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Articles 601 - 630 of 745

Full-Text Articles in Biology

Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam May 2004

Individual Cell Growth Rates Of Marine Bacteria, Measured By Bromodeoxyuridine Incorporation, Koji Hamasaki, Richard A. Long, Farooq Azam

Faculty Publications

We tested the application of 5-bromo-2’-deoxyuridine (BrdU), a thymidine analogue that becomes incorporated into DNA during growth, to measure growth rates of individual marine bacteria cells. Immunocytochemical detection of BrdU incorporation into bacterial DNA has the potential for single-cell-based growth measurement. Optimized procedure for immunocytochemistry was applicable to 14 marine heterotrophic bacterial isolates belonging to g-proteobacteria, α-proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group and Gram-positive bacteria. The relationship between cell-specific fluorescence intensity and specific growth rate was linearly correlated among CFB group isolates, which indicated a potential of the method for quantitative measurement. Analysis of the detection limit indicated …

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Dynamics Of Pectoral Fin Rowing In A Fish With An Extreme Rowing Stroke: The Threespine Stickleback (Gasterosteus Aculeatus), Jeffrey A. Walker Phd May 2004

Dynamics Of Pectoral Fin Rowing In A Fish With An Extreme Rowing Stroke: The Threespine Stickleback (Gasterosteus Aculeatus), Jeffrey A. Walker Phd

Faculty Publications

The dynamics of pectoral fin rowing in the threespine stickleback are investigated by measuring the instantaneous force balance on freely swimming fish throughout the stroke cycle and comparing the measured forces with fin motions and an unsteady, blade-element model of pectoral fin propulsion. Both measured and modeled forces suggest that attached vortex and circulatory forces and not inertial (added mass) forces dominate the force balance. Peak forces occur at midstrokes. There is no evidence for large force peaks at the stroke transitions due to either rapid fin rotation (supination) or rapid fin closure against the body. The energetics of pectoral …

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Particle Removal Rates By The Mud Shrimp Upogebia Pugettensis, Its Burrow, And A Commensal Clam: Effects On Estuarine Phytoplankton Abundance, Blaine D. Griffen, Theodore H. Dewitt, Chris Langdon Mar 2004

Particle Removal Rates By The Mud Shrimp Upogebia Pugettensis, Its Burrow, And A Commensal Clam: Effects On Estuarine Phytoplankton Abundance, Blaine D. Griffen, Theodore H. Dewitt, Chris Langdon

Faculty Publications

The burrowing shrimp Upogebia pugettensis is an abundant intertidal invertebrate of Pacific Northwest, USA bays and estuaries where it lives commensally with the bivalve Cryptomya californica. Suspension-feeding activities by the shrimp and by its commensal clam, as well as particle settlement within the burrow, represent 3 different components that could remove phytoplankton from water drawn into shrimp burrows. These 3 components together comprise what we call the ‘U. pugettensis shrimp-burrow complex’. In laboratory experiments, we measured particle removal by each of these components. Our results indicated that U. pugettensis itself is responsible for filtering the majority of phytoplankton removed …

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Seasonal Use Of Bridges By Rafinesque's Big-Eared Bat, Corynorhinus Rafinesquii, In Southern Mississippi, Austin W. Trousdale, David C. Beckett Mar 2004

Seasonal Use Of Bridges By Rafinesque's Big-Eared Bat, Corynorhinus Rafinesquii, In Southern Mississippi, Austin W. Trousdale, David C. Beckett

Faculty Publications

We conducted surveys of concrete bridges in southern Mississippi from 2000–2002 to determine the phenological pattern of use by Rafinesque's big-eared bat, Corynorhinus rafinesquii. The earliest dates on which we located maternity colonies were 9 March 2000, 20 April 2001, and 15 May 2002. Maternity colonies increased in size and abundance as spring progressed. Pups were born in mid- to late May (first observed 12 May 2000, 15 May 2001, 27 May 2002) and nursed through midsummer (lactating females last captured 14 July 2000, 25 July 2001, 16 July 2002). Colony size and percentage of bridges occupied by bats declined …

