4,123 research outputs found
True and False Foodplants of \u3ci\u3eCallosamia Promethea\u3c/i\u3e (Lepidoptera: Saturniidae) in Southern Michigan
A survey in 1980 of the associations of over 400 cocoons of Callosamia promethea Drury in vegetation along and adjacent to southern Michigan roadsides gave evidence for seven species of true larval foodplants (not including two others known in the area from other studies) and 17 species of false foodplants, the latter determined by the (1) rarity of their association with cocoons, (2) only one or two cocoons per plant, and (3) their proximity to a well known true foodplant. Three species, sassafras, black cherry, and buttonbush, are evidently the most important true foodplants in this area. Comparisons are made of the foodplants in terms of past literature, geography, and taxonomic relationships
Evaluation of the Importance of Time-Frequency Contributions to Speech Intelligibility in Noise
Recent studies on binary masking techniques make the assumption that each time-frequency (T-F) unit contributes an equal amount to the overall intelligibility of speech. The present study demonstrated that the importance of each T-F unit to speech intelligibility varies in accordance with speech content. Specifically, T-F units are categorized into two classes, speech-present T-F units and speech-absent T-F units. Results indicate that the importance of each speech-present T-F unit to speech intelligibility is highly related to the loudness of its target component, while the importance of each speech-absent T-F unit varies according to the loudness of its masker component. Two types of mask errors are also considered, which include miss and false alarm errors. Consistent with previous work, false alarm errors are shown to be more harmful to speech intelligibility than miss errors when the mixture signal-to-noise ratio (SNR) is below 0 dB. However, the relative importance between the two types of error is conditioned on the SNR level of the input speech signal. Based on these observations, a mask-based objective measure, the loudness weighted hit-false, is proposed for predicting speech intelligibility. The proposed objective measure shows significantly higher correlation with intelligibility compared to two existing mask-based objective measures
Das UN-Übereinkommen über die Rechte des Kindes und das KJHG: Impulse zur Kindeswohlverwrklichung.
Modeling of Wind Turbine Gearbox Mounting
In this paper three bushing models are evaluated to find a best practice in modeling the mounting of wind turbine gearboxes. Parameter identification on measurements has been used to determine the bushing parameters for dynamic simulation of a gearbox including main shaft. The stiffness of the main components of the gearbox has been calculated. The torsional stiffness of the main shaft, gearbox and the mounting of the gearbox are of same order of magnitude, and eigenfrequency analysis clearly reveals that the stiffness of the gearbox mounting is of importance when modeling full wind turbine drivetrains
Static and Dynamic Critical Behavior of a Symmetrical Binary Fluid: A Computer Simulation
A symmetrical binary, A+B Lennard-Jones mixture is studied by a combination
of semi-grandcanonical Monte Carlo (SGMC) and Molecular Dynamics (MD) methods
near a liquid-liquid critical temperature . Choosing equal chemical
potentials for the two species, the SGMC switches identities () to generate well-equilibrated configurations of the system on
the coexistence curve for and at the critical concentration, ,
for . A finite-size scaling analysis of the concentration susceptibility
above and of the order parameter below is performed, varying the
number of particles from N=400 to 12800. The data are fully compatible with the
expected critical exponents of the three-dimensional Ising universality class.
The equilibrium configurations from the SGMC runs are used as initial states
for microcanonical MD runs, from which transport coefficients are extracted.
Self-diffusion coefficients are obtained from the Einstein relation, while the
interdiffusion coefficient and the shear viscosity are estimated from
Green-Kubo expressions. As expected, the self-diffusion constant does not
display a detectable critical anomaly. With appropriate finite-size scaling
analysis, we show that the simulation data for the shear viscosity and the
mutual diffusion constant are quite consistent both with the theoretically
predicted behavior, including the critical exponents and amplitudes, and with
the most accurate experimental evidence.Comment: 35 pages, 13 figure
Density of states of helium droplets
Accurate analytical expressions for the state densities of liquid He-4
droplets are derived, incorporating the ripplon and phonon degrees of freedom.
