15,188 research outputs found
FLORIDA\u27S DOWNTOWNS: THE KEY TO SMART GROWTH, URBAN REVITALIZATION, AND GREEN SPACE PRESERVATION
This article reviews Florida\u27s growth management system, which has spurred suburban development, and its negative impact on Florida\u27s cities. As Florida\u27s governor and legislature have turned their focus to this issue, this article evaluates policy recommendations to limit Florida\u27s suburban sprawl and invigorate its urban centers
Chapter 9 Gene Drive Strategies for Population Replacement
Gene drive systems are selfish genetic elements capable of spreading into a population despite a fitness cost. A variety of these systems have been proposed for spreading disease-refractory genes into mosquito populations, thus reducing their ability to transmit diseases such as malaria and dengue fever to humans. Some have also been proposed for suppressing mosquito populations. We assess the alignment of these systems with design criteria for their safety and efficacy. Systems such as homing endonuclease genes, which manipulate inheritance through DNA cleavage and repair, are highly invasive and well-suited to population suppression efforts. Systems such as Medea, which use combinations of toxins and antidotes to favor their own inheritance, are highly stable and suitable for replacing mosquito populations with disease-refractory varieties. These systems offer much promise for future vector-borne disease control
THE ROLE AND IMPORTANCE OF ACADEMIC FREEDOM IN THE POLICY PROCESS
Academic freedom, Policy process, policy decision-making, policy advice, research, research institute, Political Economy, Teaching/Communication/Extension/Profession,
Electrostatic aggregation of finely-comminuted geological materials
Electrostatic forces are known to have a significant effect on the behavior of finely comminuted particulate material: perhaps the most prevalent expression of this being electrostatic aggregation of particles into relatively coherent clumps. However, the precise role of electrostatic attraction and repulsion in determining the behavior of geological materials (such as volcanic ash and aeolian dust) is poorly understood. Electrostatic aggregation of fine particles is difficult to study on earth either in the geological or laboratory environment principally because the material in an aggregated state remains airborne for such a short period of time. Experiments conducted in the NASA/JSC - KC135 aircraft are discussed. The aircraft experiments are seen as precursors to more elaborate and scientifically more comprehensive Shuttle or Space Station activities
The interaction of colloidal particles with surfaces of solids
Imperial Users onl
Iridium-coated rhenium thrusters by CVD
Operation of spacecraft thrusters at increased temperature reduces propellant requirements. Inasmuch as propellant comprises the bulk of a satellite's mass, even a small percentage reduction makes possible a significant enhancement of the mission in terms of increased payload. Because of its excellent high temperature strength, rhenium is often the structural material of choice. It can be fabricated into free-standing shapes by chemical vapor deposition (CVD) onto an expendable mandrel. What rhenium lacks is oxidation resistance, but this can be provided by a coating of iridium, also by CVD. This paper describes the process used by Ultramet to fabricate 22-N (5-lbf) and, more recently, 445-N (100-lbf) Ir/Re thrusters; characterizes the CVD-deposited materials; and summarizes the materials effects of firing these thrusters. Optimal propellant mixture ratios can be employed because the materials withstand an oxidizing environment up to the meltimg temperature of iridium, 2400 C (4350 F)
Supporting regional growth from the higher education community: the Energy Coast Campus Programme in West Cumbria
West Cumbria is a predominantly rural, but post-industrial region undergoing a transition from one that has been dominated by heavy industry over a 200 year period. The regional economy has latterly been dominated by one of the worldâs largest nuclear technology hubs, which continues to influence the structure of the economy. The region has aspirations to evolve a high technology manufacturing base, with a continued strong role for nuclear, but with a more diversified economy, including an expanded focus on low carbon and renewable energy generation. The region has aspirations to evolve a high technology manufacturing base, with a continued strong role for nuclear, but with a more diversified economy. As part of this strategy, a large investment has been made to build a higher education community in this largely rural area, to support its strategic objectives to promote innovation through applied research, research demonstration, enterprise, business support, skills and training and other transformational actions. Three case studies are described in detail: the Cumbrian Centre for Health Technologies (CaCHeT), the Sustainable Energy Technology Group and the Knowledge Action Network (KAN). The lessons learned are evaluated and presented, with details of future plans
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