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The Agathidinae (Insecta: Hymenoptera: Braconidae) Of Sakhalin And The Kuril Islands, Michael J. Sharkey, Daniel J. Bennett Jan 2004

The Agathidinae (Insecta: Hymenoptera: Braconidae) Of Sakhalin And The Kuril Islands, Michael J. Sharkey, Daniel J. Bennett

Faculty Publications

Recent collecting on Sakhalin and the Kuril Islands, during joint U.S., Russian, and Japanese surveys known as the International Kuril and Sakhalin Island Projects, has resulted in range extensions for 10 species in the braconid subfamily Agathidinae and 17 new taxon records for islands in the Kuril chain, Sakhalin, and Moneron. In addition to a check list of the 19 species of Agathidinae presently known to occur on Sakhalin and the Kuril Islands, a generic key and updated keys to the species of Agathis Latreille, 1804, Bassus Fabricius, 1804, and Coccygidium Saussure, 1892 are provided for the region at large …

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Euglandina Rosea (Férussac, 1821) Is Found On The Ground And In Trees In Florida, Elizabeth C. Davis, Kathryn E. Perez, Daniel J. Bennett Jan 2004

Euglandina Rosea (Férussac, 1821) Is Found On The Ground And In Trees In Florida, Elizabeth C. Davis, Kathryn E. Perez, Daniel J. Bennett

Faculty Publications

Euglandina rosea (Ferussac, 1821) is a carnivorous snail native to the southeastern United States, including Florida (Hubricht, 1985; Wolfe and Brooks, 1968). It is known as a ground-dwelling terrestrial snail that feeds on terrestrial gastropods (Burch, 1962; Pilsbry, 1946). Introduced to Hawaii in 1955, it is one of the worst cases of an intended biological control agent attacking non-target species (Cowie, 2001). Exclosures keep it away from consuming remaining endemic snails, including the endangered Achatinella species (Stone, 1999).

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Snake (Colubridae: Thamnophis) Predatory Responses To Chemical Cues From Native And Introduced Prey Species, Stephen J. Mullin, Hélène Imbert, Jennifer M. Fish, Edward L. Ervin, Robert N. Fisher Jan 2004

Snake (Colubridae: Thamnophis) Predatory Responses To Chemical Cues From Native And Introduced Prey Species, Stephen J. Mullin, Hélène Imbert, Jennifer M. Fish, Edward L. Ervin, Robert N. Fisher

Faculty Publications

Several aquatic vertebrates have been introduced into freshwater systems in California over the past 100 years. Some populations of the two-striped garter snake (Thamnophis hammondii) have lived in sympatry with these species since their introduction; other populations have never encountered them. To assess the possible adaptation to a novel prey, we tested the predatory responses of T. hammondii from different populations to different chemosensory cues from native and introduced prey species. We presented chemical extracts from potential prey types and 2 control odors to individual snakes on cotton swabs and recorded the number of tongue flicks and attacks …

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Radio Telemetry And Post-Emergent Habitat Selection Of Neonate Box Turtles (Emydidae: Terrapene Carolina) In Central Illinois, Patrick Forsythe, Beth A. Flitz, Stephen J. Mullin Jan 2004

Radio Telemetry And Post-Emergent Habitat Selection Of Neonate Box Turtles (Emydidae: Terrapene Carolina) In Central Illinois, Patrick Forsythe, Beth A. Flitz, Stephen J. Mullin

Faculty Publications

Although factors influencing turtle offspring prior to nest emergence have received considerable attention by researchers (Gutzke and Crews 1988; Janzen et al. 2000; Packard and Packard 1987), the activity of neonates following their emergence from the nest is poorly understood (but see Burger 1976; Butler and Graham 1995; Keller et al. 1997). Previous field research has produced valuable information on several aspects of neonate ecology for several species (Brewster and Brewster 1991; Butler and Sowell 1996; Janzen 1993). However, a thorough understanding of life history patterns for many species is absent, and some existing information is conflicting (e.g., Congdon et …

