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Populations of aspen (Populus tremuloides Michx.) with different evolutionary histories differ in their climate occupancy
Get PDFQuaking aspens (Populus tremuloides Michx.) are found in diverse habitats throughout North America. While the biogeography of aspens' distribution has been documented, the drivers of the phenotypic diversity of aspen are still being explored. In our study, we examined differences in climate between northern and southwestern populations of aspen, finding large-scale differences between the populations. Our results suggest that northern and southwestern populations live in distinct climates and support the inclusion of genetic and phenotypic data with species distribution modeling for predicting aspens' distribution.This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons, Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758Keywords: biogeography, ecological genetics, Biodiversity, phyloclimatic modeling, climate nich
Use of Multidetector Computed Tomography in the Assessment of Dogs with Pericardial Effusion
Get PDFBackground: Contrast-enhanced multidetector computed tomography ( MDCT) allows high spatial and temporal resolution imaging of cardiac, thoracic, and abdominal structures. Accurate determination of the cause of pericardial effusion ( PE) is essential to providing appropriate treatment and prognosis. Echocardiography and pericardial fluid analysis may not differentiate between causes of PE and cannot identify extracardiac metastasis. Hypothesis/ Objectives: Describe the thoracic and abdominal MDCT findings and evaluate the utility of MDCT to differentiate between neoplastic and nonneoplastic causes of PE in dogs. Animals: Eleven client-owned dogs with PE diagnosed by echocardiography. Methods: Prospective observational study. Transthoracic echocardiography ( TTE), 3-view thoracic radiography, and contrast-enhanced thoracic and abdominal MDCT images were evaluated for the presence of cardiac masses, pulmonary metastases, and abdominal masses. Histopathology in 5 dogs and survival analysis in all dogs were evaluated. Results: A neoplastic cause was identified in 6/ 11 dogs and a nonneoplastic cause was identified in 5/ 11. Cardiac MDCT findings were consistent with TTE findings in all dogs with right atrial ( 5/ 5) and heart base masses ( 1/ 1). Pulmonary metastases were identified in 1/ 11 dogs by thoracic radiography and in 2/ 11 dogs by MDCT. MDCT identified splenic or hepatic lesions consistent with neoplasia in 6/ 11 and 5/ 11 dogs, respectively. Focal MDCT pericardial changes at the pericardiocentesis site were noted in 3/ 11 dogs.
Conclusions and Clinical Importance: Multidetector computed tomography did not improve the detection of cardiac masses in dogs with PE over echocardiography. The benefit of MDCT was primarily in the detection of pulmonary metastases and extracardiac lesions using a single imaging modality.Keywords: Cardiac tumors, Echocardiography, Cardiolog
Speedups of ergodic group extensions
Get PDFAbstract: We prove that for all ergodic extensions S-1 of a transformation by a locally compact second countable group G, and for all G-extensions S₂ of an aperiodic transformation, there is a relative speedup of S₁ that is relatively isomorphic to S₂. We apply this result to give necessary and sufficient conditions for two ergodic n-point or countable extensions to be related in this way.Keywords: Classification, Factor orbit equivalence, Compact group extension
A multigene phylogenetic synthesis for the class Lecanoromycetes (Ascomycota): 1307 fungi representing 1139 infrageneric taxa, 317 genera and 66 families
Get PDFThe Lecanoromycetes is the largest class of lichenized Fungi, and one of the most species-rich classes in the
kingdom. Here we provide a multigene phylogenetic synthesis (using three ribosomal RNA-coding and two
protein-coding genes) of the Lecanoromycetes based on 642 newly generated and 3329 publicly available
sequences representing 1139 taxa, 317 genera, 66 families, 17 orders and five subclasses (four currently
recognized: Acarosporomycetidae, Lecanoromycetidae, Ostropomycetidae, Umbilicariomycetidae; and one provisionarily recognized, ‘Candelariomycetidae’). Maximum likelihood phylogenetic analyses on four
multigene datasets assembled using a cumulative supermatrix approach with a progressively higher
number of species and missing data (5-gene, 5 + 4-gene, 5 + 4 + 3-gene and 5 + 4 + 3 + 2-gene datasets)
show that the current classification includes non-monophyletic taxa at various ranks, which need to be
recircumscribed and require revisionary treatments based on denser taxon sampling and more loci. Two
newly circumscribed orders (Arctomiales and Hymeneliales in the Ostropomycetidae) and three families
(Ramboldiaceae and Psilolechiaceae in the Lecanorales, and Strangosporaceae in the Lecanoromycetes
inc. sed.) are introduced. The potential resurrection of the families Eigleraceae and Lopadiaceae is considered
here to alleviate phylogenetic and classification disparities. An overview of the photobionts associated
with the main fungal lineages in the Lecanoromycetes based on available published records is provided. A
revised schematic classification at the family level in the phylogenetic context of widely accepted and
newly revealed relationships across Lecanoromycetes is included. The cumulative addition of taxa with
an increasing amount of missing data (i.e., a cumulative supermatrix approach, starting with taxa for which
sequences were available for all five targeted genes and ending with the addition of taxa for which only two
genes have been sequenced) revealed relatively stable relationships for many families and orders.
