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The objective is to study the design method of roadway support and provide technical support for coal mining and other mining methods that need deep roadway excavation. Through literature review, the occurrence, development mechanism and influencing factors of surrounding loose rock zones of roadways are analyzed. A method of detecting is selected according to the characteristics of surrounding rock loosening. Knowledge of elastoplastic mechanics is used to theoretically study the failure mechanism of surrounding rock in deep re-mining roadways. Based on the artificial neural network prediction model (ANN), the surrounding rock is classified and a support network model of the decision system is constructed. After the design of roadway support, a sharp change of vault subsidence normally occurs within about 7 days after excavation, and the total subsidence is 14 mm. In the following month, deformation is slow, subsidence is small, and it is basically stable after one month. The curve of the vault subsidence rate shows that the vault subsidence rate is less than or equal to 1mm/d after 7 days. The convergence rate is also less than 1 mm/d after 7 days. There are two cave mouths AB and CD, and the convergence value of AB is 6.47mm, CD is 10.26mm: CD is slightly larger than AB, and it is close to stable one month later. It is essentially consistent with the time of vault settlement and stability, and the amount of deformation is approximately the same. This shows that, with the advance of the working face, the displacement of the surrounding rock in the section away from the working face will gradually decrease and the surrounding rock will be stable. The stability time of surrounding rock displacement of the portal section is the same as that of vault subsidence under the initial support, and the amount of deformation is approximately the same, indicating that the support parameters and construction methods are reasonable.

Mining-induced fractures resulting from shallow coal seam extraction in the loess gully region of China are complex and variable, presenting critical hazards including water and sand inrush, as well as air leakage, all of which severely endanger operational safety. This study aims to examine the spatiotemporal evolution characteristics of mining-induced fractures in shallow coal seams within China’s loess gully region. Focusing on the Shenfu mining area, a combination of theoretical analysis, numerical modeling, and physical similarity simulation is employed to investigate mining processes and fracture development in shallow coal seams within loess gully. Findings indicate that the loess gully surface contains highly concentrated stress regions, distributed both horizontally and vertically. Mining-induced fractures along the slope primarily experience tensile failure, and most are ultimately closed due to the rotary extrusion exerted by the slope; The evolution of mining-induced fractures exhibits three distinct periodic development patterns: “half cycle” (inoculation—expansion—stationary), “single cycle” (inoculation—expansion—semi-closed or closed), and “double cycle” (inoculation—initial expansion—initial closure—secondary expansion—secondary closure) within the loess gully region. Through the development of a “rock chain structure” model for overlying strata, the dynamic mechanisms driving the three periodic mining-induced fracture types are individually elucidated. Analyzing the stress state of the “rock chain structure” model under linear loading reveals the instability conditions of the bedrock structure and the fracture types resulting from linear loading. These findings offer both theoretical insights and practical guidance for further research and engineering applications in shallow coal seam mining within loess gully regions.

Land use directly affects the carbon emissions and carbon stock of the ecosystem, and indirectly affects the carbon emissions from anthropogenic activities, which occur more frequently in coastal regions. Taking Nantong City as an example, detailed carbon emission projects were classified and calculated for different land use types by combining land use images of five typical years. Based on the complex relationship between land use carbon emissions and socio-economic factors, the system dynamics model (SD) was used to simulate the land use carbon emissions from 2005 to 2060, and to construct carbon-neutral policy scenarios. Compared with inlands, carbon emissions from land use in Nantong are more pronounced than inland areas, and unique land use types, such as shallows, play an important role as carbon sinks. Total land use carbon emissions show an upward trend from 2005 to 2020 and carbon emissions from construction land dominate. Under the natural development condition, the total net carbon emissions of Nantong are about 4,298,250 tons in 2060, failing to achieve carbon neutrality. The scenario with all four policies adjusted (LO, IO, TP, and PC) has the best emission reductions, peaking at 10,949,010 tons of net carbon emissions in 2029 and reducing them to 1,370,202 tons in 2060, which is the scenario closest to the carbon-neutral target. Overall, this study provides a meaningful conclusion for the study of land use carbon emission characteristics and low-carbon pathways in coastal cities, which can guide the formation of government policies.

