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

A mathematical analysis is presented for dye laser amplifier chains used to amplify cw mode-locked dye laser pulses up to the gigawatt regime. The model permits a discussion of the important aspects of the problem such as gain saturation, pulse shaping, and the optimization of pumping efficiencies. Experimentally, an amplifier chain has been demonstrated which is simple in design and operation without sacrificing high performance. A frequency doubled Q-switched Nd:YAG oscillator alone is used to longitudinally pump three identical Brewster cells with the same flowing dye solution in each. The amplifier boosts the output of a synchronously mode-locked dye laser to obtain ~0.5 mJ ≾ 1 psec pulses over a ~400 A bandwidth. These pulses are suitable for efficient Raman shifting, frequency mixing, and continuum generation to vastly extend the spectral range of the system. Some experimental results are presented to support the mathematical model.

/pdf/analysis-and-performance-of-a-picosecond-dye-laser-amplifier-4e02y15l2m.pdf

Analysis And Performance Of A Picosecond Dye Laser Amplifier Chain

Absorption bands in the wave‐number range of 3525–3470 cm−1 have been observed in K1−yLiyTa1−xNbxO3 (KLTN) doped crystals except in crystals doped with Cu and V. These absorption bands are attributed to the O–H vibration band. The hydrogen concentration in KLTN doped crystal is controllable either by doping or by heat treatment. The activation energy of hydrogen ion migration is between 0.6 and 0.7 eV in KLTN doped crystals. The [H +] ion is identified as responsible for fixing (screening) the holographically produced electronic grating.

Near infrared absorption and dark conductivity of k1-yliyta1-xnbxo3 crystal

We investigate the modal losses and field distributions of different order transverse modes supported by the photonic crystal Bragg structure using a transfer matrix method. We find that only the fundamental transverse mode has a single-lobed near field and far field and there exists a trade-off between ensuring lasing in the fundamental transverse mode and reducing the threshold. Employing these design principles, we experimentally demonstrate a large-area, edge-emitting, and single-mode semiconductor photonic crystal Bragg laser with a single-lobed, diffraction-limited far field under continuous wave condition.

/pdf/spatial-modal-control-of-two-dimensional-photonic-crystal-2kt3d81d29.pdf

Spatial modal control of two-dimensional photonic crystal Bragg lasers

Light diffracted from a grating output coupler in a Ti‐diffused LiNbO3 waveguide is scanned electro‐optically. Using a coupling length of 2.5 mm in our arrangement we have demonstrated a scanning capability of one resolved spot per 3 V/μm applied field.

/pdf/electro-optic-scanning-of-light-coupled-from-a-corrugated-14owylxirj.pdf

Electro‐optic scanning of light coupled from a corrugated LiNbO3 waveguide

The transverse‐modal behavior of a lateral injection gain‐guided laser [the transverse junction strip (TJS) laser] excited by a short (70 ps) electrical pulse is investigated experimentally and theoretically. It is predicted theoretically and observed experimentally that the transverse mode strongly depends on the excitation pulse amplitude and the dc bias current (which is set below threshold). This dependence is found to be due to transient lateral carrier diffusion at the lasing junction.

/pdf/transverse-modal-behavior-of-a-transverse-junction-stripe-ottwublndu.pdf

Amnon Yariv

Papers

Analysis And Performance Of A Picosecond Dye Laser Amplifier Chain

Near infrared absorption and dark conductivity of k1-yliyta1-xnbxo3 crystal

Spatial modal control of two-dimensional photonic crystal Bragg lasers

Electro‐optic scanning of light coupled from a corrugated LiNbO3 waveguide

Transverse‐modal behavior of a transverse junction stripe laser excited by a short electrical pulse