7,793 research outputs found
Intergenerational Fiscal Constitutions: How to Protect Future Generations Using Land Taxes and Federalism
This paper studies how to design a fiscal constitution that, by capitalizing intergenerational spillovers into land values, is able to protect future generations from expropriation and to generate optimal investment in intergenerational public goods. In particular, we study how to accomplish these goals by changing two dimensions of the fiscal constitution: (1) the level of government to which different types of intergenerational public goods are assigned, and (2) the tax base of the different jurisdictions. We show that the instruments required to generate capitalization of the intergenerational spillovers depend on the type of the spillover. Land taxation is the essential instrument for policies that mostly generate fiscal spillovers, such as debt and public infrastructure. By contrast, interjurisdictional competition is the essential instrument for policies that mostly generate direct spillovers, such as irreversible environmental damages. Furthermore, we show that it is possible to design a fiscal constitution that generates full capitalization of fiscal spillovers, but in general, not one that generates full capitalization of direct spillovers.
Appetitive and Aversive Goal Values Are Encoded in the Medial Orbitofrontal Cortex at the Time of Decision Making
An essential feature of choice is the assignment of goal values (GVs) to the different options under consideration at the time of decision making. This computation is done when choosing among appetitive and aversive items. Several groups have studied the location of GV computations for appetitive stimuli, but the problem of valuation in aversive contexts at the time of decision making has been ignored. Thus, although dissociations between appetitive and aversive components of value signals have been shown in other domains such as anticipatory and outcome values, it is not known whether appetitive and aversive GVs are computed in similar brain regions or in separate ones. We investigated this question using two different functional magnetic resonance imaging studies while human subjects placed real bids in an economic auction for the right to eat/avoid eating liked/disliked foods. We found that activity in a common area of the medial orbitofrontal cortex and the dorsolateral prefrontal cortex correlated with both appetitive and aversive GVs. These findings suggest that these regions might form part of a common network
The Decision Value Computations in the vmPFC and Striatum Use a Relative Value Code That is Guided by Visual Attention
There is a growing consensus in behavioral neuroscience that the brain makes simple choices by first assigning a value to the options under consideration and then comparing them. Two important open questions are whether the brain encodes absolute or relative value signals, and what role attention might play in these computations.Weinvestigated these questions using a human fMRI experiment with
a binary choice task in which the fixations to both stimuli were exogenously manipulated to control for the role of visual attention in the valuation computation. We found that the ventromedial prefrontal cortex and the ventral striatum encoded fixation-dependent relative value signals: activity in these areas correlated with the difference in value between the attended and the unattended items. These attention-modulated relative value signals might serve as the input of a comparator system that is used to make a choice
Bottom production in Photon and Pomeron -- induced interactions at the LHC
In this paper we present a detailed comparison of the bottom production in
gluon -- gluon, photon -- gluon, photon -- photon, pomeron -- gluon, pomeron --
pomeron and pomeron -- photon interactions at the LHC. The transverse momentum,
pseudo -- rapidity and dependencies of the cross sections are calculated
at LHC energy using the Forward Physics Monte Carlo (FPMC), which allows to
obtain realistic predictions for the bottom production with one or two leading
intact protons. Moreover, predictions for the the kinematical range probed by
the LHCb Collaboration are also presented. Our results indicate that the
analysis of the single diffractive events is feasible using the Run I LHCb
data.Comment: 8 pages, 3 figures, 1 table. Version published in Physical Review
Evidence for a Common Representation of Decision Values for Dissimilar Goods in Human Ventromedial Prefrontal Cortex
To make economic choices between goods, the brain needs to compute representations of their values. A great deal of research has been performed to determine the neural correlates of value representations in the human brain. However, it is still unknown whether there exists a region of the brain that commonly encodes decision values for different types of goods, or if, in contrast, the values of different types of goods are represented in distinct brain regions. We addressed this question by scanning subjects with functional magnetic resonance imaging while they made real purchasing decisions among different categories of goods (food, nonfood consumables, and monetary gambles). We found activity in a key brain region previously implicated in encoding goal-values: the ventromedial prefrontal cortex (vmPFC) was correlated with the subjects' value for each category of good. Moreover, we found a single area in vmPFC to be correlated with the subjects' valuations for all categories of goods. Our results provide evidence that the brain encodes a "common currency" that allows for a shared valuation for different categories of goods
The Neural Mechanisms Underlying the Influence of Pavlovian Cues on Human Decision Making
In outcome-specific transfer, pavlovian cues that are predictive of specific outcomes bias action choice toward actions associated with those outcomes. This transfer occurs despite no explicit training of the instrumental actions in the presence of pavlovian cues. The neural substrates of this effect in humans are unknown. To address this, we scanned 23 human subjects with functional magnetic resonance imaging while they made choices between different liquid food rewards in the presence of pavlovian cues previously associated with one of these outcomes. We found behavioral evidence of outcome-specific transfer effects in our subjects, as well as differential blood oxygenation level-dependent activity in a region of ventrolateral putamen when subjects chose, respectively, actions consistent and inconsistent with the pavlovian-predicted outcome. Our results suggest that choosing an action incompatible with a pavlovian-predicted outcome might require the inhibition of feasible but nonselected action– outcome associations. The results of this study are relevant for understanding how marketing actions can affect consumer choice behavior as well as for how environmental cues can influence drug-seeking behavior in addiction
Construção de mapa genético e análise comparativa entre cruzamentos interespecíficos de Oryza glumaepatula x Oryza sativa utilizando marcadores microssatélites.
Este trabalho objetivou: 1) desenvolver um mapa genético baseado em marcadores SSR para o cruzamento interespecífico Oryza sativa (Cica 8) x Oryza glumaepatula (RS-16); 2) avaliar a conservação da ligação e ordem dos locos SSR entre dois mapas interespecíficos, os quais possuem o parental RS-16 em comum; 3) genotipar 118 famílias na geração RC2F1 obtida a partir do cruzamento interespecífico entre Oryza sativa (Cica 8) e Oryza glumaepatula (RS-16)
Photon and Pomeron -- induced production of Dijets in , and collisions
In this paper we present a detailed comparison of the dijet production by
photon -- photon, photon -- pomeron and pomeron -- pomeron interactions in
, and collisions at the LHC energy. The transverse
momentum, pseudo -- rapidity and angular dependencies of the cross sections are
calculated at LHC energy using the Forward Physics Monte Carlo (FPMC), which
allows to obtain realistic predictions for the dijet production with two
leading intact hadrons. We obtain that \gamma \pom channel is dominant at
forward rapidities in collisions and in the full kinematical range in the
nuclear collisions of heavy nuclei. Our results indicate that the analysis of
dijet production at the LHC can be useful to test the Resolved Pomeron model as
well as to constrain the magnitude of the absorption effects.Comment: 11 pages, 6 figures, 1 table. Improved and enlarged version published
in European Physical Journal
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