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Full-Text Articles in Life Sciences

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan Bond, John Stephens, Daniel Pondella, James Allen, Mark Helvey May 2013

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan Bond, John Stephens, Daniel Pondella, James Allen, Mark Helvey

Alan B. Bond

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …


Access To Another Mind: Naturalistic Theories Require Naturalistic Data, Mark A. Krause, Gordon Burghardt Dec 1999

Access To Another Mind: Naturalistic Theories Require Naturalistic Data, Mark A. Krause, Gordon Burghardt

Gordon Burghardt

If there is to be a natural theory of consciousness that would satisfy both philosophers and scientists, it must be based on naturalistic data and minimal clutter accumulated from semantic arguments. Carruthers offers a 'natural' theory of consciousness that is rather myopic. To explore the evolutionary basis of consciousness, a natural theory should include comparative psychological and neurological data that encompass nonlinguistic measures. Such an approach could provide a clearer picture of the adaptive function, mechanisms, and origins of consciousness.


Analysis Of Age And Growth In Two Eastern Pacific Groupers (Serranidae: Epinephelinae), Matthew Craig, Daniel Pondella, John Hafner Oct 1999

Analysis Of Age And Growth In Two Eastern Pacific Groupers (Serranidae: Epinephelinae), Matthew Craig, Daniel Pondella, John Hafner

Daniel Pondella

In an attempt to characterize species specific-growth rates of two Eastern Pacific groupers, individuals from two sympatric species, Epinephelus labriformis (n = 173), and Cephalopholis panamensis (n = 127), were collected at various localities in Mexico and the Galápagos archipelago in 1997 and 1998. Sagittal otoliths were removed, and age of each individual was determined by direct visual inspection of annuli present following sectioning. Length/weight relationships were determined, and growth curves were generated using the von Bertalanffy growth model. The two species demonstrated similar growth rates, yet, as determined by the von Bertalanffy parameters, E. labriformis tended towards a larger …


Phd Thesis (Doctorat De Spécialité): Université De Ouagadougou, 1999. Dr. Mamoudou H. Dicko. Purification Et Propriétés Physico-Chimiques Des Enzymes De Curculigo Pilosa, Gladiolus Klattianus Et Boscia Senegalensis Catalysant L'Hydrolyse Des Polysaccharides (Amidon Et Béta-Glucanes), Mamoudou H. Dicko Prof. Jun 1999

Phd Thesis (Doctorat De Spécialité): Université De Ouagadougou, 1999. Dr. Mamoudou H. Dicko. Purification Et Propriétés Physico-Chimiques Des Enzymes De Curculigo Pilosa, Gladiolus Klattianus Et Boscia Senegalensis Catalysant L'Hydrolyse Des Polysaccharides (Amidon Et Béta-Glucanes), Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The objective of this study was the research of novel and inexpensive sources of polysaccharides degrading enzymes such as amylases and glucanases from local plants in order to justify their biotechnological applications. The isolation of two l3-amylases and an endo-1,3-ß-D-glucanase was reached using common protein purification methods such as buffer extraction, ammonium sulfate fractionation, ionexchange and gel filtration chromatographies. The methods used were simple and easily reproducible, suggesting the possibilfty of large-scale production. ln the crude extract of Curculigo pilosa tuber, only ß-amylase was detected as starch degrading enzyme and its activity was approximately 282 Uig of fresh material. The …


Recovery And Viability Of Edwardsiella Ictaluri From Great Blue Herons Ardea Herodias Fed E. Ictaluri-Infected Channel Catfish Lctalurus Punctatus Fingerlings, Paul R. Waterstrat, Brian S. Dorr, James F. Glahn, Mark E. Tobin Mar 1999

Recovery And Viability Of Edwardsiella Ictaluri From Great Blue Herons Ardea Herodias Fed E. Ictaluri-Infected Channel Catfish Lctalurus Punctatus Fingerlings, Paul R. Waterstrat, Brian S. Dorr, James F. Glahn, Mark E. Tobin

Brian S Dorr

No abstract provided.


A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Daniel J. Pondella Ii, James M. Allen, Mark Helvey Feb 1999

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan B. Bond, John S. Stephens, Daniel J. Pondella Ii, James M. Allen, Mark Helvey

Daniel Pondella

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …


Avian Prey-Dropping Behavior. I. The Effects Of Prey Characteristics And Prey Loss, Paul V. Switzer, Daniel A. Cristol Jan 1999

Avian Prey-Dropping Behavior. I. The Effects Of Prey Characteristics And Prey Loss, Paul V. Switzer, Daniel A. Cristol

Paul V. Switzer

No abstract provided.


Adapt Globally, Act Locally: The Effect Of Selective Sweeps On Bacterial Sequence Diversity, J. Majewski, Frederick Cohan Jan 1999

Adapt Globally, Act Locally: The Effect Of Selective Sweeps On Bacterial Sequence Diversity, J. Majewski, Frederick Cohan

Frederick M. Cohan

No abstract provided.


Revegetating Desert Plant Communities, David A. Bainbridge Jan 1999

Revegetating Desert Plant Communities, David A. Bainbridge

David A Bainbridge

Desert revegetation is possible but not easy. Careful attention to plant production (root:shoot), site prep, planting, irrigation and aftercare can lead to good survival even under extreme desert conditions. Cost per survivor is a critical consideration.


