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Abstract: Climate change and the increase of population pose challenges to ensuring suitable water supply in water-scarce regions. This work presents a comparative analysis of the water-supply approaches adopted in Los Angeles, Southeastern Spain, and Sydney. Results show a decrease in per-capita water use in the period 2000–2020, which reflects an improvement in water conservation. Social factors in the domain of hydropolitics and economic efficiency explain the divergence of water policies adopted. The adaptation to water scarcity and growing population in three regions of developed countries located in different continents sheds light on challenges facing the achievement of water security worldwide.

Purpose: This scoping review aims to identify the primary racket and arm-mounted technologies based on inertial measurement units that enable the quantification of hitting load in racket sports. Methods: A comprehensive search of several databases (PubMed, SPORTDiscus, Web of Science, and IEEE Xplore) and Google search engines was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) extension for scoping reviews guidelines. Included records primarily focused on monitoring hitting load in racket sports using commercialized racket or arm-mounted inertial sensors through noncompetitive and competitive racket-sports players. Results: A total of 484 records were identified, and 19 finally met the inclusion criteria. The largest number of systems found were compatible with tennis (n = 11), followed by badminton (n = 4), table tennis (n = 2), padel (n = 1), and squash (n = 1). Four sensor locations were identified: grip-attached (n = 8), grip-embedded (n = 6), wrist (n = 3), and dampener sensors (n = 2). Among the tennis sensors, only 4 out of the 11 (36.4%) demonstrated excellent reliability (>.85) in monitoring the number of shots hit either during analytic drills or during simulated matches. None of the other racket-sports sensors have undergone successful, reliable validation for hitting-volume quantification. Conclusions: Despite recent advancements in this field, the quantification of hitting volume in racket sports remains a challenge, with only a limited number of tennis devices demonstrating reliable results. Thus, further progress in technology and research is essential to develop comprehensive solutions that adequately address these specific requirements. [ABSTRACT FROM AUTHOR]

Abstract Additive manufacturing has enabled the design of thermoplastic components that provide structural support, electrical conductivity and heat generation modulated by mechanical deformation. The mechanisms and interplays that govern the material response at the microstructural level remain, however, elusive. Here, we develop an experimental method to characterise conductive filaments from a combined mechanical, electrical and thermal perspective. This approach is used to unravel exciting material interplays of conductive polylactic acid. To overcome experimental limitations that prevent a complete microstructural analysis of the problem, we develop a full-field homogenisation framework and implement it for finite elements. The framework accounts for viscoplasticity, electrical and thermal conduction, convection and heat generation via Joule effect, as well as for the interdependences between them. After experimental validation, the framework is applied to virtually optimise fabrication requirements to obtain desired properties in final products, i.e., stiffer products, filaments with higher conductivities or with better sensing capabilities.

La gran presión demográfica y un clima de rasgos semiáridos hacen que la disponibilidad de agua en el sur de California sea reducida. Diversos trasvases se han realizado con el objetivo de abastecer de agua a la aglomeración urbana de Los Ángeles. Recientemente, nuevas técnicas de desalación y reciclaje de aguas residuales son tomadas en consideración. El artículo realiza un recorrido histórico del suministro de agua a esta región y presenta un resumen de la situación actual.

Professional tennis competition at the highest levels requires high physical, technical, tactical, and mental demands. Player retirement is a scenario that often occurs at the highest echelons of the game. The objective of this study was to descriptively determine which factors influence retirement of matches in tennis. Matches from the Women's Tennis Association (WTA) and Association of Tennis Professionals (ATP) tours played over 44 and 46 years were included in the study, respectively. The results showed an increasing trend in the incidence of retirements in both ATP and WTA events, especially in recent years. Factors associated with the match characteristics, such as the type of surface, the type of tournament, and the round of the draw, were shown to influence retirement. Variables associated with player characteristics, such as the age difference between players, did not show to influence retirement, whereas the ranking difference did. When comparing ATP and WTA matches, similar results were observed in which surfaces and tournaments had the highest or lowest incidence of retirements. On the other hand, as per the rounds, the results are not conclusive. The findings highlight the growing trend of match retirements in professional tennis and emphasize the relevant influence of match characteristics such as surface type, tournament type, and round of the draw. These insights can guide coaches, players, and tournament organizers in developing strategies to mitigate retirements and inform future research on enhancing player longevity and performance in tennis. Highlights: An increasing trend in match retirements has been observed in both Association of Tennis Professionals (ATP) and Women's Tennis Association (WTA) events, especially in recent years, indicating a growing issue in professional tennis.Factors related to match characteristics, such as playing surface, tournament type, and round of the draw, have been identified as key influencers of match retirements.Player characteristics, specifically the age difference between players, do not significantly affect retirement, but the ranking difference does, highlighting its relevance.Similar patterns were found in ATP and WTA matches regarding the impact of playing surfaces and tournaments on retirement rates, while the influence of match rounds remains inconclusive. [ABSTRACT FROM AUTHOR]

