摘要 : Water is a prerequisite for the formation of earth-biochemical-ecological systems. Differences in the spatial and temporal distribution of water resources are important factors in the formation of differences in the distribution of vegetation in terrestrial ecosystems and are key to the differences in vegetation productivity. Vegetation water use efficiency is calculated by the total amount of fixed biogenic carbon per unit mass of water consumed in photosynthesis and can be used to assess the intensity and capacity of an ecosystem to use water biomass. Based on remote satellite sensing data, this study proposes a new water use efficiency assessment model. The model was validated using flux site data, and we analyzed the relative contribution of climate factors to soil moisture use efficiency using a first-difference method. The results revealed the following: (1) The soil moisture use efficiencies (SUE) of remote sensing data inversions that were evaluated using flux site data based on correlation coefficients and Nash coefficients showed high reliability, and only the NMG (Inner Mongolia) station showed low correlation among the nine sites. (2) Among the nine agricultural sub-regions in China, only the SUE of the Qinghai-Tibet Plateau region showed a decreasing trend (−1.08 g C/m−2 kg H2O yr), while all other regions showed an increasing trend. (3) The highest vegetation soil moisture use efficiency (1.83 g C/m−2 kg H2O) was found in ferralisols, while the lowest vegetation SUE (0.17 g C/m−2 kg H2O) was found in arid soils. The SUE of different vegetation types showed the characteristics of forest > scrub > cultivated vegetation > wetland > grassland. (4) The relative contribution of gross primary productivity (GPP) to the change in SUE was 37.53%, while the relative contribution of soil moisture content to the change in SUE was −26.71%. Among the five climatic factors, temperature was the most dominant factor affecting the change in SUE, followed by precipitation, net radiation, leaf area index, and potential evapotranspiration. Revealing the relationship between terrestrial ecosystem GPP, soil moisture content, and their responses to climate factors is a prerequisite for understanding the adaptation strategies of regional terrestrial ecosystems to global climate change, which can help to inform decision-making for the sustainable development of ecosystems. © 2023

摘要 : In situ-forming hydrogels are highly effective in covering complex and irregular tissue defects. Herein, a biomimetic gel implant (CS-GEL) consisting of methacrylated chondroitin sulfate and gelatin is obtained via visible light irradiation, which displays rapid gelation (∼30 s), suitable mechanical properties, and biological features to support osteoblast attachment and proliferation. Sclerostin is proven to be a viable target to promote osteogenesis. Hence, baicalin, a natural flavonoid with a high affinity to sclerostin, is selected as the therapeutic compound to achieve localized neutralization of sclerostin. To overcome its poor solubility and permeability, a baicalin nanocomplex (BNP) is synthesized using Solutol HS15, which is then dispersed in the CS-GEL to afford a nanocomposite delivery system, i.e., BNP-loaded gel (BNP@CS-GEL). In vitro, BNP significantly downregulated the level of sclerostin in MLO-Y4 osteocytes. In vivo, either CS-GEL or BNP@CS-GEL is proven to effectively promote osteogenesis and angiogenesis in a calvarial critical-sized bone defect rat model, with BNP@CS-GEL showing the best pro-healing effect. Specifically, the BNP@CS-GEL-treated group significantly downregulated the sclerostin level as compared to the sham group (p < 0.05). RANKL expression was also significantly suppressed by BNP in MLO-Y4 cells and BNP@CS-GEL in vivo. Collectively, our study offers a facile and viable gel platform in combination with nanoparticulated baicalin for the localized neutralization of sclerostin to promote bone regeneration and repair.

摘要 : Because of their simplicity, rapidity, and cost-effectiveness, immunochromatographic strips (ICTs) have been widely used as an effective tool in various fields. However, typical strips for the preliminary screening suffer from limited detection sensitivity, particularly in biomarker detection with trace concentration. Herein, to tackle this challenge, we integrated homemade gold-decorated Fe3O4 nanoparticles (Au/Fe3O4 NPs) with flexible strips, exploring the excellent peroxidase-like activity of this labeled material, and then enhancing the detection sensitivity via signal amplification. The limit of detection (LOD) of the strips is as low as 0.05 mIU mL−1 when human chorionic gonadotropin (hCG) is as a biomarker model, which is 500 times lower than that of the traditional color-based strip. Overall, our results demonstrated the potential for Au/Fe3O4 NP based-ICTs for the rapid detection of the biomarker in an instrument-free and point-of-care testing format.

