Damage Events Research Articles

Role of comorbidities in heart failure prognosis Part 2: Chronic kidney disease, elevated serum uric acid.

Despite improvements in pharmacotherapy, morbidity and mortality rates in community-based populations with chronic heart failure still remain high. The increase in medical complexity among patients with heart failure may be reflected by an increase in concomitant non-cardiovascular comorbidities, which are recognized as independent prognostic factors in this population. Heart failure and chronic kidney disease share many risk factors, and often coexist. The presence of kidney failure is associated with incremented risk of cardiovascular and non-cardiovascular mortality in heart failure patients. Chronic kidney disease is also linked with underutilization of evidence-based heart failure therapy that may reduce morbidity and mortality. More targeted therapies would be important to improve the prognosis of patients with these diseases. In recent years, serum uric acid as a determinant of cardiovascular risk has gained interest. Epidemiological, experimental and clinical data show that patients with hyperuricaemia are at increased risk of cardiac, renal and vascular damage and cardiovascular events. Moreover, elevated serum uric acid predicts worse outcome in both acute and chronic heart failure. While studies have raised the possibility of preventing heart failure through the use of uric acid lowering agents, the literature is still inconclusive on whether the reduction in uric acid will result in a measurable clinical benefit. Available evidences suggest that chronic kidney disease and elevated uric acid could worsen heart failure patients’ prognosis. The aim of this review is to analyse a possible utilization of these comorbidities in risk stratification and as a therapeutic target to get a prognostic improvement in heart failure patients.

Interacting effects of insect and ungulate herbivory on Scots pine growth

Most plants are subjected to damage from multiple species of herbivores, and the combined impact on plant growth can be non-additive. Since plant response to herbivores tends to be species specific, and change with repeated damage, the outcome likely depend on the sequence and number of attacks. There is a high likelihood of non-additive effects on plant growth by damage from mammals and insects, as mammalian herbivory can alter insect herbivore damage levels, yet few studies have explored this. We report the growth response of young Scots pine trees to sequential mammal and insect herbivory, varying the sequence and number of damage events, using an ungulate-pine-sawfly system. Combined sawfly and ungulate herbivory had both additive and non-additive effects on pine growth—the growth response depended on the combination of ungulate browsing and sawfly defoliation (significant interaction effect). Repeated sawfly herbivory reduced growth (compared to single defoliation) on un-browsed trees. However, on browsed trees, depending on when sawfly defoliation was combined with browsing, trees exposed to repeated sawfly herbivory had both higher, lower and the same growth as trees exposed to a single defoliation event. We conclude that the sequence of attacks by multiple herbivores determine plant growth response.

Exploring the effect of UV-C radiation on earthworm and understanding its genomic integrity in the context of H2AX expression

Maintaining genomic stability is inevitable for organism survival and it is challenged by mutagenic agents, which include ultraviolet (UV) radiation. Whenever DNA damage occurs, it is sensed by DNA-repairing proteins and thereby performing the DNA-repair mechanism. Specifically, in response to DNA damage, H2AX is a key protein involved in initiating the DNA-repair processes. In this present study, we investigate the effect of UV-C on earthworm, Perionyx excavatus and analyzed the DNA-damage response. Briefly, we expose the worms to different doses of UV-C and find that worms are highly sensitive to UV-C. As a primary response, earthworms produce coelomic fluid followed by autotomy. However, tissue inflammation followed by death is observed when we expose worm to increased doses of UV-C. In particular, UV-C promotes damages in skin layers and on the contrary, it mediates the chloragogen and epithelial outgrowth in intestinal tissues. Furthermore, UV-C promotes DNA damages followed by upregulation of H2AX on dose-dependent manner. Our finding confirms DNA damage caused by UV-C is directly proportional to the expression of H2AX. In short, we conclude that H2AX is present in the invertebrate earthworm, which plays an evolutionarily conserved role in DNA damage event as like that in higher animals.

