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Full-Text Articles in Biology

Episodic Physical Forcing And The Structure Of Phytoplankton Communities In The Coastal Waters Of New Jersey, Mark A. Moline, Shelley M. Blackwell, Robert Chant, Matthew J. Oliver, Trisha Bergmann, Scott Glenn, Oscar M.E. Schofield Dec 2004

Episodic Physical Forcing And The Structure Of Phytoplankton Communities In The Coastal Waters Of New Jersey, Mark A. Moline, Shelley M. Blackwell, Robert Chant, Matthew J. Oliver, Trisha Bergmann, Scott Glenn, Oscar M.E. Schofield

Biological Sciences

The high variability in physical, biological, and chemical properties in coastal waters have limited our ability to sample the appropriate timescale and space scale to resolve physical forcing of the ecosystem. To improve our understanding, a multiplatform adaptive sampling program at the Long-term Ecosystem Observatory(LEO-15) off the coast of New Jersey examined the relationship between episodic summertime upwelling and downwelling events and the corresponding dynamics in bulk phytoplankton biomass and community structure. Inherent and apparent optical properties were concurrently measured to evaluate the use of optics to improve future sampling coverage in coastal regions. Results indicate peak chlorophyll biomass tracked …


Exogenous Vasotocin Alters Aggression During Agonistic Exchanges In Male Amargosa River Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Gabrielle A. Nevitt Dec 2004

Exogenous Vasotocin Alters Aggression During Agonistic Exchanges In Male Amargosa River Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Pupfishes in the Death Valley region have rapidly differentiated in social behaviors since their isolation in a series of desert streams, springs, and marshes less than 20,000 years ago. These habitats can show dramatic fluctuations in ecological conditions, and pupfish must cope with the changes by plastic physiological and behavioral responses. Recently, we showed differences among some Death Valley populations in brain expression of arginine vasotocin (AVT). As AVT regulates both hydromineral balance and social behaviors in other taxa, these population differences may indicate adaptive changes in osmoregulatory and/or behavioral processes. To test whether AVT is relevant for behavioral shifts …


Identification And Phenotypic Characterization Of The Cell-Division Protein Cdpa, Eric Altermann, B. Logan Buck, Raul Cano, Todd R. Klaenhammer Nov 2004

Identification And Phenotypic Characterization Of The Cell-Division Protein Cdpa, Eric Altermann, B. Logan Buck, Raul Cano, Todd R. Klaenhammer

Biological Sciences

Analysis of the automated computer annotation of the early draft phase genome of Lactobacillus acidophilus NCFM revealed the previously discovered S-layer gene slpA and an additional partial ORF with weak similarities to S-layer proteins. The entire gene was sequenced to reveal a 1799-bp gene coding for 599 amino acids with a calculated molecular mass of 64.8 kDa. No transcription or translation signals could be determined in close proximity to the 5′-region. However, a strong putative terminator with a free energy of −16.84 kcal/mol was identified directly downstream of the gene. A PSI-Blast analysis showed similarities to members of S-layer proteins, …


Application Of Genotypic And Phenotypic Analyses To Commercial Probiotic Strain Identity And Relatedness, P. S. M. Yeung, Christopher L. Kitts, Phillip S. Tong, M. E. Sanders Nov 2004

Application Of Genotypic And Phenotypic Analyses To Commercial Probiotic Strain Identity And Relatedness, P. S. M. Yeung, Christopher L. Kitts, Phillip S. Tong, M. E. Sanders

Biological Sciences

Aims: The objective of this study was to generate strain-specific genomic patterns of a bank of 67 commercial and reference probiotic strains, with a focus on probiotic lactobacilli.
Methods and Results: Pulsed-field gel electrophoresis (PFGE) was used as the primary method for strain differentiation. This method was compared with carbohydrate fermentation analysis. To supplement visual comparison, PFGE patterns were analysed quantitatively by cluster analysis using unweighted pair group method with arithmetic averages. SmaI, NotI and XbaI were found to effectively generate clear and easy-to-interpret PFGE patterns of a range of probiotic strains. Some probiotic strains from different sources shared highly …


