Setting the Agenda: Different strategies of a Mass Media in a model of cultural dissemination

Day by day, people exchange opinions about a given new with relatives, friends, and coworkers. In most cases, they get informed about a given issue by reading newspapers, listening to the radio, or watching TV, i.e., through a Mass Media (MM). However, the importance of a given new can be stimulated by the Media by assigning newspaper's pages or time in TV programs. In this sense, we say that the Media has the power to "set the agenda", i.e., it decides which new is important and which is not. On the other hand, the Media can know people's concerns through, for instance, websites or blogs where they express their opinions, and then it can use this information in order to be more appealing to an increasing number of people. In this work, we study different scenarios in an agent-based model of cultural dissemination, in which a given Mass Media has a specific purpose: To set a particular topic of discussion and impose its point of view to as many social agents as it can. We model this by making the Media has a fixed feature, representing its point of view in the topic of discussion, while it tries to attract new consumers, by taking advantage of feedback mechanisms, represented by adaptive features. We explore different strategies that the Media can adopt in order to increase the affinity with potential consumers and then the probability to be successful in imposing this particular topic.Comment: 23 pages, 7 figure

Structural changes in exchange rate regimes in Brazil

Following a dramatic breakdown of a managed floating regime, Brazil adopted a framework for policy consisting of inflation targeting and floating exchange rates. The country's commitment to this arrangement, however, is often put to dispute. In this paper we revisit the issue of whether Brazil has truly accepted to let its currency float, taking use of cross-currency linear regression models complemented by inferential techniques for evaluating the stability of exchange rate regimes. The results found suggest that Brazil does seem to have shifted towards greater exchange rate flexibility after the abandonment of its dollar-peg. However, after the adoption of inflation targeting the degree of exchange rate flexibility seems to have reduced a little.Structural changes; exchange rate regimes; emerging markets.

Assessing students’ beliefs, emotions and causal attribution: Validation of ‘Learning Conception Questionnaire’

Students’ conceptions of learning represent an influential factor for learning, yet the few existing studies used measures with limited validity and lacked to provide a model for middle school students. This research aimed to provide a preliminary validation of ‘Learning Conception Questionnaire’ (LCQ) by Liverta Sempio and Marchetti (2001) aimed to measure conceptions of learning in a holistic way by including belief, academic emotion, and causal attributions. In the current study, the factor structure was tested in a sample of 212 middle school students. Exploratory factor analysis (EFAs) and Confirmatory factor analysis (CFAs) showed that the factor structure of the comprehensive measure of conceptions of learning used could be described across three domains (Belief: Comparative Fit Index [CFI] = .98, Standardised Root Mean Square Residual [SRMR] = .06; Emotions: CFI = .89, SRMR = .07; Causal attribution: CFI = .92, SRMR = .06), with significant relationships. Implications and future ways of research were discussed.Keywords: academic emotion; belief; causal attribution; statistical validation; students’ conceptions of learnin

Factores que impiden aplicar una gestión de riesgos en la Empresa Constructora HISAC Contratistas S.R.L. - Trujillo

La presente tesis tiene como propósito identificar los factores negativos que impiden implementar una gestión de riesgos en la empresa constructora HISAC CONTRATISTAS S.R.L. De los cuales se escogió un proyecto, el cual será evaluado para poder identificar los factores negativos, en la implementación de una gestión de riesgos. Sé procederá a encuestar a los principales responsables de la ejecución de los proyectos seleccionados a evaluar, con el fin de identificar los factores negativos que impiden llevar a cabo una correcta implementación de una gestión de riesgos; es decir, se llevó a cabo la elaboración de una encuesta, la cual nos permitirá obtener datos reales, acerca del nivel de participación, conocimiento y compromiso; para llevar a cabo con éxito este proyecto. La propuesta más conveniente, debe ser puesta en marcha lo más pronto posible; sin perjudicar la economía de la empresa constructora HISAC CONTRATISTAS S.R.L; la cual debe ser fuente de evaluación de los proyectos a ejecutar en un futuro. Las recomendaciones y conclusiones que se elaborarán, van a permitir a otras empresas constructoras que trabajen con el estado, en poder identificar y poner en marcha una correcta gestión de riesgos.This thesis aims to identify the negative factors that prevent implementing a management of risks in the construction company HISAC CONTRATISTAS S.R.L. Of which was chosen a project, which will be evaluated to identify the negative factors in the implementation of risk management. I know will be interviewing those chiefly responsible for the implementation of the selected projects to evaluate, in order to identify negative factors that impede to carry out a correct implementation of a risk management; i.e., the elaboration of a survey, which will allow us to get real data, about the level of participation was conducted, knowledge and commitment; in order to successfully complete this project. The most suitable proposal, should be launched as soon as possible; without harming the economy of the construction company HISAC CONSTRATISTAS S.R.L; which should be source of evaluation of projects to implement in the future. The recommendations and conclusions that will be developed, they will allow other construction companies to work with the State, to identify and implement proper risk management.Tesi

