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A complete inventory of 16 mineral type localities and 1 rock type locality in Romania, as well as their assessed geoheritage characteristics and values are presented for the first time. Thirty-nine mineral species, one chemical element and one common rock type were discovered, described and named in Romania. Most of these are closely linked to traditional mining areas: the Baia Mare region, the Apuseni Mts. and the Banat region. Three mineral type localities are outstandingly rich: Săcărâmb/Nagyág in the southern Apuseni Mts. (8 new minerals), Baia Sprie/Felsőbánya in the Baia Mare region (6 new minerals), and Băița Bihor/Rézbánya in the Northern Apuseni Mts. (6 new minerals). The scientific, educational and touristic value and significance of the type localities regarded as „geosites” and „geodiversity sites” are discussed. Based on the quantitative assessment of the scientific, educational and touristic values, the type localities were hierarchically classified, Baia Sprie, Săcărâmb and Măgura Uroiului being the highest ranked. From the geoconservation perspective, site protection and valuation strategies at local and/or regional scales are envisaged. [ABSTRACT FROM AUTHOR]

This study proposes a fractal damage calculation method that understands the blasting damage laws at the macroscopic, mesoscopic, and microscopic scales of rock. The findings indicated that the binary graph derived from the Moments algorithm can represent minute cracks and exhibit less noise within the image. This makes the algorithm suitable for identifying and extracting macroscopic damage. A three-dimensional (3D) reconstruction technique offers visualization of the macroscopic rock damage following an explosion. The extent of this damage is quantitatively assessed using the box dimension. In addition, a multifractal method is introduced to comprehensively evaluate the macroscopic and mesoscopic damage to rock post-blasting. The multifractal dimension calculations analysis reveals that the mesoscopic damage to rock following blasting is a significant factor in the overall blasting damage. The box dimension presents a straightforward, macroscopic evaluation method for assessing 3D macroscopic fractures. On the other hand, the multifractal dimension can more accurately evaluate the macroscopic cracks and mesoscopic damage resulting from blasting. Both methods emphasize different aspects and are equally effective for assessing blasting damage. Highlights: This study proposes a fractal damage calculation method that understands the blasting damage laws at the macroscopic, mesoscopic, and microscopic scales of rock. The box dimension is a straightforward macroscopic evaluation method for assessing 3D macroscopic fractures. The multifractal dimension more accurately evaluates the macroscopic cracks and mesoscopic damage from blasting. After ordinary charge initiations, blasting damage exhibited a bimodal distribution along the borehole's axis, peaking in the charging section. [ABSTRACT FROM AUTHOR]

Creep tests under constant stress are among the most important tests for investigating the time-dependent behavior of rock. In previous studies, creep tests were conducted under various loading and environmental conditions; however, it was very difficult to demonstrate accelerating creep at failure at stresses less than 50% of strength in conventional creep tests. In this study, a new test method is proposed that combines an alternating loading-rate test and a creep test in the post-failure region. The accelerating creep as well as the loading-rate dependence of strength were successfully obtained simultaneously from a single specimen. This test method was applied to three rock types under dry and wet conditions. The results of Sanjome andesite under both dry and wet conditions, Kimachi sandstone under dry conditions, and Tage tuff under dry conditions showed a similar relationship between creep strain, creep strain rate, and residual time (i.e., creep lifetime minus elapsed time), from high to low creep stress levels, and a close relationship between accelerating creep and the loading-rate dependence of strength. Further, the mechanism responsible for the time dependence was found not to change significantly from high to low stress levels. In contrast, different results were obtained when high and low creep stress levels were compared in Kimachi sandstone and Tage tuff under wet conditions. The larger increase in creep strain with increasing creep strain rate at lower creep stress levels was related to the shape of the stress–strain curve in the post-failure region. Highlights: A new test method was proposed that combined an alternating loading-rate test and a creep test in the post-failure region. Accelerating creep at failure was discussed in detail based on the test results from high to low creep stress levels. Test results showed a close relationship between accelerating creep and the loading-rate dependence of strength. [ABSTRACT FROM AUTHOR]

Background: Rho-kinase (ROCK) regulates actomyosin contraction, coronary vasospasm, and cytoskeleton dynamics. ROCK and of NADPH oxidase (NOX) play an essential role in cardiovascular disease and proteoglycan synthesis, which promotes atherosclerosis by trapping low density lipoprotein. ROCK is activated by endothelin-1 (ET1) and transactivates the transforming growth factor beta receptor (TGFβR1), intensifying Smad signaling and proteoglycan production. This study aimed to identify the role of myosin light chain phosphatase (MLCP) as a downstream target of ROCK in TβR1 transactivation. Methods: Vascular smooth muscle cells were treated with ET1 and inhibitors of ROCK and MLCP were added. The phosphorylation levels of Smad2C, myosin light chain (MLC), and MLCP were monitored by western blot, and the mRNA expression of chondroitin 4-O-sulfotransferase 1 (C4ST1) was assessed by quantitative real-time PCR. Results: We examined ROCK's role in ET1-induced TGFβR1 activation. ROCK phosphorylated MLCP at the MYPT1 T853 residue, blocked by the ROCK inhibitor Y27632. ROCK also increased MLC phosphorylation and actomyosin contraction in response to ET1, enhanced by the phosphatase inhibitor Calyculin A. Calyculin A also increased C4ST1 expression, GAG-chain synthesizing enzymes. Conclusions: This work suggests that ROCK is involved in ET1-mediated TβR1 activation through increased MLCP phosphorylation, which leads to Smad2C phosphorylation and stimulates C4ST1 expression. [ABSTRACT FROM AUTHOR]

Small GTPases are monomeric (approximately 21 kDa) proteins that regulate a number of biological processes, such as vesicle transport, cell division cycle, cell migration, invasion, adhesion, proliferation, and DNA repair. They are also involved in carcinogenesis and neurodegenerative diseases. Some of these proteins, such as the Rho family proteins, are essential regulators of actin cytoskeleton, controlling cell adhesion and motility. This review examines both normal and pathological processes in human cells that are regulated by small GTPases of the Rho family. Particular attention is paid to small GTPase inhibitors and their use in the treatment of various diseases. [ABSTRACT FROM AUTHOR]

Rock specimens of the reservoir's core material from the Chayanda oil and gas condensate field (OGCF) were tested using the Triaxial Independent Load Test System of the Ishlinsky Institute for Problems in Mechanics, Russian Academy of Sciences (TILTS) in order to experimentally study the effect exerted by desalinization of reservoir rocks on their strain, strength, and filtration characteristics. According to the study data, desalinization considerably increases a rock permeability. Strain and strength properties of the studied rocks change toward softening (except for an internal friction angle), nevertheless remaining relatively high. Based on the experimental physical modeling of the pressure reducing process at the bottom of a horizontal well using TILTS, a slight decrease in elastic and strength properties of the Chayanda OGCF reservoir rocks after their desalinization should not affect the stability of the well's walls. The results obtained make it possible to draw the important practical conclusion: when operating the field at the stage of salt washing out due to water filtration under the operation process, a dramatic increase in the risks related to reservoir destruction and higher sand production should not be expected. [ABSTRACT FROM AUTHOR]

