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Phosphorus (P) is a key nutrient for crop growth and yield. The use of drip irrigation systems to apply phosphate fertilizer may enhance the migration distance and improve usage rates. However, emitter clogging poses a substantial challenge to phosphorus drip irrigation systems. In this study, we evaluated the influences of the phosphorus fertilizer type on soil-available phosphorus (P), plant growth, yield, and drip emitter clogging. Experiments were conducted in both seasons using different phosphorus fertilizers, including urea phosphate (UP, F1), monoammonium phosphate (MAP, F2), and a combination of urea phosphate and monoammonium phosphate (UP + MAP, F3). A treatment without phosphate fertigation (F0) was used as the control. Applying phosphorus fertilizers enhanced soil-available P content, increased plant height, and improved the leaf area index (LAI) to a larger extent than those without P fertilizer. This promoted photosynthesis and increased the dry matter mass, plant P and N uptake, and aboveground plant biomass. The maximum yield of 14,764.2 and 14,778.2 kg ha−1 was obtained under urea phosphate (F1) and monoammonium phosphate (F2) in 2022 and 2023 seasons, respectively. Phosphorus fertilization changes the composition and diversity of bacterial and fungal communities in the emitter biofilm. Urea phosphate and monoammonium phosphate increased the abundance of Proteobacteria and decreased the abundance of Acidobacteriota. Acidobacteriota was strongly positively correlated with extracellular protein, whereas Proteobacteria was negatively correlated with extracellular polysaccharides, extracellular protein, and extracellular polymer. The content of extracellular polymer and solid particles decreased by 30.1%–42.0% and 39.8%–79.7%, respectively, inducing a higher relative emitter discharge for the treatment with phosphorus fertilizers. Acidic phosphorus fertilizers, such as urea phosphate and monoammonium phosphate, can maintain the high performance of drip irrigation and produce high crop yield. [ABSTRACT FROM AUTHOR]

Investigating the evolution of land use and its impact on carbon storage is of significant importance for mitigating regional climate change and promoting green low-carbon development. Ningwu County is located in the source region of the Fenhe and Sanggan River, and its ecological status significantly influences the carbon storage (CS) of the watershed ecosystem. In this study, the PLUS-InVEST model was employed to analyze the land use evolution from 1990 to 2020 in Ningwu County, Shanxi Province, as well as their impacts on CS. Additionally, the study simulated and predicted land use changes in Ningwu County by 2040 under four scenarios: natural development (NDS), ecological protection (EPS), cultivated land protection (CLPS), and urban development (UDS), while estimating the corresponding changes in ecosystem CS. Furthermore, the study utilized optimal parameters-based geographical detector to explore the mechanisms underlying the spatial differentiation of CS. The results indicated that the areas of forest land and construction land in the study area consistently increased from 1990 to 2020, whereas the area of cultivated land continuously declined, with grassland, water bodies, and unused land exhibiting a fluctuating increasing trend. The spatial distribution of CS was highest in the northwest, second highest in the southeast, and lowest in the middle region. Over these 3 decades, CS had shown a continuous increase. It is projected that by 2040, the areas of forest and grassland will experience the most significant increase under the EPS; cultivated land only increase under the CLPS; while construction land display the greatest increase under the UDS. Compared to 2020, these four scenarios for 2040 indicate an increase in regional CS, with the EPS showing the largest increment. The primary factors influencing the spatial differentiation of CS in Ningwu County are human activities, followed by topography and climate change; the interactions among these factors exhibit a reinforcing relationship, with the interaction between the distance from construction land and slope having the most substantial impact on the spatial differentiation of CS. [ABSTRACT FROM AUTHOR]

