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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]

The conservation and utilization of cultural heritage resources play a crucial role in the sustainable development of regional tourism in mountainous multi-ethnic areas. Nevertheless, these heritage resources tend to be numerous and geographically dispersed, poorly accessible, and difficult to preserve and utilize, which makes utilizing them holistically at a regional level challenging. Furthermore, each cultural heritage has a specific capacity for cultural dissemination, and establishing the links between heritage sites can enhance the overall cultural influence of a region and promote the development of regional tourism. Consequently, this study aims to promote the conservation and utilization of cultural heritage by constructing a cultural landscape tourism corridor network in the region. A potential cultural landscape tourism corridor network was first constructed based on the least-cost path analysis. Then, the layout and hierarchy of the potential network were optimized based on the existing traffic layout in the area. Finally, for mountainous multi-ethnic areas with poor access to transportation, the tourism corridor network may support the holistic conservation and use of the region's cultural heritage and the development of regional cultural tourism. [ABSTRACT FROM AUTHOR]

Ligand molecules naturally constitute a graph structure. Recently, many excellent deep graph learning (DGL) methods have been proposed and used to model ligand bioactivities, which is critical for the virtual screening of drug hits from compound databases in interest. However, pharmacists can find that these well-trained DGL models usually are hard to achieve satisfying performance in real scenarios for virtual screening of drug candidates. The main challenges involve that the datasets for training models were small-sized and biased, and the inner active cliff cases would worsen model performance. These challenges would cause predictors to overfit the training data and have poor generalization in real virtual screening scenarios. Thus, we proposed a novel algorithm named adversarial feature subspace enhancement (AFSE). AFSE dynamically generates abundant representations in new feature subspace via bi-directional adversarial learning, and then minimizes the maximum loss of molecular divergence and bioactivity to ensure local smoothness of model outputs and significantly enhance the generalization of DGL models in predicting ligand bioactivities. Benchmark tests were implemented on seven state-of-the-art open-source DGL models with the potential of modeling ligand bioactivities, and precisely evaluated by multiple criteria. The results indicate that, on almost all 33 GPCRs datasets and seven DGL models, AFSE greatly improved their enhancement factor (top-10%, 20% and 30%), which is the most important evaluation in virtual screening of hits from compound databases, while ensuring the superior performance on RMSE and |$r^2$|⁠. The web server of AFSE is freely available at http://noveldelta.com/AFSE for academic purposes. [ABSTRACT FROM AUTHOR]

Tsunamis from earthquakes of various magnitudes have affected Cascadia in the past. Simulations of Mw 7.5–9.2 earthquake constrained by earthquake rupture physics and geodetic locking models show that Mw ≥ 8.5 events initiating in the middle segments of the subduction zone can create coastal tsunami amplitudes comparable to those from the largest expected event. Our rupture and tsunami simulations reveal that the concave coastline geometry of the Pacific Northwest coastline focuses tsunami energy between latitudes 44° and 45° in Oregon. The possible coastal tsunami amplitudes are largely insensitive to the choice of slip model for a given magnitude. These results are useful for identifying the most hazardous segments of the subduction zone and demonstrate that a worst‐case rupture scenario does not uniquely yield the worst‐case tsunami scenario at a given location. Plain Language Summary: Offshore earthquakes along the Pacific Northwest coast of the U.S. and Canada (Cascadia region) can have magnitudes as high as 9.2, as was probably the case for an earthquake in the year 1700 CE that resulted in a large tsunami in Cascadia and across the Pacific Ocean. To learn more about the future tsunami hazard in the region, we design computer models of tsunamis from a wide range of earthquake scenarios. We find that almost regardless of the earthquake source details, events larger than magnitude 8.5 near the coast of Oregon can create large and widespread tsunamis along the US west coast. These are consequences of the geometry of offshore earthquake faulting and the concave shape of coastline in the region. Key Points: A Mw = 8.5 event in central Cascadia (Oregon) can create coastal tsunami amplitudes comparable to those from the largest possible eventThe concave coastline contributes to larger coastal tsunami amplitudes in central CascadiaThe choice of slip model does not significantly affect the distribution of coastal tsunami amplitudes in Cascadia [ABSTRACT FROM AUTHOR]