• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.701-707
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• 2012

Immune stress is the loss of immune homeostasis caused by external forces. The purpose of this experiment was to investigate the effects of immune stress on the growth performance, small intestinal enzymes and peristalsis rate, and mRNA expression of nutrient transporters in broiler chickens. Four hundred and thirty-two 1-d-old broilers (Cobb500) were randomly assigned to four groups for treatment; each group included nine cages with 12 birds per cage. Group 1 = no vaccine (NV); Group 2 = conventional vaccine (CV); group 3 = lipopolysaccharide (LPS)+conventional vaccine (LPS); group 4 = cyclophosphamide (CYP)+conventional vaccine (CYP). The results demonstrated that immune stress by LPS and CYP reduced body weight gain (BWG), feed intake (FI), small intestine peristalsis rate and sIgA content in small intestinal digesta (p<0.05). However, the feed conversion ratio (FCR) remained unchanged during the feeding period. LPS and CYP increased intestinal enzyme activity, relative expression of SGLT-1, CaBP-D28k and L-FABP mRNAs (p<0.05). LPS and CYP injection had a negative effect on the growth performance of healthy broiler chickens. The present study demonstrated that NV and CV could improve growth performance while enzyme activity in small intestine and relative expression of nutrient transporter mRNA of NV and CV were decreased in the conditions of a controlled rational feeding environment. It is generally recommended that broilers only need to be vaccinated for the diseases to which they might be exposed.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.409-413
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• 2008

A simple method for the purification of porphyran from laver Porphyra yezoensis was developed to obtain information for the development of food materials with biological functionality. Crude porphyran (CP) was extracted from dried laver in boiling water for 3 h, and then fractionated using cetylpyridinium chloride into an acidic fraction (CP-F1) and a neutral fraction (CP-F2). CP-F1 was fractionated further by fractional ethanol precipitation. Fraction CP-F1-70, precipitated at an ethanol concentration of 61-70% was the major fraction containing 68.1% of the yield from the initial fraction CP-F1. The CP-F1-70 fraction displayed a single band on Sepharose CL-4B with a molecular mass of 550 kDa, indicating a homogeneous polysaccharide. The molar ratio of galactose, 3,6-anhydro-L-galactose, 6-0-methyl-D-galactose and ester sulfate of CP-F1-70 was 1:0.32:0.07:0.53. This method is very useful for rapid and large-scale preparation of purified porphyran because it is compatible with mass production.

• Neonatal Medicine
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• v.15 no.1
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• pp.38-43
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• 2008

Purpose : The purpose of this study was to evaluate the relationship between cord serum adiponectin (APN) and IGF-I concentrations and fetal growth. Methods : Umbilical cord serum APN and IGF-I concentrations were measured in healthy term singleton deliveries (n=72). The association of cord serum APN and IGF-I concentrations was evaluated in relation to birth weight, height, head circumference, gender, ponderal index, placental weight, feto-placental (F/P) weight ratio, maternal weight gain, and maternal body mass index (BMI). Results : The mean cord serum APN was 29.2${\pm}$10.46 $\mu$g/mL. The cord serum APN and birth weight demonstrated a bell-shape relationship. The cord serum APN concentration was higher in females than males (P=0.001). The cord serum APN was negatively correlated with maternal BMI (r=-0.301, P=0.027), but the mean cord serum APN concentration was not correlated with birth height, birth head circumference, ponderal index, placental weight, F/P ratio, or maternal weight gain. The mean cord serum concentrations of IGF-I was 51.26${\pm}$21.54 ng/mL. The cord serum IGF-I concentration was positively correlated with birth weight (r=0.312, P=0.009), but not birth height, ponderal index, placental weight, F/P weight ratio, or maternal BMI. Conclusion : APN demonstrated a bell-shaped relationship with birth weight in healthy term infants. IGF-I was highly correlated with fetal growth, especially birth weight.

