8,313 research outputs found
Survey of finance companies, 1996
Finance companies are major suppliers of credit to consumers and businesses. The sector is made up of roughly 1,250 nondepository financial institutions, with 20 firms accounting for three-fourths of the receivables. The Federal Reserve System has been surveying the assets and liabilities of finance companies, typically at five-year intervals, since June 1955. This article summarizes the results of the 1996 survey. Special features of that survey are a breakdown of automobile leases into consumer and business components and, relative to previous surveys, greater detail on the composition of real estate credit and more information on securitized loans and leases.Finance companies
High fidelity optogenetic control of individual prefrontal cortical pyramidal neurons in vivo
Precise spatial and temporal manipulation of neural activity in specific
genetically defined cell populations is now possible with the advent of
optogenetics. The emerging field of optogenetics consists of a set of
naturally-occurring and engineered light-sensitive membrane proteins that are
able to activate (e.g., channelrhodopsin-2, ChR2) or silence (e.g.,
halorhodopsin, NpHR) neural activity. Here we demonstrate the technique and the
feasibility of using novel adeno-associated viral (AAV) tools to activate
(AAV-CaMKll{\alpha}-ChR2-eYFP) or silence (AAV-CaMKll{\alpha}-eNpHR3.0-eYFP)
neural activity of rat prefrontal cortical prelimbic (PL) pyramidal neurons in
vivo. In vivo single unit extracellular recording of ChR2-transduced pyramidal
neurons showed that delivery of brief (10 ms) blue (473 nm) light-pulse trains
up to 20 Hz via a custom fiber optic-coupled recording electrode (optrode)
induced spiking with high fidelity at 20 Hz for the duration of recording (up
to two hours in some cases). To silence spontaneously active neurons we
transduced them with the NpHR construct and administered continuous green (532
nm) light to completely inhibit action potential activity for up to 10 seconds
with 100% fidelity in most cases. These versatile photosensitive tools combined
with optrode recording methods provide experimental control over activity of
genetically defined neurons and can be used to investigate the functional
relationship between neural activity and complex cognitive behavior.Comment: 4 pages, 4 figures F1000Research articl
Harvesting, Drying, and Storing Grain Sorghum
Grain sorghum (milo) has been successfully produced in many areas of Kentucky and can be grown in alternating years with soybeans to replace corn in a crop rotation cycle. For most of the past 20 years, it has ranked fourth in production of all grain crops grown in the state and was valued at 1.53 million in 1999 and 2000, respectively. Rotating milo with soybeans can help control soybean cyst nematodes and other pests that suppress yield. It can provide higher yields than corn in dry years, especially on sandy soils. The feed/energy value of milo is similar to corn, so it has been used successfully in balanced rations for beef, poultry, and swine and as a feedstock for ethanol production (Hamman et al., 2001). In fact, the 2002 Farm Bill (USDA, 2002) encourages an increase in the production of grain sorghum because of its use as an ethanol feedstock and the current national interest in reducing foreign oil imports
Permeability of Corn, Soybeans, and Soft Red and White Winter Wheat as Affected by Bulk Density
Darcy’s law is a function of viscosity, permeability, and velocity and can be used to predict the airflow resistance in granular materials at low air velocities. Permeability also governs the magnitude of natural convection currents during periods of non-aerated grain storage. The permeability of corn, soybeans, soft white winter wheat, and soft red winter wheat were measured as a function of bulk density and moisture content. Air was passed through a column of grain and the flow rate and pressure drop measured. Bulk density and kernel density were also measured to determine the porosity of grain in the test column. Two filling methods were used to change the bulk density of grain by approximately 50 kg/m3, an increase of 7%. This resulted in a reduction in porosity of approximately 4 percentage points. However, permeability decreased by a maximum of 45%. Wheat had the lowest permeability (between 1.15 × 10-8 and 7.29 × 10-9 m2 or highest resistance coefficient between 1591 and 2510 Pa.s/m2, respectively, depending on bulk density and moisture content), while corn and soybeans were similar (permeability varied between 1.30 × 10-8 and 3.03 × 10-8 m2 or resistance coefficient between 1,408 and 604 Pa·s/m2, respectively). Experiments were conducted up to an air velocity of 0.0052 m/s that resulted in a Reynolds number of 2.5, which was slightly above the maximum air velocity expected during non-aerated grain storage. Nevertheless, Darcy’s law would be appropriate for predicting natural convection currents during non-aerated storage
Alternative Bait Marker Systems for White-Tailed Deer
We compared alternative bait markers for a study of free-ranging white-tailed deer (Odocoileus virginianus) based on the following criteria: 1) detectability in fecal matter; 2) incorporation into corn bait; 3) palatability; and 4) cost. We used penned sheep (Ovis aries) as an experimental model to evaluate Microtaggants, metallic flakes, plastic chips, and rare earth elements as bait markers, and molasses and soy lecithin as marker adhesives. The metallic flakeÂ-soy lecithin combination best met our criteria. It was also successful in a field study evaluating supplemental feeding on deer behavior and activity in central Wisconsin. Metallic flakes were easily detected under field conditions, readily adhered to shelled corn bait, enabled assessment of deer activity at distinct feeding sites and could be used in studies of feeding behavior and movements of other free-ranging herbivores
