1,331 research outputs found
Nonlinear Micromechanical Casimir Oscillator
The Casimir force between uncharged metallic surfaces originates from quantum
mechanical zero point fluctuations of the electromagnetic field. We demonstrate
that this quantum electrodynamical effect has a profound influence on the
oscillatory behavior of microstructures when surfaces are in close proximity
(<= 100 nm). Frequency shifts, hysteretic behavior and bistability caused by
the Casimir force are observed in the frequency response of a periodically
driven micromachined torsional oscillator.Comment: 4 pages, 4 figures; added and rearranged references; added comments
on sensitivit
Targeted Enforcement against Illicit Trade in Tobacco Products
Illicit trade in tobacco is a substantial and growing problem in the U.S., causing loss of tax revenue, damage to public health, and threats to public safety. Decisions about enforcement against ITTP involve tradeoffs among competing objectives. Good policy design can improve the terms of those tradeoffs but cannot eliminate them. We examine questions about the allocation of enforcement resources against ITTP, and its distribution across activities, individuals, and organizations: in particular, whether and how to differentially target ITTP that involves violence or support for terrorism. We consider the problem of developing effective strategies for enforcement, applying both lessons from experience with markets for illicit drugs and theoretical insights about enforcement targeting and dynamic concentration. We show that targeted enforcement and focused deterrence are more efficient than unfocused enforcement, and that â when other policy changes increase the potential rewards to illicit activity â enforcement resources applied earlier (before illicit markets have grown) will have greater impact than enforcement resources applied later (and therefore to larger markets). We discuss additional considerations, ranging from real-world complications left out of the simple models to examination of how insights from behavioral law and economics may modify conclusions based on a theory of deterrence designed for homo economicus
Countervailing Effects: What the FDA Would Have to Know to Evaluate Tobacco Regulations
The Family Smoking Prevention and Tobacco Control Act [P.L. 111-31] gives the US Food and Drug Administration (FDA) the authority to regulate tobacco products, including placing restrictions on product composition, sale, and distribution. A complete accounting of the costs and benefits of any tobacco regulation includes harms from possible illicit trade in tobacco products (ITTP): costs of enforcement, violence, incarceration, etc. Indeed, the law instructs the FDA to take into account the âcountervailing effectsâ of regulation on public health, âsuch as the creation of a significant demand for contraband or other tobacco products that do not meet the requirements.â While the lawâs narrow focus on public health may limit the scope of an inquiry by the FDA compared to a full benefit-cost analysis, aspects of ITTP such as violence and incarceration have substantial health impacts. Illicit markets in drugs such as cocaine, heroin, and methamphetamine, not to mention the grand experiment of alcohol Prohibition in the early 20th century, illustrate the substantial risks of unwanted side effects of drug prohibition. But taxes, product limitations, access restrictions, and narrowly defined product bans constitute âlesser prohibitions,â and are subject to the same kind (if not degree) of risks. All tobacco policy-making should therefore consider ITTP. This article sets forth a research agenda for the FDA to consider in order to estimate the effects of contemplated tobacco-product regulation and ITTP. We argue that, to carry out fully its legislative mandate, the FDA would have to determine the current size and impact of ITTP, analyze how these may be expected to change under new regulations, and look for interdependencies among tobacco-product markets that may complicate single-product regulation. A more challenging element of the research agenda would be to develop a better theoretical groundwork for the prediction of the emergence, size, and side effects of illicit markets
Unintended Consequences of Cigarette Prohibition, Regulation, and Taxation
Abstract Laws that prohibit, regulate, or tax cigarettes can generate illicit markets for tobacco products. Illicit markets both reduce the efficacy of policies intended to improve public health and create harms of their own. Enforcement can reduce evasion but creates additional harms, including incarceration and violence. There is strong evidence that more enforcement in illicit drug markets can spur violence. The presence of licit substitutes, such as electronic cigarettes, has the potential to greatly reduce the size of illicit markets. We present a model demonstrating why enforcement can increase violence, show that states with higher tobacco taxes have larger illicit markets, and apply the findings to discussion of public policy toward a potential ban on menthol cigarettes. The social calculus involved in determining public policy toward tobacco cigarettes should include the harms from both consumption and control. We conclude by highlighting areas where more research is needed for effective policymaking
Material Support: Counternarcotics vs. Counterinsurgency in Afghanistan
Microeconomic analysis of counternarcotics strategies in Afghanistan suggests that current policies lend material support to the enemy. Vigorous enforcement can increase the flow of funds to insurgents and other parties that profit from trafficking. Rural-development programs, promoted as elements of a counternarcotics strategy, are open to some of the same objections. The benefits of drug-fighting in Afghanistan for consumer countries in Europe and North America are likely to be modest. Anti-corruption efforts in Afghanistan and demand-reduction programs both in Afghanistan and in consumer countries, insofar as they are feasible, could serve both counternarcotics and counterinsurgency objectives
Adenosine echocardiography with or without handgrip in the diagnosis of coronary artery disease: Comparison with exercise echocardiography
Moduli of mathematical instanton vector bundles with odd c_2 on projective space
The problem of irreducibility of the moduli space I_n of rank-2 mathematical
instanton vector bundles with arbitrary positive second Chern class n on the
projective 3-space is considered. The irreducibility of I_n was known for small
values of n: Barth 1977 (n=1), Hartshorne 1978 (n=2), Ellingsrud and Stromme
1981 (n=3), Barth 1981 (n=4), Coanda, Tikhomirov and Trautmann 2003 (n=5). In
this paper we prove the irreducibility of I_n for an arbitrary odd n.Comment: 62 page
Perturbation of Tunneling Processes by Mechanical Degrees of Freedom in Mesoscopic Junctions
We investigate the perturbation in the tunneling current caused by
non-adiabatic mechanical motion in a mesoscopic tunnel junction. A theory
introduced by Caroli et al. \cite{bi1,bi2,bi3} is used to evaluate second order
self-energy corrections for this non-equilibrium situation lacking
translational invariance. Inelastic signatures of the mechanical degrees of
freedom are found in the current-voltage characteristics. These give
rise to sharp features in the derivative spectrum, .Comment: 22 pages LaTeX + 3 uuencoded PS picture
Democratic cultural policy : democratic forms and policy consequences
The forms that are adopted to give practical meaning to democracy are assessed to identify what their implications are for the production of public policies in general and cultural policies in particular. A comparison of direct, representative, democratic elitist and deliberative versions of democracy identifies clear differences between them in terms of policy form and democratic practice. Further elaboration of these differences and their consequences are identified as areas for further research
Integral Grothendieck-Riemann-Roch theorem
We show that, in characteristic zero, the obvious integral version of the
Grothendieck-Riemann-Roch formula obtained by clearing the denominators of the
Todd and Chern characters is true (without having to divide the Chow groups by
their torsion subgroups). The proof introduces an alternative to Grothendieck's
strategy: we use resolution of singularities and the weak factorization theorem
for birational maps.Comment: 24 page
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