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Application Of A Bioenergetics Framework For Assessing Sub-Lethal Effects Of Pollutants In The Freshwater Mussel Elliptio Complanata, Christopher G. Goodchild Aug 2014

Application Of A Bioenergetics Framework For Assessing Sub-Lethal Effects Of Pollutants In The Freshwater Mussel Elliptio Complanata, Christopher G. Goodchild

All Theses And Dissertations

Although biomarkers are frequently used to assess sublethal effects of contaminants, a lack of mechanistic linkages to higher-level effects limits the predictive power of biomarkers. Bioenergetics has been proposed as a framework for linking cellular effects to whole-animal effects. We investigated sublethal effects of exposure to wastewater treatment facility effluent in freshwater mussels in situ, thereby capturing ecologically relevant exposure conditions. Our study focused on the energetic biomarker AMP-activated protein kinase (AMPK), while also considering more traditional biomarkers like heat shock proteins (HSP70), and antioxidant enzymes (i.e., superoxide dismutase (SOD), glutathione-S-transferase (GST)). We examined biomarkers at mRNA and protein levels. …


A Unique Covalent Bond In Basement Membrane Is A Primordial Innovation For Tissue Evolution, Aaron L. Fidler, Roberto M. Vanacore, Sergei V. Chetyrkin, Vadim K. Pedchenko, Gautam Bhave, Viravuth P. Yin, Cody L. Stothers, Kristie Lindsey Rose, W. Hayes Mcdonald, Travis A. Clark, Dorin-Bogdan Borza, Robert E. Steele, Michael T. Ivy, The Aspirnauts, Julie K. Hudson, Billy G. Hudson Jan 2014

A Unique Covalent Bond In Basement Membrane Is A Primordial Innovation For Tissue Evolution, Aaron L. Fidler, Roberto M. Vanacore, Sergei V. Chetyrkin, Vadim K. Pedchenko, Gautam Bhave, Viravuth P. Yin, Cody L. Stothers, Kristie Lindsey Rose, W. Hayes Mcdonald, Travis A. Clark, Dorin-Bogdan Borza, Robert E. Steele, Michael T. Ivy, The Aspirnauts, Julie K. Hudson, Billy G. Hudson

Biology Faculty Research

We recently discovered that the collagen IV scaffolds of bovine, mouse, and Drosophila melanogaster tissues are stabilized by sulfilimine chemical bonds (S = N) (20⇓–22). The bond is a covalent cross-link between methionine-93 (Met93) and lysine-211 or hydroxylysine-211 (Lys211/Hyl211) residues that stabilizes the noncollagenous (NC1) interface of adjoining triple helical protomers (Fig. 1A). Peroxidasin, an animal heme peroxidase embedded in basement membrane, forms these sulfilimine cross-links by producing hypohalous acids as intermediates for Met93 oxidization (21, 22). Here, we explored whether the sulfilimine cross-link of collagen IV is a fundamental requirement in the genesis and evolution of tissues in Eumetazoa. …


Lichens Of Six Vernal Pools In Acadia National Park, Me, Usa, J. Barton, B. Ciccotelli, J. E. Gall, F. C. Olday, B. Connery, T. B. Harris, A. M. Fryday, Nishanta Rajakaruna Jan 2014

Lichens Of Six Vernal Pools In Acadia National Park, Me, Usa, J. Barton, B. Ciccotelli, J. E. Gall, F. C. Olday, B. Connery, T. B. Harris, A. M. Fryday, Nishanta Rajakaruna

Faculty Publications, Biological Sciences

Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This work represents the first survey of lichens from vernal pools in Acadia …


Cellular Coping Mechanisms To Hypoxia In The Longhorn Sculpin (Myoxocephalus Octodecemspinosus) Brain, Kelly Heino Jan 2014

Cellular Coping Mechanisms To Hypoxia In The Longhorn Sculpin (Myoxocephalus Octodecemspinosus) Brain, Kelly Heino

College of Graduate Studies: Theses & Dissertations

The loss of neurological function due to hypoxia remains to be a challenge in many species due to the lack of knowledge and understanding of cellular responses. To investigate cellular responses and survival strategies of the brain during hypoxia and post-hypoxia recovery in a moderate hypoxia-tolerant species, with the hopes of identifying possible therapeutic remedies, thirty Longhorn sculpin, Myoxocephalus octodecimspinosus, were challenged with acute hypoxia (40% O2 saturation for 1 h) and twelve additional sculpin were used as controls (~90% O2 saturation). Fish were sampled at each of the following time points: control/normoxic conditions (T=0 h); hypoxic conditions …


Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, Tanner B. Harris, Nishanta Rajakaruna, Sarah J. Nelson, Peter D. Vaux Jul 2012

Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, Tanner B. Harris, Nishanta Rajakaruna, Sarah J. Nelson, Peter D. Vaux

Biological Sciences

Acadia National Park is a center of plant diversity in northeastern North America. The Park's varied habitats and flora are sensitive to a number of natural and anthropogenic perturbations. Stressors such as invasive plants, pest and pathogens, ozone, acidic fog and sulfur deposition, nitrogen deposition, heavy metals, fire and fire suppression, over-browsing, visitor use, hurricanes, and climate change have all had effects on the Park's habitats and plant species at some point and it is unclear how many of these stressors are currently affecting the flora of Acadia National Park. We discuss the botanical diversity of Acadia, assess the natural …


Characterization Of Aquaporin 4 Protein Expression And Localization In Tissues Of The Dogfish (Squalus Acanthias), Christopher P. Cutler, Sheena Harmon, Jonathan Walsh, Kia Burch Feb 2012

Characterization Of Aquaporin 4 Protein Expression And Localization In Tissues Of The Dogfish (Squalus Acanthias), Christopher P. Cutler, Sheena Harmon, Jonathan Walsh, Kia Burch

Biology: Faculty Publications

The role of aquaporin water channels such as aquaporin 4 (Aqp4) in elasmobranchs such as the dogfish Squalus acanthias is completely unknown. This investigation set out to determine the expression and cellular and sub-cellular localization of Aqp4 protein in dogfish tissues. Two polyclonal antibodies were generated (AQP4/1 and AQP4/2) and these showed somewhat different characteristics in Western blotting and immunohistochemistry. Western blots using the AQP4/1 antibody showed two bands (35.5 and 49.5 kDa) in most tissues in a similar fashion to mammals. Liver had an additional band of 57 kDa and rectal gland two further faint bands of 37.5 and …


Enhancing Thermal Tolerance By Eliminating The Pejus Range: A Comparative Study With Three Decapod Crustaceans, Jennifer A. Jost, Stephanie M. Podolski, Markus Frederich Jan 2012

Enhancing Thermal Tolerance By Eliminating The Pejus Range: A Comparative Study With Three Decapod Crustaceans, Jennifer A. Jost, Stephanie M. Podolski, Markus Frederich

Marine Sciences Faculty Publications

Marine invertebrates in the intertidal and subtidal zones are often exposed to highly variable environmental conditions, especially rapid changes in temperature. The ability to survive at different temperatures has previously been described using an extended version of Shelford’s law of tolerance, with optimum, pejus (Latin: ‘turning worse’), and pessimum ranges, and the respective thresholds, critical (Tc) and pejus (Tp) temperatures, that mark the transition from one range into the next. The width of the pejus range, in which the scope for activity gradually declines, varies among species. We tested the hypothesis that the width of the …


Aquaporin 4 Is A Ubiquitously Expressed Isoform In The Dogfish (Squalus Acanthias) Shark, Christopher P. Cutler, Bryce Maciver, Gordon Cramb, Mark L. Zeidel Jan 2012

Aquaporin 4 Is A Ubiquitously Expressed Isoform In The Dogfish (Squalus Acanthias) Shark, Christopher P. Cutler, Bryce Maciver, Gordon Cramb, Mark L. Zeidel

Biology: Faculty Publications

The dogfish ortholog of aquaporin 4 (AQP4) was amplified from cDNA using degenerate PCR followed by cloning and sequencing. The complete coding region was then obtained using 5′ and 3′ RACE techniques. Alignment of the sequence with AQP4 amino acid sequences from other species showed that dogfish AQP4 has high levels (up to 65.3%) of homology with higher vertebrate sequences but lower levels of homology to Agnathan (38.2%) or teleost (57.5%) fish sequences. Northern blotting indicated that the dogfish mRNA was approximately 3.2 kb and was highly expressed in the rectal gland (a shark fluid secretory organ). Semi-quantitative PCR further …


Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, T B. Harris, N Rajakaruna, S J. Nelson, P D. Vaux Jan 2012

Stressors And Threats To The Flora Of Acadia National Park, Maine: Current Knowledge, Information Gaps, And Future Directions, T B. Harris, N Rajakaruna, S J. Nelson, P D. Vaux