Eclipsing binary and white dwarf features associated with K2 target EPIC251248385
White dwarfs, remnants of Sun-like stars which have completed their evolution, are one of the most common types of stars in space. Despite this, very few white dwarfs have been observed in transiting or eclipsing systems, and only two planetary systems around white dwarfs are currently known, thus motivating a search for white dwarfs with transits or eclipses as seen by the Kepler telescope. A systematic search of K2 white dwarf targets revealed one candidate with regular eclipses, but additional research was necessary to confirm the transits and white dwarf signal were coming from the same astrophysical source. The software package PyKe was utilized to adjust the light curve aperture, and perform principal component analysis which revealed that the transits were originating from a single pixel. Generating a new lightcurve from this pixel revealed the absolute transit depth, which was unconstrained previously. Ten additional images taken with the 2m LCOGT telescope revealed that a potential target star in the single Kepler pixel was actually a cluster of three stars, but no clear transits were seen from any of the potential target stars in the followup images. Additionally, analysis of transit depths in the single pixel light curve and additional investigation of nearby bright sources supported the hypothesis that the transits were more likely to be coming from the white dwarf rather than the two other sources. However, the transit duration and shape appear atypical for white dwarf systems. Thus, despite determining the potential sources and relative sizes for the potential eclipsing white dwarf candidate, or whether the eclipses come from the white dwarf target cannot be confirmed without additional data.https://iopscience.iop.org/article/10.3847/2515-5172/ab5861Published versio
Cosmic Shear Results from the Deep Lens Survey - II: Full Cosmological Parameter Constraints from Tomography
We present a tomographic cosmic shear study from the Deep Lens Survey (DLS),
which, providing a limiting magnitude r_{lim}~27 (5 sigma), is designed as a
pre-cursor Large Synoptic Survey Telescope (LSST) survey with an emphasis on
depth. Using five tomographic redshift bins, we study their auto- and
cross-correlations to constrain cosmological parameters. We use a
luminosity-dependent nonlinear model to account for the astrophysical
systematics originating from intrinsic alignments of galaxy shapes. We find
that the cosmological leverage of the DLS is among the highest among existing
>10 sq. deg cosmic shear surveys. Combining the DLS tomography with the 9-year
results of the Wilkinson Microwave Anisotropy Probe (WMAP9) gives
Omega_m=0.293_{-0.014}^{+0.012}, sigma_8=0.833_{-0.018}^{+0.011},
H_0=68.6_{-1.2}^{+1.4} km/s/Mpc, and Omega_b=0.0475+-0.0012 for LCDM, reducing
the uncertainties of the WMAP9-only constraints by ~50%. When we do not assume
flatness for LCDM, we obtain the curvature constraint
Omega_k=-0.010_{-0.015}^{+0.013} from the DLS+WMAP9 combination, which however
is not well constrained when WMAP9 is used alone. The dark energy equation of
state parameter w is tightly constrained when Baryonic Acoustic Oscillation
(BAO) data are added, yielding w=-1.02_{-0.09}^{+0.10} with the DLS+WMAP9+BAO
joint probe. The addition of supernova constraints further tightens the
parameter to w=-1.03+-0.03. Our joint constraints are fully consistent with the
final Planck results and also the predictions of a LCDM universe.Comment: Accepted for publication in Ap
Robust Method of Determining Microfacet BRDF Parameters in the Presence of Noise via Recursive Optimization
Accurate bidirectional reflectance distribution function (BRDF) models are essential for computer graphics and remote sensing performance. The popular microfacet class of BRDF models is geometric-optics-based and computationally inexpensive. Fitting microfacet models to scatterometry measurements is a common yet challenging requirement that can result in a model being fit as one of several unique local minima. Final model fit accuracy is therefore largely based on the quality of the initial parameter estimate. This makes for widely varying material parameter estimates and causes inconsistent performance comparisons across microfacet models, as will be shown with synthetic data. We proposed a recursive optimization method for accurate parameter determination. This method establishes an array of local minima best fits by initializing a fixed number of parameter conditions that span the parameter space. The identified solution associated with the best fit quality is extracted from the local array and stored as the relative global best fit. This method is first applied successfully to synthetic data, then it is applied to several materials and several illumination wavelengths. This method proves to reduce manual parameter adjustments, is equally weighted across incident angles, helps define parameter stability within a model, and consistently improves fit quality over the high-error local minimum best fit from lsqcurvefit by an average of 71%
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