FRW barotropic zero modes: Dynamical systems observability

The dynamical systems observability properties of barotropic bosonic and fermionic FRW cosmological oscillators are investigated. Nonlinear techniques for dynamical analysis have been recently developed in many engineering areas but their application has not been extended beyond their standard field. This paper is a small contribution to an extension of this type of dynamical systems analysis to FRW barotropic cosmologies. We find that determining the Hubble parameter of barotropic FRW universes does not allow the observability, i.e., the determination of neither the barotropic FRW zero mode nor of its derivative as dynamical cosmological states. Only knowing the latter ones correspond to a rigorous dynamical observability in barotropic cosmologyComment: 10 pages, 0 figure

PAMELA's cosmic positron from decaying LSP in SO(10) SUSY GUT

We propose two viable scenarios explaining the recent observations on cosmic positron excess. In both scenarios, the present relic density in the Universe is assumed to be still supported by thermally produced WIMP or LSP (\chi). One of the scenarios is based on two dark matter (DM) components (\chi,X) scenario, and the other is on SO(10) SUSY GUT. In the two DM components scenario, extremely small amount of non-thermally produced meta-stable DM component [O(10^{-10}) < n_X /n_\chi] explains the cosmic positron excess. In the SO(10) model, extremely small R-parity violation for LSP decay to e^\pm is naturally achieved with a non-zero VEV of the superpartner of one right-handed neutrino (\tilde{\nu}^c) and a global symmetry.Comment: 6 pages, Talks presented in PASCOS, SUSY, and COSMO/CosPA in 201

Protein adsorption onto Fe3O4 nanoparticles with opposite surface charge and its impact on cell uptake

Nanoparticles (NPs) engineered for biomedical applications are meant to be in contact with protein-rich physiological fluids. These proteins are usually adsorbed onto the NP surface, forming a swaddling layer called protein corona that influences cell internalization. We present a study on protein adsorption onto different magnetic NPs (MNPs) when immersed in cell culture medium, and how these changes affect the cellular uptake. Two colloids with magnetite cores of 25 nm, same hydrodynamic size and opposite surface charge were in situ coated with (a) positive polyethyleneimine (PEI-MNPs) and (b) negative poly(acrylic acid) (PAA-MNPs). After few minutes of incubation in cell culture medium the wrapping of the MNPs by protein adsorption resulted in a 5-fold size increase. After 24 h of incubation large MNP-protein aggregates with hydrodynamic sizes 1500 to 3000 nm (PAA-MNPs and PEI-MNPs respectively) were observed. Each cluster contained an estimated number of magnetic cores between 450 and 1000, indicating the formation of large aggregates with a "plum pudding" structure of MNPs embedded into a protein network of negative surface charge irrespective of the MNP_core charge. We demonstrated that PEI-MNPs are incorporated in much larger amounts than the PAA-MNPs units. Quantitative analysis showed that SH-SY5Y cells can incorporate 100 per cent of the added PEI-MNPs up to about 100 pg per cell, whereas for PAA-MNPs the uptake was less than 50 percent. The final cellular distribution showed also notable differences regarding partial attachment to the cell membrane. These results highlight the need to characterize the final properties of MNPs after protein adsorption in biological media, and demonstrate the impact of these properties on the internalization mechanisms in neural cells.Comment: 32 pages, 10 figure

Mexican northern border municipalities, financial dependence and institutions

Mexican northern border municipalities have experienced economic and populational growth rates that are much higher than other Mexican regions resulting in higher demand for public services and infrastructure. The different institutional framework, both fiscal and legal, faced by municipalities in every Mexican State might impact the fiscal behavior of local governments. This article examines whether border municipalities are more financially dependent on central authorities due to the high demand for public services in their jurisdictions and their inability to obtain sufficient funding. Several econometric models are estimated for 300 Mexican municipalities in the year 2000. A strong and negative relationship between income and financial dependence is found, as expected. We also learned that institutional and regional factors should not be omitted in the model specifications. Statistical theory based on the estimations shows that the border municipalities of Ciudad Juárez and Puerto Peñasco have systematically lower financial dependence than others. However, there is no general rule regarding border municipalities and financial dependence

Application of multifractal wavelet analysis to spontaneous fermentation processes

An algorithm is presented here to get more detailed information, of mixed culture type, based exclusively on the biomass concentration data for fermentation processes. The analysis is performed with only the on-line measurements of the redox potential being available. It is a two-step procedure which includes an Artificial Neural Network (ANN) that relates the redox potential to the biomass concentrations in the first step. Next, a multifractal wavelet analysis is performed using the biomass estimates of the process. In this context, our results show that the redox potential is a valuable indicator of microorganism metabolic activity during the spontaneous fermentation. In this paper, the detailed design of the multifractal wavelet analysis is presented, as well as its direct experimental application at the laboratory levelComment: 12 pages, 3 figures, Physica A, to appea

Autonomous systems thermographic NDT of composite structures

Transient thermography is a method used successfully in the evaluation of composite materials and aerospace structures. It has the capacity to deliver both qualitative and quantitative results about hidden defects or features in a composite structure. Aircraft must undergo routine maintenance – inspection to check for any critical damage and thus to ensure its safety. This work aims to address the challenge of NDT automated inspection and improve the defects’ detection by suggesting an autonomous thermographic imaging approach using a UAV (Unmanned Aerial Vehicle) active thermographic system. The concept of active thermography is discussed and presented in the inspection of aircraft CFRP panels along with the mission planning for aerial inspection using the UAV for real time inspection. Results indicate that the suggested approach could significantly reduce the inspection time, cost, and workload, whilst potentially increase the probability of detection of defects on aircraft composites