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  • PublicationOpen Access
    Alliaceae-derived supplementation improves the severity of COVID-19 symptoms among elderly nursing home residents
    (MDPI, 2024) Vázquez-Blanquiño, Alberto; Pérez-Rodríguez, Lucía; Alberola-Romano, Ana; Martínez-Pérez, María; Baños, Alberto; Gómez Fernández, Germán Orlando; Gracián, Carlos; Fonollá, Juristo; García, Federico; Ciencias; Zientziak
    This study investigates the effect of daily consumption of a concentrated garlic and onion extract on COVID-19 symptoms among elderly nursing home residents. Volunteers consumed a daily capsule of the concentrated powder rich in organosulfur compounds over 36 weeks during lunch. The incidence and severity of COVID-19 symptoms between the treatment and control groups were compared, along with monitoring the safety of consumption, incidence of other diseases, and medicine usage. The treatment group showed a significant reduction in both the number and severity of COVID-19 symptoms compared to the control group, with no significant adverse effects observed. No significant reduction in symptom duration was detected. This study provides preliminary evidence that concentrated garlic and onion extract may aid in the treatment of COVID-19 among older adults. These findings suggest potential public health benefits, emphasizing the need for further research to explore the immunomodulatory properties of these natural compounds.
  • PublicationOpen Access
    Prediction of protein targets in ovarian cancer using a ru-complex and carbon dot drug delivery therapeutic nanosystems: a bioinformatics and µ-FTIR spectroscopy approach
    (MDPI, 2024) Nesic, Maja D.; Dučić, Tanja; Gemović, Branislava; Senćanski, Milan; Algarra González, Manuel; Gonçalves, Mara; Stepic, Milutin; Popovic, Iva; Kapuran, Đorđe; Petkovic, Marijana; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    We predicted the protein therapeutic targets specific to a Ru-based potential drug and its combination with pristine and N-doped carbon dot drug delivery systems, denoted as RuCN/CDs and RuCN/N-CDs. Synchrotron-based FTIR microspectroscopy (µFTIR) in addition to bioinformatics data on drug structures and protein sequences were applied to assess changes in the protein secondary structure of A2780 cancer cells. µFTIR revealed the moieties of the target proteins’ secondary structure changes only after the treatment with RuCN and RuCN/N-CDs. A higher content of α-helices and a lower content of β-sheets appeared in A2780 cells after RuCN treatment. Treatment with RuCN/N-CDs caused a substantial increase in parallel β-sheet numbers, random coil content, and tyrosine residue numbers. The results obtained suggest that the mitochondrion-related proteins NDUFA1 and NDUFB5 are affected by RuCN either via overexpression or stabilisation of helical structures. RuCN/N-CDs either induce overexpression of the β-sheet-rich protein NDUFS1 and affect its random coil structure or interact and stabilise its structure via hydrogen bonding between -NH2 groups from N-CDs with protein C=O groups and –OH groups of serine, threonine, and tyrosine residues. The N-CD nanocarrier tunes this drug’s action by directing it toward a specific protein target, changing this drug’s coordination ability and inducing changes in the protein’s secondary structures and function.
  • PublicationOpen Access
    Progress and perspectives in the catalytic hydrotreatment of bio-oils: effect of the nature of the metal catalyst
    (American Chemical Society, 2024) Gil Bravo, Antonio; Sancho Sanz, Iris; Korili, Sophia A.; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
    In recent years, there has been a surge of interest in transforming biomass into fuel, driven by its potential as the only realistic renewable carbon resource. Several conversion methods have been explored to achieve this, including gasification for producing synthesis gas, fast pyrolysis or hydrothermal liquefaction for obtaining bio-oils, and hydrolysis for generating aqueous sugars. Bio-oils offer environmental benefits due to their lower CO2 emissions, but their direct use as fuels is hindered by limitations such as thermal instability, high viscosity and acidity, and low calorific value. Consequently, advancements in treatment methods are necessary before bio-oils can be used as direct fuels. This review focuses on the catalytic hydrotreatment of bio-oils, which has been shown to be an effective approach for the removal of heteroatoms at moderate temperatures (between 300 and 450 °C) but at high pressures (up to 20 MPa). Oxygenated compounds are transformed into H2O, and N and S are transformed into NH3 and H2S, respectively. The analysis examines how process temperature, residence time, hydrogen pressure, solvent selection, and type of catalyst influence the properties of the improved bio-oil. Mo/W sulfide-supported catalysts have been traditionally used as active phases in hydrotreatment processes, as the presence of S limits catalyst deactivation, while the presence of Ni or Co as promoters enhances hydrogenation reactions. New research trends are exploring alternative catalyst formulations, such as metal phosphides, carbides, nitrides, and mesoporous materials as supports with controlled acid-basic properties.
