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Solar-driven synthesis of CaS-decorated activated carbon from pecan nutshell agro-industrial waste to assemble green, stable, and electro-activated supercapacitors
No full text10 figures, 3 tables.Developing efficient energy storage devices is crucial in a growing trend toward using electromobility and renewable energy sources. This study focuses on preparing environmentally friendly supercapacitors by synthesizing activated carbon decorated with semispherical CaS nanoparticles of approximately 30 nm in size. Pecan nutshells (Carya illinoinensis) were used as a carbon and calcium source, whereas (NH4)2SO3 was used both as a novel activating agent and a CaS precursor, enabling the formation of CaS-decorated activated carbons, as discussed in this work, for the first time. Activated carbon was prepared using a high-flux solar radiation furnace (SF) and a conventional tube furnace (TF). The synthesis temperature and concentration of the activating agent were determined using a factorial experimental design with central set points at 400, 600, and 800 °C and 1, 2, and 3 M. Physicochemical analysis revealed that temperature had a statistically significant effect on the surface area and degree of graphitization of the synthesized materials only when the TF method was used. The carbonaceous materials were electrochemically characterized in a 3-electrode cell to investigate their energy storage properties as supercapacitor electrodes. The highest electrochemical capacitance (≈180 Fg−1) was obtained in a potential window of 2 V. In addition, the best carbon-based material was tested as a supercapacitor electrode and exhibited a specific energy of 14.42 Wh/kg, increasing by 50 % after 15,000 cycles, highlighting its electro-activation characteristics. Even though metal sulfides have been extensively used for supercapacitors, this is the pioneering work harnessing biomass-derived carbons decorated with calcium sulfide nanoparticles for supercapacitors.
Concentrated solar energy enables the preparation of biomass-derived activated carbon decorated with Calcium Sulfide (CaS) nanoparticles, using Ammonium Sulfite ((NH4)2SO3) as a novel activating agent and CaS precursor towards the valorization of pecan nutshell waste and the green-tailored fabrication of efficient carbon-based supercapacitors for energy storage. This study examines the solar-assisted preparation, physicochemical characterization, and electrochemical energy storage properties of biomass-derived activated carbon decorated with CaS nanoparticles.O. Soto-Díaz, A. Ayala-Cortés, and D.R. Lobato-Peralta thank CONAHCYT for their master's and PhD scholarship support.Peer reviewe
Model Predictive Control for a Mecanum-Wheeled Robot in Dynamical Environments
No full textTrabajo fin de máster presentado en la Universidad Politécnica de Cataluña, Master’s degree in Advanced Mathematics and Mathematical EngineeringMecanum-wheeled robots have been thoroughly used to automate tasks in many different
applications. However, these robots are usually controlled by neglecting their dynamics and
relying only on their kinematics alone. We model the behaviour of the robot by taking into
account both the robot’s geometry and the dynamic response of the actuators. All of the
parameters of the robot are calculated, including its moments of inertia and friction on the
actuators. We then introduce a controller for the system that takes into account the full nonlinear dynamic model of the robot by using Model Predictive Control. The controller is able
to meet non-linear inequalities such as input limits and obstacle avoidance. The controller
is very agile and can quickly adapt to changes in the environment. This allows control in
unpredictable environments and can generate fast and energy efficient maneuver
Supporting information for Solar-driven synthesis of CaS-decorated activated carbon from pecan nutshell agro-industrial waste to assemble green, stable, and electro-activated supercapacitors [Dataset]
No full textUnder a Creative Commons BY-NC-ND 4.0 license.Figure S1. a) TGA of pecan nutshell with insert of DTA analysis and b) indexed diffractogram of pecan nutshell; Figure S2. a) IER-UNAM solar furnace configuration and main components: a concentrator made up of 409 hexagonal-shaped mirrors, an 81m² sun-tracking flat heliostat, that follows the sun in two axes and to redirect solar rays to the solar concentrator, a shutter between the heliostat and the concentrator that modulates the solar power incident on the concentrator, and therefore, controlling the temperature in the focal zone, and a surface capable of moving along all three axes where the reactor is placed b) Pyrolysis reactor, and c) pyrolysis rector viewed from solar concentrator; Figure S3. Temperature profiles of the experiments carried out at the IER-UNAM solar furnace; Figure S4. Nitrogen adsorption isotherms for carbons produced in a) solar furnace, and b) tube furnace. Pore diameter distribution of c) SF materials and d) TF materials; Figure S5. Main effects plot shows respectively the effect of temperature and concentration on the graphitization degree of the carbons obtained in the solar furnace (a and c) and the tube