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Spilonota ocellana (Denis and Schiffermüller) (Lepidoptera: Tortricidae) can be a serious pest of organic apples (Malus domestica Borkhausen (Rosaceae)) in British Columbia, Canada. Recent discovery that S. ocellana moths are attracted by a lure combining acetic acid (AA) and benzyl nitrile (BN), identified as a caterpillar-induced apple leaf volatile, provides an opportunity to develop bisexual mass-trapping or monitoring systems. Sticky white delta traps baited with benzyl nitrile (10 mg/red rubber septum) and an acetic-acid co-lure (3 mL AA/3-mm open 8-mL vial) caught significantly more moths than either component alone. Acetic-acid co-lures were weakly attractive but benzyl-nitrile-loaded septa were not attractive. Moth catches with AA+BN lures were unaffected by the size and type of rubber septum used to release benzyl nitrile, but catches increased with increasing loads of benzyl nitrile. Male and total moth catches were maximised using membrane release devices loaded with a mixture of benzyl nitrile and a second caterpillar-induced volatile, 2-phenylethanol (PET), in combination with an acetic-acid co-lure (AA+BN-PET). Female catches with AA+BN-PET and AA+BN lures were equivalent. Placing AA+BN lures in traps baited with female sex pheromone lures reduced male catches, but female catches were unchanged. When sticky liners were replaced weekly, white delta traps baited with AA+BN lures caught more moths than similarly baited white Multipher®-I bucket traps, or transparent UnitrapsTM. Multipher-I traps with a propylene glycol killing agent (250 mL) caught more moths than those with Vapona insecticide strips. In apple orchards treated with mating disruption sex pheromones, traps baited with AA+BN caught slightly more total moths than traps baited with sex pheromone. Weekly, total male+female moth catches with either AA+BN or sex pheromone lures showed similar seasonal patterns in both untreated and pheromone-disrupted orchards, respectively. Long-lasting release devices and an organic killing agent are needed to develop certified organic mass-trapping technologies for management of S. ocellana with the AA+BN kairomone.
Pandemis limitata (Robinson) (Lepidoptera: Tortricidae) is one of several leaf-feeding caterpillar pests of commercial tree-fruit crops in British Columbia, Canada. Recent discovery that European Pandemis Hübner species are attracted by lures combining acetic acid and the caterpillar-induced apple-leaf volatiles, 2-phenylethanol, and phenylacetonitrile, prompted our examination of P. limitata response to these compounds. Trapping tests in organic apple orchards revealed that neither of these individual benzenoids, nor their binary combination, was attractive. Acetic acid alone was weakly attractive, but more importantly, catches increased significantly when an acetic-acid co-lure was combined with 2-phenylethanol or phenylacetonitrile, individually and together. Catches of male and female P. limitata with acetic acid+2-phenylethanol, or acetic acid+2-phenylethanol+phenylacetonitrile were similar, respectively, and both sexes were caught significantly less often in traps baited with acetic acid+phenylacetonitrile. When combined with acetic-acid co-lures, traps baited with membrane dispensers releasing 2-phenylethanol at ~1 mg/day caught significantly more moths than traps baited with rubber septa lures releasing 2-phenylethanol at ~0.6 mg/day. Moth catches in traps baited with 2-phenylethanol were unaffected when the emission of acetic-acid co-lures was increased from ~28 to 63 mg/day. Catches of male P. limitata in traps baited with sex pheromone were significantly greater than catches in traps baited with acetic acid+2-phenylethanol, or traps baited with a ternary blend of acetic acid+2-phenylethanol+sex pheromone. Catches of female P. limitata in traps baited with acetic acid+2-phenylethanol were significantly reduced when it was combined with sex pheromone. Use of the ternary acetic acid+2-phenylethanol+phenylacetonitrile blend provides an opportunity to develop multispecies bisexual trapping systems to improve management of sympatric tortricid pests currently causing economic losses in organic apples in British Columbia. More work on long-lasting release devices, nonsaturating traps, and organically acceptable killing agents are needed to develop organic mass-trapping systems.
