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• NiMoW and CoMoW trimetallic catalysts supported on SBA-15, Ti-SBA-15 and Zr-SBA-15. • NiMoW catalysts were more active than CoMoW ones in HDS of DBT and 4,6-dimethyl-DBT. • NiMoW/Zr-SBA-15 catalyst was the most active among all prepared trimetallic samples. • CoMoW/Zr-SBA-15 was the most selective for the C S bond cleavage in DBT and 4,6-DMDBT. SBA-15, Ti-SBA-15 and Zr-SBA-15 were used to prepare trimetallic CoMoW and NiMoW catalysts in order to inquire into the effect of the support's composition on the catalytic performance in deep hydrodesulfurization (HDS). Supports and catalysts were characterized by N 2 physisorption, X-ray diffraction, temperature-programmed reduction, scanning electron microscopy (SEM-EDX) and high-resolution transmission electron microscopy. The catalytic activity was determined in the simultaneous HDS of dibenzothiophene and 4,6-dimethyldibenzothiophene. The most important characteristics of the SBA-15 material were preserved in the titania and zirconia-containing supports and the trimetallic catalysts. The deposited metal oxide species (NiO, CoO, MoO 3 and WO 3) were well-dispersed. NiMoW catalysts were substantially more active in deep HDS than the corresponding CoMoW ones. Titania and zirconia addition to the supports resulted in higher HDS activity of NiMoW and CoMoW catalysts, being this effect larger for the Ni-promoted samples. The NiMoW/Zr-SBA-15 catalyst was the most active for the elimination of sulfur from both dibenzothiophene and 4,6-dimethyldibenzothiophene. Its activity was twice higher than that of the NiMoW/SBA-15 analog. This was attributed to the high dispersion of the deposited metal species in the sulfided NiMoW/Zr-SBA-15 sample. Regarding the catalysts' selectivity, it depended more strongly on the promoter used than on the support's chemical composition. [ABSTRACT FROM AUTHOR]

Gonadotropin releasing hormone (GnRH) synthesis and secretion regulates seasonal fertility. In the brain, the distribution of GnRH-positive neurons is diffuse, hindering efforts to monitor variations in its cellular and tissue levels. Here, we aim at assessing GnRH immunoreactivity in nuclei responsible for seasonal fertility regulation (SFR) within the posterior, anterior, and preoptic areas of the basal hypothalamus during estrous in ewes. We detected reaction products in the ventromedial basal hypothalamus in neurons, nerve fibers, non-neuronal immunoreactive bodies, and diffuse interstitial areas. Immunoreactivity correlated with the distribution of the main SFR nuclei in the arcuate, retrochiasmatic, periventricular, medial preoptic, supraoptic, and preoptic areas. By independent component analysis density segmentation and by interferential contrast, we identified GnRH non-neuronal positive bodies as microglial cells encapsulated within a dense halo of reaction products. These GnRH-positive microglial cells were distributed in patches and rows throughout the basal ventromedial hypothalamus, suggesting their role in paracrine or juxtacrine signaling. Moreover, as shown by ionized calcium-binding adaptor molecule 1 (IBA1) immunocytochemistry, the distribution of GnRH reaction products overlapped with the microglial dense reactive zones. Therefore, our findings support the assertion that a combined densitometric analysis of GnRH and IBA1 immunocytochemistry enables activity mapping for monitoring seasonal changes following experimental interventions. • GnRH reaction products overlap with areas of reactive microglia in the basal ventromedial hypothalamus of ewes. • GnRH-positive microglial cells support their role in activity-dependent juxtacrine signaling. • Comparative densitometric mapping of GnRH and IBA1 may be a suitable method for monitoring seasonal changes. [ABSTRACT FROM AUTHOR]

