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[Objective] To improve the drying quality of pumpkins. [Methods] This study conducted experiments on hot air drying, vacuum drying, and combined hot air-vacuum drying, these drying characteristics were evaluated and compared based on unit energy consumption, rehydration ratio, and color difference indicators. Combining BP neural network model with genetic algorithm, combined with entropy weight and weighted scoring method, a multi-objective comprehensive optimization was carried out for the combined hot air-vacuum drying of pumpkins. [Results] Under the same conditions, the highest drying efficiency was hot air drying; And the findings revealed that at drying temperatures was 55 ℃, with a moisture content transition point of 30%, the combined drying method reduced the drying time by 52.63%, compared to vacuum drying. The lowest unit energy consumption was vacuum drying; The worst rehydration performance was hot air drying. The best color was vacuum drying. The optimal drying parameters determined by the genetic algorithm combined with a BP neural network model were a hot air drying temperature of 65 ℃, conversion point moisture content of 50%, and vacuum drying temperature of 56.050 9 ℃. Verification experiments demonstrated that the average relative errors between the genetic algorithm optimized values and the experimental values for unit energy consumption, rehydration ratio, and color difference were 2.5%, 5.53%, and 4.84%, respectively, all lower than 6%. [Conclusion] The combined hot air-vacuum drying of pumpkin integrates the advantages of both hot air drying and vacuum drying, and combined with BP neural network genetic algorithm model can optimize the process parameters for pumpkin hot air vacuum drying.

Identifying key road segments and prioritizing their protection to enhance the resilience of road networks against crisis events remains a pressing issue. In this paper, complex network theory is adopted to determine the importance ranking of road segments and analyse how to select the road segments that need to be rehabilitated in the case of insufficient budget. This study will provide three different methods to assess the importance of road segments, and with the help of user equilibrium model for traffic demand allocation, calculate the system travel time after rehabilitation to evaluate, compare, and analyse different rehabilitation schemes, and then get the rehabilitation scheme with better performance. Meanwhile, it is investigated whether the optimal road segment rehabilitation combination will change under different budget levels. The results of the case study finally show that the rehabilitation set determined by the Clustering Coefficient and the betweenness is better, which can provide practical guidance on how to select the prioritized rehabilitation segments.

A flapping foil, which mimics the flapping wings of birds and the locomotion of aquatic organisms, is an alternative to a conventional turbine for the harvesting of renewable energy from ubiquitous flows in the atmosphere, oceans, and rivers. In this work, the energy harvesting performance of flapping foils with attached flaps at the trailing edge is numerically studied by using an immersed boundary–lattice Boltzmann method (IB-LBM) at a Reynolds number of 1100. Three different configurations are considered, namely, a clean NACA0015 foil, a NACA0015 foil with a single flap, and a NACA0015 foil with two symmetric flaps. The results show that the flap attached to the trailing edge is able to enhance the energy harvesting efficiency, and the two symmetric flaps can achieve more enhancements than its single-flap counterpart. The mechanism of such enhancements is attributed the separation of the interactions of vortexes generated at the upper and bottom surfaces of the foil. To further obtain the optimal configurations of the two symmetric flaps, the angle between the two flaps (α) and the length ( l f ) of the flap are systematically studied. The results show that the optimal energy harvesting performance is achieved at α = 60 ∘ and l f = 0.1 c (c denotes the chord length of the foil). Compared with the baseline case, namely, the clean NACA foil, the optimal configuration can achieve an improvement of efficiency up to 19.94%. This study presents a strategy by adding two symmetric flaps at the trailing edge of the foil to enhance the energy harvesting performance of a flapping foil, which contributes to advancing the development of simple and efficient clean energy harvesting by using a flapping foil. [ABSTRACT FROM AUTHOR]

Chiral N-aryl-alpha amino acids feature core structures that serve as the backbone of several agents with synthetic and medical value. Analysis of a coupling reaction of aryl halides with alpha-amino acids showed that CuI alone can already catalyze the reaction, which makes the palladium agent unecessary. The reaction yields the new protein kinase C activator benzolactam-V8. In addition, the presence of an accelerating effect caused by the alpha-amino acid structure is established for the reaction.

