14 research outputs found
Introduction
May you live in interesting times, runs the legendary Chinese curese. These are interesting times: almost anything can happen except a return to the delicate but enduring balance between two blocs that marked international relations for nearly half a century after World War II. The possibilities include nuclear war, not in the form of the long-feared mutual destruction of the Soviet Union and the United States, but as a last resort in the course of escalating regional conflicts in the Middle East or South Asia. In the aftermath of the 1991 Gulf War, United Nations inspectors found evidence of strong steps toward the production of nuclear weapons in Iraq, a country whose leaders did not hesitate to rain missiles on noncombatant Israel during their struggle to hold Kuwait; the same science is available to many other small, rich despots throughout the world. While the chances that two of the world\u27s largest countries would annihilate each other simultaneously have surely receded, the risk of nuclear war has by no means vanished
Climate and Social Stress: Implications for Security Analysis
Climate change can reasonably be expected to increase the frequency and intensity of a variety of potentially disruptive environmental events--slowly at first, but then more quickly. It is prudent to expect to be surprised by the way in which these events may cascade, or have far-reaching effects. During the coming decade, certain climate-related events will produce consequences that exceed the capacity of the affected societies or global systems to manage; these may have global security implications. Although focused on events outside the United States, Climate and Social Stress: Implications for Security Analysis recommends a range of research and policy actions to create a whole-of-government approach to increasing understanding of complex and contingent connections between climate and security, and to inform choices about adapting to and reducing vulnerability to climate change
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Trends in science and technology relevant to the biological and toxin weapons convention: summary of an international workshop: October 31 to November 3, 2010, Beijing, China
This report offers a summary of the substantive presentations during an international workshop, Trends in Science and Technology Relevant to the Biological and Toxin Weapons Convention, held October 31 - November 3, 2010 at the Institute of Biophysics of the Chinese Academy of Sciences. It is meant to provide scientists and other technical experts with factual information about the range and variety of topics discussed at the workshop, which may be of interest to national governments and non-governmental organizations as they begin to prepare for the 7th Review Conference of the Biological and Toxin Weapons Convention (BWC) in 2011. The Beijing workshop reflected the continuing engagement by national academies international scientific organizations, and individual scientists and engineers in considering the biosecurity implications of developments in the life sciences and assessing trends in science and technology (S&T) relevant to nonproliferation. The workshop provided an opportunity for the scientific community to discuss the implications of relevant developments in S&T for multiple aspects of the BWC. Trends in Science and Technology Relevant to the Biological and Toxin Weapons Convention follows the structure of the plenary sessions at the workshop. It begins with introductory material about the BWC and current examples of the types and modes of science advice available to the BWC and other international nonproliferation and disarmament agreements, in particular the Chemical Weapons Convention (CWC). This report includes only a very brief description of the some of the post-presentation discussions held during the plenary sessions - and does not include an account of the small breakout groups - since these were intended to inform the committee's finding and conclusions and will be reflected in the final report
Structural insights into μ-opioid receptor activation
International audienceActivation of the μ-opioid receptor (μOR) is responsible for the efficacy of the most effective analgesics. To shed light on the structural basis for μOR activation, here we report a 2.1 Å X-ray crystal structure of the murine μOR bound to the morphinan agonist BU72 and a G protein mimetic camelid antibody fragment. The BU72-stabilized changes in the μOR binding pocket are subtle and differ from those observed for agonist-bound structures of the β2-adrenergic receptor (β2AR) and the M2 muscarinic receptor. Comparison with active β2AR reveals a common rearrangement in the packing of three conserved amino acids in the core of the μOR, and molecular dynamics simulations illustrate how the ligand-binding pocket is conformationally linked to this conserved triad. Additionally, an extensive polar network between the ligand-binding pocket and the cytoplasmic domains appears to play a similar role in signal propagation for all three G-protein-coupled receptors
Towards the evolution of vertical-axis wind turbines using supershapes
© 2014, Springer-Verlag Berlin Heidelberg. We have recently presented an initial study of evolutionary algorithms used to design vertical-axis wind turbines (VAWTs) wherein candidate prototypes are evaluated under fan generated wind conditions after being physically instantiated by a 3D printer. That is, unlike other approaches such as computational fluid dynamics simulations, no mathematical formulations are used and no model assumptions are made. However, the representation used significantly restricted the range of morphologies explored. In this paper, we present initial explorations into the use of a simple generative encoding, known as Gielis superformula, that produces a highly flexible 3D shape representation to design VAWT. First, the target-based evolution of 3D artefacts is investigated and subsequently initial design experiments are performed wherein each VAWT candidate is physically instantiated and evaluated under fan generated wind conditions. It is shown possible to produce very closely matching designs of a number of 3D objects through the evolution of supershapes produced by Gielis superformula. Moreover, it is shown possible to use artificial physical evolution to identify novel and increasingly efficient supershape VAWT designs