Sex Differences In Metabolic Rates In Field Crickets And Their Dipteran Parasitoids, Gita R. Kolluru, Mark A. Chappell, Marlene Zuk Nov 2004

Sex Differences In Metabolic Rates In Field Crickets And Their Dipteran Parasitoids, Gita R. Kolluru, Mark A. Chappell, Marlene Zuk

Biological Sciences

Sex differences in metabolic rate (MR) can result from dimorphism in the performance of energetically demanding activities. Male crickets (Teleogryllus oceanicus) engage in costly calling and aggressive activity not performed by females. Consistent with this difference, we found higher maximal MR, factorial scope, and fat content in males than females. T. oceanicus song is also costly because it attracts the parasitoid fly Ormia ochracea. Parasitized crickets had reduced maximal MR consistent with a metabolic cost to harboring larvae. This cost was greater for females, either because females invest more heavily into reproduction at the expense of metabolic …


Alteration Of The Food Web Along The Antarctic Peninsula In Response To A Regional Warming Trend, Mark A. Moline, Herve Claustre, Thomas K. Frazer, Oscar Schofield, Maria Vernet Nov 2004

Alteration Of The Food Web Along The Antarctic Peninsula In Response To A Regional Warming Trend, Mark A. Moline, Herve Claustre, Thomas K. Frazer, Oscar Schofield, Maria Vernet

Biological Sciences

In the nearshore coastal waters along the Antarctic Peninsula, a recurrent shift in phytoplankton community structure, from diatoms to cryptophytes, has been documented. The shift was observed in consecutive years (1991–1996) during the austral summer and was correlated in time and space with glacial melt-water runoff and reduced surface water salinities. Elevated temperatures along the Peninsula will increase the extent of coastal melt-water zones and the seasonal prevalence of cryptophytes. This is significant because a change from diatoms to cryptophytes represents a marked shift in the size distribution of the phytoplankton community, which will, in turn, impact the zooplankton assemblage. …


Application Of Genotypic And Phenotypic Analyses To Commerical Probiotic Strain Identity And Relatedness, P.S.M. Yeung, C. L. Kitts, R. Cano, P. Tong Nov 2004

Application Of Genotypic And Phenotypic Analyses To Commerical Probiotic Strain Identity And Relatedness, P.S.M. Yeung, C. L. Kitts, R. Cano, P. Tong

Biological Sciences

Aims: The objective of this study was to generate strain-specific genomic patterns of a bank of 67 commercial and reference probiotic strains, with a focus on probiotic lactobacilli.

Methods and Results: Pulsed-field gel electrophoresis (PFGE) was used as the primary method for strain differentiation. This method was compared with carbohydrate fermentation analysis. To supplement visual comparison, PFGE patterns were analysed quantitatively by cluster analysis using unweighted pair group method with arithmetic averages. SmaI, NotI and XbaI were found to effectively generate clear and easy-to-interpret PFGE patterns of a range of probiotic strains. Some probiotic strains from different sources …


Complete Genomic Sequence Of Bacteriophage B3, A Mu-Like Phage Of Pseudomonas Aeruginosa, Michael D. Braid, Jennifer L. Silhavy, Christopher L. Kitts, Raul J. Cano, Martha M. Howe Oct 2004

Complete Genomic Sequence Of Bacteriophage B3, A Mu-Like Phage Of Pseudomonas Aeruginosa, Michael D. Braid, Jennifer L. Silhavy, Christopher L. Kitts, Raul J. Cano, Martha M. Howe

Biological Sciences

Bacteriophage B3 is a transposable phage of Pseudomonas aeruginosa. In this report, we present the complete DNA sequence and annotation of the B3 genome. DNA sequence analysis revealed that the B3 genome is 38,439 bp long with a G+C content of 63.3%. The genome contains 59 proposed open reading frames (ORFs) organized into at least three operons. Of these ORFs, the predicted proteins from 41 ORFs (68%) display significant similarity to other phage or bacterial proteins. Many of the predicted B3 proteins are homologous to those encoded by the early genes and head genes of Mu and Mu-like prophages found …


Evidence That Thyroid Hormone Induces Olfactory Cellular Proliferation In Salmon During A Sensitive Period For Imprinting, Sean C. Lema, Gabrielle A. Nevitt Oct 2004

