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Sample pretreatment is an essential procedure in pesticide analysis, as the matrix effect can significantly influence the results. In this study, a covalent organic framework (COF) was synthesized using 1,2,4,5-tetrakis-(4-formylphenyl)benzene (TFPB) and benzidine (BD) to mitigate the matrix effect in vegetable and fruit samples. This COF was then used to develop a solid-phase extraction (CSPE) method. In addition, the COF was used to create a magnetic COF (MCOF) for use in magnetic solid-phase extraction (MSPE). The synthesized COF and MCOF were thoroughly characterized using scanning electron microscopy (SEM) for morphological analysis, Fourier-transform infrared spectroscopy (FT-IR) for chemical bond identification, and N2 adsorption–desorption measurements for porosity and surface area assessment. Key pretreatment parameters such as buffers, dilution rate, sorbent dosage, extraction time, elution solvent, and reuse number were optimized. The developed CSPE and MSPE showed excellent purification ability for the matrix of vegetable and fruit samples. The reuse test demonstrated that the synthesized COF and MCOF can be reused up to 15 times. Moreover, the developed CSPE and MSPE showed acceptable recoveries in spiked recovery tests, suggesting that these pretreatment methods were feasible for sample purification in pesticide analysis.

Whether the X-ray emissions of strong jet sources originate from disk+coronas or jets is still controversial. In this work, we constructed a strong jet sample containing 50 flat-spectrum radio quasars, 51 low-synchrotron-peaked BL Lac objects, and 18 intermediate-synchrotron-peaked BL Lac objects to explore the origin of X-ray emissions. Generally, blazars are the typical radio-loud active galactic nucleus with a powerful jet toward the observer, causing their broadband emissions to be boosted. By considering the Doppler boosting effect, we obtain the intrinsic radio–X-ray correlation and the fundamental plane (FP) of black hole activity for the strong jet sources: the intrinsic radio–X-ray correlation is ${L}_{{\rm{R,int}}}\propto {L}_{{\rm{X,int}}}^{1.04}$ , which favor the jet-dominated mode; the intrinsic FP is ${\rm{log}}\,{L}_{{\rm{R}},{\rm{int}}}=(1.07\pm 0.06)\,{\rm{log}}\,{L}_{{\rm{X}},{\rm{int}}}$ $-(0.22\pm 0.10)\,{\rm{log}}\,{M}_{{\rm{BH}}}-(3.77\pm 2.11)$ , which can be interpreted by the hybrid mode of jet+standard disk. Our results suggest that the X-ray emissions of strong jet sources are dominated by the jets, but there may also be a small contribution from the disk. In addition, the radio–X-ray correlation and FP of strong jet sources do not have a significant dependence on the Eddington-ratio.

Citrus huanglongbing (HLB) is one of the most severe diseases affecting the citrus industry, with Diaphorina citri (Hemiptera: Liviidae) serving as its primary natural vector. To understand the genetic diversity and population structure of D. citri in the context of HLB diffusion, we analyzed 13 populations from the HLB diffusion frontier and 25 populations from epidemic areas in China. The HLB diffusion frontier areas refer to the peripheral regions of HLB distribution in China, including the western Zhejiang, southern Jiangsu, northern Jiangxi, northern Hunan, and eastern Sichuan provinces. In contrast, the HLB epidemic areas represent regions in China where HLB is actively widespread and causing significant impacts. We utilized mitochondrial genes (COI, ND5, and Cytb) of D. citri and housekeeping genes (dnaQ, rpoC, and argH) of its endosymbiont Candidatus Carsonella ruddii (Ca. C. ruddii) for this analysis. Our findings revealed that the D. citri and Ca. C. ruddii in different regions showed low haplotype diversity and nucleotide diversity. While the genetic variation in D. citri populations primarily occurred within populations, the endosymbiont showed contrasting patterns in the HLB epidemic areas. We identified three dispersal paths: (1) migration of the Yunnan population to Sichuan, Guizhou, and Guangxi; (2) movement of the Guangdong population to Fujian, Jiangxi, and Zhejiang; and (3) dispersal of the Guangdong population to Hunan and Guangxi. Our study suggests that D. citri populations at the HLB diffusion frontier are predominantly transmitted from neighboring epidemic areas.

Despite evidence that frequent progress monitoring to identify children at-risk of delays and inform early intervention services improves child outcomes, this practice is rare in infant-toddler settings where children could benefit the most from early intervention. Using a descriptive research design within an Implementation Science framework, we evaluated how 10 community-based infant-toddler agencies implemented a standardized progress monitoring assessment using a web application to monitor children's growth and identify children at-risk for delay. An Implementation Index was developed to quantify implementation progress for each agency, which included their percent of tasks completed, and rate of task implementation over time. Staff turnover and high staff:child ratios were associated with low implementation of progress monitoring. The Implementation Index differentiated between agencies that otherwise demonstrated similar implementation rates. Implications for supporting progress monitoring and other evidence-based practices in community-based infant--toddler childcare settings are discussed.