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• Nanobody-based dual-mode immunoassay for Ara h 3 was developed with LOD of 6.61 ng/mL. • The dominance of nanobody and B/ N -CDs improved the accuracy of Ara h 3 immunoassay. • The method achieved the assessment of Ara h 3 in peanut contamination foodstuffs. To improve the performance of peanut allergen Ara h 3 detection, depending on boron and nitrogen carbon dots (B/ N -CDs), a nanobody (Nb) mediated dual-mode immunoassay was established, which combines the dominance of colorimetry with ratiometric fluorescence techniques. With the catalysis of Horseradish peroxidase (HRP), the oxidization of o-phenylenediamine (o-PD) in the presence of H 2 O 2 , leading to the production of yellow 2,3-diaminophenolazine (DAP) with an absorption peak at 431 nm. Owing to inner filter effect (IFE), DAP quenched the fluorescence of B/ N -CDs at 426 nm, and it emerged a new emission peak at 549 nm. The fluorescence intensity ratio and absorption intensity can be utilized for quantitative analysis of Ara h 3 concentration. Under optimal conditions, the detection limits were 6.61 and 9.79 ng·mL−1, respectively. The dual-mode immunoassay was assessed containing specificity, stability, reproducibility, and practicability. This method paved the way for sensitive detection of Ara h 3 without background Interference. [ABSTRACT FROM AUTHOR]

• Our generator is a weighted fractional space-time Brownian field. • And it's not a backward martingale. • The existence, uniqueness and explicit solution pair for Y and Z. • Some kind of sharp Hlder continuity for the solution is obtained. • The Feynman-Kac Formula is established. This paper is concerned with the backward stochastic differential equations whose generator is a weighted fractional Brownian field: Y t = ξ + ∫ t T Y s W (d s , B s) − ∫ t T Z s d B s , 0 ≤ t ≤ T , where W is a (d + 1) -parameter weighted fractional Brownian field of Hurst parameter H = (H 0 , H 1 , ⋯ , H d) , which provide probabilistic interpretations (Feynman-Kac formulas) for certain linear stochastic partial differential equations with colored space-time noise. Conditions on the Hurst parameter H and on the decay rate of the weight are given to ensure the existence and uniqueness of the solution pair. Moreover, the explicit expression for both components Y and Z of the solution pair is given. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effect of EGCG on macrophage polarization has been thoroughly confirmed. • The suppression of M1 polarization after EGCG treatment was observed. • The promotion of M2 macrophages after EGCG treatment has been confirmed. The intervention of EGCG on M1/M2 macrophage polarization was still unclear and should be studied comprehensively. In this context, the intervention of EGCG on macrophage polarization has been investigated to reveal that EGCG promoted M2 polarization of RAW264.7 upon treating with EGCG. A significant inhibitory effect of EGCG on M1 polarization was observed upon stimulating with LPS and IFN-γ. The expression of macrophage phenotype related marker genes (iNOS, COX-2, IL-1β for M1; Arg-1, Ym-1, IL-10 for M2) demonstrated the suppression of M1 polarization and the promotion of M2 polarization in liver, colon, spleen, and brain. Further analysis against peritoneal macrophages verified the increased M2 phenotypes and decreased M1 macrophages, and the similar variation in liver were confirmed by immunohistochemistry (IHC). No significant variation of spleen macrophages was observed with the general macrophages in declined tendency. Bio-distribution of EGCG and its metabolites (EGC, GA) in different organs has been further determined. [ABSTRACT FROM AUTHOR]

