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Positron emission particle tracking (PEPT) has offered important insights into the internal dynamics of multiphase flows. High precision and frequency measurements of the location of the tracer particle are required to resolve individual eddies at the millimetre scale or smaller. To explore the potential of PEPT to perform these measurements, a model was developed of the Siemens ECAT "EXACT3D" HR++ positron emission tomography (PET) scanner at the PEPT Cape Town facility in South Africa with the software Geant4 Application for Tomographic Emission (GATE) and was used to generate Lagrangian tracks from simulations of moving tracer particles. The model was validated with measurements from both experiment and simulation and was extended to two virtual scenarios inspired by turbulent flows. The location data from the simulation accurately captured linear portions of an oscillating path up to high speeds of 25 m s − 1 ; however, tracking tended to undercut the turning points due to the high tracer acceleration. For a particle moving on a spiral path of decreasing radius, the location data tracked the path above a radius of 2.0 mm with an uncertainty equivalent to the radius of the tracer particle, 300 μ m. Improvements to the measurement are required to track sub-millimetre flow structures, such as the application of PET scanners with higher spatial resolution and upgrades to the sampling processes used in location algorithms. [ABSTRACT FROM AUTHOR]

A sample of isolates from Talaromyces pinophilus (55 isolates) and closely related species (76 isolates) was sequenced at four loci, the data were analyzed using maximum likelihood analysis and the GCPSR. The isolates were subjected to growth studies on the recommended media for description of Talaromyces species. On the basis of the combined data, five new species were segregated out of T. pinophilus and placed in newly described species. The T. pinophilus species complex contains ten species. The three other new species, Talaromyces argentinensis, T. californicus and T. louisianensis were not a part of the T. pinophilus species complex but occurred in Talaromyces sect. Talaromyces. T. argentinensis produces a teleomorphic state and is phylogenetically and morphologically distinct from other Talaromyces species. [ABSTRACT FROM AUTHOR]

Aspergillus is a diverse fungal genus containing many species of great agricultural, biotechnological and medical relevance. Because of the broad use of the genus name in diverse disciplines, and the importance of individual species names in these areas, the taxonomy and nomenclature of Aspergillus should remain stable. A formal proposal to change the generic type from A. glaucus to A. niger was recently published. Here we present arguments against this proposal. We assert that it should be rejected because it will not ensure nomenclatural stability for Aspergillus, and will put the names of several important species, such as A. flavus, A. fumigatus and A. oryzae at risk of being classified in different genera and being lost. [ABSTRACT FROM AUTHOR]

A set of isolates very similar to or potentially conspecific with an unidentified Penicillium isolate NRRL 735, was assembled using a BLAST search of ITS similarity among described (GenBank) and undescribed Penicillium isolates in our laboratories. DNA was amplified from six loci of the assembled isolates and sequenced. Two species in section Cinnamopurpurea are self-compatible sexual species, but the asexual species had polymorphic loci suggestive of sexual reproduction and variation in conidium size suggestive of ploidy level differences typical of heterothallism. Accordingly we use genealogical concordance analysis, a technique valid only in heterothallic organisms, for putatively asexual species. Seven new species were revealed in the analysis and are described here. Extrolite analysis showed that two of the new species, P. colei and P. monsserratidens produce the mycotoxin citreoviridin that has demonstrated pharmacological activity against human lung tumors. These isolates could provide leads in pharmaceutical research. [ABSTRACT FROM AUTHOR]

We describe the first reported case of acute respiratory distress syndrome (ARDS) attributed to Neosartorya udagawae infection. This mold grew rapidly in cultures of multiple respiratory specimens from a previously healthy 43-year-old woman. Neosartorya spp. are a recently recognized cause of invasive disease in immunocompromised patients that can be mistaken for their sexual teleomorph, Aspergillus fumigatus . Because the cultures were sterile, phenotypic identification was not possible. DNA sequencing of ITS, calmodulin and β-tubulin genes supported identification of Neosartorya udagawae . Our case is the first report of ARDS associated with Neosartorya sp. infection and defines a new clinical entity. [ABSTRACT FROM AUTHOR]

