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• 981. [Article] Development of a singulation device for stonefly larva

  Population counts of aquatic insects can be a credible indicator of the overall health of a waterway. Stonefly (Plecoptera) larva are very sensitive to chemicals present within the waterway, however obtaining ...

  Citation × Citation Citation Abstract Copy Title: Development of a singulation device for stonefly larva Author: Williams, Kate S. (Kate Shreeve) Population counts of aquatic insects can be a credible indicator of the overall health of a waterway. Stonefly (Plecoptera) larva are very sensitive to chemicals present within the waterway, however obtaining population counts of the larvae can be very labor intensive and thus costly. The BugID project has been working to create an automated system to classify the different species of stonefly larva. The current imaging devices require extensive time from a lab technician to individually place stonefly larva into the device. This paper describes the development of a singulation device which would individually remove stonefly larva from a field sample and place them into the imaging device, resulting in a possible solution to help automate the identification process of the larva. Title: Development of a singulation device for stonefly larva Author: Williams, Kate S. (Kate Shreeve) Population counts of aquatic insects can be a credible indicator of the overall health of a waterway. Stonefly (Plecoptera) larva are very sensitive to chemicals present within the waterway, however obtaining population counts of the larvae can be very labor intensive and thus costly. The BugID project has been working to create an automated system to classify the different species of stonefly larva. The current imaging devices require extensive time from a lab technician to individually place stonefly larva into the device. This paper describes the development of a singulation device which would individually remove stonefly larva from a field sample and place them into the imaging device, resulting in a possible solution to help automate the identification process of the larva. Close

• 982. [Article] Exploring the phylogenetic affiliations and the trophic mode of Sedecula pulvinata (Sedeculaceae)

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Mycological Society of America and can be found at: http://www.mycologia.or...

  Citation × Citation Citation Abstract Copy Title: Exploring the phylogenetic affiliations and the trophic mode of Sedecula pulvinata (Sedeculaceae) Author: Smith, Matthew E., Trappe, Matthew J., Hobbie, Erik A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Mycological Society of America and can be found at: http://www.mycologia.org/ Title: Exploring the phylogenetic affiliations and the trophic mode of Sedecula pulvinata (Sedeculaceae) Author: Smith, Matthew E., Trappe, Matthew J., Hobbie, Erik A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Mycological Society of America and can be found at: http://www.mycologia.org/ Close

• 983. [Article] Improved stability of amorphous zinc tin oxide thin film transistors using molecular passivation

  This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Physics Publishing and can be found at: http://scitation.aip.org/content/aip/journal/apl.

  Citation × Citation Citation Abstract Copy Title: Improved stability of amorphous zinc tin oxide thin film transistors using molecular passivation Author: Herman, G. S., Pandey, A., Vilayurganapathy, S., Nachimuthu, P., Thevuthasan, S., Rajachidambaram, M. S. This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Physics Publishing and can be found at: http://scitation.aip.org/content/aip/journal/apl. Title: Improved stability of amorphous zinc tin oxide thin film transistors using molecular passivation Author: Herman, G. S., Pandey, A., Vilayurganapathy, S., Nachimuthu, P., Thevuthasan, S., Rajachidambaram, M. S. This is the publisher’s final pdf. The published article is copyrighted by the American Institute of Physics Publishing and can be found at: http://scitation.aip.org/content/aip/journal/apl. Close

• 984. [Article] A Vector–Host Model for Coinfection by Barley/Cereal Yellow Dwarf Viruses

  Barley and cereal yellow dwarf viruses (B/CYDV) are a suite of aphid-vectored pathogens that affect diverse host communities, including economically important crops. Coinfection of a single host by multiple ...

