Baryon Structure

A review of the theoretical activity in Italy in the research field of Hadronic Physics is given. Specific focus is put on phenomenological models based on the effective degrees of freedom of constituent quarks, on parton distributions in hard processes in the Bjorken limit and on the possibility of linking the two concepts via evolution equations. A brief introduction is given also about the socalled generalized parton distributions.Comment: 20 pages, no figures, invited general report at the "IX Convegno su Problemi di Fisica Nucleare e Teorica", Cortona, Oct. 9-12, 2002 (Italy), to appear in World Scientific Proceeding

Exclusive charge exchange reaction pD->n(pp) within the Bethe-Salpeter formalism

The exclusive charge exchange reaction pD->n(pp) at intermediate and high energies is studied within the Bethe-Salpeter formalism. The final state interaction in the detected pp pair at nearly zero excitation energy is described by the 1S0 component of the Bethe-Salpeter amplitude. Results of numerical calculations of polarization observables and differential cross-section persuade that, as in the non-relativistic case, this reaction (i) can be utilized as a ``relativistic deuteron polarimeter'' and (ii) delivers further information about the elementary nucleon-nucleon charge-exchange amplitude.Comment: 38 pages, 10 eps-figure

Income support systems for the unemployed : issues and options

The report reviews the performance of various income support systems for the unemployed, and provides guidelines for developing and transition economies. It finds that: a) Unemployment insurance enables a high degree of consumption smoothing, performs well under various types of shocks, and acts as an automatic stabilizer. But it also creates reemployment disincentives, and wage pressure which increase the equilibrium unemployment rate, contributing to persistent unemployment. b) Unemployment assistance, while enabling more effective targeting, may not bring savings in comparison to unemployment insurance, and may well prove fiscally unsustainable. c) Unemployment insurance savings accounts, internalize the costs of unemployment benefits, and thus avoid the moral hazard inherent in traditional unemployment insurance, given the weak monitoring capacity of developing countries, an important advantage. d) Public works program is effective in reaching the poor, can attract informal sector workers, and provides flexible, fast responses to shocks. Despite its high non-wage costs, and possible stigmatization of participants, it is found suitable for developing countries, particularly as a complementary program. e) Severance pay offers few advantages - it adversely affects efficiency, produces high litigation costs, and offers limited risk-pooling.Environmental Economics&Policies,Rural Poverty Reduction,Safety Nets and Transfers,Services&Transfers to Poor,Health Economics&Finance

Subtyping with Generics: A Unified Approach

Reusable software increases programmers\u27 productivity and reduces repetitive code and software bugs. Variance is a key programming language mechanism for writing reusable software. Variance is concerned with the interplay of parametric polymorphism (i.e., templates, generics) and subtype (inclusion) polymorphism. Parametric polymorphism enables programmers to write abstract types and is known to enhance the readability, maintainability, and reliability of programs. Subtyping promotes software reuse by allowing code to be applied to a larger set of terms. Integrating parametric and subtype polymorphism while maintaining type safety is a difficult problem. Existing variance mechanisms enable greater subtyping between parametric types, but they suffer from severe deficiencies. They are unable to express several common type abstractions. They can cause a proliferation of types and redundant code. They are difficult for programmers to use due to its inherent complexity. This dissertation aims to improve variance mechanisms in programming languages supporting parametric polymorphism. To address the shortcomings of current mechanisms, I will combine two popular approaches, definition-site variance and use-site variance, in a single programming language. I have developed formal languages or calculi for reasoning about variance. The calculi are example languages supporting both notions of definition-site and use-site variance. They enable stating precise properties that can be proved rigorously. The VarLang calculus demonstrates fundamental issues in variance from a language neutral perspective. The VarJ calculus illustrates realistic complications by modeling a mainstream programming language, Java. VarJ not only supports both notions of use-site and definition-site variance but also language features with complex interactions with variance such as F-bounded polymorphism and wildcard capture. A mapping from Java to VarLang was implemented in software that infers definition-site variance for Java. Large, standard Java libraries (e.g. Oracle\u27s JDK 1.6) were analyzed using the software to compute metrics measuring the benefits of adding definition-site variance to Java, which only supports use-site variance. Applying this technique to six Java generic libraries shows that 21-47% (depending on the library) of generic definitions are inferred to have single-variance; 7-29% of method signatures can be relaxed through this inference, and up to 100% of existing wildcard annotations are unnecessary and can be elided. Although the VarJ calculus proposes how to extend Java with definition-site variance, no mainstream language currently supports both definition-site and use-site variance. To assist programmers with utilizing both notions with existing technology, I developed a refactoring tool that refactors Java code by inferring definition-site variance and adding wildcard annotations. This tool is practical and immediately applicable: It assumes no changes to the Java type system, while taking into account all its intricacies. This system allows users to select declarations (variables, method parameters, return types, etc.) to generalize and considers declarations not declared in available source code. I evaluated our technique on six Java generic libraries. I found that 34% of available declarations of variant type signatures can be generalized-i.e., relaxed with more general wildcard types. On average, 146 other declarations need to be updated when a declaration is generalized, showing that this refactoring would be too tedious and error-prone to perform manually. The result of applying this refactoring is a more general interface that supports greater software reuse

Quark-Antiquark Bound States in the Relativistic Spectator Formalism

The quark-antiquark bound states are discussed using the relativistic spectator (Gross) equations. A relativistic covariant framework for analyzing confined bound states is developed. The relativistic linear potential developed in an earlier work is proven to give vanishing meson$\to$ $q+\bar{q}$ decay amplitudes, as required by confinement. The regularization of the singularities in the linear potential that are associated with nonzero energy transfers (i.e. $q^2=0,q^{\mu}\neq0$) is improved. Quark mass functions that build chiral symmetry into the theory and explain the connection between the current quark and constituent quark masses are introduced. The formalism is applied to the description of pions and kaons with reasonable results.Comment: 31 pages, 16 figure

International Journal of Applied Behavioral Sciences (IJABS)volume 7number 3Summer2020. Journals. smbu.ac.ir/ijabs 47 Effect of Cognitive-Behavioral Therapy (CBT) and Transcranial Direct Current Stimulation (tDCS) on Body Mass Index and Self-Control in Ov

Introduction: Considering the growing trend of overweight and its risk, it is necessary to find useful solutions for weight loss. Usually overweight people are involved in several treatment programs that have decent short-term effects, but the symptoms might be relapsed in long term. The purpose of this study was to compare the effectiveness of Cognitive-Behavioral Therapy (CBT) and transcranial Direct Current Stimulation (tDCS) on reducing body mass index and increase self-control in overweight women.Methods: This is a quasi-experimental study with pretest- posttest design and follow-up. The statistical population of this study included all overweight women referring to the Nutrition Clinic of Shahid Beheshti University of Medical Sciences. The sample consisted of 30 females selected by purposeful sampling method and were randomly assigned to two experimental groups. In this study, BMI was used to assess overweight and Tangney self-control scale was used for self-control.Results: The findings indicated that the self-control in the participants in the cognitive-behavioral group were more improved in comparison to transcranial Direct Current Stimulation group (p,0.05), while tDCS was more effective than CBT on improving body mass index.Conclusion: In general, cognitive-behavioral therapy and transcranial Direct Current Stimulation with effect on the area of the brain that is associate with control perception lead to increased self-control, decreased craving and BMI