Two Inferred Antique Earthquake Phases Recorded in the Roman Theater of Beit-Ras/Capitolias (Jordan)

AbstractA Roman theater is recently being excavated at Beit-Ras/Capitolias in Jordan, which is one of the Decapolis cities, founded before A.D. 97/98. This is an archaeoseismological study that aims to investigate the temporal and intensity impacts of past earthquakes on the theater’s existing structure. A rich set of earthquake archaeological effects were identified, including deformed arches, tilted and collapsed walls, chipped corners of masonry blocks, and extensional gaps, indicating a seismic intensity of VIII–IX. The study identified at least two significant destruction phases that took part in the damage of the theater, which may have contributed to the abandonment of its major use as a theater at different periods. This is based on field observations of construction stratigraphy and damage features, the assessment of the observed destruction, and literature reports. The date of the first phase is bracketed between the establishment of the city (before A.D. 97/98) and the date of an inscription found in the walled-up orchestra gate (A.D. 261). The most likely candidate earthquake(s) for this immense destruction are the A.D. 233 and/or 245 events. Other moderate and less damaging events may have also occurred within the region but are not mentioned in available catalogs. After a major restoration, another earthquake phase occurred between A.D. 261 and Late Roman–Early Byzantine times, when the scaena wall tilted and collapsed, rendering the building useless and beyond repair. Subsequently, the theater was then filled with debris and was abandoned. The most probable causative earthquake of the second phase of destruction is an event in A.D. 363. The article provides a rich discussion of potential causative earthquakes, based on archaeoseismological, construction stratigraphy observations, and calibrated intensity of historical earthquake-based attenuation modeling. It identifies the potential phases and types of destruction and reuse.

1,N6-Ethenoadenine: From Molecular to Biological Consequences

Genomic DNA is chemically reactive and therefore susceptible to damage by many exogenous and endogenous sources. Lesions produced from these damaging events can have various mutagenic and genotoxic consequences. This Perspective follows the journey of one particular lesion, 1,N6-ethenoadenine (εA), from its formation to replication and repair, and its role in cancerous tissues and inflammatory diseases. εA is generated by the reaction of adenine (A) with vinyl chloride or lipid peroxidation products. We present the miscoding properties of εA with an emphasis on how bacterial and mammalian cells can process lesions differently, leading to varied mutational spectra. But with information from these assays, we can better understand how the miscoding properties of εA lead to biological consequences and how genomic stability can be maintained via DNA repair mechanisms. We discuss how base excision repair (BER) and direct reversal repair (DRR) can minimize the biological consequences of εA lesions. Kinetic parameters of glycosylases and AlkB family enzymes are described, along with a discussion of the relative contributions of the BER and DRR pathways in the repair of εA. Because eukaryotic DNA is packaged in chromatin, we also discuss the impact of this packaging on BER and DRR, specifically in regards to repair of εA. Studying DNA lesions like εA in this context, from origin to biological implications, can provide crucial information to better understand prevention of mutagenesis and cancer.

In vivo analysis of the origin and characteristics of gaseous microemboli during catheter-mediated irreversible electroporation.

Aims Irreversible electroporation (IRE) ablation is a non-thermal ablation method based on the application of direct current between a multi-electrode catheter and skin electrode. The delivery of current through blood leads to electrolysis. Some studies suggest that gaseous (micro)emboli might be associated with myocardial damage and/or (a)symptomatic cerebral ischaemic events. The aim of this study was to compare the amount of gas generated during IRE ablation and during radiofrequency (RF) ablation.Methods and resultsIn six 60–75 kg pigs, an extracorporeal femoral shunt was outfitted with a bubble-counter to detect the size and total volume of gas bubbles. Anodal and cathodal 200 J IRE applications were delivered in the left atrium (LA) using a 14-electrode circular catheter. The 30 and 60 s 40 W RF point-by-point ablations were performed. Using transoesophageal echocardiography (TOE), gas formation was visualized. Average gas volumes were 0.6 ± 0.6 and 56.9 ± 19.1 μL (P < 0.01) for each anodal and cathodal IRE application, respectively. Also, qualitative TOE imaging showed significantly less LA bubble contrast with anodal than with cathodal applications. Radiofrequency ablations produced 1.7 ± 2.9 and 6.7 ± 7.4 μL of gas, for 30 and 60 s ablation time, respectively.Conclusion Anodal IRE applications result in significantly less gas formation than both cathodal IRE applications and RF applications. This finding is supported by TOE observations.

Archaeal DNA Repair Mechanisms.

