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The volatile profiles of wheat flour during maturation were examined through headspace solid-phase micro-extraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) combined with electronic nose (E-nose) and electronic tongue (E-tongue) analyses. The wheat flour underwent maturation under three distinct conditions for predetermined durations. While GC/MS coupled with E-tongue exhibited discernment capability among wheat flour samples subjected to varying maturation conditions, E-nose analysis solely relying on principal component analysis failed to achieve discrimination. 83 volatile compounds were identified in wheat flour, with the highest abundance observed in samples matured for 50 d at 25 °C. Notably, trans-2-Nonenal, decanal, and nonanal were the main contributors to the characteristic flavor profile of wheat flour. Integration of HS-SPME-GC/MS with E-tongue indicated superior flavor development and practical viability in wheat flour matured for 50 d at 25 °C. This study furnishes a theoretical groundwork for enhancing the flavor profiles of wheat flour and its derivative products.

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Citrinin (CIT) is a mycotoxin with nephrotoxicity and hepatotoxicity, presenting a significant threat to human health that is often overlooked. Therefore, a dual-signal mode (DPV and SWV) aptasensor for citrinin (CIT) detection was constructed based on tetrahedral DNA nanostructures (TDN) in this study. Furthermore, PtPdCo mesoporous nanozymes exhibit catalase-like catalytic functions, generating significant electrochemical signals through a Fenton-like reaction. Meanwhile their excellent Methylene Blue (MB) loading capability ensures independent dual signal outputs. The RecJf exonuclease-assisted (RecJf Exo-assisted) process can expand the linear detection range, enabling further amplification of the signal. Under optimized conditions, the constructed aptaensor exhibited excellent detection performance with limits of detection (LODs) of 7.67 × 10-3 ng·mL-1 (DPV mode) and 1.57 × 10-3 ng·mL-1 (SWV mode). Due to its multiple signal amplification and highly accurate dual-signal mode detection capability, this aptasensor shows promising potential for the in situ detection.

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The maturation of wheat flour is a transformative process that elevates its processing and culinary attributes to their peak performance levels. Despite extensive research on starch and gluten protein modifications, the impact of lipid changes has been largely unexplored. This study addresses this gap by examining the maturation of freshly milled wheat flour at 15 °C, 25 °C, and 40 °C over 60 days, focusing on enzymatic activities-lipase, lipoxidase, and catalase-and lipid metabolites, including free fatty acids, conjugated trienes, p-anisidine value, and total oxidation value. The results of this study showed that free fatty acids continued to increase at all temperatures, with the most significant increase of 50% at 15 °C. The p-anisidine value followed a pattern of initial increase followed by a decline, while conjugated trienes were markedly higher at 40 °C, suggesting temperature's significant influence on lipid peroxidation. Notably, total oxidation values became erratic post 30 days, indicating a shift in oxidative dynamics. This study underscores the correlation between lipid metabolites and enzymatic activities, revealing the enzymes' pivotal role in lipid oxidation. The interplay of temperature and time offers valuable insights for optimizing wheat flour maturation, ensuring superior quality for various applications.

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Amyloid-like aggregation widely occurs during the processing and production of natural proteins, with evidence indicating its presence following the thermal processing of wheat gluten. However, significant gaps remain in understanding the underlying fibrillation mechanisms and structural polymorphisms. In this study, the amyloid-like aggregation behavior of wheat gluten and its components (glutenin and gliadin) during cooking was systematically analyzed through physicochemical assessment and structural characterization. The presence of amyloid-like fibrils (AFs) was confirmed using X-ray diffraction and Congo red staining, while Thioflavin T fluorescence revealed different patterns and rates of AFs growth among wheat gluten, glutenin, and gliadin. AFs in gliadin exhibited linear growth curves, while those in gluten and glutenin showed S-shaped curves, with the shortest lag phase and fastest growth rate (t1/2 = 2.11 min) observed in glutenin. Molecular weight analyses revealed AFs primarily in the 10-15 kDa range, shifting to higher weights over time. Glutenin-derived AFs had the smallest ζ-potential value (-19.5 mV) and the most significant size increase post cooking (approximately 400 nm). AFs in gluten involve interchain reorganization, hydrophobic interactions, and conformational transitions, leading to additional cross ß-sheets. Atomic force microscopy depicted varying fibril structures during cooking, notably longer, taller, and stiffer AFs from glutenin.