Septic cardiomyopathy (SCM) is one of the most serious complications of sepsis. The present study investigated the role and mechanism of upstream stimulatory factor 2 (USF2) in SCM. Serum samples were extracted from SCM patients and healthy individuals. A murine model of sepsis was induced by caecal ligation and puncture (CLP) surgery. Myocardial injury was examined by echocardiography and HE staining. ELISA assay evaluated myocardial markers (CK-MB, cTnI) and inflammatory cytokines (TNF-α, IL-1β, IL-18). Primary mouse cardiomyocytes were treated with lipopolysaccharide (LPS) to simulate sepsis in vitro. RT-qPCR and Western blot were used for analyzing gene and protein levels. CCK-8 assay assessed cell viability. NLRP3 was detected by immunofluorescence. ChIP, RIP and dual luciferase reporter assays were conducted to validate the molecular associations. USF2 was increased in serum from SCM patients, septic mice and primary cardiomyocytes. USF2 silencing improved the survival of septic mice and attenuated sepsis-induced myocardial pyroptosis and inflammation in vitro and in vivo. Mechanistically, USF2 could directly bind to the promoter of miR-206 to transcriptionally inhibit its expression. Moreover, RhoB was confirmed as a target of miR-206 and could promote ROCK activation and NLRP3 inflammasome formation. Moreover, overexpression of RhoB remarkably reversed the protection against LPS-induced inflammation and pyroptosis mediated by USF2 deletion or miR-206 overexpression in cardiomyocytes. The above findings elucidated that USF2 knockdown exerted a cardioprotective effect on sepsis by decreasing pyroptosis and inflammation via miR-206/RhoB/ROCK pathway, suggesting that USF2 may be a novel drug target in SCM. [ABSTRACT FROM AUTHOR]

Rock naturally contains numerous defects, and both loading rate and defect geometry affect the loading capacity of rock structures when subjected to dynamic impact loads. Understanding the rate-dependent mechanical response and characterizing geometry-related fracture parameter of defected rocks are crucial to safety assessment of rock engineering. In this paper, the effects of loading rate and notch parameter on dynamic brittle fracture behavior of Fangshan granite weakened by a blunt V-notch are experimentally studied. First, the dynamic fracture experiments on blunt V-notched semi-circular bend (BVNSCB) specimen of Fangshan granite with different notch geometries are performed using the split Hopkinson pressure bar (SHPB) system. Second, the dynamic fracture processes of blunt V-notched rocks are recorded using an ultrahigh-speed camera, and the mechanical responses to different impact loading conditions are obtained via digital image correlation (DIC) method. Third, the effects of loading rate and notch parameter on the dynamic fracture parameters including notch fracture toughness, crack propagation toughness, and crack velocity are discussed to reveal the fracture mechanism of blunt V-notched rocks subjected to impact loads. It is found that dynamic notch fracture toughness obtained from DIC method is usually larger than that measured directly from conventional maximum impact load method. The maximum tangential stress (MTS) criterion eliminating the effect of the fracture process zone (FPZ) at blunt V-notch tip is used to correct the apparent notch fracture toughness value measured from the maximum load method. The results show that corrected notch fracture toughness values are in good agreements with those obtained from the DIC method. This study is significant for dynamic fracture analyses and strength assessments of rock masses containing notches or other defects with complex geometry. Highlights: Effects of loading rate and notch geometry on dynamic fracture behavior of blunt V-notched rocks are studied. Dynamic notch fracture toughness and crack propagation toughness are simultaneously determined. DIC method is used to track the development of FPZ at blunt V-notch tip and quantify the FPZ length. [ABSTRACT FROM AUTHOR]

It is of great significance to study the flexural properties and behaviour of rock in rock mechanics and engineering applications, such as tunneling, mining and underground space development. However, there are few studies related to the flexural properties of rock considering different elastic parameters in tension and in compression. This study focuses on rock flexural strength subjected to bending loading. A series of four-point bending tests (FPBTs) on prismatic beams of granite were carried out. The flexural strength of rock was theoretically determined under different assumptions based on the elastic and elastic‒plastic theory considering different elastic properties of rock in tension and in compression. Then, a comparison was made between the indirect tensile strength measured by the Brazilian test and the flexural strength acquired from the FPBT. The effects of specimen shape and heterogeneity on the flexural behaviour of rock were analysed by FEM-based numerical simulation. The results show that the calculated flexural strengths considering the elastoplastic and bimodulus properties of rock are lower than those without considering the properties and are closer to the Brazilian tensile strength of rock. The flexural strengths of rock increase with increasing ratios of height to thickness. Heterogeneity plays a crucial role in the flexural properties of rock. The more homogeneous the rock is, the higher its flexural strength. The findings in this paper facilitate a better understanding of the flexural properties of rock. [ABSTRACT FROM AUTHOR]

In many geological conditions, obtaining the static elastic moduli of crustal rocks is an essential subject for accurate mechanical analyses of crust. The elastic wave method may be the best choice if rock specimens cannot be taken since elastic wave propagation can be applied to in-situ environments. Although many signs of progress have been made in the elastic wave method, some issues still restrict the accurate extraction of static moduli and its applications. A review of this method and its further research prospect is urgently needed. With this purpose, this paper summarized and analyzed the published experimental data about the relationship between the static and dynamic Young's moduli of rock, and the frequency dependence of wave velocities and dynamic elastic moduli. P- and S-wave velocities, Young's, and bulk moduli of rock, especially the saturated rock, have strong frequency dependence in a wide frequency range of 10–6–106 Hz. Different rocks or conditions (such as water content, amplitude, and pressure), have different frequency-dependent characteristics. The current elastic wave method can be classified into two methods: the empirical correlation method and the multifrequency ultrasonic method. The basic principle, advantages, and disadvantages of both methods are analyzed. Especially, the reasonability of the multifrequency ultrasonic method was elaborated given the nonlinear elasticity, strain level/rate, and pores/cracks in rock materials. Existing problems and prospects on the two methods are also pointed out, such as the choice of a proper empirical correlation, accurate determination of the critical P- and S-wave velocities, the prediction of Young's modulus at each strain level, and the reasonability of the method under various water contents and fracture structures. [ABSTRACT FROM AUTHOR]

This study presents the fabrication of polylactic acid microwell patterns using a lithography-based replica molding method for the development of three-dimensional (3D) neural cell-based assays. SH-SY5Y human neuroblastoma cells interfaced with these patterns, and cell growth and morphological characteristics were evaluated with and without an inhibitor of the rho-associated coiled-coil kinase (ROCK) signaling pathway. The results revealed that the culture systems of SH-SY5Y cells on the microwell patterns could be categorized as two-dimensional (2D), 3D, and near-two-dimensional (N2D), according to their location within a dynamic multidimensional culture system. Furthermore, the geometric features of the patterns significantly impact the efficiency of the conversion model, which was characterized by the proliferation and percentage of cells in different culture systems. The rearrangement of the microfilament cytoskeleton and morphological spreading of cells on the patterns were suppressed by the downregulation of the ROCK signaling pathway. The inhibition of the ROCK signaling pathway had a time-dependent effect on the proliferation and migration of cells on the patterned substrate, where topographical cues, cell morphology, and density played pivotal roles. Consequently, the proposed system serves as a practical model for studying the functional behaviors of neural cells by dynamically assembling multidimensional culture systems on the same platform, facilitating the development of cell-based assays. ROCK-myosin II signaling pathway on the morphology and actin cytoskeleton of SH-SY5Y cells. Immunofluorescent staining for F-actin of FS-2D cells growing on flat substrates and N2D cells or 3D cells cultured on 100–20 μm pattern for 24 h with or without Y-27632 (d–f) and blebbistatin (g–i) treatment or without any treatment (a–c). Scale bar: 20 μm [ABSTRACT FROM AUTHOR]

