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Metal Oxide (MOX) gas sensors rely on chemical reactions that occur efficiently at high temperatures, resulting in too-demanding power requirements for certain applications. Operating the sensor under a Pulsed-Temperature Operation (PTO), by which the sensor heater is switched ON and OFF periodically, is a common practice to reduce the power consumption. However, the sensor performance is degraded as the OFF periods become larger. Other research works studied, generally, PTO schemes applying waveforms to the heater with time periods of seconds and duty cycles above 20%. Here, instead, we explore the behaviour of PTO sensors working under aggressive schemes, reaching power savings of 99% and beyond with respect to continuous heater stimulation. Using sensor sensitivity and the limit of detection, we evaluated four Ultra Low Power (ULP) sensors under different PTO schemes exposed to ammonia, ethylene, and acetaldehyde. Results show that it is possible to operate the sensors with total power consumption in the range of microwatts. Despite the aggressive power reduction, sensor sensitivity suffers only a moderate decline and the limit of detection may degrade up to a factor five. This is, however, gas-dependent and should be explored on a case-by-case basis since, for example, the same degradation has not been observed for ammonia. Finally, the run-in time, i.e., the time required to get a stable response immediately after switching on the sensor, increases when reducing the power consumption, from 10 minutes to values in the range of 10-20 hours for power consumptions smaller than 200 microwatts.

Street lighting has a big impact on the energy consumption of Spanish municipalities. To decrease this consumption, the Spanish government has developed two different regulations to improve energy savings and efficiency, and consequently, reduce greenhouse-effect gas emissions. However, after these efforts, they have not obtained the expected results. To improve the effectiveness of these regulations and therefore to optimize energy consumption, a study has been done to analyze the different devices which influence energy consumption with the intention of better understanding their behavior and performance. The devices analyzed were lamps, ballasts, street lamp globes, control systems and dimmable lighting systems. To improve their performance, they have been analyzed from three points of view: changes in technology, use patterns and standards. Thanks to this study, some aspects have been found that could be taken into account if we really wanted to use energy efficiently.

Energy consumption rose about 28% over the 2001 to 2011 period in the Spanish residential sector. In this environment, domestic hot water (DHW) represents the second highest energy demand. There are several methodologies to estimate DHW consumption, but each methodology uses different inputs and some of them are based on obsolete data. DHW energy consumption estimation is a key tool to plan modifications that could enhance this consumption and we decided to update the methodologies. We studied DHW consumption with data from 10 apartments in the same building during 18 months. As a result of the study, we updated one chosen methodology, adapting it to the current situation. One of the challenges to improve efficiency of DHW use is that most of people are not aware of how it is consumed in their homes. To help this information to reach consumers, we developed a website to allow users to estimate the final electrical energy needed for DHW. The site uses three estimation methodologies and chooses the best fit based on information given by the users. Finally, the application provides users with recommendations and tips to reduce their DHW consumption while still maintaining the desired comfort level.

Introducción: La anemia posoperatoria es una complicación importante en pacientes sometidos a una artroplastia total de cadera (ATC). El objetivo principal de este estudio fue evaluar la prevalencia de anemia posoperatoria en pacientes sometidos a una ATC programada y determinar si está relacionada con el tratamiento tromboprofiláctico administrado. Materiales y Métodos: Ensayo prospectivo aleatorizado. Se incluyó a 358 pacientes sometidos a una ATC programada entre febrero de 2019 y enero de 2022, que fueron divididos en 3 grupos para recibir: rivaroxabán 10 mg, enoxaparina sódica 40 mg o aspirina 100 mg como estrategia de tromboprofilaxis diaria. Resultados: No hubo casos de enfermedad tromboembólica confirmada ni de hemorragia grave. Los niveles de hemoglobina y hematocrito fueron similares en todos los grupos de tratamiento, sin diferencias estadísticamente significativas. No se hallaron diferencias en la incidencia de complicaciones. La suplementación con hierro fue significativamente mayor en el grupo de enoxaparina (p = 0,041). La incidencia de anemia en el modelo de regresión ordinal se asoció con la edad (OR 1,02; IC95% 1,00-1,05; p 0,04), el sexo masculino (OR 0,33; IC95% 0,19-0,56; p

