Coseismic Coulomb stress changes induced by a 2020-2021 M_(W)>7.0 Alaska earthquake sequence in and around the Shumagin gap and its influence on the Alaska-Aleutian subduction interface

Three M_(W)>7.0 earthquakes in 2020-2021 occurred in the Shumagin seismic gap and its adjacent area of the Alaska-Aleutian subduction zone,including the Mw7.8 Simeonof thrust earthquake on July 22,2020,the M_(W)7.6 Sand Point strike-slip earthquake on October 19,2020,and the M_(W)8.2 Chignik thrust earthquake on July 29,2021.The spatial and temporal proximity of these three earthquakes prompts us to probe stress-triggering effects among them.Here we examine the coseismic Coulomb stress change imparted by the three earthquakes and their influence on the subduction interface.Our results show that:(1)The Simeonof earthquake has strong loading effects on the subsequent Sand Point and Chignik earthquakes,with the Coulomb stress changes of 3.95 bars and 2.89 bars,respectively.The Coulomb stress change caused by the Sand Point earthquake at the hypocenter of the Chignik earthquake is merely around 0.01 bars,suggesting the negligible triggering effect on the latter earthquake;(2)The triggering effects of the Simeonof,Sand Point,and Chignik earthquakes on aftershocks within three months are not well pronounced because of the triggering rates of 38%,14%,and 43%respectively.Other factors may have played an important role in promoting the occurrence of these aftershocks,such as the roughness of the subduction interface,the complicated velocity structure of the lithosphere,and the heterogeneous prestress therein;(3)The three earthquakes caused remarkable coseismic Coulomb stress changes at the subduction interface nearby these mainshocks,with an average Coulomb stress change of 3.2 bars in the shallow region directly inwards the trench.

Exosomes derived from microglia overexpressing miR-124-3p alleviate neuronal endoplasmic reticulum stress damage after repetitive mild traumatic brain injury

We previously reported that miR-124-3p is markedly upregulated in microglia-derived exosomes following repetitive mild traumatic brain injury.However,its impact on neuronal endoplasmic reticulum stress following repetitive mild traumatic brain injury remains unclear.In this study,we first used an HT22 scratch injury model to mimic traumatic brain injury,then co-cultured the HT22 cells with BV2 microglia expressing high levels of miR-124-3p.We found that exosomes containing high levels of miR-124-3p attenuated apoptosis and endoplasmic reticulum stress.Furthermore,luciferase reporter assay analysis confirmed that miR-124-3p bound specifically to the endoplasmic reticulum stress-related protein IRE1α,while an IRE1αfunctional salvage experiment confirmed that miR-124-3p targeted IRE1αand reduced its expression,thereby inhibiting endoplasmic reticulum stress in injured neurons.Finally,we delivered microglia-derived exosomes containing miR-124-3p intranasally to a mouse model of repetitive mild traumatic brain injury and found that endoplasmic reticulum stress and apoptosis levels in hippocampal neurons were significantly reduced.These findings suggest that,after repetitive mild traumatic brain injury,miR-124-3 can be transferred from microglia-derived exosomes to injured neurons,where it exerts a neuroprotective effect by inhibiting endoplasmic reticulum stress.Therefore,microglia-derived exosomes containing miR-124-3p may represent a novel therapeutic strategy for repetitive mild traumatic brain injury.

Exercise-induced modulation of miR-149-5p and MMP9 in LPS-triggered diabetic myoblast ER stress: licorice glycoside E as a potential therapeutic target

