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1. An Elementary Derivation of the Maximum Shear Stress in a Three Dimensional State of Stress

   https://doi.org/10.1007/s10659-022-09948-7  

   Warner, Derek H. ( December 2022 , Journal of Elasticity)
2. Lithology and Fault‐Related Stress Variations Along the TCDP Boreholes: The Stress State Before and After the 1999 Chi‐Chi Earthquake

   https://doi.org/10.1029/2021JB023290  

   Talukdar, Mayukh ; Sone, Hiroki ; Kuo, Li‐Wei ( February 2022 , Journal of Geophysical Research: Solid Earth)

   Understanding the stress state before and after an earthquake is essential to study how stress on faults evolves during the seismic cycle. This study integrates wellbore failure analysis, laboratory experiments, and edge dislocation model to study the stress state before and after the Chi‐Chi earthquake. The post‐earthquake in‐situ stress state observed along boreholes of the Taiwan Chelungpu‐fault Drilling Project (TCDP) is heterogeneous due to lithological variations. Along the borehole, we observe that drilling‐induced tensile fractures are only present in sandstones, whereas breakouts are mostly present in silt‐rich rocks. Laboratory experiments on TCDP cores also show that tensile and compressive strength are weaker in sandstones than in silt‐rich rocks. These observations imply that both maximum and minimum horizontal principal stresses are higher in silt‐rich intervals. Extended leak‐off tests in the TCDP borehole also show lower minimum horizontal stress in sand‐rich intervals, consistent with the above observations. We combine these observations to estimate a profile of stress magnitudes along the well which explains the variability of stress states found in previous studies. The stress heterogeneity we observed underlines the importance of acknowledging the spatial scale that the stress data represent. We then use an edge dislocation model constrained by GPS surface displacements obtained during Chi‐Chi earthquake to calculate the coseismic stress changes. Our inferred pre‐earthquake stress magnitudes, obtained by subtracting the coseismic stress change from the post‐earthquake stress, suggest subcritical stress state before the earthquake despite the large displacements observed during the Chi‐Chi earthquake in the region where TCDP encountered the fault.

    

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3. Combined effects of porosity and stress state on the failure behavior of laser powder bed fusion stainless steel 316L

   https://doi.org/10.1016/j.addma.2021.101862  

   Wilson-Heid, Alexander E. ; Beese, Allison M. ( March 2021 , Additive Manufacturing)

   null (Ed.)
4. Normal State O17 NMR Studies of Sr2RuO4 under Uniaxial Stress

   https://doi.org/10.1103/PhysRevX.9.021044  

   Luo, Yongkang ; Pustogow, A. ; Guzman, P. ; Dioguardi, A. P. ; Thomas, S. M. ; Ronning, F. ; Kikugawa, N. ; Sokolov, D. A. ; Jerzembeck, F. ; Mackenzie, A. P. ; et al ( May 2019 , Physical Review X)
5. State-dependent activity dynamics of hypothalamic stress effector neurons

   https://doi.org/10.7554/eLife.76832  

   Ichiyama, Aoi ; Mestern, Samuel ; Benigno, Gabriel B ; Scott, Kaela E ; Allman, Brian L ; Muller, Lyle ; Inoue, Wataru ( June 2022 , eLife)

   The stress response necessitates an immediate boost in vital physiological functions from their homeostatic operation to an elevated emergency response. However, the neural mechanisms underlying this state-dependent change remain largely unknown. Using a combination of in vivo and ex vivo electrophysiology with computational modeling, we report that corticotropin releasing hormone (CRH) neurons in the paraventricular nucleus of the hypothalamus (PVN), the effector neurons of hormonal stress response, rapidly transition between distinct activity states through recurrent inhibition. Specifically, in vivo optrode recording shows that under non-stress conditions, CRH PVN neurons often fire with rhythmic brief bursts (RB), which, somewhat counterintuitively, constrains firing rate due to long (~2 s) interburst intervals. Stressful stimuli rapidly switch RB to continuous single spiking (SS), permitting a large increase in firing rate. A spiking network model shows that recurrent inhibition can control this activity-state switch, and more broadly the gain of spiking responses to excitatory inputs. In biological CRH PVN neurons ex vivo, the injection of whole-cell currents derived from our computational model recreates the in vivo-like switch between RB and SS, providing direct evidence that physiologically relevant network inputs enable state-dependent computation in single neurons. Together, we present a novel mechanism for state-dependent activity dynamics in CRH PVN neurons. 

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