The relationship between lifestyles and multimorbidity is well established, but previous studies have often neglected the role of spatial heterogeneity. Thus, this study is the first to explore this ...association in Chinese adults from a spatial perspective using a geographically weighted logistic regression (GWLR) model and describe the geographical characteristics across different regions. According to 2018 China Health and Retirement Longitudinal Study (CHARLS) database, a total of 7101 subjects were finally included, with 124 prefecture-level administrative regions in China. Non-spatial and GWLR model were used for analysis, and gender stratification analysis was also performed. Data were visualized through ArcGIS 10.7. The results showed that a total prevalence of approximately 5.13% of multimorbidity, and among participants with multimorbidity, the separate prevalence of hypertension, diabetes or high blood sugar, heart disease, and stroke were 4.45%, 2.32%, 3.02%, and 1.41%, respectively. The GWLR model indicated that current (OR: 1.202-1.220) and former smokers (OR: 1.168-1.206) may be important risk factors for multimorbidity in adults, especially in north and west among male. Past drinkers (OR: 1.233-1.240), especially in eastern China, contribute to the development of the multimorbidity in men but not in women. Vigorous-intensity activities (OR: 0.761-0.799) were negatively associated with multimorbidity in the west, with no gender difference. Depression (OR: 1.266-1.293) appeared to increase the risk for multimorbidity, with the weakest effects in central China and no gender difference. There was an interaction between light activities and gender (P = 0.024). The prevalence of multimorbidity differed across various areas of the province. The role of geographical variations in lifestyles and multimorbidity may provide valuable information for developing site-specific intervention strategies.
Guizhou has many coal seams, thin coal seams, many gangues, and rapid lithology changes. Its complex strata characteristics increase the difficulty of fracturing CBM wells. Taking coalbed methane ...well in Jinjia Coal Mine as an example, we research the risk of complex formation fracturing and fracturing technology, and explore the adaptability of secondary pump-stop fracturing technology under stress disturbance. Engineering practice show that the lithology of coal measures in Jinjia Coal Mine has complex changes, and the lithology can be divided into 5 combination modes; multi-coal and multi-layered coal seams adopt methods such as “avoidance, expansion, selective injection, continuous injection, and directional perforation”, which can reduce the difficulty of fracturing construction. Multi-seam combined layer fracturing and multi-layer coal seam fracturing reform adopted the secondary stop pump fracturing technology, promoted the formation stress redistribution and fracture diversion, and improved the effect
This paper proposes a novel scheme named CodeHop, which provides both information reliability and security using code hopping based on low-density parity-check （LDPC） codes. In contrast to ...traditional systems that perform error correction and encryption at different layers, CodeHop combines these two operations into a single step at physical layer, such that each plaintext message is jointly encoded and encrypted by a hopping parity-check matrix. According to a pseudo-random number generator （PRNG）, the hopping matrix may rapidly switch among a sequence of LDPC parity-check matrices, which is randomly generated by a structured-random protograph expanding technique. Simulations show that reliable communication can be achieved by CodeHop with good error-correcting performance. In the meantime, CodeHop may improve the security of traditional systems such as GSM. Taking the A5/1 stream cipher used in GSM as the PRNG, it is shown that CodeHop is resistant to existing chosen-plaintext attacks that break A5/1 cipher already. Moreover, the security of CodeHop will be enhanced in the presence of channel errors as well.
In the recent years, polyoxometalate (POM) encapsulated metal–organic framework (MOF) composites have attracted much attention in photocatalysis. Both POMs and MOFs have been attracting immense ...attention in this area. Furthermore, in order to promote charge transfer and separation between POMs and MOFs, theoretical and experimental analysis can be applied to match their energy levels; however, their individual applications are hindered by several defects, such as poor visible-light utilization efficiency. The combination of MOFs and POMs can benefit from the virtues of both POMs and MOFs while avoiding the drawbacks of them. Notably, MOFs with high specific surface area and long-range ordered structure ensure a uniform distribution of POMs, which cannot only prevent the self-aggregation of POMs but also allow the exposure of more active sites for catalysis. POM@MOF composites have been identified as promising materials for photocatalysis because of their diverse unique advantages, such as ultrahigh porosity, large specific surface area, and excellent electron redox transformation. In this work, we present an overview of the developments in POM@MOF composite-based catalysts for visible light induced photocatalysis. The strategies employed for the preparation of POM@MOF composites are summarized and discussed with a particular focus on the stability of such materials. The representative works on photocatalytic water splitting, CO2 reduction, degradation of pollutants, and selective oxidation of organics are highlighted. Special attention is paid to the synergistic effects between the MOF and POM that result in an enhanced performance. Besides, the stability and reusability of these materials are also discussed. Also, the unsolved problems and development opportunities of POM@MOF composites in the field of photocatalysis are proposed.
