Trust and cooperation in buyer–seller relationships and networks. The co-evolution of structural balance and trust in iterated PD games

Our study has two aims: to elaborate theoretical frameworks and introduce social mechanisms of spontaneous co-operation in repeated buyer-seller relationships and to formulate hypotheses which can be empirically tested. The basis of our chain of ideas is the simple two-person Prisoner’s Dilemma game. On the one hand, its repeated variation can be applicable for the distinction of the analytical types of trust (iteration trust, strategy trust) in co-operations. On the other hand, it provides a chance to reveal those dyadic sympathy-antipathy relations, which make us understand the evolution of trust. Then we introduce the analysis of the more complicated (more than two-person) buyer-seller relationship. Firstly, we outline the possible role of the structural balancing mechanisms in forming trust in three-person buyer-seller relationships. Secondly, we put forward hypotheses to explain complex buyer-seller networks. In our research project we try to theoretically combine some of the simple concepts of game theory with certain ideas of the social-structural balance theory. Finally, it is followed by a short summary

A PPAR-gamma, egy lipidek által aktivált transzkripciós faktor aktivitásának szabályozása a makrofágok különböző állapotaiban = Regulation of the activity of a lipid-activated transcription factor, PPAR-gamma in macrophages

A Peroxisome Proliferator-activated Receptor y (PPARy) egy lipidek által aktivált transzkripciós faktor, mely a lipidanyagcsere és a gyulladás szabályozásával olyan folyamatokban vesz részt, mint az érelmeszesedés és diabétesz. A PPARy aktivátorai több szinten képesek a gyulladás gátlására. Jelen pályázat célja az volt, hogy tanulmányozzuk a gyulladásos folyamatok PPARy aktivitására kifejtett hatását, megvizsgáljuk, hogy a gyulladásos mediátorok hogyan kommunikálnak a PPARy-val és megfejtsük ezeknek folyamatoknak a molekuláris mechanizmusát. Azt találtuk, hogy a gyulladásos molekulák befolyásolják a PPARy működését. Proinflammatórikus molekulák gátolják, míg az interleukin-4 (IL-4) fokozza a receptor működését makrofágokban és dendritikus sejtekben. Az IL-4 szignálútvonal bekapcsolása egy újonnan feltárt mechanizmussal, a Signal Transducer and Activators of Transcription 6 (STAT6) és a PPARg interakciója révén erősíti a receptor válaszait a célgének promóterén. Ennek eredményeképpen az IL-4 emeli a PPARg által szabályozott gének számát és fokozza az egyes gének esetében azok transzkripcióját. Ily módon a PPARg egy pozitív transzkripciós faktorként működhet a makrofágokban is. Eredményeink szerint létezik egy új mechanizmus, ahogy az immunrendszer sejtspecifikusan képes szabályozni egy magreceptor működését. Mindez felhívja a figyelmet a sejtek gyulladásos állapota és a lipidanyagcsere kapcsolatára olyan folyamatokban, mint pl. az érelmeszesedés. | Peroxisome Proliferator-activated Receptor y(PPARy) is a lipid-activated transcription factor that regulates lipid metabolism and inflammation, key processes in atherosclerosis and diabetes. PPARy agonists are known to regulate inflammation on multiple levels. The goal of this grant was to study how the inflammatory milieu regulates the activity of PPARy, analyze the crosstalk between inflammatory reactions and PPARy and to find the molecular mechanism how mediators of the immune system influence the receptor activity. We demonstrated that inflammatory molecules interfere with PPARg signaling. Proinflammatory molecules inhibit, while interleukin-4 (IL-4) stimulate PPARy in macrophages and dendritic cells (DCs). Activation of IL-4 signaling augments PPARg activity through a novel interaction between PPARg and Signal Transducer and Activators of Transcription 6 on the promoter of PPAR? target genes, like FABP4. As a consequence, IL-4 strongly enhances PPARy response and acts as a licensing factor by increasing the number of genes regulated and also the magnitude of the responses. Through target gene induction PPARy can be designated a positive regulator of macrophage gene expression. These findings introduce a new mechanism how inflammatory molecules modulate the activity of a nuclear receptor via cell-type specific factors and highlight the importance of the inflammatory status of cells in lipid metabolism and atherosclerosis

