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Focusing on the S1212 working face in Ningtiaota coal mine, this study investigates a soft mold filling wall as a primary support strategy for gob-side entry retention. The research aims to overcome the challenges of poor rock stability and complex support requirements under hard roof and large mining height conditions. A structural mechanical model of the surrounding rock was developed, from which a quantitative relationship between the support resistance of the soft mold filling wall and mining height was analytically derived. Numerical simulations were conducted to systematically investigate the effects of varying mining heights and wall widths on wall vertical stress, solid coal rib stress, and roadway deformation, thereby elucidating the load-bearing behavior of the wall and identifying optimal wall widths for different mining heights. The results demonstrate that: (1) At a constant mining height, vertical stress within the wall decreases progressively with increasing wall width, whereas at a constant wall width, increasing the mining height markedly amplifies vertical stress. (2) With increasing wall width, the solid coal rib peak stress decreases and its maximum shifts deeper into the rock mass, in contrast, under larger mining heights, the peak stress intensifies and migrates toward shallower zones. (3) Across varying mining heights, roadway floor heave exhibits an overall reduction with increasing wall width, however, the mitigation effect plateaus once the wall width surpasses a critical threshold. Integrating theoretical derivation with numerical analysis, the optimal wall width for the S1212 working face was determined as 1.4 m. Field validation further demonstrated that when the working face advanced 80 m, deformation of the surrounding rock stabilized, with a convergence deformation of 48.8 mm, thereby ensuring effective roadway stability control.

Under deep, high-intensity mining conditions, a high mineral pressure develops at the working face, which can easily cause floor heave deformation of the roadway. In this paper, with the geological conditions of Buertai coal mine as the background, through on-site monitoring and numerical simulation, the mechanism of strong dynamic pressure roadway floor heave is clarified and a cooperative control method for roadway floor heave deformation is proposed. The main conclusions are as follows: (1) The overall strength of the floor of this strong dynamic pressure roadway is low, which can easily cause roadway floor heave, and on-site multivariate monitoring of the mine pressure is carried out, which clarifies the evolution law of the mine pressure of the mining roadway and along-the-airway roadway. (2) Combined with FLAC3D numerical simulation software, we analyze the influence of coal seam depth and floor lithology on the stability of the roadway floor and find that both have a significant influence on the stability of the roadway. Under the condition of high-intensity mining, the floor will deteriorate gradually, forming a wide range of floor heave areas. (3) Based on the deformation and damage mechanism of the roadway floor, a synergistic control method of “roof cutting and pressure relief + floor anchor injection” is proposed and various technical parameters are designed. An optimized design scheme is designed for the control of floor heave in Buertai coal mine.

The bearing capacity and yieldable performance of yielding U-shaped steel support are difficult to be fully exerted in roadways under complex conditions, and serious deformation and damage occur frequently. Taking the mining roadways of Tangkou Coal Mine in a kilometer-deep well as the engineering background, this paper summarizes and analyzes the typical failure modes of the on-site yielding U-shaped steel support. By utilizing the independently developed full-scale arch frame test system, the bearing performance tests of arch frames with different sectional methods were carried out. The results show that compared with the three-section U-shaped steel support, the yieldable performance of the four-section support is increased by 21.8%, while the bearing capacity is only decreased by 1.9%. Furthermore, numerical tests on yielding U-shaped steel support under different load patterns and different cross-sectional forms were conducted to clarify the deformation characteristics and internal force distribution laws of U-shaped steel support under complex stress conditions. Finally, a sectional design method for yielding U-shaped steel support and on-site engineering suggestions were put forward. Based on this methodology, it is feasible to optimize the support structure scheme that better matches the engineering geological conditions, thereby fully utilizing the yielding characteristics and load-bearing capacity of the support. This approach effectively prevents premature local failure of the support, extends its service life, and enhances the safety of roadway support engineering while achieving significant economic benefits.

