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Abstract Cities are main carbon emissions generators. Land use changes can not only affect terrestrial ecosystems carbon, but also anthropogenic carbon emissions. However, carbon monitoring at a spatial level is still coarse, and low-carbon land use encounters the challenge of being unable to adjust at the patch scale. This study addresses these limitations by using land-use data and various auxiliary data to explore new methods. The approach involves developing a high-resolution carbon monitoring model and investigating a patch-scale low-carbon land use model by integrating high carbon sink/source images with the Future Land Use Simulation model. Between 2000 and 2020, the results reveal an increasing trend in both carbon emissions and carbon sinks in the Shangyu district. Carbon sinks can only offset approximately 3% of the total carbon emissions. Spatially, the north exhibits net carbon emissions, while the southern region functions more as a carbon sink. A total of 14.5% of the total land area witnessed a change in land-use type, with the transfer-out of cropland constituting the largest area at 96.44 km2, accounting for 50% of the total transferred area. Land-use transfer resulted in an annual increase of 77.72 × 104 t in carbon emissions between 2000 and 2020. Through land-use structure optimisation, carbon emissions are projected to increase by only 7154 t C/year from 2000 to 2030, significantly lower than the amount between 2000 and 2020. Further low-carbon land optimisation at the patch scale can enhance the carbon sink by 129.59 t C/year. The conclusion drawn is that there is considerable potential to reduce carbon emissions through land use control. The new methods developed in our study can effectively contribute to high-resolution carbon monitoring in spatial contexts and support low-carbon land use, promoting the application of low-carbon land use from theory to practice. This will provide technological guidance for land use planning, city planning, and so forth.

Mineral resources are essential to human life and social development and play an important role in national security and economic development. China has huge reserves of metal mineral resources, but the per capita possession is low. Especially, it is difficult for iron, copper, aluminum, and other metal mineral resources to be self-sufficient and heavily dependent on foreign countries. Because of the massive exploitation of metal mineral resources, shallow resources are becoming exhausted, and deep mining will become the main force for the supply of metal mineral resources in the future. “Going deep into the earth” corresponds to the current state of national resource strategy development. It is found that there is still a certain gap between China’s deep metal mining technology and mining depth compared with internationally developed mining countries. The mining depth of foreign mining countries is mostly over 3000 m, with three South African mines having a mining depth of over 4000 m, whereas the mining depth of Chinese mines is mostly below 2000 m, and most of the metal mines have not yet broken through the kilometer depth. Furthermore, the level of mining technology in established mining countries abroad is high, and the degree of mechanization and intelligence is high. Deep mining technology in China is insufficient to meet the need for deep mining. China still has a large gap compared with internationally developed countries; therefore, the related rock mass mechanics theory and mining technology are no longer suitable for deep metal mining. In this paper, we summarize the research status of four major theories and technologies for deep mining of metal mines, namely, deep rock mechanics, deep well building and lifting, green mining, and intelligent mining, and proposes future research emphases. Finally, based on the research status and existing problems of the key technologies and theories of deep metal mining at present, the paper puts forward three strategic ideas: deep-part construction of a super-large intelligent autonomous mine, in-situ fluidized mining, and rock mechanics. With the continuous increase of mining depth, it is urgent to study the related theory and technology of deep mining of metal mines so as to ensure the safe, efficient, economical, and environmentally friendly mining of deep metal mineral resources and ensure the resource security of our country.

