• Journal of Aquaculture
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• v.21 no.2
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• pp.76-81
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• 2008

We investigated the food-effect for ultra-small rotifer Synchaeta kitina cultured under a individual and community by several diets: 3 single trials(Tetraselmis suecica, TET; Isochrysis galbana, ISO; Marine Chlorella ellipsoidea, CHL) and 3 trials with a mixture of 2 species. The rotifer was cultured on the different feeding concentrations. In the individual cultures, the maximum number of offsprings and maximum lifespan of the female investigated to 5.8 inds. and 12.7 days in TET trial, respectively. Values of the developmental phases of the rotifer fed with T. suecica were higher than those of trials without T. suecica. Also it approached faster to maturation level. In the community cultures, the maximum density of TET+CHL trial elevated up to 1,569 inds./mL. But, CHL and ISO showed a poor growth rate and maximum density. The offsprings of the female increased continuously when fed by T. suecica trial, up to $10{\times}10^3$ cells/ind./day. As the quantity of supplied diet was lowered their lifespan were decreased. But, the maximum density and growth rate in the community cultures showed the highest value in the $10{\times}10^3$ cells/ind./day. The efficient food for mass culture of S. kitina was T. suecica, and optimum concentration of their food was 10,000 cells for an individual.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.12 s.103
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• pp.1179-1185
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• 2005

In this paper, novel internal antenna with its controllable resonant frequency is presented for triple-band or over mobile handsets. The operating range can include GSM(880${\~}$960 MHz), GPS(1,575$\pm$10 MHz), DCS(1,710${\~}$1,880 MHz), US-PCS(1,850${\~}$l,990 MHz), and W-CDMA(1,920${\~}$2,170 MHz). The proposed antenna is realized by combination of a half wavelength loaded line and a shorted monopole. A single shorting and feeding points are used and they are common to both antenna structures. By controlling a value of lumped inductance element between shorting point and ground plane, the antenna provides enough bandwidth to cover DCS, US-PCS, and W-CDMA respectively. When these higher bands are controlled by the values of inductance, resonant characteristics in GSM and GPS bands are maintained. In this work, maximum value of the inductor is limited within 3.3 nH to mitigate gain degradation from frequency tuning. As a result, measured maximum gain of antenna is -0.58${\~}$-0.30 dBi in the GSM band, -0.57${\~}$0.43 dBi in the GPS band and 0.38${\~}$1.15 dBi in the DCS/US-PCS/W-CDMA band. In higher band, the proposed antenna is certified that resonant frequency of about 240 MHz can be effectively controlled within gain variation of about 0.77 dB by simulation and measurement.

• Journal of Life Science
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• v.27 no.6
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• pp.694-701
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• 2017

Mycoplasma genitalium represents the smallest genome among mono-cultivable prokaryotes. To discover and compare the orthologs (conservative genes) among M. genitalium and 14 prokaryotes that are uncultivable and have less orthologs than M. genitalium, COG (clusters of orthologous groups of protein) analyses were applied. The analyzed prokaryotes were M. genitalium, one hyperthermophilic exosymbiotic archaeon Nanoarchaeum equitans, four intracellular plant pathogenic eubacteria of Candidatus Phytoplasma genus, and nine endosymbiotic eubacteria of phloem- and xylem-feeding insects. Among 367 orthologs of M. genitalium, 284 orthologs were conservative between M. genitalium and at least one other prokaryote. All 15 prokaryotes commonly have 29 orthologs, representing the significance of proteins in life. They belong to 25 translation-related, including 22 ribosomal proteins, 3 subunits of RNA polymerase, and 1 protein-folding-related. Among the 15 prokaryotes, 40 orthologs were only found in all four Candidatus Phytoplasma. The other nine Candidatus, all endosymbionts with insects, showed only a single common COG0539 (ribosomal protein S1), representing the diversity of orthologs among them. These results might provide clues to understand conservative genes in uncultivable prokaryotes, and may be helpful in industrial areas, such as handling prokaryotes producing amino acids and antibiotics, and as precursors of organic synthesis.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.11
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• pp.1755-1762
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• 2020

