Did Tax Policies mitigate US Business Cycles?

I study whether US Tax Policies affected economic volatility during the post World War II period. I employ a Real Business Cycle model with distorting taxation on household income and tax rules, and assume that taxes respond to the cyclical conditions of the economy. I estimate the deep parameters of the model using Bayesian techniques. My findings are; (a) fiscal policies display a strong countercyclical behavior, (b) help to reduce the cyclical and raw volatility of GDP, consumption, investment when the government can issue debt, and (c) unexpected changes in tax policies do not affect the volatility of the macroeconomic variables.Fiscal Policy and Business Cycles, Bayesian Methods.

Electrostatic Patch Effect in Cylindrical Geometry. III. Torques

We continue to study the effect of uneven voltage distribution on two close cylindrical conductors with parallel axes started in our papers [1] and [2], now to find the electrostatic torques. We calculate the electrostatic potential and energy to lowest order in the gap to cylinder radius ratio for an arbitrary relative rotation of the cylinders about their symmetry axis. By energy conservation, the axial torque, independent of the uniform voltage difference, is found as a derivative of the energy in the rotation angle. We also derive both the axial and slanting torques by the surface integration method: the torque vector is the integral over the cylinder surface of the cross product of the electrostatic force on a surface element and its position vector. The slanting torque consists of two parts: one coming from the interaction between the patch and the uniform voltages, and the other due to the patch interaction. General properties of the torques are described. A convenient model of a localized patch suggested in [2] is used to calculate the torques explicitly in terms of elementary functions. Based on this, we analyze in detail patch interaction for one pair of patches, namely, the torque dependence on the patch parameters (width and strength) and their mutual positions. The effect of the axial torque is then studied for the experimental conditions of the STEP mission.Comment: 28 pages, 6 Figures. Submitted to Classical Quantum Gravit

Crossover transition in bag-like models

We formulate a simple model for a gas of extended hadrons at zero chemical potential by taking inspiration from the compressible bag model. We show that a crossover transition qualitatively similar to lattice QCD can be reproduced by such a system by including some appropriate additional dynamics. Under certain conditions, at high temperature, the system consist of a finite number of infinitely extended bags, which occupy the entire space. In this situation the system behaves as an ideal gas of quarks and gluons.Comment: Corresponds to the published version. Added few references and changed the titl

Advanced Formation Fluid Evaluation While Drilling with a New Heavy Gas Detector

In this paper, a chromatograph which exploits the benefits of FID technology optimized for the high resolution detection of heavier hydrocarbon gas components is described. The components analyzed span from n-hexane to toluene. Flame Ionization Detector (FID) technology is not new to gas detection on the field, however it had never been applied to the detection of gases heavier than n-pentane. The instrumentation has been installed and run on a number of wells in different fields and countries, and it has operated as a complement of an advanced surface logging system for a period of two years. Unlike other technologies presently utilized for this scope, this system reduces dedicated equipment and personnel to a minimum. The results presented show the clear identification of formation fluid contacts with higher accuracy than standard light gas detectors, the recognition of contaminants within the drilling fluid, and the practicality of operating an advanced gas detection system with minimal operational and logistic footprint. Some of the indications obtained challenge common beliefs about gas detection: consistent extraction of heavy hydrocarbon gases from the drilling fluid is possible at relatively low temperatures, provided that the entire gas extraction system is rigorously controlled in terms of gas sample pressure, flow, and temperature. Furthermore, gas data analysis can yield indications on the fluid composition even when the gases analyzed are in extremely low quantity. The system utilizes known technologies, developed and optimized to obtain new results. The system supports formation evaluation when LWD or wireline can be inconclusive, in the presence of a low porosity pay or fresh water. It can also guide and optimize the MDT testing program. Furthermore, the system takes into account the constraints of drilling operations, and strikes a balance between data accuracy and practicality of the application

The regulation of exosome function in the CNS: implications for neurodegeneration

Exosomes are nanovesicles that have been shown to regulate neuronal development and regeneration, and modulate synaptic function