High-concentration tailings pastes are commonly encountered in the surface deposition and underground cemented paste backfill. It is necessary to forecast the pressure loss along the pipe and the flow behavior in the mined-out area when tailings pastes are transported in a pipeline or stored up in goaf. Traditionally, thixotropy has often been overlooked while designing tailings paste transport and disposal systems due to the complexity of thixotropy characterization. However, thixotropy plays an essential role in the rheology of tailings pastes. To achieve the accurate representation of thixotropy, a suitable constitutive model has to be selected in advance. Unfortunately, there is no current available thixotropic model for tailings pastes up to date. Moreover, tailings pastes exhibit complex thixotropy that is significantly affected by the particle size of tailings, though the relevant studies are not abundant. It is important to analyze quantitively the relationship between particle size and thixotropic parameters based on an appropriate constitutive model. In this work, the constitutive thixotropic model for tailings pastes proposed by Zhang et al. was adopted. To reveal the influence of particle size on the thixotropy of tailings pastes, samples of various mean particle sizes prepared from the same tailings were applied to constant shear rate experiments. Results show that the target tailings pastes display significant thixotropy, leading to shear thinning under steady shear rates. In the steady state, the static yield stress, dynamic yield stress, and Bingham viscosity appear to correlate linearly to the reciprocal of the square of the mean particle size. As for the transient state, the corresponding fit parameters show a strong linear dependence on the mean particle size. The proposed equilibrium and thixotropic models are valid. The forecasting models for equilibrium and transient shear stress are established based on data fit, which is attributed to the quantitative characterization of steady-state and transient rheology for thixotropic tailings pastes under the effect of particle size.

Context Moringa oleifera Lam. (Moringaceae) (MO) is an important food plant that has high nutritional and medical value. However, there is limited information on whether its seeds can improve sleep.Objective This study investigated the effects of MO seed ethanol extracts (EEMOS) on sleep activity improvement and examined the underlying mechanisms.Materials and methods Male ICR mice were placed into six groups (n = 12) and treated as follows: Control (sodium carboxymethyl cellulose, 20 mL/kg), estazolam tablets (2 mg/kg), EEMOS (1, 2 g/kg) and kaempferol (1, 2 mg/kg). These samples were successively given intragastric for 14 d. Locomotor activity assay, pentobarbital-induced sleeping and pentetrazol-induced seizures tests were utilized to examine the sedative-hypnotic effects (SHE) of EEMOS.Results Compared with the control group, the results revealed that EEMOS (2 g/kg) and KA (2 mg/kg) possessed good SHE and could significantly elevate the levels of γ-aminobutyric acid and reduce the levels of glutamic acid in the mouse hypothalamus (p 0.05). Additionally, they cause a significant increase in Cl- influx in human cerebellar granule cells at a concentration of 8 µg/mL (p < 0.05).Discussion and conclusions These findings demonstrated that EEMOS could improve sleep by regulating GABAA-ergic systems, and encourage further clinical trials to treat insomnia.

To investigate the early hydration and consolidation mechanism of superfine metal tailings powder in the CaO–CaSO4–H2O system, a clinker-free consolidation material based on iron tailings powder was prepared by superfine grinding lime, gypsum, and iron tailings. From 3 min to 24 h, the liquid phase of the hydrated slurry was extracted by centrifugation and high-pressure extraction. The changes in ion concentration and conductivity were tested, and the relationship between them was analyzed. The relationship between the formation mechanism of early hydration products of a consolidated body and the change of liquid phase characteristics is studied combined with the hydration exothermic rate curve, field emission scanning electron microscope (SEM), X-ray diffraction analysis (XRD), thermogravimetry-differential thermal analysis (TG–DSC), and other test methods. The results show that lime, gypsum, and amorphous components, which are on the surface of iron tailings powder, dissolve rapidly within a few minutes after solid-liquid mixing. The concentration of each ion in the liquid phase rises sharply, reaching the peak or saturated state successively in 10–30 min, and then decreases rapidly. After 180 min, the decline rate slows down but continues to decline. The liquid conductivity has a very high positive correlation with the total concentration of Ca2+, OH–， and SO42– ions; The first hydration exothermic peak of the consolidated material is concentrated within 0–15 min, which is mainly caused by the wetting and dissolution of soluble components in the consolidated material and the exothermic behavior of lime hydration; The starting and ending time of the second hydration exothermic behavior is 20–180 min, which is mainly caused by the phase change heat generated by the formation of hydration products. Increasing the grinding time significantly prolongs the termination time of the second exothermic behavior and increases its peak value; The phase analysis of hydration products showed that AFt characteristic peak and C–S–H endothermic peak could be seen in the slurry after hydration for 90 min. Research has proved that the amorphous SiO2 and Al2O3 on the surface of superfine iron tailings powder have the characteristics of rapid dissolution in alkaline solutions, and a hydration reaction can occur when lime and gypsum components are encountered. When the solubility product of hydration products is reached, hydration products AFt and C–S–H will be generated. The two hydration products are interspersed and cemented with each other, and the unhydrated iron tailings particles will be consolidated to form a hardened body. Prolonging the grinding time can effectively increase the system’s amorphous SiO2 and Al2O3 content and the proportion of superfine particles in iron tailings, thus improving the slurry hydration rate. While increasing the amount of the hydration product, the filling effect of the micro powder part is further increased, and the strength of the consolidated body is correspondingly improved.

