Identification of key sensory and chemical factors determining flavor quality of Xinyu mandarin during ripening and storage.

Xinyu mandarin is popular for its good flavor, but its flavor deteriorates during postharvest storage. To better understand the underlying basis of this change, the dynamics of the sensory profiles were investigated throughout fruit ripening and storage. Sweetness and sourness, determined especially by sucrose and citric acid content, were identified as the key sensory factors in flavor establishment during ripening, but not in flavor deterioration during storage. Postharvest flavor deterioration is mainly attributed to the reduction of retronasal aroma and the development of off-flavor. Furthermore, sugars, acids and volatile compounds were analyzed. Among the 101 detected volatile compounds, 10 changed significantly during the ripening process. The concentrations of 15 volatile components decreased during late postharvest storage, among which α-pinene and d-limonene were likely to play key roles in the reduction of aroma. Three volatile compounds were found to increase during storage, associated with off-flavor development.

Over 10% Efficient Sb2 (S,Se)3 Solar Cells Enabled by CsI-Doping Strategy.

Antimony selenosulfide (Sb2 (S,Se)3 ) is an emerging quasi-1D photovoltaic semiconductor with exceptional photoelectric properties. The low-symmetry chain structure contains complex defects and makes it difficult to improve electrical properties via doping method. This article reports a doping strategy to enhance the efficiency of Sb2 (S,Se)3 solar cells by using alkali halide (CsI) as the hydrothermal reaction precursor. It is found that the Cs and I ions are effectively doped and atomically coordinate with Sb ions and S/Se ions. The CsI-doping Sb2 (S,Se)3 absorbers exhibit enhanced grain morphologies and reduced trap densities. The consequential CsI-doping Sb2 (S,Se)3 based solar cells demonstrate favorable band alignment, suppressed carrier recombination, and improved device performance. An efficiency as high as 10.05% under standard AM1.5 illumination irradiance is achieved. This precursor-based alkali halide doping strategy provides a useful guidance for high-efficiency antimony selenosulfide solar cells.

Exosome­delivered miR­486­3p inhibits the progression of osteosarcoma via sponging CircKEAP1/MARCH1 axis components.

Accumulating evidence shows that the disruption of competing endogenous RNA (ceRNA) networks plays a significant role in osteosarcoma (OS) initiation and progression. However, the specific roles and functions of the ceRNAs in OS remain unclear. First, differentially expressed microRNAs (DEMs) were identified by mining the E-MTAB-1136 and GSE28423 datasets. MiRWalk website was used to predict the target gene of miRNA. OS-associated circular RNA (circRNA) expression profiles were downloaded from the published microarray databases. Gene expression levels were assessed through reverse transcription-quantitative PCR and western blotting. The biological effects of circKEAP1, microRNA (miR)-486-3p and membrane-associated RINGCH finger protein 1 (MARCH1) in OS cells were investigated using Cell Counting Kit-8, Transwell, colony formation and wound healing assays. miR-486-3p was aberrantly downregulated in OS tissues and cell lines and was packed with exosomes. miR-486-3p overexpression was shown to inhibit OS cell progression and promoted cell cycle arrest in vitro. In addition, MARCH1 was identified as a direct downstream molecule of miR-486-3p in OS cells. circKEAP1 was found to be upregulated in OS tissues and cells. circKEAP1 was found to have binding sites with miR-486-3p. Mechanistically, circKEAP1 positively regulated MARCH1 expression by sponging miR-486-3p. Exosomal miR-486-3p inhibited the progression of OS by sponging the circKEAP1/MARCH1 axis. These findings may provide a promising treatment approach for OS.

Cold acclimation alleviates photosynthetic inhibition and oxidative damage induced by cold stress in citrus seedlings.

Cold stress seriously inhibits plant growth and development, geographical distribution, and yield stability of plants. Cold acclimation (CA) is an important strategy for modulating cold stress, but the mechanism by which CA induces plant resistance to cold stress is still not clear. The purpose of this study was to investigate the effect of CA treatment on the cold resistance of citrus seedlings under cold stress treatment, and to use seedlings without CA treatment as the control (NA). The results revealed that CA treatment increased the content of photosynthetic pigments under cold stress, whereas cold stress greatly reduced the value of gas exchange parameters. CA treatment also promoted the activity of Rubisco and FBPase, as well as led to an upregulation of the transcription levels of photosynthetic related genes (rbcL and rbcS)，compared to the NA group without cold stress. In addition, cold stress profoundly reduced photochemical chemistry of photosystem II (PSII), especially the maximum quantum efficiency (Fv/Fm) in PSII. Conversely, CA treatment improved the chlorophyll a fluorescence parameters, thereby improving electron transfer efficiency. Moreover, under cold stress, CA treatment alleviated oxidative stress damage to cell membranes by inhibiting the concentration of H2O2 and MDA, enhancing the activities of superoxide dismutase (SOD), catalase (CAT), ascorbic acid peroxidase (APX) and glutathione reductase (GR), accompanied by an increase in the expression level of antioxidant enzyme genes (CuZnSOD1, CAT1, APX and GR). Additionally, CA also increased the contents of abscisic acid (ABA) and salicylic acid (SA) in plants under cold stress. Overall, we concluded that CA treatment suppressed the negative effects of cold stress by enhancing photosynthetic performance, antioxidant enzymes functions and plant hormones contents.

