I Will Survive: Capital Taxation, Voter Turnout and Time Inconsistency

This paper reconsiders the debate around the political determination of capital income taxes and explains why such taxes survive in most OECD countries. The political economy literature on redistributive politics (Persson and Tabellini 2003) emphasizes the role played by the lower class in the political arena: being labor more concentrated than capital, the majority of the population benefits by overtaxing capital and undertaxing labour. However, in reality, political participation (voting, lobbying, protesting etc.) is positively correlated with income. Therefore, a paradoxical result emerges: why do the upper class, who is politically more active and own most of the capital, still favour a positive capital tax? Hence, voters' income is not the sole relevant variable in the political determination of the capital tax. To reconcile this apparent puzzle, we propose a model that incorporates time inconsistency à la Laibson in individual preferences We show that time inconsistent individuals are politically more homogeneous (or “single-minded”) than far-sighted, and prefer to tax more capital income, instead of labor income, since accumulated saving are below the planned (and optimal) level and the distortionary effects of a higher capital tax are not only reduced but also delayed in time. We demonstrate that, since politicians find easier to please hyperbolic voters by proposing a tax policy that includes lower labor and higher capital taxes compared to an economy with only far sighted. Moreover, we show that, as the proportion of time inconsistent individuals in the population increases, the tax policy becomes more and more biased towards capital taxation.Political Economy, Multidimensional Voting, Capital Taxation, Redistribution, Hyperbolic Discounting

An Egg Today and a Chicken Tomorrow: A Model of Social Security with Quasi-Hyperbolic Discounting

Strotz (1956) first suggested that individuals are more impatient when making short-run tradeoffs than long-run ones. Many experimental studies supports his conjecture. Motivated by recent evidence from the British Department of Work and Pension (2006), this paper applies this behavioral framework to retirement decisions. We propose a three-periods OLG model with quasi-hyperbolic consumers whosave for post retirement consumption in the first period and choose their retirement age in the second. We show that this behavioral assumption explains the observed drop in post retirement consumptiondue to lack of saving and the high level of voluntary (i.e. not due to disability or dismission from the firm) early exit from the labor force. When deciding about their retirement age, workers weight too much the costs of remaining at work (i.e. disutility of working, implicit tax on continued activity) and too little the benefits of postponed retirement (i.e. increase of the Bismarckian component of the pension formula), perceived as too far in the future. We investigate the implications of time inconsistent preferences for a political economy model in which voters determine simultaneously thesize and the degree of redistribution of the pension system. We show that, when voting over thepayroll tax, time inconsistent young workers, who look for a commitment device that increases boththeir saving and retirement age, form a coalition with rich in order to decrease the size of the system. When voting over the degree of redistribution, they form a coalition with poor individuals as to in-crease the at part of the pension formula. Our political model provides a political justification for the negative relationship between size and redistribution observed in most OECD countries (Disney 2004).Hyperbolic Discounting, Majority Voting, Redistribution, Retirement Age, Saving Behaviour

Decoherence due to gravitational time dilation: analysis of competing decoherence effects

Recently, a static gravitational field, such as that of the Earth, was proposed as a new source of decoherence [1]. We study the conditions under which it becomes the dominant decoherence effect in typical interferometric experiments. The following competing sources are considered: spontaneous emission of light, absorption, scattering with the thermal photons and collisions with the residual gas. We quantify all these effects. As we will see, current experiments are off by several orders of magnitude. New ideas are needed in order to achieve the necessary requirements: having as large as system as possible, to increase gravitational decoherence, cool it and isolated well enough to reduce thermal and collisional decoherence, and resolve very small distances.Comment: 6 pages, 3 figure

Adjoint master equation for Quantum Brownian Motion

Quantum brownian motion is a fundamental model for a proper understanding of open quantum systems in different contexts such as chemistry, condensed matter physics, bio-physics and opto- mechamics. In this paper we propose a novel approach to describe this model. We provide an exact and analytic equation for the time evolution of the operators, and we show that the corresponding equation for the states is equivalent to well-known results in literature. The dynamics is expressed in terms of the spectral density, regardless the strength of the coupling between the system and the bath. Our allows to compute the time evolution of physically relevant quantities in a much easier way than previous formulations allow to. An example is explicitly studied.Comment: Minor change

Increased biomass productivity in green algae by tuning non-photochemical quenching

Photosynthetic microalgae have a high potential for the production of biofuels and highly valued metabolites. However, their current industrial exploitation is limited by a productivity in photobioreactors that is low compared to potential productivity. The high cell density and pigment content of the surface layers of photosynthetic microalgae result in absorption of excess photons and energy dissipation through non-photochemical quenching (NPQ). NPQ prevents photoinhibition, but its activation reduces the efficiency of photosynthetic energy conversion. In Chlamydomonas reinhardtii, NPQ is catalyzed by protein subunits encoded by three lhcsr (light harvesting complex stress related) genes. Here, we show that heat dissipation and biomass productivity depends on LHCSR protein accumulation. Indeed, algal strains lacking two lhcsr genes can grow in a wide range of light growth conditions without suffering from photoinhibition and are more productive than wild-type. Thus, the down-regulation of NPQ appears to be a suitable strategy for improving light use efficiency for biomass and biofuel production in microalgae

