Rechargeable potassium–selenium (K–Se) batteries, as an emerging electrochemical energy storage system, has recently captured intensive attention due to the desirable natural abundance and low redox ...potential of elemental potassium as well as the relatively high electronic conductivity and impressive theoretical volumetric capacity of elemental selenium. Although great progress on cathode materials design and electrochemical performance improvement has been made, K–Se batteries are still confronted with a series of key challenges, including low reactive activity, shuttle effect, volume expansion, potassium dendrite growth, and high chemical activity of potassium metal. The recent advances in rechargeable K–Se batteries are comprehensively summarized with an emphasis on discussing the electrochemical mechanisms and central challenges, presenting the synthesis, properties, and electrochemical performance of selenium‐based cathode materials, and extending potential tactics for tackling the key issues and developmental directions for future research.
Rechargeable potassium–selenium (K–Se) batteries are comprehensively discussed for the first time, involving their mechanisms, central challenges, materials, and potential tactics beyond current materials engineering. Some perspectives regarding future developmental directions of K–Se batteries are also put forward to promote their further progress.
A quantitative description is presented of the dynamical process of polymer intercalation into clay tactoids and the ensuing aggregation of polymer‐entangled tactoids into larger structures, ...obtaining various characteristics of these nanocomposites, including clay‐layer spacings, out‐of‐plane clay‐sheet bending energies, X‐ray diffractograms, and materials properties. This model of clay–polymer interactions is based on a three‐level approach, which uses quantum mechanical and atomistic descriptions to derive a coarse‐grained yet chemically specific representation that can resolve processes on hitherto inaccessible length and time scales. The approach is applied to study collections of clay mineral tactoids interacting with two synthetic polymers, poly(ethylene glycol) and poly(vinyl alcohol). The controlled behavior of layered materials in a polymer matrix is centrally important for many engineering and manufacturing applications. This approach opens up a route to computing the properties of complex soft materials based on knowledge of their chemical composition, molecular structure, and processing conditions.
The unusual materials properties of clay–polymer nanocomposites are investigated through a chemically specific multiscale modeling scheme. This commences at the quantum‐mechanical level and systematically transfers information through an atomistic representation to a coarse‐grained description that describes the dynamics of polymer intercalation into the clay galleries and the ensuing evolution of the microstructure, whose materials properties can thereby be predicted.
Understanding the maintenance and dynamics of phenotypic polymorphisms requires unpicking key ecological mechanisms shaping the fitness costs and benefits of expressing alternative phenotypes, ...generating selection. Seasonal migration versus year‐round residence expressed in partially migratory populations represents one common polymorphism that can experience strong selection through differential reproductive success. Yet, key hypothesised pathways that could generate such selection remain to be empirically tested.
One hypothesis is that migratory tactics affect subsequent reproductive success through carry‐over effects on breeding site retention and resulting breeding dispersal. By remaining in breeding areas all year round, residents could retain their preferred breeding site between years, and consequently have higher reproductive success. Conversely, migrants that escape harsh non‐breeding season conditions could return in better condition, with high resource holding potential, and outcompete residents to retain their site. Such effects could further depend on migration timing and vary between years. Yet, such pathways have not been quantified, precluding empirical parameterisation of partial migration theory.
We used 4 years of breeding and non‐breeding season data from partially migratory European shags (Gulosus aristotelis) to test whether the three most frequent migratory tactics in this population (full resident, early migrant departing soon after breeding, and late migrant departing in late autumn) differed in their breeding site retention; whether site retention predicted reproductive success; and hence whether effects of migratory tactic on reproductive success were explicable through site retention.
Overall, residents were much more likely to retain their breeding site between years than both early and late migrants, and site retention was associated with increased reproductive success. Yet, these effects varied somewhat among years: late migrants were always least likely to retain their site but had variable relative reproductive success. Path analyses revealed that effects of migratory tactic on reproductive success were only partly attributable to breeding site retention.
These results indicate that multiple mechanisms underlie reproductive selection on migratory tactics, potentially contributing to maintaining behavioural polymorphisms. Yet, the clear associations between migratory tactics and local breeding dispersal reveal that these movements can be strongly interlinked across seasons, shaping overall spatioseasonal dynamics in partially migratory systems.
We show that migration and dispersal, two key ecological processes and important movement decisions, can be interlinked: migration can have carry‐over effects on reproductive success through nest site retention and hence reproductive dispersal propensity.
For multi-agent systems with switching topologies, the work addresses the fault-tolerant leader-following consensus issue. A semi-Markov chain is applied to describe randomly topological switching ...which may be caused by the complexity of network communication. In addition, in order to improve the utilization of bandwidth and relieve the burden of the communication channels in the multi-agent networks, a fault-tolerant event-triggered control protocol is developed to obtain the leader-following consensus of the multi-agent systems. By constructing an appropriate Lyapunov–Krasovskii functional and using some novel inequalities, the sufficient conditions of leader-following consensus are derived. One numerical simulation example validates the effectiveness of the presented method at length.
