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Alkali-activated materials (AAM) and hybrid cements (HC) have become sustainable alternatives to Portland cement (PC) due to their low carbon footprint. The main differences between AAM and HC lie in their content of clinker (none in the AAM and usually lower than 30% for HCs) and the type of activator used (strong alkaline solutions for AAM and small amounts of solid alkalis for HC). Durability problems related with microstructural changes due to decalcification and leaching of the cementitious paste have been well researched for PC pastes, but it is still not well known for AAM and HC. The present work aims to study the leaching process for cement pastes of both types of sustainable pastes. Blast furnace slag (BFS) was selected as a precursor to manufacture hybrid slag (HS) pastes and alkali-activated slag (AAS) pastes. A commercial CEM IV was selected as reference material. A 6 M NH4NO3 solution was used to accelerate leaching kinetics. After 28 days of immersion, the mineralogical and microstructural changes were evaluated. Results show that AAS pastes exhibited the highest leaching resistance of all the pastes under study, due to the absence of portlandite and the high level of polymerization of silicate chains. In HS pastes, the presence of portlandite (due to PC in the material) and gypsum (due to the activator) explains their intermediate performance, in between CEM IV and AAS. The authors have been able to carry out the present research thanks to financial support from the Ministerio de Ciencia, Innovación y Universidades of Spain (RTI2018-096428-B-I00 and PID2020-116738RJ-I00 projects) and Madrid Government (Comunidad de Madrid) under the Multiannual Agreement UC3M in the line of "Fostering Young Doctors Research" (HORATSO-CS-UC3M) in the context of the V PRICIT (Regional Programme of Research and Technological Innovation).

This study is part of the research line that sees it necessary to develop materials that are alternatives for Portland cement (PC), using industrial by-products such as blast furnace slag and fly ash. This line arises because of the serious environmental consequences suffered by our planet throughout many decades, which have led the cement industry to reduce the amount of CO2 emitted in the production of PC, since it is a highly polluting process. The chemical and physical properties of the materials were studied. In this way, the study of the thermal properties is interesting to test the feasibility of the mortars to use them as solid media to storage thermal energy, since most of the research focus on the thermal properties of concrete is oriented toward fire resistance. Storing solar thermal energy improves the operation of solar power thermal plants. It is being studied that the use of concrete (composed of PC) contributes efficiently to concentrated solar power (CSP) technology. To avoid the use of PC due to environmental concerns, alkaline-activated mortars are manufactured with blast furnace slag using alkaline solutions such as sodium hydroxide (NaOH) and commercial sodium silicate (SiO2/Na2O = 0.8), as well as hybrid mortars using 80% fly ash or blast furnace slag and 20% PC. After experimental analysis and a simulation to measure the conduction within the mortars through a commercial Computational Fluid Dynamic software (CFD, ANSYS Fluent), it can be concluded that the mechanical and thermal properties of most of the alternative mortars manufactured in this study are better than the ones obtained in the PC. Most notably, the slag alkaline-activated mortar increases those properties significantly. Este estudio se enmarca en la línea de investigación que ve necesario el desarrollo de materiales alternativos al cemento Portland (PC), utilizando subproductos industriales como las escorias de alto horno y las cenizas volantes. Esta línea surge debido a las graves consecuencias medioambientales que ha sufrido nuestro planeta a lo largo de muchas décadas, que han llevado a la industria cementera a reducir la cantidad de CO2 emitida en la producción de PC, ya que es un proceso altamente contaminante. Se estudiaron las propiedades químicas y físicas de los materiales. Así, el estudio de las propiedades térmicas es interesante para comprobar la viabilidad de los morteros para utilizarlos como medios sólidos de almacenamiento de energía térmica, ya que la mayor parte de las investigaciones centradas en las propiedades térmicas del hormigón están orientadas a la resistencia al fuego. El almacenamiento de energía térmica solar mejora el funcionamiento de las centrales termosolares. Se está estudiando que el uso del hormigón (compuesto de PC) contribuye eficazmente a la tecnología de energía solar concentrada (CSP). Para evitar el uso del PC por motivos medioambientales, se fabrican morteros activados con escoria de alto horno utilizando soluciones alcalinas como el hidróxido de sodio (NaOH) y el silicato de sodio comercial (SiO2/Na2O = 0,8), así como morteros híbridos que utilizan un 80% de cenizas volantes o escoria de alto horno y un 20% de PC. Tras el análisis experimental y una simulación para medir la conducción dentro de los morteros mediante un software comercial de dinámica de fluidos computacional (CFD, ANSYS Fluent), se puede concluir que las propiedades mecánicas y térmicas de la mayoría de los morteros alternativos fabricados en este estudio son mejores que las obtenidas en el PC. En particular, el mortero activado alcalinamente con escoria aumenta significativamente esas propiedades. This work has been supported by the Madrid Government (Comunidad de Madrid) under the Multiannual Agreement with UC3M in the line of "Fostering Young Doctors Research" (HORATSO-CM-UC3M) in the context of the V PRICIT (Regional Programme of Research and Technological Innovation).

Membrane-bound immunoglobulin and T-cell receptors serve as the antigen receptors for B cells and T cells respectively. This chapter summarizes the molecular genetics of immunoglobulins and T-cell receptors, the recombination and somatic mutation processes used to engender diversity, the adapters that enable these surface molecules to signal into the interior of the cell, and the coreceptors that are used to modify the signal.