The microcanonical temperature and the ripplon angular momentum level density
are also evaluated. The approach is based on inversions and systematic
expansions of canonical thermodynamic properties.Comment: 20 pages, 5 figure
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Linking seasonal forecasts into RiskView to enhance food security contingency planning
RiskView is a tool developed by the World Food Programme (WFP) to translate weather data
(real-time and historical) and other spatial information (e.g., crops, drought risk, population, etc.)
into food security needs and response costs. It serves as a swift way of estimating costs in
advance of food insecurity outlooks for financial planning, and for facilitating better resource
allocations to disasters before on-the-ground needs assessments are produced
Critical Dynamics in a Binary Fluid: Simulations and Finite-size Scaling
We report comprehensive simulations of the critical dynamics of a symmetric
binary Lennard-Jones mixture near its consolute point. The self-diffusion
coefficient exhibits no detectable anomaly. The data for the shear viscosity
and the mutual-diffusion coefficient are fully consistent with the asymptotic
power laws and amplitudes predicted by renormalization-group and mode-coupling
theories {\it provided} finite-size effects and the background contribution to
the relevant Onsager coefficient are suitably accounted for. This resolves a
controversy raised by recent molecular simulations.Comment: 4 pages, 4 figure
Temperature dependence of spatially heterogeneous dynamics in a model of viscous silica
Molecular dynamics simulations are performed to study spatially heterogeneous
dynamics in a model of viscous silica above and below the critical temperature
of the mode coupling theory, . Specifically, we follow the evolution
of the dynamic heterogeneity as the temperature dependence of the transport
coefficients shows a crossover from non-Arrhenius to Arrhenius behavior when
the melt is cooled. It is demonstrated that, on intermediate time scales, a
small fraction of oxygen and silicon atoms are more mobile than expected from a
Gaussian approximation. These highly mobile particles form transient clusters
larger than that resulting from random statistics, indicating that dynamics are
spatially heterogeneous. An analysis of the clusters reveals that the mean
cluster size is maximum at times intermediate between ballistic and diffusive
motion, and the maximum size increases with decreasing temperature. In
particular, the growth of the clusters continues when the transport
coefficients follow an Arrhenius law. These findings imply that the structural
relaxation in silica cannot be understood as a statistical bond breaking
process. Though the mean cluster sizes for silica are at the lower end of the
spectrum of values reported in the literature, we find that spatially
heterogeneous dynamics in strong and fragile glass formers are similar on a
qualitative level. However, different from results for fragile liquids, we show
that correlated particle motion along quasi one-dimensional, string-like paths
is of little importance for the structural relaxation in this model of silica,
suggesting that string-like motion is suppressed by the presence of covalent
bonds.Comment: 13 pages, 11 figure
Superparamagnetic iron oxide polyacrylic acid coated {\gamma}-Fe2O3 nanoparticles does not affect kidney function but causes acute effect on the cardiovascular function in healthy mice
This study describes the distribution of intravenously injected polyacrylic
acid (PAA) coated {\gamma}-Fe2O3 NPs (10 mg kg-1) at the organ, cellular and
subcellular levels in healthy BALB/cJ mice and in parallel addresses the
effects of NP injection on kidney function, blood pressure and vascular
contractility. Magnetic resonance imaging (MRI) and transmission electron
microscopy (TEM) showed accumulation of NPs in the liver within 1h after
intravenous infusion, accommodated by intracellular uptake in endothelial and
Kupffer cells with subsequent intracellular uptake in renal cells, particularly
the cytoplasm of the proximal tubule, in podocytes and mesangial cells. The
renofunctional effects of NPs were evaluated by arterial acid-base status and
measurements of glomerular filtration rate (GFR) after instrumentation with
chronically indwelling catheters. Arterial pH was 7.46 and 7.41 in mice 0.5 h
after injections of saline or NP, and did not change over the next 12h. In
addition, the injections of NP did not affect arterial PCO2 or [HCO3-] either.
Twenty-four and 96h after NP injections, the GFR averaged 11.0 and 13.0 ml
min-1 g-1, respectively, values which were statistically comparable with
controls (14.0 and 14.0 ml min-1 g-1). Mean arterial blood pressure (MAP)
decreased 12-24h after NP injections (111 vs 123 min-1) associated with a
decreased contractility of small mesenteric arteries revealed by myography to
characterise endothelial function. In conclusion, our study demonstrates that
accumulation of superparamagnetic iron oxide nanoparticles does not affect
kidney function in healthy mice but temporarily decreases blood pressure.Comment: 21 pages, 12 figures, published in Toxicology and Applied
Pharmacology 201
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