Hemihydrate phosphogypsum (HPG), as a cementing material for mine filling, will spontaneously transform into phosphogypsum (PG) in the stockpiling state. The gelling activity decreases, and meeting the requirements of mechanical properties required for long-distance mine filling becomes difficult. The key measure in expanding the industrial application radius of HPG as a filling cementitious material is the prevention of the spontaneous conversion of HPG to PG. In-depth research on the conversion process of HPG in the storage state is required to achieve a breakthrough in the HPG resource utilization technology. In the storage process, the HPG chemical reaction will release the heat of hydration, causing the temperature and chemical fields in the system to interact with each other and promote the conversion of HPG to PG. Therefore, the HPG hydration heat release process is accurately calculated, analyzed, and simulated. This is a prerequisite to effectively inhibit the conversion of HPG. This article seeks a model of the heat release of the HPG hydration reaction during the storage process to understand the change of its gelation performance and guide on-site industrial applications. The monitoring of the free water mass fraction and the temperature of HPG stacks with initial temperatures of 35 °C, 40 °C, 60 °C, and 80 °C reveals that the HPG free water mass fraction change law conforms to the first-order reaction kinetic model. Based on thermodynamics and chemical reaction kinetics, a thermal kinetic model of the HPG hydration reaction on the relationship between the storage temperature and time is proposed. Using the COMSOL Multiphysics numerical simulation software, the HPG hydration reaction thermokinetic equation was then embedded in the heat transfer and ODE modules, and the HPG reactor temperature was numerically simulated. The simulated reactor temperature curve was more consistent with experimental results, and the reliability of the proposed model was verified. This model can provide guidance for the later design of the delaying HPG conversion plan and has very important practical significance for the promotion and application of HPG.

Abstract Introduction Calcaneal fractures, especially those involving the articular surface, should be anatomically reduced as much as possible. Fixing the fracture by placing a screw into the sustentaculum tali from the lateral side of the calcaneus is generally considered to be the key to successful surgery. However, due to the limited visibility during surgery, it is not easy to place screws into the sustentaculum tali accurately. The purpose of this study was to explore a new fluoroscopy method for the sustentaculum tali and verify the value of this method in improving screw placement accuracy. Methods In this study, a total of 42 human foot and ankle specimens were dissected and measured. The shape and position of the sustentaculum tali were observed, and the influence of adjacent bones on imaging findings was analysed. The axial and frontal X-ray fluoroscopy method to view the sustentaculum tali was formulated, and the appropriate projection angle through anatomical and image measurements was explored. Thirty specimens were randomly selected for screw placement, and the direction of the screw was dynamically adjusted under the new imaging method. The success rate of sustentacular screw placement was evaluated. Results The anteversion angles of the sustentaculum tali were 30.81 ± 2.21° and 30.68 ± 2.86° by anatomical and imaging measurements, respectively. There was no statistically significant difference in the anteversion angle between the two measurement methods. Harris heel views should be obtained at 30° to identify the sustentaculum tali on axial X-ray images. Frontal X-ray imaging was performed perpendicular to this projection angle. Through frontal and axial X-ray imaging, the position and shape of the sustentaculum tali can be clearly observed, and these factors are seldom affected by adjacent bones. Under the new fluoroscopy method, the screws were placed from the anterior region of the lateral wall of the calcaneus to the sustentaculum tali. A total of 60 screws were placed in the 30 specimens; of these, 54 screws were in good position, 2 screws penetrated the cortical bone, and 4 screws did not enter the sustentaculum tali. The success rate of sustentacular screw placement was 90% (54/60). Conclusions Axial and frontal X-ray images of the sustentaculum tali can clearly show the shape of the structure, which improves sustentacular screw placement accuracy.