Fracture toughness is an important parameter in determining the fracture mechanism of rocks, concretes and other composites, and it is used in performing design and stability analyses. In this study, the aim was to determine the effects of different environmental conditions (dry, saturated, freezing, thermal shock and thermal aging) on fracture toughness and fracture energy values of rocks from three different origins: gabbro, recrystallized limestone and limestone. In the first stage, the physical, chemical, mechanical, mineralogical and petrographic properties of rocks were determined. The material properties of rocks were revealed by physico-mechanical tests, XRD, XRF and petrographic analysis. In the second stage, the rocks were aged by exposing them to pre-determined environmental conditions for a certain period of time and then, semi-circular bending strength tests were applied to the aged rocks. SEM images were taken to determine the effects of different environmental conditions on surface cracks. According to the experimental results, thermal shock, thermal ageing and water saturation conditions led to decreasing fracture toughness, while freezing conditions led to increasing fracture toughness. It was determined that thermal shock was the environmental condition that caused the most weakening. In freezing conditions, it was observed that physico-mechanical properties and fracture toughness values of rocks increased. It was seen that the fracture toughness values of the monomineralic structured samples were more affected by the environmental conditions than the multimineralic rocks. [ABSTRACT FROM AUTHOR]

I make use of the characteristics of more than 6000 rock bands to empirically analyze if and how the stability of their members helps them to get a higher level of success. Bands cover all genres of Rock music (from Country to Punk), and their performance is assessed by having a song ranked in Billboard 100. Analyzing how the turn-over of members of a band affects their performance, it appears that the total number of musicians that left the band (compared to the actual number of musicians) – used as an indicator of instability –positively impacts the probability of a success. This may reveal that more talented musicians tend to be recruited after the departure of founding members, or that new members bring fresh ideas. The latter interpretation is supported by another result, showing that solo artists have a higher probability of success than bands. Finally, I also show that bands that come back to the stage after a split do not perform better. [ABSTRACT FROM AUTHOR]

Due to the complexity of the strata, it is difficult to monitor and identify the disasters induced by rock fractures in the process of mining deep coal resources. This will seriously affect the safety and sustainable mining of coal. Therefore, it is necessary to understand the failure mechanisms and acoustic emission (AE) characteristics of different rocks. In this paper, uniaxial compression tests as well as simultaneous AE monitoring were carried out on four different rocks. The four rocks include yellow sandstone, white sandstone, marble and limestone. The mechanical properties, energy evolution and AE characteristics of different rocks were analysed. It is found that the AE response of rocks is closely related to the damage and fracture process. The more brittle the rock is, the less energy is dissipated before failure, and the less obvious the AE precursor is, and the RA-AF values can effectively characterise the failure modes of different rocks. Finally, the damage models were developed from the perspectives of AE energy and dissipated energy, respectively. The damage model based on dissipated energy can better reflect the stress and damage state of the rock, and the theoretical curves of stress–strain are in good agreement with the measured curves. [ABSTRACT FROM AUTHOR]

VAV2 is an activator of RHO GTPases that promotes and maintains regenerative proliferation-like states in normal keratinocytes and oral squamous cell carcinoma (OSCC) cells. Here, we demonstrate that VAV2 also regulates ribosome biogenesis in those cells, a program associated with poor prognosis of human papilloma virus-negative (HPV−) OSCC patients. Mechanistically, VAV2 regulates this process in a catalysis-dependent manner using a conserved pathway comprising the RAC1 and RHOA GTPases, the PAK and ROCK family kinases, and the c-MYC and YAP/TAZ transcription factors. This pathway directly promotes RNA polymerase I activity and synthesis of 47S pre-rRNA precursors. This process is further consolidated by the upregulation of ribosome biogenesis factors and the acquisition of the YAP/TAZ-dependent undifferentiated cell state. Finally, we show that RNA polymerase I is a therapeutic Achilles’ heel for both keratinocytes and OSCC patient-derived cells endowed with high VAV2 catalytic activity. Collectively, these findings highlight the therapeutic potential of modulating VAV2 and the ribosome biogenesis pathways in both preneoplastic and late progression stages of OSCC. [ABSTRACT FROM AUTHOR]

Background and aims: The way in which roots distribute throughout the critical zone influences soil and critical zone formation, as well as water, nutrient and energy fluxes. Root distributions, however, are also influenced by how the critical zone functions. Rapid vegetation changes offer a valuable setting to disentangle these reciprocal effects, and to observe the early changes that occur in the critical zone and how this affects its evolution. Methods: We took advantage of recent exotic Pinus elliottii stands established over native mountain grasslands, to compare how roots of contrasting plant life forms occupy the soil-saprolite-rock continuum. We combined root count and biomass measurements across 2-m-deep observation pits into the saprolite, coupled with topsoil removal plots describing the coarse root transport system introduced by pines. Results: Pine stands had four-fold more root biomass than grasslands (1.74 vs 0.41 kg of dry matter per square meter) and allocated a greater proportion of their fine roots into the saprolite. Pines also developed a coarse root transport system with profuse superficial lateral roots and irregularly distributed sinker roots occupying deep cracks for the first time. Conclusion: The establishment of exotic pines over grasslands reshaped and expanded the root zone in only four decades, highlighting the capacity of vegetation to rapidly change the occupancy and dynamics of the critical zone. [ABSTRACT FROM AUTHOR]

Rock fragment size is a key variable in several mining stages such as underground mine design, equipment selection, and mineral processing. In Block Caving, rock fragment sizes are affected by fragmentation during gravity flow in the ore column while ore is being extracted from drawpoints. Additionally, smaller fragments can percolate between large fragments during gravity flow. These two phenomena — rock fragmentation and particle percolation — are not easy to simulate at a large scale in Block Caving. In this paper, a fragmentation model in a cellular automata gravity flow simulator is proposed to model rock fragmentation during flow at large scales. The fragmentation model uses the rock strength, vertical stresses, and travel distance as inputs to estimate the rock breakage and was calibrated with experimental and mine data. The mine scale results show an error of 9% and 7% of the fragmentation in the zones evaluated. This error rate is considered low due to the variability of the phenomena involved. Then, integrating a fragmentation model into a gravity flow simulator can more realistically represent ore fragmentation in caving-mine to generate flow simulations. [ABSTRACT FROM AUTHOR]

During in vitro culture, human pluripotent stem cells (hPSCs) often acquire survival advantages characterized by decreased susceptibility to mitochondrial cell death, known as “culture adaptation.” This adaptation is associated with genetic and epigenetic abnormalities, including TP53 mutations, copy number variations, trisomy, and methylation changes. Understanding the molecular mechanisms underlying this acquired survival advantage is crucial for safe hPSC-based cell therapies. Through transcriptome and methylome analysis, we discovered that the epigenetic repression of CHCHD2, a mitochondrial protein, is a common occurrence during in vitro culture using enzymatic dissociation. We confirmed this finding through genetic perturbation and reconstitution experiments in normal human embryonic stem cells (hESCs). Loss of CHCHD2 expression conferred resistance to single cell dissociation-induced cell death, a common stress encountered during in vitro culture. Importantly, we found that the downregulation of CHCHD2 significantly attenuates the activity of Rho-associated protein kinase (ROCK), which is responsible for inducing single cell death in hESCs. This suggests that hESCs may survive routine enzyme-based cell dissociation by downregulating CHCHD2 and thereby attenuating ROCK activity. These findings provide insights into the mechanisms by which hPSCs acquire survival advantages and adapt to in vitro culture conditions. [ABSTRACT FROM AUTHOR]

