Juan De La Cierva Research Articles

New Insights and Strategies for the Efficient Use of Conjugated Porous Polymers in Photoelectrochemical Solar Fuel Production

Solar energy conversion into fuels such as hydrogen through photoelectrochemical (PEC) cells is an attractive way to solve the problems present in the actual energetic system. (1) Despite the advances that have been made in this line, it is still necessary to develop new materials and cell configurations to take this technology to a higher scientific level. The application of organic polymers in PEC is a hot topic that continues to grow due to the promising optoelectronic properties of this class of semiconductors. Conjugated polymers exhibit advanced properties because of it particular conjugation that confers it a huge conductivity through the whole structure. (2) In particular, Conjugate Porous Polymers (CPP) offers a higher photostability and robustness that is fundamental for long term application, but their synthesis often leads to a large-particle powder, unsuitable for preparing thin films, key to preparing high-quality thin films, limiting its applicability in PEC.(3)In this work, we present two innovative strategies that allow the efficient use of these materials in photoelectrochemical cells. The first consists of a synthetic route through mini or ultra-mini emulsion synthesis that provides particles from 500 nm to 20 nm, adequate for thin film preparation. The second consists in the design of suitable monomers to be electropolymerised, obtaining high quality thin films and highly controlled thickness. These strategies allow the complete characterization of the optoelectronic properties of the CPPs, since the thin films obtained are of high quality and stable over time. In this way, several polymers have been prepared and the electronic structure was determined by a combination different techniques such as XPS, electrochemistry and UV-VIS spectroscopy, revealing the suitability to be used as photoelectrodes.The photoelectrochemical properties were analyses by means of linear sweep voltammetry, chronoamperometry, and Photopotential measurements suggesting its potentiality for solar energy conversion. In addition, attending o the conductivity type and electronic properties, both photoelectrodes and tandem cells have been designed by combining them with different materials such as TiO2. The formed hybrid photoelectrodes have been characterized by X-ray diffraction, SEM, EDX and AFM. A series of photoelectrochemical measurements have been performed in a three electrode cell configuration, using the hybrid materials as working electrodes. (4)Hybrid photoelectrodes present improved photovoltages and photocurrents compared to TiO2 and CPP alone, confirming adequate light absorption and charge transfer between them. Besides, Electrochemical Impedance Spectroscopy (EIS) was performed to confirm the improved charge transfer observed when illuminating the hybrid photoelectrodes. Furthermore, the designed tandem cells were connected to a gas chromatograph and the hydrogen evolution was confirmed and quantified. Keywords: Photoelectrochemistry, Solar fuels, Organic materials, Conjugate Porous Polymers, References M. Grätzel, Photoelectrochemical cells. Nature. 414, 338–344 (2001).M. Liras, M. Barawi, V. A. de la P. O’Shea. Chem. Soc. Rev. 48, 5454–5487 (2019).M. Barawi, L. Collado, M. Gomez-Mendoza, F. E. Oropeza, M. Liras, V. A. de la P. O’Shea, C. Adv. Energy Mater. 18, 2101530 (2021).M. Barawi, E. Alfonso-González, C.G. López-Calixto, A. García, A. García-Sánchez, I. J. Villar-García, M. Liras, V.A. de la Peña O'Shea. Small, 18, 37. 2201351 (2022). Acknowledgements This work was supported by the Spanish national project NovaCO2 (PID2020-118593RB-C22) and ERC POC (NanoCPP). M.B thanks the Juan de la Cierva Incorporación grant (IJC2019 – 042430 –I).