Identifying and evaluating the ecological security pattern (ESP) of region can provide a solid foundation for optimizing regional ecosystem elements and improving regional ecological security. The PLUS model, InVEST model, and circuit theory were used to analyze the ecosystem services and ESP of the Shanxi section of the Yellow River Basin (SYRB) between 2005 and 2035. The findings revealed that 1) The total area of land use shift across categories between 2005 and 2020 was 6,080.99 km2, or 5.22% of the SYRB's total area. Under the natural development scenario, the total land transfer area from 2020 to 2035 was predicted to be 4,605.10 km2. Among these, the tendency for construction and forest land was expanding, while the tendency for cultivated land, grassland, water area, and unused land was shrinking; 2) From 2005 to 2035, the SYRB's water yield and soil conservation all decreased, while the habitat quality and carbon storage showed a declining tendency; 3) The ecological source increased from 35,767.00 km2 in 2005 to 39,931.00 km2 in 2035; the total length of the ecological corridors expanded from 2,792.24 km to 3,553.18 km between 2005 and 2035; the ecological pinch points increased from 27 in 2005 to 40 in 2035; the ecological barrier points increased from 21 in 2005 to 28 in 2035, which show that the ESP remained unstable; 4) According to the ecosystem service characteristics of the SYRB in 2020, an ESP of "one axis, two zones, four corridors, and multiple points" was constructed. This study could provide useful guidance for improving the spatial pattern of land use and maintaining ecosystem services. [ABSTRACT FROM AUTHOR]

Carbon burial patterns in lakes and their dynamic changes significantly impact terrestrial carbon sink fluxes and global carbon budgets. In this study, multi-indicator analysis of sediment core samples (P1, P2, and P3) from Pipahai Lake was conducted. Integrating the chronological sequences of 210Pb and 137Cs, we identified the historical changes and spatial characteristics of total organic carbon (TOC) and inorganic carbon (TIC) burial in Pipahai Lake since 1884. The results show that the TOC content was higher than that of the TIC. They exhibited an increasing trend with decreasing depth. Linear regression results indicated that the variation of TOC is less directly affected by precipitation (R = 0.39) and temperature (R = 0.58), while temperature may have a greater impact on TOC. From 1884 to 1995, nutrients were not the primary factor influencing changes in TOC. The synchronous variation in TIC and TOC contents reflects a higher contribution of external inputs to carbon burial in the Pipahai Lake basin. After 1996, nutrients may have begun to affect variations in TOC. The TOC primarily originates from distal aeolian transport or autochthonous sources, though human activity has played a role in its evolution. The TIC content is controlled by the TOC content and autochthonous sources. This study will contribute to the understanding of the carbon cycling dynamics and their influencing mechanisms in a high-altitude lake ecosystem. [ABSTRACT FROM AUTHOR]

This study aimed to decipher the influence of red mud on the mechanical properties, pore structure, and microstructure of basic magnesium sulfate cements (BMSCs). The results showed that BMSC prepared with an appropriate addition of red mud exhibited improved mechanical properties and yielded the highest compressive strength of 94.54 MPa after curing for 28 days. Adding red mud reduced the total porosity and optimized the pore structure of BMSC. The microstructure and hydration products of the specimens were examined using X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. The results illustrate that the addition of 50% red mud did not affect the amount of the main strength phase 5-1-7 produced in BMSC. It could also reduce the residual amount of MgO and the generation of Mg(OH)2. The red mud and the M-S-H gel generated by the reaction between active SiO2 and α-MgO in the red mud together filled the pore structure of BMSC, making its microstructure denser and higher-strength. This study aims to improve the comprehensive use of red mud, and the results show that red mud can improve the mechanical properties of BMSCs, protecting the environment and simultaneously reducing BMSC production costs to create good economic benefits. [ABSTRACT FROM AUTHOR]

Chlorination has been demonstrated to be an effective method for the prevention and reduction in emitter biological blockage in drip irrigation systems. The injected chlorine dose is generally determined by chlorine concentration at the terminal of the laterals which may lead to a high concentration of residual chlorine at the front of the system and bring detrimental impact to the soil environment and growth of crops, especially in large irrigation units with long laterals. A two-season experiment was undertaken to determine the effects of chlorine disinfection and lateral length on soil NO3-N, enzyme activities, and maize yield under wastewater drip irrigation. The experiments were constructed with lateral lengths ranging from 20 to 80 m and injection chlorine concentrations at the end of laterals ranging from 2 to 6 mg L−1. Lateral length had a major impact on enzyme activities in the partial growth stage, although the effects of lateral length and chlorine concentration on soil nitrogen content and maize yield were negligible. Enzyme activity and soil nitrogen concentration decreased throughout the lateral length as a result of chlorination. A higher detrimental impact on soil characteristics and maize yield is probably going to result from a high concentration of chlorine and a long lateral length mode. The maize yield peaked at L80 with a concentration of 2 mg L−1 chlorine, while it peaked at L40 with 6 mg L−1 chlorine concentration. A chlorination scheme with long lateral length and low chlorine concentration is recommended in consideration of maize yield and minimizing potential negative effects on the soil environment. [ABSTRACT FROM AUTHOR]

