Thermal Energy Generation in the Earth

We show that a recently introduced class of electromagnetic composite particles can explain some discrepancies in observations involving heat and helium released from the earth. Energy release during the formation of the composites and subsequent nuclear reactions involving the composites are described that can quantitatively account for the discrepancies and are expected to have implications in other areas of geophysics, for example, a new picture of heat production and volcanism in the earth is presented.Comment: 11 pages, 7 figure

Electromagnetic Structure Resonances in Inhomogeneous Plasma Layers

Laser-light absorption and radiation forces are investigated for weakly collisional (_/__1), rigid, two-step plasma profiles in planar and spherical geometry. For the first step near critical density, the second step above critical, and appropriate step lengths, we find strong absorption even for weakly collisional plasmas. We show, however, that the radiation forces may not permit such profiles to persist in realistic, dynamic situations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86119/1/PhysRevLett.40.30-RKO.pd

Laser-driven micro-explosive bonding of aluminium films to copper and silicon

Laser explosive microfabrication was used to bond micrometre-thick aluminium films to both copper and silicon substrates. Bonding was observed in both systems for laser intensities greater than about 1 × 10 9 W cm −2 and resulted in contiguous, uniform films when performed in a rough vacuum of 25 to 70 millitorr. At intensities greater than 9 × 109 W cm-2 the transferred films were generally black in colour due to oxidation in the aluminium-on-copper shots and due to substrate vaporization in the aluminium-on-silicon shots. SEM examination of the bond interfaces indicated mixing of film and substrate through wave formation and possibly through liquid-phase mixing due to thermal conduction of the laser pulse. Tape adhesion testing of the laser-bonded films showed a significant increase in adhesion over vapour-deposited films in both Al-Cu and Al-Si. Vapour-deposited films were easily removed in their entirety by a single tape pull while metallic portions of the laser-bonded films resisted removal by the tape in all but two tests. The enhanced adhesion evident in the laser-bonded films was a result of intermixing observed at the film-substrate interface.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44689/1/10853_2005_Article_BF01115786.pd

Tissue-engineered valved conduits in the pulmonary circulation

AbstractObjective: Bioprosthetic and mechanical valves and valved conduits are unable to grow, repair, or remodel. In an attempt to overcome these shortcomings, we have evaluated the feasibility of creating 3-leaflet, valved, pulmonary conduits from autologous ovine vascular cells and biodegradable polymers with tissue-engineering techniques. Methods: Endothelial cells and vascular medial cells were harvested from ovine carotid arteries. Composite scaffolds of polyglycolic acid and polyhydroxyoctanoates were formed into a conduit, and 3 leaflets (polyhydroxyoctanoates) were sewn into the conduit. These constructs were seeded with autologous medial cells on 4 consecutive days and coated once with autologous endothelial cells. Thirty-one days (±3 days) after cell harvesting, 8 seeded and 1 unseeded control constructs were implanted to replace the pulmonary valve and main pulmonary artery on cardiopulmonary bypass. No postoperative anticoagulation was given. Valve function was assessed by means of echocardiography. The constructs were explanted after 1, 2, 4, 6, 8, 12, 16, and 24 weeks and evaluated macroscopically, histologically, and biochemically. Results: Postoperative echocardiography of the seeded constructs demonstrated no thrombus formation with mild, nonprogressive, valvular regurgitation up to 24 weeks after implantation. Histologic examination showed organized and viable tissue without thrombus. Biochemical assays revealed increasing cellular and extracellular matrix contents. The unseeded construct developed thrombus formation on all 3 leaflets after 4 weeks. Conclusion: This experimental study showed that valved conduits constructed from autologous cells and biodegradable matrix can function in the pulmonary circulation. The progressive cellular and extracellular matrix formation indicates that the remodeling of the tissue-engineered structure continues for at least 6 months. (J Thorac Cardiovasc Surg 2000;119:732-40

Outsourcing Governance: States and the Politics of a ‘Global Value Chain World’

Politics, and by extension states, are marginal in debates about the genesis, evolution and functioning of the GVC-based global economy. We contend here that the core complexity of state agency and state power needs to be much more carefully understood in GVC and related debates, as a basis on which the governance of the evolving GVC world can be properly theorised as revolving around the inseparability of economic and political power. We advance a framework for understanding the role of politics and states in the construction and maintenance of a GVC world, using a three-fold typology of facilitative, regulatory and distributive forms of governance, and propose a notion of ‘outsourcing governance’ as an attempt to capture the ways in which states purposefully, through active political agency, have engaged in a process of delegating a variety of governance functions and authority to private actors. Our overarching argument is normative: ‘outsourced governance’ of the form we currently observe is associated with regressive distributional outcomes, and is antithetical to an inclusive and sustainable global economy

The Association of Arsenic Exposure and Metabolism With Type 1 and Type 2 Diabetes in Youth: The SEARCH Case-Control Study

Little is known about arsenic and diabetes in youth. We examined the association of arsenic with type 1 and type 2 diabetes in the SEARCH for Diabetes in Youth Case-Control (SEARCH-CC) study. Because one-carbon metabolism can influence arsenic metabolism, we also evaluated the potential interaction of folate and vitamin B12 with arsenic metabolism on the odds of diabetes

Substrate protein folds while it is bound to the ATP-independent chaperone Spy

Chaperones assist the folding of many proteins in the cell. While the most well studied chaperones use cycles of ATP binding and hydrolysis to assist protein folding, a number of chaperones have been identified that promote protein folding in the absence of highenergy cofactors. Precisely how ATP-independent chaperones accomplish this feat is unclear. Here we have characterized the kinetic mechanism of substrate folding by the small, ATP-independent chaperone, Spy. Spy rapidly associates with its substrate, Immunity protein 7 (Im7), eliminating its potential for aggregation. Remarkably, Spy then allows Im7 to fully fold into its native state while remaining bound to the surface of the chaperone. These results establish a potentially widespread mechanism whereby ATP-independent chaperones can assist in protein refolding. They also provide compelling evidence that substrate proteins can fold while continuously bound to a chaperone

Sequential Analysis of Trans-SNARE Formation in Intracellular Membrane Fusion

SM proteins stabilize cis-SNARE complexes leading to a specific preferred topology for trans-SNARE formation