2,771 research outputs found
The Platte as a Prairie River: A Response to Johnson and Boettcher
Johnson and Boettcher (2000) question the status of the presettlement Platte River as a prairie river, and they argue that it was a wooded river traversing a prairie landscape. Here we review evidence in support of the prairie river concept, suggesting the channels of the Platte were predominantly open and largely absent of trees. Direct support for a prairie river is found in the detailed map drawn by Lieutenant Woodbury in locating the site for Fort Kearny in 1847. Woodbury showed a thin strip of timber, located in an area that appeared to be elevated above the influence of active river flows. Woodbury also illustrated the main channel as having vegetated islands only in one location, with only a scattering [of] trees along the banks. Historical accounts, an examination of historical perspectives, the distribution of land survey witness trees, a lack of regeneration of trees following supposed deforestation, and population changes in bird distributions over the past 100 years also support the prairie river concept. We argue woodland development is not true restoration in this area. Given current conditions, we suggest that long term management should be for a mosaic of habitats for migratory birds and other species including 10% open river channel in the Big Bend reach of the Platte River in central Nebraska
Carbon Dioxide: Harmless, Ubiquitous, and Certainly Not a Pollutant Under a Liability Policy\u27s Absolute Pollution Exclusion
Boar rearing: the influence of group vs individual penning from weaning to 27 weeks of age
We compared mating performance and soundness of feet and legs of boars which were reared in group vs individual pens. Individually penned boars consumed more feed from 6 to 12 weeks of age and were heavier at 12 weeks of age. However, individually penned boars also were more unsound and tended to score lower in mating tests.; Swine Day, Manhattan, KS, November 11, 198
The effects on boar reproductive efficiency of exposure to females during rearing
Thirty-two boars (16 littermates) were reared from 3½ to 5½ months in either an all-male group or with fence-line exposure to cycling sows and gilts. Exposure to females did not significantly increase testicle or accessory gland weights, sperm production, or libido score. Boars that displayed more sexual activity (mounts and sheath sniffs) from 3½ to 5½ months of age performed superiorly in mating tests at 5½ and 7½ months of age. Libido scores of littermate boars were very similar.; Swine Day, Manhattan, KS, November 13, 198
A review of methods for detecting rats at low densities, with implications for surveillance
Invasive rats are the biggest threat to island biodiversity world-wide. Though the ecological impacts of rats on insular biota are well documented, introduced rats present a difficult problem for detection and management. In recent decades, improved approaches have allowed for island-wide eradications of invasive rats on small-medium sized islands and suppression on large islands, although both these still represent a formidable logistical and financial challenge. A key aspect of eradication or suppression and ongoing management is the ability to detect the presence of rats, especially at low densities. Here we review recent developments in the field of rat surveillance and summarise current published literature to recommend practices and the factors to consider when developing a surveillance program for either eradication or suppression plans. Of 51 empirical studies covering 17 countries, 58% were from New Zealand. Although detecting rats at low density is extremely challenging, advances over the past 15 years, have significantly improved our ability to detect rats. Motion-sensored cameras and rodent detection dogs have greatly improved our ability to detect rats at low densities, with cameras consistently showing an ability to detect rats at lower densities than other techniques. Rodent detection dogs are also able to reliably detect even an individual rat, although there are challenges to their widespread adoption, particularly in developing countries, due to the cost and skills required for their training and maintenance. New monitoring devices, the use of eDNA and drones represent current and future innovations to improve detection
Factors to Consider in Improving Prescription Drug Pharmacy Leaflets
Today, when consumers receive prescription drug pharmacy leaflets (also known as ‘consumer medication information’ or CMI), they often appear in small font size, with cluttered layouts, and distracting information. This problem has attracted the attention of the U.S. Food and Drug Administration in advocating for more comprehendible, accurate, and easy-to-access CMI formats. Our study of four different CMI prototypes shows that an expanded Over-the-Counter (OTC) Drug Facts prototype is the best for improving comprehension accuracy, and is especially effective for those with lower health literacy and health motivation. A simpler OTC prototype did not aid accuracy scores due in part to its lack of complexity; whereas the most complex prototype (the revised medication guide – similar to most CMI today) reduced leaflet likability and usage intentions. Finally, continued leaflet availability improved accuracy scores for lower health literacy and health motivation respondents. Implications for marketing and public health policy are offered
Industrial policy change in the post-crisis British economy: policy innovation in an incomplete institutional and ideational environment
Industrial policy rarely features in analysis of post-crisis economic policy change in Britain, despite manufacturing featuring centrally in the 'rebalancing' narrative espoused by elites since 2008. The article seeks to interrogate the character of recent governments' approaches to industrial policy and manufacturing industries. It does so through the prism of Peter Hall's 'three orders of policy change' framework, with particular reference to its application to macroprudential regulation by Andrew Baker. The article argues that the framework must be furnished with additional variables, namely, the type of institutional arrangements related to the policy area, and the status of the associated economic activities within the wider growth model, in order to better understand how ideas, institutions and interests interact in processes of policy change. The article finds little evidence of a 'paradigm shift' and suggests that innovations in industrial policy have served to reinforce the foundational assumptions of the British growth model
A new era of wide-field submillimetre imaging: on-sky performance of SCUBA-2
SCUBA-2 is the largest submillimetre wide-field bolometric camera ever built.
This 43 square arc-minute field-of-view instrument operates at two wavelengths
(850 and 450 microns) and has been installed on the James Clerk Maxwell
Telescope on Mauna Kea, Hawaii. SCUBA-2 has been successfully commissioned and
operational for general science since October 2011. This paper presents an
overview of the on-sky performance of the instrument during and since
commissioning in mid-2011. The on-sky noise characteristics and NEPs of the 450
and 850 micron arrays, with average yields of approximately 3400 bolometers at
each wavelength, will be shown. The observing modes of the instrument and the
on-sky calibration techniques are described. The culmination of these efforts
has resulted in a scientifically powerful mapping camera with sensitivities
that allow a square degree of sky to be mapped to 10 mJy/beam rms at 850 micron
in 2 hours and 60 mJy/beam rms at 450 micron in 5 hours in the best weather.Comment: 18 pages, 15 figures.SPIE Conference series 8452, Millimetre,
Submillimetre and Far-infrared Detectors and Instrumentation for Astronomy VI
201
Gravitational Waves from Light Cosmic Strings: Backgrounds and Bursts with Large Loops
The mean spectrum and burst statistics of gravitational waves produced by a
cosmological population of cosmic string loops are estimated using analytic
approximations, calibrated with earlier simulations. Formulas are derived
showing the dependence of observables on the string tension, in the regime
where newly-formed loops are relatively large, not very much smaller than the
horizon. Large loops form earlier, are more abundant, and generate a more
intense stochastic background and more frequent bursts than assumed in earlier
background estimates, enabling experiments to probe lighter cosmic strings of
interest to string theory. Predictions are compared with instrument noise from
current and future experiments, and with confusion noise from known
astrophysical gravitational wave sources such as stellar and massive black hole
binaries. In these large-loop models, current data from millisecond pulsar
timing already suggests that the tension is less than about , a
typical value expected in strings from brane inflation. LISA will be sensitive
to stochastic backgrounds created by strings as light as , at frequencies where it is limited by confusion noise of Galactic
stellar populations; however, for those lightest detectable strings, bursts are
rarely detectable.Comment: 22 pages, Latex, 1 figure, submitted to Phys Rev D; minor corrections
and clarifications adde
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