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We investigated the changes of gel characteristics and structure of ultrasonically treated corn starch during freeze-thaw cycles, with a view to providing theoretical guidance for improving the quality of quick-frozen starch-based foods. The effects of the number of freeze-thaw cycles on the dynamic rheological and textural properties of ultrasonically modified corn starch gels were analyzed and their structures were characterized by using a rheometer, a texture analyzer, a low-field nuclear magnetic resonance (NMR) spectrometer, a Fourier transform infrared (FTIR) spectrometer and an X-ray diffractometer (XRD). The results showed that compared with native corn starch, the water separation rate of ultrasonically modified corn starch gels significantly decreased by 5.19% (P < 0.05) at the 4th freeze-thaw cycle, indicating improved freeze-thaw stability; the storage modulus and loss modulus of ultrasonically modified corn starch gels decreased, and the gel strength was weaker; the hardness significantly decreased by 10.83% (P < 0.05), and the amylose content decreased 0.15%. Moreover, the iodine binding force was weakened, the transverse relaxation time distribution curve was shifted to the left, the short-range ordered structure was weakened, and the relative crystallinity was reduced. The gel properties and the structural characterization results indicate that ultrasonic treatment can inhibit water migration and double helix structure formation in the corn starch gel system during freeze-thaw cycles and consequently improve its freeze-thaw stability.

Background As the main providers of essential pediatric services, the capabilities of community general practitioners (GPs) in managing pediatric patients may directly reflects the overall status of pediatric care services in primary care settings. In China, there are great regional differences in the supply and demand of pediatric services, and the capabilities of primary care settings are unsatisfactory in providing pediatric services. The current encounters and influencing factors of GPs with pediatric patients in suburban districts are worthy of attention. Objective To understand the status and associated factors of clinical encounters of GPs with pediatric patients in a suburban district of Beijing, providing a reference for the development of tiered diagnosis and treatment of pediatric diseases. Methods In June 2021, purposive sampling was used to recruit GPs who participated in a training named "Beijing Miyun District Medical Consortium Construction & General Practitioners' Comprehensive Capability Improvement Project" to attend a semi-structured group interview for understanding the status of clinical encounters of GPs with pediatric patients and related influencing factors. The interview results were recorded, and transcribed, then coded using NVivo 12, and analyzed using thematic analysis. Results Nineteen GPs (5 men and 14 women) in the age range of 24-51 years〔average age of (33.2±7.6) years〕, attended the interview, 18 of whom had a bachelor degree; 9 had a title of attending physician; 1 had participated in the standardized general practice residency program; 8 had participated in the "3+2" assistant general practitioners training program; 8 had participated in the standardized training before making a career change into general practice. The average years of them working a GP was 1-18 years〔 (6.3±4.8) years on average〕. Four themes emerged from the analysis: (1) Both the numbers of pediatric patients and illnesses encountered by suburban GPs were less than those encountered by their urban counterparts, and pediatric patients encountered by suburban GPs aged greater than or equal to 3 years. (2) Suburban GPs generally had a low level of self-confidence in treating pediatric patients. (3) The major factors negatively affected suburban GPs encountering pediatric patients include the pediatric patient's parents with a lower level of trust in their GP, inadequate capabilities of GPs in managing pediatric patients, high risk of managing pediatric patients, underperformance of nurses, inadequate available pediatric medicines and equipments for laboratory tests in the community, and lack of a clear referral system. (4) The major facilitators for suburban GPs to encounter pediatric patients include managing pediatric patients in the community by pediatricians, and increasing pediatric medicines and equipments for laboratory tests. Conclusion The encounters of suburban GPs with pediatric patients in primary care were unsatisfactory due to many problems and challenges. To improve the situation, it is suggested to improve the capabilities of suburban GPs in managing pediatric patients by trainings, the collaboration between GPs and pediatricians, and the tiered system for the diagnosis and treatment of pediatric diseases.

