• 논리연구
• /
• 제5권1호
• /
• pp.45-61
• /
• 2001

이 글에서 우리는 연관 명제계산과 무한다치 명제계산 사이의 관계를 살핀다. 구체적으로 우리는 연관 명제계산 $BN_{c1}$이 무한다치 명제계산 $L{\L}C^+$를 포함하는 확장 체계로 간주될 수 있다는 것을 보인다. 즉 $L{\L}C^+$에 직관주의 명제논리에 사용된 부정을 첨가한 후, $BN_{c1}$이 이 체계 $L{\L}C^+$로 변역될 수 있다는 것을 보인다.

• 한국재료학회지
• /
• 제20권4호
• /
• pp.194-198
• /
• 2010

Cubic boron nitride (c-BN) is a promising material for use in many potential applications because of its outstanding physical properties such as high thermal stability, high abrasive wear resistance, and super hardness. Even though 316L austenitic stainless steel (STS) has poor wear resistance causing it to be toxic in the body due to wear and material chips, 316L STS has been used for implant biomaterials in orthopedics due to its good corrosion resistance and mechanical properties. Therefore, in the present study, c-BN films with a $B_4C$ layer were applied to a 316L STS specimen in order to improve its wear resistance. The deposition of the c-BN films was performed using an r.f. (13.56 MHz) magnetron sputtering system with a $B_4C$ target. The coating layers were characterized using XPS and SEM, and the mechanical properties were investigated using a nanoindenter. The friction coefficient of the c-BN coated 316L STS steel was obtained using a pin-on-disk according to the ASTM G163-99. The thickness of the obtained c-BN and $B_4C$ were about 220 nm and 630 nm, respectively. The high resolution XPS spectra analysis of B1s and N1s revealed that the c-BN film was mainly composed of $sp^3$ BN bonds. The hardness and elastic modulus of the c-BN measured by the nanoindenter were 46.8 GPa and 345.7 GPa, respectively. The friction coefficient of the c-BN coated 316L STS was decreased from 3.5 to 1.6. The wear property of the c-BN coated 316L STS was enhanced by a factor of two.

• Carbon letters
• /
• 제11권4호
• /
• pp.332-335
• /
• 2010

The photodegradation of the model compounds Quinol, an aromatic organic compound and Acid blue FFS, an acid dye of chemical class Triphenylmethane was studied by using illumination with UV lamp of light intensity 250W. $TiO_2$ and $TiO_2$ doped with Boron and Nitrogen was used as catalyst. The sol-gel method was followed with titanium isopropoxide as precursor and doping was done using Boron and Nitrogen. In photocatalytic degradation, $TiO_2$ and doped $TiO_2$ dosage, UV illumination time and initial concentration of the compounds were changed and examined in order to determine the optimal experimental conditions. Operational time was optimized for 360 min. The optimum dosage of $TiO_2$ and BN doped $TiO_2$ was obtained to be 2 $mgL^{-1}$ and 2.5 $mgL^{-1}$ respectively. Maximum degradation % for quinol and Blue FFS acid dye was 78 and 95 respectively, at the optimum dosage of BN-doped $TiO_2$ catalyst. It was 10 and 4% higher than when undoped $TiO_2$ catalyst was used.

• Nutrition Research and Practice
• /
• 제17권6호
• /
• pp.1043-1055
• /
• 2023

BACKGROUND/OBJECTIVES: The fruit of Cydonia oblonga Miller (COM) is used traditionally in Mediterranean region medicine to prevent or treat obesity, but its mechanism of action is still unclear. Beyond a demonstrated anti-obesity effect, the fruit was tested for the mechanism of adipogenesis in 3T3-L1 preadipocytes. MATERIALS/METHODS: 3T3-L1 preadipocytes were cultured for 8 days with COM fruit extract (COME) at different concentrations (0-600 ㎍/mL) with adipocyte differentiation medium. The cell viability was measured using an MTT assay; triglyceride (TG) was stained with Oil Red O. The expression levels of the adipogenesis-related genes and protein expression were analyzed by reverse transcription polymerase chain reaction and Western blotting, respectively. RESULTS: COME inhibited intracellular TG accumulation during adipogenesis. A COME treatment in 3T3-L1 cells induced upregulation of the adenosine monophosphate-activated protein kinase (AMPK)α phosphorylation and downregulation of the adipogenic transcription factors, such as sterol regulatory element-binding protein 1c, peroxisome proliferator-activated receptor γ, and CCAAT/enhancer binding protein α. The COME treatment reduced the mRNA expression of fatty acyl synthetase, adenosine triphosphate-citrate lyase, adipocyte protein 2, and lipoprotein lipase. It increased the mRNA expression of hormone-sensitive lipase and carnitine palmitoyltransferase I in 3T3-L1 cells. CONCLUSIONS: COME inhibits adipogenesis via the AMPK signaling pathways. COME may be used to prevent and treat obesity.

