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The effects of interface polarization charge on the photovoltaic characteristics of GaN/InGaN solar cells have been analyzed in detail using 2D drift-diffusion simulations. The polarization charge at the GaN/InGaN interface creates an electric field that forces carriers generated by light to drift in opposite direction needed for efficient collection and substantially reduces the short circuit current (I{sub sc}) and open circuit voltage (V{sub oc}). The polarization charge plays an important role in the photovoltaic properties of InGaN solar cells comparable to that of defects. For small interface charge, the potential barrier could increase the V{sub oc}. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

In this work, based on the advanced drift and diffusion model with commercial software, the Crosslight APSYS, InP/InGaAs separate absorption, grading, charge and multiplication APDs for high bit-rate operation have been modeled. Basic physical quantities such as band diagram, optical absorption and generation are calculated. Performance characteristics such as dark- and photo-current, photoresponsivity, multiplication gain, breakdown voltage, excess noise, frequency response and bandwidth etc., are simulated. The modeling results are selectively presented, analyzed, and some results are compared with experiments. Device design optimization issues are further discussed with respect to the applicable features of the Crosslight APSYS within the framework of the drift-diffusion theory. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In this work, two-dimensional simulation has been performed on the triple-junction (TJ) GaInP/GaAs/Ge solar cell devices based on the Crosslight APSYS with improved tunnel junction model. The APSYS simulator solves several interwoven equations including the basic Poisson's equation, and drift-diffusion current equations for electrons and holes. Basic physical quantities like band diagrams, optical absorption and generation are calculated. The simulated IV characteristics and offset voltage agree well with the published experimental results for TJ GaInP/GaAs/Ge solar cell device. The quantum efficiency spectra have also been computed. Possible design optimization issues to enhance the quantum efficiency have also been discussed with respect to some applicable features of Crosslight APSYS. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In this work we use the PROCOM sofware to model Mg doped GaN film growth by MOCVD. The 2/3D conservation equations of mass, energy, momentum and species are solved by the nonsymmetric conjugate gradient method with block preconditioning (H. C. Elman, Preconditioned conjugate gradient methods for nonsymmetric systems of linear equations (Yale University Research Report, 1981) [5]). A kinetics model with gas/surface adduct formation has been incorporated with detailed Mg dopant reaction mechanism. We reproduced broad doping profiles caused by memory effects and verified that the formation of (NH3)2-MgCp2 and NH3-MgCp2 adducts play an important role in p-doping of GaN and related Group III nitrides. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We extended the theory by Henry (J. Lightwave Technol. LT-4, 288 (1986) [1]) to accurately treat the coupling of spontaneous emission noise with microcavity modes. The Green's function method is employed to solve the inhomogeneous wave equation including a Langevin force Fω which accounts for spontaneous emission by carriers at angular frequency ω. The optical wave equation is coupled with the self-consistent calculations of the material spontaneous emission rate of quantum well/dot using envelope wavefunction method. Finally the carrier transport equations are solved within the framework of 2D/3D drift-diffusion model implemented in the Crosslight Software package APSYS (Crosslight APSYS User's Manuals, Copyright © Crosslight Software Inc. (version 2005. 11) [2]). (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Background: Local anesthetic containing epinephrine is commonly used in many operations for the main purpose of hemostasis. A randomized, controlled, prospective clinical trial was designed to find out hemodynamic changes after local infiltration of different concentrations and/or different dosages of epinephrine during functional endoscopic sinus surgery (FESS) under general anesthesia. Methods: One hundred and eight adult patients undergoing elective FESS under general anesthesia were randomly allocated into four groups. Group I received 2% lidocaine 2 ml with epinephrine (5 µg/ml); group II received 1% lidocaine 4 ml with epinephrine (2.5 µg/ml); group III received 1% lidocaine 4 ml with epinephrine (5 µg/ml); and group IV received 1% lidocaine 4 ml for local infiltration. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were monitored continuously in the radial artery and recorded in 6 min: before infiltration (baseline), 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, and 6 min after local infiltration. The lowest blood pressure (BP) in this period was also recorded. Results: Significant hemodynamic changes, particularly a decrease in BP (P 0.05). Conclusion: Local infiltration of low-dose epinephrine causes temporary significant hemodynamic changes particularly a marked decrease in BP during FESS under general anesthesia.

Minimal inhibitory concentrations (MICs) of amorolfine for 52 pathogenic yeasts or yeast-like organisms, filamentous and dimorphic fungi represented by 955 isolates were determined in agar dilution tests. Amorolfine has a broad antifungal spectrum, but unfortunately this drug is so far only available for topical use.

Results and discussion: Analysis of the g.+6723G>A mutation in East Friesian revealed 29 homozygotes for the mutant allele (A/A), 41 heterozygotes (A/G) and 9 animals homozygous for the wild-type allele (G/G). The genotypic frequencies are in agreement with Hardy-Weinberg equilibrium (v = 0.94; d.f. = 1). Detection of g.+6723A within the East Friesian, grouped it with the Texel, White Faced Suffolk, Lincoln and Charollais as a breed known to segregate this Myostatin mutation. The estimated frequency of g.+6723A within the East Friesian was 0.63, which is lower than for Texel, where it is near fixation. This may reflect the emphasis put on milk production by East Friesian breeders, but it also suggests that selection could quickly produce highly muscled animals. Association analysis to determine the effect of the mutation was not performed because of the absence of phenotypic records; however, breeders report the presence of lines within the East Friesian that display enhanced muscularity. Previous work reported that g.+6723A was found on a single haplotype defined by alleles at two flanking microsatellites (BM81124 allele 218 and BULGE20 allele 141). To determine if g.+6723A in East Friesian is accompanied by the same haplotype, the two microsatellites were genotyped in ten homozygous (A/A) sheep. The results revealed that seven of the animals (70%) were homozygous for the same combination of microsatellite alleles observed in the Texel. This strongly suggests a common origin for the mutation, because the alternative scenario that the mutation has arisen independently within each breed would predict that the allele would be accompanied by different haplotypes. The close geographical proximity of the breeds and anecdotal information suggest a shared origin, which explains why the allele appears to be identical by descent in both East Friesian and Texel sheep.

Summary. A rare case of pyoderma gangraenosum caused by Rhizopus arrhizus is reported. The patient, a 50-year-old male farmer, was admitted to hospital complaining of gangrening and festering of the right upper arm with severe pain for nearly 2 months. A lesion was found on the inside of right upper arm. The central skin part of the lesion became black dry gangrenous, the periphery was deeply ulcerated with yellow-green pus. The necrotic crust, biceps, triceps and vessels inherited a histopathologically proven fungal infection. The fungus isolated was identified as Rhizopus arrhizus. The infection was successfully treated with itraconazole. Zusammenfassung. Es wird von einem seltenen Fall eines Pyoderma gangraenosum, verursacht von Rhizopus arrhizus, berichtet. Der 50-jahrige Patient, ein Landwirt, wurde in das Krankenhaus eingewiesen mit seit 2 Monaten bestehenden Beschwerden einer Gangran und Eiterungen mit starken Schmerzen im rechten Oberarm. Eine Lasion zeigte sich an der Innenseite des rechten Oberarms. Die Haut im Zentrum der Gangran war schwarz und trocken, die Peripherie war ulzeriert und sonderte gelbgrunen Eiter ab. In der nekrotischen Kruste sowie an Bizeps, Trizeps und Getfasen konnte histopathologisch eine Pilzinfektion nachgewiesen werden. Das Isolat wurde als Rhizopus arrhizus identifiziert. Die Infektion heilte unter Itraconazolbehandlung ab.