The Experts below are selected from a list of 300 Experts worldwide ranked by ideXlab platform
Patrick M. Guerin - One of the best experts on this subject based on the ideXlab platform.
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Time-activity budgets and space structuring by the different life stages ofVarroa jacobsoni in capped brood of the honey bee,Apis mellifera
Journal of Insect Behavior, 1997Co-Authors: Gerard Donze, Patrick M. GuerinAbstract:Varroa jacobsoni reproduces in honey bee brood cells. Here the behavioral activity and use of space by infesting Varroa females and progeny were quantified in transparent artificial brood cells. The time-activity budget of both infesting and developing mites converged toward a stable pattern which was established during the bee prepupal stage of the infesting mites and the protonymphal stage of mite progeny. The pattern was such that infesting females and offspring eventually divided their activity between the fecal accumulation on the cell wall, which served as the rendezvous site for newly molted individuals, and the feeding site prepared on the pupa by the foundress. Other parts of the cell wall were used for oviposition and molting, away from the fecal accumulation on which activity of mobile stages was concentrated. Space structuring and the time-activity budget in Varroa probably evolved to enhance the number of fertilized females produced within the capped brood, where space and time are limiting factors. These behavioral adaptations parallel those of other mite species which show group behavior within cavities.
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time activity budgets and space structuring by the different life stages of varroa jacobsoni in capped brood of the honey bee apis mellifera
Journal of Insect Behavior, 1997Co-Authors: Gerard Donze, Patrick M. GuerinAbstract:Varroa jacobsoni reproduces in honey bee brood cells. Here the behavioral activity and use of space by infestingVarroa females and progeny were quantified in transparent artificial brood cells. The time-activity budget of both infesting and developing mites converged toward a stable pattern which was established during the bee prepupal stage of the infesting mites and the protonymphal stage of mite progeny. The pattern was such that infesting females and offspring eventually divided their activity between the fecal accumulation on the cell wall, which served as the rendezvous site for newly molted individuals, and the feeding site prepared on the pupa by the foundress. Other parts of the cell wall were used for oviposition and molting, away from the fecal accumulation on which activity of mobile stages was concentrated. Space structuring and the time-activity budget inVarroa probably evolved to enhance the number of fertilized females produced within the capped brood, where space and time are limiting factors. These behavioral adaptations parallel those of other mite species which show group behavior within cavities.
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Behavioral attributes and parental care of Varroa mites parasitizing honeybee brood
Behavioral Ecology and Sociobiology, 1994Co-Authors: Gerard Donze, Patrick M. GuerinAbstract:Varroa jacobsoni , an ectoparasite of the Asian honeybee Apis cerana , has been introduced world-wide, and is currently decimating colonies of the European honeybee Apis mellifera . Varroa 's reproductive cycle is tuned to that of drone cells, those mainly parasitized in the original host. We describe here how a single fertilized female, infesting a brood cell, can produce two to four adult fertilized females within the limited time span of bee development (270 h in worker and 320 h in drone cells), despite the disturbance caused by cocoon spinning and subsequent morphological changes of the bee. From observations on transparent artificial cells we were able to show how the mite combats these problems with specialized behaviors that avoid destruction by the developing bee, prepares a feeding site for the nymphs on the bee pupa, and constructs a fecal accumulation on the cell wall which serves as a rendezvous site for matings between its offspring. The proximity of the fecal accumulation to the feeding site facilitates feeding by the maturing progeny. However, communal use of the feeding site leads to competition between individuals, and protonymphs are most disadvantaged. This competition is somewhat compensated by the timing of oviposition by the mites. Use of a common rendezvous and feeding site by two or more Varroa mothers in multiinfested cells may have developed from the parental care afforded to them as nymphs.
Scott A. Strobel - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of the ribosomal P-Site substrate CCA-pcb.
Organic letters, 2006Co-Authors: Minghong Zhong, Scott A. StrobelAbstract:[reaction: see text] CCA-pcb (cytidylyl-(3'5')-cytidylyl-(3'5')-3'(2')-O-(N-(6-D-(+)-biotinoylaminohexanoyl)-L-phenylalanyl)adenosine), a ribosomal P-Site substrate, was synthesized by phosphoramidite chemistry in 26 steps with an overall yield of 18%, starting from biotin. The synthesis relies on the judicious selection of orthogonal silyl protecting groups for the 5'-hydroxyls and acid-labile protecting groups (DMTr, AcE, and MeE) at other reactive sites to ensure the intactness of the labile ester. Both 3'-esterification and nucleotide coupling were accomplished by in situ activation with imidazolium ions.
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Synthesis of the ribosomal P-Site substrate CCA-pcb.
Organic letters, 2006Co-Authors: Minghong Zhong, Scott A. StrobelAbstract:CCA-pcb (cytidylyl-(3‘5‘)-cytidylyl-(3‘5‘)-3‘(2‘)-O-(N-(6-d-(+)-biotinoylaminohexanoyl)-l-phenylalanyl)adenosine), a ribosomal P-Site substrate, was synthesized by phosphoramidite chemistry in 26 steps with an overall yield of 18%, starting from biotin. The synthesis relies on the judicious selection of orthogonal silyl protecting groups for the 5‘-hydroxyls and acid-labile protecting groups (DMTr, AcE, and MeE) at other reactive sites to ensure the intactness of the labile ester. Both 3‘-esterification and nucleotide coupling were accomplished by in situ activation with imidazolium ions.
Christopher T Westfall - One of the best experts on this subject based on the ideXlab platform.