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Influence Of Habitat And Number Of Nestlings On Partial Brood Loss In Red-Cockaded Woodpeckers, James R. Mccormick, Richard N. Conner, D. Brent Burt, Daniel Saenz Jan 2004

Influence Of Habitat And Number Of Nestlings On Partial Brood Loss In Red-Cockaded Woodpeckers, James R. Mccormick, Richard N. Conner, D. Brent Burt, Daniel Saenz

Faculty Publications

Partial brood loss in red-cockaded woodpeckers (Picoides borealis) was studied during 2 breeding seasons in eastern Texas. The timing of partial brood loss, group size, number of initial nestlings, number of birds fledged, and habitat characteristics of the group's cavity-tree cluster were examined for 37 woodpecker groups in loblolly- (Pinus taeda) shortleaf (P. echinata) pine habitat and 14 groups in longleaf (P palustris) pine habitat. Partial brood loss occurred slightly more in the loblolly-shortleaf pine habitat than in the longleaf pine habitat, largely because nests in loblolly-shortleaf habitat initially contained more nestlings. …

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Evidence Of Red-Cockaded Woodpecker Nestling Displacement By Southern Flying Squirrels., Brent Burt, James R. Mccormick, Richard N. Conner, Daniel Saenz Jan 2004

Evidence Of Red-Cockaded Woodpecker Nestling Displacement By Southern Flying Squirrels., Brent Burt, James R. Mccormick, Richard N. Conner, Daniel Saenz

Faculty Publications

Red-cockaded Woodpeckers are unique among woodpeckers in that they excavate their roost and nest cavities entirely within living pines. Studies show that there is a propensity for squirrels to use unenlarged cavities, none have shown evidence of Red-cockaded Woodpeckers being killed by southern flying squirrels. However, we report an instance of two nestlings found dead at the base of the nest tree and 3 flying squirrels inside the nest cavity.

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Relationships Between Habitat And Snag Characteristics And The Reproductive Success Of The Brown-Headed Nuthatch (Sitta Pusilla) In Eastern Texas., L. Lynnette Dornak, Brent Burt, Dean W. Coble, Richard N. Conner Jan 2004

Relationships Between Habitat And Snag Characteristics And The Reproductive Success Of The Brown-Headed Nuthatch (Sitta Pusilla) In Eastern Texas., L. Lynnette Dornak, Brent Burt, Dean W. Coble, Richard N. Conner

Faculty Publications

Habitat use and reproductive success of the Brown-headed Nuthatch (Sitta pusilla Latham) were studied in East Texas during the 2001-2002 breeding seasons. We compared nest cavity selection at used and randomly selected non-used areas. Height of nest trees, midstory density, and percent leaf litter were negatively correlated with nest site selection. Brown-headed Nuthatches showed a strong preference for short snags; yet placed their nest cavity entrances near the top ofthe snags. While nuthatches may be selecting for habitats with little or no midstory density, percent of leaf litter in the nest sites is most likely the consequence of frequent burning. …

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Sterol Carrier Protein-2 Directly Interacts With Caveolin-1 In Vitro And In Vivo, Minglong Zhou, Rebecca D. Parr, Anca D. Petrescu, H. Ross Payne, Barbara P. Atshaves, Ann B. Kier, Judith M. Ball, Friedhelm Schroeder Jan 2004

Sterol Carrier Protein-2 Directly Interacts With Caveolin-1 In Vitro And In Vivo, Minglong Zhou, Rebecca D. Parr, Anca D. Petrescu, H. Ross Payne, Barbara P. Atshaves, Ann B. Kier, Judith M. Ball, Friedhelm Schroeder