A synthetic flocculant of aluminum (Al) and iron (Fe) extracted from red mud (RM) has been widely used in sewage treatment, while the remaining RM residue has been ignored. This study aimed to synthesize polymeric aluminum ferric sulfate (PAFS) flocculant from RM by acid leaching and then use the acidified RM residue to produce an acid RM-based ceramsite (ARMC) by mixing bentonite, hydroxypropyl methylcellulose, and starch. Our results showed that sintering, reaction temperature, H2SO4 concentration, reaction time, and liquid-to-solid ratio had an obvious effect on the leaching of Al and Fe in RM, which was a necessary prerequisite for the efficient PAFS flocculants. At a PAFS dosage of 60 mg/L, turbidity and phosphate removal rates were 95.21 ± 0.64% and 89.17 ± 0.52%, respectively. When the pH value was 8.0, the turbidity and phosphate removal efficiency were 99.22 ± 0.66% and 95.98 ± 1.63%, respectively. Considering the adsorption capacity and mechanical properties, the best conditions for ARMC production included using 60% ARM and ceramsite calcination at 600 °C, with the BET surface area 56.16 m2/g and a pore volume of 0.167 cm3/g. Thermogravimetric analysis indicated that 400 °C was a reasonable preheating temperature to enhance the ARMC mechanical strength, as this temperature allows the removal of surface-adsorbed and constituent water. Under a scanning electron microscope, the ARMC appeared rough before adsorption, while relatively uniform pores occupied it after adsorption. Our conclusion will help to improve the zero-waste strategy of RM and speed up the industrial production of RM in flocculants as well as utilizing ARMC as a new type of adsorbent for phosphorus adsorption in sewage treatment. [ABSTRACT FROM AUTHOR]

It is of great practical significance to identify service blind area, scientifically select park construction areas, and clarify the priority of parks' construction based on the co-ordination of supply-demand evaluation. With the urban parks within the Taiyuan Ring Expressway as the research subjects, we estimated the accessibility range and the service pressure of each park by using the application programming interface of Gaode map route planning and point of interest data to characterize their supply and demand levels. We identified the service blind areas of parks by overlay analysis, and used the location-allocation (LA) model to purposefully supply park green space. Results showed that the accessibility coverage rates of the parks by walking and bicycling within 15 minutes were 35.6% and 71.7%, respectively, indicating insufficient supply capacity of parks. The areas with large potential demand for park green space in Taiyuan were mainly concentrated in the business district of Qinxian-Changfeng Street and the Shuangta business district within Dongzhong ring road, which existed the obviously invisible blind areas. Finally, we proposed new park green space site selection proposal based on LA model. Optimization results indicated that the coverage rates of walking and bicycling within 15 minutes increased to 46.7% and 81.0%, respectively, and that the service pressure of parks was relieved. We combined the leisure demands of urban residents and the distribution of urban parks by utilizing network big data, which could promote the scientific nature and accuracy of the optimizing site selection and provide scientific method and theory basis for urban park construction. [ABSTRACT FROM AUTHOR]