Hydrogen storage in chemical bonds such as ammonia is an attractive alternative to physical hydrogen storage if a sustainable and efficient catalyst can be designed for the release of COx-free hydrogen on demand. This paper presents a systematic study for the design of cobalt-based catalysts, moving away from scare Ru-based systems. It demonstrates the importance of the preparation method of cobalt-based catalysts not only to tune the size of the active species and their interaction with the support but also in the promotion of active species. Cobalt supported on titanate nanotubes via an ion-exchange method leads to the incorporation of the cobalt into the crystal structure of the titanates facilitating the formation of unreducible cobalt titanate species with a detrimental effect on the reactivity, and the thermal stability of the titanate support. Considerably higher reactivities can be achieved by loading cobalt via deposition-precipitation with NaOH method, leading to the formation of reducible cobalt particles on the surface of the titanate nanorods support. In this case, the rate of reaction is inversely related to the cobalt particle size, pointing out the key effect of particle size of cobalt-based catalyst for the hydrogen production in ammonia decomposition. Although the activities reported here for cobalt-based catalysts are still below those of the state-of-the-art ruthenium counterpart systems, this work provides unique insights for the future development of sustainable catalysts for the use of ammonia as hydrogen vector. • High H 2 production from ammonia on cobalt-based catalysts. • Guidance for future cobalt-based catalysts development to replace scarce Ru. • Cobalt particle size plays a key parameter on ammonia decomposition activity. • Cobalt catalyst preparation method affects its size and interaction with support. • Strong-cobalt support interaction leads to formation of unreducible and inactive species. [ABSTRACT FROM AUTHOR]

• The Mexican Carbon Capture and Storage Platform is a boundary object to overcome language and context-related challenges for CCS technology communication. • Digital communication platforms connect contexts, stakeholders, and disciplines. • CCS assimilation requires effective communication and collaboration strategies. • Science and art in digital space help transfer and translate knowledge. Carbon Capture and Storage (CCS) is a technology identified as a potential solution to mitigate climate change by reducing carbon emissions from large-scale emitters. If CCS is expected to be adopted globally, transparent and reliable data and information must be readily attainable to all stakeholders to support the technology choice and decision-making process. The implementation of CCS requires effective communication and collaboration strategies. Still, materials and communication platforms to inform stakeholders about the potential and contribution of CCS are predominantly accessible in English since ongoing projects are mainly located in English-speaking countries. The Mexican Carbon Capture and Storage platform (MeCCS) was developed as a digital sharing and learning space for national stakeholders to obtain and expand their knowledge about CCS technology in Spanish. It was constructed as a boundary object (BO) to bridge different communities and disciplines, facilitating communication, understanding, and cooperation. The platform includes diverse elements that combine science and art to produce dissemination materials for different audiences to help build critical thinking and inform them about CCS technology. The platform confirmed its capacity to transfer and translate knowledge one year after its launch. It also served to connect different audiences in Mexico and globally and identify further areas of research and CCS-related efforts. [ABSTRACT FROM AUTHOR]

A multiaxial fatigue criterion recently developed by the authors for 2D conditions is extended here to 3D situations and applied to predict fatigue damage in rail welded joints with the help of an explicit finite element model. Contact theory and axle box acceleration response in frequency domain are used to validate the finite element model. The influence of depth and length of the welded joints is analyzed. It is found that fatigue damage is more severe with shorter and deeper welded joints. When the length of the welded joints is less than 150 mm, fatigue damage is greatly increased with the increasing of the depth. When the depth is less than 0.1 mm, fatigue damage is not relevant, regardless of the length. When the depth is greater than 0.3 mm, fatigue damage increases significantly with the decreasing of the joint length, especially when the length is less than 150 mm. When the welded joints are long enough, the depth restriction can be relaxed. This work can provide guidance and theoretical support for maintenance and repair of rail welded joints. [ABSTRACT FROM AUTHOR]

