Comparison between thermophysical and tribological properties of two engine lubricant additives: electrochemically exfoliated graphene and molybdenum disulfide nanoplatelets.

Recently graphene and other 2D materials were suggested as nano additives to enhance the performance of nanolubricants and reducing friction and wear-related failures in moving mechanical parts. Nevertheless, to our knowledge there are no previous studies on electrochemical exfoliated nanomaterials as lubricant additives. In this work, engine oil-based nanolubricants were developed via two-steps method using two different 2D nanomaterials: a carbon-based nano additive, graphene nanoplatelets (GNP) and a sulphide nanomaterial, molybdenum disulfide (MoS2) nanoplatelets (MSNP). The influence of these nano additives on the thermophysical properties of the nanolubricants, such as viscosity index, density and wettability, was investigated. The unique features of the electrochemical exfoliated GNP and MSNP allow the formulation of nanolubricant with unusual thermophysical properties. Both the viscosity and density of the nanolubricants decreased by increasing the nanoplatelets loading. The effect of the nano additives loading and temperature on the tribological properties of nanolubricants was investigated using two different test configurations: reciprocating ball-on-plate and rotational ball-on-three-pins. The tribological specimens were analysed by scanning electron microscopy (SEM) and 3D profiler in order to evaluate the wear. The results showed significant improvement in the antifriction and anti-wear properties, for the 2D-materials-based nanolubricants as compared with the engine oil, using different contact conditions. For the reciprocal friction tests, maximum friction and worn area reductions of 20% and 22% were achieved for the concentrations of 0.10 wt% and 0.20 wt% GNP, respectively. Besides, the best anti-wear performance was found for the nanolubricant containing 0.05 wt% MSNP in rotational configuration test, with reductions of 42% and 60% in the scar width and depth, respectively, with respect to the engine oil.

Modeling of the Production of Lipid Microparticles Using PGSS® Technique.

Solid lipid microparticles (SLMPs) are attractive carriers as delivery systems as they are stable, easy to manufacture and can provide controlled release of bioactive agents and increase their efficacy and/or safety. Particles from Gas-Saturated Solutions (PGSS®) technique is a solvent-free technology to produce SLMPs, which involves the use of supercritical CO2 (scCO2) at mild pressures and temperatures for the melting of lipids and atomization into particles. The determination of the key processing variables is crucial in PGSS® technique to obtain reliable and reproducible microparticles, therefore the modelling of SLMPs production process and variables control are of great interest to obtain quality therapeutic systems. In this work, the melting point depression of a commercial lipid (glyceryl monostearate, GMS) under compressed CO2 was studied using view cell experiments. Based on an unconstrained D-optimal design for three variables (nozzle diameter, temperature and pressure), SLMPs were produced using the PGSS® technique. The yield of production was registered and the particles characterized in terms of particle size distribution. Variable modeling was carried out using artificial neural networks and fuzzy logic integrated into neurofuzzy software. Modeling results highlight the main effect of temperature to tune the mean diameter SLMPs, whereas the pressure-nozzle diameter interaction is the main responsible in the SLMPs size distribution and in the PGSS® production yield.

Fundamentos teóricos de la preparación del estudiante de Estomatología en función de la educación para la salud bucal periodontal / Theoretical foundations of the dentistry students preparation in terms of education for the periodontal oral health

RESUMEN Introducción: La aspiración de egresar un estomatólogo general suficientemente preparado para resolver los problemas de salud bucal periodontal más generales y prevalentes es una exigencia social que se revela en el actual plan de estudio de la carrera de Estomatología. Objetivo: Elaborar unos referentes teóricos de la preparación del estudiante de Estomatología en función de la educación para la salud bucal periodontal. Método: De enero a julio de 2020, en la Facultad de Estomatología de la Universidad de Ciencias Médicas Guantánamo se realizó una revisión narrativa sobre el tema a través de una búsqueda en bases de datos electrónicas (Biblioteca Virtual en Salud, LILACS, PubMed, SciELO, REDALYC, Scopus). Se sistematizaron referentes teóricos que sustentan la preparación del estudiante de Estomatología en función de la educación para la salud bucal periodontal. Conclusiones: Se evidencia la necesidad de esta preparación dada su implicación en el modo de actuación profesional para una Atención Bucal Periodontal Integral. Las bases para esta finalidad emergen de la conjugación armoniosa de referentes filosóficos, sociológicos, legales, psicológicos, pedagógicos y didácticos en función de la práctica de la profesión.

