Optimal Budget Deficit Rules

This paper discusses the problem of the optimal determination of budget deficit limits in cases where the fiscal authority wishes to keep the budget deficit close to a reference value. It is assumed that the fiscal authority minimizes the expected discounted value of squared deviations from the reference value. Lump-sum and proportional intervention costs are considered. This paper is also an example of integration between stochastic process optimal control methods and the continuous time stochastic models. In fact, the characteristics of the stochastic process that rules the path of the budget deficit are taken from a previously developed continuous time stochastic model (Amador, 1999). Finally, simulation methods are used in order to conduct a comparative dynamics analysis. The paper concludes that, in the case of proportional intervention costs, the optimal ceiling depends positively on the cost parameter and on the variance of the budget deficit. On the contrary, the optimal ceiling depends negatively on the average budget deficit. These results remain valid in the case where there are both lump-sum and proportional intervention costs. Finally, in a stationary equilibrium context, we conclude that economies with higher tax rates and lower public expenditure should set higher budget deficit ceilings. The same is true for economies with a higher variance in technology and public expenditure shocks.

Automated Identification and Differentiation of Spectrally Similar Hydrothermal Minerals on Mars

Early telescopic observations corroborated hydration related absorptions on Mars in the infrared. Images from the Viking missions led to speculation of hydrothermal alteration and were followed by two missions which mapped the spatial variability of the ~ 3 m hydration feature. Since then, the Compact Reconnaissance Imager for Mars (CRISM) has provided high spatial resolution (up to 18m) spectral identification of a suite of hydrothermal and diagenetic minerals which have illuminated a range of formation mechanisms. Presence/absence and spatial segregation or mixing of minerals like prehnite, epidote, chlorite amphiboles, and mixed-layer Fe/Mg smectite-chlorite provide valuable evidence for the geologic setting of deposits on Earth, and these phases are often used as temperature and aqueous chemistry indicators in terrestrial systems. Mapping the distribution of these phases will help to answer whether Mars had widespread conditions favorable for low-grade metamorphism and diagenesis, or only focused hydrothermal systems in areas of high heat flow. Further characterizing the chemistry and structure of these phases will then help to answer how most of the widespread Fe/Mg phyllosilicates formed, further defining early geochemical cycling and climate. A fully automated approach for accurate mapping of important hydrothermal mineral phases on Mars has been a challenge. Due to overlapping features in the M-OH region (~2.2-2.4 m), the strongest absorption features of chlorite, prehnite, and epidote in the short-wave infrared are difficult to distinguish from one another and from the most commonly occurring hydrated silicates on Mars, Fe/Mg smectites. Weaker absorptions are present in both prehnite and epidote which help to distinguish them from chlorite and smectites, but their relative strength in the presence of noise and spatial mixing is often too low to confidently identify them without the noise suppression and feature enhancement methods described here. The spectral signatures of mixed-layer Fe/Mg smectite-chlorite and partially chloritized Fe/Mg smectites have not yet been adequately assessed. Here we evaluate the effectiveness of two empirical and statistical methods for identifying and differentiating these phases using CRISM data

The Agendas 21 of the Cordoba province. The identification of sustainability indicators, their diffusion and their impact on decision making

En la provincia de Córdoba se está consolidando la implantación de Agendas 21 tanto en lo que respecta a las Agendas 21 Locales como a la Agenda 21 Provincial. Una vez superadas las etapas iniciales, en la cuales se sientan las bases del proceso y se desarrolla la planificación estrategia hacia la sostenibilidad, resulta necesario plantear la puesta en valor de los logros alcanzados, sobre todo considerando la explotación de los indicadores de sostenibilidad ya determinadosIn the Cordoba province is consolidating the implenentation of Agenda 21 as in regard to Local Agenda 21 as to the Provincial. Once you get past the initial stages, in which the foundations of the process and develop the planning strategy towards sustainability, it is necessary to consider the enhancement of the achievements, above all considering the use of sustainability indicators already certainPeer Reviewe

A systematic review and critical appraisal of quality indicators to assess optimal palliative care for older people with dementia

