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Highlights Developing a universal strategy of the p–n homojunction engineering that could significantly boost electron mobility of electron transport layer (ETL) by two orders of magnitude. Proposing a new mechanism based on p–n homojunction to explain inhibited carrier loss at buried interface. Setting a new performance benchmark as high as 25.50% for planar perovskite solar cells employing TiO2 as ETLs.

Abstract Recent methods of learning latent representations in Domain Adaptation (DA) often entangle the learning of features and exploration of latent space into a unified process. However, these methods can cause a false alignment problem and do not generalise well to the alignment of distributions with large discrepancy. In this study, the authors propose to explore a robust subspace for Semi‐Supervised Domain Adaptation (SSDA) explicitly. To be concrete, for disentangling the intricate relationship between feature learning and subspace exploration, the authors iterate and optimise them in two steps: in the first step, the authors aim to learn well‐clustered latent representations by aggregating the target feature around the estimated class‐wise prototypes; in the second step, the authors adaptively explore a subspace of an autoencoder for robust SSDA. Specially, a novel denoising strategy via class‐agnostic disturbance to improve the discriminative ability of subspace is adopted. Extensive experiments on publicly available datasets verify the promising and competitive performance of our approach against state‐of‐the‐art methods.

Abstract Epidermal growth factor receptor (EGFR)-targeted drugs (erlotinib, etc.) are used to treat multiple types of tumours. EGFR is highly expressed in most triple-negative breast cancer (TNBC) patients. However, only a small proportion of TNBC patients benefit from EGFR-targeted drugs in clinical trials, and the resistance mechanism is unclear. Here, we found that PDZ domain containing 1 (PDZK1) is downregulated in erlotinib-resistant TNBC cells, suggesting that PDZK1 downregulation is related to erlotinib resistance in TNBC. PDZK1 binds to EGFR. Through this interaction, PDZK1 promotes EGFR degradation by enhancing the binding of EGFR to c-Cbl and inhibits EGFR phosphorylation by hindering EGFR dimerisation. We also found that PDZK1 is specifically downregulated in TNBC tissues and correlated with a poor prognosis in TNBC patients. In vitro and in vivo functional assays showed that PDZK1 suppressed TNBC development. Restoration of EGFR expression or kinase inhibitor treatment reversed the degree of cell malignancy induced by PDZK1 overexpression or knockdown, respectively. PDZK1 overexpression sensitised TNBC cells to erlotinib both in vitro and in vivo. In conclusion, PDZK1 is a significant prognostic factor for TNBC and a potential molecular therapeutic target for reversing erlotinib resistance in TNBC cells.

Under the background of “dual-carbon” goal and current technological conditions, coal, waste and carbon constitute an impossible triangle in the coal industry which severely constrains its green, low-carbon, and sustainable development. Adhering to the principles of treating waste with waste and returning the waste to where it comes from, with a focus on the three-dimensional perspectives of damage reduction in coal mining, the functional utilization of mining waste, and low-carbon disposal of carbon in mining industry, this paper explores a synergistic development path for coal, waste and carbon. It provides a comprehensive solution to unravel the impossible triangle and promote the overall green, low-carbon development of coal industry. The specific contributions of this work include: ① Clarifying the scientific connotation of damage reduction in coal mining, the spatial combination characteristics of aquifers in the ecologically fragile areas, the movement patterns of overlying strata under the application of coal mining damage reduction techniques, and the surface deformation patterns resulting from overlying strata damage; proposing the original technologies of drilling-backfilling-retention for section pillar extraction, narrow strip mining with backfill, and backfilling behind fully-mechanized longwall face aiming to address the challenges posed by damage reduction mining; ② Interpreting the scientific connotation of functional utilization for mining waste; clarifying the scientific issues related to the modification methods and mechanisms of magnesium-coal-based solid waste material, the mechanisms of synergistic interactions among diverse solid wastes, and the properties control of total solid waste backfilling materials. These efforts have led to the establishment of a key technological system for the functional utilization of solid waste, with a core focus on the modification of solid waste raw materials, the development of solid waste-based cementitious materials, and the preparation of solid waste based backfilling materials; ③ Elucidating the scientific connotation of low-carbon disposal of carbon with a scientific practical framework and implementation pathway; clarifying some scientific issues related to mineralization material preparation, storage space construction, CO2 storage and control mechanisms, the long-term environmental effects of CO2 storage, and reservoir stability in the low-carbon disposal process of carbon. The scientific issues related to mineralization material preparation, seal space key technologies such as fractured space CO2 storage and CO2 sequestration through coal mine carbon solidification are explicitly defined which results in a new model for achieving a low-carbon CO2 storage in coal mine goaf. Based on the green, low-carbon and sustainable development of coal industry, it is of great significance to collaboratively promote the damage reduction in coal mining, the functional utilization of mining waste, and the low-carbon disposal of carbon. This coordinated effort plays a crucial role in advancing the realization of the dual-carbon goal in the coal industry.