ABSTRACT Introduction: The aim to graduate a general dentist with a high standard in knowledge to solve the most general and prevalent periodontal oral health issues is a social demand that is revealed in the current study program of dentistry major. Objective: To elaborate some theoretical references concerning dentistry student preparation in terms of education for periodontal oral health. Method: From January to July 2020, at the Facultad de Estomatología in the Universidad de Ciencias Médicas Guantanamo, a narrative review on the subject was carried out through a search in electronic databases (Virtual Health Library, LILACS, PubMed, SciELO, REDALYC, Scopus). It was systematized all the theoretical references that support the preparation of the dentistry students in terms of education for periodontal oral health. Conclusions: It is evident the necessity of this type of training due to its implication in the way to the best professional performance for an integral oral care. The foundations for achieving this goal emerge from the harmonious conjugation of philosophical, sociological, legal, psychological, pedagogical and didactic referents, in accordance to the practice of the profession.

Tribological Behavior of Nanolubricants Based on Coated Magnetic Nanoparticles and Trimethylolpropane Trioleate Base Oil.

The main task of this work is to study the tribological performance of nanolubricants formed by trimethylolpropane trioleate (TMPTO) base oil with magnetic nanoparticles coated with oleic acid: Fe3O4 of two sizes 6.3 nm and 10 nm, and Nd alloy compound of 19 nm. Coated nanoparticles (NPs) were synthesized via chemical co-precipitation or thermal decomposition by adsorption with oleic acid in the same step. Three nanodispersions of TMPTO of 0.015 wt% of each NP were prepared, which were stable for at least 11 months. Two different types of tribological tests were carried out: pure sliding conditions and rolling conditions (5% slide to roll ratio). With the aim of analyzing the wear by means of the wear scar diameter (WSD), the wear track depth and the volume of the wear track produced after the first type of the tribological tests, a 3D optical profiler was used. The best tribological performance was found for the Nd alloy compound nanodispersion, with reductions of 29% and 67% in friction and WSD, respectively, in comparison with TMPTO. On the other hand, rolling conditions tests were utilized to study friction and film thickness of nanolubricants, determining that Fe3O4 (6.3 nm) nanolubricant reduces friction in comparison to TMPTO.

Creation Process of the Digital Platform to Foster Healthy and Active Aging: enbuenaedad.

Andalusia is a region in the south of Spain with 8,4 million inhabitants of which 1,3 million are over 65 years old. Andalusia has been recognized as Reference Site by the European Commission within the European Innovation Partnership on Active and Healthy Aging. The Regional Ministry of Health of Andalusia has put in place strategies to promote healthy and active aging. One of these strategies is enbuenaedad, a digital platform which main aim is to foster active and healthy aging. The target audience is people over 55 years old, caregivers of older adults, as well as health and other key professionals who work with this population. Content sections are inspired in the three pillars of the World Health Organization (WHO) policy framework for active and healthy aging: health, participation, and security, but introducing an additional one which is lifelong learning. One of the strengths of this platform is the creation process. Using a co-thinking design, all target groups get voice under the umbrella of empathy and are empowered by providing support, training, knowledge, and best practices. For its development, dissemination, maintenance, and improvement, the project advocates the unavoidable participation of key stakeholders representing all sectors involved: The Senior Council of Andalusia; Primary Health Care professionals; local authorities; Guadalinfo agents; Permanent Adult Education; and Active Participation Centers. Quantitative and qualitative data obtained within the process support this project. Since its launching, 10,779 users have registered to the platform with more than 157,000 visits. Focusing on WHO four pillars on active and healthy aging Enbuenaedad is based on, preliminary results show effectiveness regarding participation and social interaction. Furthermore, achieving high participation coverage is a necessary but not sufficient input to the provision of adequate approach to older people. More comprehensive evaluation of the four pillars must be taken to ensure a holistic approach. A challenge is a cooperation between three traditionally independent sectors, cooperative work between health, social services, and education is crucial for the future sustainability of this intervention.

