10,557 research outputs found
Persistence of Jack Pine Budworm \u3ci\u3eChoristoneura Pinus Pinus,\u3c/i\u3e (Lepidoptera: Tortricidae) Egg Mass Chorions on Jack Pine Foliage
More than one-fifth of old and nearly one-half of new jack pine budworm egg mass chorions remained on the foliage after one year, and an experienced observer could not determine accurately the age of one-fourth of them. Counts of new egg masses are used to estimate current populations, and large errors could result
Habitats and Spider Prey of \u3ci\u3eDipogon Sayi Sayi\u3c/i\u3e (Hymenoptera: Pompilidae) in Washington County, Maine
Spider wasps were reared from three types of trap-nests deployed in strip-clearcut areas of a spruce-fir-mixed hardwood forest of Maine. Collections of Dipogon sayi sayi from Mooseborn National Wildlife Refuge, Washington County, represent the easternmost records for the United States. Spider prey included females of Misumena vatia, Xysticus emertoni (new prey record), and X. punctatus, and juveniles and penultimate males of Xysticus sp. We found no evidence of nest-site competition between spider wasps and eumenid wasps (Hymenoptera: Eumenidae) that prey on spruce budwornl, Choristoneura fumiferana, when available nesting sites ranged from 320 to 4400
A Happiness Approach to Cost-Benefit Analysis
Subjective well-being (SWB) surveys ask respondents to quantify their overall or momentary happiness or life-satisfaction, or pose similar questions about other aspects of respondents\u27 mental states. A large empirical literature in economics and psychology has grown up around such surveys. Increasingly, too, scholars have advanced the normative proposal that SWB surveys be used for policymaking—for example, by using survey results to calculate monetary equivalents for nonmarket goods (to be incorporated in cost-benefit analysis), or to calculate gross national happiness.
This Article skeptically evaluates the policy role of SWB data. It is critical to distinguish between (1) using SWB surveys as evidence of preference utility versus (2) using them as evidence of experience utility. Preference utility is a measure of the extent to which someone has realized her preferences; experience utility, a measure of the quality of someone\u27s mental states. The two are quite different because individuals can have preferences regarding non-mental occurrences.
Having drawn this distinction, the Article then argues, first, that SWB surveys are poor evidence of preference utility—given problems of preference and scale heterogeneity, as well as other difficulties. Stated-preference surveys are a much better survey format for eliciting preference utility. Second, in considering SWB surveys as an experience-utility measure, we should recognize that experientialism about well-being—the view that well-being is simply a matter of good experiences—is highly controversial. More plausibly, an experience-utility measure might be seen as an indicator of one aspect of well-being. However, even constructing this weak experience-utility measure is not straightforward—as the Article demonstrates by discussing Daniel Kahneman\u27s detailed proposal for such a metric
Spruce Budworm and Other Lepidopterous Prey of Eumenid Wasps (Hymenoptera: Eumenidae) in Spruce-Fir Forests of Maine
Three species of eumenid wasps, Ancistrocerus adiabatus, Ancistrocerus antilope, and Euodynerus Ieucomelas, accepted and provisioned trap-nesting blocks with lepidopterous larvae, A pyralid. Nephopteryx sp., was the most commonly provisioned prey. A. adiabarus and E. leucomelas preyed on late instars of the spruce budworm, Choristoneura fumiferana: however. budworms accounted for only 6% of the provisioned prey. Estimates of budworm population densities before and after wasp predation, and subsample-s of provisioned prey indicated no significant reductions i = 0.065%) in budworm populations attributable to trap-nesting wasps
Field Tests of Kairomones to Increase Parasitism of Spruce Budworm (Lepidoptera: Tortricidae) Eggs by \u3ci\u3eTrichogramma\u3c/i\u3e Spp. (Hymenoptera: Trichogrammatidae)
Hexane extracts of spruce budworm, Choristoneura fumiferana, moth scales, applied at 0.04 moth-gram equivalents/branch and at 0.06 moth-gram equivalents/tree, failed to increase parasitism rates of Trichogramma spp. in two cutover spruce-fir stands in Maine. Releasing Maine-strain T. minutum apparently increased parasitism rates about 20-fold. However, application of kairomone extracts to whole branches and to upper crowns of small trees may have interfered with host-searching behaviors of Trichogramma parasitoids
Comparison of catalyst activity
Reactions of highly active catalysts are compared by allowing temperature of catalyst bed, initially at 77 K, to increase slowly; marked deviation in smooth warming curve denotes temperature at which detectable reaction occurs. The lower the temperature at which reaction commences, the more active the catalyst
Terricolous Spiders (Araneae) of Insecticide-Treated Spruce-Fir Forests in West-Central Maine
Spiders of 12 families, 42 genera, and at least 62 species were captured in linear-pitfall traps placed in insecticide-treated (Sevin-4-Oil®, Dipel 4L ®, Thuricide 16B®) and untreated spruce-fIr forests of west-central Maine. Species richness per family ranged from 1 (Theridiidae, Araneidae, Salticidae) to 19 (Erigonidae). Most trapped species were web-spinners (67.2%); most trapped individuals were hunters (75.2%). Lycosidae accounted for 66.1 % of all (n = 887) captured spiders. Total trapped spiders varied among insecticide treatments, sampling dates, and study sites. However, comparison of mean prespray and postspray trap catches indicated no significant reduction (ANOVA, ANCOVA, P 0.05) in terricolous spiders following insecticide treatments. Increases in spider abundance during postspray sampling periods may have masked detection of treatment effects
Microstructure versus Size: Mechanical Properties of Electroplated Single Crystalline Cu Nanopillars
We report results of uniaxial compression experiments on single-crystalline Cu nanopillars with nonzero initial dislocation densities produced without focused ion beam (FIB). Remarkably, we find the same power-law size-driven strengthening as FIB-fabricated face-centered cubic micropillars. TEM analysis reveals that initial dislocation density in our FIB-less pillars and those produced by FIB are on the order of 10^(14)  m^(-2) suggesting that mechanical response of nanoscale crystals is a stronger function of initial microstructure than of size regardless of fabrication method
- …