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Molybdenum (Mo), an essential mineral, plays a key role in the vital activity of the organism. However, excess Mo in the forage will cause loss of appetite, diarrhea, emaciation, bone injury, joint abnormalities, and anemia in animals. In order to study molybdenosis in the Procapra picticaudata in the animal rescue center, samples of soils, forages, blood, and liver were collected. The mineral contents of all samples were determined, and the blood parameters were also measured. The results showed that the Mo level in the soil and forage in the animal rescue center was significantly higher than that in healthy pastures (p < 0.01). The Mo concentrations in the blood and liver in the P. picticaudata from the animal rescue center were also noticeably higher than those in healthy animals (p < 0.01). The level of Cu in the blood and liver were noticeably lower than those in healthy P. picticaudata (p < 0.01). The superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), and catalase (CAT) were significantly lower than those in healthy animals. Supplementing copper sulfate (CuSO4) could significantly decrease the Mo content in the blood, and cure molybdenosis. In summary, the excessive Mo content in the soil and forage in the animal rescue center had greatly affected physiological parameters and antioxidant capacity. It is likely that the molybdenosis of the P. picticaudata is caused by the high Mo contents in soils and forages. CuSO4 may alleviate molybdenosis in P. picticaudata.

Reducing fruit and vegetable waste and maintaining quality has become challenging for everyone. Nanotechnology is a new and intriguing technology that is currently being implemented in fruit and vegetable preservation. Silver nanomaterials provide superior antibacterial qualities, biodegradability, and biocompatibility, which expands their potential applications in fruit and vegetable preservation. Silver nanomaterials include silver nanocomposites and Ag-MOF, of which silver nanocomposites are mainly composed of silver nanoparticles. Notably, not all kinds of silver nanoparticles utilized in the preservation of fruits and vegetables are thoroughly described. Therefore, the synthesis, mechanism of action, and advancements in research on silver nanocomposites for fruit and vegetable preservation were discussed in this study.

Abstract Background 3D cancer stem cell (CSC) cultures are widely used as in vitro tumor models. In this study, we determined the effects of enriching HCT116 tumor spheres initially cultured in serum-free medium with different concentrations of serum, focusing on the effect of microserum environment stimulation on extraction and biological function of colorectal cancer stem cells (CCSCs). Methods CCSCs were enriched in standard serum-free medium and serum-free medium with different concentrations of serum for 1 week. The expression of CSC-associated markers in CCSCs, and the presence and relative proportion of CSCs (CD133/CD44 cell sorting) were then determined to elucidate the effect of the microserum environment on the preservation of CSC-related features. Further, the tumorigenic capacity of CCSCs was evaluated in an immunodeficiency mouse model. Results Our data indicated that a significantly greater number of spheres with a greater size range and high viability without drastic alteration in biological and structural features, which maintained self‐renewal potential after sequential passages were formed after serum supplementation. Real-time analysis showed that both serum spheres and serum-free spheres displayed similar expression patterns for key stemness genes. Serum spheres showed higher expression of the CSC surface markers CD133 and CD44 than did CSCs spheres cultured in serum-free medium. Adherent cultures in complete medium could adapt to the serum-containing microenvironment faster and showed higher proliferation ability. The addition of serum induced EMT and promoted the migration and invasion of serum globular cells. Compared with serum-free cells and adherent cells, serum spheres showed higher tumor initiation ability. Conclusions Microserum environment stimulation could be an effective strategy for reliable enrichment of intact CCSCs, and a more efficient CSC enrichment method.

Optimal control problems for switched systems how best to switch between different subsystems. In this paper, two kinds of linear quadratic optimal control problems for multistage switched systems composing of both randomness and uncertainty are studied. Chance theory brings us a useful tool to deal with this indeterminacy. Based on chance theory and Bellman's principle, the analytical expressions are derived for calculating both the optimal control input and the optimal switching control law. Optimal control is implemented by genetic algorithm instead of enumerating all the elements of a series of sets whose size grows exponentially. Finally, the results of numerical examples are provided to illustrate the effectiveness of the proposed method.

Due to the degradation of pasture and strict restrictions on grazing ranges in recent years, copper (Cu) deficiency in Yudong black goats has been occurring, mainly manifested as emaciation, anemia, loss of appetite and lack of spirit. To explore the main causes of Cu deficiency in Yudong black goats, 40 black goats (1 year old, 25.11 ± 0.52 kg) were selected for this experiment; among them, 20 Yudong black goats with Cu deficiency from the experimental pasture were used as the experimental group, and 20 healthy Yudong black goats from the control pasture were used as the control group. In the pre-experiment, the mineral contents of the soil, forage, blood, and liver of black goats in both groups were determined, and in formal experiments, blood hematological, biochemical, antioxidant, and hemorheological parameters were analyzed. An experiment on the treatment of Cu deficiency in black goats was also conducted. This study showed that selenium (Se) levels in the soil, forage, blood, and liver from the experimental group were significantly lower than those from the control group (p < 0.01). The content of sulfur (S) in the forage was considerably higher than that of the control group (p < 0.01). The contents of Cu in the blood and liver from the experimental group were significantly lower than that from the control group (p < 0.01), and the content of S was considerably higher than that from the control group (p < 0.01). The blood hematology of the experimental group was affected, as evidenced by a decrease in hemoglobin, hematocrit value, mean corpuscular volume and mean corpuscular hemoglobin. The immunity and antioxidant capacity of black goats in the experiment group were impaired to varying degrees, with significant decreases in ceruloplasmin, immunoglobulin M, immunoglobulin G, glutathione peroxidase, and superoxide dismutase, and substantial increases in malondialdehyde. In addition, the experimental group showed a decrease in blood viscosity as evidenced by the rise in high shear viscosity, low shear viscosity, erythrocyte rigidity index, erythrocyte aggregation index, and erythrocyte deformation index, and a decrease in plasma viscosity. In the treatment experiment, oral administration of copper sulfate solution was carried out on 10 black goats with Cu deficiency. All the Cu deficiency goats were cured, and the Cu content in their bodies rebounded. In summary, low Se soil caused an increase in S content in the forage, and Yudong black goats feeding on high S forage resulted in a decrease in Cu absorption, which led to a secondary Cu deficiency.

