2 to 7 in Hwaseongbyeo, showing greater variation in the latter case. However, the secondary tiller number ranged from 2 to 13 for the former, and 2 to 12 for the latter. The earliest initiation of tiller node of Dasanbyeo and Hwaseongbyeo was observed on 6 and 4 days after transplanting(DAT), respectively, at 600 $\mu$㏖/s/$m^2$ of light intensity, while 10, and 7 DAT, respectively, at 1,220 $\mu$㏖/s/$m^2$. No cultivar difference was observed at 600 $\mu$㏖/s/$m^2$ with the 18 DAT. The ratio of effective tiller was lower in Dasanbyeo, ranging from 47 to 55% than in Hwaseongbyeo, ranging from 72 to 100%.

A Study on the Correlation Analysis of EEG and Vibraimage due to Auditory and Olfactory Stimulation (청각 및 후각자극에 의한 뇌파(EEG)와 진동이미지기술의 상관성 분석에 관한 연구)

  • Kim, Jung-Min;Kim, Myung-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.6
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    • pp.4291-4297
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    • 2015
  • EEG has been used to measure the emotion of amenity and discomfort in the interior space. EEG is limited to the experiment, because it is a equipment of contact type. However, Vibraimage can measure the emotion with a web camera. Because Vibraimage is a equipment of non-contact type, it is more suitable for the interior space than EEG. Therefor, it tries to find a correlation variable between EEG and Vibraimage to measure the human emotions. In this study, it were analyzed correlation of EEG and vibraimage due to variation of loudness 60[dB], 90[dB] and rosemary, jasmine scents. Check the health status of subjects who were selected 3 male students, and the period of this experiment was about months. The condition of the environmental test room was in temperature 25[$^{\circ}C$], relative humidity 50[RH%], air current speed 0.02[m/s] and illuminance 1000[lux]. It were analyzed correlation of twenty-three index of EEG(absolute ${\theta}$, relative ${\theta}$, absolute $S{\alpha}$, relative $S{\alpha}$, absolute ${\alpha}$, relative ${\alpha}$, absolute ${\beta}$, relative ${\beta}$, absolute $\gamma$, relative $\gamma$, absolute $F{\alpha}$, relative $F{\alpha}$, absolute SMR, relative SMR, $SMR/{\theta}$, $SMR+M{\beta}/{\theta}$, absolute $H{\beta}$, relative $H{\beta}$, $H{\beta}/{\alpha}$, absolute $M{\beta}$, relative $M{\beta}$, SEF50, ASEF50) and ten index of Vibraimage(Aggression, Stress, Tension/Anxiety, Suspect, Balance, Charm, Energy, Self regulation, Inhibition, Neuroticism). As a result, I was found that relative ${\gamma}$ index of EEG and neuroticism index of Vibraimage have a high correlation as (${\pm}$).414 and (${\pm}$).424.