Background:This study explores the relationship between endoplasmic reticulum(ER)stress and diabetes,particularly focusing on the impact of physical exercise on ER stress mechanisms and identifying potential therapeutic drugs and targets for diabetes-related sepsis.The research also incorporates traditional physical therapy perspectives,emphasizing the genomic insights gained from exercise therapy in disease management and prevention.Methods:Gene analysis was conducted on the GSE168796 and GSE94717 datasets to identify ER stress-related genes.Gene interactions and immune cell correlations were mapped using GeneCard and STRING databases.A screening of 2,456 compounds from the TCMSP database was performed to identify potential therapeutic agents,with a focus on their docking potential.Techniques such as luciferase reporter gene assay and RNA interference were used to examine the interactions between microRNA-149-5p and MMP9.Results:The study identified 2,006 differentially expressed genes and 616 miRNAs.Key genes like MMP9,TNF-α,and IL1B were linked to an immunosuppressive state.Licorice glycoside E demonstrated high affinity for MMP9,suggesting its potential effectiveness in treating diabetes.The constructed miRNA network highlighted the regulatory roles of MMP9,IL1B,IFNG,and TNF-α.Experimental evidence confirmed the binding of microRNA-149-5p to MMP9,impacting apoptosis in diabetic cells.Conclusion:The findings highlight the regulatory role of microRNA-149-5p in managing MMP9,a crucial gene in diabetes pathophysiology.Licorice glycoside E emerges as a promising treatment option for diabetes,especially targeting MMP9 affected by ER stress.The study also underscores the significance of physical exercise in modulating ER stress pathways in diabetes management,bridging traditional physical therapy and modern scientific understanding.Our study has limitations.It focuses on the microRNA-149-5p-MMP9 network in sepsis,using cell-based methods without animal or clinical trials.Despite strong in vitro findings,in vivo studies are needed to confirm licorice glycoside E’s therapeutic potential and understand the microRNA-149-5p-MMP9 dynamics in real conditions.

The soybean GmPUB21-interacting protein GmDi19-5 responds to drought and salinity stresses via an ABA-dependent pathway

Drought-induced protein 19(Di19) is a Cys2/His2 zinc-finger protein that functions in plant growth and development and in tolerance to abiotic stresses.Gm PUB21,an E3 ubiquitin ligase,negatively regulates drought and salinity response in soybean.We identified potential interaction target proteins of Gm PUB21by yeast two-hybrid c DNA library screening,Gm Di19-5 as a candidate.Bimolecular fluorescence complementation and glutathionine-S-transferase pull-down assays confirmed the interaction between Gm Di19-5 and Gm PUB21.Gm Di19-5 was induced by Na Cl,drought,and abscisic acid(ABA) treatments.Gm Di19-5 was expressed in the cytoplasm and nucleus.Gm Di19-5 overexpression conferred hypersensitivity to drought and high salinity,whereas Gm Di19-5 silencing increased drought and salinity tolerance.Transcripts of ABA-and stress response-associated genes including Gm RAB18 and Gm DREB2A were downregulated in Gm Di19-5-overexpressing plants under drought and salinity stresses.ABA decreased the protein level of Gm Di19-5 in vivo,whereas Gm PUB21 increased the decrease of Gm Di19-5 after exogenous ABA application.The accumulation of Gm PUB21 was also inhibited by Gm Di19-5.We conclude that Gm PUB21 and Gm Di19-5 collaborate to regulate drought and salinity tolerance via an ABA-dependent pathway.

Temperature and stress fields in electron beam welded Ti-15-3 alloy to 304 stainless steel joint with copper interlayer sheet

Electron beam welding of Ti-15-3 alloy to 304 stainless steel （STS） using a copper filler metal was carried out. The temperature fields and stress distributions in the Ti/Fe and Ti/Cu/Fe joint during the welding process were numerically simulated and experimentally measured. The results show that the rotated parabola body heat source is fit for the simulation of the electron beam welding. The temperature distribution is asymmetric along the weld center and the temperature in the titanium alloy plate is higher than that in the 304 STS plate. The thermal stress also appears to be in asymmetric distribution. The residual tensile stress mainly exists in the weld at the 304 STS side. The copper filler metal decreases the peak temperature and temperature grade in the joint as well as the residual stress. The longitudinal and lateral residual tensile strengths reduce by 66 MPa and 31 MPa, respectively. From the temperature and residual stress, it is concluded that copper is a good filler metal candidate for the electron beam welding of Ti-15-3 titanium alloy to 304 stainless steel.