The global demand for single-use personal protective equipment (PPE) is rapidly increasing. Most PPE items are composed of plastics, which often end up in landfills or oceans, causing significant environmental harm. Additionally, the disposal of PPE is costly, as it is classified as biological waste. In this study, sanitary PPE components were sterilized using supercritical CO2 at 40°C and 10 MPa, with the addition of small amounts of additives (

Abstract Same-sex sexual behaviour has attracted the attention of many scientists working in disparate areas, from sociology and psychology to behavioural and evolutionary biology. Since it does not contribute directly to reproduction, same-sex sexual behaviour is considered an evolutionary conundrum. Here, using phylogenetic analyses, we explore the evolution of same-sex sexual behaviour in mammals. According to currently available data, this behaviour is not randomly distributed across mammal lineages, but tends to be particularly prevalent in some clades, especially primates. Ancestral reconstruction suggests that same-sex sexual behaviour may have evolved multiple times, with its appearance being a recent phenomenon in most mammalian lineages. Our phylogenetically informed analyses testing for associations between same-sex sexual behaviour and other species characteristics suggest that it may play an adaptive role in maintaining social relationships and mitigating conflict.

Abstract The internal transcribed spacers (ITS) exhibit concerted evolution by the fast homogenization of these sequences at the intragenomic level. However, the rate and extension of this process are unclear and might be conditioned by the number and divergence of the different ITS copies. In some cases, such as hybrid species and polyploids, ITS sequence homogenization appears incomplete, resulting in multiple haplotypes within the same organism. Here, we studied the dynamics of concerted evolution in 85 individuals of seven plant species of the genus Erysimum (Brassicaceae) with multiple ploidy levels. We estimated the rate of concerted evolution and the degree of sequence homogenization separately for ITS1 and ITS2 and whether these varied with ploidy. Our results showed incomplete sequence homogenization, especially for polyploid samples, indicating a lack of concerted evolution in these taxa. Homogenization was usually higher in ITS2 than in ITS1, suggesting that concerted evolution operates more efficiently on the former. Furthermore, the hybrid origin of several species appears to contribute to the maintenance of high haplotype diversity, regardless of the level of ploidy. These findings indicate that sequence homogenization of ITS is a dynamic and complex process that might result in varying intra- and inter-genomic diversity levels.

Polypropylene-based thermoplastic elastomers continue to be materials of enormous industrial interest because of their high mechanical performance and durability. These materials are especially important, for instance, in the automotive industry, where these polyolefins accounts for up to 32% of the total plastic used in a car. In the search for new grades, poly(propylene-co-ethylene-co-norbornene) terpolymers might be of interest for the production of a new class of thermoplastic elastomers, whose properties could be tailored by controlling the composition, as well as its distribution. Unfortunately, thorough characterization of these materials has not been possible so far, because of the complexity of their 13CNMR spectra. In this work, two series of poly(propylene-co-norbornene) copolymers and poly(propylene-co-ethylene-co-norbornene) terpolymers, containing low molar fractions of norbornene and ethylene-norbornene, respectively, have been synthesized and characterized in detail by NMR analysis. The comparison of 13CNMR spectra in both series and their respective changes with norbornene ratio in the feed enables a complete assignment of signals, which reveals that the terpolymers are featured by a well-defined microstructure, consisting of propylene sequences bound by both PEP triads and well-defined norbornene-ethylene sequences. Such a particular distribution results from an associated insertion of the ethylene and the norbornene that, in addition, accounts for the higher contents of both comonomers, when compared with their respective copolymers, obtained under the same reaction conditions.

