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Aerial photos and Google Earth images of the Laramie Basin in Wyoming were used to measure size, and calculate species-specific growth rates and ages for 304 rings comprising eight species of fairy ring forming fungi. Estimated age was used to explore establishment, dynamics and persistence in relation to historic precipitation and drought data. Size of fairy rings ranged from 4 to 272 meters, and age from 15 to 522 years. 90% of all rings were younger than 80 years. Species-specific growth rates varied from 0.131 to 0.364 meters per year. All fairy ring species became established over a wide range of precipitation, although most rings established during years with 25–30 centimeters of precipitation. Little correlation was observed between establishment and precipitation patterns for some fungi, however others exhibited a significant relationship between year of establishment and both August precipitation and the Palmer Modified Drought Index. Expansion of one large ring was followed for 75 years. These data demonstrate that turnover in fairy rings is quite high and that fairy ring fungi can establish over a wide range of moisture levels. [ABSTRACT FROM AUTHOR]

Few studies of tripartite mycoheterotrophic systems have examined ecological specificity across broad geographic ranges or addressed autotrophic host specificity. Pterospora andromedea was selected as an ideal candidate to examine ecological specificity of a mycoheterotrophic system as it is widely distributed, has been shown to have high levels of symbiont specificity with Rhizopogon subgenus Amylopogon , and is found with several autotrophic hosts. Pairs of P. andromedea + Rhizopogon spp. samples were co-collected across North America and were sequenced using trnL and ITS, respectively. Bayesian phylogenetic reconstructions between the co-collected taxa were used to examine ecological specificity, and for subsequent tests for autotroph specificity. P. andromedea lineages exhibited both high specificity and relaxed specificity for fungal symbionts and autotrophic hosts across the geographic landscape under allopatric and sympatric conditions. This strong evidence for geographic mosaics of specificity in mycoheterotrophic systems is an important future consideration in determining the evolutionary ecology of mycoheterotrophs. [ABSTRACT FROM AUTHOR]

Abstract: Mycoheterotrophic plants are nonphotosynthetic and must form a relationship with a mutualistic fungus and an autotrophic host to acquire carbon. In this study, identity of fungal associates of Pterospora andromedea in the south-central Rocky Mountains was determined. Although P. andromedea has been found to associate with at least three Rhizopogon species groups throughout its range in North America, it was found to exclusively associate with the Rhizopogon salebrosus species group in the Rocky Mountains. In addition, the genetic structure of R. salebrosus was examined. The data support the presence of two genetic lineages within the R. salebrosus species group that exhibit strong biogeographic distribution linked to historic conifer association with Pinus contorta and Pinus ponderosa. A zone of secondary contact between the two lineages was also identified along with a number of putative hybrids. [Copyright &y& Elsevier]

Fairy rings are conspicuous features of the Laramie Basin of southeastern Wyoming. Ten fairy ring sites chosen for intensive study were located using a small plane and 415 whole and partial fairy rings were georeferenced and ground-truthed. Fairy ring forming fungi were identified using a combination of taxonomy and ITS fungal barcode sequence comparisons. Precipitation, vegetation, soil type, elevation, slope, and slope aspect were queried using GIS. Eight fairy ring forming species were identified from the sites, including three unknown species, and two taxa not previously reported to form fairy rings. Most fairy rings occurred in drier mixed-grass prairie vegetation, whereas a small percentage occurred in mesic shrub dominated riparian vegetation. Most fungal species exhibited preferences for elevation and slope aspect, and rings were scarce on east facing slopes. The identity and autecology of individual fairy ring fungi and importance of environmental variables to fairy ring biology is discussed. [ABSTRACT FROM AUTHOR]

We synthesized BCNO compounds and investigated how the synthesis conditions impact i) BCNO formation, their chemistry and degree of crystallinity, and ii) BN formation from BCNO and its structural ordering. Heating boric acid (H 3 BO 3 ) and melamine (C 3 H 6 N 6 ) mixture yields intermediate amorphous BCNO compound. Increasing the synthesis temperature, and H 3 BO 3 to C 3 H 6 N 6 ratio promote BN formation and its structural ordering. We propose a possible reaction mechanism for BN formation from H 3 BO 3 and C 3 H 6 N 6 mixture and we explain the observations based on thermodynamic and kinetic considerations. An increase in synthesis temperature promotes BN formation since the reactions are endothermic. An increase in H 3 BO 3 to C 3 H 6 N 6 ratio promotes BN formation since theoretical BN formation temperature decreases with the above ratio. Furthermore, it enhances material transfer and mobility of the BN layer by forming B 2 O 3 phase. We also propose a processing-structure correlation map that can help determining experimental conditions for single-phase amorphous BCNO synthesis. [ABSTRACT FROM AUTHOR]

