WATER POLICY AND THE SUSTAINABILITY OF IRRIGATED SYSTEMS IN ITALY

The management of water resources is today one of the main issues in most countries. In Italy, as in many other European countries, irrigation is the main sector using water and hence it is at the centre of the water policy agenda. Water management for irrigation requires suitable policy tools able to meet social objectives and private behaviour. The legal framework in the European Union is today faced with the new Water Framework Directive (60/2000), that sets up new criteria for water management, regulation and pricing. Among other things, the Water Framework Directive introduces the principle of full cost recovery and the polluter pays principle for water users. For many areas of Italy, this may be a significant shift compared to present payment criteria, based on traditional rights, area prices, and only a partial cost recovery from final users. The objective of this paper is to analyse the problem of water regulation for irrigated agriculture, through a simulation model based on the integration of a mathematical decision making model and a principal agent. The methodology allows to quantify water demand and optimal regulation from the point of view of the policy maker. The results show major impacts of water availability and prices on farm income. The adoption of a mix of pricing instruments related at the same time to charges associated to crop mix, water consumption and pollution can significantly improve water policy efficacy.Resource /Energy Economics and Policy,

Frequency map analysis of a three-dimensional particle in the core model of a high intensity linac

We consider the dynamical properties of a particle-core model for a uniformly filled triaxial ellipsoid in a periodic lattice of a high intensity linac. The mismatched oscillation modes are analytically computed in the smooth approximation and are compared with the numerical results of a tracking program. The study of the phase space in the mismatched case is performed by the frequency map analysis. In particular, we can analyze the effect of the nonlinear resonances between the envelope modes and the single particle sincrobetatron frequencies. A chaoticity criterion based on the frequency map analysis allows one to compute the stability region around the beam core. An estimate of the transport and its enhancement due to mismatch is provided by tracking orbits at the border of the stability region

Stochastic Properties of Colliding Hard Spheres in a Non-equilibrium Thermal Bath

We consider the problem of describing the dynamics of a test particle moving in a thermal bath using the stochastic differential equations. We briefly recall the stochastic approach to the Brownian based on the statistical properties of collision theory for a gas of elastic particles and the molecular chaos hypothesis. The mathematical formulation of the Brownian motion leads to the formulation of the Ornstein-Uhlenbeck equation that provides a stationary solution consistent with the Maxwell-Boltzmann distribution. According to the stochastic thermodynamics, we assume that the stochastic differential equations allow to describe the transient states of the test particle dynamics in a thermal bath and it extends their application to the study of the non-equilibrium statistical physics. Then we consider the problem of the dynamics of a test massive particle in a non homogeneous thermal bath where a gradient of temperature is present. We discuss as the existence of a local thermodynamics equilibrium is consistent with a Stratonovich interpretation of the stochastic differential equations with a multiplicative noise. The stochastic model applied to the test particle dynamics implies the existence of a long transient state during which the particle shows a net drift toward the cold region of the system. This effect recalls the thermophoresis phenomenon performed by large molecule in a solution in response to a macroscopic temperature gradient and it can be explained as an effect of the non-locality character of the collision interactions between the test particle and the thermal bath particles. To validate the stochastic model assumptions we analyze the simulation results of the 2-dimensional hard sphere gas obtained by using an event-based computer code, that solves exactly the sphere dynamics. The temperature gradient is simulated by the presence of two reflecting boundary conditions at different temperature. The simulations suggest that existence of a local thermodynamic equilibrium is justified and highlight the presence of a drift in the average dynamics of an ensemble of massive particles. The results of the paper could be relevant for the applications of stochastic dynamical systems to the non-equilibrium statistical physics that is a key issue for the Complex Systems Physics