Introduction: Despite the recommendations of the current Clinical Practice Guidelines, the chest x-ray continues to be a widely used diagnostic test in the assessment of infants with acute bronchiolitis (AB). However, there have not been many studies that have assessed its reproducibility in these patients. In the present study, an evaluation is made on the radiographs, describing their quality, their radiological findings, and provides new evidence on the agreement between observers. Method: Out of a total of 281 infants admitted due to acute bronchiolitis, 140 chest x-rays were performed. Twelve doctors from different specialities evaluated the presence or absence of 10 radiological signs previously agreed by consensus. The level of agreement between 2 observers, and in groups of 3 or more, were analysed using the Cohen and Fleiss kappa index, respectively. Results: Only 8.5% of the radiographs showed evidence of a complicated AB. The between-observer agreement in groups of 3 or more was medium, and with little variability (kappa: 0.20−0.40). However, between 2 observers, specialists in radiology, the variability was wider, (kappa: −0.20 to 0.60). This level of agreement was associated with factors including, the sign to evaluate, the medical specialty, and level of professional experience. Conclusion: The low levels of agreement between observers and the wide variability, makes the chest x-ray an unreliable diagnostic tool, and is not recommended for the assessment of infants with AB. Resumen: Introducción: A pesar de las recomendaciones de las actuales Guías de Práctica Clínica, la radiografía de tórax sigue siendo una prueba diagnóstica ampliamente utilizada en la evaluación de lactantes con bronquiolitis aguda. No obstante, su reproductibilidad en estos pacientes no ha sido muy estudiada. En la presente investigación, se evalúan radiografías describiéndose su calidad técnica, hallazgos radiológicos en las mismas y se aportan nuevas evidencias sobre la concordancia entre observadores. Método: Sobre un total de 281 lactantes ingresados por bronquiolitis aguda, 140 radiografías de tórax fueron realizadas. 12 médicos de diferentes especialidades evaluaron la presencia o ausencia de 10 signos radiográficos previamente consensuados. El nivel de concordancia entre 2 observadores y en grupos de 3 o más, fue estudiado mediante el índice kappa de Cohen y de Fleiss respectivamente. Resultados: Únicamente en el 8,5% de las radiografías se evidenciaron signos de BA complicada. La concordancia entre observadores en grupos de 3 o más fue mediana y con escasa variabilidad (kappa: 0,20−0,40), sin embargo, entre 2 observadores, especialista con radiólogo de referencia, la variabilidad fue más amplia, (kappa: −0,20 to 0,60). Este nivel de concordancia se relacionaba con factores tales como el signo a evaluar, la especialidad médica y el grado de experiencia profesional, entre otros. Conclusión: Los bajos niveles de concordancia entre observadores y su amplia variabilidad, convierten a la radiografía de tórax en una herramienta diagnóstica poco fiable y no recomendable para la evaluación de lactantes con BA.

Background Intrahepatic lithiasis (IHL) is a rare disease in the western world. Complications associated with IHL include acute cholangitis, liver atrophy, secondary biliary cirrhosis, and risk for intrahepatic cholangiocarcinoma. Liver resection is considered the treatment of choice for IHL. The objective of this study was to analyze patients who underwent liver resection for non-Asian hepatolithiasis. Methods 127 patients with symptomatic non-Asian hepatolithiasis underwent resection in six institutions. Demographic data, clinical presentation, diagnosis, classification according to stone location, presence of atrophy, bile duct stricture, biliary cirrhosis, incidence of cholangiocarcinoma, treatment and postoperative course were evaluated. Results 52 patients (40.9%) were male and the mean age was 46.1 years. Sixty-six patients (51.9%) presented with history of cholangitis. Stones were located in the left lobe in 63 (49.6%), and right lobe in 28 patients (22.0%). Atrophy was observed in 31 patients (24.4%) and biliary stenosis in 18 patients (14.1%). The most common procedure performed was left lateral sectionectomy in 63 (49.6%) patients, followed by left hepatectomy in 36 (28.3%), right hepatectomy in 19 (15.0%), and associated hepaticojejunostomy in 28 (22.0%). Forty-two patients (33.0%) presented postoperative complications and the most common were biliary fistula (13.3%) and surgical site infection (7.0%). Postoperative mortality was 0.7%. Intrahepatic cholangiocarcinoma was observed in 2 patients (1.5%). Recurrence was identified in 10 patients (7.8%), mostly with bilateral stones and/or hepaticojejunostomy. Conclusion Liver resection is the standard treatment for symptomatic unilateral or complicated IHL with good operative results. Risk of cholangiocarcinoma was low in non-Asian patients.