Fuzzy DEA models for sports data analysis: The evaluation of the relative performances of professional (virtual) football teams

The measurement of sports performances both of individual athletes and of an entire sports team, now highly widespread thanks to the enormous availability of sports data, is a crucial moment for professional sports clubs as the their survival is increasingly linked both to the results in the field obtained by its athletes and/or the team/s and to the achievement of many other sporting objectives. We here propose the use of the DEA methodology adapted to fuzzy logic to measure relative performances in the presence of uncertainty of a virtual sample of professional football teams along two dimensions: efficiency and effectiveness. The results obtained are especially interesting from the point of view of policy indications for the organization and management of the teams on the soccer pitch. The work then develops a second stage analysis structured in order to investigate on the one hand with the help of an econometric model the influence that a set of external factors can have on the performances and on the other, by calculating the gini coefficient, evaluates for various attitudes on the part of managers on uncertainty the degree of inequality in the distribution of sports performances of the groups that have participated in an ideal tournament. In conclusion, the work aims to develop, to our knowledge, an innovative and original way for the reference literature, a framework for analyzing sports data (and in particular for professional football clubs) in order to provide policy indications for improve their sports performances

Performances management when modelling internal structure

The performances management is a key issue for public as well as private organizations. The core of the performances management in the DEA context are essentially the relative efficiency measurement for organizations considered as a “black box” that use inputs to produce two or more outputs. In reality, organizations/ production process are comprised of a number of divisions/stages which performs different functions/tasks interacting among them. For these reasons modelling internal structures of organizations/production process allow to discover the inefficiency of individual divisions/stages. In this paper we estimate the relative efficiency of a production process once modelling its internal structure with a network structure of three divisions/stages interrelated among them. To outline the differences in the performances management in the two cases (“black box” vs network structure) we compare they empirical cumulative distribution functions

Model and measure the relative efficiency of a four-stage production process. An NDEA multiplier relational model under different systems of resource distribution preferences between sub-processes

Measuring the relative efficiency of a production process with the DEA considers the production process as a “black box” that uses inputs to transform them into outputs. In reality, many production processes are carried out by carrying out several interconnected activities that are usually grouped into phases that are in turn interconnected. For this reason, measuring the relative efficiency of a production process within the DEA technique requires shaping it as a network system (in others words to consider the production process as interconnected sub-process). In the case of network systems, the NDEA approach has developed many models to measure their relative efficiency: independent models, connected models and relational models. In particular, the relational model allows to measure at the same time both the efficiency of the system and the efficiency of the sub-process once the operations between the latter have been considered. In our opinion, many real production processes can be modelled as a network of four sub-processes that are differently interconnected with each other. In this paper we will model a production process as a network of four sub-processes with shared variables and fixed preferences about the allocation of system resources between them. To measure the relative efficiency of the process and its parts we will develop an input-oriented NDEA model in the multiplier version. To solve the model we will use virtual data under several resources allocation preference’s structure. Then we will conclude that 1) a production process with four interconnected sub-processes can represent a large number of real production processes, so the NDEA model developed here can potentially be used for many applications, 2) the resource allocation preference system inter-sub-process influences the measurement of relative efficiency

Model and measure the relative efficiency of a four-stage production process. An NDEA multiplier relational model under different systems of resource distribution preferences between sub-processes

Measuring the relative efficiency of a production process with the DEA considers the production process as a “black box” that uses inputs to transform them into outputs. In reality, many production processes are carried out by carrying out several interconnected activities that are usually grouped into phases that are in turn interconnected. For this reason, measuring the relative efficiency of a production process within the DEA technique requires shaping it as a network system (in others words to consider the production process as interconnected sub-process). In the case of network systems, the NDEA approach has developed many models to measure their relative efficiency: independent models, connected models and relational models. In particular, the relational model allows to measure at the same time both the efficiency of the system and the efficiency of the sub-process once the operations between the latter have been considered. In our opinion, many real production processes can be modelled as a network of four sub-processes that are differently interconnected with each other. In this paper we will model a production process as a network of four sub-processes with shared variables and fixed preferences about the allocation of system resources between them. To measure the relative efficiency of the process and its parts we will develop an input-oriented NDEA model in the multiplier version. To solve the model we will use virtual data under several resources allocation preference’s structure. Then we will conclude that 1) a production process with four interconnected sub-processes can represent a large number of real production processes, so the NDEA model developed here can potentially be used for many applications, 2) the resource allocation preference system inter-sub-process influences the measurement of relative efficiency