Background: Aberrant epigenetic and transcriptional events that drive cancer progression could be precisely targeted. We aimed to uncover the epigenetic roles of RBBP7 on breast cancer (BCa) stemness and metastasis. Methods: The bioinformatic analysis was used to assess the clinical significance of RBBP7 in BCa. CCK8, colony formation, and Transwell assays were utilized to estimate the oncogenic functions of RBBP7. The ChIP-qPCR and dual-luciferase reporter assays were used to investigate the epigenetic mechanisms of RBBP7. Tumor sphere formation assays were conducted to assess the self-renewal abilities of BCa cells. Tail vein injection models were constructed to assess the in vivo metastatic efficiency of BCa cells. The PDOs and PDX models were used to assess the clinical significance of ORY-1001 in suppressing BCa. Results: Here, we found that RBBP7 is upregulated in BCa and associated with poor prognosis. Functional experiments demonstrated that RBBP7 enhanced BCa proliferation and distal metastasis. Mechanistically, a novel RBBP7-super-enhancer (SE) was identified using multiple databases in BCa. RBBP7-SE sustained high levels of RBBP7 and CRISPR/Cas9-mediated deletion of SE decreased RBBP7 levels and suppressed BCa malignant features. Further, our data showed that RBBP7 may correlate with stemness pathway and significantly potentiated BCa cancer stem-like properties. Additionally, RBBP7 interacts with LSD1 and relies on LSD1 to erase suppressive H3K9me3 markers in promoters of downstream stemness targets (SOX9/SOX2/OCT4/CCND1). Thus, RBBP7 recruits LSD1 to transcriptionally upregulate the expressions of key stemness genes, and promote tumor stemness capacity. Pharmacological inhibition of LSD1 by ORY-1001 effectively repressed RBBP7-high BCa tumor growth, stemness properties, and distant metastasis. Conclusions: Together, our results establish that the SE-RBBP7-LSD1 axis represents a potential therapeutic target for BCa treatment. [ABSTRACT FROM AUTHOR]

Whether domestic or foreign, the utilization of phosphogypsum (PG) resources is not satisfactory. A chemical plant in Guizhou produces phosphoric acid through a semi-aqueous process to obtain the byproduct hemihydrate phosphogypsum (HPG), which has a certain gelling activity. If this feature of HPG can be fully utilized, it can replace cement as a cementing material to prepare mine-filling materials. Utilizing HPG for goaf filling can not only reduce the environmental protection problems caused by the surface discharge of PG but also eliminate the hidden safety hazards in the goaf. At present, when HPG is used to prepare mine-filling cementitious materials, HPG will be consolidated into a block and lose its gelling activity when it is stacked for a certain period of time. The gelling performance of the HPG in the storage state appears to decline. Based on the indoor HPG crystal water detection and uniaxial compression test and setting four different storage temperatures (20 ℃, 40 ℃, 60 ℃, and 80 ℃), this study explored the changes in the mass fraction of the crystal water of HPG samples under different storage temperatures. The compressive strength development law of HCM prepared after storage and microscopic analysis methods, such as scanning electron microscopy, were used to study the influence mechanism of the storage temperature on its strength. Results show that the stacking temperature has a significant effect on the gelling performance of HPG. A high stacking temperature will speed up the conversion of free water in the HPG sample to crystal water and inhibit the strength development of the HCM prepared after stacking. Data standardization was used to predict the compressive strength of samples after storage at different temperatures, which is confirmed to be in good agreement with the measured values. The microscopic analysis found that the storage temperature mainly affects the supersaturation of the system, and the microscopic morphology of the HCM prepared after storage at different temperatures is different.