SummaryViruses often encode proteins that mimic host proteins in order to facilitate infection. Little work has been done to understand the potential mimicry of the SARS-CoV-2, SARS-CoV, and MERS-CoV spike proteins, particularly the receptor-binding motifs, which could be important in determining tropism of the virus. Here, we use structural bioinformatics software to characterize potential mimicry of the three coronavirus spike protein receptor-binding motifs. We utilize sequence-independent alignment tools to compare structurally known or predicted three-dimensional protein models with the receptor-binding motifs and verify potential mimicry with protein docking simulations. Both human and non-human proteins were found to be similar to all three receptor-binding motifs. Similarity to human proteins may reveal which pathways the spike protein is co-opting, while analogous non-human proteins may indicate shared host interaction partners and overlapping antibody cross-reactivity. These findings can help guide experimental efforts to further understand potential interactions between human and coronavirus proteins.HighlightsPotential coronavirus spike protein mimicry revealed by structural comparisonHuman and non-human protein potential interactions with virus identifiedPredicted structural mimicry corroborated by protein-protein dockingEpitope-based alignments may help guide vaccine effortsGraphical abstract

Highlights • Uniforms were integrated over time, but once integrated were not removed when hotter environmental conditions occurred. • Players in the age-restricted league were taller, heavier, and had a higher BMI than players in the weight-restricted league, resulting in significant anthropometric differences. • Work time was significantly greater for games, as were rest times. However, work-to-rest ratios were significantly higher for practices. • Of the practices and games observed 9% were held in black flag risk conditions and 68% were held in red flag conditions. • One league's average WBGT during games was significantly higher than the other because of the time of day they were held (9:00 a.m. to 2:00 p.m.). • More than 50% of players reached a gastrointestinal temperature of 39°C or higher at least once during the observation, but no players reached a TG1 indicative of exertional heat stroke., Objective To determine which intrinsic and extrinsic exertional heat illness (EHI) risk factors exist in youth American football players and observe perceptual and physiological responses of players during events (games and practices). Methods Cross-sectional cohort study observing 63 youth football players, varying in position. Independent variables were league (weight-restricted (WR, n = 27) and age-restricted (AR, n = 36)) and event type. Dependent variables were anthropometrics, work-to-rest ratio, and wet bulb globe temperature. Descriptive variables included preparticipation examination and uniform configuration. A subset of 16 players participated in physiological variables (heart rate and gastrointestinal temperature). Data collection occurred on 7 AR and 8 WR nonconsecutive practices and the first 3 games of the season. Results Mean values for anthropometric variables were higher (p < 0.05) in the AR league than the WR league. Work time (χ2 (1,111) = 4.232; p = 0.039) and rest time (χ2 (1,111) = 43.41; p < 0.001) were significantly greater for games, but ratios were significantly higher for practices (χ2 (1,111) = 40.62; p < 0.001). The majority of events (77%) observed were in black and red flag wet bulb globe temperature risk categories. A total of 57% of the players had a preparticipation examination, and up to 82% of events observed were in full uniforms. Individual gastrointestinal temperature and heart rate responses ranged widely and no players reached critical thresholds. Conclusion Extrinsic (disproportionate work ratios, environmental conditions) and intrinsic (higher body mass index) EHI risk factors exist in youth football. Certain risk factors may be influenced by event and league type. National youth football organizations need to create thorough guidelines that address EHI risk factors for local leagues to adopt., Graphical Abstract Image, graphical abstract

The kaolin mining waste (KW) is a residue generated during the purification process of extracting high purity kaolin used in different industries. KW is mainly constituted by kaolinite-rich clay and other secondary minerals such as anatase and quartz. With the appropriated and controlled process, calcined kaolin mining waste (CKW). It can be thermally activated by calcination to obtain a highly reactive metakaolinite rich material, which exhibits interesting pozzolanic properties. According to its chemical composition and high reactivity, this material is used as an aluminosilicate precursor in the production of geopolymers. One of the negative effects may be the formation of efflorescence. This paper evaluated geopolymer produced with CKW at different activation conditions (alkali concentration and sodium silicate content). The leaching of alkalis was studied through the development of efflorescence on the surface of hardened samples exposed to efflorescence formation conditions (contact with air and water). The results indicated that a larger activator provided a higher compressive strength and reduced the capillary absorption and the efflorescence formation. The data showed that the efflorescence formation can be appropriately controlled by adjusting the mix design parameters, especially the sodium silicate content.

Life Cycle Assessment (LCA) is a tool that allows assessing the potential environmental impacts of processes, products, or systems along its entire life cycle. LCA is a standardized methodology that follows the ISO 14040/14044 standards, which constitutes a power decision-support tool for engineers, scientists, governments and industry in the quest for sustainability. This chapter provides a comprehensive overview of the theory and practice of LCA. Throughout this chapter, the importance of LCA is motivated and explained by assessing an illustrative example that compares the environmental performance of two alternative water bottles, that is, plastic bottle versus aluminum bottle. The first part presents an introduction to the phases of LCA, which involves (1) defining the goal and scope of the study, (2) performing the inventory of all the material and energy inputs and outputs related to the studied system, (3) translating the inventories into potential environmental impacts and (4) drawing conclusions and recommendations. Then, LCA applications in different areas are briefly discussed, including the sustainable design of processes/products, strategic planning and public policy-making, among others. Finally, in the last section, this chapter includes a case study of the application of LCA in practice to assess the carbon footprint of biodiesel.