To expedite the achievement of the ''30–60 double carbon'' goal, it is imperative to create a novel, low-carbon, cost-effective, and sustainable backfill material for mining purposes. Against this background, this paper investigates the workability, carbonation performance and carbon sequestration capacity of coal gangue (CG), magnesium slag (MS) and fly ash (FA) as magnesium coal slag solid waste backfill material. The results of the study show that: (1) The rheological properties of the CFM fresh slurry conform to the Herschel-Balkley (H-B) model, and its flowability meets the requirements of mine backfill transport. With increasing MS content, the yield stress, apparent viscosity, thixotropy and shear thickening of CFM fresh slurry increase, and the micro-slump and diffusion diameter decrease. (2) Carbonation curing can effectively improve the early UCS of CFM. The highest UCS of CFM was 8.854 MPa after 7 days of carbonation curing, which was 27.84 times higher than that of standard curing. In addition, the UCS of CFM increased with the increase of curing age and MS content. (3) CFM produces a large number of carbonation products such as calcium carbonate after carbonation curing, which makes its microstructure denser. (4) CFM can absorb up to 14.55 % of CO2 after carbonation. (5) The volume stability of CFM is significantly improved after carbonation curing. In summary, CFM is not only a new type of low-cost, low-carbon and sustainable solid waste backfill material, but its practical application in the field of mine backfilling also has great potential for the realization of magnesium coal slag solid waste resource utilization and CO2 sequestration.

Under the national “dual carbon” goal, how to reduce the carbon emissions of the coal industry and achieve carbon storage has become an urgent problem to be solved. The coal industry is the producer of high carbon fossil energy and the main carbon emission source provider. In the process of production and consumption, the accumulation of bulk solid waste, the formation of large goaf and a large amount of CO2 emissions are the bottlenecks that restrict the sustainable development and utilization and the green and healthy development of the coal industry. In order to solve the problem of carbon dioxide storage and mine waste consumption, the bulk solid waste disposal, high-value solid waste utilization, CO2 storage and goaf utilization were organically combined, the concept of carbon dioxide backfill was put forward, and three types of dioxide backfill were defined from the perspective of carbon sink capacity assessment. ① The basic theories involved in the transportation process of CO2 filling slurry and mineralization reaction process are analyzed. The mathematical equations for each process and calculation formulas for carbon sequestration amount are provided. The influence of factors such as temperature and humidity on the mineralization reaction mechanism, carbon sequestration amount, and strength of the backfill body are pointed out. ② The carbonation technological approaches, CO2 sequestration capacity of major alkaline industrial solid wastes and enhancing measures of CO2 mineralization are summarized. On this premise, two types of CO2 backfill materials preparation technique based on direct carbonationand or indirect carbonationand are presented, which can fulfill the criterion of mine backfill in fluidity, solidification characteristics and strength. ③ To solve the problem of decomposed CO2 escaping during CO2 backfill, two technical paths of strip roadway paste backfilling and intermittent backfilling behind packed hydraulic support have been proposed. The former sequesters decomposed CO2 by constructing backfilling bodies with multiple through holes in the weak backfilling strip, while the latter uses packed hydraulic support and chain self-filling baffling to construct backfilling strips in longwall goaf to control roof caving and form a CO2 physicochemical storage space. ④ In order to evaluate the carbon balance effect of CO2 backfill, the calculation boundary of carbon footprint and carbon sequestration in CO2 backfill was defined according to the life cycle method, including the stages of raw material mining, transportation, processing, injection, solidification, etc. Then, the carbon footprint and carbon sequestration in the CO2 backfill process were sorted out, and factors such as the source, dosage, loss, and conversion of CO2 were considered. Next, the calculation methods of carbon footprint and carbon sequestration in the processes of raw material transportation, filling slurry preparation, underground injection and filling were given. The research results are expected to reduce the energy consumption and cost of CO2 storage, and have far-reaching significance for green coal mining and sustainable development and utilization.