This study aimed to analyse the influence of the “no-ad scoring” or “gold point” rule on performance in professional padel, observing the differences between winners and losers, as well as between ...gender, game rounds and sets. For this, all the quarter-final, semi-final and final matches were analyzed, both in the male category (n = 100) and female (n = 74) of 15 tournaments of the World Padel Tour circuit in 2021. A total of 838 “gold points” were analyzed. The results show a higher percentage of games with gold points are played in women's padel than in men's padel (28.19 ± 9.24% vs 23.48 ± 10.51%; p<.001), with differences depending on the game round and the match set (p=.001). Winner pairs score significantly more gold points than losing pairs, both male (3.17±1.79 vs 2.24±1.87) and female (4.01±2.01 vs 2.54±1.72). Additionally, female winning pairs win significantly (p <.05) more gold points than male winning pairs. In conclusion, winning the gold point may be a key factor of performance in padel. In female players more differences are observed between winning and losing couples. In addition, in women's padel there is greater equality in the games score, due to the higher % of games with gold points. However, as the rounds progress, the men's padel is more equal even with respect to the score of the set, due to a higher number of games played, especially in the semifinals and final.
El objetivo de este estudio fue analizar la influencia de la regla del punto de oro en el rendimiento en pádel profesional, observando las posibles diferencias existentes entre ganadores y perdedores, así como entre género, rondas de juego y sets. Para ello, se analizaron todos los partidos de cuartos de final, semifinales y finales, tanto en categoría masculina (n=100), como femenina (n= 74) de 15 torneos del circuito World Padel Tour de 2021, con un total de 838 puntos de oro. Los resultados muestran que en el pádel femenino se disputan un mayor porcentaje de juegos con puntos de oro que en pádel masculino (28.19±9.24% vs 23.48±10.51%; p<.001), existiendo diferencias según la ronda de juego y el set del partido (p=.001). Las parejas ganadoras consiguen significativamente más puntos de oro ganados que las perdedoras, tanto en masculino (3.17±1.79 vs 2.24±1.87) como en femenino (4.01±2.01 vs 2.54±1.72). Además, las parejas ganadoras femeninas ganan significativamente (p<.05) más puntos de oro que las masculinas. En conclusión, ganar el punto de oro parece ser un factor de rendimiento en pádel, existiendo mayores diferencias en el género femenino entre ganadores y perdedores. Además, el mayor % de juegos con puntos de oro en pádel femenino indica una mayor igualdad en el juego. Sin embargo, a medida que avanzan las rondas, el pádel masculino es más igualado respecto al marcador del set, por un mayor número de juegos disputados, sobre todo en semifinales y final.
Oogenesis in fishes follows a universal plan; yet, due to differences in the synchrony and rate of egg development, spawning frequency varies from daily to once in a lifetime. Some species spawn and ...feed in separate areas, during different seasons, by storing energy and drawing on it later for reproduction (i.e. capital breeding). Other species spawn using energy acquired locally, throughout a prolonged spawning season, allocating energy directly to reproduction (i.e. income breeding). Capital breeders tend to ovulate all at once and are more likely to be distributed at boreal latitudes. Income breeding allows small fish to overcome allometric constraints on egg production. Income breeders can recover more quickly when good‐feeding conditions are re‐established, which is a benefit to adults regarding bet‐hedging spawning strategies. Many species exhibit mixed capital‐ and income‐breeding patterns. An individual's position along this capital–income continuum may shift with ontogeny or in relation to environmental conditions, so breeding patterns are a conditional reproductive strategy. Poor‐feeding environments can lead to delayed maturation, skipped spawning, fewer spawning events per season or fewer eggs produced per event. In a few cases, variations in feeding environments appear to affect recruitment variability. These flexible processes of energy acquisition and allocation allow females to prioritize their own condition over their propagules' condition at any given spawning opportunity, thereby investing energy cautiously to maximize lifetime reproductive value. These findings have implications for temporal and spatial sampling designs, for measurement and interpretation of fecundity, and for interpreting fishery and ecosystem assessments.
Cyber Supply Chain (CSC) system is complex which involves different sub-systems performing various tasks. Security in supply chain is challenging due to the inherent vulnerabilities and threats from ...any part of the system which can be exploited at any point within the supply chain. This can cause a severe disruption on the overall business continuity. Therefore, it is paramount important to understand and predicate the threats so that organization can undertake necessary control measures for the supply chain security. Cyber Threat Intelligence (CTI) provides an intelligence analysis to discover unknown to known threats using various properties including threat actor skill and motivation, Tactics, Techniques, and Procedure (TT and P), and Indicator of Compromise (IoC). This paper aims to analyse and predicate threats to improve cyber supply chain security. We have applied Cyber Threat Intelligence (CTI) with Machine Learning (ML) techniques to analyse and predict the threats based on the CTI properties. That allows to identify the inherent CSC vulnerabilities so that appropriate control actions can be undertaken for the overall cybersecurity improvement. To demonstrate the applicability of our approach, CTI data is gathered and a number of ML algorithms, i.e., Logistic Regression (LG), Support Vector Machine (SVM), Random Forest (RF), and Decision Tree (DT), are used to develop predictive analytics using the Microsoft Malware Prediction dataset. The experiment considers attack and TTP as input parameters and vulnerabilities and Indicators of compromise (IoC) as output parameters. The results relating to the prediction reveal that Spyware/Ransomware and spear phishing are the most predictable threats in CSC. We have also recommended relevant controls to tackle these threats. We advocate using CTI data for the ML predicate model for the overall CSC cyber security improvement.
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