  Citation × Citation Citation Abstract Copy Title: A Vector–Host Model for Coinfection by Barley/Cereal Yellow Dwarf Viruses Author: Leung, Margaret-Rose W. Barley and cereal yellow dwarf viruses (B/CYDV) are a suite of aphid-vectored pathogens that affect diverse host communities, including economically important crops. Coinfection of a single host by multiple strains of B/CYDV can result in elevated virulence, incidence, and transmission rates. We develop a model for a single host, two pathogen strains, and n vector species, modeled by a system of nonlinear ordinary differential equations. A single parameter describes the degree of relatedness of the strains and the amount of cross-protection between them. We compute the basic and type reproduction numbers for the model and analytically prove the (conditional) stability of the disease-free equilibrium. We demonstrate numerically that, although the basic reproduction number describes stability of the disease-free equilibrium, the type reproduction numbers better describe the individual behavior of each strain and the dynamics of coinfection. We then conduct a sensitivity analysis on the components of the endemic equilibrium for two different vector growth functions. Our results indicate that the disease transmission rates and the vector birth and mortality rates are the most influential parameters for the equilibrium prevalences of infection and coinfection. Title: A Vector–Host Model for Coinfection by Barley/Cereal Yellow Dwarf Viruses Author: Leung, Margaret-Rose W. Barley and cereal yellow dwarf viruses (B/CYDV) are a suite of aphid-vectored pathogens that affect diverse host communities, including economically important crops. Coinfection of a single host by multiple strains of B/CYDV can result in elevated virulence, incidence, and transmission rates. We develop a model for a single host, two pathogen strains, and n vector species, modeled by a system of nonlinear ordinary differential equations. A single parameter describes the degree of relatedness of the strains and the amount of cross-protection between them. We compute the basic and type reproduction numbers for the model and analytically prove the (conditional) stability of the disease-free equilibrium. We demonstrate numerically that, although the basic reproduction number describes stability of the disease-free equilibrium, the type reproduction numbers better describe the individual behavior of each strain and the dynamics of coinfection. We then conduct a sensitivity analysis on the components of the endemic equilibrium for two different vector growth functions. Our results indicate that the disease transmission rates and the vector birth and mortality rates are the most influential parameters for the equilibrium prevalences of infection and coinfection. Close

• 985. [Article] Characterization of the Plasmids of the Pathogenic Plant Bacterium Erwinia amylovora in Washington and Oregon

  Erwinia amylovora is a plant pathogenic bacterium that causes the destructive disease fire blight of apple and pear. We examined the plasmid content of a collection of 305 isolates of E. amylovora from ...

  Citation × Citation Citation Abstract Copy Title: Characterization of the Plasmids of the Pathogenic Plant Bacterium Erwinia amylovora in Washington and Oregon Author: Carey, Alyssa B. Erwinia amylovora is a plant pathogenic bacterium that causes the destructive disease fire blight of apple and pear. We examined the plasmid content of a collection of 305 isolates of E. amylovora from Washington and Oregon with PCR assays and RFLP. Nearly all isolates of E. amylovora carried plasmid pEA29, which is not found in other species of bacteria, but 4% of the isolates from this region lacked pEA29. The plasmid pEU30, previously reported in pathogen strains from western states in the USA, was detected in 28% of isolates. The RFLP patterns of plasmid preparations from a third of isolates from an epidemic in Washington in 1988 had altered RFLP patterns, possibly due to the presence of plasmid(s) in addition to pEA29 or pEU30. Considering all samples, the majority of isolates in this region was typical of E. amylovora and harbored only pEA29. Nonetheless, many of the pathogen isolates had altered plasmid content, indicating that plasmid acquisition and propagation in populations of E. amylovora in orchards in the Northwestern USA is more common than previously assumed. Title: Characterization of the Plasmids of the Pathogenic Plant Bacterium Erwinia amylovora in Washington and Oregon Author: Carey, Alyssa B. Erwinia amylovora is a plant pathogenic bacterium that causes the destructive disease fire blight of apple and pear. We examined the plasmid content of a collection of 305 isolates of E. amylovora from Washington and Oregon with PCR assays and RFLP. Nearly all isolates of E. amylovora carried plasmid pEA29, which is not found in other species of bacteria, but 4% of the isolates from this region lacked pEA29. The plasmid pEU30, previously reported in pathogen strains from western states in the USA, was detected in 28% of isolates. The RFLP patterns of plasmid preparations from a third of isolates from an epidemic in Washington in 1988 had altered RFLP patterns, possibly due to the presence of plasmid(s) in addition to pEA29 or pEU30. Considering all samples, the majority of isolates in this region was typical of E. amylovora and harbored only pEA29. Nonetheless, many of the pathogen isolates had altered plasmid content, indicating that plasmid acquisition and propagation in populations of E. amylovora in orchards in the Northwestern USA is more common than previously assumed. Close