Seismic assessment and retrofit design of a school building in florence

The recent earthquakes occurred in Italy highlighted again the high vulnerability of structures built before the release of national Seismic Standards. This induced several local authorities to undertake extensive performance assessment campaigns of public buildings, among which mainly schools. A study carried out within one of these campaigns, concerning the evaluation of seismic vulnerability and the design of retrofit interventions in a school building in Florence, is presented herein. The structure was built at the beginning of 1970s, and is characterized by a ground storey with reinforced concrete frame skeleton, and a first and second storey with steel structure. An extensive on-site experimental investigation was developed at a first step of the study, which allowed identifying the mechanical characteristics of the constituting materials, and re-drawing the main structural details. Based on these data, a check of the seismic performance in current conditions was carried out, which highlighted several drawbacks, especially concerning the steel members. This prompted to propose a seismic retrofit hypothesis of the building, consisting in the installation of a set of dissipative braces incorporating fluid viscous dampers as protective devices. A synthesis of the assessment analyses in current conditions and the retrofit design, which allows attaining an elastic structural response up to the maximum considered earthquake level, is reported in the paper

Zonas de reserva campesina: territorios de paz en disputa

El desarrollo rural es quizás uno de los campos más amplios de la agroecología, que en Colombia hace referencia a la conflictividad social y armada emanada de la lucha por la tierra. Este tema ha tomado importancia al interior de la Agenda de Negociación de los diálogos de paz entre el Gobierno Nacional y las FARC-EP. Sin embargo, hace ya décadas que se vienen desarrollando y documentando experiencias alrededor del tema, algunos, de gran importancia y común a escenarios académicos y políticos, son aquellos que tienen que ver con la colonización campesina, particularmente con las Zonas de Reserva Campesina (ZRC), las cuales, consagradas en Ley 160 de 1994 son una propuesta de las comunidades campesinas como una figura de ordenamiento territorial, nacido en un contexto histórico de luchas agrarias desde mediados del siglo XIX en zonas de colonización. Hoy en día estas son el centro de debate no solo por su naturaleza, sino por los alcances que poseen en la búsqueda de la paz.The rural development is maybe one of the largest issues of agroecology, in Colombia it involves the social and armed conkflict emanated by the war for lands. This topic has taken importance at the interior of the negotiation agenda of the peace dialogues between the national government and the “FARC-EP”. However, for decades it has been developing and documenting experiences around this topic, some of them of great importance and common to academic and politic stages, like those that deal with the peasant colonization, particularly with the peasant reserve zones “Zonas de Reserva Campesina (ZRC)”, that are consigned in the law 160 of 1994 and are a proposal of the peasant communities like a figure of zoning, started in a historic context of agrarian struggles since middle of XIX century at colonization zones. Nowadays this is the center of the debate, not only by its nature but by the scope that has on the search for peace.Eje A6: Desarrollo Rural, Movimientos Sociales, Estado y AgroecologíaFacultad de Ciencias Agrarias y Forestale

Image Search with Text Feedback by Visiolinguistic Attention Learning

Image search with text feedback has promising impacts in various real-world applications, such as e-commerce and internet search. Given a reference image and text feedback from user, the goal is to retrieve images that not only resemble the input image, but also change certain aspects in accordance with the given text. This is a challenging task as it requires the synergistic understanding of both image and text. In this work, we tackle this task by a novel Visiolinguistic Attention Learning (VAL) framework. Specifically, we propose a composite transformer that can be seamlessly plugged in a CNN to selectively preserve and transform the visual features conditioned on language semantics. By inserting multiple composite transformers at varying depths, VAL is incentive to encapsulate the multi-granular visiolinguistic information, thus yielding an expressive representation for effective image search. We conduct comprehensive evaluation on three datasets: Fashion200k, Shoes and FashionIQ. Extensive experiments show our model exceeds existing approaches on all datasets, demonstrating consistent superiority in coping with various text feedbacks, including attribute-like and natural language descriptions

Eigenvalue Distributions for a Class of Covariance Matrices with Applications to Bienenstock-Cooper-Munro Neurons Under Noisy Conditions

