Research on the mechanism of rockburst induced by mined coal-rock linkage of sharply inclined coal seams

In recent years,the mining depth of steeply inclined coal seams in the Urumqi mining area has gradually increased.Local deformation of mining coal-rock results in frequent rockbursts.This has become a critical issue that affects the safe mining of deep,steeply inclined coal seams.In this work,we adopt a perspective centered on localized deformation in coal-rock mining and systematically combine theoretical analyses and extensive data mining of voluminous microseismic data.We describe a mechanical model for the urgently inclined mining of both the sandwiched rock pillar and the roof,explaining the mechanical response behavior of key disaster-prone zones within the deep working face,affected by the dynamics of deep mining.By exploring the spatial correlation inherent in extensive microseismic data,we delineate the“time-space”response relationship that governs the dynamic failure of coal-rock during the progression of the sharply inclined working face.The results disclose that(1)the distinctive coal-rock occurrence structure characterized by a“sandwiched rock pillar-B6 roof”constitutes the origin of rockburst in the southern mining area of the Wudong Coal Mine,with both elements presenting different degrees of deformation localization with increasing mining depth.(2)As mining depth increases,the bending deformation and energy accumulation within the rock pillar and roof show nonlinear acceleration.The localized deformation of deep,steeply inclined coal-rock engenders the spatial superposition of squeezing and prying effects in both the strike and dip directions,increasing the energy distribution disparity and stress asymmetry of the“sandwiched rock pillar-B3+6 coal seam-B6 roof”configuration.This makes worse the propensity for frequent dynamic disasters in the working face.(3)The developed high-energy distortion zone“inner-outer”control technology effectively reduces high stress concentration and energy distortion in the surrounding rock.After implementation,the average apparent resistivity in the rock pillar and B6 roof substantially increased by 430%and 300%,respectively,thus guaranteeing the safe and efficient development of steeply inclined coal seams.

Adenosine triphosphate induced cell death: Mechanisms and implications in cancer biology and therapy

Adenosine triphosphate(ATP)induced cell death(AICD)is a critical cellular process that has garnered substantial scientific interest for its profound relevance to cancer biology and to therapeutic interventions.This comprehensive review unveils the intricate web of AICD mechanisms and their intricate connections with cancer biology.This review offers a comprehensive framework for comprehending the multifaceted role of AICD in the context of cancer.This is achieved by elucidating the dynamic interplay between systemic and cellular ATP homeostasis,deciphering the intricate mechanisms governing AICD,elucidating its intricate involvement in cancer signaling pathways,and scrutinizing validated key genes.Moreover,the exploration of AICD as a potential avenue for cancer treatment underscores its essential role in shaping the future landscape of cancer therapeutics.

Streptozotocin induced Alzheimer's disease like changes and the underlying neural degeneration and regeneration mechanism

Alzheimer’s disease（AD）is a neurodegenerative disorder which is remarkably characterized by pathological hallmarks that include neurofibrillary tangles,neuronal loss extracellular senile plaques containing aggregated amyloid beta（Aβ）,and neurofibrillary tangles composed of the hyperphosphorylated form of the microtubule protein tau.It is the most common form of dementia which is characterized by severe neurodegenerative changes such as loss of neurons and synapses in brain（Kamat et al.,2014）.

Physical-mechanical properties of microbially induced calcite precipitation-treated loess and treatment mechanism

