2,164 research outputs found
A MARKETING-SYSTEM APPROACH TO REMOVING DISTRIBUTION BARRIERS CONFRONTING SMALL-VOLUME FRUIT AND VEGETABLE GROWERS
Marketing,
State Department of Agriculture Participation in Fresh Produce Marketing in Georgia, Kentucky, North Carolina, and Tennessee
Agricultural and Food Policy,
Removing Distribution Barriers Confronting Small-Volume Fruit and Vegetable Growers: Results of the Tennessee Extension Service Survey
Crop Production/Industries, Teaching/Communication/Extension/Profession,
The Quantity Theory of Money is Valid. The New Keynesians are Wrong!
We test the quantity theory of money (QTM) using a novel approach and a large new sample. We do not follow the usual approach of first differentiating the logarithm of the Cambridge equation to obtain an equation relating the growth rate of real GDP, the growth rate of money and inflation. These variables must then again be ‘integrated’ by averaging in order to obtain stable relationships. Instead we suggest a much simpler procedure for testing directly the stability of the coefficient of the Cambridge equation. For 125 countries and post-war data we find the coefficient to be surprisingly stable. We do not select for high inflation episodes as was done in most empirical studies; inflation rates do not even appear in our data set.
Much work supporting the QTM has been done by economic historians and at the University of Chicago by Milton Friedman and his associates. The QTM was a foundation stone of the monetarist revolution. Subsequently belief in it waned. The currently dominant New Keynesian School, implicitly or explicitly denies the validity of the QTM. We survey this history and argue that the QTM is valid and New Keynesians are wrong
Spitzer observations of HH54 and HH7-11: mapping the H2 ortho-to-para ratio in shocked molecular gas
We report the results of spectroscopic mapping observations carried out
toward the Herbig-Haro objects HH7-11 and HH54 over the 5.2 - 37 micron region
using the Infrared Spectrograph of the Spitzer Space Telescope. These
observations have led to the detection and mapping of the S(0) - S(7) pure
rotational lines of molecular hydrogen, together with emissions in fine
structure transitions of Ne+, Si+, S, and Fe+. The H2 rotational emissions
indicate the presence of warm gas with a mixture of temperatures in the range
400 - 1200 K, consistent with the expected temperature behind nondissociative
shocks of velocity ~ 10 - 20 km/s, while the fine structure emissions originate
in faster shocks of velocity 35 - 90 km/s that are dissociative and ionizing.
Maps of the H2 line ratios reveal little spatial variation in the typical
admixture of gas temperatures in the mapped regions, but show that the H2
ortho-to-para ratio is quite variable, typically falling substantially below
the equilibrium value of 3 attained at the measured gas temperatures. The
non-equilibrium ortho-to-para ratios are characteristic of temperatures as low
as ~ 50 K, and are a remnant of an earlier epoch, before the gas temperature
was elevated by the passage of a shock. Correlations between the gas
temperature and H2 ortho-to-para ratio show that ortho-to-para ratios < 0.8 are
attained only at gas temperatures below ~ 900 K; this behavior is consistent
with theoretical models in which the conversion of para- to ortho-H2 behind the
shock is driven by reactive collisions with atomic hydrogen, a process which
possesses a substantial activation energy barrier (E_A/k ~ 4000 K) and is
therefore very inefficient at low temperature.Comment: 45 pages, including 16 figures. Accepted for publication in Ap
Planetary Candidates Observed by Kepler IV: Planet Sample From Q1-Q8 (22 Months)
We provide updates to the Kepler planet candidate sample based upon nearly
two years of high-precision photometry (i.e., Q1-Q8). From an initial list of
nearly 13,400 Threshold Crossing Events (TCEs), 480 new host stars are
identified from their flux time series as consistent with hosting transiting
planets. Potential transit signals are subjected to further analysis using the
pixel-level data, which allows background eclipsing binaries to be identified
through small image position shifts during transit. We also re-evaluate Kepler
Objects of Interest (KOI) 1-1609, which were identified early in the mission,
using substantially more data to test for background false positives and to
find additional multiple systems. Combining the new and previous KOI samples,
we provide updated parameters for 2,738 Kepler planet candidates distributed
across 2,017 host stars. From the combined Kepler planet candidates, 472 are
new from the Q1-Q8 data examined in this study. The new Kepler planet
candidates represent ~40% of the sample with Rp~1 Rearth and represent ~40% of
the low equilibrium temperature (Teq<300 K) sample. We review the known biases
in the current sample of Kepler planet candidates relevant to evaluating planet
population statistics with the current Kepler planet candidate sample.Comment: 12 pages, 8 figures, Accepted ApJ Supplemen
Planetary Candidates Observed by Kepler. VIII. A Fully Automated Catalog With Measured Completeness and Reliability Based on Data Release 25
We present the Kepler Object of Interest (KOI) catalog of transiting
exoplanets based on searching four years of Kepler time series photometry (Data
Release 25, Q1-Q17). The catalog contains 8054 KOIs of which 4034 are planet
candidates with periods between 0.25 and 632 days. Of these candidates, 219 are
new and include two in multi-planet systems (KOI-82.06 and KOI-2926.05), and
ten high-reliability, terrestrial-size, habitable zone candidates. This catalog
was created using a tool called the Robovetter which automatically vets the
DR25 Threshold Crossing Events (TCEs, Twicken et al. 2016). The Robovetter also
vetted simulated data sets and measured how well it was able to separate TCEs
caused by noise from those caused by low signal-to-noise transits. We discusses
the Robovetter and the metrics it uses to sort TCEs. For orbital periods less
than 100 days the Robovetter completeness (the fraction of simulated transits
that are determined to be planet candidates) across all observed stars is
greater than 85%. For the same period range, the catalog reliability (the
fraction of candidates that are not due to instrumental or stellar noise) is
greater than 98%. However, for low signal-to-noise candidates between 200 and
500 days around FGK dwarf stars, the Robovetter is 76.7% complete and the
catalog is 50.5% reliable. The KOI catalog, the transit fits and all of the
simulated data used to characterize this catalog are available at the NASA
Exoplanet Archive.Comment: 61 pages, 23 Figures, 9 Tables, Accepted to The Astrophysical Journal
Supplement Serie
Clinical population pharmacokinetics and toxicodynamics of linezolid
Thrombocytopenia is a common side effect of linezolid, an oxazolidinone antibiotic often used to treat multidrug-resistant Gram-positive bacterial infections. Various risk factors have been suggested, including linezolid dose and duration of therapy, baseline platelet counts, and renal dysfunction; still, the mechanisms behind this potentially treatment-limiting toxicity are largely unknown. A clinical study was conducted to investigate the relationship between linezolid pharmacokinetics and toxico-dynamics and inform strategies to prevent and manage linezolid-associated toxicity. Forty-one patients received 42 separate treatment courses of linezolid (600 mg every 12 h). A new mechanism-based, population pharmacokinetic/toxicodynamic model was developed to describe the time course of plasma linezolid concentrations and platelets. A linezolid concentration of 8.06 mg/ liter (101% between-patient variability) inhibited the synthesis of platelet precursor cells by 50%. Simulations predicted treatment durations of 5 and 7 days to carry a substantially lower risk than 10- to 28-day therapy for platelet nadirs o
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