Background: With rapid development in agriculture and industry, water polluted with heavy metallic ions has come to be a serious problem. Adsorption-based methods are simple, efficient, and broadly used to eliminate heavy metals. Conventional adsorption materials have the problems of secondary environmental contamination. Hydrogels are considered effective adsorbents, and those prepared from biopolymers are biocompatible, biodegradable, non-toxic, safe to handle, and increasingly used to adsorb heavy metal ions. Aim of review: The natural origin and easy degradability of biopolymer hydrogels make them potential for development in environmental remediation. Its water absorption capacity enables it to efficiently adsorb various pollutants in the aqueous environment, and its internal pore channels increase the specific surface area for adsorption, which can provide abundant active binding sites for heavy metal ions through chemical modification. Key scientific concept of review: As the most representative of biopolymer hydrogels, polysaccharide-based hydrogels are diverse, physically and chemically stable, and can undergo complex chemical modifications to enhance their performance, thus exhibiting superior ability to remove contaminants. This review summarizes the preparation methods of hydrogels, followed by a discussion of the main categories and applications of polysaccharide-based biopolymer hydrogels.

Glucosinolates are a kind of important sulfur-containing anionic hydrophilic natural products in cruciferous vegetables. Under the catalysis of endogenous myrosinase, glucosinolates can be hydrolyzed to produce active substances with anti-cancer, anti-oxidation, antimicrobial and other effects, which have attracted wide attention of researchers. Sulforaphane is a thioglucose monomer with the best anticancer effect and the strongest efficacy. As an effective component of drugs or functional foods, it has high research value and broad application prospects. In this study, the source, structure, properties, functional activities of sulforaphane are summarized, and its extraction technology, separation and purification methods and anticancer applications are systematically introduced. The research prospect is discussed and anticipated, in order to provide research basis and technical support for the research and development of sulforaphane functional components and high value-added utilization.

This Special Issue presents a share of the work published in the journal Foods on pesticide residue monitoring and risk assessment in food [...]

Sulforaphane (SFN) is a natural isothiocyanate compound widely abundant in cruciferous vegetables with multiple bioactive functions. However, traditional analytical methods for the extraction and determination of SFN are cumbersome, time-consuming, and low sensitivity with large amounts of organic solvents. Herein, novel magnetic COF-on-COFs (MB-COFs) were fabricated using Fe3O4 as a magnetic core and COFs-1 grown with COFs-2 as a shell, and they were used as efficient adsorbents of magnetic dispersive solid-phase extraction for rapid quantification of SFN in cruciferous vegetables by combining with HPLC-MS/MS. At the optimal ratio of COFs-1 to COFs-2, MB-COFs had a spherical cluster-like structure and a rough surface, with a sufficient magnetic response for rapid magnetic separation (1 min). Due to the introduction of Fe3O4 and COFs-2, MB-COFs exhibited outstanding extraction efficiencies for SFN (92.5–97.3%), which was about 18–72% higher than that of the bare COFs. Moreover, MB-COFs showed good adsorption capacity (Qm of 18.0 mg/g), rapid adsorption (5 min) and desorption (30 s) to SFN, and favorable reusability (≥7 cycles) by virtue of their unique hierarchical porous structure. The adsorption kinetic data were well fitted by the pseudo-second-order, Ritchie-second-order, intra-particle diffusion, and Elovich models, while the adsorption isotherm data were highly consistent with the Langmuir, Temkin, and Redlich–Peterson models. Finally, under the optimized conditions, the developed method showed a wide linear range (0.001–0.5 mg/L), high sensitivity (limits of quantification of 0.18–0.31 μg/L), satisfactory recoveries (82.2–96.2%) and precisions (1.8–7.9%), and a negligible matrix effect (0.82–0.97). Compared to previous methods, the proposed method is faster and more sensitive and significantly reduces the use of organic solvents, which can achieve the efficient detection of large-scale samples in practical scenarios. This work reveals the high practical potential of MB-COFs as adsorbents for efficient extraction and sensitive analysis of SFN in cruciferous vegetables.

Tea polyphenols (TPs) are important bioactive compounds in tea and have excellent physiological regulation functions. However, the extraction and purification of TPs are key technologies affecting their further application, and the chemical instability, poor bioavailability of TPs are major challenges for researchers. In the past decade, therefore, research and development of advanced carrier systems for the delivery of TPs has been greatly promoted to improve their poor stability and poor bioavailability. In this review, the properties and function of TPs are introduced, and the recent advances in the extraction and purification technologies are systematically summarized. Particularly, the intelligent delivery of TPs via novel nano-carriers is critically reviewed, and the application of TPs nano-delivery system in medical field and food industry is also described. Finally, the main limitations, current challenges and future perspectives are highlighted in order to provide research ideas for exploiting nano-delivery carriers and their application in TPs.

Background: Organophosphorus pesticides (OPs), as insecticides or acaricides, are widely used in agricultural products to ensure agricultural production. However, widespread use of OPs leads to environmental contamination and significant negative consequences on biodiversity, food security, and water resources. Therefore, developing a sensitive and rapid method to determine OPs residues in different matrices is necessary. Originally, the enzyme inhibition methods are often used as preliminary screens of OPs in crops. Many studies on the characteristic of Au nanomaterials have constantly been emerging in the past decade. Combined with anisotropic Au nanomaterials, enzyme inhibition methods have the advantages of high sensitivity, durability, and high stability. Aim of Review: This review aims to summarize the principles and strategies of gold (Au) nanomaterials in enzyme inhibition methods, including colorimetric (dispersion, particle size of Au nanomaterials) and fluorometric (fluorescence energy transfer, internal filtration effect) detection, and electrochemical sensing system (shape of Au nanomaterials, Au nanomaterials combined with other nanomaterials). The application of enzyme inhibition in agricultural products and research progress was also outlined. Next, this review illustrates the advantages of Au nanomaterial-based enzyme inhibition methods compared with conventional enzyme inhibition methods. The detection limits and linear range of colorimetric and fluorometric detection and electrochemical biosensors have also been provided. At last, key perspectives, trends, gaps, and future research directions are proposed. Key Scientific Concepts of Review: Herein, we introduced the technology of enzyme inhibition method based on Au nanomaterials for onsite and infield rapid detection of organophosphorus pesticide.