Faculty Publications, Biological Sciences

Stressors and threats to the flora of Acadia National Park, Maine: Current knowledge, information gaps, and future directions. J. Torrey Bot. Soc. 139: 323–344. 2012.— Acadia National Park is a center of plant diversity in northeastern North America. The Park's varied habitats and flora are sensitive to a number of natural and anthropogenic perturbations. Stressors such as invasive plants, pest and pathogens, ozone, acidic fog and sulfur deposition, nitrogen deposition, heavy metals, fire and fire suppression, over-browsing, visitor use, hurricanes, and climate change have all had effects on the Park's habitats and plant species at some point and it is …


In Vitro Study Of The Microsporidian Parasite Loma Morhua, Using Cod-Derived Cells And Novel Culture Techniques, Michael J. Macleod Jan 2012

In Vitro Study Of The Microsporidian Parasite Loma Morhua, Using Cod-Derived Cells And Novel Culture Techniques, Michael J. Macleod

Theses and Dissertations (Comprehensive)

The cod populations of the Canadian Atlantic were once highly productive, generating enormous annual harvests and attracting fishing fleets from many nations. However, through the late 1980s improved fishing technology, unprecedented capture rates, and poor fishery management brought wild stocks beyond the point of collapse. Dwindling harvests in the early 1990s resulted in cod fishing moratoriums, and an end to the productivity for which the fishery was once renowned. Atlantic cod remains a popular food worldwide and the collapse of cod fisheries has done little to abate market demands. Consequently, the cod is considered a prime candidate for aquaculture production, …


Morpholino Gene Knockdown In Adult Fundulus Heteroclitus: Role Of Sgk1 In Seawater Acclimation, Emily G. Notch, Joseph R. Shaw, Bonita A. Coutermarsh, Marisa Dzioba, Bruce A. Stanton Dec 2011

Morpholino Gene Knockdown In Adult Fundulus Heteroclitus: Role Of Sgk1 In Seawater Acclimation, Emily G. Notch, Joseph R. Shaw, Bonita A. Coutermarsh, Marisa Dzioba, Bruce A. Stanton

Dartmouth Scholarship

The Atlantic killifish (Fundulus heteroclitus) is an environmental sentinel organism used extensively for studies on environmental toxicants and salt (NaCl) homeostasis. Previous research in our laboratory has shown that rapid acclimation of killifish to seawater is mediated by trafficking of CFTR chloride channels from intracellular vesicles to the plasma membrane in the opercular membrane within the first hour in seawater, which enhances chloride secretion into seawater, thereby contributing to salt homeostasis. Acute transition to seawater is also marked by an increase in both mRNA and protein levels of serum glucocorticoid kinase 1 (SGK1) within 15 minutes of transfer. …


Sam Van Aken: New Edens, Shannon Egan Oct 2011

Sam Van Aken: New Edens, Shannon Egan

Schmucker Art Catalogs

Hybridized fruit trees, grafted orchids on shiny, reflective aluminum pedestals, fluorescent lights placed vertically on stands, and sheets of silver Mylar create a lush and somewhat disorienting space in contemporary artist Sam Van Aken’s most recent body of work New Edens. Van Aken makes Gettysburg College’s Schmucker Art Gallery into a kind of fantastical and futuristic winter garden. Without daylight and despite the cool fall weather of the Northeast, the dozen trees in the gallery are leafy and green, some even bearing fruit. Peach, plum, cherry, nectarine and apricot branches emerge from a single trunk and grow productively alongside their …


A Preliminary Study Of The Vegetation Of Vernal Pools Of Acadia National Park, Maine, U.S.A, Brett Ciccotelli, Tanner B. Harris, Bruce Connery, Nishanta Rajakaruna Jul 2011

A Preliminary Study Of The Vegetation Of Vernal Pools Of Acadia National Park, Maine, U.S.A, Brett Ciccotelli, Tanner B. Harris, Bruce Connery, Nishanta Rajakaruna

Biological Sciences

We conducted a preliminary floristic study of six vernal pools in Acadia National Park on Mount Desert Island, Maine. Plant species were recorded on three sampling dates from April to October, 2008. Sixty-five vascular plant species from 26 families were recorded. Of these, 27 are considered occasional or uncommon in Acadia National Park. Thirteen species are new reports for vernal pools in the northeastern United States. This represents the first published study of the vernal pool flora of Acadia National Park.


