305 research outputs found
Debris-free in-air laser dicing for multi-layer MEMS by perforated internal transformation and thermally-induced crack propagation
MEMS 2008, Tucson, AZ, USA, January 13-17, 200
Radiation Reaction by Massive Particles and Its Non-Analytic Behavior
We derive a massive analog of the ALD (Abraham, Lorentz and Dirac) equation,
i.e., the equation of motion of a relativistic charged particle with a
radiation reaction term induced by emissions of massive fields. We show that
the radiation reaction term has a non-analytic behavior as a function of the
mass M of the radiation field and both expansions with respect of M and 1/M are
generally invalid. Hence the massive ALD equation cannot be written as a local
equation with derivative expansions. We especially investigate the radiation
reaction in three specific motions, uniform acceleration, a circular motion and
a scattering process.Comment: 22 pages, 5 figure
Metamaterial-Inspired Quad-Band Notch Filter for LTE Band Receivers and WPT Applications
A new compact quad-band notch filter (QBNF) based on the extended composite right and left-handed transmission line (E-CRLH TL) has been presented. As known, E-CRLH TL behaves like a quad-band structure. A microstrip TL which is loaded with an open-ended ECRLH TL is presented as a QBNF. Four unwanted frequencies were used in a dual-band LTE receiver as four notch frequencies which must be eliminated (0.9 GHz, 1.3 GHz, 2.55 GHz, and 3.35 GHz). Also, this QBNF can be applied to simultaneous wireless power and data transfer (SWPDT) system to isolate the wireless power circuit from the data communication circuit. A design technique for the proposed QBNF is presented and its performance is validated using full-wave simulation results and theoretical analysis. The main advantage of this design is an overall rejection greater than 20dB at selected unwanted frequencies. Good agreements between the fullwave simulation and equivalent circuit model results have been achieved which verified the effectiveness of the proposed circuit model. The proposed QBNF is designed on an FR-4 substrate and the dimension of the proposed QBNF is 20 * 22 mm
Development of x-ray emission computed tomography for ICF research
Copyright 1990 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Review of Scientific Instruments, 61(10), 2763-2785, 1990 and may be found at http://dx.doi.org/10.1063/1.114183
Chemoattractant receptors activate, recruit and capture G proteins for wide range chemotaxis
The wide range sensing of extracellular signals is a common feature of various sensory cells. Eukaryotic chemotactic cells driven by GPCRs and their cognate G proteins are one example. This system endows the cells directional motility towards their destination over long distances. There are several mechanisms to achieve the long dynamic range, including negative regulation of the receptors upon ligand interaction and spatial regulation of G proteins, as we found recently. However, these mechanisms are insufficient to explain the 105-fold range of chemotaxis seen in Dictyostelium. Here, we reveal that the receptor-mediated activation, recruitment, and capturing of G proteins mediate chemotactic signaling at the lower, middle and higher concentration ranges, respectively. These multiple mechanisms of G protein dynamics can successfully cover distinct ranges of ligand concentrations, resulting in seamless and broad chemotaxis. Furthermore, single-molecule imaging analysis showed that the activated Gα subunit forms an unconventional complex with the agonist-bound receptor. This complex formation of GPCR-Gα increased the membrane-binding time of individual Gα molecules and therefore resulted in the local accumulation of Gα. Our findings provide an additional chemotactic dynamic range mechanism in which multiple G protein dynamics positively contribute to the production of gradient information
10-kJ PW Laser for the FIREX-I Program
A 10-kJ PW laser (LFEX) is under construction for the
FIREX-I program. This paper reports a design overview of LFEX, the
technological development of a large-aperture arrayed amplifier with
modified four-pass architecture, wavefront correction, a large-aperture
Faraday rotator with a superconducting magnet, a new pulse compressor
arrangement, and focus control
Planar shock wave generated by uniform irradiation from two overlapped partially coherent laser beams
Copyright 2001 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics, 89(5), 2571-2575, 2001 and may be found at http://dx.doi.org/10.1063/1.134218
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