• Journal of Nutrition and Health
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• v.20 no.2
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• pp.122-134
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• 1987

In order to investigate the effect of dietary protein and fat levels on the growth and the utilization of nitrogen and energy and body composition in rats, Sprague\ulcornerDawley 48 male rats of 8 weeks old weighing approxijIlately 215-220g were subjected to feeding trials for 8 weeks and then subsequently to metabolic trials for 2 weeks. Four dietary protein levels (4, 8, 16, 32%) and each protein level contained two fat levels(3.9, 11.7%=1O,3J% of 3600kcal ME/kg) by addition of an appropriate amount of carbo\ulcornerhydrate and the following results were obtained. The body weight gain and food efficiency ratio of the rats to which a diet of 16% protein and 3.9% fat was fed were significantly higher than in either case of 8% pro\ulcornertein diet or of 32% protein diet. The digestibility of protein in the experimental diets was 73.3 -93.4%. The digesti\ulcornerbility of energy ( energy absorption) in the experimental diets was 83.2 -91.5%. The utilization of protein and the metabolic energy efficiency in the experimental diets was highest at the diet of 8% protein and 3.9% fat. The analysis of the body composition after feeding trials for 8 weeks has shown that the content of body water and protein were not affected by protein and fat levels in diet. The content of body fat in the rats to which 3.9% fat diet was fed was high\ulcornerer than that in those to which 11.7% fat diet was fed. From the above experimental results it may be suggested that the best formula of diet for the 8 weeks old rats may be composed of the 8% protein and 3.9% fat.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.380-387
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• 2015

A lead slowing-down spectrometer (LSDS) system is a promising nondestructive assay technique that enables a quantitative measurement of the isotopic contents of major fissile isotopes in spent nuclear fuel and its pyroprocessing counterparts, such as $^{235}U$, $^{239}Pu$, $^{241}Pu$, and, potentially, minor actinides. The LSDS system currently under development at the Korea Atomic Energy Research Institute (Daejeon, Korea) is planned to utilize a high-flux ($>10^{12}n/cm^2{\cdot}s$) neutron source comprised of a high-energy (30 MeV)/high-current (~2 A) electron beam and a heavy metal target, which results in a very intense and complex radiation field for the facility, thus demanding structural shielding to guarantee the safety. Optimization of the structural shielding design was conducted using MCNPX for neutron dose rate evaluation of several representative hypothetical designs. In order to satisfy the construction cost and neutron attenuation capability of the facility, while simultaneously achieving the aimed dose rate limit (< $0.06{\mu}Sv/h$), a few shielding materials [high-density polyethylene (HDPE)eBorax, $B_4C$, and $Li_2CO_3$] were considered for the main neutron absorber layer, which is encapsulated within the double-sided concrete wall. The MCNP simulation indicated that HDPE-Borax is the most efficient among the aforementioned candidate materials, and the combined thickness of the shielding layers should exceed 100 cm to satisfy the dose limit on the outside surface of the shielding wall of the facility when limiting the thickness of the HDPE-Borax intermediate layer to below 5 cm. However, the shielding wall must include the instrumentation and installation holes for the LSDS system. The radiation leakage through the holes was substantially mitigated by adopting a zigzag-shape with concrete covers on both sides. The suggested optimized design of the shielding structure satisfies the dose rate limit and can be used for the construction of a facility in the near future.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3344-3351
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• 2021

The Rare Isotope Science Project was launched in 2011 in Korea toward constructing the Rare isotope Accelerator complex for ON line experiments (RAON). RAON will house several experimental systems, including the Muon Spin Rotation/Relaxation/Resonance (μSR) facility in High Energy Experimental Building B. This facility will use 600-MeV protons with a maximum current of 660 pμA and beam power of 400 kW. The key μSR features will facilitate projects related to condensed-matter and nuclear physics. Typical experiments require a few million surface muons fully spin-polarized opposite to their momentum for application to small samples. Here, we describe the design of a muon transport beam line for delivering the requisite muon numbers and the electromagnetic-component specifications in the μSR facility. We determine the beam-line configuration via beam-optics calculations and the transmission efficiency via single-particle tracking simulations. The electromagnet properties, including fringe field effects, are applied for each component in the calculations. The designed surface-muon beamline is 17.3 m long, consisting of 2 solenoids, 2 dipoles affording 70° deflection, 9 quadrupoles, and a Wien filter to eliminate contaminant positrons. The average incident-muon flux and spin rotation angle are estimated as 5.2 × 10⁶ μ⁺/s and 45°, respectively.

