29 research outputs found
XIII - Literature 1780-1830: The Romantic Period
This chapter has four sections: 1. General and Prose; 2. The Novel; 3. Poetry; 4. Drama. Section 1 is by Maxine Branagh-Miscampbell; section 2 by Barbara Leonardi; section 3 by Matthew Ward and Paul Whickman; section 4 is by Omar F. Mirand
Multiple plant traits shape the genetic basis of herbivore community assembly
1. Community genetics research has posited a genetic basis to the assembly of ecological communities. For arthropod herbivores in particular, there is strong support that genetic variation in host plants is a key factor shaping their diversity and composition. However, the specific plant phenotypes underlying herbivore responses remain poorly explored for most systems.
2. We address this knowledge gap by examining the influence of both genetic and phenotypic variation in a dominant host-plant species, Salix hookeriana, on its associated arthropod herbivore community in a common garden experiment. Specifically, we surveyed herbivore responses among five different arthropod feeding guilds to 26 distinct S. hookeriana genotypes. Moreover, we quantified the heritability of a suite of plant traits that determine leaf quality (e.g. phenolic compounds, trichomes, specific leaf area, C : N) and whole-plant architecture, to identify which traits best accounted for herbivore community responses to S. hookeriana genotype.
3. We found that total herbivore abundance and community composition differed considerably among S. hookeriana genotypes, with strong and independent responses of several species and feeding guilds driving these patterns. We also found that leaf phenolic chemistry displayed extensive heritable variation, whereas leaf physiology and plant architecture tended to be less heritable. Of these traits, herbivore responses were primarily associated with leaf phenolics and plant architecture; however, different herbivore species and feeding guilds were associated with different sets of traits. Despite our thorough trait survey, plant genotype remained a significant predictor of herbivore responses in most trait association analyses, suggesting that unmeasured host-plant characteristics and/or interspecific interactions were also contributing factors.
4. Taken together, our results support that the genetic basis of herbivore community assembly occurs through a suite of plant traits for different herbivore species and feeding guilds. Still, identifying these phenotypic mechanisms requires measuring a broad range of plant traits and likely further consideration of how these traits affect interspecific interactions.Fil: Barbour, Matthew A.. University Of British Columbia; CanadáFil: Rodriguez Cabal, Mariano Alberto. University Of British Columbia; Canadá. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue; ArgentinaFil: Wu, Elizabeth T.. Humboldt State University; Estados UnidosFil: Julkunen Tiitto, Riitta. University of Eastern Finland; FinlandiaFil: Ritland, Carol E.. University Of British Columbia; CanadáFil: Miscampbell, Allyson E.. University Of British Columbia; CanadáFil: Jules, Erik S.. Humboldt State University; Estados UnidosFil: Crutsinger, Gregory M.. University Of British Columbia; Canad
Investigating mechanisms of state localization in highly ionized dense plasmas
Producción CientíficaWe present experimental observations of Kβ emission from highly charged Mg ions at solid density, driven by intense x rays from a free electron laser. The presence of Kβ emission indicates the n=3 atomic shell is relocalized for high charge states, providing an upper constraint on the depression of the ionization potential. We explore the process of state relocalization in dense plasmas from first principles using finite-temperature density functional theory alongside a wave-function localization metric, and find excellent agreement with experimental results.This work has been supported by the Spanish Ministry of Science and Innovation under Research Grant No. PID2019-108764RB-I0
Investigating Mechanisms of State Localization in Highly-Ionized Dense Plasmas
We present the first experimental observation of K emission from
highly charged Mg ions at solid density, driven by intense x-rays from a free
electron laser. The presence of K emission indicates the atomic
shell is relocalized for high charge states, providing an upper constraint on
the depression of the ionization potential. We explore the process of state
relocalization in dense plasmas from first principles using finite-temperature
density functional theory alongside a wavefunction localization metric, and
find excellent agreement with experimental results.Comment: 22 pages, 13 figure
Mapping the Electronic Structure of Warm Dense Nickel via Resonant Inelastic X-ray Scattering
The development of high-brightness free-electron lasers (FEL) has
revolutionised our ability to create and study matter in the
high-energy-density (HED) regime. Current diagnostic techniques have been very
successful in yielding information on fundamental thermodynamic plasma
properties, but provide only limited or indirect information on the detailed
quantum structure of these systems, and on how it is affected by ionization
dynamics. Here we show how the electronic structure of solid-density nickel,
heated to temperatures of 10's of eV on femtosecond timescales, can be studied
by resonant (Raman) inelastic x-ray scattering (RIXS) using the Linac Coherent
Light Source FEL. We present single-shot measurements of the valence density of
states in the x-ray-heated transient system, and extract simultaneously
electron temperatures, ionization, and ionization potential energies. The RIXS
spectrum provides a wealth of information on the valence structure of the HED
system that goes beyond what can be extracted from x-ray absorption or emission
spectroscopy alone
Molecular phylogeny of an ancient rodent family (Aplodontiidae)
The family Aplodontiidae contains a single, monotypic extant genus, Aplodontia (mountain beaver), which was first described by Rafinesque in 1817. Phylogenetic studies have shown that it is the sister lineage to squirrels. Aplodontia rufa is endemic to the Pacific Northwest and ranges from central California to British Columbia, Canada. Currently, 7 described subspecies are recognized based on morphological taxonomic studies. In this study, mitochondrial and nuclear genes were sequenced to infer molecular phylogenies of A. rufa. One of the goals of this study was to use molecular data to test the current taxonomic hypothesis based on morphology. Another goal was to incorporate geographic information to elucidate distributions of major clades. Our results support the previously held subspecies designations based on morphological taxonomy, with 1 main exception: we determined that within A. rufa, the subspecies A. rufa rainieri and A. rufa rufa north of the Columbia River represent a single lineage and should revert to the name A. rufa olympica. Although we revised geographic boundaries for some groups (A. r. rufa, A. r. olympica, and A. r. pacifica), only the conservation status and management of A. r. olympica (previously 2 subspecies) in Canada may be affected. Our findings support the continued conservation efforts for the isolated and endangered lineages present in coastal California
Data from: Molecular phylogeny of an ancient rodent family (Aplodontiidae)
The family Aplodontiidae contains a single, monotypic extant genus, Aplodontia (mountain beaver), which was 1st described by Rafinesque in 1817. Phylogenetic studies have shown that it is the sister lineage to squirrels. Aplodontia rufa is endemic to the Pacific Northwest and ranges from central California to British Columbia. Currently, 7 described subspecies are recognized based on morphological taxonomic studies. In this study, mitochondrial and nuclear genes were sequenced to infer molecular phylogenies of A. rufa. One of the goals of this study was to test the current taxonomic hypothesis based on morphology with molecular data. Another goal was to incorporate geographic information to elucidate distributions of major clades. Our results support the previously held subspecies designations based on morphological taxonomy, with 1 main exception: we determined that within A. rufa, the subspecies A. rufa rainieri and A. rufa rufa north of the Columbia River represent a single lineage and should revert to the name A. rufa olympica. Although we revised geographic boundaries for some groups (A. r. rufa, A. r. olympica, A. r. pacifica), only the conservation status and management of A. r. olympica (previously 2 subspecies) in Canada may be affected. Our findings support the continued conservation efforts for the isolated and endangered lineages present in coastal California
all nuc.TXT
BEAST input file:GHR nuclear DNA sequence