134 research outputs found
Evaluating Short Term and Long Term Retention of Experiences Associated with an Interpretive School Field Trip
The strong evidence that an interpretive experience can promote initial knowledge retention sets up a more difficult question: how long do these students hold on to . this information? More precisely, what do the students remember one month or more after the initial treatment? Are these memories associated with interpreter-derived program objectives or tertiary variables such as social or environmental factors? Can the memories from this experience impact a student\u27s attitude toward the resource site? These are questions that are looked at through this pilot study evaluating short term and long term retention of experiences associated with an interpretive school field trip
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Individual Value-Driven Rent Dissipation in Limited-Entry Fisheries: Experimental Evidence
Economists have devoted considerable attention to rent-dissipation in limited-entry fisheries as a result of excessive use of capital inputs, or "capital stuffing." We may refer to this mechanism of rent dissipation as "cost-driven rent dissipation." An alternative potential mechanism of rent dissipation, which we refer to as "value-driven rent dissipation," may occur if limited-entry management causes fishermen to receive a lower price for their fish than would be possible under an alternative management system. In theory, value-driven rent dissipation may occur if the marginal value to a fisherman from fishing differently (for example, more slowly to take better care of the fish and improve quality) is positive but less than the marginal cost from a reduced catch share. This paper describes an economic experiment to study value-driven rent dissipation in a limited entry fishery. Following an approach developed by Knapp and Murphy (2010), subjects "fish" competitively for beans by scooping them out of a large bowl and "delivering" them to a pitcher. Given the choice of delivering to a pitcher placed close by for a lower price or a pitcher placed farther away for a higher price, unless the price differential is sufficiently high, subjects choose the closer but lower-priced pitcher. With the introduction of an individual quota to replace the competitive fishery, value dissipation ends as subjects choose the higher-priced pitcher. This simple experiment provides a powerful demonstration of a less-appreciated mechanism of rent dissipation, which is useful for both research and teaching.Keywords: Fisheries Economics, Fish and Aquaculture Sectors Development, Contributions of Fisheries to Socioeconomic Wellbein
Understanding the Astrophysics of Galaxy Evolution: the role of spectroscopic surveys in the next decade
Over the last decade optical spectroscopic surveys have characterized the low
redshift galaxy population and uncovered populations of star-forming galaxies
back to z ~ 7. This work has shown that the primary epoch of galaxy building
and black hole growth occurs at redshifts of 2 to 3. The establishment of the
concordance LCDM cosmology shifted the focus of galaxy population studies from
constraining cosmological parameters to characterizing the processes which
regulate the formation and evolution of galaxies.In the next decade, high
redshift observers will attempt to formulate a coherent evolutionary picture
connecting galaxies in the high redshift Universe to galaxies today. In order
to link galaxy populations at different redshifts, we must not only
characterize their evolution in a systematic way, we must establish which
physical processes are responsible for it. Considerable progress has already
been made in understanding how galaxies evolved from z ~ 1 to the present day.