• Molecules and Cells
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• v.44 no.11
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• pp.805-829
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• 2021

CCCTC-binding factor (CTCF) critically contributes to 3D chromatin organization by determining topologically associated domain (TAD) borders. Although CTCF primarily binds at TAD borders, there also exist putative CTCF-binding sites within TADs, which are spread throughout the genome by retrotransposition. However, the detailed mechanism responsible for masking the putative CTCF-binding sites remains largely elusive. Here, we show that the ATP-dependent chromatin remodeler, chromodomain helicase DNA-binding 4 (CHD4), regulates chromatin accessibility to conceal aberrant CTCF-binding sites embedded in H3K9me3-enriched heterochromatic B2 short interspersed nuclear elements (SINEs) in mouse embryonic stem cells (mESCs). Upon CHD4 depletion, these aberrant CTCF-binding sites become accessible and aberrant CTCF recruitment occurs within TADs, resulting in disorganization of local TADs. RNA-binding intrinsically disordered domains (IDRs) of CHD4 are required to prevent this aberrant CTCF binding, and CHD4 is critical for the repression of B2 SINE transcripts. These results collectively reveal that a CHD4-mediated mechanism ensures appropriate CTCF binding and associated TAD organization in mESCs.

• Journal of Practical Agriculture & Fisheries Research
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• v.8 no.1
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• pp.43-51
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• 2006

An experiment was conducted to examine how the response of dairy cows to a change from twice to thrice-daily milking is affected by deficiencies in the dietary supplies of three amino acids, His, Met and Lys. The amino acid deficiencies were obtained by feeding the cows a diet of grass silage and a cereal-based supplement containing feather meal as the sole protein supplement. Taken overall, the results show that when cows were given the feather meal diet, even though dietary ME was in considerable excess, a deficiency of specific amino acids prevented any increase in milk yield in response to increasing the frequency of milking from twice to thrice daily. The results of half-udder milking showed that when cows consumed the diet deficient in amino acids, milking one half of the gland more frequently reduced the secretion of protein and lactose by the control gland. Neither MBF nor the ratio of 3-MH/creatinine in urine was affected by thrice-daily milking. The present results go a stage further in showing that, against a background of insufficient dietary amino acids, the stimulus of thrice-daily milking is not sufficient to induce a measurable change in the partition of amino acid use between body and udder.

• Journal of Life Science
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• v.24 no.5
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• pp.467-475
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• 2014

Sea buckthorn (Hippophae rhamnoides L.) is a well-known and rich source of biologically active compounds, such as flavonoids, carotenoids, steroids, vitamins, tannins, and oleic acid. The effects of sea buckthorn fruit extract (SBFE) on ultraviolet (UV)-induced cell death was investigated in SK-MEL-2 cells cotreated with UV and a low concentration (LoC), medium concentration (MeC), or high concentration (HiC) of SBFE. Cell viability gradually decreased in accordance with an increase in the UV dose. The cell viability of the UV+SBFE cotreated cells increased significantly compared to that of UV+vehicle-treated cells during the application of an appropriate UV radiation dose (400 mJ). In addition, the number of 4',6-diamidino-2-phenylindole (DAPI), propidium iodine (PI)-, and annexin V-stained apoptotic cells was higher in the UV+vehicle-treated cells than in the UV untreated cells. The decrease of apoptotic cell numbers varied in each treated group, but it was most significant in the SBFE-treated group. The number of PI-stained cells dramatically decreased in accordance with the concentration of SBFE, and the maximum decrease was detected in the UV+HiC-treated group. In addition, Bax expression increased and Bcl-2 expression decreased in the SBFE-treated group compared with the UV-only treated group. The level of caspase-3 remained constant in all the groups. These results suggest that SBFE may contribute to a recovery from UV-induced cell death through the regulation of apoptotic protein expression and that it may have potential therapeutic utility in ameliorating UV-induced skin ageing.

• Korean Journal of Poultry Science
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• v.31 no.4
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• pp.229-235
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• 2004

A study was conducted to examine the effect of dietary supplementation of multiple probiotics (EM) on growth performance, blood cholesterol, intestinal micro flora, and fecal gas emission in broiler chicks. A total of 450 one day old male broiler chicks (Ross $\times$ Ross) were divided into six treatments with five replications in each treatment for five weeks. Treatments were factorially designed with two levels of diet containing probiotics (DW; 0, $0.2\%$) and three levels of drinking water containing probiotics (DW; 0, 0.01, $0.1\%$). Basal diets contained $21.5\%$ CP and 3,100 kcal/kg ME for starting and $19\%$ CP and 3,100 kcal/kg ME for finishing period. Weight gain, feed intake, and feed conversions of birds fed with probiotics were not significantly different between Ds. Total cholesterol and triglyceride levels were significantly lower (P<0.05) in birds fed with DW $0.01\%$ or $0.1\%$ compared with no probiotics group, but there was no significant difference between D treatments. The number of E. coli, Salmonella and Lactobacillus in the ileum and cecum of the birds fed multiple probiotics were not significantly different from those of no probiotic groups. There were no significant differences in the $CO_2$ gas emissions of fecal between birds fed with Ds or among birds fed with DW. However, $NH_3$ gas emissions of DW $0.1\%$ were significantly lower (P<0.05) than DW $0\%$. In the results of this study, supplementation of probiotics tended to decrease the serum cholesterol and triglyceride compared to those of control groups and reduction of fecal $NH_3$ gas emission.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.1020-1024
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• 2003

