2,091 research outputs found
A Further Empirical Investigation into “Up To” Advertising Claims: The “As Low As” Claim
For many years the Federal Trade Commission has sought to prevent deceptive advertising under Section 5 of the Federal Trade Commission Act. The FTC’s focus has encompassed not only false advertising claims, but also advertising claims that, while literally true, tend to deceive consumers. “Up to” claims fall under this scrutiny since they can be misunderstood as promising consumer benefits (e.g. “up to 50% savings”) that might not be realized by all consumers. This paper presents the results of research conducted with 600+ members of a commercial consumer panel to evaluate a variant of this type of claim, the “As Low As” claim, and to extend prior research by examining how interpretation of the claim varies with audience characteristics. Implications for advertising practitioners are discussed
Supplementing fructose-based block supplements to forage-fed cattle increases capacity for lactic acid metabolism
Acidosis is one of the more important maladies afflicting cattle fed significant amounts
of grain and has enormous economic impact for feedlots, dairies, and producers of
seed stock. The highest incidence of acidosis occurs when animals are being transitioned
from high-roughage diets to diets containing high levels of concentrates. When
grain-based diets are consumed in excess, consumed too quickly, or fed without proper
adaptation, digestive end products (organic acids) can accumulate within the rumen,
resulting in acidosis. Lactic acid is one of the key organic compounds that accumulates
under these conditions. Coupled with the animal’s limited ability to metabolize lactate,
accumulation of lactic acid in the rumen lowers ruminal pH and subsequently depresses
feed intake. One means of preventing acidosis is to directly populate the rumen with
lactate-utilizing bacteria. Alternatively, exposure to low levels of lactate (i.e., levels insufficient
to harm the animal) may stimulate development of a population of lactate-utilizing
bacteria. The objective of our study was to determine if supplementing low-moisture
blocks made of high fructose corn syrup could increase ruminal lactate concentrations
and subsequently stimulate growth of lactate-metabolizing bacteria. If successful, this
could prove useful for adapting forage-fed cattle to grain-based diets
MaGICC-WDM: the effects of warm dark matter in hydrodynamical simulations of disc galaxy formation
We study the effect of warm dark matter (WDM) on hydrodynamic simulations of
galaxy formation as part of the Making Galaxies in a Cosmological Context
(MaGICC) project. We simulate three different galaxies using three WDM
candidates of 1, 2 and 5 keV and compare results with pure cold dark matter
simulations. WDM slightly reduces star formation and produces less centrally
concentrated stellar profiles. These effects are most evident for the 1 keV
candidate but almost disappear for keV. All simulations
form similar stellar discs independent of WDM particle mass. In particular, the
disc scale length does not change when WDM is considered. The reduced amount of
star formation in the case of 1 keV particles is due to the effects of WDM on
merging satellites which are on average less concentrated and less gas rich.
The altered satellites cause a reduced starburst during mergers because they
trigger weaker disc instabilities in the main galaxy. Nevertheless we show that
disc galaxy evolution is much more sensitive to stellar feedback than it is to
WDM candidate mass. Overall we find that WDM, especially when restricted to
current observational constraints ( keV), has a minor
impact on disc galaxy formation.Comment: 13 pages, 9 figures, 2 tables; minor clarifications added in results
section, conclusions unchanged; accepted for publication in MNRA
Final Summary Report to the Narragansett Bay Project Office: Assessment of Organic Contaminants in Narragansett Bay Sediments and Hard Shell Clams
As part of a multidisciplinary investigation on the sediments of Narragansett Bay, sediment trap materials, surface sediments, hard shell clams (Mercenaria mercenaria) and sediment cores from throughout the bay were analyzed for organic contaminants including: polychlorinated biphenyls (PCBs), petroleum hydrocarbons (PHCs). polycyclic aromatic hydrocarbons (PAHs), substituted benzotriazoles (BZTs), bis (2-ethylhexyl) phthalate (DEHP) and coprostanol (COP). The objectives of this particular study were to provide information on the source, transport and biogeochemical fate of organic contaminants in the bay: while the overall goals of the investigation were to characterize the sediments and sedimentary processes of the Narragansett Bay system based on the results of integrated biological, chemical and geological studies.
