• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.136-140
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• 1985

The studies were conducted to test for combining ability and to evaluate resistance to maize dwarf mosaic virus (MDMV) by diallel crosses of corn inbreds. For the genetic analysis of the resistance, a diallel set of crosses without reciprocals was made using the eight corn inbreds which had different degrees of resistance to MDMV. Twenty eight $F_1$ hybrids showed different symtom severity. the highest value is 3.63 and the lowest value is 1.87 in disease ratings (1-4). General combining ability (GCA) for resistance to MDMV was highly significant, but specific combining ability (SCA) was not significant. Two inbreds, A632 and KS15 showed negative GCA effects, indicating that these parents were good general combiners and that resistance to MDMV increased in hybrid combinations. Hyrid A632 x KS5, showed the highest negative SCA effect and several combinations showed negative SCA effects. The analysis of parent-offspring covariance (Wr) and array variance (Vr), suggest that there may be many dominant genes in the resistant inbreds and many recessive genes in the susceptible inbreds.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.1
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• pp.14-21
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• 1993

N-Heterocyclic aromatics (NHA) are widely occurring environmental pollutants formed during the pyrolysis of nitrogen-containing organic chemicals. NAH are found in significant amounts in tobacco condensates, synthetic fuels, polluted river sediment, and effluents from the heating of coal. Following topical application 7H-dibenzo[c, g]carbazole (DBC) induces cancer in liver as well as skin, indicating that dermal exposure can lead to systemic effect. DBC and dibenz[a,j]acridine (DBA) are examples of NHA. The potency of many carcinogenic compounds is related, at least in part, to the efficiency of their biological activation. We undertook studies to determine which initial metabolites lead to the formation of high levels of carcinogen-DNA adducts in vivo. DBC and DBA's, DBA, trans-DBA-1,2-dihydrodiol (DBA-1,2-DHD), trans-DBA-3,4-dihydrodiol (DBA-3,4-DHD), and trans-DBA-5,6-dihydrodiol (DBA-5,6-DHD), were applied to the skin of mice. There were six adducts that were related to DBC application. These addusts were seen in the target organ, liver at high levels, but at very low levels in non-target organs, skin, lung and kidney. In skin, DBA produced two distinct adducts. The same two adducts were seen when DBA-3,4-DHD was applied. In addition the total adduct level elicited by DBA-3,4-DHD higher than that of parent compound. Two adducts were seen when DBA-5,6-DHD was applied, but these were very different from adducts seen with DBA. These results suggested that activation of DBA to DNA-binding compounds in skin includes initial formation of DBA-3,4-DHD.

• Journal of Applied Biological Chemistry
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• v.58 no.2
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• pp.139-143
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• 2015

In the present study, we investigated the oral toxicity of Amomum tsao-ko Crevost et Lemaire, (Zingiberaceae) extract in Balb/c mice (BALB, n=60) for 3 weeks. Balb/c mice (10 mice/group, 6 group, $20{\pm}2g$, 6 weeks) were orally administered for 21 days, with dosage of 250, 500, 1000, 2000 mg/kg/day. Ethanol extract of A. tsao-ko did not affect any significant change of mortality, clinical signs, organs and body weights. Also, there were not significantly difference from the naive group (control) in hematological and serum biochemical examination. Consequently, these findings indicate that 3-week treatment with the ethanol extract of A. tsao-ko was not any toxic effects in Balb/c mice and the no-observed adverse effect level (NOAEL) for oral toxicity was determined to be 2000 mg/kg/day under our experimental conditions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.4
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• pp.61-70
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• 1986

In accordance with a rapid growth of demani on aquatic animals, researches of the unused fishery resources On the deep sea b~d in the Korean Waters has been and will be required. The authors carried out a series of fishing experiments to investigate the available resources and to find the effective fishing method on the deep sea bed of the Korean East Sea. In the experiments, 19 kinds of traps which are different from each other in shape, mesh size and entrance diameter were used. The fishing experiments w~r;; carried out in four areas of 20Dm, 600.'11, 800m and 1000.'11 deep respectively, by the Pusan 402 (30:) GT) and the Pusan 403 (279GT), the training ships of National Fisheries University of Pusan, during August, 1986. The catc~ were analyzed with the size, the depth and the construction of traps. The results obtained can be summarized as follows: 1. Main species of the catch w~re pink shrimp, Pandalus bolelis, a kind of welks, Buccimum striatissimum and a kind of larg~ crabs. Chiono8cetes japonicus and the another species were few. 2. The CPUE value (expressed by the number of catch per trap in this paper) of pink shrimp was the highest in the depth of 20J-n around, and the value in the depth of 600.'11 or more decreased gradually with an increase of the depth. But, the value of Buccimum straitissimum was much higher in the depth of 6:J:)!1I or more than that in the depth of 200m around. On the other hand, the value of Chion:Jecetes japonjcus was very low in general. 3. The iniividual body size of the catch differed with the depth. Pink shrimps caught in the depth of 200m around were smaller than those in the depth of 600.'11 or more. In contrast with this, Baccimum striatissim:t.m caught in the depth of 200m around were larger than those in the depth of 600.'11 or more. 4. Depending on the selection curve in Ishida's method for the mesh size of trap webbing, the carapace length of pink shrimp and the shell length of Buccimum striatissimum which are equivalent to 100% relative catching efficiency can be estimated about 3.5cm and 6.5cm or so respectively. 5. The number of catch of pink shrimp and Buccimum striatissimum by the 60.'1'1.'11 entrance diameter of trap were less than that by the 90mm, 120mm and 150mm, even thogh the diffierence am~r, g 9:Jmm, 120.'11.'11 and 150:1'.'11 are not so large.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.521-534
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• 2017

