Sistema Regional de Información
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Robert A. Kaster, C. Suetoni Tranquilli De Vita Caesarum libros VIII et De Grammaticis et Rhetoribus librum, recognouit breuique adnotatione critica instruxit Robert A. Kaster, Oxford Classical Text, Oxford University Press, 2016, lxxx+487 pp., ISBN: 978-01-9871-379-1 Robert A. Kaster, Studies on the text of Suetonius’ De uita Caesarum, Oxford University Press, 2016, xii+332 pp., ISBN 978-01-9875-847-1.

José Luis Moralejo, Tácito, Vida de Julio Agrícola. Del origen y situación de los germanos. Diálogo sobre los oradores. Prólogos, texto revisado, traducciones, notas e índices, Madrid: Consejo Superior de Investigaciones Científicas, 2017, ccclxii+173 pp. [dobles], ISBN 978-84-00-10219-7, e-ISBN 978-84-00-10220-3.

Alessandro Garcea– Marie-Karine Lhommé – Daniel Vallat (eds.), Fragments d’érudition. Servius et le savoir antique. ?Spudasmata. Studien zur Klassischen Philologie und ihren Grenzgebieten’, 168. Hildesheim-Zürich- New York: Georg Olms Verlag, 2016, 535 pp., ISBN 978-3-487-15433-6.

The present work explains the current efforts to develop an accessible, profitable and clean technology for the utilization of lignocellulosic residues to obtain ethanol and other derivatives through fermentative processes of the different sugars and by-products that result from the degradation of cellulose. Biomass, whose main component is cellulose, is the most abundant raw material on the planet, and its rational use would produce enormous economic and ecological benefits. Acid hydrolysis of cellulose is expensive and pollutant. Therefore, it is intended to escalate to industrial levels the enzymatic hydrolysis of cellulose, by means of enzymes produced by several species of fungi (Trichoderma, Aspergillus, etc.), bacteria and other organisms, and looking for other industrially useful sources for a biorefinery. It is ecologically beneficial, and potentially much less expensive, but it is necessary to reproduce to an industrial scale the activity observed in laboratory conditions. Genetic engineering helps to diversify the production of enzymes or increase the amount produced by organisms. The complete enzymatic hydrolysis uses cellulolytic enzymes: endoglucanases, exoglucanases and ß-glucosidases, hardly produced in industrially interesting amounts by a single organism, being necessary to combine several of them. In addition, techniques such as recycling or recirculation of enzymes within the bioreactor would help an integral use. Another line of research is the mathematical modeling of the production of enzymatic crudes with simulators such as Superpro Designer and others. The great variety of products obtained from plant biomass, from ethanol to citric acid, lactic acid, uronic acids, acetic acid, etc., support the economic, social, industrial and ecological benefits that this technology would generate.

At present the study of the problems of the university novel teacher is important for the generation of proposals that contribute to their professional development. The proposed objective allowed to establish the problems of the new university teaching staff in their investigative function. The research responds to a qualitative approach. The subjects investigated were 68 new teachers from the Central University of Ecuador. In the methodology, the analysis of interviews was used, through a structured base guide with the intention of understanding and interpreting the meaning of the stories of the protagonists. The results achieved, allowed to reveal that, of the total of participants, it was found that 65.84% of novice teachers, said that their problems in the investigative function, are due to institutional constraints. While a 29.19% of protagonists, said their problems respond to personal constraints. Finally, 4.97% of participants mentioned having no problems. It was concluded that the problems of the university novel faculty in their investigative functions are: the low research culture that prevails in the university community, the lack of support from the institutional authorities to allocate required budgets and the lack of academic training that teachers have in the methodology of scientific research.

Concrete, a mixture of Portland cement, water and aggregates, is commonly used in the construction industry with high percentage of in-situ fabrication. The proportions of each mixture component is very important to ensure its quality (i.e., compressive strength). Nowadays, several empirical mixture design procedures are utilized; however, the majority of them are based on equations, tables and/or correlations, without considering past experiences and/or experimental data. The present study illustrates the application of fuzzy logic theory for developing a model for estimating concrete mixture proportions by weight, without admixtures. The selected independent variables (input data) were those that are commonly used for concrete mixture design. Historical experimental data and concrete technician’s experience were utilized for creating membership functions (FMs) and fuzzy rules. Mamdani fuzzy inference system (SIL) was used for developing the model since this allows to have several outputs (e.g., water – cement ratio and aggregates). The results indicate that the SIL is able to estimate concrete mixture proportions very well (R2=95.1%); however, the model can be improved as long as new knowledge of the system is available. Furthermore, the model is able to use stored data and technical personal experience in order to develop particular models for each project.

Nowadays, the need to develop materials that promote efficient energy savings has been one of the transcendental topics studied around the world. With this novelty, the present investigation determined that the inclusion of Strontium Aluminate co-doped with Europium and Dysprosium in binders based on Portland cement not only produces the photoluminescence phenomenon but also improves its mechanical properties; through the accomplishment of diverse physical-mechanical laboratory tests like the compressive strength in test pieces, besides chemical analyzes with XRF in different samples of concrete. The research further found that the 0.3:1 ratio of the compound to the cement allow obtaining the most optimal phosphorescent effect. Finally, by means of the economic analysis it is shown that the cost/benefit of applying the photoluminescent cementitious composite as a long-term road sign is much more cost effective than the use of the conventional luminaire.

The mining company MINEREICIS SA located in the canton of Ponce Enríquez province of Azuay dedicated to the extraction of gold and copper bearing minerals has detected gold in the final tailings, additionally in the flotation concentrates it has a percentage of arsenic, which penalizes its commercialization. Having explained this, a research was carried out to optimize the operation from the geometallurgy. The geometallurgy characterization of the deposit, provides the information for the evaluation of resources, to define the methods of exploitation and the technique of benefit of minerals. The mineralogical characterization of the deposit was carried out by sampling methodically the veins for the formation of a composite to submit them to the metallurgical tests. All this information does not derive from the variables that geometallurgy uses for the optimization of the mining process. The hypothesis is: conducting a technical - scientific research will optimize the metallurgical process of recovery of gold and concentrate. Referential Framework: mining geology of the Bella Rica District, current status of the Benefit Plant. Theoretical Framework: parameters of the veins, comminution operations.