Multilayer test masses to enhance the collapse noise

Recently, nonthermal excess noise, compatible with the theoretical prediction provided by collapse models, was measured in a millikelvin nanomechanical cantilever experiment [A. Vinante et al., Phys. Rev. Lett. 119, 110401 (2017)]. We propose a feasible implementation of the cantilever experiment able to probe such noise. The proposed modification, completely within the grasp of current technology and readily implementable also in other types of mechanical noninterferometric experiments, consists in replacing the homogeneous test mass with one composed of different layers of different materials. This will enhance the action of a possible collapse noise above that given by standard noise sources

Innovative Local Development Initiatives in the Eastern Alps: Forest Therapy, Land Consolidation Associations and Mountaineering Villages

Since the 19th century, Italy’s mountain regions have suffered from depopulation and land abandonment. How can we counter this phenomenon? Here, we present three cases of innovative and participatory approaches implemented in the Eastern Alps of Friuli Venezia Giulia. Forest therapy is a new approach to medical therapy based on the beneficial effects on the human health of frequenting forests. It also has the potential to provide space for local economic initiatives, e.g., hospitality services. Land consolidation associations were created in France to collectively restore the productivity of fragmented and abandoned farmland. They can evolve into long-term planning for the conservation of landed wealth and the valorization of territories. Finally, Mountaineering villages have the potential to develop a more sustainable form of tourism by fostering a sense of responsibility for the natural and cultural heritage of the European Alps, in accordance with the Alpine onvention. These initiatives share the involvement of local actors in the definition of local development strategies, the capability of enhancing endogenous resources and increasing the environmental value of places, the importance of offering qualified and organized services, and the ability to support the local socioeconomic system. The adoption of innovative and participatory approaches such as these has the potential to revert depopulation and economic depression trends in mountain areas

Analysis and Design of Radio Frequency Integrated Circuits for Breast Cancer Radar Imaging in CMOS Technology

Breast cancer is by far the most incident tumor among female population. Early stage prevention is a key factor in delivering long term survival of breast cancer patients. X-ray mammography is the most commonly used diagnostic technique to detect non-palpable tumors. However, 10-30% of tumors are missed by mammography and ionizing radiations together with breast compression do not lead to comfort in patient treatment. In this context, ultrawideband microwave radar technology is an attractive alternative. It relies on the dielectric contrast of normal and malignant tissues at microwave frequencies to detect and locate tumors inside the breast. This work presents the analysis and design of radio frequency integrated circuits for breast cancer imaging in CMOS technology. The first part of the thesis concerns the system analysis. A behavioral model of two different transceiver architectures for UWB breast cancer imaging employing a SFCW radar system are presented. A mathematical model of the direct conversion and super heterodyne architectures together with a numerical breast phantom are developed. FDTD simulations data are used to on the behavioral model to investigate the limits of both architectures from a circuit-level point of view. Insight is given into I/Q phase inaccuracies and their impact on the quality of the final reconstructed images. The result is that the simplicity of the direct conversion architecture makes the receiver more robust toward the critical impairments for this application. The second part of the thesis is dedicated to the circuit design. The main achievement is a 65nm CMOS 2-16GHz stepped frequency radar transceiver for medical imaging. The RX features 36dB conversion gain, >29dBm compression point, 7dB noise figure, and 30Hz 1/f noise corner. The TX outputs 14dBm with >40dBc harmonic rejection and <109dBc/Hz phase noise at 1MHz offset. Overall power dissipation is 204mW from 1.2V supply. The radar achieves 3mm resolution within the body, and 107dB dynamic range, a performance enabling the use for breast cancer diagnostic imaging. To further assess the capabilities of the proposed radar, a physical breast phantom was synthesized and two targets mimicking two tumors were buried inside the breast. The targets are clearly identified and correctly located, effectively proving the performance of the designed radar as a possible tool for breast cancer detection

Contrasting behavior of higher plant photosystem I and II antenna systems during acclimation

In this work we analyzed the photosynthetic apparatus in Arabidopsis thaliana plants acclimated to different light intensity and temperature conditions. Plants showed the ability to acclimate into different environments and avoid photoinhibition. When grown in high light, plants had a faster activation rate for energy dissipation (qE). This ability was correlated to higher accumulation levels of a specific photosystem II subunit, PsbS. The photosystem II antenna size was also regulated according to light exposure; smaller antenna size was observed in high light-acclimated plants with respect to low light plants. Different antenna polypeptides did not behave similarly, and Lhcb1, Lchb2, and Lhcb6 (CP24) are shown to undergo major levels of regulation, whereas Lhcb4 and Lhcb5 (CP29 and CP26) maintained their stoichiometry with respect to the reaction center in all growth conditions. The effect of acclimation on photosystem I antenna was different; in fact, the stoichiometry of any Lhca antenna proteins with respect to photosystem I core complex was not affected by growth conditions. Despite this stability in antenna stoichiometry, photosystem I light harvesting function was shown to be regulated through different mechanisms like the control of photosystem I to photosystem II ratio and the association or dissociation of Lhcb polypeptides to photosystem I