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Alternaria toxin， a secondary metabolite produced by Alternaria， is widely found in food products all over the world and poses a crucial threat to human health. Therefore， the analysis of toxicity and the search for prevention and control measures of the toxin， have become the focus of current research. This study mainly summarizes the toxicity， exposure risk， pollution control， and toxicity intervention methods of four common Alternaria toxins. It provides chain spore mold toxin risk assessment， safety evaluation standards， and a reference for the establishment of prevention and control measures to ensure food safety and preserve human health.

ObjectiveTo establish a non-targeted screening method for emerging contaminants in drinking water based on high-resolution mass spectrometry and apply it to actual water samples.MethodsA total of 9 drinking water samples collected from 3 reservoirs in Shanghai were purified and concentrated by HLB solid phase extraction column， then separated and analyzed by liquid chromatography high-resolution mass spectrometer and gas chromatography high⁃resolution mass spectrometer. The acquired data were analyzed by Thermo Tracefinder， Excel and other software combined with mzCloud and NIST databases. The methodology was verified with representative compound standards. Pesticide and perfluorinated compounds were taken as examples to analyze their pollution status.ResultsA non-targeted analysis strategy based on liquid chromatography and gas chromatography tandem high-resolution mass spectrometry was established. The pollution level of 20 kinds of pesticides and 4 kinds of perfluorinated compounds identified in 9 drinking water samples were higher in the Huangpu River than in the Yangtze River estuary.ConclusionThe established non-targeted screening method by high-resolution mass spectrometry can detect potential emerging contaminants in drinking water without relying on the standards， which provides a powerful technical means for water quality monitoring and risk assessment.

Per- and polyfluoroalkyl substances （PFASs） are a new type of persistent organic pollutants with global attention. They have shown multiple toxic effects due to their persistent accumulation in human body through exposure to environmental media such as drinking water， food， atmosphere， and soil. However， the bone toxicity of PFASs has not attracted enough attention. It is believed that the exposure and accumulation of PFASs in human have a significant impact on the bone health， especially hindering the healthy bone development in infants and adolescents， and aggravating the occurrence of bone loss and fracture in the elder populations. This paper will review the research progress of the effects of PFASs exposure on bone health indicators such as bone mineral density， and discuss the mechanisms of PFAS in bone toxicity. This review will provide references for revealing the effects of PFASs exposure on bone health and their toxic mechanisms.

ObjectiveTo prepare pesticide residues in fruit matrix samples that meet the requirements of homogeneity and stability for the proficiency test.MethodsThe pollution-free apple was selected as the main raw material to prepare the pesticide residue proficiency test samples of myclobutanil and procymidone， and to evaluate the homogeneity and stability. The results of the proficiency test were assessed using robust analysis and Ζ value.ResultsThe homogeneity and stability of the reference materials met the relevant requirements. Among 109 laboratories participated in the proficiency testing， 107 （98.2%） laboratories had satisfactory results. Suspicious test results were reported only in two laboratories， one laboratory for each of the two assessment items.ConclusionAn apple powder matrix sample with pesticide residues is successfully prepared for proficiency test， and could provide an evaluation tool for pesticide residue testing laboratories.

ObjectiveTo prepare a vegetable matrix reference material with pesticide residues and organize a proficiency testing to assess the performance of domestic laboratories on the quantification of pesticide residues.MethodsThrough simulated field planting, chili sprayed with carbofuran and dimethomorph was used as raw materials to prepare chili matrix reference material with pesticide residues. After preparation, the related evaluation and proficiency testing were carried out. Assigned values were obtained from consensus values by robust analysis and the result were assessed using Z-scores.ResultsThe reference material was assessed to be sufficiently homogeneous and stable (all P >0.05). A total of 155 laboratories, from 30 regions in China participated the proficiency testing, while 142 (91.6%), 5 (3.2%) and 8 (5.2%) laboratories had acceptable performance (|z|≤2.0), warning signal (2.0