furnace (b and d); Figure S6. High-resolution XPS spectra of materials obtained in the solar furnace: a) C1s region, and b) O1s region; Figure S7. High-resolution XPS spectra of materials obtained in the tube furnace: a) C1s region, and b) O1s region; Figure S8. Raman spectra for a) SF materials and b) TF materials. PL spectra of c) SF materials and d) TF materials; Figure S9. a) Schematic of thermocouples placed on and within the alumina crucible. b) Picture of the alumina crucible setting for an experiment (shutter fully closed in the background); Figure S10. Microstructure and element distribution maps of material SF800-1R; S1. Activation and CaS formation: S1.1. Activation and formation of CaS: Figure S11. DSC (Top) and TGA (bottom) thermograms for thermal decomposition of (NH4)2SO3·H2O, and impregnated pecan nutshell with 1M and 3M (NH4)2SO3 solutions at a) 5 °C/min and b) 20 °C/min; Table S1. Main observations by DSC and comparison between (NH4)2SO3·H2O theoretical mass loss and experimentally mass loss observed by TGA; Equation S1; Equation S2; Equation S3; Equation S4; Equation S5.O. Soto-Díaz, A. Ayala-Cortés, and D.R. Lobato-Peralta thank CONAHCYT for their master's and PhD scholarship support.Peer reviewe
Antifungal Peptides with Unexpected Structure from a Library of Synthetic Analogs of Host-Defense Peptide Rigin
No full textRising antifungal resistance prompted the World Health Organization and the Food and Agriculture Organization to bring attention to the consequences of this threat to human, animal, and environmental health, and food security. In addition, there is an alarming cross-species pathogenicity. New antifungal agents are urgently needed, preferably with a low induction of antimicrobial resistance (AMR). Among the most promising novel antimicrobials are the host-defense peptides, which present potent anti-infective properties and elicit low or negligible AMR. The rapid creation of libraries of host-defense peptides is highlighted by the synthesis of analogs of the immunomodulator and antimicrobial peptide rigin. Starting from smaller fragments incorporating hydroxyproline customizable units, which can be selectively cleaved and modified to give different lateral chains and N-substituents, two fragment libraries were built. Then the fragments were combined to give a library of rigin analogs, some of which displayed a potent antifungal activity not observed in the natural peptide. Surprisingly, the most active ones were N-substituted and lateral-chain protected analogs, while the free cationic peptides displayed low direct activity. This work shows that the strategy of combining site-selective peptide modification and a combinatorial approach can provide peptide-diverse libraries, where unexpected drug leads may be identified.This work was mainly financed by projects RETOS-SELECTFIGHT (PID2020-116688RB-C21/AEI/10.13039/501100011033/ERDF A way of making Europe) of the Plan Estatal I + D, Ministry of Science, Spain, with European Regional Development Fund, ERDF) and project 2022CLISA40 financed by Fundación CajaCanarias and Fundación La Caixa. We also acknowledge previous support from project ProID2020010134 (Programa de Subvenciones a la Realizacion I + D Ma Carmen Betancourt y Molina from ACIISI-Gobierno de Canarias with ERDF funds). D.H. also acknowledges her postdoctoral contract financed by project 2022CLISA40, and her previous contract financed by project TRANSALUDAGRO, sponsored by Cabildo de Tenerife, Program TF INNOVA 2016-21 (with MEDI & FDCAN Funds). M.P. carried out this work as a predoctoral student of the Ph.D. Program “Ciencias Médicas y Farmacéuticas, Desarrollo y Calidad de Vida” of the University of La Laguna (ULL), and thanks her predoctoral FPU grant from Ministerio de Ciencia, Innovacion y Universidades. We acknowledge Dr. Cristina Giménez (ULL) for her advice in the antifungal activity Section. Finally, we also acknowledge support of the publication fee by CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe
Effect of probiotics on sperm quality in the adult mouse
Get PDFThe administration of probiotics for the treatment of different diseases has gained interest in recent years. However, few studies have evaluated their effects on reproductive traits. The objective of this study was to examine the effect of two mixtures of probiotics, a commercial probiotic (Vivomixx®) and a mix of Lacticaseibacillus rhamnosus GG and Faecalibacterium duncaniae A2-165, on sperm quality in a mouse model. Adult male mice (8 months old) were used for two experimental and one control groups (n = 5 each). The probiotics or physiological serum (control) was administered orally, twice a week, during 5 weeks. Sperm were collected from the cauda epididymis, and their total number, motility, kinematics, morphology, and acrosome integrity were assessed in recently collected samples and after a 60-min in vitro incubation. Results showed a higher percentage of normal sperm in both experimental groups, with fewer head abnormalities than in the control. Differences were found among groups in the morphometry of sperm heads, being more elongated in mice treated with probiotics. Sperm from probiotic-treated mice showed similar total motility when compared to the controls, although the proportion of progressively moving sperm and their vigor of motility were lower. Sperm swimming descriptors were measured with a CASA system. Velocity parameters were similar among groups whereas linearity was higher in mice treated with the commercial probiotic. These results suggest that the administration of probiotics may increase the proportion of sperm with normal morphology and lead to modifications in sperm head shape that may enhance sperm swimming. Studies using a longer administration period would be useful in further characterizing the effect of these probiotic mixtures on sperm quality and fertilization capacity.