Archaea often thrive in environmental extremes, enduring levels of heat, pressure, salinity, pH, and radiation that prove intolerable to most life. Many environmental extremes raise the propensity for DNA damaging events and thus, impact DNA stability, placing greater reliance on molecular mechanisms that recognize DNA damage and initiate accurate repair. Archaea can presumably prosper in harsh and DNA-damaging environments in part due to robust DNA repair pathways but surprisingly, no DNA repair pathways unique to Archaea have been described. Here, we review the most recent advances in our understanding of archaeal DNA repair. We summarize DNA damage types and their consequences, their recognition by host enzymes, and how the collective activities of many DNA repair pathways maintain archaeal genomic integrity.

Detecting damage initiation in short fiber composites via in-situ X-ray tomography and digital volume correlation

In-situ X-ray tomography is an effective means for the acquisition of time-resolved 3D images of fiber reinforced composites during mechanical loading and deformation. However, the manual comparison of corresponding in-situ X-ray images at successive loading instances to detect damage and its propagation is a time-consuming process. To improve the detection of damage using in-situ X-ray tomography, digital volume correlation (DVC), a full field 3D-strain technique that determines relative deformation between consecutive image volumes, was used. Specifically, regions of high strain were isolated from the heterogeneous strain computed from DVC within the microstructure and compared to manually detected damage. In this study, 59 out of 63 manually detected damage events, which included fiber breakage, micro-void nucleation, and fiber debonding, were within the search spaces of high strains beyond the 60th percentile threshold computed by DVC. Results of this study demonstrate the use of DVC as a tool to confine volumes of potential damage sites within the in-situ X-ray tomograms of composites to improve the efficiency of incipient damage detection.

Growing seismicity in the Sichuan Basin and its association with industrial activities.

In the Sichuan Basin, seismic activity has been low historically, but in the past few decades, a series of moderate to strong earthquakes have occurred. Especially since 2015, earthquake activity has seen an unprecedented continuous growth trend, and the magnitude of events is increasing. Following the M5.7 Xingwen earthquake on 18 Dec. 2018, which was suggested to be induced by shale gas hydraulic fracturing, a swarm of earthquakes with a maximum magnitude up to M6.0 struck Changning and the surrounding counties. Questions arose about the possible involvement of industrial actions in these destructive events. In fact, underground fluid injection in salt mine fields has been occurring in the Sichuan Basin for more than 70 years. Disposal of wastewater in natural gas fields has also continued for about 40 years. Since 2008, injection for shale gas development in the southern Sichuan Basin has increased rapidly. The possible link between the increasing seismicity and increasing injection activity is an important issue. Although surrounded by seismically active zones to the southwest and northwest, the Sichuan Basin is a rather stable region with a wide range of geological settings. First, we present a brief review of earthquakes of magnitude 5 or higher since 1600 to obtain the long-term event rate and explore the possible link between the rapidly increasing trend of seismic activity and industrial injection activities in recent decades. Second, based on a review of previous research results, combined with the latest data, we describe a comprehensive analysis of the characteristics and occurrence conditions of natural and injection-induced major seismic clusters in the Sichuan Basin since 1700. Finally, we list some conclusions and insights, which provide a better understanding of why damaging events occur so that they can either be avoided or mitigated, point out scientific questions that need urgent research, and propose a general framework based on geomechanics for assessment and management of earthquake-related risks.Electronic Supplementary MaterialSupplementary material is available for this article at 10.1007/s11430-020-9646-x and is accessible for authorized users.

Metamodel-Based Prediction of Structural Damages due to Tunneling-Induced Settlements

Tunneling-induced settlements in soft soil are inevitable and often suspected to impair buildings along the alignment. Public focus is thus targeted toward the consequences rather than the benefits of tunneling projects. To reduce the risk of damage, costly compensation is frequently applied in practice when crossing below critical structures, and critical scenarios are usually assessed via deterministic analyses of analytic models. These models are well known and overestimate potential damage since they conceive of buildings as idealized, simple Timoshenko beams without considering soil–structure interaction. The present study introduces an approach to providing an efficient prediction of realistically idealized structures prone to settlement-induced damages based on random input. This approach uses a nonlinear finite-element simulation of façades to render damage assessment. Global sensitivity analysis that uses both elementary effects and Sobol indices identifies random but irrelevant input that is consequently fixed to mean values. Response surfaces yield surrogate models for subsequent damage prediction via polynomial regression. As input, these surfaces employ ordinary distribution functions and extreme value distributions to ensure predictability at the tails. The inherent error of any prediction with response surfaces is first reduced by cross-validation and then comparatively rated with alternative forecasts through artificial neural networks. Finally, the mean probabilities of occurrence and standard deviations are determined considering the imperfection of the surrogate models for the classified damage events.

