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The aim was to use a combination of video analysis and microtechnology (10 Hz global positioning system [GPS]) to quantify and compare the speed and acceleration of ball-carriers and tacklers during the pre-contact phase (contact − 0.5s) of the tackle event during rugby league match-play. Data were collected from 44 professional male rugby league players from two Super League clubs across two competitive matches. Tackle events were coded and subject to three stages of inclusion criteria to identify front-on tackles. 10 Hz GPS data was synchronised with video to extract the speed and acceleration of the ball-carrier and tackler into each front-on tackle (n = 214). Linear mixed effects models (effect size [ES], confidence intervals, p-values) compared differences. Overall, ball-carriers (4.73 ± 1.12 m∙s−1) had greater speed into front-on tackles than tacklers (2.82 ± 1.07 m∙s−1; ES = 1.69). Ball-carriers accelerated (0.67 ± 1.01 m∙s−2) into contact whilst tacklers decelerated (−1.26 ± 1.36 m∙s−2; ES = 1.74). Positional comparisons showed speed was greater during back vs. back (ES = 0.66) and back vs. forward (ES = 0.40) than forward vs. forward tackle events. Findings can be used to inform strategies to improve performance and player welfare. [ABSTRACT FROM AUTHOR]

Bacterial antimicrobial resistance (AMR) is among the most significant challenges to current human society. Exposing bacteria to antibiotics can activate their self- saving responses, e.g., filamentation, leading to the development of bacterial AMR. Understanding the molecular changes during the self- saving responses can reveal new inhibition methods of drug- resistant bacteria. Herein, we used an online microfluidics mass spectrometry system for real- time characterization of metabolic changes of bacteria during filamentation under the stimulus of antibiotics. Significant pathways, e.g., nucleotide metabolism and coenzyme A biosynthesis, correlated to the filamentation of extended- spectrum beta- lactamase- producing Escherichia coli (ESBL- E. coli) were identified. A cyclic dinucleotide, c- di- GMP, which is derived from nucleotide metabolism and reported closely related to bacterial resistance and tolerance, was observed significantly up- regulated during the bacterial filamentation. By using a chemical inhibitor, ebselen, to inhibit diguanylate cyclases which catalyzes the synthesis of c- di- GMP, the minimum inhibitory concentration of ceftriaxone against ESBL- E. coli was significantly decreased. This inhibitory effect was also verified with other ESBL- E. coli strains and other beta- lactam antibiotics, i.e., ampicillin. A mutant strain of ESBL- E. coli by knocking out the dgcM gene was used to demonstrate that the inhibition of the antibiotic resistance to beta- lactams by ebselen was mediated through the inhibition of the diguanylate cyclase DgcM and the modulation of c- di- GMP levels. Our study uncovers the molecular changes during bacterial filamentation and proposes a method to inhibit antibiotic- resistant bacteria by combining traditional antibiotics and chemical inhibitors against the enzymes involved in bacterial self- saving responses. [ABSTRACT FROM AUTHOR]