Polyethyleneimine-Sulfur Quantum Dot Composites for Dual-Channel Detection of Tetracycline by Colorimetric and Fluorescence Sensing

The residue of tetracycline from food and environment poses a potential threat to public health. Developing a more convenient portable optical detection system has become more demanding than fluorescence detection. This study describes a sensor of sulfur quantum dots (SQDs) with a positively charged passivator for tetracycline in the concentrations from 0.20 to 100 μM and a limit of detection of 0.15 μM (3σ/k). A new optical sensing device was also designed with a smartphone as the detector for sensing the color change from blue to yellow-green upon the addition of tetracycline. In the presence of Eu3+, the detectable color change is extended to red. The verification of the sensing device was applied to the real detection of lake water and milk, with a standard recovery from 93.1 to 109%. This emissive excitation-independent SQD first ensures a sensitive and accurate analysis at very low concentrations and also demonstrates evident color changes upon interaction with tetracycline. The application of this method has provided great convenience for practical detection

Application of Molecular Simulation Methods in Food Science: Status and Prospects

Molecular simulation methods, such as molecular docking, molecular dynamic (MD) simulation, and quantum chemical (QC) calculation, have become popular as characterization and/or virtual screening tools because they can visually display interaction details that in vitro experiments can not capture and quickly screen bioactive compounds from large databases with millions of molecules. Currently, interdisciplinary research has expanded molecular simulation technology from computer aided drug design (CADD) to food science. More food scientists are supporting their hypotheses/results with this technology. To understand better the use of molecular simulation methods, it is necessary to systematically summarize the latest applications and usage trends of molecular simulation methods in the research field of food science. However, this type of review article is rare. To bridge this gap, we have comprehensively summarized the principle, combination usage, and application of molecular simulation methods in food science. We also analyzed the limitations and future trends and offered valuable strategies with the latest technologies to help food scientists use molecular simulation methods

Physics-Based Neural Network as Constitutive Law for Finite Element Analysis of Sintering

In the sintering of advanced ceramics, a digital twin consisted of a finite element model can predict the final shape and microstructure of a sintered ceramic. However, to minimise uncertainties, it is essential to continually update the mechanical properties in the digital twin using data collected from the manufacturing process. One promising approach for achieving this is through artificial neural networks (ANN). This study introduces a machine learning strategy to update the constitutive behaviour of advanced ceramics in finite element analysis of sintering deformation. A major challenge in implementing machine learning in material processing is the huge amount of data required by the training and validation of an ANN, which are often unavailable or incomplete in a real manufacturing process. This study demonstrates that the data requirement can be reduced by employing a two-step training technique. Firstly, the ANN is trained using a nonlinear constitutive law, which describes a general relationship between the strain rates and stresses. Subsequently, the weights and biases of the ANN are transferred for the retraining using limited experimental data for an actual ceramic. It is shown that such approach can successfully capture the nonlinear constitutive behaviour of fine-grained alumina without demanding for large amount of experimental data. A case study is provided, highlighting the feasibility of implementing the ANN in a commercial finite element package, to replace the constitutive law and predict the shrinkage and distortion of a sintering part. In particular, the sintered dumb-bell shape part, simulated using the retrained ANN, showed grain size and relative density that markedly different from those using the nonlinear constitutive law. It is important to note that the proposed methodology is generic and can be used to create ANNs to replace constitutive laws in finite element analysis in digital twins for a wide range of other engineering processes.</p

Transcriptome-microRNA analysis of <i>Sarcoptes scabiei</i> and host immune response