  • PublicationOpen Access
    Who do I look like more, mom or dad? an exploratory survey about primary students' ideas about heredity
    (2024-06-21) Zudaire Ripa, María Isabel; Ayuso Fernández, Gabriel Enrique; Napal Fraile, María; Uriz Doray, Irantzu; Ciencias; Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
    Unlike in other countries, heredity and genetics appear first in Spanish science standards in secondary levels. However, some researchers have suggested the need of progressively introducing some basic genetic ideas already from primary education levels. In this context of no formal instruction in early stages, the objectives of our work were to characterize the incipient heredity model of primary school pupils and to evaluate its progression, to identify the most appropriate time to introduce these ideas. We designed a 12-item questionnaire referred to two constructs: (1) the difference between biologically inherited and environmental acquired traits and (2) the mechanism of inheritance. 535 primary school pupils (6¿12 years; grades 1¿6) took part in the study. In addition, 1¿2 pupils per class were interviewed, totalling 30 interviewees. The results showed that pupils clearly identified physical resemblance as inheritable but had more difficulties in assessing physiological traits. Most pupils (84%) correctly identified that accidentally acquired traits were not transmitted to the descendance. However, only 32,2% of them use terms related to inheritance (77,1% of them in G4 ¿ G6). Regarding the mechanism of inheritance, the idea that siblings express traits of both parents becomes more prevalent from grade 3, even suggesting the appearance of new traits or the mixture of previous ones. Older pupils accepted that a trait could skip a generation, although most of them were unable to explain the mechanism, that involves the idea of dominance/ recessiveness. These results allow identifying key leverage points for constructing the inheritance model at Primary levels.
  • PublicationEmbargo
    A sustainable approach for the valorization of lignocellulosic biomass in active photo- and electrocatalyst carbon dots
    (Springer, 2024) Jorge, Herculys Bernardo; Gier Della-Rocca, Daniela; Herrera, Elisa Gabriela; Rodríguez-Castellón, Enrique; Gil Bravo, Antonio; De Amorim, Suélen Maria; Winiarski, Joao Paulo; Da Cruz Vieira, Iolanda; Peralta Muniz Moreira, Regina de Fatima; Algarra González, Manuel; Peralta, Roselyn Aparecida; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    The recovery or degradation of organic wastes in the circular economy concept continues to be environmental protection challenges. In this study, we proposed a metal catalyst free production of useful non-doped (CDs) and nitrogen doped carbon dots (N-CDs) nanoparticles, generated from a greener hydrothermal top-down method, using paper scraps solid organic wastes from the pulp and paper industry. Both materials were fully characterized. At the same time, these high-added value materials were used as catalysts for the photocatalytic degradation of pollutants and for generating hydrogen through hydrogen evolution reaction (HER). The morphological study revealed the presence of nanoparticles with a higher carbon content than the raw biomass, from 13 to 51 wt% as assessed by X-ray photoelectron spectroscopy (XPS), ranging in size from 4.4 to 6.8 nm. The ability of these materials to catalyze the photodegradation of 4-nitrophenol has been tentatively investigated. The N-CDs proved to be more active than undoped-CDs to degrade 4-nitrophenol due to the smaller bandgap and more active sites available which will also accept the transferred electrons for H2 generation or 4-nitrophenol reduction.
  • PublicationOpen Access
    On the application of an in situ catalyst characterization system (ICCS) and a mass spectrometer detector as powerful techniques for the characterization of catalysts
    (MDPI, 2023) Yunes, Simón; Kenvin Jeffrey; Gil Bravo, Antonio; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    The in situ characterization of catalysts provides important information on the catalyst and the understanding of its catalytic performance and selectivity for a specific reaction. Temperature programmed analyses (TPX) techniques for catalyst characterization reveal the role of the support on the stabilization and dispersion of the active sites. However, these can be altered at high temperatures since sintering of active species can occur as well as possible carbon deposition which hinders the active species and deactivates the catalyst. The in situ characterization of the spent catalyst, however, may expose the causes of catalyst deactivation. For example, a simple temperature programmed oxidation (TPO) analysis on the spent catalyst may produce CO and CO2 via a reaction with O2 at high temperatures and this is a strong indication that deactivation may be due to the deposition of carbon. Other TPX techniques such as temperature programmed reduction (TPR) and pulse chemisorption are also valuable techniques when they are applied in situ to the fresh catalyst and then to the catalyst upon deactivation. In this work, two Ni supported catalysts were considered as examples to elucidate the importance of these techniques in the characterization study of catalysts applied to the reaction of hydrogenation of CO2.
