Reproductive potential of a vole pest (Arvicola scherman) in Spanish apple orchards

Fossorial water voles, Arvicola scherman, feed on tree roots causing important damages in European apple orchards. Since the intensity of crop damage produced by rodents ultimately depends on their inherent capacity to increase their population, the main goal of this study was to determine the reproductive potential of the subspecies A. scherman cantabriae in apple orchards from Asturias (NW Spain), where voles breed over the whole year. Our results were compared with those reported for the subspecies A. scherman monticola from the Spanish Pyrenees (where reproduction ceases in winter). Sexual characteristics, body condition, relative age class and number of embryos were recorded from 422 females caught in apple orchards along two years. We found pregnant females all along the year, which were able to produce a high number of litters per year (7.30) although litter size was relatively moderate (first year: 3.87 embryos/female; second year: 3.63 embryos/females). The potential number of pups per female and year (first year: 28.25; second year: 26.50) was substantially higher than that reported for Pyrenean voles, what is probably related with differences in the length of the breeding season and in life histories between subspecies. In our population, the number of implanted embryos correlated positively with the body condition of the mother. Our results reveal that management efforts should not be seasonal as they used to be so far and invite to explore the physiological consequences of management practices

D-branes, axion monodromy and large-field inflation

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física Teórica. Fecha de lectura: 14-09-201

Development of membrane coated electrodes for the electroreduction of CO2 in alkaline media

RESUMEN: Las emisiones de gases de efecto invernadero procedentes de distintas actividades industriales son una de las principales contribuciones antropogénicas al calentamiento global y al cambio climático. El dióxido de carbono (CO2) es el más relevante de estos gases, por lo que resulta imprescindible fomentar la generación de energía mediante fuentes renovables, así como implementar tecnologías de captura y utilización de CO2 (CCU). En este contexto, la electrorreducción de CO2 (CO2R) es una tecnología involucrada tanto en la utilización de CO2 como en el desarrollo de fuentes de energía renovables, concretamente como sistema de almacenamiento de energía. La CO2R consiste en transformar el CO2 por vía electroquímica en productos de interés para la industria, como hidrocarburos o alcoholes. El proceso se lleva a cabo en un reactor electroquímico que consta de distintos elementos, siendo los principales el cátodo, electrodo en el que tiene lugar la reacción de reducción del CO2, el ánodo, donde se desarrolla una oxidación como contrarreacción, y el medio electrolítico por el que se transporta la carga eléctrica entre los dos electrodos, en forma de iones. Este último elemento puede ser un líquido, principalmente disoluciones acuosas, pero también existe la posibilidad de emplear electrolitos sólidos que, además de permitir el transporte de cargas iónicas entre electrodos, dificultan el paso de reactivos o productos del cátodo al ánodo, mejorando así el rendimiento del reactor. Estos electrolitos sólidos son las membranas de intercambio iónico (IEM). De esta forma, esta tesis se centra en explorar los roles de la IEM en la CO2R, tanto su papel como electrolito sólido y separador de electrodos, como su aplicación como recubrimiento superficial del electrodo, para proteger el material catalítico y controlar las limitaciones de transporte en la reacción, mejorando así la selectividad de la reacción. Este diseño de electrodo se ha denominado membrane coated electrode (MCE).ABSTRACT: One of the main anthropogenic contributions to global warming and climate change is the emission of greenhouse gases coming from different activities, e.g. energy production from fossil fuels. Carbon dioxide (CO2) is the most relevant of all these gases. Thus, it is mandatory to promote the energy production from renewable sources and to implement carbon capture and utilization (CCU) processes. In this regard, CO2 electroreduction (CO2R) is a technology involved in both, CO2 utilization and the development of a renewable electricity mix, as an energy storage system. This technology is able to electrochemically transform CO2 into diverse products like hydrocarbons or alcohols. CO2R takes place in an electrochemical reactor which combines different elements: the cathode, the electrode where the reduction reaction is carried out, the anode, the counter electrode at which an oxidation occurs, and the electrolyte which transports the ionic charges. The latter element could be liquid, typically aqueous solutions, but it is also possible to employ solid electrolytes which allows the ionic transfer between electrodes while avoiding products crossover. These solid electrolytes are the ion exchange membranes (IEM). This thesis is focused in exploring the roles of the IEM in CO2R. Three different functions of the membrane were studied: as solid polyelectrolyte and barrier between electrodes, but also its use as overlayer of the cathode was introduced, leading to the development of membrane coated electrodes (MCE). This electrode structure was proposed to protect the catalyst from material losses and degradation, and to control the mass transfer limitations to improve the selectivity of the reaction as well.Esta tesis ha sido elaborada en el grupo de investigación Desarrollo de Procesos Químicos y Control de Contaminantes (DePRO) del Departamento de Ingenierías Química y Biomolecular de la Universidad de Cantabria. El trabajo de investigación realizado ha sido financiado por el Ministerio de Ciencia e Innovación a través de los proyectos CTQ2016-76231-C2-1-R “Diseño multiescala de procesos de captura y utilización de dióxido de carbono” y PID2019- 108136RB-C31 “Optimización de captura de CO2 con membranas y procesos de utilización para acoplar la electrovalorización de CO2 a oxidaciones relevantes bajo criterios de sostenibilidad”. Además, el autor de esta tesis, Aitor Marcos Madrazo, ha disfrutado de un contrato predoctoral para la formación de personal investigador (FPI) del Ministerio de Ciencia e Innovación, con referencia BES-2017-080795. Este contrato incluía una ayuda para la movilidad que permitió al autor realizar una estancia breve en el Fraunhofer IGB (Alemania). Por todo ello, queremos expresar nuestro más sincero agradecimiento a las mencionadas instituciones y entidades

