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Introduction Erythropoietin has revolutionised the treatment of the anaemia of chronic renal failure. Recombinant human erythropoietin is now recognised as safe and effective treatment for the severe anaemia of end [...]

Academic physicians and pediatric subspecialists may be less likely than other physicians to provide HIV screening to children at-risk for transfusion-acquired infection. Researchers surveyed 574 physicians to characterize their attitudes and behaviors about testing at-risk patients for transfusion-related HIV infection. Physicians cited common barriers to HIV screening that included: concern about the patient's response to possible HIV exposure, feeling uncomfortable counseling patients, and lack of time for proper counseling. Practitioners were significantly more likely than academic physicians to ask patients about HIV risk factors, to encourage HIV testing among at-risk patients, and to provide HIV screening. Subspecialist pediatricians were less likely to screen for HIV or to feel comfortable providing patient counseling compared to other physicians.

Self-organized 3D nanostructured architectures including quasi-ordered concentric hexagonal structures generated during the growth of single crystalline n-GaN substrates by hydride vapor phase epitaxy (HVPE) are reported. The study of as-grown samples by using Kelvin Probe Force Microscopy shows that the formation of self-organized architectures can be attributed to fine modulation of doping related to the spatial distribution of impurities. The specific features of nanostructured architectures involved have been brought to light by using electrochemical and photoelectrochemical etching techniques which are highly sensitive to local doping. The analysis of the results shows that the formation of self-organized spatial architectures in the process of HVPE is caused by the generation of V-pits and their subsequent overgrowth accompanied by the growth in variable direction. It is demonstrated for the first time that the electrical and luminescence properties of HVPE-grown GaN are spatially modulated throughout, including islands between overgrown V-pit regions. The dependence of doping upon growth direction is confirmed by the micro-cathodoluminescence characterization of HVPE-grown pencil-like microcrystals exposing various crystallographic planes along the tip. These results are indicative of new possibilities for defect engineering in gallium nitride and for three-dimensional spatial nanostructuring of this important electronic material by controlling the growth direction.

NOW IS A TIME TO REFLECT, ten years since our democracy gave birth. Cedric Mayson ('Faith, Struggle and Kairos,' Autumn 2003) writes eloquently on the magic midnight moments, crafted over [...]

Cathodoluminescence and photoluminecsence are investigated in titanium dioxide nanotubes (TiO2 NTs) produced in an ethylene glycol based electrolyte with the variation of the temperature of the electrolyte which allows the control of the inner diameter of nanotubes. The crystal structure of the produced nanotubes is controlled by the post-anodization thermal treatment. A new fast and cost-effective method for the fabrication of anatase TiO2 NTs is proposed. The cathodoluminescence spectra and panchromatic images from the produced TiO2 nanotubes suggest the formation of resonator modes in clusters of nanotubes. The enhancement of the ultraviolet near-bandgap or the green photoluminescence is demonstrated by means of coating the anatase TiO2 nanotubes with thin Ag or Au films, respectively.

We report on fabrication of ultra-thin GaN membranes of nanometer scale thickness, by using the concept of surface charge lithography based on low-energy ion treatment of the sample surface with subsequent photoelectrochemical etching. The membranes prove to be transparent to both electrons and UV radiation, emit mainly yellow cathodoluminescence, and exhibit electrical conductivity. Successful fabrication of nanometer-thin membranes opens unique possibilities for exploration of two dimensional GaN-based structures predicted to be ferromagnetic with defect-induced half-metallic configuration which is of peculiar importance for spintronics applications.

A myeloid chloroleukemia in the rat has been studied and developed into an assay for the screening of antileukemic compounds. A series of phosphoramide derivatives have been found to be effective against this leukemia, and comparative studies on their activity have been made. These compounds appear to be as effective as TEM and can be administered at higher dosage levels. All of the compounds produced a prompt remission of the disease.