  • PublicationOpen Access
    High power illumination system for uniform, isotropic and real time controlled irradiance in photoactivated processes research
    (Elsevier, 2024) Sáenz Gamasa, Carlos; Hernández Salueña, Begoña; Sanz Carrillo, Diego; Pellejero, Ismael; Gandía Pascual, Luis; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    In the study of photocatalytic and photoactivated processes and devices a tight control on the illumination conditions is mandatory. The practical challenges in the determination of the necessary photonic quantities pose serious difficulties in the characterization of catalytic performance and reactor designs and configurations, compromising an effective comparison between different experiments. To overcome these limitations, we have designed and constructed a new illumination system based in the concept of the integrating sphere (IS). The system provides uniform and isotropic illumination on the sample, either in batch or continuous flow modes, being these characteristics independent of the sample geometry. It allows direct, non-contact and real time determination of the photonic quantities as well as versatile control on the irradiance values and its spectral characteristics. It can be also scaled up to admit samples of different sizes without affecting its operational behaviour. The performance of the IS system has been determined in comparison with a second illumination system, mounted on an optical bench, that provides quasi-parallel beam (QPB) nearly uniform illumination in tightly controlled conditions. System performance is studied using three sample geometries: a standard quartz cuvette, a thin straight tube and a microreactor by means of potassium ferrioxalate actinometry. Results indicate that the illumination geometry and the angular distribution of the incoming light greatly affect the absorption at the sample. The sample light absorption efficiency can be obtained with statistical uncertainties of about 3% and in very good agreement with theoretical estimations.
  • PublicationOpen Access
    Life cycle assessment of wheat straw pyrolysis with volatile fractions chemical looping combustion
    (MDPI, 2024) Mendiara, Teresa; Navajas León, Alberto; Abad, Alberto; Pröll, Tobias; Munárriz, M.; Gandía Pascual, Luis; García-Labiano, Francisco; de Diego, Luis F.; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    Among the approaches to facilitating negative CO2 emissions is biochar production. Biochar is generated in the pyrolysis of certain biomasses. In the pyrolysis process, carbon in the biomass is turned into a solid, porous, carbon-rich, and stable material that can be captured from the soil after a period of from a few decades to several centuries. In addition to this long-term carbon sequestration role, biochar is also beneficial for soil performance as it helps to restore soil fertility and improves the retention and diffusion of water and nutrients. This work presents a Life Cycle Assessment of different pyrolysis approaches for biochar production. Biomass pyrolysis is performed in a fixed-bed reactor, which operates at a mild temperature (550 °C). Biochar is obtained as solid product of the pyrolysis, but there are also liquid (bio-oil) and gaseous products (syngas). The pyrolysis gas is partly used to fulfil the energy demand of the pyrolysis process, which is highly endothermic. In the conventional approach, CO2 is produced during the combustion of syngas and emitted to the atmosphere. Another approach to facilitate CO2 capture and thus obtain more negative CO2 emissions in the pyrolysis process is burning syngas and bio-oil in a Chemical Looping Combustion unit. Life Cycle Assessment was performed of these approaches toward biomass pyrolysis to evaluate their environmental impact. The Chemical Looping Combustion approach significantly reduced the values of 7 of the 16 environmental impact indicators studied, along with the Global Warming Potential among them, it slightly increased the value of one indicator related to the use of fossil resources, and it maintained the values of the remaining 8 indicators. Environmental impact reduction occurs due to the avoidance of CO2 and NOx emissions with Chemical Looping Combustion. The CO2 balances of the different pyrolysis approaches with Chemical Looping Combustion configurations were compared with a base case, which constituted the direct combustion of wheat straw to obtain thermal energy. Direct biomass combustion for the production of 17.1 MJ of thermal energy had CO2 positive emissions of 0.165 kg. If the gaseous fraction was burned by Chemical Looping Combustion, CO2 was captured and the emissions became increasingly negative, until a value of -3.30 kg/17.1 MJ was generated. If bio-oil was also burned by this technology, the negative trend of CO2 emissions continued, until they reached a value of -3.66 kg.