We analyze the effects of noise correlations in the input to, or among, BCM neurons using the Wigner semicircular law to construct random, positive-definite symmetric correlation matrices and compute their eigenvalue distributions. In the finite dimensional case, we compare our analytic results with numerical simulations and show the effects of correlations on the lifetimes of synaptic strengths in various visual environments. These correlations can be due either to correlations in the noise from the input LGN neurons, or correlations in the variability of lateral connections in a network of neurons. In particular, we find that for fixed dimensionality, a large noise variance can give rise to long lifetimes of synaptic strengths. This may be of physiological significance.Comment: 7 pages, 7 figure

Zonas de reserva campesina: territorios de paz en disputa

El desarrollo rural es quizás uno de los campos más amplios de la agroecología, que en Colombia hace referencia a la conflictividad social y armada emanada de la lucha por la tierra. Este tema ha tomado importancia al interior de la Agenda de Negociación de los diálogos de paz entre el Gobierno Nacional y las FARC-EP. Sin embargo, hace ya décadas que se vienen desarrollando y documentando experiencias alrededor del tema, algunos, de gran importancia y común a escenarios académicos y políticos, son aquellos que tienen que ver con la colonización campesina, particularmente con las Zonas de Reserva Campesina (ZRC), las cuales, consagradas en Ley 160 de 1994 son una propuesta de las comunidades campesinas como una figura de ordenamiento territorial, nacido en un contexto histórico de luchas agrarias desde mediados del siglo XIX en zonas de colonización. Hoy en día estas son el centro de debate no solo por su naturaleza, sino por los alcances que poseen en la búsqueda de la paz.The rural development is maybe one of the largest issues of agroecology, in Colombia it involves the social and armed conkflict emanated by the war for lands. This topic has taken importance at the interior of the negotiation agenda of the peace dialogues between the national government and the “FARC-EP”. However, for decades it has been developing and documenting experiences around this topic, some of them of great importance and common to academic and politic stages, like those that deal with the peasant colonization, particularly with the peasant reserve zones “Zonas de Reserva Campesina (ZRC)”, that are consigned in the law 160 of 1994 and are a proposal of the peasant communities like a figure of zoning, started in a historic context of agrarian struggles since middle of XIX century at colonization zones. Nowadays this is the center of the debate, not only by its nature but by the scope that has on the search for peace.Eje A6: Desarrollo Rural, Movimientos Sociales, Estado y AgroecologíaFacultad de Ciencias Agrarias y Forestale

Gut microbiota ecology: Biodiversity estimated from hybrid neutral-niche model increases with health status and aging

In this work we propose an index to estimate the gut microbiota biodiversity using a modeling approach with the aim of describing its relationship with health and aging. The gut microbiota, a complex ecosystem that links nutrition and metabolism, has a pervasive effect on all body organs and systems, undergoes profound changes with age and life-style, and substantially contributes to the pathogenesis of age-related diseases. For these reasons, the gut microbiota is a suitable candidate for assessing and quantifying healthy aging, i.e. the capability of individuals to reach an advanced age, avoiding or postponing major age-related diseases. The importance of the gut microbiota in health and aging has been proven to be related not only to its taxonomic composition, but also to its ecological properties, namely its biodiversity. Following an ecological approach, here we intended to characterize the relationship between the gut microbiota biodiversity and healthy aging through the development a parsimonious model of gut microbiota from which biodiversity can be estimated. We analysed publicly available metagenomic data relative to subjects of different ages, countries, nutritional habits and health status and we showed that a hybrid niche-neutral model well describes the observed patterns of bacterial relative abundance. Moreover, starting from such ecological modeling, we derived an estimate of the gut microbiota biodiversity that is consistent with classical indices, while having a higher statistical power. This allowed us to unveil an increase of the gut microbiota biodiversity during aging and to provide a good predictor of health status in old age, dependent on life-style and aging disorders