Tailings and waste rock produced in metal mines are the most common industrial solid wastes all over the world, resulting in serious environmental and safety issues. Cemented paste backfill (CPB) is widely used for tailings management and stope treatment. CPB of total solid waste (TSW-CPB) was proposed on the basis of CPB of full-tailings. In the TSW-CPB process, thickened full-tailings, waste rock, and slag are mixed to prepare a paste that is filled into the stope. TSW-CPB can avoid the collapse of a stope, failure of the tailings storage facility, and landslide of a waste-rock yard, achieving the goal of “total waste to cure three harms.” The effects of solid fraction (SF), waste rock dosage (WRD), and glue powder dosage (GPD) on the slump (S), yield stress (τ0), uniaxial compressive strength (UCS), and bleeding rate (BR) were investigated through orthogonal experiments. According to the scope of technical indicators specified in the National Standard of the People’s Republic of China “Technical specification for the total tailings paste backfill (GB/T 39489—2020),” the overall desirability function approach was used to conduct multiple response optimization of key TSW-CPB performance indicators. TSW-CPB was shown to have similar fluidity, transportation performance, mechanical properties, and bleeding performance to the CPB of full-tailings. The SF, WRD, and GPD affect the S, τ0, UCS, and BR of TSW-CPB considerably. The SF has the most important influence on S and τ0, while GPD has the most substantial impact on UCS and BR. Multiple response optimization yielded SF = 79.31%, WRD = 18.86%, and GPD = 3:20, with S = 25.45 cm, τ0 = 100.49 Pa, UCS = 3.55 MPa, and BR = 1.50% as the corresponding responses. The optimal results can provide references for practical application, and the overall desirability function approach can be used in other mines to optimize multi objective CPB.

In the future, the output of ultrafine full tailings will explode due to the massive mining of low-grade deposits and demand for the recovery of useful minerals. The best way to dispose of ultrafine full tailings is to prepare them into the paste for filling underground voids or surface stacking. The deep cone thickening of ultrafine full tailings is a key link of tailings paste disposal technology. In the thickening process of ultrafine full tailings, slow sedimentation velocity, high dosage of flocculant, excessive overflow turbidity, and low underflow concentration are the bottlenecks that restrict the application of disposal technology for ultrafine full tailings paste. To investigate the thickening characteristics of ultrafine full tailings, the sedimentation test in measuring cylinder, the small-scale and semi-industrial deep cone dynamic thickening tests were carried out. Results show that the nonionic flocculant with a molecular weight of 12 million is most beneficial for the settlement of the tailings. With increasing flocculant dosage, the turbidity of overflow decreases and underflow concentration remains unchanged. Upon increasing the solid flux, the turbidity of overflow increases and underflow concentration decreases. In particular, when the solid flux is 0.4 t·m−2·h−1, the feeding solid mass fraction is 12%, flocculant dosage is 50 g·t−1, and average solid mass fraction of the underflow of the small-scale and semi-industrial dynamic thickening test is 62.8% and 74.4%, respectively. Mud height has a significant influence on the underflow concentration. The solid mass fraction of the underflow of the deep cone thickener increases with the increasing mud height, and this process conforms to the DoseResp function. This growth process can be divided into three stages: (1) slow growth (mud height 1–4 m), (2) rapid growth (mud height 4–7 m), and (3) basic stable (mud height over 7–8 m). This is related to the compression performance of the tailings flocs at different mud heights. According to the function relation between the underflow concentration and mud height, the mud height can be adjusted to meet the required underflow concentration for underground backfilling.