• Bulletin of the Society of Naval Architects of Korea
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• v.12 no.2
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• pp.43-58
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• 1975

There are many reports on fatigue crack of metallic materials but most of them relate crack propagation rate to stress intensity factor. The problem of crack propagation is not yet clarified, especially the bridge between micro and macro phenomena In this experiment rotating bending fatigue tests have been carried out with smoothed specimen of rolled steel plates including 0.2% carbon under application of three stress conditions to investigate the slip band and the crack propagation behaviour. The results obtained are as follows; 1) The length of cracks which have grown at initial crack tips can be expressed as follows; $l=Ae^{BNr}$(A,B: constant, $N_r$: cycle ratio) $\frac{dl}{dN}=\frac{AB}{N_f}{\cdot}e^{BNr}$($N_f$:fatigue life) 2) The ratio of slipped grain number to total grain number is $S_f=7{\sigma}-5.6$-5.6{\sigma}_c$($\sigma$: stress amplitude) (${\sigma}_c$: fatigue limit) 3) When the fatigue process transfers from Stage I to Stage II, the crack which propagates into specimen changes its direction from that of the maximum shear stress to the direction of perpendicular to principal stress and this is same in the circumferential direction of specimen. the crack propagation behaviors of both sides of a crack are different each other when they approach to the grain boundary.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.9
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• pp.469-475
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• 2016

The study is the result of an practical operation analysis for the full scale fishery product wastewater treatment plant with immersed MBR (iMBR) process. Since fishery product industries show a wide range of wastewater generation by the season, design and operation of the equalization basin are very important factor. The aeration system for the equalization basin mixing can save the chemical consumption for followed system through the restriction of acid fermentation. The concentrations of wastewater primary DAF process treated were BOD 2,291 mg/L, $COD_{Mn}$ 530 mg/L, SS 256.8 mg/L, T-N 38 mg/L, T-P 13.5 mg/L respectively. It was considered that iMBR is the most efficient biological process for high salinity content wastewater since It is irrelevant to the capability of the sludge precipitation. SADp and SADm were 0.31, $26.5m^3/hr{\cdot}m^3$ respectively. In iMBR process, the critical F/M ratio was derived at 0.08~0.10 gBOD/gMLSS by analysing the correlations between MLSS, normalized TMP and temperature. The effluent concentrations were BOD 1.8 mg/L, $COD_{Mn}$ 12.4 mg/L, SS 1.0 mg/L, T-N 7.85 mg/L, T-P 0.1 mg/L and removal efficiencies were 99.9%, 97.6%, 96.3%, 95.7%, 97.8% respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.1
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• pp.75-78
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• 2005

Inheritance of cocoon and shell weight characters in silkworm crosses between sex-limited at larva stage lines, including three (NIG$_{1}$ $\times$ TV$_{3/2}$ ,NIG$_{1}$ $\times$ TBV$_{2/24}$ and NIG$_{1}$ $\times$ B$_{2/6}$ ) from Japanese type and three (NIG$_{2}$ $\times$ B$_{2/6}$ ,TV$_{3/2}$ $\times$ NIG$_{1}$ and NIG$_{2}$ $\times$ TBV$_{2/24}$ ) from Chinese type was studied at Regional Centre for Scientific­Applied Service - Vratza during the period of 2000 ­2002. Inheritance of tested characters in F I was deter­mined through genetic parameters, additiveness (a), dominance (d) and their ratio (d/a). Degree and frequency of transgressions in F$_{2}$ were calculated also. Over dominance (d/a(>) 1) with bigger contribution of the parent with higher value was determined at inheritance tested characters. Transgressions obtained at cocoon and shell weight characters were positive and varied in wide limits. The productivity of parent's lines had defined the variability of genetic parameters for degree and frequency of transgressions. Combination of positive transgressions at cocoon and shell weight characters in F2 hybrid populations from sex-limited at larva stage allow us to select individuals with high productive potential for further use in selection programs.

• ALGAE
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• v.18 no.4
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• pp.255-262
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• 2003

Ecological characteristics of phytoplankton communities were investigated biweekly at 6 stations from Feb. 2001 to Feb. 2002 at the lower part of the Han River. During the study, a total of 267 taxa which were composed of 114 green algae, 104 diatoms, 22 blue-green algae, 13 chrysophytes and 2 dinoflagellates were observed. The standing crops of phytoplankton communities were ranged from 1.30 ${\times}10^6$ cells ${\cdot}l^{-1}$ to 37.47 ${\times}10^6$ cells ${\cdot}l^{-1}$. The dominant species were 11 taxa including Pediastrum duplex, Scenedesmus quadricauda in green algae, Osillatoria limosa, Microcystis aeruginosa, Merisomorpedia sp., Phormidium sp. in blue-green algae, and Asterionella gracillima, Aulacoseira granulata, Fragilaria crotonensis, Stephanodiscus hantzschii f. tenuis, Synedra acus in diatoms. Asterionella gracillima and Stephanodiscus hantzschii f. tenuis were abundant at every station from winter to spring. Stephanodiscus hantzschii f. tenuis occupied the highest dominant ratio and standing crop. From summer to autumn, dominant species were Aulacoseira granulata at all stations and blue-green algae such as Osillatoria limosa, Microcystis aeruginosa, Merisomorpedia sp. at some stations. These 4 species were mostly present at the lower stations 4, 5, 6 and very few at the upper stations 1, 2, 3.

