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Target tracking is a core working mode of airborne photoelectric reconnaissance and aiming system, and its performance directly determines the mission efficiency of the airborne system. Aiming at the outstanding problems and technical difficulties in the application of target tracking, according to the multi-sensor configuration and application characteristics of the system, an intelligent target tracking strategy based on inertial measurement and video image information fusion is proposed, which integrates multi-dimensional information such as inertial navigation, motion mea-surement, servo control, geography and image coordinates. Simulation analysis and flight test show that the strategy can effectively improve the anti-jamming performance of target tracking, realize the robust and persistent target tracking in full dynamic complex scenes, and improve the combat ability of reconnaissance and surveillance, target positioning, weapon guidance of the airborne system.

Morphing wing is one of the important development directions of future aircraft design, and the study of in-plane deformation of the morphing wing surface has received widespread attention. In this paper, four aspects in-cluding variable span length, variable sweep angle, variable chord length and combined deformation are analyzed to describe the current status of domestic and international research on in-plane morphing wings, summarize the defor-mation mechanism and its advantages and disadvantages, and analyze the future development trend of morphing wing. In view of the current research situation and the application requirements of the morphing wing, the key tech-nologies of the morphing wing are proposed, including the morphing skin technology, morphing mechanism, intelli-gent actuator, sensor and control network. The application requirements of each key technology and the existing problems are analyzed furthermore. The future development direction is summarized, which can provide some references for the design and application realization of in-plane morphing wings.

Background The Self-rated Fall Risk Questionnaire (FRQ) developed by the US CDC is one of the few questionnaires applied for fall risk self-assessment in community-dwelling older adults, which is thought to be simple and highly applicable. The Modified Falls Efficacy Scale (MFES) is also widely used in the fall risk assessment in older adults. Thus the comparison between the Self-rated FRQ and MFES in identifying fall risk in older adults would be meaningful. Objective To explore the applicability of the Chinese version of Self-rated FRQ (FRQ-C) in assessing the fall risks in community-dwelling older Chinese adults by comparing it with the Chinese version of MFES (MFES-C) . Methods A total of 203 seniors above 65 who received physical examination services, treatment services, or vaccination services from the community health center were selected by use of convenience sampling and invited to attend a survey for understanding their demographics, and fall risk rated by the MFES-C and the Self-rated FRQ-C. ROC analysis was conducted to assess the performance (sensitivity, specificity, positive and negative predictive values) of the Self-rated FRQ-C and MFES-C in the prediction of having at least one or two falls in the past year. Results Fifty-eight (28.6%) of them fell once or more in the past year. The mean score of the Self-rated FRQ-C for the fall group was higher than that of the non-fall group with a statistically significant difference (P0.05) . Those with high fall risk assessed by the Self-rated FRQ-C (≥4 points) had higher prevalence of fall (P0.05) . The AUC values in identifying having one or more falls in the past year for the Self-rated FRQ-C and MFES-C were 0.74〔95%CI (0.68, 0.81) 〕 and 0.59〔95%CI (0.50, 0.68) 〕. When identifying having two or more falls in the past year, the AUC value of the Self-rated FRQ-C increased to 0.80〔95%CI (0.70, 0.90) 〕, and that of the MFES-C increased to 0.65〔95%CI (0.52, 0.78) 〕. The sensitivity and specificity of the Self-rated FRQ-C with a threshold of 4 points were 81.0% and 51.7%, respectively, and those of the MFES-C with a threshold of 112 points were 53.5% and 60.0%, respectively. Conclusion Compared with the MFES-C, the Self-rated FRQ-C may have higher sensitivity in identifying fall risk in older adults with higher operability and applicability in community settings.

Considering that the existing path planning algorithms for mobile robots under rugged terrain do not consider the ground flatness and the lack of optimality, which leads to the instability of the center of mass of the mobile robot, this paper proposes an improved A* algorithm for mobile robots under rugged terrain based on the ground accessibility model and the ground ruggedness model. Firstly, the ground accessibility and ruggedness models are established based on the elevation map, expressing the ground flatness. Secondly, the elevation cost function that can obtain the optimal path is designed based on the two types of models combined with the characteristics of the A* algorithm, and the continuous cost function is established by connecting with the original distance cost function, which avoids the center-of-mass instability caused by the non-optimal path. Finally, the effectiveness of the improved algorithm is verified by simulation and experiment. The results show that compared with the existing commonly used path planning algorithms under rugged terrain, the enhanced algorithm improves the smoothness of paths and the optimization degree of paths in the path planning process under rough terrain. [ABSTRACT FROM AUTHOR]