Sediment Trap Materials
The sediment trap samples showed a trend of decreasing concentration for most components from Fox Point to Ohio Ledge, suggesting that the source(s) of these contaminants were pollution discharges (e.g., industrial and municipal effluents, CSOs. spills and runoff,) to the upper Providence River and its tributaries. In general, the agreement between the results from the present sediment trap study and older suspended solids data (1985-86) was quite good. However, the PHC concentrations reponed in 1977 were considerably higher than the more recent values. But it is difficult, if not impossible, to determine if changes have really occurred based on the limited number of samples analyzed and procedural variations in the different studies.
In the case of BZT concentrations and their ratios (C10-BZT/Cl-BZT), there was a maximum amount of both BZTs and a minimum ratio in trap material at a Providence River station about 7 km south of Fox Point (i.e., adjacent to the Pawtuxet Cove entrance). This trend with distance is probably due to the source of the BZTs to the Providence River which is the Pawtuxet River via Pawtuxet Cove. The BZT ratio indicates a change in the relative amounts of the two compounds over the distance from the point of entry, i.e., there is a trend of increasing values with distance from Pawtuxet Cove (ratio = 1.5) to Ohio Ledge (ratio = 3.2). The ratio for sediment trap material from the Pawtuxet River was 1.0 - 2.0; since these values are generally lower than any others reported, it suggests that the river is the major source of the material in the Pawtuxet Cove traps.
The relationships between contaminant concentrations in sediment trap material and surface sediments were quite good. For Ar 1254, the sediment levels were about twice the trap values. Conversely, the hydrocarbon concentrations in trap material were about 1.5 times as high for PHCs and about equal in pyrene, relative to the surface sediments. (In all cases, the correlations were significant at the 95% confidence level). In general, these data support the concept that the chemical composition of particulate material and surf ace sediments are closely related, and that the former could be a major source of contaminants to the underlying surface sediments. It is also possible that resuspended surface sediments could contribute to the particulate material in the water column depending on a number of factors such as bottom currents and extent of bioturbation.
There was a significant relationship between the concentration of Cl-BZT in trap material and surface sediments; however, the relationship for the C10-BZT was not as good. and there is presently no explanation for these differences other than that the production of C-BZT started in 1963 and ceased in 1972, while that of the C10-BZT started in 1970 and continued to 1985. (The log Kow for both BZTs are essentially the same, Pruell & Quinn, 1985.) Perhaps, the former BZTs more uniformally distributed in particulate material and sediments than the more recently discharged C10-BZT. Changes in the BZT ratio (C10/Cl) of trap material may be due to a number of reasons including: the preferential retention of the C10-BZT and/or loss of Cl-BZT due to various biogeochemical reactions, and the resuspension of more recent sediments containing higher concentrations of the C10-BZT. This trend would be in agreement with the low ratio in Pawtuxet River surface sediments relative to sediment from the other locations where the ratios generally increase as found in the trap material. For example, the BZT ratio in surface sediments from Ohio Ledge is 7.2, in the mid-bay it is 8.2 and at the west passage the ratio is 9.5 (significant at the 9S% confidence level).
Surface Sediments and Clams
In general, the levels of all contaminants were highest in the Providence River sediments and decreased exponentially with distance downbay, with the lowest values usually found at the mouth of the bay. The major exception was a station in Newport Harbor in the lower east passage, where the concentrations of PHCs, PCBs and COP were relatively high and similar to some of the upper bay stations. The sources of the contaminants at this station may be related to sewage effluent, CSO discharges and runnoff to the harbor area.
One way of evaluating the distribution of various contaminants in surface sediments is to compare the half distances for these components (defined as the distance in which the highest contaminant concentration decreases by 50%). A comparison of values for the east and west transects obtained in this study showed some small differences. For most components (exceptions are BZTs) the half distances were longer in the cast transect, suggesting additional sources of contaminants to that area. This may be due to several reasons including the influence of Newport effluents etc., different water circulation patterns in the two passages, and possible influences from Mount Hope Bay. Organic carbon had the longest half distance due to a large number of sources throughout the bay, and the BZTs had the lowest values since their only source is the Providence River via the Pawtuxct River. Finally, the PH Cs, P AHs. PCBs (sometimes measured as specific chlorobiphenyl (CB) cogeners) and coprostanol had similar half distances, suggesting major sources in the Providence River as well as smaller additional inputs throughout the bay.
