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The red swamp crayfish (Procambarus clarkii) is the most widely spread freshwater crayfish worldwide. Competing physiological traits can influence invasion success in any given environment by limiting the available scope for aerobically demanding activities. While high flows have been associated with reduced crayfish movement upstream, the effects of flow alteration on their metabolic demands have been largely overlooked. In this study, we estimated routine metabolic rate (RMR) at rest and oxygen consumption rates of crayfish under different current velocities in a flume respirometer, while maximum metabolic rate (MMR) was determined using the exhaustive chase protocol. We also measured some morphometric variables in males and females of crayfish. Oxygen uptake substantially increased with crayfish size and current velocity due to increased energy expenditure to overcome drag and hold a stationary position. Sexual dimorphism in morphological traits did not lead to sexual differences in oxygen uptake. Moreover, we found that individuals operated close to their maximum aerobic capacity at elevated current velocities (≥ 25 cm s−1). This suggested that the high flow-driven energetic demand may compromise the energy available for reproduction, growth and dispersal, thereby affecting overall fitness. These metabolic constraints could partly explain the failed invasions of invasive crayfish in fast-flowing waters. [ABSTRACT FROM AUTHOR]

The application of Teaching Games for Understanding (TGfU) and Game Centered Approaches (GCA) in team sports initiation generated the need for assessing game performance. In this paper we introduce the Rugby Attack Assessment Instrument (RAAI), a tool to assess the actions of players in attack and their incidence in the generated game situations in rugby. The RAAI focuses the attention on the ball carrier during a 5 vs. 5 situation. The actions of players in possession of the ball are described and codified. A weight is allocated to each simple and combined action in relation to its tactical value. Thus, the codified actions provide a weighted Index of Performance, the team score of the RAAI. Validity and reliability were tested in two different studies. Results suggest that the RAAI is valid and reliable to assess ball carrier's actions and their influence in attacking game situations of novice rugby union players. [ABSTRACT FROM AUTHOR]

Apocrine cystomatosis is a rare condition characterized by clusters of cystically dilated sweat glands or other specialized apocrine glands. Cystic dilation of cutaneous sweat glands has been described in humans, dogs, and cats, but not in pigs, to our knowledge. We describe herein linear, brown, colloid-filled cavities < 1 cm diameter within the subcutaneous fat of the entire dorsal region of carcasses of three 6-mo-old pigs. These incidental findings were detected during meat inspection in 3 different slaughterhouses in Catalonia, Spain. Histopathology revealed multiple cystic cavities lined by flattened glandular epithelium, filled with proteinaceous material, and corresponding to cystic hyperplasia of sweat glands. [ABSTRACT FROM AUTHOR]

Background:The social constructivist perspective emphasises that learning is a process of self-construction of knowledge in a social context. Game-centred approaches, such as teaching games for understanding, have been used in accordance with this perspective. The process of transferring learning responsibility takes place when the learner is building his/her own knowledge. Purpose:the aim of this paper is to explore how progressively transferring responsibility for learning from the coach to the players occurs in an ecological learning environment. We address it describing the joint activity organisation and its dynamic evolution for a coaching sequence of rugby through the analysis of interaction between the players and the coach. Participants and setting:Ten novice rugby players (aged 17–19) and a coach-researcher participated in this study. The study was conducted over a 6-week period with a total of 11 sessions, each of 90 minutes. Research design:the research was designed as participant observation in a unique case study based on the observation of an ecological learning environment in a rugby club. Data collection:We video- and audio-recorded the sessions. Transcripts of sessions, including all verbal exchanges and descriptions of participants’ motor performance, are the main source of data. Data analysis:The unit of analysis is the segment of interactivity (SI). This is defined as the period of time within a session in which verbal exchanges and specific behaviours by participants are under the same instructional function. SIs are identified by analysis of interactivity that is generated during the learning process; they are not given in advance. In this study we analyse the evolution of the identified SIs during the 11-lesson unit in an interactivity map. The map depicts changes that occur during the learning process in relation to the transfer of learning responsibility from the coach to the players. Results:we have identified six SIs: SI Activity Organisation, SI Guided Practice, SI Autonomous Practice, SI Discussion, SI Recapitulation and SI Transition. There was an evolution of these SIs over the course of the unit showing transfer of learning control from coach to learner. This was evident by a decrease in SIs Activity Organisation in conjunction with an increase in SIs of Guided and Autonomous Practice. We also show that reflection time is firstly organised around specific SI Discussion, but progressively transferred to reflection during the guided practice, mainly about tactical aspects. Conclusions:In consonance with other research conducted in naturalistic physical education and sports contexts, we observe that the learning transfer process occurs but is neither linear nor progressive. We obtained specific evidences of this process, although we find abrupt changes in the shape of breakdowns and disruptions that make this process partially unpredictable. The consistent situations of discussion and reflection that appear in the SIs Discussion, Recapitulation and Guided Practice seem to play an important role that facilitates game understanding of learners. We consider the analysis of real teaching and learning settings to be of paramount importance to understand the educational influence that emerges in the knowledge construction in sports pedagogy. [ABSTRACT FROM PUBLISHER]