351 research outputs found
Multifunctional Agriculture, Quality of Life and Policy Decisions: an Empirical Case
The TOP-MARD research project (Toward a Policy Model of Multifunctional Agriculture and Rural Development), that will be here described in its Italian version, links farmersâ behaviour with their economic, social and environmental effects, showing the difference between a behaviour guided by market profitability only and one guided by the interest of a broader social group. It was financed by EU in 11 European countries, and it took place in 2006-2008. The TOP-MARD research defined a 10-modules model (POMMARD), that links use of land and production techniques to several dimensions of a context (quantitative and qualitative, from economic to social and environmental) and to the quality of life of its population. STELLA, a Systems Thinking software, has been used in order to develop the POMMARD model. The POMMARD model is partially supply-driven with demand constraints: land use and its dynamics produce a mix of marketable and non-marketable goods, that impact other sectors and the territory through an I-O or a SAM, and through the consequences of their production on the quality of life. Labour requirements and demography can produce â therefore â immigration, and contribute to job creation and dynamics. Public intervention influences local resources and human behaviour. Farmers can choose their style of production and land use, that are the âkey driversâ of change: when land is converted from a land use to another or from a conventional to a non-conventional style of production, there occurs a change in the vector of inputs (means of production and workers) and in the vector of outputs, that also comprehends public goods. Provision of public goods increases the quality of life. Rural areas become therefore more attractive to younger generations, encouraging them to stay rather than migrate, and attracting new-comers. Tourism can also be influenced by the attractiveness of the area, which can contribute further income, within the limits of tourism capacity and seasonality. Starting from the actual systematic links, the model considers the main variables (population, income, âŠ) under different policy scenarios: providing suggestions to policy makers about the possible effects of exogenous shocks, such as policy measures, on rural development and quality of life.Multifunctional Agriculture, Quality of Life, Policy Decision., Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development, Food Consumption/Nutrition/Food Safety, Labor and Human Capital,
Finding the Higgs Boson through Supersymmetry
The study of displaced vertices containing two b--jets may provide a double
discovery at the Large Hadron Collider (LHC): we show how it may not only
reveal evidence for supersymmetry, but also provide a way to uncover the Higgs
boson necessary in the formulation of the electroweak theory in a large region
of the parameter space. We quantify this explicitly using the simplest minimal
supergravity model with bilinear breaking of R-parity, which accounts for the
observed pattern of neutrino masses and mixings seen in neutrino oscillation
experiments.Comment: 7 pages, 7 figures. Final version to appear at PRD. Discussion and
results were enlarge
Rare decay Z --> neutrino antineutrino photon photon via quartic gauge boson couplings
We present a detailed calculation of the rare decay Z --> neutrino
antineutrino photon photon via the quartic neutral gauge boson coupling
Z-Z-photon-photon in the framework of the effective Lagrangian approach. The
current experimental bound on this decay mode is then used to constrain the
coefficients of this coupling. It is found that the bounds obtained in this
way, of the order of , are weaker than the ones obtained from the
analysis of triple-boson production at LEP-2Comment: 5 pages, 2 figures, to appear in Physical Review D Brief Report
Supersymmetric Higgs pair discovery prospects at hadron colliders
We study the potential of hadron colliders in the search for the pair
production of neutral Higgs bosons in the framework of the Minimal
Supersymmetric Standard Model. Using analytical expressions for the relevant
amplitudes, we perform a detailed signal and background analysis, working out
efficient kinematical cuts for the extraction of the signal. The important role
of squark loop contributions to the signal is emphasised. If the signal is
sufficiently enhanced by these contributions, it could even be observable at
the next run of the upgraded Tevatron collider in the near future. At the LHC
the pair production of light and heavy Higgs bosons might be detectable
simultaneously.Comment: 5 pages, hep99, 6 figures; Presented at the International Europhysics
Conference on High Energy Physics, Tampere, Finland, 15-21 July 199
Probing Neutrino Oscillations in Supersymmetric Models at the Large Hadron Collider
The lightest supersymmetric particle may decay with branching ratios that
correlate with neutrino oscillation parameters. In this case the CERN Large
Hadron Collider (LHC) has the potential to probe the atmospheric neutrino
mixing angle with sensitivity competitive to its low-energy determination by
underground experiments. Under realistic detection assumptions, we identify the
necessary conditions for the experiments at CERN's LHC to probe the simplest
scenario for neutrino masses induced by minimal supergravity with bilinear R
parity violation.Comment: 11 pages, 6 figures. To appear in Physical Review
Damped harmonic oscillators in the holomorphic representation
Quantum dynamical semigroups are applied to the study of the time evolution
of harmonic oscillators, both bosonic and fermionic. Explicit expressions for
the density matrices describing the states of these systems are derived using
the holomorphic representation. Bosonic and fermionic degrees of freedom are
then put together to form a supersymmetric oscillator; the conditions that
assure supersymmetry invariance of the corresponding dynamical equations are
explicitly derived.Comment: 19 pages, plain-TeX, no figure
Limits on Anomalous Top Couplings from Z Pole Physics
We obtain constraints on possible anomalous interactions of the top quark
with the electroweak vector bosons arising from the precision measurements at
the Z pole. In the framework of chiral Lagrangians, we
examine all effective CP-conserving operators of dimension five which induce
fermionic currents involving the top quark. We constrain the magnitudes of
these anomalous interactions by evaluating their one-loop contributions to the
Z pole physics. Our analysis shows that the operators that contribute to the
LEP observables get bounds close to the theoretical expectation for their
anomalous couplings. We also show that those which break the
custodial symmetry are more strongly bounded.Comment: expanded version, 14 pages, 1 figures adde
Sustainability perspectives: a new methodological approach for quantitative assessment
This paper proposes a new tool to assess sustainability and make the concept
of sustainable development operational. It considers its multi-dimensional
structure combining the information deriving from a selection of relevant
sustainability indicators belonging to economic, social and environmental
pillars. The main novelties of this approach are the modelling framework, a
recursive-dynamic computable general equilibrium used to calculate the trend
of all indicators over time throughout the world, and the aggregation
methodology to reconcile them in one aggregate index to measure overall
sustainability. The former allows capturing the sector and regional
interactions and higher-order effects driven by background assumptions on
relevant variables to depict future scenarios. The latter makes it possible to
compare sustainability performances, under alternative scenarios, across
countries and over time. Main results show that the current sustainability at
world level differs from what the traditional measure of well-being, the GDP,
depicts, highlighting the trade-offs among different components of
sustainability. Moreover, in the next decade a slight decrease in world
sustainability may occur, in spite of an expected increase in world domestic
product. Finally, dedicated policies increase overall sustainability, showing
that social and environmental benefits may be greater than the correlated
economic costs
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