The application of a diammonium phosphate coating effectively mitigates direct contact between the phosphate fertilizer and the soil, thus minimizing phosphorus fixation. Humic acid holds a pivotal role in augmenting soil quality and activating the soil's phosphorus reserves. Notably, when combined with humic acid, diammonium phosphate significantly enhances the utilization efficiency of phosphate fertilizer. However, there is a paucity of literature exploring the dynamics of nutrient transport in soil when humic acid is paired with coated phosphate fertilizers. To assess the impact of the combined application of coated diammonium phosphate and humic acid on wheat yield enhancement, we conducted pot experiments along with leaching and ammonia volatilization simulation tests, aiming to elucidate the effects of this combination on nutrient transport. The study explored the effects of three distinct treatments: coated diammonium phosphate (CP), coated diammonium phosphate combined with humic acid (PHA), and coated diammonium phosphate combined with humic acid (CPHA). The investigation focused on analyzing their impacts on wheat yield, ammonia volatilization, soil-available phosphorus, nitrate nitrogen, ammonium nitrogen, soil-available potassium, as well as the mobilization and transport of calcium and magnesium in the soil. (1) Compared to the P treatment, the PHA and CP treatments significantly increased grain yield by 17.2% and 13.5%, respectively. The PHA treatment also increased effective panicle number by 12.9%. Overall, the CP, PHA, and CPHA treatments improved grain yield by 13.5%, 17.2%, and 19.1% compared to the P treatment. (2) The CP and PHA treatments reduced available phosphorus by 95.6% and 49.2%, calcium by 2.0% and 67.0%, and magnesium by 11.6% and 46.1% compared to the P treatment. Ammonium nitrogen decreased by 37.0% and 64.3%, while nitrate nitrogen increased by 14.0% in CP and slightly decreased by 0.8% in PHA. In the leaching solution, PHA and CP treatments reduced available phosphorus by 96.7% and 62.5%, increased calcium by 5.0% and 78.9%, decreased ammonium nitrogen by 2.2% and 43.4%, and decreased nitrate nitrogen by 10.6% and 13.0%. The PHA and CPHA treatments increased available phosphorus in the 0–20 cm soil layer by 1.4 times and 25.8%, respectively. (3) The CP treatment reduced ammonia volatilization by 87.0% compared to the P treatment, while the CPHA treatment further reduced it by 87.5% compared to the PHA treatment. The application of coated diammonium phosphate efficiently delays nutrient release and reduces nutrient leaching in the soil. Additionally, the integration of humic acid significantly improves the availability of phosphorus in the soil, minimizing phosphorus loss. Notably, the combined application of humic acid and coated diammonium phosphate leads to a significant increase in soil phosphorus content, subsequently enhancing soil nutrient availability, conserving fertilizer, and ultimately resulting in an improved wheat yield. [ABSTRACT FROM AUTHOR]

Introduction: Combined allergic rhinitis and asthma syndrome (CARAS) is a concurrent allergic symptom of diseases of allergic rhinitis and asthma. However, the mechanism of CARAS remains unclear. The study aimed to investigate the impact of microRNA-21 (miR-21) on CARAS via targeting poly (ADP-ribose) polymerase-1 (PARP-1) and phosphoinositide 3-kinase (PI3K)/AKT pathways. Methods: The levels of miR-21-5p and PARP-1 in CARAS patients were detected by quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). An ovalbumin-sensitized mouse model of CARAS was established. And knock down of miR-21-5p was constructed by intranasally administering with miR-21-5p shRNA-encoding adeno-associated virus vector. Airway resistance and airway inflammatory response were detected. ELISA was used to evaluate IL-4/IL-5/IL-13 levels in bronchoalveolar lavage fluid (BALF). Expression levels of E-cadherin, fibronectin, and α-SMA were determined using Western blotting. The levels of PARP-1 and the activation of PI3K/AKT were assayed. Results: Downregulation of miR-21-5p relieved pathophysiological symptoms of asthma including airway hyperreactivity and inflammatory cell infiltration. Downregulation of miR-21-5p significantly reduced the levels of IL4, IL-5, and IL-13 in BALF. Additionally, downregulation of miR-21-5p inhibited the epithelial-mesenchymal transition (EMT) process in CARAS mice. Furthermore, miR-21-5p regulated PARP-1 and was involved in PI3K/AKT activation in CARAS mice. Conclusion: Downregulation of miR-21-5p ameliorated CARAS-associated lung injury by alleviating airway inflammation, inhibiting the EMT process, and regulating PARP-1/PI3K/AKT in a mouse model of CARAS. [ABSTRACT FROM AUTHOR]