Large spectroscopic surveys in the near infrared are required to push these
studies back towards the main epoch of galaxy building. Only then will we
understand the full story of the formation of L* galaxies like our own Milky
Way. A large near-IR spectroscopic survey will also provide the calibration
needed to avoid systematics in the large photometric programs proposed to study
the nature of dark matter and dark energy. We provide an outline design for a
multi-object 0.4 to 1.8 micron spectrograph, which could be placed on an
existing telescope, and which would allow a full characterization of the galaxy
population out to z ~ 2. We strongly recommend a serious further study to
design a real instrument, which will be required for galaxy formation studies
to advance to the next frontier.Comment: White paper, primary author J.E. Gunn, submitted to Astro2010 Decadal
Survey, see http://www7.nationalacademies.org/bpa/Astro2010_SWP_byTitle.htm
Semi-infinite cohomology of W-algebras
We generalize some of the standard homological techniques to \cW-algebras,
and compute the semi-infinite cohomology of the \cW_3 algebra on a variety of
modules. These computations provide physical states in \cW_3 gravity coupled
to \cW_3 minimal models and to two free scalar fields.Comment: 15 page
From Too Much to Too Little: How the central U.S. drought of 2012 evolved out of one of the most devastating floods on record in 2011
Table of Contents
Section 1: Introduction....................................................................... 1
Section 2: Regional Drought Perspective................................. 2
Section 3: State Drought Perspectives........................................ 3
Section 3.1: Colorado........................................................................... 20
Section 3.2: Illinois.................................................................. 25
Section 3.3: Indiana................................................. 29
Section 3.4: Iowa...................... 36
Section 3.5: Kansas............................................................... 42
Section 3.6: Kentucky............................................................................ 46
Section 3.7: Michigan.............................. 52
Section 3.8: Minnesota............................................................ 58
Section 3.9: Missouri..................................................... 63
Section 3.10: Nebraska................................................. 67
Section 3.11: North Dakota............................................ 73
Section 3.12: Ohio................................................... 79
Section 3.13: South Dakota..................................... 85
Section 3.14: Wyoming........................................... 96
Section 4: Conclusions.............................................................. 9
The Sloan Digital Sky Survey Quasar Catalog IV. Fifth Data Release
We present the fourth edition of the Sloan Digital Sky Survey (SDSS) Quasar
Catalog. The catalog contains 77,429 objects; this is an increase of over
30,000 entries since the previous edition. The catalog consists of the objects
in the SDSS Fifth Data Release that have luminosities larger than M_i = -22.0
(in a cosmology with H_0 = 70 km/s/Mpc, Omega_M = 0.3, and Omega_Lambda = 0.7)
have at least one emission line with FWHM larger than 1000 km/s, or have
interesting/complex absorption features, are fainter than i=15.0, and have
highly reliable redshifts. The area covered by the catalog is 5740 sq. deg. The
quasar redshifts range from 0.08 to 5.41, with a median value of 1.48; the
catalog includes 891 quasars at redshifts greater than four, of which 36 are at
redshifts greater than five. Approximately half of the catalog quasars have i <
19; nearly all have i < 21. For each object the catalog presents positions
accurate to better than 0.2 arcsec. rms per coordinate, five-band (ugriz)
CCD-based photometry with typical accuracy of 0.03 mag, and information on the
morphology and selection method. The catalog also contains basic radio,
near-infrared, and X-ray emission properties of the quasars, when available,
from other large-area surveys. The calibrated digital spectra cover the
wavelength region 3800--9200A at a spectral resolution of ~2000. The spectra
can be retrieved from the public database using the information provided in the
catalog. The average SDSS colors of quasars as a function of redshift, derived
from the catalog entries, are presented in tabular form. Approximately 96% of
the objects in the catalog were discovered by the SDSS.Comment: 37 pages, Accepted for publication in A
The Sloan Digital Sky Survey Quasar Catalog V. Seventh Data Release
We present the fifth edition of the Sloan Digital Sky Survey (SDSS) Quasar
Catalog, which is based upon the SDSS Seventh Data Release. The catalog, which
contains 105,783 spectroscopically confirmed quasars, represents the conclusion
of the SDSS-I and SDSS-II quasar survey. The catalog consists of the SDSS
objects that have luminosities larger than M_i = -22.0 (in a cosmology with H_0
= 70 km/s/Mpc Omega_M = 0.3, and Omega_Lambda = 0.7) have at least one emission
line with FWHM larger than 1000 km/s or have interesting/complex absorption
features, are fainter than i > 15.0 and have highly reliable redshifts. The
catalog covers an area of 9380 deg^2. The quasar redshifts range from 0.065 to
5.46, with a median value of 1.49; the catalog includes 1248 quasars at
redshifts greater than four, of which 56 are at redshifts greater than five.
