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Large earthquakes can trigger smaller seismic events, even at significant distances. The process of earthquake triggering offers valuable insights into the evolution of local stress states, deepening our understanding of the mechanisms of earthquake nucleation. However, our ability to detect these triggered events is limited by the quality and spatial density of local seismometers, posing significant challenges if the triggered event is hidden in the signal of a nearby larger earthquake. Distributed acoustic sensing (DAS) has the potential to enhance the monitoring capability of triggered earthquakes through its high spatial sampling and large spatial coverage. Here, we report on an uncatalogued magnitude (M) 5.1 event in northeast Turkey, which was likely dynamically and instantaneously triggered by the 2023 M7.8 earthquake in southeast Turkey, located 400 km away. This event was initially discovered on ∼1,100 km of active DAS recordings that are part of an 1,850‐km linear array. Subsequent validation using local seismometers confirmed the event's precise time, location, and magnitude. Interestingly, this dynamically triggered event exhibited precursory signals preceding its P arrivals on the nearby seismometers. It can be interpreted as the signal from other nearby, uncatalogued, smaller triggered events. Our results highlight the potential of high‐spatial‐density DAS in enhancing the local‐scale detection and the detailed analysis of earthquake triggering. Large earthquakes can trigger smaller ones even far away. This helps us understand more about how earthquakes start and develop. However, finding these smaller earthquakes can be difficult as sometimes they are hidden in the chaos of a bigger, nearby earthquake. There is a novel technology called Distributed Acoustic Sensing (DAS) that might help. DAS can listen for earthquakes over large areas and gives a more detailed picture of what's happening underground. In this study, we discovered a moderate‐size earthquake with a magnitude of 5.1 in Northeast Turkey that was triggered by a large earthquake with a magnitude of 7.8 in Southeast Turkey, using a DAS system that stretched over a thousand kilometers. We then checked this finding with conventional seismometers to be sure. Interestingly, this triggered earthquake showed precursory signals before its main shaking started, which could be signs of other smaller earthquakes happening nearby. Our findings deepen our understanding of how earthquakes interact with each other and offer insights into how earthquakes start. Our results also suggest that DAS could help us find and understand these triggered earthquakes, providing us with invaluable information for future seismology studies. We find an uncatalogued M5.1 earthquake in NE Turkey dynamically and instantaneously triggered by the 2023 Mw 7.8 SE Turkey earthquakeWe uncover this event on a thousand‐kilometer linear distributed acoustic sensing array, then confirm its precise time, location, and magnitude with seismometersPrecursory signals of the M5.1 event are observed and are most likely resulting from other nearby events rather than its nucleation phase We find an uncatalogued M5.1 earthquake in NE Turkey dynamically and instantaneously triggered by the 2023 Mw 7.8 SE Turkey earthquake We uncover this event on a thousand‐kilometer linear distributed acoustic sensing array, then confirm its precise time, location, and magnitude with seismometers Precursory signals of the M5.1 event are observed and are most likely resulting from other nearby events rather than its nucleation phase

Some exact solutions for the small-first-order perturbations of an FRW metric minimally coupled to a neutral massive scalar field are presented.

Faecal specimens were collected from infants and children with common infections who presented to the Paediatrics Outpatient Department of the National Children's Hospital, San Jose, Costa Rica or to the Paediatrics Clinic, Texas Tech University Health Sciences Center, Lubbock, Texas. Specimens were obtained before administration of various antibiotics, 7 d after therapy was begun and 28 d after completion of treatment. The antibiotics prescribed were either amoxicillin, ampicillin, cephalexin, choramphenicol, dicloxocillin, erythromycin, penicillin or trimethroprim/ sulphamethoxazole. Faecal concentrations of total and individual volatile fatty acids (VFA) and faecal pH levels were determined and compared before, during and after treatment with the various antibiotics. Specimens, collected during the same time periods from a group of healthy infants and children who were not taking antibiotics, were evaluated to determine if normal fluctuations occurred between samplings. There were no significant differences in the Texas subjects in total VFA concentrations and pH levels between the patients receiving antibiotics and healthy participants who did not. With the exception of erythromycin administered to Costa Rican patients, therapeutic doses of the antibiotics did not significantly alter total VFA concentrations or pH levels of the faeces. Variations in concentrations of individual VFAs as a consequence of treatment were demonstrated only in Costa Rican patients receiving either erythromycin or cephalexin; however, the patterns of change were similar to those observed in untreated control participants from Texas and were therefore not attibuted to antibiotic administration. These results are in accordance with our previous studies which show that absorbable antibiotics, administered to mice in therapeutic doses, do not significantly alter total VFA concentrations or pH levels of caecal contents and do not increase the susceptibility of the animals to oral challenge with enteric pathogens.10 We speculate that the use of absorbable antibiotics does not compromise natural resistance against infections of the intestinal tract of humans.