1,721,152 research outputs found
Understanding the dynamics of violent political revolutions in an agent-based framework
No full textThis paper develops an agent-based computational model of violent political revolution in which a subjugated population of agents and an armed revolutionary organization try to overthrow a central authority and its loyal forces. The model replicates several patterns of rebellion consistent with the major historical revolutions and provides an explanation for the multiplicity of outcomes that can arise from an uprising. This last point is of particular interest if we consider the heterogeneity of political outcomes produced by the recent revolutionary episodes in the so-called Arab Spring
Can Social Media Substitute Revolutionary Leaders? An Agent-Based Demonstration
No full textThis paper demonstrates in an agent-based framework that, in the presence of social media, it is possible to observe a revolution without the need of a strong political leadership
Why Are Contemporary Political Revolutions Leaderless? An Agent-Based Explanation
No full textModern revolutions, like the recent uprisings in the so-called Arab Spring, seem to be organized by social network technologies and characterized by a lack of a strong political leadership. This feature is in sharp contrast with the previous historical revolutions, often shaped by charismatic figures. The present paper provides an explanation for this radical change into an agent-based framework: simulations show that, without the use of social media, influential leaders are necessary to obtain a huge mass mobilization whereas, in the presence of a social network, it is possible to accomplish this result without the need of a strong political leadership
Distribution Dynamics of Property Crime Rates in the United States
No full textUsing crime data for the 48 continental and conterminous US states and the distribution dynamics approach, this paper detects two distinct phases in the evolution of the property crime distribution: a period of strong convergence (1971-1980) is followed by a tendency towards divergence and bimodality (1981-2010). Moreover, the analysis reveals that differences in income per capita and police can explain the emergence of a bimodal shape in the distribution of property crime: in fact, after conditioning on these variables, the bimodality completely disappears. This empirical evidence is consistent with the predictions of a two-region model, that stresses the importance of income inequality in determining the dynamics of the property crime distribution
The external financial spillovers of CBDCs
No full textWe set up a DSGE model to study the macroeconomic consequences of a foreign central bank digital currency (CBDC) available to residents in a small open economy. We find that a gradual and permanent increase in the domestic households' preferences toward the foreign CBDC leads to a structural reduction in economic activity, especially if the CBDC is designed to be similar to domestic deposits. Imposing capital flow management measures on outflows, relaxing macroprudential policy, or selling foreign reserves can smooth the transition. A Taylor rule that targets PPI inflation is more effective in limiting the disruptive effects than a CPI targeting or an exchange rate peg. A central bank's liquidity facility available to commercial banks is able to avoid the long-run GDP loss, at the cost of a larger short-run consumption fall. We also show that an economy with a large stock of foreign CBDC is better shielded from exogenous increases in the interest rate on foreign debt, if the CBDC remuneration remains constant
Understanding the Dynamics of Violent Political Revolutions in an Agent-Based Framework
No full textThis paper develops an agent-based computational model of violent political revolutions in which a subjugated population of citizens and an armed revolutionary organisation attempt to overthrow a central authority and its loyal forces. The model replicates several patterns of rebellion consistent with major historical revolutions, and provides an explanation for the multiplicity of outcomes that can arise from an uprising. The relevance of the heterogeneity of scenarios predicted by the model can be understood by considering the recent experience of the Arab Spring involving several rebellions that arose in an apparently similar way, but resulted in completely different political outcomes: the successful revolution in Tunisia, the failed protests in Saudi Arabia and Bahrain, and civil war in Syria and Libya
Dynamin controls neuropeptide secretion by organizing dense-core vesicle fusion sites.
No full textSynaptic vesicles (SVs) release neurotransmitters at specialized active zones, but release sites and organizing principles for the other major secretory pathway, neuropeptide/neuromodulator release from dense-core vesicles (DCVs), remain elusive. Here, we identify dynamins, yeast Vps1 orthologs, as important DCV fusion site organizers in mammalian CNS neurons. Genetic or pharmacological inactivation of all three dynamins strongly impaired DCV exocytosis, while SV exocytosis remained unaffected. Wildtype dynamin restored normal exocytosis, but not GTPase-deficient or membrane-binding mutants that cause neurodevelopmental syndromes. During prolonged stimulation, repeated use of the same DCV fusion location was impaired in dynamin 1-3 triple knockout neurons. The syntaxin-1 staining efficiency, but not its expression level, was reduced. αSNAP expression restored this. We conclude that mammalian dynamins organize DCV fusion sites, downstream of αSNAP-mediated cis-SNARE disassembly, by regulating the equilibrium between fusogenic and non-fusogenic syntaxin-1 and promoting its availability to form trans-SNARE complexes that drive DCV exocytosis
Dynamin controls neuropeptide secretion by organizing dense-core vesicle fusion sites.
No full textSynaptic vesicles (SVs) release neurotransmitters at specialized active zones, but release sites and organizing principles for the other major secretory pathway, neuropeptide/neuromodulator release from dense-core vesicles (DCVs), remain elusive. Here, we identify dynamins, yeast Vps1 orthologs, as important DCV fusion site organizers in mammalian CNS neurons. Genetic or pharmacological inactivation of all three dynamins strongly impaired DCV exocytosis, while SV exocytosis remained unaffected. Wildtype dynamin restored normal exocytosis, but not GTPase-deficient or membrane-binding mutants that cause neurodevelopmental syndromes. During prolonged stimulation, repeated use of the same DCV fusion location was impaired in dynamin 1-3 triple knockout neurons. The syntaxin-1 staining efficiency, but not its expression level, was reduced. αSNAP expression restored this. We conclude that mammalian dynamins organize DCV fusion sites, downstream of αSNAP-mediated cis-SNARE disassembly, by regulating the equilibrium between fusogenic and non-fusogenic syntaxin-1 and promoting its availability to form trans-SNARE complexes that drive DCV exocytosis
WEARABLE VISION DEVICE
No full textThe present invention aims to provide alternative means for the diagnosis of the risk of developing mouth mucosa cancers by means of fluorescence, easy to use, simple, light and space-saving and diagnostic kits comprising the above- mentioned device
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