Objective: Thyroid hormone responsive spot 14 alpha (THRSP) has been used to investigate the regulation of de novo lipogenesis because the variation of THRSP mRNA content in the tissue affects directly the ability of that tissue to synthetize lipids. Also, this gene responds to thyroid hormone stimulation and high level of carbohydrate feeding or insulin-injection. This study was carried out to investigate variations within THRSP and their effects on body and carcass weights in Korean native chicken (KNC). Methods: A total of 585 chickens which represent the five lines of KNC (Black, Gray-Brown, Red-Brown, White, and Yellow-Brown) were reared and body weight data were recorded every two weeks from hatch until 20 weeks of age. Polymerase chain reaction- restriction fragment length polymorphism, DNA chips for Agilent 2100 Bioanalyzer, and Fluidigm Genotyping Technology, were applied to genotype selected markers. A linear mixed-effect model was used to access association between these single nucleotide polymorphism (SNP) markers and growth-related traits. Results: A total of 30 polymorphisms were investigated in THRSP. Of these, nine SNPs for loci were selected to perform association analyses. Significant associations were detected between g.-49G>T SNP with body weight at 20 weeks of age (BW20), g.451T>C SNP with growth at 10 to 12 weeks of age (GR10-12), and g.1432A>C SNP with growth at 14 to 16 weeks trait (GR14-16) and body weight at 18 weeks of age (BW18). Moreover, diplotype of the THRSP gene significantly affected body weight at 12 weeks of age (BW12) and GR10-12 traits. Diplotype of ht1/ht2 was favorable for BW12 and GR10-12 traits. Conclusion: These results suggest that THRSP can be regarded as a candidate gene for growth traits in KNC.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.7
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• pp.923-930
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• 2009

This study was conducted to compare three models: two random regression models with and without considering heterogeneity in the residual variances and a lactation model (LM) for evaluating the genetic ability of Holstein cows in Korea. Two datasets were prepared for this study. To apply the test-day random regression model, 94,390 test-day records were prepared from 15,263 cows. The second data set consisted of 14,704 lactation records covering milk production over 305 days. Raw milk yield and composition data were collected from 1998 to 2002 by the National Agricultural Cooperative Federation' dairy cattle improvement center by way of its milk testing program, which is nationally based. The pedigree information for this analysis was collected by the Korean Animal Improvement Association. The random regression models (RRMs) are single-trait animal models that consider each lactation record as an independent trait. Estimates of covariance were assumed to be different ones. In order to consider heterogeneity of residual variance in the analysis, test-days were classified into 29 classes. By considering heterogeneity of residual variance, variation for lactation performance in the early lactation classes was higher than during the middle classes and variance was lower in the late lactation classes than in the other two classes. This may be due to feeding management system and physiological properties of Holstein cows in Korea. Over classes e6 to e26 (covering 61 to 270 DIM), there was little change in residual variance, suggesting that a model with homogeneity of variance be used restricting the data to these days only. Estimates of heritability for milk yield ranged from 0.154 to 0.455, for which the estimates were variable depending on different lactation periods. Most of the heritabilities for milk yield using the RRM were higher than in the lactation model, and the estimate of genetic variance of milk yield was lower in the late lactation period than in the early or middle periods.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.10
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• pp.1446-1458
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• 2013

The study assessed the effect of dietary supplementation of leaf meal mixture (LMM) containing condensed tannins (CT) on feed intake, nutrient utilization and performance of sheep infected with Haemonchus contortus. Eighteen adult sheep of similar age and body weight ($25.03{\pm}1.52$) were included in this study and out of these, 12 sheep were infected with single dose of infective third stage larvae of H. contortus at 2,000 larvae per sheep. The experimental sheep were allocated in three different groups' i.e. negative control (NC; no infection), control (C; H. contortus infected) and treatment (T; H. contortus infected+CT at 1.5% of the DM through LMM) and the experiment was conducted for a period of 90 d. The intake of dry matter (DM), organic matter (OM) and digestibility of DM, OM, neutral detergent fibre (NDF) and acid detergent fibre (ADF) were comparable among three animal groups. However, digestibility of crude protein (CP) and ether extract (EE) were significantly (p<0.05) higher in NC group as compared to both C and T groups. Nitrogen (N) retention (g/d or % of N intake) was significantly (p = 0.038) lower in C group as compared to T and NC groups. Daily intake (g/kg $W^{0.75}$) of digestible crude protein (DCP), digestible organic matter (DOM) and total digestible nutrient (TDN) did not differ significantly (p<0.05) in the three groups. Haemoglobin (Hb) and packed cell volume (PCV) were significantly (p<0.001) higher in treatment group as compared to control. The level of Hb and PCV reduced (p<0.001) after 30 days of experimental feeding. CT significantly (p<0.001) reduced serum urea in T group as compared to NC and C groups. Serum proteins differed significantly (p<0.01) among the three groups. The activity of serum enzymes AST, ALT, ALP and LDH were also statistically non significant (p<0.05) among treatments. The weight of abomasal lymph nodes (ALN) in T group was higher (p<0.05) than in C group. Treatment group had lower (p<0.05) total worms and fecal egg count compared to control group. It may be concluded that dietary supplementation of CT through LMM significantly improved the N retention, and inhibited the different developmental stages of Haemonchus contortus in experimental sheep.

• Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.10.1-10.8
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• 2018

Substitution effect of white radish' by-product (WRB) and tunic of sea squirt (TSS) for Undaria in feed on growth and carcass composition of abalone was determined. Eight-hundred forty juveniles were distributed into 12 containers. Three formulated diets were prepared in triplicate. A 15% Undaria was included in the control diet. The 15% Undaria was substituted with a same amount of WRB and TSS, referred to as the DRG and TSS diets, respectively. Finally, dry Undaria was also prepared to compare effect of the formulated diets on performance of abalone. The experimental diets were fed to abalone once a day at a satiation level with a little leftover. The feeding trial lasted for 16 weeks. Crude protein, crude lipid, and ash content of the experimental diets changed over all period of time. Higher crude protein and lipid and ash contents retained in all formulated diets compared to the Undaria were observed at 24 and 48 h after seawater immersion. Survival of abalone was not affected by the experimental diets. Weight gain and specific growth rate (SGR) of abalone fed the TSS diet was greater than all other diets. Weight gain and SGR of abalone fed the control diet was not different from those of abalone fed the WRB diet. Proximates of the soft body of abalone was affected by the diets. In conclusion, WRB and TSS are the promising feed ingredients to replace Undaria in abalone feed; especially, TSS is superior to either Undaria or WRB. The formulated diets produced improved growth performance of abalone over the single Undaria.

• Journal of Aquaculture
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• v.22 no.1
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• pp.68-73
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• 2009

Yeast has been widely used as a food organism for mass culture of rotifer and also considered as a partial substitute food for microalga in shellfish culture. But the dietary value of yeast is poorer than that of microalga due to its low nutrition and thick cell wall. This study was carried out to find a nutritious yeast species as a food organism and to investigate the nutritional value of manipulated yeast for shellfish. First of all, three species of yeast (Saccharomyces cerevisiae, Candida utilis, Kluyveromyces fragilis) and their manipulated yeast were tested on the survival (%) and growth of Artemia nauplii and Mytilus edulis larvae, which were representative filter feeding animal and easy to control. The survival (%) and growth of Artemia nauplii fed C. utilis were higher than those fed S. cerevisiae or K. fragilis. The growth of Artemia nauplii and M. edulis larvae, which were fed manipulated yeast was higher than that fed non-manipulated one. The manipulated yeast with higher removal rate of cell wall showed better dietary value for Artemia nauplii and M. edulis larvae. M. edulis larvae fed mixed-diet with Isochrysis galbana (50%) and manipulated C. utilis (50%) showed significantly higher growth than those fed single-diet with I. galbana. It means that manipulated C. utilis can substitute I. galbana at least 50% for M. edulis larvae.

• Journal of the Korea Society of Computer and Information
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• v.15 no.8
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• pp.59-66
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• 2010

In this paper, the internal antenna for mobile communication handset which is able to control both coupling coefficient and resonant frequency without any major modification of radiator and ground plane of antenna. Novel internal antenna with its controllable resonant frequency is presented for triple-band or over mobile handsets. The operating range can include GSM(880~960 MHz), GPS($1,575{\pm}10MHz$), DCS(1,710~1,880MHz), US-PCS(1,850~1,990 MHz), and W-CDMA(1,920~2,170 MHz). The proposed antenna is realized by combination of a half wavelength loaded line antenna and PIFA(Planner Inverted F Antenna). A single shorting and feeding points are used and they are common to both antenna structures. One of two inductors which is placed at each shorting post, one inductor is for adjusts amount of coupling, and the other controlling the resonant frequency in DCS/US-PCS/WCDMA bands. The inductance range for control of input impedance is between 0nH and 6.8nH, and each of gain variation in GSM, GPS and DCS/US-PCS/WCDMA band is under 0.15dBi, 0.73dBi and 0.29dBi. The inductance range for control of the resonant frequency is between 1640MHz and 2500MHz, and each of gain variation in GSM, GPS and DCS/US-PCS/WCDMA band is under 0.46dBi, 0.53dBi and 0.8dBi.

• Korean Journal of Poultry Science
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• v.17 no.2
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• pp.101-107
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• 1990

Apparent and true metabolizable energy (AME and TME) contents and true amino acid availability (TAAA) values of full-fat seed, oil meal and oil of canola were assayed employing mature Single Comb white Leghorn roosters. For AME, test diets containing 30% level of canola full-fat seed, oil meal, oil meal plus oil or 10% level of oil were fed for a 3-day adaptation period, followed by a 4-day fecal collection period. For TME and TAAA, 30g test diets were force-fed and total excreta were collected for 48 hours, following a 24 hour fasting period. Metabolizable energy values were corrected to zero nitrogen balance(AMEn and TMEn), Canola contained 4,485, 1,984,8,275 and 5,655kcal/kg of AMEn and 4,577, 2,103, 8,487 and 5,630kcal/kg of TMEn for full-fat seed, oil meal, oil and mixture of meal plus oil, respectirely. The mixtures of oil meal plus oil had significantly higher available energy contents than the full-fat seeds (p＜0.01) . In general, TAAA values of full-fat seed were higher than those of oil meal.