The price stabilization effects of the EU entry price scheme for fruits and vegetables

The paper assesses the stabilization effects of the EU import regime for fresh fruit and vegetables based on the entry price system. The analysis is carried out on the EU prices of tomatoes and lemons and those of imports from some of the main competing countries on the EU domestic markets: Morocco, Argentina and Turkey. It is based on the estimation of a threshold vector autoregressive econometric model that is shown capable of taking the workings of the import regime into account. The model shows that prices behave differently when import prices are above/below the trigger entry price. This paper allowed to highlight the cases for which the isolation effect of EPS seems reached and the resulting stabilization effects

The price stabilization effects of the EU entry price scheme for fruits and vegetables

The paper assesses the stabilization effects of the EU import regime for fresh fruit and vegetables based on the entry price system. The analysis is carried out on the EU prices of tomatoes and lemons and those of imports from some of the main competing countries on the EU domestic markets: Morocco, Argentina and Turkey. It is based on the estimation of a threshold vector autoregressive econometric model that is shown capable of taking the workings of the import regime into account. The model shows that prices behave differently when import prices are above/below the trigger entry price. This paper allowed to highlight the cases for which the isolation effect of EPS seems reached and the resulting stabilization effects.Fruit and vegetables; Entry price system; stabilisation effects; TVAR

The Price Stabilisation Effects of the EU import regime of fruit and vegetables: the case of tomatoes

The paper assesses the stabilization effects of the EU import regime for fresh fruit and vegetables based on the entry price system. The analysis is carried out on the EU prices of tomatoes and those of imports from Morocco, the main competing country on the EU domestic markets. It is based on the estimation of a threshold vector autoregressive econometric model that is shown capable of taking the workings of the import regime into account. The model shows that when prices of tomato imports are below the trigger entry prices the EU tomato market becomes isolated. However, the contribution of the import regime on price stabilization is rather limited. Since tomato imports from Morocco are granted zero tariff if their price is higher than the trigger entry price within a yearly quota that is completely filled, the largest contribution to market stabilization may well come from the size of the quota.fruit and vegetables, European Union , entry prices, trade preferences, price stabilization , tomatoes

Many valued logics: interpretations, representations and applications

2015 - 2016This thesis, as the research activity of the author, is devoted to establish new connections and to strengthen well-established relations between different branches of mathematics, via logic tools. Two main many valued logics, logic of balance and L ukasiewicz logic, are considered; their associated algebraic structures will be studied with different tools and these techniques will be applied in social choice theory and artificial neural networks. The thesis is structured in three parts. Part I The logic of balance, for short Bal(H), is introduced. It is showed: the relation with `-Groups, i.e. lattice ordered abelian groups (Chapter 2); a functional representation (Chapter 3); the algebraic geometry of the variety of `-Groups with constants (Chapter 4). Part II A brief historical introduction of L ukasiewicz logic and its extensions is provided. It is showed: a functional representation via generalized states (Chapter 5); a non-linear model for MV-algebras and a detailed study of it, culminating in a categorical theorem (Chapter 6). Part III Applications to social choice theory and artificial neural network are presented. In particular: preferences will be related to vector lattices and their cones, recalling the relation between polynomials and cones studied in Chapter 4; multilayer perceptrons will be elements of non-linear models introduced in Chapter 6 and networks will take advantages from polynomial completeness, which is studied in Chapter 2. We are going to present: in Sections 1.2 and 1.3 all the considered structures, our approach to them and their (possible) applications; in Section 1.4 a focus on the representation theory for `-Groups and MV-algebras. Note that: algebraic geometry for `-Groups provides a modus operandi which turns out to be useful not only in theoretical field, but also in applications, opening (we hope) new perspectives and intuitions, as we made in this first approach to social theory; non-linear models here presented and their relation to neural networks seem to be very promising, giving both intuitive and formal approach to many concrete problems, for instance degenerative diseases or distorted signals. All these interesting topics will be studied in future works of the author. [edited by author]Questa tesi, come l’attivit`a di ricerca dell’autore, `e dedicata a stabilire nuove connessioni e a rafforzare le relazioni ben consolidate tra diversi settori della matematica, attraverso strumenti logici. Sono considerate due principali logiche a piu` valori, logic of balance e L ukasiewicz logic; le loro strutture algebriche associate verranno studiate con strumenti diversi e queste tecniche saranno applicate nella teoria della scelta sociale e nelle reti neurali artificiali. La tesi `e strutturata in tre parti. Part I Viene introdotta la Logic of balance. Viene mostrato: la relazione con `-Groups, gruppi abeliani ordinati reticolarmente (Chapter 2); una rappresentazione funzionale (Chapter 3); geometria algebrica della variet`a degli `-Groups con costanti (Chapter 4). Part II Viene fornita una breve introduzione storica della logica di L ukasiewicz e delle sue estensioni. Viene mostrato: una rappresentazione funzionale tramite stati generalizzati (Chapter 5); Un modello non lineare per le MV-algebre e uno studio dettagliato di esso, culminando in un teorema categoriale (Chapter 6). Part III Sono presentate applicazioni alla teoria delle scelte sociali e delle rete neurali artificiali. In particolare: le preferenze saranno correlate ai reticoli vettoriali e ai loro coni, richiamando la relazione tra polinomi e coni studiati nel Capitolo 4; I multilayer perceptrons saranno elementi di modelli non lineari introdotti nel Capitolo 6 e le reti prenderanno vantaggi dalla completezza polinomiale, studiata nel Capitolo 2. La geometria algebrica per gli `-Groups fornisce un modus operandi che risulta utile non solo nel campo teorico, ma anche nelle applicazioni, aprendo (speriamo) nuove prospettive e intuizioni, come abbiamo fatto in questo primo approccio alla teoria sociale; I modelli non lineari qui presentati e la loro relazione con le reti neurali sembrano molto promettenti, offrendo un approccio intuitivo e formale a molti problemi concreti, ad esempio malattie degenerative o segnali distorti. Tutti questi argomenti saranno oggetto di studio in opere future dell’autore. [a cura dell'autore]XV n.s. (XXIX