  • PublicationOpen Access
    Effects of long-term sewage sludge addition to a calcareous soil on soil organic C fractions and soil functions
    (Elsevier, 2024) Simoes da Mota, Ana Claudia; Barré, Pierre; Baudin, François; Poch, Rosa María; Bruni, Elisa; Antón Sobejano, Rodrigo; Enrique Martín, Alberto; Virto Quecedo, Íñigo; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Soil organic matter (SOM) is a recognized carbon reservoir and paramount in soil functioning and agrosystems productivity. Different management strategies have been established to enhance SOM in arable soils, and one is the application of exogenous organic matter (EOM). Despite significant efforts in recent years, the consequences of EOM addition on increasing soil organic C (SOC) storage and stability in different pedoclimatic contexts remain incompletely understood. In this study, we evaluated the effect of long-term (28 y) sewage sludge (SS) addition to a calcareous soil supporting rainfed extensive crops in a Mediterranean sub-humid area in terms of SOC stabilization and distribution among functional fractions. To that end, we studied total SOM storage and soil fractions in a long-term experiment comparing 4 different doses of SS with mineral fertilization and no-fertilization controls. We compared the concentration, storage and distribution of C using two different fractionation methods (particulate vs. mineral-associated, defined by granulodensimetric fractionation, and active C vs. stable C defined by Rock-Eval® thermal analysis coupled to the machine learning PARTYsoc v2.0 model) on the tilled layer (0–30 cm). Three soil functioning indicators (crops yield, soil microbial biomass C and aggregate stability) were also quantified. We found that SS application, which slightly increased SOC concentration when SS was added, resulted in a net SOC stock gain only with the highest dose used (80 tons/ha), compared to mineral fertilization, suggesting that most of the C added was mineralized. An uneven response of soil fractions was however detected. The coarsest heavy physical fractions > 250 μm and 50–250 μm in size were the most enriched in their C concentration with SS addition, whereas SOC was mostly accumulated as mineral-associated C in the silt-size (2–50 μm) and the 50–250 μm fractions. Regarding thermal fractionation, SS treatments showed C gains between 57 % and 35 % in the active C pool, compared to mineral fertilization. This can be explained considering that the accumulated SOM in mineral-associated fractions corresponded to mean-residence times in the order of 20–40 years. The consequences on soil functioning indicators were not directly related to the amount of SOC stored in the soil, as the highest SOC gains corresponded to the highest dose, but not the highest yields, and some negative correlations were observed between SOC fractions and soil structural stability and microbial biomass. This can be related to some deleterious effects of excessive SS application reducing yields, the soil biological activity and soil structure, and represents an example of the need to decouple the assessment of soil health from that of SOC storage for certain soil management practices. The overall evaluation of the net consequences of long-term SS application indicated that low doses (10 tons/ha) seem a better choice, as they resulted in the highest efficiency in C incorporation, and in a slightly greater increase in SOC concentration than intermediate doses, and equal yields than mineral fertilization, but did not have the negative effects observed in soil functioning with higher doses.
  • PublicationOpen Access
    Determination of hazardous vapors from the thermal decomposition of organochlorinated silica xerogels with adsorptive properties
    (Elsevier, 2024) Rosales Reina, María Beatriz; Cruz Quesada, Guillermo; Pujol, Pablo; Reinoso, Santiago; Elosúa Aguado, César; Arzamendi Manterola, María Cruz; López Ramón, María Victoria; Garrido Segovia, Julián José; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
    The incorporation of organic groups into sol-gel silica materials is known to have a noticeable impact on the properties and structure of the resulting xerogels due to the combination of the properties inherent to the organic fragments (functionality and flexibility) with the mechanical and structural stability of the inorganic matrix. However, the reduction of the inorganic content in the materials could be detrimental to their thermal stability properties, limiting the range of their potential applications. Therefore, this work aims to evaluate the thermal stability of hybrid inorganic-organic silica xerogels prepared from mixtures of tetraethoxysilane and organochlorinated triethoxysilane precursors. To this end, a series of four materials with a molar percentage of organochlorinated precursor fixed at 10%, but differing in the type of organic group (chloroalkyls varying in the alkyl-chain length and chlorophenyl), has been selected as model case study. The gases and vapors released during the thermal decomposition of the samples under N2 atmosphere have been analyzed and their components determined and quantified using a thermogravimetric analyzer coupled to a Fourier-transform infrared spectrophotometer and to a gas chromatography-mass spectrometry unit. These analyses have allowed to identify up to three different thermal events for the pyrolysis of the organochlorinated xerogel materials and to elucidate the reaction pathways associated with such processes. These mechanisms have been found to be strongly dependent on the specific nature of the organic group.
