Applications of electrified dust and dust devil electrodynamics to Martian atmospheric electricity

Atmospheric transport and suspension of dust frequently brings electrification, which may be substantial. Electric fields of 10 kVm-1 to 100 kVm-1 have been observed at the surface beneath suspended dust in the terrestrial atmosphere, and some electrification has been observed to persist in dust at levels to 5 km, as well as in volcanic plumes. The interaction between individual particles which causes the electrification is incompletely understood, and multiple processes are thought to be acting. A variation in particle charge with particle size, and the effect of gravitational separation explains to, some extent, the charge structures observed in terrestrial dust storms. More extensive flow-based modelling demonstrates that bulk electric fields in excess of 10 kV m-1 can be obtained rapidly (in less than 10 s) from rotating dust systems (dust devils) and that terrestrial breakdown fields can be obtained. Modelled profiles of electrical conductivity in the Martian atmosphere suggest the possibility of dust electrification, and dust devils have been suggested as a mechanism of charge separation able to maintain current flow between one region of the atmosphere and another, through a global circuit. Fundamental new understanding of Martian atmospheric electricity will result from the ExoMars mission, which carries the DREAMS (Dust characterization, Risk Assessment, and Environment Analyser on the Martian Surface)-MicroARES (Atmospheric Radiation and Electricity Sensor) instrumentation to Mars in 2016 for the first in situ measurements

Processos de democracia direta: sim ou não? Os argumentos clássicos à luz da teoria e da prática

Regularmente surgem controvérsias sobre os processos de democracia direta, dos quais os mecanismos mais frequentes são a iniciativa popular, o plebiscito e o referendo. Por um lado, há autores que defendem a posição de que essas instituições tornam o jogo político mais lento, caro, confuso e ilegítimo; outros defendem a posição contrária e argumentam que processos de democracia direta são fundamentais para os cidadãos e a qualidade da democracia. O presente estudo analisa esse tema em torno de sete questões, baseadas em considerações teóricas e pesquisas empíricas: 1. A questão entre o minimalismo e o maximalismo democrático; 2. A concorrência entre maioria e minoria; 3. A concorrência entre as instituições representativas e os processos de democracia direta; 4. A questão da competência dos cidadãos; 5. A questão dos efeitos colaterais dos processos de democracia direta; 6. A questão do tamanho do eleitorado; 7. A questão dos custos dos processos de democracia direta. As sete questões são analisadas a partir de uma revisão bibliográfica que considera tanto fontes nacionais como internacionais. O estudo mostra que os processos de democracia direta podem ser um complemento para as instituições representativas em um sistema democrático. O bom desempenho dos plebiscitos, referendos e iniciativas populares depende tanto da regulamentação destes como também do desempenho das outras instituições políticas e da situação socioeconômica de um país. O estudo permite ampliar e aprofundar o debate sobre processos de democracia direta no Brasil

Policy consequences of direct legislation theory, empirical models and evidence

Direct legislation, Referendums, Policy effects, Switching regression, US states,

Representative versus direct democracy: The role of informational asymmetries

The paper studies the relative merits of direct and representative legislation in a setting where voters are uncertain both with respect to the likely consequences of different policies and with respect to the political preferences of their fellow citizens. Under representative legislation, the latter translates into uncertainty on the elected official’s future policy intentions which involves a loss of control. The resulting discretionary power, however, also leads officials to endogenously acquire competence on the issues they oversee and specialize in policy formation. Policies determined in representative democracies are therefore better tailored to relevant contingencies but less close to the preferences of a majority than those determined in popular ballots. It is shown that the extent of the resulting trade-off depends on the set of alternatives among which the policy is to be chosen. Two extensions, referenda and the possibility of re-election, are briefly considered. Copyright Springer Science + Business Media, Inc. 2005

Public choice principles of redistricting

This paper uses fundamental principles of public choice, mainly the median voter theorem, to develop a simple theory of redistricting. The focus is on how closely policy outcomes correspond to majority rule. The main results are: (1) Potential policy bias in favor of nonmajority groups is structurally linked to the number of legislative seats and the population, and the structure of most states puts them very close to the theoretically maximum bias. (2) Random districting, which might seem like the essence of neutrality, does not eliminate policy bias on average. (3) Traditional principles of compact, contiguous districts that respect existing political boundaries, stressed in the Supreme Court’s Shaw v. Reno decision, minimize the chance of nonmajoritarian outcomes. Our analysis also offers a gerrymandering explanation for the positive relation between seats and spending that is usually taken as support for the “Law of 1/n.” Copyright Springer Science + Business Media B.V. 2006Redistricting, Voting rights, Median voter,

The European constitution project from the perspective of constitutional political economy

Three topics of a European constitution are discussed. First, basic arguments from constitutional political economy that aim at restricting representatives’ potential misuse of powers in a European Union with extended competencies are summarized. Since a European demos does not yet exist, an extension of competencies of the European Parliament is not sufficient in order to legitimate political decisions at the EU level. The introduction of elements of direct democracy in the European constitution would shape the creation of such a demos and lead to a stronger control of the European legislature and executive. Second, the introduction of direct democracy in the European constitution is proposed in order to reduce the European democratic deficit. Third, the creation of a European federation requires a more transparent assignment of competencies and rules to resolve conflicts between different centers of power. A European federation should be organized according to the principles of competitive federalism. Copyright Springer Science + Business Media, Inc. 2005