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In the complex Internet of Things (IoT) environment, a plethora of IoT services with akin functions but varying qualities of service exist. To meet diverse customer needs and drive widespread application, service composition optimization becomes crucial. In the current era of rapid development in artificial intelligence, intelligent algorithms play a significant role in optimizing service composition. However, algorithms applied to IoT service composition optimization face common challenges of low search efficiency and insufficient optimization precision, including the Shuffled Frog Leaping Algorithm (SFLA) and Genetic Algorithm (GA). Therefore, this study seeks to enhance the perception of service quality in IoT service composition. It proposes an improved SFLA (ISFLA) based on the original SFLA. The algorithm integrates chaos theory and reverse learning theory for the acquisition of the initial population. It utilizes Euclidean distance to partition the population into groups and employs Gaussian mutation to optimize the optimal individual of each group. Finally, the entire population undergoes evolution through a local update method based on two strategies. Simulated experiments were conducted to search for optimal IoT service composition solutions of different scales. The results indicate that, compared to the SFLA, GA, ISFLA*, IGSFLA and SFLAGA, ISFLA achieves superior fitness values, better composition solutions, and exhibits faster convergence, higher stability, and greater overall operational efficiency.

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This study compared four biocolloids (sanxan, xanthan gum, curdlan, and guar gum) in different concentrations to replace NaCl in improving the recooking quality of salt free frozen cooked noodles (SF-FCNs). Sanxan outperformed NaCl and other biocolloids significantly improving the firmness (21.0%), chewiness (63.5%), and toughness (15.4%) of SF-FCNs after 10 freeze-thaw (FT) cycles. The results of the freezing-thawing curves showed SF-FCNs had prior FT stability when sanxan was added at 1.2%. Subsequently, the result of differential scanning calorimetry and nuclear magnetic resonance revealed sanxan reduced the content and mobility of freezable water while increasing the content of bound water. The scanning electron microscope, mercury intrusion, and optical microscopy analyses indicated that sanxan reduced the size and volume of ice crystals and the structural damage of SF-FCNs by controlling the water. The work contributes to a theoretical framework for enhancing SF-FCNs quality through precise water and ice crystal control.

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In this study, the mechanisms by which sanxan protected the quality of salt-free frozen-cooked noodles (SFFCNs) were investigated, with a focus on the composition and structural properties of gluten. The results showed that sanxan facilitated the formation of glutenin macropolymer and maintained the stabilization of glutenin subunits in freeze-thaw cycles (FTs). In terms of protein structure, sanxan weakened the disruption of secondary structure caused by FTs and increased the proportion of gauche-gauche-gauche (g-g-g) conformations in the disulfide (S-S) bonds bridge conformation. Simultaneously, sanxan reduced the exposure degree of tryptophan (Trp) and tyrosine (Tyr) residues on the protein surface. Moreover, the intermolecular interaction forces indicated that sanxan inhibited S-S bonds breakage and enhanced the intermolecular crosslinking of gluten through ion interactions, which was crucial for improving the stability of gluten. This study provides a more comprehensive theoretical basis for the role of sanxan in improving the quality of SFFCNs.

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The qualities of wheat dough are influenced by the high-molecular-weight glutenin subunits (HMW-GS), a critical component of wheat gluten protein. However, it is still unknown how HMW-GS silencing affects the aggregation characteristics of dough. Two groups of near-isogenic wheat were used to study the effects of HMW-GS silencing on dough aggregation characteristics, dough texture characteristics, and dough microstructure. It was observed that the content of gliadin in LH-11 strain significantly increased compared to the wild-type (WT). Additionally, the amount of glutenin macropolymer and the glutenin/gliadin both decreased. The aggregation characteristics and rheological characteristics of the dough in LH-11 strain were significantly reduced, and the content of ß-sheet in the dough was significantly reduced. The HMW-GS silencing resulted in a reduction in the aggregation of the gluten network in the dough, which related to the alteration of the secondary and microstructure of the gluten.