Land use change has a significant impact on the carbon balance in urban ecosystems. Based on the law of land use change in Taiyuan City from 2000 to 2020, this study uses the CA-Markov model to predict the spatial pattern of land use in different scenarios in 2030, and uses the InVEST model to evaluate the carbon storage of Taiyuan City from 2000 to 2030. The results show that from 2000 to 2020, the construction land increased significantly, an increase of 339.265 km², and the area of forest land increased by 96.707 km²; the area of water, cultivated land, grassland and unused land decreased by 13.333 km², 275.037 km², 146.073 km² and 1.223 km², respectively. From 2000 to 2020, the carbon storage in Taiyuan has decreased by 2 312 591.65 t. Different from the natural development scenario, under the ecological protection scenario, the forest land will increase slightly in 2030 compared with 2020, and the construction land will be effectively limited and expanded, both of which facilitated the generation of ecological effects under the ecological protection scenario. In 2030, the carbon storage under the ecological protection scenario is 1 760 959.397 t more than that under the natural development scenario. From the perspective of land use changes, the increase in forest area is the main reason for the increase in carbon storage in the study area, and the carbon sequestration capacity is enhanced under the ecological protection scenario. This study will provide a scientific basis for land use structure adjustment and management in Taiyuan. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the operability and effectiveness of a self-developed patellar bone canal locator (hereinafter referred to as "locator") in the reconstruction of the medial patellofemoral ligament (MPFL)., Methods: A total of 38 patients with recurrent patellar dislocation who met the selection criteria admitted between January 2022 and December 2022 were randomly divided into study group (the patellar canal was established with a locator during MPFL reconstruction) and control group (no locator was used in MPFL reconstruction), with 19 cases in each group. There was no significant difference in baseline data between the two groups ( P >0.05), such as gender, age, body mass index, disease duration, patella Wiberg classification, constituent ratio of cartilage injury, Caton index, tibia tubercle-trochlear groove, and preoperative Lysholm score, Kujal score, Tegner score, visual analogue scale (VAS) score, and so on. The Lysholm score, Kujal score, Tegner score, and VAS score were used to evaluate knee joint function before operation and at 3 days,1 month, 3 months, and 6 months after operation. The ideal prepatellar cortical thickness and canal length were measured before operation, and the actual prepatellar cortical thickness and canal length after operation were also measured, and D1 (the distance between the ideal entrance and the actual entrance), D2 (the ideal canal length minus the actual canal length), D3 (the ideal prepatellar cortical thickness minus the actual prepatellar cortical thickness) were calculated., Results: Patients in both groups were followed up 6-8 months (mean, 6.7 months). The incision length and intraoperative blood loss in the study group were smaller than those in the control group, but the operation time was longer than that in the control group, the differences were significant ( P <0.05). There was no complication such as incision infection, effusion, and delayed healing in both groups, and no further dislocation occurred during follow-up. One patient in the study group had persistent pain in the anserine area after operation, and the symptoms were relieved after physiotherapy. The VAS score of the two groups increased significantly at 3 days after operation, and gradually decreased with the extension of time; the change trends of Lysholm score, Kujal score, and Tegner score were opposite to VAS score. Except that the Lysholm score and Kujal score of the study group were higher than those of the control group at 3 days after operation, and the VAS score of the study group was lower than that of the control group at 3 days and 1 month after operation, the differences were significant ( P <0.05), there was no significant difference in the scores between the two groups at other time points ( P >0.05). Patellar bone canal evaluation showed that there was no significant difference in preoperative simulated ideal canal length, prepatellar cortical thickness, and postoperative actual canal length between the two groups ( P >0.05). The postoperative actual prepatellar cortical thickness of the study group was significantly smaller than that of the control group ( P <0.05). D1 and D3 in the study group were significantly higher than those in control group ( P <0.05), but there was no significant difference in D2 between the two groups ( P >0.05)., Conclusion: The locator can improve the accuracy of MPFL reconstruction surgery, reduce the possibility of intraoperative damage to the articular surface of patella and postoperative patellar fractures.