Five of the contaminants (CB 101, CB 138, PHCs, C10-BZT) showed significant correlations (95% confidence level or better) between sediment and clam concentrations, and all values decreased with distance from the Providence River. These sediment components are hydrophobic and are strongly partitioned into the clams\u27 lipids. Based on the data from this study, it may be possible to identify areas of the bay from which clams are harvested for commercial use. For example, clams suspected of being taken from areas closed to shellfishing could be analyzed for, these 5 contaminants and the results converted to sediment location using the relationships developed in this investigation.
Trends from older investigations were generally similar to those observed in the present study; namely, highest concentrations in Providence River sediments and clams with decreasing amounts downbay. The range of previous values brackets those obtained in this study. Given then variations in station location, collection procedures, processing techniques and analytical methods, it is impossible to determine at the present time, if the concentrations have significantly changed over the past 15-20 years.
Sediment Cores
Highest levels and deepest penetration of PCBs (measured as CB 138) were in the Fox Point core which had a fairly uniform concentration down to 72 cm, but increased at 110 cm and remained about the same at the bottom of the core (147 cm). The other cores showed less penetration ranging from 42 cm (bottom of core) at Conimicut Point to 13 cm at Fields Point where the CB 138 values reached background (\u3c 0.1 ng/g) concentration. Apparently, the latter core site is a non-depositional area in contrast to Fox Point which has a relatively high sedimentation rate.
The distribution of PHCs and pyrene were similar in some respects. In both cases, Fox Point had the highest level and deepest penetration with relatively constant values down to 147 cm. The PHCs never quite reached background levels in these cores (Ohio Ledge and Fields Point were the closest to background), but the pyrene did reach this level in two cores including the Fields Point core which again had the shallowest penetration (18 cm).
Similar distributions were shown by COP and DEHP in that the Fox Point core had the highest levels and deepest penetration - a slight increase down to 110 cm followed by a prominent decrease to 147 cm. None of the cores reached background values for DEHP, but Ohio Ledge and Conimicut Point came very close. The COP reached background in only the Fields Point core but it rapidly increased again.
It is impossible to adequately explain all of the trends in sediment core distributions with only the organic contaminant results. However, a detailed evaluation of all of the data (i.e., trace metals, organic components, biological species, pollen and geochemical analyses and radiometric dating) is currently being prepared in order to provide information on historical trends as recorded in the bay sediment cores (King et al., 1992).
[Text taken from report summary.
The H alpha Galaxy Survey VI. Star-forming companions of nearby field galaxies
We present a search for star-forming satellite galaxies that are close enough
to their parent galaxies to be considered analogues of the Magellanic Clouds.
Our search technique relied on the detection of the satellites in
continuum-subtracted narrow-band H alpha imaging of the central galaxies, which
removes most of the background and foreground line-of-sight companions, thus
giving a high probability that we are detecting true satellites. The search was
performed for 119 central galaxies at distances between 20 and 40 Mpc, although
spatial incompleteness means that we have effectively searched 53 full
satellite-containing volumes. We find only 9 probable star-forming satellites,
around 9 different central galaxies, and 2 possible satellites. After
incompleteness correction, this is equivalent to 0.17/0.21 satellites per
central galaxy. The Small Magellanic Cloud is just below the median values of
both star formation rate and R-band luminosity of the 9 probable satellites.