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.This study was supported by the Spanish Ministry of Science and Innovation (projects CGL 2016–80577-P and PID 2019-108649 GB-I00). ASR was funded by a “Juan de la Cierva” postdoctoral fellowship from the Ministry of Science and Innovation, co-funded by the European Social Fund (FJC2019-041736-I). IIDI was supported by a grant from the Comunidad de Madrid (PEJ-2019-TL/AMB-15136). DRV was funded by a contract with the Agrupación de Interés Económico Probiosperm (ref. 228205) with the company BioCoRe S. Coop. C.S., V.G.C., and D.L. were funded by a contract (ref. 20196967) with BioCoRe S. Coop.Peer reviewe
Wie hoch stieg das Wasser der Sintflut? Neue Überlegungen zu Gen 7,20
No full text[EN] This article argues that the Hebrew text of Genesis 7:20 is to be understood in a different way from that previously assumed. The adverbial expression milemaˁlāh does not mean »upwards« or »higher than«, but »from above«. And the point of reference is not the tops of the high(est) mountains, but the base of the sky: »the water had swollen to (a height of) 15 cubits from above«. At the peak of the flood, the ark, which was 30 cubits high (Gen 6:15), just fitted in between the surface of the water and the sky.[DE] In diesem Artikel wird argumentiert, dass der hebräische Text von Genesis 7,20 anders zu verstehen ist als bisher angenommen wurde. Der adverbiale Ausdruck milemaˁlāh bedeutet nicht »nach oben hin« bzw. »höher als«, sondern »von oben her (gemessen)«. Und der Bezugspunkt sind nicht die Spitzen der hohen Berge, sondern vielmehr die Unterseite des Himmels: »Das Wasser war auf (eine Höhe von) 15 Ellen von oben her angeschwollen«. Auf dem Höhepunkt der Flut fand die Arche, die 30 Ellen hoch war (Gen 6,15), also gerade noch Platz zwischen Wasseroberfläche und Himmel.Peer reviewe
Design of catalysts for selective CO2 hydrogenation
No full textCO2 hydrogenation with green hydrogen is a practical approach for the reduction of CO2 emissions and generation of high-value added chemicals. Generally, product selectivity is determined by the associated reaction mechanisms, internal catalyst identity and structure, and external reaction conditions. Herein, we examine typical CO2 hydrogenation reaction pathways, which can provide insight useful for the atomic-level design of catalysts. We discuss how catalyst chemical states, particle sizes, crystal facets, synergistic effects, and unique structures can tune the product selectivity. Different catalysts such as Fe, Co, Ni, Cu, Ru, Rh, Pd-based and bifunctional structured catalysts and their influence on the CO2 hydrogenation products (such as CO, methane, methanol, ethanol and light olefins) are discussed. Beyond catalyst design, emerging catalytic reaction engineering methods for assisting the tuning of product selectivity are also discussed. Future challenges and perspectives in this field are explored to motivate the design of next-generation selective CO2 hydrogenation processes to facilitate the transition towards carbon neutrality.This work was supported by the Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars (No. 20232ACB213001), Thousand Talents Plan of Jiangxi Province (No. jxsq2023101072), National Natural Science Foundation of China (Nos. 22005296, 22362022), National Key Research and Development Program of China (No. 2022YFA1504500), and Natural Science Foundation of Jiangxi Province (No. 20224BAB213015). The authors also thank Prof. Can Li for his academic guidance and support.Peer reviewe
Insights into Organic Food Consumption in Tenerife (Spain): Examining Consumer Profiles and Preferences
No full textThis article belongs to the Section Sustainable Food.This paper explores consumer profiles and preferences for organic food on the island of Tenerife (Canary Islands, Spain). With a growing demand for organic products driven by health-consciousness and environmental concerns, understanding the factors that influence consumer behavior in this market is crucial. This study analyzes socio-demographic characteristics and market trends to uncover the motivations behind the demand for organic food through a survey of shoppers in stores selling certified organic products. By examining consumer awareness, perceived benefits, willingness to pay premium prices, proximity consumption patterns, and meat consumption, valuable insights are gained. Findings reveal that organic purchase habits and consumer profiles mostly align with the overall Spanish profile. A specific category of consumers who claim to follow a Mediterranean diet are identified as “switchers” who oscillate between organic and conventional produce without ideological and ethical commitment. Consumers clearly differentiate between the kinds of products they prefer to buy with organic or proximity attributes. Organic meat consumption correlates with a higher income and willingness to pay for it. By identifying distinct consumer profiles within the organic food market, this study provides actionable recommendations for businesses and policymakers to tailor their strategies and foster the growth of the organic food sector.This study was funded by the State Plan for Scientific and Technical Research and Innovation 2021–2023—Knowledge Generation Projects Ref. PID2021-126272OA-I00.Peer reviewe