In China, solid waste backfill technology has been used in metal mines for more than half a century. It has been essential for comprehensive excavation and utilization of mineral resources, environmental protection, and engineering safety. The core concept of solid waste filling has not changed qualitatively despite the rapid development of mining technology from semi-mechanized and mechanized automation and intelligence. It is mainly used in mine tailings, waste rock, and other solid wastes to control the hazards of goaf and tailings reservoir from the source to treat waste and hazards. However, the quality requirements, degree of fine control, and intelligent allocation technology of solid waste filling are undergoing considerable changes. Furthermore, the design philosophy of modern backfill technology consider comprehensive realization of solid waste utilization, environment conservation, mined-out area disposal, resource recovery, and ground pressure control that require optimal backfill method, sufficient mechanical strength, and pumpable backfill slurry, using information technology, automatic technology, and equipment technology. Besides, new backfill concepts are introduced, such as collaborative paste and multimaterial, synchronous, and functional backfills. In this paper, the framework of backfill mechanics was described, relying on rheology and solid mechanics. The influences of in-situ multifield factors were analyzed based on the characteristics of the in-situ stope, introducing the latest multifield coupling monitoring system. More details about the development trend and research status of critical processes in the backfill, including deep thickening, mixing, and long-distance pipe transport, have been updated. We propose a picture for the future development of intelligent backfill based on the advantages of intelligent backfill and performance of intelligent algorithms in the backfill field. In terms of the future trend of solid waste backfill, we feel that it can enrich green mining, explore the realization of modular, scale, and intelligent backfill, and actively examine and serve the needs of deep mining. Thus, the backfill method appears as the optimal choice for deep mining and green mining.

Background: Dexmedetomidine (DEX) reportedly protects against ischemia-reperfusion (I/R) injury and associated damage to the kidneys, but the underlying mechanisms have yet to be established. Methods: Unilateral nephrectomy was performed in Wistar rats, and the remaining kidney was clamped for 1 h prior to reperfusion to establish an experimental model system. These animals were then randomized into Sham, DEX + Sham, DEX + I/R, ATI (Altepamizole, α2-adrenergic receptor inhibitor) + DEX + I/R, and 3-MA (3-methyladenine, autophagy inhibitor) + DEX + I/R groups. Serum renal function biomarkers, acute kidney injury (AKI) histopathological scores, serum inflammatory factors, redox biomarkers, markers of autophagic flux, and autophagosome numbers were assessed. Levels of proteins related to the autophagic pathway, including mTOR and AMPK, were also analyzed. Results: Serum creatinine and urea nitrogen levels in the I/R group were significantly elevated over those in sham control rats, as were AKI scores, serum inflammatory cytokine concentrations (IL-6, IL-1β, and TNF-α), and serum levels of the oxidative stress biomarker malondialdehyde (MDA). All of these parameters were significantly reduced in the DEX + I/R group relative to I/R model rats. I/R group rats also exhibited significant decreases in renal levels of autophagic flux-related biomarkers and autophagosome numbers relative to sham controls, while DEX administration partially restored normal autophagic flux in these rats. Acute I/R also suppress the expression of AMPK in the kidney while increasing mTOR expression, and DEX reversed these effects. The beneficial impact of DEX on I/R-associated AKI was ablated by ATI or 3-MA administration. Conclusions: These analyses provide strong evidence for the ability of DEX to protect against I/R-associated AKI via the α2-AR/AMPK/mTOR pathway-mediated enhancement of autophagic activity.