In order to make the identification and utilization of nutritional quality components in Chinese cabbage more predictive, to obtain ideal raw materials, and to help screen functional Chinese cabbage varieties that have high nutritional value, we conducted a comprehensive evaluation of the nutritional quality of different Chinese cabbage varieties. In this study, 17 nutritional quality indexes of 35 Chinese cabbage varieties, including crude fiber (CF), crude protein (CP), vitamin C (VC), glucose (Glc), fructose (Fru), malic acid (MA), citric acid (CA), oxalic acid (OA), total amino acid (TAA) and CA, K, Mg, P, Cu, Fe, Mn and Zn, were analyzed using diversity analysis, correlation analysis, principal component analysis, membership function analysis and cluster analysis. The results showed that there were different degrees of variation in the 17 nutritional quality indexes, and the coefficients of variation ranged from 11.45% to 91.47%. The correlation analysis found that there were significant or extremely significant correlations between different nutrient elements of Chinese cabbage, which indicated that principal component analysis could be carried out, and the comprehensive score (D value) of different materials could be obtained using principal component analysis and the membership function method. The nutritional quality of Chinese cabbage was classified into five grades by cluster analysis. Finally, a mathematical model for evaluating the nutritional quality of Chinese cabbage was established using the D value and multiple stepwise regression methods, and 10 key indexes were selected from the 17 indexes, which could be used for the rapid identification of the nutritional quality of Chinese cabbage. This study provided a theoretical basis for the nutritional quality evaluation and variety breeding of Chinese cabbage.

At present, nano-carrier materials with antibacterial activity are of great significance. Due to the widespread resistance of many pathogenic microorganisms, it has seriously threatened human health. The natural antimicrobial substances extracted from fruits and vegetables can significantly improve their stability combined with nano-carrier materials. The resistance of pathogenic microorganisms will be substantially reduced, greatly enhancing the effect of active antimicrobial substances. Nanotechnology has excellent research prospects in the food industry, antibacterial preservation, food additives, food packaging, and other fields. This paper introduces nano-carrier materials and preparation techniques for loading and encapsulating active antibacterial substances in detail by constructing a nano-release system for active antibacterial substances. The antibacterial effect can be achieved by protecting them from adverse external conditions and destroying the membrane of pathogenic microorganisms. The mechanism of the slow release of the bacteriostatic active substance is also described. The mechanism of carrier loading and release is mainly through non-covalent forces between the bacteriostatic active substance and the carrier material, such as hydrogen bonding, π-π stacking, van der Waals forces, electrostatic interactions, etc., as well as the loading and adsorption of the bacteriostatic active substance by the chemical assembly. Finally, its wide application in food and medicine is introduced. It is hoped to provide a theoretical basis and technical support for the efficient utilization and product development of bacteriostatic active substances.

Recent studies have shown that the use of mesenchymal stem/stromal cells (MSCs) may be a promising strategy for treating spinal cord injury (SCI). This study aimed to explore the effectiveness of human umbilical cord-derived MSCs (hUC-MSCs) with different administration routes and dosages on SCI rats. Following T10-spinal cord contusion in Sprague-Dawley rats (N = 60), three different dosages of hUC-MSCs were intrathecally injected into rats (SCI-ITH) after 24 h. Intravenous injection of hUC-MSCs (SCI-i.v.) and methylprednisolone reagent (SCI-PC) were used as positive controls (N = 10/group). A SCI control group without treatment and a sham operation group were injected with Multiple Electrolyte Injection solution. The locomotor function was assessed by Basso Beattie Bresnahan (BBB) rating score, magnetic resonance imaging (MRI), histopathology, and immunofluorescence. ELISA was conducted to further analyze the nerve injury and inflammation in the rat SCI model. Following SCI, BBB scores were significantly lower in the SCI groups compared with the sham operation group, but all the treated groups showed the recovery of hind-limb motor function, and rats receiving the high-dose intrathecal injection of hUC-MSCs (SCI-ITH-H) showed improved outcomes compared with rats in hUC-MSCs i.v. and positive control groups. Magnetic resonance imaging revealed significant edema and spinal cord lesion in the SCI groups, and significant recovery was observed in the medium and high-dose hUC-MSCs ITH groups. Histopathological staining showed that the necrotic area in spinal cord tissue was significantly reduced in the hUC-MSCs ITH-H group, and the immunofluorescence staining confirmed the neuroprotection effect of hUC-MSCs infused on SCI rats. The increase of inflammatory cytokines was repressed in hUC-MSCs ITH-H group. Our results confirmed that hUC-MSC administered via intrathecal injection has dose-dependent neuroprotection effect in SCI rats.

The soybean aphid poses a severe threat to soybean quality and yield by sucking phloem sap and transmitting plant viruses. An early-maturing and highly resistant soybean landrace, Fangzheng Moshidou, with markedly reduced aphid colonization has been identified by screening of aphid-resistant soybean accessions. In a population derived from the cross of Fangzheng Moshidou with the susceptible cultivar Beifeng 9, resistance was conferred by a single dominant gene. Three linked markers, Satt114, Satt334, and Sct_033, on chromosome 13 were identified by bulked-segregant analysis. Additional simple-sequence repeat and single-nucleotide polymorphism (SNP) markers were developed for gene mapping. The resistance of Fangzheng Moshidou was fine-mapped to the interval between the SNP markers YCSNP20 and YCSNP80, corresponding to 152.8 kb in the Williams 82 assembly 2 genome. This region was near the reported loci Rag2 and Rag5 but did not overlap the interval containing them. A unique haplotype is described for Fangzheng Moshidou that distinguishes it from soybean accessions PI 587972, PI 594879, and PI 567301B in the interval containing Rag2 and Rag5. These results indicate that Fangzheng Moshidou harbors a novel gene at a tightly linked resistance locus, designated as RagFMD. Fourteen candidate genes were annotated in the fine-mapping region, including seven NBS-LRR genes, which are usually considered resistance genes in plant defense. Most of these candidate genes showed variations distinguishing the resistant and susceptible parents and some genes also showed differences in expression between the two parental lines and at several times after aphid infestation. Isolation of RagFMD would advance the study of molecular mechanisms of soybean aphid resistance and contribute to precise selection of resistant soybeans.

