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Gestión de los recursos de origen animal entre los grupos del Paleolítico Medio de la península ibérica: Ambrona (Soria), Cuesta de la Bajada (Teruel) y Abrigo de Navalmaíllo (Pinilla del Valle, Madrid)
No full textEn este trabajo analizamos diacrónicamente conjuntos faunísticos de yacimientos ibéricos con tecnología del Paleolítico Medio con la intención de caracterizar las estrategias cinegéticas y de aprovechamiento de recursos animales de estos grupos. Para ello hemos analizado con metodología zooarqueológica, tafonómica y espacial los yacimientos de Ambrona, Cuesta de la Bajada y del Abrigo de Navalmaíllo. El estudio de estos yacimientos nos ha permitido definir la funcionalidad de las ocupaciones humanas, identificándose en Ambrona y en Cuesta de la Bajada kill/butchering sites y en el Abrigo de Navalmaíllo un campamento de caza. La comparación de los datos extraídos con otros conjuntos peninsulares nos ha servido para identificar que las estrategias cinegéticas de los grupos del Paleolítico Medio antiguo serían virtualmente idénticas a las de los últimos neandertales. Sin embargo, detectamos algunas diferencias entre el comportamiento de los grupos en función de si manejaban, o no, la pirotecnología.Recent studies showed that the Middle Palaeolithic is a technocomplex that appears in European contexts in chronologies up to MIS 9 or 10, or even MIS 11. The Iberian Peninsula is an area where archaeological sites with Middle Palaeolithic technology have been found in ages up to MIS 10. In recent years, an important effort has been made in this region in order to characterize the technological features of these assemblages, and at the same time different zooarchaeological and taphonomic analyses had been developed trying to interpret other subsistence issues. In this PhD dissertation we have analysed the faunal assemblages of Middle Palaeolithic sites with a diachronic point of view with the main aim of characterising the strategies of hunting and exploitation of animal resources by these populations. For this purpose, we have analysed the sites of Ambrona, Cuesta de la Bajada and Abrigo de Navalmaíllo using a zooarchaeological, taphonomic and intra-site spatial methodology. The detailed study of these sites has allowed us to characterize the functionality of these occupations: the level J of Ambrona and the levels CB1, CB2 and CB3 of Cuesta de la Bajada are interpreted as kill/ butchering sites while the level F-D of the Navalmaíllo Rock Shelter can be typified as a specialized hunting camp. Comparison of our data with other sites on the Iberian Peninsula allows us to identify that the hunting strategies of the early Middle Palaeolithic groups were practically the same to those of the last Neanderthals. However, we detected some differences between the behaviour of the groups depending on whether they controlled the fire or not.Esta investigación ha sido financiada, principalmente, a través de la adjudicación de un contrato predoctoral de la Junta de Castilla y León, cofinanciado por el Fondo Social europeo (Orden EDU/574/2018 [BDNS 376062]). La estancia predoctoral realizada en la Universidad de Colonia se ha realizado disfrutando de una ayuda para movilidad de alumnos de doctorado de la Universidad de Burgos, cofinanciada por Banco Santander S. A. (BDNS 571617). Esta Tesis Doctoral no habría podido llevarse a cabo sin la colaboración presupuestaria de distintos proyectos de investigación: CEN154P20, cofinanciado por el Fondo Europeo de Desarrollo Regional y la Junta de Castilla y León PGC2018-093612-B-100, financiado por el Fondo Europeo de Desarrollo Regional y el Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación. H2019/HUM-5840, financiado por la Comunidad de Madrid y el Fondo Social Europeo. PGC2018-094125-B-100, financiado por el Fondo Europeo de Desarrollo Regional y el Ministerio de Ciencia e Innovación – Agencia Estatal de Investigación
New strategies for the synthesis of Raman enhancement substrates: The origin of EC-SOERS
No full textLa espectroscopía Raman es una técnica de análisis molecular que durante muchos años ha generado interés por su capacidad de proporcionar huellas dactilares de diversas moléculas, pero que se ha visto limitada en gran parte por su falta de sensibilidad. Para solventar este problema, durante décadas los investigadores han recurrido a fenómenos de aumento de la dispersión Raman, como el famoso fenómeno SERS. En la presente tesis se realiza un estudio profundo del fenómeno EC-SOERS: un fenómeno de aumento Raman reportado en 2018 en la Universidad de Burgos, cuya principal característica es que ocurre durante la oxidación de un electrodo metálico, lo cual hace difícil la identificación de las estructuras responsables de dicho aumento Raman. Los resultados de la tesis arrojan luz sobre las estructuras responsables del fenómeno EC-SOERS, al mismo tiempo que generan nuevas e interesantes ideas para la generación de sustratos de aumento Raman basados en nuevos materiales semiconductores. Junto con el mencionado estudio del fenómeno EC-SOERS, la tesis también describe el desarrollo de distintos dispositivos y herramientas útiles en el estudio de distintos procesos electroquímicos. Ejemplo de estos dispositivos son una nueva aproximación para la realización de experimentos espectroelectroquímicos sobre sustratos de cobre, o una nueva celda de espectroelectroquímica bidimensional para realizar experimentos en capa fina con control micrométrico del espesor de la misma
