Competitive elections, incumbency advantage, and accountability

I present a model of repeated electoral competition between two parties. A part of the electorate votes retrospectively and considers the amount of rent-seeking by the incumbent party, while the prospective voters follow probabilistic party preferences when casting their votes. I show that it is possible to distinguish the effects of incumbency advantage and electoral punishment on the minimum level of rent-seeking consistent with equilibrium. As long as there is electoral punishment for excessive rent-seeking, a larger incumbency advantage increases accountability by decreasing the minimum amount of rent-seeking consistent with equilibrium. The reason for this is that the larger the incumbency advantage is, the more important the result of the next election for all future election outcomes is. Consequently, the incumbent party is willing to give up more rent-seeking opportunities to improve its electoral prospects. Increased accountability due to a larger share of retrospective voters hurts the political selection aspect of elections because it enables the incumbent party to win without the support of the majority of the prospective voters

Lobbying and elections

I analyse the interaction between post-election lobbying and the voting decisions of forward-looking voters. The existing literature has shown that in models with citizen candidates from a dispersed distribution of preferences, lobbying has no influence on implemented policy. In my model with ideological parties, lobbying is shown to have an effect on policy. In terms of welfare, I show that the median voter and the majority of voters can be better off with lobbying

Lexicographic voting: holding parties accountable in the presence of Downsian competition

This paper combines ideas from models of electoral competition with forward-looking voters and models of electoral competition with backward-looking voters. Two political parties can commit in advance to policy platforms, but not to a maximum level of rent extraction. In the case without uncertainty, the electorate can limit rents to the same extent as in a purely backward-looking model of accountability, and the policy preferred by the voter who represents the median preferences of the electorate is implemented. In the case with uncertainty about the bliss point of the representative voter, the electorate has to accept higher rent seeking by the incumbent politician, but nonetheless retains some control over rent extraction. The policy positions of the two competing parties do not converge as they do in the case without uncertainty. I show in an example that this nonconvergence can increase the welfare of the representative voter

A semi‐active human digital twin model for detecting severity of carotid stenoses from head vibration—A coupled computational mechanics and computer vision method

In this work we propose a methodology to detect the severity of carotid stenosis from a video of a human face with the help of a coupled blood flow and head vibration model. This semi‐active digital twin model is an attempt to link non‐invasive video of a patient face to the percentage of carotid occlusion. The pulsatile nature of blood flow through the carotid arteries induces a subtle head vibration. This vibration is a potential indicator of carotid stenosis severity and it is exploited in the present study. A head vibration model has been proposed in the present work that is linked to the forces generated by blood flow with or without occlusion. The model is used to generate a large number of virtual head vibration data for different degrees of occlusion. In order to determine the in vivo head vibration, a computer vision algorithm is adopted to use human face videos. The in vivo vibrations are compared against the virtual vibration data generated from the coupled computational blood flow/vibration model. A comparison of the in vivo vibration is made against the virtual data to find the best fit between in vivo and virtual data. The preliminary results on healthy subjects and a patient clearly indicate that the model is accurate and it possesses the potential for detecting approximate severity of carotid artery stenoses

Dynamics of ferrocene in molecular sieves probed by Mossbauer spectroscopy and nuclear resonant scattering

A detailed study on the slow dynamics of ferrocene in the unidimensional channels of the molecular sieves SSZ-24 and AlPO4-5 has been carried out, using Mössbauer spectroscopy (MS), nuclear forward scattering (NFS) and synchrotron radiation-based perturbed angular correlations (SRPAC). In both host systems, anisotropic rotational dynamics is observed above 100 K. For SSZ-24, this anisotropy persists even above the bulk melting temperature of ferrocene. Various theoretical models are exploited for the study of anisotropic discrete jump rotations for the first time. The experimental data can be described fairly well by a jump model that involves reorientations of the molecular axis on a cone mantle with an opening angle dependant on temperature

Metastasis-inducing S100A4 protein is associated with the disease activity of rheumatoid arthritis

Objectives. To evaluate the association between metastasis-inducing protein S100A4 and disease activity in patients with RA, and to demonstrate the effect of TNF-alpha blocking therapy on plasma levels of S100A4 in these patients. Methods. Plasma levels of the S100A4 protein were analysed in 40 anti-TNF-alpha naive patients with active RA. Of the 40 patients, 25 were treated with adalimumab and monitored over time. The conformational form of S100A4 was analysed using size-exclusion gel chromatography. TNF-alpha mRNA expression and protein synthesis were analysed by RT-PCR and ELISA, respectively. Results. Baseline levels of S100A4 were significantly correlated with disease activity in RA patients (r = 0.41; P < 0.01). After 12 weeks of treatment with adalimumab, there was an obvious shift in the conformations of S100A4 from the multimeric to the dimeric forms, whereas the total levels of the S100A4 protein remained unchanged. This suggests that the bioactive (multimer) S100A4 may decline in response to successful treatment with adalimumab. In addition, we showed significant up-regulation of TNF-alpha mRNA (P < 0.01), and protein release to the cell culture medium of monocytes stimulated with the S100A4 multimer compared with those treated with the dimer and to the unstimulated monocytes (P < 0.001). Conclusions. This is the first study to show that the levels of the S100A4 protein are correlated with RA disease activity. Furthermore, only the bioactive form, but not the total amount of S100A4, decreases after successful TNF-alpha blocking therapy in patients with RA. These data support an important role for the S100A4 multimer in the pathogenesis of R