• 986. [Article] Exploring the phylogenetic affiliations and the trophic mode of Sedecula pulvinata (Sedeculaceae)

  This is the publisher’s final pdf. The published article is copyrighted by Mycological Society of America and can be found at: http://msafungi.org/mycologia/

  Citation × Citation Citation Abstract Copy Title: Exploring the phylogenetic affiliations and the trophic mode of Sedecula pulvinata (Sedeculaceae) Author: Smith, Matthew E., Trappe, Matthew J., Hobbie, Erik A. This is the publisher’s final pdf. The published article is copyrighted by Mycological Society of America and can be found at: http://msafungi.org/mycologia/ Title: Exploring the phylogenetic affiliations and the trophic mode of Sedecula pulvinata (Sedeculaceae) Author: Smith, Matthew E., Trappe, Matthew J., Hobbie, Erik A. This is the publisher’s final pdf. The published article is copyrighted by Mycological Society of America and can be found at: http://msafungi.org/mycologia/ Close

• 987. [Article] Play behavior in the golden hamster

  Intensive observations were made of play behavior in the young hamster (Mesocricetus auratus) from 14 to 54 days of age. Behavior was recorded using movie film and a multi-channel event recorder. Play ...

  Citation × Citation Citation Abstract Copy Title: Play behavior in the golden hamster Author: Kreitlow, Jean Louise Intensive observations were made of play behavior in the young hamster (Mesocricetus auratus) from 14 to 54 days of age. Behavior was recorded using movie film and a multi-channel event recorder. Play was first seen at 14 days of age. The amount of play increased rapidly thereafter, remaining relatively high until about day 40. Playing then decreased, becoming sporadic by day 54. This decline corresponded to an increase in agonistic encounters. Play bouts were generally shorter during the first days of play, and also shorter after day 40, as aggression increased. When play bout duration was plotted as a survivorship function, the result was significantly different from a straight line, indicating that the probability of a bout ending is not independent of how long it has lasted. Play bouts were relatively simple at first, becoming more complex as motor patterns were added during ontogeny. The sequence of motor patterns in playful interactions resembled the patterns later seen in agonistic encounters. The data are discussed with regard to some of the current theories of play. Play does not seem to function for exercise or the formation of positive social bonds. It is hypothesized that play in this species may be only the ontogeny of agonistic behavior. Title: Play behavior in the golden hamster Author: Kreitlow, Jean Louise Intensive observations were made of play behavior in the young hamster (Mesocricetus auratus) from 14 to 54 days of age. Behavior was recorded using movie film and a multi-channel event recorder. Play was first seen at 14 days of age. The amount of play increased rapidly thereafter, remaining relatively high until about day 40. Playing then decreased, becoming sporadic by day 54. This decline corresponded to an increase in agonistic encounters. Play bouts were generally shorter during the first days of play, and also shorter after day 40, as aggression increased. When play bout duration was plotted as a survivorship function, the result was significantly different from a straight line, indicating that the probability of a bout ending is not independent of how long it has lasted. Play bouts were relatively simple at first, becoming more complex as motor patterns were added during ontogeny. The sequence of motor patterns in playful interactions resembled the patterns later seen in agonistic encounters. The data are discussed with regard to some of the current theories of play. Play does not seem to function for exercise or the formation of positive social bonds. It is hypothesized that play in this species may be only the ontogeny of agonistic behavior. Close

• 988. [Article] Interactions and persistence of the mosquitocidal bacteria Bacillus sphaericus and Bacillus thuringiensis var. israelensis

  Interactions between Bacillus sphaericus and Bacillus thuringiensis israelensis (Bti), persistence of insecticidal activity in the mosquito habitat, and suitability of enzyme-linked immunoabsorbent assay ...

