γ-aminobutyric acid (GABA) is a natural stress-reducing substance and is actively used as a human health supplement. However, minimal research has been conducted on its use in cattle. This study was conducted to evaluate the effects of GABA on the growth performance, complete blood count, blood metabolites, and carcass characteristics of fattening Hanwoo steers. Twenty-one fattening steers were randomly assigned to one of three treatments: control (basal diet: concentrate feed + rice straw), T1 (basal diet + GABA supplement at 0.8% of feed/head/day), and T2 (basal diet + GABA supplement at 1.6% of feed/head/day). Feed intake and conversion ratio did not differ among the treatments. However, the average daily gain during the early fattening period increased linearly to 0.80 kg, 0.86 kg, and 0.92 kg in the control, T1, and T2 groups (p<0.05). Plasma γ-glutamyl transferase (37.5, 58.2, 42.8 U/ℓ) and creatinine (1.32, 1.34, 1.49 ㎎/㎗) levels in the GABA supplement group were increased compared to those in the control group. The carcass weight (422.7, 427.1, 454.1 kg), rib eye area (86.67, 92.57, 91.14 cm2), and marbling score (3.67, 4.29, 4.14) were numerically higher in the GABA supplement group than in the control group. Thus, GABA supplementation positively affected the average daily gain and carcass characteristics of Hanwoo steers. However, the effect of the GABA supplement level of GABA was small, and further research using rumen-protected coating technology on GABA is necessary.

To address the pressing societal concern in Korea, characterized by the imminent saturation of spent nuclear fuel storage, this study was undertaken to validate the fundamental reprocessing process capable of substantially mitigating the accumulation of spent nuclear fuel. Reprocessing is divided into dry processing (pyro-processing) and wet reprocessing (PUREX). Within this context, the primary focus of this research is to elucidate the foundational principles of PUREX (Plutonium Uranium Redox Extraction). Specifically, the central objective is to elucidate the interaction between uranium (U) and plutonium (Pu) utilizing an organic phase consisting of tributyl phosphate (TBP) and dodecane. The objective was to comprehensively understand the role of HNO3 in the PUREX (Plutonium Uranium Redox Extraction) process by subjecting organic phases mixed with TBPdodecane to various HNO3 concentrations (0.1 M, 1.0 M, 5.0 M). Subsequently, the introduction of Strontium (Sr-85) and Europium (Eu-152) stock solutions was carried out to simulate the presence of fission products typically contented in the spent nuclear fuel. When the operation proceeds, the complex structure takes the following form. 􀜷􀜱􀬶 􀬶􀬾(􀜽􀝍) + 2􀜰􀜱􀬷 􀬿(􀜽􀝍) + 2􀜶􀜤􀜲(􀝋􀝎􀝃) ↔ 􀜷􀜱􀬶(􀜰􀜱􀬷)􀬶 ∙ 2􀜶􀜤􀜲(􀝋􀝎􀝃) Subsequently, separate samples were gathered from both the organic and aqueous phases for the quantification of gamma-rays and alpha particles. Alpha particle measurements were conducted utilizing the Liquid Scintillation Counter (LSC) system, while gamma-ray measurements were carried out using the High-Purity Germanium Detector (HPGe). The distribution ratio for U, Eu (Eu-152), and Sr (Sr-84) was ascertained by quantifying their activity through LSC and HPGe. Through the experiments conducted within this program, we have gained a comprehensive understanding of the selective solvent extraction of actinides. Specifically, uranium has been effectively separated from the aqueous phase into the organic phase using a combination of tributyl phosphate (TBP) and dodecane. Subsequently, samples containing U(VI), Eu(III), and Sr(II) underwent thorough analysis utilizing LSC and HPGe detectors. Our radiation measurements have firmly established that the concentration of nitric acid enhances the selective separation of uranium within the process.