As a newly emerging kind of porous material, covalent organic frameworks (COFs) have drawn much attention because of their fascinating structural features (
e.g.
, divinable structure, adjustable ...porosity and total organic backbone). Since the seminal work of Yaghi and co-workers reported in 2005, the COF materials have shown superior potential in diverse applications, such as gas storage, adsorption, optoelectronics, catalysis,
etc.
Recently, COF materials have shown a new trend in sensing fields. This critical review briefly describes the synthesis routes for COF powders and thin films. What's more, the most fascinating and significant applications of COFs in sensing fields including explosive sensing, humidity sensing, pH detection, biosensing, gas sensing, metal ion sensing, and other substance sensing are summarized and highlighted. Finally, the major challenges and future trends of COFs with respect to their preparation and sensing applications are discussed.
Recent advances in covalent organic frameworks (COFs) as a smart sensing material are summarized and highlighted.
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•Novel S-CQDs/hollow tubular g-C3N4 photocatalyst was successfully fabricated.•HTCN-C(2) exhibited excellent photocatalytic activity for Escherichia coli photodestruction.•The changes ...of Escherichia coli morphology and inside contents were verified by SEM images.•h+, O2− and OH radicals participate in the photocatalytic degradation process.•Cycle experiments revealed the outstanding photo-stability and reusability.
Microbial contamination and antibiotic pollutions diffusely exist in wastewater system, and contaminated water poses a threat to public health. Therefore, there is a need to effectively remove biohazard and antibiotic contamination from wastewater systems. In this paper, sulfur doped carbon quantum dots (S-CQDs)/hollow tubular g-C3N4 photocatalyst (HTCN-C), prepared via ultrasonic assisted synthesis strategy, was regarded as an efficient catalyst for the degradation of antibiotic (tetracycline) and destruction of a typical Gram-negative bacterium (Escherichia coli) in imitated wastewater system. The unique structures of hollow tubular g-C3N4 and loading of modified carbon quantum dots enhanced electron transfer and charge separation, leading to a significant improvement in photocatalytic efficiency. Benefiting from these merits, the optimized catalysts (HTCN-C(2)) exhibited superior performance with a reaction rate of 0.0293 min−1 for tetracycline (TC) degradation and 99.99% destruction of Escherichia coli under visible-light irradiation. Moreover, the characterization of UV–Vis diffuse reflectance spectra, photoluminescence technique, transient photocurrent responses and electrochemical impedance spectroscopy also verified the good optical and electrochemical properties of resultant samples. Our current work indicates that HTCN-C has great potential in degradation of antibiotic and destruction of bacterium for practical wastewater treatment.
► We present a general method to prepare the core–shell magnetic MIPs nanoparticles (Fe3O4@MIPs) for sulfamethazine. ► The Fe3O4@MIPs possess a highly improved imprinting factor, fast adsorption ...kinetics and high adsorption capacity. ► The structure and affinity properties of the resulting Fe3O4@MIPs were characterized. ► We used Fe3O4@MIPs for enrichment and determination of SMZ in the poultry feed samples.
