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Room temperature diluted ferromagnetic semiconductor is a very promising candidate for spintronics applications. In this work, we present the cobalt ion implanted ZnO epitaxial thin film under controlled annealing temperature to investigate the origin of ferromagnetism in this system. For the as-implanted sample a metallic cobalt cluster was observed. After annealing at 700[degrees]C, the Co atoms were to substitute the Zn sites of the ZnO matrix and exhibited a spontaneous room temperature ferromagnetism. However the XMCD measurements on the annealed samples show the cobalt element is almost paramagnetism at 26 K. The result might indicate oxygen vacancies caused ferromagnetism of intrinsic dilute magnetic semiconductors in the sample of the Co-implanted ZnO. Index Terms--Co-doped ZnO, magnetic circular dichroism (XMCD), magnetic semiconductors.

The performance of an yttrium barium copper oxide superconducting quantum interference device (SQUID) prepared on a magnesium oxide substrate was evaluated. The device, which was coupled to a high temperature superconductor flux transformer, was tested for its current versus voltage, resistance versus temperature and flux versus voltage characteristics. Results show that the performance of the SQUID was enhanced by the incorporation of the flux transformer.

The current transport properties of laser ablated YBa2Cu3O(7-x) films on MgO-bicrystals with the configuration of (001) tilt boundary were investigated. The films' current-voltage and voltage-flux characteristics were measured at different temperatures. The same parameters were determined for a direct current quantum interference device made on a misoriented grain boundary. Results reveal that the critical current density for the two structures decreased exponentially with the (001) tilt angle.

The nonstoichiometry of Li/Cu ionic ratios x and oxygen defect concentrations [delta] in [Li.sub.x][Cu.sub.2][O.sub.2+[delta]] solid solution is studied. The results have shown that Li/Cu and oxygen nonstoichiometry in the crystals are responsible for the varied temperatures of helimagnetic ordering.

This paper is concerned with the problem of passivity analysis and passification for a class of stochastic impulsive memristor-based piecewise linear (PWL) systems with mixed delays and nonlinearity disturbances. Based on the PWL memristor, a PWL system is set up. And some novel sufficient conditions are derived to ensure the passivity/passification performance, such that, for all admissible stochastic disturbances and nonlinearity, the closed-loop stochastic impulsive memristor-based PWL system is passive in the sense of expectation. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate the use of photonic crystal (PC) directional couplers to separate light of wavelengths at 1.31 and 1.55 m. The PC structure consists of InAlGaAs nanorods arranged in hexagonal lattice. The simulation of our device is implemented by the finite-difference time-domain method. The devices are fabricated by e-beam lithography and conventional photolithography. We use the strong inverse method (SIM) of e-beam lithography to make the pattern smoother. The measurement results confirm that 1.31/1.55-m wavelength splitter can be realized in PC structures formed by nanorods. [ABSTRACT FROM PUBLISHER]

Lung cancer is usually diagnosed at an advanced stage, and metastases are present in 40% of patients. The preferential sites of extrapulmonary spread include lymph nodes, liver, brain, adrenal gland, and bone. Small bowel metastasis of lung cancer is a very rare occurrence and may be clinically missed due to the unspecificity of the symptoms. The prognosis is poor. Screening the bowel for metastatic disease cannot be recommended because of its low incidence. However, if a patient with lung cancer presents with gastrointestinal complaints, bowel enema and CT are helpful in diagnosis. Early diagnosis and surgical intervention leads to better palliation and short-term survival. [ABSTRACT FROM AUTHOR]