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101.
Indirect Effects of an Existing Wind Energy Facility on Lekking Behavior of Greater Prairie‐Chickens
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Jennifer A. Smith Cara E. Whalen Mary Bomberger Brown Larkin A. Powell 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(5):419-429
Rapid expansion of the wind energy industry has raised concerns about the potential effects of anthropogenic disturbance on prairie grouse. While efforts have been made to address the effects of wind energy facilities on measures of fitness, their effect on the behaviors of prairie grouse has been largely neglected. To address these concerns, we investigated the effects of an existing wind energy facility in Nebraska that became operational in 2005 on the lekking behavior of male greater prairie‐chickens Tympanuchus cupido pinnatus between March and May 2013. Given the potential for disturbance caused by wind turbine noise to disrupt acoustic communication and thus behavior, we predicted that males at leks close to, compared to far from, the wind energy facility would spend more time in agonistic behaviors, and less in booming displays. Given the potential for wind turbine noise to reduce the number of females attending leks (hereafter ‘female lek attendance’), we also predicted that males at leks close to the wind energy facility would spend more time in non‐breeding behaviors and less time in breeding behaviors than males farther from the facility. Although we found no effect of the wind energy facility on female lek attendance, males at leks closer to the wind energy facility spent less time in non‐breeding behaviors than those at leks farther away. However, distance from the wind energy facility had no effect on time spent performing booming displays, flutter jumps, or in agonistic behaviors. Given that lekking behaviors of males influence mating success, our results may have consequences for the fitness of prairie grouse breeding in the vicinity of wind energy facilities. 相似文献
102.
103.
Summary We describe a rapid and easily reproducible modification of the freeze-squeeze method of separating DNA from agarose gels. Our method involves slicing out the agarose gel portion which contains the DNA of interest, freezing this gel slice at –20°C, then centrifuging the frozen slice in a filtration unit which contains a cellulose acetate filter. The agarose is retained on the filter and the filtrate contains the DNA. DNA purified in this manner could be completely digested with restriction endonucleases and completely ligated with DNA ligase, without further purification. The percentages of recovery for various sizes of linear and plasmid double-stranded DNA ranged from 57 to 69%. The procedure takes less than 30 minutes to perform. 相似文献
104.
Molecular cloning and analysis of the CRY1 gene: a yeast ribosomal protein gene. 总被引:22,自引:2,他引:20
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Using cloned DNA from the vicinity of the yeast mating type locus (MAT) as a probe, the wild type allele of the cryptopleurine resistance gene CRY1 has been isolated by the technique of chromosome walking and has been shown to be identical to the gene for ribosomal protein 59. A recessive cryR1 allele has also been cloned, using the integration excision method. The genetic distance from MAT to CRY1 is 2.2 cM, while the physical distance is 21 kb, giving a ratio of about 10 kb/cM for this interval. The phenotypic expression of both plasmid borne alleles of the gene can be detected in vivo. The use of this gene as a hybridization probe to examine RNA processing defects in the rna 2, rna 3, rna 4, rna 8, and rna 11 mutants is also discussed. 相似文献
105.
Recovery of Rauscher Leukemia Virus from Large Volumes of Seeded Cow''s Milk and from Infected Murine Spleens 总被引:2,自引:2,他引:0
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Rauscher murine leukemia virus was used as an indicator agent to develop a methodology for the extraction and concentration of a theoretical leukemia virus from bovine milk and tissues. The indicator virus was seeded into cow's milk or was recovered from infected murine spleens. The tissue homogenates and the defatted milk were processed in a B-XVI rotor of a Spinco L-4 ultracentrifuge at a flow rate of 3 liters/hr. The efficiency of Rauscher virus recovery was greatest when the rotor was used without a gradient. A loss of between 0.6 and 0.7 log of total infectious virus, as determined by the spleen assay method, resulted when the seeded milk and murine spleens were processed. The procedures developed are presently being used in transmission experiments in an attempt to induce leukemia in the bovine. 相似文献
106.
