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Na-ion batteries are growing interest due to their sustainability and low cost. A wide implementation in stationary applications, but also for short range transportation, is envisaged. This is further supported by the recent progress on Na-ion cells with increased energy density. To this regards, the development of procedures for real-time assessment of batteries state of health is of crucial relevance. The present paper provides an innovative procedure to assess sodium-ion battery capacity fading based on the application of discrete wavelet transform to voltage signals, acquired once a certain load pattern is applied at the battery terminals. The procedure development is provided through Na-ion cell aging test. During all the test battery capacity measurements are carried out. Root mean square error (RMSE) between assessed and measured values equals 1.18%. Moreover, during the aging test significant differences between performance evolution of Na-ion and NCR Li-ion cells are highlighted and discussed.

Herein, a large‐area nanofabrication process is proposed for flexible, ultrathin, and ultrasmooth gold films with extraordinary electro‐optical performance, making them competitive as transparent conductive electrodes (TCEs). The approach circumvents the thermodynamic constraints associated with the physical deposition of thin film electrodes, where 3D growth and metal dewetting delay stable percolation until the deposited film thickness exceeds 8–10 nm. It is demonstrated that a postgrowth ion irradiation procedure of compact gold films with Ar+ beam at very low energies, around 100 eV, predominantly induces ballistic smoothing and grain boundary restructuring. This process finally leads to the formation of ultrasmooth and ultrathin gold films that remain compact even at a thickness of 4 nm, with a sheet resistance in the range of 60 Ω sq−1 and an optical transparency around 80%. Remarkably, the films remain percolated even at thicknesses as low as 3 nm, with a transparency exceeding 90% and a sheet resistance of 190 Ω sq−1. These figures are comparable to those of commercial TCEs and enable simple, scalable, all‐metal transparent contacts on both rigid and flexible substrates, with significant potential for optoelectronic applications.

Among the relevant aspects of the family resemblance approach (FRA), our study focuses on the potential of the approach to elaborate on disciplinary identities in an interdisciplinary context, specifically regarding the interplay between physics and mathematics. We present and discuss how the FRA wheel can be used and intertwined with the framework of boundary objects and boundary crossing mechanisms (Akkerman & Bakker, "Review of Educational Research," 81, 132-169, 2011), which is well-known in STEM education for dealing with interdisciplinarity. The role of the FRA discussed in the article is dual: both practical and theoretical. It is practical in that we show how its use, in combination with the Akkerman and Bakker framework, appears effective in fostering productive discussions among prospective teachers on disciplinary identities and interdisciplinarity in historical cases. It is theoretical in that the combination of the two frameworks provides the vocabulary to characterise the 'ambiguous nature' of interdisciplinarity: like boundaries, interdisciplinarity both separates disciplines, making their identities emerge, and connects them, fostering mechanisms of crossing and transgressing the boundaries. This empirical study reveals how the theoretical elaboration took advantage of the prospective teachers' contributions. We initially presented the FRA to characterise disciplinary identities, but the prospective teachers highlighted its potential to characterise also the boundary zone and the dialogue between physics and mathematics. The data analysis showed that the combinination of the two frameworks shaped a complex learning space where there was room for very different epistemic demands of the prospective teachers: from those who feel better within the identity cores of the disciplines, to those who like to inhabit the boundary zone and others who like to re-shape boundary spaces and move dynamically across them.

Abstract Heavy‐metal‐free III–V colloidal quantum dots (QDs) exhibit promising attributes for application in optoelectronics. Among them, InAs QDs are demonstrating excellent optical performance with respect to absorption and emission in the near‐infrared spectral domain. Recently, InAs QDs attained a substantial improvement in photoluminescence quantum yield, achieving 70% at a wavelength of 900 nm through the strategic overgrowth of a thick ZnSe shell atop the InAs core. In the present study, light‐emitting diodes (LEDs) based on this type of InAs/ZnSe QDs are fabricated, reaching an external quantum efficiency (EQE) of 13.3%, a turn‐on voltage of 1.5V, and a maximum radiance of 12 Wsr−1m−2. Importantly, the LEDs exhibit an extensive emission dynamic range, characterized by a nearly linear correlation between emission intensity and current density, which can be attributed to the efficient passivation provided by the thick ZnSe shell. The obtained results are comparable to state‐of‐the‐art PbS QD LEDs. Furthermore, it should be stressed not only that the fabricated LEDs are fully RoHS‐compliant but also that the emitting InAs QDs are prepared via a synthetic route based on a non‐pyrophoric, cheap, and commercially available as precursor, namely tris(dimethylamino)‐arsine.