This study has carried out three-dimensional nonlinear elastoplastic analyses to understand the behaviour of tunnels constructed in rock having reinforced concrete lining when subjected to impact loading. The Lagrangian analysis tool has been used to create geometry and mesh the different parts of the present rock tunnel model through Abaqus/Explicit software. 3D lagrangian elements have been used to model the rock and concrete lining. The hoop and longitudinal bars of the reinforcement cage have been modelled using a beam element. The impact resistance behaviour of rock tunnel constructed in three different stages of weathered Quartzite has been simulated to understand the stability characteristics of the tunnel. The three-dimensional missile has been considered a rigid material to incorporate the maximum penetration in the rock when it hits the tunnel surface from 100 m. The four different missile weights i.e. 50 kg, 100 kg, 150 kg and 200 kg have been considered to contemplate the extent of deformation and damage In the tunnel. Moreover, the effect of overburden depth variation has been incorporated in terms of H/D ratio, which is defined as the ratio of overburden depth to diameter of the tunnel. The Ducker-Prager constitutive model with strain-rate dependence and dynamic increase factor is considered to simulate the behaviour of Quartzite rock. Johnson-Cook material model is used for steel bars of reinforcement cage and Ducker-Prager model with strain-rate and dynamic increase factor has been considered for reinforced concrete lining of the tunnel. The analyses results were studied for deformation, particle velocity, particle acceleration and damage in rockmass surrounding the tunnel and its reinforced concrete lining. It has been observed that reinforced concrete lining experiences a significant amount of compression and tension damage at the crown of the tunnel and this damage remains concentrated in the middle one-third section of tunnel length irrespective of change in weight of missile and H/D ratio. It has been concluded that a slightly weathered Quartzite rock tunnel has 18% more impact resistance than a medium weathered rock tunnel and 41% from a highly weathered rock tunnel. Moreover, the particle velocity is found to be inversely proportional to the strength of the surrounding rockmass. Further, particle acceleration generated due to impact loading changes proportionally with the rise in the degree of weathering in rocks. Also, it has been concluded that rock tunnels having a H/D ratio of 2.0 has 4-times higher impact resistance in terms of tension damage than the rock tunnels having a H/D ratio of 0.5. [ABSTRACT FROM AUTHOR]

Due to the differences in techniques between the shield method and the mining method, it is not appropriate to directly draw from the relevant research results and experience of the mining method to calculate the surrounding rock pressure on shield tunnels. And the whole-soil column theory and the Terzaghi theory are only applicable to soft soil strata. Therefore, based on the theory of elasticity and construction characteristics of the shield method, this study has explored the surrounding rock pressure on the shield segment structure in rock strata. Based on the NATM and the ADECO-RS, the impact of the synchronous grouting layer, and the thick-walled cylinder theory, we have established the relationship among the surrounding rock, the synchronous grouting layer, and the segment and obtained the formula to calculate the surrounding rock pressure acting on the shield segment structure in rock strata. Additionally, we took the shield tunnels with moderately weathered and lightly weathered mixed granite on a road tunnel as the research targets and adopted the analytical method to calculate the surrounding rock pressure, which is 0.276 γ H and 0.192 γ H , respectively. [ABSTRACT FROM AUTHOR]

The activities of quarrying in Ebonyi State have resulted in the loss of soil nutrients and an increase in soil pollution. This paper examines the environmental impact of quarrying on soil quality in the three zones of Ebonyi State, south-eastern Nigeria. To achieve the main aim of the study, three objectives were set: access the environmental impact of quarrying on the soil quality of the three zones of Ebonyi district; examine the physico-chemical properties of the soil; and evaluate the environmental impact of quarrying on the heavy metal content of the soil. The auger and core samples were collected at a depth of 20 cm to obtain physicochemical soil properties and heavy metal content. The generated data were subjected to factor analysis, which consists of a correlation matrix, KMO and Bartlett's test, communalities, total variance, scree plot, and component matrix. The major results showed that quarrying has significantly negatively impacted the soils of the three zones of Ebonyi State, as it has led to distortions in soil quality. The results also proved that soil quality within 0–50 m of quarry sites was found to be poorer than in the control area. Positive correlation matrix studies between the quarry locations revealed a common origin of pollution and the negative impact of quarry activities on soil. Based on the results, the study strongly recommends that such soils not be used for agricultural production unless remediation methods are in place, such as bioremediation, soil washing, and thermal desorption. [ABSTRACT FROM AUTHOR]

Understanding the response mechanism of multiparameter rock fractures can improve the accuracy of crack diagnosis. In this study, three types of rock samples with notches were subjected to three-point bending tests. The fracture morphology was observed using scanning electron microscopy, and real-time resistivity and acoustic emission (AE) data were used to describe the crack propagation. The spatial distribution of the electric potential was simulated based on practical crack morphologies and can explain the correlation between rock fracture and rock resistivity or AE. The results reveal that the initiation and propagation of cracks reconstructs the electrical potential distribution characteristics of the rock samples and changed their overall resistivity. The crack growth rate was proportional to the rate of increase in the resistivity rate, and the resistivity increased with nonuniform crack growth. Crack geometry complexity affected circuit connectivity, and a higher resistivity change rate was typically caused by cracks with more uniform propagation. The resistivity variation had the same trend as the fracture toughness, whereas the AE energy exhibited a similar trend to the fracture energy evolution. The cumulative AE count of the granite fracture was the largest, and the peak AE count of coal was larger than that of sandstone. In the main frequency band of 100 ± 25 kHz, a relatively large AE event occurred during crack initiation, and the AE amplitude of granite was the largest. The primary fracture propagation increased the peak AE count, amplitude, energy, and fracture energy release efficiency. During rock fracture, the opening of a microscopic bedding plane and a matrix fracture results in time-varying resistivity and AE characteristics. The complementary electrical and acoustic parameters help describe the details of crack propagation behaviour. Highlights: Cracks restructure the electrical potential distributions in rock samples and change the resistivity. The acoustic emission (AE) energy exhibits a similar trend to the fracture energy evolution. The relationship between the resistivity and AE is mutually verified and complementary. [ABSTRACT FROM AUTHOR]

This article considers the issues of resource conservation and integrated development of deposits, as well as their involvement in the processing of ore rocks, such as gabbro-diabase of the Bazhenov deposit, which has reduced the environmental burden and the costs of dumping and reclamation. Melting of gabbro-diabase of the Bazhenov deposit makes it possible to obtain a new product, i.e., basalt (rock) wool, which is a good heatproof, soundproof, and fireproof material for the construction industry. Based on this material, a unique hydroponic substrate is produced, which is widely used in agriculture. Increasing the complexity of processing mineral resources is an opportunity to obtain additional profit for the enterprise from new types of products. [ABSTRACT FROM AUTHOR]

