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ABSTRACT: Numerical modeling of earthquake dynamics and derived insight for seismic hazard relies on credible, reproducible model results. The sequences of earthquakes and aseismic slip (SEAS) initiative has set out to facilitate community code comparisons, and verify and advance the next generation of physics-based earthquake models that reproduce all phases of the seismic cycle. With the goal of advancing SEAS models to robustly incorporate physical and geometrical complexities, here we present code comparison results from two new benchmark problems: BP1-FD considers full elastodynamic effects, and BP3-QD considers dipping fault geometries. Seven and eight modeling groups participated in BP1-FD and BP3-QD, respectively, allowing us to explore these physical ingredients across multiple codes and better understand associated numerical considerations. With new comparison metrics, we find that numerical resolution and computational domain size are critical parameters to obtain matching results. Codes for BP1-FD implement different criteria for switching between quasi-static and dynamic solvers, which require tuning to obtain matching results. In BP3-QD, proper remote boundary conditions consistent with specified rigid body translation are required to obtain matching surface displacements. With these numerical and mathematical issues resolved, we obtain excellent quantitative agreements among codes in earthquake interevent times, event moments, and coseismic slip, with reasonable agreements made in peak slip rates and rupture arrival time. We find that including full inertial effects generates events with larger slip rates and rupture speeds compared to the quasi-dynamic counterpart. For BP3-QD, both dip angle and sense of motion (thrust versus normal faulting) alter ground motion on the hanging and foot walls, and influence event patterns, with some sequences exhibiting similar-size characteristic earthquakes, and others exhibiting different-size events. These findings underscore the importance of considering full elastodynamics and nonvertical dip angles in SEAS models, as both influence short- and long-term earthquake behavior and are relevant to seismic hazard.

This study was conducted to investigate the effect of soymilk fermented by Lactobacillus amylolyticus L6 on intestinal microorganisms and short-chain fatty acids in vitro. After simulated gastrointestinal digestion of the fermented soymilk, the survival rate of L. amylolyticus L6 was determined. Then, the digested product was inoculated with human fecal microorganisms and cultured at 37 ℃ under anaerobic conditions for 48 h, and the changes of short chain fatty acids were determined during the fermentation process. The relative abundance of intestinal flora was analyzed by 16S rRNA sequencing. The results showed that L. amylolyticus L6 in the fermented soymilk maintained a high survival rate after simulated gastrointestinal transport. After 48 h in vitro fermentation with the fermented soymilk, the relative abundance of many harmful intestinal bacteria decreased, and the content of short-chain fatty acids (SCFAs) increased significantly (P < 0.05). These findings suggest that L. amylolyticus L6 fermented soymilk can increase the content of SCFAs after 48 h in vitro fermentation. This study provides a theoretical guidance for the development of fermented soybean products.

Transient receptor potential melastatin 2 (TRPM2) is a calcium-permeable, non-selective cation channel that has an essential role in diverse physiological processes such as core body temperature regulation, immune response and apoptosis.sup.1-4. TRPM2 is polymodal and can be activated by a wide range of stimuli.sup.1-7, including temperature, oxidative stress and NAD.sup.+-related metabolites such as ADP-ribose (ADPR). Its activation results in both Ca.sup.2+ entry across the plasma membrane and Ca.sup.2+ release from lysosomes.sup.8, and has been linked to diseases such as ischaemia-reperfusion injury, bipolar disorder and Alzheimer's disease.sup.9-11. Here we report the cryo-electron microscopy structures of the zebrafish TRPM2 in the apo resting (closed) state and in the ADPR/Ca.sup.2+-bound active (open) state, in which the characteristic NUDT9-H domains hang underneath the MHR1/2 domain. We identify an ADPR-binding site located in the bi-lobed structure of the MHR1/2 domain. Our results provide an insight into the mechanism of activation of the TRPM channel family and define a framework for the development of therapeutic agents to treat neurodegenerative diseases and temperature-related pathological conditions.Structures of the transient receptor potential melastatin 2 channel in the apo resting (closed) state and in the ADP-ribose/Ca.sup.2+-bound active (open) state are determined by cryo-electron microscopy., Author(s): Yihe Huang [sup.1] , Paige A. Winkler [sup.1] , Weinan Sun [sup.2] [sup.3] , Wei Lü [sup.1] , Juan Du [sup.1] Author Affiliations:(1) Van Andel Research Institute, Grand Rapids, [...]

Sparse offshore coverage of seismic networks has hindered detailed studies of submarine earthquakes and their associated seismic hazard. We present results of our analysis of a diver's recording of acoustic signals from an ML = 5.6 earthquake in the Persian Gulf. We model the signals as a set of several shallow water T phases the frequency and group velocity of which are determined by bathymetry. We show that the audio track from this recording can provide reliable estimates of earthquake location and seismic moment. We also show that the reported shaking in the southern Persian Gulf, >170 km from the source of this small earthquake could result from T waves traveling through the entire width of the basin. Our results point to rudimentary and affordable underwater microphones similar to those used in the divers' cameras as tools to build efficient, low‐cost networks for the study of offshore events and early warning. Plain Language Summary: The lack of offshore seismic stations or the low population of such networks has caused our knowledge of near‐shore earthquake sources to be incomplete. To this end, and as a possible tool to study the source of submarine earthquakes, we have analyzed the video recording from a group of divers who have captured the moments during an earthquake in the Persian Gulf region. This earthquake which occurred on the northern, Iranian side of the Persian Gulf was strongly felt along its southern shorelines, more than 170 km from the epicenter. The analysis of this video, which surfaced on social media, points to a set of trapped acoustic signals in the water, or T‐waves, in close proximity of the source. We show that such recordings can be reliably used to obtain important information regarding the earthquake source, including its location and magnitude. Besides, we make the case that the reported shaking in Dubai was likely due to the arrival of such high‐pitch T‐ waves from the earthquake. Finally, we propose that cheap microphones existing in standard entertainment cameras can be used to build efficient underwater networks for monitoring small to moderate offshore events. Key Points: We use a diver's camera recording to study an offshore, moderate earthquake in the Persian GulfA propagation model and simulations of shallow water T‐waves are presentedLow‐cost, entertainment‐quality, subsea hydrophones run by citizen scientists can augment monitoring of offshore events [ABSTRACT FROM AUTHOR]