Hybrid cements (HC) are a possible replacement of Portland cement, as their activation process only requires a small amount of sulphates, and is carried out with water at room temperature. The present work aims to study the wear behaviour of HC manufactured from two different wastes: blast furnace slag (HS) and fly ash (HFA). Their wear behaviour was compared to Portland cements (CEM I and CEM IV). Reciprocating wear tests and rolling wear Böhme tests were carried out for pastes and mortars, respectively. Wear tracks in the pastes were analysed through opto-digital microscopy and electron microscopy (SEM). In the mortars, the mechanical resistance was measured to understand different behaviours. The results obtained reveal that HC pastes and mortars present lower wear losses than CEM IV and similar to CEM I. This work has been supported by the Madrid Government (Comunidad de Madrid) under the Multiannual Agreement with UC3M in the line of "Fostering Young Doctors Research" (HORATSO-CM-UC3M) in the context of the V PRICIT (Regional Programme of Research and Technological Innovation), and by the Ministerio de Ciencia, Innovación y Universidades of Spain through project RTI2018-096428-B-I00.

Latino people in the US are experiencing higher excess deaths during the COVID-19 pandemic than any other racial/ethnic group, but it is unclear which sociodemographic subgroups within this diverse population are most affected. Such information is necessary to target policies that prevent further excess mortality and reduce inequities. Using death certificate data for January 1, 2016 through February 29, 2020 and time-series models, we estimated the expected weekly deaths among Latino people in California from March 1 through October 3, 2020. We quantified excess mortality as observed minus expected deaths and risk ratios (RR) as the ratio of observed to expected deaths. We considered subgroups categorized by age, sex, nativity, country of birth, educational attainment, occupation, and combinations of these factors. Our results indicate that during the first seven months of the pandemic, Latino deaths in California exceeded expected deaths by 10,316, a 31% increase. Excess death rates were greatest for individuals born in Mexico (RR 1.44; 95% PI, 1.41, 1.48) or a Central American country (RR 1.49; 95% PI, 1.37, 1.64), with less than a high school degree (RR 1.41; 95% PI, 1.35, 1.46), or in food-and-agriculture (RR 1.60; 95% PI, 1.48, 1.74) or manufacturing occupations (RR 1.59; 95% PI, 1.50, 1.69). Immigrant disadvantages in excess death were magnified among working-age Latinos in essential occupations. In sum, the COVID-19 pandemic has disproportionately impacted mortality among Latino immigrants, especially those in unprotected essential jobs. Interventions to reduce these inequities should include targeted vaccination, workplace safety enforcement, and expanded access to medical care and economic support., Highlights • During the first seven months of the pandemic, Latino deaths in California exceeded expected deaths by 10316, a 31% increase. • Relative increases in mortality were greatest for Latinos born in Mexico or Central America, Latinos with less than a high school degree, and Latinos in food-and-agriculture or manufacturing occupations. • Immigrants in essential occupations had the highest relative increase in death during the pandemic among working-age Latinos. • Workplace exposure may be key contributor to the disproportionately high COVID-19 mortality experienced by Latinos in CA.

[Resumen] Antecedentes y objetivo. El síndrome de hombro doloroso postictus (HDPI) es una de las complicaciones más comunes tras un accidente cerebrovascular. Un estudio español estableció su incidencia en torno el 53% en el año 2001; no hay estudios más recientes. El objetivo de este estudio fue obtener información epidemiológica actualizada del HDPI en España y, secundariamente, obtener información de interés sobre su atención clínica. Pacientes y métodos. Estudio observacional prospectivo sobre 1.000 pacientes. Los pacientes fueron seleccionados de todos los servicios responsables de la asistencia clínica de pacientes postictus de un área sanitaria completa y seguidos durante un año. Fueron analizadas variables sociodemográficas, características del HDPI y factores relacionados con la asistencia médica. Se realizó un análisis descriptivo de las variables, empleando la función de Kaplan Meier para analizar la incidencia acumulada del HDPI. Resultados. Constituyeron la muestra final 576 individuos, de los cuales 119 (21%) presentaron HDPI. El 58% de ellos fue derivado a rehabilitación con un periodo de espera medio de 31 días. El diagnóstico del HDPI se dio en la mayoría de los casos tras el alta hospitalaria. Los servicios de rehabilitación detectaron el 41% de los casos, mientras que los servicios de Atención Primaria detectaron el 26%. Conclusiones. El HDPI es una complicación frecuente. La implementación de una pronta atención rehabilitadora y la reducción del periodo de ingreso hospitalario, en aquellos casos que resulte posible, podrían facilitar su asistencia médica. Una mayor participación de los servicios de rehabilitación y ambulatorios en los protocolos de valoración podría igualmente mejorar el diagnóstico y seguimiento de estos pacientes. [Abstract] Background and objective. Post-stroke shoulder pain (PSSP) syndrome is a common complication after stroke. The most recent reference (2001) established PSSP incidence in Spain is around 53%. The objective of the current study was to obtain PSSP epidemiological data in Spain at present, obtaining information of interest about its clinical care secondarily. Patients and methods. A prospective observational study was developed on 1,000 patients, which were selected from all levels responsible of stroke patients care of one health area and followed-up during one year. Sociodemographic data, PSSP characteristics and medical care parameters were collected. Descriptive analysis was performed, using modified Kaplan-Meier function to show PSSP cumulative incidence. Results. The final sample consisted of 576 individuals, of which 119 (21%) were diagnosed with PSSP; 58% of the PSSP group was transferred to rehabilitation departments, delaying for a mean of 31 days. Most of patients were diagnosed with PSSP after hospital discharge: rehabilitation departments detected 41% of PSSP cases, while the primary care department detected 26%. Conclusions. PSSP is a frequent complication. Implementing a prompt rehabilitation care and a reduced hospital stay, where possible, could improve the PSSP medical care. Increasing the participation of rehabilitation and primary care departments in the PSSP assessment could substantially improve the diagnosis and follow-up of these patients.

