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Stable isotope techniques have become a critical tool for tracking mine water and identifying its contamination. In order to explore in depth the research hotspots and trends in stable isotope technology in the study of mine water and the environmental pollution it induces, the Web of Science Core Collection (WoSCC) database of the relevant literature in this field from 1998 to 2023 was used for visual bibliometric analysis by applying CiteSpace software (version 5.7R5). The results showed that the periodical literature in this field shows a fluctuating upward trend. In the cooperation network of country and institution, the centrality of the United States was as high as 0.74 and 0.23, much higher than that of other countries, which means that in terms of the institutions, the number of publications, and the status of research, the United States is ahead of other countries. China's research started later than the United States's but is developing rapidly. Although its importance and influence in this research field are only slightly lower than those of the United States, China still needs to improve its cooperation with other countries and regions. The research hotspots in this area center around identifying and understanding pollution processes, studying mine water sources and mixing, exploring the evolution of water chemistry and its isotopic composition, and investigating the environmental impacts of mine water. Innovative isotope-tracing methods and techniques, isotope fractionation mechanisms, sources of sulfate, and their impact on the water environment will remain the focus of the forthcoming research phase. This study uses bibliometrics to systematically summarize the research hotspots and trends in stable isotope techniques in mine water problems in terms of their footprint in the academic literature, which is of great significance for the utilization of water resources in mine drainage and pollution control in mines. [ABSTRACT FROM AUTHOR]

Excessive reactive oxygen species (ROS) generated during cerebral ischemic reperfusion (CIRI) are crucial for subsequent tissue damage. However, despite the potential benefits of antioxidants reported in clinical applications, few have proven effective in treating CIRI, particularly in the elderly. Epicatechin (EC) is a catechol flavonoid monomer derived from natural tea plants. Multiple phenolic hydroxyl groups give it strong antioxidant properties, which can not only degrade ROS through chemical reactions between hydroxyl and ROS but also enhance the activity of antioxidant enzymes in cells, and it is easy to penetrate the blood–brain barrier. But its antagonistic effect on age‐related CIRI and potential medicinal value are still unknown. Nuclear factor erythroid 2‐related factor 2 (Nrf2) is the most important transcription factor regulating the expression of antioxidant proteins in the body. This study first compared the pathological differences of the Nrf2 system in CIRI between 2‐month‐old and 12‐month‐old Sprague–Dawley (SD) rats. Subsequently, EC was administered to 12‐month‐old rat models of middle cerebral artery occlusion and reperfusion (MCAO/R) and senescent SH‐SY5Y cell models subjected to oxygen glucose deprivation/reoxygenation (OGD/R). EC treatment improved cerebral morphology and function; increased p‐Nrf2, heme oxygenase‐1 (HO‐1), superoxide dismutase (SOD), and glutathione (GSH) expression; reduced infarct volume; and neuronal apoptosis in senescent rats. Moreover, EC enhanced cellular activity and the expression of p‐Nrf2, HO‐1, and quinone oxidoreductase‐1 (NQO‐1) while decreasing ROS and malondialdehyde (MDA) levels and mitigating apoptosis in senescent SH‐SY5Y cells. These effects were reversed upon si‐Nrf2. In sum, we confirm that EC exerts neuroprotective effects by upregulating Nrf2/ARE and reducing oxidative stress, suggesting that EC may be a promising drug for the treatment of senile cerebral apoplexy. This study also provides a scientific basis for the development and selection of new drugs for ischemic stroke in elderly patients. [ABSTRACT FROM AUTHOR]

Magnetic nanomaterials (MNPs) have been widely used in the detection of pollutants in the environment because of their excellent nano effect and magnetic properties. These intrinsic properties of MNPs have diversified their application in environmental contaminant detection. In this paper, the research status quo of the use of MNPs in detecting organic and inorganic contaminants from wastewater and soil is reviewed. The preparation method and modification technology of magnetic nanoparticles are also described in detail. The application prospect of magnetic nanoparticle composites in the detection of contaminants in water and soil is discussed. Compared with traditional detection methods, MNPs are more accurate and efficient in pollutant enrichment. Moreover, the biological synthesis of MNPs was proven to be eco-friendly and aided in sustainable development. The study shows that MNPs have good application prospects in soil pollution detection, but the mechanism still needs to be investigated to realize their popularization and application. [ABSTRACT FROM AUTHOR]

W-5% (mass fraction) Re composite powder was fabricated by a new cladding method. W-5%Re nozzles used for solid rocket motor (SRM) were produced by shrouded plasma spray forming (PSF). The change regularity with the sintering time for the compact density, structure, micro-hardness, tensile strength and compression strength of the nozzel under 2300 ℃ vacuum sintering was studied. The study result indicates that the lamellae structure, and vertical columnar grains, micron-sized pores and rough interlamellar contacts with gaps of sub-micron sizes between lamellaes are found in PSF deposits. The relative density, micro-hardness, ultimate tensile strength (UTS) and compressive strength of PSF deposits are 87.5 %, 321.4 HV0.025, 57.9 MPa and 390.2 MPa respectively. With the sintering time prolonged from 2 h to 6 h and 8 h, the relative density and mechanical properties of W-Re alloy parts increase with the initial lamellar structure transformed into granular structure.After vacuum sintering for 8 h, the relative density, micro-hardness, UTS, compressive strength and yield strength increase to 98.6 %, 529.7 HV0.025, 384.7 MPa, 1466.5 MPa and 879.6 MPa respectively. For the addition of Re element, the recrystallization temperature and grain size of W-Re alloy are improved and effectively refined respectively. Thus, the strength and plasticity of the alloy can be improved remarkably, and the Re effect is revalidated and double checked in W-Re alloy fabricated by PSF and Vacuum sintering.