In 2013 the Netflix, an OTT in USA, launched all at once 13 episodes of the House of Cards season. Binge-watching is the word which means watching continuously 2~6 episodes of a TV program with one sitting, the new normal of TV watching behavior, cultural and social currents all over the world. This study has analyzed the factors and motivations which affect to the persistent intention to use binge-watching. It conducted an online survey from 333 Quota sample from Korean age groups between 20th~60th with 81 questionnaires. The 5 groups were induced as motivation factors to binge-watching. The 3 groups which consisted of , , are affecting as positive to intention to use binge-watching. But the other 2 groups which are and doing as negative. The survey has shown that the persistent intention to binge-watching is affected by ages more younger, whom doing binge watching more frequently, whom estimating more higher to the conceived usefulness to use. As a theoretical model, expanded technology acceptance model was adopted and US drama House of Cards. This study could promote the next generation contents planning and S-VOD service industry.

• Journal of Biomedical Engineering Research
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• v.34 no.3
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• pp.129-134
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• 2013

The essential tremor is an involuntary oscillatory movement of body parts. Conventional treatments of essential tremor have little effects in some patients and also leads to significant side effects. Alternative to these treatments, sensory stimulation may have beneficial effects on the essential tremor. The purpose of this study was to analyze an effect of sensory stimulation on essential tremor. Ten patients with essential tremor ($67.4{\pm}8.82$ yrs, 5 men and 5 women) participated in this study. Three-axis gyro sensors were attached on index finger, hand and forearm of patients. Task of 'arms outstretched forward' was performed with and without sensory stimulation. Vectorsum of three dimensional angular velocities (pitch, roll, yaw) was calculated. Outcome measures included root-meansquare (RMS) mean of the vector-sum amplitude, total power, peak power and peak frequency. RMS amplitude, total power and peak power were reduced by sensory stimulation (p < 0.05). Peak frequency was not affected by sensory stimulation. The results indicate that the sensory stimulation is useful to suppress the essential tremor.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.976-982
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• 2007

This study investigated whether supplemental Cu, Fe, Zn, and Mn are needed in a practical diet for pullets. Four hundred and twenty females of an egg-laying strain (1-d-old, Lohmann Brown Layer) were randomly distributed into 4 groups, consisting of 7 replicates of 15 birds each. During the 18-week experimental period, chicks were given three basal diets in sequence, each with single or multiple Mn, Zn and Cu supplementation to improve the mineral balance gradually. In the Control, no Mn, Zn, and Cu were added; in the single Mn supplemented group (sMn) Mn was added to 120, 60, and 60 mg/kg for 1-6, 7-12, and 13-18 weeks of age, respectively; in the multiple Mn and Zn supplemented group (mMnZn), Mn was added to 180, 90, and 90 mg/kg and Zn was added to 120, 105, and 105 mg/kg for 1-6, 7-12, and 13-18 weeks of age, respectively; in the multiple Mn, Zn, Cu supplemented group (mMnZnCu), Mn, Zn, and Cu were added to the same multiple of basal Fe concentration relative to NRC (1994) recommendations. Energy and protein metabolizability were determined by subtracting energy/protein intake by energy/protein excretion (from both feces and urine) and dividing by energy/protein intake. There were no statistically significant differences between groups in terms of feed intake, final body weight or tibia length throughout the experiment. Optimal growth performance was observed in the Control, while adding trace minerals to basal diets tended to result in decreased productive performance. Protein metabolizability was increased by mMnZn and mMnZnCu treatments, but energy metabolizability was not affected. Concentrations of Mn, Zn, Cu in excreta varied greatly related to dietary content, and the retentions of Cu, Fe, Zn and Mn were all increased due to the improvement of mineral balance. Based on these results, it is suggested that the concentrations of Cu, Fe, Zn and Mn in typical basal diets used in this study were adequate for normal growth for pullets from 1 to 18 weeks of age.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.252-262
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• 2018