The real-time inline monitoring technologies of focused beam reflectance measurement (FBRM) and particle video microscopy (PVM) were used to analyze the aggregate structure evolution during the operation of a dynamic thickening system. The tailings dewatering studies were performed under two series of conditions: (i) rake rotation speeds of 0, 0.1, 1, and 10 r·min−1 and an initial mud bed height of 75 cm and (ii) initial mud bed heights of 75, 45, and 25 cm and a rake rotation speed of 0.1 r·min−1. The aggregate diameter, particle size distribution, and real-time images of the tailings thickening process were obtained. The results show that with the increase in the shearing time, the diameter and counts of aggregate first increase, then decrease, and then become stable. According to the aggregate diameter variation, the aggregate evolution can be divided into three stages: growth, reconstruction, and densification periods. The condition of a shear rate of 0.1 r·min−1 and an initial mud bed height of 75 cm has the best effects on the aggregate growth, structure breaking acceleration, aggregate reconstruction, and aggregate densification improvement, as determined in the laboratory; however, high shear rate has a degrading effect on the aggregate structure evolution. The aggregate diameter progressively decreases with the increase in the shear rate. The longer the aggregate growth period, the larger the maximum aggregate diameter, and a longer reconstruction period is observed at higher initial mud bed heights. Moreover, the aggregate diameter increases with the increase in the initial mud bed height. The fractal dimension of tailings aggregate reflects the change characteristics of the aggregate structure. According to the calculation of fractal dimension and porosity of the PVM image, the dynamic equilibrium relastionship between the breaking force and cohesive force of aggregates was analyzed, the influence on the aggregate breaking was analyzed. The aggregate densification rule in the tailings thickening process was revealed analyzed, based on the dynamic equilibrium relationship between the breaking force and cohesive force of aggregates.

With the advantages of efficiency and economy, deep-cone thickener (DCT) has been increasingly applied in tailings management. The rake in the DCT is essential for obtaining high-concentration underflow slurry; thus, more emphasis was placed on the effects of rakes on the underflow concentration. However, high concentration means high yield stress, which may lead to rake blockage. Therefore, this study investigated the effects of flocculation and sedimentation on the yield stress of thickened ultrafine tailings slurry. First, flocculation and sedimentation experiments were conducted under a pH range of 8 to 11 and flocculant dosage of 0 to 45 g·t−1 to obtain different thickened ultrafine tailings slurries. Then, the yield stress was measured through an in situ test. Finally, the amount of flocculant adsorbed on the tailings particle surface was analyzed by total organic carbon analysis. The amount of flocculant adsorbed on the tailings particles surface increased with the pH and flocculant dosage over the entire experiment range. Then, the yield stress increased with the increase in the amount of adsorbed flocculant, indicating that flocculation sedimentation has a significant influence on the yield stress. Based on the flocculation sedimentation behavior and yield stress, the optimal conditions were a pH of 8 and flocculant dosage of 15 g·t−1. Under these conditions, the initial settling rate of the solid–liquid interface was 0.4565 mm·s−1, supernate turbidity was 143 NTU, solid mass fraction of sediment was 51.56%, and yield stress was 243.18 Pa. The relationship between yield stress and the amount of flocculant adsorbed and yield stress was investigated, and an empirical model for yield stress based on flocculant adsorption was established. It was found that the yield stress increased with the amount of flocculant adsorbed, providing a reference for the control of flocculation sedimentation parameters in actual production.

Tailings thickening is an important process of paste filling technology. At present, a deep cone thickener is often used for tailings thickening. The sedimentation rate of tailings affects the solid flux of the deep cone thickener and determines the area occupied by the deep cone thickener. At present, the addition of flocculant to tailings has become a common practice to improve the efficiency of tailings thickening. Thus, the influence of various factors on the solid flux of the deep cone thickener needs to be investigated. In this study, the solid flux of the deep cone thickener was calculated through the static sedimentation experiment of the graduated cylinder, and the influence law of the flocculant unit consumption and slurry concentration on the solid flux of the deep cone thickener was analyzed, and the influence of the two factors on the solid flux of the deep cone thickener was determined. Results showed that the tailings exhibit a quadratic function relationship when the flocculant unit consumption is 5–30 g·t−1. At 6%–26% solid mass fraction of slurry, the solid flux first increases and then decreases, which is consistent with the experiment. The regression analysis of the solid flux equation under the coupling effect of flocculant unit consumption and slurry concentration shows that the contribution of the two factors to solid flux is slurry concentration > flocculant unit consumption. Based on the analysis of the influence of flocculant unit consumption and slurry concentration on solid flux, the reasons for the different contribution values of flocculant unit consumption and slurry concentration were summarized. According to the mathematical relationship between flocculant unit consumption, slurry concentration, and solid flux obtained from the research, engineering suggestions for the design and operation of the deep cone thickener were proposed. During the operation of the deep cone thickener, the slurry concentration should be guaranteed first, followed by the flocculant unit consumption.