• Coupled systems mechanics
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• v.8 no.4
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• pp.351-375
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• 2019

The present work investigates the use of a rigid rocking block as a tool to reduce vibrations in a frame structure. The study is based on a simplified model composed by a 2-DOF linear system, meant to represent a general M-DOF frame structure, coupled with a rocking rigid block through a linear visco-elastic device, which connects only the lower part of the 2-DOF system. The possibility to restrain the block directly to the ground, by means of a second visco-elastic device, is investigated as well. The dynamic response of the model under an harmonic base excitation is then analysed in order to evaluate the effectiveness of the coupling in reducing the displacements and the drift of the 2-DOF system. The nonlinear equations of motion of the coupled assemblage 2-DOF-block are obtained by a Lagrangian approach and then numerically integrated considering some reference mechanical and geometrical quantities as variable parameters. It follows an extensive parametric analysis, whose results are summarized through behaviour maps, which portray the ratio between the maximum displacements and drifts of the system, with and without the coupling with the rigid block, for several combinations of system's parameters. When the ratio of the displacements is less than unity, the coupling is considered effective. Results show that the presence of the rocking rigid block improves the dynamics of the system in large ranges of the characterizing parameters.

• Journal of the Korean Society of Physical Medicine
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• v.17 no.1
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• pp.127-137
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• 2022

PURPOSE: This study sought to evaluate muscle activity and foot pressure during gait, and balance in female college students with genu valgum. METHOD: Participants were assigned based on their Q-angle to genu valgum group greater than 20° (GVG, n = 12), unilateral genu valgum group greater than 20° (UVG, n = 11), and control group (CON, n = 13). All subjects were evaluated for balance (Trace length, C90 area, C90 angle, and the Romberg test), muscle activity (gluteus medius; GM, tensor fasciae latae; TFL, vastus medialis; VM, vastus lateralis; VL, biceps femoris; BF, gastrocnemius; GCM and tibialis anterior; TA) and foot pressure (F/F ratio, R/F ratio, Hallux, 2~5 toe, 1st MT, 2~4 MT, 5th MT, Midfoot, M/heel, and L/heel) during gait. RESULTS: Romberg test showed significantly increased loss of balance in the UVG group compared with the CON. In the forward position, the imbalance was significantly increased in the UVG and GVG groups compared to the CON. Muscle activity of VL, GCM, and TA significantly increased in the GVG group compared with the CON. Static foot pressure, 1st MT significantly increased in the GVG compared to the CON group. The 5th MT significantly decreased in the CON compared with the GVG group. The R/F ratio significantly decreased in the GVG compared to the CON group. In dynamic foot pressure, the 2~5 toe significantly increased in the GVG compared with the UVG group. The left 5th MT significantly decreased in the UVG compared with the CON and GVG groups. CONCLUSION: These results indicate that genu valgum has a negative effect on balance, muscle activity, and foot pressure during gait in female college students.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.245-250
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• 1999

Plantlets derived from leaf blade-segment culture of a variegated tobacco (Nicotiana tabacum L. cv. BY-4) that was induced by a heavy-ion ($^{14}N$) beam irradiation to proembryos, were characterized. When explants from both white and green sections of leaves of the variegated plant were cultured on MS medium containing 0.1 mg/L NAA and 1.0 mg/L BAP, the white sections yielded only white shoots, whereas the green sections generated approximately 47.2% green, 37.4% white and 15.4% variegated shoots. In the F1 generation of a green tobacco derived from the leaf blade-segment culture, the segregation ratio of green to white was 1,651:54. Furthermore, reciprocal crosses showed that all of the progenies was green, indicating that the variegation is not maternally inherited. When the signal intensity of photosynthesis genes was determined by DNA gel blot analysis using the variegated leaves derived from green sections of variegated leaves, there were more of the rbcL, psbA, 16S rDNA and 23S rDNA chloroplast genes in the white sections than the chloroplast genes in wild type and green sections of the variegated plants.