Faculty Publications

HDL-mediated reverse-cholesterol transport as well as phosphoinositide signaling are mediated through plasma membrane microdomains termed caveolae/lipid rafts. However, relatively little is known regarding mechanism(s) whereby these lipids traffic to or are targeted to caveolae/lipid rafts. Since sterol carrier protein-2 (SCP-2) binds both cholesterol and phosphatidylinositol, the possibility that SCP-2 might interact with caveolin-1 and caveolae was examined. Double immunolabeling and laser scanning fluorescence microscopy showed that a small but significant portion of SCP-2 colocalized with caveolin-1 primarily at the plasma membrane of L-cells and more so within intracellular punctuate structures in hepatoma cells. In SCP-2 overexpressing L-cells, SCP-2 was detected …

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Survey Of Salamanders In Mississippi Limestone Caves, John G. Himes, David C. Beckett, Austin W. Trousdale Jan 2004

Survey Of Salamanders In Mississippi Limestone Caves, John G. Himes, David C. Beckett, Austin W. Trousdale

Faculty Publications

During 2000-2002 we surveyed for salamanders in the larger limestone caves of Mississippi, all within the Vicksburg Group rock unit. We found four species: Plethodon mississippi was the most abundant, followed by Eurycea guttolineata, Eurycea cirrigera, and Desmognathus conanti. We did not find Pseudotriton montanus in any of the caves, and question the validity of an investigator's statement made nearly 45 years ago that, "it is one of the most numerous salamanders in Mississippi. limestone caves." The salamander fauna we found is similar to that of the only other comprehensive survey of salamanders in Mississippi caves, conducted almost thirty years …

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Long-Lived Worms And Aging, Yuan Luo Jan 2004

Long-Lived Worms And Aging, Yuan Luo

Faculty Publications

Several investigators have generated long-lived nematode worms (Caenorhabditis elegans) in the past decade by mutation of genes in the organism in order to study the genetics of aging and longevity. Dozens of longevity assurance genes (LAG) that dramatically increase the longevity of this organism have been identified. All long-lived mutants of C. elegans are also resistant to environmental stress, such as high temperature, reactive oxygen species (ROS), and ultraviolet irradiation. Double mutations of some LAGS further extended life span up to 400%, providing more insight into cellular mechanisms that put limits on the life span of organisms. With …

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Multiple Domains Of The Co-Chaperone Hop Are Important For Hsp70 Binding, Gregory M. Nelson, Patricia E. Carrigan, Patricia J. Roberts, Jha'nae Stoffer, Daniel L. Riggs, David F. Smith Jan 2004

Multiple Domains Of The Co-Chaperone Hop Are Important For Hsp70 Binding, Gregory M. Nelson, Patricia E. Carrigan, Patricia J. Roberts, Jha'nae Stoffer, Daniel L. Riggs, David F. Smith

Faculty Publications

The Hop/Sti1 co-chaperone binds to both Hsp70 and Hsp90. Biochemical and co-crystallographic studies have suggested that the EEVD-containing C terminus of Hsp70 or Hsp90 binds specifically to one of the Hop tetratricopeptide repeat domains, TPR1 or TPR2a, respectively. Mutational analyses of Hsp70 and Hop were undertaken to better characterize interactions between the C terminus of Hsp70 and Hop domains. Surprisingly, truncation of EEVD plus as many as 34 additional amino acids from the Hsp70 C terminus did not reduce the ability of Hsp70 mutants to co-immunoprecipitate with Hop, although further truncation eliminated Hop binding. Hop point mutations targeting a carboxylate …

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Effect Of Diet On Bullfrog (Rana Catesbeiana) Tadpole Growth And Development, A. H. Michajliczenko, Geoffrey R. Smith, Jessica E. Rettig Jan 2004

Effect Of Diet On Bullfrog (Rana Catesbeiana) Tadpole Growth And Development, A. H. Michajliczenko, Geoffrey R. Smith, Jessica E. Rettig

Faculty Publications

No abstract provided.

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Summer Activity Of Small Snakes In Four Habitats In Northwestern Missouri, L. D. Johnson, Geoffrey R. Smith, Jessica E. Rettig Jan 2004

Summer Activity Of Small Snakes In Four Habitats In Northwestern Missouri, L. D. Johnson, Geoffrey R. Smith, Jessica E. Rettig

Faculty Publications

No abstract provided.