Electric DQ0 Library Model for Smart Grid Simulation
No full textThis paper addresses the pressing need for advanced simulation tools in electric phasor modeling and Smart Grid-Power to X systems. The motivation for this study stems from the critical importance of enhancing the balance between performance and the detailed dynamic representation of the system behavior in the simulations. The identified problem lies in the absence of a comprehensive framework that seamlessly integrates electric phasor DQ0 components into a multi-purpose object-oriented environment. The primary objective of this research is to develop and introduce two simulation libraries, centered around the core component, Electric_DQ0. These libraries aim to establish a robust phasor-based framework, incorporating essential electric components such as sources, loads, branches, power converters, and electric machines. The main goal is to enable dynamic frequency and voltage simulations, particularly focusing on transients in alternators and facilitating Voltage and Frequency Rate of Change analysis during power production-demand imbalances. The libraries were developed within a versatile object-oriented environment, employing the Electric_DQ0 components as the foundation. Through ports, these components transmit turning frequencies, supporting the simulation of dynamic frequency and voltage. The libraries are designed to comprehensively support monophasic and triphasic systems, encompassing delta and wye connections, with a flexible neutral configuration under both balanced and unbalanced conditions. A validation case is presented to demonstrate the tool’s ability to accurately reproduce predictions when compared to one of the most widely used electrical modeling tools in the market. A study case is also presented to evaluate the toolkit’s capabilities. The study sets a specific power demand to fulfill, utilizing diverse energy sources. The obtained results showcase the libraries’ effectiveness in addressing the identified problem, providing valuable insights into their performance and applicability in real-world scenarios. The results demonstrate the efficacy of the proposed framework, delivering accurate outcomes within a reduced execution time.This paper is part of the project “Optimal Management of the Power-to-H2-to-Power Cycle in Real Time (OptiMaPH2P)” Ref TED2021-131220B-I00, funded by the spanish government MCIN/AEI/10.13039/501100011033 and the European Union funds “NextGenerationEU”/PRTR
Polímeros inteligentes con aplicación en biomedicina, seguridad civil y control alimentario
No full textEsta memoria describe el diseño, desarrollo y caracterización de sensores poliméricos con aplicación en biomedicina, seguridad civil y control alimentario. En el ámbito de la biomedicina, se ha llevado a cabo un sensor para el diagnóstico de Covid-19 en muestras de saliva. En seguridad civil, se han descrito polímeros inteligentes como sensores colorimétricos para la lucha contra la falsificación. En el marco del control alimentario se han desarrollado sensores poliméricos para la detección de Zn(II) y Cu(II) en piensos y mostos, respectivamente.This work describes the design, development, and characterization of polymeric sensors for applications in biomedicine, civil security, and food control. In biomedicine, a sensor has been developed for the diagnosis of COVID-19 in saliva samples. In civil security, intelligent polymers have been described as colorimetric sensors for anticounterfeit applications. Finally, in the field of food control, polymer sensors have been developed for the detection of Zn(II) in pet food and Cu(II) in grape must.Ministerio de Ciencia, Innovación y Universidades por su financiación mediante la ayuda predoctoral (PRE2018-086240) con referencia del proyecto MAT2017-84501-R
Extracción con agua subcrítica y ultrafiltración para la obtención de pecto-oligosacáridos a partir de residuos de piel cebolla
No full textIn this work the purification by ultrafiltration using tubular ceramic membranes of pectic
oligosaccharides (POS) extracted from onion skin wastes (OSW) was studied.
In the first stage of the work, subcritical water was used to promote the hydrolysis of OSW and
obtain a liquid hydrolysate rich in POS. For this purpose, three different combinations of
temperature and extraction time (115 ºC – 180 min; 125 ºC – 150 min and 135 ºC – 90 min)
were used in a batch extractor at 25 bar. In order to consider the combined effect of the
temperature and the extraction time, the severity factor (log Ro) was calculated, resulting to be
in the range 2.88 to 3.29. The best results in terms of POS concentration (5643 ± 84 mg/L) in
the hydrolysate was obtained in the experiment carried out at 125 ºC (log Ro = 3.16). It was
also possible to demonstrate that the composition of the liquid hydrolysate was strongly
influenced by the extraction conditions: the higher the severity factor the higher the
concentration of impurities (organic acids, HMF and furfural) and higher the POS hydrolysis
rate. This was demonstrated by the increased concentration of free monosaccharides
(glucose, xylose, galactose and arabinose) and the decrease in the POS molecular weight.