Flowering time is an important trait that determines the breeding process of ornamental plants. The flowering period of lotus (Nelumbo nucifera Gaertn.) is mainly concentrated in June–August. During this period, the weather is hot and there are few tourists, which made many lotus scenic spots difficult to operate. People have a strong demand for early flowering lotus cultivars. In this paper, 30 lotus cultivars with high ornamental value were selected as materials and their phenological periods were observed for two consecutive years in 2019 and 2020. A number of cultivars with early flowering potential and stable flowering periods, such as ‘Fenyanzi’, ‘Chengshanqiuyue’, ‘Xianghumingyue’ and ‘Wuzhilian’, were screened by K-Means clustering method. The relationship between accumulated temperature and flowering time of 19 lotus cultivars at different growth stages was analyzed. It was found that lotus cultivars with early flowering traits could adapt well to the changes of early environmental temperature and were not affected by low temperature. On the other hand, by analyzing the relationship between different traits and flowering time of three typical cultivars, such as rhizome weight, phenological period, etc., it shows that the nutrient content of the rhizome and the early morphology of plants will affect the flowering time. These results provide a reference for the formation of a systematic lotus early flowering cultivar breeding mechanism and the establishment of a perfect flowering regulation technology system, which can further improve the ornamental value of lotus and promote industrial development.

Cruciferous vegetables are rich in glucosinolates, which can be metabolized to produce the antitumor compound indole-3-carbinol (I3C). The conventional solvent extraction method for I3C is inefficient. To improve the extraction efficiency of I3C from cruciferous vegetables, we prepared a metal-organic framework (MOF) material (Fe3O4@Zn-Al-LDH@B-D-MIL-100). First, Fe3O4 nanoparticles were introduced to layered double hydroxides by in situ polymerization. Then, the MOF material was grown on the surface of the layered double hydroxide by co-precipitation and the layer-by-layer self-assembly method. This gave Fe3O4@Zn-Al-LDH@B-D-MIL-100, which was characterized using a variety of techniques. The results showed that Fe3O4@Zn-Al-LDH@B-D-MIL-100 had a double-layer porous structure, excellent superparamagnetism (11.54955 emu/g), a large specific surface area (174.04 m2/g), and a pore volume (0.26 cm3/g). The extraction conditions for I3C were optimized. Non-linear fitting of the static adsorption model showed that the adsorption was mainly monolayer. Fe3O4@Zn-Al-LDH@B-D-MIL-100 had fast adsorption kinetics and could extract 95% of I3C in 45 min. It is superior to the traditional solvent extraction method because of its high enrichment efficiency in a short time and environmental friendliness. The successful preparation of the new nanomaterial will provide a new reference for the enrichment and extraction of the I3C industry.

In this study, a novel metal-organic framework (M-ZIF-8@ZIF-67) was successfully prepared using the single layer Fe3O4-ZIF-8 as magnetic core and wrapped a layer of ZIF-67 outer. This M-ZIF-8@ZIF-67 was employed as an adsorbent for the adsorption and removal of fipronil and its metabolites from environmental water and cucumber samples. The characterization results suggested that M-ZIF-8@ZIF-67 has the double layer structure a polyhedral structure with uniform pores, while ZIF-67 was successfully coated on the surface of Fe3O4-ZIF-8. The unique structure endowed M-ZIF-8@ZIF-67 a high surface area (219 m2/g) and high adsorption capacity for fipronil, fipronil desulfinyl, fipronil sulfide and fipronil sulfone. To our knowledge, this is the first report detailing the adsorption properties of M-ZIF-8@ZIF-67 with double layer structure relating to the adsorption and removal of pesticides. Furthermore, the adsorption model analysis demonstrated that the static adsorption data fitted the Freundlich bimolecular layer adsorption model better than the Langmuir monolayer adsorption model. This study indicates that M-ZIF-8@ZIF-67 has significant potential in the adsorption and removal of fipronil and its metabolites in water and vegetable samples.

Carbendazim (CBZ), a systemic, broad-spectrum benzimidazole fungicide, is widely used to control fungal diseases in agricultural products. Its residues might pose risks to human health and the environment. Therefore, it is warranted to establish a rapid and reliable method for its residual quantification. Herein, we proposed a competitive assay that combined aptamer (DNA) specific recognition and bimetallic nanozyme gold@platinum (Au@Pt) catalysis to trace the CBZ residue. The DNA was labeled onto bimetallic nanozyme Au@Pt surface to produce Au@Pt probes (Au@Pt-DNA). The magnetic Fe3O4 was functionalized with a complementary strand of DNA (C-DNA) to form Fe3O4 probes (Fe3O4-C-DNA). Subsequently, the CBZ and the Fe3O4 probes competitively react with Au@Pt probes to form two Au@Pt-DNA biosensors (Au@Pt-ssDNA-CBZ and Au@Pt-dsDNA-Fe3O4). The Au@Pt-ssDNA-CBZ biosensor was designed for qualitative analysis through a naked-eye visualization strategy in the presence of CBZ. Meanwhile, Au@Pt-dsDNA-Fe3O4 biosensor was developed to quantitatively analyze CBZ using a multifunctional microplate reader. A competitive assay based on the dual-mode Au@Pt-DNA biosensors was established for onsite sensitive determination of CBZ. The limit of detection (LOD) and recoveries of the developed assay were 0.038 ng/mg and 71.88-110.11%, with relative standard deviations (RSDs) ranging between 3.15 and 10.91%. The assay demonstrated a good correlation with data acquired from liquid chromatography coupled with mass spectrometry/mass spectrometry analysis. In summary, the proposed competitive assay based on dual-mode Au@Pt-DNA biosensors might have a great potential for onsite sensitive detection of pesticides in agro-products.