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Threatened Fishes Of The World: Iotichthys Phlegethontis Cope, 1874 (Cyprinidae), Joseph H. Hanks, Mark C. Belk Jan 2004

Threatened Fishes Of The World: Iotichthys Phlegethontis Cope, 1874 (Cyprinidae), Joseph H. Hanks, Mark C. Belk

Faculty Publications

Common name: least chub.

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Nitric Oxide Mediates Seasonal Muscle Potentiation In Clam Gills, Louis F. Gainey Jr., Michael J. Greenberg Oct 2003

Nitric Oxide Mediates Seasonal Muscle Potentiation In Clam Gills, Louis F. Gainey Jr., Michael J. Greenberg

Faculty Publications

The physiology and timing of gill muscle potentiation were explored in the clam Mercenaria mercenaria. When isolated demibranchs were exposed twice (with an intervening wash) to the same concentration of 5-hydroxytryptamine, the second contraction was larger than the first. This potentiation was seasonal: it was present from November through June, and absent from July through October. Potentiation was not affected by the geographic origin of the clams, nor by their acclimation temperature. Potentiation was inhibited by the nitric oxide synthase (NOS) inhibitor L-NAME and mimicked by the nitric oxide (NO) donor DEANO. During the season of potentiation, immunoreactive NOS appeared …

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P-Limitation Of Respiration In The Sargasso Sea And Uncoupling Of Bacteria From P-Regeneration In Size-Fractionation Experiments, Ingrid Obernosterer, Nobu Kawasaki, Ronald Benner Jul 2003

P-Limitation Of Respiration In The Sargasso Sea And Uncoupling Of Bacteria From P-Regeneration In Size-Fractionation Experiments, Ingrid Obernosterer, Nobu Kawasaki, Ronald Benner

Faculty Publications

Community respiration rates were measured in unfiltered seawater collected in the upper 75 m of the water column along a transect in the Sargasso Sea and at the Bermuda Atlantic Time-series Study (BATS) station (31° 50’ 00 N; 64° 10’ 00 W) during a cruise in June and July 2001. Community respiration rates in the upper 75 m of the water column averaged 1.1 ± 0.4 μM O2 d-1 and exhibited significant spatial and temporal variability. Concurrent determination of the heterotrophic and autotrophic community revealed no relationship between community respiration and the abundance of any of the major …

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Evidence For Survival Of Pleistocene Climatic Changes In Northern Refugia By The Land Snail Trochoidea Geyeri, David Posada, Markus Pfenninger, Frederic Magnin Apr 2003

Evidence For Survival Of Pleistocene Climatic Changes In Northern Refugia By The Land Snail Trochoidea Geyeri, David Posada, Markus Pfenninger, Frederic Magnin

Faculty Publications

The study of organisms with restricted dispersal abilities and presence in the fossil record is particularly adequate to understand the impact of climate changes on the distribution and genetic structure of species. Trochoidea geyeri (Soos 1926) is a land snail restricted to a patchy, insular distribution in Germany and France. Fossil evidence suggests that current populations of T. geyeri are relicts of a much more widespread distribution during more favourable climatic periods in the Pleistocene. Results: Phylogeographic analysis of the mitochondrial 16S rDNA and nuclear ITS-1 sequence variation was used to infer the history of the remnant populations of T. …

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Aintegumenta Utilizes A Mode Of Dna Recognition Distinct From That Used By Proteins Containing A Single Ap2 Domain, Beth A. Krizek Apr 2003

Aintegumenta Utilizes A Mode Of Dna Recognition Distinct From That Used By Proteins Containing A Single Ap2 Domain, Beth A. Krizek

Faculty Publications

The Arabidopsis protein AINTEGUMENTA (ANT) is an important regulator of organ growth during flower development. ANT is a member of the AP2 subclass of the AP2/ERF family of plant-specific transcription factors. These proteins contain either one or two copies of a DNA-binding domain called the AP2 domain. Here, it is shown that ANT can act as a transcriptional activator in yeast through binding to a consensus ANT-binding site. This activity was used as the basis for a genetic screen to identify amino acids that are critical for the DNA binding ability of ANT. Mutants that showed reduced or no activation …

