Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Umpolung (2)
- 17β-estradiol (1)
- Acoustic communication (1)
- Alkyne complexes (1)
- Allylation (1)
-
- Ancillary hearing structures (1)
- Arctic passerine (1)
- Auditory evoked potential (1)
- Auditory evoked potentials (1)
- Avian hybrid (1)
- Calcarius lapponicus (1)
- Carbocation (1)
- Crystallin (1)
- Electrophilic aromatic substitution (1)
- Eye (1)
- Fish (1)
- Hair cells (1)
- Iminium (1)
- Indium (1)
- L-proline (1)
- Lapland longspur (1)
- Lens (1)
- Mechanosensory (1)
- Metathesis (1)
- Microarray (1)
- Morpholino (1)
- Multimodal (1)
- Mutant (1)
- OCD (1)
- Oxidative deamination (1)
Articles 1 - 19 of 19
Full-Text Articles in Life Sciences
The Contribution Of The Lateral Line To 'Hearing' In Fish, Dennis M. Higgs, C. A. Radford
The Contribution Of The Lateral Line To 'Hearing' In Fish, Dennis M. Higgs, C. A. Radford
Biological Sciences Publications
In the underwater environment, sound propagates both as a pressure wave and as particle displacement, with particle displacement dominating close to the source (the nearfield). At the receptor level, both the fish ear and the neuromast hair cells act as displacement detectors and both are potentially stimulated by the particle motion component of sound sources, especially in the nearfield. A now common way to test ?hearing' in fish involves auditory evoked potentials (AEPs), with recordings made from electrodes implanted near the auditory brainstem. These AEP recordings are typically conducted in enclosed acoustic environments with the fish well within the nearfield, …
Condition-Dependent Auditory Processing In The Round Goby (Neogobius Melanostomus): Links To Sex, Reproductive Condition And Female Estrogen Levels, Jeffery N. Zeyl, Oliver P. Love, Dennis M. Higgs
Condition-Dependent Auditory Processing In The Round Goby (Neogobius Melanostomus): Links To Sex, Reproductive Condition And Female Estrogen Levels, Jeffery N. Zeyl, Oliver P. Love, Dennis M. Higgs
Biological Sciences Publications
Neural responses to sensory stimuli often differ between sexes, vary seasonally, and can be regulated by endocrine activity, but the ecological and physiological mechanisms driving such patterns are not well understood. The current study examined how auditory function in the round goby (Neogobius melanostomus), a vocal teleost, co-varied with sex, reproductive condition and female plasma 17β-estradiol level. Auditory evoked potentials were collected in response to tone pips (100–600Hz) and a natural round goby pulse vocalization. Additionally, saccule hair cell densities were compared across reproductive groups. Auditory threshold was evaluated in terms of pressure and particle acceleration, and response amplitude and …
Bicatalytic Allylation–Cross-Metathesis Reactions As Γ-Carbonyl Cation Equivalents, Jake R. Henkie, Sugadar Dhaliwal, James R. Green
Bicatalytic Allylation–Cross-Metathesis Reactions As Γ-Carbonyl Cation Equivalents, Jake R. Henkie, Sugadar Dhaliwal, James R. Green
Chemistry and Biochemistry Publications
The products corresponding to the reactions of arenes and γ-carbonyl cations may be obtained by a one-pot, bicatalytic process involving InCl3-catalyzed arene allylation and cross metathesis with electron-deficient alkenes. The process is successful with electronically neutral and electron-rich arenes, and modestly Lewis basic donor groups are tolerated with an increase in InCl3 loading from 10 mol% to 15 mol%, and in one case, 20 mol%.