This work presents a proposal for enhancing CO 2 capture over lithium cuprate (Li 2 CuO 2 ) by alkaline carbonates addition. Lithium cuprate was synthesized via solid-state reaction. Subsequently, portions of Li 2 CuO 2 were mechanically mixed with 10 wt% of potassium carbonate (K 2 CO 3 ), sodium carbonate (Na 2 CO 3 ) or equal amounts of both carbonates (5–5 wt%). All samples were characterized by several techniques and then CO 2 chemisorption process was evaluated on different dynamic and isothermal conditions. The presence of K and/or Na carbonates preserves the primary properties of pristine Li 2 CuO 2 , such as crystalline phase (DRX) and microstructure (SEM), also allowing to increase textural properties (N 2 physisorption) and modifying CO 2 desorption abilities (TPD), in comparison with pure material. In general, carbonates addition induces some changes during CO 2 chemisorption, depending on the type of carbonate used. On the isothermal tests, it was observed that between 400 and 600 °C the sample containing both carbonates presented the best capture performance, capturing between 25.7 and 31.8 wt% of CO 2 (63.9–79.1% of efficiency). On the other hand, at 700 °C, Na-Li 2 CuO 2 sample presented the best capture ability, capturing 30.6 wt% of CO 2 (76.1% of efficiency). Meanwhile at 650 °C, K-Li 2 CuO 2 presented the highest sorption capacity with 40.4 wt% of CO 2 captured, which represents ∼100% of efficiency. The above results showed that in the same thermal conditions, samples modified with alkaline carbonates improved the CO 2 capture process. This enhancement was attributed to the formation of eutectic phases (observed in DSC analysis) between sodium and potassium carbonates added mechanically and lithium carbonate (Li 2 CO 3 ) formed as result of CO 2 chemisorption process. Finally, it was observed that carbonate addition is a feasible way to increase CO 2 capture in Li 2 CuO 2 material by means of eutectic phase formation. [ABSTRACT FROM AUTHOR]

There is an increasing interest in the use of GPU technologies for real time analysis in fusion devices. The availability of high bandwidth interfaces has made them a very cost effective alternative not only for high volume data analysis or simulation, and commercial products are available for some interest areas. However from the point of view of their application in real time scenarios, there are still some issues under analysis, such as the possibility to improve the data throughput inside a discrete system consisting of data acquisition devices (DAQ) and GPUs. This paper addresses the possibility of using peer to peer data communication between DAQ devices and GPUs sharing the same PCIexpress bus to implement continuous real time acquisition and processing systems where data transfers require minimum CPU intervention. This technology eliminates unnecessary system memory copies and lowers CPU overhead, avoiding bottleneck when the system uses the main system memory. [ABSTRACT FROM AUTHOR]

In this paper, the relativistic BGK model is studied. The Jüttner function is presented as the relativistic counterpart of the local Maxwellian equilibrium in the classical case. By linearization around this equilibrium, we obtain a linearized relativistic BGK model and study their time decay at infinity. Finally, existence and asymptotic behavior of close-to-equilibrium solutions of the whole nonlinear relativistic BGK model are proved. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new kinetic consecutive reaction model for CO 2 capture on Na 2 ZrO 3 is proposed. • Different CO 2 flow rates were used for analyzing the mathematical model. • This model incorporates the low-temperature CO 2 sorption-desorption step. • The results are compared to previously reported models using other alkaline ceramics. • The whole CO 2 capture is discussed, at different temperatures and flow rates. In this work, it is presented a kinetic study for CO 2 capture on Na 2 ZrO 3 as a function of temperature (250−550 °C) and CO 2 flow rate (5, 60, and 120 mL/min). We discuss the relevance of a new kinetic model able to fit the experimental data and propose a consecutive reaction model for CO 2 capture under low, moderate, and high CO 2 flow rates. The proposed model considers that a Na 2 CO 3 –ZrO 2 layer is formed at the particle surface level, and then, the capture process is later enhanced by Na+ ions diffusion, but its improvement depends entirely on the surface capture. This kinetic approach allowed a better fit for CO 2 capture results, describing well the variations obtained as a function of the different flow rates tested between 250 and 550 °C. Thermogravimetric and kinetic data showed that the CO 2 capture was benefited as the CO 2 flow rate increased from 5 to 120 mL/min. However, high flow rates (60 and 120 mL/min) achieved similar capture efficiencies (Ɛ ≈ 90 %), only once the CO 2 sorption-desorption equilibrium was reached. In addition, through the Eyring model analysis, the activated state energy was calculated, being within the range of 0.84 and 1.20 eV for the surface capture and between 0.89 and 1.02 eV for bulk capture (related to Na+ diffusion). In the final section, it was discussed the CO 2 sorption-desorption process takes place at both, low temperature and flow rate, and how such a process inhibits or triggers high-temperature CO 2 capture. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, a comparison study of the NiMo hydrodesulfurization catalysts supported on different types of silica supports (nanostructured supports of MCM-41 and SBA-15-types and commercial amorphous silica) and the same ones modified by TiO2 grafting was undertaken. The aim of this study was to inquire on the effect of the characteristics of the primary silica supports on the activity and selectivity of the NiMo catalysts modified with titania in deep HDS. Supports and catalysts were characterized by nitrogen physisorption, small-angle and powder XRD, TPR, UV–vis DRS, and HRTEM, and tested in the simultaneous HDS of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT). It was found that titania grafting on all silica supports resulted in a slight decrease of BET surface area and total pore volume. However, the characteristic p6mm hexagonal pore arrangement of the used nanostructured silica materials was not affected. Powder X-ray diffraction pointed out a good dispersion of Mo and Ni oxide species in all prepared catalysts. TPR characterization of the NiMo catalysts revealed some increase in the metal-support interaction after titania grafting on the silica surface. Further DRS characterization indicated that the best dispersion of Mo oxide species was obtained on the TiSBA-15 support. Titania addition to the silica supports also produced an increase in the dispersion of the sulfided NiMo phase, which was more marked for SBA-15 and commercial silica supports than for the MCM-41 (HRTEM). In line with the characterization results, titania addition to all silica supports resulted in an increase in the HDS activity of NiMo catalysts. However, this increase was smaller for the MCM-41 support than for the SBA-15 and amorphous silica supports used. The most active NiMo/Ti-SBA-15 catalyst resulted to be significantly more active (∼40%) than the reference NiMo/γ-Al2O3 catalyst in HDS of 4,6-DMDBT. [Copyright &y& Elsevier]

