Penicillium gravinicasei, a new species isolated from cave cheese in Apulia, Italy.

Several species of the genus Penicillium were isolated during a survey of the mycobiota of Apulian cave cheeses ripened in a cave in Gravina di Puglia, Italy. A novel species, Penicillium gravinicasei, is described in Penicillium section Cinnamopurpurea. Its taxonomic novelty was determined using a polyphasic approach, combining phenotypic, molecular (ß-tubulin, calmodulin, ITS and DNA dependent RNA polymerase) DNA sequences and mycotoxin production data. Phylogenetic analyses of the RPB2 data showed that isolates of the novel species form a clade most closely related to Penicillium cinnamopurpureum and P. parvulum with high bootstrap support. The fungus did not produce ochratoxin A, citrinin, patulin, sterigmatocystin or aflatoxin B1 on standard agar media. The novel species had a high growth rate on agar media supplemented with 5% NaCl, and could be distinguished from other Penicillium section Cinnamopurpurea species by phenotypic and molecular characteristics.

Material efficiency studies for a Compton camera designed to measure characteristic prompt gamma rays emitted during proton beam radiotherapy.

Prompt gamma rays emitted from biological tissues during proton irradiation carry dosimetric and spectroscopic information that can assist with treatment verification and provide an indication of the biological response of the irradiated tissues. Compton cameras are capable of determining the origin and energy of gamma rays. However, prompt gamma monitoring during proton therapy requires new Compton camera designs that perform well at the high gamma energies produced when tissues are bombarded with therapeutic protons. In this study we optimize the materials and geometry of a three-stage Compton camera for prompt gamma detection and calculate the theoretical efficiency of such a detector. The materials evaluated in this study include germanium, bismuth germanate (BGO), NaI, xenon, silicon and lanthanum bromide (LaBr(3)). For each material, the dimensions of each detector stage were optimized to produce the maximum number of relevant interactions. These results were used to predict the efficiency of various multi-material cameras. The theoretical detection efficiencies of the most promising multi-material cameras were then calculated for the photons emitted from a tissue-equivalent phantom irradiated by therapeutic proton beams ranging from 50 to 250 MeV. The optimized detector stages had a lateral extent of 10 × 10 cm(2) with the thickness of the initial two stages dependent on the detector material. The thickness of the third stage was fixed at 10 cm regardless of material. The most efficient single-material cameras were composed of germanium (3 cm) and BGO (2.5 cm). These cameras exhibited efficiencies of 1.15 × 10(-4) and 9.58 × 10(-5) per incident proton, respectively. The most efficient multi-material camera design consisted of two initial stages of germanium (3 cm) and a final stage of BGO, resulting in a theoretical efficiency of 1.26 × 10(-4) per incident proton.