Loess disintegration can lead to geotechnical engineering problems,e.g.,slope erosion,wetting-induced landslide,and hydroconsolidation.Microbially induced calcite precipitation(MICP)technique is a potential loess reinforcing method.This study investigated the physical-mechanical properties of MICP-treated loess and then explored the mechanism of loess modification by MICP.Here,loess first underwent MICP treatment,i.e.,mixing loess with Sporosarcina pasteurii and cementation solution(CS).Then,the effects of the CS concentration(0.2,0.6,0.8,and 1 M)on the physical and mechanical properties of the MICP-treated loess were tested.Finally,the static contact angle test,scanning electron microscopy(SEM),and X-ray diffractometry(XRD)were conducted to study the mechanism of MICP treatment on loess.Results showed the following property changes of loess after MICP treatment:the liquid limit decreased by 1.7%,the average particle size increased from 6 to 47μm,the specific gravity decreased from 2.65 to 2.43,the unconfined compressive strength increased from 37 to 71 k Pa,and the disintegration time increased from 10 to 25 min.Besides,the shear strength also increased,and the shear strength parameters(cohesion c and internal friction angle?)varied with the CS concentration.The static contact angle tests indicated that the water absorption ability of loess was reduced after MICP treatment.SEM and XRD results verified that the CaCO_(3)from MICP was attributed to the above results.The above findings explained the mechanism of MICP treatment of loess:the CaCO_(3)coats and cements the particles,and fills the pores of loess,improving the strength and water stability of loess.

Formation mechanism and modulation of electromagnetically induced transparency-like transmission in side-coupled structures

Based on Fabry model and finite-different time-domain(FDTD) method, the plasmonic structure composed of a metal-insulator-metal(MIM) bus waveguide and a side-coupled resonator was investigated. It is found that the transmission features can be regulated by the cavity width and coupling distance. Electromagnetically induced transparency(EIT)-like transmission can be excited by adding an identical resonator on the pre-existing structure. Combining the foregoing theoretical analysis with coupled mode theory(CMT), the formation process of the EIT-like transmission was detailedly analyzed. EIT-like transmission can also be excited in plasmonic structure with two detuned resonators. By altering the structure parameters, the transparency window can be purposefully modulated. With the merits of compact structure and simplicity in fabrication, the proposed structures may have a broad prospect of applications in highly integrated optical circuits.

The Mechanism of Acute Lung Injury Induced by Nickel Carbonyl in Rats

Nickel carbonyl is a highly toxic metal compound produced from the reaction that occurs between nickel and carbon monoxide under pressure. As previously reported, nickel carbonyl can cause acute aspiration pneumonia, and animal experiments showed it was toxic to animal lung, liver, brain, and other vital organs[1]. However, few studies have investigated nickel carbonyl poisoning in humans.

HUMAN-INDUCED LANDSLIDES IN CHINA:MECHANISM STUDY AND ITS IMPLICATIONS ON SLOPE MANAGEMENT

Human activity duo to rapid increasing of the economy in China has become so wide and intense since 1980s that it comes to the most active factor affecting the earth surface geomorphology process and provoke the most important impact to environment in recent two decades. Some typical human-induced landslides are introduced. Their generalfeatures,including distribution,types,time series of occurrence and mechanism are summarized. A classification system of landslides is suggested based on their geological backgrounds and formation mechanism. Finally,some aspects of slope management and human activity control are discussed to different types of landslides.

Differential Proteomics Reveals the Potential Injury Mechanism Induced by Heavy Ion Radiation in Mice Ovaries

In the present study, we used a proteomics approach based on a two-dimensional electrophoresis （2-DE） reference map to investigate protein expression in the ovarian tissues of pubertal Swiss-Webster mice subjected to carbon ion radiation （CIR）. Among the identified proteins, ubiquitin carboxy-terminal hydrolase L1 （UCH-L1） is associated with the cell cycle[1] and that it influences proliferation in ovarian tissues. We analyzed the expression of UCH-L1 and the proliferation marker proliferation cell nuclear antigen （PCNA） following CIR using immunoblotting and immunofluorescence. The proteomics and biochemical results provide insight into the underlying mechanisms of CIR toxicity in ovarian tissues.

Coupling mechanism between mining-induced deformation and permeability of coal

The coupling mechanism between mining-induced mechanical behavior and gas permeability of coal is effectively obtained in laboratory.This study means significant understanding of the prevention of coal-gas outburst.The testing samples of coal were drilled from the 14120 mining face at the depth of690 m.Based on the redistribution of stress during the excavation,the coupling test between mechanical state and seepage has been designed using the triaxial servo-controlled seepage equipment for thermofluid-solid coupling of coal containing methane.It is the result that there are two main factors influencing the mining-induced mechanical behavior of coal,such as the change ofσ_1-σ_3 andΔσ_1-Δσ_3.The failure mode mainly depends on the value ofσ_1-σ_3,and the peak strength value mainly depends on the value ofΔσ_1-Δσ_3.The difference of mechanical response between geostress and mining-induced stress has been obtained,which can be a theoretical support for safe mining such as reasonable gas drainage,prevention of coal-gas outburst and gas over-limit.