Objective: To investigate the epidemiological and clinical characteristics of patients with thoracolumbar osteoporotic vertebral compression fracture (OVCF) treated by percutaneous vertebroplasty (PVP)., Methods: The clinical and imaging data of 681 patients with thoracolumbar OVCF treated with PVP between January 2017 and December 2021 were collected. The epidemiological and clinical characteristics of the patients with thoracolumbar OVCF in single center were summarized from the aspects of demographic distribution (mainly including gender, age), fracture characteristic analysis [including pathological segments, bone mineral density, and body mass index (BMI)], and operation related results (including the distribution of unilateral and bilateral puncture and bone cement injection, postoperative effectiveness analysis and refracture)., Results: Of the 681 patients, 134 (19.68%) were male and 547 (80.32%) were female, with a male-to-female ratio of 1∶4.08. The age ranged from 53 to 105 years, with an average of 75.3 years. The age group of 60-90 years old had the largest number of patients (91.04%); the high incidence age group of men was 70-90 years old (13.95%), and that of women was 60-80 years old (72.98%). A total of 836 vertebrae were involved, and the morbidity of thoracolumbar vertebrae (T 11 -L 1 ) was the highest (56.34%, 471/836). The main type of fracture was compression fracture (92.58%, 774/836) and Kümmell disease (7.42%, 62/836). There were 489 cases (71.81%) of osteoporosis, including 66 males and 423 females, with a male-to-female ratio of 1∶6.42. There was significant difference in distribution of bone mineral density between male and female groups ( Z =-5.810, P <0.001). BMI showed 206 cases (30.25%) of underweight, 347 (50.95%) cases of normal, 58 cases (8.52%) of overweight, 42 cases (6.17%) of obese, and 28 cases (4.11%) of extremely obese. The difference in BMI distribution between male and female groups was significant ( Z =-2.220, P =0.026). Of 836 vertebral bodies, 472 (56.46%) were punctured unilaterally and 364 (43.54%) bilaterally. Most of the vertebral bodies (49.88%, 417/836) were injected with 5.0-6.9 mL bone cement, and most of them were distributed in thoracolumbar and lumbar vertebral bodies (T 11 -L 3 ). The visual analogue scale (VAS) score and Oswestry disability index (ODI) of patients with unilateral puncture and bilateral puncture significantly improved at 6 months after operation ( P <0.001), and also the difference was significant between the two groups in the difference of pre- and post-operation ( P< 0.001). There were 628 cases (92.22%) with the first occurrence of OVCF, and 53 cases (7.78%) with two or more times of OVCF, all of which were female patients, and 26 cases (49.06%) occurred in the adjacent segment of the previous PVP operation., Conclusion: Female were more than male in OVCF patients. Thoracolumbar vertebral body has the highest morbidity. Patients with low BMI are more likely to have osteoporosis, and patients with high BMI have a higher risk of compression fracture. The amount of bone cement injected through bilateral puncture was greater than that through unilateral puncture.

As a degenerative joint disease, osteoarthritis (OA) constitutes a major cause of disability that seriously affects the quality of life of a large population of people worldwide. However, effective treatment that can successfully reverse OA progression is lacking until now. The present study aimed to determine whether two small non-coding RNAs miR-29a and miR-140, which are significantly down-regulated in OA, can be applied together as potential therapeutic targets for OA treatment. MiRNA synergy score was used to screen the miRNA pairs that potentially synergistically regulate OA. An in vitro model of OA was established by treating murine chondrocytes with IL-1β. Transfection of miR-29a and miR-140 via plasmids was investigated on chondrocyte proliferation and expression of nine genes such as ADAMTS4, ADAMTS5, ACAN, COL2A1, COL10A1, MMP1, MMP3, MMP13 and TIMP metal-lopeptidase inhibitor 1 (TIMP1). Western blotting was used to determine the protein expression level of MMP13 and TIMP1, and ELISA was used to detect the content of type II collagen. Combined use of miR-29a and miR-140 successfully reversed the destructive effect of IL-1β on chondrocyte proliferation, and notably affected the MMP13 and TIMP1 gene expression that regulates extracellular matrix. Although co-transfection of miR-29a and miR-140 did not show a synergistic effect on MMP13 protein expression and type II collagen release, but both of them can significantly suppress the protein abundance of MMP13 and restore the type II collagen release in IL-1β treated chondrocytes. Compared with single miRNA transfection, cotransfection of both miRNAs exceedingly abrogated the suppressed the protein production of TIMP1 caused by IL-1β, thereby suggesting potent synergistic action. These results provided novel insights into the important function of miRNAs' collaboration in OA pathological development. The reduced MMP13, and enhanced TIMP1 protein production and type II collagen release also implies that miR-29a and miR-140 combination treatment may be a possible treatment for OA.