This study used optical and scanning electron microscopy to analyze the surface oxidation phenomenon that accompanies a γ'-precipitate free zone in a directional solidified CM247LC high temperature creep specimen. Surface oxidation occurs on nickel-based superalloy gas turbine blades due to high temperature during use. Among the superalloy components, Al and Cr are greatly affected by diffusion and movement, and Al is a major component of the surface oxidation products. This out-diffusion of Al was accompanied by γ' (Ni3Al) deficiency in the matrix, and formed a γ'-precipitate free zone at the boundary of the surface oxide layer. Among the components of CM247LC, Cr and Al related to surface oxidation consist of 8 % and 5.6 %, respectively. When Al, the main component of the γ' precipitation phase, diffused out to the surface, a high content of Cr was observed in these PFZs. This is because the PFZ is made of a high Cr γ phase. Surface oxidation of DS CM247LC was observed in high temperature creep specimens, and γ'-rafting occurred due to stress applied to the creep specimens. However, the stress states applied to the grip and gauge length of the creep specimen were different, and accordingly, different γ'-rafting patterns were observed. Such surface oxidation and PFZ and γ'-rafting are shown to affect CM247LC creep lifetime. Mapping the microstructure and composition of major components such as Al and Cr and their role in surface oxidation, revealed in this study, will be utilized in the development of alloys to improve creep life.

An elevated temperature is expected at the deep geological repository (DGR) due to the decay heat from spent nuclear fuel and the positive geothermal gradient. The resulting elevated temperature would change the aqueous speciation and surface complexation of uranium, which is the major component in spent nuclear fuel. Since sorption reactions of uranium species on natural minerals determine the extent of uranium retardation, in this work the temperature-dependent adsorption of hexavalent uranium, U(VI), was studied by choosing alumina as the basic component mineral for complex aluminosilicates. Time-resolved laser fluorescence spectroscopy (TRLFS) was used to assess the dissolved and adsorbed U(VI) species on γ-Alumina in the pH range of 6.5–9.0 at temperatures of 25 to 70°C. Initial concentrations of U(VI), carbonate and calcium were 89 μM, 25 mM, and 3.0 mM, respectively. The parallel factor analysis (PARAFAC) was used for chemical speciation by spectrum deconvolution. In addition, a separate solution system with higher U(VI) concentrations (0.1 mM, 1.0 mM) and carbonate concentration of 25 mM was studied with attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy for adsorbed species at 25°C. The electrophoretic mobility measurements were also conducted at 25°C to assess the coordination mechanism of adsorbed species at 25°C. The uranyl hydrolysis species and uranyl tricarbonato species coexist in solution at 25°C. At the same temperature, both species were found to be adsorbed. ATR-FTIR could confirm the adsorption of uranyl tricarbonato species at 25°C, and the electrophoretic mobility measurements suggested that the reaction mechanism is an inner-sphere coordination. However, in comparison with aqueous speciation at 25°C, at elevated temperatures the available pH range of uranyl tricarbonato species was narrow and that for uranyl hydrolysis species was wider. It was evident that two hydrolysis species are adsorbed at elevated temperatures, but no tricarbonato species. The enhanced U(VI) adsorption was observed with temperatures. This could result from the transition of dominance from the concurrent adsorption of uranyl hydrolysis species and uranyl tricarbonato species to two hydrolysis species. It was seen that the trend of enthalpy of adsorption was endothermic. Combining the present results with temperature-dependent adsorption studies on silica and aluminosilicates, a reliable SCM for the subsurface system can be proposed to explain U(VI) migration.