Chlorogenic acid alleviates hypoxic-ischemic brain injury in neonatal mice

Recent studies have shown that chlorogenic acid(CGA),which is present in coffee,has protective effects on the nervous system.However,its role in neonatal hypoxic-ischemic brain injury remains unclear.In this study,we established a newborn mouse model of hypoxic-ischemic brain injury using a modified Rice-Vannucci method and performed intraperitoneal injection of CGA.We found that CGA intervention effectively reduced the volume of cerebral infarct,alleviated cerebral edema,restored brain tissue structure after injury,and promoted axon growth in injured brain tissue.Moreover,CGA pretreatment alleviated oxygen-glucose deprivation damage of primary neurons and promoted neuron survival.In addition,changes in ferroptosis-related proteins caused by hypoxic-ischemic brain injury were partially reversed by CGA.Furthermore,CGA intervention upregulated the expression of the key ferroptosis factor glutathione peroxidase 4 and its upstream glutamate/cystine antiporter related factors SLC7A11 and SLC3A2.In summary,our findings reveal that CGA alleviates hypoxic-ischemic brain injury in neonatal mice by reducing ferroptosis,providing new ideas for the treatment of neonatal hypoxic-ischemic brain injury.

microRNA-627-5p inhibits colorectal cancer cell proliferation,migration and invasion by targeting Wnt2

BACKGROUND microRNA-627-5p(miR-627-5p)dysregulation has been observed in several cancer types,such as hepatocellular carcinoma,oral squamous cell carcinoma,glioblastoma multiforme,and gastric cancer.The biological function of miR-627-5p in colorectal cancer(CRC)growth and metastasis is yet unclear.AIM To investigate the effects of miR-627-5p on the malignant biological properties of colorectal malignant tumour cells by targeting Wnt2.METHODS The levels of miR-627-5p in colorectal tumour tissues were assessed in Gene Expression Omnibus datasets.In order to identify Wnt2 transcript expression in CRC tissues,quantitative real-time polymerase chain reaction(qRT-PCR)analysis was used.Luciferase reporter tests were used to explore whether miR-627-5p might potentially target Wnt2.Wnt2 transcript and protein levels were detected in CRC cells with high miR-627-5p expression.To learn more about how miR-627-5p affects CRC development,migration,apoptosis,and invasion,functional experiments were conducted.Cotransfection with the overexpression vector of Wnt2 and miR-627-5p mimics was utilized to verify whether overexpression of Wnt2 could cancel the impact of miR-627-5p in CRC.Western blot and qRT-PCR were conducted to investigate the effects of miR-627-5p on the Wnt/β-catenin signalling pathway.RESULTS miR-627-5p was notably decreased in colorectal tumour tissues,while the gene level of Wnt2 was notably upregulated.A dual luciferase reporter assay revealed that miR-627-5p specifically targets the 3’-untranslated regions of Wnt2 and miR-627-5p upregulation markedly reduced the protein and gene expression of Wnt2 in CRC cells.In vitro gain-of-function assays displayed that miR-627-5p overexpression decreased CRC cells’capabilities to invade,move,and remain viable while increasing apoptosis.Wnt2 overexpression could reverse the suppressive functions of miR-627-5p.Moreover,upregulation of miR-627-5p suppressed the transcript and protein levels of the downstream target factors in the canonical Wnt/β-catenin signalling,such as c-myc,CD44,β-catenin,and cyclinD1.CONCLUSION miR-627-5p acts as a critical inhibitory factor in CRC,possibly by directly targeting Wnt2 and negatively modulating the Wnt/β-catenin signalling,revealing that miR-627-5p could be a possible treatment target for CRC.