Uncertainty of biomass stocks in Spanish forests: a comprehensive comparison of allometric equations

Biomass and carbon content are essential indicators for monitoring forest ecosystems and their role in climate action, but their estimation is not straightforward. A typical approach to solve these limitations has been the estimation of tree or stand biomass based on forest inventory data, using either allometric equations or biomass expansion factors. Many allometric equations exist, but very few studies have assessed how the calculation methods used may impact outcomes and how this impact depends on genera, functional group, climate or forest structural attributes. In this study we evaluate the differences in biomass estimates yielded by the most widely used biomass equations in Spain. We first quantify the discrepancies at tree level and among the main forest tree species. We observed that the divergences in carbon estimations between different equations increased with tree size, especially in the case of hardwoods and for diameters beyond the range used to calibrate the equations. At the plot level, we found considerable differences between the biomass values predicted using different methods (above 25% in one out of three plots), which constitutes a warning against the uncritical choice of equations to determine biomass or carbon values. The spatial representation of the differences revealed geographical patterns related to the dominance of fast-growing species such as Eucalyptus or Pinus pinaster, with a minor effect of forest structure, and almost no effect of climate. Finally, we observed that differences were mostly due to the data source rather than the modelling approach or equation used. Based on our results, BEF equations seem a valid and unbiased option to provide nation-level estimations of carbon balance, although local equations should preferably be used if they are available for the target area.This work was funded by the LIFE CLIMARK project (LIFE16 CCM/ES/000065) and by the Spanish State Research Agency through the UMBRACLIM project (PID2019-111781RB-I00). The authors would like to thank Lluis Coll for helpful discussions during the conceptualization of the study and Pere Gelabert for his help in map design and creation. Special thanks to Miquel de Caceres, Jordi Vayreda and Jordi Martinez-Vilalta for the creation of the Catalan Forestry Lab and the gathering and release of the IEFC data

QoS-aware Metamorphic Testing: An Elevation Case Study

Elevators are among the oldest and most widespread transportation systems, yet their complexity increases rapidly to satisfy customization demands and to meet quality of service requirements. Verification and validation tasks in this context are costly, since they rely on the manual intervention of domain experts at some points of the process. This is mainly due to the difficulty to assess whether the elevators behave as expected in the different test scenarios, the so-called test oracle problem. Metamorphic testing is a thriving testing technique that alleviates the oracle problem by reasoning on the relations among multiple executions of the system under test, the so-called metamorphic relations. In this practical experience paper, we report on the application of metamorphic testing to verify an industrial elevator dispatcher. Together with domain experts from the elevation sector, we defined multiple metamorphic relations that consider domain-specific quality of service measures. Evaluation results with seeded faults show that the approach is effective at detecting faults automatically

