Microcontroller-Based Sinusoidal Voltage Generation for Electrical Bio-Impedance Spectroscopy Applications

A sinusoidal voltage wave generator is proposed based on the use of micro- processor digital signals with programmable duty-cycles, with application to real-time Electrical Cell-substrate Impedance Spectroscopy (ECIS) assays in cell cultures. The working principle relies on the time convolution of the programmed microcontroller (μC) digital signals. The expected frequency is easily tuned on the bio-impedance spectroscopy range [100 Hz, 1 MHz] thanks to the μC clock frequency selection. This system has been simulated and tested on the 8 bits μC Arduino™ Uno with ATmega328 version. Results obtained prove that only three digital signals are required to fit the general specification in ECIS experiments, below 1% THD accuracy, and show the appropriateness of the system for the real-time monitoring of this type of biological experiments.Spanish founded Project: TEC 2013- 46242-C3-1-P: Integrated Microsystem for Cell Culture AssaysFEDE

Tourism as a tool for economic development in poor countries

Most scientific literature have begun to argue that while tourism growth can influence the economic and sociocultural development of society, the impacts of tourism do not always lead to increased economic development, especially in less developed countries. However, in spite of these limitations, some international organizations defend that tourism has become an economic activity that many poor countries are considering or implementing as part of their efforts to alleviate poverty. In this context, the aim of this research has been to determine whether the economic growth experienced in the poor countries over the last decade influences an increase in their level of economic development. The results prove that, in poor countries, tourism growth does not influence the level of economic development, which supports the claims of some of the most recent scientific literature, and contradicts the position of many international organizations that make an indiscriminate use of tourism as a tool to enhance economic development in the poorest countries

Tributación de actividades turísticas: revisión de los 50 principales destinos turísticos

Public authorities have played a key role in tourism competitiveness, as this agent is obliged to provide certain infrastructure and services. This has led to incurring certain additional costs that may be financed by contributions from the implementation of fiscal instruments. The objective of the present work is to identify the tourist taxes implemented in the 50 main world tourist destinations. To do this, different official, national and international sources have been consulted. Tourist taxes have been identified in 49 of the 50 main tourist destinations; and have been configured, therefore, as an effective instrument for obtaining the necessary financingLos poderes públicos han desempeñado un papel clave en la competitividad turística, al recaer sobre este agente la obligación de proporcionar determinadas infraestructuras y servicios. Ello ha provocado incurrir en determinados costes adicionales, ante lo cual, la implantación de instrumentos fiscales puede contribuir a obtener la financiación necesaria. El objetivo del presente trabajo es identificar los tributos de carácter turístico implantados en los cincuenta principales destinos turísticos mundiales. Para ello, se han consultado distintas fuentes oficiales, nacionales e internacionales. Se han identificado tributos de carácter turístico en 49 de los 50 principales destinos turísticos; configurándose, por tanto, como un instrumento eficaz para obtener la financiación necesari

Tourists’ willingness to pay to improve sustainability and experience at destination

Consolidated tourism destinations face certain challenges derived from aspects such as new client demands, growing competition, the problems of overtourism and tourism-phobia, and the modernization of infrastructures. The creation of taxes and/or public fees that affect tourism activities is one potential option for public managers facing these difficulties. The objective of this study is to determine tourists’ willingness to pay in order to increase the income of public managers to create these types of policies. The study was carried out in Andalusia, a region of southern Spain with high rates of tourism, which received some 32.4 million tourists in 2019. A survey was conducted on 1068 tourists at the main tourism arrival points of this region. First, factors influencing the willingness and amount to be paid by each tourist were identified; for this, distinct statistical techniques were used (binary logistic regression and decision trees). Second, the sensitivity of tourism demand was analyzed with regard to the establishment of these types of taxes and public fees, concluding that tourism demand is inelastic in the face of a moderate increase in prices resulting from the creation of taxes and/or public fees

Reaction Dynamics for the Systems 7Be,8B + 208Pb at Coulomb Barrier Energies

In this contribution we describe the first results obtained for the investigation of the elastic scattering process in the reactions induced by the Radioactive Ion Beams 7Be and 8B on a 208Pb target at Coulomb barrier energies. The experimental data were analyzed within the framework of the optical model in order to extract the total reaction cross section. The comparison with data available in literature for reactions induced on 208Pb by light ions in the mass range A = 6-8 shows that the loosely-bound 8B has the largest reactivity

