1,587 research outputs found

    A Model of Vertical Oligopolistic Competition

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    This paper develops a model of successive oligopolies with endogenous market entry, allowing for varying degrees of product differentiation and entry costs in both markets. Our analysis shows that the downstream conditions dominate the overall profitability of the two-tier structure while the upstream conditions mainly affect the distribution of profits. We compare the welfare effects of upstream versus downstream deregulation policies and show that the impact of deregulation may be overvalued when ignoring feedback effects from the other market. Furthermore, we analyze how different forms of vertical restraints influence the endogenous market structure and show when they are welfare enhancing

    Effect of side chains on the electronic and photovoltaic properties of diketopyrrolopyrrole-based molecular acceptors

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    Four molecular electron acceptors based on a common phthalimide end-capped diketopyrrolopyrrole pconjugated backbone, solubilized by different alkyl groups, have been synthesized. The influence of the nature and position of the solubilizing alkyl chains attached at the three constitutive blocks has been investigated. Results collected from UV-Vis absorption spectroscopy, cyclic voltammetry, solar cells fabrication and testing as well as atomic force microscopy show that the mode of substitution has negligible effect at the molecular level but strongly affects the material self-assembling properties, charge carrier transport and in turn, devices performances

    Proteomic analysis of chemosensory organs in the honey bee parasite Varroa destructor: a comprehensive examination of the potential carriers for semiochemicals

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    The mite Varroa destructor is the major parasite of the honey bee and is responsible for great economical losses. The biochemical tools used by Varroa to detect semiochemicals produced by the host are still largely unknown. We have performed proteomic analysis on chemosensory organs of this species in order to identify putative soluble carriers for pheromones and other olfactory cues emitted by the host. In particular, we have analysed forelegs, mouthparts (palps, chelicera and hypostome) and the second pair of legs (as control tissue) in reproductive and phoretic stages of the Varroa life cycle. We identified 958 Varroa proteins, most of them common to organs and stages. Sequence analysis shows that four proteins can be assigned to the odorant-binding protein (OBP)-like class, which bear some similarity to insect OBPs, but so far are only reported in some Chelicerata. In addition, we have detected the presence of two proteins belonging to the Niemann-Pick family, type C2 (NPC2), which have been suggested to act as semiochemical carriers. This work contributes to elucidating the chemical communication systems in Varroa with the aim of understanding how detection of semiochemicals has evolved in terrestrial non-hexapod Arthropoda. Data are available via ProteomeXchange with identifier PXD008679

    Social Media Technologies' Use for the Competitive Information and Knowledge Sharing, and Its Effects on Industrial SMEs' Innovation

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    The effective use of technologies supporting decision making is essential to companies? survival. Recent studies analyzed social media technologies (SMT) in the context of small- and medium-sized enterprises (SMEs), contributing to the discussion on SMT benefits from the marketing perspective. This article focuses on the effects of SMT use on innovation. Our findings provide empirical evidence on the positive effects of SMT use for acquiring external information and for sharing knowledge and innovation performance

    Does Gambling-Focused Treatment Affect Mental Health and Quality of Life? A Systematic Review and Meta-Analysis

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    Abstract: Cognitive-behavioral (CB) techniques have received substantial empirical support for reducing gambling disorder symptoms and behavior. What has not been established is whether gambling-focused treatment reduces psychological problems and improves quality of life. Individuals experiencing gambling-related harms report that sustained recovery involves changing both gambling behaviors and psychological problems and building a meaningful life. The current systematic review and meta-analysis aimed to examine the effect of CB techniques targeting gambling harms on nontargeted outcomes such as psychological problems and quality of life. Following PRISMA guidelines, a systematic article search was conducted to locate published studies of randomized controlled trials of CB techniques targeting gambling harms and reporting nontargeted outcomes. Random effects meta-analysis was used to quantify the effect of CB techniques on nontargeted outcomes. Ten studies representing 797 participants were included. Eight studies reported the effect of CB techniques on anxiety, 8 on depression, 3 on substance use, and 7 on quality of life. CB techniques significantly reduced anxiety (g = -0.44), depression (g = -0.35), gambling frequency (g = -0.30), and gambling intensity (g = -0.36) at posttreatment, but not substance use. CB techniques also significantly improved quality of life (g = 0.39) at posttreatment. Implications: The targeted reduction of gambling harms may serve as a mechanism of change for reducing psychological problems and improving quality of life. Future studies should employ longitudinal designs to understand the associations between gambling reductions and changes in nontargeted recovery outcomes over time

    Does \u2018bigger\u2019mean \u2018better\u2019? Pitfalls and shortcuts associated with big data for social research

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    \u2018Big data is here to stay.\u2019 This key statement has a double value: is an assumption as well as the reason why a theoretical reflection is needed. Furthermore, Big data is something that is gaining visibility and success in social sciences even, overcoming the division between humanities and computer sciences. In this contribution some considerations on the presence and the certain persistence of Big data as a socio-technical assemblage will be outlined. Therefore, the intriguing opportunities for social research linked to such interaction between practices and technological development will be developed. However, despite a promissory rhetoric, fostered by several scholars since the birth of Big data as a labelled concept, some risks are just around the corner. The claims for the methodological power of bigger and bigger datasets, as well as increasing speed in analysis and data collection, are creating a real hype in social research. Peculiar attention is needed in order to avoid some pitfalls. These risks will be analysed for what concerns the validity of the research results \u2018obtained through Big data. After a pars distruens, this contribution will conclude with a pars construens; assuming the previous critiques, a mixed methods research design approach will be described as a general proposal with the objective of stimulating a debate on the integration of Big data in complex research projecting

    ‘We need to get together and make ourselves heard’: everyday online spaces as incubators of political action

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    This article examines to what extent, and how, people engaging in political talk within ‘non-political’ discussion forums – online lifestyle communities – leads to political (or personal) action or calls-to-action. The analysis is framed in the context of wider questions of citizenship, civic engagement and political mobilization. To capture everyday political talk amongst citizens requires us to move beyond the now widely analysed online spaces of formal politics. Instead, we focus on online third spaces concerning lifestyle issues such as parenting, personal finance and popular culture. Drawing on a content analysis of three popular UK-based discussion forums over the course of five years (2010–2014), we found that (for two of the three cases) such spaces were more than just talking shops. Rather they were spaces where political actions not only emerged, but where they seemed to be cultivated. Discussions embedded in the personal lives of participants often developed – through talk – into political actions aimed at government (or other) authorities. The article sheds light on the contributing factors and processes that (potentially) trigger and foster action emerging from political talk and provides insight into the mobilization potential of third spaces

    Consumer Surplus in Online Auctions

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