On the Hardness of Learning from Censored and Nonstationary Demand

We consider a repeated newsvendor problem in which the inventory manager has no prior information about the demand and can access only censored/sales data. In analogy to multiarmed bandit problems, the manager needs to simultaneously “explore” and “exploit” with inventory decisions in order to minimize the cumulative cost. Our goal is to understand the hardness of the problem disentangled from any probabilistic assumptions on the demand sequence—importantly, independence or time stationarity—and, correspondingly, to develop policies that perform well with respect to the regret criterion. We design a cost estimator that is tailored to the special structure of the censoring problem, and we show that, if coupled with the classic exponentially weighted forecaster, it achieves optimal scaling of the expected regret (up to logarithmic factors) with respect to both the number of time periods and available actions. This result also leads to two important insights: the benefit from “information stalking” as well as the cost of censoring are both negligible, at least in terms of the regret. We demonstrate the flexibility of our technique by combining it with the fixed share forecaster to provide strong guarantees in terms of tracking regret, a powerful notion of regret that uses a large class of time-varying action sequences as benchmark. Numerical experiments suggest that the resulting policy outperforms existing policies (that are tailored to or facilitated by time stationarity) on nonstationary demand models with time-varying noise, trend, and seasonality components. Finally, we consider the “combinatorial” version of the repeated newsvendor problem, that is, single-warehouse, multiretailer inventory management of a perishable product. We extend the proposed approach so that, again, it achieves near-optimal performance in terms of the regret. Funding: G. Lugosi was supported by the Spanish Ministry of Economy, Industry and Competitiveness [Grant MTM2015-67304-P (AEI/FEDER, UE)]. M. G. Markakis was supported by the Spanish Ministry of Economy and Competitiveness [Grant ECO2016-75905-R (AEI/FEDER, UE)] and a Juan de la Cierva fellowship as well as the Spanish Ministry of Science and Innovation through a Ramón y Cajal fellowship. G. Neu was supported by the UPFellows Fellowship (Marie Curie COFUND program) [Grant 600387]. Supplemental Material: The e-companion is available at https://doi.org/10.1287/ijoo.2022.0017 .

Decomposition Strategies for Vehicle Routing Heuristics

Decomposition techniques are an important component of modern heuristics for large instances of vehicle routing problems. The current literature lacks a characterization of decomposition strategies and a systematic investigation of their impact when integrated into state-of-the-art heuristics. This paper fills this gap: We discuss the main characteristics of decomposition techniques in vehicle routing heuristics, highlight their strengths and weaknesses, and derive a set of desirable properties. Through an extensive numerical campaign, we investigate the impact of decompositions within two algorithms for the capacitated vehicle routing problem: the Adaptive Large Neighborhood Search of Pisinger and Ropke (2007 ) and the Hybrid Genetic Search of Vidal et al. (2012 ). We evaluate the quality of popular decomposition techniques from the literature and propose new strategies. We find that route-based decomposition methods, which define subproblems by means of the customers contained in selected subsets of the routes of a given solution, generally appear superior to path-based methods, which merge groups of customers to obtain smaller subproblems. The newly proposed decomposition barycenter clustering achieves the overall best performance and leads to significant gains compared with using the algorithms without decomposition. History: Erwin Pesch, Area Editor for Heuristic Search and Approximation Algorithms. Funding: This work was supported by the U.S. Air Force [Grant FA9550-17-1-0234], the Ministerio de Ciencia e Innovación (Juan de la Cierva Formación), H2020 Marie Skłodowska-Curie Actions [Grant 945380], the Ministero dell’Università e della Ricerca [Grant 2015JJLC3E_002], the Conselho Nacional de Desenvolvimento Científico e Tecnológico [Grant 308528/2018-2], and the Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro [Grant E-26/202.790/2019]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information ( https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2023.1288 ) as well as from the IJOC GitHub software repository ( https://github.com/INFORMSJoC/2022.0048 ) at ( http://dx.doi.org/10.5281/zenodo.7613129 ).

Artificial anatomy.

Artificial anatomy.

