Molecular imprinting-based solid-phase extraction (MI-SPE) has been in the spotlight to improve the recognition selectivity and detection sensitivity. MI-SPE provides a powerful tool for ...chemo/bioanalysis in complex matrices and meanwhile, benefits from distinguished advantages such as easy operation, high throughput, low cost, high selectivity and durability. This review proposed the recent advances in molecular imprinting concerning novel preparation strategies of molecularly imprinted polymers (MIPs) and typical applications of MI-SPE. Preparation strategies are highlighted by dividing into ten sections mainly including dummy imprinting, multi-template imprinting, surface imprinting, water-compatible imprinting, restricted access material combining imprinting etc.; each section provides the descriptions about what restrictions led to the emergence of any strategy, strengths/weaknesses of every strategy and universal applications of upgraded MIPs in various SPE modes prior to chromatographic analysis. The potential of MIPs for implementation in routine laboratory activities and scale-up is expected, and finally remaining challenges and future perspectives are proposed.
Display omitted
•Current challenges on MIPs and related imprinting strategies are comprehensively summarized.•Applications of upgraded molecular imprinting based solid-phase extraction are discussed.•The potential of MIPs for implementation in routine laboratory activities and scale-up is summarized.•The future study requirements are highlighted.
In this work, hydrophilic molecularly imprinted nanospheres (MINs) were synthesized via surface imprinting technology and subsequently utilized as dispersant sorbent in matrix solid phase dispersion ...(MSPD) for the extraction of rhodamine B (RhB) as the illogical food additive dye from different foodstuffs, followed by HPLC analysis. By considering hydrophilicity of target analyte, the sol-gel route was chosen for the preparation of MINs in aqueous media at mild conditions. Most importantly, both synthesis and extraction steps were designed and performed in the line of green chemistry and hazardous waste was eliminated to minimize detrimental impact on the operator health and the environment. The reputable experimental design methodology was adopted to assist the condition optimization of MSPD, which comprehends the significance of the factors and their interactions with the least experimental runs. Under optimized MINs-MSPD-HPLC conditions, the detection limit of RhB was down to 0.14 μg kg−1 and excellent linearity over the wide range of 0.5–10000 μg kg−1 was attained. Furthermore, endogenous RhB was found in the tested food samples with relative standard deviations (RSDs) of ≤4.6%, and satisfactory recoveries were from 83.6 to 96.9%. The simple green MINs-MSPD method holds great potential for determination of trace RhB in complicated solid/semi-solid samples, showing rapidity, accuracy and reliability.
Display omitted
•Hydrophilic molecularly imprinted nanospheres (MINs) were synthesized.•MINs based matrix solid phase dispersion (MSPD) was used for Rhodamine B.•Both synthesis and extraction steps were designed in the line of green chemistry.•MSPD variables were simply optimized by experimental design methodology.•MINs-MSPD-HPLC method was applicable to analysis of solid/semi-solid samples.
Amaranthus retroflexus L. is one of the malignant weeds which can cause a reduction in the soybean yield. We found a population of A. retroflexus (R-Q) resistant to fomesafen through the initial ...screening of whole-plant dose response bioassay in the research. The resistance index of the population (R-Q) was 183 times of the sensitive population (S-N). The resistant and sensitive populations were used as experimental materials in the paper. Strand-specific RNA-Seq analyses of R-Q and S-N populations obtained from herbicide-treated and mock-treated leaf samples after treatment were conducted to generate a full-length transcriptome database. We analyzed differentially expressed genes (DEGs) among the R-Q and S-N A. retroflexus populations treated with recommended dose and mock-treated on the 1.sup.st (24 h) and 3.sup.rd (72 h) days to identify genes involved in fomesafen resistance. All 82,287 unigenes were annotated by Blastx search with E-value < 0.00001 from 7 databases. A total of 94,815 DEGs among the three group comparisons were identified. Two nuclear genes encoding PPO (PPX1 and PPX2) and five unigenes belonging to the AP2-EREBP, GRAS, NAC, bHLH and bZIP families exhibited different expression patterns between individuals of S-N and R-Q populations. The A. retroflexus transcriptome and specific transcription factor families which can respond to fomesafen in resistant and susceptible genotypes were reported in this paper. The PPX1 and PPX2 genes of the target enzyme were identified. The study establishes the foundation for future research and provides opportunities to manage resistant weeds better.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The unwillingness of college students to use recycled water has become a key barrier to sewage recycling on campus, and it is critical to strengthen their inclination to do so. This paper used ...college students in Xi'an as a case study and adopted event-related potential technology to explore the effect of social norms on the willingness to use recycled water and the neural mechanism of cognitive processing. The results suggested the following: (1) The existence of social norms might influence college students' willingness to use recycled water. (2) When individuals' willingness to use recycled water is lower than the social norm, there is a bigger feedback-related negative amplitude. (3) College students pay more attention to social norms in groups with closer social distance. These findings can be used to provide a scientific basis for persuading the public to use recycled water from the perspective of the social norm to drive public acceptability.