The demand for Chinese chives is growing as they are also rich in vitamins, fiber, and sulfur nutrients. Chinese chives should be sprayed with imidacloprid to control pests and diseases to safeguard their yield and to meet the demands of East Asian consumers for Chinese chives. Overspraying of imidacloprid can lead to residues in Chinese chives, posing a severe risk to human health. To reduce the harmful effects of imidacloprid residues on humans, we investigated the imidacloprid dissipation pattern and the final residue on Chinese chives using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Good linearity (R2= 0.9988), accuracy (expressed as recovery % of 78.34–91.17%), precision [expressed as relative SDs (RSDs) of 0.48–6.43%], and sensitivity [a limit of quantification (LOQ) ≤ 8.07 × 104 mg/kg] were achieved. The dissipation dynamics were consistent with the first-order kinetics, with a half-life of 2.92 days. The final residual levels on Chinese chives were 0.00923–0.166 mg/kg, which is lower than the maximum residue limits (MRLs) of 1 mg/kg for imidacloprid on Chinese chives. A risk assessment index of

The construction of deep foundation pits adjacent to existing subway tunnels faces enormous challenges, and once a safety accident occurs, there are often mass injuries that cause substantial economic losses. However, there are many shortcomings and defects in the traditional methods of assessing the safety of the pit itself and the existing tunnel in the construction of the deep foundation pit adjacent to existing tunnels. This study establishes an optimized complex network-based dynamic risk assessment model to dynamically assess the overall risk of deep foundation pits in adjacent existing tunnels systematically, solving the challenges of inaccurate risk assessment and inaccurate description of correlations between nonstationary time series data. In this study, we first divide the monitoring data into time windows and describe the correlation between nonstationary time-series monitoring data within each window based on the MF-DCCA method and the threshold method, and establish the adjacency matrix to prepare for the establishment of an optimized complex network model. Secondly, based on the adjacency matrix, a complex network model under different time windows is constructed, and risk assessment indexes are established through the topological parameters of the complex network model to explore the evolution of risk in time and space, so as to realize the risk distribution and quantitative evolution assessment of the system which is deep foundation pit adjacent to existing subway tunnels. Finally, the proposed method is tested by taking the Nanning underground comprehensive utilization project as an example. The results show that this method can quantify the risk of the construction of deep foundation pits adjacent to existing tunnels more effectively than the traditional method to describe the evolution law better. It has important guiding significance for strengthening the safety risk monitoring and safety management of the construction system of deep foundation pits adjacent to existing tunnels.

Accidents occur frequently while constructing deep foundation pits for metro stations, thereby risking substantial economic losses and casualties. To subject the construction of such pits to scientific and rational risk assessment and overcome the limitations of existing risk evaluation models and risk fusion problems, proposed here is a risk-assessment model for such pits based on fuzzy evidential reasoning and the two-tuple linguistic analytic network process (TL-ANP). First, the risk loss indicators are optimized, the weights of different risk events and of each risk loss indicator in the metro-station deep-foundation-pit construction project are calculated using TL-ANP, and trapezoidal fuzzy numbers are used to describe the occurrence probability of each risk event and loss. Second, relying on a table of expert weight indices, the best–worst method based on generalized interval-valued trapezoidal fuzzy numbers is used to determine the weights of experts. Finally, the overall risk grade of the construction project is evaluated by aggregating the risk levels of all risk events through an evidence-reasoning algorithm. The analysis results for a deep foundation pit for a station on Line 5 of Nanning Metro show that the model provides a quantitative basis for determining expert weights and risk loss weights reasonably and improving the reliability of the evaluation system. Also, not only does applying the method show that such a construction project can be judged as having a certain risk grade, but more importantly it can identify the key factors and loss indicators affecting the overall risk grade of the pit, whereupon risk control measures can be adopted in a targeted manner. In comparison with traditional methods, the proposed method is shown to be practical and effective, providing a reference basis for analyzing the risks of similar projects in the future and guaranteeing construction safety.

Self-fertilization rate is an essential index of lotus reproductive system development, and pollen activity is a key factor affecting lotus seed setting rate. Based on cytology and molecular biology, this study addresses the main reasons for the low self-set rate of double lotus. It takes two different double lotus breeds into consideration, namely ‘Sijingganshan’ with a low self-crossing rate and ‘Jinfurong’ with a high self-crossing rate. Cytological analysis results showed that the pollen abortion caused by excessive degradation of tapetum during the single phase was the root cause for the low self-mating rate of double lotus. Subsequent transcriptome analysis revealed that the gene NnPTC1 related to programmed tapetum cell death was significantly differentially expressed during the critical period of abortion, which further verified the specific expression of NnPTC1 in anthers. It was found that the expression level of NnPTC1 in ‘Sijingganshan’ at the mononuclear stage of its microspore development was significantly higher than that of ‘Jinfurong’ at the same stage. The overexpression of NnPTC1 resulted in the premature degradation of the tapetum and significantly decreased seed setting rate. These results indicated that the NnPTC1 gene regulated the pollen abortion of double lotus. The mechanism causing a low seed setting rate for double lotus was preliminarily revealed, which provided a theoretical basis for cultivating lotus varieties with both flower and seed.

Imidacloprid is one of the most commonly used insecticides for managing pests, thus, improving the quality and yield of vegetables. The abuse/misuse of imidacloprid contaminates the environment and threatens human health. To reduce the risk, a colorimetric enzyme-linked immunoassay assay (Co-ELISA) and chemiluminescence enzyme-linked immunoassay assay (Cl-ELISA) were established to detect imidacloprid residues in vegetables. The linear range of Co-ELISA ranged between 1.56 μg/L and 200 μg/L with a limit of detection (LOD) of 1.56 μg/L. The values for Cl-ELISA were 0.19 μg/L to 25 μg/L with an LOD of 0.19 μg/L, which are lower than those of Co-ELISA. Fortifying Chinese cabbage, cucumber, and zucchini with imidacloprid at 10, 50, and 100 μg/L yielded recoveries between 81.7 and 117.6% for Co-ELISA and at 5, 10, and 20 µg/L yielded recoveries range from 69.7 to 120.6% for Cl-ELISA. These results indicate that Cl-ELISA has a high sensitivity and a rapid detection time, saving cost (antigen and antibody concentrations) and serving as a more efficient model for the rapid detection of imidacloprid residue.

