Search

Pylaiella littoralis is a brown alga with a cosmopolitan distribution. A free-living form of the alga fouls the beaches of Nahant, Massachusetts (USA). The amphipod Gammarus tigrinus is found within the floating drifts of algae. Gut contents confirmed that G. tigrinus consumed P. littoralis. Significantly, culture studies revealed that ingested P. littoralis survives and grows from fecal pellets produced by G. tigrinus. Also, inefficient grazing produced vegetative fragments that grew and survived. δ13C values for the amphipods and P. littoralis averaged −17.4 ‰ and −17.7 ‰, respectively, suggesting that G. tigrinus acquires most of its carbon from P. littoralis. [ABSTRACT FROM AUTHOR]

Premise: Mycoheterotrophic plants rely on fungi to obtain their carbon requirements. Recent experiments demonstrated the presence of endophytic bacteria associated with mycoheterotrophs. Although mycoheterotrophs show high specificity for their fungal partners, it is not known whether they also show high specificity for associated bacteria or whether the bacteria have a definite function in the symbiosis. Methods: Two 16S rRNA sequencing experiments were designed to explore endophytic microbial community composition and function in root ball fractions of the mycoheterotroph Pterospora andromedea (Ericaceae), and rhizosphere soil and control soil 5 m away from each plant. One experiment compared microbial assemblages in fractions of six plants to those in rhizosphere and control soil samples. Another experiment documented bacterial endophyte diversity in root balls of 97 plants from across North America. Results: Soil samples were similar in bacterial community structure but were significantly more diverse and less consistently structured than were bacterial communities within root balls. The proportion of endophytic bacterial species varied slightly but not their community composition despite differences in P. andromedea lineage, geography, conifer species, and fungi. Predictive metagenomic profiling of the endophytes in P. andromedea‐only root ball fractions showed many of the bacterial endophytes likely function in N‐metabolism and N‐fixation. Conclusions: Our results document a consistent and largely invariant community of endophytic bacteria in P. andromedea across biotic and abiotic environmental conditions at a continental scale. It is unknown what role these bacteria may play in the quad‐partite symbiotic network centered on P. andromedea; however, the predictive metagenomic profiling suggests a possible function in N‐metabolism or N‐fixation. Discovery of a ubiquitous community of endophytic bacteria with a putative function centered on N‐metabolism or N‐fixation could have a previously unrecognized impact on understanding of mycoheterotroph ecophysiology. [ABSTRACT FROM AUTHOR]

Amanita ballerina and A. brunneitoxicaria spp. nov. are introduced from Thailand. Amanita fuligineoides is also reported for the first time from Thailand, increasing the known distribution of this taxon. Together, those findings support our view that many taxa are yet to be discovered in the region. While both morphological characters and a multiple-gene phylogeny clearly place A. brunneitoxicaria and A. fuligineoides in sect. Phalloideae (Fr.) Quél., the placement of A. ballerina is problematic. On the one hand, the morphology of A. ballerina shows clear affinities with stirps Limbatula of sect. Lepidella. On the other hand, in a multiple-gene phylogeny including taxa of all sections in subg. Lepidella, A. ballerina and two other species, including A. zangii, form a well-supported clade sister to the Phalloideae sensu Bas 1969, which include the lethal “death caps” and “destroying angels”. Together, the A. ballerina-A. zangii clade and the Phalloideae sensu Bas 1969 also form a well-supported clade. We therefore screened for two of the most notorious toxins by HPLC-MS analysis of methanolic extracts from the basidiomata. Interestingly, neither α-amanitin nor phalloidin was found in A. ballerina, whereas Amanita fuligineoides was confirmed to contain both α-amanitin and phalloidin, and A. brunneitoxicaria contained only α-amanitin. Together with unique morphological characteristics, the position in the phylogeny indicates that A. ballerina is either an important link in the evolution of the deadly Amanita sect. Phalloideae species, or a member of a new section also including A. zangii. [ABSTRACT FROM AUTHOR]