The price stabilization effects of the EU entry price scheme for fruit and vegetables

The article assesses the stabilization effects of the EU import regime for fresh fruit and vegetables based on the entry price system (EPS). The analysis is carried out on the EU prices of tomatoes and lemons and those of imports from some of the main competing countries on the EU domestic markets: Morocco, Argentina, and Turkey. It is based on the estimation of a threshold vector autoregressive econometric model that is shown capable of taking the workings of the import regime into account. The model shows that prices behave differently when import prices are above/below the trigger entry price. This article allowed to highlight the cases for which the isolation effect of EPS seems reached and the resulting stabilization effects. © 2011 International Association of Agricultural Economists

Dynamic Łukasiewicz logic and its application to immune system

AbstractIt is introduced an immune dynamicn-valued Łukasiewicz logicID{\L }_nIDŁnon the base ofn-valued Łukasiewicz logic{\L }_nŁnand corresponding to it immune dynamic$$MV_n$$MVn-algebra ($$IDL_n$$IDLn-algebra),$$1< n < \omega$$1<n<ω, which are algebraic counterparts of the logic, that in turn represent two-sorted algebras$$(\mathcal {M}, \mathcal {R}, \Diamond )$$(M,R,◊)that combine the varieties of$$MV_n$$MVn-algebras$$\mathcal {M} = (M, \oplus , \odot , \sim , 0,1)$$M=(M,⊕,⊙,∼,0,1)and regular algebras$$\mathcal {R} = (R,\cup , ;, ^*)$$R=(R,∪,;,∗)into a single finitely axiomatized variety resemblingR-module with "scalar" multiplication$$\Diamond$$◊. Kripke semantics is developed for immune dynamic Łukasiewicz logicID{\L }_nIDŁnwith application in immune system

Aerated Buffalo Slurry Improves Spinach Plant Growth and Mitigates CO2 and N2O Emissions from Soil

Manure management is the main strategy for mitigating gas emissions from livestock farming. In this study, a laboratory-scale experiment was set up to identify suitable conditions to be applied in a farm-scale experiment. The liquid fraction (LF) of slurry was aerobically treated and greenhouse gas emissions from soil were evaluated. Furthermore, the value of treated LF as a fertilizer on spinach plants was also tested. The aeration of LF determined an increase in mean alkalinity due to ammonia loss. The mass fraction of heavy metals also decreased, likely due to the reduction in solubility. After being applied on soil, aerated LF determined lower CO2 and N2O emissions compared to untreated LF due to a reduced nitrogen load. Spinach plants fertilized with treated LF showed a lush growth and exhibited a lower heavy metal mass fraction as well as a higher content of antioxidants compared to plants fertilized with untreated slurry. Our results show that aeration might be an effective alternative for slurry management as it is able to produce an eco-friendly final product with a high fertilizing value