In the second stage of the work, the aim was to study the separation of POS from the impurities
formed during the subcritical water hydrolysis stage, using an ultrafiltration process in
diafiltration mode. For this purpose, a 50 kDa tubular membrane was firstly used (Tami
Industries, active layer of TiO2 and 132 cm2 of effective area). The fouling mechanism,
hydraulic resistance and the purification extent were studied. Important differences in the
permeate flux (J) were observed as a function of the subcritical water hydrolysate composition.
The permeate flux obtained when filtering the 115 ºC hydrolysate decreased dramatically at
the beginning of the experiment to achieve a constant value, whereas the hydrolysates
obtained at 125 and 135 ºC exhibited a different behaviour: an initial fast decline of the
permeate flux followed by a slower continuous decrease. This result for 125 and 135 ºC
hydrolysates can be justified due to the effects of the membrane fouling (fouling mechanism
was cake layer formation, according to Hermia’s model). Using this 50 kDa membrane, the
POS recovery was 76 % (115 ºC hydrolysate), 58 % for the 125 ºC hydrolysate and 56% for
the 135 ºC hydrolysate. In all the cases, a complete removal of the impurities was achieved
after the dilution factor of 3.5.
To complete the purification experiments, the effect of the removal of the colloidal matter (by
centrifugation) present in the 125 ºC hydrolysate was studied using two different membranes
(50 and 5 kDa). In the hydrolysate, it was observed the formation of a black precipitate that
was responsible for the membrane fouling, hindering the filtration process. The removal of this
colloidal matter, which did not affect the POS fraction, was responsible for the reduction of the
colour of the hydrolysate by 60 % and the promotion of the filtration process (a faster removal
of the impurities was achieved) without loss of the POS fraction. Finally, when a 5 kDa
membrane was used, the retention of the POS fraction was higher than 80 % in comparison
to the 60 % obtained for the 50 kDa membrane.El trabajo presentado ha sido desarrollado en el seno del Grupo de Investigación Biotecnología Industrial y Medioambiental, reconocido por la UBU (GIR-UBU BIOIND) y por la Junta de Castilla y León como Unidad de Investigación Consolidada UIC-128, en el marco de los siguientes proyectos de investigación:
PID2020-116716RJ-I00 - Tecnologías de fluidos presurizados para la valorización de subproductos de la industria agroalimentaria: recuperación de pectina y otros compuestos bioactivos de alto valor, financiado por la Agencia Estatal de Investigación.
PDC2022-133443-I00 – Diseño de un prototipo para la extracción de bioproductos con agua subcrítica, financiado por el Ministerio de Ciencia e Innovación.
TED2021-129311B-I00 - Tecnologías verdes basadas en el empleo de fluidos presurizados para valorizar biomasa lignocelulósica mediante la producción de furfural, financiado por el Ministerio de Ciencia e Innovación.
BU050P20 - Valorización de la fracción proteica de subproductos de la industria agroalimentaria de Castilla y León mediante tecnologías de fluidos presurizados, financiado por la Junta de Castilla y León y el Fondo Europeo de Desarrollo Regional (FEDER)
Plan parcial sector S-12
No full textEl presente documento “Plan Parcial Sector S-12 Burgos” tiene como objetivo desarrollar las determinaciones
contenidas en el Plan General de Ordenación Detallada de Burgos en el suelo urbanizable del sector S-12 situado
en Burgos
The Complex Relationship between the Board and Web Transparency in Nonprofit Organizations
Get PDFThis research analyzes the relationship between board composition and web transparency in nonprofit organizations (NPOs). The board is conceived as a governance mechanism that not only monitors management but also gives voice to all stakeholders and considers accountability—and, more specifically, web transparency—as a key instrument for the NPO’s legitimization. To conduct this study, we manually built a database from the CVs of 793 directors of 67 Spanish non-governmental development organizations and we use fuzzy set comparative qualitative analysis (fsQCA). Our results indicate that board composition (size, independence, gender diversity, and presence of directors with financial or NPOs’ expertise) influences transparency and that, depending on the organizational size and legal form, there are different board configurations that lead to high transparency. Generally, NPOs should include experts in nonprofit sector and more female members on their boards to increase transparency.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was supported by UAM—Comunidad de Madrid Research Project for Young Researchers (SI3-PJI-2021-00276)
A new shape-conformable battery concept: The 3D printed injectable battery filled with semi-solid electrodes