The catalog contains 9210 quasars with i < 18; slightly over half of the
entries have i< 19. For each object the catalog presents positions accurate to
better than 0.1" rms per coordinate, five-band (ugriz) CCD-based photometry
with typical accuracy of 0.03 mag, and information on the morphology and
selection method. The catalog also contains radio, near-infrared, and X-ray
emission properties of the quasars, when available, from other large-area
surveys. The calibrated digital spectra cover the wavelength region 3800-9200
Ang. at a spectral resolution R = 2000 the spectra can be retrieved from the
SDSS public database using the information provided in the catalog. Over 96% of
the objects in the catalog were discovered by the SDSS. We also include a
supplemental list of an additional 207 quasars with SDSS spectra whose archive
photometric information is incomplete.Comment: Accepted, to appear in AJ, 7 figures, electronic version of Table 2
is available, see
http://www.sdss.org/dr7/products/value_added/qsocat_dr7.htm
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Development of an In Situ Biosurfactant Production Technology for Enhanced Oil Recovery
The long-term economic potential for enhanced oil recovery (EOR) is large with more than 300 billion barrels of oil remaining in domestic reservoirs after conventional technologies reach their economic limit. Actual EOR production in the United States has never been very large, less than 10% of the total U. S. production even though a number of economic incentives have been used to stimulate the development and application of EOR processes. The U.S. DOE Reservoir Data Base contains more than 600 reservoirs with over 12 billion barrels of unrecoverable oil that are potential targets for microbially enhanced oil recovery (MEOR). If MEOR could be successfully applied to reduce the residual oil saturation by 10% in a quarter of these reservoirs, more than 300 million barrels of oil could be added to the U.S. oil reserve. This would stimulate oil production from domestic reservoirs and reduce our nation's dependence on foreign imports. Laboratory studies have shown that detergent-like molecules called biosurfactants, which are produced by microorganisms, are very effective in mobilizing entrapped oil from model test systems. The biosurfactants are effective at very low concentrations. Given the promising laboratory results, it is important to determine the efficacy of using biosurfactants in actual field applications. The goal of this project is to move biosurfactant-mediated oil recovery from laboratory investigations to actual field applications. In order to meet this goal, several important questions must be answered. First, it is critical to know whether biosurfactant-producing microbes are present in oil formations. If they are present, then it will be important to know whether a nutrient regime can be devised to stimulate their growth and activity in the reservoir. If biosurfactant producers are not present, then a suitable strain must be obtained that can be injected into oil reservoirs. We were successful in answering all three questions. The specific objectives of the project were (1) to determine the prevalence of biosurfactant producers in oil reservoirs, and (2) to develop a nutrient regime that would stimulate biosurfactant production in the oil reservoir
The Tomato Sequencing Project, the First Cornerstone of the International Solanaceae Project (SOL)
The genome of tomato (Solanum lycopersicum) is being sequenced by an international
consortium of 10 countries (Korea, China, the United Kingdom, India, The
Netherlands, France, Japan, Spain, Italy and the United States) as part of a larger initiative
called the ‘International Solanaceae Genome Project (SOL): Systems Approach
to Diversity and Adaptation’. The goal of this grassroots initiative, launched in
November 2003, is to establish a network of information, resources and scientists
to ultimately tackle two of the most significant questions in plant biology and agriculture:
(1) How can a common set of genes/proteins give rise to a wide range of
morphologically and ecologically distinct organisms that occupy our planet? (2) How
can a deeper understanding of the genetic basis of plant diversity be harnessed to
better meet the needs of society in an environmentally friendly and sustainable manner?
The Solanaceae and closely related species such as coffee, which are included
in the scope of the SOL project, are ideally suited to address both of these questions.
The first step of the SOL project is to use an ordered BAC approach to generate a
high quality sequence for the euchromatic portions of the tomato as a reference for
the Solanaceae. Due to the high level of macro and micro-synteny in the Solanaceae
the BAC-by-BAC tomato sequence will form the framework for shotgun sequencing
of other species. The starting point for sequencing the genome is BACs anchored
to the genetic map by overgo hybridization and AFLP technology. The overgos are
derived from approximately 1500 markers from the tomato high density F2-2000
genetic map (http://sgn.cornell.edu/). These seed BACs will be used as anchors from
which to radiate the tiling path using BAC end sequence data. Annotation will be
performed according to SOL project guidelines. All the information generated under
the SOL umbrella will be made available in a comprehensive website. The information
will be interlinked with the ultimate goal that the comparative biology of the
Solanaceae—and beyond—achieves a context that will facilitate a systems biology
approach
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