El obispo Miguel Hesayne (1975-1993) se constituyó tempranamente en una figura destacada en la escena política rionegrina debido a su intervención en el conflicto obrero suscitado en la mina de Sierra Grande (1975). Posteriormente, su posición frente a la última dictadura militar (1976-1983) trascendió los límites provinciales transformándolo en una referencia nacional en la defensa de los derechos humanos. Con el retorno de la democracia, Miguel Hesayne impulsó una de sus principales iniciativas en materia comunicacional que fue la publicación de la revista De Pie (1984-1989), un instrumento de denuncia y de acción política. En el presente artículo nos proponemos analizar las intervenciones del obispo en la sección “Dígame, padre” en torno al proceso democrático abierto en la Argentina a fines de 1983, para identificar su posición sobre la transición y el rol histórico que le cabía a la Iglesia rionegrina en la construcción de una democracia “real”.

Species of the genus Pimelodella (Eigenmann & Eigenmann, 1988) present many similar morphological characteristics, which makes taxonomic identification difficult. Some species present morphological distinction and reproduce normally, while others present reproductive isolation without morphological distinction. Taking that into consideration, we used starch-gel electrophoresis of enzymes to compare two species of the genus Pimelodella collected in Paraná, Ivaí and Pirapó rivers of the Upper Paraná River basin. We analyzed the liver and muscle tissue of 82 Pimelodella avanhandavae and 29 Pimelodella gracilis individuals, which revealed few genetic differences between species. In addition, we carried out an experimental design based on the separation of four populations: P. avanhandavae, Parana River (n = 37); P. avanhandavae, Ivaí River (n = 6); P. gracilis, Ivaí River (n = 29); P. avanhandavae, Pirapó River (n = 39). The high proportions of polymorphic loci as well as the expected heterozygosity suggest that both species have high genetic variability. Nei’s genetic identity values and Wright's fixation indices revealed a large genetic proximity between the samples collected in Ivaí and Pirapó rivers, regardless of the species analyzed. The presence of fixed alleles at one hundred percent for two loci showed that P. avanhandavae individuals collected in the Parana River are genetically distant from all remaining populations. Data indicated that P. avanhandavae, collected in this river, constitutes a distinguished species from those collected in Ivaí and Pirapó rivers. Therefore, we suggest, that more studies with molecular markers be carried out with the genus, as well as a review of the diagnostic morphological characteristics used to separate P. avanhandavae from P. gracilis.

Background: Wave energy represents one of the most promising renewable energies due to its great theoretical potential. Nevertheless, the electrical compliance of grid-connected systems is a great issue nowadays, due to the highly stochastic nature of wave energy. Methods: In this paper, a Hybrid Energy Storage System (HESS) consisting of a Li-ion battery and a flywheel is coupled to a Wave Energy Converter (WEC) that operates in grid connected mode. The study is performed using real yearly wave power profiles relating to three different sites located along the European coasts. The Simultaneous Perturbation Stochastic Approximation (SPSA) principle is implemented as real-time power management strategy for HESS in wave energy conversion systems. Results: Obtained results demonstrate how the proposed HESS and the implementation of the SPSA power management coupled to a WEC allow a reduction of more than 80% of power oscillations at the Point of Common Coupling (PCC), while proving the robustness of the developed management strategy over the investigated sites. Moreover, the average energy penalty due to the HESS integration results slightly higher than 5% and battery solicitation is reduced by more than 64% with respect to the flywheel solicitation, contributing to extend its lifetime. Conclusions: HESS integration in renewable generation systems maximizes the WEC production while smoothing the power at the PCC. Specifically, flywheel-battery HESS together with the implemented power management strategy could provide a great flexibility in the view of increasing power production from waves, strongly mitigating the variability of this source while enhancing grid safety and stability.

