3,920 research outputs found
Situacion del cultivo de frijol en America Latina
L.A. is the largest producer of field beans in the world (34 percent - av. of 3.85 million t/yr from 1968-71), Brazil alone accounting for more than 50 percent. Productivity is low, ranging from 330-1164 kg/ha (av 600 kg). Most of the beans are grown on small farms, often in association with other crops, especially maize. Cultural practices in the different countries are summarized. Tables show the frequency of diseases, pests (grouped according to type of damage caused) and weeds in the different L.A. countries and several regions of Brazil. Other important problems are poor rainfall distribution, the inefficiency of the marketing system and the lack of price controls. Research allocations are few and seed production policy does not have sufficient impact. Restructuration of national programs, training of research personnel and obtention of capital for greater credit facilities are recommended. On-farm studies should be conducted to determine the participation of beans as a source of income, nutrition and employment. (CIAT
Energy prices in Europe. Evidence of persistence across markets
This paper deals with the behavior of energy price changes and how their shocks exert an impact on suppliers and
consumers in different markets. For this purpose, a fractional integration model is used to evaluate the persistence and mean reversion in prices across the major European markets (Germany, France, Italy, UK, Spain). We
compare the results with other major players as the US and Japan, to understand, first, if the European behavior
is different, and second, if geopolitical shocks that are affecting this market are expected to be permanent.
Empirical results show evidence of mean reversion properties in European prices, though some minor differences
arise from market to market that apparently, are not associated with the energy generation strategies followed by
each country. Thus, it will likely be expected following the current energy shocks the series will recover due to
natural market forces, without the need for additional policies
Persistence in UK historical data on life expectancy
This paper provides estimates of persistence in historical UK data on life expectancy
applying fractional integration methods to both an annual series from 1842 to 2019
and a 5-year average from 1543 to 2019. This method is the most appropriate for our
purposes since it is more general and fexible than the classical methods based on
integer diferentiation. The results indicate that the former exhibits an upward trend
and is persistent but mean reverting; the same holds for the latter, though its degree
of persistence is higher. Similar results are obtained for the logged values. On the
whole, this evidence suggests that the efects of shocks to the series are transitory
though persistent, which is useful information for policy makers whose task is to
take appropriate measures to increase life expectancy
Quasars Clustering at z approx 3 on Scales less sim 10 h^{-1} Mpc
We test the hypothesis whether high redshift QSOs would preferentially appear
in small groups or pairs, and if they are associated with massive, young
clusters. We carried out a photometric search for \Ly emitters on scales
Mpc, in the fields of a sample of 47 known
QSOs. Wide and narrow band filter color-magnitude diagrams were generated for
each of the fields. A total of 13 non resolved objects with a
significant color excess were detected as QSO candidates at a redshift similar
to that of the target. All the candidates are significantly fainter than the
reference QSOs, with only 2 of them within 2 magnitudes of the central object.
Follow-up spectroscopic observations have shown that 5, i.e., about 40% of the
candidates, are QSOs at the same redshift of the target; 4 are QSOs at
different z (two of them probably being a lensed pair at z = 1.47); 2
candidates are unresolved HII galaxies at z0.3; one unclassified and one
candidate turned out to be a CCD flaw. These data indicate that at least 10% of
the QSOs at z3 do have companions.
We have also detected a number of resolved, rather bright \Ly Emitter
Candidates. Most probably a large fraction of them might be bright galaxies
with [OII] emission, at z 0.3. The fainter population of our
candidates corresponds to the current expectations. Thus, there are no strong
indication for the existence of an overdensity of \Ly galaxies brighter than m
25 around QSOs at 3.Comment: 29 pages, 8 figures, tar gzip LaTex file, accepted to appear in Ap
New Structure In The Shapley Supercluster
We present new radial velocities for 189 galaxies in a 91 sq. deg region of
the Shapley supercluster measured with the FLAIR-II spectrograph on the UK
Schmidt Telescope. The data reveal two sheets of galaxies linking the major
concentrations of the supercluster. The supercluster is not flattened in
Declination as was suggested previously and it may be at least 30 percent
larger than previously thought with a correspondingly larger contribution to
the motion of the Local Group.Comment: LaTex: 2 pages, 1 figure, includes conf_iap.sty style file. To appear
in proceedings of The 14th IAP Colloquium: Wide Field Surveys in Cosmology,
held in Paris, 1998 May 26--30, eds. S.Colombi, Y.Mellie
The importance of vitamin D and omega-3 PUFA supplementation: a nonpharmacologic immunomodulation strategy to halt autoimmunity
The large, randomized, double-blind, placebo-controlled trial VITAL (Vitamin D and omega 3 trial) recently confirmed that vitamin D and omega-3 polyunsaturated fatty acid (PUFA) co-supplementation (VIDOM) can reduce the incidence of autoimmune diseases. Based on these relevant results, this commentary summarizes the molecular mechanisms behind the anti-inflammatory and immunomodulatory properties of vitamin D and omega-3 PUFAs. We also describe the potential bidirectional interplay between vitamin D metabolism and omega-3 PUFA metabolism that underlies the rationale for VIDOM co-supplementation and that may contribute to enhance the anti-inflammatory and immunomodulatory actions of vitamin D and omega-3 PUFAs when these compounds are administered in combination
Potential of remote sensing data to support the seismic safety assessment of reinforced concrete buildings affected by slow-moving landslides
Different forms of hazard can affect structures throughout their existence. The occurrence of a seismic event in areas exposed to different risks or already affected by other phenomena is highly likely, especially in countries characterized by high seismicity and equally high hydrogeological risk, as Italy. Nevertheless, the seismic safety assessment of reinforced concrete (RC) structures is commonly carried out considering the seismic action only, generally applied to an analytical model, neglecting the stress–strain state induced by previous ongoing phenomena. The aim of this work is to highlight the importance of the seismic safety assessment in a multi-hazard analysis, cumulating the action coming from two different hazards: landslide and earthquake. An existing RC building, located in an area affected by an intermittent landslide phenomenon with slow kinematics, that may also be subjected to strong earthquakes, is used as case study. The Differential Synthetic Aperture Radar Interferometry (DInSAR) approach is used to monitor the evolution in time of the landslide. DInSAR deformation data are used to detect surface ground movements applied to building foundations. A non-linear static analysis procedure is implemented for the code-based seismic safety assessment, in two different scenarios. The seismic assessment of the case-study building is implemented in a condition of structure deformed only for gravity loads, and, then, in a state of known landslide-induced deformed configuration. A comparison is proposed between the building seismic safety assessment performed in both cases, with or without the consideration of the landslide-induced displacements, showing the importance of a multi-hazard evaluation
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