A Preliminary Study Of The Vegetation Of Vernal Pools Of Acadia National Park, Mount Desert Island, B Ciccotelli, T B. Harris, B Connery, N Rajakaruna Jan 2011

A Preliminary Study Of The Vegetation Of Vernal Pools Of Acadia National Park, Mount Desert Island, B Ciccotelli, T B. Harris, B Connery, N Rajakaruna

Faculty Publications, Biological Sciences

We conducted a preliminary floristic study of six vernal pools in Acadia National Park on Mount Desert Island, Maine. Plant species were recorded on three sampling dates from April to October, 2008. Sixty-five vascular plant species from 26 families were recorded. Of these, 27 are considered occasional or uncommon in Acadia National Park. Thirteen species are new reports for vernal pools in the northeastern United States. This represents the first published study of the vernal pool flora of Acadia National Park


Reproductive Life History Of Fundulus Jenkensi And Comparative Development Of Five Sympatric Fundulid Species, Eric Thomas Lang Dec 2010

Reproductive Life History Of Fundulus Jenkensi And Comparative Development Of Five Sympatric Fundulid Species, Eric Thomas Lang

Master's Theses

Fundulus jenkinsi is recognized federally and within the state of Mississippi as a Species of Concern. Little is known about the life history of this coastal killifish, but a detailed reproductive histology study of F. jenkinsi and a diagnostic key of the early life stages of select members of Fundulidae can provide the foundation needed to accurately identify it and quantify reproductive parameters in this rare species in need of conservation. Monthly gonadosomatic index (GSI) of male and female F. jenkinsi were documented, and spawning phases and oocyte stages were examined using reproductive histology. In addition, various stages of …


Distribution Of Allatostatin C-Like Immunoreactivity In The Central Nervous System Of The Copepod Crustacean Calanus Finmarchicus, Caroline H. Wilson, Andrew E. Christie Mar 2010

Distribution Of Allatostatin C-Like Immunoreactivity In The Central Nervous System Of The Copepod Crustacean Calanus Finmarchicus, Caroline H. Wilson, Andrew E. Christie

Health Sciences and Kinesiology Faculty Articles

The C-type allatostatins (C-ASTs) are a family of highly pleiotropic arthropod neuropeptides. In crustaceans, transcriptomic/mass spectral studies have identified C-ASTs in the nervous systems of many species; the cellular distributions of these peptides remain unknown. Here, the distribution of C-AST was mapped in the nervous system of the copepod Calanus finmarchicus, the major contributor to the North Atlantic’s zooplanktonic biomass; C-AST-immunopositive neurons were identified in the protocerebrum, in several peripheral ganglia associated with feeding appendages, and in the ganglia controlling the swimming legs, with immunopositive axons present throughout the ventral nerve cord. In addition, axons innervating the dorsal longitudinal …


Ornithocoprophilous Plants Of Mount Desert Rock, A Remote Bird-Nesting Island In The Gulf Of Maine, U.S.A, Nishanta Rajakaruna, Nathaniel S. Pope, Jose Perez-Orozco, Tanner B. Harris Oct 2009

Ornithocoprophilous Plants Of Mount Desert Rock, A Remote Bird-Nesting Island In The Gulf Of Maine, U.S.A, Nishanta Rajakaruna, Nathaniel S. Pope, Jose Perez-Orozco, Tanner B. Harris

Biological Sciences

Plants growing on seabird-nesting islands are uniquely adapted to deal with guano-derived soils high in N and P. Such ornithocoprophilous plants found in isolated, oceanic settings provide useful models for ecological and evolutionary investigations. The current study explored the plants found on Mount Desert Rock (MDR), a small seabird-nesting, oceanic island 44 km south of Mount Desert Island (MDI), Hancock County, Maine, U.S.A. Twenty-seven species of vascular plants from ten families were recorded. Analyses of guano-derived soils from the rhizosphere of the three most abundant species from bird-nesting sites of MDR showed significantly higher (P < 0.05) NO3−, available …


Advances In Serpentine Geoecology: A Retrospective, Nishanta Rajakaruna, Robert S. Boyd Jun 2009

Advances In Serpentine Geoecology: A Retrospective, Nishanta Rajakaruna, Robert S. Boyd

Biological Sciences

(In absence of a text abstract the first paragraph of the paper is provided.)