The identity of nine clinical isolates recovered from Czech patients and presumptively identified as Aspergillus sp. section Candidi based on colony morphology was revised using sequences of β-tubulin, calmodulin gene sequence, and internal transcribed spacer rDNA. Six isolates were from suspected and proven onychomycosis, one from otitis externa, and two associated with probable invasive aspergillosis. The results showed that one Aspergillus candidus isolate was the cause of otitis externa, and both isolates obtained from sputa of patients with probable invasive aspergillosis were reidentified as A. carneus (sect. Terrei) and A. flavus (sect. Flavi). Three isolates from nail scrapings were identified as A. tritici, a verified agent of nondermatophyte onychomycosis. One isolate from toenail was determined to be A. candidus and the two isolates belonged to a hitherto undescribed species, Aspergillus pragensis sp. nov. This species is well supported by phylogenetic analysis based on β-tubulin and calmodulin gene and is distinguishable from other members of sect. Candidi by red-brown reverse on malt extract agar, slow growth on Czapek–Dox agar and inability to grow at 37°C. A secondary metabolite analysis was also provided with comparison of metabolite spectrum to other species. Section Candidi now encompasses five species for which a dichotomous key based on colony characteristics is provided. All clinical isolates were tested for susceptibilities to selected antifungal agents using the Etest and disc diffusion method. Overall sect. Candidi members are highly susceptible to common antifungals. [ABSTRACT FROM PUBLISHER]

During the course of mold surveys, a set of Talaromyces isolates were obtained that did not fit any described species. Phenotypic examination of these isolates showed that they were similar to T. piceus but differed in some growth characteristics. Multilocus DNA sequence data were obtained for the new isolates and some related species in the broader, more inclusive clade, and the data were analyzed using genealogical concordance. The new isolates are described as Talaromyces columbinus. From analysis of the related species, Penicillium rugulosum var. atricolum is given species status in Talaromyces as T. atricola. Penicillium tardum and P. chrysitis were showed to be synonyms of T. rugulosus. Penicillium scorteum and T. phialosporus were showed to be conspecific and under the rule of priority T. scorteus is the proper name for isolates previously known as T. phialosporus. Talaromyces wortmanii was showed to be distinct from Penicillium concavorugulosum and T. variabilis but the relationship of the latter two species remains unresolved. Examination of ITS sequences from GenBank showed that T. columbinus has previously been reported from human lung infections under the name Penicillium piceum. [ABSTRACT FROM AUTHOR]

Abstract: Coffee (Coffea arabica) plant tissues were surface-sterilized and fungal endophytes isolated using standard techniques, followed by DNA extraction and sequencing of the internal transcribed spacer region (ITS). A total of 843 fungal isolates were recovered and sequenced (Colombia, 267; Hawai''i, 393; Mexico, 109; Puerto Rico, 74) yielding 257 unique ITS genotypes (Colombia, 113; Hawai''i, 126; Mexico, 32; Puerto Rico, 40). The most abundant taxa were Colletotrichum, Fusarium, Penicillium, and Xylariaceae. Overall, 220 genotypes were detected in only one of the countries sampled; only two genotypes were found in all four countries. Endophytes were also isolated from Coffea canephora, Coffea congensis, Coffea liberica, Coffea macrocarpa, Coffea racemosa, and Coffea stenophylla in Hawai''i. The high biodiversity of fungal endophytes in coffee plants may indicate that most of these are “accidental tourists” with no role in the plant, in contrast to endophytes that could be defined as “influential passengers” and whose role in the plant has been elucidated. This study, the most comprehensive analysis of fungal endophytes associated with a single host species, demonstrates that coffee plants serve as a reservoir for a wide variety of fungal endophytes that can be isolated from various plant tissues, including the seed, and illustrates the different fungal communities encountered by C. arabica in different coffee-growing regions of the world. [Copyright &y& Elsevier]

Purpose: This report provides dosimetry information for a new brachytherapy 103Pd source (Model 2335) manufactured by Best Medical International and, through comparisons with data from another published report for the same source, presents a suggested hybrid dataset for clinical applications.Methods and Materials: Dose measurements were made using thermoluminescent dosimeters (TLD), with the 103Pd source in the center of a Virtual Water phantom on a rotating insert, allowing for a number of different possible angles, and 12 TLD cubes (1.0 × 1.0 × 1.0 mm) and 16 TLD rods (1.0 × 1.0 × 3.0 mm) arranged in an outward spiral pattern at distances ranging from 0.5 to 5.0 cm. All measurements are based on the 2000 correction of the National Institute of Standards and Technology 1999 standard.Results: From these measurements, tables are presented for the radial dose function and the anisotropy function. The dose rate constant = 0.71 ± 0.07 cGy h−1 U−1 and the anisotropy constant = 0.96 ± 0.03.Conclusions: The dose rate constant for the hybrid = 0.70 and the anisotropy constant for the hybrid = 0.92, Hybrid tables are presented. [Copyright &y& Elsevier]