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To investigate the long-term stability of deep rocks, a three-dimensional (3D) time-dependent model that accounts for excavation-induced damage and complex stress state is developed. This model comprises three main components: a 3D viscoplastic isotropic constitutive relation that considers excavation damage and complex stress state, a quantitative relationship between critical irreversible deformation and complex stress state, and evolution characteristics of strength parameters. The proposed model is implemented in a self-developed numerical code, i.e. CASRock. The reliability of the model is validated through experiments. It is indicated that the time-dependent fracturing potential index (ξTFPI) at a given time during the attenuation creep stage shows a negative correlation with the extent of excavation-induced damage. The time-dependent fracturing process of rock demonstrates a distinct interval effect of the intermediate principal stress, thereby highlighting the 3D stress-dependent characteristic of the model. Finally, the influence of excavation-induced damage and intermediate principal stress on the time-dependent fracturing characteristics of the surrounding rocks around the tunnel is discussed.

The gut has been a focal point in the research of digestive system disorders. The internal microbiota generates metabolites that function as signaling molecules and substrates, interacting with the intestinal wall and influencing host physiology and pathology. Besides, the gut microbiota and metabolites owe highly diverse types and quantities, posing challenges for quantitative analysis, and monitoring frequent interactions between digestive tract metabolites and the intestinal wall remains a challenge. However, research targeting gut microbiota metabolites has elucidated their relevance to digestive diseases. By modulating metabolites such as short-chain fatty acids, bile acids, and lipopolysaccharides, it is possible to intervene in the progression of diseases such as inflammatory bowel disease and non-alcoholic fatty liver disease. Currently, research on gut microbiota is advancing, and more work is required to explore the interactions between host, microbes and underlying mechanisms. In this review, we have revisited the generation of gut microbiota-related metabolites, their impact on diseases, and modes of interaction, emphasizing the significant role of metabolites in digestive system disorders. It is believed that the linkage between gut microbiota and diseases in current research can be established through metabolites, providing a framework and foundation for research in the field of metabolomics and fundamental mechanisms.

The deep surrounding rock is usually in the true triaxial stress state, and previous constitutive models based on the understanding of uniaxial and conventional triaxial test results have difficulty characterizing the degradation and fracture process of rock ductile–brittle failure under true triaxial stress state. Therefore, this study conducted a series of true triaxial tests to obtain the understanding of the ductile–brittle behaviour of rock, and then combined the test results and the Mogi–Coulomb strength criterion, and proposed calculation methods for the elastic modulus E, cohesion c and internal friction angle φ and the evolution functions of E, c and φ of rock under true triaxial stresses. With the decreasing of the minimum principal stress σ3 or increasing of the intermediate principal stress σ2, the marble post-peak stress drop rate gradually increases, the ductility gradually weakens, and the brittleness significantly strengthens. The calculation method and evolution function of rock E, c and φ under true triaxial stress were proposed. E decreased at first and then tended to remain stable with the increasing of equivalent plastic strain increment dεp. c and φ slowly increased at first and then rapidly decreased. With a method of parameter degradation rate to realize post-peak stress drop rate to reflect the ductile–brittle characteristics, a new three-dimensional ductile–brittle deterioration mechanical model (3DBDM) was established. The proposed model can accurately characterize the influence of σ2 and σ3 on mechanical parameters, the ductile–brittle behaviour of rock under true triaxial stresses, and the asymmetric failure characteristics of surrounding rock after excavation of deep underground engineering. The proposed model can be reduced to elastic–perfectly plastic, elastic–brittle, cohesion weakening friction strengthening (CWFS), Mohr–Coulomb, and Drucker–Prager models.