This paper is based on the effect of precursors’ structure on the resultant electropolymers’ electrochemical and optical and thermal properties. The polyacrylate functionalized thiophene with a narrow polydispersity index (PDI) was synthesized by means of reversible addition-fragmentation chain transfer (RAFT) polymerization, and then the free-standing and conducting conjugated polyacrylate functionalized polythiophene (R-PTE-PAA) film was prepared through electropolymerization in CH2Cl2 with 50% BFEE (boron trifluoride diethyl etherate). For comparison, the polyacrylate functionalized polythiophene (PTE-PAA) was also prepared with the precursor of a broad PDI from conventional free radical polymerization. The prepared polymers were characterized by UV-vis, FT-IR spectroscopy, thermogravimetry, cyclic voltammetry, scanning electron microscopy and fluorescence spectrophotometry. The R-PTE-PAA film showed the excellent electrochemical behavior, good blue-light property and high thermal stability. Compared with PTE-PAA, the R-PTE-PAA film presented the better electrochemical reversibility and stability. The results obtained in the present study indicate that the R-PTE-PAA film would be important for applications in electrochromics, supercapacitors and electrochemical sensors.

Background: Anemia is one of the common complications in patients with chronic kidney disease (CKD). However, there is no systematic investigation on the prevalence of anemia in CKD patients and its relationship with the quality of life in China.Methods: The data for this study comes from baseline data from the Chinese Chronic Kidney Disease Cohort Study (C-STRIDE), which recruited predialysis CKD patients in China. The kidney disease quality of life summary (KDQOL-TM) was used to assess health-related quality of life (HRQoL). Use linear regression model to estimate the relationship between hemoglobin level and quality of life.Results: A total of 2921 patients were included in this study. The adjusted prevalence of hemoglobin (Hb) less than 100 g/L was 10.3% (95% confidence interval [CI]: 9.9,11.4%), and showed an increased trend through reduced eGFR levels from 4.0% (95%CI:2.3,5.9%) in the 45-60 ml/min/1.73m2 group to 23.4% (95%CI:20.5,26.2%) in the 15-29 ml/min/1.73m2 group. The prevalence of anti-anemia treatment was 34.0% (95%CI: 28.7,39.3%) and it is shown by reducing eGFR levels from 15.8% (95%CI:0,36.7%) in the 45-60 ml/min/1.73m2 group to 38.2% (95%CI: 30.7,45.2%) in the 15-29 ml/min/1.73m2 group. All five dimensions of the KDQOL scores in patients with CKD decreased as hemoglobin declined. After multivariable adjustments,the degrees of decrease became somewhat blunted. For example, compared with hemoglobin of ≥130 g/L, regression coefficients in the hemoglobin of < 100 g/L were - 0.047(95%CI: - 0.049,-0.045) for Symptoms and Problems(S), - 0.047(95%CI: - 0.049,-0.044) for Effects of the Kidney Disease(E), - 0.207(95%CI: - 0.212,-0.203) for Burden of the Kidney Disease(B), - 0.112(95%CI: - 0.115,-0.109) for SF-12 Physical Functioning (PCS), - 0.295(95%CI: - 0.299, -0.292) for SF-12 Mental Functioning (MCS), respectively.Conclusions: In our cross-sectional analysis of patients with CKD in China, prevalence of both anemia and anti-anemia treatment increased with decreased eGFR. In addition, anemia was associated with reduced HRQoL. [ABSTRACT FROM AUTHOR]

Background: Controversy remains whether white coat hypertension (WCH) is associated with renal prognosis in patients with chronic kidney disease (CKD). Methods: In the present multicenter, prospective study, we analyzed data of participants with CKD stage 1–4 from the Chinese Cohort Study of Chronic Kidney Disease (C-STRIDE). WCH was defined according to two criteria as follows: A, clinical blood pressure (BP) ≥ 140/90 mm Hg and average 24-h ambulatory BP < 130/80 mm Hg; B, clinical BP ≥ 130/80 mm Hg and daytime ambulatory BP < 130/80 mm Hg. Renal outcome was defined as initiation of renal replacement therapy. The association of WCH with renal events was evaluated by Cox regression model. Results: A total of 1714 patients with CKD were included in the present analysis. The mean age of the population was 48.9 ± 13.8 years and 56.8% were men. The mean baseline estimated glomerular filtration rate (eGFR) was 52.2 ± 30.1 ml/min/1.73 m2 and urinary protein was 1.0 (0.4, 2.4) g/day. The overall prevalence of WCH was 4.7% and 16.6% according to criteria A and B, respectively. Incidence rates of renal events were 49.58 and 26.51 according to criteria A and B, respectively, per 1000 person-years during a median follow-up of 4.8 years. After full adjustment, WCH was associated with an increased risk of renal event (criterion A: hazard ratio 2.36, 95% confidence interval 1.29–4.34; for criterion B: hazard ratio 1.90, 95% confidence interval 1.04–3.49) compared with patients with normal BP. Conclusions: WCH is associated with a greater risk for renal events in non-dialysis dependent Chinese patients with CKD. [ABSTRACT FROM AUTHOR]