Raman-Mössbauer-XRD studies of selected samples from “Los Azulejos” outcrop: A possible analogue for assessing the alteration processes on Mars

The outcrop of “Los Azulejos” is visible at the interior of the Cañadas Caldera in Tenerife Island (Spain). It exhibits a great variety of alteration processes that could be considered as terrestrial analogue for several geological processes on Mars. This outcrop is particularly interesting due to the content of clays, zeolite, iron oxides, and sulfates corresponding to a hydrothermal alteration catalogued as “Azulejos” type alteration. A detailed analysis by portable and laboratory Raman systems as well as other different techniques such as X ray diffraction (XRD) and Mössbauer spectroscopy has been carried out (using twin-instruments from Martian lander missions: Mössbauer spectrometer MIMOS-II from the NASA-MER mission of 2001 and the XRD diffractometer from the NASA-MSL Curiosity mission of 2012). The mineral identification presents the following mineral species: magnetite, goethite, hematite, anatase, rutile, quartz, gregoryite, sulphate (thenardite and hexahydrite), diopside, feldspar, analcime, kaolinite and muscovite. Moreover, the in-situ Raman and Micro-Raman measurements have been performed in order to compare the capabilities of the portable system specially focused for the next ESA Exo-Mars mission. The mineral detection confirms the sub-aerial alteration on the surface and the hydrothermal processes by the volcanic fluid circulations in the fresh part. Therefore, the secondary more abundant mineralization acts as the color agent of the rocks. Thus, the zeolite-illite group is the responsible for the bluish coloration, as well as the feldspars and carbonates for the whitish and the iron oxide for the redish parts. The XRD system was capable to detect a minor proportion of pyroxene, which is not visible by Raman and Mössbauer spectroscopy due to the “Azulejos” alteration of the parent material on the outcrop. On the other hand, Mössbauer spectroscopy was capable of detecting different types of iron-oxides (Fe3+/2+-oxide phases). These analyses emphasize the strength of the different techniques and the working synergy of the three different techniques together for planetary space missions.The work was supported by the MICINN with the Project AYA-2008-04529.Peer reviewe

Athena MIMOS II Mossbauer spectrometer investigation

M&ouml;ssbauer spectroscopy is a powerful tool for quantitative mineralogical analysis of Fe-bearing materials. The miniature M&ouml;ssbauer spectrometer MIMOS II is a component of the Athena science payload launched to Mars in 2003 on both Mars Exploration Rover missions. The instrument has two major components: (1) a rover-based electronics board that contains power supplies, a dedicated central processing unit, memory, and associated support electronics and (2) a sensor head that is mounted at the end of the instrument deployment device (IDD) for placement of the instrument in physical contact with soil and rock. The velocity transducer operates at a nominal frequency of 25 Hz and is equipped with two 57Co/Rh M&ouml;ssbauer sources. The reference source (5 mCi landed intensity), reference target (alpha-Fe2O3 plus alpha-Fe0), and PIN-diode detector are configured in transmission geometry and are internal to the instrument and used for its calibration. The analysis M&ouml;ssbauer source (150 mCi landed intensity) irradiates Martian surface materials with a beam diameter of 1.4 cm. The backscatter radiation is measured by four PIN-diode detectors. Physical contact with surface materials is sensed with a switch-activated contact plate. The contact plate and reference target are instrumented with temperature sensors. Assuming 18% Fe for Martian surface materials, experiment time is 6&ndash;12 hours during the night for quality spectra (i.e., good counting statistics); 1&ndash;2 hours is sufficient to identify and quantify the most abundant Fe-bearing phases. Data stored internal to the instrument for selectable return to Earth include M&ouml;ssbauer and pulse-height analysis spectra (512 and 256 channels, respectively) for each of the five detectors in up to 13 temperature intervals (65 M&ouml;ssbauer spectra), engineering data for the velocity transducer, and temperature measurements. The total data volume is 150 kB. The mass and power consumption are 500 g (400 g for the sensor head) and 2 W, respectively. The scientific measurement objectives of the M&ouml;ssbauer investigation are to obtain for rock, soil, and dust (1) the mineralogical identification of iron-bearing phases (e.g., oxides, silicates, sulfides, sulfates, and carbonates), (2) the quantitative measurement of the distribution of iron among these iron-bearing phases (e.g., the relative proportions of iron in olivine, pyroxenes, ilmenite, and magnetite in a basalt), (3) the quantitative measurement of the distribution of iron among its oxidation states (e.g., Fe2+, Fe3+, and Fe6+), and (4) the characterization of the size distribution of magnetic particles. Special geologic targets of the M&ouml;ssbauer investigation are dust collected by the Athena magnets and interior rock and soil surfaces exposed by the Athena Rock Abrasion Tool and by trenching with rover wheels

In-situ Mössbauer Spectroscopy with MIMOS II at Rio Tinto, Spain

The Rio Tinto, located in southwest Spain, exhibits a nearly constant, acidic pHvalue along its course. Due to the formation of sulfate minerals, Rio Tinto is considered a potential analogue site for sulfate-rich regions on Mars, in particular at the landing site of the Mars Exploration Rover Opportunity, where the ferric sulfate mineral jarosite was identified with Opportunity's M&ouml;ssbauer spectrometer. Primary and secondary mineralogy was investigated in situ with portable Raman and M&ouml;ssbauer spectrometers at four different Rio Tinto sampling sites. The two techniques analyse different sample portions due to their specific field of view and sampling depth and provide complementary mineralogical information