Resumen: Introducción: La endocarditis infecciosa (EI) es una patología que conlleva una elevada morbimortalidad y representa un problema creciente de salud pública. El tratamiento quirúrgico es necesario en más de la mitad de los casos, y su principal finalidad es eliminar totalmente el tejido infectado y reconstruir la anatomía cardiaca normal, incluyendo la reparación o la sustitución de la/s válvula/s afectada/s. Objetivo y métodos: El presente estudio se centra en describir el procedimiento más apropiado para la cirugía de reparación mitral en casos de EI, atendiendo a la literatura y a la amplia experiencia adquirida por parte del equipo quirúrgico. De igual modo, hemos recopilado a través de una búsqueda sistemática de la literatura los resultados que se han ido reportando sobre la cirugía reparadora en comparación con el reemplazo valvular mitral. Resultados: La técnica quirúrgica descrita requiere de un estudio minucioso del grado de afectación y desestructuración de los distintos segmentos valvulares. Consideramos que la resección con interposición de parche de pericardio y/o implante de neocuerdas de Goretex® es la técnica estándar que permite obtener resultados reproducibles. La revisión estructurada de las evidencias científicas disponibles verifica la seguridad de la reparación mitral para el tratamiento de la EI, aportando beneficios significativos en comparación con el reemplazo valvular. Conclusión: Los resultados quirúrgicos evaluados sugieren que la cirugía de reparación mitral debería ser considerada el procedimiento de elección para el tratamiento quirúrgico de la EI, siempre que sea técnicamente posible. Abstract: Introduction: Infective endocarditis (IE) is a pathology with a high morbidity and mortality rate and represents a growing public health problem. Surgical treatment is necessary in more than half of the cases, and its main purpose is to completely remove the infected tissue and reconstruct normal cardiac anatomy, including repair or replacement of the affected valve(s). Objectives and methods: The present study focuses on describing the most appropriate procedure for mitral repair surgery in cases of IE, based on the literature and the extensive experience gained by the surgical team. Likewise, we have compiled through a systematic search of the literature the results that have been reported on reparative surgery compared to mitral valve replacement. Results: The surgical technique described requires a thorough study of the degree of involvement and destructuring of the different valve segments. We consider resection with pericardial patch interposition and/or Goretex® neochord implantation to be the standard technique that allows reproducible results. The structured review of the available scientific evidence verifies the safety of mitral repair for the treatment of IE, providing significant benefits compared to valve replacement. Conclusion: The evaluated surgical results suggest that mitral repair surgery should be considered the procedure of choice for the surgical treatment of IE, whenever technically feasible.

In this study, we introduce an innovative policy in the field of reinforcement learning, specifically designed as an action selection mechanism, and applied herein as a selector for binarization schemes. These schemes enable continuous metaheuristics to be applied to binary problems, thereby paving new paths in combinatorial optimization. To evaluate its efficacy, we implemented this policy within our BSS framework, which integrates a variety of reinforcement learning and metaheuristic techniques. Upon resolving 45 instances of the Set Covering Problem, our results demonstrate that reinforcement learning can play a crucial role in enhancing the binarization techniques employed. This policy not only significantly outperformed traditional methods in terms of precision and efficiency, but also proved to be extensible and adaptable to other techniques and similar problems. The approach proposed in this article is capable of significantly surpassing traditional methods in precision and efficiency, which could have important implications for a wide range of real-world applications. This study underscores the philosophy behind our approach: utilizing reinforcement learning not as an end in itself, but as a powerful tool for solving binary combinatorial problems, emphasizing its practical applicability and potential to transform the way we address complex challenges across various fields.

Introducción: Las fracturas de tibia representan aproximadamente el 2% de las fracturas del adulto. El enclavado endomedular es hoy el procedimiento de elección para tratar fracturas diafisarias de tibia; sin embargo, esta técnica no está exenta de complicaciones, la desalineación en el plano coronal es una de las más frecuentes y temidas por los cirujanos. El objetivo de este estudio fue investigar la relación entre el punto de entrada del clavo y la desalineación en el plano coronal después de la cirugía. Materiales y Métodos: Se realizó un estudio retrospectivo, descriptivo, observacional, entre enero de 2015 y enero de 2019, de pacientes con fracturas diafisarias de tibia, tratadas con clavo endomedular. Se obtuvieron radiografías en el posquirúrgico inmediato y luego cada dos meses, se tuvo en cuenta la radiografía del octavo mes, en la que se observaban signos francos de consolidación ósea, para valorar la alineación tibial. Resultados: Cuando el punto de entrada del clavo fue central, hubo apenas un 0,021 de posibilidades (o 2,1%) de alguna desalineación significativa en el posquirúrgico inmediato y luego de 8 meses. En cambio, cuando fue medial, las posibilidades de una tendencia al valgo fueron >0,85 (u 85%) ya al tomar la primera imagen, i.e., poscirugía; y cuando fue lateral, esta posibilidad se modifica y profundiza según el tiempo transcurrido hasta la imagen lograda en el paciente. Conclusión: Se observó una relación marcada y continua entre el punto de entrada del clavo endomedular y la alineación de la tibia después de la consolidación ósea.