Ruolo di LXR nella modulazione del danno epatico mediato dall'attivazione dell'asse fegato-intestino

La fibrosi epatica rappresenta la risposta del fegato al danno epatico cronico. Tuttavia, l’assenza di un chiaro modello di patogenesi si riflette nella mancanza di terapie efficaci. I recettori LXR (Liver X Receptors) regolano il metabolismo epatico di acidi grassi e colesterolo, mentre a livello intestinale causano un aumento del reverse cholesterol transport (RCT) che causa un incremento delle HDL circolanti. Per valutare gli effetti dell’attivazione intestinale di LXRα nello sviluppo della fibrosi epatica associata ad un danno cronico indotto, abbiamo trattato per due mesi con Tetracloruro di Carbonio (CCl4) topi maschi FVB/N con attivazione intestinale costitutiva di LXRα (iVP16LXRα) e i rispettivi controlli. Abbiamo osservato come l’espressione genica delle citochine pro infiammatorie IL6 e TNFα e del fattore di trascrizione NFkB risultasse ridotta nei topi iVP16LXRα trattati con CCl4. Dati di immunoistochimica per il marker F4/80 indicano un minor infiltrato macrofagico nel fegato dei topi iVP16LXRα a cui si associa una diminuzione della sintesi e della deposizione di collagene. Inoltre, l’aumento del RCT nei iVP16LXRα, dimostrata dall’overespressione intestinale del trasportatore ABCA1 e dell’Apolipoproteina A1, correla con l’aumento delle HDL misurato nell’analisi del profilo lipoproteico. Infine, non si è riscontrata de novo lipogenesi né de novo sintesi del colesterolo a livello epatico nei topi iVP16LXRα, confermata anche da un inferiore il contenuto epatico di trigliceridi e colesterolo. Il nostro studio ha quindi evidenziato come l’attivazione intestinale di LXRα riduca il danno epatico, tramite l’aumento dei livelli di HDL antiinfiammatorie che svolgono un ruolo positivo nel contrastare l’insorgenza di fibrosi epatica. Tali dati saranno quindi utili per sviluppare un nuovo approccio terapeutico finalizzato a ridurre la fibrosi del fegato evitando gli effetti collaterali associati all’attivazione sistemica di LXR.Hepatic fibrosis represents the wound-healing response of the liver to chronic injury. The pathogenesis of liver fibrosis is not fully understood, leading to a lack in effective therapies. Liver X receptors (LXR α/β) are important regulators of lipid metabolism; in the liver regulates cholesterol and fatty acid metabolism, whereas in the intestine are implicated in reverse cholesterol transport (RCT) pathway leading to high levels of the antinflammatory HDL. In order to evaluate the effect of the selective intestinal LXRα activation on the development of hepatic fibrosis associated to chronic liver injury, we treated mice with intestinal constitutive LXRα activation (iVP16LXRα) and their control (iVP16) with i.p. injection of Carbon Tetrachloride for 2 months. We observed a reduction of pro-inflammatory cytokines IL-6, TNFα, and of the transcription factor NF-Kb in iVP16LXRα mice. The lower macrophage infiltration displayed by immunohystochemistry for the marker F4/80 in iVP16LXRα liver, correlates with a reduction of collagen synthesis and deposition, determined by collagen1α and TGFβ mRNA expression and by Sirius Red morphometry. RCT was proved by measuring intestinal gene expression of Abca1 and ApoA1 that was increased in iVP16LXα, in line with the elevation of plasmatic HDL concentration. Furthermore, intestinal LXRα activation is not associated to hepatic de novo lipogenesis and de novo cholesterol synthesis as shown by gene expression of the relatives gene target, and decreased triglyceride and cholesterol content. Thus, specific intestinal LXRα activation reduces liver injury by increasing the level of the antinflammatory HDL cholesterol, resulting in a decreased hepatic fibrosis. Selective intestinal activation of LXRα might be considered as a new therapeutic approach to reduce liver fibrosis avoiding the occurrence of hepatic steatosis as a side effects associated to systemic LXR induction

Performances management when modelling internal structure

The performances management is a key issue for public as well as private organizations. The core of the performances management in the DEA context are essentially the relative efficiency measurement for organizations considered as a “black box” that use inputs to produce two or more outputs. In reality, organizations/ production process are comprised of a number of divisions/stages which performs different functions/tasks interacting among them. For these reasons modelling internal structures of organizations/production process allow to discover the inefficiency of individual divisions/stages. In this paper we estimate the relative efficiency of a production process once modelling its internal structure with a network structure of three divisions/stages interrelated among them. To outline the differences in the performances management in the two cases (“black box” vs network structure) we compare they empirical cumulative distribution functions