Serpentine habitats have long provided model settings for geoecological research (reviewed in Alexander et al. 2007, Brady et al. 2005, Brooks 1987, Kazakou et al. 2008, Kruckeberg 1984, Proctor and Woodell 1975, Raja-karuna et al 2009). Serpentine loosely refers to a broad group of minerals associated with the weathering of ultramafi c (high iron and magnesium-rich) rocks found along continental margins and orogenic belts. Soils associated with such rocks often differ from more widespread soils, being less fertile and having high concentrations of some heavy metals. …


Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann Apr 2009

Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann

All Theses And Dissertations

Populations of the gastropod Nucella lapillus are polymorphic for shell color, with light-colored shells predominating on warmer, wave-protected shores and dark-colored shells limited primarily to cooler, wave-exposed shores. During thermal stress, darker shells attain higher body temperatures than lighter shells. These results suggest that heat stress may determine field distribution patterns. However, there is currently little evidence of physiological consequences of thermal stress in these organisms. Following the guiding hypothesis that heat stress leads to cellular energy depletion, we explored whether the central energy regulator AMP-activated Protein Kinase (AMPK) is activated by heat stress. We compared this response in both …


Advances In Serpentine Geoecology: A Retrospective, N Rajakaruna, R S. Boyd Jan 2009

Advances In Serpentine Geoecology: A Retrospective, N Rajakaruna, R S. Boyd

Faculty Publications, Biological Sciences

No abstract provided.


The Effect Of Glutamate On Neurite Outgrowth In Fiddler Crab (Uca Pugilator) X-Organ Cells, Ruth B. Langton Jan 2009

The Effect Of Glutamate On Neurite Outgrowth In Fiddler Crab (Uca Pugilator) X-Organ Cells, Ruth B. Langton

Honors Theses

Glutamate is the primary excitatory neurotransmitter in the mammalian central nervous system. It is of particular interest because of its supposed role in the processes of learning and memory, and also because of its potential toxic effects that have been linked to neurodegenerative diseases, such as Alzheimer’s and Parkinson’s. Although glutamate is necessary for normal cell functioning, high levels of glutamate receptor activation can result in cell death, a phenomenon known as excitotoxicity. It has been suggested that glutamate also plays an important role in the insect and crustacean nervous systems, allowing for the examination of excitotoxicity in these organisms. …


Evaluating Acute Toxicity Of Cadmium To Chironomid Using Hemoglobin As A Molecular Biomarker, Jun Taek Oh Jan 2009

Evaluating Acute Toxicity Of Cadmium To Chironomid Using Hemoglobin As A Molecular Biomarker, Jun Taek Oh

Seton Hall University Dissertations and Theses (ETDs)

Effects of cadmium (Cd), a heavy metal contaminant, on hemoglobin were investigated in aquatic midge fly larvae of the Family, Chironomidae. In this study, chironomid populations from one polluted site, Kearny Marsh, New Jersey, two reference sites, North East Creek, and Bass Harbor, ME, and a laboratory population were taxonomically identified and tested for their sensitivity to Cd. Heavy metals in tissue, water and sediment were analyzed using Atomic Absorption Spectroscopy. Water quality at each site was assessed by measuring pH, dissolved oxygen (DO), oxidation-reduction potential ( eH), salinity and temperature. Hemoglobin proteins in individual larvae were easily detected using …


The Search, The Jackson Laboratory Jan 2008

The Search, The Jackson Laboratory

Search Magazine

No abstract provided.


Lichens Of Pine Hill, A Peridotite Outcrop In Eastern North America, Tanner B. Harris, Fred C. Olday, Nishanta Rajakaruna Dec 2007

Lichens Of Pine Hill, A Peridotite Outcrop In Eastern North America, Tanner B. Harris, Fred C. Olday, Nishanta Rajakaruna

Biological Sciences

Despite a large body of work on the serpentine-substrate effect on vascular plants, little work has been undertaken to describe lichen communities growing on serpentine soils derived from peridotite and other ultramafic rocks. Most such work has been conducted in Europe and western North America. Only one study to date has examined the lichen flora of an ultramafic outcrop in eastern North America. The current paper examines the lichen flora of a peridotite outcrop from Deer Isle, Hancock County, Maine, U.S.A. The lichen flora is presented along with relevant ecological and geochemical data. Sixty-three species were found, comprising 35 genera. …


Fundulus As The Premier Teleost Model In Environmental Biology: Opportunities For New Insights Using Genomics, Bernard Rees Dec 2007

Fundulus As The Premier Teleost Model In Environmental Biology: Opportunities For New Insights Using Genomics, Bernard Rees