Molecularly imprinted polymers (MIPs) receive extensive interest, owing to their structure predictability, recognition specificity, and application universality as well as robustness, simplicity, and ...inexpensiveness. Surface-enhanced Raman scattering (SERS) is regarded as an ideal optical detection candidate for its unique features of fingerprint recognition, nondestructive property, high sensitivity, and rapidity. Accordingly, MIP based SERS (MIP-SERS) sensors have attracted significant research interest for versatile applications especially in the field of chemo- and bioanalysis, showing excellent identification and detection performances. Herein, we comprehensively review the recent advances in MIP-SERS sensors construction and applications, including sensing principles and signal enhancement mechanisms, focusing on novel construction strategies and representative applications. First, the basic structure of the MIP-SERS sensors is briefly outlined. Second, novel imprinting strategies are highlighted, mainly including multifunctional monomer imprinting, dummy template imprinting, living/controlled radical polymerization, and stimuli-responsive imprinting. Third, typical application of MIP-SERS sensors in chemo/bioanalysis is summarized from both small and macromolecular aspects. Lastly, the challenges and perspectives of the MIP-SERS sensors are proposed, orienting sensitivity improvement and application expanding.
Sophora flavescens are widely used for their pharmacological effects. As its main pharmacological components, alkaloids and flavonoids are distributed in the root tissues wherein molecular mechanisms ...remain elusive. In this study, metabolite profiles are analyzed using metabolomes to obtain biomarkers detected in different root tissues. These biomarkers include alkaloids, phenylpropanoids, and flavonoids. The high-performance liquid chromatography analysis results indicate the differences in principal component contents. Oxymatrine, sophoridine, and matrine contents are the highest in the phloem, whereas trifolirhizin, maackiain, and kushenol I contents are the highest in the xylem. The transcript expression profiles also show tissue specificity in the roots. A total of 52 and 39 transcripts involved in alkaloid and flavonoid syntheses are found, respectively. Among them, the expression levels of LYSA1, LYSA2, AO2, AO6, PMT1, PMT17, PMT34, and PMT35 transcripts are highly and positively correlated with alkaloids contents. The expression levels of 4CL1, 4CL3, 4CL12, CHI5, CHI7, and CHI9 transcripts are markedly and positively correlated with flavonoids contents. Moreover, the quantitative profiles of alkaloids and flavonoids are provided, and the pivotal genes regulating their distribution in S. flavescens are determined. These results contribute to the existing data for the genetic improvement and target breeding of S. flavescens.
Evapotranspiration (ET) is an important part of the surface energy balance and water balance. Due to imperfect model parameterizations and forcing data, there are still great uncertainties concerning ...ET products. The validation of land surface ET products has a certain research significance. In this study, two direct validation methods, including the latent heat flux (LE) from the flux towers validation method and the water balance validation method, and one indirect validation method, the three-corned hat (TCH) uncertainty analysis, were used to validate and compare seven types of ET products in the Haihe River Basin in China. The products evaluated included six ET products based on remotely-sensed observations (surface energy balance based global land evapotranspiration EB-ET, Moderate Resolution Imaging Spectroradiometer MODIS global terrestrial evapotranspiration product MOD16, Penman–Monteith–Leuning Evapotranspiration version 2 PML_V2, Global Land Surface Satellite GLASS, global land evaporation Amsterdam model GLEAM, and Zhangke evapotranspiration ZK-ET) and one ET product from atmospheric re-analysis data (Japanese 55-year re-analysis, JRA-55). The goals of this study were to provide a reference for research on ET in the Haihe River Basin. The results indicate the following: (1) The results of the six ET products have a higher accuracy when the flux towers validation method is used. Except for MOD16_ET and EB_ET, the Pearson correlation coefficients (R) were all greater than 0.6. The root mean square deviation (RMSD) values were all less than 40 W/m2. The GLASS_ET data have the smallest average deviation (BIAS) value. Overall, the GLEAM_ET data have a higher accuracy. (2) When the validation of the water balance approach was used, the low values of the MOD16_ET were overestimated and the high values were underestimated. The values of the EB_ET, GLEAM_ET, JRA_ET, PML_ET, and ZK_ET were overestimated. According to the seasonal variations statistics, most of the ET products have higher R values in spring and lower R values in summer, and the RMSD values of most of the products were the highest in summer. (3) According to the results of the uncertainty quantification based on the TCH method, the average value of the relative uncertainties of the GLEAM_ET data were the lowest. The relative uncertainties of the JRA_ET and ZK_ET were higher in mountainous areas than in non-mountainous area, and the relative uncertainties of the PML_ET were lower in mountainous areas. The performances of the EB_ET, GLEAM_ET, and MOD16_ET in mountainous and non-mountainous areas were relatively equal. The relative uncertainties of the ET products were significantly higher in summer than in other periods, and they also varied in the different sub-basins.