Continual low-level exposure of sheep to the helminth Teladorsagia circumcincta elicits a temporary protective immunity, where factors in the immune abomasal mucosa prevent penetration of infective larvae, but which is essentially lost within 6 weeks of cessation of parasite challenge. Here, a proteomic approach was used to identify proteins that are differentially regulated in immune compared to naïve sheep, as potential key mediators of immunity. Six naïve sheep and 12 sheep trickle-infected with T. circumcincta were treated with anthelmintic, and the naïve (control) and 6 immune sheep were killed 7 days later. The remaining 6 sheep (immune waning) were killed 42 days after anthelmintic treatment. Abomasal tissue samples were subjected to 2D-gel electrophoresis and densitometric analysis. Selected spots (n=73) were identified by peptide mass fingerprinting and confirmatory Western blotting was carried out for 10 proteins. Spots selectively up-regulated in immune versus control, but not immune waning versus control sheep, included galectin-15 and thioredoxin, which were confirmed by Western blotting. In immune sheep, serum albumin was significantly down-regulated and albumin proteolytic cleavage fragments were increased compared to controls. Unexpectedly, albumin mRNA was relatively highly expressed in control mucosa, down-regulated in immune, and was immunolocalized to mucus-producing epithelial cells. Thus we have identified differential expression of a number of proteins following T. circumcincta trickle infection that may play a role in host protection and inhibition of parasite establishment.
This is a two-year elementary college physics course for students majoring in science and engineering. The intention of the writers has been to present elementary physics as far as possible in the way in which it is used by physicists working on the forefront of their field. We have sought to make a course which would vigorously emphasize the foundations of physics. Our specific objectives were to introduce coherently into an elementary curriculum the ideas of special relativity, of quantum physics, and of statistical physics.
This course is intended for any student who has had a physics course in high school. A mathematics course including the calculus should be taken at the same time as this course.
There are several new college physics courses under development in the United States at this time. The idea of making a new course has come to many physicists, affected by the needs both of the advancement of science and engineering and of the increasing emphasis on science in elementary schools and in high schools. Our own course was conceived in a conversation between Philip Morrison of Cornell University and C. Kittel late in 1961. We were encouraged by John Mays and his colleagues of the National Science Foundation and by Walter C. Michels, then the Chairman of the Commission on College Physics. An informal committee was formed to guide the course through the initial stages.
This article examines Frank Tannenbaum's engagement with Mexico in the crucial years following the Revolution of 1910–1920 and his first visit to the country in 1922. Invited—and feted—by the government and its powerful labor allies, Tannenbaum soon expanded his initial interest in organized labor and produced a stream of work dealing with trade unions, peasants, Indians, politics, and education—work that described and often justified the social program of the Revolution, and that, rather surprisingly, continued long after the Revolution had lost its radical credentials in the 1940s. Tannenbaum's vision of Mexico was culturalist, even essentialist; more Veblenian than Marxist; at times downright folkloric. But he also captured important aspects of the process he witnessed: local and regional variations, the unquantifiable socio-psychological consequences of revolution, and the prevailing concern for order and stability. In sum, Tannenbaum helped establish the orthodox—agrarian, patriotic, and populist—vision of the Revolution for which he has been roundly, if sometimes excessively, criticized by recent “revisionist” historians; yet his culturalist approach, with its lapses into essentialism, oddly prefigures the “new cultural history” that many of these same historians espouse.
A multinomial logit is utilized to model the choice of whether to purchase yield or revenue insurance using subjectively elicited survey data. Our results indicate that the demand for crop insurance is inelastic (−0.40), consistent with most earlier yield elasticity estimates, but the elasticity for choices between yield and revenue insurance is found to be relatively more elastic (−0.88).
This article examines farmers’ preferences for various risk management information sources. Our results suggest that information from risk management experts, in-depth materials studied on their own, and popular press outlets tend to be preferred and are ranked highly by producers. Using a regression model to investigate farmer/farm attributes that affect preference for a particular risk management information source, we find that younger farmers with college education, higher leverage, assets greater than $1 million, risk-loving attitudes, and who have used professional services (marketing consultants) tend to prefer information from risk management experts, the Internet, and marketing clubs/other producers. On the other hand, producers who prefer self-study of educational materials and popular press information sources tend to be younger, with lower leverage levels, and have used fewer professional services.
Hog producers in Indiana and Nebraska were surveyed about sources of risk, effectiveness of risk management strategies, and prior participation in and desire for additional risk management education. Ownership of hogs by the producer, size of the operation, and age did have significant effects on ratings of both sources of risk and effectiveness of risk management strategies. Probit analysis found age, prior attendance, knowledge and prior use of the tool, level of integration, and concern about price and performance risk have significant effects on interest in further education about production contracts, futures and options, packer marketing contracts, and financial management.
Brisbane used to be called the Deep North. It spoke of a place where time passed slowly in the summer heat, where rednecks ran the parliament and the press, blacks died from beatings and the police thought themselves above the law. Even though Brisbane is situated in the bottom southeast quarter of the great northern state of Queensland, its sobriquet represented a state of mind.