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Full-Text Articles in Life Sciences

Development Of Real-Time Pcr Assays For Rapid Detection Of Pfiesteria Piscicida And Related Dinoflagellates, Torstein Tengs Nov 2000

Development Of Real-Time Pcr Assays For Rapid Detection Of Pfiesteria Piscicida And Related Dinoflagellates, Torstein Tengs

Dr. Torstein Tengs

Pfiesteria complex species are heterotrophic and mixotrophic dinoflagellates that have been recognized as harmful algal bloom species associated with adverse fish and human health effects along the East Coast of North America, particularly in its largest (Chesapeake Bay in Maryland) and second largest (Albermarle- Pamlico Sound in North Carolina) estuaries. In response to impacts on human health and the economy, monitoring programs to detect the organism have been implemented in affected areas. However, until recently, specific identification of the two toxic species known thus far, Pfiesteria piscicida and P. shumwayae (sp. nov.), required scanning electron microscopy (SEM). SEM is a ...


Effects Of Willows (Salix Brachycarpa) On Populations Of Salicylate-Mineralizing Microorganisms In Alpine Soils, Steven K. Schmidt, David A. Lipson, Ted K. Raab Sep 2000

Effects Of Willows (Salix Brachycarpa) On Populations Of Salicylate-Mineralizing Microorganisms In Alpine Soils, Steven K. Schmidt, David A. Lipson, Ted K. Raab

Ted K. Raab

We used the substrate-induced growth-response (SIGR) method to quantify salicylate-mineralizing microbes and total microbial biomass in soils from under willows (Salix brachycarpa) and in surrounding meadows dominated by the sedge Kobresia myosuroides. Willows had a strong effect on the biomass of salicylate-mineralizing microbes in both years of this study. There were always higher biomass levels of salicylate mineralizers in soils from under Salix (4.6–10.1 ug C/ g) than under Kobresia (0.23–0.76 ug/ g). In contrast, total microbial biomass was not significantly different under these plant species in 1996 and was only higher under Salix ...


Phylogenetic Analyses Indicate That The 19'Hexanoyloxy-Fucoxanthin-Containing Dinoflagellates Have Tertiary Plastids Of Haptophyte Origin, Torstein Tengs May 2000

Phylogenetic Analyses Indicate That The 19'Hexanoyloxy-Fucoxanthin-Containing Dinoflagellates Have Tertiary Plastids Of Haptophyte Origin, Torstein Tengs

Dr. Torstein Tengs

The three anomalously pigmented dinoflagellates Gymnodinium galatheanum, Gyrodinium aureolum, and Gymnodinium breve have plastids possessing 199-hexanoyloxy-fucoxanthin as the major carotenoid rather than peridinin, which is characteristic of the majority of the dinoflagellates. Analyses of SSU rDNA from the plastid and the nuclear genome of these dinoflagellate species indicate that they have acquired their plastids via endosymbiosis of a haptophyte. The dinoflagellate plastid sequences appear to have undergone rapid sequence evolution, and there is considerable divergence between the three species. However, distance, parsimony, and maximum-likelihood phylogenetic analyses of plastid SSU rRNA gene sequences place the three species within the haptophyte clade ...


Heteroduplex Mobility Assay-Guided Sequence Discovery: Elucidation Of The Small Subunit (18s) Rdna Sequences Of Pfiesteria Piscicida And Related Dinoflagellates From Complex Algal Culture And Environmental Sample Dna Pools, Torstein Tengs Apr 2000

Heteroduplex Mobility Assay-Guided Sequence Discovery: Elucidation Of The Small Subunit (18s) Rdna Sequences Of Pfiesteria Piscicida And Related Dinoflagellates From Complex Algal Culture And Environmental Sample Dna Pools, Torstein Tengs

Dr. Torstein Tengs

The newly described heterotrophic estuarine dinoflagellate Pfiesteria piscicida has been linked with fish kills in field and laboratory settings, and with a novel clinical syndrome of impaired cognition and memory disturbance among humans after presumptive toxin exposure. As a result, there is a pressing need to better characterize the organism and these associations. Advances in Pfiesteria research have been hampered, however, by the absence of genomic sequence data. We employed a sequencing strategy directed by heteroduplex mobility assay to detect Pfiesteria piscicida 18S rDNA ‘‘signature’’ sequences in complex pools of DNA and used those data as the basis for determination ...