Inhibition of acetylcholinesterase (AChE) after nerve agent exposure induces status epilepticus (SE), which causes brain damage or death. The development of countermeasures appropriate for the pediatric population requires testing of anticonvulsant treatments in immature animals. In the present study, exposure of 21-day-old (P21) rats to different doses of soman, followed by probit analysis, produced an LD 50 of 62 μg/kg. The onset of behaviorally-observed SE was accompanied by a dramatic decrease in brain AChE activity; rats who did not develop SE had significantly less reduction of AChE activity in the basolateral amygdala than rats who developed SE. Atropine sulfate (ATS) at 2 mg/kg, administered 20 min after soman exposure (1.2 × LD 50 ), terminated seizures. ATS at 0.5 mg/kg, given along with an oxime within 1 min after exposure, allowed testing of anticonvulsants at delayed time-points. The AMPA/GluK1 receptor antagonist LY293558, or the specific GluK1 antagonist UBP302, administered 1 h post-exposure, terminated SE. There were no degenerating neurons in soman-exposed P21 rats, but both the amygdala and the hippocampus were smaller than in control rats at 30 and 90 days post-exposure; this pathology was not present in rats treated with LY293558. Behavioral deficits present at 30 days post-exposure, were also prevented by LY293558 treatment. Thus, in immature animals, a single injection of atropine is sufficient to halt nerve agent-induced seizures, if administered timely. Testing anticonvulsants at delayed time-points requires early administration of ATS at a low dose, sufficient to counteract only peripheral toxicity. LY293558 administered 1 h post-exposure, prevents brain pathology and behavioral deficits. [ABSTRACT FROM AUTHOR]

The Russulales is one of 12 major lineages recently elucidated by molecular sequence data in the homobasidiomycetes. The order is morphologically most diverse, containing a remarkable variety of sporophore forms including resupinate, discoid, effused-reflexed, clavarioid, pileate, or gasteroid and hymenophore configurations from smooth, poroid, hydnoid, lamellate, to labyrinthoid. Functionally these fungi are primarily saprotrophs but others are ectomycorrhizal, root parasites and insect symbionts. A phylogenetic analysis of the nuclear 5.8S, ITS2 and large-subunit rDNA genes comprises the best information to date on relationships of taxa within the Russulales. Two large sister groups encompassing 11-13 major clades have been recovered within the Russulales. Based on molecular and morphological data 12 families and approximately 80 genera have been identified, although placement of many taxa has not yet been determined. The two clades containing ectomycorrhizal taxa, corresponding to the Russulaceae and the Albatrellaceae, represent the greatest diversity of sporophore morphologies. The primarily pileate lamellate family Russulaceae is nested with resupinate species and also contains pileate sequestrate, gasteroid annulate and pleurotoid forms. Albatrellaceae similarly contains resupinate poroid, pileate poroid and pileate labyrinthoid sporophores. Presence of gloeoplerous hyphae containing fluid that typically stains black in sulfoaldehyde compounds is a synapomorphy for the Russulales. Amyloid reactions in spore or hyphal walls that occur frequently throughout the Russulales often are perceived as an obvious synapomorphy but are inconsistent. Approaches including sequencing functional genes, analysis of gene expression and biochemical analysis across the entire order are needed. [ABSTRACT FROM AUTHOR]

Summary • The spatial mapping of genets from sporocarps allows determination of the primary modes of reproduction of ectomycorrhizal fungi. The goals of this research were to determine the relative size, density, and persistence of genets of Russula brevipes , a late successional basidiomycete, in mature stands of lodgepole pine ( Pinus contorta ) and Sitka spruce ( Picea sitchensis ). • Sporocarps were mapped and genets were identified using species-specific hypervariable microsatellite markers. • Most of the sporocarps sampled in clumped aggregations were the same genet and occupied areas less than 3 m. The largest distance measured between two sporocarps of the same genet was 18 m. In local populations of R. brevipes associated with Sitka spruce, genets were comprised of largely related individuals, whereas in lodgepole pine, most genets appeared unrelated. • High genotypic diversity in Sitka spruce stands suggests frequent mating and recombination between local inhabitants from primary establishment of basidiospores. In lodgepole pine, fewer, unrelated genotypes of R. brevipes indicates that multiple sources of colonization arose from infrequent, long distance spore dispersal events. [ABSTRACT FROM AUTHOR]

NEURO.tv is a new educational project that seeks to bring advanced concepts in neuroscience to the general public. We film one-hour discussions with leading neuroscientists, philosophers, and psychologists who have had significant impact on our current understanding of brain function, and we publish these discussions on YouTube, iTunes, and other social media outlets. Here, we explain the motivations behind this new program. [ABSTRACT FROM AUTHOR]

