37,064 research outputs found
WHEN THE !%$? HITS THE LAND: IMPLICATIONS FOR US AGRICULTURE AND ENVIRONMENT WHEN LAND APPLICATION OF MANURE IS CONSTRAINED
Confined animal production in the U.S. and its associated discharge of manure nutrients into area waters is considered a leading contributor to current water quality impairments. A common option to mitigate these impairments is to limit land application of manure. This paper evaluates the implications of alternative land application constraints for U.S. agriculture and the environment at the regional and sector level. The results suggest that when these constraints are particularly binding, due to minimal acceptance of manure as a substitute for commercial fertilizer, potentially large and unanticipated changes in returns to agricultural production and water quality may occur. Furthermore, we find that some of the cost of meeting the land application constraints will be passed on to consumers through higher prices and to a portion of rural economies through lower production rates and labor expenditures.Environmental Economics and Policy, Livestock Production/Industries,
A Carrot-and-Stick Approach to Environmental Improvement: Marrying Agri-Environmental Payments and Water Quality Regulations
Agri-environmental programs, such as the Environmental Quality Incentives Program, provide payments to livestock and crop producers to generate broadly defined environmental benefits and to help them comply with federal water quality regulations, such as those that require manure nutrients generated on large animal feeding operations to be spread on cropland at no greater than agronomic rates. We couch these policy options in terms of agri-environmental "carrots" and regulatory "sticks," respectively. The U.S. agricultural sector is likely to respond to these policies in a variety of ways. Simulation analysis suggests that meeting nutrient standards would result in decreased levels of animal production, increased prices for livestock and poultry products, increased levels of crop production, and water quality improvements. However, estimated impacts are not homogeneous across regions. In regions with relatively less cropland per ton of manure produced, the impacts of these policies are more pronounced.Environmental Economics and Policy,
On Extended Electroweak Symmetries
We discuss extensions of the Standard Model through extending the electroweak
gauge symmetry. An extended electroweak symmetry requires a list of extra
fermionic and scalar states. The former is necessary to maintain cancellation
of gauge anomalies, and largely fixed by the symmetry embedding itself. The
latter is usually considered quite arbitrary, so long as a vacuum structure
admitting the symmetry breaking is allowed. Anomaly cancellation may be used to
link the three families of quarks and leptons together, given a perspective on
flavor physics. It is illustrated lately that the kind of models may also have
the so-called little Higgs mechanism incorporated. This more or less fixes the
scalar sector and take care of the hierarchy problem, making such models of
extended electroweak symmetries quite appealing candidates as TeV scale
effective field theories.Comment: 1+8 pages of latex with ws-procs9x6.cls; talk presented at Coral
Gables Conference 200
CP Violation from a Higher Dimensional Model
It is shown that Randall-Sundrum model has the EDM term which violates the
CP-symmetry. The comparison with the case of Kaluza-Klein theory is done. The
chiral property, localization, anomaly phenomena are examined. We evaluate the
bulk quantum effect using the method of the induced effective action. This is a
new origin of the CP-violation.Comment: 15pages, Proc. of Int. Workshop on "Neutrino Masses and
Mixings"(Dec.17-19,2006,Univ.of Shizuoka,Japan
Inequalities for low-energy symmetric nuclear matter
Using effective field theory we prove inequalities for the correlations of
two-nucleon operators in low-energy symmetric nuclear matter. For physical
values of operator coefficients in the effective Lagrangian, the S = 1, I = 0
channel correlations must have the lowest energy and longest correlation length
in the two-nucleon sector. This result is valid at nonzero density and
temperature.Comment: 9 page
A New Experiment to Study Hyperon CP Violation and the Charmonium System
Fermilab operates the world's most intense antiproton source, now exclusively
dedicated to serving the needs of the Tevatron Collider. The anticipated 2009
shutdown of the Tevatron presents the opportunity for a world-leading low- and
medium-energy antiproton program. We summarize the status of the Fermilab
antiproton facility and review physics topics for which a future experiment
could make the world's best measurements.Comment: 16 pages, 3 figures, to appear in Proceedings of CTP symposium on
Supersymmetry at LHC: Theoretical and Experimental Perspectives, The British
University in Egypt, Cairo, Egypt, 11-14 March 200
The Delta-Delta Intermediate State in 1S0 Nucleon-Nucleon Scattering From Effective Field Theory
We examine the role of the Delta-Delta intermediate state in low energy NN
scattering using effective field theory. Theories both with and without pions
are discussed. They are regulated with dimensional regularization and MSbar
subtraction. We find that the leading effects of the Delta-Delta state can be
absorbed by a redefinition of the contact terms in a theory with nucleons only.
It does not remove the requirement of a higher dimension operator to reproduce
data out to moderate momentum. The explicit decoupling of the Delta-Delta state
is shown for the theory without pions.Comment: 16 pages, 3 figures, uses harvma
Little Higgs Model Completed with a Chiral Fermionic Sector
The implementation of the little Higgs mechanism to solve the hierarchy
problem provides an interesting guiding principle to build particle physics
models beyond the electroweak scale. Most model building works, however, pay
not much attention to the fermionic sector. Through a case example, we
illustrate how a complete and consistent fermionic sector of the TeV effective
field theory may actually be largely dictated by the gauge structure of the
model. The completed fermionic sector has specific flavor physics structure,
and many phenomenological constraints on the model can thus be obtained beyond
gauge, Higgs, and top physics. We take a first look on some of the quark sector
constraints.Comment: 14 revtex pages with no figure, largely a re-written version of
hep-ph/0307250 with elaboration on flavor sector FCNC constraints; accepted
for publication in Phys.Rev.
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