Effects of bottom shear stresses on the wave-induced dynamic response in a porous seabed:PORO-WSSI (shear) model

When ocean waves propagate over the sea floor,dynamic wave pressures and bottom shear stresses exert on the surface of seabed.The bottom shear stresses provide a horizontal loading in the wave-seabed interaction system,while dynamic wave pressures provide a vertical loading in the system.However,the bottom shear stresses have been ignored in most previous studies in the past.In this study,the effects of the bottom shear stresses on the dynamic response in a seabed of finite thickness under wave loading will be examined,based on Biot＇s dynamic poro-elastic theory.In the model,an ＂u-p＂ approximation will be adopted instead of quasi-static model that have been used in most previous studies.Numerical results indicate that the bottom shear stresses has certain influences on the wave-induced seabed dynamic response.Furthermore,wave and soil characteristics have considerable influences on the relative difference of seabed response between the previous model（without shear stresses） and the present model（with shear stresses）.As shown in the parametric study,the relative differences between two models could up to 10% of p0,depending on the amplitude of bottom shear stresses.

Interfacial stress transfer behavior in a specially-shaped fiber/matrix pullout test

Specially designed fibers are widely used in engineering practice because the specially-designed shape can help to improve the bonding strength of the fiber and the interface. Studied in this paper is the interfacial shear stress transfer behavior on both sides of the specially designed fiber when it is being pulled out; in which automatic analysis of three-dimensional photoelasticity is employed and the finite element method is adopted. The results show that the stress transfer occurs mainly in the region near the fiber＇s embedded end where the stress reaches its critical point, leading to debonding of the interface. Before debonding, as the pullout loading increases, the peak value of shear stress transfers along the fiber from the embedded end to the interior of the matrix, and then stops at the hooked part of the fiber because of its impediment. When the interface begins to debond as the load increases, the shear stress can be transferred to the hooked part.

A fractional differential constitutive model for dynamic stress intensity factors of an anti-plane crack in viscoelastic materials

Fractional differential constitutive relationships are introduced to depict the history of dynamic stress inten- sity factors （DSIFs） for a semi-infinite crack in infinite viscoelastic material subjected to anti-plane shear impact load. The basic equations which govern the anti-plane deformation behavior are converted to a fractional wave-like equation. By utilizing Laplace and Fourier integral transforms, the fractional wave-like equation is cast into an ordinary differential equation （ODE）. The unknown function in the solution of ODE is obtained by applying Fourier transform directly to the boundary conditions of fractional wave-like equation in Laplace domain instead of solving dual integral equations. Analytical solutions of DSIFs in Laplace domain are derived by Wiener-Hopf technique and the numerical solutions of DSIFs in time domain are obtained by Talbot algorithm. The effects of four parameters α, β, b1, b2 of the fractional dif- ferential constitutive model on DSIFs are discussed. The numerical results show that the present fractional differential constitutive model can well describe the behavior of DSIFs of anti-plane fracture in viscoelastic materials, and the model is also compatible with solutions of DSIFs of anti-plane fracture in elastic materials.

Prediction of flow stress of Ti-15-3 alloy with artificial neural network

Hot compression experiments were conducted on Ti 15 3 alloy specimens using Gleeble 1500 Thermal Simulator.These tests were focused to obtain the flow stress data under various conditions of strain,strain rate and temperature. On the basis of these data, the predicting model for the nonlinear relation between flow stress and deformation strain,strain rate and temperature for Ti 15 3 alloy was developed with a back propagation artificial neural network method. Results show that the neural network can reproduce the flow stress in the sampled data and predict the nonsampled data well. Thus the neural network method has been verified to be used to tackle hot deformation problems of Ti 15 3 alloy. [

Thermoelastic stress analysis of multilayered films in a micro-thermoelectric cooling device

This paper presents an analytical solution for the thermoelastic stress in a typical in-plane＇s thin-film micro- thermoelectric cooling device under different operating con- ditions. The distributions of the permissible temperature fields in multilayered thin-films are analytically obtained, and the characteristics, including maximum temperature dif- ference and maximum refrigerating output of the thermo- electric device, are discussed for two operating conditions. Analytical expressions of the thermoelastic stresses in the layered thermoelectric thin-films induced by the tempera- ture difference are formulated based on the theory of mul- tilayer system. The results demonstrate that, the geometric dimension is a significant factor which remarkably affects the thermoelastic stresses. The stress distributions in layers of semiconductor thermoelements, insulating and support- ing membrane show distinctly different features. The present work may profitably guide the optimization design of high- efficiency micro-thermoelectric cooling devices.

