This article briefly reviews the causes and impacts of the massive eastern Japan earthquake and tsunami of 11 March 2011, and comments on the response measures taken by Japan to cope with this devastating disaster. Mass losses occurred mostly because the intensity of the quake and the induced tsunami exceeded local coping capacity. Particularly, the nuclear power plant crisis triggered by the tsunami significantly increased the short-and long-term impacts of the disaster. While the coping capacity Japanese society built after the 1995 Hanshin-Awaji great earthquake tremendously mitigated the damages, there is room for improvement despite Japan's great efforts in this disaster. Investigating the tsunami preparedness of the coastal nuclear power plants is an issue of paramount importance. In response to future large-scale disasters, there is an urgent need for a highly collaborative framework based on which all available resources could be mobilized; a mutual assistance and rescue system against catastrophes among regions and countries on the basis of international humanitarian aid; and further in-depth research on the multi-hazard and disaster-chain phenomenon in large-scale disasters and corresponding governance approaches.

PandaX is a large upgradable liquid-xenon detector system that can be used for both direct dark-matter detection and 136 Xe double-beta decay search. It is located in the Jinping Deep-Underground Laboratory in Sichuan, China. The detector operates in dual-phase mode, allowing detection of both prompt scintillation, and ionization charge through proportional scintillation. The central time projection chamber will be staged, with the first stage accommodating a target mass of about 120 kg. In stage II, the target mass will be increased to about 0.5 ton. In the final stage, the detector can be upgraded to a multi-ton target mass. In this paper a detailed description of the stage-I detector design and performance results established during the commissioning phase is presented.

The year 2015 is the 25th annum of the international disaster and risk reduction proposed by the United Nations. Disaster risk reduction (DRR) has achieved significant progress worldwide. The goals of disaster risk reduction, climate change adaptation, and sustainable development have become the joint responsibility of all countries in their economic, societal, cultural, political, and ecological construction activities. In the past 25 years, UNISDR together with national governments, scientific community, NGOs, entrepreneur groups, media and various relevant regional organizations is gaining effective results in alleviating human being's casualties, property losses, and damages to resources and environment caused by natural hazards on the world and is earning a great reputation at every stratum of society as well. Nevertheless, data released by related UN organizations indicate that natural disaster and disaster risk are still on the rise globally. Some nations and regions are still extremely vulnerable to large-scale disasters, although significant progress has been made in DRR actions. Natural disaster risk reduction is still a long haul ahead. FoundationsThe global hot spots project jointly finished by the World Bank and Columbia University (the USA) is the first ever cartography of major natural disaster risks at the global scale (Dilley et al. 2005). The UNISDR Global Assessment Report on Disaster Risk Reduction (GAR) inspired this Atlas (UN-ISDR 2009, 2011 All faculties and students of BNU on the disaster risk science and the international experts who participated in the IHDP/Future Earth-Integrated Risk Governance and "111 Project", as well as all the personnel involved in these two projects, throughout ten years of preparation, planning, and action, were organized to compile this atlas, aiming to reflect the spatial patterns of the main natural disaster risk all around the world. This atlas provides scientific evidence for taking effective measures of world natural disaster risk reduction by demonstrating the spatial variation from the following three spatial scales for the main natural disaster risk on the world: the grid unit (1°× 1°, 0.75°× 0.75°, 0.5°× 0.5°, 0.25°× 0.25°, 0.1°× 0.1°or 1 km × 1 km), the comparable geographic unit (about 448,334 km 2 per unit), and the national or regional unit (245 nations and regions). International Scientific and Technological CooperationClose cooperation with worldwide scientific institutions lays the scientific foundation of this Atlas. Scientific BasisThe World Atlas of Natural Disaster Risk attempts to reveal the spatial pattern of the risks of natural disaster which are mainly caused by physical hazards in the world with multiple perspectives of natural environment, exposure, disaster loss, and disaster risk with the framework of Regional Disaster System Theory (Shi 1991(Shi , 1996(Shi , 2002(Shi , 2005(Shi , 2009. It emphasizes the spatial-temporal pattern of worldwide natural disasters from the perspective of individual disasters and integrated disasters, in...

We have utilized a computational model of the expansion of a microbubble in a liquid-filled flexible tube to investigate the potential for acoustic vaporization of perfluorocarbon droplets to damage blood vessels during a novel gas embolotherapy technique for the potential treatment of tumors. This model uses a fixed grid, multi-domain, interface tracking, direct numerical simulation method that treats all interfaces and boundaries as sharp discontinuities for high accuracy. In the current work, we examined effects of initial bubble size on the flows and wall stresses that result from droplet vaporization. The remaining dimensionless parameters that govern the system response (Reynolds, Weber, and Strouhal numbers, initial bubble pressure, and wall stiffness and tension) were selected to model an arteriole. The results for a flexible tube are significantly different from those for a rigid tube. Two major flow regimes occur due to the combined effect of bubble and tube deformation: in flow at the tube ends and out flow near the bubble surface. The flexibility of the tube largely dissipates the extreme pressure that develops in the rigid tube model. Both the magnitude and the overall expansion time of the rapidly changing pressure are greatly reduced in the flexible tube. Smaller initial bubble diameters, relative to the vessel diameter, result in lower wall stresses. This study indicates that wall flexibility can significantly influence the wall stresses that result from acoustic vaporization of intravascular perfluorocarbon droplets, and suggests that acoustic activation of droplets in larger, more flexible vessels may be less likely to damage or rupture vessels than activation in smaller and stiffer vessels.

In this article, we recall the United Nations’ 30-year journey in disaster risk reduction strategy and framework, review the latest progress and key scientific and technological questions related to the United Nations disaster risk reduction initiatives, and summarize the framework and contents of disaster risk science research. The object of disaster risk science research is the “disaster system” consisting of hazard, the geographical environment, and exposed units, with features of regionality, interconnectedness, coupling, and complexity. Environmental stability, hazard threat, and socioeconomic vulnerability together determine the way that disasters are formed, establish the spatial extent of disaster impact, and generate the scale of losses. In the formation of a disaster, a conducive environment is the prerequisite, a hazard is the necessary condition, and socioeconomic exposure is the sufficient condition. The geographical environment affects local hazard intensity and therefore can change the pattern of loss distribution. Regional multi-hazard, disaster chain, and disaster compound could induce complex impacts, amplifying or attenuating hazard intensity and changing the scope of affected areas. In the light of research progress, particularly in the context of China, we propose a three-layer disaster risk science disciplinary structure, which contains three pillars (disaster science, disaster technology, and disaster governance), nine core areas, and 27 research fields. Based on these elements, we discuss the frontiers in disaster risk science research.