Recent declines in coral populations along the Florida reef tract have prompted the establishment of coral restoration programs which raise coral species, such as the threatened Acropora cervicornis, in nurseries ready for outplanting. Large numbers of nursery-reared coral colonies have been outplanted along the Florida reef tract in recent years, yet few studies have characterized benthic habitats that are considered optimal for colony survival. In 2016, we surveyed 23 A. cervicornis restoration sites, located at six different reefs in the upper Florida Keys. We examined the condition of the outplanted corals and quantified the benthic assemblages adjacent to the outplanted coral colonies. We found that where A. cervicornis survived for more than 1 year, the substrate significantly supported less brown macroalgae of the genus Dictyota than at sites where A. cervicornis had died. Coral survival was highest at sites with less than 15% Dictyota cover. These results suggest that the habitat conditions that supported Dictyota spp. were not conducive to A. cervicornis growth and survival. Restoration practitioners should avoid attaching nursery-raised corals to substrate with Dictyota spp. cover greater than 15%. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about threats to coral reefs that must be addressed simultaneously to reverse coral decline.

The first species of Rhizopogon subgenus Amylopogon identified from eastern North America is described here as Rhizopogon kretzerae Grubisha, Dowie, & Mill. sp. nov. In nature, R. kretzerae has been identified only from DNA sequences of the nuclear ribosomal internal transcribed spacer region (ITS) from mycorrhizal roots of Pinus strobus L. and Pterospora andromedea Nutt. Phylogenetic analyses and nucleotide divergence estimates of Rhizopogon ITS sequences from Pterospora roots from Quebec, Michigan, New York, and New Hampshire combined with ITS sequences of Rhizopogon subgenus Amylopogon species type collections suggest R. kretzerae is a sister-group to Rhizopogon salebrosus A.H. Sm. An absence of sharedmutations, two informative sequence gaps, and 12 fixed nucleotide differences differentiate R. kretzerae and R. salebrosus. Furthermore, ITS sequences of 40 Pterospora root samples from five populations in the province of Quebec provided the first record of the distribution of R. kretzerae, a potentially rare to endangered species, in eastern Canada. [ABSTRACT FROM AUTHOR]

The 1983-1984 Caribbean-wide mass mortality of the once ubiquitous long-spined sea urchin Diadema antillarum Philippi, 1845, is one of several factors considered responsible for coral reef change throughout the region. Unfortunately, there is a paucity of pre-mortality event density data for D. antillarum in the Florida Keys, making it difficult to determine pre-1983 population density levels. Results from surveys conducted during 1970-1973 in the lower Florida Keys, in shallow (<12 m) fore reef habitats, yielded relatively abundant and widespread D. antillarum densities in qualitative transects at five reefs prior to the 1983-1984 die-off. In quantitative surveys at one reef, Middle Sambo Reef in 1972, up to 7.9 individuals m-2 were recorded using quadrats in high-relief spur and groove habitat. A second mortality event in the Florida Keys, beginning in April 1991, again depressed urchin densities that had begun to recover from the 1983-1984 mass mortality. By 1992, D. antillarum densities (<0.01 nr2) were two orders of magnitude lower than pre-die-off estimates (range of 0.07-0.57 m-2 from several spur and groove reefs in the lower Florida Keys) and remained so through 2009. The pre-mortality echinoid density estimates detailed in the Florida Keys provide a baseline to compare with their current population status and should help inform managers about realistic recovery or restoration targets for D. antillarum. [ABSTRACT FROM AUTHOR]