In this study, a novel composite material prepared by using deep eutectic solvent (tetrabutylammonium chloride-dodecanol, DES5) functionalized magnetic MWCNTs−ZIF−8 (MM/ZIF−8@DES5) was employed as an adsorbent for the magnetic solid-phase extraction of six pyrethroids from tea drinks. The characterization results show that MM/ZIF−8@DES5 possessed sufficient specific surface area and superparamagnetism, which could facilitate the rapid enrichment of pyrethroids from tea drink samples. The results of the optimization experiment indicated that DES5, which comprised tetrabutylammonium chloride and 1-dodecanol, was selected for the next experiment and that the adsorption properties of MM/ZIF−8@DES5 were higher than those of MM/ZIF−8 and M-MWCNTs. The validation results show that the method has a wide linear range (0.5–400 μg L−1, R2 ≥ 0.9905), low LOD (0.08–0.33 μg L−1), and good precision (intra-day RSD ≤ 5.6%, inter-day RSD ≤ 8.6%). The method was successfully applied to the determination of pyrethroids in three tea drink samples.

Because deep foundation pits and tunnels are deformation-sensitive structures, the safety of these projects is generally affected by coupled risks. In deep foundation pit construction, if the existing tunnel structure adjacent to the deposit is damaged, it can produce a severe group disaster. It is necessary to identify an efficient risk analysis model to study the dynamic coupled risk of deep foundation pit projects adjacent to existing underpass tunnels and to analyze the risk evolution law to achieve effective real-time safety control. This study proposes a coupled risk analysis model using the N–K model and dynamic Bayesian network to construct deep foundation pits in adjacent existing underpass tunnels. The model is predicated on association rules to explore the interrelationship between risk factors to build a dynamic Bayesian network structure. In addition, the N–K model is utilized to quantify coupled risks under such complex working conditions and to optimize the dynamic Bayesian network structure. The developed model clarifies the risk coupling mechanism of deep foundation pit construction adjacent to an existing underpass tunnel, finds the critical points in the risk transfer process, and conducts dynamic risk prediction and accident causation diagnosis for the coupled risk to realize the dynamic control of the coupled risk in the adjacent existing underpass tunnel construction. Taking the Nanning underground comprehensive utilization project as an example, the validity and applicability of the proposed approach were tested. The results showed that the model is feasible and has application potential, providing effective decision support for safety control while constructing deep foundation pits adjacent to existing tunnels.

Background: This study aims to evaluate the quality of preclinical data, determine the effect sizes, and identify experimental measures that inform efficacy using mesenchymal stromal (or stem) cells (MSC) therapy in animal models of rheumatoid arthritis (RA). Methods: Literature searches were performed on MSC preclinical studies to treat RA. MSC treatment effect sizes were determined by the most commonly used outcome measures, including paw thickness, clinical score, and histological score. Findings: A total of 48 studies and 94 treatment arms were included, among which 42 studies and 79 treatment arms reported that MSC improved outcomes. The effect sizes of RA treatments using MSC, when compared to the controls, were: paw thickness was ameliorated by 53.6% (95% confidence interval (CI): 26.7% −80.4%), histological score was decreased by 44.9% (95% CI: 33.3% −56.6%), and clinical score was decreased by 29.9% (95% CI: 16.7% −43.0%). Specifically, our results indicated that human umbilical cord derived MSC led to large improvements of the clinical score (−42.1%) and histological score (−51.4%). Interpretation: To the best of our knowledge, this meta-analysis is to quantitatively answer whether MSC represent a robust RA treatment in animal models. It suggests that in preclinical studies, MSC have consistently exhibited therapeutic benefits. The findings demonstrate a need for considering variations in different animal models and treatment protocols in future studies using MSC to treat RA in humans to maximise the therapeutic gains in the era of precision medicine. Funds: NIH [1DP2CA195763], Baylx Inc.: BI-206512, NINDS/NIH Training Grant [Award# NS082174]. Keywords: Mesenchymal stromal (or stem) cells, MSC, Rheumatoid arthritis, Pre-clinical study, Clinical trials, Meta-analysis

Drug residues, organic dyes, heavy metals, and other chemical pollutants not only cause environmental pollution, but also have a serious impact on food safety. Timely and systematic summary of the latest scientific advances is of great importance for the development of new detection technologies. In particular, molecularly imprinted polymers (MIPs) can mimic antibodies, enzymes and other biological molecules to recognize, enrich, and separate contaminants, with specific recognition, selective adsorption, high affinity, and strong resistance characteristics. Therefore, MIPs have been widely used in chemical analysis, sensing, and material adsorption. In this review, we first describe the basic principles and production processes of molecularly imprinted polymers. Secondly, an overview of recent applications of molecularly imprinted polymers in sample pre-treatment, sensors, chromatographic separation, and mimetic enzymes is highlighted. Finally, a brief assessment of current technical issues and future trends in molecularly imprinted polymers is also presented.

Rheumatoid arthritis (RA) is an inflammatory disease of the joints, which causes severe pain and excessive systemic circulation of harmful inflammatory cytokines. Current treatments are limited, with some patients not responding well, and some experiencing severe and detrimental side effects. Mesenchymal stem cells (MSC) are cell-based therapeutics being evaluated as potent immunomodulators in RA and may provide relief to patients not responding well to drug-based treatments. We evaluated the safety and efficacy of BX-U001 human umbilical cord tissue–derived mesenchymal stem cells (hUC-MSC) to treat RA, in support of a successful investigational new drug application. A collagen-induced arthritis (CIA) mouse model of RA was established in DBA/1 J mice. Mice from the treatment assessment group were given a tail vein infusion of hUC-MSC 24 days after primary RA induction, while control assessment (CA) group mice were given cell-free carrier solution. All animals were evaluated daily for RA symptoms via clinical scoring, blood was taken periodically for cytokine analysis, and mice were dissected at end point for histological analysis. A linear mixed model was used to compare the rate of change among groups. The clinical scores of TA group were significantly reduced compared with CA group ( P < 0.01), indicating therapeutic effects. The histological scores of the joints in TA group were significantly lower than those in the CA group ( P < 0.05), but had no significant difference compared with Healthy groups ( P > 0.05). The concentration of (interleukin) IL-6 in TA group was significantly reduced by 80.0% ( P < 0.0001) 2 days after treatment and by 93.4% at the experimental endpoint compared with levels prior to hUC-MSC injection. A single intravenous infusion of hUC-MSC (2 × 10 6 cells/mouse), to CIA-induced DBA/1 J mice, resulted in significant alleviation of RA symptoms and may provide significant therapeutic benefits in humans.