Layered rock mass is a type of engineering rock mass with sound mechanical anisotropy, which is generally unfavorable to the stability of underground works. To investigate the strength anisotropy of layered rock, the Mohr-Coulomb and Hoek-Brown criteria are introduced to establish the two transverse isotropic strength criteria based on Jaeger's single weak plane theory and maximum axial strain theory, and parameter determination methods. Furthermore, the sensitivity of strength parameters (K1, K2, and K3) that are used to characterize the anisotropy strength of non-sliding failure involved in the strength criteria and confining pressure are investigated. The results demonstrate that strength parameters K1 and K2 affect the strength of layered rock samples at all bedding angles except for the bedding angle of 90° and the angle range that can cause the shear sliding failure along the bedding plane. The strength of samples at any bedding angle decreases with increasing K1, whereas the opposite is for K2. Except for bedding angles of 0° and 90° and the bedding angle range that can cause the shear sliding along the bedding plane, K3 has an impact on the strength of rock samples with other bedding angles that the specimens' strength increases with increase of K3. In addition, the strength of the rock sample increases as confining pressure rises. Furthermore, the uniaxial and triaxial tests of chlorite schist samples were carried out to verify and evaluate the strength criteria proposed in the paper. It shows that the predicted strength is in good agreement with the experimental results. To test the applicability of the strength criterion, the strength data of several types of rock in the literature are compared. Finally, a comparison is made between the fitting effects of the two strength criteria and other available criteria for layered rocks.

The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters. However, the mechanical properties and damage/fracture evolution mechanisms of deep rock induced by microdynamic disturbance under three-dimensional stress states are unclear. Therefore, a true triaxial multilevel disturbance test method is proposed, which can completely simulate natural geostress, excavation stress redistribution (such as stress unloading, concentration and rotation), and subsequently the microdynamic disturbance triggering damaged rock failure. Based on a dynamic true triaxial test platform, true triaxial microdynamic disturbance tests under different frequency and amplitudes were carried out on monzogabbro. The results show that increasing amplitude or decreasing frequency diminishes the failure strength of monzogabbro. Deformation modulus gradually decreases during disturbance failure. As frequency and amplitude increase, the degradation rate of deformation modulus decreases slightly, disturbance dissipated energy increases significantly, and disturbance deformation anisotropy strengthens obviously. A damage model has been proposed to quantitatively characterize the disturbance-induced damage evolution at different frequency and amplitude under true triaxial stress. Before disturbance failure, the micro-tensile crack mechanism is dominant, and the micro-shear crack mechanism increases significantly at failure. With the increase of amplitude and frequency, the micro-shear crack mechanism increases. When approaching disturbance failure, the acoustic emission fractal dimension changes from a stable value to local large oscillation, and finally increases sharply to a high value at failure. Finally, the disturbance-induced failure mechanism of surrounding rock in deep engineering is clearly elucidated.

Abstract Objective Personality, emotions, and olfaction exhibit partial anatomical overlap in the limbic system structure, establishing potential mechanisms between personality, affective disorders, and olfactory-related aspects. Thus, this study aims to investigate the associations among the Big Five personality traits, alexithymia, anxiety symptoms, and odor awareness. Methods A total of 863 college participants were recruited for this study. All participants completed the Chinese Big Five Personality Inventory-15, the Odor Awareness Scale (OAS), the Toronto Alexithymia Scale-20, and the Generalized Anxiety Disorder Screener-7. Structural equation modeling was employed to examine the hypothesized mediated model. Results The findings revealed the majority of significant intercorrelations among the dimensions of the Big Five personality traits, alexithymia, anxiety symptoms, and OAS (|r| = 0.072–0.567, p

BackgroundGrowing evidence suggests a link between vitamin K (VK) intake and depression, although the underlying mechanisms remain unclear. We aimed to investigate whether oxidative balance scores (OBS) mediate the association between VK intake and depression in participants from the National Health and Nutrition Examination Survey (NHANES) 2007–2018.MethodsWe analyzed data from 30,408 individuals. Dietary VK intake served as the independent variable, depression symptoms as the outcome variable, and OBS as the mediator. Multivariable logistic regression and restricted cubic splines assessed the associations. Mediation analysis was conducted to evaluate the potential mediating role of OBS.ResultsHigher dietary VK intake was associated with lower depression risk in the multivariate model. Compared to the lowest log2 VK quartile, those in the higher quartiles had significantly lower depression odds (Q3: OR 0.66, 95% CI 0.55–0.78; Q4: OR 0.64, 95% CI 0.52–0.78). Additionally, a 1-unit increase in log2 VK intake was associated with a 15% decrease in depression odds (OR 0.85, 95% CI 0.81–0.90). Restricted cubic splines revealed a non-linear relationship between log2 VK and depression (p for non-linearity

