Industrial production of microalgae by an eco-sustainable process: light utilization efficiency and nutrient recycling

This Ph. D. project is aimed to improve the efficiency and the sustainability of microalgal cultivation in view of large-scale biofuels production. Experiments as well as modeling and process simulation were used to investigate: i) the light utilization efficiency in algal photobioreactors and ii) different strategies for the recovery and recycling of nutrients. First of all, microalgal growth in continuous photobioreactors is modeled in order to identify optimum working conditions that allow maximum productivity, accounting for light intensity and regime, as well as for axial dispersion. Then, the integration of photovoltaic (PV) technologies with photobioreactors is studied as a possible technical solution to improve the photons utilization per surface area. In this regard, experiments applying either standard, low-cost silicon solar cells or a novel organic dye-sensitized semi-transparent photovoltaic module on the reactor surface are reported. An energetic and economic analysis of microalgal cultivation in a photovoltaic greenhouse, with the roof partially covered by PV panels is also presented. Two different strategies for nutrients recovery and recycling are investigated, namely flash hydrolysis (FH) of whole algal biomass and anaerobic digestion (AD) of lipid-extracted residues. The nutrients-rich aqueous phases produced by FH of two different algal species (Scenedesmus sp. and Nannochloropsis gaditana) are used to assess the growth performances of the respective algae in this medium. As an alternative to the direct recycling of the aqueous hydrolysate, the possibility of precipitating the nutrients in stable fertilizers is also reported. The biogas production from AD of lipid-extracted microalgae is evaluated, and the subsequent growth rate in the liquid digestate was compared to that obtained in standard synthetic medium. Finally, the experimental data gained from FH and AD are used to implement process simulations with the aim of evaluating the material and energy balances and to assess the feasibility on a large-scale

Temporal issues in e-learning research: A literature review

Time is a critical factor in learning, but time is also a very complicated factor that has many facets. Time can be as follows: time needed to prepare a course or lesson (ie, for the instructor to gather materials and design/develop a course or lesson), time needed to follow a course or lesson (ie, the planned, nominal study time that the institution allots for the learner in minutes and/or hours per day or the number of weeks per semester/year that the course encompasses), lifetime of a course (ie, how long a course can be used before it needs to be revised and/or is out of date), time that a student needs for study (ie, both in and out of class), time that an instructor needs and/or uses to teach a course (ie, the number of hours per day both during and beyond the “school” day for preparation, correction, feedback and marking of products and exams), “transaction” time costs (eg, the amount of travel time needed to attend a course or to log into an online course) and even time that a learner can make effective use of the knowledge gained (ie, half-life of the information in a course). Time can also be seen as an effectiveness factor (ie, the amount learned in a specific time period; learning more in the same time period is more effective learning) and/or efficiency factor (ie, the amount of time needed to learn something; learning the same amount in less time is more efficient learning). Time can, finally, be seen as a solitary factor or as part of a temporal pattern inwhich other factors play a role such aswork time, family time, down time, etc

Proceso de estudio en enseñanza universitaria a distancia con uso de nuevas tecnologías

It seems particularly important to capture (he interaction which is set up in our educational practice in order to promote the significant learning of contents and through which we can learn about the perception of the student in the learning process. In this learning at a distance, there is an important role for individual study. The present paper looks at how students from different degree courses pursue their learning objectives, and thus provides an X-ray through this opaque individual learning process. We look at the need to explore the nature of the process and to specify indicators of analysis and explanation in order to continue our investigation in depth. With this in mmd, we first establish which individual study techniques and sequences of these students use in order to achieve their learning objectives. We then look at their effectiveness by examining different variables.En el marco de la educación universitaria a distancia parece especialmente importante captar la interacción que se establece para facilitar un aprendizaje significativo de los contenidos y a partir de la cual interesa conocer la percepción del estudiante en el proceso educativo. Dado que el estudio personal realizado a distancia ocupa un lugar preferente en este proceso, en el presente artículo se pretende ofrecer una radiografía que contribuya a revelar un poco mds este proceso opaco de estudio personal que los estudiantes de diferentes carreras siguen para conseguir los objetivos de aprendizaje. Inicialmente se establecen para este fin actuaciones de estudio individuales y concatenadas que el estudiante lleva a cabo para alcanzar dichas metas de aprendizaje y su efectividad con relación a diferentes variables

