Tasa Efectiva del Impuesto a la Propiedad Inmueble en Puerto Rico: Análisis de caso de la implementación del impuesto predial en el municipio de Guaynabo

El análisis contenido en este artículo examina el comportamiento y los factores que afectan la tasa efectiva del impuesto sobre la propiedad inmueble en Puerto Rico, con la intención de establecer su impacto en la equidad del sistema impositivo. Los hallazgos del análisis son generalmente aplicables a aquellas jurisdicciones que no actualizan el proceso por el cual valorizan las propiedades inmuebles para fines contributivos, ni implementan mecanismos de corrección a sus ineficiencias. Entre los resultados más significativos se encuentra que la tasa efectiva del impuesto sobre la propiedad no es fija entre los inmuebles; específicamente, ésta penaliza a las propiedades con una mayor edad de haber sido construida y muestra un comportamiento regresivo

Opposing Effects of Sirtuins on Neuronal Survival: SIRT1-Mediated Neuroprotection Is Independent of Its Deacetylase Activity

Background: Growing evidence suggests that sirtuins, a family of seven distinct NAD-dependent enzymes, are involved in the regulation of neuronal survival. Indeed, SIRT1 has been reported to protect against neuronal death, while SIRT2 promotes neurodegeneration. The effect of SIRTs 3–7 on the regulation of neuronal survival, if any, has yet to be reported. Methodology and Principal Findings: We examined the effect of expressing each of the seven SIRT proteins in healthy cerebellar granule neurons (CGNs) or in neurons induced to die by low potassium (LK) treatment. We report that SIRT1 protects neurons from LK-induced apoptosis, while SIRT2, SIRT3 and SIRT6 induce apoptosis in otherwise healthy neurons. SIRT5 is generally localized to both the nucleus and cytoplasm of CGNs and exerts a protective effect. In a subset of neurons, however, SIRT5 localizes to the mitochondria and in this case it promotes neuronal death. Interestingly, the protective effect of SIRT1 in neurons is not reduced by treatments with nicotinamide or sirtinol, two pharmacological inhibitors of SIRT1. Neuroprotection was also observed with two separate mutant forms of SIRT1, H363Y and H355A, both of which lack deacetylase activity. Furthermore, LK-induced neuronal death was not prevented by resveratrol, a pharmacological activator of SIRT1, at concentrations at which it activates SIRT1. We extended our analysis to HT-22 neuroblastoma cells which can be induced to die by homocysteic acid treatment. While the effects of most of the SIRT proteins were similar to that observed in CGNs, SIRT6 was modestly protective against homocysteic acid toxicity in HT-22 cells. SIRT5 was generally localized in th

Effective valuation of the tax to the property building in Puerto Rico: analysis of case of the implementation of the predial tax in the municipality of Guaynabo

El análisis contenido en este artículo examina el comportamiento y los factores que afectan la tasa efectiva del impuesto sobre la propiedad inmueble en Puerto Rico, con la intención de establecer su impacto en la equidad del sistema impositivo. Los hallazgos del análisis son generalmente aplicables a aquellas jurisdicciones que no actualizan el proceso por el cual valorizan las propiedades inmuebles para fines contributivos, ni implementan mecanismos de corrección a sus ineficiencias. Entre los resultados más significativos se encuentra que la tasa efectiva del impuesto sobre la propiedad no es fija entre los inmuebles; específicamente, ésta penaliza a las propiedades con una mayor edad de haber sido construida y muestra un comportamiento regresivo.While trivial to the central government, property tax collections are the main source of revenues for municipalities in Puerto Rico, and almost every other country in the American continent. This paper empirically analyses the effective property tax rate in Puerto Rico intending to establish its impact on equity over the complete tax system. The general results applies to all jurisdictions not showing due diligence assessing the actual value of properties for taxation purposes, and proves that the implementation of the property tax in Puerto Rico is not directly imposed over the wealth derived from the real estate ownership and is in fact regressive

Finite Elements in the Presence of Occasionally Binding Constraints

Finite element method, Occasionally binding constraints, Irreversible investment, Optimal growth model,