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In this work, we have fabricated a surface-enhanced Raman scattering (SERS) magnetic immunosensor using a sandwich structure consisting of an SERS tag, a supporting substrate with magnetic properties, and a target. On the one hand, the SERS tag consists of AgNPs, a metal–organic framework called the zeolite imidazolate framework-67 (ZIF-67), and R6G, which acts as a Raman reporter. Due to the self-selective SERS-enhancing properties of ZIF-67 and better adsorption to analytes, SERS tags with this structure can further enhance the sensing capabilities. On the other hand, after surface functionalization with the human carboxylesterase 1 (hCE1) antibody, the nanostructure containing CoFe2O4 as the magnetic core and Ag NPs as the shell was used as the magnetic support substrate. The introduction of the CoFe2O4 magnetic core can not only realize the rapid separation of biological samples to simplify pre-treatment procedures but also stabilize and uniformly distribute the AgNPs and increase the Raman "hot spots", thereby further enhancing the SERS intensity and improving the reproducibility. Not only that, the SERS signal can be further enhanced by the synergistic effect generated by the plasmonic coupling of the CoFe2O4 magnetic core–Ag satellite nanostructure (CoFe2O4/Ag). hCE1 in HepG-2 cell lysates and culture supernatants was rapidly determined using the constructed SERS magnetic immunosensor, and hCE1 released from acetaminophen-treated HepG-2 cells into the extracellular medium was also monitored in real time. The limit of detection was as low as 3.6 pg/mL, and the linear response covered a range of hCE1 concentrations (1.0 ng/mL–1.0 mg/mL) spanning 3 orders of magnitude. This strategy can be used for the quantitative detection of complex trace proteins or enzymes in biological samples. [ABSTRACT FROM AUTHOR]

Mass spectrometry imaging (MSI) is a powerful label‐free analysis technique that can provide simultaneous spatial distribution of multiple compounds in a single experiment. By combining the sensitive and rapid screening of high‐throughput MS with spatial chemical information, metabolite analysis and morphological characteristics are presented in a single image. MSI can be used for qualitative and quantitative analysis of metabolic profiles and it can provide visual analysis of spatial distribution information of complex biological and microbial systems. Matrix‐assisted laser desorption ionization, laser ablation electrospray ionization and desorption electrospray ionization are commonly used in MSI. Here, we summarize and compare these three technologies, as well as the applications and prospects of MSI in metabolomics. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectric capacitors receive extensive attention for the energy storage applications due to their slim polarization–electric field hysteresis loops. Typically, relaxor ferroelectrics can be designed through introducing multiple heterovalent cations in the ferroelectrics to break the long-range ferroelectric order and form polar nanoregion. Here, medium-entropy relaxor ferroelectric (Bi0.7Na0.67Li0.03)0.5Sr0.3TiO3 (BNLST) thin films with A-site chemical heterogeneity, synthesized by a chemical solution method, are studied as dielectric capacitors for the energy storage application. Mn doping is utilized to occupy cation vacancies to improve the electrical properties. High energy density (47 J cm−3), good efficiency (69%), and good frequency, temperature and fatigue stability are obtained simultaneously. These results show the potential applications of SBNLT relaxor ferroelectric thin film for dielectric energy storage. [ABSTRACT FROM AUTHOR]

Leaf Area Index (LAI) is one of the most important biophysical parameters of vegetation, and its dynamic changes can be used as a reflective indicator and differentiation basis of vegetation function. In this study, a VCA–MLC (Vertex Component Analysis–Maximum Likelihood Classification) algorithm is proposed from the perspective of multi-temporal satellite LAI image classification to monitor and quantify the spatial and temporal variability of vegetation dynamics in China since 2000. The algorithm extracts the vegetation endmembers from 46 multi-temporal images of MODIS LAI in 2011 without the aid of other a priori knowledge and uses the maximum likelihood classification method to select the categories that satisfy the requirements of the number of missing periods, absolute distance, and relative distance for the rest pixels to be classified, ultimately dividing the vegetation area of China into 10 vegetation zones called China Vegetation Functional Zones (CVFZ). CVFZ outperforms MCD12Q1 and CLCD land cover datasets in the overall differentiation of vegetation functions and can be used synergistically with other land cover datasets. In this study, CVFZ is used to cut the constant vegetation-type pixels of MCD12Q1 during 2001–2022. The results of the LAI mean time series decomposition of each subregion using the STL (Seasonal-Trend Decomposition based on Loess) method show that the rate of vegetation greening ranges from 9.02 × 10−4 m2m−2yr−1 in shrubland subregions to 2.34 × 10−2 m2m−2yr−1 in savanna subregions. In relative terms, the average greening speed of forests is moderate, and savannas tend to have the fastest average greening speed. The greening speed of grasslands and croplands in different zones varies widely. In contrast, the average greening speed of shrublands is the slowest. In addition, CVFZ detected grasslands with one or two phenological cycles, broadleaf croplands with one or two phenological cycles, and shrublands with no apparent or one phenological cycle. [ABSTRACT FROM AUTHOR]

The outbreak of COVID-19 has engendered extensive challenges for conventional hospital operations. To adapt to this problematic issue, a mixed-use hospital functioning system for normal and epidemic situations is proposed. However, the inherent complexity of a hospital embedded with a function of epidemic prevention and control renders a restrained construction process that may compromise quality. In this stance, we developed a BIM (building information modelling)-based simulation approach addressing life-cycle quality control in post-pandemic hospitals. An illustrative case study approach, which draws on the grey literature, was used to address the research question. BIM forward design was employed to integrate with such elements as functional streamline, emergency site, and ward conversion in the process of transformation from normal to epidemic-related operations. Computational fluid dynamics-based fluid simulation was conducted to obtain the most suitable air supply and exhaust solutions for negative pressure wards. BIM forward design method contributed to improving design efficiency and quality. The results of ventilation simulation and environmental analysis showed that the design scheme met all the functional requirements and technical specifications. Meanwhile, the best pipeline synthesis scheme was obtained, which reduced the rework and saved on construction time. The proposed method is beneficial to improve the efficiency of design information sharing and business collaboration. Implications generated from this study can be used as a significant reference for the future construction of various healthcare facilities. [ABSTRACT FROM AUTHOR]