Breaching Learners’ Social Distancing through Social Media during the COVID-19 Pandemic

Higher education has been shifted toward blended learning during the COVID-19 pandemic. An increase in social media usage intensity and reduced face-to-face interaction due to the COVID-19 pandemic urged instructional communication researchers to revisit the dynamics of learners’ group development in terms of their socialization and academic performance during the COVID-19 crisis. This research aimed to determine the mediating role of social media sociability between face-to-face socialization and academic performance of higher education students in blended learning environments during the COVID-19 pandemic. It was also the aim of the study to determine the moderating effect of social media usage intensity on social media sociability. A cross-sectional survey was conducted with the students (n = 340) enrolled in science teacher education departments of universities in Pakistan. Partial least squares structural equation modeling (PLS-SEM) was used for multivariate analysis. Results revealed that face-to-face socialization gave an essential start to develop a learning group. However, when face-to-face socialization was reduced due to the COVID-19 pandemic, it was mediated by social media usage in blended learning environments to increase their socialization and academic performance during the crisis. The findings of the study are useful for higher education institutions to adopt social media strategies for students’ socialization during the crisis

Sustainability Analysis of Hydrogen Production Processes: a Comparison Based on Sustainability Indicators

Hydrogen is a versatile energy carrier and storage medium that may be employed in a variety of applications. It may be produced using different processes. In this work, process simulation is used to obtain material and energy balances for each process investigated, as well as for the evaluation of capital and maintenance costs. Process simulation outcomes are then used to estimate three key performance indicators focusing on sustainability issues: the energy return of energy invested, the levelized cost of hydrogen and the life cycle assessment. We compared several hydrogen generation processes, each denoted by a unique colour code: (i) green hydrogen, produced by electrolysis of water using electricity from renewable sources, (ii) grid hydrogen, produced by electrolysis using grid electricity, (iii) grey hydrogen, produced from natural gas using steam reforming and (iv) blue hydrogen, like grey one, but coupled with carbon capture and storage. In conclusion, the most sustainable hydrogen production method is the green hydrogen, produced by water electrolysis

Development and validation of a life skills evaluation tool for online learning based on the framework of the capability approach

The promotion of life skills in learners is especially challenging in distance and online environments where the learners’ physical absence from the classroom hinders the evaluation of these types of skills. Due to the great challenges brought about by this physical absence, there is a lack of empirical studies attempting to examine life skills in web-based scenarios. This study therefore aimed to fill the existing gap in operationalizing the role of life skills for online learning through the capability approach (CA). This exploration was conducted under the umbrella of Nussbaum’s version of the CA. Specifically, our study contributes by devising an integrative and comprehensive teaching and learning framework for open educational practices based on the CA, and by introducing a new instrument that has been adapted to this context. Methodologically, the design and validation of the instrument involved a four-stage process. First, Nussbaum’s list of central human capabilities was operationalized for online learning. Then, in the second stage, a qualitative content validity check was performed to verify whether the instrument was appropriate and comprehensive in terms of what it was intended to measure. The aim of the third and fourth stages was to quantitatively assess the reliability and validity of the questionnaire. For the third stage, the instrument was pre-tested through a modified version of the Q-sort method. In the fourth stage, non-parametric tests were used to validate the internal consistency and content validity of the questionnaire. Thirty experts from the areas of online education, philosophy, and statistics took part in these stages.Financed by Beijing municipal educational science foundation No. AHDB19030.info:eu-repo/semantics/publishedVersio

