730 research outputs found

    Pupal and Adult Parameters as Potential Indicators of Cottonwood Leaf Beetle (Coleoptera: Chrysomelidae) Fecundity and Longevity

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    Cottonwood leaf beetle, Chrysomela scripta, pupae from a laboratory colony were weighed and monitored through adult emergence, oviposition, and mortality to determine if correlations existed between various pupal or adult parameters and fecundity or longevity. Forty-three female cottonwood leaf beetles were monitored. Pupal weight was not a good indicator of fecundity, total oviposition events, number of eggs/beetle/day, or adult longevity. In addition, adult weight showed very low correlation with fecundity, adult longevity, total oviposition events, or number of eggs/beetle/day. However, adult weight was a marginal indicator of the number of eggs/beetle/day, and correlated well with adult body length. Adult longevity could be used to predict fecundity

    Phenology and Infestation Patterns of the Cottonwood Twig Borer (Lepidoptera: Tortricidae) in Iowa

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    Cottonwood twig borer, Gypsonoma haimbachiana (Lepidoptera: Totricidae), phenology and infestation patterns on Populus spp. were examined over a 2-year period in Iowa. Weekly sampling of infested shoots during the host growing season verified the existence of five instars. Head capsule size increased nonlinearly from the first to the fifth instar and corresponded to a concomitant geometric increase in the volume of larval feeding galleries. The sampling indicated that the cottonwood twig borer had two generations per year in Iowa. Corresponding with the two generations, two peaks of larval abundance were observed; one in the second week of June and the other in the first week of August. Greater volume of feeding galleries occurred in the early season generation compared with the late season generation. Sampling of infested shoots revealed that more than 80% of infested terminals contained only one active attack (freshly bored hole in tree terminal with frass present); more than 88% of feeding galleries contained only one larva; and more than 80% of the larvae were found in the first active attack nearest the terminal apex. These data were compared with results published on the phenology and attack patterns of the cottonwood twig borer in the southern United States

    West Chester University Emerald Ash Borer Plan, West Chester, PA

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    Rhombohedral fluoroberyllium borate crystals and hydrothermal growth thereof for use in laser and non-linear optical applications and devices

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    Single, acentric, rhombohedral, fluoroberyllium borate crystals of a size sufficient for use in a variety of laser and non-optical applications are formed by a hydrothermal method

    Effect of surface waviness on a supercritical laminar-flow-control airfoil

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    Calculations were made of the effects of surface waviness on the external pressure of a supercritical airfoil at design conditions. Wave parameters varied include amplitude, wavelength, phase, and number of cycles. Effects of single and multiple waves are calculated at various chordwise locations. General trends of surface waviness effects on pressure distribution are determined and these solutions are reported. Contour deviations are imposed on the upper surface of the airfoil. Results are presented in a manner designed to facilitate ready comparison with the ideal contour static pressure distribution

    Moisture Content and Specific Gravity of The Four Major Southern Pines Under The Same Age and Site Conditions

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    Slash, loblolly, longleaf, and shortleaf pines in northern Louisiana were examined for differences in moisture content (MC) and basic specific gravity (SG) of wood and bark in the complete tree, root, stem, and branches and differences in diameter at breast height (dbh), total height, and taproot length of trees in even-aged plantations under identical site conditions, planting densities, and management practices. The four species did not differ statistically in stemwood, branchwood, or complete-tree wood SG on any of the three sites examined (wet, intermediate, and dry). Shortleaf had a significantly higher rootwood SG on all sites. The wet site generally produced wood with a lower SG, and the dry site produced wood with a higher SG. Differences among species in MC appeared dependent upon the tree component and site condition, while intersite differences in MC were generally component and species dependent. No significant difference among the four species was detected for dbh, total height, or taproot length on the dry or intermediate site. Shortleaf on the wet site produced a significantly shorter stem and taproot than the other species. Tallest trees grew on the intermediate site

    Booster Obsolescence and Life Extension (BOLE) for Space Launch System (SLS)

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    A human mission to the moon and Mars is the stated space exploration goal of the United States and the international community. To achieve these goals, NASA is developing the Space Launch System (SLS) and the Orion crew capsule as key elements in the architecture for missions to the moon and Mars. As part of the SLS Booster Obsolescence and Life Extension (BOLE) program, Northrop Grumman Space Systems is working to address booster obsolescence issues in design and manufacturing. The upgraded boosters will also provide increased performance that will benefit future lunar campaigns, science missions, and the eventual Mars campaign