摘要 : High-temperature self-lubricating Fe-Mo-Ni-Cu-graphite materials with varying copper contents were prepared by powder metallurgy technology. The microstructure and wear surface of the sintered alloy were observed and analyzed using optical microscopy and scanning electron microscopy. The focus was on discussion of the influence of copper content on the tribological properties of the iron-based material. The results indicate that the friction coefficient and wear rate of the sintered material against a 40Cr steel disc show a decreasing trend after friction with an increase in copper content. Particularly, at a copper content of 15%, the friction coefficient is lowest at both room temperature and 500 degrees C, exhibiting the best wear resistance. The wear rate is in the order of 10-7 cm3/N center dot m, indicating mild wear. The predominant wear mechanism for both the material and the counterpart disc is adhesive wear. During friction, the formation of a black-brown lubricating composite film composed of Fe2O3, graphite, Fe2O3 center dot Fe3O4, CuO, and Fe3O4 on the material's surface plays a crucial role in providing excellent high-temperature anti-friction properties.

摘要 : Nanopore sensing is highly promising in single molecular analysis but their broad applications have been challenged by the limited strategies that can transduce a target-of-interest into a specific and anti-false/inference signal, especially for solid-state nanopores with relatively lower resolution and higher noise. Here we report a high-resolution signal-production concept named target-induced duplex polymerization strategy (DPS). Through linking the same or different duplex substrates (DSs) with a special linker (L) and an optional structure tag (ST), the DPS can generate target-specific DS polymers with highly controllable duration times, duration intervals and even distinguished secondary tagging currents. Experimentally, DPS mono-polymerization of single DS and co-polymerization of multiple DSs has verified the duration time of a DPS product is the sum of those for each DS monomer. Tetrahedron-DNA structures with different sizes are used as the STs to provide needle-like secondary peaks for further resolution enhancement and multiplex assay. With these examples DPS represents a general, programmable and advanced strategy that may simultaneously provide size-amplification, concentration amplification, and signal-specificity for molecular recognition. It is also promisingly in various applications regarding to single molecular investigation, such as polymerization degree, structure/side chain conformation, programmable multiplex decoding and information index. © 2023 Wiley-VCH GmbH.

摘要 : Integrated with the Allegro promotion of chrome-free organic tanning systems, multifunctional amphoteric wet-finishing materials show great promise for settling current issues such as low chemical absorption rates and cumbersome processes. Herein, we developed a disruptive "three-in-one" strategy based on an on-demand multifunctional fluorescent amphoteric polymer (referred to as pADD-DMENA). As expected, pADD-DMENA exhibited satisfactorily integrated "three-in-one" origins including retanning, fatliquoring and dyeing properties. Compared to conventional anionic dyed leather, pADD-DMENA dyed leather had a uniformly bright yellow color surface and superior lightfastness, durability, and washability. Furthermore, its fluorescence ontology enabled the visual tracking of pADD-DMENA in crust leather and sewage, allowing for real-time monitoring of pADD-DMENA's precise distribution. To summarize, the development of pADD-DMENA allows the traditional wet finishing process to be completed in one step, effectively saving the process time, reducing the additives of various chemicals by 11.2%, and demonstrating better degradability of wastewater (0.35 of BOD5/COD). This novel strategy broadens the route to ecological leather manufacturing in a green direction with low energy consumption and less pollution.