• The first report ever on nanobodies directed against intact S. aureus. • A Nb-mediated immuno-assay avoids false-positive detection of S. aureus. • Development of a sensitive sandwich ELISA against S. aureus. • The potential application to detect intact S. aureus in food matrix. The interaction between conventional immunoglobulins (Igs) and the Ig-binding surface proteins of Staphylococcus aureus (S. aureus) have obstructed the development of immuno-assays to detect these bacteria. The current study aimed to select nanobodies (Nbs) recognizing specifically S. aureus and to establish an immuno-assay to uncover S. aureus contaminations in foods. An alpaca was immunized with an inactivated S. aureus strain followed by the construction of a Nb library from which four target-specific Nbs were retrieved. Subsequently, a sandwich ELISA employing the Nb147 and biotinylated-Nb147 pair to capture and to detect S. aureus , respectively, was established to possess a detection limit of 1.4 × 105 colony forming units (CFU)/mL. The dedicated immuno-assay has been verified by detecting 10 CFU/mL of S. aureus in milk samples after an 8 h-enrichment step. This study provides the basis of an easy, reproducible and effective immuno-assay to screen for S. aureus contaminations in foods. [ABSTRACT FROM AUTHOR]

This paper investigates the finite termination of the optimal solution sequence in parametric optimization as a subproblem of the equilibrium problems. By introducing an augmented mapping on the solution set of the equilibrium problems, we establish the concept of augmented weak sharpness for this set relative to the sequence of optimal solutions in parametric optimization. Augmented weak sharpness is an extension of the concepts of weak sharpness and strongly non-degeneracy. Under the condition that the solution set of the equilibrium problems is augmented weak sharpness, sufficient conditions for the finite termination of the sequence of optimal solutions in parametric optimization are provided. For some special cases of the equilibrium problems (Mathematical Programming (MP), Variational Inequality Problems (VIP), etc.), these results extend the corresponding results under weak sharpness or strongly non-degeneracy conditions in the existing literature. Additionally, they also provide weaker sufficient conditions for the finite termination of many optimization algorithms. [ABSTRACT FROM AUTHOR]

• Cold green tea beverage contained considerable catechins, gallic acid and theanine. • Cold green tea beverage could significantly prevent obesity. • The anti-obesity effects might be attributed to the stimulation of serum peptide YY (PYY) secretion. • Cold green tea beverage could modulate some specific bacteria. This study was designed to explore the anti-obesity effects of cold-water brewed green tea (CWB-GT) on high-fat diet (HFD)-fed mice. CWB-GT was prepared by brewing tea leaves with 30 ℃ cold water, which contained considerable active ingredients including catechins, gallic acid and theanine. Our data demonstrated that CWB-GT could significantly ameliorate obesity and modulate gut microbiota composition of HFD-fed mice by affecting some specific bacteria. Besides, the expression of lipogenesis-related genes including FAS, HMGR and SREBP-1c in liver was inhibited and the expression of fatty acid oxidation-related genes including PPARα and PGC-1α in adipose tissue was enhanced. These benefits might be attributed to the stimulation of serum peptide YY (PYY) secretion. In particular, specific bacteria modulated by CWB-GT including Lachnospiraceae bacterium DW67, Blautia coccoides, Parabacteroides merdae and Bacteroides_vulgatus might be key mediators in exerting anti-obesity effects. This study suggested that CWB-GT could represent a novel functional low-calorie beverage. [ABSTRACT FROM AUTHOR]

The interaction between diet and gut microbiota plays a critical role in human health. While the conventional in vitro models cannot faithfully recapitulate the intestinal microenvironment including multicellular architectures dynamic, tissue-tissue interfaces, flow, and shear force, which have limited the investigations on interactions between diet components and the gut. Microfluidic chip-based technology promises to overcome the limitations of conventional models by recapitulating tissue- and organ-level physiology and function. This review focuses on summarizing the advances of gut-on-a-chip technologies and their applications for clarifying the interplay mechanisms between diet, microbiota, and host health. Model construction and major components, as well as applications of various models, are summarized and discussed. Gut-on-a-chip could be used as a very promising tool for the evaluation of bioactive components, as well as novel food product development. • The gut-on-a-chip technology has emerged as a very promising in vitro tool. • Deep insight into the diet-microbiota-host crosstalk is possible with the technology. • The advances in the construction of the gut-on-a-chip models are summarized. • The advantages of five classified models are discussed for food nutrition research. [ABSTRACT FROM AUTHOR]