The present study focuses on exploring the effects of reactivity and degree of dispersion of BaCO additions in the manufacture of sulfate-resistant OPC cements. A new electrochemical deposition method is attempted to effectively disperse BaCO particles (studying two different materials with particle size: D = 11.45 and 2.37 μm) on cement to enhance their reactivity and favour sulfate immobilisation in the form of BaSO. The barium carbonate additions, particularly the finest, activate cement hydration to a greater extent. Electrodeposition is also observed to improve early age reactivity (2 d–7 d) in fine BaCO. Cement paste bearing 15 wt % BaCO is more resistant to sulfate attack by a 5% (w/v) solution of NaSO (180 d at 23 °C) than a commercial sulfate-resistant cement, although secondary ettringite and gypsum precipitated in all cases., This study was funded by the Spanish Ministry of the Economy and Competitiveness and the European Regional Development Fund, BIA2015-73237-JIN project (MINECO/ERDF; EU) and MAT2017- 86450-C4-1-R. The authors wish to thank Grupos Cementos Portland Valderrivas and in particular Germ´an García P´erez for the supply of the OPCs used.

We prove Cauchy's formula for repeated integration on time scales. The obtained relation gives rise to new notions of fractional integration and differentiation on arbitrary nonempty closed sets., Comment: This is a preprint of a paper whose final and definite form is published by 'Applied Mathematics Letters' (ISSN: 0893-9659), available at [https://doi.org/10.1016/j.aml.2021.107407]. Please cite this article as: D.F.M. Torres, Cauchy's formula on nonempty closed sets and a new notion of Riemann-Liouville fractional integral on time scales, Appl. Math. Lett. 121 (2021), Art. 107407, 6 pp

We investigate a mathematical model in crop pest management, considering plant biomass, pest, and the effect of farming awareness. The pest population is divided into two compartments: susceptible pest and infected pest. We assume that the growth rate of self-aware people is proportional to the density of healthy pests present in the crop field. Impacts of awareness is modeled via a saturated term. It is further assumed that self-aware people will adopt biological control methods, namely integrated pest management. Susceptible pests are detrimental to crops and, moreover, there may be some time delay in measuring the healthy pests in the crop field. A time delay may also take place while becoming aware of the control strategies or taking necessary steps to control the pest attack. In agreement, we develop our model incorporating two time delays into the system. The existence and the stability criteria of the equilibria are obtained in terms of the basic reproduction number and time delays. Stability switches occur through Hopf-bifurcation when time delays cross critical values. Optimal control theory has been applied for the cost-effectiveness of the delayed system. Numerical simulations illustrate the obtained analytical results., This is a preprint of a paper whose final and definite form is published by 'Chaos Solitons Fractals' (ISSN: 0960-0779). Paper Submitted 08/Sept/2020; Revised 25/Feb/2021; Accepted 10/March/2021

Background Chronic pancreatitis is a progressive inflammation of the pancreas associated to fibrosis, pancreatic atrophy, calcifications, and chronic pain. Intractable pain is the main indication for surgical treatment. Surgical procedures are based in ductal decompression, ductal drainage, and resection. Aim Analyze the surgical management of patients with symptomatic calcified chronic pancreatitis. Methods From March 2009 and September 2019, 12 patients underwent surgical treatment due to chronic calcified pancreatitis. There were eleven male (91.7%) and one female (8.3%) and the mean age was 58.2 years (range 48–70 years). Regular alcohol ingestion was observed in all patients (100%). The main indication for surgery was pain control in ten patients (83.3%). Results The procedures included Partington-Rochelle (6 patients, 50.0%), Frey procedure (3 patients, 25.0 %), pancreatoduodenectomy (2 patients, 16.6%) and total pancreatectomy (1 patient, 8.3%). Four patients (33.3%) had postoperative complications. No Clavien-Dindo ≥ 3b complications and no 90-days mortality were recorded in this series. Postoperative exocrine dysfunction was observed in 4 patients (33.3%), and all of them received pancreatic enzyme supplement. Conclusions Surgical treatment is a safe and feasible choice with acceptable morbidity and no mortality for symptomatic patients with calcified chronic pancreatitis.