This study was a preliminary analysis of the genetic structure of the ectomycorrhizal species Russula discopus, tL pseudocarmecina and R. ochraceorivulosa with disjunct distributions in continental Africa and Madagascar. Phylogenetic analyses of the nuclear ITS1/5.8S/ITS2 region and the mitochondrial atp6 gene were performed with specimens from both locations for each species along with a suitable outgroup for each of the three taxa. Additional analyses of the ITS1/5.8S/ITS2 region using the African and Malagasy specimens and additional taxa in the genus Russula also were performed. R. pseudocarmecina and R. discopus both exhibited genetic structure as shown by a relatively high percentage difference in ITS and atp6 sequences, high bootstrap support for African or Malagasy groups and the presence of indels in the ITS sequence that are unique to either Africa or Madagascar. African and Malagasy groups of each species were more closely related to each other than to other taxa in Russula. Genetic structure also existed in populations of R. ochraceorivulosa, but bootstrap support was weaker than in the other two species. In addition, there was less sequence divergence in R. ochraceorivulosa and this species was the only one for which the same atp6 haplotype was found in both Africa and Madagascar. Reciprocal monophyly for all three species was consistent with the hypothesis that the same vicariance event may be responsible for the genetic structure observed here, although shorter branch lengths, lower bootstrap support and the presence of the same atp6 haplotype in Africa and Madagascar for R. ochraceorivulosa suggested slower evolutionary rates or geographical isolation after the other two taxa. In addition to the geological events that separated Africa and Madagascar, environmental changes during the Miocene or later might have had an effect on the distribution of these species. [ABSTRACT FROM AUTHOR]

Elaphomyces compleximurus sp. nov. and E. digitatus sp. nov. are described from the Pakaraima Mountains of Guyana. Macromorphological, micromorphological, habitat and DNA sequence data are provided for each new species. This is the first report of Elaphomyces ascomata associated with ectomycorrhizal members of the Fabaceae and also for the genus from the lowland South American tropics. [ABSTRACT FROM AUTHOR]

A phylogenetic analysis of Lactarius sect. Deliciosi was performed based on collections of all known species. Several samples of each species were included, originating from a wide geographic range. The two DNA regions we used (ITS and a part of the gene encoding glyceraldehyde-3-phosphate dehydrogenase) showed an incongruent phylogenetic signal. Much attention was paid to carefully observed macro-and micromorphological characters to draw taxonomic conclusions. We currently accept 38 taxa (31 species and seven varieties) in Lactarius sect. Deliciosi worldwide; four species are new to science. More sampling is needed to resolve the status of the North American varieties. Our knowledge of the Asian species in this section remains fragmentary. The monophyly of the section and its position within Lactarius subgenus Piperites, as proposed in recent morphology-based classification schemes, is confirmed. The intrasectional relationships however do not coincide with the color of the latex (as previously supposed). Intercontinental conspecificity is low in general. The name L. deliciosus is wrongfully applied in North and Central America and only two species seem to occur in both Asia and Europe. [ABSTRACT FROM AUTHOR]

This article discusses various issues related to the folly of Coral Restoration Programs following natural disturbances in the Florida Keys National Marine Sanctuary (FKNMS). Coral reefs around the world have changed dramatically over the past few decades. At the present rate of destruction, reef ecosystems will likely suffer continued significant degradation, possibly to the point of irreversible decline. In FKNMS, one possible course of action is to attempt to restore all damaged and disturbed reefs to fully functional ecosystems at a rate resulting in no net loss of ecosystem value. To date, most coral reef restoration programs within the FKNMS have focused on the physical damage caused by humans, although there has also been a call for intervening and restoring reefs affected by natural disturbances.

Presents a study which documented the changes in nutrient fluxes associated with internal tidal bores arriving on Florida Keys coral reefs. Background of studies on the anthropogenic factors associated with reductions in herbivore populations and the input of dissolved nutrients to reef environments; Methods used; Characteristics of temperature variability across reef sites; Analysis of hydrography and nutrients; Estimates of nitrogen and phosphorus input.

Significant population declines in Acropora cervicornis and A. palmata began in the 1970s and now exceed over 90%. The losses were caused by a combination of coral disease and bleaching, with possible contributions from other stressors, including pollution and predation. Reproduction in the wild by fragment regeneration and sexual recruitment is inadequate to offset population declines. Starting in 2007, the Coral Restoration Foundation™ evaluated the feasibility of outplanting A. cervicornis colonies to reefs in the Florida Keys to restore populations at sites where the species was previously abundant. Reported here are the results of 20 coral outplanting projects with each project defined as a cohort of colonies outplanted at the same time and location. Photogrammetric analysis and in situ monitoring (2007 to 2015) measured survivorship, growth, and condition of 2419 colonies. Survivorship was initially high but generally decreased after two years. Survivorship among projects based on colony counts ranged from 4% to 89% for seven cohorts monitored at least five years. Weibull survival models were used to estimate survivorship beyond the duration of the projects and ranged from approximately 0% to over 35% after five years and 0% to 10% after seven years. Growth rate averaged 10 cm/year during the first two years then plateaued in subsequent years. After four years, approximately one-third of surviving colonies were ≥ 50 cm in maximum diameter. Projects used three to sixteen different genotypes and significant differences did not occur in survivorship, condition, or growth. Restoration times for three reefs were calculated based on NOAA Recovery Plan (NRP) metrics (colony abundance and size) and the findings from projects reported here. Results support NRP conclusions that reducing stressors is required before significant population growth and recovery will occur. Until then, outplanting protects against local extinction and helps to maintain genetic diversity in the wild. [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]

