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Using data from Yushu Agricultural Meteorological Station of Jilin from 2018 to 2023, the impact of different sowing dates of corn is investigated focusing on its growth and yield composition as well as grain quality under global warming. It is also debated whether adjusting the sowing date of corn could be a measure for agriculture to adapt to climate change. Results show that the utilization efficiency of accumulated temperature during the growing season of corn varies with different sowing dates. The accumulated temperature is the highest in the first sowing date and lowest in the fourth sowing date, with an average decrease of 8.3% compared to the first sowing date. Different sowing dates of corn have an impact on the growing period. The duration of the first sowing date for corn is extended by an average of 7.5 days compared to the normal sowing date, while durations of the third and fourth sowing dates are shortened by 5.7 days and 13.8 days, respectively. Different sowing dates have an impact on the yield structure of corn. In the first sowing date, there is an increase in the weight of 100 grains of corn in 2 years during 6 years, while a decrease by 4.8% and 8.7% in the third and fourth sowing dates compared to the normal sowing date. The average number of grains per plant in the first sowing date increases by 0.2%, while decreases by 6.0% and 9.3% in the third and fourth sowing date. Overall, delaying the corn sowing date by 10 days and 20 days results in an average yield reduction of 10.9% and 17.1%. Sowing corn 10 days earlier could increase the yield in some years. The change in sowing dates has little effect on the quality of grains. Therefore, an early corn sowing date can be utilized as a strategy to adapt to climate change in certain regions of Northeast China.

Objective： A new method was developed for the simultaneous determination of three kinds of ochratoxins in coffee by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) combined with QuEChERS pretreatment. Methods： Samples were extracted by acetonitri-water-formic acid solution (55∶40∶5) with ultrasonic, salted out with a QuEChERS salt pocket, and then purified with a (ZanChERS-Myco17) column. The chromatographic separation was performed on an ACQUITY UPLC BEH C18 (1.7 μm, 2.1 mm×100 mm) column by gradient elution using a mobile phase comprising 0.2% formic acid aqueous solution and acetonitrile. In the positive ion mode of electric spray, the samples detected were used by multiple reaction monitoring (MRM) modes with internal standard method. Results： Three target substances had a good linear relationship in the range of 0.1~20.0 ng/mL, and the correlation coefficient was greater than 0.999 46. The detection limit and quantitative limit were 0.1~0.2 μg/kg and 0.2~0.7 μg/kg, respectively. Average recoveries at three spiked levels in the coffee matrix were 79.0%~103.3% with a relative standard deviation of 1.5%~7.6%. Conclusion： This method has the advantages of simple sample pretreatment, good reproducibility and high efficiency, and is suitable for the high-throughput detection of multiple ochratoxins in different coffee samples.

Objective: This study aimed to establish a method for the simultaneous determination of 16 quinolones in freshwater fish by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and then analyze the effect of three different cooking methods (by boiling, steaming and frying) on the residues of quinolone antibiotics. Methods: Samples were ultrasonic extracted with acetonitrile (with 4% formic acid) and purified with C18 solid phase extraction column. The chromatographic separation was performed on a Waters ACQUITY UPLC BEH C18 (1.7 μm, 2.1 mm×100 mm) column, with 0.1% formic acid water-acetonitrile as mobile phase for gradient elution. Mass spectrometry (ESI+) was monitored by multiple reaction ions and quantified by internal standard method. Results: 16 quinolones showed a clear linear relationship between 2.0 ng/mL and 50 ng/mL, and the correlation coefficient was greater than 0.998 49. The limits of detection quantification were 0.3~4.1 μg/kg and 0.9~11.0 μg/kg, respectively. Average recoveries in matrices at low, medium, and high spiked levels ranged from 79.0% to 104.7%, with a standard deviation of 1.0% to 8.1%. There was no significant difference in the residues of 16 quinolones between the fish meat-positive samples of three different cooking methods and the control. Conclusion: The method was simple, rapid, and sensitive, and met the high-throughput screening and dietary risk assessment of quinolone antibiotics in freshwater fish.

As an emerging isoxazoline insecticide, afoxolaner has a good effect in the prevention and treatment of canine parasite infections. During the crystallization process of afoxolaner, inconsistent crystal phases and thermal properties are observed in the same batch of samples. In this work, the solubility and crystallization process were studied, and the best method was found to be slow evaporation in ethanol. The results showed that the crystal phase was highly consistent. The average peak value of DSC was observed at 149.6 ± 0.6 °C, with a relative mean deviation of only 0.4%. Furthermore, the isolation of needle-like single crystals allowed for the determination of the crystal structure, revealing the enantiomeric pairs of afoxolaner co-crystallized with water in a monoclinic crystal system belonging to the centrosymmetric space group P21/n. It is hoped that this study will provide important insights into the crystallographic data of afoxolaner for its practical applications. [ABSTRACT FROM AUTHOR]