  • PublicationOpen Access
    Crop grey water footprints in China: the impact of pesticides on water pollution
    (Elsevier, 2024) Yi, J.; Gerbens-Leenes, Winnie; Martínez Aldaya, Maite; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Agricultural water pollution is a significant challenge in China, a rapidly growing economy with a large agricultural sector. The grey water footprint (WF) is a tool for evaluating freshwater pollution. It expresses pollution in volumetric units identifying the pollutant that theoretically needs most water to be diluted to accepted water quality standards. Previous agricultural grey WF studies focused on nitrogen (N) and phosphorus (P), some studies included pesticides. This study assesses grey WFs based on N, P and 1513 pesticide combinations for twelve main crops and two crop categories in 31 Chinese provinces. Grey WFs, including the pesticide component, are far larger than estimated before, dominating total agricultural WFs (green, blue, and grey). The total grey WF of Chinese agriculture (4,900 109 m3 year−1) is determined by pesticides, while grey WFs related to N and P are 450 and 1,500 109 m3 year−1, differences of a factor of eleven and three respectively. The provinces Heilongjiang, Inner Mongolia, Hebei, Henan, and Shandong are hotspots contributing 37 % to the total grey WF. A limited number of pesticides used for maize, vegetables, fruits and potato (Mancozeb a fungicide, Acetochlor a herbicide and Cypermethrin an insecticide) dominate total grey WFs, contributing 80 % to the total grey WF. Eliminating the most polluting pesticides per category and redistributing the remaining ones with a similar function but lower grey WFs reduces national water pollution from agriculture by 64 %. Only five crops, i.e. maize, potato, soybean, rice and wheat, and the two crop categories, vegetables and fruits, contribute 94 % to this reduction. Probably grey WFs could reduce even further with a second elimination and redistribution effort. This study is the first national grey WF assessment related to pesticides in agriculture. It offers valuable insights to farmers and policymakers to enhance water quality in China and beyond.
  • PublicationOpen Access
    Special issue: feature papers in Eng 2022
    (MDPI, 2023) Gil Bravo, Antonio; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    The aim of this second Eng Special Issue is to collect experimental and theoretical re-search relating to engineering science and technology. The general topics published in Eng are as follows: electrical, electronic and information engineering; chemical and materials engineering; energy engineering; mechanical and automotive engineering; industrial and manufacturing engineering; civil and structural engineering; aerospace engineering; biomedical engineering; geotechnical engineering and engineering geology; and ocean and environmental engineering. This editorial is an overview of the selected representative studies on these topics. This book contains 33 papers, including 2 Review papers and 1 Communication, published by several authors interested in new cutting-edge developments in the field of engineering. Recently, a subcategory of nanotechnology—nano- and microcontainers—has developed rapidly, with unexpected results. Nano- and microcontainers refer to hollow spherical structures in which the shells can be organic or inorganic. These containers can be filled with substances released when excited and can be used in corrosion healing, cancer therapy, cement healing, antifouling, etc. In the first review, the author summarizes the various innovative technologies that have beneficial effects on improving people’s lives [1].