<div><p>Scabies is a parasitic disease, caused by the mite <i>Sarcoptes scabiei</i>, and is considered one of the top 50 epidemic diseases and one the most common human skin disease, worldwide. Allergic dermatitis, including an intense itch, is a common symptom, however diagnosis is difficult and there is currently no effective vaccine. The goal of this study was to examine the immune interaction mechanism of both <i>S</i>. <i>scabiei</i> and infected hosts. mRNA-seq and microRNA-seq were conducted on the <i>S</i>. <i>scabiei</i> mite and on infected and uninfected hosts. We focused on differential expression of unigenes and microRNAs, as well as the real targets of unigenes in enriched immune signaling pathways. <i>S</i>. <i>scabiei</i> enhanced host immune function and decreased metabolism after infection, while the immune response of the host inhibited <i>S</i>. <i>scabiei</i> proliferation and metabolism signaling pathways. Differentially expressed unigenes of <i>S</i>. <i>scabiei</i> were enriched in the JAK-STAT signaling pathway and the Toll-like receptor signaling pathway. The differential expression analysis indicated that microRNAs of <i>S</i>. <i>scabiei</i> and hosts have major roles in regulating immune interactions between parasites and hosts.</p></div

Distribution of the number of unigenes and read length in <i>S</i>.<i>scabiei</i> samples.

<p>Distribution of the number of unigenes and read length in <i>S</i>.<i>scabiei</i> samples.</p

RT-PCR validation of the differentially expressed unigenes and microRNAs from Illumina sequencing.

<p>The relative expression levels of toll like receptor signaling pathway related unigenes and immune signaling pathways related microRNAs were determined by RT-PCR using cDNA as template.</p

Y(IO₃)₃ as a Novel Photocatalyst: Synthesis, Characterization, and Highly Efficient Photocatalytic Activity

Nonbonding layer-structured Y­(IO₃)₃ was successfully prepared by a simple hydrothermal route and investigated as a novel photocatalyst for the first time. Its crystal structure was characterized by X-ray diffraction, high-resolution transmission electron microscopy, and scanning electron microscopy. The optical absorption edge and band gap of Y­(IO₃)₃ have been determined by UV–vis diffuse reflectance spectra. Theoretical calculations of the electronic structure of Y­(IO₃)₃ confirmed its direct optical transition property near the absorption edge region, and the orbital components of the conduction band and valence band (VB) were also analyzed. The photocatalytic performance of Y­(IO₃)₃ was evaluated by photooxidative decomposition of rhodamine B under ultraviolet light irradiation. It demonstrated that Y­(IO₃)₃ exhibits highly efficient photocatalytic activity, which is much better than those of commercial TiO₂ (P25) and important UV photocatalysts BiOCl and BiIO₄. The origin of the excellent photocatalytic performance of Y­(IO₃)₃ was investigated by electron spin resonance and terephthalic acid photoluminescence techniques. The results revealed that the highly strong photooxidation ability that resulted from its very positive VB position should be responsible for the excellent photocatalytic performance

The immune pathways—Related microRNA of <i>Sarcoptes scabiei</i>.

<p>The immune pathways—Related microRNA of <i>Sarcoptes scabiei</i>.</p

ReBe₂B₅O₁₁ (Re = Y, Gd): Rare-Earth Beryllium Borates as Deep-Ultraviolet Nonlinear-Optical Materials

Two novel rare-earth beryllium borates <i>Re</i>Be₂B₅O₁₁ (<i>Re</i> = Y, Gd) have been discovered. These materials possess a unique structural feature with a platelike infinite _∞²[Be₂B₅O₁₁]^3– superlayer, which is first found in beryllium borates. The superlayer can be seen as sandwich-shaped with _∞¹[B₄O₈]^4– chains linking up with a _∞²[Be₂BO₅]^3– sublayer above and below via the B–O–Be bond. Each _∞²[Be₂B₅O₁₁]^3– layer is further connected to the neighboring layer through <i>Re</i>³⁺ cations coordinating with O atoms. Both of these two crystals have very short cutoff wavelengths below 200 nm and exhibit relatively large nonlinear-optical (NLO) effects, indicating their promising applications as good deep-UV NLO crystals

Additional file 19: Table S16. of Preliminary analysis of Psoroptes ovis transcriptome in different developmental stages

Allergen genes which did not result in Blast hits with genes from other mites or ticks among the downregulated DEGs. (XLSX 16 kb