Abstract Wet carbonisation of alkaline industrial solid waste is considered to be an effective method for CO2 capture/processing of solid waste resources. Aiming at the high-value utilisation of modified magnesium slag in Shaanxi Province, a new method for producing carbon absorption backfill materials (CABM) is proposed by introducing CO2 into freshly mixed modified magnesium slag slurry. Through rheological, mini-slump, isothermal microcalorimeter test, uniaxial compressive strength, X-ray diffraction (XRD), thermogravimetry (TG-DTG) and scanning electron microscopy (SEM) experiments, the effects of CO2 on the fluidity, hydration, mechanical and microstructural properties of freshly modified magnesium slag slurry are investigated. The results show that: (1) while the introduction of CO2 significantly reduces the fluidity of a CABM, it can still meet the requirements of pipeline transportation in backfill mines; (2) the tiny calcium carbonate grains produced during the carbonation reaction can provide additional nucleation sites for the growth and diffusion of hydration products in CABM, and accelerate the hydration heat release rate; (3) the introduction of CO2 into the freshly mixed modified magnesium slag slurry not only helps to improve the compressive strength of the CABM samples at 28 days, but also has a good carbon absorption effect (5.2–7.6%); (4) through XRD, TG-DTG and SEM experiments, it is concluded that the carbonation reaction in the slurry does not prevent the further hydration of the modified magnesium slag, but is helpful for promoting a rapid hydration reaction in a later stage. Therefore, to maintain good fluidity and carbon absorption of the CABM, the backfill slurry should have a water/modified magnesium slag mass ratio of 0.5, a ventilation rate to of 1 L/min, and a ventilation stirring time of 5 min.

The addition of a temperature-rising inhibitor (TRI) to aeolian sand paste materials (ASPM) to produce paste-like filling mining materials can solve multiple problems. First, it may alleviate the environmental problems caused by solid waste treatment in mines to achieve sustainable use of solid waste. Second, It may solve the problem of rapid temperature rise in mines caused by the rapid heat release during filling body hydration. Therefore, this study explored the hydration of an ASPM with different TRI contents and its mechanical properties, setting time, and microstructure. The results show that at TRI contents of 0–1.0%, the peak heat-release rate of the ASPM is reduced by 16.0%, the early hydration heat release is reduced by 14.2%, and the delay of the heat-release peak is more prominent. TRI inhibits the hydration of ASPM primarily within 7 d, which reduces the early strength of the ASPM by a maximum of 43.4%. However, with the increase in age, the strength difference gradually decreases, and TRI even becomes beneficial for the development of strength in later stages. In addition, the high content of TRI has a significant retarding effect on ASPM hydration. The temperature rise test shows that TRI can reduce the temperature increase rate and delay the peak temperature increase rate, which can effectively solve the problem of concentrated heat release by backfill. This paper provides a theoretical basis for the application of TRIs in cemented paste backfill.

Pumpkin polysaccharides (PPe) have a variety of bioactive effects and our previous research showed the acid hydrolysate (PPe-S, a mixture) from PPe had an antioxidative capacity both in vitro and in viro. The aim of this study was to purify PPe-S and investigate the antioxidant stress effects of 2 purified components (PPe-S-1 and PPe-S-2) using Caenorhabditis elegans as model organism. The results showed that PPe-S-2 had a notable antioxidant effect, and could significantly enhance the activities of antioxidant enzymes including superoxide dismutase (SOD) (P < 0.01), catalase (CAT) (P < 0.01) and glutathione reductase (GR) (P < 0.05), and increase the level of glutathione (GSH) (P < 0.01), and decreased the content of malondialdehyde (MDA) (P < 0.05). PPe-S-2 could significantly extend the survival time of C. elegans (P < 0.01), which were stress-induced by hydrogen peroxide and methyl viologen. PPe-S-2 was a heteropolys accharide composed of glucose, arabinose, rhamnose and galactose with the molar ratio of 1.00:0.03:0.02:0.14. The molecular weight of PPe-S-2 was 0.73 kDa detected by high performance liquid chromatography.These studies demonstrated that PPe-S-2 obtained by the acid hydrolysis of PPe had a prominent protective effect to the damage induced by the intracellular free radical generating agents.

