1,544 research outputs found
Coordination and Miss-Coordination in Market Entry Games with an Application to Congestion Externalities
Marketing,
Do Natural Disasters Affect Trust/Trustworthiness? Evidence from the 2010 Chilean Earthquake
A series of trust games were conducted in Chile to analyze whether the past 2010 earthquake affected trust and trustworthiness in rural communities. Results show that trust levels are invariant between villages affected by the earthquake and villages not affected by this shock (control group). However, we find statistical evidence that trustworthiness has diminished in areas affected by the earthquake. Results are relevant for policy regarding aid and recovery of communities affected by these types of disasters.Trust games, natural disasters, trustworthiness, Community/Rural/Urban Development, International Development, C93, O13,
Synchronous and Asynchronous Recursive Random Scale-Free Nets
We investigate the differences between scale-free recursive nets constructed
by a synchronous, deterministic updating rule (e.g., Apollonian nets), versus
an asynchronous, random sequential updating rule (e.g., random Apollonian
nets). We show that the dramatic discrepancies observed recently for the degree
exponent in these two cases result from a biased choice of the units to be
updated sequentially in the asynchronous version
Testing for Yield Persistency: Is It Skill or is It Luck?
This study uses corn yield data from McLean County, Illinois to test whether farmer skill influences yields. This analysis is conducted by performing persistency tests on unadjusted, soil productivity adjusted (PA), and productivity and input intensity adjusted (PIA) yields. Correlation analysis and winner/loser tables indicate that unadjusted, PA, and PIA yields exhibit persistency across time. PIA yields exhibiting persistency is consistent with farmer skill influencing yield. Hence, our results support the hypothesis that farmer skill influences yields.Crop Production/Industries,
Understanding the causes and consequences of high-carotene Cassava roots
A large dataset (2129 data points) was developed over the years of research to increase carotenoids content in cassava roots. Correlations were always based on more than 550 data points. Correlations between dry matter content (DMC) and total carotene content (TCC) or ?- carotene (TBC) were positive and weak (0.13 and 0.07, respectively). There is no problem, therefore, for producing biofortified cassava with adequate levels of DMC. Correlation between cyanogenic potential (HCN) and TCC was negative suggesting that it is possible to obtain highcarotene with low HCN values. Correlations of data from spectrophotometer and HPLC were very high. TCC and TBC had a high correlation (0.90) suggesting that most carotenoids in cassava roots are ?-carotene. Correlations between TCC and TBC with phytoene were relatively high (0.52 and 0.61, respectively). Correlations between TCC and TBC with phytofluene were 0.60 and 0.65, respectively. Correlation between phytoene and phytofluene was 0.96. No case where accumulation of phytoene or phytofluene without parallel levels of carotenoids was observed. Similarly there was no accumulation of phytoene without parallel levels of phtytofluene. There is no evidence, therefore, that accumulation of carotenoids in cassava roots is related to a blockage at the PSY or PDS steps in the carotenoids biosynthesis. (Résumé d'auteur
CAFE: Calar Alto Fiber-fed Echelle spectrograph
We present here CAFE, the Calar Alto Fiber-fed Echelle spectrograph, a new
instrument built at the Centro Astronomico Hispano Alem\'an (CAHA). CAFE is a
single fiber, high-resolution (70000) spectrograph, covering the
wavelength range between 3650-9800\AA. It was built on the basis of the common
design for Echelle spectrographs. Its main aim is to measure radial velocities
of stellar objects up to 13-14 mag with a precision as good as a few
tens of . To achieve this goal the design was simplified at maximum,
removing all possible movable components, the central wavelength is fixed, so
the wavelentgth coverage; no filter wheel, one slit and so on, with a
particular care taken in the thermal and mechanical stability. The instrument
is fully operational and publically accessible at the 2.2m telescope of the
Calar Alto Observatory.