The shear behavior of large-scale weak intercalation shear zones (WISZs) often governs the stability of foundations, rock slopes, and underground structures. However, due to their wide distribution, undulating morphology, complex fabrics, and varying degrees of contact states, characterizing the shear behavior of natural and complex large-scale WISZs precisely is challenging. This study proposes an analytical method to address this issue, based on geological fieldwork and relevant experimental results. The analytical method utilizes the random field theory and Kriging interpolation technique to simplify the spatial uncertainties of the structural and fabric features for WISZs into the spatial correlation and variability of their mechanical parameters. The Kriging conditional random field of the friction angle of WISZs is embedded in the discrete element software 3DEC, enabling activation analysis of WISZ C2 in the underground caverns of the Baihetan hydropower station. The results indicate that the activation scope of WISZ C2 induced by the excavation of underground caverns is approximately 0.5–1 times the main powerhouse span, showing local activation. Furthermore, the overall safety factor of WISZ C2 follows a normal distribution with an average value of 3.697.

Background: Acute intermittent porphyria (AIP) is a rare metabolic disorder that results from mutations in the gene encoding hydroxymethylbilane synthase (HMBS), an enzyme involved in heme biosynthesis. AIP follows an autosomal dominant inheritance pattern, but most carriers are asymptomatic. The clinical manifestations of AIP include acute attacks of abdominal pain and neuropsychiatric disturbances. The pathogenicity of novel HMBS variants identified in Chinese patients has not been well established.Objective: The article aims to identify the pathogenic mutation in an AIP patient and prove its pathogenicity through in vitro experiments.Methods: A 22-year-old female diagnosed with AIP participated in the study. Variant screening of her HMBS gene was carried out through Sanger sequencing. To ascertain the consequences of the newly discovered variant, we conducted in vitro experimentation targeting HMBS gene expression and enzymatic function. Additionally, protein structure analysis was performed. Cycloheximide treatment and UPF1-specific siRNA knockdown were employed to assess the impact of the mutation on the mechanism of non-sense-mediated mRNA decay (NMD).Results: A novel splice site variant in the HMBS gene (c.648_651+1delCCAGG) was detected in the patient, which caused aberrant mRNA splicing. In vitro experiments demonstrated that this variant significantly decreased the expression of HMBS. Further investigation confirmed that this decrease was due to NMD. Additionally, structural analysis indicated that this variant would destabilize the HMBS protein and impair its catalytic activity. To gain a comprehensive understanding of HMBS mutations in the context of AIP, we conducted a literature search on PubMed using the keywords ‘HMBS’ and ‘Acute intermittent porphyria’ from 2013 to 2023. This search yielded 19 clinical case reports written in English, which collectively described 220 HMBS gene mutations worldwide.Conclusion: The study identified and proved the pathogenicity of a novel splice site HMBS variant for the first time. Our results elucidated the pathological mechanism by which this mutation causes AIP through reducing HMBS expression and activity. These findings provide theoretical guidance for the diagnosis, treatment and genetic counseling of AIP patients.

Objectives This study aimed to explore the mediating role of resilience and resignation coping in the relationship between consultation empathy and depression in patients with COVID-19.Design Cross-sectional study.Setting Participants were recruited from a tertiary hospital in Guangzhou, Guangdong province.Participants A total of 215 patients were recruited for this study.Outcome measures A total of 215 patients completed the Consultation and Relational Empathy Measure, Connor-Davidson Resilience Scale, Medical Coping Modes Questionnaire and Hospital Anxiety and Depression Scale. PROCESS 4.1 model 6 was used to analyse the moderated mediating effects.Results Consultation empathy had a positive correlation with resilience (r=0.34, p