Abstract The authors report on the behavior of C60 molecules adsorbed on graphene (Gr) monolayers grown on Rh(110), studied by means of scanning tunneling microscopy and spectroscopy under ultra‐high vacuum conditions. Fullerene molecules form a well‐ordered close packed hexagonal layout with an intermolecular distance of ≈1 nm. As demonstrated from the experimental data, the molecular packing direction of C60 is locally close to being aligned with the quasi‐1D moiré patterns formed by graphene on the metal support. Moreover, for certain orientations of graphene on Rh(110), the underlying moiré pattern appears superimposed on the molecular assembly. However, the analysis of the highest occupied molecular orbital and the lowest unoccupied molecular orbital structures and the differential conductance curves of C60 on Gr/Rh(110) suggest a weak molecule–substrate interaction, similar to other 2D material/metal interfaces. All these observations can imply that the moiré structures of Gr/Rh(110) play a central role in the arrangement of C60, but without modifying its electronic properties, which makes this Gr/Rh(110) system a singular platform for C60 adsorption. Complementarily, the structural properties of multilayer growth of C60 on Gr/Rh(110) are also investigated.

Abstract Background Mortality due to COVID-19 is high, especially in patients requiring mechanical ventilation. The purpose of the study is to investigate associations between mortality and variables measured during the first three days of mechanical ventilation in patients with COVID-19 intubated at ICU admission. Methods Multicenter, observational, cohort study includes consecutive patients with COVID-19 admitted to 44 Spanish ICUs between February 25 and July 31, 2020, who required intubation at ICU admission and mechanical ventilation for more than three days. We collected demographic and clinical data prior to admission; information about clinical evolution at days 1 and 3 of mechanical ventilation; and outcomes. Results Of the 2,095 patients with COVID-19 admitted to the ICU, 1,118 (53.3%) were intubated at day 1 and remained under mechanical ventilation at day three. From days 1 to 3, PaO2/FiO2 increased from 115.6 [80.0–171.2] to 180.0 [135.4–227.9] mmHg and the ventilatory ratio from 1.73 [1.33–2.25] to 1.96 [1.61–2.40]. In-hospital mortality was 38.7%. A higher increase between ICU admission and day 3 in the ventilatory ratio (OR 1.04 [CI 1.01–1.07], p = 0.030) and creatinine levels (OR 1.05 [CI 1.01–1.09], p = 0.005) and a lower increase in platelet counts (OR 0.96 [CI 0.93–1.00], p = 0.037) were independently associated with a higher risk of death. No association between mortality and the PaO2/FiO2 variation was observed (OR 0.99 [CI 0.95 to 1.02], p = 0.47). Conclusions Higher ventilatory ratio and its increase at day 3 is associated with mortality in patients with COVID-19 receiving mechanical ventilation at ICU admission. No association was found in the PaO2/FiO2 variation.