General Physical Properties of Fermi Blazars Chen, Yongyun; Gu, Qiusheng; Fan, Junhui ...
The Astrophysical journal. Supplement series,
09/2023, Letnik:
268, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Abstract
We study the general physical properties of Fermi blazars using the Fermi fourth source catalog data (4FGL-DR2). The quasi-simultaneous multiwavelength data of Fermi blazars are fitted by ...using the one-zone leptonic model to obtain some physical parameters, such as jet power, magnetic field, and Doppler factor. We study the distributions of the derived physical parameters as a function of black hole mass and accretion disk luminosity. The main results are as follows. (1) For a standard thin accretion disk, the jet kinetic power of most flat-spectrum radio quasars can be explained by the Blandford–Payne (BP) mechanism. However, the jet kinetic power of most BL Lacertae objects (BL Lacs) cannot be explained by either the Blandford–Znajek mechanism or the BP mechanism. The BL Lacs may have advection-dominated accretion flows surrounding their massive black holes. (2) After excluding the redshift, there is a moderately strong correlation between the jet kinetic power and jet radiation power and the accretion disk luminosity for Fermi blazars. These results confirm a close connection between jet and accretion. The jet kinetic power is slightly larger than the accretion disk luminosity for Fermi blazars. (3) There is a significant correlation between jet kinetic power and gamma-ray luminosity and radio luminosity for Fermi blazars, which suggests that gamma-ray luminosity and radio luminosity can be used to indicate the jet kinetic power.
Abstract
We collect a large sample with a reliable redshift detected by the Fermi satellite after 10 yr of data (4FGL-DR2), including blazars, gamma-ray narrow-line Seyfert 1 galaxies (
γ
NLS1s), and ...radio galaxies. The spectral energy distributions of these Fermi sources are fitted by using a second-degree polynomial, and some important parameters including spectral curvature, synchrotron peak frequency, and peak luminosity are obtained. Based on those parameters, we discuss the Fermi blazar sequence and the particle acceleration mechanism. Our main results are as follows: (i) By studying the relationship between the synchrotron peak frequency and the synchrotron peak frequency luminosity, jet kinetic power, and gamma-ray luminosity for jetted active galactic nuclei (AGNs), we find an “L” shape in the Fermi blazar sequence. (ii) There is a significant anticorrelation between the Compton dominance, the black hole spin, and the synchrotron peak frequency for jetted AGNs, respectively. These results support that the
γ
NLS1s and radio galaxies belong to the Fermi blazar sequence. (iii) On the basis of previous work, statistical or stochastic acceleration mechanisms can be used to explain the relationship between the synchrotron peak frequency and synchrotron curvature. For different subclasses, the correlation slopes are different, which implies that the Fermi sources of different subclasses have different acceleration mechanisms. (iv) Flat-spectrum radio quasars and
γ
NLS1s have a higher median spin of a black hole than BL Lac objects and radio galaxies.
Abstract
We study the radio galaxies with known redshifts detected by the Fermi satellite after 10 yr of data (4FGL-DR2). We use a one-zone leptonic model to fit the quasi-simultaneous ...multiwavelength data of these radio galaxies and study the distributions of the derived physical parameters as a function of black hole mass and accretion disk luminosity. The main results are as follows. (1) We find that the jet kinetic power of most radio galaxies can be explained by the hybrid jet model based on ADAFs surrounding Kerr black holes. (2) After excluding the redshift, there is a significant correlation between the radiation jet power and the accretion disk luminosity, while the jet kinetic power is weakly correlated with the accretion disk luminosity. (3) We also find a significant correlation between inverse Compton luminosity and synchrotron luminosity. The slope of the correlation for radio galaxies is consistent with the synchrotron self-Compton (SSC) process. The result may suggest that the high-energy components of radio galaxies are dominated by the SSC process.