There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60meV) which could lead to lasing action based on exciton recombination even above room temperature. Even though research focusing on ZnO goes back many decades, the renewed interest is fueled by availability of high-quality substrates and reports of p-type conduction and ferromagnetic behavior when doped with transitions metals, both of which remain controversial. It is this renewed interest in ZnO which forms the basis of this review. As mentioned already, ZnO is not new to the semiconductor field, with studies of its lattice parameter dating back to 1935 by Bunn [Proc. Phys. Soc. London 47, 836 (1935)], studies of its vibrational properties with Raman scattering in 1966 by Damen et al. [Phys. Rev. 142, 570 (1966)], detailed optical studies in 1954 by Mollwo [Z. Angew. Phys. 6, 257 (1954)], and its growth by chemical-vapor transport in 1970 by Galli and Coker [Appl. Phys. ...

/pdf/a-comprehensive-review-of-zno-materials-and-devices-21a3zjadem.pdf

A comprehensive review of zno materials and devices

Spread Spectrum It’s not just for breakfast anymore! Don't blame me, the title is the work of this month's guest columnist, Steve Bible, N7HPR (n7hpr@tapr.org). While cruising the net recently, I noticed a sudden bump in the number of times Spread Spectrum (SS) techniques were mentioned in the amateur digital areas. While QEX has discussed SS in the past, we haven't touched on it in this forum. Steve was a frequent cogent contributor, so I asked him to give us some background. Steve enlisted in the Navy in 1977 and became a Data Systems Technician, a repairman of shipboard computer systems. In 1985 he was accepted into the Navy’s Enlisted Commissioning Program and attended the University of Utah where he studied computer science. Upon graduation in 1988 he was commissioned an Ensign and entered Nuclear Power School. His subsequent assignment was onboard the USS Georgia, a trident submarine stationed in Bangor, Washington. Today Steve is a Lieutenant and he is completing a master’s degree in computer science at the Naval Postgraduate School in Monterey, California. His areas of interest are digital communications, amateur satellites, VHF/UHF contesting, and QRP. His research area closely follows his interest in amateur radio. His thesis topic is Multihop Packet Radio Routing Protocol Using Dynamic Power Control. Steve is also the AMSAT Area Coordinator for the Monterey Bay area. Here's Steve, I'll have some additional comments at the end.

http://ieeexplore.ieee.org/iel5/5/31355/01457623.pdf

Digital communications

Fundamentals of Plasmonics.- Electromagnetics of Metals.- Surface Plasmon Polaritons at Metal / Insulator Interfaces.- Excitation of Surface Plasmon Polaritons at Planar Interfaces.- Imaging Surface Plasmon Polariton Propagation.- Localized Surface Plasmons.- Electromagnetic Surface Modes at Low Frequencies.- Applications.- Plasmon Waveguides.- Transmission of Radiation Through Apertures and Films.- Enhancement of Emissive Processes and Nonlinearities.- Spectroscopy and Sensing.- Metamaterials and Imaging with Surface Plasmon Polaritons.- Concluding Remarks.

/pdf/plasmonics-fundamentals-and-applications-4syb9877sr.pdf

Plasmonics: Fundamentals and Applications

We report the fixing of a photorefractive grating in KTa1-xNbxO3 . The procedure involves the writing of a photorefractive grating in the cubic phase and the cooling of the sample under an applied field into the rhombohedral phase. We discuss possible mechanisms responsible for the effect.

/pdf/fixing-of-a-photorefractive-grating-in-kta1-xnbxo3-by-28qotzyy7g.pdf

Fixing of a photorefractive grating in KTa1-xNbxO3 by cooling through the ferroelectric phase transition

Transient energy coupling between two coherent beams occurs in dynamic holographic media with local and noninstantaneous responses. The physical origin of the effect is described, and an optical tracking filter based on the effect is demonstrated in a photorefractive Bi12SiO20 crystal.

/pdf/optical-tracking-filter-using-transient-energy-coupling-bbsgrovhy7.pdf

Optical tracking filter using transient energy coupling

Several embodiments of neural processors implemented on a VLSI circuit chip are disclosed, all of which are capable of entering a matrix T into an array of photosensitive devices which may be charge coupled or charge injection devices (CCD or CID). Using CCD's to receive and store the synapses of the matrix T from a spatial light modulator, or other optical means of projecting an array of pixels, semiparallel synchronous operation is achieved. Using CID's, full parallel synchronous operation is achieved. And using phototransistors to receive the array of pixels, full parallel and asynchronous operation is achieved. In the latter case, the source of the pixel matrix must provide the memory necessary for the matrix T. In the other cases, the source of the pixel matrix may be turned off after the matrix T has been entered and stored by the CCD's or CID's.

Parallel optoelectronic neural network processors

We demonstrate a new method to measure high-order polarization mode dispersion (PMD) using the Jones matrix exponential expansion. High-order PMD is characterized by measuring a series of characteristic matrices, which are convenient quantities for analyzing PMD effects in the time-domain. An experimental method is developed to estimate the validity range of the exponential expansion.

/pdf/measurement-of-high-order-polarization-mode-dispersion-cq4jtvxgqx.pdf

Measurement of high-order polarization mode dispersion

A time-dependent analysis of an all-single-mode fiber-optic resonator is presented in which the input field is allowed to exhibit an arbitrary dependence on time. In particular, the transmissivity of the resonator is evaluated for an input field possessing an arbitrary temporal coherence, which allows one to consider the role of the source coherence time as compared with the fiber time delay.

/pdf/time-dependent-analysis-of-a-fiber-optic-passive-loop-48gylrgkmf.pdf

Amnon Yariv

Papers

Fixing of a photorefractive grating in KTa1-xNbxO3 by cooling through the ferroelectric phase transition

Optical tracking filter using transient energy coupling

Parallel optoelectronic neural network processors

Measurement of high-order polarization mode dispersion

Time-dependent analysis of a fiber-optic passive-loop resonator