Neuroprotection induced by NMDA preconditioning as a strategy to understand brain tolerance mechanism

Excitotoxicity refers to toxicity caused by abnormal concentrations of glutamate in the synaptic cleft that may lead to neuronal death. Since its description, the phenomenon of glutamatergic excitotoxicity has been implicated in the physiopathology of a wide range of neurological and psychiatric disorders, from acute brain damage such as traumatic brain injury, ischemia as well as chronic condi- tions like epilepsy, depression and neurodegenerative pathologies such as Huntington＇s, Parkinson＇s and Alzheimer＇s diseases. Exces- sive stimulation of glutamatergic receptors, mainly N-methyl-D-as- partate （NMDA） receptors （NMDAR）, can have numerous adverse effects on the cell viability, including increased nitric oxide release （NO）, activation of proteases, increased production of reactive oxygen （ROS） and nitrogen （RNS） species and massive influx of calcium ions （Ca2＋）, resulting in cell death. Thus, the use of strategies that modulate the excitotoxic cell damage represents a perspective for the treatment of diseases such as Parkinson＇s and Alzheimer＇s diseases, ischemia, traumatic brain injury （TBI） and seizures.

Melastatin-related transient receptor potential 2 channel in Aβ_(42)-induced neuroinflammation: implications to Alzheimer's disease mechanism and development of therapeutics

Alzheimer’s disease （AD） is an age-related eurodegenerative disease that represents the most common cause of dementia among the elderly people. With the increasingly aging population, AD has presented an overwhelming healthcare challenge to modern society; the World Alzheimer Report 2015 has estimated that 46.8 million people worldwide lived with dementia in 2015 and this number will rise to 74.7 million in 2030 and that the total cost of dementia was 818 billion in US$ in 2015 and will reach two trillion in 2030. Post-mortem studies have identified two histopathological hallmarks in the brains of AD patients; extracellular senile plaque with elevated deposition of amyloid β （Aβ） peptides, and intracellular neurofibrillary tangle composed of hyper-phosphorylated microtubule-associated protein tau.Etiologically, progressive neuronal loss within the cerebral cortex and hippocampus regions of the brain leads to irreversible decline in, and eventually complete loss of, memory and other cognitive functions that afflict AD patients. The widely-accepted amyloid cascade hypothesis for AD pathogenesis holds that accumulation and aggregation of neurotoxic Aβ peptides, due to imbalance of their generation and clearance as a result of changes in genetic makeup, aging and/or exposure to environmental risk factors, is a major and early trigger of AD. This hypothesis has continuously gained support by preclinical and clinical studies （Selkoe and Hardy, 2016）. However, the intensive and costly drug discovery efforts over the past decades based on such a hypothesis have proved extremely frustrating in developing effective therapeutics to treat or slow down the progress of AD, highlighting the need for more research to improve our understanding towards the cellular and molecular mechanisms by which Aβ peptides bring about neurotoxicity and cognitive dysfunction.

Autonomic mechanism for chronic atrial electrical remodeling induced by rapid atrial pacing in ambulatory danines