Existing research concerning the relationships between perceived destination restorative qualities (PDRQs) and tourist well-being mainly adopts traditional quantitative methods such as linear regression and structural equation model, and lacks an in-depth discussion on its internal complexity. Anchored in the special period of COVID-19 epidemic prevention and control, this paper takes Qingdao as the research site, establishes a causal-effect model of tourist well-being (hedonic and eudaemonic well-being) by using fuzzy-set qualitative comparative analysis (fsQCA), and incorporates the variable of "crowding perception" to further explore the configuration conditions of tourist well-being. It is found as follows. ➀ The "fascination" dimension achieved the highest consistency among six influencing factors on tourists' hedonic well-being and eudaemonic well-being, demonstrating that it has an important explanatory power to the formation of tourist well-being. However, none of factors alone was able to create the necessary conditions for tourist well-being. ➁ Nine combinations related to high-level of hedonic and eudaemonic well-being are revealed. The core conditions of hedonic well-being and eudaemonic well-being both involve the "mentally away" dimension, indicating that a strong sense of "mentally away" can serve as an important basis for shaping a high-level of well-being for tourists. ➂ The configurations of tourists' hedonic well-being and eudaemonic well-being are significantly heterogeneous. Compared with hedonic well-being, the core conditions in the configurations of eudaemonic well-being are more complexed. ➃ For tourists hedonic well-being and eudaemonic well-being, the combination with the highest consistency "definitely does not include" the high-level of crowding perception. This paper not only deepens the understanding of formation mechanism of tourist well-being, but also provides practical enlightenment for destination marketing and management. [ABSTRACT FROM AUTHOR]

To reveal the reason for the short life of hub bearings in the front steering axle of a heavy duty truck, the vehicle driving conditions for hub bearing life analysis is worked out with their corresponding load spectra defined. Based on Lundberg-Palmgren and Ioannidis-Harris bearing life theories, a fatigue life analysis model for hub bearings is established with Romax software, and the fatigue life and the damage rate of hub bearings in a 7.5 t front steering axle under rated loading conditions are calculated. The results show that the inner bearing in inner wheel hub meets the design requirements, but the bearings in outer wheel hub don't. Among them the bearing in right outer wheel hub has the shortest life, and there is apparent misalignment between its inner and outer rings with uneven roller loads. Moreover, the direction of resultant force of axial loads acting on inner ring rib deviates from rotating axis, generating bending moment and causing severe stress concentration in both inner and outer rings. [ABSTRACT FROM AUTHOR]

Objective To observe the effect of serum of SD rats lavaged by modified Zuojin decoction on the apoptosis and proliferation of human gastric cancer cells and its mechanism. Methods SD rats were gavaged with modified Zuojin decoction to prepare their sera. Human SGC-7901 and MKN-45 cells were cultured and treated with the sera (0, 25, 50, 100, 200, 400) mL/L. MTT assay was used to observe the effect of drug-containing serum on the proliferation of human gastric cancer cells. Immunofluorescence method was used to detect the expression of ki67 after treatment with the drug-containing serum. The effect of drug-containing serum on the apoptosis of gastric cancer cells was detected by flow cytometry. Western blot analysis was used to detect the protein levels of apoptosis-associated cleaved caspase-3, cleaved caspase-8, cleaved caspase-9, BAX and Bcl2 in SGC-7901 and MKN-45 cells. Results The drug-containing serum significantly inhibited the proliferation and induced the apoptosis of SGC-7901 and MKN-45 cells, and the positive rate of ki67 expression was significantly reduced. The levels of cleaved caspase-3, cleaved caspase-9 and BAX proteins in SGC-7901 and MKN-45 cells increased and the levels of Bcl2 protein decreased. Conclusion The drug-containing serum can significantly inhibit the proliferation and induce the apoptosis of human gastric cancer SGC-7901 and MKN-45 cells, and the mechanism may be related to the activation of mitochondrial pathways.

Objective: To investigate the impact of prenatal exposure to pyrethroid pesticides on neurodevelopment and behavior in a group of one-year old infants., Methods: Three metabolites of pyrethroids (cis-Cl2CA, trans-Cl2CA and 3-PBA) in urine samples of 301 pregnant women enrolled from somewhere of Jiangsu Province were detected, The anthropometrics and the neurodevelopment of their 1-year old infants were assessed using DST scales. The mothers were consent informed before the study., Results: Three metabolites of pyrethroid were detected in 95% of urine samples. The infants were divided into high, medium or low exposure group by the level of pyrethroid in their mothers' urine detected during pregnancy. The difference of neurodevelopment index (DQ) among three groups of one-year old children was significant (P < 0.05), and the association of pyrethroid exposure with neurodevelopment was verified by multiple liner regression analysis (beta = - 0.1453, P < 0.05)., Conclusion: Prenatal exposure to elevated levels of pyrethroid pesticides was associated with reduced neurodevelopment of infants in this population.