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Estado de la cuestión sobre la perspectiva de género y enseñanza de la Historia y las Ciencias Sociales en España
No full textLa adopción de enfoques coeducativos, y la promoción de una educación en y
para la igualdad de género, implican transformar el currículo docente
tradicional, con el propósito de superar las bases constructivas androcéntricas
del conocimiento histórico y social, y de incorporar ‘miradas polisémicas’ en
la comprensión e interpretación de la realidad social
Blockchain-based architecture for the control of logistics activities: Pharmaceutical utilities case study
Get PDFLogistics services involve a wide range of transport operations between distributors and clients. Currently, the large number of
intermediaries are a challenge for this sector, as it makes all the processes more complicated. To face that problem, we propose
a system that uses smart contracts to remove intermediaries and speed up logistics activities. Our new model combines smart
contracts and a multi-agent system in a single platform to improve the current logistics system by increasing organization,
security and getting rid of several human intermediaries to automate its processes, making distribution times significantly
faster. Also, with this kind of approach, it is possible to apply penalties to parties that do not comply with the terms of using
this platform.This work was developed as part of ‘Virtual Ledger Technologies DLT/Blockchain y Cripto-IOT sobre organizaciones virtuales de agentes ligeros y su aplicación en la eficiencia en el transporte de última milla’, ID SA267P18, project cofinanced by Junta Castilla y León, Consejería de Educación and FEDER funds. Also, the research work carried out by Yeray Mezquita is supported by the pre-doctoral fellowship from the University of Salamanca and Banco Santander
From Propargylic Alcohols to Substituted Thiochromenes: gem- Disubstituent Effect in Intramolecular Alkyne Iodo/hydroarylation
Get PDFThis work describes the 6-endo-dig cyclization of Saryl propargyl sulfides to afford 2H-thiochromenes. The substitution at the propargylic position plays a crucial role in allowing
intramolecular silver-catalyzed alkyne hydroarylation and Niodosuccinimide-promoted iodoarylation. Additionally, a PTSAcatalyzed thiolation reaction of propargylic alcohols was developed
to synthesize the required tertiary S-aryl propargyl ethers. The
applicability of merging these two methods is demonstrated by
synthesizing the retinoic acid receptor antagonist AGN194310.Junta de Castilla y León
and FEDER (BU291P18 and BU049P20) and Ministerio de
Ciencia e Innovación and FEDER (CTQ2016-75023-C2-1-P)
for financial support. The project leading to these results has
received funding from “la Caixa” Foundation, under Agreement
LCF/PR/PR18/51130007> (CAIXA-UBU001). N.V.,
F.M.-L., and S.S.-P. thank Junta de Castilla y León and FSE
and FEDER for predoctoral (N.V. and F.M.-L.) and
postdoctoral (S.S.-P.) contracts, respectively
Maximizing the freeze-dried extract yield by considering the solvent retention index: extraction kinetics and characterization of Moringa oleifera leaves extracts
Get PDFA complete chemical characterization of Moringa oleifera leaves was carried out showing a high content of extractives. Extraction kinetics of bioactive compounds present in this fraction were performed by conventional and ultrasound assisted extraction (UAE). A 50% (v/v) hydroalcoholic mixture led to the highest total phenolic compounds yield by conventional solvent extraction, 29.5 ± 0.3 mg per gram of moringa leaves. UAE did not bring any improvement when using hydroalcoholic mixtures probably due to the physical properties of the ethanol aqueous mixtures that affect the UAE performance, such as viscosity and vapor pressure of the mixture. The retention index of the different solvents in the raffinate phase was determined revealing the highest retention index for water, 9.5, and a continuous decrease by increasing ethanol concentration. Retention index is a key parameter in a solvent extraction process since it determines the number of stages in an industrial separation process and it is not usually reported in bioactive compounds extraction. Solvent extraction capacity and the retention index determined the final freeze-dried extract yield.Junta de Castilla y León (JCyL) and the European Regional Development Fund (ERDF) [grantnumbers BU301P18 and BU050P20]; and the Agencia Estatalde Investigación [grant number AEI/10.13039/501100011033]
Paleointensity Results From Pliocene Lavas of the Lesser Caucasus Obtained Using the Multispecimen Parallel Differential pTRM Method: A Comparison With Thellier- Thellier and IZZI Data