The direct assessment of uranium in rock, soil, and fruits has been documented using a simple, quick, cost-effective, accurate, and precise LED fluorimetry approach. Studies utilizing various fluorescence-enhancing reagents, such as sodium pyrophosphate and orthophosphoric acid, are conducted to determine the effects exerted on the uranium fluorescence by several common major, minor, and trace elements that are predicted to be present in various geological formations. The uranium content (ppb) in the area ranges from 2.138 to 2.88 (soil), from 0.571 to 0.585 (rock), and from 0.22 to 0.28 (fruits). Iron in concentrations higher than 100-fold uranium concentration quenches the uranium fluorescence. Before being determined by LED fluorimetry, iron is removed from the uranium sample by solvent extraction using ethyl acetate and 2,3-dihydroxynaphthalene. This technique was used to accurately and reliably determine the presence of uranium in rocks, soil, and fruits. [ABSTRACT FROM AUTHOR]

Groundwater study is interdisciplinary in nature. To understand groundwater, it is essential to be informed about the lithology of the study area. In this article rock types existing in entire India have been thoroughly discussed. It has also been discussed the depth of the water level in the aquifers of the eastern part of India which is quite high compared to its western counterpart both in the pre-monsoon as well as post-monsoon periods. It has discussed the groundwater availability and groundwater draft in the entire India. The annual available groundwater level in West Bengal is very high but the groundwater draft is also quite large there. Since there is continuous freshwater scarcity in the Purba Medinipur coastal locality in West Bengal, it has been taken as the study area. Precipitation is also quite high in Purba Medinipur. The groundwater level has declined due to the progress over time. Population increase in Purba Medinipur is ~ 0.75% per annum which is very high resulting in groundwater level decline. A total of 87 specimens of water were procured by Public Health Engineering Directorate in the years 2017-18 from the study area. The tested water quality results of all these samples were examined in this study. The concerned area is declared as saline prone area. Groundwater contamination in the concerned area has been found out. On that basis the present condition several preventive measures have been suggested among which hybrid technology is suggested to be the best. [ABSTRACT FROM AUTHOR]

The Clarion Clipperton Fracture Zone (CCZ) in the northeast Pacific is a heterogeneous deep-sea environment, featuring abyssal plains as well as multiple seamounts and abyssal hills (bathymetric elevations) that harbour a highly diverse megabenthic fauna. Based on the analysis of seafloor photographic transects that were taken from elevated areas downslope into the abyssal plains in the eastern CCZ, a similar distribution of habitats was observed on five different bathymetric elevations including abyssal hills as well as the foothills of two seamounts. Rock outcrops occur at the summits, surrounded by an area with varying coverage and size of polymetallic nodules, which were divided into two different habitats characterized by large and small nodules, respectively, and followed by nodule-free sediments. Megafauna composition, density and diversity varies across these habitats. While density is the highest in areas with rock outcrops (1.4 individuals per m2), the biodiversity is the highest when regarding all of the habitats combined. Regarded individually, nodule-covered areas are the most diverse, whereas sediment areas without hard substratum, i.e. nodule free sediments, show the lowest biodiversity and the lowest density (0.2 individuals per m2). The multinomial species classification method (CLAM) shows that most of the observed megafauna morphotypes have to be regarded as rare. The large differences between the megafaunal communities at bathymetric elevations and the abyssal plain reported from previous studies might partly be explained by the multiplicity of habitats. This high heterogeneity can lead to a more diversified community at elevations, although most habitats can also be observed in the abyssal plain. [ABSTRACT FROM AUTHOR]

The Anthropocene has been observed as an opportunity to generate new legal imaginaries capable of revising incumbent assumptions of legal and political thought. What opportunities do such ambitions afford for communication between geological and legal thought? Responding to Birrell & Matthews attempt to 're-story a law for, rather than of, the Anthropocene,' I wish to describe some ways in which the Anthropocene Working Group, who are pursuing formalisation of the Anthropocene as an official geological unit, are involved in a similar exercise of re-storying geology. The Anthropocene theme is brought to bear as a geological reality through material practices of measurement and correlation, as well as through the invocation of previous judgements of the evaluative committees associated with the formalisation of new geological unit. This effort amounts to a redefinition of the practices of geological observation, i.e. what counts as geologically relevant and why. In keeping with the theme of an 'ethics of encounter', as encouraged by Birrell and Matthews, this article suggests that the AWG's effort provides a model with which the elaboration of 'laws for the Anthropocene' might correspond. [ABSTRACT FROM AUTHOR]

Highlights: The experimental survival probability of one irregular shaped rock was established via 105 drop tests using mortar replicas. The derivation and validation of an analytical model to predict the survival probability of brittle rocks of irregular shape upon collinear impact is presented. The survival probability predicted by the model was found to fall withing 5% of the experimental data with an excellent goodness of fit coefficient (R2 ~ 93%). [ABSTRACT FROM AUTHOR]

The wear of functional components of rock-crushing tools with composite diamond-containing materials (DCM) based on a metal binder sintered by resistive electrosintering under pressure in the process of grinding of sandstone from the Torez deposit is studied. A characteristic named the degree of reinforcing of the working surface of the DCM functional components is proposed, which is determined from the ratio of the total area of the diamond cutting grains to the area of the working surface of the functional component. The dependence of the intensity of wear of DCM functional components on the degree of diamond reinforcement of their working surfaces is plotted. During the tests, rock destruction products and wear (sludge) fragments of DCM functional components are collected and analyzed using digital image processing tools, as a result of which morphometric characteristics of the sludge as a function of the degree of reinforcement of the DCM component working surfaces with diamond grains are obtained. Using the colorimetry method, metal binder fragments of the DCM are isolated from the total mass of sludge and their size distribution is determined. The results of morphometric analyses of the wear products of the diamond-containing composite tool and the rock destruction products are given. [ABSTRACT FROM AUTHOR]

A hydraulic splitting method was recently developed to reduce the generation of noise and vibration in urban underground construction. However, research on optimizing the method considering the shape of the hydraulic splitting machine or the rock type has yet to be conducted sufficiently. Herein, experimental and numerical investigations were conducted to identify the crushing performance of six types of bit heads on three kinds of rocks (granite, marble, and sandstone). The uniaxial and triaxial compressive test, Brazilian test, and semicircular bend (SCB) test were conducted to investigate the physical properties of the rocks. Simultaneously, the splitting fracture of the rocks was investigated depending on the shape of the bit head. The test results showed that the failure of the specimens was controlled by the tensile strength of the rock, while the failure mode was governed by the type of the bit heads. Based on the test results, a damage-plasticity model was used to simulate the failure test by introducing double damage variables. Consequently, the numerical simulations effectually replicated the failure modes of the splitting fracture of the rock samples by the different bit heads. [ABSTRACT FROM AUTHOR]

The failure characteristics of geotechnical materials are quite complex, among which there are obvious differences between soil materials and rock materials. In order to describe the failure characteristics of soil materials and rock materials uniformly, a new failure and yield criterion, called VML criterion, is proposed in this paper. This strength criterion has the following characteristics. (1) On the deviatoric plane, the criterion can be expressed as a power parameter expression of von Mises criterion and spatial mobilized plane (SMP) criterion, so it can be used to describe cohesive materials such as metals or frictional materials such as sand. (2) On the meridian plane, another power parameter expression can be used to consider tensile stress strength. On the meridian plane, the material strength envelope can be expressed as a curve, so the hydrostatic pressure effect of soil material can be reasonably considered. (3) In order to consider the volumetric compression yield properties of soil materials under isotropic compression, a yield criterion considering the volumetric compression yield properties is also proposed on the deviatoric plane. Since geotechnical materials are often in plane strain condition in engineering, a VML criterion expression considering plane strain condition is proposed in this paper. The criterion shows that the internal friction angle of soil under plane strain is usually 1.1 times of that under conventional triaxial compression. The comparison between the predicted and tested data shows that the VML criterion proposed in this paper can be widely applied to the failure simulation of rock and soil materials, and the plane strain VML criterion can also be applied to the failure prediction with plane strain state. [ABSTRACT FROM AUTHOR]

