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We have previously designed and synthesized small-molecule inhibitors that reduce Vibrio choleraevirulence in vitroby targeting the transcription factor ToxT. Here we report the synthesis and biological activity of derivatives of our previous bicyclic, fatty acid-like inhibitors. All of the synthesized derivatives show antivirulence activity in vitro.For the most potent compounds, a concentration of 5 μM completely inhibited ToxT-mediated tcpAexpression as measured in the β-galactosidase assay. One indole compound, 3-(1-butyl-1H-indol-7-yl)propanoic acid (8), was also effective at inhibiting intestinal colonization in the infant mouse. These modified compounds may serve as good candidates for further anti-cholera drug development.

We conduct a high‐resolution teleseismic receiver function investigation of the subducting plate interface within the Alaskan forearc beneath Kodiak Island using data collected as part of the Alaska Amphibious Community Seismic Experiment in 2019. The Kodiak node array consisted of 398 nodal geophones deployed at ∼200–300 m spacing on northeastern Kodiak Island within the southern asperity of the 1964 Mw9.2 Great Alaska earthquake. Receiver function images at frequencies of 1.2 and 2.4 Hz show a coherent, slightly dipping velocity increase at ∼30–40 km depth consistent with the expected slab Moho. In contrast to studies within the northern asperity of the 1964 rupture, we find no evidence for a prominent low‐velocity layer above the slab Moho thick enough to be resolved by upgoing P‐to‐S conversions. These results support evidence from seismicity and geodetic strain suggesting that the 1964 rupture connected northern (Kenai) and southern (Kodiak) asperities with different plate interface properties. We use 398 portable seismometers that were deployed as part of the Alaska Amphibious Community Seismic Experiment to image the boundary between the subducting Pacific plate and the base of the North American plate. The seismometers, spaced ∼200–300 m apart, were stationed on Kodiak Island in 2019 within the southern rupture area of the 1964 Mw9.2 Great Alaska earthquake. We analyze conversions from compressional to shear waves from distant earthquakes to understand the conditions of the plate interface. Our results show a dipping velocity increase at ∼30–40 km depth at the expected location of the Pacific slab crust‐mantle boundary. In contrast to prior results from the northern 1964 rupture zone, we do not find a low‐velocity layer on the subducting plate. Our results indicate that the 1964 rupture connected segments of the Alaskan subduction zone with different plate interface properties. We present receiver function imaging from a dense three‐component nodal array deployment on Kodiak Island above the subducting Pacific PlateA clear slab Moho conversion is found but, in contrast to the Kenai Peninsula, there is no coherent low‐velocity layer atop the slabThe 1964 Great Alaska Earthquake ruptured across structural segments with different plate interface properties We present receiver function imaging from a dense three‐component nodal array deployment on Kodiak Island above the subducting Pacific Plate A clear slab Moho conversion is found but, in contrast to the Kenai Peninsula, there is no coherent low‐velocity layer atop the slab The 1964 Great Alaska Earthquake ruptured across structural segments with different plate interface properties

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The North Basin of the Malawi Rift is an active, early‐stage rift segment that provides the opportunity to quantify cumulative and recent faulting patterns in a young rift, assess contributions of intrarift faults to accommodating rift opening, and examine controls on spatial patterns of faulting. Multichannel seismic reflection data acquired in Lake Malawi (Nyasa) in 2015 together with legacy multichannel seismic data image a system of synthetic intrarift faults within this border‐fault‐bounded, half‐graben basin. A dense wide‐angle seismic reflection/refraction dip profile acquired with lake bottom seismometer data constrains sediment velocities that are used to convert fault throws from travel time to depth. Observed extension on intrarift faulting in the northern and central parts of the North Basin is approximately twice what would be predicted for hanging wall flexure, implying that the intrarift faults contribute to basin opening. The cumulative throw on intrarift faults is higher in the northern part of the rift segment than the south and is anticorrelated with throw on the border fault, which is largest in the southern part of the North Basin. This change in faulting coincides with a change in the orientation of the North Basin from a N‐S trend in the south to a NNW‐SSE trend in the north. We infer that the distribution of extension is influenced by rift orientation with respect to the regional extension direction. Almost all intrarift faults substantially offset late Quaternary synrift sediments, suggesting they are likely active and need to be considered in hazard assessments. Intrarift faulting contributes to rift openingThe style and amount of rift faulting change along strike in North BasinNearly all intrarift faults have been active in the last ~75 kyr

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