Terminology Work: Tools And Processes That Make A Difference, Uwe Muegge Jan 2000

Terminology Work: Tools And Processes That Make A Difference, Uwe Muegge

Uwe Muegge

Technical texts, i.e., technical literature proper (data sheets, user documentation, scientific publications, etc.), as well as the whole range of medical and legal texts, have one feature in common: Their authors make generous use of: a) words not in common usage, e.g., dongle (a computer hardware device that prevents unauthorized use of protected software); and/or b) words that are in common usage but have a slightly, or even totally, different meaning in the special language, e.g., bug (in the general sense, this means a small insect, but in the computer software field, this is a small ...


Water Fog For Repelling Birds, Larry Clark, Thomas Nachtman, John Hull Jan 2000

Water Fog For Repelling Birds, Larry Clark, Thomas Nachtman, John Hull

Larry Clark

No abstract provided.


Container Substrate Temperatures Affect Mineralization Of Composts, Helen T. Kraus, Robert Mikkelsen, Stuart L. Warren Jan 2000

Container Substrate Temperatures Affect Mineralization Of Composts, Helen T. Kraus, Robert Mikkelsen, Stuart L. Warren

Robert Mikkelsen

Traditional N mineralization studies have been conducted by soil scientists using soils and temperatures found in field production. As temperature, in part, governs the rate of mineralization, and container substrates reach much higher temperatures than do soils, the effect of these elevated temperatures on mineralization must be considered to begin to understand N mineralization in container substrates during production. The N mineralization patterns of three composts [turkey (Meleagris gallopavo) litter, yard waste, and municipal waste] were determined under three temperature regimes (45, 25, and 45/25 °C). More organic N was mineralized from composted turkey litter (CTL) than from municipal ...


Beneficial Use Of Swine By-Products: Opportunities For The Future, Robert Mikkelsen Jan 2000

Beneficial Use Of Swine By-Products: Opportunities For The Future, Robert Mikkelsen

Robert Mikkelsen

No abstract provided.


The Ethics Of Caring And Medical Education, William T. Branch Jr. Md, Macp Jan 2000

The Ethics Of Caring And Medical Education, William T. Branch Jr. Md, Macp

William T.Branch Jr.MD

The ethics of caring, though the subject of much recent discussion by philosophers, has hardly been applied to medical ethics and medical education. Based on receptivity (that is, empathy and compassion) toward and taking responsibility for other persons, the ethics of caring has particular relevance to medicine. Caring guides the physician always to remain the patient's advocate and to maintain the therapeutic relationship when dealing with and resolving ethical dilemmas. This article discusses the philosophy behind the ethics of caring and then explores three issues that arise within its context: receptivity, taking responsibility, and creating an educational environment that ...


Supporting The Moral Development Of Medical Students, William T. Branch Jr. Md, Macp Jan 2000

Supporting The Moral Development Of Medical Students, William T. Branch Jr. Md, Macp

William T.Branch Jr.MD

Philosophers who studied moral development have found that individuals normally progress rapidly in early adulthood from a conventional stage in which they base behavior on the norms and values of those around them to a more principled stage where they identify and attempt to live by personal moral values. Available data suggest that many medical students, who should be in this transition, show little change in their moral development. Possibly, this relates to perceived pressures to conform to the informal culture of the medical wards. Many students experience considerable internal dissidence as they struggle to accommodate personal values related to ...


Toward An Ecosystem Approach To Remediation In The Great Basin, Ted K. Raab Jan 2000

Toward An Ecosystem Approach To Remediation In The Great Basin, Ted K. Raab

Ted K. Raab

We consider the web of interactions among geologic materials, soils, plants, and animals to ask, "If mining or other extractive energy technologies occur in desert regions, what do we need to know to return the land to productivity?" The Great Basin represents a formidable challenge in this regard, as winters in these cold deserts and seasonal lack of moisture during parts of the year severely constrain the growing season for vegetation. Due to the nature of current or proposed mining activities in this region, we have chosen to concentrate on two potential pollutants: the trace element selenium (Se) and nitrate ...


Size Selectivity Of Crappie Angling, Leandro E. Miranda, Brian S. Dorr Jan 2000

Size Selectivity Of Crappie Angling, Leandro E. Miranda, Brian S. Dorr

Brian S Dorr

Abstract.—Over 6,000 black crappies Pomoxis nigromaculatus and white crappies P. annularis were tagged in five lakes and reservoirs to quantify size selectivity of angling. Total length of fish tagged ranged from 20.0 to 39.8 cm; fish caught by anglers ranged from 20.0 to 38.8 cm. Return rates were low at lengths near 20 cm, increased gradually to a peak between 26 and 32 cm, and decreased for longer fish. This pattern was consistent among the five lakes and reservoirs and did not differ between species. Observed size-selective exploitation resulted in the lopsided removal of ...