Objetives The mechanism for changes in the electrophysiological properties of the atria during rapid pacing induced atrial fibrillation(AF) is not well understood.We aimed to investigate the contribution of intrinsic cardiac autonomic nervous system(ICANS) in chronic atrial electrical remodeling and AF induced by rapid atrial pacing for 4 weeks. Methods Twelve adult mongrel dogs weighing 15 to 20 kg were assigned to two groups;group 1(experimental group,n= 7) and group 2(control group,n =5).All dogs were anesthetized with propofol and mechanically ventilated via endotracheal tubes.The chest was entered via bilateral mini-thoracotomy at the fourth intercostals space.Bipolar pacing electrode was sutured to the right atrial appendage.Four-electrode catheters(Biosense-Webster,Diamond Bar,CA) were secured to allow recording at the right and left atriaum.All tracings from the electrode catheters were amplified and digitally recorded using a computer-based Bard Laboratory System (CR Bard Inc,Billerica,MA).Electrograms were filtered at 50 to 500 Hz.Continuous rapid pacing(600 bpm, 2×threshold[TH]) was performed at the right atrial appendage. Ganglionated Plexi(GP) was localized by applying high frequency stimulation(HFS;20 Hz,0.1ms duration, 0.5 to 4.5 V)with a bipolar stimulation-ablation probe electrode (AtriCure,West Chester,OH).Group1 underwent ablation of bilateral GP and ligament of Marshall followed by 4-week pacing.Group 2 underwent sham operaton without ablation of GP and ligament of Marshall followed by 4-week pacing.The effective refractory period(ERP) and window of vulnerability(WOV) were measured at 2×TH before(baseline) and every week after GP ablation.WOV was defined as the difference between the longest and the shortest coupling interval of the premature stimulus that induced AF.GP consist of the anterior right ganglionated plexi(ARGP) located in the fat pad at the right superior pulmonary vein(RSPV)-atrial junction;the inferior right ganglionated plexi(IRGP) located at the inferior vena cava/right atrial junction;the superior left ganglionated plexi(SLGP) at the left superior pulmonary vein(LSPV) /left atrial junction and the inferior left ganglionated plexi(ILGP) at the left inferior pulmonary vein (LIPV)/left atrial junction.Results Immediately after ablation, the ERP in Group 1 became markedly longer and started to shorten gradually during the first 2 weeks,then stabilized at the 4th week.Compared to Group2,the ERP of Group1 was significantly longer in the first 3 weeks(P【 0.05),but no obvious difference at the 4th week in either the right or left atrium(P】0.05).In Group 1,AF could not be induced(WOV=0)in the first 3 weeks after ablation, and at the 4th week,AF was induced in 2 of 7 dogs.In Group2,WOV progressively widened during the 4-week period. AF could not be induced in 5 of 7 dogs in Group 1 and 1 of 5 dogs in Group 2 during the 4-week pacing period. Conclusions The intrinsic cardiac autonomic nervous system (ICANS) plays an important role in the early stage of atrial electrical remodeling induced by rapid atrial pacing.On the other hand,with time passing by,its effect on the formation of AF decreases gradually,which suggests that ICANS may account for a non-dominant factor in the late stage of the rapid pacing-induced chronic atrial fibrillation.

Effect and mechanism of adrenomedullin on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury

Objective To investigate the effect and mechanism of adrenomedullin ( AM ) on apoptosis of renal tubular epithelial cell in rats induced by renal ischemia reperfusion injury. Methods Thirty-two Wistar rats were randomly divided into 4 groups: control group,IRI group, empty plasmid group and AM group. One week after re-

Hydrogen effect on the mechanical behaviour and microstructural features of a Fe-Mn-C twinning induced plasticity steel

The influences of hydrogen on the mechanical properties and the fracture behaviour of Fe-22Mn-0.6C twinning induced plasticity steel have been investigated by slow strain rate tests and fractographic analysis.The steel showed high susceptibility to hydrogen embrittlement,which led to 62.9%and 74.2%reduction in engineering strain with 3.1 and 14.4 ppm diffusive hydrogen,respectively.The fracture surfaces revealed a transition from ductile to brittle dominated fracture modes with the rising hydrogen contents.The underlying deformation and fracture mechanisms were further exploited by examining the hydrogen effects on the dislocation substructure,stacking fault probability,and twinning behaviour in pre-strained slow strain rate test specimens and notched tensile specimens using coupled electron channelling contrast imaging and electron backscatter diffraction techniques.The results reveal that the addition of hydrogen promotes planar dislocation structures,earlier nucleation of stacking faults,and deformation twinning within those grains which have tensile axis orientations close to<111>//rolling direction and<112>//rolling direction.The developed twin lamellae result in strain localization and micro-voids at grain boundaries and eventually lead to grain boundary decohesion.