Yellow sarson (Brassica rapa ssp. trillocularis) is an important rapeseed-mustard species of Brassica rapa due to its high seed oil content. Glycerolipids and fatty acid composition affect seed germination and determine the quality of seed oil. To date, no information is available on the composition of individual glycerolipids in this species. Therefore, in this study the glycerolipid profiling of yellow sarson seeds was performed using ultra high performance liquid chromatography coupled to triple time-of-flight mass spectrometry (UPLC-Triple-TOF-MS). A fast and efficient chromatographic separation of glycerolipids was accomplished based on an UPLCTM BEH C8 column within 22 min. In ESI positive ion mode, TOF-MS scan-information dependent acquisition-product ion scan was carried out to acquire both high resolution MS and MS/MS information from one injection. According to MS/MS spectra, predominant fragmentation patterns of glycerolipids were elucidated in detail. Based on retention time, accurate mass, isotopic distribution, and fragmentation patterns, the composition of 144 glycerolipids and fatty acids were finally identified in yellow sarson seeds, including 77 triacylglycerols, 32 diacylglycerols, 18 sulfoquinovosyl-diacylglycerols, 5 monogalactosyl-diaclyglycerols, and 12 digalactosyl-diacylglycerols. Of them, the most abundant glycerolipids in yellow sarson seeds were triacylglycerols, the major storage form of seed oil in plants. In addition, diacylglycerols were found as a minor component of glycerolipids. The lowest amounts of glycerolipids detected in seeds were glycosyl-acylglycerols. The results revealed the composition and relative content of glycerolipids in yellow sarson seeds, which will provide a more comprehensive assessment of the quality of seed oil and also help to select functional cultivars with higher beneficial glycerolipids. This profiling method has the advantages of high throughput, high sensitivity and good accuracy, which will provide a reliable analysis platform for glycerolipids metabolism in plants.

A simple, sensitive and effective magnetic solid-phase extraction (MSPE) technique was developed for the extraction of pyrethroid pesticides from environmental water samples, followed by gas chromatography tandem triple quadrupole mass spectrometry determination. An adsorbent of magnetic zeolitic imidazolate framework-8@deep eutectic solvent (M-ZIF-8@DES) was prepared using deep eutectic solvent coated on the surface of M-ZIF-8. The features of M-ZIF-8@DES were confirmed by material characterizations, and the results indicated that M-ZIF-8@DES has a good magnetism (61.3 emu g−1), a decent surface area (96.83 m2 g−1) and pore volume (0.292 mL g−1). Single factor experiments were carried out to investigate the effect of different conditions on the performance of MSPE. Under the optimal conditions, the developed method performs good linearity (R2 ≥ 0.9916) in the concentration range of 1−500 μg L−1. The limits of detection were in the range of 0.05−0.21 μg L−1 (signal/noise = 3/1). The intraday relative standard deviation (RSD) and interday RSD were less than 9.40%. Finally, the proposed technique was applied for the determination of pyrethroid pesticides in environmental water samples. This work shows the potential of DES-modified metal-organic frameworks for different sample pretreatment techniques.

As persistent organic pollutants, dichlorodiphenyltrichloroethanes (DDTs) and their metabolites pose considerable risks to human health and the environment. Therefore, monitoring DDTs in the environment is essential. Here, we developed a green, simple, and effective magnetic solid-phase extraction (MSPE) method coupled with gas chromatography tandem triple-quadrupole mass spectrometry to determine the DDT content of environmental water samples. A magnetic ionic liquid (IL) adsorbent was developed based on a modified magnetic multiwalled carbon nanotube/zeolitic imidazolate framework-8 (MM/ZIF-8/IL), synthesized by immobilizing the IL on the surface of MM/ZIF-8. We confirmed successful synthesis of MM/ZIF-8/IL by material characterization, and our results suggested that the MM/ZIF-8/IL had a high Brunauer−Emmett−Teller surface area (159.9 m2 g−1), good thermostability (−1). Several experimental conditions affecting the MSPE efficiency were optimized. Under the best conditions, good detection linearity was achieved (0.5−500 µg L−1) with determination coefficients ranging from 0.9927 to 0.9971. The lower limits of detection (0.0016−0.0072 µg L−1) also had good precision, having an intraday relative standard deviation (RSD) ≤ 6.5% and an interday RSD ≤ 8.9%. Finally, we used the as-developed method to determine DDT levels in environmental water samples.

Molecular imprinting technology (MIT), also known as molecular template technology, is a new technology involving material chemistry, polymer chemistry, biochemistry, and other multi-disciplinary approaches. This technology is used to realize the unique recognition ability of three-dimensional crosslinked polymers, called the molecularly imprinted polymers (MIPs). MIPs demonstrate a wide range of applicability, good plasticity, stability, and high selectivity, and their internal recognition sites can be selectively combined with template molecules to achieve selective recognition. A molecularly imprinted fluorescence sensor (MIFs) incorporates fluorescent materials (fluorescein or fluorescent nanoparticles) into a molecularly imprinted polymer synthesis system and transforms the binding sites between target molecules and molecularly imprinted materials into readable fluorescence signals. This sensor demonstrates the advantages of high sensitivity and selectivity of fluorescence detection. Molecularly imprinted materials demonstrate considerable research significance and broad application prospects. They are a research hotspot in the field of food and environment safety sensing analysis. In this study, the progress in the construction and application of MIFs was reviewed with emphasis on the preparation principle, detection methods, and molecular recognition mechanism. The applications of MIFs in food and environment safety detection in recent years were summarized, and the research trends and development prospects of MIFs were discussed.