Evidence That Thyroid Hormone Induces Olfactory Cellular Proliferation In Salmon During A Sensitive Period For Imprinting, Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Salmon have long been known to imprint and home to natal stream odors, yet the mechanisms driving olfactory imprinting remain obscure. The timing of imprinting is associated with elevations in plasma thyroid hormone levels, with possible effects on growth and proliferation of the peripheral olfactory system. Here, we begin to test this idea by determining whether experimentally elevated plasma levels of 3,5,3′-triiodothyronine (T3) influence cell proliferation as detected by the 5-bromo-2′-deoxyuridine (BrdU) cell birth-dating technique in the olfactory epithelium of juvenile coho salmon (Oncorhynchus kisutch). We also explore how natural fluctuations in thyroxine (T4) …


Identification And Inactivation Of Genetic Loci Involved With Lactobacillus Acidophilus Acid Tolerance, M. Andrea Azcarate-Peril, Eric Altermann, Rebecca L. Hoover- Fitzula, Raul J. Cano, Todd R. Klaenhammer Sep 2004

Identification And Inactivation Of Genetic Loci Involved With Lactobacillus Acidophilus Acid Tolerance, M. Andrea Azcarate-Peril, Eric Altermann, Rebecca L. Hoover- Fitzula, Raul J. Cano, Todd R. Klaenhammer

Biological Sciences

Amino acid decarboxylation-antiporter reactions are one of themost important systems for maintaining intracellular pH betweenphysiological limits under acid stress. We analyzed the Lactobacillusacidophilus NCFM complete genome sequence and selected fouropen reading frames with similarities to genes involved withdecarboxylation reactions involved in acid tolerance in severalmicroorganisms. Putative genes encoding an ornithine decarboxylase,an amino acid permease, a glutamate -aminobutyrate antiporter,and a transcriptional regulator were disrupted by insertionalinactivation. The ability of L. acidophilus to survive low-pHconditions, such as those encountered in the stomach or fermenteddairy foods, was investigated and compared to the abilitiesof early- and late-stationary-phase cells of the mutants bychallenging them with …


Deriving In Situ Phytoplankton Absorption For Bio-Optical Productivity Models In Turbid Waters, Christina Orrico, Matthew J. Oliver, Oscar Schofield, Trisha Bergmann, Scott Glenn, Mark A. Moline Jul 2004

Deriving In Situ Phytoplankton Absorption For Bio-Optical Productivity Models In Turbid Waters, Christina Orrico, Matthew J. Oliver, Oscar Schofield, Trisha Bergmann, Scott Glenn, Mark A. Moline

Biological Sciences

As part of Hyperspectral Coupled Ocean Dynamics Experiment, a high-resolution hydrographic and bio-optical data set was collected from two cabled profilers at the Long-Term Ecosystem Observatory (LEO). Upwelling-and downwelling-favorable winds and a buoyant plume from the Hudson River induced large changes in hydrographic and optical structure of the water column. An absorption inversion model estimated the relative abundance of phytoplankton, colored dissolved organic matter (CDOM) and detritus, as well as the spectral exponential slopes of CDOM and detritus from in situ WET Labs nine-wavelength absorption/attenuation meter (ac-9) absorption data. Derived optical weights were proportional to the parameter concentrations and allowed …


The New Age Of Hyperspectral Oceanography, Grace Chang, Kevin Mahoney, Amanda Briggs-Whitmire, David Kohler, Curtis Mobley, Marlon Lewis, Mark A. Moline, Emmanuel Boss, Minsu Kim, William Philpot, Tommy Dickey Jun 2004

The New Age Of Hyperspectral Oceanography, Grace Chang, Kevin Mahoney, Amanda Briggs-Whitmire, David Kohler, Curtis Mobley, Marlon Lewis, Mark A. Moline, Emmanuel Boss, Minsu Kim, William Philpot, Tommy Dickey

Biological Sciences

No abstract provided.