Nanophotonic inverse design with deep neural networks based on knowledge transfer using imbalanced datasets.

Deep neural networks (DNNs) have been used as a new method for nanophotonic inverse design. However, DNNs need a huge dataset to train if we need to select materials from the material library for the inverse design. This puts the DNN method into a dilemma of poor performance with a small training dataset or loss of the advantage of short design time, for collecting a large amount of data is time consuming. In this work, we propose a multi-scenario training method for the DNN model using imbalanced datasets. The imbalanced datasets used by our method is nearly four times smaller compared with other training methods. We believe that as the material library increases, the advantages of the imbalanced datasets will become more obvious. Using the high-precision predictive DNN model obtained by this new method, different multilayer nanoparticles and multilayer nanofilms have been designed with a hybrid optimization algorithm combining genetic algorithm and gradient descent optimization algorithm. The advantage of our method is that it can freely select discrete materials from the material library and simultaneously find the inverse design of discrete material type and continuous structural parameters of the nanophotonic devices.

Depicting the molecular responses of adventitious rooting to waterlogging in melon hypocotyls by transcriptome profiling.

Waterlogging is a severe abiotic stressor that inhibits crop growth and productivity owing to the decline in the amount of oxygen available to the waterlogged organs. Although melon (Cucumis melo L.) is sensitive to waterlogging, its ability to form adventitious roots facilitates the diffusion of oxygen and allows the plant to survive waterlogging. To provide comprehensive insight into the adventitious rooting in response to waterlogging of melon, global transcriptome changes during this process were investigated. Of the 17,146 genes expressed during waterlogging, 7363 of them were differentially expressed in the pairwise comparisons between different waterlogging treatment time points. A further analysis suggested that the genes involved in sugar cleavage, glycolysis, fermentation, reactive oxygen species scavenging, cell wall modification, cell cycle governing, microtubule remodeling, hormone signals and transcription factors could play crucial roles in the adventitious root production induced by waterlogging. Additionally, ethylene and ERFs were found to be vital factors that function in melon during adventitious rooting. This study broadens our understanding of the mechanisms that underlie adventitious rooting induced by waterlogging and lays the theoretical foundation for further molecular breeding of waterlogging-tolerant melon. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02866-w.

Sodium tanshinone IIA sulfonate prevents radiation-induced damage in primary rat cardiac fibroblasts.

This study investigated the effects of X-ray irradiation on primary rat cardiac fibroblasts (CFs) and its potential mechanism, as well as whether sodium tanshinone IIA sulfonate (STS) has protective effect on CFs and its possible mechanism. Our data demonstrated that X-rays inhibited cell growth and increased oxidative stress in CFs, and STS mitigated X-ray-induced injury. Enzyme-linked immuno-sorbent assay showed that X-rays increased the levels of secreted angiotensin II (Ang II) and brain natriuretic peptide (BNP). STS inhibited the X-ray-induced increases in Ang II and BNP release. Apoptosis and cell cycle of CFs were analyzed using flow cytometry. X-rays induced apoptosis in CFs, whereas STS inhibited apoptosis in CFs after X-ray irradiation. X-rays induced S-phase cell cycle arrest in CFs, which could be reversed by STS. X-rays increased the expression of phosphorylated-P38/P38, cleaved caspase-3 and caspase-3 as well as decreased the expression of phosphorylated extracellular signal-regulated kinase 1/2 (ERK 1/2)/ERK 1/2 and B cell lymphoma 2 (Bcl-2)/Bcl-2 associated X protein (BAX) in CFs, as shown by Western blotting. STS mitigated the X-ray radiation-induced expression changes of these proteins. In conclusion, our results demonstrated that STS may potentially be developed as a medical countermeasure to mitigate radiation-induced cardiac damage.

A simple way to synthesize large-scale Cu2O/Ag nanoflowers for ultrasensitive surface-enhanced Raman scattering detection.

Here, we report a simple strategy to prepare highly sensitive surface-enhanced Raman spectroscopy (SERS) substrates based on Ag decorated Cu2O nanoparticles by combining two common techniques, viz, thermal oxidation growth of Cu2O nanoparticles and magnetron sputtering fabrication of a Ag nanoparticle film. Methylene blue is used as the Raman analyte for the SERS study, and the substrates fabricated under optimized conditions have very good sensitivity (analytical enhancement factor ∼108), stability, and reproducibility. A linear dependence of the SERS intensities with the concentration was obtained with an R 2 value >0.9. These excellent properties indicate that the substrate has great potential in the detection of biological and chemical substances.