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Teleomorph: Venturia inaequalis Cooke (Wint.); Kingdom Fungi; Phylum Ascomycota; Subphylum Euascomycota; Class Dothideomycetes; Family Venturiaceae; genus Venturia; species inaequalis. Anamorph: Fusicladium pomi (Fr.) Lind or Spilocaea pomi (Fr.). LIFE CYCLE: V. inaequalis is a hemibiotroph and overwinters as pseudothecia (sexual fruiting bodies) following a phase of saprobic growth in fallen leaf tissues. The primary inoculum consists of ascospores, which germinate and penetrate the cuticle. Stromata are formed above the epidermal cells but do not penetrate them. Cell wall-degrading enzymes are only produced late in the infection cycle, raising the as yet unanswered question as to how V. inaequalis gains nutrients from the host. Conidia (secondary inoculum) arise from the upper surface of the stromata, and are produced throughout the growing season, initiating multiple rounds of infection. VENTURIA INAEQUALIS AS A MODEL PATHOGEN OF A WOODY HOST: V. inaequalis can be cultured and is amenable to crossing in vitro, enabling map-based cloning strategies. It can be transformed readily, and functional analyses can be conducted by gene silencing. Expressed sequence tag collections are available to aid in gene identification. These will be complemented by the whole genome sequence, which, in turn, will contribute to the comparative analysis of different races of V. inaequalis and plant pathogens within the Dothideomycetes.

Deposition of tin-doped–indium-oxide (ITO) on unheated substrates via low energy processes such as electron-beam deposition can result in the formation of amorphous films. The amorphous-to-crystalline transformation was studied in this system using in situ resistivity, time resolved reflectivity, glancing incidence angle x-ray diffraction, and transmission electron microscopy. The resistivity of 180 nm thick In2O3(9.9 wt. %SnO2) was monitored during isothermal anneals at 125, 135, 145, and 165 °C. The dependence of the resistance on the volume fraction of crystalline phase was established using glancing incidence angle x-ray diffraction and a general two phase resistivity model for this system was developed. These studies show that, upon annealing, as-deposited amorphous ITO undergoes both a structural relaxation and crystallization. Structural relaxation of the amorphous material includes local ordering that increases the ionized vacancy concentration which, in turn, increases the carrier density in the material. Kinetic growth parameters were extracted from the data, which reveal that the relaxation of the amorphous structure occurs via a process that obeys a first order reaction rate law, while crystallization occurs via classical nucleation and growth with a growth mode parameter that is consistent with two- to three-dimensional transformation geometry. Both the relaxation and crystallization processes have an activation energy of approximately 1.3±0.2 eV. Time resolved reflectivity analysis of the electron beam deposited ITO reveals that there is a sharp and monotonic decrease in reflectivity during the anneal of the sample which is associated with the amorphous relaxation process.

The authors report on the fabrication and characterization of thin film transistors that use sputter deposited amorphous indium zinc oxide both for the channel and source-drain metallizations in a gate-down configuration. The channel and source-drain layers were deposited from a single In2O3–10wt%ZnO ceramic target using dc magnetron sputtering onto an unheated substrate. The carrier densities in the channel (2.1×1017∕cm3) and source/drain regions (3.3×1020∕cm3) were adjusted by changing the reactive oxygen content in the sputter chamber during deposition. The resulting transistors operate as depletion mode n-channel field effect devices with saturation mobility of 20cm2∕Vs and on/off current ratio of 108.