• Analytical Science and Technology
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• v.6 no.5
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• pp.501-508
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• 1993

In n/${\gamma}$ mixed field of $^{241}Am-Be$(${\alpha}$, n) neutron source, we seperated the neutron component from gamma ray component. At the center of the detector, $^6Li$ was doped on the cerium activated glass plate for $^6Li$(${\alpha}$, n)T nuclear reaction. The time differences of the light following excitations by different scintillators, BC501($C_8H_{10}$) and cerium, and by the same scintillator for different radiations as neutrons and gamma-rays are used to apply the methods of PSD(Pulse Shape Discriminator) and CFD(Constant Fraction Discriminator). The figure of merit of $^6Li$ fast neutron spectrometer is estimated as 1.36.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1593-1597
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• 2006

We hope to evaluate the effects of Gami-Choakwiyeum (GCKY) on the PPAR-${\gamma}$’ in the OVA induced asthma mouse model. Female BALB/c mice, 8 weeks of age and free of murine specific pathogens were used. Mice were sensitized by intraperitoneal injection of OVA emulsified in aluminum hydroxide in a total volume of 200 ${\mu}{\ell}$ on one day and 14 days. On 21, 22, and 23 days after the initial intraperitoneal injection of OVA, the mice were challenged using an ultrasonic nebulizer. GCKY was administered 7 times by oral gavage at 24 hour intervals fromdays 19 after intraperitoneal injection of OVA. Bronchoalveolar lavage was perfromed 72 hours after the last challenge, and total cell numbers in the BAL fluid were counted. Also, the level of PPAR-${\gamma}$ of normal and OVA-induced asthma moused with/without administration of GCKY were measured by Western blot analysis. For the histologic examination, the specimens were stained with hematoxylin 2 and eosin-Y.(H & E). Numbers of total cells were increased significantly at 72 h after OVA inhalation compared with numbers of total cells in the normal and the administration of GCKY. Especially, the increased numbers of eosinophils in BAL fluids after OVA inhalation were significantly increased. However, the numbers of eosinophils reduced by the administration of GCKY. Western blot analysis revealed that PPAR-${\gamma}$ levels in nuclear level were increased slightly after OVA inhalation compared with the levels in the normal group. After the administration of GCKY, PPAR-${\gamma}$ levels in cytosolic and nuclear levels at 72 h after OVA inhalation were markedly increased. On pathologic examination, there were many acute inflammatory cells around the alveoli, bronchioles, and airway lumen of mice with OVA-induced asthma compared with inflammatory cells in the normal group. However, acute inflammatory cells around alveoli, bronchioles, and airway lumen markedly decreased after administration of GCKY, GCKY can increase a PPAR-${\gamma}$ level and could be an effective treatment in asthma patients through the PPAR-${\gamma}$ mechanism for bronchial asthma.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.6
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• pp.816-822
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• 2015

The objective of this study was to evaluate the anticancer effects of gamma-irradiated apigenin against various human cancer cells. Structural changes were analyzed by high pressure liquid chromatography. Gamma-irradiated apigenin showed a new peak distinguished from the main peak of apigenin (non-irradiated). Cytotoxic effects in human normal cells (HS68) were not observed upon gamma-irradiated and non-irradiated apigenin treatment. However, gamma-irradiated apigenin treatment significantly increased cytotoxicity against non-small lung cancer cells. For apoptosis induction activity tested by Annexin V/PI staining, gamma-irradiated apigenin showed a stronger effect than non-irradiated apigenin, and the level of reactive oxygen species was apparently elevated by gamma-irradiated apigenin treatment. These results suggest that gamma irradiation could be an effective method for development of a new physiological compound from an original compound by inducing structural changes.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.92-97
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• 2015

The aim of this study is to examine the removal efficiency of pathogen (Escherichia coli O157:H7 and Salmonella typhimurium) on meat and fish products (packing condition: vacuum or not and storage temperature: $4^{\circ}C$ or $-20^{\circ}C$) repeatedly exposed at low-dose gamma irradiation. In case of meat products (beef and chicken), E. coli O157:H7 was not observed at the level of 2 kGy single gamma irradiation and 0.5 kGy repeated gamma irradiation and S. Typhimurium was not observed at the level of 2 kGy single gamma irradiation and 1 kGy repeated gamma irradiation. In case of fish products, E. coli O157:H7 and S. Typhimurium were not detected at the level of 0.5 kGy single and repeated gamma irradiation. These results showed that microorganisms on fish products were more efficiently removed than those of meat products with low-dose gamma irradiation. Generally, each packing condition made no difference. However, the products (fish and meat) stored at $-20^{\circ}C$ needed more higher dose gamma irradiation than products at $4^{\circ}C$.