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Herein, we synthesized anemone-like copper-based metal-organic frameworks (MOFs) loaded with gold-palladium nanoparticles (AuPd@Cu-MOFs) and polyethylenimine-reduced graphene oxide/gold-silver nanosheet composites (PEI-rGO/AuAg NSs) for the first time to construct the sensor and to detect T-2 toxin (T-2) using triple helix molecular switch (THMS) and signal amplification by swing-arm robot. The aptasensor used PEI-rGO/hexagonal AuAg NSs as the electrode modification materials and anemone-like AuPd@Cu-MOFs as the signal materials. The prepared PEI-rGO/hexagonal AuAg NSs had a large specific surface area, excellent electrical conductivity, and good stability, which successfully improved the electrochemical performance of the sensors. The AuPd@Cu-MOFs with high porosity provided a great deal of attachment sites for the signaling molecule thionine (Thi), thereby increasing the signal response. The aptasensor developed in this study demonstrated a remarkable detection limit of 0.054 fg mL-1 under optimized conditions. Furthermore, the successful detection of T-2 in real samples was achieved using the fabricated sensor. The simplicity of the THMS-based method, which entails modifying the aptamer sequence, allows for easy adaptation to different target analytes. Thus, the sensor holds immense potential for applications in quality supervision and food safety.

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With the widespread application of computer technology in engineering education, Online Judge (OJ) systems have become an important platform for programming teaching. OJ systems provide a platform for learners to practice programming skills, submit solutions, and receive feedback. They offer a conducive environment for learners to engage in hands-on coding exercises and enhance their programming abilities. This article explores the use of OJ systems as a software tool for enhancing programming education in engineering. It investigates how the difficulty and order of programming problems affect the users' behavior, performance, and cognitive load in OJ environments. The research data were sourced from Project_CodeNet. Using statistical methods, such as Spearman correlation analysis and differential analysis, the study reveals the factors that influence the users' submission situations, answer order, and learning outcomes. The findings provide useful implications for OJ system developers, teachers, and learners in designing, implementing, and using OJ systems for programming education in engineering. The study suggests that problem difficulty and order should be considered and adjusted according to the users' abilities and progress, to provide appropriate challenges and support, balance the cognitive load, and improve the programming skills of the users.

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Herein, a novel magneto-mediated electrochemical aptasensor using the signal amplification technologies of DNAzyme motor and electrocatalyst for vanilla (VAN) detection was fabricated. The D/B duplex, formed by the DNAzyme motor that was each silenced by a blocker, and hairpin DNA1 (H1) containing adenosine ribonucleotide (rA) site were tethered on the sites of the gold nanoparticles@hollow porphyrinic-Metal-organic framework/polyethyleneimine-reduced graphene oxide (AuHPCN-222/PEI-rGO)-modified gold electrode (AuE). Then, after homogeneous and specific recognition in the presence of the VAN, trigger DNA was released and enriched by magnetic separation technique and introduced to the sensing platform to activate the DNAzyme motor, which efficiently improved target recognition capability and avoided the obstacle of multiple DNA strands tangling. More interestingly, the activated DNAzyme motor could repeatedly bind to and cleave H1 in the presence of Mg2+, leading to the exposure of a plethora of capture probes. The thionine (Thi) functionalized hairpin DNA2 (H2)-Pt@Ni-Co as signal probes could hybridize with capture probes. Additionally, the Pt@Ni-Co electrocatalysts presented catalytic activity towards Thi to obtain stronger electrochemical signals. VAN with concentrations ranging from 1 × 10-6 to 10 µM was determined and a detection limit was down to 0.15 pM. The designed electrochemical sensor was highly selective with specificity, stability, reproducibility, and reliable capability for monitoring the VAN in real samples.