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Biochemical Composition Of Embryonic Blue Crabs Callinectes Sapidus Rathbun 1896 (Crustacea : Decapoda) From The Gulf Of Mexico, Janet R. Jacobs, Patricia M. Biesiot, Harriet M. Perry, Christine Trigg Mar 2003

Biochemical Composition Of Embryonic Blue Crabs Callinectes Sapidus Rathbun 1896 (Crustacea : Decapoda) From The Gulf Of Mexico, Janet R. Jacobs, Patricia M. Biesiot, Harriet M. Perry, Christine Trigg

Faculty Publications

Blue crab Callinectes sapidus embryos from the Mississippi Sound were sampled in spring and in late summer to determine patterns of biochemical composition and of yolk utilization during embryogenesis and to ascertain potential seasonal differences in biochemical composition. The diameter of spring embryos was similar to 6% greater than summer embryos but this significant size difference was due to increased water content, not to increased organic content. The general trend in initial biochemical composition was similar in both seasons; protein was the primary component at similar to 50% of initial dry weight followed by lipid (similar to 30%), ash (similar …

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Microalgal-Meiofaunal Trophic Relationships In Muddy Intertidal Estuarine Sediments, James L. Pinckney, Kevin R. Carman, S. Elizabeth Lumsden, Sabrina N. Hymel Feb 2003

Microalgal-Meiofaunal Trophic Relationships In Muddy Intertidal Estuarine Sediments, James L. Pinckney, Kevin R. Carman, S. Elizabeth Lumsden, Sabrina N. Hymel

Faculty Publications

The determination of the primary factors controlling carbon (C) transfer rates in situ are a basic requirement for developing a mechanistic view of the processes that regulate benthic microbial community structure and function. In many estuarine ecosystems, the base of the food web is dominated by microalgal production; however, information on the quantitative relationships and process rates of meiofaunal grazers and benthic microalgal (BMA) producers is limited to a few habitats and short temporal scales. The primary objective of this study was to examine the trophic interactions between meiofaunal grazers and BMA producers to determine if grazing is a primary …

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Biodiversity And Biogeography Of The Islands Of The Kuril Archipelago [Abstract], Theodore W. Pietsch, Victor V. Bogatov, Kunio Amaoka, Yuri N. Zhuravlev, Vyacheslav Y. Barkalov, Sarah Gage, Hideki Takahashi, Arkady S. Lelej, Sergey Y. Storozhenko, Noboru Minakawa, Daniel J. Bennett, Trevor R. Anderson, Masahiro Ôhara, Larisa A. Prozorova, Yasuhiro Kuwahara, Sergey K. Kholin, Mamoru Yabe, Duane E. Stevenson, Erin L. Macdonald Jan 2003

Biodiversity And Biogeography Of The Islands Of The Kuril Archipelago [Abstract], Theodore W. Pietsch, Victor V. Bogatov, Kunio Amaoka, Yuri N. Zhuravlev, Vyacheslav Y. Barkalov, Sarah Gage, Hideki Takahashi, Arkady S. Lelej, Sergey Y. Storozhenko, Noboru Minakawa, Daniel J. Bennett, Trevor R. Anderson, Masahiro Ôhara, Larisa A. Prozorova, Yasuhiro Kuwahara, Sergey K. Kholin, Mamoru Yabe, Duane E. Stevenson, Erin L. Macdonald

Faculty Publications

No abstract provided.

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To The Knowledge Of Trigonalyid Wasps (Hymenoptera: Trigonalyidae) Of Sakhalin, Daniel J. Bennett, Arkady S. Lelej Jan 2003

To The Knowledge Of Trigonalyid Wasps (Hymenoptera: Trigonalyidae) Of Sakhalin, Daniel J. Bennett, Arkady S. Lelej

Faculty Publications

The northern border for the distribution of the Trigonalyidae on Sakhalin is moved northwards to 49° N. The genus Orthogonalys Schulz, 1905 and O. elongata (Teranishi, 1929) are new for Sakhalin fauna.