Emulsion detonation synthesis (EDS) is a recently developed process to synthesize nano-sized ceramics based on detonation of two water-in-oil emulsions. The process produces high pressure and temperature along with fast cooling, thus providing ideal environment for metastable phase formation. Here we applied the process for the first time on hexagonal boron nitride (h-BN). Characterization studies demonstrated the formation of metastable explosion BN phase (e-BN) with grain sizes of 10–20 nm embedded in h-BN matrix. These findings support the potential use of EDS a novel and promising pathway for the synthesis of e-BN and other metastable BN phases. [ABSTRACT FROM AUTHOR]

Cubic boron nitride (c-BN) has superior hardness and strength as compared to other ceramics that are commonly used as abrasives and in cutting tool applications. Cubic BN powders are generally produced under high pressures, usually greater than 10 GPa. Here, we report on the synthesis of nanocrystalline c-BN from metastable precursors without high external pressures using a novel plasma spray processing technique. Transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS) measurements indicate that the initial metastable precursor particles are amorphous and comprised of boron, carbon, nitrogen and oxygen with weak interatomic bonding that may easily undergo phase transformations during plasma spraying. Postmortem X-ray diffraction and TEM analysis of plasma spray deposits reveal the formation of crystalline phases of BN, and high-resolution TEM observations demonstrate that c-BN can be induced during the plasma spray process with the addition of appropriate catalysts. These observations point to a novel pathway for facilitating the transition from a low-density amorphous state to the high-density cubic BN phase. [ABSTRACT FROM AUTHOR]

Abstract: Cantharellus pleurotoides sp. nov. (Cantharellaceae, Cantharellales, Basidiomycota) is described from the Pakaraima Mountains of Guyana, occurring in rainforests dominated by ectomycorrhizal Dicymbe spp. (Caesalpiniaceae). This fungus is singular among Cantharellus species described worldwide in possessing a pleurotoid basidioma. Macromorphological, micromorphological, and habitat data are provided for the new species. [Copyright &y& Elsevier]

Abstract: Gymnomyces xerophilus sp. nov., a sequestrate species in the Russulaceae, is characterized and described morphologically as a new species from Quercus-dominated woodlands in California. ITS sequences recovered from healthy, ectomycorrhizal roots of Quercus douglasii and Q. wislizeni matched those of G. xerophilus basidiomata, confirming the ectomycorrhizal status of this fungus. Phylogenetic analysis of the ITS region places G. xerophilus in a clade with both agaricoid (Russula in the section Polychromae) and sequestrate (Gymnomyces, Cystangium) relatives. We include a dichotomous key to the species of Gymnomyces associated with Quercus. [Copyright &y& Elsevier]

The Florida Keys coral reef ecosystem supports multimillion-dollar commercial and recreational fisheries. The ecological effects caused by fishing gear that is lost when cut or broken after snagging on the bottom is a growing concern to managers and scientists. Few data exist, however, to assess the impacts of lost fishing gear to benthic organisms and habitat structure. In this study, 63 offshore coral reef and hard-bottom sites were surveyed during 2001 to quantify the impacts of lost fishing gear to coral reef sessile invertebrates. Lost hook-and-line fishing gear accounted for 87% of all debris (N=298 incidences) encountered and was responsible for 84% of the 321 documented impacts to sponges and benthic cnidarians, predominantly consisting of tissue abrasion causing partial individual or colony mortality. Branching gorgonians (Octocorallia) were the most frequently affected (56%), followed by milleporid hydrocorals (19%) and sponges (13%). Factors affecting the impacts of lost fishing gear include sessile invertebrate density, the density of lost fishing gear, and gear length. While lost hook-and-line fishing gear is ubiquitous in the Florida Keys, less than 0.2% of the available milleporid hydrocorals, stony corals, and gorgonians in the habitats studied are adversely affected in terms of colony abrasions and partial mortality. [Copyright &y& Elsevier]