CloudChain: A novel distribution model for digital products based on supply chain principles

Cloud computing is a popular outsourcing solution for organizations to support the information management during the life cycle of digital information goods. However, outsourcing management with a public provider results in a lack of control over digital products, which could produce incidents such as data unavailability during service outages, violations of confidentiality and/or legal issues. This paper presents a novel distribution model of digital products inspired by lean supply chain principles called CloudChain, which has been designed to support the information management during digital product lifecycle. This model enables connected networks of customers, partners and organizations to conduct the stages of digital product lifecycle as value chains. Virtual distribution channels are created over cloud resources for applications of organizations to deliver digital products to applications of partners through a seamless information flow. A configurable packing and logistic service was developed to ensure confidentiality and privacy in the product delivery by using encrypted packs. A chain management architecture enables organizations to keep tighter control over their value chains, distribution channels and digital products. CloudChain software instances were integrated to an information management system of a space agency. In an experimental evaluation CloudChain prototype was evaluated in a private cloud where the feasibility of applying supply chain principles to the delivery of digital products in terms of efficiency, flexibility and security was revealed.This work was partially funded by the sectorial fund of research, technological development and innovation in space activities of the Mexican National Council of Science and Technology (CONACYT) and the Mexican Space Agency (AEM), project No. 262891

Generación de estados superficiales durante la formación electroforética catódica de películas de TiO2 sobre ito

In the present work TiO2 films were formed over Indium Tin Oxide (ITO) employing cathodic electrophoretic deposition (Cathodic-EPD) and Dr. Blade Technique. The films were characterized by electrochemical techniques in order to compare their electronic properties; as well as, their photoelectrochemical behavior. The electrochemical performance showed by the films, allowed to relate the modification occurring during the Cathodic-EPD, with the partial reduction of TiO2 nanoparticles, generating Ti3+ defects. These trapping states are modifying the electronic properties of the film, and diminishing the transport of the photoelectrogenerated electrons toward ITO

Stark effect in a wedge-shaped quantum box

The effect of an external applied electric field on the electronic ground state energy of a quantum box with a geometry defined by a wedge is studied by carrying out a variational calculation. This geometry could be used as an approximation for a tip of a cantilever of an atomic force microscope. We study theoretically the Stark effect as function of the parameters of the wedge: its diameter, angular aperture and thickness; as well as function of the intensity of the external electric field applied along the axis of the wedge in both directions; pushing the carrier towards the wider or the narrower parts. A confining electronic effect, which is sharper as the wedge dimensions are smaller, is clearly observed for the first case. Besides, the sign of the Stark shift changes when the angular aperture is changed from small angles to angles theta>pi. For the opposite field, the electronic confinement for large diameters is very small and it is also observed that the Stark shift is almost independent with respect to the angular aperture.Comment: 23 pages, 9 figures, 1 tabl

Continuous opinion model in small world directed networks

In the compromise model of continuous opinions proposed by Deffuant et al, the states of two agents in a network can start to converge if they are neighbors and if their opinions are sufficiently close to each other, below a given threshold of tolerance $\epsilon$. In directed networks, if agent i is a neighbor of agent j, j need not be a neighbor of i. In Watts-Strogatz networks we performed simulations to find the averaged number of final opinions and their distribution as a function of $\epsilon$ and of the network structural disorder. In directed networks exhibits a rich structure, being larger than in undirected networks for higher values of $\epsilon$, and smaller for lower values of $\epsilon$.Comment: 15 pages, 6 figure

Polarization Properties of the Solitons Generated in the Process of Pulse Breakup in Twisted Fiber Pumped by ns Pulses

Common optical fibers are randomly birefringent, and solitons formatting and traveling in them are randomly polarized. However, it is desirable to have solitons with a well-defined polarization. With pump relatively long pulses, the nonlinear effects of modulation instability (MI) and stimulated Raman scattering (SRS) are dominant at the initial stage of the process of supercontinuum (SC) generation; modulation instability results in pulse breakup and formation of short pulses that evolve finally to a bunch of solitons and dispersive waves. We do the research of the polarization of solitons formed by the pulse breakup process by the effect of modulation instability with pump pulses of nanoseconds in standard fiber (SMF-28) with circular birefringence introduced by fiber twist, and the twisted fiber mitigates the random linear birefringence. In this work, we found that polarization ellipticity of solitons is distributed randomly; nevertheless, the average polarization ellipticity is closer to the circular than the polarization ellipticity of the input pulse. In the experimental setup. 200 m of SMF-28 fiber twisted by 6 turns/m was used. We used 1 ns pulse to pump the fiber. The results showed that at circular polarization of the input pulse solitons at the fiber output have polarizations close to the circular, while in the fiber without twist, the soliton polarization was random

