SnO(2) nanotubes with controlled diameter and length were synthesized using an electrochemical method at room temperature. The length and wall thickness of the nanotubes increased monotonically with the deposition time and the diameter of the nanotubes was altered by varying the pore size of the scaffolds. Post-annealing at 400 degrees C in dry air significantly improved the crystallinity while...

selective deficiency of immunoglobulin a (iga) is the most frequent primary hypogammaglobulinemia. as some iga-deficient patients have iga antibodies in their plasma which may cause anaphylactic reactions, blood centers usually maintain a list of iga-deficient blood donors to prepare compatible blood components. in this study we determined the incidence of selective iga deficiency (sigad) in no...

in the september and november 2006 issues of nature clinical practice nephrology , two articles regarding living unrelated kidney donor transplantation alluded to the practices in iran. having served in the planning, supervision and implementation of various aspects of health care in iran, including organ transplantation (anh), and as transplant nephrologists who have actively participated in t...

We report a reflectance-based optically detected resonance ~ODR! study of neutral and negatively charged donors in GaAs/AlxGa12xAs quantum-well structures. The intensity of the e1h1(1s) excitonic reflectance feature was modulated by resonant absorption of a monochromatic far-infrared ~FIR! laser beam. An externally applied magnetic field was used to bring the internal transitions among various ...

In analogy to the Wannier equation for localized electronic impurity states in crystalline materials, a wave equation for the envelope of the resonant optical modes of local defects within two-dimensional periodic dielectric structures is derived. In the case of degenerate satellite extrema, this is generalized to a set of coupled Wannier-like equations for a multienvelope system. The localized...

We report a comprehensive theoretical study of structural and electronic properties of substitutional oxygen and zinc contaminations in a model of single wall GaN nanotubes by means of ab initio supercell calculations. Our investigation yields many interesting results. The following ones deserve to be developed. Oxygen forms a shallow donor in the single wall GaN nanotubes as in bulk GaN polyty...

We propose a codoping method of using acceptors and donors simultaneously as a solution to the crucial doping problem, or unipolarity, of wide-band-gap semiconductors which exhibit an asymmetry in their ability to be doped as n-type or p-type. The deliberate codoping of donors is essential for the enhancement of acceptor incorporation, decrease of the binding energy of the acceptor impurity and...

We report on the structural and optical properties of GaN epitaxial layers grown on GH-Sic. We employed the sublimation sandwich method to grow single crystal layers at high growth rates with free carrier concentrations of 2 X 1Oi7 cmw3. Very narrow x-ray diffraction peaks of the GaN (0002) plane are obtained indicating the high quality of this system. These tidings are directly reflected in th...

Background: Nowadays, gamete and embryo donation is applied as effective process in treatment infertility problems. In order to participate in the process of donation, donors should complete an extensive questionnaire that details their personal and family medical history. Included in this questionnaire should be a detailed sexual history, substance abuse history, history of family disease, and...

The influence of irradiation with white light on the permeability at 77 K is investigated on p-type yttrium iron garnet single crystals with Pb impurity. Theexistence of an irreversible photo-magnetic effect and photo-accelerated disaccommodation is demonstrated in p-type YIG. These effects are explained by a modified two center model in which Fe4+ plays an important role.