Objective: An experiment was conducted to evaluate dietary supplemental trace mineral source and deletion on mineral content in tissues. Methods: Weanling crossbred pigs (n = 144; 72 barrows and 72 gilts; body weight [BW] = $7.4{\pm}1.05kg$) were used. A basal diet was prepared, and trace mineral premix containing either inorganic (ITM) or organic (OTM) trace minerals (Cu, Fe, Mn, and Zn) was added to the basal diet. Pigs were blocked by sex and BW and randomly allotted to 24 pens for a total of 6 pigs per pen, and fed a diet containing either ITM or OTM supplemented at the 1998 NRC requirement estimates for each of 5 BW phases (Phase I to V) from 7 to 120 kg. The trace mineral supplementation was deleted for 6, 4, 2, and 0 wk of Phase V; regarding nutrient adequacy during this phase, the indigenous dietary Fe and Mn was sufficient, Cu was marginal and Zn was deficient. Results: At the end of Phase IV, Mn content (mg/kg on the dry matter basis) was greater (p<0.05) in heart (0.77 vs 0.68), kidney (6.32 vs 5.87), liver (9.46 vs 8.30), and longissimus dorsi (LD; 0.30 vs 0.23) of pigs fed OTM. The pigs fed OTM were greater (p<0.05) in LD Cu (2.12 vs 1.89) and Fe (21.75 vs 19.40) and metacarpal bone Zn (141.86 vs 130.05). At the end of Phase V, increased length of deletion period (from 0 to 6 wk) resulted in a decrease (linear, p<0.01) in liver Zn (196.5 to 121.8), metacarpal bone Zn (146.6 to 86.2) and an increase (linear, p<0.01) in heart Mn (0.70 to 1.08), liver Mn (7.74 to 12.96), and kidney Mn (5.58 to 7.56). The only mineral source by deletion period interaction (p<0.05) was observed in LD Zn. Conclusion: The results demonstrated differential effects of mineral deletion on tissue mineral content depending on both mineral assessed and source of the mineral.

• Korean Journal of Applied Biomechanics
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• v.16 no.3
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• pp.137-148
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• 2006

The purpose of this study was to compare muscle activity in the lower extremity during walking wearing jogging and roller shoes. Twelve male middle school students (age: 15.0 yrs, height 173.7 cm, weight 587.7 N) who have no known musculoskeletal disorders were recruited as the subjects. Seven pairs of surface electrodes (QEMG8, Laxtha Korea, gain = 1,000, input impedance >$1012{\Omega}$, CMMR >100 dB) were attached to the right-hand side of the body to monitor the rectus femoris (RF), vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), and medial (GM) and lateral gastrocnemius (GL) while subjects walked wearing roller and jogging shoes in random order at a speed of 1.1 m/s. An event sync unit with a bright LED light was used to synchronize the video and EMG recordings. EMG data were filtered using a 10 Hz to 350 Hz Butterworth band-passdigital filter and further normalized to the respective maximum voluntary isometric contraction EMG levels. For each trial being analyzed, five critical instants and four phases were identified from the recording. Averaged IEMG and peak IEMG were determined for each trial. For each dependent variable, paired t-test was performed to test if significant difference existed between shoe conditions (p<.05). The VM, TA, BF, and GM activities during the initial double limb stance and the initial single limb stance reduced significantly when going from jogging shoe to roller shoe condition. The decrease in EMG levels in those muscles indicated that the subjects locked the ankle and knee joints in an awkward fashion to compensate for the imbalance. Muscle activity in the GM for the roller shoe condition was significantly greater than the corresponding value for the jogging shoe condition during the terminal double limb stance and the terminal single limb stance. Because the subjects tried to keep their upper body weight in front of the hip to prevent falling backward, the GM activity for the roller shoe condition increased. It seems that there are differences in muscle activity between roller shoe and jogging shoe conditions. The differences in EMG pattern may be caused primarily by the altered position of ankle, knee, and center of mass throughout the walking cycle. Future studies should examine joint kinematics during walking with roller shoes.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.44-52
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• 1996

Humic substances of 17 organic fertilizers available on the market were the objects of study. The list of ingredients for formulation of them comprised fish meal. bone meal, oil-cakes, brewer's grains, peat, sawdust, wood bark, zeolite, soil conditioner, live-stock droppings, amino acid fermentation byproduct, chaff, limestone and others. Humic and fulvic acids were isolated from those substances and given chemical and spectroscopic analyses. Nutritional values of the organic fertilizers showed big diversity. Humification of organic matter was incomplete for some of the fertilizers as indicated by a high C/N ratio. Extractable humic acid percentage was higher, in general, than that of fulvic acid. Also the relative content of humin increased with advanced humification. Total acidity was closely related to phenolic hydroxyl groups. Relationships between carboxyl and hydroxyl groups. and carboxyl and alcoholic hydroxyl groups were very significant. Ultraviolet and visible light absorption spectra of humic and fulvic acids were substantially similar. The types of humic acids were B. P, and Rp. Two humic acids of the 17 samples belonged to B type. 3 to P type and all the rest to Rp type.