Get PDFWe report paleointensity results obtained with the multispecimen method (MSP) over the Pliocene sequence of Apnia (Georgia) which records a polarity reversal. Paleointensity determinations with the multispecimen technique were performed on 12 flows with the original (MSP-DB) and the domain-state corrected (MSP-DSC) protocol. Eight MSP-DSC determinations passed the proposed quality criteria. To obtain highly reliable data through the agreement between intensity values from different methods, MSP results were combined with paleointensities from a previous study with Thellier-type methods and especially strict selection criteria (RCRIT) on same flows (Sánchez-Moreno et al., 2020). Application of this multimethod procedure resulted in three new paleointensities including both MSP and Thellier-type results and an additional one obtained with two different Thellier-type methods, yielding one paleointensity of 36.9 µT in the normal-polarity, and three paleointensities between 19.2 and 24.1 µT in the reverse-polarity section. Additionally, Thellier-type data have been reinterpreted in this study with more flexible criteria (TTP) and the results combined with the MSP data. As a result, four flows yield paleointensities including MSP and Thellier-type determinations and seven include paleointensities obtained with two different Thellier-type methods. Results range from 37.2 and 44.3 μT in the normal-polarity and from 12.5 to 24.6 μT in the reverse-polarity section. Comparison of results from the four flows yielding multimethod determinations applying RCRIT criteria with those from the same flows under TTP criteria yields no significant difference in paleointensity values and their experimental uncertainty. Thus, application of a multimethod approach supports the possibility of using TTP criteria.Project PID2019-105796/10.13039/501100011033 (Agencia Estatal de Investigación, Spain), project BU066U16 (Junta de Castilla y León, Spain) and pre-doctoral grant BES-2013-064060 (MINECO, Spain). MCR acknowledges funding from the Fulbright Commission and the Spanish Ministry of Science, Innovation and Universities for a research stay at Hawaii University at Manoa. AG is grateful to the financial support given by DGAPA-PAPIIT IN101717. At Montpellier laboratory, the FUReMAG rapid furnace construction was supported by the French National Agency for Research (ANR-12-BS06-0015)
An Integrated Paleomagnetic, Multimethod- Paleointensity, and Radiometric Study on Cretaceous and Paleogene Lavas From the Lesser Caucasus: Geomagnetic and Tectonic Implications
Get PDFSixteen rhyolitic and dacitic Cretaceous and Paleocene-Eocene lavas from the Lesser Caucasus have been subjected to paleomagnetic and multimethod paleointensity experiments to analyze the variations of the Earth's magnetic field. Paleointensity experiments were performed with two methods. Thellier-type experiments with the IZZI method on 65 specimens (nine flows) yielded 15 successful determinations and experiments with the multispecimen method on 14 samples (seven flows) yielded two successful determinations. The joint analysis of the results obtained with both methods produced a mean FuK = (19.9 ± 3.7) µT for upper Cretaceous and FPg = (20.7 ± 3.3) µT for Paleogene sites. Low virtual axial dipole moments for the Cretaceous (3.4 × 1022 Am2) and Paleogene (3.5 × 1022 Am2) samples support the idea of a lower average dipole moment during periods of stable polarity of the Earth magnetic field. Mean flow paleomagnetic directions did not match expected upper Cretaceous to Paleogene directions calculated from the European Apparent Polar Wander Path. While inclination results roughly agreed with expected values, a group of sites showed nearly North-South paleodeclinations (D = 1.1° ± 14.2°), and another group displayed eastward deviated paleodeclinations (D = 72.9° ± 26.6°). These results suggest the occurrence of nearly vertical-axis rotations, probably as a result of continental collision since Oligocene. In addition to paleomagnetic and palaeointensity analyses, new K-Ar absolute age determinations have been performed on three of the studied sites, yielding Late Cretaceous ages (78.7 ± 1.7, 79.7 ± 1.6, and 83.4 ± 1.8 Ma (2σ)).Project PID2019-105796GB-100/AEI/10.13039/501100011033 (Agencia Estatal de Investigación, Spain). M. Calvo-Rathert acknowledges funding from the Fulbright Commission and the Spanish Ministry of Science, Innovation, and Universities for a research stay at Hawaii University at Manoa. A. Goguitchaichvili acknowledges financial support from UNAM-PAPIIT no. IN101920. N. García-Redondo acknowledges financial support from Junta de Castilla y León and the European Research Development Fund (ERDF). EHB acknowledges financial support for laboratory maintenance and measurements to SOEST-HIGP and National Science Foundation grants. These is SOEST 11143 and HIGP 2420 contribution
Review and Perspectives for Effective Solutions to Grand Challenges of Energy and Fuels Technologies via Novel Deep Eutectic Solvents