• Natural Product Sciences
• /
• 제24권1호
• /
• pp.36-39
• /
• 2018

Phytochemical analysis of Boehmeria nivea (Bn) leaves by medium pressure liquid chromatography led to the isolation of a flavonoid glycoside identified by spectroscopic analysis as rutin. The amount of rutin in the leaves of Bn harvested from nine regions in South Korea (Bn 1-9) which were collected on the months of June, July, August, and September was determined by HPLC-UV analysis. A gradient elution program that utilizes a $Discovery^{(R)}$ C18 ($4.6{\times}250mm$, $5{\mu}m$) column and mobile phase composed of 1% acetic acid-water: acetonitrile (90:10 to 60:40 for min) was followed. The injection volume and flow rate were $10{\mu}l$ and 1 mL/ min, respectively. UV detection was set at 350 nm. Results show that Bn-8 harvested in September reported the highest content of rutin among the samples analyzed. This study provides a basis for the optimal harvest time of Bn which maximizes the yield of rutin.

• Journal of Applied Biological Chemistry
• /
• 제66권
• /
• pp.359-368
• /
• 2023

This study aims to explore the impact of Krill Oil (KO, Superba^TM Boost) on skin moisturization regulation. The research involved five groups: an intact control, a reference group (L-AA 100 mg/kg), and KO groups (400, 200, and 100 mg/kg), each comprising ten mice. Oral administration was conducted for 8 weeks (56 days), during which changes in body weight, hyaluronan, collagen type 1 (COL1), transforming growth factor-β1 (TGF-β1), ceramide, and water contents were analyzed in dorsal back skin tissue. Real-time PCR was employed to assess gene expression related to hyaluronic acid synthesis (HAS1, HAS2, HAS3), COL1 synthesis (COL1A1 and COL1A2), and TGF-β1. Results demonstrated that KO administration significantly increased hyaluronan content, hyaluronic acid synthesis (HAS1, HAS2, HAS3), COL1 content, COL1 synthesis (COL1A1 and COL1A2), TGF-β1 content, TGF-β1 mRNA expression, ceramide content, and water content in a concentration-dependent manner compared to the intact control. Importantly, no discernible disparities were noted between the KO and L-AA groups, even though they received equivalent oral dosages. This study accentuates the potential utility of exogenous KO in the regulation of skin moisture, thus positioning it as a promising avenue for the development of nutricosmetics. Future research endeavors should delve into the role of KO in safeguarding against both intrinsic and extrinsic aging-related skin manifestations, as well as its potential to ameliorate skin wrinkles, in conjunction with its moisturizing attributes.

• Journal of Microbiology and Biotechnology
• /
• 제17권8호
• /
• pp.1284-1290
• /
• 2007

This study was conducted to investigate the antibacterial activity and shelf-life extension effect of iceberg lettuce packed in BN/PE film. The BN/PE film has a strong microbial suppression effect on pathogenic bacteria such as Escherichia coli, Salmonella enteritidis, and S. typhimurium. The number of psychrophiles and mesophiles during 5 days of cold storage of fresh-cut iceberg lettuce at $10^{\circ}C$ packaged in BN/PE film was strictly suppressed in comparison with other tested films (OPP, PE, and PET film). When fresh processed iceberg lettuce was processed and stored under the current conditions, the shelf-life of the product was longer than 5 days in the BN/PE film package, whereas the shelf-life when using the other films tested, PE, OPP and PET, was no longer than 3-4 days. The decay rates of the iceberg lettuce packed in the BN/PE film was maintained at $29.8{\pm}2.1%$ on the 5th day of preservation. The samples packed in BN/PE film maintained an excellent visual quality during the 3 days of storage without significant differences in comparison with the initial visual quality. No browning was observed in the samples packed in BN/PE film for up to 3 days. The texture of shredded iceberg lettuce packaged in BN/PE film remained unchanged up to 3 days, and then a moderate decrease in texture was observed after 4 days of storage. In addition, the overall acceptability of fresh-cut iceberg lettuce packaged in BN/PE film did not change for up to 3 days, whereas the samples packaged in the other films were inedible by 3 days of storage. In conclusion, the shelf-life of fresh-cut iceberg lettuce packaged in the BN/PE film was extended to more than 5 days at $10^{\circ}C$, whereas that in the other films was 2 days at $10^{\circ}C$. Therefore, the shelf-life extension effect of the fresh-cut iceberg lettuce in BN/PE film packaging was very effective compared with the other films tested.