Watercolors In The Coastal Zone: What Can We See?, Oscar Schofield, Robert A. Arnone, W. Paul Bissett, Tommy D. Dickey, Curtis O. Davis, Zoe Finkel, Matthew Oliver, Mark A. Moline Jun 2004

Watercolors In The Coastal Zone: What Can We See?, Oscar Schofield, Robert A. Arnone, W. Paul Bissett, Tommy D. Dickey, Curtis O. Davis, Zoe Finkel, Matthew Oliver, Mark A. Moline

Biological Sciences

No abstract provided.


Diploid And Polyploid Cytotype Distribution In Melampodium Cinereum And M. Leucanthum (Asteraceae, Heliantheae), Tod F. Stuessy, Hanna Weiss-Schneeweiss, David J. Keil Jun 2004

Diploid And Polyploid Cytotype Distribution In Melampodium Cinereum And M. Leucanthum (Asteraceae, Heliantheae), Tod F. Stuessy, Hanna Weiss-Schneeweiss, David J. Keil

Biological Sciences

Previous chromosomal studies within Melampodium (Asteraceae, Heliantheae) of Mexico and Central America have documented chromosome numbers n = 9, 10, 11, 12, 18, 20, 23, 25 ± 1, 27, 30, and 33. Some species also have been shown to exhibit infra-and interpopulational polyploidy. The presence of cytotype mixtures is especially pronounced in the white-rayed complex, which occurs in the southwestern United States and adjacent Mexico. This group includes M. cinereum (n = 10 and 20), M. leucanthum (n = 10 and 20), and M. argophyllum (n = 30). Cytotype distribution has been newly analyzed in 415 plants from 152 populations …


Variability In Measured And Modelled Remote Sensing Reflectance For Coastal Waters At Leo-5, Sasha Tozzi, Oscar Schofield, Trisha Bergmann, Mark A. Moline, Robert Arnone Apr 2004

Variability In Measured And Modelled Remote Sensing Reflectance For Coastal Waters At Leo-5, Sasha Tozzi, Oscar Schofield, Trisha Bergmann, Mark A. Moline, Robert Arnone

Biological Sciences

A large database of in situ bio-optical measurements were collected at the LEO-15 (Long-term Ecosystem Observatory) off the southern coast of New Jersey, USA. The data were used to quantify the impact of coastal upwelling on near-shore bulk apparent (AOP) and inherent (IOP) optical properties. There was good qualitative agreement between the AOPs and IOPs in space and time. The measured IOPs were used as inputs to the Hydrolight radiative transfer model (RTE). Estimated spectral AOPs from the RTE were strongly correlated (generally R2>0.80) to measured AOPs. If optical closure between in-water measurements was achieved then the RTE …


Variability In Spectral Backscatter Estimated From Satellites And Its Relation To In Situ Measurements In Optically Complex Coastal Waters, Mark A. Moline, Robert Arnone, Trisha Bergmann, Scott Glenn, Matthew J. Oliver, Cristina Orrico, Oscar Schofield, Sasha Tozzi Apr 2004

Variability In Spectral Backscatter Estimated From Satellites And Its Relation To In Situ Measurements In Optically Complex Coastal Waters, Mark A. Moline, Robert Arnone, Trisha Bergmann, Scott Glenn, Matthew J. Oliver, Cristina Orrico, Oscar Schofield, Sasha Tozzi

Biological Sciences

A large database of in situ bio-optical measurements was collected at the Long-term Ecosystem Observatory off the southern coast of New Jersey, USA. In part, the research effort focused on reconciling in situ estimates with satellite-derived estimates of the inherent optical properties (IOP). At 442 nm, in situ absorption values ranged from less than 0.2 to over 1.5 inverse metres. Satellite estimates of backscatter ranged from 0.002 to 0.03 inverse metres at 442 nm and showed significant variability in time and space during July 1999, reflecting the recurrent high frequency events that characterize the region—wind-mixing, storms and coastal upwelling. Despite …


Micrococcus Luteus - Survival In Amber, C. L. Greenblatt, J. Baum, B. Y. Klein, S. Nachshon, V. Koltunov, R. J. Cano Apr 2004

Micrococcus Luteus - Survival In Amber, C. L. Greenblatt, J. Baum, B. Y. Klein, S. Nachshon, V. Koltunov, R. J. Cano