  • PublicationOpen Access
    Crystal-to-crystal polymerisation of monosubstituted [PW11O39Cu(H2O)]5- Keggin-type anions
    (Royal Society of Chemistry, 2024) Ruiz Bilbao, Estíbaliz; Pache, Aroa; Barrenechea, Unai; Reinoso, Santiago; San Felices, Leire; Vivanco, Maria dM.; Lezama, Luis; Artetxe, Beñat; Gutiérrez Zorrilla, Juan M.; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    The reaction between neutral bis(picolinate)copper(ii) complexes and copper(ii)-monosubstituted Keggin-type phosphotungstate anions formed in situ leads to the formation of the hybrid [C(NH2)3]10[{PW11O39Cu(H2O)}2{Cu(pic)2}]·10H2O compound (1, pic = picolinate) in the presence of structure-directing guanidinium cations. Single-crystal X-ray diffraction studies demonstrate that 1 contains dimeric {PW11O39Cu(H2O)}2{Cu(pic)2} molecular species constituted by two Keggin-type anions linked by one {Cu(pic)2} octahedral complex through axial coordination to their terminal oxygen atoms. The extensive hydrogen-bonding network established by guanidium cations and Keggin clusters plays a key role in retaining the crystallinity of the system throughout dehydration to allow a single-crystal-to-single-crystal (SCSC) transformation into the anhydrous [C(NH2)3]10[{PW11O39Cu}2{Cu(pic)2}] (2a) at 170 °C. Structural modifications involve the re-orientation, shifting in ca. 1.5 Å and condensation of all the {PW11O39Cu} units to result in {PW11O39Cu}n chains in an unprecedented solid-state polymerisation. This phase transition also implies the cleavage of Cu-O bonds induced by the rotation and translation of Keggin-type anions, in such a way that hybrid dimeric units in 1 are dismantled and {Cu(pic)2} complexes become square planar. The irreversibility of the phase transition has been confirmed by combined thermal and diffractometric analyses, which evidence that the anhydrous phase adsorbs only one water molecule per cluster to become the [C(NH2)3]10[{PW11O39Cu}2{Cu(pic)2}]·2H2O (2h) hydrated derivative without any significant alteration in its cell parameters, nor in its crystalline structure. Phase transformations have been monitored by electron paramagnetic resonance spectroscopy.
  • PublicationOpen Access
    Changes in the soil inorganic carbon dynamics in the tilled layer of a semi-arid Mediterranean soil due to irrigation and a change in crop: uncertainties in the calculation of pedogenic carbonates
    (Elsevier, 2024) De Soto García, Isabel Sonsoles; Barré, Pierre; Zamanian, Kazem; Urmeneta Martín-Calero, Henar; Antón Sobejano, Rodrigo; Enrique Martín, Alberto; Virto Quecedo, Íñigo; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
    Soil inorganic carbon (SIC) accounts for more than one-third of the total soil carbon pool, but the effect of agricultural management on carbonates dynamics in Mediterranean semi-arid calcareous soils has largely been ignored and remains unclear. However, SIC plays a key role in physical, chemical and, biological properties of soils, which in turn can affect plant growth and productivity. Based on a 7-year field experiment in a paired irrigated and non-irrigated trial, with two different crops (maize and wheat), we investigated the effects of the land use change (from non-irrigated wheat to irrigated maize) on the SIC dynamics in the topsoil (0¿30 cm) of a carbonate-rich soil in Navarre, northern Spain. The results obtained using the accepted equation for determining carbonate type showed that during the 7-year study period, irrigation application and the crop change modified the carbonate typology (lithogenic and pedogenic) in a very short period, without affecting the total SIC content. The main drivers of pedogenic carbonate formation in this case appear to be the water volume and the type of organic matter entering the soil (from C3 plants or C4 plants). However, the equation seems to be strongly dependent on the type of soil organic carbon, which can introduce uncertainties when used to determine the proportion of pedogenic carbonates in soils experiencing a crop change from C3 to C4 plants.
  • PublicationOpen Access
    Life cycle assessment in higher education: design and implementation of a teaching sequence activity
    (MDPI, 2024) Navajas León, Alberto; Echarri San Martín, Itsaso Andrea; Gandía Pascual, Luis; Pozuelo, Jorge; Cascarosa, Esther; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    The latest studies show that to achieve the Sustainable Development Goals on education, there must be a focus on adequately training higher education students. In this work, we present a study about the Life Cycle Analysis of knowledge of products and processes of engineering students. This aspect is very relevant in engineering education since it has direct implications on sustainability. The first step was to identify what the learning problems were, and taking them into account, a specific teaching sequence was designed and implemented over three academic years. Two activities, on an increasing level of complexity, of the application of Life Cycle Assessment are shown in this paper. The first one is the Life Cycle Analysis comparison between two steel and polypropylene pieces. The second one is the Life Cycle Analysis comparison between three different ends of life of a polypropylene piece: mechanical recycling, incineration, and landfill. Data on the evolution of students' marks while solving a ¿one step more difficult project¿ throughout these courses have been collected. The results show a generalized learning by the students about Life Cycle Analysis.
