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The present study aimed to examine the relationship between coach dismissal and team performance, and match physical demands in the top two professional Spanish soccer leagues across both short and long term within a season. Data were collected from all matches played in the First (Liga Santander; n = 2,950) and Second Spanish Division (Liga Smartbank; n = 2,966) over four consecutive seasons (from 2015/2016 to 2018/2019). Team performance (points won), total distance (TD), high-intensity running distance (HIRD, distance 21–24 km⋅h−1), very-high-intensity running distance (VHIRD, >24 km⋅h−1) and the number of efforts between 21–24 km⋅h−1 (Sp21) and >24 km⋅h−1 (Sp24) were analysed. All within-season coaching dismissals were examined. Results showed that team performance was significantly higher after coach dismissal across short term (p <.001). Concerning match physical demands, across the short term, only TD was significantly greater after coach dismissal (p <.01); while across long terms, TD, HIRD, VHIRD, Sp21 and Sp24 were significantly greater during post coach dismissal stage (p <.001) than the prior coach dismissal stage. Such findings demonstrate that coach replacement could positively influence on team performance and match physical demands, not only across the short term but also over the season. [ABSTRACT FROM AUTHOR]

This research analysed the influence of lockdown and interruption of competitions due to COVID-19 on different ball possession-related variables. Also, match location and the differences between divisions were considering between the pre- and post-lockdown. A total of 144,689 records from 842 soccer matches during the 2019/20 season of the First (n = 380) and Second Spanish Division (n = 462) were collected. Match data were collected using the ChryonHego video-tracking system. Pre-lockdown (1st–27th matchday in First Division and 1st–31st matchday in Second Spanish Division) and post-lockdown periods (28th–38th matchday in First Division and 32nd–42nd matchday in Second Spanish Division) were compared. The match location contextual-related variable was also considered for the analysis. Linear mixed models showed that the number of outplayed players by ball possession (3.1%), successful passes (17.5%) and total passes (18.9%) increased during the post-lockdown period (p <.001). In addition, match location and league significantly influenced the successful and total passes in all situations (p <.001), increasing in the post-lockdown period. In conclusion, the lockdown period has led changes in the ball possession of the soccer teams. These results help to understand the impact that a particular and unusual situation as the interruption of the league due to COVID-19 lockdown had on the performance of professional soccer teams. [ABSTRACT FROM AUTHOR]

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The beneficial effects of n–3 polyunsaturated fatty acids (PUFA) are well known, but their consumption in western countries is chronically insufficient, and so it is recommended that diets should be supplemented with a fat rich in these fatty acids. However, the effect of such diets on the energy expenditure remains a controversial question. Precise data concerning the effect of using under the same metabolizable energy intake, a diet non-supplemented or supplemented with a fat rich in n–3 PUFA are not available. This type of information was obtained using rats at weaning fed a diet supplemented or non-supplemented with 10% of fish oil. Between the 30th and 60th day after starting the experiment, the energy and protein balance was established by means of the comparative slaughter method. The blood levels of different metabolites were also determined. Although total thermogenesis did not vary between the two groups, consumption of the fish oil diet led to a lower level of thermogenesis associated with the oxidation of protein, and a higher one of that associated with the oxidation of fat. We conclude that the thermic effect of feeding is a combination of independent processes. Due to their specific metabolism, n–3 PUFA may be considered essential compounds to maintain the energy balance. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Incorporation of silver ions into undoped and doped lead crystal glass was performed by ion exchange. Polyvalent arsenic, antimony, cerium and tin oxides, used as thermoreducing agents, were added in different weight percentages to the starting lead crystal glass. Thus, several doped lead crystal glasses were obtained by conventional melting. The role of the polyvalent oxides as reducing agents of silver ions introduced by ion exchange was studied by focussing on analysis of diffusion depth profiles obtained by SEM-EDX and direct observations performed by TEM. The optical absorption behaviour of the samples was studied to clarify the influence of the parameters involved in the ion exchange process. Chromatic coordinates were calculated from the corresponding transmission visible spectra. The influence of the nature and concentration of the polyvalent oxide dopants on the formation, size and aggregation of silver colloids is discussed Experimental parameters affecting the ion exchange treatment were varied and optimised to obtain silver colloids suitable to produce yellow and red ruby colouring in the undoped and doped lead crystal glasses, respectively. The most intense red ruby colouring was obtained with antimony doped lead crystal glasses, which were the most efficient at reducing silver ions and forming nanosized metallic colloids. Temperature, silver nitrate concentration in the molten salt bath and duration of the ion exchange treatment affect the size, aggregation and distribution of the silver colloids generated It has been demonstrated that ion exchange is a suitable process to obtain superficial ruby lead crystal glasses. In such glasses the synergic presence of both silver and a polyvalent oxide dopant favours the formation of metallic particles responsible for the ruby colouring. [ABSTRACT FROM AUTHOR]