The incorporation of crushed glass as a substitute for natural aggregates in mortar and concrete represents a positive impact on the manufacturing processes. The use of glass residues can lead to the improvement of certain properties of sustainable construction products. In these cases, it is important to analyse in detail the behaviour of the material to verify possible applications at an industrial level and contribute to the development of new construction products and solutions. This work studies the behaviour of mortars with recycled glass as a partial replacement of aggregate against common accelerated decay tests, such as salt crystallization, freezing and thermal shock. The influence on the basic physical and mechanical properties has been evaluated by statistical analysis of the results, observing a particularly significant improvement in the resistance of mortars with recycled glass against the expansive action of salt crystallization (>20%). The influence of alteration processes on the internal structure has been analysed by ultrasound transmission tests and its correlation with Young's modulus. The values obtained are in the range of similar materials, having the samples subjected to freezing test a major degree of deterioration. The internal structures have been studied by scanning electron microscopy, observing in samples subjected to salt crystallization tests a greater homogeneity and a lower degree of microcracking in the aggregate/paste interfaces of the glass grains. © 2021 The Author(s)

The wear resistance of organic coatings has an important role in order to extend their in-service life. Epoxy powder coatings were mixed with nanosilica through ball milling to study their effect on the wear performance after ultraviolet (UV) exposure. Two types of SiO2 nanoparticles were added: hydrophilic (HL) and hydrophobic (HB) at different percentages (0.25–1% by wt.). Modified powders were applied by electrostatic spraying gun on carbon steel sheets. After curing, coatings were exposed to a xenon lamp for 500 h. The surface of coatings was analyzed by scanning electron microscope (SEM). Reciprocating sliding wear tests were performed at room temperature and dry conditions, under 5 N load and 10 Hz frequency. The countermaterial was a 6 mm-stainless steel ball. Wear tracks were analyzed by an optoelectronic microscope and SEM. In order to analyze possible chemical changes, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was performed. Finally, universal hardness was evaluated to study mechanical properties. Results reveal that small amounts of both types of nanosilica, make the epoxy-matrix coatings chemically degrade less than non-reinforced ones under irradiation, increasing their mechanical behavior and thus wear resistance. The 0.75-1HL and the 0.75HB coatings exhibit the best wear performance after UV exposure. The authors acknowledge Universidad Pontificia Comillas and Cubson International Consulting for their support with the ATR-FTIR tests and with the organic coating process respectively. Funding by Interreg SUDOE, through the KrEaTive Habitat project [grant number SOE1/P1/E0307], is also acknowledged.

During last two decades, several strategies have been developed to improve the semiconductor properties in order to enhance their activity for different applications in green photocatalysis such as energy conversion, degradation, antibacterial, and so on. In this chapter it is presented a brief summary of the most common strategies which are related to: 1) coupling of semiconductors, 2) incorporation of cocatalyst, 3) use of sacrificial agents, 4) doping of metal and non-metal ions, and 5) control of morphology. The improvement of semiconductor materials still is an opportunity area that needs to be attended because it is necessary to understand the mechanism of the effects on the electronical, crystalline, and surface structure, which move the energy band gap to visible region, creates active sites, enhance carrier mobility, improve photogenerated charges, and increase charge separation, factors that influences the efficiency of photocatalyst.

Heterogeneous photocatalysis is an efficient technology to remove environmental pollutants in natural sources, and recently it has been proposed as an emerging strategy to produce alternative and renewable solar fuels. Nevertheless, the efficiency and stability of traditional photocatalysts are still challenging. As an alternative, the application of heterostructured photocatalysts has resulted in a good strategy to increase the efficiency and stability of materials in these reactions. This chapter, after it describes the working principle of heterostructured materials, presents a summary of the different synthesis methods to obtain them. Then, the application of several heterostructured materials to remove air pollutants (such as NOx, SO2, and VOCs) and other emerging contaminants from water, soil, and different microorganisms was discussed. Finally, recent findings to produce alternative solar fuels from CO2 reduction and water splitting reactions with heterostructured materials were also analyzed trying to explain how different configurations have served to enhance the efficiencies in the evolved products. In general, this chapter is expected to provide a useful reference for researchers in designing and exploring new applications of heterostructured photocatalytic materials for air treatment and energy generation.

We prove new estimates of the Caputo derivative of order $\alpha \in (0,1]$ for some specific functions. The estimations are shown useful to construct Lyapunov functions for systems of fractional differential equations in biology, based on those known for ordinary differential equations, and therefore useful to determine the global stability of the equilibrium points for fractional systems. To illustrate the usefulness of our theoretical results, a fractional HIV population model and a fractional cellular model are studied. More precisely, we construct suitable Lyapunov functionals to demonstrate the global stability of the free and endemic equilibriums, for both fractional models, and we also perform some numerical simulations that confirm our choices., Comment: This is a preprint of a paper whose final and definite form is published in 'Chaos, Solitons & Fractals', available at [http://dx.doi.org/10.1016/j.chaos.2020.110224]. Submitted 25-May-2020; Revised 25-July-2020; Accepted 19-August-2020

Alkali-activated materials (AAM) are a possible alternative to Portland cement. Their wear performance opens a new door in the study of their durability for their use, in airport runways, highways and fabrication of construction materials. The wear behavior of AAM, under different activation conditions, is compared to Portland cement. Besides mechanical and physical characterization, reciprocating sliding wear tests were carried out. Information about the changes of structure and composition due to wear was obtained. Wear mechanism is abrasive for all pastes. Slag pastes activated with waterglass present the lowest volume wear loss, approximately 60% less than Portland cement. This good behavior could be related to the high hardness and stiffness of the material, associated with the main reaction products. This study was funded by the Ministerio de Ciencia, Innovación y Universidades of Spain through project RTI2018-096428-B-I00. Publicado