수처리 및 의약바이오 분야에서 유효물질 분리에 활용되고 있는 알루미나 중공사 분리막은 얇은 두께로 인해 취 급 및 적용시 쉽게 파괴되는 단점이 있기 때문에 분리막의 강도를 100 MPa 이상으로 향상시키기 위한 연구가 필요하다. 본 연구에서는 나노입자의 함량을 0, 1, 3, 5 wt%로 증가시켰을 때 제조된 중공사 분리막의 특성을 평가하였다. 그 결과, 나노입 자의 함량이 증가함에 따라 중공사 분리막의 강도는 79 MPa에서 115 MPa로 증가하였으며, 밀도는 1.76 g/m3에서 1.88 g/m3 으로 증가하였고 기공률과 평균기공크기는 각각 51%에서 48%로, 416 nm에서 352 nm로 감소한 것을 확인하였다. 스폰지구 조가 발달하고 스폰지구조의 기공크기가 향상된 알루미나 중공사 분리막은 100 MPa 이상으로 기계적 강도가 향상되었으며, 약 100000 GPU의 높은 질소 투과도 및 약 3000 L/m2h의 높은 물 투과도를 나타내었다. 따라서, γ-알루미나 나노입자를 소 결조제로 첨가하는 것은 α-알루미나 중공사 분리막의 기계적 강도를 효과적으로 증진시키고 높은 투과성능을 유지할 수 있 는 매우 유효한 방법임을 확인하였다.

Estuary is important in terms of biodiversity because it has the characteristics of transition waters, created by the mixing of fresh- and seawater. The estuarine water circulation provides a variety of habitats with different environments by inducing gradients in the chemical and physical environment, such as water quality and river bed structure, which are ultimately the main factors influencing biological community composition. If the water circulation is interrupted, the loss of brackish areas and the interception of migration of biological communities will lead to changes in the spatial distribution of biodiversity. In this study, among the sites covered by the Estuary Aquatic Ecosystem Health Assessment, we selected study sites where changes in biodiversity can be assessed by spatial gradient from the upper reaches of the river to the lower estuarine area. The α-, γ- and β-diversity of diatom, benthic macroinvertebrates, and fish communities were calculated, and they were divided into open and closed estuary data and compared to determine the trends in biodiversity variation due to estuarine circulation. As results, all communities showed higher γ-diversity at open estuary sites. The benthic macroinvertebrate community showed a clear difference between open and closed estuaries in β-diversity, consequently the estuarine transects were considered as a factor that decreases spatial heterogeneity of their diversity among sites. The biodiversity trends analyzed in this study will be used to identify estuaries with low γ- and β-diversity by community, providing a useful resource for further mornitoring and management to maintain estuarine health.

Anion assisted [4 + 2] cycloaddition reaction via indolo[2,3]-dienolate by reacting 1,2-dimethylindole-3-carboxaldehyde with aromatic nitriles using lithium diisopropylamide in terahydrofuran, a facile and convenient regiospecific route designed and developed for the synthesis of γ-carbolines.

We previously showed that γ-glutamyltranspeptidase (GGT), an enzyme involved in glutathione metabolism, in Bacillus subtilis acts as a virulence factor for osteoclastogenesis via the RANKL-dependent pathway. Hence, it can be hypothesized that GGT of periodontopathic bacteria acts as a virulence factor in bone destruction. Because Fusobacterium nucleatum, which is a periodontopathic pathogen, has GGT with a primary structure similar to that of B. subtilis GGT (37.7% identify), the bone-resorbing activity of F. nucleatum GGT was examined here. Recombinant GGT (rGGT) of F. nucleatum was expressed in Escherichia coli and purified using the His tag of rGGT. F. nucleatum rGGT (Fn rGGT) was expressed as a precursor of GGT, and then processed to a heavy subunit and a light subunit, which is characteristic of general GGTs, including the human and B. subtilis enzymes. Osteoclastogenesis was achieved in a co-culture system of mouse calvaria-derived osteoblasts and bone marrow cells. Fn rGGT induced osteoclastogenesis to a level similar to that of B. subtilis rGGT; furthermore, osteoclastogenesis was induced in a dose-dependent manner. These results suggest that F. nucleatum GGT possesses a virulent bone-resorbing activity, which could play an important role in the pathogenesis of periodontitis.