  • PublicationOpen Access
    Environmental conditions play a key role in controlling the composition and diversity of Colombian biocrust microbiomes
    (Frontiers, 2024) Giraldo-Silva, Ana; Masiello, Caroline A.; Ciencias; Zientziak; Institute for Multidisciplinary Research in Applied Biology - IMAB
    Drylands soils worldwide are naturally colonized by microbial communities known as biocrusts. These soil microbiomes render important ecosystem services associated with soil fertility, water holding capacity, and stability to the areas they cover. Because of the importance of biocrusts in the global cycling of nutrients, there is a growing interest in describing the many microbial configurations these communities display worldwide. However, comprehensive 16S rRNA genes surveys of biocrust communities do not exist for much of the planet: for example, in the continents of South America and the northern part of Africa. The absence of a global understanding of biocrust biodiversity has lead us to assign a general importance to community members that may, in fact, be regional. Here we report for the first time the presence of biocrusts in Colombia (South America) through 16S rRNA genes surveys across an arid, a semi-arid and a dry subtropical region within the country. Our results constitute the first glance of the Bacterial/Archaeal communities associated with South American biocrust microbiomes. Communities where cyanobacteria other than Microcoleus vaginatus prevail, despite the latter being considered a key species elsewhere, illustrate differentiable results in these surveys. We also find that the coastal biocrust communities in Colombia include halo-tolerant and halophilic species, and that niche preference of some nitrogen fixing organisms deviate from previously described global trends. In addition, we identified a high proportion (ranging from 5 to 70%, in average) of cyanobacterial sequences that did not match any formally described cyanobacterial species. Our investigation of Colombian biocrusts points to highly diverse communities with climatic regions controlling taxonomic configurations. They also highlight an extensive local diversity to be discovered which is central to better design management and restoration strategies for drylands soils currently undergoing disturbances due to land use and global warming. Finally, this field study highlights the need for an improved mechanistic understanding of the response of key biocrust community members to changes in moisture and temperature.
  • PublicationOpen Access
    Water footprint in rainfed summer and winter crops: the role of soil moisture
    (Elsevier, 2024) Olivera Rodríguez, Paula; Holzman, Mauro Ezequiel; Martínez Aldaya, Maite; Rivas, Raúl Eduardo; Ciencias; Zientziak; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Argentina is one of the main producers and exporters of grains and oilseeds, ranking third in soybean exports and fourth in barley ones. The 90% of this production occurs within the Argentine Pampas region (APR) under rainfed conditions, but its water consumption and pollution has not been studied in depth. Likewise, the link between soil moisture (SM) and Water Footprint (WF) generation is poorly studied at the global level. And yet, SM is a critical factor for the development of rainfed crops. This study aims to evaluate, at plot scale, the role of SM in the generation of the green (WFgreen) and grey (WFgrey) (WF). Additionally, it estimates the WF for rainfed barley and soybean crops in the Southeast of APR, where there are no reference values. Yields, water consumption and nitrogen (N) pollution load were estimated for different campaigns. Field data (weather, crop and production management) recorded in the study plots were used. Results indicated an average WFgreen of 1236 m3/t for soybeans and a WFgreen of 349 m3/t and WFgrey of 547 m3/t for barley. The study highlights the critical role of SM in both WF sub-indicators. Soil water availability, based on the evaporative fraction during critical growth stages, influenced yields and final WFgreen volumes. In addition, there was an effect on N uptake by crops. In the driest barley campaign, WFgrey increased by 234%. Insufficient SM restricted nutrient uptake, reducing yields and increasing N with the potential to leach or runoff. Consequently, it is suggested to adjust the WFgrey methodology incorporating SM fluctuations and unaccounted N losses. The study contributes to understand the WF drivers and highlights the need to assess them accurately. In particular, it aims to reduce the gaps surrounding the water consumption of rainfed crops, thereby supporting resource conservation and grain provisioning efforts.
