New insight into the spatiotemporal distribution and ecological risk assessment of endocrine-disrupting chemicals in the Minjiang and Tuojiang rivers: perspective of watershed landscape patterns.

This study evaluated the pollution characteristics, spatiotemporal distribution, and ecological risks of eight endocrine-disrupting chemicals (EDCs) in the Minjiang and Tuojiang rivers. Utilizing 3S technology (ArcGIS, remote sensing, GPS) and Fragstats, the research calculated eight landscape pattern indices related to land use types along the Minjiang river and established correlations between landscape factors and EDC distribution through stepwise multiple regression. The results indicated that bisphenol A (BPA) and nonylphenol (NP) were the most concerning EDCs, with detection frequencies of 97-100% and peak concentrations up to 63.35 ng L-1, primarily located in the middle and lower reaches of the Minjiang river and the upper reaches of the Tuojiang river. There was a significant correlation between the spatial distribution of pollutants and landscape patterns, where increased fragmentation, a higher number of patches, and complex patch shapes within a 10-kilometer buffer zone were associated with elevated levels of river pollution. By integrating four classical mathematical models to fit curves for acute and chronic toxicity data of BPA and NP, the findings suggested that BPA posed a higher ecological risk. This interdisciplinary research provided essential theoretical insights for investigating river pollution and its influencing factors, offering a new perspective on simultaneous river pollution control, urban functional zoning, and adjustment of watershed landscape spatial patterns from an urban planning standpoint.

Polarization-insensitive multimode interference coupler based on a subwavelength grating structure.

A multimode interference (MMI) coupler is one of the basic components for photonic integrated circuits. However, MMI couplers realized by conventional waveguides are polarization sensitive, which is undesired for many applications, such as optical switches and communications. In this Letter, we propose a polarization-insensitive MMI coupler on a 220-nm silicon-on-insulator platform by constructing different effective interference lengths for TE and TM modes assisted with subwavelength grating structures. The designed MMI coupler shows an excess loss of <0.24(0.43) dB and a power imbalance of <0.6(0.5) dB for the TE(TM) mode over the wavelength range of 1.5-1.6 µm in theory. Experimentally, the fabricated MMI exhibits low excess loss <0.64(0.53) dB and power imbalance <1(0.85) dB for the TE(TM) mode over a wavelength range of 1.55-1.61 µm.

Fabrication of magnetic MnFe2O4@HL composites with an in situ Fenton-like reaction for enhancing tetracycline degradation.

Novel magnetic MnFe2O4@honey locust-derived carbon (MnFe2O4@HL) composites were synthesized via an in-situ hydrothermal precipitation method, and were characterized as an excellent Fenton-like catalyst for tetracycline (TC) degradation. Results showed that the vast majority of TC was mineralized in hydrogen peroxide (H2O2)/MnFe2O4@HL system after 120 min of reaction time with 92.3% of removal efficiency and the removal of 71.3% of total organic carbon (TOC). Systematic characterization approaches including scanning electron microscope (SEM), energy-dispersive X-ray spectrometry (EDS), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and vibrating sample magnetometry (VSM) were introduced to reveal the microstructure and properties of magnetic MnFe2O4@HL composites. Hydroxyl radicals (•OH) were identified as the major reactive oxygen species (ROS) via the quenching experiments and electron spin resonance (ESR) analysis, while superoxide radicals (·O2-) played a negligible role. The dual cycles of both Fe3+/Fe2+ and Mn3+/Mn2+ were significant enhanced through the bimetallic redox effect and the electron transfer effect of the carbon-based functional group, accelerating the generation of •OH. The removal of TC was still up to 79.3% after five reuses of magnetic composites, demonstrating the MnFe2O4@HL with excellent stability and reuse performance. The influence of various experimental control conditions involving initial pH, catalyst and H2O2 dosage, temperature, as well as common anions (Cl-, NO3-, and HCO3-) on the degradation of TC were finally evaluated. This study provides an efficient in-situ generation method of emerging magnetic materials, and systematically reveals its mechanism of homogeneous Fenton-like catalysis, which shows promising applications for the degradation of environmental contaminants.

Ecological remediation strategy for urban brownfield renewal in Sichuan Province, China: a health risk evaluation perspective.

Urban brownfield sites are abandoned industrial land and their redevelopment may be affected by environmental pollution, as the latter may pose health risks for residents. In this study, six heavy metals (Pb, As, Cr, Zn, Ni, and Cu) were examined from 87 soil samples extracted from four land use types (industrial area, residential/commercial area, traffic area, and agricultural area) in the Mianyang thermal power plant area, Sichuan Province, China. The soil contamination and environmental risk were evaluated using the single factor index, geo-accumulation index and Human Health Risk Evaluation. ArcGIS was used to map out the spatial distribution of heavy metal concentrations and environmental risk. The results of these analyses have indicated that different land use types have significant effects on the heavy metal contamination of soil. There are 10 non-carcinogenic risk areas of heavy metals in industrial land, while in the other three types there are 9 non-carcinogenic risk areas of heavy metals. Under the brownfield renewal planning, the present study scheme provides an effective method of discernment for ecological remediation of soil heavy metals. In addition, it can aid brownfield in finding different remediation strategies with economic benefits for different risk levels of human health.

Developing and validating the transition status scale for newly graduated nurses in China.

AIM: The present study aimed to develop and examine the psychometric properties of the Transition Status Scale for Newly Graduated Nurses. METHODS: Three phases were conducted: Phase I involved a qualitative research to explore and establish the potential items pool; Phase II reduced the items using the item analysis with a sample of 73 nurses. Phase III evaluated the psychometric properties of the final scale. Data from 814 valid questionnaires were analysed using exploratory factor analysis and confirmatory factor analysis. RESULTS: Five factors, including 'Interpersonal integration', 'Profession-related positive emotion', 'Competence for nursing work', and 'Active coping strategies', 'Balance between work and life', accounted for 68.87% of total variance. Cronbach's α was 0.891. Confirmatory factor analysis indicated acceptable model fitness. CONCLUSIONS: The Transition Status Scale for Newly Graduated Nurses has good psychometric properties. It can be used to measure the transition status conveniently and effectively. IMPLICATIONS FOR NURSING MANAGEMENT: The assessment result with the Transition Status Scale for Newly Graduated Nurses can provide information about the transition status of new nurses, thereby providing reference to guide the specific nursing interventions to smooth the transition process. It can also work as an alternative instrument to compare the effectiveness of different transition programs.