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To clarify the effect of NaCl concentration (0-2.0%) on the formation of amyloid fibrils (AFs) in cooked wheat noodles, the morphology, surface hydrophobicity, secondary structure, molecular weight distribution, microstructure, and crystal structure of AFs were investigated in this paper. Fluorescence data and Congo red stain images confirmed the presence of AFs and revealed that the 0.4% NaCl concentration promoted the production of AFs. The surface hydrophobicity results showed that the hydrophobicity of AFs increased significantly from 3942.05 to 6117.57 when the salt concentration increased from 0 to 0.4%, indicating that hydrophobic interactions were critical for the formation of AFs. Size exclusion chromatography combined with gel electrophoresis plots showed that the effect of NaCl on the molecular weight of AFs was small and mainly distributed in the range of 5-7.1 KDa (equivalent to 40-56 amino acid residues). X-ray diffraction and AFM images showed that the 0.4% NaCl concentration promoted the formation and longitudinal growth of AFs, while higher NaCl concentrations inhibited the formation and expansion of AFs. This study contributes to the understanding of the mechanism of AF formation in wheat flour processing and provides new insight into wheat gluten aggregation behavior.

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Solvent retention capacity (SRC) is a test for the solvation of wheat flour. Its functional contribution was predicted according to the swelling behavior of different diagnostic solvents to different polymeric components of wheat. Ten commercial wheat flour varieties were used as raw materials in this study. The flour quality, gluten aggregation and solvent retention capacity, and their correlations were analyzed. The results showed that protein content, wet gluten content, dry gluten content and the swelling index of glutenin were positively correlated with torque maximum (BEM), torque 15 s before maximum torque (AM), torque 15 s after maximum torque (PM) and gluten aggregation energy (AGGEN). Moreover, they were significantly correlated with the solvent retention capacity. BEM, AM, PM and AGGEN were positively correlated with standard solvent water-SRC (WSRC) and lactic acid-SRC (LASRC). For supplemental solvents, ethanol-SRC (EthSRC) was positively correlated with AGGEN. Sodium dodecyl sulphate-SRC (SDSSRC) was highly correlated with peak maximum time (PMT). Metabisulfite-SRC (MBSSRC) and MBS + SDSSRC were also significantly correlated with BEM, AM, PM and AGGEN sodium metabisulfite. There were significant correlations between gluten aggregation characteristic, standard SRC solvent and supplemental solvent. This study provides a theoretical basis for the evaluation of wheat flour quality.

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BACKGROUND: Ethanol infusion in the vein of Marshall (EI-VOM) has the advantages of reducing the burden of atrial fibrillation (AF), decreasing AF recurrence, and facilitating left pulmonary vein isolation and mitral isthmus bidirectional conduction block. Moreover, it can lead to prominent edema of the coumadin ridge and atrial infarction. Whether these lesions will affect the efficacy and safety of left atrial appendage occlusion (LAAO) has not yet been reported. OBJECTIVES: To explore the clinical outcome of EI-VOM on LAAO during implantation and after 60 days of follow-up. METHODS: A total of 100 consecutive patients who underwent radiofrequency catheter ablation combined with LAAO were enrolled in this study. Patients who also underwent EI-VOM at the same period of LAAO were assigned to group 1 (n = 26), and those who did not undergo EI-VOM were assigned to group 2 (n = 74). The feasibility outcomes included intra-procedural LAAO parameters and follow-up LAAO results involving device-related thrombus, a peri-device leak (PDL), and adequate occlusion (defined as a PDL ≤ 5 mm). Safety outcomes were defined as the composites of severe adverse events and cardiac function. Outpatient follow-up was performed 60 days post-procedure. RESULTS: Intra-procedural LAAO parameters, including the rate of device reselection, rate of device redeployment, rate of intra-procedural PDLs, and total LAAO time, were comparable between groups. Furthermore, intra-procedural adequate occlusion was achieved in all patients. After a median of 68 days, 94 (94.0%) patients received their first radiographic examination. Device-related thrombus was not detected in the follow-up populations. The incidence of follow-up PDLs was similar between the two groups (28.0% vs. 33.3%, p = 0.803). The incidence of adequate occlusion was comparable between groups (96.0% vs. 98.6%, p = 0.463). In group 1, none of the patients experienced severe adverse events. Ethanol infusion significantly reduced the right atrial diameter. CONCLUSIONS: The present study showed that undergoing an EI-VOM procedure did not impact the operation or effectiveness of LAAO. Combining EI-VOM with LAAO was safe and effective.

