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IntroductionThe irrational use of antibiotics has facilitated the emergence of multidrug- resistant Shigella spp., undermining the effectiveness of the currently available antibiotics. Consequently, there is an urgent need to explore new approaches, with phage therapy emerging as a promising alternative.MethodsIn this study, we isolated a phage targeting Shigella dysenteriae from sewage samples using DLA methold, designated Henu10. The morphology, biological characteristics, genomic composition, and phylogenetic relationships of Henu10 were thoroughly characterized. To investigate the trade-off relationship between phage resistance and bacterial fitness, phage Henu10-resistant strains R6 and R11 were identified using continuous passage and bidirectional validation methods.ResultsPhage-resistant strains R6 and R11 exhibited impaired adsorption, increased sensitivity to temperature and pH stress, heightened susceptibility to certain antibiotics (such as ciprofloxacin and kanamycin), reduced biofilm-forming capacity, and diminished colonization ability in vivo compared to the wild-type strain.DiscussionThese results indicate that phage Henu10 may effectively control the pathogenic bacteria associated with S. dysenteriae, representing a promising new therapeutic option for treating S. dysenteriae infections.

The collision and friction between the rock masses during the caving of the gob roof has become an important hidden danger to induce the gas explosion accident in the gob. In order to study the mechanism of gas explosion induced by sandstone friction by friction velocity, friction force, gas concentration, SiO2 content and other factors, the rock friction effect igniting gas test system was used to conduct quantitative test research on each factor. The results show that when the gas concentration is 7.0%-11.5%, the gas explosion time induced by sandstone friction first decreases and then increases with the increase of gas concentration. The high friction and hot surface of sandstone is the main cause of gas explosion. Gas explosion induced by friction can be divided into two stages: gas burning on sandstone friction surface and gas explosion diffusion. The time of gas explosion induced by friction decreases with the increase of friction and the increase of SiO2 content in sandstone. When the friction is lower than the minimum critical velocity, the gas explosion will not be induced. When the friction is higher than the minimum critical velocity and lower than the maximum critical velocity, the maximum friction velocity is negatively correlated with the gas explosion time.