Support through Social Media and Online Class Participation to Enhance Psychological Resilience

Social support was an important factor in minimizing the effect of social isolation during the COVID-19 pandemic lockdown. This research aimed to study the role of online class participation and social media usage to link the social support available from family and friends to psychological resilience among pre-service special education teachers against the negative psychological effects of the COVID-19 pandemic lockdown. A survey was conducted with 377 pre-service special needs education (SNE) teachers enrolled at universities in Pakistan. Partial least square structural equation modeling (PLS-SEM) was applied using Smart-PLS 3.2.8. Results revealed that social media and online class participation played a mediating role between social support and psychological resilience in the pre-service special needs education (SNE) teachers studied. Teacher education institutions can devise strategies to develop social media platforms for student socialization during an emergency to help build resilience against the negative psychological effects of social isolation. Future studies could be conducted to adapt instructions and curricula to social media environments for education in an emergency.Peer reviewe

The Effect of Verbal and Iconic Messages in the Promotion of High-Quality Mountain Cheese: A Non-Hypothetical BDM Approach

To ensure the sustainable development of mountain livestock farming, the adequate remuneration of high-quality dairy products is fundamental. In this sense, communication strategies aimed at promoting mountain products and ensure better positioning and higher market prices are fundamental. The present research seeks to expand the literature regarding consumers’ willingness to pay for mountain foods by using an online real auction experiment aimed at evaluating the premium price that consumers are willing to pay for summer over winter mountain cheese, depending on the information provided concerning the taste anticipation or animal welfare. The results showed an overall small premium price given to the higher quality summer cheese; this could be, partially, due to a generally low degree of consumer knowledge about mountain dairy farming. With reference to communication strategies, the results provide evidence about the effectiveness of the rational messages founded upon sensorial characteristics and the anticipated taste of cheese. In addition, this study explored that adding a logo had no main effect on the price premium participants were willing to pay. This may be due to the fact that logos and claims, having a lower information content, are more indicated to lead the choice of consumers with a higher level of awareness. In the conclusion section, policy and agribusiness implications of the findings are provided

EduZinc: A tool for the creation and assessment of student learning activities in complex open, online and flexible learning environments

This article describes the development of an application for the grading and provision of feedback on educational processes. The too, named EduZinc, enables instructors to go through the complete process of creating and evaluating the activities and materials of a course. The application enables for the simultaneous management of two teaching-related aspects: (a) creation of individualized learning products (activities, tests and exams) and (b) automatic grading (for every learning product; automated creation of student, class, and competency-based reports; and delivery of personalized reports to students, instructors and tutors). The system also has a series of warnings in place to notify instructors and tutors when a student is falling behind. As a means to reward the efforts made during the course, the program keeps relevant statistics, notifying when a student is excelling in the course

Le politiche per lo sviluppo Locale della Regione Piemonte (1994 - 2006)

Analisi delle politiche- Indice #7- Executive Summary/Sintesi della ricerca #11- Introduzione. Il contesto e gli obiettivi della ricerca #15- Parte prima. Politiche di sviluppo locale e progettazione integrata a livello regionale #21- Programmi integrati: dalla riqualificazione urbana allo sviluppo locale #23- Progetti Integrati di Sviluppo Turistico d'Area e Progetti Integrati di Sviluppo Turistico #42- Programmi di Iniziativa Comunitaria Leader #58- Patti territoriali #91- Progetti Integrati d'area #106- Programmi Integrati di Sviluppo Locale (PISL) #124- Programmi Territoriali Integrati (PTI) #147- Uno sguardo d'insieme #171- Parte Seconda. L'approfondimento empirico #181- Il caso del Pinerolese #183- Il caso del Verbano #204- Parte Terza. Conclusioni e suggerimenti per le politiche pubbliche #229- Riferimenti bibliografici #23