Experimental Convection Heat Transfer Analysis of a Nano-Enhanced Industrial Coolant.

Convection heat transfer coefficients and pressure drops of four functionalized graphene nanoplatelet nanofluids based on the commercial coolant Havoline® XLC Pre-mixed 50/50 were experimentally determined to assess its thermal performance. The potential heat transfer enhancement produced by nanofluids could play an important role in increasing the efficiency of cooling systems. Particularly in wind power, the increasing size of the wind turbines, up to 10 MW nowadays, requires sophisticated liquid cooling systems to keep the nominal temperature conditions and protect the components from temperature degradation and hazardous environment in off-shore wind parks. The effect of nanoadditive loading, temperature and Reynolds number in convection heat transfer coefficients and pressure drops is discussed. A dimensionless analysis of the results is carried out and empirical correlations for the Nusselt number and Darcy friction factor are proposed. A maximum enhancement in the convection heat transfer coefficient of 7% was found for the nanofluid with nanoadditive loading of 0.25 wt %. Contrarily, no enhancement was found for the nanofluids of higher functionalized graphene nanoplatelet mass fraction.

Defence cascade in Verticillium-infected grafted tomato.

In tomato the Ve1-gene provides resistance to the vascular pathogen, Verticillium dahliae, race 1; ve1 plants are susceptible. Reciprocal grafts of resistant and susceptible tomato near-isolines were used to examine proteomic changes and, in particular, the effect of the Ve1-gene on the defence/stress protein cascade induced during Verticillium wilt. Based on label-free LC-MS, the results indicate that this defence response is cell-specific, correlates with overall fungal colonization and is mitigated by Ve1 function. The influence of the Ve1-gene in resistant tissues, however, is not actually transferred to susceptible tissues in the grafted plant.

West Nile virus outbreak in humans and epidemiological surveillance, west Andalusia, Spain, 2016.

In Andalusia, Spain, West Nile virus (WNV) surveillance takes place from April to November, during the active vector period. Within this area seroconversion to this virus was evidenced in wild birds in 2004, affecting horses and two humans for the first time in 2010. Since 2010, the virus has been isolated every year in horses, and national and regional surveillance plans have been updated with the epidemiological changes found. WNV is spreading rapidly throughout southern Europe and has caused outbreaks in humans. Here we describe the second WNV outbreak in humans in Andalusia, with three confirmed cases, which occurred between August and September 2016, and the measures carried out to control it. Surveillance during the transmission season is essential to monitor and ensure prompt identification of any outbreaks.

PEG 400-Based Phase Change Materials Nano-Enhanced with Functionalized Graphene Nanoplatelets.

This study presents new Nano-enhanced Phase Change Materials, NePCMs, formulated as dispersions of functionalized graphene nanoplatelets in a poly(ethylene glycol) with a mass-average molecular mass of 400 g·mol-1 for possible use in Thermal Energy Storage. Morphology, functionalization, purity, molecular mass and thermal stability of the graphene nanomaterial and/or the poly(ethylene glycol) were characterized. Design parameters of NePCMs were defined on the basis of a temporal stability study of nanoplatelet dispersions using dynamic light scattering. Influence of graphene loading on solid-liquid phase change transition temperature, latent heat of fusion, isobaric heat capacity, thermal conductivity, density, isobaric thermal expansivity, thermal diffusivity and dynamic viscosity were also investigated for designed dispersions. Graphene nanoplatelet loading leads to thermal conductivity enhancements up to 23% while the crystallization temperature reduces up to in 4 K. Finally, the heat storage capacities of base fluid and new designed NePCMs were examined by means of the thermophysical properties through Stefan and Rayleigh numbers. Functionalized graphene nanoplatelets leads to a slight increase in the Stefan number.