In this study, we present a general method to prepare the core–shell magnetic molecularly imprinted polymers (MIPs) nanoparticles (NPs) for sulfamethazine (SMZ). The resulting Fe3O4@MIPs NPs possess a highly improved imprinting effect, fast adsorption kinetics and high adsorption capacity, and can be applied to extract sulfonamide in the poultry feed. In this protocol, the magnetite NPs were synthesized by co-precipitating Fe2+ and Fe3+ in an ammonia solution first. Silica was then coated on the Fe3O4 NPs using a sol–gel method to obtain silica shell magnetic NPs. Subsequently, the vinyl groups were grated onto silica-modified Fe3O4 surface by 3-methacryloyloxypropyltrimethoxysilane. Finally, the MIPs films were formed on the surface of Fe3O4@SiO2 by the copolymerization of vinyl end groups with functional monomer, methacrylic acid, cross-linking agent, ethylene glycol dimethacrylate, the initiator azo-bis-isobutyronitrile and template molecule, sulfamethazine. The morphology, magnetic, adsorption and recognition properties of Fe3O4@MIPs NPs were characterized using transmission electron microscope (TEM), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectrometer, vibrating sample magnetometer (VSM) and re-binding experiments. The results showed that the binding sites of Fe3O4@MIPs were good accessibility, fast adsorption rate and the maximum adsorption capacity of Fe3O4@MIPs to SMZ was 344.8μgg−1. The selectivity of the obtained Fe3O4@MIPs NPs were elucidated by the different rebinding capability of SMZ and structural related sulfonamides in the mixed solution. The results indicated that the Fe3O4@MIPs had high imprinting factor 9.5 and significant selectivity. A method was developed for enrichment and determination of SMZ in the poultry feed samples with recoveries of duck and chicken feed ranging from 63.3 to 76.5% and 68.7 to 74.7%, respectively and the relative standard deviations (RSD) (<6.7%).
Nanozymes are next-generation artificial enzymes having distinguished features such as cost-effective, enhanced surface area, and high stability. However, limited selectivity and moderate activity of ...nanozymes in the biochemical environment hindered their usage and encouraged researchers to seek alternative catalytic materials. Recently, metal-organic frameworks (MOFs) characterized by distinct crystalline porous structures with large surface area, tunable pores, and uniformly dispersed active sites emerged, that filled the gap between natural enzymes and nanozymes. Moreover, by selecting suitable metal ions and organic linkers, MOFs can be designed for effective bacterial theranostics. In this review, we briefly presented the design and fabrication of MOFs. Then, we demonstrated the applications of MOFs in bacterial theranostics and their safety considerations. Finally, we proposed the major obstacles and opportunities for further development in research on the interface of nanozymes and MOFs. We expect that MOFs based nanozymes with unique physicochemical and intrinsic enzyme-mimicking properties will gain broad interest in both fundamental research and biomedical applications.
•A functionalized magnetic covalent organic framework (Fe3O4@COF-(NO2)2) was fabricated.•Fe3O4@COF-(NO2)2 showed excellent extraction efficiency for neonicotinoids.•The MSPE-HPLC exhibited a wide ...linear range, low LODs, and high enrichment factor.•A sensitive MSPE-HPLC method for monitoring trace insecticides residue in vegetable samples.
A functionalized magnetic covalent organic framework containing the nitro groups (Fe3O4@COF-(NO2)2) with core-shell structure was synthesized for magnetic solid phase extraction (MSPE) of six neonicotinoid insecticides residue in vegetable samples. The structure of Fe3O4@COF-(NO2)2 was investigated by various characterization techniques. The Fe3O4@COF-(NO2)2 exhibits the excellent thermal and chemical stability, high surface area (254.72 m2 g−1), total pore volume (0.19 cm3 g−1), high magnetic responsivity (27.7 emu g−1), which can be used as an ideal adsorbent for rapid isolation and enrichment of target analytes. A sensitive method was developed by using Fe3O4@COF-(NO2)2-based MSPE coupled with HPLC with UV detection. It offered good linearity within the range of 0.1–30 ng mL−1, low limits of detection (S/N = 3) of 0.02–0.05 ng mL−1. Furthermore, high enrichment factors of 170–250 for six neonicotinoid insecticides were obtained. The applicability of Fe3O4@COF-(NO2)2 is demonstrated for measuring trace neonicotinoid residues in vegetable samples with satisfactory recoveries, which ranged from 77.5 to 110.2%. The results indicated that the Fe3O4@COF-(NO2)2 microspheres offer great potential for efficient extraction of neonicotinoid insecticides from complex samples.