In-Situ Event Localization for Pipeline Monitoring System Based Wireless Sensor Network Using K-Nearest Neighbors and Support Vector Machine

Pipeline Monitoring Systems (PMS) benefits the most of recent developments in wireless remote monitoring since each pipeline would span for long distances which make conventional methods unsuitable. Precise monitoring and detection of damaging events requires moving large amounts of data between sensor nodes and base station for processing which require high bandwidth communication protocol. To overcome this problem, In-Situ processing can be practiced by processing the collected data locally at each node instead of the base station. However, this introduce a challenge to the limited resources available on the nodes. In this paper, a Wireless Sensor Network (WSN) was implemented for In-Situ Pipeline Monitoring System with proposed algorithms for event location estimation. The proposed algorithms include feature extraction (using ANOVA), dimensionality reduction using statistical procedure that is (Principle Component Analysis PCA) and data classification using supervised learning K-Nearest Neighbors (KNN) and Support Vector Machine (SVM). The proposed system was tested on pipelines in Al-Mussaib Gas Turbine Power Plant. During test, knocking events are applied at several distances relative to the nodes locations. Data collected at each node is filtered and processed locally in real time in each two adjacent nodes. The results of the estimation is then sent to the supervisor at base-station for display. The results show the proposed system ability to estimate the location of knocking event.

A Double Edged Sword Role of Interleukin-22 in Wound Healing and Tissue Regeneration.

Wound healing and tissue regeneration is an intricate biological process that involves repair of cellular damage and maintenance of tissue integrity. Cascades involved in wound healing and tissue regeneration highly overlap with cancer causing pathways. Usually, subsequent tissue damage events include release of a number of cytokines to accomplish post-trauma restoration. IL-22 is one of the cytokines that are immediately produced to initiate immune response against several tissue impairments. IL-22 is a fundamental mediator in inflammation, mucous production, protective role against pathogens, wound healing, and tissue regeneration. However, accumulating evidence suggests pivotal role of IL-22 in instigation of various cancers due to its pro-inflammatory and tissue repairing activity. In this review, we summarize how healing effects of IL-22, when executed in an uncontrollable fashion can lead to carcinogenesis.

How C-Reactive Protein Structural Isoforms With Distinctive Bioactivities Affect Disease Progression.

C-reactive protein (CRP) is a widely known, hepatically synthesized protein whose blood levels change rapidly and pronouncedly in response to any tissue damaging event associated with an inflammatory response. The synthesis and secretion of CRP is stimulated by interleukin-6, an early pleiotropic cytokine released by macrophages, endothelial, and other cells that are activated when localized normal tissue structures are compromised by trauma or disease. Serum CRP levels can change rapidly and robustly from 10-100-fold within 6–72 h of any tissue damaging event. Elevated blood levels correlate with the onset and extent of both activated inflammation and the acute phase biochemical response to the tissue insult. Because its functional bioactivity as the prototypic acute phase reactant has eluded clear definition for decades, diagnosticians of various conditions and diseases use CRP blood levels as a simple index for ongoing inflammation. In many pathologies, which involves many different tissues, stages of disease, treatments, and responses to treatments, its interpretive diagnostic value requires a deeper understanding of the localized tissue processes and events that contribute signals which regulate protective or pathological host defense bioactivities. This report presents concepts that describe how local tissue activation events can lead to a non-proteolytic, conformational rearrangement of CRP into a unique isoform with distinctive solubility, antigenicity, binding reactivities and bioactivities from that protein widely known and measured in serum. By describing factors that control the expression, tissue localization, half-life and pro-inflammatory amplification activity of this CRP isoform, a unifying explanation for the diagnostic significance of CRP measurement in disease is advanced.

Artesunate attenuates traumatic brain injury-induced impairments in rats.