In this article, exact traveling wave solutions of a Wick-type stochastic nonlinear Schr\"{o}dinger equation and of a Wick-type stochastic fractional Regularized Long Wave-Burgers (RLW-Burgers) equation have been obtained by using an improved computational method. Specifically, the Hermite transform is employed for transforming Wick-type stochastic nonlinear partial differential equations into deterministic nonlinear partial differential equations with integral and fraction order. Furthermore, the required set of stochastic solutions in the white noise space is obtained by using the inverse Hermite transform. Based on the derived solutions, the dynamics of the considered equations are performed with some particular values of the physical parameters. The results reveal that the proposed improved computational technique can be applied to solve various kinds of Wick-type stochastic fractional partial differential equations., Comment: This is a preprint of a paper whose final and definite form is with 'Chaos, Solitons & Fractals', ISSN 0960-0779 [https://doi.org/10.1016/j.chaos.2019.109542]. Submitted 19-Sept-2019; Revised 14-Nov-2019; Accepted for publication 18-Nov-2019. This version includes minor corrections detected while reading galley proofs

Using a fixed point theorem in a proper Banach space, we prove existence and uniqueness results of positive solutions for a fractional Riemann-Liouville nonlocal thermistor problem on arbitrary nonempty closed subsets of the real numbers., This is a preprint of a paper whose final and definite form is with 'Journal of King Saud University - Science', ISSN 1018-3647. Submitted 16-Dec-2016; revised 18-Feb-2017; accepted for publication 14-March-2017

Autoimmune diseases evolve from complex interactions between the immune system and self-antigens and involve several genetic attributes, environmental triggers and diverse cell types. Research using experimental mouse models has contributed key knowledge on the mechanisms that underlie these diseases in humans, but differences between the mouse and human immune systems can and, at times, do undermine the translational significance of these findings. The use of human immune system (HIS) mice enables the utility of mouse models with greater relevance for human diseases. As the name conveys, these mice are reconstituted with mature human immune cells transferred directly from peripheral blood or via transplantation of human hematopoietic stem cells that nucleate the generation of a complex human immune system. The function of the human immune system in HIS mice has improved over the years with the stepwise development of better models. HIS mice exhibit key benefits of the murine animal model, such as small size, robust and rapid reproduction and ease of experimental manipulation. Importantly, HIS mice also provide an applicable in vivo setting that permit the investigation of the physiological and pathological functions of the human immune system and its response to novel treatments. With the gaining popularity of HIS mice in the last decade, the potential of this model has been exploited for research in basic science, infectious diseases, cancer, and autoimmunity. In this review we focus on the use of HIS mice in autoimmune studies to stimulate further development of these valuable models., Highlights • Human immune system (HIS) mice bear components of the human immune system. • HIS mice engraft with human blood or hematopoietic stem cells, and sometimes thymus. • HIS mice are used to investigate development and function of the human immune system. • Immunological tolerance and autoimmune responses can be studied in HIS mice. • HIS models of autoimmunity vary in complexity and in ability to represent disease.

Gene editing constitutes a novel approach for precisely correcting disease-causing gene mutations. Frameshift mutations in COL7A1 causing recessive dystrophic epidermolysis bullosa are amenable to open reading frame restoration by non-homologous end joining repair-based approaches. Efficient targeted deletion of faulty COL7A1 exons in polyclonal patient keratinocytes would enable the translation of this therapeutic strategy to the clinic. In this study, using a dual single-guide RNA (sgRNA)-guided Cas9 nuclease delivered as a ribonucleoprotein complex through electroporation, we have achieved very efficient targeted deletion of COL7A1 exon 80 in recessive dystrophic epidermolysis bullosa (RDEB) patient keratinocytes carrying a highly prevalent frameshift mutation. This ex vivo non-viral approach rendered a large proportion of corrected cells producing a functional collagen VII variant. The effective targeting of the epidermal stem cell population enabled long-term regeneration of a properly adhesive skin upon grafting onto immunodeficient mice. A safety assessment by next-generation sequencing (NGS) analysis of potential off-target sites did not reveal any unintended nuclease activity. Our strategy could potentially be extended to a large number of COL7A1 mutation-bearing exons within the long collagenous domain of this gene, opening the way to precision medicine for RDEB., Highly efficient and safe approaches for precise correction of pathogenic mutations are required to realize the full potential of gene-editing protocols for clinical practice. Here we describe a single-step NHEJ-based CRISPR/Cas9 strategy of COL7A1 mutation-bearing exon deletion with unprecedented efficacy for ex vivo correction of recessive dystrophic epidermolysis bullosa.

In repair of acute or chronic wounds, timely closure of open wounds with continuous epithelial layer would be essential for reassurance of the barrier functions of healed skin. Meanwhile, regeneration of those accessory appendages like hair follicles in the healed wounds would be a vital step toward the restoration of the full physiologic functions of skin. To facilitate the process of abovementioned scenarios, coverage of wounds with skin grafts would be an appealing strategy. In the endeavor of creating tissue-engineered skin substitutes including epithelial sheet and those with hair follicles, it becomes recognizably important to formulate a cell-friendly microenvironment favoring the desired cell phenotype. Considering dimensional and morphological similarity of electrospun fibrous matrices to native extracellular matrix , it is highly beneficial to define the cell-growing environment with such fibers. This chapter not only provides the fundamentals on skin epithelial structures and hair follicles but also summarizes the up-to-date tactics in using electrospun matrices for engineering epithelial layers and hair follicle-like structures.