Lateral resonances in initial stressed 1-3 piezocomposites

A theoretical analysis of the lateral resonances in 1-3 piezocomposites with poling initial stress is conducted using the Bloch wave theory. Based on the linear piezoelectricity theory, theoretical formulations that include initial stress for the propagation of acoustic plane waves are made. Numerical calculations are performed to study the effects of the initial stress on the lateral mode frequencies and the stop band. It is found that lateral mode frequencies increase with the piezoelectricity of the piezocomposites, but decrease with the poling initial stress. The influence of the initial shear stress on the lateral mode frequencies is minimal, and can thus be neglected.

Effect of varying normal stress on stability and dynamic motion of a spring-slider system with rate- and state-dependent friction

Incorporating rate and state friction laws, stability of linearly stable （i.e., with stiffness greater than the critical value） spring-slider systems subjected to triggering perturbations was analyzed under variable normal stress condition, and comparison was made between our results and that of fixed normal stress cases revealed in previous studies. For systems associated with the slip law, the critical mag- nitude of rate steps for triggering unstable slips are found to have a similar pattern to the fixed normal stress case, and the critical velocity steps scale with a/（b - a） when k = kcr for both cases. The rate-step boundaries for the variable normal stress cases are revealed to be lower than the fixed normal stress case by 7 %-16 % for a relatively large ct = 0.56 with （b - a）/a ranging from 0.25 to 1, indicating easier triggering under the variable normal stress condition with rate steps. The difference between fixed and variable normal stress cases decreases when the α value is smaller. In the same slip- law-type systems, critical displacements to trigger instability are revealed to be little affected by the variable normal stress condition. When k 〉 kcr（V,）, a spring-slider system with the slowness law is much more stable than with the slip law,suggesting that the slowness law fits experimental data better when a single state variable is adopted. In stick-slip motions, the variable normal stress case has larger stress drops than the constant normal stress case. The variable normal stress has little effect on the range of slip velocity in systems associated with the slowness law, whereas systems associated with the slip law have a slowest slip velocity immensely smaller than the fixed normal stress case, by ~ 10 orders of magnitude.

Unveiling the planar deformation mechanisms for improved formability in pre-twinned AZ31 Mg alloy sheet at warm temperature

To investigate the role of pre-twins in Mg alloy sheets during warm planar deformation,the stretch forming is conducted at 200℃.Results suggest the formability of the pre-twinned AZ31 Mg alloy sheet is enhanced to 11.30 mm.The mechanisms for the improved formability and the deformation behaviors during the planar stretch forming are systematically investigated based on the planar stress states.The Schmid factor for deformation mechanisms are calculated,the results reveal that planar stress states extremely affect the Schmid factor for{10-12}twinning.The detwinning is activated and the prismatic slip is enhanced in the pre-twinned sheet,especially under the planar extension stress state in the outer region.Consequently,the thickness-direction strain is accommodated better.The dynamic recrystallization(DRX)type is continuous DRX(CDRX)regardless of the planar stress state.However,the CDRX degree is greater under the planar extension stress state.Some twin lattices deviate from the perfect{10-12}twinning relation due to the planar compression stress state and the CDRX.The basal texture is weakened when the planar stress state tends to change the texture components.

