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Flowering represents the transition from vegetative stage to reproductive stage. As a photoperiod- sensitive crop, soybean can perceive changes in photoperiod to regulate flowering and reproductive periods, thereby influencing soybean yield and other agronomic traits, and determining the photoperiodic adaptability. Therefore, understanding the regulatory mechanisms of photoperiod on flowering and reproductive periods in soybean is one of the hotspots in soybean research. In this review, we introduce the molecular mechanisms of early flowering and early maturation during soybean domestication, and the molecular regulatory pathways of cultivated soybean expansion from the origin to high and low latitudes, respectively. At last, we summarize the research progress on photoperiod adaptability in wild soybean. Analyzing the regulatory mechanisms of photoperiod on soybean life history and domestication will provide valuable insights for the breeding of superior soybean varieties.

Fluoroacetic acid is a highly polar poison used for rodent control. When ingested by the human body, it seriously damages nerve cells and heart tissues and even causes death by cardiac arrest or respiratory failure. Common detection methods for fluoroacetic acid include gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, both of which require complex pretreatment methods, such as derivatization. In this study, a method to determine fluoroacetic acid in human blood and urine based on accelerated solvent extraction-ion chromatography-mass spectrometry (ASE-IC-MS) was established. Two pretreatment methods, namely, acetonitrile precipitation and accelerated solvent extraction, were compared. Furthermore, the effects of different extraction conditions, such as the extraction time, extraction temperature, and number of cycles, were investigated. The most suitable chromatographic separation conditions, such as the chromatographic column, column temperature, and elution procedure, were determined, and the MS conditions, such as the collision energy (CE) and declustering potential (DP) of the ion pairs of the target compound, were investigated. Based on the experimental results, the optimal pretreatment methods and detection conditions were obtained, and reliable data were collected. Deionized water was used as the extraction solvent, and blood and urine samples were processed by accelerated solvent extractor. The supernatant was sequentially collected via centrifugal ultrafiltration and 0.22 μm membrane filtration, diluted 50 times, and then injected into the chromatographic column for detection. An Ion Pac AS20 IC column was used for isocratic elution with 15.0 mmol/L KOH solution as the eluent. The effluent was passed through a suppressor and into a triple quadrupole mass spectrometer, which was used to perform MS/MS (ESI - ) in multiple reaction monitoring (MRM) mode. The quantitative ion was m/z 77.0>57.0 when the CE and DP were -15.0 eV and -20.0 V, respectively. An external standard method was used for quantitative analysis. The results showed a good linear relationship for fluoroacetic acid in the range of 0.5-500.0 μg/L ( r >0.999), with limits of detection (LOD) and quantification (LOQ) of 0.14 and 0.47 μg/L, respectively. The recoveries of fluoroacetic acid in blood and urine were 93.4%-95.8% and 96.2%-98.4%, respectively. The intra-day RSDs for blood and urine were 0.8%-1.6% and 0.2%-1.0%, respectively, while the inter-day RSDs were 2.3%-3.8% and 3.9%-6.9%, respectively. Further investigation revealed that the matrix effects of this method in blood and urine, at -7.4% and -3.0%, respectively, were fairly weak. The established method was successfully applied to detect fluoroacetic acid in human blood and urine obtained from a poisoning case, and the results obtained provided crucial clues that led to swift case resolution. The efficiency of the method was significantly higher than that of conventional detection methods. In conclusion, the developed method has high sensitivity and good repeatability and is suitable for the rapid detection of fluoroacetic acid in human blood and urine. Moreover, because this method does not require derivatization, it is simple and efficient.

Porcine deltacoronavirus (PDCoV) and porcine sapelovirus (PSV) are two viruses that can cause diarrhoea in pigs and bring great economic loss to the pig industry. In this research, a duplex real-time quantitative polymerase chain reaction (qPCR) assay based on SYBR Green I was developed to simultaneously detect PDCoV and PSV. No specific melting peaks were found in other porcine diarrhoea-associated viruses, indicating that the method developed in this study had good specificity. The detection limits of PDCoV and PSV were 1.0 × 10 1  copies μl -1 and 1.0 × 10 2 copies μl -1 , respectively. The duplex real-time qPCR assay tested two hundred and three (203) intestinal and faecal samples collected from diarrhoeal and asymptomatic pigs. The positive rates of PDCoV and PSV were 20.2% and 23.2%, respectively. The co-infection rate of PDCoV and PSV was 13.8%. To evaluate the accuracy of the developed method, conventional PCR and singular TaqMan real-time qPCR assays for PDCoV/PSV were also used to detect the samples. The results showed that the duplex real-time qPCR assay was consistent with the singular assays, but its sensitivity was higher than conventional PCR methods. This duplex real-time qPCR assay provides a rapid, sensitive and reliable method in a clinic to simultaneously detect PDCoV and PSV., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2023 Lu et al.)

Taking the sewage and drinking water treatment system of two cities in Zhejiang Province as the main research target, a systematic investigation on the common artificial sweeteners was carried out by solid phase extraction-high performance liquid chromatography (SPE-HPLC). The results showed that SPE-HPLC can accurately determine micro acesulfame (ACE), saccharin (SAC), aspartame (ASP), and neotame (NEO) in water. The detection limits were 57, 120, 170, and 47 μg·L -1 , and the quantification limits were 190, 400, 567, and 157 μg·L -1 , respectively. After optimization of the solid phase extraction procedure when using PWAX columns, the recoveries of ACE and SAC were enhanced to 86.5% and 97.7%; however, it slightly decreased to 66.5% for NEO. The occurrence rates of ACE, SAC, and NEO in domestic sewage were 100.0%, and it was only 33.3% for ASP. The highest concentrations of four aforementioned artificial sweeteners in domestic sewage were 0.83, 4.52, 1.22, and 7.57 μg·L -1 , respectively. The highest concentrations of acesulfame, saccharin, aspartame, and neotame in source water were 22.94, 39.17, 0.73, and 8.92 μg·L -1 , respectively, and detection rates were 72.7%, 90.9%, 18.2%, and 90.9%, respectively. Most artificial sweeteners were removed by the prozone process; the removal efficiencies of ACE, SAC, and NEO ranged from 67.7% to 100.0%, and the removal efficiencies of ACE, SAC, and NEO by the advanced treatment process ranged from 73.7% to 100.0%, which effectively reduced the risk of drinking water quality. The four artificial sweeteners were not detected in the water supply network.