Dual Energy CTによる高吸収結節の検出能の改善 : 結節を含む模擬肝臓を使用したファントム研究

広島大学(Hiroshima University)博士(医学)Doctor of Philosophy in Medical Sciencedoctora

Improved Detectability of Hyper-Dense Nodules Using Dual-Energy Computed Tomography Scanning: Phantom Study Using Simulated Liver Harboring Nodules

The purpose of this study was to evaluate the detectability of hyper-dense nodules using dual-energy computed tomography (DECT) in a phantom. Arterial-phase hepatic dynamic computed tomography (CT) was conducted on small, medium, and large liver-simulating phantoms harboring simulated hypervascular tumors. We acquired 150 single-energy CT (SECT) and 150 DECT scans and measured the contrast-to-noise ratio (CNR) of the nodules. Alternative free response receiver observer characteristic (AFROC) curves of five radiologists’ readings of the SECT and DECT scans were compared to assess detectability of the hyper-dense nodules. For all phantoms, the CNR of nodules measured using DECT was significantly higher than that by using SECT (p < 0.001, all). In the AFROC study, DECT showed a significantly larger area under the curve than that with SECT (0.778 vs 0.499, p = 0.012). Detectability of high-density nodules was better with DECT scans than with SECT scans

SOME WAYS TO INCREASE CIVIL SOCIETY PARTICIPATION IN ENSURING POLITICAL SECURITY IN MONGOLIA

Political security is about the organizational stability of states i.e. The systems of government and the ideologies that give governments, and states, their legitimacy. Political sector threats target the organizational stability and sovereignty of the state. Although they may originate from (or be aimed at) the military, societal, economic, environmental and/or the political sectors, to be classified as political threats, they must threaten the organizational stability of the state without using massive military, identification, economic, or environmental means. Their objectives range from pressuring governments to behave in a certain manner on policy matters to overthrowing governments or provoking separatism and preparation for war.1 The values and nature of the civil society are aimed at protecting the interests of the country and citizens, improving the quality of life, and ensuring sustainable development. The main issue of political security is the protection of the political interests of the country and its citizens, a set of measures, the governmental and non-governmental organizations it is aimed at the sustainable development of the country and the improvement of the quality of people's life as well as the form of governance, state management mechanisms and political forces, state, leaders of state and all of these are aimed at creating a political system. When we are considering the participation of civil society in security activities, firstly political security is considered in the framework of this research