To address the issue of regional water resource scarcity, water diversion projects have been constructed worldwide. As an essential lifeline project, the prefabricated aqueduct is prevalently utilized in cross-regional water transfer and diversion projects. This paper was based on the prefabricated aqueduct project, which adopted fabricated technologies including the connection technology among the gravity pier, the prefabricated arch ribs, and the prefabricated bent frame columns. The PHC piles, bearing platforms, bent frame columns, arch ribs, and groove bodies were all prefabricated components that were transported to the site for installation. The connections of the prefabricated aqueduct employed to link different components were of such crucial significance that their safety and stability determined whether the overall structure would be compromised. Therefore, the main objective of this paper was to examine the stress and deformation of this prefabricated aqueduct to prevent the occurrence of security risks throughout the entire construction stage. The finite element model was established in Midas Civil, and the entire construction stage was simulated and analyzed. Coupled with on-site monitoring, the stress and deformation of the prefabricated aqueduct were evaluated. The results indicated that the tensile stress, the compressive stress, the vertical displacement, and the lateral displacement of each part of the prefabricated aqueduct met the requirements of the standard, suggesting that the overall structure with the applied connection technology was in a safe and stable state throughout the entire construction stage. [ABSTRACT FROM AUTHOR]

The variability of stratospheric water vapor (SWV) plays a crucial role in stratospheric chemistry and Earth's energy budget, strongly influenced by sea surface temperature (SST). In this study, we systematically investigate the response of lower-SWV (LSWV) to regional sea surface temperature changes using idealized SST patch experiments within a climate model. The results indicate that LSWV is most sensitive to tropical sea surface temperature, with the strongest response occurring in late autumn and early winter. Warming of the tropical Indian Ocean and western Pacific (WP) leads to stratospheric drying, while warming of the tropical Atlantic (TA) and eastern Pacific results in stratospheric moistening. The drying impact on LSWV due to warming in the western Pacific Ocean exceeds the wet effect in the eastern Pacific Ocean by approximately 60%. The variations in tropical SST influence LSWV by modulating the temperature at the tropical tropopause layer, especially over the Indo-Pacific warm pool through Matsuno–Gill responses. Furthermore, the response of LSWV to tropical SST changes exhibits nonnegligible nonlinearity, which indicates the importance of nonlinearity in determining the LSWV response to global surface warming. Significance Statement: In this study, we explore how changes in the temperature of the ocean's surface can affect the amount of water vapor in the stratosphere, a layer of Earth's atmosphere. Understanding this relationship is important because water vapor in the stratosphere can influence both our climate and the chemistry of the atmosphere. Using a climate model, we found that water vapor in the lower stratosphere is especially responsive to temperature changes in tropical ocean regions. Specifically, when the Indian Ocean and the western Pacific get warmer, the stratosphere tends to get drier. On the other hand, warming in the Atlantic and eastern Pacific leads to more moisture in the stratosphere. The way these changes add up is complex and not simply a sum of individual parts, especially in tropical warm pool regions. Our findings have implications for how we understand and predict the impacts of climate change on stratospheric water vapor. [ABSTRACT FROM AUTHOR]

A high-throughput method based on UPLC-MS/MS was developed for the determination of 44 mycotoxins in longan and its products. The samples were extracted with 80% acetonitrile-water (V/V) solution containing 1% acetic acid, and purified by PSA and C18. A Waters ACQUITY UPLC BEH C18 column was used for separation, with 0.2% FA-acetonitrile and water-acetonitrile as the mobile phase for gradient elution. Quantification was performed using the internal standard method under MRM mode with positive and negative electropry ionization. Results showed that a good linear relationship was found for the 44 mycotoxins, with the correlation coefficients ≥0.990 41, the limit of detection ranging within 0.003~0.7 µg/kg, and the limit of quantification being 0.01~2.0 µg/kg. The relative standard deviation (RSD) was 0.7%~9.7% (n=6), and the recoveries of the 44 mycotoxins at three spiking levels (low, intermediate and high levels) ranging within 70.7%~123.6%. The analyses of the 17 batches of longan and its products purchased from market revealed that the positive rate was 100%, with the concentrations of mycotoxins like 15-ADON, Fus X, PAT, TeA were relatively higher, indicating that they were the main contaminated mycotoxins during the growth, storage and processing processes of longan. Hazard Quotient (HQ) was used to assess the dietary exposure risk The assessment results showed that the HQ values of 21 mycotoxins were 0~0.012 37, which were all lower than 1, indicating no risk and little threat to human health. [ABSTRACT FROM AUTHOR]

The traditional safety protection measures for railway crossings can no longer meet the current development needs due to their low efficiency, high cost and potential safety hazards. To meet this challenge, this paper proposes an innovative intelligent centralized control system based on wireless communication for early warning of railway crossings, which aims to guarantee the life and property safety of the staff and traffic participants at railway crossings. The LoRa long-range radiofrequency communication technology, OpenMV-based vehicle and pedestrian target recognition technology and computer based interlocking technology are combined to design a low-power, easy-to-deploy remote centralized management system for unattended railway crossings, which can improve the efficiency of railway operation, and enhance the safety of railway transport. [ABSTRACT FROM AUTHOR]