Shining disco: shedding light into the systematics of the family Discodorididae (Gastropoda: Nudibranchia)
No full text15 pages, 7 figures, supplementary data https://doi.org/10.1093/zoolinnean/zlae170.-- Data availability: All data supporting this study's findings, including the online Supporting Information, are available within the article. Specimen vouchers have been deposited in the respective museums, and molecular data have been uploaded to GenBank. Detailed information on voucher specimens and GenBank accession numbers can be found in Supporting Information, Table S1The evolutionary relationships among genera within the nudibranch family Discodorididae remain poorly understood, with comprehensive molecular studies still largely absent. Discodoris, the most species-rich genus within this family, has historically represented a wastebasket taxon where species with ‘discodoridid’ morphology were placed. In this study, we present molecular data to evaluate the taxonomic classification of the family and to investigate potential (pseudo)cryptic diversity. Our molecular analyses comprised a multilocus phylogenetic analysis of 199 specimens, including 20 type species. The dataset included 142 specimens belonging to Discodorididae, 24 from Dorididae, and 33 outgroup taxa. A total of 52 specimens from 30 different species of Discodorididae, including six type taxa, were sequenced from the Mediterranean Sea, Eastern Atlantic Ocean, and Central and South America. Phylogenetic analyses recovered the monophyly of the family Discodorididae but including the doridid Aphelodoris, revealing evidence of hidden diversity in several genera such as Taringa, Tayuva, Paradoris, and Geitodoris. Our study unveiled the paraphyly of the genera Discodoris and Diaulula, which warrant a critical appraisal of their morphology. Overall, we provide relevant molecular information to infer the most complete phylogeny of Discodorididae to date and identify new questions for future studiesR. F-V. was supported by the Systematics Research Fund from the Linnean Society of London (UK), the Artenvielfalt erforschen und retten (https://www.artenforschung.de/, Germany), and the Travel Grant for the World Congress of Malacology 2022 from the Unitas Malacologica. Analytical work was supported by funding from M.A.A. (CGL2016-80651-P, 2021SGR689) and M.S. from the respective universities. J.M. is indebted to the Alexander von Humboldt Foundation (Germany) and the Spanish Government through the HETGEN1000 project (PID2021-127037NA-I00/MCIN/AEI/10.13039/501100011033/ and by FEDER una manera de hacer Europa)With the institutional support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe
Analysing Milk and Dairy Consumption in Ancient Societies: Bioarchaeological, Evolutionary and Human Social Perspectives
Get PDF[Background] In prehistoric societies, especially in the Neolithic period, the study of the palaeodiet assumes special importance as it is one of the points in human history characterised by important changes in diet. In this context, the study of food intolerances is even more significant.[Methods] Some of the individuals studied were analysed from a genetic point of view, while a systematic literature review was performed from a genetic perspective, verifying the persistence or absence of lactase in adulthood, and information from necropolises regarding the presence of biomarkers linked to possible consumption of dairy products was analysed. Results: The results indicate a clear majority of individuals with hypolactasia in adulthood, although in a Pyrenean necropolis, studied here for the first time, the lactase persistence allele was already detected. Dairy consumption was also verified to be widespread in very early Neolithic periods.[Conclusions] From a population perspective, this study enables a deeper understanding of past populations’ daily lives, expanding our perspective on their dietary patterns. From an evolutionary standpoint, it illuminates a pivotal point in human history and evolution within the European context, where past and modern dairy consumption, particularly cheese, has profound implications for both present and past economies.This work was supported by the G/6401400/8000 research project (Banco Santander-Universidad Complutense de Madrid, Spain) for C.G., the HAR2015-67323-C2-2-P project funded by the Ministerio de Ciencia, Innovación y Universidades of the Spanish Government (MICINN) and the PR41/17-21018 research project SANTANDER-UCM 2017 (PR41/17).Peer reviewe