A Molecular Dynamics (Md) And Quantum Mechanics/Molecular Mechanics (Qm/Mm) Study On Ornithine Cyclodeaminase (Ocd): A Tale Of Two Iminiums, Bogdan F. Ion, Eric Andre Bushnell, Phil De Luna, James Gauld
A Molecular Dynamics (Md) And Quantum Mechanics/Molecular Mechanics (Qm/Mm) Study On Ornithine Cyclodeaminase (Ocd): A Tale Of Two Iminiums, Bogdan F. Ion, Eric Andre Bushnell, Phil De Luna, James Gauld
Chemistry and Biochemistry Publications
Ornithine cyclodeaminase (OCD) is an NAD+-dependent deaminase that is found in bacterial species such as Pseudomonas putida. Importantly, it catalyzes the direct conversion of the amino acid L-ornithine to L-proline. Using molecular dynamics (MD) and a hybrid quantum mechanics/molecular mechanics (QM/MM) method in the ONIOM formalism, the catalytic mechanism of OCD has been examined. The rate limiting step is calculated to be the initial step in the overall mechanism: hydride transfer from the L-ornithine’s Cα–H group to the NAD+cofactor with concomitant formation of a Cα=NH2+ Schiff base with a barrier …
Alkynedicobalt Complexes In Γ-Carbonyl Cations And Cycloheptynedicobalt Complexes, James R. Green
Alkynedicobalt Complexes In Γ-Carbonyl Cations And Cycloheptynedicobalt Complexes, James R. Green
Chemistry and Biochemistry Publications
This Account describes our work on highly electrophilic γ-carbonyl cations featuring propargyldicobalt cations, cycloheptynedicobalt complexes, and the interconnection between the two systems.
1 Introduction
2 γ-Carbonyl Cations via Iron Allyl Cations
3 γ-Carbonyl Cations via Propargyldicobalt Cations
3.1 Synthesis of Velloziolide
3.2 Synthesis of Microstegiol
4 Synthesis of Cycloheptynedicobalt Complexes
4.1 Synthesis via γ-Carbonyl Cations
4.2 Cycloheptynedicobalt Complexes via [4+3] Cycloaddition Reactions
4.3 Cycloheptynedicobalt Complexes via Ring-Closing Metathesis
4.4 Cycloaddition Reactions on Cycloheptynedicobalt Complexes
4.5 Cycloheptynedicobalt Complexes via Intramolecular Nicholas Reactions
5 Dehydrotropylium Ion Co2(CO)6 Complex
6 Final Comments
Pressure And Particle Motion Detection Thresholds In Fish: A Re-Examination Of Salient Auditory Cues In Teleosts, Craig A. Radford, John C. Montgomery, Paul Caiger, Dennis M. Higgs
Pressure And Particle Motion Detection Thresholds In Fish: A Re-Examination Of Salient Auditory Cues In Teleosts, Craig A. Radford, John C. Montgomery, Paul Caiger, Dennis M. Higgs
Biological Sciences Publications
The auditory evoked potential technique has been used for the past 30years to evaluate the hearing ability of fish. The resulting audiograms are typically presented in terms of sound pressure (dB re. 1Pa) with the particle motion (dB re. 1ms–2) component largely ignored until recently. When audiograms have been presented in terms of particle acceleration, one of two approaches has been used for stimulus characterisation: measuring the pressure gradient between two hydrophones or using accelerometers. With rare exceptions these values are presented from experiments using a speaker as the stimulus, thus making it impossible to truly separate the contribution of …
First Report Of A Snow Bunting × Lapland Longspur Hybrid, Christie A. Macdonald, Tracy Martin, Rick Ludkin, David J.T. Hussell, David Lamble, Oliver P. Love
First Report Of A Snow Bunting × Lapland Longspur Hybrid, Christie A. Macdonald, Tracy Martin, Rick Ludkin, David J.T. Hussell, David Lamble, Oliver P. Love
Integrative Biology Publications
In late April 2011, photographs of an apparent male snow bunting (Plectrophenax nivalis) × Lapland longspur (Calcarius lapponicus) hybrid were taken at St. Lewis Inlet, Newfoundland and Labrador, Canada, while the bird was foraging in a mixed flock of both species along a previously documented spring migratory route. As far as we are aware, this is the first hybridization of these species documented anywhere in the world. The bird was identified as a male on the basis of longspur nape coloration, and it appears to have the head, beak, and back coloration and patterning of a Lapland longspur, but the …