ABSTRACT The common bean, a legume of significant economic importance, is renowned for its extensive genetic variability. It is crucial to comprehend genetic diversity, analyze population structure, and understand relationships among commercial classes of accessions to facilitate genetic improvement. This study aimed to molecularly characterize 143 common bean accessions by employing 25 SSR molecular markers. The objectives were to estimate genetic diversity, analyze genetic structure, and cluster populations using the UPGMA and PCoA methods. A total of 105 alleles were amplified using microsatellite loci, and the observed heterozygosity was lower than expected across all loci, indicating inbreeding within the populations. Among the loci, 22 were highly informative, demonstrating their effectiveness and polymorphism in detecting genetic diversity. The genetic variability within the population was found to be the highest, while variation between populations was the lowest. The analysis of population structure revealed the presence of three populations with a notable rate of gene introgression. The UPGMA analysis categorized the accessions into 15 groups, but they did not form distinct clusters based on their geographic regions or gene pool. The first two principal coordinates accounted for 13.95% of the total variation among the accessions. The SSR markers employed effectively detected genetic variability among the common bean accessions, revealing that their genetic diversity was not correlated with their geographic distribution in this study.

Beyond solar and wind energy, wave energy is gaining great interest due to its very high theoretical potential, although its stochastic nature causes intermittent and fluctuating power production. Energy storage system (ESS) integration to wave energy converter (WEC) plants represents a promising solution to mitigate this issue. To overcome the technological limits of the single storage devices, the hybridization of complementary ESSs represents an effective solution, extending the operating range over different timeframes. This paper analyzes the benefits of Li-ion battery–supercapacitor hybrid ESS integration into a grid-connected WEC, aiming at smoothing the produced power oscillations. The hybridization concept involves coupling a power-intensive technology, such as a supercapacitor devoted to managing fluctuations at higher frequency, with a battery technology exploited to manage power variations over longer timeframes to mitigate degradation issues. In this study, a multi-objective data-driven power management strategy, based on the simultaneous perturbation stochastic approximation (SPSA) algorithm, is implemented to minimize power fluctuations in terms of power ramp (representing the power variation between two consecutive values with a 1 s time step), both at the Point of Common Coupling (PCC) and the Li-ion battery terminals, thanks to the supercapacitor peak-shaving function. The SPSA management strategy, together with a suitable sizing procedure, allows a reduction of more than 70% in the power oscillations at the PCC with respect to those at the WEC terminals, while decreasing battery stress by more than 25% if compared to a non-hybrid ESS consisting of a Li-ion battery. This shows how supercapacitor features can extend battery lifespan when integrated in a hybrid ESS.

This article takes its point of departure from the younger generation's problematic relationship with time and the future. A general sense of changeability and directionlessness in society compromises young people's confidence in themselves to make a difference as individuals in important global issues affecting their futures, such as climate change. Given recent aims and commitments of science education to promote sustainable development and student agency, this study explores how science teaching can help students imagine and face possible future scenarios and develop agency in the present to influence them. This article presents a science education approach to equip secondary school students with skills of futures thinking and agency that we call "future-scaffolding skills." It also shows the process of building an operational definition for recognizing those skills in students' discourse and actions. For this purpose, an empirical study was carried out in the context of a teaching--learning module on climate change, consisting of activities inspired by the field of futures studies. Essays, individual and group interviews, questionnaires, and video recordings of students' final projects were collected from 24 students (16-19-years old) from three European countries. The results contribute to operationally defining "future-scaffolding skills," consisting of "structural skills" (the ability to recognize temporal, logical and causal relationships and build systemic views) and "dynamical skills" (the ability to navigate scenarios, relating local details to global views, past to present and future, and individual to collective actions).

The crisis due to the COVID-19 pandemic led most people all over the world to deal with a change in their perception and organization of time. This happened also, and mainly, within the educational institutions, where students and teachers had to rearrange their teaching/learning dynamics because of the forced education at a distance. In this paper, we present an exploratory qualitative study with secondary school students aimed to investigate how they were experiencing their learning during lockdown and how, in particular, learning of science contributed to rearranging their daily lifetime rituals. In order to design and carry out our investigation, we borrowed constructs coming from a research field rather unusual for science education: the field of "sociology of time." The main result concerns the discovery of the potential of the dichotomy between "alienation from time" and "time re-appropriation." The former is a construct elaborated by the sociologist Hartmut Rosa to describe the society of acceleration in the "era of 'future shock'". The latter represents an elaboration of the construct of "appropriation" that the authors had operationally defined, starting from Bakhtin's original idea, to describe the nexus between physics learning and identity. Thanks to the elaboration of the notion of "time re-appropriation" as feature of the "era of 'present shock'", the study unveils how school science, instead of preparing the young to navigate our fast-changing and complex society, tends to create "bubbles of rituals" that detach learning from societal concern.