Graphene-based nanomaterials for tissue engineering in the dental field

The world of dentistry is approaching graphene-based nanomaterials as substitutes for tissue engineering. Apart from its exceptional mechanical strength, electrical conductivity and thermal stability, graphene and its derivatives can be functionalized with several bioactive molecules. They can also be incorporated into different scaffolds used in regenerative dentistry, generating nanocomposites with improved characteristics. This review presents the state of the art of graphene-based nanomaterial applications in the dental field. We first discuss the interactions between cells and graphene, summarizing the available in vitro and in vivo studies concerning graphene biocompatibility and cytotoxicity. We then highlight the role of graphene-based nanomaterials in stem cell control, in terms of adhesion, proliferation and differentiation. Particular attention will be given to stem cells of dental origin, such as those isolated from dental pulp, periodontal ligament or dental follicle. The review then discusses the interactions between graphene-based nanomaterials with cells of the immune system; we also focus on the antibacterial activity of graphene nanomaterials. In the last section, we offer our perspectives on the various opportunities facing the use of graphene and its derivatives in associations with titanium dental implants, membranes for bone regeneration, resins, cements and adhesives as well as for tooth-whitening procedure

Dynamic expression of homeostatic ion channels in differentiated cortical astrocytes in vitro

The capacity of astrocytes to adapt their biochemical and functional features upon physiological and pathological stimuli is a fundamental property at the basis of their ability to regulate the homeostasis of the central nervous system (CNS). It is well known that in primary cultured astrocytes, the expression of plasma membrane ion channels and transporters involved in homeostatic tasks does not closely reflect the pattern observed in vivo. The individuation of culture conditions that promote the expression of the ion channel array found in vivo is crucial when aiming at investigating the mechanisms underlying their dynamics upon various physiological and pathological stimuli. A chemically defined medium containing growth factors and hormones (G5) was previously shown to induce the growth, differentiation, and maturation of primary cultured astrocytes. Here we report that under these culture conditions, rat cortical astrocytes undergo robust morphological changes acquir- ing a multi-branched phenotype, which develops gradually during the 2-week period of culturing. The shape changes were paralleled by variations in passive membrane properties and background conductance owing to the differential temporal development of inwardly rectifying chloride (Cl−) and potassium (K+) currents. Confocal and immunoblot analyses showed that morphologically differentiated astrocytes displayed a large increase in the expression of the inward rectifier Cl− and K+ channels ClC-2 and Kir4.1, respectively, which are relevant ion channels in vivo. Finally, they exhibited a large diminution of the intermediate filaments glial fibrillary acidic protein (GFAP) and vimentin which are upregulated in reactive astrocytes in vivo. Taken together the data indicate that long-term culturing of cortical astrocytes in this chemical-defined medium promotes a quiescent functional phenotype. This culture model could aid to address the regulation of ion channel expression involved in CNS homeostasis in response to physiological and pathological challenge

Computational Fluid Dynamics of Reacting Flows at Surfaces: Methodologies and Applications

This review presents the numerical algorithms and speed-up strategies developed to couple continuum macroscopic simulations and detailed microkinetic models in the context of multiscale approaches to chemical reactions engineering. CFD simulations and hierarchical approaches are discussed both for fixed and fluidized systems. The foundations of the methodologies are reviewed together with specific examples to show the applicability of the methods. These concepts play a pivotal role to enable the first-principles multiscale approach to systems of technological relevance

La trasmissione delle lingue nello spazio domestico. Uno studio in famiglie italo-brasiliane residenti a San Paolo del Brasile

This paper aims to provide a snapshot of different ways of experiencing the linguistic repertoire (Brazilian Portuguese - Italian) within the intrafamily domain, by mixed families residing in São Paulo, Brazil. In light of the theoretical perspective defined as “linguistics of migration”, together with an investigation methodology that is based on the comparison between declarations and linguistic self-perceptions, obtained through autobiographies and productions, it was possible to assess different types of language transmission practices in a migratory context and to determine the degree of awareness that the first generation develops in order to maintain its linguistic repertoire

Non-steroidal anti-inflammatory drugs in cancer prevention and therapy

Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) can be regarded as an effective approach for cancer chemoprevention, as demonstrated by a bulk of clinical and experimental evidence. However, the clinical use of these drugs as chemopreventive agents is limited by many open questions about the optimal drug, dose, duration of therapy and knowledge about the mechanism(s) by which these drugs act. In particular, the recent data on cardiovascular toxicity of coxibs has posed some limitations on the use of NSAIDs for cancer chemoprevention in the general population. The situation is different in certain genetically susceptible subgroups, such as in individuals with genetic mutations associated with hereditary nonpolyposis colon cancer (HNPCC) or familiar adenomatous polyps (FAP) in whom lifetime risk increases up to 70-90% and in whom the benefit of a chemopreventive drug might justify its use even in the presence of adverse effects