Sequential Bidding for Merging in Algorithmic Traffic

Problem definition: We consider the problem of resolving ad hoc unpredictable congestion in environments where customers have private time valuations. We investigate the design of fair, efficient, budget-balanced, and implementable bidding mechanisms for observable queues. Academic/practical relevance: Our primary motivation comes from merging in algorithmic traffic, i.e., a driver wishing to merge in a relatively dense platoon of vehicles in a coordinated and efficient way, using intervehicle communication and micropayments, akin to an arriving customer trading for position in a single-server observable queue. Methodology: We analyze the performance of a mechanism where the queue joiner makes sequential take-it-or-leave-it bids from tail to head (T2H) of a platoon, with the condition that the vehicle can advance to the next position only if it wins the bid. This mechanism is designed so that it is implementable, balances the budget, and imposes no negative externalities. Results: We compared this mechanism with head to tail (H2T) bidding, which favors the merging driver but potentially causes uncompensated externalities. Assuming i.i.d. time valuations, we obtain the optimal bids, value functions, and expected social welfare in closed form in both mechanisms. Moreover, if the time valuation of the merging driver is not high, we show that the expected social welfare of T2H is close to a partial information social optimum and that the expected social welfare of H2T is lower than that of T2H as long as the platoon is not too short. Managerial implications: Our findings suggest that mechanisms based on sequential take-it-or-leave-it bids from T2H of an observable queue have good social welfare performance, even if the corresponding bids are not chosen optimally, as long as the time valuation of the arriving customer is not high. Nevertheless, the tension between individual incentives and social welfare seems hard to resolve, highlighting the role of platforms to enforce the cooperation of involved parties. Funding: This work was supported by the Spanish Ministry of Economy and Competitiveness [Grants ECO2013-41131-R and ECO2016-75905-R (AEI/FEDER, UE)]. M.G. Markakis was also supported by the Spanish Ministry of Science and Innovation [the Juan de la Cierva fellowship and the Ramón y Cajal fellowship]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.1144 .

Review and synthesis of stress intensity factor (SIF) solutions for elliptical surface cracks in bolts under tension loading: A Tribute to Juan de la Cierva

This paper presents stress intensity factor (SIF or K) solutions for a semi-elliptical surface crack in a bolt subjected to tension. Solutions were numerically computed by a 3D finite element method (FEM) with quarter-point singular isoparametric elements along the crack line. The SIF was calculated through the stiffness derivative method, by using a virtual crack extension technique to compute the energy release rate. Solutions are compared in the matter of stress intensity values at the center of the crack front and at the external surface of the bolt, and a wide range of crack aspect ratios and relative crack depths are studied, in order to provide the engineer with solutions applicable to different real situations in fracture mechanics or damage tolerance analyses such as static or cyclic (fatigue) loading, environmentally assisted cracking or corrosion-fatigue.In Memoriam: The paper is dedicated to the memory of the prominent Spanish engineer Juan de la Cierva, inventor of “autogiro”.

Toward the Recycling of Low-GWP Hydrofluorocarbon/Hydrofluoroolefin Refrigerant Mixtures Using Composite Ionic Liquid–Polymer Membranes

Authors fully acknowledge the financial support received from Project KET4F-Gas-SOE2/P1/P0823, which is cofinanced by the European Regional Development Fund within the framework of Interreg Sudoe Programme, and project PID2019-105827RB-I00—Agencia Estatal de Investigacion, Spain. F.P. acknowledges the postdoctoral fellowship (FJCI-2017-32884 Juan de la Cierva Formacion) awarded by the Spanish Ministry of Science, Innovation and Universities.

Urban sprawl into Natura 2000 network over Europe.

Urban growth is a major threat to biodiversity conservation at the global scale. Its impacts are expected to be especially detrimental when it sprawls into the landscape and reaches sites of high conservation value due to the species and ecosystems they host, such as protected areas. I analyzed the degree of urbanization (i.e., urban cover and growth rate) from 2006 to 2015 in protected sites in the Natura 2000 network, which, according to the Habitats and Birds Directives, harbor species and habitats of high conservation concern in Europe. I used data on the degree of land imperviousness from COPERNICUS to calculate and compare urban covers and growth rates inside and outside Natura 2000. I also analyzed the relationships of urban cover and growth rates with a set of characteristics of Natura sites. Urban cover inside Natura 2000 was 10 times lower than outside (0.4% vs. 4%) throughout the European Union. However, the rates of urban growth were slightly higher inside than outside Natura 2000 (4.8% vs. 3.9%), which indicates an incipient urban sprawl inside the network. In general, Natura sites affected most by urbanization were those surrounded by densely populated areas (i.e., urban clusters) that had a low number of species or habitats of conservation concern, albeit some member states had high urban cover or growth rate or both in protected sites with a large number of species or habitats of high conservation value. Small Natura sites had more urban cover than large sites, but urban growth rates were highest in large Natura sites. Natura 2000 is protected against urbanization to some extent, but there is room for improvement. Member states must enact stricter legal protection and control law enforcement to halt urban sprawl into protected areas under the greatest pressure from urban sprawl (i.e., close to urban clusters). Such actions are particularly needed in Natura sites with high urban cover and growth rates and areas where urbanization is affecting small Natura sites of high conservation value, which are especially vulnerable and concentrated in the Mediterranean region.

