Abstract:The antithrombotic and antiplatelet activities of Korean red ginseng extract (KRGE) were examined on rat carotid artery thrombosis in vivo and platelet aggregation in vitro and ex vivo. The KRGE significantly prevented rat carotid arterial thrombosis in vivo in a dose-dependent manner. Administration of the KRGE to rats significantly inhibited adenosine diphosphate (ADP)-and collagen-induced platelet aggregation ex vivo, although it failed to prolong coagulation times such as activated partial thromboplastin and prothrombin time indicating that the antithrombotic effect of the red ginseng may be due to its antiplatelet aggregation rather than anticoagulation effect. In line with the above observations, the red ginseng inhibited the U46619-, arachidonic acid-, collagen-and thrombin-induced rabbit platelet aggregations in vitro in a concentrationdependent manner, with IC 50 values of 390 ± 15, 485 ± 19, 387 ± 11 and 335 ± 15 µg/ml, respectively. Consistently, serotonin secretion was also inhibited by ginseng in the same pattern. These results suggest that the red ginseng has a potent antithrombotic effect in vivo, which may be due to the antiplatelet rather than the anticoagulation activity, and the red ginseng intake may be beneficial for individuals with high risks of thrombotic and cardiovascular diseases.Platelets not only play a critical role in normal haemostasis, but are also important contributors to thrombotic disorders, especially cerebral vascular diseases such as transient ischaemic attack [1], ischaemic heart diseases such as myocardial infarction [2,3], and peripheral vascular diseases [4]. Disruption of the endothelium by trauma, or atherosclerosis, allows platelets to come into contact with and adhere to exposed subendothelial structures, such as collagen and von Willebrand factor [5][6][7][8] and to interact with soluble agonists, such as ADP and thrombin, both of which were exposed or generated at the injury site [9]. Upon various agonists clustering with respective receptors on platelet surface, the intracellular signals will be activated and platelets will change shape, spread, and release or secrete activating substances to recruit platelets to the developing thrombus. Thus, antiplatelet therapy is a useful means of preventing acute thromboembolic artery occlusions in cardiovascular diseases.Panax ginseng, the herbal root of Panax ginseng C. A. Meyer, has been used for more than 2000 years as a component of traditional Asian medicines to promote health and treat illness. Although various forms of ginseng were processed for use, white ginseng and red ginseng were used most widely. White ginseng is air-dried, while red ginseng is produced by steaming and drying of raw ginseng. It has been reported that red ginseng was pharmacologically more active than white ginseng. The different biological activities of red and white ginsengs may result from production of different chemical constituents during the steaming process. Ginseng saponins, referred to as ginsenosides, are believed to have a ...

The self-heating effect is a severe issue for high-power semiconductor devices, which degrades the electron mobility and saturation velocity, and also affects the device reliability. On applying an ultrafast and high-resolution thermoreflectance imaging technique, the direct self-heating effect and surface temperature increase phenomenon are observed on novel top-gate β-Ga 2 O 3 on insulator field-effect transistors. Here, we demonstrate that by utilizing a higher thermal conductivity sapphire substrate rather than a SiO 2 /Si substrate, the temperature rise above room temperature of β-Ga 2 O 3 on the insulator field-effect transistor can be reduced by a factor of 3 and thereby the self-heating effect is significantly reduced. Both thermoreflectance characterization and simulation verify that the thermal resistance on the sapphire substrate is less than 1/3 of that on the SiO 2 /Si substrate. Therefore, maximum drain current density of 535 mA/mm is achieved on the sapphire substrate, which is 70% higher than that on the SiO 2 /Si substrate due to reduced self-heating. Integration of β-Ga 2 O 3 channel on a higher thermal conductivity substrate opens a new route to address the low thermal conductivity issue of β-Ga 2 O 3 for power electronics applications.

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This paper focuses on the reliability of gravure offset printing and presents a mechanism on how the width of the printed line increases on repeated printings. Of the various printing process parameters, such as the resting times between doctoring, off, and set, printing velocity, printing pressure, and so forth, we investigated the effects of printing velocity, printing pressure, and blanket’s thickness on the reliability of gravure offset printing. As the printing velocity increases, the reliability of gravure offset printing also increases. This is because the actual contact time between ink and blanket decreases, resulting in less solvent absorption into the blanket. Printing pressure does not have much influence on reliability. Even though some change was observed, it was within the range of experimental error. Under sufficient printing pressure, this observation implies that the more important factor as regards the absorption model is time rather than pressure. As the thickness of the blanket increases, the reliability also increases. In the case of a thin blanket, in particular, the reliability of gravure offset printing is sensitive to changes in thickness.

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