The processes of biodeterioration of the unique Tomskaya Pisanitsa monument of rock art in Western Siberia have been studied by a complex of biological and mineralogical methods. The species composition of the lithobiotic community (bacteria, fungi, and lichens) is identified using a complex of cultural, morphological, and molecular genetic methods. It is shown that the destruction of the monument is a result of interrelated physical, chemical, and biological processes, accompanied by a change in the properties of the rock and its biological colonization. The structure of microbial communities depends on the local environment and successional processes. The development of biofilms with the dominance of cyanobacteria is observed on the rock zones of increased moisture and the formation of carbonate crusts. The problems of adaptation of the lithobiotic microorganisms to existence at the Tomskaya Pisanitsa rock art monument, as well as their role in the processes of oxalate and carbonate biomineralization, are discussed. The results point to the danger of deterioration of Tomskaya Pisanitsa monument and indicate the need to find new effective ways to protect it, taking into account the accumulated scientific data. [ABSTRACT FROM AUTHOR]

The work is devoted to the development of an electric pulse method for processing rocks and other solid dielectric and semiconducting materials. For the first time, experimental studies of the electric pulse method of cutting rocks in water were carried out using a high-voltage pulse generator with a pulse repetition rate of up to 25 pulses per second and a voltage of up to 160 kV. The results showed the possibility of using high-voltage generators with low pulse energy and high repetition rate in the electric pulse technology when using water as a flushing liquid. At the same time, the used mechanical system for moving the electrodes and washing needs to be improved to increase the productivity of electric pulse processing. [ABSTRACT FROM AUTHOR]

The problem of proper assessment of the technical functionality of rock bolt support systems is still valid. Many research centers have undertaken efforts to diagnose and monitor the technical state of such a support system used in mines and tunneling. With that aim the method of quality assessment of grouted rock bolts was invented and a relevant apparatus was constructed. The method concerns non-destructive identification of discontinuity of a resin layer (grout) surrounding rock bolts. The method is based on an impact excitation of a rock bolt and uses modal analysis procedures. Assuming that the installed rock bolt acts as an oscillator, different lengths and positions of grouting discontinuity alter its modal parameters. The extraction of these modal parameters, of which a resonant frequency is seen as the most valued, enable the relevant identification of grout discontinuity. After constructing a prototype version and validating the results for known cases of resin discontinuity in an experimental coal mine, the apparatus fulfilling ATEX requirements was developed. Subsequently that version was also verified both in laboratory conditions and in an experimental coal mine. As necessary for proper identification of discontinuity length, the reference data base was developed and elaborated consisting of a very large number of finite element models (FE models), namely discontinuity cases. The models encountered different rock bolt lengths and diameters, different rock strata parameters and different positions and lengths of resin layers. Then the method was used in a working coal mine to monitor a technical state of rock bolt support system mounted to reinforce long underground openings. The data base was utilized as reference for investigated rock bolts. [ABSTRACT FROM AUTHOR]

In this paper, the Pull-Off Test (POT) was analyzed as a method for determining the mode I fracture toughness (KIc) of rock and concrete. POT is submitted to tensile load (which causes a simpler stress state than tests submitted to bending and compression load) and its execution is easy, replicable and can be performed in laboratory and in situ (being its great advantage). A ratio between the dimensions of the POT was proposed to meet the Linear Elastic Fracture Mechanics requirements and the POT literature recommendations. Parametric studies were performed using numerical analysis and it was concluded that the POT is suitable for KIc testing, since mode I prevails in the test, and an equation was proposed for determining KIc in homogeneous rock and concrete (micro-concrete and mortar). A practical example of the method application was provided and KIc was determined for some homogeneous rocks. A similar result was achieved between POT and Semi-Circular Bending test. Highlights: The Pull-Off Test was analyzed as a method for determining the mode I fracture toughness of rock and concrete. The execution of the Pull-Off Test is easy, replicable and can be performed in laboratory and in situ. A ratio between the dimensions of the Pull-Off Test was proposed. The Pull-Off Test is suitable for mode I fracture toughness testing, since mode I prevails in the test. An equation was proposed for determining the mode I fracture toughness via Pull-Off Test of homogeneous rocks and concretes (micro-concrete and mortar). [ABSTRACT FROM AUTHOR]

Highlights: Anapparatus with precise controllability and large stiffness was designed to investigate the mechanical behavior of rock grain interface. The fracture toughness and tensile strength of the rock GI are scattered and follow an exponential probability distribution function. The validity of the obtained grain interface strength parameter was verified by a numerical model. [ABSTRACT FROM AUTHOR]

In the past two decades, the visualization experiment technology for transparent geotechnical materials has developed into a method of observing deformation, fluid flow and other internal changes of rock and soil. This paper reviews the emergence and development of transparent rock-soil experiment technology, the preparation for different kinds of transparent geotechnical materials, the experiment equipment, the optical observation method, and the engineering application of this technology. In the traditional physical similarity experiment, the deformation law and the diffusion process of fluid flow cannot be observed directly because of the opaque medium. Therefore, a large number of scholars combined with optical measurement means and digital image processing technology to study the deformation and fluid flow in the rock and soil. Compared with the physical similarity experiment, this technique not only can realize the visual observation of geotechnical engineering change process, but also has the advantages of involvement of simple device, easy operation and low cost. It is also pointed out that it is in urgent need of establishing technical standards for the preparation of transparent rock-soil samples and the determination of engineering property indexes. [ABSTRACT FROM AUTHOR]

This paper has proposed a new perspective of studying internal structure-based tests, the results of which will improve the present experimental methods and enrich our understanding of rock structure-based modeling without any core preparations, with low cost in a short time. Pore volume compressibility (PVC) is an important feature of rock and is related to mechanical and structural behavior of porous rock sample. An accurate evaluation of pore volume compressibility depends on experimental test which is time-consuming and costly. This paper outlines new method for evaluation of PVC of rock cores using a computed tomography (CT) scan-based finite element method (FEM). The verification studies were performed on a series of porous rock cores which were extracted from deep oil reservoirs in Iran. In order to construct a finite element model, a relationship between spatial elastic properties of samples and CT-scanned data images was derived. The samples were scanned by a conic beam computed tomography (CBCT) machine, and the scanned data were converted into a model to simulate PVC tests. The pore volumetric strains were obtained from a linear elastic analysis for each stress and pore pressure step. To validate the finite element analysis (FEA) results, a series of experimental PVC tests were conducted on the pre-scanned samples and PVC curves were extracted. As a result, the predictions calculated from the CT scan-based numerical models have shown a good correlation with the results obtained from laboratory experiments. The results revealed that it is possible to simulate PVC tests using this numerical proposed evaluation method in such a way that the cost and time of the tests were lowered. [ABSTRACT FROM AUTHOR]