The integration of atom clusters and single atoms into a unified system represents a desirable approach for attaining enhanced catalytic performance. Nonetheless, the controllable synthesis of a single‐atom and nanocluster integrated system (SA‐NC) faces considerable challenges, and the mechanisms underlying the catalytic activity remain poorly understood. In this research, a cobalt‐based catalyst containing both coordinatively unsaturated single‐atom (CoN3) and small nanoclusters (Co@SA‐NC) is synthesized. The Co@SA‐NC not only facilitates charge and mass transfer due to the interconnected long‐range micromorphology, thus endowing efficient oxygen electrocatalytic reaction (ORR/OER), but also undergoes surface reconfiguration upon OH adsorption at high potentials in alkaline ORR/OER conditions. More appealingly, this OH‐involved reconfigured adaptive structure promotes optimization of energy barriers owing to the dynamic regulation from the bridged OH between Co single‐atom and cluster in the whole reaction process. Specific to the application metrics, a zinc–air battery assembled using the Co@SA‐NC catalyst exhibit targeted power density enhancement with 270 mW cm−2 in an alkaline medium. This work offers an effective insight into the study of SA‐NC catalytic reaction pathways for efficient ORR/OER catalysis. [ABSTRACT FROM AUTHOR]

This paper proposes an effective material delivery algorithm to address the challenges associated with Unmanned Aerial Vehicle (UAV) material transportation and delivery, which include complex route planning, low detection precision, and hardware limitations. This novel approach integrates the Whale-Swarm Hybrid Algorithm (WSHA) with the APCR-YOLOv8 model to enhance efficiency and accuracy. For path planning, the placement paths are transformed into a Generalized Traveling Salesman Problem (GTSP) to be able to compute solutions. The Whale Optimization Algorithm (WOA) is improved for balanced global and local searches, combined with an Artificial Bee Colony (ABC) Algorithm and adaptive weight adjustment to quicken convergence and reduce path costs. For precise placement, the YOLOv8 model is first enhanced by adding the SimAM attention mechanism to the C2f module in the detection head, focusing on target features. Secondly, GhoHGNetv2 using GhostConv is the backbone of YOLOv8 to ensure accuracy while reducing model Params and FLOPs. Finally, a Lightweight Shared Convolutional Detection Head (LSCDHead) further reduces Params and FLOPs through shared convolution. Experimental results show that WSHA reduces path costs by 9.69% and narrows the gap between the best and worst paths by about 34.39%, compared to the Improved Whale Optimization Algorithm (IWOA). APCR-YOLOv8 reduces Params and FLOPs by 44.33% and 34.57%, respectively, with mAP@0.5 increasing from 88.5 to 92.4 and FPS reaching 151.3. This approach can satisfy the requirements for real-time responsiveness while effectively preventing missed, false, and duplicate detections during the inspection of emergency airdrop stations. In conclusion, combining bionic optimization algorithms and image processing significantly enhances the efficiency and precision of material placement in emergency management. [ABSTRACT FROM AUTHOR]

A multi-component blend of highly volatile ethanol with low volatile hydrogenated biodiesel and diesel is the subject of study. The internal vapor bubble dynamics and evaporation characteristics of individual droplets at high temperatures were investigated. The evaporation characteristics of droplet normalized square diameter and droplet lifetime of the blends of hydrogenated biodiesel, ethanol, and diesel were captured by means of the hanging droplet method and high-speed microscopic imaging in a constant temperature heating furnace. It is revealed that the rise in ambient temperature contributes to increasing the evaporation rate of fuel droplets and intensifies the micro explosion during evaporation and shortens the evaporation of droplets to a certain extent; Compared to diesel, the inhibition effect of evaporation is stronger with the increase of hydrogenated biodiesel in binary fuels and compared with binary fuels, ethanol in ternary fuels promotes micro explosions and shortens droplet evaporation; The droplet evaporation of binary fuels shows three typical phases of ethanol domination, ethanol, and diesel co-domination and co-evaporation of all three in sequence. [ABSTRACT FROM AUTHOR]