To locate all local optimum of the black box function, such as the simulation function, a method based on fitness landscape analysis is proposed. Firstly, the fitness distance correlation (FDC) is modified according to the characteristics of our problem, and the relationship between the modified FDC and the roughness grade of the fitness landscape is explored. Based on the relationship, an FDC based repeated spitt region method (FRsR) is designed to breakdown the whose feastbee region into several acceptable sub-region according to the FDC value, and a certain number of initial search points are assigned in each sub-region based on the FDC value of the sub-region, followed by an optimization procedure using the pattern search algorithm. Experimental results show that the proposed method can locate all local optimum with feuer initial points, and comparison study shows that it performs better than traditional methods, such as the uniformly generating initial points method and other known methods, both in speed and in quality of the solution. [ABSTRACT FROM AUTHOR]

The social force model is widely used in the field of pedestrian modeling and simulation. However, it can only be applied to simple scenarios. When there are many obstacles in the environment, and the pedestrian cannot see the goal, the model will lead to problems such as obstacle penetrating and trajectory oscillation. We proposed a hybrid model composed of tactical layer and operation layer. The core concept of the tactical layer is detour point. We constructed a computational geometry method to find the detour point based on the criterion of shortest path, and solved the multiple occlusion problem. Then we designed a progressive route planning algorithm to guild pedestrian's movement. Finally, a simulation system is developed to verify the proposed model. The simulation results show that, both in single obstacle and multiple obstacle environments, pedestrian can avoid the obstacles naturally and the trajectory is realistic and reasonable. [ABSTRACT FROM AUTHOR]

Background: Hypotension is a risk factor for postoperative complications, but evidence from randomized trials does not support that a higher blood pressure target always leads to optimized outcomes. The heterogeneity of underlying hemodynamics during hypotension may contribute to these contradictory results. Exploring the subtypes of hypotension can enable optimal management of intraoperative hypotension., Methods: This is a prospective, observational pilot study. Patients who were ≥ 45 years old and scheduled to undergo moderate-to-high-risk noncardiac surgery were enrolled in this study. The primary objective of this pilot study was to investigate the frequency and distribution of perioperative hypotension and its subtypes (hypotension with or without cardiac output reduction). The exposure of hypotension and its subtypes in patients with and without myocardial or acute kidney injury were also explored., Results: Sixty patients were included in the analysis. 83% (50/60) of the patients experienced perioperative hypotension. The median duration of hypotension for each patient was 8.0 [interquartile range, 3.1-23.3] minutes. Reduced cardiac output was present during 77% of the hypotension duration. Patients suffering from postoperative myocardial or acute kidney injury displayed longer duration and more extensive exposure in all hypotension subtypes. However, the percentage of different hypotension subtypes did not differ in patients with or without postoperative myocardial or acute kidney injury., Conclusion: Perioperative hypotension was frequently accompanied by cardiac output reduction in moderate-to-high-risk noncardiac surgical patients. However, due to the pilot nature of this study, the relationship between hypotension subtypes and postoperative myocardial or acute kidney injury still needs further exploration., Clinical Trial Registration: https://www.chictr.org.cn/showprojEN.html?proj=134260, CTR2200055929., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Zhang, Kou, Wang, He, Wen, Chen, Song, Wu, Huang and Huang.)

[60]Fullerene reacted with various beta-dicarbonyl compounds in the presence of Mn(OAc)3*2H2O to generate dihydrofuran-fused [60]fullerene derivatives or 1,4-bisadducts. Dihydrofuran-fused [60]fullerene derivatives 2 could be formed by treatment of alpha-unsubstituted beta-diketones 1a-e or beta-ketoesters 1f and 1g with [60]fullerene in refluxing chlorobenzene in the presence of Mn(III). Solvent-participated unsymmetrical 1,4-bisadducts 3 were obtained through the reaction of [60]fullerene with dimethyl malonate 1h or alpha-substituted beta-dicarbonyl compounds 1i-1n in toluene. A possible reaction mechanism for the formation of different fullerene derivatives is proposed.