2,708 research outputs found
Destroy the Common Barberry Bush
Why the Common Barberry Must Be Destroyed. It harbors and propagates black stem rust of wheat and other grains. It is a patriotic duty of every one in the state who owns even one bush of the common barberry to dig it out and destroy it and thereby help save the millions of bushels of wheat which are annually destroyed by rust
Interpreting New Data on Large Scale Bulk Flows
We study the implications of a recent estimate of the bulk flow of a sample
of galaxies containing supernovae type Ia by Riess, Press, and Kirshner. We
find that their results are quite consistent with power spectra from several
currently popular models of structure formation, but that the sample is as yet
too sparse to put significant constraints on the power spectrum. We compare
this new result with that of Lauer and Postman, with which there is apparent
disagreement. We find that for the power spectra we consider, the difference in
window functions between the two samples used for the measurements results in a
low level of expected correlation between the estimated bulk flows. We
calculate a for the two measurements taken together and find that
their lack of agreement tends to disfavor spectra with excessive power on large
scales, but not at a level sufficient to rule them out. A sample consisting of
other SN type Ia's found in the Asiago catalog is used to study how the
sensitivity of the method used by RPK will improve with increasing sample size.
We conclude that the local group motion should be able to be determined with a
sample of SN Ia light curve shapes.Comment: 13 pages, 2 figures included in a self-unpacking uudecoded gzipped
postscript file. We changed some of the power spectra analyzed and expanded
the discussion. The postscript file is available at
http://pupgga.princeton.edu/disk20/anonymous/feldman/bflows.p
Date and Rate of Corn Planting
Corn is South Dakota’s most important grain crop. It is grown on 4 million acres annually. South Dakota ranks ninth among the states as a corn producer, having one-twentieth of the national acreage and one-thirtieth of the production. The state may be divided into three areas on the basis of the place of corn on the farm: the eastern area, where corn is complementary to wheat and grazing; and the western area, where corn is supplementary grazing
Optimal Moments for the Analysis of Peculiar Velocity Surveys
We present a new method for the analysis of peculiar velocity surveys which
removes contributions to velocities from small scale, nonlinear velocity modes
while retaining information about large scale motions. Our method utilizes
Karhunen--Lo\`eve methods of data compression to construct a set of moments out
of the velocities which are minimally sensitive to small scale power. The set
of moments are then used in a likelihood analysis. We develop criteria for the
selection of moments, as well as a statistic to quantify the overall
sensitivity of a set of moments to small scale power. Although we discuss our
method in the context of peculiar velocity surveys, it may also prove useful in
other situations where data filtering is required.Comment: 25 Pages, 3 figures. Submitted to Ap
A New Approach to Probing Large Scale Power with Peculiar Velocities
We propose a new strategy to probe the power spectrum on large scales using
galaxy peculiar velocities. We explore the properties of surveys that cover
only two small fields in opposing directions on the sky. Surveys of this type
have several advantages over those that attempt to cover the entire sky; in
particular, by concentrating galaxies in narrow cones these surveys are able to
achieve the density needed to measure several moments of the velocity field
with only a modest number of objects, even for surveys designed to probe scales
\gtwid 100\hmpc. We construct mock surveys with this geometry and analyze
them in terms of the three moments to which they are most sensitive. We
calculate window functions for these moments and construct a statistic
which can be used to put constraints on the power spectrum. In order to explore
the sensitivity of these surveys, we calculate the expectation values of the
moments and their associated measurement noise as a function of the survey
parameters such as density and depth and for several popular models of
structure formation. In addition, we have studied how well these kind of
surveys can distinguish between different power spectra and found that, for the
same number of objects, cone surveys are as good or better than full-sky
surveys in distinguishing between popular cosmological models. We find that a
survey with galaxy peculiar velocities with distance errors of 15% in
two cones with opening angle of could put significant
constraints on the power spectrum on scales of \hmpc, where few other
constraints exist.Comment: 15 pages, 3 figures, Some revisions and different figure. Accepted
for publication at ApJ letter
AMERICA'S CUP GRINDERS' POWER OUTPUT CAN BE IMPROVED WITH A BIOMECHANICAL TECHNIQUE INTERVENTION
Grinding provides the power behind tacking and gybing, where the yacht crosses the wind to change direction. This study evaluated the effect of a technique intervention on grinding performance. Ten America's Cup grinders were assessed, via videoed joint kinematics and grinder ergometer power output, before and after a technique intervention based on biomechanical principles. Anthropometric measures were obtained from each grinder using ISAK protocols. Maximal strength was assessed using 1 RM bench pull. The intervention produced a 4.7% increase in mean power output (p = 0.012). Regression analysis indicated predictors for grinding performance were COM. position and maximal strength
Grasses and Legumes for South Dakota
Farm operators in South Dakota are seeding considerable acreages of previously cropped land back to grasses and legumes. In recent years the state agricultural experiment stations and the United States Department of Agriculture have introduced or developed species of grasses and legumes which are superior to our native types for seed, hay and grazing purposes. A few outstanding contributions in this field of research have been the work with crested wheatgrass, Ree wheatgrass, and Ladak, Cossack and Ranger alfalfa. Grasses and legumes rank far ahead of any other crop in importance in this state. At present, more than 28,400,000 acres (Fig. 1), twice the acreage of all other crops combined, are in grasses and legumes which furnish a major portion of feed for our grazing animals. An increase in the acreage of grasses and legumes has been adopted as a national policy because forage crops not only aid in conserving the soil but contribute to a better balanced agriculture
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