Purpose: This research investigated the pre-, per- and post cooling strategies used by competitive tennis players from various levels of play who occasionally train and compete in hot (>28°C) and humid (>60% rH), and dry (<60% rH) environments. Methods: 129 male tennis players (Mage = 24.9) competing at regional (N = 54), national (N = 30) and international (N = 45) levels, completed an online questionnaire regarding their use (i.e., timing, type, justification and effectiveness) of pre- (i.e., before practice), per- (i.e., during exercise) and post-cooling strategies when playing tennis in hot dry (HD) and hot humid (HH) conditions. Individual follow-up interviews were also carried on 3 participants to gain an in-depth understanding of the player's experience. Results: Competitive tennis players used both internal and external cooling strategies to combat the negative effects of HD and HH conditions, but considered the HH to be more stressful than HD and experienced more heatrelated illness in HH environments. International players used cold packs and cold towel more frequently than the regional and national players in hot environments, and used cold water immersion and cold vest more frequently than the latter in HH. Differences in strategy use were mostly observed during per-cooling where regional and national players more frequently used cold drinks than international players who more frequently used cold packs in HD and cold towel in HH conditions. Moreover the latter more frequently used cold towel, cold packs and cold water immersion as post-cooling strategies than regional players. Conclusion: When playing tennis in the heat, it is strongly recommended to employ cooling strategies to maintain health, limit declines in performance, and promote recovery. We also recommend improving education regarding the appropriate use and effectiveness of cooling strategies, and increasing their availability in tournaments. [ABSTRACT FROM AUTHOR]

This study aimed to describe and distinguish shot characteristics between set winning and losing pairs in high-level male padel players from Finland. Between 2022 and 2023, we analyzed 4469 points across 38 matches, examining factors such as match type, set outcome, effectiveness of the last shot, generator of forced error, and shot type. Results showed that set-winning players produced more winners (CSR = 7.7; CSR = 6.8) and committed fewer forced (CSR = 4.2; CSR = 2.8) and unforced errors (CSR = 4.0; CSR = 4.3) compared to set losing players, both in pressure training and competition matches. In addition, irrespective of the set outcome, these players achieved more winners and generated more forced errors with the smash, bandeja, forehand volley, and backhand volley. Nevertheless, a significant number of errors (both forced and unforced) are committed with the bandeja and volley (forehand and backhand). Furthermore, notable errors (forced and unforced) are observed in shots following one bounce and without a wall rebound, particularly in the forehand, backhand, and return. In conclusion, the ability to produce winners while minimizing forced and unforced errors proves to be crucial for securing sets in high-level men's padel. [ABSTRACT FROM AUTHOR]

The extensive use of pesticides has led to the contamination of natural resources, sometimes causing significant and irreversible damage to the environment and human health. Even though the use of many pesticides is banned, these compounds are still being found in rivers worldwide. In this review, 205 documents have been selected to provide an overview of pesticide contamination in rivers over the last 10 years (2014–2024). After these documents were examined, information of 47 river systems was organized according to the types of pesticides most frequently detected, including organochloride, organophosphorus, and pyrethroid compounds. A total of 156 compounds were classified, showing that 46% of these rivers contain organochlorine compounds, while 40% exhibit organophosphorus pesticides. Aldrin, hexachlorocyclohexane, and endosulfan were the predominant organochlorine pesticides with concentration values between 0.4 and 37 × 105 ng L−1. Chlorpyrifos, malathion, and diazinon were the main organophosphorus pesticides with concentrations between 1 and 11 × 105 ng L−1. Comparing the pesticide concentrations with standard guidelines, we found that the Ganga River in India (90 ng L−1), the Owan and Okura Rivers in Nigeria (210 and 9 × 103 ng L−1), and the Dong Nai River in Vietnam (68 ng L−1) exceed the permissible levels of aldrin (30 ng L−1). [ABSTRACT FROM AUTHOR]

The combination of metal‐based homogeneous and heterogeneous catalysts in the same reaction media is a powerful, yet relatively unexplored approach in organic chemistry. This strategy can address important limitations associated with purely homogeneous or heterogeneous catalysis such as the incompatibility of different catalytic species in solution, or the limited tunability of solid catalysts, respectively. Moreover, the facile reusability of the solid catalyst, contributes to increase the overall sustainability of the process. As a result, this semi‐heterogeneous multi‐catalytic approach has unlocked significant advances in organic chemistry, improving existing reactions and even enabling the discovery of novel transformations, exemplified by the formal alkane metathesis. This concept article aims to showcase the benefits of this strategy through the exploration of diverse relevant examples from the literature, hoping to spur research on new metal‐based homogeneous‐heterogeneous catalyst combinations that will result in reactivity challenging to achieve by conventional homogeneous or heterogeneous catalysis alone. [ABSTRACT FROM AUTHOR]

