Reforming tax expenditure programs in Poland

Poland has recently begun reforming its tax program. In December 1999 it announced a gradual reduction in the corporate income tax rate, from 34 percent in 1999 to 22 percent in 2004. Value added and excise taxes are being harmonized with European Union directives, which means higher value added tax rates on unprocessed foodstuffs, municipal services, and construction material, and higher excise rates on tobacco and alcohol. The reform of personal income tax law has been delayed, because of concern about the fairness of a rate reduction for higher-income taxpayers and hesitation about the government's proposal to remove or scale down existing tax expenditure programs. Poland's personal income tax expenditure programs, introduced in 1992, have received growing attention as the cost of the programs has increased. Originally they were intended to compensate lower-income taxpayers for the withdrawal of price subsidies. But most of them are extremely regressive, benefiting higher-income taxpayers. Tax expenditures are reductions in tax liabilities that result from preferential provisions, such as deductions, exemptions, credits, deferrals, preferential tax rates, and exclusions from taxation. They are effective government spending channeled through the tax system, usually as substitutes for direct government spending to achieve fiscal and political objectives. The authors contend that strengthening the administration of Poland's tax expenditure programs is the first step toward making them effective and equitable, limiting their costs, and preventing the tax base from shrinking. They discuss options for increasing the scrutiny of the tax expenditure programs, defining their opportunity costs and effect on the tax system. Currently these programs enjoy a funding advantage over direct spending programs because they are not subject to systematic review. To limit the expansion of these programs and reduce their less desirable effects on the system, the authors suggest defining a benchmark tax structure, establishing sunset dates for the programs, forecasting their costs, and reviewing their economic effectiveness, efficiency, and equity by comparing them with direct expenditures and subsidies.Tax Policy and Administration,Public Sector Economics&Finance,Taxation&Subsidies,Environmental Economics&Policies,Strategic Debt Management

Aspectos do crescimento, desenvolvimento e manejo cultural do imbuzeiro.

O imbuzeiro (Spondias tuberosa Arr. Câm.) é uma fruteira nativa da região semi-árida do Nordeste brasileiro de grande importância socioeconômica para economia regional. Todavia, são poucos os estudos que visam o conhecimento mais detalhado da capacidade de sobrevivência e adaptação do imbuzeiro as condições adversas da região semi-árida, principalmente, aqueles que demonstrem seus mecanismos de adaptação, como o fechamento dos estômatos nas horas mais quentes do dia e a formação de xilopódios ou túberas em suas raíze

Índice de sobrevivência e crescimento do facheiro (Pilosocereus pachycladus Ritter.) na caatinga.

Este trabalho teve como objetivo verificar o índice de sobrevivência e o crescimento de cladódios do facheiro na caatinga. O trabalho foi realizado de agosto de 2000 a setembro de 2003 no Campo Experimental da Caatinga, localizada a 9º 24? 38? de latitude sul e 40º 29? 56? de longitude oeste na Embrapa Semi-Árido, em Petrolina-P

Resgate de germoplasma vegetal de espécies-alvo na área de influência do Aproveitamento Hidrelétrico Barra Grande (RS, SC).

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Restoring Heisenberg limit via collective non-Markovian dephasing

In this work an exactly solvable model of N two-level systems interacting with a single bosonic dephasing reservoir is considered to unravel the role played by collective non-Markovian dephasing. We show that phase estimation with entangled states for this model can exceed the standard quantum limit and demonstrate Heisenberg scaling with the number of atoms for an arbitrary temperature. For a certain class of reservoir densities of states decoherence can be suppressed in the limit of large number of atoms and the Heisenberg limit can be restored for arbitrary interrogation times. We identify the second class of densities when the Heisenberg scaling can be restored for any finite interrogation time. We also find the third class of densities when the standard quantum limit can be exceeded only on the initial stage of dynamics in the Zeno-regime.Comment: Accepted to Phys. Rev.