The Large Magellanic Cloud, however, has a higher R-band luminosity than any of
the 9 and is only exceeded in star formation rate by the one satellite that
appears to be undergoing a tidally-induced starburst. Thus the Milky Way
appears to be quite unusual, both in having two star-forming satellite galaxies
and in the high luminosity of the Large Magellanic Cloud.Comment: 13 pages, accepted for publication in A&
Degermed corn distiller’s grains with solubles (DGS) have feed value similar to traditional distiller’s grains
Rapid expansion of the fuel ethanol industry has greatly increased availability of distillery byproducts. Distiller\u27s grains with solubles (DGS) are the predominant byproduct of fermenting grains into fuel ethanol. During this process, starch is removed from the grain and the residual components of the grain are concentrated in the DGS. Improvements in the conversion of cereal grains to ethanol have been fueled by recent changes in the production process. Broin Companies (Sioux Falls, SD) have developed a technology that removes the germ before the fermentation process. The resulting byproduct contains more protein, less crude fat, and less phosphorus compared to traditional distiller\u27s grains. Feeding even modest levels of DGS can contribute to greater phosphorus excretion from feedlots, suggesting that strategies aimed at reducing phosphorus levels are well warranted. The objective of this study was to compare diets based on steam-flaked corn with and without DGS and to compare a highprotein, low-fat, low-phosphorus byproduct to more traditional distiller\u27s grains
The effects of ractopamine-HCl (optaflexx) on performance, carcass characteristics, and meat quality of finishing feedlot heifers
Beta-adrenergic agonists are commonly used in livestock production to accelerate growth by enhancing lean tissue gain. These compounds repartition nutrients away from fat deposition and toward protein accretion. Generally, increased growth is associated with ractopamine feeding, which improves feed conversion and increases body weight gain. However, little data exists on the effects of ractopamine-HCl on live performance or carcass characteristics of beef heifers. Data released from Elanco Animal Health indicate that differences between gender may exist in response to ractopamine, and therefore appropriate strategies for the administration of this compound must be defined for heifers independent of those for steers. The objective of this study was to determine the effects of Optaflexx, when fed for different dosages over different durations, on finishing heifer performance
Reionization and the abundance of galactic satellites
One of the main challenges facing standard hierarchical structure formation
models is that the predicted abundance of galactic subhalos with circular
velocities of 10-30 km/s is an order of magnitude higher than the number of
satellites actually observed within the Local Group. Using a simple model for
the formation and evolution of dark halos, based on the extended
Press-Schechter formalism and tested against N-body results, we show that the
theoretical predictions can be reconciled with observations if gas accretion in
low-mass halos is suppressed after the epoch of reionization. In this picture,
the observed dwarf satellites correspond to the small fraction of halos that
accreted substantial amounts of gas before reionization. The photoionization
mechanism naturally explains why the discrepancy between predicted halos and
observed satellites sets in at about 30 km/s, and for reasonable choices of the
reionization redshift (z_re = 5-12) the model can reproduce both the amplitude
and shape of the observed velocity function of galactic satellites. If this
explanation is correct, then typical bright galaxy halos contain many low-mass
dark matter subhalos. These might be detectable through their gravitational
lensing effects, through their influence on stellar disks, or as dwarf
satellites with very high mass-to-light ratios. This model also predicts a
diffuse stellar component produced by large numbers of tidally disrupted
dwarfs, perhaps sufficient to account for most of the Milky Way's stellar halo.Comment: 5 pages, 2 figures, Submitted to Ap
Halo Substructure and the Power Spectrum
In this proceeding, we present the results of a semi-analytic study of CDM
substructure as a function of the primordial power spectrum. We apply our
method to several tilted models in the LCDM framework with n=0.85-1.1,
sigma_8=0.65-1.2 when COBE normalized. We also study a more extreme, warm dark
matter-like spectrum that is sharply truncated below a scale of 10^10 h^-1
Msun. We show that the mass fraction of halo substructure is not a strong
function of spectral slope, so it likely will be difficult to constrain tilt
using flux ratios of gravitationally lensed quasars. On the positive side, all
of our CDM-type models yield projected mass fractions in good agreement with
strong lensing estimates: f \sim 1.5% at M \sim 10^8 Msun. The truncated model
produces a significantly smaller fraction, f \lsim 0.3%, suggesting that warm
dark matter-like spectra may be distinguished from CDM spectra using lensing.
We also discuss the issue of dwarf satellite abundances, with emphasis on the
cosmological dependence of the map between the observed central velocity
dispersion of Milky Way satellites and the maximum circular velocities of their
host halos. In agreement with earlier work, we find that standard LCDM
over-predicts the estimated count of Milky Way satellites at fixed Vmax by an
order of magnitude, but tilted models do better because subhalos are less
concentrated. Interestingly, under the assumption that dwarfs have isotropic
velocity dispersion tensors, models with significantly tilted spectra (n \lsim
0.85, sigma_8 \lsim 0.7) may under-predict the number of large Milky Way
satellites with Vmax \gsim 40 km/s.Comment: 5 pages, 2 figures. Poster contribution to the 13th Annual
Astrophysics Conference in Maryland, The Emergence of Cosmic Structur
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