Robert Sullivan John T. Tierney Edward P. Larkin Ralston B. Read Jr. James T. Peeler 《Applied microbiology》1971,22(3):315-320
Thermal destruction rate curves were determined for adenovirus 12, reovirus 1, and herpes simplex virus in sterile milk, raw milk, raw chocolate milk, and raw ice cream mix. At 40 to 60 C, the curves were asymptotic to the base line. At 65 C, which is near the pasteurization standard, the curves approached a first-order reaction. Thermal resistance studies, by means of in vivo assays, of Moloney and Rauscher leukemia viruses and Moloney and Rous sarcoma viruses indicated that Rous sarcoma was the most resistant. A comparison of the 12D processes of Rous sarcoma virus, reovirus 1, adenovirus 12, and herpes simplex virus in ice cream mix (the most protective of the suspending menstrua studied) with the U.S. Public Health Service pasteurization standard indicated an adequate safety factor in current pasteurization practices. 相似文献
107.
P. A. Davies M. A. Pallotta S. A. Ryan W. R. Scowcroft P. J. Larkin 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(5):644-653
Summary The progeny of 551 regenerants of the hexaploid wheat cultivar Millewa were analysed for somaclonal mutants at the threeAdh-1 loci in hexaploid wheat. Seventeen regenerants gave rise to progeny having altered ADH1 zymograms. Progeny with altered zymograms in 13 of these regenerants were aneuploid. The remaining 4 regenerants gave rise to euploid progeny with altered ADH1 zymograms. The genetics of three of these somaclonal mutants is described in detail. These regenerants were interpreted to possess a 4A isochromosome, a 3BS/4A translocation and a 7BS/4A translocation, respectively.This research was partly supported by the Rockefeller Foundation and a Reserve Bank of Australia Rural Credit Development Fund research grant 相似文献
108.
Eyespot Disease of Sugarcane : INDUCTION OF HOST-SPECIFIC TOXIN AND ITS INTERACTION WITH LEAF CELLS 总被引:1,自引:1,他引:0
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Helminthosporium sacchari produces a toxin which is responsible for the symptoms of eyespot disease in Saccharum officinarum. A rapid and highly repeatable bioassay based on increase in conductivity of tissue leachates showed that the interaction of toxin with sugarcane obeys Michaelis-Menten hyperbolic saturation kinetics. There was no evidence for positive or negative cooperation interaction. Resistant and susceptible cultivars of sugar cane had distinctive conductivity characteristics. Co-cultures of H. sacchari and suspension cultures of sugarcane gave up to a 4,000-fold increase in toxin production. 相似文献
109.
110.
Carbohydrate structures of the human-immunodeficiency-virus (HIV) recombinant envelope glycoprotein gp120 produced in Chinese-hamster ovary cells. 总被引:17,自引:0,他引:17
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T Mizuochi M W Spellman M Larkin J Solomon L J Basa T Feizi 《The Biochemical journal》1988,254(2):599-603
The present paper describes the structures of the N-linked oligosaccharides of the human-immunodeficiency-virus (HIV) envelope glycoprotein gp120 (cloned from the HTLV-III B isolate and expressed as a secreted fusion protein after transfection of Chinese-hamster ovary cells), which is known to bind with high affinity to human T4-lymphocytes. Oligosaccharides were released from peptide by hydrazinolysis, fractionated by paper electrophoresis, high-performance lectin-affinity chromatography and Bio-Gel P-4 column chromatography, and their structures determined by sequential exoglycosidase digestions in conjunction with methylation analysis. The glycoprotein was found to be unique in its diversity of oligosaccharide structures. These include high-mannose type and hybrid type, as well as four categories of complex-type chains: mono-, bi-, tri- and tetra-antennary, with or without N-acetyl-lactosamine repeats, and with or without a core-region fucose residue. Among the sialidase-treated oligosaccharides, no less than 29 structures were identified as follows: (formula; see text) where G is galactose, GN is N-acetylglucosamine, M is mannose, F is fucose, and '+/- ' means that residues are present in a proportion of chains. The actual number of oligosaccharide structures is much greater, since before desialylation there was evidence that, among the hybrid and complex-type chains, all but 6% contained sialic acid at the C-3 position of terminal galactose residues, and partially sialylated forms of the bi- and multi-antennary chains were present. Detailed evidence for the proposed oligosaccharide sequences will be published as a supplementary paper [T. Mizuochi, M. W. Spellman, M. Larkin, J. Solomon, L. J. Basa & T. Feizi (1988) Biomed. Chromatogr., in the press]. 相似文献