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The Hayward fault in California's San Francisco Bay area produces large earthquakes, with the last occurring in 1868. We examine how physics‐based dynamic rupture modeling can be used to numerically simulate large earthquakes on not only the Hayward fault, but also its connected companions to the north and south, the Rodgers Creek and Calaveras faults. Equipped with a wealth of images of this fault system, including those of its 3D geology and 3D geometry, in addition to inferences about its interseismic creep‐rate pattern and rock‐friction behavior, we use a finite‐element computer code to perform 3D dynamic earthquake rupture simulations. We find that the rock properties affect the locations and amount of slip produced in our simulated large earthquakes. Crucial factors that control rupture behavior in our modeling are the earthquake nucleation locations, the fault geometry, and the data that reveal where the fault system is creeping or locked. Our findings suggest that large Rodgers Creek‐Hayward‐Calaveras‐Northern Calaveras (RC‐H‐C‐NC) fault‐system earthquakes may result from dynamic rupture that starts in a locked part of the fault system, but is then stopped by the creeping parts, leading to high‐magnitude‐6 earthquakes; or, from dynamic rupture that starts in a locked part of the fault system, then cascades through some of the creeping parts, leading to magnitude‐7 earthquakes. Plain Language Summary: The San Francisco Bay area has experienced large earthquakes in the past and is likely to experience large earthquakes in the future. Although the San Andreas fault is the best‐known earthquake generator, other San Francisco Bay area faults, including some that slowly move (creep) all of the time are also known to be hazardous. We use computer modeling to simulate large earthquakes on the Hayward fault, and its connected companions to the north and south, the Rodgers Creek and Calaveras faults. In our computer simulations, we include information about the rock properties, rock‐friction, and fault geometry, in addition to inferences about where the faults creep. We find that the earthquake nucleation location, the fault geometry, and the pattern of fault creep, are most important. Our findings suggest that large earthquakes on these faults may result from a fast‐slipping rupture that starts in a locked part of the faults, but is then stopped by the slowly slipping parts of the faults, leading to high‐magnitude‐6 earthquakes, or, from fast‐slipping rupture that starts in a locked part of the faults, then cascades through some of the creeping‐fault parts, leading to magnitude‐7 earthquakes. Key Points: We simulated large earthquakes on the Rodgers Creek‐Hayward‐Calaveras fault system, CaliforniaOur spontaneous rupture (dynamic rupture) simulations included the 3D fault geometry, 3D rock properties, and creeping‐fault patchesThe resulting earthquakes are most affected by which fault they start on, the fault geometry, and the pattern of interseismic fault creep [ABSTRACT FROM AUTHOR]

Streptococcus mutans resides in the oral polymicrobial biofilm and is a major contributor to the development of dental caries. Interestingly, high salivary nitrite concentrations have been associated with a decreased prevalence of dental caries. Moreover, the combination of hydrogen peroxide-producing oral commensal streptococci and nitrite has been shown to mediate the generation of reactive nitrogen species, which have antimicrobial activity. The goal of this study was to examine whether nitrite affects S. mutans virulence during polymicrobial infections with the commensal Streptococcus parasanguinis. Here, we report that the combination of S. parasanguinis and nitrite inhibited S. mutans growth and biofilm formation in vitro. Glucan production, which is critical for S. mutans biofilm formation, was also inhibited in 2-species biofilms with S. parasanguinis containing nitrite as compared with biofilms that contained no nitrite. In the in vivo caries model, enamel and dentin carious lesions were significantly reduced in rats that were colonized with S. parasanguinis prior to infection with S. mutans and received nitrite in the drinking water, as compared with animals that had a single S. mutans infection or were co-colonized with both bacteria and received no nitrite. Last, we report that S. mutans LiaS, a sensor kinase of the LiaFSR 3-component system, mediates resistance to nitrosative stress. In summary, our data demonstrate that commensal streptococci and nitrite provide protection against S. mutans pathogenesis. Modulating nitrite concentrations in the oral cavity could be a useful strategy to combat the prevalence of dental caries. [ABSTRACT FROM AUTHOR]

Dental caries is a costly and prevalent disease characterized by the demineralization of the tooth's enamel. Disease outcome is influenced by host factors, dietary intake, cariogenic bacteria, and other microbes. The cariogenic bacterial species Streptococcus mutans metabolizes sucrose to initiate biofilm formation on the tooth surface and consequently produces lactic acid to degrade the tooth's enamel. Persistence of S. mutans biofilms in the oral cavity can lead to tooth decay. To date, no anticaries therapies that specifically target S. mutans biofilms but do not disturb the overall oral microbiome are available. We screened a library of 2-aminoimidazole antibiofilm compounds with a biofilm dispersion assay and identified a small molecule that specifically targets S. mutans biofilms. At 5 µM, the small molecule annotated 3F1 dispersed 50% of the established S. mutans biofilm but did not disperse biofilms formed by the commensal species Streptococcus sanguinis or Streptococcus gordonii. 3F1 dispersed S. mutans biofilms independently of biofilm-related factors such as antigen I/II and glucosyltransferases. 3F1 treatment effectively prevented dental caries by controlling S. mutans in a rat caries model without perturbing the oral microbiota. Our study demonstrates that selective targeting of S. mutans biofilms by 3F1 was able to effectively reduce dental caries in vivo without affecting the overall oral microbiota shaped by the intake of dietary sugars, suggesting that the pathogenic biofilm-specific treatment is a viable strategy for disease prevention. [ABSTRACT FROM AUTHOR]

Layered composite electro-ceramics can be designed to exhibit the magnetoelectric (ME) effect based on stress transfer from magnetostriction of ferromagnetic layer to the ferroelectric layer. Many studies in search of giant ME coefficients in layered composites have been made but there are less studies regarding the ME effect in these ceramic materials as a function of temperature, mainly at low temperatures. With the influential increase in magnetoelectric sensing devices use in extreme, minute or precise field monitoring, a broadband temperature dependent analysis on ME effect of these sensors is much required. In this work the effect of temperature on ME effect in a NiFe2O4/Pb(Zr0.52Ti0.48)O3/NiFe2O4layered composite are studied and any major/minute change have been analyzed. Dynamic ME measurements shows a maximum linear ME coefficient (αME= 238 mV/cm.Oe) by applying an AC magnetic field in a frequency of 600 Hz at room. Highly reduced αMEvalues are observed at low temperatures. Magnetocapacitance effect studies showed a strong magnetoelectric coupling at room temperature and, also, a dramatic reduction in the magnetoelectric coupling at 200 K and 100 K. Analyzing the phenomena mathematically shows that there is a secondary effect interaction which influences the ME effect intensity depending on temperature. [ABSTRACT FROM AUTHOR]

Chapter 27 of the ancient Chinese text the Zhuangzi (c. 400 BCE) describes three kinds of language: yuyan, zhiyan, and chongyan. WangFuzhi(1619-1692) first coined the term 'sanyan' or 'tripartite-language' to emphasize their overlapping characteristics and incorporate them into a cohesive approach to the text. Sanyan has been used consistently in interpreting the Zhuangzi since the earliest compilation of its extant version and continues to inform academic publications today. Based on descriptions found in the Zhuangzi's 'miscellaneous chapters' (chapters 23-33) and on contemporary scholarship, I will explain how this model of sanyan functions and then how it facilitates philosophical reading of the Zhuangzi. Understanding the Zhuangzi's metaphorical language through sanyan lends access into the interrelated semantic field of the pre-Qin philosophical canon and helps unravel Zhuangzi's often-cryptic philosophical expressions. [ABSTRACT FROM AUTHOR]