© The Author(s) 2019Background: A challenge for commissioners and providers of end-of-life care in dementia is to translate recommendations for good or effective care into quality indicators that inform service development and evaluation. Aim: To identify and critically evaluate quality indicators for end-of-life care in dementia. Results: We found 8657 references, after de-duplication. In all, 19 publications describing 10 new and 3 updated sets of indicators were included in this review. Ultimately, 246 individual indicators were identified as being relevant to dementia end-of-life care and mapped against EAPC guidelines. Conclusions: We systematically derived and assessed a set of quality indicators using a robust framework that provides clear definitions of aspects of palliative care, which are dementia specific, and strengthens the theoretical underpinning of new complex interventions in end-of-life care in dementia.Peer reviewedFinal Published versio

Morphological and functional effects of graphene on the synthesis of uranium carbide for isotopes production targets

AbstractThe development of tailored targets for the production of radioactive isotopes represents an active field in nuclear research. Radioactive beams find applications in nuclear medicine, in astrophysics, matter physics and materials science. In this work, we study the use of graphene both as carbon source for UO2 carbothermal reduction to produce UCx targets, and also as functional properties booster. At fixed composition, the UCx target grain size, porosity and thermal conductivity represent the three main points that affect the target production efficiency. UCx was synthesized using both graphite and graphene as the source of carbon and the target properties in terms of composition, grain size, porosity, thermal diffusivity and thermal conductivity were studied. The main output of this work is related to the remarkable enhancement achieved in thermal conductivity, which can profitably improve thermal dissipation during operational stages of UCx targets.</jats:p

Spin-dependent electronic conduction along zigzag graphene nanoribbons bearing adsorbed Ni and Fe nanostructures

Using SMEAGOL, an ab initio computational method that combines the non-equilibrium Green's function formalism with density-functional theory, we calculated spin-specific electronic conduction in systems consisting of single Fen and Nin nanostructures (n = 1−4) adsorbed on a hydrogen-passivated zigzag graphene nanoribbon. For each cluster we considered both ferromagnetically and antiferromagnetically coupled ribbon edges (Ferro-F and Ferro-A systems, respectively). Adstructures located laterally on Ferro-A ribbons caused significant transmittance loss at energies 0.6–0.25 eV below the Fermi level for one spin and 0.2–0.4 eV above the Fermi level for the other, allowing the potential use of these systems in transistors to create a moderately spin-polarized current of one or the other sign depending on the gate voltage. Ni₃ and Ni₄ clusters located at the centre of Ferro-F ribbons exhibited a strong spin-filtering effect in a narrow energy window around the Fermi level

Spin currents and filtering behavior in zigzag graphene nanoribbons with adsorbed molybdenum chains

By means of density-functional-theoretic calculations, we investigated the structural, electronic and transport properties of hydrogen-passivated zigzag graphene nanoribbons (ZGNRs) on which a one-atom-thick Mo chain was adsorbed (with or without one or two missing atoms), or in which the passivating hydrogen atoms were replaced by Mo atoms. Mo-passivated ZGNRs proved to be nonmagnetic. ZGNRs with an adsorbed defect-free Mo chain were most stable with the Mo atoms forming dimers above edge bay sites, which suppressed the magnetic moments of the C atoms in that half of the ribbon; around the Fermi level of these systems, each spin component had a transmission channel via the Mo spz band and one had an additional channel created by polarization of the ZGNR π* band, leading to a net spin current. The absence of an Mo dimer from an Mo chain adsorbed at the ZGNR edge made the system a perfect spin filter at low voltage bias by suppressing the Mo spz band channels. Thus this last kind of hybrid system is a potential spin valve

Decomposing the impacts of overeducation and overskilling on earnings and job satisfaction: an analysis using REFLEX data.

This article assesses the extent to which the impact of overeducation and overskilling on labour market outcomes such as earnings and job satisfaction relate to mismatches in particular competency areas. The analysis uses REFLEX data, which collects information about 19 key competence areas related to job performance. We find that the penalties to both forms of mismatch are insensitive to the inclusion of controls for overskilling in a wide range of jobspecific competencies. The research suggests that the problem of mismatch relates to an inability to fully utilise general or innate ability as opposed to specific areas of acquired learning. We conclude that the problem of mismatch can only be effectively addressed by raising general levels of job quality within developed labour markets