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Biomedical subjects

John Oakey

Publications and source records attributed to John Oakey.

5 recordsLinked to original sources

Biosolids--a fuel or a waste? An integrated appraisal of five co-combustion scenarios with policy analysis.

An integrated appraisal of five technology scenarios for the co-combustion of biosolids in the UK energy and waste management policy context is presented. Co-combustion scenarios with coal, municipal solid waste, wood, and for cement manufacture were subject to thermodynamic and materials flow modeling and evaluated by 19 stakeholder representatives. All scenarios provided a net energy gain (0.58-5.0 kWh/kg dry solids), having accounted for the energy required for transportation and sludge drying. Co-combustion within the power generation and industrial (e.g., cement) sectors is most readily implemented but provides poor water utility control, and it suffers from poor public perception. Co-combustion with wastes or biomass appears more sustainable but requires greater investment and presents significant risks to water utilities. Incongruities within current energy and waste management policy are discussed and conclusions for improved understanding are drawn.

Bioelectric Energy Sources↗

Microfluidic sorting system based on optical waveguide integration and diode laser bar trapping.

Effective methods for manipulating, isolating and sorting cells and particles are essential for the development of microfluidic-based life science research and diagnostic platforms. We demonstrate an integrated optical platform for cell and particle sorting in microfluidic structures. Fluorescent-dyed particles are excited using an integrated optical waveguide network within micro-channels. A diode-bar optical trapping scheme guides the particles across the waveguide/micro-channel structures and selectively sorts particles based upon their fluorescent signature. This integrated detection and separation approach streamlines microfluidic cell sorting and minimizes the optical and feedback complexity commonly associated with extant platforms.

Cell Culture Techniques↗

Microfluidic control using colloidal devices.

By manipulating colloidal microspheres within customized channels, we have created micrometer-scale fluid pumps and particulate valves. We describe two positive-displacement designs, a gear and a peristaltic pump, both of which are about the size of a human red blood cell. Two colloidal valve designs are also demonstrated, one actuated and one passive, for the direction of cells or small particles. The use of colloids as both valves and pumps will allow device integration at a density far beyond what is currently achievable by other approaches and may provide a link between fluid manipulation at the macro- and nanoscale.

Colloids↗

Laminar-flow-based separations at the microscale.

The natural separation maintained by microfluidic flows is employed as the basis of a particle/cell sorting device. This method of separating particulate suspensions exploits the inherent laminar nature of microscale fluid dynamics and incorporates applied fields and image cytometry to enable sorting based upon any visually identifiable difference between colloid-sized cells or particles. This technique may be used to easily isolate, separate, sort, or enrich virtually any suspension of microscale biological or colloidal particles within a microfluidic system. The entire footprint of the device described here is less than 0.01 mm(2), allowing it to be readily incorporated within highly integrated micro total analysis systems (microTAS).

Cell Separation↗