Abstract: Congestion, pollution, security, parking, noise, and many other problems derived from vehicular traffic are present every day in most cities around the world. The growing number of traffic lights that control the vehicular flow requires a complex scheduling, and hence, automatic systems are indispensable nowadays for optimally tackling this task. In this work, we propose a Swarm Intelligence approach to find successful cycle programs of traffic lights. Using a microscopic traffic simulator, the solutions obtained by our algorithm are evaluated in the context of two large and heterogeneous metropolitan areas located in the cities of Málaga and Sevilla (in Spain). In comparison with cycle programs predefined by experts (close to real ones), our proposal obtains significant profits in terms of two main indicators: the number of vehicles that reach their destinations on time and the global trip time. [Copyright &y& Elsevier]

Abstract: The plasma electron temperature has been estimated starting from the spectroscopic analysis of the optical emission of the laser-generated plasma plume during quite diverse stainless steel welding procedures (c.w. CO2 and pulsed Nd:YAG). Although the optical emissions present different spectral features, a discrete contribution of several iron lines can be highlighted in both types of welding. We have found that the electron temperature decreases as the laser power is enhanced, in static as well as dynamic conditions. Such a result could be useful to develop a closed loop control system of the weld penetration depth. [Copyright &y& Elsevier]

Abstract: The emerging field of vehicular ad hoc networks (VANETs) deals with a set of communicating vehicles which are able to spontaneously interconnect without any pre-existing infrastructure. In such kind of networks, it is crucial to make an optimal configuration of the communication protocols previously to the final network deployment. This way, a human designer can obtain an optimal QoS of the network beforehand. The problem we consider in this work lies in configuring the File Transfer protocol Configuration (FTC) with the aim of optimizing the transmission time, the number of lost packets, and the amount of data transferred in realistic VANET scenarios. We face the FTC with five representative state-of-the-art optimization techniques and compare their performance. These algorithms are: Particle Swarm Optimization (PSO), Differential Evolution (DE), Genetic Algorithm (GA), Evolutionary Strategy (ES), and Simulated Annealing (SA). For our tests, two typical environment instances of VANETs for Urban and Highway scenarios have been defined. The experiments using ns- 2 (a well-known realistic VANET simulator) reveal that PSO outperforms all the compared algorithms for both studied VANET instances. [Copyright &y& Elsevier]