New macaque fossil remains from Morocco

This work has been funded by Palarq Foundation, Spanish Ministry of Culture and Sport (42-T002018042853 and 170-T002019038589), Direction of Cultural Heritage (Ministry of Culture and Communication, Morocco), Faculty of Sciences (Mohamed 1r University of Oujda, Morocco), INSAP (Institut National des Sciences de l’Archeologie et du Patrimoine), Agencia Estatal de Investigacion (Spanish Ministry of Science, Innovation and Universities: CGL2016-76431-P, CGL2016-80975-P, CGL2016-80000-P, CGL2017-82654-P, PGC2018-095489-B-I00, and PGC2018-093925-B-C31, AEI/FEDER-UE), and Research Group Support of the Generalitat de Catalunya (2017 SGR 116, 2017 SGR836, and 2017 SGR 859). The research by D.M.A., R.S-R, M.G.C., P.S., C.L., and E.D. is funded by CERCA Programme/Generalitat de Catalunya. A.M.A and M.F. are beneficiaries of a fellowship from the Erasmus Mundus Program to do the Master in Quaternary and Prehistory at the Universitat Rovia i Virgili (Tarragona, Spain). A.R.-H. is the beneficiary of a postdoctoral scholarship from the MICINN, Subprograma Juan de la Cierva (IJC-037447-I), and member of theconsolidated research group 2017 SGR 1040 of the Generalitat de Catalunya. The Institut Catala de Paleoecologia Humana i Evolucio Social (IPHES-CERCA) has received financial support from the Spanish Ministry of Science and Innovation through the ‘Maria de Maeztu’ program for Units of Excellence (CEX2019-000945-M).

Heart and lung aquaporins play a major role in severity of heart failure with preserved ejection fraction in mice and differs between comorbidities

Abstract Introduction Heart failure (HF) is a major public health problem worldwide. To date, HF with preserved ejection fraction (EF, HFpEF) represents half of all HF patients and its prevalence is increasing. HFpEF is associated with multiple comorbidities, including diabetes mellitus, pulmonary and systemic hypertension and obesity, mainly in elderly population. Accurately phenotyping HFpEF is crucial for the development of new therapies, appropriate patient stratification and the implementation of a personalised medicine. Cardiac and pulmonary remodelling play a major role in HFpEF severity but the specific mechanisms underlying cardiac failure and lung congestion, the last stage in HFpEF, in each comorbidity are incompletely understood, precluding the development of effective therapies. Aquaporins (AQP) are membrane proteins serving as water channels across the plasma membrane and control intra- and extracellular fluid volume and prompt to tissue oedema in many organs. However, its specific contribution in HFpEF has not been explored. Purpose We aimed to identify cardiac and pulmonary molecular changes associated to dysfunction and oedema in HFpEF, specific for each comorbidity. Methods A total of 48 C57BL/6 mice 10 weeks old were randomised to the following groups: control (Ctl; n=9), type I diabetes (Db; n=9), chronic hypoxia (PAH; n=10), obesity (Ob; n=10) and systemic arterial hypertension (SAH; n=10). Mice were followed for up to 2.5 years by echocardiography and lung ultrasound until they developed pulmonary oedema (HF) or died naturally. Lungs and heart were extracted and changes were determined by proteomic, immunohistochemistry and qRT-PCR. Results Diastolic dysfunction was observed in all comorbidities and above 50% of those mice developed HF. Db presented the highest ratio in developing HF. Db also showed the earliest mortality (47 weeks), whereas PAH, Ob and SAH mice survived for 82, 92 and 99 weeks, respectively (p<0.001 vs Ctl). A common finding in all groups was the development of different degrees o perivascular fibrosis. Db mice, the HFpEF severest group, showed an increase in pulmonary AQP1 and 5 (p<0.05 and p<0.001, respectively, vs Ctl). Upregulation of AQPs correlated with increased ventricular filling pressures (E/E', r2=07). Cardiac AQP4 was also markedly elevated in Db mice in left and right ventricle (p<0.001 and p=0.01, respectively, vs Ctl). Conclusion Increased AQPs in the lung is associated with a more aggressive development of congestion and HFpEF. In addition, increased AQP4 in the heart in the most aggressive form of HFpEF suggests a relevant role in cardiac oedema. Targeting AQPs in HFpEF may prevent oedema and decompensation. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): This study was supported from the Spanish Ministerio de Economía y Competitividad (RTI2018-096961-B-I00, SAF2015-65722-R and SAF2012-31451 to E.L-P. and Juan de la Cierva Incorporaciόn to M,V-O). The CNIC is supported by the Ministerio de Ciencia, Innovaciόn y Universidades (MCNU) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505).