Octocorals, also known as gorgonians and soft corals, were previously managed by the U.S. South Atlantic (SAFMC) and Gulf of Mexico (GMFMC) Fishery Management Councils through a joint Coral Fishery Management Plan (FMP). Because octocorals are mostly collected from Florida waters, the Florida Fish and Wildlife Conservation Commission (FWC) is currently tasked with managing octocoral collection, including the monitoring of colony landings, in the Economic Exclusive Zone (EEZ) adjacent to Florida. Collection of 70,000 colonies per year total, which applies to both state and EEZ waters off Florida, is permitted under Rule 68B- 42.006 of the Florida Administrative Code, but has never been exceeded according to available landings data. Before octocoral management responsibility was transferred to the State of Florida, the SAFMC was concerned that octocoral landings data, as opposed to population data, were being used to set Acceptable Biological Catch limits and Overfishing limits under the new Federal fishery management standards. An additional concern with the octocoral fishery and other organisms captured for the marine aquarium and ornamental fisheries is that large taxonomic groups are lumped together, including species with potentially different life histories and ecological functions. This study assessed some of the characteristics of the octocoral fishery by evaluating FWC Trip Ticket data, conducting interviews with octocoral collectors, and analyzing octocoral life history information and available fishery-independent data on population densities and sizes. Based on interviews with collectors, a synthesis of trip ticket results, and population abundance estimates, the long-term stability of the octocoral fishery is not likely to change significantly. The social dynamics of the aquarium industry to seek colorful, rare, and exotic marine species for home aquaria places octocorals at the lower end of the list of desired species. Octocoral distribution and abundance information obtained from an extensive search of the literature, along with available age, growth, and habitat data, suggests that current information is comprehensive and definitive, such that stock assessment or population dynamic modeling could be considered but are probably not required to assess the status of collected octocoral species. For multiple sampling periods, over a decadal period (1999-09) in the Florida Keys, where most octocoral collection occurs, abundance estimates presented for 15 species illustrate that population sizes are large (tens of millions to hundreds of millions of colonies, per species) and abundance is stable or increasing. For example, the numbers of colonies collected in the Florida Keys in two of the collector categories represented < 0.004% of the estimated population sizes. The collectors and aquarium hobbyists interviewed stated that they would welcome and use a field guide to help with octocoral identification, which would ultimately provide better fishery-dependent taxonomic resolution for collected species. The collection of octocorals below the State of Florida quota of 70,000 colonies per year threshold, which has yet to be reached according to landings data, likely does not adversely affect the octocoral populations targeted. This conclusion is based upon the large population estimates determined for octocorals relative to the small number of colonies collected. This conclusion assumes that the distribution and population sizes of targeted species will continue to be relatively stable or increase. Information collected by the State of Florida through trip tickets is probably adequate to understand and manage the octocoral fishery. Minor reporting clarifications and better taxonomic resolution in reporting would help improve the accuracy of collecting data, but improved accuracy is not required to assess the current state of the fishery-the octocoral fishery is sustainable and would likely remain sustainable at colony collection levels orders of magnitude larger. [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]