A γ-aminobutyric acid (GABA) producing microorganism was isolated from Sun-Tae Jeotgal, a Korean traditional fermented seafood. Two thousand presumptive lactic acid bacteria (LAB) isolates were screened for GABA production by thin layer chromatography. One isolate, T118, produced GABA profusely, and identified as Lactobacillus brevis. Growth of Lb. brevis T118 was examined during 120 h cultivation in MRS broth under different conditions. Lb. brevis T118 grew well at 30-37℃, initial pH of 4-7, and up to 5% NaCl (w/v). A gene, gadB, encoding glutamate decarboxylase (GAD) was cloned by PCR. gadC encoding a glutamate/GABA antiporter was cloned and gadC located immediately upstream of gadB, indicating gadCB operon structure. The operon structure was confirmed by reverse transcription (RT)-PCR. gadB was overexpressed in Escherichia coli BL21 (DE3) and recombinant GAD was purified. The size of recombinant GAD was 54.4 kDa by SDS-PAGE, which matched well with the calculated size from the nucleotide sequence.

Natural killer (NK) cells are innate lymphocytes that aid in the protection of the host from infectious diseases and cancer. Regulation of cytotoxicity in NK cells is mediated by inhibitory receptors that bind major histocompatibility complex class I (MHC-I) molecules on target cells. Human myelogenous leukemia K562 cells are readily attacked by NK cells, because K562 cells expressed very low levels of MHC-I molecules for inhibitory NK cell receptors. In this study, we compared the ability of γ-irradiated- or mitomycin C (MMC)-treated K562 feeder cells to support expansion and activation of canine NK cells. We isolated CD5 negative cells from canine peripheral blood mononuclear cells by immunomagnetic separation and co-cultured with γ-irradiated (100 Gy)- or MMC (20 μg/mL)-treated K562 cells in the presence of interleukin (IL)-2, IL-15 and IL-21 for 21 days. As a result, number of CD5 negative cells, co-cultured with γ-irradiated- or MMC-treated K562 cells (56.72 ± 13.77 fold or 32.99 ± 10.83 fold), was increased than those of CD5 negetive cells (2.99 ± 1.42 fold). Also, we found that gene expression markers of activated NK cells such as NKp30, NKp44, NKp46, Ly49, NKG2D, CD244, perforin, and granzyme B and production of interferon gamma were similarly upregulated in NK cells co-cultured with γ-irradiated- or MMC-treated K562 cells, respectively. Next, we observed that cytotoxicity of NK cells co-cultured with γ-irradiated K562 cells was more sensitively reacted to canine mammary carcinoma cells than those of MMC-treated K562 cells. These results revealed that γ-irradiated K562 cells are more efficient feeder cells than MMC-treated K562 cells for enhancing NK cells expansion and activation.

Soymilk has been substituted for milk for people who are suffering from lactoseintolerance. In this study γ-aminobutyric acid (GABA) producing lactic acid bacterium, Lactobacillus plantarum LP2, was applied to ferment soymilk for improving its functionality. GABA production was proved in MRS broth supplemented 3% monosodium glutamate (MSG) and soymilk including 10% (w/v) soymilk powder and 5%(w/v) fructooligosaccharide where L. plantarum LP2 was applied. In addition to the soymilk, isolated soy protein (ISP), which was enzyme-treated, was added to it for improving the content of free amino acids including glutamic acid. L. plantarum LP2 was well grown and produced GABA in the soymilk medium.

본 연구는 감마선을 이용한 육종 차조기 추출물을 통해 항염증 효능을 평가하고자 하였다. RAW 264.7 세포에서 MTT를 통해 세포 생존율을 평가하였으며, LPS로 유도한 RAW 264.7 세포에서 ROS, NO, 염증성 사이토카인, NF-κB, COX-2 등을 ELISA, Luminex 및 PCR로 측정하였다. 그 결과, 육종 차조기 추출물은 25 ㎍/㎖ 이하에서 세포독성이 없었으며, LPS로 유도된 RAW 264.7 세포에 서 ROS, NO, 사이토카인(IL-1β, IL-6, TNF-α)의 생성을 억제하였다. 또한, NF-κB, COX-2의 발현을 감소시켜 육종 차조기 추출물은 뛰어난 항염증 효과를 보였다. 이와 같은 결과는 염증 매개체로 인해 발생하는 질환을 개선하기 위한 새로운 건강식품 및 치료제의 원료로 개발될 수 있다.