IntroductionObservational and modeling studies have examined the interactions between El Niño-Southern Oscillation (ENSO) and the equatorial Atlantic variability as incorporated into the classical charge-recharge oscillator model of ENSO. These studies included the role of the Atlantic in the predictability of ENSO but assumed stationarity in the relationships, i.e., that models’ coefficients do not change over time. A recent work by the authors has challenged the stationarity assumption in the ENSO framework but without considering the equatorial Atlantic influence on ENSO.MethodsThe present paper addresses the changing relationship between ENSO and the Atlantic El Niño using an extended version of the recharge oscillator model. The classical two-variable model of ENSO is extended by adding a linear coupling on the SST anomalies in the equatorial Atlantic. The model’s coefficients are computed for different periods. This calculation is done using two methods to fit the model to the data: (1) the traditional method (ReOsc), and (2) a novel method (ReOsc+) based on fitting the Fisher’s Z transform of the auto and cross-correlation functions.ResultsWe show that, during the 20th century, the characteristic damping rate of the SST and thermocline depth anomalies in the Pacific have decreased in time by a factor of 2 and 3, respectively. Moreover, the damping time of the ENSO fluctuations has doubled from 10 to 20 months, and the oscillation period of ENSO has decreased from 60-70 months before the 1960s to 50 months afterward. These two changes have contributed to enhancing ENSO amplitude. The results also show that correlations between ENSO and the Atlantic SST strengthened after the 70s and the way in which the impact of the equatorial Atlantic is added to the internal ENSO variability.ConclusionsThe remote effects of the equatorial Atlantic on ENSO must be considered in studies of ENSO dynamics and predictability during specific time-periods. Our results provide further insight into the evolution of the ENSO dynamics and its coupling to the equatorial Atlantic, as well as an improved tool to study the coupling of climatic and ecological variables.

The reactive nature of carbenes can be modulated, and ultimately reversed, by receiving additional electron density from a metal. Here, it is shown that Au nanoparticles (NPs) generate an electron-rich carbene on surface after transferring electron density to the carbonyl group of an in situ activated diazoacetate, as assessed by Fourier transformed infrared (FT-IR) spectroscopy, magic angle spinning nuclear magnetic resonance (MAS NMR), and Raman spectroscopy. Density functional theory (DFT) calculations support the observed experimental values and unveil the participation of at least three different Au atoms during carbene stabilization. The surface stabilized carbene shows an extraordinary stability against nucleophiles and reacts with electrophiles to give new products. These findings showcase the ability of catalytic Au NPs to inject electron density in energetically high but symmetrically allowed valence orbitals of sluggish molecules.

Dentro del procesamiento del lenguaje, los recursos lingüísticos son descripciones estructuradas y detalladas de una determinada lengua, esenciales a la hora de estudiar el lenguaje y crear aplicaciones. Sin embargo, estos repositorios son bastantes lentos y difíciles de construir, y además la mayoría de ellos se centra en el inglés. Este trabajo trata de paliar, en cierta medida, el problema de escasez de recursos disponibles en castellano, mediante la traducción al español de las unidades léxicas de los marcos situacionales del proyecto FrameNet, un recurso on-line para el inglés basado en la semántica de marcos. Para ello desarrollamos un procedimiento capaz de asociar los diferentes predicados de cada marco con los synsets de WordNet, una base de datos léxica que organiza el vocabulario según conceptos y relaciones semánticas. Como tendremos oportunidad de comprobar, el sistema alcanza una precisión en torno al 88% y abre la puerta a su uso en estudios lingüísticos de diversa índole en español.

Background: The demands of professional tennis, including physical and psychological aspects, contribute to the frequency of retirements at elite levels of the sport. Purpose: The aim of this study was to explore the frequency of injuries and the factors that influence the retirements of professional tennis players competing in the Davis Cup over the last two decades. Study Design: Retrospective cohort study. Methods: The data set includes data from 6,060 men's singles matches that included 1,814,141 games from Davis Cup ties played between 2000 to 2019. Factors that might influence the retirements were studied by means of generalized linear models using Poisson distribution. Incidence rates by 1000 games and incidence rate ratios of retirements are provided as association measures. Results: The retirement incidence was 1.05 per 1000 games [95% CI: 0.90, 1.21]. The main risk factors associated with retirements were matches played on hard courts (IRR: 2.52 [95% CI: 1.32, 4.83]) and matches played in the final two matches of the tie and in a best-of-5-set format (IRR: 2.63 [95% CI: 1.69, 4.09] and IRR: 5.52 [95% CI: 3.50, 8.69], respectively). The most common injuries that led to retirements were those affecting the lower extremities, specifically involving muscular or tendinous tissues. Conclusion: This study provides valuable insights for coaches, players, support teams, and epidemiologists regarding retirements and their associated risk factors in Davis Cup tournaments. These findings may guide future research and inform strategies aimed at managing player health and performance in professional tennis. Level of evidence: Level 2b. [ABSTRACT FROM AUTHOR]

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