Effect of mycoviruses on the virulence of Fusarium circinatum and laccase activity

Producción CientíficaLaccase enzymes (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) play a major role in the degradation of phenolic compounds such as lignin. They are common in fungi and have been suggested to participate in host colonization by pathogenic fungi. Putative mycoviruses have recently been isolated from the causal agent of pine pitch canker disease, Fusarium circinatum Nirenberg & O'Donell. In this study, the effects of single and double mycoviral infections on laccase activity, growth rate and pathogenicity were investigated in fourteen F. circinatum strains. Extracellular laccase activity was analyzed by the Bavendamm test, image processing and a spectrophotometric method. Mycelial growth, in vivo pathogenicity and seedling survival probability were also determined in Monterrey pine (Pinus radiata D. Don) seedlings. The findings showed that (i) mycelial growth of isolates from the same fungal population was homogeneous, (ii) the presence of mycovirus appears to increase the virulence of fungal isolates, (iii) co-infection (with two mycoviruses) caused cryptic effects in fungal isolates, and (iv) laccases embody a possible auxiliary tool in fungal infection. The prospects for biocontrol, the adaptive role of F. circinatum mycoviruses and the importance of laccase enzymes in host colonization are discussed.Ministerio de Economía, Industria y Competitividad (Project AGL2012-39912

Investigation of Coulomb dipole polarization effects on reactions involving exotic nuclei

We have analyzed elastic scattering angular distributions and total reaction cross sections of the exotic nuclei Li9,11 on Pb208, at energies below and above the Coulomb barrier. For this purpose, we have used an optical potential with no adjustable parameters, composed by the nuclear São Paulo potential, derived from the nonlocal nature of the interaction, and the Coulomb dipole polarization potential, derived from the semiclassical theory of Coulomb excitation. Within this formalism, we identified an unusual long-range absorption for the Li11+Pb208 system, which is dominated by the Coulomb interaction. We compare it to the absorption mechanisms observed for He6+Pb208 which, unlike those of Li11+Pb208, take place at small interacting distances, where both Coulomb and nuclear interactions are important. The proposed approach shows to be a fundamental basis to study reactions involving exotic nuclei

Monitoring Muscle Stem Cell Cultures with Impedance Spectroscopy

The aim of this work is to present a new circuit for the real-time monitoring the processes of cellular growth and differentiation of skeletal myoblast cell cultures. An impedance spectroscopy Oscillation-Based technique is proposed for the test circuit, converting the biological system into a voltage oscillator, and avoiding the use of very high performance circuitry or equipment. This technique proved to be successful in the monitoring of cell cultures growth levels and could be useful for determining the degree of differentiation achieved, of practical implications in tissue engineering.Ministerio de Economía y Competitividad TEC2013-46242-C3-1-

Analysis of digital competence of educators (DigCompEdu) in teacher trainees: the context of Melilla, Spain

This study was partly funded by the autonomous city of Melilla, Spain, through PROMESA and the UGR-Enterprise Foundation.The Spanish autonomous city of Melilla, located in northwest Africa, has one of the highest academic failure and abandonment rates in Europe. An effective way to improve this situation would be to improve students’ digital competence. In order to do so, teachers must have competent digital skills themselves and also be able to teach them. To determine teachers’ level of digital competence, the Spanish adaptation of the European Framework for Digital Competence of Educators was used to analyse the self-assessment responses of teachers in training at the Faculty of Education and Sport Sciences in Melilla, Spain. Several quantitative techniques were used to analyse data collected from a questionnaire based on the items in the framework. Indicators were given to each competence using a factor analysis to contrast differences between undergraduate and postgraduate students. Correlations between some of the students’ characteristics and the competences were estimated using OLS. The results show students’ self-assessment level of digital competence in different areas and differences between the bachelor’s and master’s programmes. Digital competence gaps were also detected in teacher training, especially in security. The conclusions highlight the need to improve digital security and facilitate a higher level of digital skills in line with the framework. Indeed, more hours of training in digital competence are required while taking into account the educational context and the technological, pedagogical and content knowledge needed to teach. Equally, the same skills must be developed by educators in order for them to transmit digital competence to their students and support them in educational centres.autonomous city of Melilla, Spain, through PROMESAUGR-Enterprise Foundatio