Complex Genetic Patterns In Closely Related Colonizing Invasive Species, Aibin Zhan, John A. Darling, Dan G. Bock, Ana‹S Lacoursišre-Roussel, Hugh J. Macisaac, Melania E. Cristescu
Complex Genetic Patterns In Closely Related Colonizing Invasive Species, Aibin Zhan, John A. Darling, Dan G. Bock, Ana‹S Lacoursišre-Roussel, Hugh J. Macisaac, Melania E. Cristescu
Biological Sciences Publications
Anthropogenic activities frequently result in both rapidly changing environments and translocation of species from their native ranges (i.e., biological invasions). Empirical studies suggest that many factors associated with these changes can lead to complex genetic patterns, particularly among invasive populations. However, genetic complexities and factors responsible for them remain uncharacterized in many cases. Here, we explore these issues in the vase tunicate Ciona intestinalis (Ascidiacea: Enterogona: Cionidae), a model species complex, of which spA and spB are rapidly spreading worldwide. We intensively sampled 26 sites (N= 873) from both coasts of North America, and performed phylogenetic and population genetics analyses …
Depth And Temperature Preferences Of The Deepwater Flatfish Greenland Halibut Reinhardtius Hippoglossoides In An Arctic Marine Ecosystem, I. Peklova, N. E. Hussey, K. J. Hedges, M. A. Treble, A. T. Fisk
Depth And Temperature Preferences Of The Deepwater Flatfish Greenland Halibut Reinhardtius Hippoglossoides In An Arctic Marine Ecosystem, I. Peklova, N. E. Hussey, K. J. Hedges, M. A. Treble, A. T. Fisk
Biological Sciences Publications
No abstract provided.
Evaluating Risk Effects Of Industrial Features On Woodland Caribou Habitat Selection In West Central Alberta Using Agent-Based Modelling, Christina A. D. Semeniuk, M. Musiani, M. Hebblewhite, S. Grindal, D. J. Marceau
Evaluating Risk Effects Of Industrial Features On Woodland Caribou Habitat Selection In West Central Alberta Using Agent-Based Modelling, Christina A. D. Semeniuk, M. Musiani, M. Hebblewhite, S. Grindal, D. J. Marceau
Biological Sciences Publications
No abstract provided.
First Report Of A Snow Bunting × Lapland Longspur Hybrid, Christie A. Macdonald, Tracy Martin, Rick Ludkin, David J.T. Hussell, David Lamble, Oliver Love
First Report Of A Snow Bunting × Lapland Longspur Hybrid, Christie A. Macdonald, Tracy Martin, Rick Ludkin, David J.T. Hussell, David Lamble, Oliver Love
Biological Sciences Publications
In late April 2011, photographs of an apparent male snow bunting (Plectrophenax nivalis) × Lapland longspur (Calcarius lapponicus) hybrid were taken at St. Lewis Inlet, Newfoundland and Labrador, Canada, while the bird was foraging in a mixed flock of both species along a previously documented spring migratory route. As far as we are aware, this is the first hybridization of these species documented anywhere in the world. The bird was identified as a male on the basis of longspur nape coloration, and it appears to have the head, beak, and back coloration and patterning of a Lapland longspur, but the …
Inconsistent Geographic Variation In The Calls And Duets Of Barred Owls (Strix Varia) Across An Area Of Genetic Introgression, Karan J. Odom, Daniel J. Mennill
Inconsistent Geographic Variation In The Calls And Duets Of Barred Owls (Strix Varia) Across An Area Of Genetic Introgression, Karan J. Odom, Daniel J. Mennill
Biological Sciences Publications
Much of our understanding of vocal geographic variation in birds is based on the dialects of oscine songbirds that learn their songs. Recent studies have revealed that nonoscine vocal behavior is more complex than previously thought, yet we still have a rudimentary understanding of how vocalizations of suboscine and nonpasserine birds are infuenced by genetic and geographic variation. We examined geographic variation in male calls, female calls, and duets of Barred Owls (Strix varia) among 10 locations across the southeastern United States. Recent molecular work revealed two genetically distinct clades of Barred Owl at either end of our transect, with …