Growing cancer cells are addicted to glutamine. Glutamate dehydrogenase 1 (GLUD1) is one of key enzymes in glutamine metabolism and plays a critical role in the malignancy of diverse tumors. However, its role and molecular mechanism in clear cell renal cell carcinoma (ccRCC) development and progression remain unknown. In this study, analysis results of the GEO/TCGA/UALCAN database showed that GLUD1 level was downregulated in ccRCC tissues. Immunohistochemistry and western blotting results further validated the downregulation of GLUD1 level in ccRCC tissues. GLUD1 level was gradually decreased as ccRCC stage and grade progressed. Low GLUD1 level was associated with a shorter survival and higher IC50 value for tyrosine kinase inhibitors (TKIs) in ccRCC, reminding that GLUD1 level could predict the prognosis and TKIs sensitivity of ccRCC patients. High level of methylation in GLUD1 promoter was positively correlated with the downregulation of GLUD1 level and was negatively correlated with survival of ccRCC patients. GLUD1 overexpression suppressed RCC cell proliferation, colony formation and migration by inhibiting PI3K/Akt/mTOR pathway activation. Low GLUD1 level correlated with suppressive immune microenvironment (TIME) in ccRCC. Together, we found a novel tumor-suppressing role of GLUD1 in ccRCC which was different from that in other tumors and a new mechanism for inhibiting PI3K/Akt/mTOR activation and TIME in ccRCC. These results provide a theoretical basis for GLUD1 as a therapeutic target and prognostic marker in ccRCC.

With the wide application of the filling mining method, it is necessary to consider the influence of rock activity on the filling body, reflected in the laboratory, that is, the influence of loading rate. Therefore, to explore the response characteristics of loading rate on the mechanical and damage characteristics of aeolian sand paste filling body, DNS100 electronic universal testing machine and DS5-16B acoustic emission (AE) monitoring system were used to monitor the stress–strain changes and AE characteristic parameters changes of aeolian sand paste filling body during uniaxial compression, and the theoretical model of filling sample damage considering loading rate was established based on AE parameters. The experimental results show that: (1) With the increase in loading rate, the uniaxial compressive strength and elastic modulus of aeolian sand paste-like materials (ASPM) specimens are significantly improved. ASPM specimens have ductile failure characteristics, and the failure mode is unidirectional shear failure → tensile failure → bidirectional shear failure. (2) When the loading rate is low, the AE event points of ASPM specimens are more dispersed, and the large energy points are less. At high loading rates, the AE large energy events are more concentrated in the upper part, and the lower part is more distributed. (3) The proportion of the initial active stage is negatively correlated with the loading rate, and the proportion of the active stage is positively correlated with the loading rate. The total number of AE cumulative ringing decreases with the increase in loading rate. (4) Taking time as an intermediate variable, the coupling relationship between ASPM strain considering loading rate and the AE cumulative ringing count is constructed, and the damage and stress coupling model of ASPM specimen considering loading rate is further deduced. Comparing the theoretical model with the experimental results shows that the model can effectively reflect the damage evolution process of ASPM specimens during loading, especially at high loading rates. The research results have significant reference value for subsequent strength design of filling material, selection of laboratory loading rate and quality monitoring, and early warning of filling body in goaf.

Metabolic reprogramming is the prominent feature of clear cell renal cell carcinoma (ccRCC). Succinate dehydrogenase subunit B (SDHB) is one of subunits of mitochondrial respiratory chain complex II. The loss of SDHB function is closely related with metabolic changes in kidney cancer cells. However, the role and molecular mechanism of SDHB in ccRCC occurrence and progression are still unclear. In this study, the results of bioinformatics analyses on GEO, TCGA and oncomine databases and immunohistochemistry showed that the expression level of SDHB was downregulated in ccRCC tissues. SDHB level was gradually downregulated as ccRCC stage and grade progressed. The low level of SDHB was associated with poor prognosis of ccRCC patients, especially for advanced ccRCC patients. Increased methylation levels in SDHB gene promoter led to the downregulation of SDHB level in ccRCC tissues. SDHB was correlated with many metabolism related genes and its interacting proteins were enriched in metabolic pathways. SDHB overexpression suppressed the proliferation, colony formation and migration of ccRCC cells by inhibiting aerobic glycolysis. SDHB may be a potential prognostic marker and therapeutic target for ccRCC.