Diabetic cardiomyopathy (DCM) is a kind of myocardial disease that occurs in diabetes patients and cannot be explained by hypertensive heart disease, coronary atherosclerotic heart disease and other heart diseases. Its pathogenesis may be closely related to programmed cell death, oxidative stress, intestinal microbes and micro-RNAs. The excessive activation of mineralocorticoid receptors (MR) in DCM can cause damage to the heart and kidneys. The third-generation non-steroidal mineralocorticoid receptor antagonist (MRA), finerenone, can effectively block MR, thus playing a role in protecting the heart and kidneys. This review mainly introduces the classification of MRA, and the mechanism of action, applications and limitations of finerenone in DCM, in order to provide reference for the study of treatment plans for DCM patients.

INTRODUCTION:Serum insulin-like growth factor 1 (IGF-1), a hepatocyte-derived cytokine, has been suggested to reflect hepatic function reserve. The aim of this systematic review and meta-analysis was to investigate the association between serum IGF-1 levels on the admission and prognosis of patients with advanced liver diseases.METHODS:A thorough examination of the literature was conducted across various databases, namely PubMed, Embase, Web of Science, Wanfang, and CNKI, with the aim of identifying relevant cohort studies. The data were synthesized using the random-effects model, taking into account the potential impact of heterogeneity.RESULTS:A total of 9 cohorts were included. Patients with a low serum level of IGF-1, as compared with those with a high IGF-1 at baseline, exhibited a significantly poorer transplant-free survival (risk ratio: 3.03, 95% confidence interval: 2.17 to 4.22, P < 0.001), with no significant heterogeneity observed (P for Cochrane Q test = 0.92, I2 = 0%). A sensitivity analysis, which was conducted by excluding 1 study at a time, yielded consistent results (risk ratio: 2.94-3.24, P all < 0.05). In addition, consistent results were observed in further subgroup analyses based on various factors, including cutoffs of IGF-1, country of the study, patient diagnosis, methods for measuring serum IGF-1, follow-up duration, analytic model, and quality scores (P for subgroup difference all > 0.05).DISCUSSION:A diminished serum IGF-1 level on admission could potentially serve as an indicator for an unfavorable prognosis among patients afflicted with advanced liver disease, such as severe hepatitis and cirrhosis.

Affected by high in-situ stress and mining activities, In the original support scheme, entry of guotun coal mine is seriously deformed. The side of the head entry bulges out seriously and the roof sinks seriously. In order to solve the problem of large deformation of roadway, guotun coal mine adopts the technology of a nonpillar mining method with entry automatically retained in 4306 mining face. First, taking method of theoretical analysis, the stress model of blasthole under the deep condition is established, the mechanical conditions of crack propagation under the action of directional detonation wave and high surrounding rock binding force are obtained theoretically. Next, the mechanical model of roof cutting and pressure relief is established. Afterwards, The mechanical model of directional blasting under the condition of stress constraint is established by using LS-DYNA numerical calculation software, the evolution characteristics of effective stress and the law of crack growth are analyzed. In the end, the field test was carried out in 4306 mining face, and the blasting effect was observed by drilling peep, and the deformation of the head entry before and after pressure relief was monitored and analyzed. The results show that directional fracture blasting can produce a continuous crack, and the effect of pressure relief is remarkable, effectively controlling the deformation of surrounding rock under high in-situ stress.

To explore the influence of abandoned roadways on the technology of gob side entry retaining formed by roof cutting and pressure release, theoretical analyses, numerical simulations, and field engineering experiments are adopted to study the mining pressure distribution law, plastic zone evolution characteristics and surrounding rock control measures when the working face crosses an abandoned roadway. Mining to the vicinity of the abandoned roadway is equivalent to the process of recovering coal pillars. During the mining process, the width of the coal pillar decreases. Under the influence of mining pressure, the coal pillar will gradually lose its bearing capacity. The overburden rock gravity originally borne by the coal pillar will transfer to the retaining roadway and the coal seam in front of the abandoned roadway. Therefore, it is necessary to strengthen the support of the retaining roadway to prevent large deformations due to the sudden increase in pressure. Within 20 m near the abandoned roadway, based on the original NPR constant resistance large deformation cable (CRLD cable) support scheme, the second row of the CRLD cables is densely arranged, and the cable spacing is encrypted from 2400 to 800 mm. The successful application of these research results in actual engineering applications can provide a useful reference for working faces under similar geological condition.