Hydrogen production and degradation of ciprofloxacin by Ag@TiO2-MoS2 Photocatalysts

The photocatalytic activity of silver-based catalysts containing different amounts of molybdenum disulfide (MoS2; 5, 10 and 20 wt.%) was evaluated by the degradation of the antibiotic ciprofloxacin and the production of hydrogen via water splitting. All the silver (Ag)-based catalysts degraded more than 70% of the antibiotic in 60 min. The catalyst that exhibited the best result was 5%Ag@TiO2-P25-5%MoS2, with ca. 91% of degradation. The control experiments and stability tests showed that photocatalysis was the degradation pathway and the selected silver-based catalysts were stable after seven cycles, with less than 2% loss of efficiency per cycle and less than 7% after seven cycles. The catalyst with the highest hydrogen production was 5%Ag@TiO2 NWs-20%MoS2, 1792 μmol/hg, at a wavelength of 400 nm. This amount was ca. 32 times greater than that obtained by the pristine titanium oxide nanowires catalyst. The enhancement was attributed to the high surface area of the catalysts, along with the synergism created by the silver nanoparticles and MoS2. All the catalysts were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), Brunauer–Emmett–Teller (BET) surface area analysis and energy dispersive X-ray spectroscopy (EDS)

Mutations related to Antiretroviral Resistance identified by ultra-deep sequencing in HIV-1 infected children under Structured Interruptions of HAART

Altres ajuts: CONACYT/GCPS/44519Although Structured Treatment Interruptions (STI) are currently not considered an alternative strategy for antiretroviral treatment, their true benefits and limitations have not been fully established. Some studies suggest the possibility of improving the quality of life of patients with this strategy; however, the information that has been obtained corresponds mostly to studies conducted in adults, with a lack of knowledge about its impact on children. Furthermore, mutations associated with antiretroviral resistance could be selected due to sub-therapeutic levels of HAART at each interruption period. Genotyping methods to determine the resistance profiles of the infecting viruses have become increasingly important for the management of patients under STI, thus low-abundance antiretroviral drug-resistant mutations (DRM's) at levels under limit of detection of conventional genotyping (<20% of quasispecies) could increase the risk of virologic failure. In this work, we analyzed the protease and reverse transcriptase regions of the pol gene by ultra-deep sequencing in pediatric patients under STI with the aim of determining the presence of high- and low-abundance DRM's in the viral rebounds generated by the STI. High-abundance mutations in protease and high- and low-abundance mutations in reverse transcriptase were detected but no one of these are directly associated with resistance to antiretroviral drugs. The results could suggest that the evaluated STI program is virologically safe, but strict and carefully planned studies, with greater numbers of patients and interruption/restart cycles, are still needed to evaluate the selection of DRM's during STI

Underwater imagery-study of sediment and fauna for habitat characterization in mud volcanoes of the Spanish margin (Gulf of Cádiz)

Habitat characterization using underwater images has been carried out in 4 mud volcanoes (Gazul, Almazán, St. Petersburg and Aveiro) and one mud volcano/diapir complex (Hespérides) located at the middle slope of the Spanish margin of the Gulf of Cádiz (360-1200m depth). A total of 126 species, mostly cnidarians, sponges, brachiopods, crustaceans and echinoderms and 19 habitats have been observed in the underwater images, including anoxic bottoms with cold seep fauna or remains (Siboglinum sp., Lucinoma asapheus, Solemya elarraichensis), bottoms with authigenic carbonates colonized by gorgonians and anthipatharians, extensive muddy bottoms with sea pens (Kophobelemnon sp., Protoptilum sp.) and bamboo corals (Isidella elongata) and cold-water coral banks (Madrepora oculata). Habitat type and distribution seem influenced by sedimentary features, presence of hard substrates with authigenic carbonates, seepage activity, depth and hydrodynamic conditions. Cold seep related species and heterotrophic species not directly linked to fluid venting represent seepage activity indicators and induce habitat and biodiversity differentiation among the fluid venting edifices