Biological Sciences

A growing body of evidence now supports the isolation of microorganisms from ancient materials. However, questions about the stringency of extraction methods and the genetic relatedness of isolated organisms to their closest living relatives continue to challenge the authenticity of these ancient life forms. Previous studies have successfully isolated a number of spore-forming bacteria from organic and inorganic deposits of considerable age whose survival is explained by their ability to enter suspended animation for extended periods of time. However, despite a number of putative reports, the isolation of non-spore-forming bacteria and an explanation for their survival have remained enigmatic. Here …


Bayesian Statistics For Biological Data: Pedigree Analysis, William D. Stansfield, Matthew A. Carlton Mar 2004

Bayesian Statistics For Biological Data: Pedigree Analysis, William D. Stansfield, Matthew A. Carlton

Biological Sciences

No abstract provided.


Bacterial Succession In A Petroleum Land Treatment Unit, Christopher W. Kaplan, Christopher L. Kitts Mar 2004

Bacterial Succession In A Petroleum Land Treatment Unit, Christopher W. Kaplan, Christopher L. Kitts

Biological Sciences

Bacterial community dynamics were investigated in a land treatment unit (LTU) established at a site contaminated with highly weathered petroleum hydrocarbons in the C(10) to C(32) range. The treatment plot, 3,000 cubic yards of soil, was supplemented with nutrients and monitored weekly for total petroleum hydrocarbons (TPH), soil water content, nutrient levels, and aerobic heterotrophic bacterial counts. Weekly soil samples were analyzed with 16S rRNA gene terminal restriction fragment (TRF) analysis to monitor bacterial community structure and dynamics during bioremediation. TPH degradation was rapid during the first 3 weeks and slowed for the remainder of the 24-week project. A sharp …


Fossil Tuna Vertebrae Punctured By Istiophorid Billfishes, Vincent P. Schneider, Harry L. Fierstine Mar 2004

Fossil Tuna Vertebrae Punctured By Istiophorid Billfishes, Vincent P. Schneider, Harry L. Fierstine

Biological Sciences

No abstract provided.


In Situ Cardiac Performance Of Pacific Bluefin Tuna Hearts In Response To Acute Temperature Change, Jason M. Blank, Jeffery M. Morrissette, Ana M. Landeira-Fernandez, Susanna B. Blackwell, Thomas D. Williams, Barbara A. Block Feb 2004

In Situ Cardiac Performance Of Pacific Bluefin Tuna Hearts In Response To Acute Temperature Change, Jason M. Blank, Jeffery M. Morrissette, Ana M. Landeira-Fernandez, Susanna B. Blackwell, Thomas D. Williams, Barbara A. Block

Biological Sciences

This study reports the cardiovascular physiology of the Pacific bluefin tuna (Thunnus orientalis) in an in situ heart preparation. The performance of the Pacific bluefin tuna heart was examined at temperatures from 30°C down to 2°C. Heart rates ranged from 156 beats min–1 at 30°C to 13 beats min–1 at 2°C. Maximal stroke volumes were 1.1 ml kg–1 at 25°C and 1.3 ml kg–1 at 2°C. Maximal cardiac outputs were 18.1 ml kg–1 min–1 at 2°C and 106 ml kg–1 min–1 at 25°C. These data indicate that cardiovascular function in …


A Comparison Between Point- And Semi-Continuous Sampling For Assessing Body Temperature In A Free-Ranging Ectotherm, Emily N. Taylor, Dale F. Denardo, Michael A. Malawy Feb 2004

A Comparison Between Point- And Semi-Continuous Sampling For Assessing Body Temperature In A Free-Ranging Ectotherm, Emily N. Taylor, Dale F. Denardo, Michael A. Malawy

Biological Sciences

We used intracoelomically implanted temperature dataloggers to obtain semi-continuous body temperature data and establish monthly thermal profiles for free-ranging rattlesnakes. We mimicked random and non-random point-sampling methods by selecting a single daily data point from all values or from restricted times of day to reflect common point-sampling constraints. Thermal profiles generated from point-sampling differed from those generated from semi-continuous sampling, and this difference was more apparent when point-sampling was non-random. We conclude that semi-continuous sampling provides a better estimate of thermal profiles, and that point-sampling methods are highly sensitive to deviations from true randomness.