Biological Sciences Faculty Publications

A strong foundation of basic and applied research documents that the estuarine fish Fundulus heteroclitus and related species are unique laboratory and field models for understanding how individuals and populations interact with their environment. In this paper we summarize an extensive body of work examining the adaptive responses of Fundulus species to environmental conditions, and describe how this research has contributed importantly to our understanding of physiology, gene regulation, toxicology, and ecological and evolutionary genetics of teleosts and other vertebrates. These explorations have reached a critical juncture at which advancement is hindered by the lack of genomic resources for these …


Genetic Evidence For The Persistence Of The Critically Endangered Sierra Nevada Red Fox In California, John D. Perrine, John P. Pollinger, Benjamin N. Sacks, Reginald H. Barrett, Robert K. Wayne Sep 2007

Genetic Evidence For The Persistence Of The Critically Endangered Sierra Nevada Red Fox In California, John D. Perrine, John P. Pollinger, Benjamin N. Sacks, Reginald H. Barrett, Robert K. Wayne

Biological Sciences

California is home to both the native state-threatened Sierra Nevada red fox (Vulpes vulpes necator), which historically inhabited high elevations of the Sierra Nevada and Cascade mountains, and to multiple low-elevation red fox populations thought to be of exotic origin. During the past few decades the lowland populations have dramatically expanded their distribution, and possibly moved into the historic range of the native high-elevation fox. To determine whether the native red fox persists in its historic range in California, we compared mitochondrial cytochrome-b haplotypes of the only currently-known high-elevation population (n = 9 individuals) to samples …


Temperature Tolerance In Crustaceans: Critical Temperatures And The Heart, Lindsay Haupt (Murray-Miller) Apr 2006

Temperature Tolerance In Crustaceans: Critical Temperatures And The Heart, Lindsay Haupt (Murray-Miller)

All Theses And Dissertations

At certain upper and lower threshold temperatures (critical temperatures (Tc) crustaceans switch to anaerobic metabolism despite sufficient oxygen availability in the environment. I tested the hypothesis that failure of the heart at critical temperatures leads to insufficient oxygen delivery and subsequent anaerobiosis in peripheral tissues.

I exposed rock crabs, Cancer irroratus, as whole animals, and their buffer-perfused semi-isolated hearts to a progressive temperature increase, while monitoring heart rate and lactate accumulation. The whole animals heart rate increased with temperature following a Q10 of 2.8. An abrupt decline in heart rate occurred at 25°C and lactate accumulation occurred between …


Cloning And Sequencing Of Sodium-Hydrogen Exchanger In The Gills Of The Long-Horned Sculpin (Myoxocephalus Octodecimspinosus), Danielle Lee Gunning Jan 2000

Cloning And Sequencing Of Sodium-Hydrogen Exchanger In The Gills Of The Long-Horned Sculpin (Myoxocephalus Octodecimspinosus), Danielle Lee Gunning

College of Graduate Studies: Theses & Dissertations (1964–2006)

No abstract provided.


Trends In Abundance Of The Gulf Of Maine Population Of Harbor Porpoise, Paula Ann Olson Jan 1996

Trends In Abundance Of The Gulf Of Maine Population Of Harbor Porpoise, Paula Ann Olson

Marine Affairs Theses and Major Papers

Hundreds of harbor porpoise die each year as bycatch in the Gulf of Maine's sink gillnet fishery. In recent years, concern has arisen whether the Gulf of Maine population of harbor porpoise can sustain this level of bycatch. It is believed that the population may have declined, or is declining as a result of the incidental moralities. This paper reviews what is known about Gulf of Maine harbor porpoise demographics and how that information is incorporated into the management of the porpoise/fishery interaction. Included in this paper is a new study on the trend of relative abundance of harbor porpoise …


North American Members Of The Hydrellia Crassipes Species Group (Diptera: Ephydridae), D. L. Deonier Mar 1995

North American Members Of The Hydrellia Crassipes Species Group (Diptera: Ephydridae), D. L. Deonier

Insecta Mundi

The known members of the Hydrellia crassipes species group in North America are described or redescribed, including H. crassipes Cresson, H. procteri Cresson, H. saltator Deonier, H. amplecta n.sp., H. bryani n.sp., H. ocalae n.sp., and H. tibiospica n.sp. Adults of these species exhibit the following synapomorphies: dilated male metafemur and expanded (and flange din some) male metatibia and striate (fibrillate) distiphallus. Only a single species (H. tibiospica n.sp.) was reared from its host-plant species, Juncus debilis Gray, but there are associated habitat data to indicate that the entire species group may have sedges andrushes as host plants.