Due to their unique optical properties, narrow size distributions, and good biological affinity, gold nanoparticles have been widely applied in sensing analysis, catalytic, environmental monitoring, and disease therapy. The color of a gold nanoparticle solution and its maximum characteristic absorption wavelength will change with the particle size and inter-particle spacing. These properties are often used in the detection of hazardous chemicals, such as pesticide residues, heavy metals, banned additives, and biotoxins, in food. Because the gold nanoparticles-colorimetric sensing strategy is simple, quick, and sensitive, this method has extensive applications in real-time on-site monitoring and rapid testing of food quality and safety. Herein, we review the preparation methods, functional modification, photochemical properties, and applications of gold nanoparticle sensors in rapid testing. In addition, we elaborate on the colorimetric sensing mechanisms. Finally, we discuss the advantages and disadvantages of colorimetric sensors based on gold nanoparticles, and directions for future development.

Monitoring of low levels of chlorsulfuron in environmental water samples is important. Although several detection methods have been developed, they all have some drawbacks, such as being time-consuming, requiring expensive instruments and experienced operators, and consuming large volumes of organic solvents. There is an urgent need for a simple, rapid, and inexpensive detection method for chlorsulfuron. Herein, such a method was developed using anti-aggregation of gold nanoparticles (AuNPs) in the presence of acetamiprid in agricultural irrigation water samples. Aggregation of the AuNPs was induced by acetamiprid, and this produced a distinct color change from Bordeaux red to blue. However, the strong hydrogen bonding interaction between chlorsulfuron and acetamiprid could inhibit AuNP aggregation. The effect of chlorsulfuron on the anti-agglomeration behavior of AuNPs was monitored by ultraviolet–visiblespectroscopy (UV-Vis) and the naked eye over a concentration range 0.1–100 mg/L. The detection limit for chlorsulfuron was 0.025 mg/L (signal-to-noise ratio of three). This colorimetric method was successfully applied to the determination of chlorsulfuron in spiked tap water and agricultural irrigation water with satisfactory recoveries (76.3%–94.2%).

Magnetic solid-phase extraction is an effective and convenient sample pretreatment technique that has received considerable interest in recent years. A lot of research indicated that magnetic nanocarbon-material-based composites have good application prospects as adsorbents for magnetic solid-phase extraction of pesticides. Herein, a novel zeolitic imidazolate framework based on magnetic multiwalled carbon nanotubes (M-M-ZIF-67) has been prepared as an adsorbent for magnetic solid-phase extraction of nine organochlorine pesticides from agricultural irrigation water samples. The obtained M-M-ZIF-67 material possessed porous surfaces and super-paramagnetism due to the utilization of magnetic multiwalled carbon nanotubes as the magnetic kernel and support. To evaluate the extraction performance of the M-M-ZIF-67, the main parameters that affected the extraction efficiency were researched. Under the optimal conditions, a good linearity for the nine organochlorine pesticides was achieved with the determination coefficients (R2) higher than 0.9916. The limits of detection (signal/noise = 3:1) were in the range 0.07–1.03 µg L−1. The recoveries of all analytes for the method at spiked levels of 10 and 100 µg L−1 were 74.9–116.3% and 75.1–112.7%, respectively. The developed M-M-ZIF-67 based magnetic solid-phase extraction method has a potential application prospect for the monitoring of trace level of organochlorine pesticides in environmental water samples.

Various highly sensitive and selective analytical methods have been used to monitor metsulfuron-methyl residue in the environment. However, these methods involve costly instruments and complex, time-consuming operations performed in laboratories. Here, a rapid, convenient, and sensitive colorimetric sensor based on anti-aggregation of gold nanoparticles (AuNPs) is demonstrated for the rapid detection of metsulfuron-methyl in agricultural irrigation water. The AuNPs could be induced to aggregate in the presence of melamine and exhibited a distinct color change from wine-red to blue. The aggregation was suppressed by a strong hydrogen-bonding interaction between metsulfuron-methyl and melamine. The differences of the absorbance at 523 nm (ΔA523) and the color change was linearly related to metsulfuron-methyl concentration over the range 0.1–100 mg/L, as observed visually and by UV-vis (Ultraviolet-visible) spectrometry. The detection limit of the sensor was as low as 0.05 mg/L (signal/noise = 3), and was used to determine metsulfuron-methyl in spiked water and in agricultural irrigation water samples. Recoveries were in the range of 71.2–100.4%, suggesting that the colorimetric sensor was suitable for the determination of metsulfuron-methyl in agricultural water samples.

We present a directly competitive fluorescence assay for highly sensitive detection of melamine in milk using magnetic dummy molecularly imprinted polymers (MDMIPs). The detection principle is based on competitive binding between the fluorescent label and melamine on the MDMIPs. The fluorescent label was obtained by combining fluorescein isothiocyanate (FITC) with melamine in ethanol and water. MDMIPs were prepared on the surface of Fe3O4@SiO2 nanoparticles using 2,4-diamino-6-methyl-1,3,5-triazine as dummy template. The MDMIPs were characterized and their adsorption capacity was evaluated based on their static adsorption and Scatchard analysis. Results suggest that MDMIPs were successfully coated on the Fe3O4@SiO2 surface and had a core–shell structure. Adsorption experiments suggested that the MDMIPs had higher specific recognition capacities for melamine and FITC–melamine (FITC-Mel) than did magnetic dummy molecularly non-imprinted polymers. Competitive binding between FITC-Mel and melamine was performed under the optimum conditions to determine melamine quantitatively. The linear range of this fluorescence assay was 0.1–20 mg/L for melamine detection. The detection limit was 0.05 mg/L in negative milk samples. The assay was also successfully employed to detect melamine in spiked milk samples, with satisfactory recoveries, i.e., between 70.2% and 92.7%.