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【Objective】 Crops are vulnerable to drought and waterlogging at their seedling stages. Experience-based irrigation and drainage is not effective to alleviate water stresses that seedlings could face. This paper presents an automatic drainage and irrigation system we developed for seedlings of direct-seeded rice. 【Method】 The system includes a micro-sprinkler irrigation system and an automatic drainage device. They are controlled by a LoRa wireless communication network; the irrigation - drainage scheduling was calculated by the fuzzy control algorithm, based on the dynamics of soil moisture and growth of the seedlings measured in the field. The applicability of the system in the fields was evaluated using performance indicators and drainage device performance indicators. 【Result】 ① In the terms of performance, the delay in the response of the system was 0.398 s, the decision-making time was 1.348 s, and the errors of the information monitoring was ±1.48%. ② The automatic drainage device took 4-6 s to close or open, and the standby electric current was 21.7 mA. ③ Experimental results showed that the systems can control soil moisture at 85% of the field capacity 15 days after the seed-drilling; the survival rate of the seedlings was 83.9%. 【Conclusion】 The automatic irrigation and drainage system for seedlings of direct-drilled rice is energy-efficient. It can maintain soil moisture in the proximity of the soil surface around the designed value, alleviating water stress and improving the survival of the seedlings of the directly drilled rice.

The dynamic characteristics of shale gas flow directly affect the high-efficiency exploitation of shale gas, which has attracted widespread attention. In this study, the flow rate and permeability of gas (methane and helium) under variable confining stress and gas pressure conditions were carried out based on six shale samples from the Upper Ordovician Wufeng Formation and the Lower Silurian Longmaxi Formation in the southeastern Sichuan basin. By performing the seepage experiments of non-adsorbed gas (helium) and adsorbed gas (methane) under the same test conditions, the controls of gas slippage, matrix shrinkage and effective stress on the methane permeability change during the flow process were quantitatively decoupled. It is concluded that the methane permeability change is the result of the superposition of three major geological effects including gas slippage, matrix shrinkage and effective stress. During the gas pressure depletion, the effective stress effect is the main factor leading to the permeability decrease, while the gas slippage is the main factor causing the permeability increase. The permeability change caused by matrix shrinkage is more complex, and is closely related to the shale composition. Based on the control mechanism of permeability change, a prediction model of the methane permeability change in Chinese marine shales is proposed and has a good match with experimental data. The model is suitable for the process of gas pressure reduction under a constant confining stress condition. This research is helpful to understand the characteristic and mechanism of dynamic flow process of shale gas.

At present, research on aerial spraying operations with UAVs mainly focuses on the deposition outcomes of droplets, with insufficient depth in the exploration of the movement process of droplet deposition. The movement characteristics of droplet deposition as the most fundamental factors affecting the effectiveness of pesticide application by UAVs are of great significance for improving droplet deposition. This study takes flat spray nozzles as the research object, uses the Particle Image Velocimetry (PIV) technique to obtain movement data of water droplet deposition under the influence of rotor flow fields, and investigates the variation characteristics of droplet deposition speed under different influencing factors. The results show that the deposition speed and the distribution area of high-speed (>12 m/s) particles increase with the increase of rotor speed, spraying pressure, and nozzle size. When the rotor speed increases from 0 r/min to 1800 r/min, the average increase in maximum droplet deposition speed for nozzle models LU120-02, LU120-03 and LU120-04 is 33.26%, 19.02%, and 7.62%, respectively. The rotor flow field significantly increases the number of high-speed droplets, making the dispersed droplet velocity distribution more concentrated. When the rotor speed is 0, 1000, 1500, and 1800 r/min, the average decay rates of droplet deposition speed are 36.72%, 20.00%, 15.47%, and 13.21%, respectively, indicating that the rotor flow field helps to reduce the decrease in droplet deposition speed, enabling droplets to deposit on the target area at a higher speed, reducing drift risk and evaporation loss. This study's results are beneficial for revealing the mechanism of droplet deposition movement in aerial spraying by plant protection UAVs, improving the understanding of droplet movement, and providing data support and guidance for precise spraying operations. [ABSTRACT FROM AUTHOR]

The concentration data of semi‐volatile n‐alkanes and PAHs in the gas phase and in PM2.5 were obtained from Nanjing and Denver. First, the gas‐particle partitioning coefficients of the target compounds were calculated and compared with the predictions based on the equilibrium absorptive partitioning theory. Although the vapor pressure (poL) estimation method was selected to improve the agreement between measured and predicted partitioning coefficients, n‐alkanes in Denver and PAHs in both cities exhibited stronger sorption to PM2.5 than predicted. By including the adsorption mechanism, the average logarithms and temporal variations of the partitioning coefficients were well simulated in both Nanjing and Denver. The partitioning of n‐alkanes in Nanjing can be primarily explained by the absorption mechanism, while the adsorption mechanism dominates that for n‐alkanes in Denver and PAHs in both cities. To obtain an optimal simulation, the poL of n‐alkanes and PAHs was estimated using the SPARC and SIMPOL—two group contribution methods, respectively, and the difference between desorption and vaporization enthalpies was set between 2 and 3 kcal mol−1 for n‐alkanes in Denver and PAHs in both cities. Therefore, the estimation of poL and surface adsorption should be carefully considered when parameterizing the gas‐particle partitioning of non‐polar organic compounds in future field and modeling studies. Plain Language Summary: The gas‐particle partitioning of semi‐volatile organic compounds is an important atmospheric process that can affect their fate and transport. The concentrations of selected n‐alkanes and PAHs significantly present in both the gas and particulate phases in Nanjing and Denver were obtained from our previous studies. When absorption in particulate organic matter (OM) was assumed as the dominant mechanism, the gas‐particle partitioning of n‐alkanes in Denver and PAHs in both cities cannot be well explained. When both absorption in the particulate OM phase and surface adsorption were considered, good agreement between measured and predicted partitioning coefficients could be obtained for all target compounds by selecting an appropriate method to estimate the vapor pressure (poL) and fixing the difference between desorption and vaporization enthalpies. In previous studies, the simulated partitioning coefficients differed by orders of magnitude from the measured values, partly due to the ignorance of poL estimation method selection and surface adsorption. Key Points: n‐Alkanes and PAHs can show stronger sorption to particulate matter (PM) than in the simulation based on the equilibrium absorptive partitioning theoryCombining absorption and adsorption mechanisms can improve the agreement between measured and predicted partitioning coefficientsThe sorption of n‐alkanes and PAHs on PM is less liquid‐like in Denver than in Nanjing [ABSTRACT FROM AUTHOR]