• Journal of the Korean Ceramic Society
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• v.39 no.3
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• pp.272-277
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• 2002

Aluminum nitride (AlN) powders and whiskers were synthesized by a modified carbothermal reduction and nitridation where a ($NH_4)[Al(ethylenediaminetetraacetate)]{\cdot}2H_2O$ complex is used as precursor. The AlN powders were obtained by calcining the complex without mixing any carbon source under a flow of nitrogen in the temperature range 1200∼1500$^{\circ}$C and then burning out the residual carbon. The nitridation process was investigated by $^{27}Al$ magic-angle spinning (MAS) unclear magnetic resonance, infrared spectroscopy and X-ray diffraction. The complex is pyrolyzed, converted to ${\rho}$- and ${\gamma}$- alumina and then nitridated to AlN without ${\gamma}-{\alpha}$ alumina transition. The morphology of ${\gamma}$-alumina, when it was converted to AlN, was retained, strongly indicating that ${\gamma}$-alumina is converted to AlN through solid-state $AlO_xN_y$, not through gaseous intermediates such as aluminum and aluminaum suboxides. AlN whiskers were obtained, when a (0001) sapphire was used as a catalyst.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3281-3289
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• 2011

The materials composed of the 3d series transition metals are introduced into the hydrocarbon steam-reforming reaction in order to enhance the $H_2$ production and abruptly depress the catalytic deactivation resulting from the strong sintering between the Ni component and the ${\gamma}-Al_2O_3$ support. The conventional impregnation method is used to synthesize the Ni/3d series metal/${\gamma}-Al_2O_3$ materials through the sequentially loading Ni source and the 3d series metal (Ti, V, Cr, Mn, Fe, Co, Cu, and Zn) sources onto the ${\gamma}-Al_2O_3$ support. The Mnloaded material exhibits a significantly higher reforming reactivity than the conventional Ni/${\gamma}-Al_2O_3$ and the other Ni/3d series metal/${\gamma}-Al_2O_3$ materials. Particularly the addition of Mn selectively improves the $H_2$ product selectivity by eliminating the formation of $CH_4$ and CO. The $H_2$ production is maximized at a value of 95% over Ni(0.3)/Mn(0.3)/${\gamma}-Al_2O_4$(1.0) with a butane conversion of 100% above $750^{\circ}C$ for up to 55 h.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.2
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• pp.67-75
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• 2013

Objective: To investigate the effect of peroxisome proliferator activated receptor ${\gamma}$(PPAR${\gamma}$) agonist on the cell proliferation properties and expression of human telomerase reverse transcriptase (hTERT) and aromatase in cultured endometrial stromal cell (ESC) from patients with endometriosis. Methods: Human endometrial tissues were obtained from women with endometriosis and healthy women (controls) using endometrial biopsy. Isolated ESCs were cultured and the cell proliferation was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay and expression of hTERT, aromatase, and cyclooxygenase (COX)-2 by western blotting according to the addition of rosiglitazone (PPAR${\gamma}$ agonist). Results: We demonstrate that the cultured ESCs of endometriosis showed hTERT protein overexpression and increased cellular proliferation, which was inhibited by rosiglitazone, in a dose-dependent manner. At the same time, PPAR${\gamma}$ agonist also inhibited aromatase and COX-2 expression, resulting in decreased prostaglandin $E_2$ production in the ESCs of endometriosis. Conclusion: This study suggests that PPAR${\gamma}$ agonist plays an inhibitory role in the proliferative properties of eutopic endometrium with endometriosis by down-regulation of hTERT and COX-2 expression; this could be a new treatment target for endometriosis.