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Konjac glucomannan (KGM) can act as a food additive to improve the quality of dough. The effects of KGM on the aggregation patterns and structural properties of weak, middle, and strong gluten were studied. We found that with a higher proportion of KGM substitution (10%), the aggregation energy of middle and strong gluten became lower than the control samples, while exceeding the control for weak gluten. With 10% KGM, aggregation of glutenin macropolymer (GMP) was enhanced for weak gluten, but suppressed for middle and strong gluten. The α-helix transferred to ß-sheet in weak, but caused more random-coil structures for middle and strong gluten induced by 10% KGM. With 10% KGM, the network for weak gluten became more continuous, but severely disrupted for middle and strong gluten. Thus, KGM has distinct effects on weak, middle, and strong gluten, which related to the alteration of gluten secondary structures and GMP aggregation pattern.

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The effect and mechanism of sanxan on the quality of salt-free noodles (SFNs) were investigated from different cooking stages (initial stage, 1 min; optimum cooking time, OCT; overcooked time, OT). The results showed significant changes in the cooking process with the addition of 1.2% sanxan. The OCT for noodles with 1.2% sanxan (experimental group, EG) was extended from 5 to 7 min compared to the non-added noodles (blank group, BG) and 1.5% salt-containing noodles (control group, CG). The hardness and adhesiveness of BG, EG, and CG all decreased significantly during cooking. In contrast, the springiness, maximum tensile strength, and tensile fracture distance trended first to increase and then to decrease. At OCT, EG had the highest hardness (3971.69 ± 94.49 g), adhesiveness (372.26 ± 33.56 g s), and maximum tensile strength (41.51 ± 2.76 g), which remained large even after overcooking. However, those in BG and CG showed a significant reduction (p < 0.05). The proportion of free water increased progressively as cooking progressed, with CG showing the largest increase, from 82.29% to 91.19%, whereas EG showed the smallest increase, from 78.34% to 86.02%. During the cooking process, the addition of sanxan delayed the water migration, whereas salt promoted it. Sensory evaluation showed that EG was smoother in appearance than BG and tasted malty with a slight stickiness. Moreover, EG had the smallest k1 and C∞ values. Thus, sanxan is an effective additive to enhance the quality of SFNs and can replace the role of salt in noodles in some properties, which is beneficial for the development of SFNs.

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Self-assembled fibrillation of wheat gluten is a common phenomenon in the daily production and processing of wheat flour products. The driving forces for its formation and the factors that influence the morphology of fibrils have not been thoroughly investigated. In this study, the effect of three bonding changes (breaking hydrogen bonds, strengthening hydrophobic interactions, and SH-SS exchange reactions) on gluten polypeptide (GP) fibrillation was simulated by adjusting the heating temperature (room temperature (RT), 45 °C, 65 °C, and 95 °C). The results showed that the breakage of hydrogen bonds could induce conformational transitions in GPs and help to excite fibrillation in GPs. Strengthened hydrophobic interactions significantly contributed to the fibrillation of GPs. Covalent crosslinks generated by SH-SS exchange reactions might also promote the fibrillation of GPs. GPs with different degrees of hydrolysis (4.0%, 6.0%, and 10.0%, represented by DH 4, DH 6, and DH 10, respectively) presented different extents of fibrillation, with DH 10 GPs having a higher propensity to fibrillation than DH 4 and DH 6 GPs. The results of Fourier's transform infrared spectroscopy indicated that hydrophobic interactions drive the transition from a random coil and α-helix to a ß-sheet. In addition, hydrophobic interactions also drive the intermolecular polymerization of GPs, resulting in larger molecular weight aggregates. The morphology presented by transmission electron microscopy showed that the greater the DH, the stronger the tendency for the worm-like aggregation of GPs.

