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A portable device for studying the effects of fluid flow on degradation properties of biomaterials inside cell incubators.
A portable device was designed and constructed for studying the properties of biomaterials in physiologically relevant fluids under controllable flow conditions that closely simulate fluid flow inside the body. The device can fit entirely inside a cell incubator; and, thus, it can be used directly under standard cell culture conditions. An impedance-driven pump was built in the sterile flow loop to control the flow rates of fluids, which made the device small and portable for easy deployment in the incubator. To demonstrate the device functions, magnesium (Mg) as a representative biodegradable material was tested in the flow device for immersion degradation under flow versus static conditions, while the flow module was placed inside a standard cell incubator. The flow rate was controlled at 0.17 ± 0.06 ml/s for this study; and, the flow rate is adjustable through the controller module outside of incubators for simulating the flow rates in the ranges of blood flow in human artery (0.05 ∼0.43 ml/s) and vein (0.02 ∼0.08 ml/s). Degradation of Mg under flow versus static conditions was characterized by measuring the changes of sample mass and thickness, and Mg2+ ion concentrations in the immersion media. Surface chemistry and morphology of Mg after immersion under flow versus static conditions were compared. The portable impedance-driven flow device is easy to fit inside an incubator and much smaller than a peristaltic pump, providing a valuable solution for studying biomaterials and implants (e.g. vascular or ureteral stents) in body fluids under flow versus static conditions with or without cells
Low-energy electronic recoil in xenon detectors by solar neutrinos
Low-energy electronic recoil caused by solar neutrinos in multi-ton xenon
detectors is an important subject not only because it is a source of the
irreducible background for direct searches of weakly-interacting massive
particles (WIMPs), but also because it provides a viable way to measure the
solar and neutrinos at the precision level of current
standard solar model predictions. In this work we perform
many-body calculations for the structure, photoionization, and
neutrino-ionization of xenon. It is found that the atomic binding effect yields
a sizable suppression to the neutrino-electron scattering cross section at low
recoil energies. Compared with the previous calculation based on the free
electron picture, our calculated event rate of electronic recoil in the same
detector configuration is reduced by about . We present in this paper the
electronic recoil rate spectrum in the energy window of 100 eV - 30 keV with
the standard per ton per year normalization for xenon detectors, and discuss
its implication for low energy solar neutrino detection (as the signal) and
WIMP search (as a source of background).Comment: 12 pages, 3 figure
Enabling Quality Control for Entity Resolution: A Human and Machine Cooperation Framework
Even though many machine algorithms have been proposed for entity resolution,
it remains very challenging to find a solution with quality guarantees. In this
paper, we propose a novel HUman and Machine cOoperation (HUMO) framework for
entity resolution (ER), which divides an ER workload between the machine and
the human. HUMO enables a mechanism for quality control that can flexibly
enforce both precision and recall levels. We introduce the optimization problem
of HUMO, minimizing human cost given a quality requirement, and then present
three optimization approaches: a conservative baseline one purely based on the
monotonicity assumption of precision, a more aggressive one based on sampling
and a hybrid one that can take advantage of the strengths of both previous
approaches. Finally, we demonstrate by extensive experiments on real and
synthetic datasets that HUMO can achieve high-quality results with reasonable
return on investment (ROI) in terms of human cost, and it performs considerably
better than the state-of-the-art alternatives in quality control.Comment: 12 pages, 11 figures. Camera-ready version of the paper submitted to
ICDE 2018, In Proceedings of the 34th IEEE International Conference on Data
Engineering (ICDE 2018
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