Multi-scale analysis of subgrid stress and energy dissipation in turbulent channel flow

In present study, the subgrid scale （SGS） stress and dissipation for multiscale formulation of large eddy simulation are analyzed using the data of turbulent channel flow at Ret = 180 obtained by direct numerical simulation. It is found that the small scale SGS stress is much smaller than the large scale SGS stress for all the stress components. The dominant contributor to large scale SGS stress is the cross stress between small scale and subgrid scale motions, while the cross stress between large scale and subgrid scale motions make major contributions to small scale SGS stress. The energy transfer from resolved large scales to subgrid scales is mainly caused by SGS Reynolds stress, while that between resolved small scales and subgrid scales are mainly due to the cross stress. The multiscale formulation of SGS models are evaluated a priori, and it is found that the small- small model is superior to other variants in terms of SGS dissipation.

Comparison of Low Stress Mechanical Properties of Light Weight Wool and Wool Blend Fabrics using the KES-F and FAST Instruments

This study compares the test results of the FAST (Fabric Assurance by Simple Testing) with those of the KES - F (Kawabata Evaluation Systems for Fabrics) for a range of nineteen light weight wool and wool blend fabrics in terms of the low - stress mechanical properties of bending, shear, and tensile deformation. It is found that there are very significant correlations between the corresponding parameters for extensibility and shear rigidity obtained from the test results of the two systems. The correlation between the values of bending rigidity obtained from the two systems is only moderate. Furthermore, for the fabrics tested in this study, the values of bending rigidity, shear rigidity, and extensibility measured using the KES - F instruments are higher than those of the corresponding parameters measured using the FAST instruments. The linear regression equation is given for each pair of corresponding parameter.

MODELING THE STRESS-STRAIN CURVES UNDER DYNAMIC RECRYSTALLIZATION

An analytical model for dynamic recrystallization (DRX) is studied based on the relative grain size model proposed by Sakai and Jonas, and the characteristic flow behaviors under DRX are analyzed and simulated. Introducing the variation of dynamic grain size and the heterogeneous distribution of disolo- cation densities densities under DRX,a simple method for modeling and simulating DRX processes is developed by using Laplace transformation theory. The results derived from the present model agree well with the experimental results in literatures. This simulation can reproduce a number of features in DRX flow behaviors, for example,single and multiple peak flow behaviors followed by a steady state flow, the transition between them, and so on.

NUMERICAL SIMULATION OF STRESS-STRAIN DISTRIBUTIONS FOR WELD METAL SOLIDIFICATION CRACKING IN STAINLESS STEEL

This paper analyzed the characteristics of welding solidification crack of stainless steels,and clearly re- vealed the the of the deformation in the molten - the pool and the solidification shrinkage on the stress - strain fields in the trail of molten - weld pool.Moreover, rheologic properties of the alloys in solid - liquid zone were also obtained by measuring the hading and unloading deform curves of the steels.As a result, a numerical model for simulation of stress - strain distributions of welding solidifi- cation crack was developed. On the basis of the model,the thesis simulated the driving force of solidifi- cation crack of stainless steels, that is, stress - strain fields in the trail of molten-weld pool with fi- nite element method.

Z α-1 antitrypsin deficiency and the endoplasmic reticulum stress response

The serine proteinase inhibitor α-1 antitrypsin(AAT) is produced principally by the liver at the rate of 2 g/d.It is secreted into the circulation and provides an antiprotease protective screen throughout the body but most importantly in the lung,where it can neutralise the activity of the serine protease neutrophil elastase.Mutations leading to def iciency in AAT are associated with liver and lung disease.The most notable is the Z AAT mutation,which encodes a misfolded variant of the AAT protein in which the glutamic acid at position 342 is replaced by a lysine.More than 95% of all individuals with AAT def iciency carry at least one Z allele.ZAAT protein is not secreted effectively and accumulates intracellularly in the endoplasmic reticulum(ER) of hepatocytes and other AAT-producing cells.This results in a loss of function associated with decreased circulating and intrapulmonary levels of AAT.However,the misfolded protein acquires a toxic gain of function that impacts on the ER.A major function of the ER is to ensure correct protein folding.ZAAT interferes with this function and promotes ER stress responses and inflammation.Here the signalling pathways activated during ER stress in response to accumulation of ZAAT are described and therapeutic strategies that can potentially relieve ER stress are discussed.