Herein, a large‐area nanofabrication process is proposed for flexible, ultrathin, and ultrasmooth gold films with extraordinary electro‐optical performance, making them competitive as transparent conductive electrodes (TCEs). The approach circumvents the thermodynamic constraints associated with the physical deposition of thin film electrodes, where 3D growth and metal dewetting delay stable percolation until the deposited film thickness exceeds 8–10 nm. It is demonstrated that a postgrowth ion irradiation procedure of compact gold films with Ar+ beam at very low energies, around 100 eV, predominantly induces ballistic smoothing and grain boundary restructuring. This process finally leads to the formation of ultrasmooth and ultrathin gold films that remain compact even at a thickness of 4 nm, with a sheet resistance in the range of 60 Ω sq−1 and an optical transparency around 80%. Remarkably, the films remain percolated even at thicknesses as low as 3 nm, with a transparency exceeding 90% and a sheet resistance of 190 Ω sq−1. These figures are comparable to those of commercial TCEs and enable simple, scalable, all‐metal transparent contacts on both rigid and flexible substrates, with significant potential for optoelectronic applications. [ABSTRACT FROM AUTHOR]

In this paper, we address the confidence of the agricultural producers in their prosperity as a driver of development. The agricultural sector development is highly dependent on short term investment decisions for sowing area, breeding, among others, which in turn is mediated by confidence. Agricultural producer confidence is continually measured in Argentina by CREA, a non-profit organisation composed of groups of producers spread across the country striving for innovation and best practices diffusion. We leverage this measurement methodology to propose a structural equation model to explain confidence by an exhaustive collection of factors affecting the business at company, sector or economy level, providing critical insight about the range of policies that would enable agriculture to grow. High regulation and tax burdens prevailing in the market during the past decades have been identified as relevant hindrance factors to confidence. On the enablers side are the respect for property rights and the organisation effectiveness actively fostered by CREA. [ABSTRACT FROM AUTHOR]

We study an economy with traders whose payoffs are quasilinear and whose private signals are informative about an unobserved state parameter. The limit economy has infinitely many traders partitioned into a finite set of symmetry classes called types. Market mechanisms in a class that includes auctions yield the same outcome as the Walrasian rational expectations equilibrium if and only if the efficient allocation has a monotonicity property. Examples illustrate cases where they differ. Monotonicity restricts the heterogeneity among traders' types. [ABSTRACT FROM AUTHOR]

Abstract The current decline of mammals worldwide makes quantitative population assessments crucial, especially for range‐restricted and threatened species. However, robust abundance estimations are challenging for elusive or otherwise difficult to detect species. Alternative metrics requiring only presence/absence data, that is, occupancy, are possible but calibration with independent density estimates should be foreseen, although rarely performed. Here, we calibrated density estimates from acoustic surveys to occupancy estimates from camera‐trapping detections to derive the abundance of the endangered Sanje mangabey (Cercocebus sanjei) across its entire range in the Udzungwa Mountains of Tanzania. We found marked occupancy–density relationships for the two forest blocks where this primate occurs and used them to derive spatially explicit density estimates. Occupancy increased in montane forest zones at mid‐elevation but decreased slightly with proximity to forest borders. We predicted an average density (±SE) of 0.26 ± 0.05 groups/km2 in the national park and 0.24 ± 0.06 in the nature reserve. Accordingly, and given the much larger area of the reserve, the average predicted individual abundance was 1555 ± 325 and 2471 ± 571 in the national park and nature reserve, respectively. We found higher density and abundance in the nature reserve compared with previous studies. Given the past disturbance and poorer protection in the nature reserve relative to the national park, our results instill optimism for the status of the species, although occupancy analysis highlighted the potential vulnerability of this primate to human disturbance. Our approach appears valuable for spatially explicit density estimations of elusive species, and provides robust assessments of vulnerability and identification of priority areas for conservation of threatened populations.