In this article we describe (i) the design, summarizing its manufacturing
phase; (ii) characterize the main properties of the instrument; (iii) describe
the reduction pipeline; and (iv) show the results from the first light and
commissioning runs. The preliminar results indicate that the instrument fulfill
the specifications and it can achieve the foreseen goals. In particular, they
show that the instrument is more efficient than anticipated, reaching a
20 for a stellar object as faint as 14.5 mag in 2700s
integration time. The instrument is a wonderful machine for exoplanetary
research (by studying large samples of possible systems cotaining massive
planets), galactic dynamics (high precise radial velocities in moving groups or
stellar associations) or astrochemistry.Comment: 12 pages, 23 figures; Acepted for publishing in A&A, 201
Sovereign risk, private credit, and stabilization policies
In this paper we examine the impact of bailout policies in small open economies that are subject to financial frictions. We extend standard endogenous default models in two ways. First, we augment the government’s choice set with a bailout option. In addition to the standard choice of defaulting or repaying the debt, a government can also choose to ask for third-party bailout, which comes at a cost of an imposed borrowing limit. Second, we introduce financial frictions and a financial intermediation channel, which tie conditions on the private credit market to the conditions on the sovereign credit market. This link has been very strong in European countries during the recent sovereign crisis. We find that the existence of a bailout option reduces sovereign spreads and, through the described link, private credit rates as well. The implementation of a rescue program reduces output losses and increases welfare, measured in consumption equivalent terms. Moreover, bailout benefits emerge even when a government only has the option of asking for a bailout, but does not take advantage of it
Utilization of NIRS and Minolta Chromameter in selection for increased carotenoids content in cassava roots. [SP10-03]
Significant progress has been made increasing carotenoids content in cassava roots. The information was used to test the usefulness of NIRs and the Minolta Chromameter in predicting carotenoids content (and other relevant traits). Quantification was made of fresh root tissue (not lyophilized). The dataset (2129 data points) was first cleaned of outlying or suspicious data points to develop reliable prediction equations. R2 values between NIRs prediction and actual measurements were 0.91 for total carotenoids content (TCC); 0.93 for total ?-carotene (TBC), and 0.95 for dry matter content, but is less efficient for cyanogenic potential (0,81). Standard error of cross validation (SECV) for TCC and TBC were (1.191 and 0.837, respectively) while the residual predictive deviations (RPD) were also acceptable (above 3.0). These results suggest that NIRs can be used to reliably predict different variables based on fresh root samples. The Minolta Chromameter can also be used for pre-selection as its R2 values were 0.58 for TCC and 0.64 for TBC. Relative concentration of different carotenoids and precursors did not suggest the existence of a major blockage in the metabolic pathway towards the synthesis of ?-carotene. Once phytoene is synthesized most to the different pigments in the metabolic pathway are found, as expected, in correlated proportions. (Résumé d'auteur
Discovery of a massive X-ray luminous galaxy cluster at z=1.579
We report on the discovery of a very distant galaxy cluster serendipitously
detected in the archive of the XMM-Newton mission, within the scope of the
XMM-Newton Distant Cluster Project (XDCP). XMMUJ0044.0-2033 was detected at a
high significance level (5sigma) as a compact, but significantly extended
source in the X-ray data, with a soft-band flux f(r<40")=(1.5+-0.3)x10^(-14)
erg/s/cm2. Optical/NIR follow-up observations confirmed the presence of an
overdensity of red galaxies matching the X-ray emission. The cluster was
spectroscopically confirmed to be at z=1.579 using ground-based VLT/FORS2
spectroscopy. The analysis of the I-H colour-magnitude diagram shows a sequence
of red galaxies with a colour range [3.7 < I-H < 4.6] within 1' from the
cluster X-ray emission peak. However, the three spectroscopic members (all with
complex morphology) have significantly bluer colours relative to the observed
red-sequence. In addition, two of the three cluster members have [OII]
emission, indicative of on-going star formation. Using the spectroscopic
redshift we estimated the X-ray bolometric luminosity, Lbol = 5.8x10^44 erg/s,
implying a massive galaxy cluster. This places XMMU J0044.0-2033 at the
forefront of massive distant clusters, closing the gap between lower redshift
systems and recently discovered proto- and low-mass clusters at z >1.6.Comment: letter to appear in A&
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