However, the increasing number of taxa without the addition of more loci also resulted in an expected substantial
loss of phylogenetic resolving power and support (especially for deep phylogenetic relationships),
potentially including the misplacements of several taxa. Future phylogenetic analyses should include
additional single copy protein-coding markers in order to improve the tree of the Lecanoromycetes. As part
of this study, a new module (‘‘Hypha’’) of the freely available Mesquite software was developed to compare
and display the internodal support values derived from this cumulative supermatrix approach.Keywords: Classification, Multi-gene phylogeny, Lichenized fungi, Systematics, Cumulative supermatrix, Lecanoromycete
Analysis of clock-regulated genes in Neurospora reveals widespread posttranscriptional control of metabolic potential
Get PDFNeurospora crassa has been for decades a principal model for filamentous fungal genetics and physiology as well as for understanding the mechanism of circadian clocks. Eukaryotic fungal and animal clocks comprise transcription-translation-based feedback loops that control rhythmic transcription of a substantial fraction of these transcriptomes, yielding the changes in protein abundance that mediate circadian regulation of physiology and metabolism: Understanding circadian control of gene expression is key to understanding eukaryotic, including fungal, physiology. Indeed, the isolation of clock-controlled genes (ccgs) was pioneered in Neurospora where circadian output begins with binding of the core circadian transcription factor WCC to a subset of ccg promoters, including those of many transcription factors. High temporal resolution (2-h) sampling over 48 h using RNA sequencing (RNA-Seq) identified circadianly expressed genes in Neurospora, revealing that from ∼10% to as much 40% of the transcriptome can be expressed under circadian control. Functional classifications of these genes revealed strong enrichment in pathways involving metabolism, protein synthesis, and stress responses; in broad terms, daytime metabolic potential favors catabolism, energy production, and precursor assembly, whereas night activities favor biosynthesis of cellular components and growth. Discriminative regular expression motif elicitation (DREME) identified key promoter motifs highly correlated with the temporal regulation of ccgs. Correlations between ccg abundance from RNA-Seq, the degree of ccg-promoter activation as reported by ccg-promoter-luciferase fusions, and binding of WCC as measured by ChIP-Seq, are not strong. Therefore, although circadian activation is critical to ccg rhythmicity, posttranscriptional regulation plays a major role in determining rhythmicity at the mRNA level.Keywords: Clock-controlled genes, Circadian, Transcription, Neurospora, RNA-Se
Release of dissolved organic matter by coastal diatoms
Get PDFDissolved organic matter (DOM) production was examined in axenic batch cultures of five coastal diatom species. For Chaetoceros decipiens, dissolved organic carbon (DOC) accumulated beginning in late exponential growth as a result of increased cell density. For Cylindrotheca closterium, DOC actually decreased in late exponential growth and reached zero by the end of the experiment. This coincided with continued particulate organic carbon (POC) production and a threefold increase in the per‐cell concentration of transparent exopolymer particles after nutrients were depleted. DOC release rates varied between species but were significantly higher for all five species in exponential or transition growth than during stationary growth. On average, 5% of the total fixed C was released as DOC for four of the diatoms, whereas C. decipiens released ~21% of its fixed C as DOC. The percentage of fixed C released as DOC varied little with nutrient availability or diatom growth stage. The DOM produced by some diatom species adheres to filters and is measured in the particulate organic matter (POM) fraction when cells are separated from the medium by filtration. This may be an important problem when diatom species with known benthic life histories are prevalent. In contrast, for species like Chaetoceros that have no benthic life history, DOM release rates estimated by bulk measurements or ¹⁴C appear to be accurate. Overall, these results indicate that the species composition of phytoplankton blooms has the potential to influence the relative importance of POM and DOM production and can complicate interpretation of those measurements.Keywords: Coastal diatoms, Dissolved organic matte
Jet stream intraseasonal oscillations drive dominant ecosystem variations in Oregon’s summertime coastal upwelling system
Get PDFSummertime wind stress along the coast of the northwestern United States typically exhibits intraseasonal oscillations (ISOs) with periods from ≈15 to 40 days, as well as fluctuations on the 2- to 6-day “weather-band” and 1-day diurnal time scales. Coastal upwelling of cool, nutrient-rich water is driven by extended periods of equatorward alongshore winds, and we show that the ≈20-day ISOs in alongshore wind stress dominated the upwelling process during summer 2001 off Oregon. These wind stress ISOs resulted from north–south positional ISOs of the atmospheric jet stream (JS). Upper-ocean temperature, phytoplankton, and zooplankton varied principally on the ≈20-day time scale as well, and these correlated with the ISOs in alongshore wind stress and JS position, even though there also were weather-band stress fluctuations of comparable magnitude. Such wind stress ISOs are typical along Oregon in the summer upwelling season, occurring in 10 of 12 years examined, including 2001. We present a previously unreported direct connection from the atmospheric JS to oceanic primary and secondary production on the intraseasonal time scale and show the leading importance of ISOs in driving this coastal upwelling ecosystem during a typical summer.Keywords: coastal variability, coastal marine ecosystems, marine ecology, wind-driven ocean upwellin
Academic standing of undergraduate students, Fall 2002 through Winter 2006
No full textThe summary data reports academic standing of undergraduate students at the end of each term, Fall 2002 (200301) through Winter 2006 (200602) showing academic reinstatements as of the beginning of the term, arranged by college.Keywords: Academic suspension,
Academic probation,
Good standing,
Academic standing,
Academic warning,
Academic reinstatemen
Western Cooperative Spray Project : 1963
No full textThis report includes information concerning experimental use of unregistered pesticides or unregistered uses of pesticides. Experimental results should not be interpreted as recommendations for use. Use of unregistered materials or use of any registered pesticides inconsistent with its label is against both Federal Law and State Law