1,612 research outputs found
Neonicotinoid insecticides disrupt predation on the eggs of turf-infesting scarab beetles
Turfgrass applications of imidacloprid were previously shown to suppress the abundance of certain soil arthropods. To ascertain whether those impacts harbor functional consequences, the effect of neonicotinoids on Japanese beetle (Popillia japonica Newman) predation was examined in three experiments that measured removal of eggs implanted into non-irrigated field plots. A first experiment confirmed that a single imidacloprid application reduced the abundance of nontarget fauna and the rate of egg removal. A second experiment compared the impacts of imidacloprid with those of three other neonicotinoids, while a third measured the impact of imidacloprid when applied in July, August or September. Egg removal declined 28.3-76.1% in imidacloprid-treated plots across all studies. Effects were detected as early as one week after treatment (WAT) and persisted as long as four WAT. The extent of suppression did not vary across month of application. Clothianidin, dinotefuran and thiamethoxam also suppressed egg removal, and the effects were similar among them and with imidacloprid. There was no discernible association between variation in rainfall and treatment effects, but this was not explicitly tested. Results support the hypotheses that a single neonicotinoid application can suppress predation on pest populations and that the effect does not vary with respect to active ingredient or season of application. Neonicotinoid application at the time of beetle oviposition puts intended effects (mortality of neonates) in conflict with unintended effects (disruption of egg predation). The conservation of predation on early life stages might buffer the reduced efficacy of late season applications that target more advanced instars. As application timing and post-application irrigation affect insecticide performance, they might also be manipulated to reduce nontarget effect
Managing the Risks of Shale Gas Development Using Innovative Legal and Regulatory Approaches
Booming production of oil and gas from shale, enabled by hydraulic fracturing technology, has led to tension between hoped-for economic benefits and feared environmental and other costs, with great associated controversy. Study of how policy can best react to these challenges and how it can balance risk and reward has focused on prescriptive regulatory responses and, to a somewhat lesser extent, voluntary industry best practices. While there is undoubtedly room for improved regulation, innovative tools are relatively understudied. The liability system predates environmental regulation yet still plays an important — and in some senses predominant — role. Changes to that system, including burden-shifting rules and increased bond requirements, might improve outcomes. Similarly, new regulation can and should incorporate modern understanding of the benefits of market-based approaches. Information disclosure requirements can benefit the liability system and have independent benefits of their own. Policymakers faced with a need for policy change in reaction to shale development should carefully consider alternatives to regulation and, when regulation is deemed necessary, consider which tool is best suited
Ignition of a Combustible Solid with Reactant Consumption
The effects of excessive reactant consumption on the ignition of a combustible solid are introduced through a revised scaling of the heat release constant. Large activation energy asymptotics then yields a new one-parameter integral equation governing the temperature evolution near ignition. Analysis of the integral equation reveals a critical value of the parameter which distinguishes between the cases of ignition and nonignition. © 1987 Society for Industrial and Applied Mathematic
Stability of a Viscoelastic Burgers Flow
The system of equations proposed by Burgers to model turbulent flow in a channel is extended to include viscoelastic affects. The stability and bifurcation properties are examined in the neighborhood of the critical Reynolds number. For highly elastic fluids, the bifurcated state is periodic with a shift in frequency
The clustering of galaxies in the SDSS-III Baryon Oscillation Spectroscopic Survey: RSD measurement from the power spectrum and bispectrum of the DR12 BOSS galaxies
We measure and analyse the bispectrum of the final, Data Release 12, galaxy
sample provided by the Baryon Oscillation Spectroscopic Survey, splitting by
selection algorithm into LOWZ and CMASS galaxies. The LOWZ sample contains
361\,762 galaxies with an effective redshift of , and the
CMASS sample 777\,202 galaxies with an effective redshift of . Combining the power spectrum, measured relative to the
line-of-sight, with the spherically averaged bispectrum, we are able to
constrain the product of the growth of structure parameter, , and the
amplitude of dark matter density fluctuations, , along with the
geometric Alcock-Paczynski parameters, the product of the Hubble constant and
the comoving sound horizon at the baryon drag epoch, , and the
angular distance parameter divided by the sound horizon, .
After combining pre-reconstruction RSD analyses of the power spectrum monopole,
quadrupole and bispectrum monopole; with post-reconstruction analysis of the
BAO power spectrum monopole and quadrupole, we find , , for
the LOWZ sample, and ,
, for the CMASS sample. We
find general agreement with previous BOSS DR11 and DR12 measurements. Combining
our dataset with {\it Planck15} we perform a null test of General Relativity
(GR) through the -parametrisation finding
, which is away from the GR
predictions.Comment: 34 pages, 22 figures, 8 tables. Accepted for publication in MNRAS.
