• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.69-70
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• 2002

• Journal of the Korean Ceramic Society
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• v.39 no.5
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• pp.473-478
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• 2002

${\alpha}-Al_2O_3$ platelets were synthesized by microwave heating the two different powder mixtures of $Al_2(SO_4)_3+2Na_2SO_4$ and ${\gamma}-Al_2O_3+2Na_2SO_4$ using flux method. DTA-TG, XRD and SEM were used to investigate the effect of microwave on the formation of ${\alpha}-Al_2O_3$ platelets. In the case of the mixture of $Al_2(SO_4)_3+2Na_2SO_4$, the microwave heated sample was ${\alpha}-Al_2O_3$ platelets composed of aggregates with smaller particle size compared to the conventionally heated sample. In the case of the mixture of ${\gamma}-Al_2O_3+2Na_2SO_4$, the temperature to form ${\alpha}-Al_2O_3$ platelets by the microwave heating was lower than that by the conventional heating and the morphology of the microwave heated sample was similar to that of the conventionally heated sample except that the microwave heated sample had smaller particle size compared to the conventionally heated sample.

• Steel and Composite Structures
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• v.36 no.6
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• pp.711-727
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• 2020

In the present research, the free vibration analysis of functionally graded (FG) nanocomposite deep spherical shells reinforced by graphene platelets (GPLs) on elastic foundation is performed. The elastic foundation is assumed to be Winkler-Past ernak-type. It is also assumed that graphaene platelets are randomly oriented and uniformly dispersed in each layer of the nanocomposite shell. Volume fraction of the graphene platelets as nanofillers may be different in the layers. The modified HalpinTsai model is used to approximate the effective mechanical properties of the multilayer nanocomposite. With the aid of the first order shear deformation shell theory and implementing Hamilton's principle, motion equations are derived. Afterwards, the generalized differential quadrature method (GDQM) is utilized to study the free vibration characteristics of FG-GPLRC spherical shell. To assess the validity and accuracy of the presented method, the results are compared with the available researches. Finally, the natural frequencies and corresponding mode shapes are provided for different boundary conditions, GPLs volume fraction, types of functionally graded, elastic foundation coefficients, opening angles of shell, and thickness-to-radius ratio.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.73-79
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• 1995

Incidents of seafood and massive fish kills have been rapidly increasing in both frequency and geographical distribution and the socioeconomic impacts brought by those incidents. However, the biological origins of those marine toxins have not been well clarified. Most of the marine organisms investigated are filter-feeder, which accumulate toxins from their food and/or their symbiotic microalgae. We have examined the action on rabbit platelets of marine toxins isolated from cultured dinoflagellates and sponge collected at Okinawa. Maitotoxin (MTX) is a water-soluble toxin isolated from the cultured dinoflagellate Gambierdiscus toxicus which causes a seafood poisoning in tropical regions. Zooxanthellatoxin A (ZT-A) was isolated from exteracts of cultured symbiotic dinoflagellate Symbiodinium sp. (socalled zooxanthella) from flatworms of the genus Amphiscolops collected at Okinawan marine sponge Theonella sp. MTX caused a disaggregation and a dissolution of large aggregates. ZT-A caused a dissolution of small aggregates followed by a increment of light tranmission. TZ-A caused an initial and transient shape change followed by a sustained aggregation and a increment of large aggregates. In conclusion, marine toxins exert unique patterns on the light trasmission and the size of aggregates in rabbit platelets by their concentrations and kinds

• Journal of Society of Preventive Korean Medicine
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• v.2 no.1
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• pp.1-11
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• 1998

This experimental study was carried out to evaluate the effort of Lulianwendang on number of white blood cells and blood platelets in anti-neoplastic agents treated mice. The results were as follows; 1. The group of adriamycine treated and Lulianwendang administered mice were increased significantly in WBC as compared with control group.: 2. The group of cyclophosphamide injected and Lulianwendang administered mice were increased significantly in WBC as compared with control group. 3. The group of vincristin injected and Lulianwendang administered mice were increased significantly in W5C as compared with control group. 4. The group of adriamycine treated and Lulianwendang administered mice were increased significantly in blood platelets as compared with control group. 5. The group of cyclophosphamide injected and Lulianwendang administered mice were increased significantly in blood platelets as compared with control group. 6. The group of vincristin injected and Lulianwendang administered mice were increased significantly in blood platelets as compared with control group. According to the results, we can suggest that Lulianwendang has the hematopoiesis effects against anti-neoplastic agents treated mice.

