Background: Here we describe superparamagnetic relaxometry (SPMR), a technology that utilizes highly sensitive magnetic sensors and superparamagnetic nanoparticles for cancer detection. Using SPMR, we sensitively and specifically detect nanoparticles conjugated to biomarkers for various types of cancer. SPMR offers high contrast in vivo, as there is no superparamagnetic background, and bones and tissue are transparent to the magnetic fields. Methods: In SPMR measurements, a brief magnetizing pulse is used to align superparamagnetic nanoparticles of a discrete size. Following the pulse, an array of superconducting quantum interference detectors (SQUID) sensors detect the decaying magnetization field. NP size is chosen so that, when bound, the induced field decays in seconds. They are functionalized with specific biomarkers and incubated with cancer cells in vitro to determine specificity and cell binding. For in vivo experiments, functionalized

We study the interplanetary conditions during the occurrence of the most intense solar energetic particle (SEP) event observed by the MESSENGER spacecraft during the rising phase of solar cycle 24. Elevated electron intensities at MESSENGER (at 0.33 AU from the Sun) resulted from the confinement of energetic particles by two CME-driven shocks. This scenario is consistent with that proposed by Kallenrode and Cliver [3] to explain the most intense SEP events of a solar cycle. In analogy to the rogue ocean waves having unusually large amplitudes due to the superposition of two wave fields, these events were referred to as rogue SEP events. We compare the interplanetary conditions in the most intense event at MESSENGER with those observed in other rogue SEP events.

A Stirling cycle micro-refrigeration system composed of arrays of silicon MEMS cooling elements has been designed and evaluated thermodynamically. The cooling elements are each 5 mm-long, 2.25 mm-wide, have a thickness of 300 μm, and are fabricated in a stacked array on a silicon wafer. A 0.5 mm-long regenerator is placed between the compression (hot side) and expansion (cold side) diaphragms. The diaphragms are 2.25 mm circles driven electrostatically. Helium is the working fluid, pressurized at 2 bar and sealed in the system. Under operating conditions, the hot and cold diaphragms oscillate sinusoidally 90° out of phase such that heat is extracted to the expansion space and released from the compression space. The bulk silicon substrate on which the device is grown is etched with “zipping” shaped chambers under the diaphragms. The silicon enables efficient heat transfer between the gas and heat source/sink as well as reduces the dead volume of the system, thus enhancing the cooling capacity. In addition, the “zipping” shaped substrates reduce the voltage required to actuate the diaphragms. An array of vertical silicon pillars in the regenerator serves as a thermal capacitor transferring heat to and from the working gas during a cycle. In operation, the push-pull motion of the diaphragm makes a 300 μm stroke and actuates at a frequency of 2 kHz. Parametric study of the design shows the effects of phase lag, swept volume ratio between the hot space and cold space, and dead volume ratio on cooling capacity. At TH = 313.15 K and TC = 288.15 K and assuming a perfect regenerator, the thermodynamic optimization analysis gives a heat extraction rate of 0.22 W per element and cooling capacity of 30 W/cm2 for the stacked system. Evaluation of the stacked system shows that the COP will reach 6.3 if the expansion work from the cold side is recovered electrostatically and used to drive the hot side diaphragm.

Boeing has developed a 50 kW DC reversible solid oxide fuel cell (RSOFC) system that uses sunlight and sea water to generate and store energy with no logistical tail. In this system, renewable energy is sent to the system operating in electrolysis mode to produce H 2 . The H 2 is stored and then used in the system's fuel cell mode to provide power to the grid. As part of this program, Boeing has developed a H 2 storage and compression system, power distribution system, and master controller to interface with the fuel cell subsystem developed by Sunfire. The system was shipped to Pearl Harbor as part of a 6 month field demonstration supported by the Naval Facilities Engineering Command and Expeditionary Warfare Center (NAVFAC). This paper will discuss the demonstration of the RSOFC system in island microgrid environments and how it helps to address a logistic free hydrogen economy in remote areas.

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