Summary: Background: The clinical heterogeneity of COVID-19 suggests the existence of different phenotypes with prognostic implications. We aimed to analyze comorbidity patterns in critically ill COVID-19 patients and assess their impact on in-hospital outcomes, response to treatment and sequelae. Methods: Multicenter prospective/retrospective observational study in intensive care units of 55 Spanish hospitals. 5866 PCR-confirmed COVID-19 patients had comorbidities recorded at hospital admission; clinical and biological parameters, in-hospital procedures and complications throughout the stay; and, clinical complications, persistent symptoms and sequelae at 3 and 6 months. Findings: Latent class analysis identified 3 phenotypes using training and test subcohorts: low-morbidity (n=3385; 58%), younger and with few comorbidities; high-morbidity (n=2074; 35%), with high comorbid burden; and renal-morbidity (n=407; 7%), with chronic kidney disease (CKD), high comorbidity burden and the worst oxygenation profile. Renal-morbidity and high-morbidity had more in-hospital complications and higher mortality risk than low-morbidity (adjusted HR (95% CI): 1.57 (1.34-1.84) and 1.16 (1.05-1.28), respectively). Corticosteroids, but not tocilizumab, were associated with lower mortality risk (HR (95% CI) 0.76 (0.63-0.93)), especially in renal-morbidity and high-morbidity. Renal-morbidity and high-morbidity showed the worst lung function throughout the follow-up, with renal-morbidity having the highest risk of infectious complications (6%), emergency visits (29%) or hospital readmissions (14%) at 6 months (p

Floral phenotypes impact interactions between plants and pollinators. Here, the authors show that Moricandia arvensis displays discrete seasonal plasticity in floral phenotype, with large, lilac flowers attracting long-tongued bees in spring and small, rounded, white flowers attracting generalist pollinators in summer.

In this study, nanocomposites based on polypropylene are synthesized by the in situ polymerization of propene in the presence of mesoporous SBA-15 silica, which acts as a carrier of the catalytic system (zirconocene as catalyst and methylaluminoxane as cocatalyst). The protocol for the immobilization and attainment of hybrid SBA-15 particles involves a pre-stage of contact between the catalyst with cocatalyst before their final functionalization. Two zirconocene catalysts are tested in order to attain materials with different microstructural characteristics, molar masses and regioregularities of chains. Some polypropylene chains are able to be accommodated within the silica mesostructure of these composites. Thus, an endothermic event of small intensity appears during heating calorimetric experiments at approximately 105 °C. The existence of these polypropylene crystals, confined within the nanometric channels of silica, is corroborated by SAXS measurements obtained via the change in the intensity and position of the first-order diffraction of SBA-15. The incorporation of silica also has a very significant effect on the rheological response of the resultant materials, leading to important variations in various magnitudes, such as the shear storage modulus, viscosity and δ angle, when a comparison is established with the corresponding neat iPP matrices. Rheological percolation is reached, thus demonstrating the role of SBA-15 particles as filler, in addition to the supporting role that they exert during the polymerizations.

The Segura Hydrographic Demarcation (DHS), in Southeastern Spain, is an area of hydric deficit caused by low and irregular rainfall and a dense population. In this region water scarcity is a burning issue that polarizes society for or against different models of ensuring water supply. Given the current demand for water throughout Spain, desalination has been used to increase water supply, and as insurance against drought. Ten seawater desalination plants and hundreds of brackish aquifer desalination plants treat water in the Southeast of the Iberian Peninsula, both for human consumption and for irrigation, contributing to economic, energetic, processual and economic aspects of territorial organization in the Southeast of Spain. This article reviews debates over desalination, water transfers, and the best way to meet water demands in that region. While desalination allows an increase in water supply, dependence on that source increases energy costs and may lead to mistaken assumptions among users about water scarcity and availability. Keywords: seawater desalination, brackish aquifer desalination, human water supply, social debate, irrigation, Southeast of Spain

La guerra química, biológicay radiológica constituye una potencial amenaza que debe ser tenida en cuenta en el diseño de buques de guerra. Desde la perspectiva de los países latinoamericanos, se hace necesario entender la dinámica de este tipo de guerra, teniendo en cuenta que, aunque en términos de riesgo la probabilidad actual de estar sometidos a ataques con armas de este tipo es baja, el impacto que generaría un potencial ataque sería muy alto. Por ello, se busca investigar los diferentes factores que obligan a considerar la defensa contra guerra química, biológica y radiológica en el diseño de buques de guerra, los componentes que deben ser tenidos en cuenta para desarrollar dicha capacidad de defensa, así como la selección de normas y/o estándares que puedan ser acogidos para alcanzar la capacidad deseada