Driving pressure in mechanical ventilation:A review

Driving pressure(ΔP)is a core therapeutic component of mechanical ventilation(MV).Varying levels ofΔP have been employed during MV depending on the type of underlying pathology and severity of injury.However,ΔP levels have also been shown to closely impact hard endpoints such as mortality.Considering this,conducting an in-depth review ofΔP as a unique,outcome-impacting therapeutic modality is extremely important.There is a need to understand the subtleties involved in making sureΔP levels are optimized to enhance outcomes and minimize harm.We performed this narrative review to further explore the various uses ofΔP,the different parameters that can affect its use,and how outcomes vary in different patient populations at different pressure levels.To better utilizeΔP in MV-requiring patients,additional large-scale clinical studies are needed.

Phase-dependent double optomechanically induced transparency in a hybrid optomechanical cavity system with coherently mechanical driving

We propose a scheme that can generate tunable double optomechanically induced transparency in a hybrid optomechanical cavity system.In this system, the mechanical resonator of the optomechanical cavity is coupled with an additional mechanical resonator and the additional mechanical resonator can be driven by a weak external coherently mechanical driving field.We show that both the intensity and the phase of the external mechanical driving field can control the propagation of the probe field, including changing the transmission spectrum from double windows to a single-window.Our study also provides an effective way to generate intensity-controllable, narrow-bandwidth transmission spectra, with the probe field modulated from excessive opacity to remarkable amplification.

Numerical simulation of tumor-induced angiogenesis influenced by the extra-cellular matrix mechanical environment

To investigate tumor-induced angiogenesis under the influence of the mechanical environments inside and outside the tumor, mathematical model of tumor angiogenesis was developed. In the model, extra-cellular matrix （ECM） was treated as a thin plane. The displacement of ECM is obtained from the force balance equation consisted of the ECs traction, the ECM visco-elastic forces and the exter- nal forces. Simulation results show that a layered capillary network is obtained with a well vascularized region at the periphery of the tumor. The present model can be used as a valid theoretical method in the basic researches in tumorinduced angiogenesis.