BackgroundBlood–brain barrier (BBB) dysfunction and neuroinflammation induced by traumatic brain injuries (TBIs) cause a succession of secondary brain damage events and finally lead to a massive and progressive cerebral neuronal destruction. Artesunate, a semisynthetic artemisinin derivative, is a potential candidate for the management of cerebral damage induced by TBI due to its protective function to BBB and cerebral neurons.MethodsTo demonstrate the effect of artesunate to TBI-induced BBB dysfunction and neural damage, TBI rat model was constructed by cortical impact injury. Behavioral experiments were used to estimate the impact of the combined treatment on rats. Western blotting was performed to demonstrate the protein levels in the brain tissues of rats. Quantitative real-time PCRs were utilized to investigate the alteration in the expression of various RNA levels. The chemokine levels were estimated by ELISA.ResultsArtesunate treatment attenuated the impact caused by TBI on rat brain and improved the long-term neurological recover. Artesunate treatment protected the integrity of BBB and inhibited neuroinflammation. Artesunate treatment promoted the phosphorylation of Akt and inhibited the phosphorylation of glycogen synthase kinase (GSK)-3β in TBI rat model.ConclusionArtesunate protected rats from TBI-induced impairments of BBB and improved longer-term neurological outcomes.

Hazardous Situations and Accidents Caused by Light and Medium Unmanned Free Balloon Flights

The article deals with the presentation and analysis of hazardous situations, damage events and accidents caused by light and medium unmanned free balloons and the parts of them. During the flights of these balloons, emergencies, hazardous situations, and accidents can occur in many different ways. Hazardous situations and damages at the process of landing and after it have also many different variations. At the end of the article we draw conclusions based on the previous analyzes.

On the influence of overlap topology on the tensile strength of composite bonded joints: Single overlap versus overlap stacking

The goal of this study is to explore new topologies for adhesively bonded composite overlap joints in order to improve their strength under tensile loading. Multiple stacked overlaps, also referred as finger joints, are compared with single overlap topologies. The quasi-static tensile behaviour of single lap joints with two overlap lengths 12.7 mm and 25.4 mm are compared to finger joints with 1 and 2 stacked overlaps through thickness with constant 12.7 mm overlap length. Two composite adherend stacking sequences are tested for each topology [0/90]4s and [90/0]4s.A non-linear FE-analysis is performed to analyse the shear and peel stresses along the adhesive bond line. A difference in peak shear and peel stress, at the tip of the bonded region could be observed: (i) for 1 finger, the peak peel stress is higher than in the single lap joint configurations because the beneficial effect of avoiding eccentricity in the finger joint is outperformed by the detrimental effect of reducing to half the adherend stiffness at the overlap; (ii) for 2 fingers, the stress field changes significantly leads to a 23% decrease in peak shear and 33% in peak peel stress, compared to the single lap joint topologies.In addition, experimental lap shear tests are performed and monitored using acoustic emission technique, to follow the damage events. Different trends at damage initation and at maximum load are believed to result from how the damage propagates inside the joint. A topology with 2 fingers and layup [90/0]4s, which fails entirely inside the adherend, provides the lowest peak shear and peel stress and the highest load at damage initiation. It is however outperformed in maximum load by a single lap joint topology with layup [0/90]4s, with mostly cohesive failure. It is further found that, unlike in single overlap topologies, the most dominant stress component for damage initiation inside the finger joints is the in-plane tensile stress, at the butt joint resin pockets, rather than peel stresses at the overlap region. Lastly, if weight efficiency is the main requirement, a finger joint design can effectively replace a single overlap joint design. However, for absolute maximum joint strength, the single overlap joint is a better choice than the finger joint.

Adjustability of exposed elements by updating their capacity for resistance after a damaging event: application to an earthquake\u2013tsunami cascade scenario