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Blackspot Disease Of Roses [Abstract], Robert J. Wiggers, Josephine Taylor, J. A. Margoitta, S. G. Pandalai Jan 2003

Blackspot Disease Of Roses [Abstract], Robert J. Wiggers, Josephine Taylor, J. A. Margoitta, S. G. Pandalai

Faculty Publications

No abstract provided.

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Accelerated Hatching Of Southern Leopard Frog (Rana Sphenocephala) Eggs In Response To The Presence Of A Crayfish (Procambarus Nigrocinctus) Predator, Daniel Saenz, James B. Johnson, Cory K. Adams, Gage H. Dayton Jan 2003

Accelerated Hatching Of Southern Leopard Frog (Rana Sphenocephala) Eggs In Response To The Presence Of A Crayfish (Procambarus Nigrocinctus) Predator, Daniel Saenz, James B. Johnson, Cory K. Adams, Gage H. Dayton

Faculty Publications

Phenotypic plasticity, such as morphological and behavioral changes in response to predators, is common in larval anurans. Less is known about inducible defenses in the embryonic stages of development. We investigated the predation risk imposed by crayfish (Procambarus nigrocinctus) on southern leopard frog (Rana sphenocephala) eggs aud whether crayfish presence induces a change in the timing of hatching of R. sphenocephala eggs. We found that crayfish significantly reduce the hatching success of R. sphenocephala eggs by eating them and that eggs hatch significantly faster in the presence of crayfish than when crayfish are not present. We …

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The Influence Of Predator Threat On The Timing Of A Life-History Switch Point: Predator-Induced Hatching In The Southern Leopard Frog (Rana Sphenocephala), James B. Johnson, Daniel Saenz, Cory K. Adams, Richard N. Conner Jan 2003

The Influence Of Predator Threat On The Timing Of A Life-History Switch Point: Predator-Induced Hatching In The Southern Leopard Frog (Rana Sphenocephala), James B. Johnson, Daniel Saenz, Cory K. Adams, Richard N. Conner

Faculty Publications

We tested the hypotheses that potential egg predators, crayfish Procambarus nigrocinctus and dytiscid Cybister sp. larvae, would accelerate the timing of hatching and that a larval predator, dragonfly naiad Anax junius, would delay hatching in the southern leopard frog (Rana sphenocephala). We also tested the hypothesis that differences in response would be proportional to predator lethality. Our results indicate that our hypotheses were partially supported. The presence of an efficient egg predator (crayfish) induces hatching faster than a less efficient predator (dytiscid larvae). However, the presence of a larval predator (naiads) did not delay hatching. Eggs that …

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Site‐Selective In Vivo Targeting Of Cytosine‐5 Dna Methylation By Zinc‐Finger Proteins, Christopher D. Carvin, Rebecca D. Parr, Michael P. Kladde Jan 2003

Site‐Selective In Vivo Targeting Of Cytosine‐5 Dna Methylation By Zinc‐Finger Proteins, Christopher D. Carvin, Rebecca D. Parr, Michael P. Kladde

Faculty Publications

Cytosine‐5 DNA methylation is a critical signal defining heritable epigenetic states of transcription. As aberrant methylation patterns often accompany disease states, the ability to target cytosine methylation to preselected regions could prove valuable in re‐establishing proper gene regulation. We employ the strategy of targeted gene methylation in yeast, which has a naturally unmethylated genome, selectively directing de novo DNA methylation via the fusion of C5 DNA methyltransferases to heterologous DNA‐binding proteins. The zinc‐finger proteins Zif268 and Zip53 can target DNA methylation by M.CviPI or M.SssI 5–52 nt from single zinc‐factor binding sites. Modification at specific GC (M.CviPI) or CG (M.SssI) …

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