The re-use of different aluminosilicates, such as blast furnace slag, in the preparation of alternative binders (alkali-activated materials) to Portland cement materials is well document and evaluated by conventional techniques. The use of XRD, FTIR and TG techniques allows obtaining information about the hydration products formed under the conditions of alkaline activation. The formation of the main reaction product (C-A-S-H gel), due to its low crystallinity, is not easily stablished by XRD or FTIR, and it is also quite complex to obtain quantitative information. Confocal Raman Microscopy (CRM) technique reveals information of each of the present phases during the slag activation and in particular. Moreover, CRM provide the evolution of C-A-S-H gel confirming that the growth of the C-A-S-H gel in activate alkaline-systems is different from that an Ordinary Portland Cement system. C-A-S-H gel grows randomly in the regions rich in calcium and silicon. The use of CRM opens a new possibility for the in situ study of complex systems such as the activation of alkali-activated or geopolymers in the search for alternative materials to Portland cement. This work was supported by the Spanish Ministry of Economy and Competitiveness through the Project MAT-2017-86450-C4-1-R and Spanish National Research Council Project NANOMIND 201560E068. Dr. M. Torres-Carrasco is also indebted to MINECO for a postdoctoral fellowship "Juan de la Cierva-Formación" (ref: FJCI-2016-28488). In addition, O. Mikhailova enjoyed a pre-doctoral fellowship with specific junior project FAST-J-18-5568 from the Brno University of Technology (Czech Republic) for internship in Spain.

Four years׳ behavioral data of thin-film single junction amorphous silicon (a-Si) photovoltaic (PV) modules installed in a relatively dry and sunny inland site with a Continental-Mediterranean climate (in the city of Jaén, Spain) are presented in this article. The shared data contributes to clarify how the Light Induced Degradation (LID) impacts the output power generated by the PV array, especially in the first days of exposure under outdoor conditions. Furthermore, a valuable methodology is provided in this data article permitting the assessment of the degradation rate and the stabilization period of the PV modules.Further discussions and interpretations concerning the data shared in this article can be found in the research paper “Characterization of degradation and evaluation of model parameters of amorphous silicon photovoltaic modules under outdoor long term exposure” (Kichou et al., 2016) [1]. Keywords: Light-induced degradation (LID), a-Si PV modules, Stabilization period

This paper presents three direct methods based on Gr\"{u}nwald-Letnikov, trapezoidal and Simpson fractional integral formulas to solve fractional optimal control problems (FOCPs). At first, the fractional integral form of FOCP is considered, then the fractional integral is approximated by Gr\"{u}nwald-Letnikov, trapezoidal and Simpson formulas in a matrix approach. Thereafter, the performance index is approximated either by trapezoidal or Simpson quadrature. As a result, FOCP are reduced to nonlinear programming problems, which can be solved by many well-developed algorithms. To improve the efficiency of the presented method, the gradient of the objective function and the Jacobian of constraints are prepared in closed forms. It is pointed out that the implementation of the methods is simple and, due to the fact that there is no need to derive necessary conditions, the methods can be simply and quickly used to solve a wide class of FOCPs. The efficiency and reliability of the presented methods are assessed by ample numerical tests involving a free final time with path constraint FOCP, a bang-bang FOCP and an optimal control of a fractional-order HIV-immune system., Comment: This is a preprint of a paper whose final and definite form is with 'Commun. Nonlinear Sci. Numer. Simul.', ISSN 1007-5704, available at [http://dx.doi.org/10.1016/j.cnsns.2018.05.011]. Submitted 25-March-2018; Accepted for publication 16-May-2018

We propose a stochastic SICA epidemic model for HIV transmission, described by stochastic ordinary differential equations, and discuss its perturbation by environmental white noise. Existence and uniqueness of the global positive solution to the stochastic HIV system is proven, and conditions under which extinction and persistence in mean hold, are given. The theoretical results are illustrated via numerical simulations., Comment: This is a preprint of a paper whose final and definite form is with 'Applied Mathematics Letters', ISSN 0893-9659. Submitted 22/Jan/2018; Revised 03/May/2018; Accepted for publication 03/May/2018

Chapitre 18; International audience; Olive trees are one of the most representative horticultural crops of the Mediterranean environments. Its plethora of physiological mechanisms of response to water stress have made of this species one of the most studied ones in this respect in the literature in the last two decades. Also, despite being exalted as one of the stereotypes of dry-farming crop, olive trees' generous response to irrigation has demanded a large amount of work on how to manage them in the very water scarce environment where they are grown. In this chapter we will not do another review of the physiological mechanisms of response of olive trees to water stress. Nonetheless, we intend to integrate all of them, with the help of mechanistic models, to unravel which are the consequences, trade-offs, and limits of the implementation of these mechanisms for the plant in response to drought events. Once this is achieved, we will answer questions such as: Why can olive trees afford to drop their water potential by osmotic adjustment while other crops like grapevine cannot? What are the causes behind the change in the relationship between stomatal conductance and leaf water potential during acclimation to water stress? What is the role of abscisic acid (ABA) in the regulation of stomatal conductance in response to water stress? And, in light of these findings, what is the most appropriate physiological variable to assess the level of water stress in olive trees and what should the optimal plant-based sensor measure to help us manage deficit irrigation?