Because of the control problems caused by the non-uniform load of the roof of the working face when the shallow coal seam is mined under the condition of gully terrain. In this study, theoretical analysis, similar simulation, and field measurement methods are comprehensively used to incorporate gully topographic factors into the study of roof structure control, and a mechanical model of roof structure under non-uniform load is constructed. The interaction relationship between “powered roof support-rock mass” during the period of periodic pressure is analyzed, the corresponding model is established, and then the calculation equation of support resistance for controlling the sliding instability of the roof structure passing through the gully is derived. Taking the first mining face of Shaliang Coal Mine as the engineering background, reasonable support resistance is given based on the above research results. Through similar simulation experiments, the average weighting steps in the mining stage of downhill, gully bottom, uphill, and convex landforms are 19 m, 30 m, 14 m, and 15 m, respectively. The periodic weighting step in the gully bottom stage is the largest and the uphill mining stage is the shortest. Verified by field measured data, the derived equation is accurate and reliable. The research results enrich the roof control theory of shallow coal seam mining, provide key technical support and practical guidance for coal mining under similar geological conditions, and help to ensure coal mine safety production.

In our previous study, we found significant differences in the mRNA and microRNA (miRNA) levels among hypertensive patients with different degrees of vascular endothelial cells damage. These differences were closely associated with endoplasmic reticulum stress (ERS)-related proteins. Moreover, compared to the control group, the expression of transcription factor activating factor 4 (ATF4) was also found to be significantly different in the hypertensive patients with different degrees of vascular endothelial cells damage groups. These results were confirmed using gene prediction software, which showed synergistic effects between ATF4 and miR-1283. ATF4 is a key molecule in ERS. Three ERS pathways exist:protein kinase RNA-like ER kinase (PERK), activating transcription factor 6 (ATF6) and inositol-requiring enzyme-1 (IRE-1)-induced apoptosis. The PERK pathway is the most important and also includes the phosphorylation of eukaryotic translation initiation factor 2α (eIF2α) and ATF4. In this report, we studied the regulatory effects of miR-1283 and ATF4 on the PERK-eIF2α-ATF4 signaling pathway using human umbilical vein endothelial cells (HUVECs) and mice. We verified the relationship between miR-1283 and ATF4 using a luciferase activity assay and observed the regulatory effects of miR-1283 and ATF4 on the PERK-eIF2α-ATF4 signaling pathway in vivo and in vitro. ATF4 is a target gene of miR-1283, which regulates the PERK-eIF2α-ATF4 signaling pathway by inhibiting ATF4, and it plays a critical role in inducing injury in HUVECs and mouse heart tissue.

Observational studies suggested increased risks of Alzheimer’s disease (AD), Parkinson’s disease (PD), and multiple sclerosis (MS) in patients with Crohn’s disease (CD) and ulcerative colitis (UC). We aimed to assess the causality for the associations of CD and UC with the risks of AD, PD, and MS through a two-sample Mendelian randomization (MR) study. Independent single nucleotide polymorphisms associated with CD (17,897 cases and 33,977 controls) and UC (13,768 cases and 33,977 controls) were identified as genetic instruments based on a European-descent genome-wide association study (GWAS) released by the International Inflammatory Bowel Disease Genetics Consortium. Summary statistics for AD (combined: 25,881 cases and 256,837 controls), PD (combined: 35,836 cases and 665,686 controls), and MS (combined: 48,477 cases and 285,515 controls) were obtained from the largest GWASs and FinnGen study of European ancestry, respectively. MR estimates were generated using the inverse-variance weighted method in the main analysis with a series of sensitivity analyses. MR analyses were conducted per outcome database and were subsequently meta-analyzed to generate combined estimates. Genetically predicted UC was significantly associated with increased risks of AD (combined: OR, 1.03; 95% CI, 1.01–1.05; P  = 1.80 × 10 −3 ) and MS (combined: OR, 1.37; 95% CI, 1.23–1.53; P  = 1.18 × 10 −8 ), while there was no association between genetically predicted UC and the risk of PD. In contrast, no significant associations were observed for genetically predicted CD with AD, PD, and MS. MR-Egger regression showed no directional pleiotropy for the identified associations, and sensitivity analyses with different MR methods further confirmed these findings. This study suggested significant adverse effects of UC on AD and MS, highlighting that UC patients should receive early intervention with optimal adjunctive medical therapy to reduce the risks of AD and MS.