The 2011 Great East Japan earthquake and tsunami remind us once again that these types of cascade event can occur and cause considerable damage. The scientific community realizes the need for rapid theoretical and practical progress on cascade events to provide field teams with the necessary tools and information for action during these types of events. The earthquake damage scenario for Martinique and Guadeloupe islands (French West Indies) has already been performed within the framework of French governmental projects, but these areas, in the vicinity of the French West Indies subduction zone, are also subject to tsunami events. In this study, we propose to perform a combined scenario in which an earthquake is followed by a tsunami, as it could arrive one day, considering the seismic characteristics and potential of such a subduction zone. The vulnerability of the buildings is defined considering local specific information based on several years of field inventories and inspections and is later classified into one of the 36 model building types of HAZUS. The calculation of the damages due to tsunamis follows the HAZUS methodologies. The main novelty of our study is the calculation of damage due to the two phenomena occurring one after the other, not in parallel, as is calculated in the existing literature. Therefore, for the calculation of the damages due to the second event (i.e. the tsunami), the vulnerability characteristics of the initial structure are reduced, considering the damage state of the construction after the first event (i.e. the earthquake). Hence, in our case, this calculation approach allows us to update the number of exposed elements and their changed vulnerabilities considering the damages due to the earthquake, since certain structures are already damaged by the earthquake before the arrival of the tsunami wave. The results coming from our study and our manner of treating the cascading hazards are putting into perspective with the Hazus method for combining damages coming from earthquake and the damages coming from consequently tsunami. The results expressed as the sum of the damages in both most damaged states, Extensive and Complete, are more or less in the same range of values for both studies (our study and HAZUS 2017). However, a trend of having more percentage of complete damages (and hence, less the Extensive damages) with our method than the ones obtained with the Hazus combination can be important information for crisis managing. This is a first result for the French West Indies territory, but anyway, more studies should be carried out in order to check this trend and eventually to confirm and validate this issue for others territories with others bathymetries, vulnerabilities and seismological features.

Seismic vulnerability analysis of buried polyethylene pipeline based on finite element method

Lifeline engineering plays an important role in the development of human society and economy. A large number of seismic damage events show that the buried polyethylene pipeline is easy to be damaged under the earthquake action, however, the research on the seismic vulnerability of the buried polyethylene pipeline is still lacking. In this paper, the seismic vulnerability of buried polyethylene pipeline is studied based on the finite element method (FEM). The FE model and vulnerability analysis model are established. The establishment of the FE model mainly considers different site categories, soils damping that calculated by the Rayleigh damping theory and the wave pattern and input mode of seismic wave. At the same time, the grid sensitivity analysis and model verification are carried out. The vulnerability model includes the seismic demand model and the seismic capacity model. Based on the previous research, the damage state of the polyethylene pipeline is defined, and the sample combination of pipeline and seismic wave is considered to calculate the vulnerability curve of the pipeline. In all, this study provides a useful idea for the rapid evaluation of the seismic performance of buried polyethylene pipes.

Corrosion-induced changes on Hertzian contact damage in cemented carbides

In this study, the influence of corrosion on the mechanical response and damage induced under Hertzian indentation is assessed for three cemented carbides with metallic binders of different chemical nature. Corrosion degradation is introduced in a controlled way, before subsequent spherical indentation testing, by immersing specimens in a stirred acidic medium. Results reveal quite strong corrosion effects on indentation stress-strain response and contact damage scenario. Such detrimental influence is found to be dependent on both the ratio between indentation depth and thickness of the corroded layer as well as chemical nature of the binder. In this regard, critical loads for emergence and evolution of specific damage events (i.e. ring and radial cracks, and even specimen failure) are proposed as figures of merit for material selection under the combined action of corrosion and contact loads. Within this context, the hardmetal grade with Co-base binder and addition of Cr is found to be the best option, among the three cemented carbides studied in this investigation. It points out the consideration of the synergic interaction between corrosion resistance and hardness/toughness correlation for microstructural design optimization of hardmetals under service-like conditions. These statements are supported by the relevant corrosion-induced changes also observed, by means of advanced characterization techniques, in terms of deformation/failure micromechanisms at both surface and subsurface levels.

An Investigation of the Factors Controlling the Mechanical Behaviour of Slender Naturally Fractured Pillars

Previous studies on the strength and deformability of pillars in hard-rock mines have demonstrated that the influence of natural fractures diminishes with increasing pillar width. Jointing conditions and fracture intensity/intersections play a critical role in the behaviour of slender pillars (width-to-height ratio less than 0.5). An important challenge is the characterization of rock mass damage as a function of the natural fracture network and loading conditions. In this paper, we present advanced pre-processing methodologies to measure fracture intensity and fracture density prior to loading and relate those measures to the evolution of damage (intensity and density) with increasing pillar load. A hybrid finite-discrete element method (FDEM) with fracture mechanics capabilities is used to simulate the mechanical behaviour of synthetic pillar models with different embedded discrete fracture traces of similar total length. Newly developed post-processing methodologies are used to capture the location of damage events, track rock mass damage intensity and density as the simulation progresses and relate those changes to the modelled pillar strength. We believe the results of this study provide useful insights on rock mass damage evolution.