The Logic of Probability: A Trip through Uncertainty

In real life we have to deal with uncertainty, imprecision and vagueness. Many ideas were introduced and studied in detail to manage with these problems. Now we briefly expose the main formal concepts which describe non-ideal situations, i.e. Probability, Statistics and Fuzzy Logic. Probability has recent origins with respect to other branches of mathematics which have deep roots in the past, like geometry or algebra.We may say all this started with Antoine Gombaud, Chevalier de Méré (1607–1684), who asked Blaise Pascal (1623–1662) about gambling with dice. The correspondence between Pierre de Fermat and Blaise Pascal, which began in 1654, initially on these questions, led to the introduction of basic concepts, i.e. probability and expectation. Only in 1657, Christian Huygens in "De Ratiociniis in ludo aleae" proposed a first systematic study of the new branch of mathematics. However, the need of an axiomatic construction of the theory of probability arose to analyze more general and complex situations than gambling. A strong formalization was supplied by the monograph "Foundations of the theory of probability" (1933) by Andrey Nikolaevich Kolmogorov.Statistics represent the most popular application of probability theory, providing research tools in several areas, including physical and natural sciences, technology, psychology, economics and medicine. Statistics are the bridge that connects experimental data to the mathematical theory behind itself.Fuzzy logic, sometime confused with probability, wants to express and formalize all the sentences which are not true or false at all; the philosophical idea is that "everything is a matter of degree" (Zadeh). La logica della probabilità: un viaggio attraverso l’incertezzaNella vita reale ci si trova di fronte a molte situazioni caratterizzate da incertezza, imprecisione, vaghezza. Sono state introdotte diverse modellizzazioni per il trattamento di tali concetti e problemi. Ci proponiamo di esporre sinteticamente alcuni lineamenti fondamentali di Probabilità, Statistica e Fuzzy Logic.La probabilità ha origini recenti rispetto alle altre branche della matematica che hanno profonde radici nel passato, come la geometria o l’algebra.Possiamo dire che un passaggio iniziale importante si è avuto con Antoine Gombaud, Chevalier de Méré (1607-1684), che pose a Blaise Pascal (1623-1662) una questione riguardante il gioco dei dadi. La corrispondenza tra Pierre de Fermat e Blaise Pascal, che ha avuto inizio nel 1654, su questioni simili, ha portato all'introduzione di concetti di base, come probabilità e aspettativa. Successivamente Christian Huygens, in "De ludo Ratiociniis in aleae", ha proposto un primo studio sistematico della nuova branca della matematica. Tuttavia, la necessità di una costruzione assiomatica della teoria della probabilità sorse per l’esigenza di analizzare situazioni più generali e complesse rispetto al gioco d'azzardo. Una forte formalizzazione è stata fornita dalla monografia "Fondamenti della teoria della probabilità" (1933) di Andrey Nikolaevich Kolmogorov.La statistica rappresenta l'applicazione più popolare della teoria della probabilità, fornendo strumenti di ricerca in diversi settori, tra cui le scienze fisiche e naturali, la tecnologia, la psicologia, l'economia e la medicina. In un certo senso essa rappresenta il ponte che collega i dati sperimentali con la teoria matematica.La Logica Fuzzy, da non confondere con la probabilità, si occupa del trattamento formale delle proposizioni di cui non si può affermare senza ambiguità che siano vere o false; l'idea filosofica è che "tutto è una questione di gradualità" (Zadeh).Parole Chiave: Incertezza, Probabilità, Statistica, Fuzz

Changes in eggshell ultrastructure of Falco naumanni and Tyto alba exposed to pesticides and polychlorinated biphenyls (PCBs)

Changes in the quality of eggs of birds exposed to environmental contaminants have been described, but few reports concern eggshell ultrastructure. In this study, infertile or addled Lesser Kestrels (Falco naumanni) and Barn owls (Tyto alba) eggs were collected from the polluted area of Gela plain (Sicily) during 2007, and compared in terms of organophosphate and organochlorine pesticides, and PCBs levels, and eggshell ultrastructure as determined by scanning electron microscopy. Pesticide and PCB residues in eggs were determined by Gas chromatography/ mass spectrometry (GC/MS) [GC Agilent 7890A/MS Agilent 5975C (Agilent technologies) using a DB-5 capillary column in the selected ion monitoring mode]. The GC/MS analysis revealed that eggs contained measurable amounts of some pesticides and PCBs. There was a low detection of organophosphate pesticides while the most abundant organochlorine residues detected were p,p’ DDT, p,p’ DDE, and Hexachlorobenzene. While, the most abundant PCBs detected congeners were PCB 138, 153, 170, 180, and 187. Although the general structure of the eggshell layers was maintained, the results showed ultrastructural differences in mammillary and palisade eggshell layers between high level and low level contaminated eggs in Tyto alba. Furthermore, mammillary cores of the eggshell had an increased distance between themselves with respect to well organized structures present in uncontaminated egg. In this paper we verify the presence of environmental contaminants in the eggs and document structural changes in bird of prey eggshells. The data could suggest that some contaminants can contribute to reduced reproductive performance (infertile or addled egg) by structural changes in the eggshell. The alteration in morphological disposition of mammillary cores could also suggest an impairment of gas exchange

The Price Stabilisation Effects of the EU import regime of fruit and vegetables: the case of tomatoes

The paper assesses the stabilization effects of the EU import regime for fresh fruit and vegetables based on the entry price system. The analysis is carried out on the EU prices of tomatoes and those of imports from Morocco, the main competing country on the EU domestic markets. It is based on the estimation of a threshold vector autoregressive econometric model that is shown capable of taking the workings of the import regime into account. The model shows that when prices of tomato imports are below the trigger entry prices the EU tomato market becomes isolated. However, the contribution of the import regime on price stabilization is rather limited. Since tomato imports from Morocco are granted zero tariff if their price is higher than the trigger entry price within a yearly quota that is completely filled, the largest contribution to market stabilization may well come from the size of the quota