With the development of coal resource mining at depth, rock burst and other disasters faced by deep mining are more and more common. However, deep mining still needs to face the complex geological environment of high stress. This study first analyses the structural characteristics and mechanical model of gob-side entry retaining and puts forward the corresponding control technology. Based on that, the technology of gob-side entry retaining by directional roof cutting is introduced, including pressure relief technology by directional roof cutting and constant resistant and large deformation anchor cable support technology. At the same time, reasonable charging structure parameters are determined by borehole observation equipment, and support parameters are designed considering the roof lithology and impact-resistance ability. Through the field engineering practice, surrounding rock of gob-side entry retaining is effectively controlled by analysing the monitoring equipment, which lays a theoretical and practical foundation for the large-scale application of the technology of gob-side entry retaining by directional roof cutting in deep coal mines.

In recent years, with the extension of the coal mine at depth, rock bursts are more and more frequent. Therefore, the research of roadway support and pressure relief has become the key to prevent rock burst. In this paper, the primary high strength support and hydraulic fracturing pressure relief measures of roadway are studied and analysed. The primary high strength support emphasizes the matching characteristics of support materials, strengthen the protection of the active support to the roadway, and realize an integrated support system. Considering strong burst-prone area, the hydraulic fracturing is used to achieve pressure relief of surrounding rock mass, which can release and transfer the energy within the range of pressure relief. When there is energy release outside the range of protection system, the pressure relief region can absorb the energy so as to achieve the purpose of protecting the roadway. A field engineering case is applicated, the results shown that the stress of roadway surrounding rock and micro seismic energy significantly decreases, reducing the possibility of rock bursts.

Mineralocorticoid receptor antagonists (MRAs) are pivotal in heart failure (HF) management. This study evaluates their impact on adverse cardiovascular events and left ventricular ejection fraction (LVEF) in HF patients. A comprehensive literature search was conducted across PubMed, Embase, Cochrane Library, Web of Science, and ClinicalTrials databases, with a cutoff date of September 30, 2024. All included studies were randomized controlled trials (RCTs) that recorded the incidence of adverse cardiovascular events and changes in LVEF after MRA treatment in HF patients. A total of 30 randomized controlled trials involving 24,831 patients with heart failure were included. Compared to conventional therapy or placebo, treatment with MRAs significantly reduced the risk of all-cause mortality (RR = 0.862, 95% CI: 0.778-0.956,  = 0.005;  = 36.1%), cardiovascular mortality (RR = 0.828, 95% CI: 0.732-0.937,  = 0.003;  = 45.7%), and heart failure-related hospitalization (RR = 0.780, 95% CI: 0.657-0.926,  = 0.005;  = 65.5%). Moreover, MRAs significantly improved LVEF (WMD = 1.384, 95% CI: 0.208-2.559,  = 0.021;  = 59.9%). However, MRA therapy was associated with an increased risk of renal dysfunction, including hyperkalemia (RR = 2.086, 95% CI: 1.872-2.325,  < 0.001;  = 0.0%), elevated serum creatinine (RR = 1.512, 95% CI: 1.252-1.825,  < 0.001;  = 0.0%), decreased eGFR (WMD = -5.223, 95% CI: -7.380 to -3.066,  < 0.001;  = 0.0%), and potentially increased incidence of composite renal outcomes. MRAs significantly reduce the risk of adverse cardiovascular events in patients with heart failure and contribute to LVEF improvement. They lower all-cause mortality in patients with HFrEF and reduce hospitalization for heart failure in those with HFmrEF or HFpEF. However, the potential risk of renal-related adverse events warrants close monitoring. Our protocol was registered in PROSPERO (registration number: CRD42024592012).