Segmental intestinal necrosis in a young patient.

Segmental ischemic colitis is an uncommon disease in young patients, being usually associated to drug abuse, infectious or autoimmune diseases. We present a case that, in spite of a complete diagnostic study, had repeatedly two attacks of intestinal necrosis during his admission.

[Health impact assessment methodology for urban planning projects in Andalusia (Spain)]. / Metodología de la valoración del impacto en salud de instrumentos de planeamiento urbanístico en Andalucía.

OBJECTIVE: To describe the tool developed in Andalusia (Spain) to conduct an analysis and prospective assessment of health impacts from urban planning projects as well as the process followed to design it. METHOD: On the one hand, direct and indirect relationships between urban setting and health were identified in light of the best scientific evidence available; and, on the other hand, methods and tools in impact assessment were reviewed. After the design of the tool, it was tested via both internal and external validation processes (meetings, workshops and interviews with key informants). RESULTS: The tool consists of seven phases, structured in two stages. A first descriptive stage shows how to obtain information about goals, objectives and general points pertaining the project and also to characterise the potentially affected population. The second one indicates, in several phases, how to identify and sort out potential impacts from the project using different supporting tools. CONCLUSIONS: Both in the testing phase and through its implementation since the entry into force of Andalusian Decree 169/2014 (16 June 2015) and forced all urban planning projects to be subjected to an Health Impact Assessment, this methodology has proved responsive, identifying major potential health impacts from the measures included in those projects. However, the tool has been shaped as a living tool and will be adapted in line with the experience acquired in its use.

Spontaneous rupture of a liver hemangioma. A case report.

Spontaneous rupture of a liver hemangioma is a very uncommon disease, but extremely seriousness because it is associated to a 75% of mortality caused by hipovolemic shock. A case of an spontaneous rupture of liver hemangioma, which was previously unknow, is presented.

[A strategy for institutionalisation of health impact assessment in Andalusia (Spain)]. / Institucionalización de la evaluación del impacto en la salud en Andalucía.

Health impact assessment (HIA) aims to incorporate people's health and wellbeing as a key feature in policy-making. Many authors believe that HIA might be systematically integrated into all decision-making processes as a way to achieve that goal. To that end, there is need to overcome a number of challenges, including the fact that Andalusia (Spain) has made HIA compulsory by law, the need for awareness of all public sectors whose decisions might have substantial impacts on health and for a methodology that would enable a comprehensive approach to health determinants and inequalities, and the training of both the public health staff and professional sectors responsible for its application. In Andalusia, a law provides mandatory and binding health impact reports for most authorisation procedures in different areas: from sectoral plans to urban planning schemes, and especially projects subject to environmental assessment. Implementation of this law has required its integration into authorisation procedures, the training of interdisciplinary working groups in public health, the preparation of technical guidelines, and the organisation of dissemination and training seminars for developers.

[Outbreaks of Measles in Andalusia, Spain, during the Period 2010-2015]. / Brotes epidémicos de sarampión en Andalucía durante el período 2010-2015.

The Andalusian Surveillance Epidemiological System (SVEA) controls and investigates any notification of measles or any other communicable disease. The aim of this article is to describe the epidemiological characteristics of measles outbreaks occurred in Andalusia in the last five years (2010-2015) and their control measures. In this period three outbreaks were reported: the first one started in Granada in 2010 in a community of objectors to vaccination. Control measures of measles protocol of SVEA were adopted (case isolation, identification and contacts immunization), including judicial measures among the group who refused the vaccination. The second outbreak started in Seville in 2011 in an "area in need of social transformation" and it spread throughout the region. The routine vaccination coverage review was introduced within the surveillance system after those outbreaks, identifying the most vulnerable people. During the first six months of 2015, a small outbreak, of 15 cases, occurred in Granada. The outbreak was controlled mainly due to the early intervention, the health measures adopted in the schools and health centres involved and the high vaccination coverage achieved in the population.

