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Leptographiumspecies provide an ideal model to test the applications of a PCR microcoding system for differentiating species of other genera of ascomycetes. Leptographiumspecies are closely related and share similar gross morphology. Probes designed for a PhyloChip for Leptographiumhave been transferred and tested as primers for PCR diagnostic against Leptographiumspecies. The primers were combined with complementary universal primers to identify known and suspected undescribed species of Leptographium. The primer set was optimized for 56 species, including the three varieties of L. wageneri, then blind-tested against 10 random DNA samples. The protocols established in this study successfully identified species from the blind test as well as eight previously undescribed isolates of Leptographium. The undescribed isolates were identified as new species of Leptographiumwith the aid of the microcoding PCR identification system established in this study. The primers that were positive for each undescribed isolate were used to determine close relatives of these species and some of their biological characteristics. The transfer of oligonucleotides from a micro-array platform to a PCR diagnostic was successful, and the identification system is robust for both known and unknown species of Leptographium.

The taxonomy of Armillariain southern South America has received little attention since the work of Singer and others. In this study we examine the morphological traits and cultural features for taxa representing the lineages revealed based on molecular phylogeny, and we link them to previously described taxa based on morphology. Lineages I–IV were identified as Armillaria novaezelandiae, A. montagnei, A. umbrinobrunneacomb. nov. and A. sparreirespectively. They could be differentiated morphologically based on dimension, features of the epicutis, annulus, stipe, hymenophoral trama and flavor and characteristics in culture. Furthermore there was no evidence of host preference for the species recognized. This is the first study integrating the phylogeny and morphology of Armillariaspecies from Patagonia, and it provides a foundation for future research on these fungi in South America.

Dielectric charges and charge stability were compared in different dielectrics formed on SiC by different processing techniques. The concentration and transient behavior of the interface and trapped charges were investigated. Strong hysteresis and flat-band voltage drift under applied bias were observed in some of the samples. They are attributed to the trapping of the charge injected in the dielectrics. Differences in charge injection, charge trapping, and capture/emission of carriers by interface traps were pronounced for the investigated SiO2 and Si3N4 dielectrics.

The heat equation, for both steady and unsteady situations, is considered when the material parameters are spherically symmetric functions of position. Explicit separated solutions are derived when the material parameters are exponential functions; the radial part of these solutions is given in terms of confluent hypergeometric functions or Whittaker functions. In the steady case, explicit solutions are found when the conductivity k(r)= exp(−βrq), where β and qare parameters with q>0. The behaviour near the tip of a spherically-graded cone is also investigated.

In this paper, we consider the inverse problem for the Laplace equation in two-dimensions which requires the determination of the location, size and shape of an unknown, or partially unknown, portion n z of the boundary z of a solution domain z R 2 from additional Cauchy data on the remaining portion of the boundary o = z m n . This problem arises in the study of quantitative non-destructive evaluation of corrosion in materials in which boundary measurements of currents and voltages are used to determine the material loss caused by corrosion. This inverse problem is approached using the boundary element method (BEM) in conjunction with the Tikhonov first-order regularization procedure. The choice of the regularization parameter is based on an L-curve type criterion although, alternatively one may use the discrepancy principle. Several examples which involve noisy Cauchy input data are thoroughly investigated showing that the numerical method produces a stable approximate solution which is also convergent to the exact solution as the data errors tend to zero.

The potential energy, dipole, quadrupole and octopole moments and dipole polarisabilities have been calculated at CASSCF level for the ground X1Σ+state of the PO+molecular ion as a function of internuclear distance. Most of the electrical properties have not previously been calculated and show rapid variations around 5a.u. due to a perturbation. The calculated vibrational frequency of 1410.4cm−1and the integrated IR absorption intensity of 984cm2mol−1should lead towards the first observation of the vibrational spectrum.

The problem of three-dimensional potential flow past a thin rigid screen is reduced to a hypersingular boundary integral equation. This equation is then projected onto a flat reference screen, which is taken to be a circular disc. Solutions are obtained for screens that are axisymmetric perturbations from the disc, so that the screen is rippled concentrically. The added mass is calculated for axisymmetric flow past such screens, correct to second order.

The potential energy curves, dipole, quadrupole, octopole and hexadecapole moment functions of the ground X 1Σ+state of NO+have been calculated at Hartree-Fock, CASSCF, MR-CI and MP2 levels using a [8s6p3d] basis set. In addition, dipole polarisabilities have also been calculated at the HF and MP2 level. Results for the quadrupole moment and dipole polarisabilities compare favourably with recent experimental results from the spectroscopy of NO Rydberg states.