Get PDFSustainable technologies applied to energy-related applications should develop a pivotal role over the next decades. Therefore, the development of new materials for old processes has merged as a central research line lately. Deep eutectic solvents (DESs) have been recently considered alternative and economic task-specific solvents for many chemical and environmental processes. The low-cost production of DESs production from natural sources and their tunable properties, such as neat null toxicity and biodegradability, make these solvents suitable candidates for various processes within the green chemistry framework. Considering the millions of possible DES combinations yet to be explored, a detailed review of DES research’s current status that can elaborate on the structure–property relationship is an essential task to identify the missing links and strong points on DES research. Thus, this review work focuses on the recent research efforts on the utilization of DES on chemical processes, with the purpose of elucidation on gas capture/separation, fuel desulfurization, biodiesel production, and water treatment processes and provides a deeper understanding on outstanding scientific questions and identifies promising new research directions that involve DESs.Ministerio de Ciencia, Innovación y Universidades (Spain, Project No. RTI2018-101987-B-I00) and Western Michigan University Research Fund (No. 11-1211410-4850)
Improve teaching with modalities and collaborative groups in an LMS: an analysis of monitoring using visualisation techniques
No full textMonitoring students in Learning Management Systems (LMS) throughout the teaching–
learning process has been shown to be a very effective technique for detecting
students at risk. Likewise, the teaching style in the LMS conditions, the type of student
behaviours on the platform and the learning outcomes. The main objective of
this study was to test the effectiveness of three teaching modalities (all using Online
Project-based Learning -OPBL- and Flipped Classroom experiences and differing
in the use of virtual laboratories and Intelligent Personal Assistant -IPA-) on Moodle
behaviour and student performance taking into account the covariate "collaborative
group". Both quantitative and qualitative research methods were used. With
regard to the quantitative analysis, differences were found in student behaviour in
Moodle and in learning outcomes, with respect to teaching modalities that included
virtual laboratories. Similarly, the qualitative study also analysed the behaviour patterns
found in each collaborative group in the three teaching modalities studied. The
results indicate that the collaborative group homogenises the learning outcomes, but
not the behaviour pattern of each member. Future research will address the analysis
of collaborative behaviour in LMSs according to different variables (motivation and
metacognitive strategies in students, number of members, interactions between students
and teacher in the LMS, etc.).This study is part of the project funded by the Consejería de Educación de la Junta de Castilla y León to the recognised research group DATAHES Grant Number BU032G19.Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL
Fouling control of submerged and side-stream membrane bioreactors based on the statistical analysis of mid-term assays
Get PDFThe response surface methodology has been applied to study reversible and irreversible fouling rates caused by anaerobic sludge in membrane bioreactors, with the aim of controlling membrane fouling by adjusting filtration conditions. The challenge of obtaining statistically significant results of long-term fouling by means of mid-term assays has been addressed. The individual and combined effects of the filtration flux, backwashing intensity, gas sparging and crossflow velocity on membrane fouling, were analyzed in two types of membranes: an external tubular membrane and a submerged hollow fiber membrane. In the external membrane, the reversible fouling rate was as low as 0.27 ± 0.10 mbar/min, depending mainly on the filtration flux and gas sparging. However, the principal control parameter of the irreversible fouling rate was the crossflow velocity, reaching 2.12 ± 1.75 1012 m−2 in terms of increase of resistance per cubic meter filtered by square meter of membrane. In the submerged membrane, the irreversible fouling rate was quite lower, 0.78 ± 0.40 mbar/d, despite the reversible fouling rate was higher, 1.26 ± 0.42 mbar/min. In this case, the irreversible fouling depended mainly on the backwashing frequency despite the reversible fouling was more affected by the filtration flux and gas sparging. Hence, the approach used to control the reversible fouling rate does not involve mitigating irreversible fouling on both submerged and external membranes. This study provides a methodological basis for the selection of site-specific operating conditions, under which sustainable operation of membrane bioreactors could be achieved.TCUE 2018–2020 cofounded by European Regional Development Fund (ERDF) and Junta de Castilla y León (Spain) and the inestimable collaboration of Campofrío Frescos and Grupo Ecoalia