Low Levels Of Extra-Pair Paternity In A Neotropical Duetting Songbird, The Rufous-And-White Wren (Thryothorus Rufalbus), Sarah B. Douglas, Daniel D. Heath, Daniel J. Mennill
Low Levels Of Extra-Pair Paternity In A Neotropical Duetting Songbird, The Rufous-And-White Wren (Thryothorus Rufalbus), Sarah B. Douglas, Daniel D. Heath, Daniel J. Mennill
Biological Sciences Publications
Molecular analyses have confirmed that the majority of socially monogamous birds follow a genetically promiscuous reproductive strategy. Most such studies, however, have addressed species of the North Temperate Zone; tropical species are grossly underrepresented, although most of Earth's biodiversity is concentrated in the tropics. In this study, we describe the genetic mating strategy of the Rufous-and-white Wren (Thryothorus rufalbus), a socially monogamous duetting neotropical songbird. Over 8 years of studying a marked population in Costa Rica, we recorded genetic data from 51 broods. Microsatellite analysis of four variable loci revealed that the Rufous-and-white Wren follows a mixed reproductive strategy, where …
Plant Feeding In An Omnivorous Mirid, Dicyphus Hesperus: Why Plant Context Matters, David R. Gillespie, Sherah L. Vanlaerhoven, Robert R. Mcgregor, Shannon Chan, Bernard Roitberg
Plant Feeding In An Omnivorous Mirid, Dicyphus Hesperus: Why Plant Context Matters, David R. Gillespie, Sherah L. Vanlaerhoven, Robert R. Mcgregor, Shannon Chan, Bernard Roitberg
Biological Sciences Publications
True omnivores that feed on both plant and animal tissues are not additive combinations of herbivore and predator (carnivore). Because true omnivores must distribute adaptive feeding decisions among two disparate tissue types, understanding the context that plants provide for foraging is important to understand their role in food webs. We varied prey and plant resources to investigate the plant context in an omnivorous true bug, Dicyphus hesperus. The contribution of plant species to fitness was unimportant in water acquisition decisions, but affected numbers of prey consumed over longer periods. In plant communities, in the absence of prey, D. hesperus moved …
The Level And Distribution Of The Gababr1 And Gababr2 Receptor Subunits In The Rat's Inferior Colliculus, Lena Jamal, Aziz N. Khan, Sehrish Butt, Chirag R. Patel, Huiming Zhang
The Level And Distribution Of The Gababr1 And Gababr2 Receptor Subunits In The Rat's Inferior Colliculus, Lena Jamal, Aziz N. Khan, Sehrish Butt, Chirag R. Patel, Huiming Zhang
Biological Sciences Publications
The type B γ-aminobutyric acid receptor (GABAB receptor) is an important neurotransmitter receptor in the midbrain auditory structure, the inferior colliculus (IC). A functional GABAB receptor is a heterodimer consisting of two subunits, GABABR1 and GABABR2. Western blotting and immunohistochemical experiments were conducted to examine the expression of the two subunits over the IC including its central nucleus, dorsal cortex, and external cortex (ICc, ICd, and ICx). Results revealed that the two subunits existed in both cell bodies and the neuropil throughout the IC. The two subunits had similar regional distributions over the IC. The combined level of cell body …
Evolution And Emergence: A Re-Evaluation Of The New Synthesis, Michael J. Crawford
Evolution And Emergence: A Re-Evaluation Of The New Synthesis, Michael J. Crawford
Biological Sciences Publications
