Agri-Environmental Policies in a Transition Economy: Using a Choice Experiment to Value Agricultural Biodiversity on Hungarian Small Farms

Agricultural biodiversity is a crucial environmental resource. Much of the agricultural biodiversity remaining today is found on the semi-subsistence farms of poorer countries and on the small-scale farms and home gardens of more industrialised nations. The traditional Hungarian home gardens, which serve as small farms, are an example. Historically, these home gardens have served important functions related to food security, diet quality, and local culture. Some policies related to European Union accession threaten the survival of traditional home gardens in Hungary’s transitional economy. This paper applies the choice experiment method to estimate the value farmers themselves attach to the agricultural biodiversity still found in these micro-agroecosystems. One of several related studies, its aim is to enhance policy understanding of the role of Hungarian small farms and home gardens in the National Agri-Environmental Programme. The analysis is based on primary data collected in three environmentally sensitive areas of Hungary where pilot agri-environmental programmes have been initiated. Findings demonstrate the variation in values farmers assign to home gardens across regions and households, with implications for the design of efficient public conservation programmes.Agricultural biodiversity, Conservation, Choice experiment method, Hungary, Home garden

Theoretical Zero Age Main Sequences revisited

Zero Age Main Sequence (ZAMS) models with updated physical inputs are presented for selected assumptions about the chemical composition, covering the ranges 0.6 < M/Mo < 1.2, 0.0001 < Z < 0.04, 0.23 < Y < 0.34.The HR diagram location of the ZAMS as a function of Y and Z is discussed both in the theoretical and in the observational HR diagrams, showing that the V magnitude presents an increased dependence on Z to be taken into account when discussing observational evidences. Analytical relations quantifying both these dependences are derived. Implications for the galactic helium to heavier elements enrichment are finally discussed.Comment: 4 pages, 4 postscript figures, accepted for publication on Astronomy & Astrophysic

Hipparcos open clusters and stellar evolution

By relying on recently improved Hipparcos parallaxes for the Hyades, Pleiades and Ursa Major clusters we find that stellar models with updated physical inputs nicely reproduce the location in the color magnitude diagram of main sequence stars of different metallicities. Stars in the helium burning phase are also discussed, showing that the luminosity of giants in the Hyades, Praesepe and Ursa Major clusters appears to be in reasonable agreement with theoretical predictions. A short discussion concerning the current evolutionary scenarios closes the paper.Comment: 5 pages, 6 Postscript figures, accepted by MNRA

Testing general relativity by micro-arcsecond global astrometry

The global astrometric observations of a GAIA-like satellite were modeled within the PPN formulation of Post-Newtonian gravitation. An extensive experimental campaign based on realistic end-to-end simulations was conducted to establish the sensitivity of global astrometry to the PPN parameter \gamma, which measures the amount of space curvature produced by unit rest mass. The results show that, with just a few thousands of relatively bright, photometrically stable, and astrometrically well behaved single stars, among the ~10^9 objects that will be observed by GAIA, \gamma can be estimated after 1 year of continuous observations with an accuracy of ~10^{-5} at the 3\sigma level. Extrapolation to the full 5-year mission of these results based on the scaling properties of the adjustment procedure utilized suggests that the accuracy of \simeq 2x10^{-7}, at the same 3\sigma level, can be reached with \~10^6 single stars, again chosen as the most astrometrically stable among the millions available in the magnitude range V=12-13. These accuracies compare quite favorably with recent findings of scalar-tensor cosmological models, which predict for \gamma a present-time deviation, |1-\gamma|, from the General Relativity value between 10^{-5} and 10^{-7}.Comment: 7 pages, 2 figures, to be published in A&

The distance to the Pleiades from orbital solution of the double-lined eclipsing binary HD 23642

Combining precise B,V photoelectric photometry and radial velocities, we have been able to derive a firm orbital solution and accurate physical parameters for the newly discovered eclipsing binary HD 23642 in the Pleiades open cluster. The resulting distance to the binary, and therefore to the cluster, is 132 +/- 2 pc. This closely confirms the distance modulus obtained by classical main sequence fitting methods (m-M = 5.60 or 132 pc), moving cluster techniques and the astrometric orbit of Atlas. This is the first time the distance to a member of the Pleiades is derived by orbital solution of a double-lined eclipsing binary, and it is intended to contribute to the ongoing discussion about the discordant Hipparcos distance to the cluster.Comment: accepted in press in A&A as Letter to the Edito

Electric Waterborne Public Transportation in Venice: a Case Study

The paper reports the results of a study for moving the present diesel-based watercraft propulsion technology used for public transportation in Venice city and lagoon to a more efficient and smart electric propulsion technology, in view of its adopted in a near future. Energy generation and storage systems, electrical machines and drives, as well as economic, environmental and social issues are presented and discussed. Some alternative solutions based on hybrid diesel engine and electric and full electric powertrains are compared in terms of weights, costs and payback times. Previews researches on ship propulsion and electric energy storage developed by the University of Padua and preliminary experiences on electric boats carried out in Venice lagoon by the municipal transportation company ACTV and other stakeholders are the starting point for this study. Results can be transferred to other waterborne mobility systems