Background: Chemoresistance is a common event after cancer chemotherapy, including gastric cancer (GC). Cisplatin has been reported to induce the DNA damage response (DDR), thus leading to chemoresistance. VE-821, a specific inhibitor of ATR, has been proven to suppress a variety of solid malignancies effectively. Our study aimed to explore the effect of VE-821 on enhancing the chemical sensitivity to cisplatin and clarify the potential molecular mechanisms. Methods: Cell viability and apoptosis of MKN-45 and AGS were measured by CCK8 and flow cytometry assay respectively. Western blotting was used to detect the expression of target proteins. TCGA database was used to analyze the correlation between the ATR expression with the prognosis of GC patients. The viability of GC organoids was detected by Cell Titer Glo (CTG) through luminescence. Results: Cisplatin inhibited the proliferation and induced apoptosis of GC cells with a relatively high IC50 value, and increased the phosphorylation levels of ATR-CHK1 and H2AX. VE-821 achieved the same effects but by downregulating the phosphorylation levels of the ATR-CHK1 pathway. Besides, higher ATR expression in GC tissues was positively correlated with higher pathological stage in GC patients. Interestingly, ATR inhibition reversed cisplatin-induced STAT3 activation and enhanced H2AX levels. Moreover, VE-821 significantly sensitized GC cells to cisplatin, and these two drugs had synergistic effects in GC cell lines, organoids, and in vivo. Conclusion: Our results suggested VE-821 sensitized GC cells to cisplatin via reversing DDR activation. And VE-821 treatment may be a promising therapeutic strategy for GC patients with cisplatin resistance.

BackgroundThe Odor Awareness Scale (OAS) is a questionnaire that assesses individual differences in awareness of odors in the surrounding environment, which has been shown to be associated with affective symptoms in recent researches. To further research, A Chinese version of the OAS needs to be introduced.ObjectiveTo investigate the factor structure and validate the psychometric properties of the OAS.MethodsA total of 978 participants from college were randomly allocated into two groups for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. Additionally, the study entailed item analysis and scrutinized internal consistency reliability, test-retest reliability, and concurrent validity. Test-retest reliability was assessed by having 214 participants complete the OAS twice at a one-week interval. Concurrent validity was measured using the Body Odor Sniffing Questionnaire (BOSQ), the Generalized Anxiety Disorder Scale (GAD-7), and the Toronto Alexithymia Scale (TAS-20).ResultsEFA identified three factors that best fit the data: odor sensitivity, odor impact, and odor attention. CFA validated a second-order factor model, yielding good fit indices: χ2/ Df = 2.326, RMSEA = 0.052, CFI = 0.911, TLI = 0.900, SRMR = 0.053. The final version of the OAS comprised 27 items and exhibited a commendable internal consistency reliability (Cronbach’s α = 0.913), and a good test-retest reliability, as evidenced by the high Pearson correlation coefficient (r = 0.940) and intraclass correlation coefficient (ICC = 0.940). The OAS was significantly correlated with BOSQ (r = 0.416), GAD-7 (r = 0.155), and TAS-20 (r = −0.081).ConclusionThe Chinese version of the OAS demonstrated robust reliability and validity, rendering it a valuable instrument for evaluating odor awareness in the Chinese population.

During the excavation of a water-conveyance tunnel in Tertiary soft rocks in China, significant deformation of the surrounding rocks and damage to the support were observed. Substantial horizontal deformation, reaching magnitudes of meters, was observed in the right side wall after a certain period of tunnel excavation. Extensive investigations, including field surveys, monitoring data analysis, laboratory tests, and numerical simulations, were conducted to understand the underlying mechanisms of this large deformation. The section of the tunnel with large deformation consisted of Tertiary sandy mudstone, mudstone interbedded with marl, and glutenite. Laboratory tests and mineral composition analysis revealed that the sandy mudstone and mudstone interbedded with marl exhibited low strength, which was closely related to the water content of the rock specimens. The compressive strength gradually decreased with increasing water content, and when the water content of mudstone interbedded with marl reached 26.96%, the uniaxial compressive strength decreased to only 0.24 MPa. Additionally, sandy mudstone and mudstone interbedded with marl contained a significant amount of hydrophilic minerals, with montmorillonite constituting 30% and 34% of the two rock samples, respectively. The tunnel passed beneath a perennially flowing gully, and a highly permeable glutenite layer was present in the middle of the tunnel. This resulted in groundwater seepage from the inverted arch during excavation, leading to the softening effect on the mudstone interbedded with marl in the lower part of the tunnel. Through numerical simulation and back-analysis techniques, the varying degrees of softening induced by groundwater were quantitatively analyzed in the surrounding rocks on the left and right sides. The study revealed that the large deformation of the tunnel was triggered by two factors: the plastic flow caused by tunnel excavation under the low strength of the surrounding rocks and the softening effect of groundwater. The damage to the support system was primarily attributed to the squeezing and swelling deformation of the surrounding rocks and the non-uniform deformation between different rock layers.