The modern obsession with methodological reductionism in some areas of biology is arguably a product of the exquisitely precise tools now available to dissect problems. Reductionist approaches assume that an understanding of atomized parts will be sufficient to approximate an understanding of the whole. Ironically, the sheer success of this approach and the consequent volume of data generated, particularly as a result of the genome projects, has made comprehension of the larger picture problematic. Consequently, historical patterns of more phenomenologically oriented analyses are re-emerging. This impulse is not new: Gould and Lewontin (1979) argued for a less reductionist view of …
Microarray-Based Identification Of Pitx3 Targets During Xenopus Embryogenesis, L Hooker, C Smoczer, Farhad Khosrowshahian, Michael J. Crawford
Microarray-Based Identification Of Pitx3 Targets During Xenopus Embryogenesis, L Hooker, C Smoczer, Farhad Khosrowshahian, Michael J. Crawford
Biological Sciences Publications
Background: Unexpected phenotypes resulting from morpholino-mediated translational knockdown of Pitx3 in Xenopus laevis required further investigation regarding the genetic networks in which the gene might play a role. Microarray analysis was, therefore, used to assess global transcriptional changes downstream of Pitx3. Results: From the large data set generated, selected candidate genes were confirmed by reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization. Conclusions: We have identified four genes as likely direct targets of Pitx3 action: Pax6, beta Crystallin-b1 (Crybb1), Hes7.1, and Hes4. Four others show equivocal promise worthy of consideration: Vent2, and Ripply2 (aka Ledgerline or Stripy), eFGF and …
The Cyclin-Like Protein Spy1/Ringo Promotes Mammary Transformation And Is Elevated In Human Breast Cancer, Mohammad Al Sorkhy, Rosa-Maria Ferraiuolo, Espanta Jalili, Agnes Malysa, Andreea R. Fratiloiu, Bonnie F. Sloane, Lisa A. Porter
The Cyclin-Like Protein Spy1/Ringo Promotes Mammary Transformation And Is Elevated In Human Breast Cancer, Mohammad Al Sorkhy, Rosa-Maria Ferraiuolo, Espanta Jalili, Agnes Malysa, Andreea R. Fratiloiu, Bonnie F. Sloane, Lisa A. Porter
Biological Sciences Publications
Background: Spy1 is a novel 'cyclin-like' activator of the G1/S transition capable of enhancing cell proliferation as well as inhibiting apoptosis. Spy1 protein levels are tightly regulated during normal mammary development and forced overexpression in mammary mouse models accelerates mammary tumorigenesis. Methods: Using human tissue samples, cell culture models and in vivo analysis we study the implications of Spy1 as a mediator of mammary transformation and breast cancer proliferation. Results: We demonstrate that this protein can facilitate transformation in a manner dependent upon the activation of the G2/M Cdk, Cdk1, and the subsequent inhibition of the anti-apoptotic regulator FOXO1. Importantly, …
Low Levels Of Extra-Pair Paternity In A Neotropical Duetting Songbird, The Rufous-And-White Wren (Thryothorus Rufalbus), Sarah B. Douglas, Daniel D. Heath, Daniel J. Mennill
Low Levels Of Extra-Pair Paternity In A Neotropical Duetting Songbird, The Rufous-And-White Wren (Thryothorus Rufalbus), Sarah B. Douglas, Daniel D. Heath, Daniel J. Mennill
Great Lakes Institute for Environmental Research Publications
Molecular analyses have confirmed that the majority of socially monogamous birds follow a genetically promiscuous reproductive strategy. Most such studies, however, have addressed species of the North Temperate Zone; tropical species are grossly underrepresented, although most of Earth's biodiversity is concentrated in the tropics. In this study, we describe the genetic mating strategy of the Rufous-and-white Wren (Thryothorus rufalbus), a socially monogamous duetting neotropical songbird. Over 8 years of studying a marked population in Costa Rica, we recorded genetic data from 51 broods. Microsatellite analysis of four variable loci revealed that the Rufous-and-white Wren follows a mixed reproductive strategy, where …