• The korean journal of orthodontics
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• v.23 no.2 s.41
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• pp.229-248
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• 1993

[ $Interferon-\gamma$ ] has been suggested as a cytokine of connective tissue stabilizer. In addition, it has also been demonstrated that this cytokine inhibited bone remodeling activities of the bone derived cells. In order to illuminate the effects of this cytokine in orthodontic force induced bone remodeling, it was administered to primary cultured periodontal ligament cells which have been known to have some osteoblast like characteristics. $Interferon-\gamma$ slightly decreased $[^3H]thymidine$ incorporation rate without a significant change in the total cellular DNA content up to 1000 U/ml, which meant these doses were not cytotoxic to the cell. Total protein synthesis was not influenced by various concentration of interferon-y whether it was determined by the $[^3H]proline$ incorporation rate or by the Lowry smethod. The effect of $interferon-\gamma$ on the individual protein was, however, differential, ie, it increased $[^3H]proline$ incorporation into the noncollagenous protein marginally, while it decreased $[^3H]proline$ incorporation into the collagen, so that it caused dose-dependent suppression of the relative collagen synthesis. On the contrary, the fibronectin synthesis determined by the ELISA was increased by 1000 U/ml of $interferon-\gamma$. The differential effects of the interferon-y on the collagen and fibronectin synthesis exhibited not only their protein level but also the steady state mRNA level. $Interferon-\gamma$ decreased steady state level of ${\alpha}1(I)$ procollagen mRNA significantly, while showing no significant changes in the fibronectin mRNA level. In addition to this, it was also found that indomethacin did not affect on the $interferon-\gamma$ induced collagen decrease in this cell, which meant prostaglandins were not involed in the process of $interferon-\gamma$ induced collagen decrease. So it can be concluded that the incubation of periodontal ligament cells with 1000 U/ml of $interferon-\gamma$ for 24 hr showed differential effects on the type I collagen and fibronectin gene expression. The decrease in relative collagen synthesis in the protein level was related with decrease in the steady state level of mRNA, while the increase in the fibronectin synthesis in the protein level was not correlated with the mRNA level.

• Kyungpook Mathematical Journal
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• v.54 no.2
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• pp.157-163
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• 2014

For a finite subset ${\Lambda}$ of $\mathbb{N}_0{\times}\mathbb{N}_0$, where $\mathbb{N}_0$ is the set of nonnegative integers, we say that a complex data ${\gamma}_{\Lambda}:=\{{\gamma}_{ij}\}_{(ij){\in}{\Lambda}}$ in the unit disc $\mathbf{D}$ of complex numbers has a cyclic subnormal completion if there exists a Hilbert space $\mathcal{H}$ and a cyclic subnormal operator S on $\mathcal{H}$ with a unit cyclic vector $x_0{\in}\mathcal{H}$ such that ${\langle}S^{*i}S^jx_0,x_0{\rangle}={\gamma}_{ij}$ for all $i,j{\in}\mathbb{N}_0$. In this note, we obtain some sufficient conditions for a cyclic subnormal completion of ${\gamma}_{\Lambda}$, where ${\Lambda}$ is a finite subset of $\mathbb{N}_0{\times}\mathbb{N}_0$.

• Kyungpook Mathematical Journal
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• v.55 no.2
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• pp.279-287
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• 2015

A subset S of V (G), where G is a graph without isolated vertices, is a double dominating set of G if for each $x{{\in}}V(G)$, ${\mid}N_G[x]{\cap}S{\mid}{\geq}2$. This paper, shows that any positive integers a, b and n with $2{\leq}a<b$, $b{\geq}2a$ and $n{\geq}b+2a-2$, can be realized as domination number, double domination number and order, respectively. It also characterize the double dominating sets in the Cartesian and tensor products of two graphs and determine sharp bounds for the double domination numbers of these graphs. In particular, it show that if G and H are any connected non-trivial graphs of orders n and m respectively, then ${\gamma}_{{\times}2}(G{\square}H){\leq}min\{m{\gamma}_2(G),n{\gamma}_2(H)\}$, where ${\gamma}_2$, is the 2-domination parameter.