Soil Pitting For Revegetation, David A. Bainbridge Jan 1999

Soil Pitting For Revegetation, David A. Bainbridge

David A Bainbridge

Soil pitting provides many benefits in ecological restoration of degraded lands. The pits capture rainwater, trap seeds and soil symbionts and protect seedlings from windblast.


Soil Treatment For Restoration Projects, David A. Bainbridge Jan 1999

Soil Treatment For Restoration Projects, David A. Bainbridge

David A Bainbridge

Soil treatment is a critical step in restoration projects. When soil problems are ignored restoration projects fail. Erosion, compaction, limited infiltration and other problems can make a site very different from its historic function and structure. Treatment can be done with equipment or by hand and will greatly improve chances for success.


Soil Amino Acid Utilization Among Species Of The Cyperaceae: Plant And Soil Processes, Ted K. Raab, David A. Lipson, Steven K. Scmidt, Russ K. Monson Jan 1999

Soil Amino Acid Utilization Among Species Of The Cyperaceae: Plant And Soil Processes, Ted K. Raab, David A. Lipson, Steven K. Scmidt, Russ K. Monson

Ted K. Raab

Amino acids are released during the decomposition of soil organic matter and have been shown to be utilized as a nitrogen source by some non-mycorrhizal species in the family Cyperaceae (the sedge family). Twelve out of 13 Cyperaceae species examined in the current study were capable of absorbing soil amino acids in the non-mycorrhizal state. With two exceptions (two species in the genus Kobresia), species from subalpine or alpine habitats exhibited lower rates of total nitrogen uptake compared to species from more temperate habitats, which is possibly explained by lower growth rates in the alpine and subalpine species and a …


Variation In Competitive Abilities Of Plants And Microbes For Specific Amino Acids, David A. Lipson, Ted K. Raab, Steven K. Schmidt, Russ K. Monson Jan 1999

Variation In Competitive Abilities Of Plants And Microbes For Specific Amino Acids, David A. Lipson, Ted K. Raab, Steven K. Schmidt, Russ K. Monson

Ted K. Raab

Microbes are assumed to possess strong competitive advantages over plants for uptake of nutrients from the soil. The finding that non-mycorrhizal plants can obtain a significant fraction of their N requirement from soil amino acids contradicts this assumption. The amino acid glycine (Gly) has been used as a model amino acid in many recent studies. Our preliminary studies showed that Gly was a poor substrate for microbial growth compared to other amino acids. We tested the hypothesis that the alpine sedge Kobresia myosuroides competes better for Gly than for other amino acids because of decreased microbial demand for this compound. …


The Effect Of Water Level Management On The Soils And Vegetation Of Two Coastal Louisiana Marshes, Brian J. Wilsey, K. M. Flynn, I. A. Mendelssohn Jan 1999

The Effect Of Water Level Management On The Soils And Vegetation Of Two Coastal Louisiana Marshes, Brian J. Wilsey, K. M. Flynn, I. A. Mendelssohn

Brian J. Wilsey

Wetland degradation and loss is the result of a combination of natural causes and anthropogenic activities and is a serious problem in coastal Louisiana, where approximately 80% of the total US coastal wetland loss since the 1930’s has occurred. One method currently used to address this wetland loss problem is structural marsh management,which is the use of levees and water control structures to control hydroperiod. The effects of structural marsh management on two managed marshes in Southern Louisiana (Unit 4 of the Rockefeller Wildlife Refuge and the Fina LaTerre Mitigation Bank) were evaluated by comparing the soils and the dominant …


The Genetics And Evolution Of The Mariner Transposable Element In Drosophila Simulans: Worldwide Distribution And Experimental Population Dynamics, Amy L. Russell, R. C. Woodruff Dec 1998

The Genetics And Evolution Of The Mariner Transposable Element In Drosophila Simulans: Worldwide Distribution And Experimental Population Dynamics, Amy L. Russell, R. C. Woodruff

Amy L. Russell

We have studied both the frequency and biogeographical distribution of the transposable DNA element mariner in natural populations of Drosophila simulans and the short-term evolutionary characteristics of mariner in experimental populations. The mariner element has been identified in natural populations of D. simulans from Africa, Europe, the Middle East, Japan, Australia, several Pacific islands, North America, and South America. Only four lines out of 296 were devoid of active mariner elements, as measured by the presence of functional mariner transposase. A slight correlation was found between the latitudinal coordinate of the collection sites and the level of mariner activity in …


Relationship Between The Bacillus Subtilis Clades Associated With Strains 168 And W23: A Proposal For B. Subtilis Subsp. Subtilis And B. Subtilis Subsp. Spizizenii, L. K. Nakamura, M. S. Roberts, Frederick M. Cohan Dec 1998

Relationship Between The Bacillus Subtilis Clades Associated With Strains 168 And W23: A Proposal For B. Subtilis Subsp. Subtilis And B. Subtilis Subsp. Spizizenii, L. K. Nakamura, M. S. Roberts, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


Dna Sequence Similarity Requirements For Interspecific Recombination In Bacillus, J. Majewski, Frederick M. Cohan Dec 1998

Dna Sequence Similarity Requirements For Interspecific Recombination In Bacillus, J. Majewski, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.