Towards a Taxonomy for Eliciting Design-Operation Continuum Requirements of Cyber-Physical Systems

Software systems that are embedded in autonomous Cyber-Physical Systems (CPSs) usually have a large life-cycle, both during its development and in maintenance. This software evolves during its life-cycle in order to incorporate new requirements, bug fixes, and to deal with hardware obsolescence. The current process for developing and maintaining this software is very fragmented, which makes developing new software versions and deploying them in the CPSs extremely expensive. In other domains, such as web engineering, the phases of development and operation are tightly connected, making it possible to easily perform software updates of the system, and to obtain operational data that can be analyzed by engineers at development time. However, in spite of the rise of new communication technologies (e.g., 5G) providing an opportunity to acquire Design-Operation Continuum Engineering methods in the context of CPSs, there are still many complex issues that need to be addressed, such as the ones related with hardware-software co-design. Therefore, the process of Design-Operation Continuum Engineering for CPSs requires substantial changes with respect to the current fragmented software development process. In this paper, we build a taxonomy for Design-Operation Continuum Engineering of CPSs based on case studies from two different industrial domains involving CPSs (elevation and railway). This taxonomy is later used to elicit requirements from these two case studies in order to present a blueprint on adopting Design-Operation Continuum Engineering in any organization developing CPSs

Analysis of professional perceptions relating to the effectiveness of codes of ethics for journalists in Spain

The methodology used in the present study is based on quantitative content analysis using the survey technique. This technique makes it possible to obtain empirical data on various key aspects of the profession that are determining factors in ascertaining Spanish journalists’ views of one of the instruments of accountability that is external to the media: general ethical codes. The results show that Spanish journalists are largely confident in the effectiveness of ethical codes in their profession. Likewise, it was seen that variables such as age, professional experience or the media with which they work influence the perceptions that professionals have of such instruments. If we understand journalism as a profession whose mission is to guarantee the citizenship their right to information, it is essential to be familiar with the tools provided by the profession itself in order to be accountable to the public regarding this professional mission. Hence the importance of instruments of accountability and the perceptions of the professionals themselves regarding their effectiveness

Use of Chitosan as Copper Binder in the Continuous Electrochemical Reduction of CO2 to Ethylene in Alkaline Medium

This work explores the potential of novel renewable materials in electrode fabrication for the electrochemical conversion of carbon dioxide (CO2) to ethylene in alkaline media. In this regard, the use of the renewable chitosan (CS) biopolymer as ion-exchange binder of the copper (Cu) electrocatalyst nanoparticles (NPs) is compared with commercial anion-exchange binders Sustainion and Fumion on the fabrication of gas diffusion electrodes (GDEs) for the electrochemical reduction of carbon dioxide (CO2R) in an alkaline medium. They were tested in membrane electrode assemblies (MEAs), where selectivity to ethylene (C2H4) increased when using the Cu:CS GDE compared to the Cu:Sustainion and Cu:Fumion GDEs, respectively, with a Faradaic efficiency (FE) of 93.7% at 10 mA cm−2 and a cell potential of −1.9 V, with a C2H4 production rate of 420 µmol m−2 s−1 for the Cu:CS GDE. Upon increasing current density to 90 mA cm−2, however, the production rate of the Cu:CS GDE rose to 509 µmol/m2s but the FE dropped to 69% due to increasing hydrogen evolution reaction (HER) competition. The control of mass transport limitations by tuning up the membrane overlayer properties in membrane coated electrodes (MCE) prepared by coating a CS-based membrane over the Cu:CS GDE enhanced its selectivity to C2H4 to a FE of 98% at 10 mA cm−2 with negligible competing HER. The concentration of carbon monoxide was below the experimental detection limit irrespective of the current density, with no CO2 crossover to the anodic compartment. This study suggests there may be potential in sustainable alernatives to fossil-based or perfluorinated materials in ion-exchange membrane and electrode fabrication, which constitute a step forward towards decarbonization in the circular economy perspective.This research was funded by the Spanish Ministry for Science and Innovation, grant numbers PID2019-108136RB-C31, PID2019-108136RB-C32, PID2020-112845RB-I00 and EIN2020-112319. A.M.M. also acknowledges the Ministry for the Early Stage researcher contract (FPI grant no. BES-2017-080795)