• Steel and Composite Structures
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• v.27 no.3
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• pp.255-271
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• 2018

This paper deals with the transient dynamic analysis and elastic wave propagation in a functionally graded graphene platelets (FGGPLs)-reinforced composite thick hollow cylinder, which is subjected to shock loading. A micromechanical model based on the Halpin-Tsai model and rule of mixture is modified for nonlinear functionally graded distributions of graphene platelets (GPLs) in polymer matrix of composites. The governing equations are derived for an axisymmetric FGGPLs-reinforced composite cylinder with a finite length and then solved using a hybrid meshless method based on the generalized finite difference (GFD) and Newmark finite difference methods. A numerical time discretization is performed for the dynamic problem using the Newmark method. The dynamic behaviors of the displacements and stresses are obtained and discussed in detail using the modified micromechanical model and meshless GFD method. The effects of the reinforcement of the composite cylinder by GPLs on the elastic wave propagations in both displacement and stress fields are obtained for various parameters. It is concluded that the proposed micromechanical model and also the meshless GFD method have a high capability to simulate the composite structures under shock loadings, which are reinforced by FGGPLs. It is shown that the modified micromechanical model and solution technique based on the meshless GFD method are accurate. Also, the time histories of the field variables are shown for various parameters.

• Proceedings of the Ginseng society Conference
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• 1993.09a
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• pp.94-101
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• 1993

Lipophilic fraction(LF) from Panax ginseng C.A. Meyer inhibited the aggregation of human platelets induced by th rombin(0.1u/$m{\ell}$). LF and Molsidomine(vasodilator) induced the stimulation of cGMP - elevation and 50KD - Phosphorylation. and then the inhibition of 20KD - Phosphorylation in human platelets activated by thrombin. LF also inhibited the $Ca^{2-}-influx$ into platelets. When rat(SD : male) was fed with LF, the level of cGMP was increased in rat platelets stimulated by collagen and thrombin. On the other hand. verapamil, $Ca^{2-}-antagonist$ increased cAMP level ;n platelet stimulated by thrombin. but LF does not affected. However LF potently inhibited the thromboxane $A_2(TXA_2)$ production. The results suggest that the inhibitory effects of LF are mediated by regulation the phosphorylatior. of 50KD via cGMP-elevation and depend upon the decrease of $TXA_2$ level.

• Journal of Nutrition and Health
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• v.25 no.5
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• pp.339-350
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• 1992

This study was performed to investigate the effect on polyunsaturate fatty acid diets and feeding periods on the antithrombosis. the hematological changes in the blood and fatty acid compositions of platelets in rats. Each group of rats was fed a diet containing 20%(W/W) corn oil beef tallow sardine oil and the general stock diet for 10, 20. 40 and 80 days. Rats fed sardine oil diet showed significantly longer bleeding time than any other diet groups after 20 days feeding The whole blood clotting time of sardine oil group fed for 80 days was increased significantly. The number of platelet and the concentration of hemoglobin showed no significant difference among all groups. The number of white blood cell was decreased continously in sardine oil group after 10 days feeding. The level of malondialdehyde generation during thrombin-induced aggregation of platelets was decreased continously in sardine oil grou after 20 days feeding. With regard to the composition of platelet fatty acid the ratio of eicosapentaenoic acid(EPA 20: 5 $\omega$-3) to arachidonic acid(AA 20:4 $\omega$-6) was increased in sardine oil group but decreased in corn oil groups and beef tallow groups with days. In conclusion the rats fed sardine oil diet for more than 20 days showed the fact that EPA induced the antithrombosis. the changes in number of white blood cell and the fatty acid composition of platelets.

• Journal of Veterinary Clinics
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• v.15 no.2
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• pp.352-357
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• 1998

Effects of chicken egg white derivatives (EWD and EF-203) on the changes of blood cells and the neutrophil phagocytic activity were examined in the rats. Rats were administered orally with either EWD (200 mg/kg) or EF-203 (200 mg/kg) for 3 days. Thereafter, the changes of blood cell values (RBC, WBC, platelets, PCV, differential count of neutrophils) and the phagocytic activity of neutrophils were evaluated for 7 days. The numbers of WBC and the differential count of neutrophils of rats administered with either EWD or EF-203 were significantly increased (p

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.55-58
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• 2004

Cell separation from peripheral blood was investigated using surface-modified polyurethane (PU) membranes with different functional groups. Both red blood cells and platelets could pass through unmodified PU and PU-SO$_3$H membranes, while the red blood cells preferentially passed through PU-N(C$_2$H$_{5}$ )$_2$ and PU-NHC$_2$H$_4$OH membranes. The permeation ratio of T and B cells was less than 25% for the surface-modified and unmodified PU membranes. CD34$^{+}$ cells have been recognized as various kinds of stem cells including hematopoietic and mesenchymal stem cells. The adhesiveness of CD34$^{+}$ cells on the PU membranes was found to be higher than that of red blood cells, platelets, T cells or B cells. Overall, the adhesiveness of blood cells on the PU membranes increased in the following order: red blood cells $\leq$ platelets ＜ T cells $\leq$ B cells ＜ CD34$^{+}$ cells. Treatment of PU-COOH membranes with a human albumin solution to detach adhered blood cells, allowed recovery of mainly CD34$^{+}$ cells in the permeate, while both red blood cells and platelets could be isolated in the permeate using unmodified PU membranes. The PU membranes showed different permeation and recovery ratios of specific cells depending on the functional groups attached to the membranes.mbranes.