    Pupal and Adult Parameters as Potential Indicators of Cottonwood Leaf Beetle (Coleoptera: Chrysomelidae) Fecundity and Longevity

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    Cottonwood leaf beetle, Chrysomela scripta, pupae from a laboratory colony were weighed and monitored through adult emergence, oviposition, and mortality to determine if correlations existed between various pupal or adult parameters and fecundity or longevity. Forty-three female cottonwood leaf beetles were monitored. Pupal weight was not a good indicator of fecundity, total oviposition events, number of eggs/beetle/day, or adult longevity. In addition, adult weight showed very low correlation with fecundity, adult longevity, total oviposition events, or number of eggs/beetle/day. However, adult weight was a marginal indicator of the number of eggs/beetle/day, and correlated well with adult body length. Adult longevity could be used to predict fecundity

    Nurse-based restoration of degraded tropical forests with tussock grasses: Experimental support from the Andean cloud forest

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    10 páginas.-- 5 figuras.-- 1 tabla.-- 45 referencias.-- Supporting Information Additional Supporting Information may be found in the online versionof this article. Fig. S1. Performance of palm seedlings in each treatment. Fig. S2. Influence of light intensity on VPD. http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12311/suppinfo© 2014 British Ecological Society. The degradation of the Andean cloud forest raises strong biological conservation issues and threatens the sustainability of a crucial water resource. The idea that nurse-based restoration can accelerate the recovery of these forests is underexplored, despite its promise as a restoration technique. Recent conceptual models predict that facilitation among plants may be an important mechanism, but there is a lack of strong empirical support. We gathered experimental data to test this prediction and explore the relevance of using nurse-based forest restoration in these environments. A 20-month factorial experimental design in the Andean tropical cloud forest was established. We measured the survival and estimated the biomass production of transplanted seedlings of a keystone canopy forest species, Ceroxylon echinulatum (Arecaceae), in a deforested area in the presence/absence of herbivory, a potential nurse plant (the tussock grass Setaria sphacelata, Poaceae) and artificial shade. The joint effects of deforestation and herbivory led to the death of all seedlings, whereas most seedlings survived in the adjacent forest, which was used as the control. The presence of nurse plants led to significantly higher survival and growth of Ceroxylon seedlings throughout the experiment, regardless of herbivore presence. The nurse effects were explained by a reduction of the relative abiotic stress experienced by the seedlings outside the forest, that is, the consistently decreasing maximum vapour pressure deficit. Furthermore, nurse tussocks delayed and reduced the effects of herbivory by offering physical protection and a refuge for seedlings against detection by herbivores. However, the effects of herbivory and abiotic stress on facilitation were not additive. Synthesis and applications. Facilitation in degraded cloud forest can be intense as soon as the beneficiary plants are driven away from their physiological optimum (relative abiotic stress) and/or are confronted by herbivory. Using pre-established exotic tussock grasses as a nurse-based restoration technique in degraded cloud forest is a low-cost, non-detrimental (to biodiversity) option, especially in the absence of nurse trees and shrubs. The success of this method requires transplanting seedlings at the base of tussocks. Facilitation in degraded cloud forest can be intense as soon as the beneficiary plants are driven away from their physiological optimum (relative abiotic stress) and/or are confronted by herbivory. Using pre-established exotic tussock grasses as a nurse-based restoration technique in degraded cloud forest is a low-cost, non-detrimental (to biodiversity) option, especially in the absence of nurse trees and shrubs. The success of this method requires transplanting seedlings at the base of tussocks.We thank the people of the Inti-Llacta Reserve for their kind reception and J. Lincango, S. Cauvy-Fraunie, and C. Gully for their help with data collection. We are also grateful to P. Liancourt and two anonymous reviewers for extensive comments on the manuscript and to the LucidPapers team for English revision. This research was funded by the Ecuadorian government (ECOFONDO grant no. 019-ECO7-Inv1) and the project PALMS FP7-ENV-2007-I (www.fp7-palms.org).Peer Reviewe
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