Rhizopogonspecies are ecologically significant ectomycorrhizal fungi in conifer ecosystems. The importance of this system merits the development and utilization of a more robust set of molecular markers specifically designed to evaluate their evolutionary ecology. Anonymous nuclear loci (ANL) were developed forR. subgenusAmylopogon. Members of this subgenus occur throughout the United States and are exclusive fungal symbionts associated withPterospora andromedea, a threatened mycoheterotrophic plant endemic to disjunct eastern and western regions of North America. Candidate ANL were developed from 454 shotgun pyrosequencing and assessed for positive amplification across targeted species, sequencing success, and recovery of phylogenetically informative sites. Ten ANL were successfully developed and were subsequently used to sequence representative taxa, herbaria holotype and paratype specimens inR. subgenusAmylopogon. Phylogenetic reconstructions were performed on individual and concatenated data sets by Bayesian inference and maximum likelihood methods. Phylogenetic analyses of these 10 ANL were compared with a phylogeny traditionally constructed using the universal fungal barcode nuc rDNA ITS1-5.8S-ITS2 region (ITS). The resulting ANL phylogeny was consistent with most of the species designations delineated by ITS. However, the ANL phylogeny provided much greater phylogenetic resolution, yielding new evidence for cryptic species within previously defined species ofR. subgenusAmylopogon. Additionally, the rooted ANL phylogeny provided an alternate topology to the ITS phylogeny, which inferred a novel set of evolutionary relationships not identified in prior phylogenetic studies. [ABSTRACT FROM PUBLISHER]

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]

One of the deleterious effects of acute nerve agent exposure is the induction of status epilepticus (SE). If SE is not controlled effectively, it causes extensive brain damage. Here, we review the neuropathology observed after nerve agent-induced SE, as well as the ensuing pathophysiological, neurological, and behavioral alterations, with an emphasis on their time course and longevity. Limbic structures are particularly vulnerable to damage by nerve agent exposure. The basolateral amygdala (BLA), which appears to be a key site for seizure initiation upon exposure, suffers severe neuronal loss; however, GABAergic BLA interneurons display a delayed death, perhaps providing a window of opportunity for rescuing intervention. The end result is a long-term reduction of GABAergic activity in the BLA, with a concomitant increase in spontaneous excitatory activity; such pathophysiological alterations are not observed in the CA1 hippocampal area, despite the extensive neuronal loss. Hyperexcitability in the BLA may be at least in part responsible for the development of recurrent seizures and increased anxiety, while hippocampal damage may underlie the long-term memory impairments. Effective control of SE after nerve agent exposure, such that brain damage is also minimized, is paramount for preventing lasting neurological and behavioral deficits. [ABSTRACT FROM AUTHOR]

Exploitation impacts and management options for 15 coral reef fish species central to the commercial and recreational fisheries of the southern Florida USA coral reef ecosystem were evaluated using a length-based risk analysis (LBRA) framework. Population abundance-at-length composition data were obtained from several regional federal-state sampling programs. These and updated life history demographic data were integrated into a length-based numerical cohort model to generate LBRA fishery sustainability metrics from a probabilistic perspective. Three of five groupers, eight of eight snappers, and two of two grunts were below the 40% spawning potential ratio (SPR) stock sustainability minimum; ten of these stocks are at < 20% of their historical spawning biomass, some as low as 5%. Therefore, to ameliorate overfishing for the 13 stocks with sustainability risks ≥ 98%, fisheries management requires increased minimum sizes of first capture L c and significant reductions in fishing mortality F . To achieve sustainability and reduce sustainability risks area-time protections are also needed. While lack of data often limits the evaluation of management options, this paper establishes benchmarks from which data-limited approaches can move forward. In addition, the approach can be used to cross-check other data-rich analyses. A goal of this work is to effectively balance sustainability risks with fishery production to mitigate overfishing likelihoods and to increase the probability of sustainable fisheries. [ABSTRACT FROM AUTHOR]

The discovery that even small changes in extracellular acidity can alter the excitability of neuronal networks via activation of acid-sensing ion channels (ASICs) could have therapeutic application in a host of neurological and psychiatric illnesses. Recent evidence suggests that activation of ASIC1a, a subtype of ASICs that is widely distributed in the brain, is necessary for the expression of fear and anxiety. Antagonists of ASIC1a, therefore, have been proposed as a potential treatment for anxiety. The basolateral amygdala (BLA) is central to fear generation, and anxiety disorders are characterized by BLA hyperexcitability. To better understand the role of ASIC1a in anxiety, we attempted to provide a direct assessment of whether ASIC1a activation increases BLA excitability. In rat BLA slices, activation of ASIC1a by low pH or ammonium elicited inward currents in both interneurons and principal neurons, and increased spontaneous IPSCs recorded from principal cells significantly more than spontaneous EPSCs. Epileptiform activity induced by high potassium and low magnesium was suppressed by ammonium. Antagonism of ASIC1a decreased spontaneous IPSCs more than EPSCs, and increased the excitability of the BLA network, as reflected by the pronounced increase of evoked field potentials, suggesting that ASIC1a channels are active in the basal state. In vivo activation or blockade of ASIC1a in the BLA suppressed or increased, respectively, anxiety-like behavior. Thus, in the rat BLA, ASIC1a has an inhibitory and anxiolytic function. The discovery of positive ASIC1a modulators may hold promise for the treatment of anxiety disorders. [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]

