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Supervision lies at the heart of research-based doctoral education. Existing scholarship has recognized the role of supervision in students' academic socialization and identity construction but presented little empirical evidence based on prolonged observations of actual supervisory interactions. Addressing this gap, the present study adopted a digital micro-ethnographic approach to examine how a supervisor mediated a doctoral student's academic identity construction in their supervisory interactions. Multiple-sourced data were collected over a two-year span, including the focal participants' interactions through instant messaging, interviews, and artefacts. Informed by a sociocultural view of identity work in social interaction, data were subjected to both thematic analysis and micro-level discourse analysis. The analyses revealed that the supervisor drew upon transformative criticism, strategic recognition, and his own identity to mediate the doctoral student's academic identity construction in an iterative process that often involved rounds of negotiations between different positionings. Situating the supervisor's discursive practice at the macro-sociological level of doctoral education, this study contributes new insights into doctoral supervision as a hybridized and contingent practice that integrates the professional and the personal as well as the hierarchal and the collegial. The study offers important implications for doctoral supervision. [ABSTRACT FROM AUTHOR]

Ecological ditches serve as one of the important measures for the concentrated infiltration of stormwater in the construction process of sponge cities. Prolonged concentrated infiltration of stormwater can lead to the accumulation of pollutants and pollution risks in the substrate of ecological ditches. In this study, two different substrate ecological ditches were constructed, namely, a combined substrate ecological ditch with zeolite + ceramsite (EA), and a biological substrate ecological ditch (EB). The accumulation characteristics of pollutants and microbial mechanisms in the ecological ditches were evaluated by simulating the cumulative rainfall test for three years. Results showed that there was serious total nitrogen (TN) contamination in both EA and EB substrates, with mean values of 718.6 and 802.7 mg/kg, respectively. The average contents of potentially toxic elements (Cu, Pb, and Zn) in EA and EB substrates were higher than the background values of soil elements in China, and Cu posed considerable ecological risks to the environment. Proteobacteria was the dominant phylum and accounted for 32.85–41.33% in two ditches; the total number of denitrifying functional bacterial genera in the EB increased by 1.53% than EA, which proved that the biological substrate was more favourable for the growth of denitrifying microorganisms. The accumulation characteristics of pollutants and microbial mechanisms in the ecological ditches with different substrates above provide a reference for extending the service life of ecological ditch facilities. [ABSTRACT FROM AUTHOR]

The selection of suitable raw materials as adsorbents is a key factor in effectively removing phosphorus from water. As an industrial by-product, soda residue exhibits high porosity and surface area, which can effectively adsorb pollutants. Magnetic lanthanum-iron soda residue (La-Fe-CSR) was synthesized using the co-precipitation method, and its characterization and mechanism for removing phosphate were thoroughly investigated. La-Fe-CSR exhibited good adsorption performance under acidic conditions (3 < pH < 7). A high concentration of HCO3− (100 mg/L) reduced the adsorption performance of La-Fe-CSR by 8.3% ± 2.5%, whereas the presence of other coexisting ions had a smaller impact. The adsorption of phosphate by La-Fe-CSR was controlled by chemisorption and reached saturation after approximately 120 min. The phosphate adsorption by La-Fe-CSR was significantly higher than that of soda residue (43.65 ± 3.39 mg/g), reaching 74.87 ± 2.46 mg/g. Ligand exchange and inner-sphere complexation constituted the primary mechanisms through which L-Fe-CSR removed phosphate. After 5 consecutive cycles, La-Fe-CSR maintained a phosphate removal efficiency of 74.5 ± 1.6%. It demonstrated good performance in removing total phosphorus from real domestic sewage, with a removal rate of 94.9 ± 0.5%. These research findings demonstrated that La-Fe-CSR held significant promise as a highly effective phosphate adsorbent in practical applications. [ABSTRACT FROM AUTHOR]

Multiconfiguration pair-density functional theory (MC-PDFT) was proposed a decade ago, but it is still in the early stage of density functional development. MC-PDFT uses functionals that are called on-top functionals; they depend on the density and the on-top pair density. Most MC-PDFT calculations to date have been unoptimized translations of generalized gradient approximations (GGAs) of Kohn-Sham density functional theory (KS-DFT). A hybrid MC-PDFT has also been developed, in which one includes a fraction of the complete active space self-consistent-field wave function energy in the total energy. Meta-GGA functionals, which use kinetic-energy densities in addition to GGA ingredients, have shown higher accuracy than GGAs in KS-DFT, yet the translation of meta-GGAs has not been previously proposed for MC-PDFT. In this paper, we propose a way to include kinetic energy density in a hybrid on-top functional for MC-PDFT, and we optimize the parameters of the resulting functional by training with a database developed as part of the present work that contains a wide variety of systems with diverse characters. The resulting hybrid meta functional is called the MC23 functional. We find that MC23 has improved performance as compared to KS-DFT functionals for both strongly and weakly correlated systems. We recommend MC23 for future MC-PDFT calculations. [ABSTRACT FROM AUTHOR]

To fulfill the needs of neutron capture reaction cross-section measurement in the keV energy region in the field of nuclear astrophysics and advanced nuclear energy system development, the 4π BaF_2 Gamma-Ray Total Absorption Facility (GTAF) developed by the Key Laboratory of Nuclear Data of the China Institute of Atomic Energy (CIAE) was transplanted and installed at the Back-streaming White Neutron Source (Back-n) of the China Spallation Neutron Source (CSNS) in 2019. A series of results has been achieved and published based on the GTAF since then, and it has been identified that the need of reducing backgrounds is becoming increasingly urgent. In order to understand the origins of backgrounds and to optimize the facilities, a detailed simulation program using GEANT4 toolkits was established and is presented in this paper. The symmetry in the geometric arrangement of the 4π BaF2 detector array plays a critical role in ensuring uniform detection efficiency and accurate reconstruction of gamma-ray spectra, which is essential for neutron capture studies. To demonstrate the availability of the proven codes, several practical examples of assisting the process of experimental data and helping verify the optimization proposition are also shown in this paper. [ABSTRACT FROM AUTHOR]

Chronic kidney disease (CKD) stands as a formidable global health challenge, often advancing to end-stage renal disease (ESRD) with devastating morbidity and mortality. At the central of this progression lies podocyte injury, a critical determinant of glomerular dysfunction. Compound K (CK), a bioactive metabolite derived from ginsenoside, has emerged as a compelling candidate for nephroprotective therapy. Here, we unveil the profound therapeutic potential of CK in a folic acid (FA)-induced CKD mouse model, demonstrating its ability to restore renal function and mitigate podocyte injury. CK exerted its nephroprotective effects by reinforcing inter-podocyte junctions, suppressing aberrant podocyte motility, and preventing podocyte detachment and apoptosis, thereby safeguarding the glomerular filtration barrier. Mechanistically, we identified mitochondrial dysregulation as a key driver of excessive oxidative stress, which is commonly associated with podocyte damage. CK remarkably restored mitochondrial homeostasis by attenuating pathological mitochondrial fission and enhancing mitophagy, thereby rebalancing the delicate mitochondrial network. Intriguingly, CK may disrupt the formation of the Drp1-Bax dimer, a crucial mediator of mitochondrial apoptosis, further averting podocyte loss. Collectively, our findings highlight CK as a potent nephroprotective agent, offering a novel therapeutic avenue for CKD management and redefining possibilities in the battle against progressive renal disease. [ABSTRACT FROM AUTHOR]