Hydrogen production via microwave-induced water splitting at low temperature

This work was supported by the Spanish Government (RTI2018-102161, SEV-2016-0683 and Juan de la Cierva grant IJCI-2017-34110). We thank the support of the Electronic Microscopy Service of the Universitat Politecnica de Valencia.

The HDL dysfunction gains momentum: is it time for a new approach in rheumatic diseases?

J.R.-C. was supported by a postdoctoral contract from the Juan de la Cierva program (IJCI-2017-32070; Ministry of Science and Innovation, Spain) and Sara Borrell program (CD19/00120; Instituto de Salud Carlos III, Spain).

Toothpicking in early Homo OH 62 from Olduvai Gorge (Tanzania): An indirect evidence of intensive meat consumption?

A.E. is a Juan de la Cierva postdoctoral fellow (grant number: FJCI-2016-30122). This study has been partially funded by project CGL2012-36682 and project CGL2016-75109-P (Spanish Ministry of Economy and Competitivity, Agencia Estatal de Investigacion (AEI) and FEDER EU).

Does waste feed from salmon farming affect the quality of saithe ( Pollachius virens L.) attracted to fish farms?

The study was funded by the Norwegian Seafood Research Fund through the ProCoEx project (Project number: 900772) and the Norwegian Research Council through the project ‘ECOCOAST’. Kilian Toledo‐Guedes was supported by a grant from Iceland, Liechtenstein and Norway through the EEA Financial Mechanism (ES07‐EEA Grants, 013‐ABEL‐IM‐2013), operated by Universidad Complutense de Madrid, and Juan de la Cierva Program FJCI‐2014‐20100 and IJCI‐2017‐34174 from Ministerio de Ciencia, Innovacion y Universidades.

A comparative study on the reactive compatibilization of melt-processed polyamide 1010/polylactide blends by multi-functionalized additives derived from linseed oil and petroleum

This research work was funded by the Spanish Ministry of Science, Innovation, and Universities (MICIU) project numbers MAT2017-84909-C2-2-R and AGL2015-63855-C2-1-R. Quiles-Carrillo and Torres-Giner are recipients of a FPU grant (FPU15/03812) from the Spanish Ministry of Education, Culture, and Sports (MECD) and a Juan de la Cierva contract (IJCI-2016-29675) from MICIU, respectively. Microscopy services at UPV are acknowledged for their help in collecting and analyzing FESEM images. Authors thank Polyscope for kindly supplying XibondTM 920 for this study.