• Russula brevipes is common ectomycorrhizal (EM) fungus that is associated with several hosts across temperate forest ecosystems. A previous study has demonstrated that substructuring across large geographic distances (1500 km) occurs in the western USA. • To examine genetic structure over a more localized scale, basidiocarps of Russula brevipes from three subpopulations, separated by distances of 230–1090 m, were collected over two consecutive years in an oak/pine woodland. Microsatellite loci were used to test for population differentiation both among subpopulations and by year. • No significant population differentiation was detected between subpopulations (θST = 0.01) or between years (θST = 0.01). Most loci were consistent with a Hardy–Weinburg equilibrium and 82% of the genets between seasons from similar sampling localities constituted new genotypes. • These results indicate that R. brevipes constitutes a randomly mating population with no genetic differentiation between locations or across successive fruiting seasons. [ABSTRACT FROM AUTHOR]

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]

Developmental dyslexia, characterized by unexplainecl difficulty in reading, is associated with behavioral deficits in phonological processing. Functional neuroimaging studies have shown a deficit in the neural mechanisms underlying phonological processing in children and adults with dyslexia. The present study examined whether behavioral remediation ameliorates these dysfunctional neural mechanisms in children with dyslexia. Functional MRI was performed on 20 children with dyslexia (8-12 years old) during phonological processing before and after a remediation program focused on auditory processing and oral language training. Behaviorally, training improved oral language and reading performance. Physiologically, children with dyslexia showed increased activity in multiple brain areas. Increases occurred in left temporo-parietal cortex and left inferior frontal gyrus, bringing brain activation in these regions closer to that seen in normal-reading children. Increased activity was observed also in right-hemisphere frontal and temporal regions and in the anterior cingulate gyrus. Children with dyslexia showed a correlation between the magnitude of increased activation in left temporo-parietal cortex and improvement in oral language ability. These results suggest that a partial remediation of language-processing deficits, resulting in improved reading, ameliorates disrupted function in brain regions associated with phonological processing and produces additional compensatory activation in other brain regions. [ABSTRACT FROM AUTHOR]

Concern about declining trends in coral reef habitats and reef fish stocks in the Florida Keys contributed to the implementation of a network of no-take marine protected areas in 1997. In support of the efforts of the Dry Tortugas National Park and Florida Keys National Marine Sanctuary to implement additional no-take areas in the Tortugas region in 2001, we expanded the scale of our fisheries independent monitoring program for coral reef fishes in the region. To provide a foundation for the habitat-based, stratified random sampling design of the program, we created a digital benthic habitat map of coral reef and hard-bottom habitats in a geographic information system by synthesizing data from bathymetric surveys, side-scan sonar imagery, aerial photogrammetry, existing habitat maps, and in situ visual surveys. Existing habitat maps prior to 1999 were limited to shallow-water (< 20 m depth) soft-sediment, coral reef, and hard-bottom habitats within Dry Tortugas National Park and did not include deeper areas such as the Tortugas Bank, now partially contained within no-take marine protected area boundaries. From diver observations made during the 1999 survey, we developed a classification scheme based on habitat relief and patchiness to describe nine hard-bottom and coral reef habitats encountered from 1-33 m depth. We provide estimates of area by habitat type for no-take marine protected areas in the Tortugas region. Updated information on the spatial distribution and characteristics of benthic habitats will be used to guide future monitoring, assessment, and management activities in the region. Significant data gaps still exist for the western area of the Florida Keys National Marine Sanctuary and are a priority for future research. [ABSTRACT FROM AUTHOR]

Examines the timing of recruitment and species composition in coral reef fishes. Two types of priority effects among coral reef fish assemblages; Construction of underwater reef habitat called Hydrolab; Importance of timing the recruitment of planktonic larvae; Effect of a residence on recruitment.