The shear band is an important portion of a landslide. Investigating the shear band’s physical characteristics is one of the most significant challenges for landslide stability analysis and control. A systematic study of shear band in Jinpingzi landslide region II was conducted in this paper. The microscopic composition, deformation, strength, and creep characteristics are investigated by various experiments. In addition, CT visualization technology is utilized to monitor and scan the failure process of the shear band in real-time, as well as carry out studies on failure mechanisms. Furthermore, a constitutive model of the shear band is established as an alternative to the conventional Duncan and Chang model, which does not have this model’s limitations. The associated research will broaden understanding of such a medium’s properties, but it will also be highly useful for stability analysis, deformation prediction, and prevention of such soil-rock mixture landslides.

High slope stability control is a crucial technical issue in water conservancy and hydropower project construction. This issue is relevant throughout the entire engineering-related survey, design, construction, and operation process. This paper reports a recent case in which significant deep-seated deformation occurred during slope excavation. Several unfavorable structural surfaces were revealed throughout the slope’s undercutting process, particularly fault fz39, which ran diagonally through the entire slope from top to bottom. On the slope surface, damage such as cracking, bulging, and local slippage appeared. The measured value of multipoint displacement meters increased in a stepwise pattern with each blast, and the maximum measured value exceeded 100 mm. The studied slope’s whole excavation and reinforcement process is described in detail. We analyzed the deformation mechanism of the excavation slope by combining the geological conditions, real-time safety monitoring findings, and site deformation characteristics. The slope reinforcement scheme was optimized based on the preceding analyses. We used a three-dimensional numerical calculation program to simulate the slope excavation and unloading process to reproduce the current mechanical state of the slope, evaluate the reinforcement measures, and provide a useful reference for decision making. The analysis shows that the deformation behavior of the studied slope is closely related to fault fz39 and fracture L920, and presents a typical wedge failure mode. The deep-seated deformation of the excavation slope occurs at the junction of the wedge and bedrock, which is mainly affected by unfavorable geological structure surfaces, excavation unloading, and blasting vibration. The reinforcement scheme of unloading at the top of the slope and large-tonnage cables are established. The numerical analysis results showed that the design of the slope reinforcement measures was appropriate and ensured slope stability. The work described in this paper deepens our understanding of the occurrence of large deep-seated deformation on the structural-controlled slope under the action of excavation and improves the design philosophy.

This paper addresses the time synchronization problem of asynchronous wireless sensor networks (WSNs) under false data injection attacks. First, we extend the fundamental metric of r-robustness with the notion of trusted links and then show that the structural robustness of networks can be significantly improved without adding additional links after setting a small subset of links to be trusted. Then, for a more practical case where the intercommunication topologies between each sensor node are time-varying, we develop a resilient consensus-based distributed algorithm where the sampling period is allowed to be chosen by each sensor independently and it is shown that the time synchronization problem for WSNs can be solved via the proposed controller. Numerical simulations are conducted to illustrate the effectiveness of our proposed method.

To recommend the excavation procedures and design parameters for underground powerhouses, excavation procedures of fifty-one underground powerhouses in China were summarized and analyzed based on in situ stress conditions. Firstly, the complex stress environment in China was introduced and fifty-one underground powerhouses with their engineering scale, size, lithology, rock classification and in situ stress level were listed in detail. Subsequently, to evaluate the influence of in situ stress levels on excavation procedure design, the correlation between excavation procedures and in situ stress level in three main excavation zones were analyzed accordingly. Moreover, to provide the excavation design recommendations, the strength–stress ratio (SSR) was promoted to analyze and recommend the design parameters, and the blasting excavation design based on the stress transient unloading control was also supplemented. The results show that excavation procedures have different priorities under different in situ stress levels, and the design parameters show an obvious relationship with in situ stress levels. Moreover, the excavation procedure parameters are suggested to adjust accordingly under different SSR. The discussion of influencing factors and specification ensures its rationality and accuracy. It is believed that the summary and recommendations can provide a good reference for excavation procedure optimization of underground powerhouse under high in situ stress.