The ultimate seismic bearing capacity problem of strip foundations under eccentric loading is investigated within the framework of limit analysis theory. Referring to the kinematic approach formulated in the context of pseudo-static method, the analysis aims to assess the reduction in bearing capacity induced by the combined effects of load eccentricity and seismic loading. At the material level, the generalized Hoek–Brown failure criterion is adopted for modeling the nonlinearity of the strength properties. At that respect, derivation of closed-form expressions for the support functions associated by duality with such a failure condition is a fundamental component for the implementation of the kinematic approach. At the structure level, elaboration of two specific failure mechanisms allows deriving rigorous upper bound estimates for the ultimate bearing capacity. The approach is then applied to assess the effects of relevant geometry, strength, and loading parameters controlling the stability conditions. The accuracy of the analysis is evaluated by comparison with a series of lower and upper finite element solutions, thus emphasizing effectiveness of the approach to predict the reduction in ultimate bearing capacity associated with the particular loading conditions. [ABSTRACT FROM AUTHOR]

Changes in apparent electrical resistivity are calculated using one of the electrical survey methods—the median gradient—over the earthquake nucleation area in the shape of a sphere. Changes in the specific electrical resistivity of rocks in the source region of the earthquake nucleation are estimated taking into account the published estimates of changes in strain and strain-sensitivity coefficients. We consider the models where the sphere-shaped inclusion has a constant size in time and its electrical conductivity and depth of occurrence increase. Also considered is a model where the depth of the sphere is constant and the resistivity of the rocks in it decreases. A model is presented in which the size of the inhomogeneity increases with a simultaneous decrease in the electrical resistivity of rocks in it and the further localization of the decrease in a smaller volume, which corresponds to the ideas of tightening the nucleation zone of the main rupture into a narrow zone. According to this model, the graphs of changes in apparent resistivity return to background values shortly before the earthquake, i.e., changes in apparent resistivity over time will have the shape of a bay. A comparison of changes in electrical resistivity according to this model with variations in the resistivity of rocks at the Ashgabat Geodynamic Survey site, as well as limestone samples under laboratory conditions during their deformation and destruction, show their qualitative similarity and the possibility of using the results of laboratory tests of samples for modeling and analyzing the process of earthquake nucleation. [ABSTRACT FROM AUTHOR]

The radioactivity levels of natural radionuclides 226Ra, 232Th, and 40K in the rocks of Dakshina Kannada region of southern India were measured by NaI (Tl) gamma-ray spectrometer. The specific activities of 226Ra, 232Th, and 40K ranged from 4.2 ± 0.4 to 74.5 ± 1.7 Bq kg−1, 14.5 ± 0.7 to 83.5 ± 1.6 Bq kg−1, and 172 ± 3 to 964 ± 7 Bq kg−1 with the mean of 25.1 ± 1.0 Bq kg−1, 36.1 ± 1.0 Bq kg−1, and 502 ± 5.0 Bq kg−1, respectively. The normality of the frequency distribution curves of 226Ra, 232Th, and 40K was tested using the Kolmogorov–Smirnov test. The radiological hazard indices were computed from the measured activity concentration of natural radionuclides in rocks and these were found to be within acceptable levels. To investigate the sources of radioactivity, the minerals involved in the rocks were detected using XRD and FTIR. The mineralogical studies reveal that the principal sources of gamma radiation in the study area are 232Th-rich phosphates and 40K-bearing feldspars. [ABSTRACT FROM AUTHOR]

Osteochondritis dissecans (OCD) describes a pathologic condition centered at the osteochondral junction that may result in an unstable subchondral fragment (progeny), disruption of the overlying cartilage, which may separate from the underlying parent bone. It is one of the causes of chronic knee pain in children and young adults. The current literature on OCD lesions focuses primarily on the medial femoral condyle (MFC), but inconsistent use of terminology, particularly in the distinction of OCD lesions between skeletally immature and mature patients has created uncertainty regarding imaging workup, treatment, and long-term prognosis. This article reviews the pathophysiology of MFC OCD lesions, highlighting the role of endochondral ossification at the secondary growth plate of the immature femoral condyles, the rationale behind the imaging work-up, and key imaging findings that can distinguish between stable lesions, unstable lesions, and physiologic variants. This overview also provides a case-based review to introduce imaging correlates with the ROCK (Research in Osteochondritis of the Knee) arthroscopic classification. [ABSTRACT FROM AUTHOR]

The fatigue damage evolution of rocks subjected to cyclic loading and unloading has always been a hot spot that receives worldwide attention in the field of rock mechanics. Recent studies that rely on advanced nondestructive testing (NDT) techniques enable accurate monitoring and assessment of the dynamic damage in cyclically loaded rocks, and well contribute to revealing the complicated failure mechanism. These works are critical to ensure safe underground tunnelling and mining activities. As a promising NDT technique, the electromechanical impedance method (EMI) has been successfully applied to many aspects in structure health monitoring. In this paper, the EMI method was extended to measuring the rock fatigue damage. Firstly, uniaxial cyclic compression tests with increasing amplitude were performed on three types of cylindrical rock specimens, including sandstone, granite and carbonaceous shale. The varying mechanical properties and energy conversion characteristics were analyzed. In particular, the damage evolution characterized by elastic energy dissipation was determined. Concurrently with cyclic tests, conductance signatures in response to two excitation modes of the surface-bonded piezoelectric transducers were collected, and the spectral localized and overall variations were analyzed. It is discovered that the resonant frequency shift and the statistic metric MAPD within the transverse mode-dominated frequency range could accurately indicate the rock fatigue damage. This research sufficiently confirms the effectiveness and reliability of the EMI method in quantifying the accumulative damage of different rocks under uniaxial cyclic loading and unloading. [ABSTRACT FROM AUTHOR]

Purpose: Metastasis is a major leading cause of mortality in female breast cancer (BrCa). Cellular motility is a pathological process of metastasis remarked by the overexpression of cortactin (CTTN), Ras homolog family member-A (RhoA), and Rho-associated kinase (ROCK) genes. Their balance is responsible for upholding the integrity of healthy epithelial cell junctions. This study aimed to explore the associations between a posteriori dietary patterns and the expression levels of pro-metastatic genes in primary BrCa. Methods: In this consecutive case series, 215 eligible women, newly diagnosed with histologically confirmed non-metastatic BrCa (stage I-IIIA), were recruited from Hospitals in Tabriz, Northwestern Iran (2015–2017). The tumoral expression levels of genes were quantified using real-time reverse transcription-polymerase chain reaction. Dietary data assessment was carried out using a validated food frequency questionnaire. Results: Three dietary patterns were identified using principal component analysis (KMO = 0.699). Adherence to the "vegan" pattern (vegetables, fruits, legumes, nuts, seeds, and whole grains) was inversely associated with the expression levels of RhoA (ORAdj.T3vs.T1 = 0.24, 95%CI 0.07–0.79) and ROCK (ORAdj.T3vs.T1 = 0.26, 95%CI 0.08–0.87). In addition, the highest adherence to the "prudent" pattern (spices, seafood, dairy, and vegetable oils) decreased the odds of overexpressions at RhoA (ORAdj.T3vs.T1 = 0.26, 95%CI 0.08–0.84) and ROCK genes (ORAdj.T3vs.T1 = 0.29, 95%CI 0.09–0.95). The highest adherence to "Western" pattern (meat, processed meat, hydrogenated fat, fast food, refined cereals, sweets, and soft drinks) was a risk factor associated with the overexpression of RhoA (ORAdj.T3vs.T1 = 3.15, 95%CI 1.12–8.85). Conclusion: Adherence to healthy dietary patterns was significantly associated with the downregulation of pro-metastatic genes. Findings provided new implications to advance the nutrigenomic knowledge to prevent the odds of over-regulations in pro-metastatic genes of the primary BrCa. [ABSTRACT FROM AUTHOR]