Thermodynamic scaling of the shear viscosity of Mie n-6 fluids and their binary mixtures.

In this work, we have evaluated the applicability of the so-called thermodynamic scaling and the isomorph frame to describe the shear viscosity of Mie n-6 fluids of varying repulsive exponents (n = 8, 12, 18, 24, and 36). Furthermore, the effectiveness of the thermodynamic scaling to deal with binary mixtures of Mie n-6 fluids has been explored as well. To generate the viscosity database of these fluids, extensive non-equilibrium molecular dynamics simulations have been performed for various thermodynamic conditions. Then, a systematic approach has been used to determine the gamma exponent value (γ) characteristic of the thermodynamic scaling approach for each system. In addition, the applicability of the isomorph theory with a density dependent gamma has been confirmed in pure fluids. In both pure fluids and mixtures, it has been found that the thermodynamic scaling with a constant gamma is sufficient to correlate the viscosity data on a large range of thermodynamic conditions covering liquid and supercritical states as long as the density is not too high. Interestingly, it has been obtained that, in pure fluids, the value of γ is directly proportional to the repulsive exponent of the Mie potential. Finally, it has been found that the value of γ in mixtures can be deduced from those of the pure component using a simple logarithmic mixing rule.

Ionic liquids based on phosphonium cations as neat lubricants or lubricant additives for a steel/steel contact.

After doing several miscibility essays with eight ionic liquids (ILs) and four base oils, the ILs tri(butyl)ethylphosphonium diethylphosphate [P4,4,4,2][C2C2PO4] and trihexyl(tetradecyl)phosphonium tris(pentafluoroethyl)trifluorophosphate [P6,6,6,14][(C2F5)3PF3] were selected to be studied as lubricant additives. The neat IL [P4,4,4,2][C2C2PO4], the base oils, and several blends were characterized in terms of density, viscosity, and thermal stability. The tribological performance of the miscible base oil/IL blends (1 wt %) and the neat [P4,4,4,2][C2C2PO4] were evaluated for the lubrication of an AISI 420 steel-100Cr6 steel contact pair. The friction coefficients and wear volumes obtained are also compared with those corresponding to the pure base oils and their mixtures with conventional additive zinc dialkyldithiophosphate (ZDDP). As neat lubricants, [P4,4,4,2][C2C2PO4] showed the best antifriction ability, whereas in terms of wear, better results were obtained with [P6,6,6,14][(C2F5)3PF3]. However, higher improvements in both friction and wear were found for blends containing [P4,4,4,2][C2C2PO4]. XPS analyses of the worn surfaces lubricated with these mixtures indicated the presence of phosphorus in the tribofilm formed on the wear track. However, this compound was slightly detected on tribosamples lubricated with blends containing [P6,6,6,14][(C2F5)3PF3].

Bulk and liquid-vapor interface of pyrrolidinium-based ionic liquids: a molecular simulation study.

Using molecular dynamics simulations, we have studied the structure of three 1-butyl-1-methylpyrrolidinium ionic liquids whose anions are triflate, bis(trifluoromethanesulfonyl)imide, and tris(pentafluoroethyl)trifluorophosphate. The structure of the bulk phase of the three ionic liquids has been interpreted using radial and spatial distribution functions and structure factors that allows us to characterize the morphology of the polar and nonpolar domains present in this family of liquids. The size of the polar regions depends on the anion size, whereas the morphology of the nonpolar domains is anion-independent. Furthermore, the surface ordering properties of the ionic liquids and charge and density profiles were also studied using molecular simulations. The surface tension of the liquid-vapor interfaces of these ionic liquids was also predicted from our molecular simulations. In addition, microscopic structural analysis of orientational ordering at the interface and density profiles along the direction normal to the interface suggest that the alkyl chains of the cation tend to protrude toward the vacuum, and the presence of the interface leads to a strong organization of the liquid phase in the region close to the interface. In the interfacial area, the polar regions of the ionic liquids are more structured than those in the bulk phase, whereas the opposite behavior is observed for the nonpolar regions.