Data available at https://sdss3.org//science/boss_publications.ph
Food Availability, Foraging Behavior, and Diet of Autumn Migrant Landbirds in the Boise Foothills of Southwestern Idaho
Food availability and acquisition are critical components of a stopover site\u27s suitability, but we know relatively little about how changes in food availability affect the stopover ecology of migrating landbirds. We examined fruit and arthropod availability in three habitats, studied foraging behavior and diet, and investigated use versus availability for passerines migrating through southwestern Idaho in autumn. Hemiptera dominated foliage-dwelling arthropod communities in all three habitats, whereas Hymenoptera were most numerous among ground-dwelling arthropods. Mountain shrubland had relatively high biomass of both ground-dwelling and foliage-dwelling arthropods, whereas conifer forest had high biomass of foliage-dwelling arthropods only and shrub steppe had high biomass of ground-dwelling arthropods only. Species\u27 foraging behavior varied, but most species foraged in mountain shrubland more often than expected by chance. Diets of most species included a high proportion of certain Hemiptera and Hymenoptera with smaller proportions of Coleoptera, Diptera, and Heteroptera; Coleoptera and some Hemiptera were consistently preferred by most species. Importantly, all 19 bird species examined consumed some fruit, and this is the first documentation of frugivory for two warbler species. These data point to the importance of several arthropod taxa, especially the Hemiptera and Hymenoptera, and fruits to landbirds migrating in mountain shrubland in autumn. Finally, we found no effect of annual variation of fruit or arthropod abundance on migrants\u27 energetic condition, suggesting that food was sufficient for mass gain in all years of this study and/or that foraging behavior may be plastic enough to allow birds to gain mass despite annual differences in food availability
Human Subtilase SKI-1/S1P Is a Master Regulator of the HCV Lifecycle and a Potential Host Cell Target for Developing Indirect-Acting Antiviral Agents
HCV infection is a major risk factor for liver cancer and liver transplantation worldwide. Overstimulation of host lipid metabolism in the liver by HCV-encoded proteins during viral infection creates a favorable environment for virus propagation and pathogenesis. In this study, we hypothesize that targeting cellular enzymes acting as master regulators of lipid homeostasis could represent a powerful approach to developing a novel class of broad-spectrum antivirals against infection associated with human Flaviviridae viruses such as hepatitis C virus (HCV), whose assembly and pathogenesis depend on interaction with lipid droplets (LDs). One such master regulator of cholesterol metabolic pathways is the host subtilisin/kexin-isozyme-1 (SKI-1) – or site-1 protease (S1P). SKI-1/S1P plays a critical role in the proteolytic activation of sterol regulatory element binding proteins (SREBPs), which control expression of the key enzymes of cholesterol and fatty-acid biosynthesis. Here we report the development of a SKI-1/S1P-specific protein-based inhibitor and its application to blocking the SREBP signaling cascade. We demonstrate that SKI-1/S1P inhibition effectively blocks HCV from establishing infection in hepatoma cells. The inhibitory mechanism is associated with a dramatic reduction in the abundance of neutral lipids, LDs, and the LD marker: adipose differentiation-related protein (ADRP)/perilipin 2. Reduction of LD formation inhibits virus assembly from infected cells. Importantly, we confirm that SKI-1/S1P is a key host factor for HCV infection by using a specific active, site-directed, small-molecule inhibitor of SKI-1/S1P: PF-429242. Our studies identify SKI-1/S1P as both a novel regulator of the HCV lifecycle and as a potential host-directed therapeutic target against HCV infection and liver steatosis. With identification of an increasing number of human viruses that use host LDs for infection, our results suggest that SKI-1/S1P inhibitors may allow development of novel broad-spectrum biopharmaceuticals that could lead to novel indirect-acting antiviral options with the current standard of care
Changes in the circumscription of Deprea (Physalideae, Solanaceae): Thirty two new combinations