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brown recluse spider bite to the eyelid
Ophthalmology, 2000Co-Authors: Robert M Jarvis, Mark V Neufeld, Christopher T WestfallAbstract:Abstract Purpose To present a photographically documented case of a known brown recluse spider bite to the eyelid. Design Interventional case report. Methods The wound was photographed daily during an 11-day hospitalization and at 1 month and 6 months after the injury. Treatment included canthotomy and cantholysis; administration of dapsone, antibiotics, and steroids; and hyperbaric oxygen therapy. Main outcome measures Clinical presentation and course of a known brown recluse spider bite. Results Complete recovery with cicatrization at the site of the bite. Conclusions We present a case of a brown recluse spider bite to the left lower eyelid with a discussion of management and outcome of this rarely reported injury.
Gerard Donze - One of the best experts on this subject based on the ideXlab platform.
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Time-activity budgets and space structuring by the different life stages ofVarroa jacobsoni in capped brood of the honey bee,Apis mellifera
Journal of Insect Behavior, 1997Co-Authors: Gerard Donze, Patrick M. GuerinAbstract:Varroa jacobsoni reproduces in honey bee brood cells. Here the behavioral activity and use of space by infesting Varroa females and progeny were quantified in transparent artificial brood cells. The time-activity budget of both infesting and developing mites converged toward a stable pattern which was established during the bee prepupal stage of the infesting mites and the protonymphal stage of mite progeny. The pattern was such that infesting females and offspring eventually divided their activity between the fecal accumulation on the cell wall, which served as the rendezvous site for newly molted individuals, and the feeding site prepared on the pupa by the foundress. Other parts of the cell wall were used for oviposition and molting, away from the fecal accumulation on which activity of mobile stages was concentrated. Space structuring and the time-activity budget in Varroa probably evolved to enhance the number of fertilized females produced within the capped brood, where space and time are limiting factors. These behavioral adaptations parallel those of other mite species which show group behavior within cavities.
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time activity budgets and space structuring by the different life stages of varroa jacobsoni in capped brood of the honey bee apis mellifera
Journal of Insect Behavior, 1997Co-Authors: Gerard Donze, Patrick M. GuerinAbstract:Varroa jacobsoni reproduces in honey bee brood cells. Here the behavioral activity and use of space by infestingVarroa females and progeny were quantified in transparent artificial brood cells. The time-activity budget of both infesting and developing mites converged toward a stable pattern which was established during the bee prepupal stage of the infesting mites and the protonymphal stage of mite progeny. The pattern was such that infesting females and offspring eventually divided their activity between the fecal accumulation on the cell wall, which served as the rendezvous site for newly molted individuals, and the feeding site prepared on the pupa by the foundress. Other parts of the cell wall were used for oviposition and molting, away from the fecal accumulation on which activity of mobile stages was concentrated. Space structuring and the time-activity budget inVarroa probably evolved to enhance the number of fertilized females produced within the capped brood, where space and time are limiting factors. These behavioral adaptations parallel those of other mite species which show group behavior within cavities.
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Behavioral attributes and parental care of Varroa mites parasitizing honeybee brood
Behavioral Ecology and Sociobiology, 1994Co-Authors: Gerard Donze, Patrick M. GuerinAbstract:Varroa jacobsoni , an ectoparasite of the Asian honeybee Apis cerana , has been introduced world-wide, and is currently decimating colonies of the European honeybee Apis mellifera . Varroa 's reproductive cycle is tuned to that of drone cells, those mainly parasitized in the original host. We describe here how a single fertilized female, infesting a brood cell, can produce two to four adult fertilized females within the limited time span of bee development (270 h in worker and 320 h in drone cells), despite the disturbance caused by cocoon spinning and subsequent morphological changes of the bee. From observations on transparent artificial cells we were able to show how the mite combats these problems with specialized behaviors that avoid destruction by the developing bee, prepares a feeding site for the nymphs on the bee pupa, and constructs a fecal accumulation on the cell wall which serves as a rendezvous site for matings between its offspring. The proximity of the fecal accumulation to the feeding site facilitates feeding by the maturing progeny. However, communal use of the feeding site leads to competition between individuals, and protonymphs are most disadvantaged. This competition is somewhat compensated by the timing of oviposition by the mites. Use of a common rendezvous and feeding site by two or more Varroa mothers in multiinfested cells may have developed from the parental care afforded to them as nymphs.
Gary L Hein - One of the best experts on this subject based on the ideXlab platform.
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Wheat streak mosaic virus coat protein is a determinant for vector transmission by the wheat curl mite.
Virology, 2017Co-Authors: Satyanarayana Tatineni, Anthony J. Mcmechan, Gary L HeinAbstract:Abstract Wheat streak mosaic virus (WSMV; genus Tritimovirus; family Potyviridae), is transmitted by the wheat curl mite (Aceria tosichella Keifer). The requirement of coat protein (CP) for WSMV transmission by the wheat curl mite was examined using a series of viable deletion and point mutations. Mite transmission of WSMV was completely abolished with deletions comprising CP amino acids 58–100. In contrast, the amino-proximal (amino acids 6–27 and 36–57) and carboxy-terminal (14 amino acids) regions of CP were expendable for mite transmission. Mutation of aspartic acid residues at amino acid positions 289 or 326 (D289A or D326A) at the carboxy-proximal region of CP significantly reduced mite transmission. Remarkably, every wheat plant infected by mutants D289A or D326A through mite transmission but not with in vitro transcripts contained a second-site mutation of R131C and N275H, respectively. Collectively, these data demonstrate for the first time that CP is a determinant for an eriophyid-transmitted plant virus.