Based on the analyses of data obtained from the underground powerhouse at Jinping I hydropower station, a comprehensive review of engineering rock mechanics practice in the underground powerhouse is first conducted. The distribution of strata, lithology, and initial geo-stress, the excavation process and corresponding rock mass support measures, the deformation and failure characteristics of the surrounding rock mass, the stress characteristics of anchorage structures in the cavern complex, and numerical simulations of surrounding rock mass stability and anchor support performance are presented. The results indicate that the underground powerhouse of Jinping I hydropower station is characterized by high to extremely high geo-stresses during rock excavation. Excessive surrounding rock mass deformation and high stress of anchorage structures, surrounding rock mass unloading damage, and local cracking failure of surrounding rock masses, etc., are mainly caused by rock mass excavation. Deformations of surrounding rock masses and stresses in anchorage structures here are larger than those found elsewhere: 20% of extensometers in the main powerhouse record more than 50 mm with the maximum at around 250 mm observed in the downstream sidewall of the transformer hall. There are about 25% of the anchor bolts having recorded stresses of more than 200 MPa. Jinping I hydropower plant is the first to have an underground powerhouse construction conducted in host rocks under extremely high geo-stress conditions, with the ratio of rock mass strength to geo-stress of less than 2.0. The results can provide a reference to underground powerhouse construction in similar geological conditions.

The objective of the present study is to analyze the effects of waves on the propulsive performance and flow field evolution of flexible flapping foil, and then offer a way to take advantage of wave energy. The effects of regular waves on the propulsive performance of a two-dimensional flexible flapping foil, which imitated the motion and deformation process of a fish caudal fin, were numerically studied. Based on computational fluid dynamic theory, the commercial software Fluent was used to solve the Reynolds-averaged Navier–Stokes equations in the computational domain. Several numerical models were employed in the simulations, which included user-defined function (UDF), numerical wave tank (NWT), dynamic mesh, volume of fluid (VOF), post-processing, and analysis of the wake field. The numerical tank was also deep enough, such that the tank bottom had no influence on the surface wave profile. First, the numerical method was validated by comparing it with experimental results of rigid foil, flapping under waves. The effects of three key wave parameters on the propulsive performance of flexible and rigid foils were then investigated; the results show that higher performance can only be obtained when the motion frequency of the foil was equal to its encounter frequency with the wave. With this precondition, foils were able to generate higher thrust force at larger wave amplitudes or smaller wavelengths. Similarly, the percentage of wave energy recovery by foils was higher at smaller wave amplitudes or wavelengths. From a perspective of wake field evolution, increasing foil velocity (relative to water particles of surrounding waves), could improve its propulsive performance. In addition, flexible deformation of foil was beneficial in not only enhancing vortex intensity but also reducing the dissipation of vortices’ energy in the flow field. Therefore, flexible foils were able obtain a better propulsive performance and higher wave energy recovery ability.

Rock-soil aggregate, as a specific geomaterial, exhibits complicated mechanical behavior. The rock-soil aggregate sampled from the deep layer of sliding mass at Jinpingzi area of Wudongde hydropower plant on Yangtze River is investigated to understand its mechanical behavior. Large-scale laboratory triaxial tests are conducted considering different gradations, stone contents and confining pressures. The results show that variation of stone content and gradation considerably affects the mechanical characteristics of rock-soil aggregate. Further, the influences of stone content, and gradation variation on stress-strain curve, Mohr-Coulomb criterion based shear strength parameters, Duncan-Chang model based deformation parameters, and internal friction angle are analyzed. A modified Rowe’s stress-dilatancy equation describing the mechanical response of rock-soil aggregate is then suggested.