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Adaptive radiation plays a fundamental role in our understanding of the evolutionary process. However, the concept has provoked strong and differing opinions concerning its definition and nature among researchers studying a wide diversity of systems. Here, we take a broad view of what constitutes an adaptive radiation, and seek to find commonalities among disparate examples, ranging from plants to invertebrate and vertebrate animals, and remote islands to lakes and continents, to better understand processes shared across adaptive radiations. We surveyed many groups to evaluate factors considered important in a large variety of species radiations. In each of these studies, ecological opportunity of some form is identified as a prerequisite for adaptive radiation. However, evolvability, which can be enhanced by hybridization between distantly related species, may play a role in seeding entire radiations. Within radiations, the processes that lead to speciation depend largely on (1) whether the primary drivers of ecological shifts are (a) external to the membership of the radiation itself (mostly divergent or disruptive ecological selection) or (b) due to competition within the radiation membership (interactions among members) subsequent to reproductive isolation in similar environments, and (2) the extent and timing of admixture. These differences translate into different patterns of species accumulation and subsequent patterns of diversity across an adaptive radiation. Adaptive radiations occur in an extraordinary diversity of different ways, and continue to provide rich data for a better understanding of the diversification of life.

Adaptive radiation plays a fundamental role in our understanding of the evolutionary process. However, the concept has provoked strong and differing opinions concerning its definition and nature among researchers studying a wide diversity of systems. Here, we take a broad view of what constitutes an adaptive radiation, and seek to find commonalities among disparate examples, ranging from plants to invertebrate and vertebrate animals, and remote islands to lakes and continents, to better understand processes shared across adaptive radiations. We surveyed many groups to evaluate factors considered important in a large variety of species radiations. In each of these studies, ecological opportunity of some form is identified as a prerequisite for adaptive radiation. However, evolvability, which can be enhanced by hybridization between distantly related species, may play a role in seeding entire radiations. Within radiations, the processes that lead to speciation depend largely on (1) whether the primary drivers of ecological shifts are (a) external to the membership of the radiation itself (mostly divergent or disruptive ecological selection) or (b) due to competition within the radiation membership (interactions among members) subsequent to reproductive isolation in similar environments, and (2) the extent and timing of admixture. These differences translate into different patterns of species accumulation and subsequent patterns of diversity across an adaptive radiation. Adaptive radiations occur in an extraordinary diversity of different ways, and continue to provide rich data for a better understanding of the diversification of life.

While football/soccer is the most influential sport in the world, it is surprising that developmental sequences of forceful kicking have not been adequately described and validated in the literature. The purpose of this study was to explore potential developmental sequences for forceful kicking using a prelongitudinal screening method. Data were derived from videotapes of 255 children (girls n = 138, boys: n = 117), ages 4-11 years. Seven potential component sequences in their respective developmental order were initially proposed based on biomechanical and motor developmental principles. Each participant was digitally videoed performing five kicks with maximal effort. Trained research staff coded the initial seven components for each kick and the mode of each participant's five kicks was used for data analysis. Component level probability curves for each component sequence across age were evaluated using the threshold based generalized partial credit model (Muraki, 1992) within the item response theory framework. As developmental theory would indicate, component levels generally increased with age for most components. Six component ordinal sequence progressions met model requirements (Rel = 0.88, item fit; p > 0.05). Ordinal levels for two components ("Knee action" and "Follow-through") were altered based on initial empirical model structure fit and the Ball contact component was removed based on a lack of model fit. This study provides sufficient cross-sectional evidence for six component developmental sequences that adequately describe the development of kicking using cross-sectional data. Longitudinal data are required to provide further developmental validation for these sequences.

Copper joints are indispensable in electronics and the electrical power industry due to their predominant usage in battery pack manufacturing for electric vehicle). Traditional joining methods are often limited by oxidation-related challenges. Recent efforts have focused on addressing these limitations by employing solid-state techniques like ultrasonic welding (USW) for joining similar metals. USW presents attractive advantages such as a lower processing temperature and shorter weld time. This study investigates the ultrasonic welding of Cu-Cu joints with a thickness of 0.5 mm, focusing on both mechanical and metallurgical properties. The influence of key process parameters, such as the welding time, pressure and vibration amplitude, was examined in relation to the welding energy and lap shear strength. Additionally, the relationship between the input energy and lap shear strength was explored. A Pareto chart analysis revealed the standardized effects of these parameters on the welding energy and average lap shear strength. The welding time had a significant influence on the welding energy, while the vibration amplitude had the greatest impact on the joint strength. Longer weld times of 2.50 to 4 s yielded a higher lap shear strength, averaging up to 2.30 kN. Notably, a higher lap shear strength was achieved at lower welding energy levels. [ABSTRACT FROM AUTHOR]

This review provides an overview of the existing literature on school-aged children's and youth's (i.e. 6- to 18-year-olds) personal and social development within the context of physical education and sports. A total of 4359 non-duplicate articles were retrieved from six databases. After the title, abstract and full text screening, 88 articles met the inclusion criteria and were included for further analysis. Articles had to be published in a peer-reviewed journal between 1 January 2008 and 6 December 2017. The 88 studies used several study designs, methods and instruments to investigate a variety of concepts related to personal and social development. Concepts were grouped into the following 11 themes: work ethic; control and management; goal-setting; decision-making; problem-solving; responsibility; leadership; cooperation; meeting people and making friends; communication; and prosocial behaviour. The main findings for each of the 11 themes are reported, and limitations and implications are provided to guide researchers and practitioners in their future work.