  Citation × Citation Citation Abstract Copy Title: Interactions and persistence of the mosquitocidal bacteria Bacillus sphaericus and Bacillus thuringiensis var. israelensis Author: Donegan, Katherine K. Interactions between Bacillus sphaericus and Bacillus thuringiensis israelensis (Bti), persistence of insecticidal activity in the mosquito habitat, and suitability of enzyme-linked immunoabsorbent assay (ELISA) for detecting and quantifying bacterial endotoxin in the mosquito habitat were investigated. Interactions between the two bacterial species were examined by laboratory and field bioassays with larvae of Culex pipiens. In laboratory bioassays, B. sphaericus and Bti acted independently. Antagonistic interactions occurred with combinations of a low concentration of one bacterium with a high concentration of the second, however. In field bioassays, all interactions between Bti and B. sphaericus were antagonistic. Field bioassays with C. pipiens indicated no persistence of insecticidal activity of either Bti or B. sphaericus after two treatments and persistence of only B. sphaericus after 3 and 4 treatments. Organic matter and high temperatures adversely affected the accuracy of ELISA for detecting and quantifying bacteria in the mosquito habitat and may play a major role in detoxification of bacterial endotoxin in nature. Title: Interactions and persistence of the mosquitocidal bacteria Bacillus sphaericus and Bacillus thuringiensis var. israelensis Author: Donegan, Katherine K. Interactions between Bacillus sphaericus and Bacillus thuringiensis israelensis (Bti), persistence of insecticidal activity in the mosquito habitat, and suitability of enzyme-linked immunoabsorbent assay (ELISA) for detecting and quantifying bacterial endotoxin in the mosquito habitat were investigated. Interactions between the two bacterial species were examined by laboratory and field bioassays with larvae of Culex pipiens. In laboratory bioassays, B. sphaericus and Bti acted independently. Antagonistic interactions occurred with combinations of a low concentration of one bacterium with a high concentration of the second, however. In field bioassays, all interactions between Bti and B. sphaericus were antagonistic. Field bioassays with C. pipiens indicated no persistence of insecticidal activity of either Bti or B. sphaericus after two treatments and persistence of only B. sphaericus after 3 and 4 treatments. Organic matter and high temperatures adversely affected the accuracy of ELISA for detecting and quantifying bacteria in the mosquito habitat and may play a major role in detoxification of bacterial endotoxin in nature. Close

• 989. [Article] Heat balance of alcoves on the Willamette River, Oregon.

  Alcoves in some river systems are cooler than the mainstem of the river and provide thermal refugia for aquatic species. An energy balance and sensitivity analysis on 3 alcoves in the Willamette River, ...