• 원예과학기술지
• /
• 제31권3호
• /
• pp.299-307
• /
• 2013

A radish (Raphanus sativus L.) polygalacturonase-inhibiting protein (PGIP) gene was cloned and compared to the PGIP gene (BrPGIP2) from Chinese cabbage (Brassica rapa ssp. pekinensis) in order to gain more information on controlling a disease and improving produce quality. To clone the radish PGIP gene, primers were designed based on conserved sequences of two PGIP genes (BnPGIP1 and BnPGIP2) from rape (B. napus L. ssp. oleifera), Chinese cabbage and Arabidopsis thaliana. PCR cloning was performed with cDNA from the stigma of radish 'Daejinyeoreum' as a template to confirm DNA fragments which were about 600 base pair in size. Sequence analysis revealed 84.1% homology with BrPGIP2 and 70.1% with BnPGIP1. DNA walking was conducted to confirm the open reading frame of 972 bp, and the gene was named RsPGIP1. RsPGIP1 consisting with 323 amino acids (aa) has a high leucine content (54/323) and contains 10 leucine-rich repeat domains, as do most BrPGIPs of Chinese cabbage. The gene expression of RsPGIP1 was induced by abiotic stresses and methyl jasmonate. It showed enrichment in the stigma and the primary root than a leaf. Cloning RsPGIP1 will aid to further apply practices on postharvest quality maintenance and disease control of the root.

• Plant Biotechnology Reports
• /
• 제4권2호
• /
• pp.165-172
• /
• 2010

Genes that are expressed early in specific response to high salinity conditions were isolated from rapeseed plant (Brassica napus L.) using an mRNA differential display method. Five PCR fragments (DD1.5) were isolated that were induced by, but showed different response kinetics to, 200 mM NaCl. Nucleotide sequence analysis and homology search revealed that the deduced amino sequences of three of the five cDNA fragments showed considerable similarity to those of ${\beta}$-mannosidase (DD1), tomato Pti-6 proteins (DD5), and the tobacco harpin-induced protein hin1 (DD4), respectively. In contrast, the remaining clones, DD3 and DD2, did not correspond to any substantial existing annotation. Using the DD3 fragment as a probe, we isolated a full-length cDNA clone from the cDNA library, which we termed BnSWD1 (Brassica napus salt responsive WD40 1). The predicted amino-acid sequence of BnSWD1 contains eight WD40 repeats and is conserved in all eukaryotes. Notably, the BnSWD1 gene is expressed at high levels under salt-stress conditions. Furthermore, we found that BnSWD1 was upregulated after treatment with abscisic acid, salicylic acid, and methyl jasmonate. Our study suggests that BnSWD1, which is a novel WD40 repeat-containing protein, has a function in salt-stress responses in plants, possibly via abscisic acid-dependent and/or -independent signaling pathways.

• Clinical and Experimental Vaccine Research
• /
• 제13권3호
• /
• pp.242-252
• /
• 2024

Purpose: In this study, an in-house enzyme-linked immunosorbent assay (ELISA) was developed and validated. The titer of ELISA was calculated using the reference line (RFL) method based on the standard curve drawn using the international reference anti-mouse serum NIBSC (National Institute for Biological Standards and Control) 97/642. Materials and Methods: In the development step, signal to noise was depicted to select the buffers that showed the most appropriate ratio. In the validation step, standard range, precision, dilution linearity, and specificity were confirmed, and RFL and parallel line (PLL) methods were compared in precision and dilution linearity. Results: Coating concentration for plate was achieved at 0.1 ㎍/mL for pertussis toxin (PT), 0.15 ㎍/mL for filamentous hemagglutinin antigen (FHA), and 0.25 ㎍/mL for pertactin (PRN). The signal to noise ratio was 22.02 for PT, 14.93 for FHA, and 8.02 for PRN with 0.25% goat serum in phosphate-buffered saline (PBS) as a dilution buffer, and 2% skim milk in PBS as a blocking buffer. Based on the precision results, we assessed the lower limit of quantification by 1, 0.2, and 1.5 EU/mL concentration for PT, FHA, and PRN which met the ICH (International Council for Harmonization) M10 criteria of a 25% accuracy and total error of 40%. In specificity, homologous serum was spiked into heterologous serum and the accuracy met the criteria. There was no difference in the results between RFL and PLL calculations (p-value=0.3207 for PT, 0.7394 for FHA, 0.2109 for PRN). Conclusion: ELISA validated with RFL calculation method in this study is a relatively accurate assay for mouse humoral immunogenicity test.