摘要 : The growth of solid tumors is inevitably accompanied by hypoxia and angiogenesis. Understanding the true state of tissue hypoxia and angiogenesis during tumor progression will help further comprehend the tumor microenvironment and cancer therapy. Here, we provided a novel strategy for the long-term tracking of tumor hypoxia and angiogenesis in cervical cancer. The hypoxia response elements (HRE)-driven luciferase (LUC) reporter gene transfected cervical cancer cell lines were constructed for hypoxia visualization. The hypoxia response activity of HRE-driven LUC was verified in HeLa cells and then monitored via the HeLa-HRE-LUC tumor-bearing mouse models by bioluminescence imaging (BLI). An oxygen-sensitive nanoparticle was constructed for glycerol monooleate cubic liquid crystal material loaded with Ir(piq)3/IR780 and could be used for phosphorescence-fluorescence imaging. The imaging result showed that the nanoparticles labeled the low oxygen region overlapped with the BLI signal region detected by HRE-driven LUC in vivo, which confirmed that the hypoxia visualization platform could genuinely reflect the hypoxia level in vivo. The angiogenesis in vivo was reflected by changes in deoxygenated/oxygenated hemoglobin detected by photoacoustic imaging. Besides these, anticancer drug apigenin down-regulated HIF-1α and VEGF under hypoxia conditions and inhibited the tube formation in vitro. Then, the inhibition effects were verified in the hypoxia and angiogenesis visualization model in vivo. This study confirmed a novel in vivo real-time monitoring of tumor hypoxia and angiogenesis strategy, which can provide useful information for further research on cancer progression and anticancer therapy. © 2023 Elsevier B.V.

摘要 : In this study, a facile method has been developed to synthesize a novel type of porous magnetic molecularly imprinted polymers (Fe3O4-MER-MMIPs) for the selective adsorption and removal of meropenem. The Fe3O4-MER-MMIPs, with abundant functional groups and sufficient magnetism for easy separation, are prepared in aqueous solutions. The porous carriers reduce the overall mass of the MMIPs, greatly improving their adsorption capacity per unit mass and optimizing the overall value of the adsorbents. The green preparation conditions, adsorption performance, and physical and chemical properties of Fe3O4-MER-MMIPs have been carefully studied. The developed submicron materials exhibit a homogeneous morphology, satisfactory superparamagnetism (60 emu g-1), large adsorption capacity (11.49 mg g-1), quick adsorption kinetics (40 min), and good practical implementation in human serum and environmental water. Finally, the protocol developed in this work delivers a green and feasible method for synthesizing highly efficient adsorbents for the specific adsorption and removal of other antibiotics as well.

摘要 : Virus-like particles (VLPs) are viral structural protein that are noninfectious as they do not contain viral genetic materials. They are safe and effective immune stimulators and play important roles in vaccine development because of their intrinsic immunogenicity to induce cellular and humoral immune responses. In the design of antiviral vaccine, VLPs based vaccines are appealing multifunctional candidates with the advantages such as self-assembling nanoscaled structures, repetitive surface epitopes, ease of genetic and chemical modifications, versatility as antigen presenting platforms, intrinsic immunogenicity, higher safety profile in comparison with live-attenuated vaccines and inactivated vaccines. In this review, we discuss the mechanism of VLPs vaccine inducing cellular and humoral immune responses. We outline the impact of size, shape, surface charge, antigen presentation, genetic and chemical modification, and expression systems when constructing effective VLPs based vaccines. Recent applications of antiviral VLPs vaccines and their clinical trials are summarized.

摘要 : Microorganism is an important part of geochemical cycle and plays an irreplaceable role in ecosystem. Optimization of microbial assay is very important. In this paper, genetic algorithm is used to optimize the microbial test. Using the operating mechanism of genetic algorithm, that is, imitating the basic laws of nature, carrying out natural selection and survival of the fittest, using this principle to treat the detection of microbial detection optimization. Through the natural selection and survival of the fittest, genetic algorithm weight adjustment, so as to achieve more accuracy of the test. By referring to the mathematical formulas (1) and (2) in Part 3 of this paper, the requirements of determining the definition of microbial detection can be achieved by initializing the population of microorganisms and analyzing the global convergence of the samples that meet the standards and do not meet the standards. This paper studies the knowledge of microbial test optimization system based on genetic algorithm, and describes the methods and principles of microbial test. The results show that the optimization effect of microbial test is improved significantly by the optimization system based on genetic algorithm.