Glaucoma is a common blinding eye disease characterized by progressive loss of retinal ganglion cells (RGCs) and their axons, progressive loss of visual field, and optic nerve atrophy. Autophagy plays a pivotal role in the pathophysiology of glaucoma and is closely related to its pathogenesis. Targeting autophagy and blocking the apoptosis of RGCs provides emerging guidance for the treatment of glaucoma. Here, we provide a systematic review of the mechanisms and targets of interventions related to autophagy in glaucoma and discuss the outlook of emerging ideas, techniques, and multidisciplinary combinations to provide a new basis for further research and the prevention of glaucomatous visual impairment.

To achieve the ultimate goal of carbon neutralization by 2060 in China, increasing carbon sequestration has become more important. Based on satellite images, field observations and spatial econometric models, this study examined vegetation coverage and carbon sequestration changes during the period 2000–2020 in China’s eight forestry engineering projects area, analysed their correlation, and compared their response to climate change. The results show that there was a significant turning green trend in all regions. The NDVI with an increasing trend accounted for 68.5 % of the whole study area, which were widely distributed and especially significant in the south. The NDVI with a decreasing trend were more concentrated in the north. For NEP, 31.44 % of the total study area showed decreasing trend, which had a wide distribution and more concentrated in the south and the coastal regions of China. NEP under increasing trend were more obvious in the centre and north of China. In time series, 77.85 % of NDVI in the total study area positively correlated with NEP, with the average correlation coefficient of R = 0.51 (P > 0.05), and the higher positive correlations were more concentrated in the centre and north of China. For precipitation, 83.32 % and 65.31 % of the total area can promote the increase in NDVI and NEP, with the effect more obvious in the north. For temperature, about half of the total area showed a positive correlation, more obvious in the north, for both NDVI and NEP. Spatially, NDVI changes corresponded well with NEP for most vegetation types, for both precipitation and temperature. The few differences only appeared for broad-leaved forest and coniferous forest changes with average precipitation higher than 50 mm between 2000 and 2020. We draw the conclusion that turning green will increase carbon sequestration, the effect is more obvious in northern China.

To explore the correlation between nurses’ attitude and practice toward physical restraint (PR) in psychiatric settings and identify the factors that influence the use of PR.

Cemented paste backfill (CPB) technology is a significant approach for the development of green mining in metal mines and can provide safe, environmentally friendly, and efficient technical support for deep underground mining. As the theoretical basis of paste backfill, the rheological concepts, characteristics, and models of paste had been systematically reviewed, and the rheological measurement methods were analyzed herein. Rheological measurement enables the quantitative characterization of the rheological behavior of paste, and on this basis, a series of studies, such as the rheological constitutive equations of paste, evaluation of the influence of both internal and external factors on paste rheology, and quality control of CPB, was conducted. Generally, the rheology of paste is influenced by certain constituents, including solids concentration, particle size distribution, density, and cement hydration, and various external conditions, such as shear stress and temperature. The rheological properties of paste differ significantly, and currently, a unified method is not yet available for the rheological measurement of paste. Hence, comprehensive knowledge of rheological measurement is essential to achieve a better combination of rheology and CPB engineering, particularly in consideration of the specific physical and chemical properties of tailings and the common practice in the mining field. Therefore, the principles and applications of commonly used approaches, including the vane rheometer, slump cone, L-shaped tube, inclined pipe, and loop facility, were summarized, with emphasis on the measurement of yield stress because of its influence on the paste, that is, a non-Newtonian fluid. Furthermore, the applicability of the aforementioned measurement methods was comprehensively discussed. Given that rheological measurement has a profound effect on the development of paste rheology theory and paste backfill technology, the key problems were discussed by emphasizing the importance of the establishment of rheological measurement standards and the application of rheological measurement to paste backfill processes in real time. The development trend of research on paste rheology was also explored.