Depending on the type of failure mechanism, the strength of intact rock may be susceptible to the effects of scale. The influence of scale is apparent in the spalling of rock around underground openings. To reconcile field-scale observations, an understanding of the unconfined rock strength has to be appreciated from the standpoint of energy instability, particularly for instances in which the mechanism of failure involves propagation of fractures. Fracture energy principles were used to create a link between laboratory-measured uniaxial compressive strength (UCS) and rock failure as observed in spalling around circular openings. An Instability Line (IL) is proposed to predict the stresses above which spalling could occur with different opening diameters. Good comparisons were obtained for a range of dimensions from small boreholes to large tunnels. Based on field observations and analytical study, the results suggest that two conditions are required for spalling to occur. The first is that the crack initiation stress has to be exceeded, and the second is that the stress needs to be above the IL. The findings suggest that the effects of scale are limited by the crack initiation stress. For large-diameter openings, instability occurs immediately at crack initiation stress, whereas for smaller-diameter openings instability occurs at higher stresses post-crack initiation stress. Highlights: This paper aims to explain the discrepancies in the rock mechanics literature to predict spalling for small-diameter boreholes as against large-diameter tunnels. The failure mechanism of spalling is studied based on the framework of energy stability. An Instability Line is proposed based on the analytical study. The results of the analytical study compared well with published laboratory and field observations. The results suggest that two conditions are required for spalling to occur. The first is that the crack initiation stress has to be exceeded, and the second is that the stress needs to be above the Instability Line. The findings suggest that the effects of scale are limited by the crack initiation stress. [ABSTRACT FROM AUTHOR]

Prediction of strain is one of the important factors for assessment of characteristics of rock material. Rock strata are mostly more brittle in nature. Most of the natural ground vibrations are caused due to release of the strain energy stored in the rock strata. The strain governs the development of crack pattern and failure of rock strata. This sudden failure of rock strata may lead to catastrophic disaster. This paper investigates to develop a new prediction approach of strain in rock sample using Artificial Neural network (ANN) with optimization techniques, namely Equilibrium Optimizer (EO), Differential Evolution (DE), Grasshopper Optimization Algorithm (GOA) and Whale Optimization Algorithm (WOA). For this purpose, a total of 3000 data with input and output data are collected from experimental investigations carried out in the laboratory. In this study, the strains are predicted in lateral and longitudinal dimension of the rock sample. The accuracy of the proposed prediction models, ANN-EO, ANN-DE, ANN-GOA and ANN-WOA, is studied by using different statistical indices. Furthermore, the proposed models are assessed for selecting the robust model for accurate prediction of rock sample by using boxplot, accuracy matrix, Taylor diagram, rank analysis, Objective Function (OBJ) Criterion, Akaike Information Criterion (AIC), Developed Discrepancy Ratio (DDR) criterion, external validation, and uncertainty analysis. The results show that the ANN-EO model outperforms other proposed models in the training and testing stages. The OBJ of ANN-EO and ANN-DE for lateral strain modelling are 0.065 and 0.064 respectively, while, for longitudinal strain modelling, the ANN-EO and ANN-WOA work best with OBJ of 0.037 and 0.075 respectively. Hence, ANN-EO can be proposed as a robust model when compared to other model for prediction of strain in rock sample. [ABSTRACT FROM AUTHOR]

With the development of 3D printing and computer numerical control machining techniques, extremely complicated models physically simulating the underground structures in rock engineering were conducted. Whether these artificial materials can accurately simulate the cracking and failure modes of natural rocks should be studied. The present study uses an artificial material-moulded gypsum to compare with the mechanical behaviours of natural marble from the perspective of brittleness. The comparison can provide an insight into the feasibility of the physical simulation. In addition, to investigate the strain rate influence on brittleness with the background of dynamic loading related to rock engineering, the rate dependence of the brittleness is investigated considering the size effect. Six types of brittleness indexes proposed in the quasi-static loadings are studied under various loading rates with strain rates ranging from 10–6 to 103 s−1. The result indicates that not all the brittleness indexes are applicable in the dynamic regime. Two brittleness indexes are suggested to evaluate the dynamic gypsum brittleness due to its reasonable depiction of real dynamic brittleness. Gypsum is more brittle than marble under both quasi-static and dynamic loadings based on the analysis of brittleness indexes and cracking behaviour. Meanwhile, the experimental and numerical results confirm the influence of the brittleness of material on the cracking behaviours and imply that the artificial material should be assessed to ensure the validity and feasibility before the physical simulation of rock structures in engineering. Highlights: The brittleness of 3D printing material in physical simulation should be considered. The dynamic brittleness of gypsum and marble is compared. The brittleness indexes are extended into the dynamic condition. Brittleness index can affect the cracking behaviour. The feasibility of 3D printing in rock mechanics should be evaluated before experiments. [ABSTRACT FROM AUTHOR]

Given the major impact of thermal treatment on the deformation and failure characteristics of rocks in deep rock engineering, it is crucial to understand the relevant behaviors of rocks with the temperature effect being taken into account. For this purpose, the deformation of rocks after exposure to high temperature is divided into void and skeleton portions based on the deformation analysis of rock mechanics. Then, a constitutive statistical model for rocks is established by assuming that the probability density function of the stress level of rock mesoscopic elements is consistent with normal random distribution, and the thermal damage variable is introduced. The theoretical results of the thermal damage deformation model based on characteristics of the void compaction stage are well in line with experimental data from conventional compression tests of Nanan granite after high temperature. Optical microscopy shows that the obvious void compaction stage is related to the propagation and development of original and initiated microcracks. Compared to the classic damage model, the improved model better captures the void compaction stage of the strain–stress curves of granite after high temperature. The extreme value method was used to determine the normal statistical distribution parameters based on conventional rock mechanical tests. This theoretical model is therefore convenient in engineering applications involving high-temperature effects. [ABSTRACT FROM AUTHOR]

The small monomeric GTPase RHOA acts as a master regulator of signal transduction cascades by activating effectors of cellular signaling, including the Rho-associated protein kinases ROCK1/2. Previous in vitro cell culture studies suggest that RHOA can regulate many critical aspects of vascular endothelial cell (EC) biology, including focal adhesion, stress fiber formation, and angiogenesis. However, the specific in vivo roles of RHOA during vascular development and homeostasis are still not well understood. In this study, we examine the in vivo functions of RHOA in regulating vascular development and integrity in zebrafish. We use zebrafish RHOA-ortholog (rhoaa) mutants, transgenic embryos expressing wild type, dominant negative, or constitutively active forms of rhoaa in ECs, pharmacological inhibitors of RHOA and ROCK1/2, and Rock1 and Rock2a/b dgRNP-injected zebrafish embryos to study the in vivo consequences of RHOA gain- and loss-of-function in the vascular endothelium. Our findings document roles for RHOA in vascular integrity, developmental angiogenesis, and vascular morphogenesis in vivo, showing that either too much or too little RHOA activity leads to vascular dysfunction. [ABSTRACT FROM AUTHOR]