Variation In Vasotocin Immunoreactivity In The Brain Of Recently Isolated Populations Of A Death Valley Pupfish, Cyprinodon Nevadensis, Sean C. Lema, Gabrielle A. Nevitt Feb 2004

Variation In Vasotocin Immunoreactivity In The Brain Of Recently Isolated Populations Of A Death Valley Pupfish, Cyprinodon Nevadensis, Sean C. Lema, Gabrielle A. Nevitt

Biological Sciences

Pupfishes in the Death Valley region of California and Nevada comprise a monophyletic group of populations that became isolated in remote streams and springs over the past 20,000 years. These aquatic habitats show considerable ecological diversity, and allopatric populations have evolved differences in morphology and behavior. Here we investigated whether the divergence of pupfish populations in Death Valley might be associated with changes in arginine vasotocin (AVT). We used immunocytochemistry to compare the expression of AVT in the brain of Amargosa pupfish (Cyprinodon nevadensis) from two Death Valley populations: (1) the Amargosa River—a highly variable desert stream containing …


Hamlet Revisited: How Evolution Really Works, William D. Stansfield Jan 2004

Hamlet Revisited: How Evolution Really Works, William D. Stansfield

Biological Sciences

Delves into the artificial programs that are merely metaphors for the processes of organic evolution. Relation of this organic evolution with the phrases in the play "Hamlet" of Shakespeare; Disadvantage of using these metaphors as educational tools; Definition of various kinds of patterns for evolution.


Sex–Specific Effects Of Carotenoid Intake On The Immunological Response To Allografts In Guppies (Poecilia Reticulata), Gregory F. Grether, Shinji Kasahara, Gita R. Kolluru, Edwin L. Cooper Jan 2004

Sex–Specific Effects Of Carotenoid Intake On The Immunological Response To Allografts In Guppies (Poecilia Reticulata), Gregory F. Grether, Shinji Kasahara, Gita R. Kolluru, Edwin L. Cooper

Biological Sciences

Rarely are the evolutionary origins of mate preferences known, but, recently, the preference of female guppies (Poecilia reticulata) for males with carotenoid‐based sexual coloration has been linked to a sensory bias that may have originally evolved for detecting carotenoid‐rich fruits. If carotenoids enhance the immune systems of these fishes, as has been suggested for other species, this could explain the origin of the attraction to orange fruits as well as the maintenance of the female preference for orange males. We used the classic immunological technique of tissue grafting to assay a component of the immune response of guppies …


Individual Colour Patches As Multicomponent Signals, Gregory F. Grether, Gita R. Kolluru, Karen Nersissian Jan 2004

Individual Colour Patches As Multicomponent Signals, Gregory F. Grether, Gita R. Kolluru, Karen Nersissian

Biological Sciences

Colour patches are complex traits, the components of which may evolve independently through a variety of mechanisms. Although usually treated as simple, two-dimensional characters and classified as either structural or pigmentary, in reality colour patches are complicated, three-dimensional structures that often contain multiple pigment types and structural features. The basic dermal chromatophore unit of fishes, reptiles and amphibians consists of three contiguous cell layers. Xanthophores and erythrophores in the outermost layer contain carotenoid and pteridine pigments that absorb short-wave light; iridophores in the middle layer contain crystalline platelets that reflect light back through the xanthophores; and melanophores in the basal …


Bioinformatic Approaches For Objective Detection Of Water Masses On Continental Shelves, Mark A. Moline, Matthew J. Oliver, Scott Glenn, Josh T. Kohut, Andrew J. Irwin, Oscar M. Schofield, Paul W. Bissett Jan 2004

Bioinformatic Approaches For Objective Detection Of Water Masses On Continental Shelves, Mark A. Moline, Matthew J. Oliver, Scott Glenn, Josh T. Kohut, Andrew J. Irwin, Oscar M. Schofield, Paul W. Bissett