Filling mining is an important direction in green coal mining. In the filling site, a layered filling body can be formed due to technological problems. In this paper, we take Shanghe Coal Mine (Shaanxi Province, China) as the background. In order to explore the mechanical properties and failure modes of layered backfill, specimens with different layered proportions (1:1, 1:3, 3:1) were made and studied concerning the aspects of wave velocity, porosity, strength and failure modes. The experimental result demonstrates that with the increase of curing time and fly ash (FA) content, the porosity of ASPLB decreases, the wave velocity and the strength increases. In addition, the layered structure has a significant effect on the strength and failure mode of the specimen. Uniaxial compression experiments showed that after 28 days of curing with Ratio III, the strength of layered backfill (LB) was reduced by 14% and the strength of 3:1 LB was increased by 16.7% and 40% compared with 1:1 LB and 1:3 LB, respectively. A digital speckle experiment showed that the failure mode of ASPLB is a vertical fracture without penetration, and the fracture propagation of layered ASPLB is hindered by the stratification. Based on the above research, the scheme that meets the requirements of the Shanghe Coal Mine is determined, and its reliability is verified, providing guidance for scientific stratification and the filling of gob.

Backfill mining is the most environmentally friendly mining method at present, which can effectively control the surface subsidence, improve the recovery rate, and has good social and economic benefits. The purpose of this study is to solve the environmental problems caused by solid waste, combined with the rich geographical advantages of aeolian sand in the Yushenfu mining area of China. The rheological properties of the aeolian sand-fly ash-based filling slurry with different fly ash content are studied by experiments, and the strength development law of the filling body under different age and fly ash content are studied from the macroscopic and microscopic points of view. The rheological experiments showed that the increase of the amount of fly ash has a significant effect on the thixotropy, plastic viscosity, and yield stress of the filling slurry. Additionally, rheological properties of aeolian sand-fly ash-based filling slurry conform to the Bingham model. With the increase of the amount of fly ash, the performance of the filling slurry has been significantly improved. Uniaxial test and scanning electron microscope observation showed that the influence of fly ash on the strength of the filling body was mainly reflected in the late stage of maintenance, but was not obvious in the middle stage. Fly ash particles mainly bear the role of “water reduction” and a physical filling effect, which makes the filling slurry thicker and the internal structure more closely spaced. The volcanic ash reaction of fly ash is lagging behind the hydration reaction of cement; the secondary product of the delayed reaction is filled in the pores of cement hydrates, which can greatly reduce the porosity of the backfill body and increase the later strength of the backfill body. It provides a guarantee for the safe replacement of coal pillars in the working face.

During strip backfilling mining in coal mines, the backfilling material is the main support structure. Therefore, studying the pressure law of the backfilling material is essential for the safe and efficient mining of coal resources. Based on research into strip backfilling mining at working face number 3216 of the Shanghe Coal Mine, and to smooth transition of overlying strata loads to the backfilling material, this study proposes a three-stage strip backfilling mining method. Based on thin-plate theory, an elastic thin-plate model, a reasonable spacing of strip mining is constructed, and the reasonable mining parameters of “mining 7 m to retain 8 m” at working face number 3216 of the Shanghe Coal Mine are determined. The law of backfilling pressure in three-stage strip backfilling mining is studied through numerical simulation and physical simulation experiments. The results show that field measurement results are basically consistent with the experimental results and numerical simulation results. When three-stage strip backfilling mining is adopted, the stage-one backfilling material is the main bearing body to which the overlying rock load transfers smoothly and gradually, and the structure of the “overburden-coal pillar (or backfilling strip)” in the stope remains stable. In three-stage strip backfilling mining, the overlying rock load is ultimately transferred to the stage-one backfilling material, the stage-two backfilling material is the auxiliary bearing body, and the stage-three backfilling material mainly provides long-term stable lateral support for the stage-one backfilling material.