According to the latest phylogenetic and cytogenetic results, Larnax and Deprea should be merged in order to form a natural group. Consequently, we propose 32 combinations of Larnax species names under Deprea: D. abra-patriciae (S.Leiva & Barboza) S.Leiva & Deanna, comb. nov., D. altomayoensis (S.Leiva & Quip.) Barboza & Deanna, comb. nov., D. andersonii (N.W.Sawyer) Deanna & S.Leiva, comb. nov., D. bongaraensis (S.Leiva) Deanna & Barboza, comb. nov., D. chotanae (S.Leiva, Pereyra & Barboza) S.Leiva, comb. nov., D. darcyana (N.W.Sawyer) Barboza & S.Leiva, comb. nov., D. dilloniana (S.Leiva, Quip. & N.W.Sawyer) Barboza, comb. nov., D. grandiflora (N.W.Sawyer & S.Leiva) Deanna & Barboza, comb. nov., D. harlingiana (Hunz. & Barboza) S.Leiva & Deanna, comb nov., D. hawkesii (Hunz.) Deanna, comb. nov., D. kann-rasmussenii (S.Leiva & Quip.) S.Leiva & Barboza, comb. nov., D. longipedunculata (S.Leiva, E.Rodr. & J.Campos) Barboza, comb. nov., D. lutea (S.Leiva) Deanna, comb. nov., D. macasiana (Deanna, S.Leiva & Barboza) Barboza, comb. nov., D. maculatifolia (E.Rodr. & S.Leiva) S. Leiva, comb. nov., D. nieva (S.Leiva & N.W.Sawyer) Barboza & Deanna, comb. nov., D. parviflora (N.W.Sawyer & S.Leiva) S.Leiva, comb. nov., D. pedrazae (S.Leiva & Barboza) Deanna & S.Leiva, comb. nov., D. peruviana (Zahlbr.) S.Leiva & Barboza, comb. nov., D. pilosa (S.Leiva, E.Rodr. & J.Campos) Deanna, comb. nov., D. pomacochaensis (S.Leiva) Barboza, comb. nov., D. psilophyta (N.W.Sawyer) S.Leiva & Deanna, comb. nov., D. pumila (S.Leiva, Barboza & Deanna) S.Leiva, comb. nov., D. purpurea (S.Leiva) Barboza & S.Leiva, comb. nov., D. purpureocarpa (S.Leiva, Deanna & Barboza) Deanna, comb. nov., D. sachapapa (Hunz.) S.Leiva & Deanna, comb. nov., D. sagasteguii (S.Leiva, Quip. & N. W.Sawyer) Barboza, comb. nov., D. sawyeriana (S.Leiva, E.Rodr. & J.Campos) S.Leiva, comb. nov., D. schjellerupiae (S.Leiva & Quip.) Barboza & Deanna, comb. nov., D. steyermarkii (Hunz.) S.Leiva & Barboza, comb. nov., D. toledoana (Barboza & S.Leiva) Barboza, comb. nov., and D. vasquezii (S.Leiva, E.Rodr. & J.Campos) Deanna, comb. nov.Fil: Deanna, Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Leiva González, Segundo. Universidad Privada Atenor Orrego. Museo de Historia Natural; PerúFil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin
Multi-State Trials of Bt Sweet Corn Varieties for Control of the Corn Earworm (Lepidoptera: Noctuidae)
Field tests in 2010-2011 were performed in New York, Minnesota, Maryland, Ohio, and Georgia to compare Bt sweet corn lines expressing Cry1A.105 + Cry2Ab2 and Cry1Ab with their non-Bt isolines, with and without the use of foliar insecticides. The primary insect pest in all locations during the trial years was Heliocoverpa zea (Boddie), which is becoming the most serious insect pest of sweet corn in the United States. At harvest, the ears were measured for marketability according to fresh market and processing standards. For fresh market and processing, least squares regression showed significant effects of protein expression, state, and insecticide frequency. There was a significant effect of year for fresh market but not for processing. The model also showed significant effects of H. zea per ear by protein expression. Sweet corn containing two genes (Cry1A.105 + Cry2Ab2) and a single gene (Cry1Ab) provided high marketability, and both Bt varieties significantly outperformed the traditional non-Bt isolines in nearly all cases regardless of insecticide application frequency. For pest suppression of H. zea, plants expressing Bt proteins consistently performed better than non-Bt isoline plants, even those sprayed at conventional insecticide frequencies. Where comparisons in the same state were made between Cry1A.105 + Cry2Ab2 and Cry1Ab plants for fresh market, the product expressing Cry1A.105 + Cry2Ab2 provided better protection and resulted in less variability in control. Overall, these results indicate Cry1A.105 + Cry2Ab2 and Cry1Ab plants are suitable for fresh market and processing corn production across a diversity of growing regions and years. Our results demonstrate that Bt sweet corn has the potential to significantly reduce the use of conventional insecticides against lepidopteran pests and, in turn, reduce occupational and environmental risks that arise from intensive insecticide us
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