Get PDFShape-conformable batteries are of high interest for a variety of portable electronics. In this work, a new manufacturing concept for cost-effective shape-conformable batteries based on the combination of additive manufacturing (AM) technology and semi-solid electrodes (SSEs) is proposed. The manufacturing process consists in two steps. Firstly, the electrochemical cell is printed by stereolithography-based technique (SLA) and subsequently assembled. In a second step, flowable SSEs are injected into the cells by a double injection mechanism to introduce both SSEs in parallel. While syringe outlets, cell inlets and shape of the cell are found to play an important role in the injection process, formulation of the SSEs are observed to influence the rheological and electrochemical properties. For the proof of concept, a battery having the shape of the logo of our university is fabricated using Zn-based and MnO2-based SSEs achieving high utilization rate (>150 mAh) and acceptable cycle stability (0.45% h−1) and thus showing the feasibility of the proposed shape-conformable injectable battery. The manufacturing process is finally extended to other battery chemistries leading to improved cycling stability and confirming the versatility of the manufacturing concept.The authors acknowledge the financial support by “Fundación la Caixa”, under agreement LCF/PR/PR18/51130007. The authors also acknowledge the financial support by the Spanish Ministry of Science and Innovation and NextGenerationEU (TED2021-131651B–C21) and Ramón y Cajal award (Ministry of Science and Innovation and European Social Funds, RYC2018-026086-I). This work was supported by the Regional Government of Castilla y León (Junta de Castilla y León) and by the Ministry of Science and Innovation MICIN and the European Union NextGenerationEU/PRTR
Designing bilayered composite films by direct agar/chitosan and citric acid-crosslinked PVA/agar layer-by-layer casting for packaging applications
No full textPackaging is a crucial tool for reducing food waste and enhancing product competitiveness. Fossil fuel-based plastics, mostly used for food packaging, account for nearly 40% of global plastic waste. To address this issue, this study developed a layer-by-layer casting technique to create novel bilayered plastic composites with distinct agar/chitosan and PVA/agar layers. Film's properties, such as thickness, plasticity, and tensile strength, were affected by adjusting the volume of the layers. The elongation at break was positively related to the presence of citric acid (up to 30 wt%) as a crosslinker. The chitosan-rich first layer provided better UV-light blocking potential and opacity, which were beneficial in the prevention of lipid oxidation. Increasing the second layer by 40–60% substantially reduced the light absorption, while the colors were proportional to the citric acid content. The FT-IR band at 1713 cm−1 indicated an increase in C=O ester groups with crosslinker content. The hydrophobicity of the films was enhanced by the chitosan-rich layer. XRD supported intramolecular and intermolecular hydrogen bonding, whereas the micrographs revealed tightly bound structure between layers. The results corroborated that the inclusion of agar in the formulations increased the stability of the film, making it ideal for various packaging applications.This work was supported by the European Commission, Horizon 2020 program through the Marie-Curie Individual Fellowship (H2020-MSCA-IF-2019), with regards to the ALGWAS-BIOR project (Grant agreement number 898804). This work was also supported by European Union H2020-LC-SC3-2020-NZE-RES-CC, NMBP-16-2020-GA 953152 and DT-NMBP-04-2020 Projects and Ministerio deand Ministerio de Ciencia, Innovación y Universidades CTQ(QMC) RED 2018-102471-T MultiMetDrugs Network (Spain)
Synthesis of 4‐Furan‐ and 4‐Pyrrol‐3‐yl‐2H‐chromenes from Naturally‐occurring Compounds by Gold(I)‐Catalyed Domino Reactions
No full textA gold-catalyzed cascade double cyclization reaction has been designed to synthesize heterobiaryl compounds such as furanyl and pyrrolyl 2H-chromenes from bis(alkynyl)-1,2-diols and 1,2-amino alcohols. The starting materials are readily available from biomass platform molecules such as α-hydroxy acids and α-amino acids. The process involves an initial heterocyclodehydration step enabling the formation of the furan or pyrrole ring, followed by an alkyne hydroarylation to form the chromene core.We gratefully acknowledge Ministerio de Ciencia e Innovación MCIN/AEI/10.13039/501100011033 (PID2020–115789GB-C21), and Junta de Castilla y León and FEDER (BU049P20) for financial support. M.S. and L.R. thank Junta de Castilla y León (Consejería de Educación) and Fondo Social Europeo for predoctoral contracts. S.S.-P. thanks a Ramón y Cajal (RYC2021-031533-I) contract funded by MCIN/AEI/10.13039/501100011033 and European Union “NextGenerationEU”/PRTR