To explore the effect of pesticide-adjuvants mixture on the control efficacy against Rice Chilo Suppressalis(walker). This study designed a three-factor, three-level orthogonal experiments with pesticides (10% emamectin benzoate·indoxacard SC, 5% chlorantraniliprole SC and 0.8% rotenone SC), adjuvants(organosilicon, lecithin and mineral Oil) , spray volume (21,24 and 27 L/hm2), referred to the three-factor, three-level orthogonal experimental scheme. And made the blank factor the deviation to analyze its rationality. Analysis of variance (ANOVA) statistical method was used to analyze the significance level of each factor. Duncan's new multiple range test (DMRT) method was used to analyze the order of the influence of different levels of each factor on the control efficacy against Rice Chilo Suppressalis(walker). The results showed that, under the experiment conditions of this research, the mean square value of the deviation factor was smaller than the mean square value of the pesticides, the adjuvants and the spray volume, and the deviation of the orthogonal experiment was within a reasonable range. The main order of the effect of the three factors on the control efficacy of Rice Chilo Suppressalis(walker) was: adjuvants > pesticides > spray volumn. On the 14th day after spraying, pesticides showed a significant effect on the control efficacy (P Chlorantraniliprole > Emamectin Benzoate·Indoxacard. The level 1 of the factor "adjuvants" was more effective, in the order of Organosilicon > Lecithin > Mineral Oil. The level 3 of the factor "spray volume" was more effective, in the order of 27 L/hm2 > 24 L/hm2 > 21 L/hm2. Therefore, a preferred pesticide-adjuvants mixture method was 0.8% rotenone SC, organosilicon adjuvants and 27 L/hm² of spray volume, which had a rapid and long-lasting control efficacy, and its control efficacy in the field reached 81.45% on the 14th day after spraying. Additionally, there was also a satisfactory pesticide-adjuvants mixture method that was 5% Chlorantraniliprole, organosilicon adjuvants and 24 L/hm² of spray volume. This mixture method also performed well, achieving 79.3% control efficacy in the field on the 14th day after spraying. This study could provide a reference for the optimization of the mixture methods of solutions (pesticides, adjuvants and spray volume) for controlling Rice Chilo Suppressalis(walker).

Background and Objective: Prevention of periodontal bone resorption triggered by Porphyromonas gingivalis (P. gingivalis) is crucial for dental stability. Capsaicin, known as the pungent ingredient of chili peppers, can activate key signaling molecules involved in osteogenic process. However, the effect of capsaicin on osteogenesis of periodontal ligament stem cells (PDLSCs) under inflammation remains elusive. Methods: P. gingivalis culture suspension was added to mimic the inflammatory status after capsaicin pretreatment. The effects of capsaicin on the osteogenesis of PDLSCs, as well as mitochondrial morphology, Ca2+ level, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and osteogenesis‐regulated protein expression levels were analyzed. Furthermore, a mouse experimental periodontitis model was established to evaluate the effect of capsaicin on alveolar bone resorption and the expression of osteogenesis‐related proteins. Results: Under P. gingivalis stimulation, capsaicin increased osteogenesis of PDLSCs. Not surprisingly, capsaicin rescued the damage to mitochondrial morphology, decreased the concentration of intracellular Ca2+ and ROS, enhanced MMP and activated phosphatidylinositol 3‐kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. The in vivo results showed that capsaicin significantly attenuated alveolar bone loss and augmented the expression of bone associated proteins. Conclusion: Capsaicin increases osteogenesis of PDLSCs under inflammation and reduces alveolar bone resorption in mouse experimental periodontitis. [ABSTRACT FROM AUTHOR]

Actinomycetes have long been recognized as important sources of clinical antibiotics. However, the exploration of rare actinomycetes, despite their potential for producing bioactive molecules, has remained relatively limited compared to the extensively studied Streptomyces genus. The extensive investigation of Streptomyces species and their natural products has led to a diminished probability of discovering novel bioactive compounds from this group. Consequently, our research focus has shifted towards less explored actinomycetes, beyond Streptomyces, with particular emphasis on Kitasatospora setae (K. setae). The genome of K. setae was annotated and analyzed through whole-genome sequencing using multiple bio-informatics tools, revealing an 8.6 Mbp genome with a 74.42% G + C content. AntiSMASH analysis identified 40 putative biosynthetic gene clusters (BGCs), approximately half of which were recessive and unknown. Additionally, metabolomic mining utilizing mass spectrometry demonstrated the potential for this rare actinomycete to generate numerous bioactive compounds such as glycosides and macrolides, with bafilomycin being the major compound produced. Collectively, genomics- and metabolomics-based techniques confirmed K. setae's potential as a bioactive secondary metabolite producer that is worthy of further exploration. [ABSTRACT FROM AUTHOR]