Bioengineering Tools to Aid the Study of Oral Processing Deficiencies: A Pathway to Tailored Food Products

The authors are grateful to the Spanish Ministry of the Economy, Industry and Competitiveness (AGL-2016-75403-R), and to the regional government (Generalitat Valenciana Project Prometeo 2017/189), for financial support. Author Laura Laguna thanks the Spanish “Juan de la Cierva” program for her contract (IJCI-2016-27427).

Tropical nights on the Spanish Mediterranean coast, 1950-2014

R.S.N. was funded by a 'Juan de la Cierva' postdoctoral grant FJCI-2017-31595. J.M. thanks the Spanish Ministerio de Economia y Competitividad and the European Regional Development Fund (FEDER) through the project CGL2015-64268-R (MINECO/FEDER, UE). O.M.R. thanks the Climatology Group (2017SGR1362, Catalan Government) and the CLICES Project (CGL2017-83866-C3-2-R).

About the Contributors

About the Contributors

Optimization of Microwave-Assisted Extraction of Phenolic Compounds with Antioxidant Activity from Carob Pods

This research was supported by the Spanish Ministry of Science, Innovation and Universities (MICIU) programs MAT2017-84909-C2-2-R and AGL2015-63855-C2-1-R and by the EU H2020 project YPACK (reference number 773872). Quiles-Carrillo wants to thank GV for his FPI grant (ACIF/2016/182) and MECD for his FPU grant (FPU15/03812). Torres-Giner also thank MINECO for his Juan de la Cierva contract (IJCI-2016-29675).

OR23-3 Differential Effects of Chronic Exposure to Bisphenol-A on Ion Channel Activity and Expression in Mouse Pancreatic Beta-Cells

Many dairy products found in plastics, cosmetics and food containers disrupt human health due to their actions as endocrine-disrupting chemicals (EDCs). Studies in different cellular and animal models have reported that low doses of the EDC bisphenol A (BPA), modify pancreatic β-cell function, induce insulin resistance and other metabolic alterations. Here, we aimed to investigate whether administration of low doses of BPA could regulate ion channels expression and function in mice pancreatic islets. For this purpose, we used microarrays to analyze the global gene expression profile, focusing on the modulation of ion channels-related genes. For in vivo experiments, mice were subcutaneously injected with BPA (100 μg/kg/day during 4 days). Islets were isolated 12 h after the last injection and prepared for RNA extraction and hybridization on Affymetrix GeneChip Mouse Genome 430 2.0 Array. Array scanning and data analysis were performed using Affymetrix Expression Console and the Affymetrix Transcriptome Analysis Console (TAC) Softwares. Expression level analysis was performed using the normalization method based on the processing algorithm called robust multi-array average (RMA). Whole islets or dispersed islets from C57BL/6 or estrogen receptor beta knockout (βERKO) mice were treated in vitro with BPA or vehicle during 48 h. Whole-cell patch-clamp recordings were used to measure sodium and potassium currents. Microarray analysis of islets isolated from mice treated with BPA showed that some ion channels, such as sodium channel voltage-gated type IX, alpha (Scn9a), potassium large conductance calcium-activated channel alpha member 1 (Kcnma1), and Kv channel-interacting protein 1 (Kcnip1), were modulated. These results were confirmed by quantitative RT-PCR. Electrophysiological measurements showed a decrease in both sodium currents and total potassium currents. Additionally, the currents through the voltage-gated potassium channel subunits Kv2.1 and 2.2 as well as the KCa1.1 (encoded by Kcnma1 gene) channels were also reduced. Interestingly, beta-cells from βERKO mice did not present such reductions, suggesting that these effects occur mainly via ERβ. Our results show that, acting as a xenoestrogen, BPA modulates sodium and potassium currents as well as gene expression via ERβ. Funding: Ministerio de Economia y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER), EU Grants SAF2014-58335-P, BFU2017-86579-R, BFU2016-77125-R and Generalitat Valenciana PROMETEO II/2015/016. LM holds a Juan de la Cierva fellowship from the Ministry of Economy, Industry and Competitiveness (IJCI-2015-24482). CIBERDEM is an initiative of the Instituto de Salud Carlos III. J-AG was supported by the Robert A. Welch Foundation (E-0004).