Abstract: Titanium dioxide was obtained in its pure form (TiO2) and in the presence of urea (u-TiO2) and thiourea (t-TiO2) using the sol–gel technique. The obtained powders were characterized by BET surface area analysis, Infrared Spectroscopy, Diffuse Reflectance Spectroscopy and the Rietveld refinement of XRD measurements. All the prepared catalysts show high anatase content (>99%). The a and b-cell parameters of anatase increase in the order TiO2 u-TiO2 >TiO2. The photocatalytic activities of the samples were determined on flumequine under solar-simulated irradiation. The most active catalysts were u-TiO2 and t-TiO2, reaching values over 90% of flumequine degradation after 15min irradiation, compared with values of 55% for the pure TiO2 catalyst. Changing simultaneously the catalyst amount (t-TiO2) and pH, multivariate analysis using the response surface methodology was used to determine the roughly optimal conditions for flumequine degradation. The optimized conditions found were pH below 7 and a catalyst amount of 1.6gL−1. [Copyright &y& Elsevier]

Abstract: The protective capabilities of three Leishmania recombinant proteins – histone 1 (H1) and hydrophilic acylated surface protein B1 (HASPB1) immunized singly, or together as a protein cocktail vaccine with Montanide™, and the polyprotein MML immunized with MPL®-SE adjuvant – were assessed in beagle dogs. Clinical examination of the dogs was carried out periodically under blinded conditions and the condition of the dogs defined as asymptomatic or symptomatic. At the end of the trial, we were able to confirm that following infection with L. infantum promastigotes, five out of eight dogs immunized with H1 Montanide™, and four out of eight dogs immunized with either the combination of HASPB1 with Montanide™ or the combination of H1+HASPB1 with Montanide™, remained free of clinical signs, compared with two out of seven dogs immunized with the polyprotein MML and adjuvant MPL®-SE, and two out of eight dogs in the control group. The results demonstrate that HASPB1 and H1 antigens in combination with Montanide™ were able to induce partial protection against canine leishmaniasis, even under extreme experimental challenge conditions. [Copyright &y& Elsevier]

Abstract: Titanium oxide -based ceramics have many desirable and potential applications. Their mechanical properties are strongly affected by composition and microstructure, and can thus be tailored. The optical properties of are useful, being colorless, transparent, and possessing a high refractive index. These properties and the ability to tailor the structure make -based ceramics suitable for a wide range of applications. Interest in titanium oxide-based ceramics has increased considerably in recent years as possible thermoluminescence (TL) dosimeters which could be used in a wide variety of research activities and applications of ionizing radiation dosimetry. The aim of this work is to investigate some dosimetric properties of manganese doped titanium oxide nanopowder concerning the TL phenomenon related to its structural, morphological, and luminescent characteristics. Powder of was prepared using a co-precipitation method from titanium oxysulfate–sulfuric acid complex and . Formation of the compound was confirmed by studying the X-ray diffraction patterns. Diffraction patterns obtained suggested a mixture of anatase and rutile structure of the powder analyzed. Assuming the particles are stress-free, the size was estimated from a single diffraction peak using Scherrer''s equation. Powder with the average nanopolycrystalline sizes from up to about was obtained. The glow curve of nanopowder exposed to gamma radiation exhibited one main peak centered at and a lower intensity peak at about . The intensity of the main peak increases as the dose increases. TL glow curve intensity of powder submitted to was found to be more intense than that of the amorphous material, with the intensity increasing with the increase of crystallization temperature. [Copyright &y& Elsevier]

Abstract: The effect of various chemical modifiers 0.5gl−1 Pd, 1% (w/v) Ni, 0.5gl−1 Pd+1% (w/v) Ni and 1.0gl−1 Pd on the measurement of selenium in soil aqua regia extracts, by ZETAAS, is described. Two Certified Reference Materials (CRMs) RTC-CRM 023-050 and RTC-CRM 025-050 were used for this study. Pyrolysis and atomization curves were obtained for each chemical modifier and their optimal values were assessed. By using standard addition as calibration method, accurate results were obtained for all the chemical modifiers studied. The precision was similar for both CRMs, with a maximum value of 7.5% R.S.D. The limits of detection and quantification for selenium in the soil extracts (n =10) were 3.0 and 6.0μgl−1, respectively. The characteristic mass of selenium is assessed as 10pg. The use of aqua regia as extractant gave quantitative results for selenium in the CRMs assayed. [Copyright &y& Elsevier]