  Citation × Citation Citation Abstract Copy Title: Heat balance of alcoves on the Willamette River, Oregon. Author: Bryenton, Andrew G. Alcoves in some river systems are cooler than the mainstem of the river and provide thermal refugia for aquatic species. An energy balance and sensitivity analysis on 3 alcoves in the Willamette River, Oregon indicate that alcove size and alcove flux determine the degree to which meteorological conditions affect the alcove water temperature. Large alcoves with a low alcove flux and large surface area are more sensitive to meteorological conditions (i.e., shade and wind). Small alcoves with a high alcove flux and small surface area are more sensitive to the temperature of emerging subsurface water than to meteorological conditions. The temperature of hyporheic water relative to the mainstem is determined by its residence time; longer flow paths disperse the diurnal signal and move hyporheic water into equilibrium with mean seasonal or annual subsurface temperatures. Floodplain restoration may increase alcove population in a river system thereby making it a potential credit trading tool for mitigating excess thermal loading in a heat stressed river. Title: Heat balance of alcoves on the Willamette River, Oregon. Author: Bryenton, Andrew G. Alcoves in some river systems are cooler than the mainstem of the river and provide thermal refugia for aquatic species. An energy balance and sensitivity analysis on 3 alcoves in the Willamette River, Oregon indicate that alcove size and alcove flux determine the degree to which meteorological conditions affect the alcove water temperature. Large alcoves with a low alcove flux and large surface area are more sensitive to meteorological conditions (i.e., shade and wind). Small alcoves with a high alcove flux and small surface area are more sensitive to the temperature of emerging subsurface water than to meteorological conditions. The temperature of hyporheic water relative to the mainstem is determined by its residence time; longer flow paths disperse the diurnal signal and move hyporheic water into equilibrium with mean seasonal or annual subsurface temperatures. Floodplain restoration may increase alcove population in a river system thereby making it a potential credit trading tool for mitigating excess thermal loading in a heat stressed river. Close

• 990. [Article] Characterization of cytokinin metabolic enzymes from Phaseolus

  An enzyme catalyzing the formation of O-glucosylzeatin in immature embryos of P. lunatus was purified 2500 fold using ammonium sulfate precipitation followed by affinity and anion exchange chromatography. The ...

  Citation × Citation Citation Abstract Copy Title: Characterization of cytokinin metabolic enzymes from Phaseolus Author: Dixon, Susan C. An enzyme catalyzing the formation of O-glucosylzeatin in immature embryos of P. lunatus was purified 2500 fold using ammonium sulfate precipitation followed by affinity and anion exchange chromatography. The enzyme uses trans-zeatin as substrate (Km 28 uM) but not cis-zeatin. ribosylzeatin, or dihydrozeatin. Both UDP-glucose and UDP-xylose can serve as glycosyl donors, with Kms of 0.2 and 2.7 mM respectively, for the formation of O-glucosylzeatin and O-xylosylzeatin. In comparison, the UDPxylose:zeatin O-xylosyltransferase (Turner et al., 1987) isolated by the same procedures from P. vulgaris embryos uses only UDP-xylose as donor substrate and the Kms for both zeatin and UDP-xylose are much lower (2 and 3 micromolar, respectively). The chromatographic behavior on affinity columns and the molecular weights (approximate Mr 44,000 daltons) of the two enzymes are similar. Results from substrate competition experiments and enzyme separation by anion exchange HPLC indicate a single, distinct, zeatin O-glycosylation enzyme occurs in embryos of each of these Phaseolus species. Title: Characterization of cytokinin metabolic enzymes from Phaseolus Author: Dixon, Susan C. An enzyme catalyzing the formation of O-glucosylzeatin in immature embryos of P. lunatus was purified 2500 fold using ammonium sulfate precipitation followed by affinity and anion exchange chromatography. The enzyme uses trans-zeatin as substrate (Km 28 uM) but not cis-zeatin. ribosylzeatin, or dihydrozeatin. Both UDP-glucose and UDP-xylose can serve as glycosyl donors, with Kms of 0.2 and 2.7 mM respectively, for the formation of O-glucosylzeatin and O-xylosylzeatin. In comparison, the UDPxylose:zeatin O-xylosyltransferase (Turner et al., 1987) isolated by the same procedures from P. vulgaris embryos uses only UDP-xylose as donor substrate and the Kms for both zeatin and UDP-xylose are much lower (2 and 3 micromolar, respectively). The chromatographic behavior on affinity columns and the molecular weights (approximate Mr 44,000 daltons) of the two enzymes are similar. Results from substrate competition experiments and enzyme separation by anion exchange HPLC indicate a single, distinct, zeatin O-glycosylation enzyme occurs in embryos of each of these Phaseolus species. Close