This study evaluates the stress tolerance and metabolic adaptability of twelve yeast strains, including eleven commercial strains from Wyeast Laboratories and one prototrophic laboratory strain, under industrially relevant conditions. Yeast strains were assessed for their fermentation performance and stress responses under glucose limitation, osmotic stress, acid stress, elevated ethanol concentrations, and temperature fluctuations. Results revealed significant variability in glucose consumption, ethanol production, and stress tolerance across strains. ACY34 and ACY84 demonstrated the highest fermentation efficiency, while ACY19 exhibited exceptional stress resilience, excelling under multiple stress conditions such as osmotic and ethanol stress. The findings highlight strain-specific performance, with some strains suited for high-yield fermentation and others excelling under challenging environmental conditions. These results provide critical insights for selecting and optimizing yeast strains tailored to specific industrial fermentation processes, contributing to improved productivity and product quality in food and beverage production.

The increasing use of cable-stayed bridges with steel box girders necessitates more sophisticated design approaches, as the diverse environments of bridge locations place higher demands on the design process. Determining a reasonable finished state is a critical aspect of bridge design, yet the current methods are significantly constrained. A new approach to optimizing the finished state is proposed. This method’s practicality and efficiency are verified through a case study, analyzing how constraints on vertical girder deflection, horizontal pylon displacement, cable forces, and cable force uniformity affect the optimization outcome. The results show that convergence of the mixed-constraint quadratic programming model is achieved within 30 iterations, yielding an optimized finished state that meets the design criteria. The chosen constraint ranges are deemed appropriate, and the optimization method for the construction stage is thus demonstrably feasible and efficient. The multiplier path following optimization algorithm is computationally efficient, exhibiting good convergence and insensitivity to the problem size. Being easy to program, it avoids the arbitrariness of manual cable adjustment, enabling straightforward determination of a reasonable finished state for the cable-stayed bridge with a steel box girder. The vertical displacement of the main girder, the positive and negative bending moments, and the normal stresses at the top and bottom edges, as well as the positive and negative bending moments in the towers, are significantly influenced by the constraint ranges. The horizontal displacement of the pylon roof is significantly affected by the constraint ranges of both the main girder’s vertical displacement and the pylon’s horizontal displacement, while the remaining constraint ranges have a limited impact.

ABSTRACT Background Bacterial coinfection in patients with SARS‐CoV‐2 infection is an important risk factor for death. This study investigated whether there were differences in levels of serum inflammatory markers in COVID‐19 patients with bacterial coinfections compared with those without bacterial infection. Methods A total of 235 inpatients with SARS‐CoV‐2 infection admitted to Qingdao Central Hospital from December 7, 2022, to August 7, 2024, were included. Patients were divided into a bacteria‐positive group (115 cases) and a bacteria‐negative group (120 cases) according to whether they had bacterial coinfections. PCT, CRP, and 12 kinds of cytokines were compared between groups, and the distribution of bacterial species in the positive group was statistically analyzed. Results The serum levels of CRP (Z = 8.94, p < 0.001), PCT (Z = 5.59, p < 0.001), IL‐1β (t = 4.863, p < 0.001), IL‐2 (t = 5.810, p < 0.001), IL‐5 (t = 3.837, p < 0.001), IL‐6 (t = 4.910, p < 0.001), IL‐8 (t = 3.325, p < 0.001), ILIL‐12p70 (t = 4.722, p < 0.001), IL‐17 (t = 3.315, p = 0.001) and TNF‐α (t = 4.251, p < 0.001) between the two groups were significantly different. IL‐4, IL‐10, IFN‐α, and IFN‐γ were not statistically significant (p > 0.05). Among the 115 bacteria‐positive patients, 56 patients were positive for one species and 59 patients were multiple infections. Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae were common species. Conclusions Serum PCT and CRP levels in COVID‐19 patients with bacterial coinfection are higher than those without bacterial infection. Cytokines such as IL‐1β, IL‐2, IL‐5, IL‐6, IL‐8, IL‐12p70, IL‐17, and TNF‐α may be involved in the progression of COVID‐19 combined with bacterial infection. They can be used as potential markers to evaluate the disease condition and prognosis. Serum cytokines including IL‐1β, IL‐2, IL‐5, IL‐6, IL‐8, IL‐12 p70, IL‐17, and TNF‐α were significantly higher in COVID‐19 patients with bacterial coinfections than those without bacterial infection. These cytokines may be involved in the progression of COVID‐19 combined with bacterial coinfections.