Five barrows (average initial body weight 58.6 kg) were used to determine the apparent ileal digestibilities of amino acids, DM, N and energy in various soybean meal, rapeseed meal and coconut meal in finishing pigs. Dietary treatments included 1) KSBM (Korean soybean meal), 2) CSBM (Chinese soybean meal), 3) ASBM (Argentine soybean meal), 4) RSM (Rapeseed meal), and 5) CNM (Coconut meal). The diets were corn starch-based and formulated so that each protein source provided the same amount of total ME (3,490 kcal/kg), CP (15.70%), lysine (1.00%), Ca (0.80%) and P (0.60%). Protein content of the KSBM was higher than the CSBM and ASBM, with all values similar to those expected, and protein content of the CNM was lower than that of the SBM preparation and RSM. Apparent ileal digestibilities of histidine, lysine, threonine, alanine, asparatic acid, cystine, glutamic acid and serine were greater for the KSBM, CSBM, ASBM and RSM than for the CNM (p<0.05). Also, the apparent ileal digestibilities of methionine, leucine, phenylalanine, valine and tyrosine were greater for the KSBM than for the CSBM, ASBM, RSM and CNM (p<0.05). Overall, the apparent ileal digestibilities of total essential amino acids were greater for the KSBM than for the CSBM, ASBM, RSM and CNM (p<0.05), and the apparent ileal digestibilities of total non essential amino acids were greater for the KSBM, CSBM, ASBM and RSM than for the CNM (p<0.05). No difference (p>0.05) in apparent digestibility of DM at the small intestine was observed among the treatments. However, the apparent digestibility of DM at the total tract was greater for the KSBM than for the CSBM, ASBM, RSM and CNM (p<0.05). Also, apparent digestibilities of N and digestible energy at the small intestine and total tract were greater for the KSBM than for the RSM and CNM (p<0.05). In conclusion, nutrient digestibility values of SBM preparations and RSM were relatively high compared to CNM.

• Applied Biological Chemistry
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• v.9
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• pp.35-39
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• 1968

Addition of one percent cucumber, as a Kimchi component, showed the stimulation of lactic acid fermentation, by reducing the lagphase, and resulted the early matured Kimchi. Alcohol-soluble fraction from cucumber serum accerelated the growth of Lactobacillus plantarum, p-1, p-2 newly isolated strains from cucumber pickle, but had no effect on the growth rate of Streptococus faecalis. The growth promoting activity was inactivated by dialysis against water and heat treatment at $120^{\circ}C$ for 10 minutes. Softness of cucumber tissues enables to extract easily out a substance, which is thought one of the important factors for the stimulation of me growth of Lactic acid bacteria.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1991-1997
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• 2019

In this manuscript, we present a method for the direct calculation of an ambient dose equivalent (H^* (10)) for the external gamma-ray exposure with an energy range of 40 keV to 2 MeV in an electronic personal dosimeter (EPD). The designed EPD consists of a 3 × 3 ㎟ PIN diode coupled to a 3 × 3 × 3 ㎣ CsI (Tl) scintillator block. The spectrum-to-dose conversion function (G(E)) for estimating H^* (10) was calculated by applying the gradient-descent method based on the Monte-Carlo simulation. The optimal parameters for the G(E) were found and this conversion of the H^* (10) from the gamma spectra was verified by using ²⁴¹Am, ¹³⁷Cs, ²²Na, ⁵⁴Mn, and ⁶⁰Co radioisotopes. Furthermore, gamma spectra and H^* (10) were obtained for an arbitrarily mixed multiple isotope case through Monte-Carlo simulation in order to expand the verification to more general cases. The H^* (10) based on the G(E) function for the gamma spectra was then compared with H^* (10) calculated by simulation. The relative difference of H^* (10) from various single-source spectra was in the range of ±2.89%, and the relative difference of H^* (10) for a multiple isotope case was in the range of ±5.56%.