• Water soluble red fluorescent carbon dots had BSA-enhanced fluorescence property. • Fluorescence-wavelength dual-readout POCT was established for detecting BSA. • The carbon dots had hydroxyl radicals-dependent fluorescence quenching property. • Nanobody based fluorescent-photothermal dual-readout immunosensor was established. • The tandem with POCT and immunosensor enable simultaneous detecting BSA and β-LG. Two carbon dots (CDs) (λ Em = 525 nm, G-CDs and λ Em = 640 nm, R-CDs) were synthesized from citric acid and urea. The bovine serum albumin (BSA) responsiveness of the R-CDs was used to develop a "fluorescence-wavelength" label-free point of care testing (POCT) for the detection of the milk quality marker BSA with the detection limit (LOD) of 4.89 μg/mL for fluorescence mode and 3.38 μg/mL for wavelength mode. In addition, R-CDs were found to have hydroxyl radical (·OH)-dependent fluorescence quenching properties, and a "fluorescence-photothermal" immunosensor based on nanobodies was constructed by introducing the fluorescence signal of R-CDs@BSA and the photothermal signal of oxTMB for the detection of β-lactoglobulin (β-LG) with the LOD of 0.034 ng/mL for fluorescence mode and 0.075 ng/mL for photothermal mode. The tandem detection of POCT and immunosensor enables the simultaneous and highly sensitive detection of BSA and β-LG after only simple dilution of less than 5 µL of sample. [ABSTRACT FROM AUTHOR]

In this paper, we study the exact asymptotic separation rate of two distinct solutions of doubly singular stochastic Volterra integral equations (SVIEs) with two different initial values. The main tool is the Gronwall inequality with doubly singular kernel. For a special linear singular SVIEs, we obtain a bound for the leading coefficient of the asymptotic separation rate for the two distinct solutions which reveals that our asymptotic results are sharp. [ABSTRACT FROM AUTHOR]

• Identified the thermal degradation products of creatinine. • Revealed the role of creatinine thermal degradation product in the formation of PhIP. • Verified the radical pathway of PhIP formation by DFT calculations. Creatinine, commonly found in muscle tissue, has been demonstrated as an essential precursor of 2-amino-1-methyl-6-phenylimidazo [4, 5- b ] pyridine (PhIP) in thermally possessed foods. In this current study, formamide and N -methylformamide were identified as the main thermal degradation products of creatinine. The raised production of PhIP and the decreased level of aldol condensation product occurred simultaneously with the increased addition of formamide in the model system of creatinine and phenylacetaldehyde. It was demonstrated that formamide reacted with the aldol condensation product to close the pyridine ring to form PhIP. The radical pathway of PhIP formation was then proposed and verified by density functional theory (DFT) computation and an ion-trap time-of-flight mass spectrometer (IT-TOF-MS). This is the first report of the role of the creatinine thermal degradation product in the pathway of PhIP formation, which could facilitate potential strategies against the inhibition of PhIP formation in thermally processed foods. [ABSTRACT FROM AUTHOR]

• Nanobody-based sandwich ELISA (sELISA) was constructed for detecting β-LG with the LOD of 0.24 ng/mL. • sELISA achieved effectively discrimination of pasteurized milk and UHT milk. • sELISA achieved the assessment of milk or β-LG content in milk-containing and milk-free beverages. The problems of inaccurate detection values of thermal-processed β-lactoglobulin (β-LG) content seriously affect the screening of allergens. A monoclonal antibody (mAb) against β-LG was successfully prepared and a highly sensitive sandwich ELISA (sELISA) was constructed with specific nanobody (Nb) as the capture antibody with detection limit of 0.24 ng/mL. Based on this sELISA, the ability of Nb and mAb to recognize β-LG and β-LG interacting with milk components was explored. Combined with protein structure analysis to elaborate the mechanism of shielding β-LG antigen epitopes during thermal-processing, thus enabling the differentiation between pasteurized and ultra-high temperature sterilized milk, the detection of milk content in milk-containing beverages, and the highly sensitive detection and analysis of β-LG allergens in dairy-free products. The method provides methodological support for identifying the quality of dairy products and reducing the risk of β-LG contamination in dairy-free products. [ABSTRACT FROM AUTHOR]