  • PublicationOpen Access
    Immobilization of polyoxometalates on tailored polymeric surfaces
    (MDPI, 2018) Aguado-Ureta, Saioa; Rodríguez-Hernández, Juan; Campo, Adolfo del; Pérez-Álvarez, Leyre; Ruiz-Rubio, Leire; Vilas, José Luis; Artetxe, Beñat; Reinoso, Santiago; Gutiérrez Zorrilla, Juan M.; Ciencias; Zientziak
    Herein we describe the preparation of hybrid polymer–inorganic interfaces by the immobilization of polyoxometalate nanoclusters on functionalized polymer surfaces. The polymeric surfaces were made of polystyrene-b-poly(acrylic acid)/polystyrene (PS-b-PAA/PS) blends by spin coating on a silicon wafer. The functionalization of the polymer film was obtained by interfacial migration of the amphiphilic block copolymer toward the interface upon water vapor annealing. The carboxylic acid functional groups contained in the PAA block were then employed to anchor the [LnIII(α-SiW11O39)]5− polyoxometalates (Ln: Ce, Er). This purpose was achieved by immersing the films in aqueous solutions of the in situ-formed inorganic nanoclusters. X-ray photoelectron and confocal Raman spectroscopies, together with atomic force microscopy, confirmed the immobilization of the inorganic species at the interface.
  • PublicationOpen Access
    The effects of halogen substituents on the catalytic oxidation of benzylalcohols in the presence of dinuclear oxidovanadium(IV) complex
    (Elsevier, 2017) Bikas, Rahman; Shahmoradi, Elaheh; Noshiranzadeh, Nader; Emami, Marzieh; Reinoso, Santiago; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2
    A new dinuclear complex of oxidovanadium(IV), namely [(VO)2(HL)(l-O)] (1), has been synthesized by the reaction of VO(acac)2 with the heptadentate N4O3-donor Schiff base ligand, 2-(5-Bromo-2-hydroxyphenyl)-1,3-bis(2-(5-bromo-2-hydroxybenzylideneamino)ethyl)imidazolidine (H3L). The complex has been characterized by elemental analysis, spectroscopic methods and single-crystal X-ray diffraction. The latter technique revealed that the vanadium ions have distorted octahedral geometry and are connected together by oxido and phenolic oxygen atoms. The bridging oxido ligand shares the equatorial positions of the two metal centers while the oxygen atom of the bridging phenol group connects the axial positions. The catalytic activity of this complex has been tested for the oxidation of some benzyl alcohol derivatives by using H2O2 as a green oxidant. In order to maximize the yields, the effects of various influential parameters in catalytic reactions such as the oxidant-to-substrate molar ratio, the temperature and the solvent, were studied. Moreover, the electronic and steric effects of halogen substituents on the phenyl group of the substrate were also explored by analyzing the oxidation of benzyl alcohol derivatives with F, Cl and Br atoms in the relative para-position (electronic effect), and of another set of substrates with a Cl substituent in relative ortho-, meta, and para-positions (steric effect). The results of these catalytic studies show that complex 1 catalyzes the oxidation of benzyl alcohol derivatives to the corresponding benzaldehydes with little amounts of the benzoic acid being detectable in the reaction mixture. Both the reaction conditions and the substituents on the phenyl group of the benzyl alcohols affect the selectivity and the activity of this catalytic system.
  • PublicationOpen Access
    Hydrogen gas-grilling in meat: impact on odor profile and contents of polycyclic aromatic hydrocarbons and volatile organic compounds
    (MDPI, 2024) Beriain Apesteguía, María José; Gómez Bastida, Inmaculada; García Murillo, Susana; Urroz Unzueta, José Carlos; Diéguez Elizondo, Pedro; Ibáñez Moya, Francisco C.; Ingeniería; Ingeniaritza; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Ciencias; Zientziak
    The effect of fuel (hydrogen vs. butane) on the formation of volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) was evaluated for grilled horse meat (very low-fat and low-fat) cooking vertically. Gas chromatography-mass spectrometry was used to analyze PAHs and VOCs. An electronic nose was used to evaluate the odor profile. Total high-molecular-weight PAHs ranged from 19.59 to 28.65 µg/kg with butane and from 1.83 to 1.61 µg/kg with hydrogen. Conversely, total low-molecular-weight PAHs went from 184.41 to 286.03 µg/kg with butane and from 36.88 to 41.63 µg/kg with hydrogen. Aldehydes and alkanes were the predominant family in a total of 59 VOCs. Hydrogen gas-grilling reduced significantly (p < 0.05) the generation of VOCs related to lipid oxidation. The odor profile was not modified significantly despite the change of PAHs and VOCs. The findings indicate that hydrogen is a viable alternative to butane for grilling horse meat. Hydrogen gas-grilling may be regarded as a safe cooking procedure of meat from a PAH contamination point and perhaps sustainable environmentally compared to a conventional technique. The present study provides the basis for the use of hydrogen gas in grilled meat.