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The stop signal is produced in response to negative experiences at the food source and inhibits honey bee (Apis mellifera) waggle dancing. Here, we present a protocol for measuring the effects of an inhibitory signal associated with danger on honey bee dopamine levels. We describe steps for observing honey bee colonies, training them with artificial nectar, and simulating hornet attacks. We then detail procedures for recording waggle dancing and stop signals and measuring brain dopamine levels during different treatments. For complete details on the use and execution of this protocol, please refer to Dong et al.1.

Positive and negative experiences can alter animal brain dopamine levels.1 When first arriving at a rewarding food source or beginning to waggle dance and recruit nestmates to food, honeybees have increased brain dopamine levels, indicating a desire for food.2 We provide the first evidence that an inhibitory signal, the stop signal, which counters waggle dancing and is triggered by negative events at the food source, can decrease head dopamine levels and dancing, independent of the dancer having any negative experiences. The hedonic value of food can therefore be depressed simply by the receipt of an inhibitory signal. Increasing the brain dopamine levels reduced the aversive effects of an attack, increasing the time that bees spent subsequently feeding and waggle dancing and decreasing their stop signaling and time spent in the hive. Because honeybees regulate food recruitment and its inhibition at the colony level, these results highlight the complex integration of colony information with a basic and highly conserved neural mechanism in mammals and insects.2 VIDEO ABSTRACT.

[Objective] To explore the effectiveness of the Revised Universal Soil Loss Equation (RUSLE) model in simulating soil erosion on slope surfaces during vegetation restoration in the Loess Plateau. [Methods] This study utilized rainfall-runoff and sediment data from ten runoff plots in Ansai Fangta small watershed in northern Shaanxi Province during 2016—2022. Utilizing various commonly used algorithms for RUSLE model factors specific to the Loess Plateau, a total of 144 combinations of factors were simulated to estimate soil erosion on restored slopes. The Nash-Sutcliffe efficiency coefficient (NSE) and root mean square error (RMSE) were used to evaluate the effectiveness of the model simulations. [Results] The results indicated that the simulated soil erosion on restored slopes using the 144 factor combinations ranged from -38.47 to 0.19 for NSE and from 1.92 to 12.65 t/(hm2·a) for RMSE, suggesting limited model performance. The selected algorithms for RUSLE model factors appeared to be inadequate for assessing soil erosion on slopes undergoing vegetation restoration. Further improvements are needed for the individual factors within the RUSLE model. When applying RUSLE model to simulate soil erosion on restored slopes in the Loess Plateau, it is recommended to utilize data with high temporal resolution to reduce errors in calculating the R-factor, and comprehensively consider the effects of soil physical and chemical properties such as soil organic matter content, soil particle size and aggregate structure and bulk density on K-factor, and the the effects of vegetation coverage, vegetation height, litter, and biological crust and C-factor, full consider to slopes steeper than 10° in refining the LS-factor. [Conclusion] The RUSLE model is not well-suited for simulating soil erosion in the context of vegetation restoration on abandoned slopes in the Loess Plateau.This study provides some reference for the research and development of soil erosion model and the application of RUSLE model on the slope of vegetation restoration in the Loess Plateau.

Built environments have complex effects on the public's physical and mental health. Revealing the mechanisms and pathways through which the urban built environment influences public health can provide a basis for optimizing built environments. This helps avoid issues, such as environmental pollution, lack of social interaction, and insufficient physical activity, ultimately contributing to the enhancement of public health. Western academia has a more established foundation for research, whereas domestic endeavors are currently in the exploratory phase. A comparative analysis of relevant domestic and international studies can help elucidate the developmental trajectory of research in this field, identify common issues and characteristics, and guide the direction for advancing domestic research. Therefore, based on the Web of Science and China National Knowledge Infrastructure databases, this study systematically reviewed 658 English and Chinese studies published from 2000 to 2022 in the fields of urban and rural planning, geographic sciences, health medicine, and environmental psychology, focusing on the impact of the built environment on public health. Utilizing "Citespace" software, this study conducted a quantitative analysis and systematic review of the theoretical framework, study topics, and emerging trends in the research. The findings revealed disparities between Western and Chinese academies in terms of theoretical innovation, study groups, and research content. Specifically, international studies have pioneered theoretical perspectives, such as social welfare and environmental justice. Guided by these theories, researchers have explored the mechanisms through which the built environment affects public health in diverse population groups. Although domestic studies exhibit a relative lack of theoretical innovation, their primary focus has been the introduction and empirical application of Western theories in the Chinese context. These studies often concentrate on the transmission paths of the impacts on the older and women groups through static empirical evidence, lacking dynamism in their approaches. Furthermore, drawing upon the previously stated theoretical underpinnings, methodological approach, and research content, this paper summarized the analytical framework of "Built Environment Elements, Mediated Impacts, and Public Health." It meticulously examined the differential effects of three spatial elements—green space, land use, and road traffic—on public health. This study provides a detailed analysis of the mechanisms involved, highlighting the ecological and psychological benefits arising from exposure to and interactions with green spaces. It also analyzes how judiciously designed and compact land use patterns shape travel preferences, reduce travel distances, mitigate reliance on motor vehicles, and enhance the frequency of individual activities. Furthermore, the study outlines the ramifications for optimizing the road network system and transitioning travel modes to ameliorate traffic pollution, alleviate traffic pressure, and mitigate pedestrian injuries, among other variables. The purpose of this study was to systematically comprehend the current status and disparities in domestic and international research concerning the impact of the built environment on public health and to explore a series of health issues triggered by the built environment from the perspective of urban planning, with the hope of promoting health geography in China, offering guidance for future academic directions, and prompting local management authorities to formulate precision policies addressing public health challenges.