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Influence of low-sodium salt on water mobility, chemical interactions, and structural changes in noodles was investigated to explore the underlying mechanisms of noodle quality changes, and the results were in comparison with those of NaCl and KCl. Low-sodium salt increased the cooking loss, hardness, chewiness, maximum tensile strength, and tensile fracture distance of noodles. Low-sodium salt enhanced the interaction of water and non-aqueous components in noodles by reducing water mobility. Besides, chemical interaction test showed that low-sodium salt induced the oxidation of some free SH groups to form SS bonds, and strengthened the hydrophobic interaction and hydrogen bonds of gluten. Fluorescence spectra revealed that low-sodium salt changed the microenvironment of gluten molecules. Scanning electron microscopy (SEM) images showed that low-sodium salt noodles presented a more continuous and compact microstructure. Among the three kinds of salted noodles, some qualities of low-sodium salt noodles were equivalent to or slightly worse than those of NaCl noodles, but higher than those of KCl noodles. Hence, replacing part of NaCl with KCl in noodle products is an effective method to reduce sodium content.

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The g-C3N4/CF composite carrier was prepared by ultrasound-assisted maceration and high-temperature calcination. The enzyme immobilization using the g-C3N4/CF as the novel carrier to immobilize lactase and glucose isomerase was enhanced for lactulose production. The carbon fiber (CF) was mixed with melamine powder in the mass ratio of 1:8. The g-C3N4/CF composite carrier was obtained by calcination at 550 °C for 3 h. After the analysis of characteristics, the g-C3N4/CF was successfully composited with the carbon nitride and CF, displaying the improvement of co-immobilization efficiency with the positive effects on the stability of the enzyme. The immobilization efficiency of the co-immobilized enzyme was 37% by the novel carrier of g-C3N4/CF, with the enzyme activity of 13.89 U g-1 at 60 °C. The relative activities of co-immobilized enzymes maintained much more steadily at the wider pH and higher temperature than those of the free dual enzymes, respectively. In the multi-batches of lactulose production, the relative conversion rates in enzymes co-immobilized by the composite carrier were higher than that of the free enzymes during the first four batches, as well as maintaining about a 90% relative conversation rate after the sixth batch. This study provides a novel method for the application of g-C3N4/CF in the field of immobilizing enzymes for the production of lactulose.

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Due to improper storage, the presence of patulin in fruits poses a threat to food safety. Herein, a one-step dual amplification strategy-based electrochemical aptasensor was proposed for patulin detection. Silver-palladium nanoparticles (AgPdNPs) with a hollow and branched structure were used as a supporting material for thionine to provide numerous attachment sites. AuNFs/g-C3N4 was employed as an electrode modification material, which has been demonstrated to facilitate electron transport and improve signal label loading capacity. Ag+ ions were released in the presence of patulin, activating the Ag+-DNAzyme on the electrode surface. The formed Ag+-DNAzymes further cyclically cleaved the substrate DNA, and the released sequences were used as a new trigger to mediate the secondary recirculation. This one-step dual amplification strategy enabled double target recycling without additional procedures. The signal cascade amplification through dual target recycling, was thus available for trace detection of patulin. Under the optimal conditions, the electrochemical aptasensor achieved a satisfactory linear range from 5.0 × 10-6 µg L-1 to 50 µg L-1 with a detection limit of 0.92 fg·mL-1 for the determination of patulin. In addition, the aptasensor exhibited favorable selectivity, reproducibility, repeatability and long-term stability, and thus can be employed for patulin detection in apple juice samples, providing excellent choice for the detection of trace patulin.

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