Biological Sciences

As part of the 2001 Hyper Spectral Coupled Ocean Dynamics Experiment, sea surface temperature and ocean color satellite imagery were collected for the continental shelf of the Mid-Atlantic Bight. These images were used to develop a water mass analysis and classification scheme that objectively describes the locations of water masses and their boundary locations. This technique combines multivariate cluster analysis with a newly developed genetic expression algorithm to objectively determine the number of water types in the region on the basis of ocean color and sea surface temperature measurements. Then, through boundary analysis of the water types identified, the boundaries …


New Taxa And New Combinations In North American Cirsium (Asteraceae: Cardueae), David J. Keil Jan 2004

New Taxa And New Combinations In North American Cirsium (Asteraceae: Cardueae), David J. Keil

Biological Sciences

Six new varieties are proposed in North American Cirsium (Asteraceae: Cardueae): C. arizonicum (A. Gray) Petrak var. tenuisectum D.J. Keil var. nov., C. eatonii (A. Gray) B.L. Rob. var. viperinum D.J. Keil, var. nov., C. edule Nutt. var. wenatchense D.J. Keil, var. nov., C. occidentale (Nutt.) Jeps. var. lucianum D.J. Keil, var. nov., C. scariosum Nutt. var. robustum D.J. Keil, var. nov., C. scariosum Nutt. var. toiyabense D.J. Keil, var. nov. Additionally, twenty new combinations are presented: C. arizonicum (A. Gray) Petrak var. bipinnatum (Eastw.) D.J. Keil, comb. nov., C. arizonicum (A. Gray) Petrak var. chellyense (R.J. Moore & Frankton) …


Physical Forcing Of Phytoplankton Community Structure And Primary Production In Continental Shelf Waters Of The Western Antarctic Peninsula, Barbara B. Prezelin, Eileen E. Hofmann, Mark A. Moline, John M. Klinck Jan 2004

Physical Forcing Of Phytoplankton Community Structure And Primary Production In Continental Shelf Waters Of The Western Antarctic Peninsula, Barbara B. Prezelin, Eileen E. Hofmann, Mark A. Moline, John M. Klinck

Biological Sciences

Analyses of a multidisciplinary data set, collected in continental shelf waters of the Western Antarctic Peninsula (WAP) during austral summer of January 1993, identified a previously unrecognized forcing mechanism that sets up a physical and chemical structure that supports and assures site-specific diatom-dominated communities and enhanced biological production (Prézelin et al., 2000). This forcing is active when the southern boundary of the Antarctic Circumpolar Current (ACC) flows along the shelf edge, thereby facilitating onshelf bottom intrusions of nutrient-rich Upper Circumpolar Deep Water (UCDW), which then is upwelled or mixed into the upper water column. At times or locations where UCDW …


Biogeochemical Impact Of Summertime Coastal Upwelling On The New Jersey Shelf, Scott Glenn, Robert Arnone, Trisha Bergmann, Paul W. Bissett, Michael Crowley, Jay Cullen, Joe Gryzmski, Dale Haidvogel, Josh Kohut, Mark A. Moline, Mathew Oliver, Cris Orrico, Robert Sherrell, Tony Song, Alan Weidemann, Robert Chant, Oscar Schofield Jan 2004

Biogeochemical Impact Of Summertime Coastal Upwelling On The New Jersey Shelf, Scott Glenn, Robert Arnone, Trisha Bergmann, Paul W. Bissett, Michael Crowley, Jay Cullen, Joe Gryzmski, Dale Haidvogel, Josh Kohut, Mark A. Moline, Mathew Oliver, Cris Orrico, Robert Sherrell, Tony Song, Alan Weidemann, Robert Chant, Oscar Schofield

Biological Sciences

The alternative hypothesis that observed regions of recurrent hypoxia on the New Jersey inner shelf are more related to coastal upwelling than riverine inputs of nutrients was investigated through a series of multidisciplinary research programs beginning in 1993. The largest variations in ocean temperatures along the New Jersey coast, other than seasonal, are found to be caused by episodic summertime upwelling events driven by southwesterly winds associated with the atmospheric Bermuda High. Off the southern coast of New Jersey, topographic variations associated with ancient river deltas cause upwelled water to evolve into an alongshore line of recurrent upwelling centers that …