The Role of Non-Coding RNA in Vascular Remodeling Induced by Mechanical Stress

Vascular remodeling is the essential pathogenic process of various cardiovascular disorders,including hypertension,atherosclerosis,stroke,and restenosis after vein graft.The main characterization of vascular remodeling is abnormal variations of vascular cell phenotype,morphological structure and functions such as migration,hypertrophy,proliferation and apoptosis.Numerous researches revealed that mechanical stress,including shear stress and cyclic stretch,participates in physiological vascular homeostasis,or pathophysiological vascular remodeling.The understanding of mechanobiological mechanism in vascular remodeling will play a unique role in understanding human physiology and disease,and will generate important theoretical and clinical significance [2].Non-coding RNAs are newly recognized RNAs which cannot be translated into proteins but are involved in epigenetic modification of gene regulation.The studies revealed that non-coding RNAs,such as microRNAs(miRNAs)and long noncoding RNAs(long ncRNAs,IncRNA),as well as small interfering RNAs(siRNAs),piwi-interacting RNAs(piRNAs),small nucleolar RNAs(snoRNAs),play essential roles in the regulation of various processes,such as metabolism,development,cell proliferation,cell apoptosis,cell differentiation,oncogenesis and vascular homeostasis[5].However,the roles of non-coding RNAs in the cardiovascular system under mechanical stresses are still not clarified.Our recent researches detected the mechanical regulation of IncRNAs and miRNAs in vascular remodeling.LncRNAs are non-protein-coding transcripts that are longer than 200 nucleotides(nt),which is an arbitrary cut-off value that distinguishes these transcripts from other small RNAs.Unlike the well-established mechanism of microRNA action,the functional mode of IncRNAs is not fully understood.Increasing evidence shows that IncRNAs modulate gene expression via a multilevel-regulated pathway.Given their large number and complicated functional modes,lncRNAs are emerging as important regulators of a variety of cellular responses,developmental processes and diseases.Using a gene microarray,we screened the differences in the IncRNAs and mRNAs between spontaneously hypertensive rats(SHR)and Wistar Kyoto rats(WKY).The results showed that 68 IncRNAs and 255 mRNAs were up-regulated in the aorta of SHR,while 167 IncRNAs and 272 mRNAs were down-regulated.Expressions of the screened IncRNAs,including XR007793,were validated by real-time PCR.A co-expression network was composed,and gene function was analysed using Ingenuity Pathway Analysis.In vitro,vascular smooth muscle cells(VSMCs)were subjected to cyclic stretch at a magnitude of 5%(physiological normotensive cyclic stretch)or 15%(pathological hypertensive cyclic stretch)by Flexercell-5000TM.15%-cyclic-stretch increased XR007793 expression.XR007793 knockdown attenuated VSMC proliferation and migration and inhibited co-expressed genes such as signal transducers and activators of transcription 2(stat2),LIM domain only 2(lmo2)and interferon regulatory factor 7(irf7)[4].Illuminating the role of IncRNAs in vascular remodeling induced by hyper mechanical stretch may provide deeper insight into the mechanobiological mechanism underlying hypertension,and contribute to identifying potential targets for hypertension therapy.miRNAs are endogenous,non-coding,single-stranded RNAs of 18-22 nucleotides that constitute a novel class of gene regulators.miRNAs bind to their target genes within their 3’-untranslated regions(3’-UTRs),leading to direct degradation of mRNA or translational repression by a complete,i.e.in plants,or incomplete,i.e.in animals,complement respectively.Our resent works revealed several important mechano-responsive miRNA and their potential effects in vascular remodeling.Forexample,miRNA-33 is regulated by cyclic stretch in the grafted vessels,which targets to BMP3 and subsequent modulates smad signaling pathway.The miRNA-33-BMP3-smad pathway protects against venous VSMC proliferation in response to arterial cyclic stretch.Therefore,miRNA-33 may be a potential therapeutic target in autologous vein grafted surgery,and locally overexpression of miR-33 may attenuates neointimal hyperplasia of grafted human saphenous vein [3].The unpublished data revealed that 15%cyclic stretch also significantly elevated the expression of miRNA-124-3p which bound to the 3’UTR of Lmna mRNA,and then negatively regulated protein expression of lamin A/C which is the important skeletal proteins in nucleus.In addition to primary intracellular locations of miRNAs,our recent study showed that miRNAs can be secreted and protected extracellularly via inclusion into membrane-derived vesicles including microparticles.Microparticles are extracellular vesicles ranging from 0.1 to 1μm in size and have been shown to deliver various bioactive molecules,i.e.,chemokines,enzymes and miRNAs,to recipient cells.Increasing evidence shows that microparticles play a pivotal role in many pathological processes,such as cancer,inflammatory diseases and cardiovascular disease.Our present study showed that platelet-derived microparticles(PMPs),which are released by active platelets,are important vehicles for communication and play crucial roles in inducing abnormal EC proliferation in hypertension.In briefly,EC proliferation was increased in renal hypertensive rats established by abdominal aortic coarctation compared to control rats and that elevated thrombin in plasma promoted platelet activation,which may induce the release of PMPs.miRNA array and qPCR revealed a higher level of miRNA-142-3p in platelets and PMPs.In vitro,PMPs delivered miRNA-142-3p into ECs and enhanced EC proliferation via Bcl-2-associated transcription factor 1(BCLAF1)and its downstream genes.These results indicated that PMPs deliver miRNA-142-3p from activated platelets into ECs and that miRNA-142-3p may play important roles in EC dysfunction under hypertensive conditions and might be a novel therapeutic target for maintaining EC homeostasis in hypertension[1].These results provide possible mechanisms by which non-coding RNAs regulate cellular functions under different mechanical stresses,and suggest a novel potential therapeutic approach for vascular remodeling.The further studies on noncoding RNAs may provide new insight into understanding the mechanism of vascular remodeling in different various cardiovascular disorders,and may provide novel targets for the maintenance of vascular homeostasis.