Combinatorial aspects of extensions of Kronecker modules

Let kK be the path algebra of the Kronecker quiver and consider the category of finite dimensional right modules over kK (called Kronecker modules). We prove that extensions of Kronecker modules are field independent up to Segre classes, so they can be described purely combinatorially. We use in the proof explicit descriptions of particular extensions and a variant of the well known Green formula for Ringel-Hall numbers, valid over arbitrary fields. We end the paper with some results on extensions of preinjective Kronecker modules, involving the dominance ordering from partition combinatorics and its various generalizations.Comment: 11 page

Physicists, stamp collectors, human mobility forecasters

One of the two reviewers studied in high school to be a physicist. In the end, he became something else, but he never lost his awe of physics. The other reviewer never intended to become a physicist, but he sometimes asks himself why he didn’t become one. Today, they are both sociologists who practice their science on an action theory basis and believe that regularities exist in the world of social actions which can be perceived, understood, explained – and even used for making predictions

Preinjective subfactors of preinjective Kronecker modules

Using a representation theoretical approach we give an explicit numerical characterization in terms of Kronecker invariants of the subfactor relation between two preinjective (and dually preprojective) Kronecker modules, describing explicitly a so called linking module as well. Preinjective (preprojective) Kronecker modules correspond to matrix pencils having only minimal indices for columns (respectively for rows). Thus our result gives a solution to the subpencil problem in these cases (including the completion), moreover the required computations are straightforward and can be carried out easily (both for checking the subpencil relation and constructing the completion pencils based on the linking module). We showcase our method by carrying out the computations on an explicit example.Comment: 13 page

Double or quits: should money found be risked?

This article examines social attitudes towards risk-preference and risk-aversion. First, we briefly discuss the theoretical approach to the analysis of risk-preference and risk-aversion that was developed within rational choice theory. Next, we present an approach to operationalise risk-preference using survey data. Our measurement of attitudes towards risk follows the usual strategy: respondents are asked to choose between a small amount of money they get for sure, and a large but risky amount. Drawing on the theoretical models and earlier empirical research, we formulate hypotheses about the social factors that have an impact on actual decision making in the situations under study. The hypotheses are tested using survey data. The article ends with a brief discussion. The novelty of our paper is that – to the best of our knowledge – neither previous Hungarian nor international research has attempted to examine attitudes towards risk using data from large-scale surveys

How can economic sociology help business relationship management?

Purpose – By analyzing organizations as social actors and business relationships as social relationships, sociology can improve business relationship management. This paper aims to explore the issues involved. Design/methodology/approach – A business relationship is an interactive exchange between two organizations embedded in a network of business connections. The paper reviews theories of social actions and social actors and the concepts of economic field and embeddedness to illustrate some social dimensions of business relationships. Findings – Social action and social actor theories emphasize that co-operation is always encumbered with conflicts, that consciousness about the relationship is fundamental for both strongly and weakly structured actors, and that actors (people involved in a business relationship) always have some freedom of manoeuvre. The concept of economic field underscores the specificity of each business relationship and the critical need for concrete analysis. The concept of embeddedness highlights that no business relationship is possible without personal bonds. Research limitations/implications – These are the first results of a deeper and broader research directed towards a conceptual model of business relationship management. Practical implications – The paper can help managers to analyze more deeply the social dimensions of business relations with both suppliers and buyers. Consciousness, the ongoing presence of conflicts, the unavoidable role of personal bonds, and interactivity are always relevant in business relationship management. Originality/value – The paper integrates sociological and business marketing approaches. It applies essential sociological theories and concepts to business relationship management

A stroncium-ranelát helye az osteoporosis kezelésében

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Társadalmi részvétel Magyarországon. Siker vagy kudarc?

A társadalmi részvétel változatos formái egyre népszerűbbnek számítanak Magyarországon, ezek közül is talán a közmeghallgatások (vagy lakossági fórumok) és a helyi népszavazások intézménye a legtöbbször alkalmazott technika. Az állampolgárok bevonására építő folyamatok értékelése egyrészt azért fontos, hogy meggyőződjünk arról, ezek a részvételi formák valóban beváltják-e a hozzájuk fűzött reményeket, másrészt hogy feltárjuk, az egyes döntési szituációkban mely módszerek mellett érdemes letenni a voksunkat. A szerző a közmeghallgatások és a helyi népszavazások mellett az állampolgári ellenőrző csoportok működését vizsgálja a közelmúltban lezajlott cementipari gyártelepítések és technológiaváltások kapcsán