The Effects of Information-Seeking Behaviors on Risk Perception During the COVID-19 Pandemic: A Cross-Sectional Correlational Survey.

Background: The COVID-19 pandemic caused by the novel SARS-CoV-2 virus represents an ongoing public health challenge that necessitates a heightened need to understand people's risk perceptions as well as their information-seeking behavior. Objective: The aim of this study is to explore the impact of different information-seeking behaviors on people's risk perceptions during the COVID-19 pandemic. Methods: We employed convenience sampling in order to administer questionnaires to 3048 residents in Hunan Province, China. After screening the questionnaires for inclusion in the study, multiple linear regressions were then used to analyze the impact of the characteristics of respondents' information-seeking behavior on their risk perceptions. Results: From the 3048 distributed 2611 were included. New media (80.20%) was the most frequently used source of information seeking, and traditional media were participants' most trusted source of COVID-19 information. Statistics of COVID-19 were the type of information most frequently queried by respondents, and approximately 30.0% of them reported that most or all of the COVID-19 information they sought was negative. Approximately one in five respondents reported that they sought COVID-19 information more than 10 times per day. The results of our multivariate linear regression analysis showed that "seeking information from new media ", "level of trust in new media and local propaganda", "information content being about protective behaviors and personal related information", "proportion of negative information", and "frequency of information seeking" were positively associated, and "seeking information from traditional media" and "level of trust in traditional media" were negatively associated with people's risk perception of COVID-19. Conclusion: We find that specific types of channels of information acquisition and public trust in these information channels, their informational content, and proportion of negative information, as well as a frequency of information seeking all had an impact on risk perception during COVID-19.

Construction of a theoretical model for fan nozzles with precise atomization angles for plant protection.

The fan nozzle is widely used in the process of pest control in agriculture and forestry. The spray angle of the nozzle is an important characterization parameter in the atomization of liquids. The spray angle of the nozzle is an important characterizing parameter in the liquid atomization process. It affects the flow field at the exit of the nozzle, thereby affecting the size and velocity of the droplets, and further affecting the deposition effect of the droplets on the crop. Therefore, its research is of great significance for improving the deposition of liquid on plants and controlling pests and related diseases. Based on the classical theory of predecessors and considering the parameters of the flat fan nozzle, we further optimized the theory at the structural level by means of a simulation test and built a spray angle theoretical model taking into account the parameters of the inner chamber of the nozzle. We arrived at the following conclusions: (1) the average error of the spray angle measured by the simulation test and the actual test spray angle was 2.95%, the maximum spray angle deviation value was 2.81°, and the result proves that the simulation test parameter setting is accurate; and (2) the average error between the actual measured value and the theoretical model calculation value was 3.56%, the maximum spray angle deviation was 4°, through the actual test comparison, and the spray angle error of the theoretical model was within the allowable error range of industry production. It was proved that the model could effectively reflect the changing law of spray angle of the flat fan nozzle.

Analysis of droplet size uniformity and selection of spray parameters based on the biological optimum particle size theory.

Based on the theory of biological optimal particle size, the most easily attached droplets for different organisms have different particle sizes. To achieve the best average particle size, the droplet size in the atomization field must be more uniform and attain a high the adhesion rate. Therefore, during the application process, not only the average particle size of the droplets but also the influence of the uniformity of the droplets in the spray field must be considered. In this study, 20 small-angle fan nozzles ranging from 20° to 40° are used as the research objects. The droplet size information in the atomization field is obtained using a laser particle size analyzer, and the droplet uniformity under different parameters is calculated. The results showed that within the range of the parameters selected in the experiment, the droplet size increased with an increase in the flow rate, and decreased with an increase in the pressure. In addition, the angle had little effect on the droplet size. Increasing the spray height, spray angle, and pressure, while reducing the equivalent outlet diameter of the nozzle was beneficial to improve the uniformity of droplets. The order of the degree of influence of the four parameters on the uniformity of the droplets was height > equivalent outlet diameter (r) > pressure > spray angle, and the influence weights were 51.1%, 37.1%, 7.8%, 4.1%; 48.4%, 37.6%, 10%, and 4%. Under the condition of the parameter settings used in this experiment, the optimal atomization effect for the four intervals of 150-200 µm, 200-250 µm, 250-300 µm, and 300-400 µm was analyzed from the perspective of uniformity. The nozzle models with the best atomization effects in each interval were SS4003-0.3 MPa, SS4006-0.3 MPa, SS4008-0.3 MPa, and 633.512.30.CC-0.1 MPa.

Development and psychometric assessment of the public health emergency risk perception scale: Under the outbreak of COVID-19.

OBJECTIVE: Correctly understanding and evaluating the level of public risk perception toward public health emergencies not only helps experts and decision-makers understand the public's preventative health behaviors to these emergencies but also enhances their risk information communication with the public. The aim of this study was to develop a risk perception scale for public health emergencies and test its validity and reliability during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: Guided by the theoretical model of risk perception, an initial scale was generated through literature review, group meetings, resident interviews, and expert consultation. A pretest and item screening were then conducted to develop a formal risk perception scale for public health emergencies. Finally, the reliability and validity of the scale were validated through a questionnaire survey of 504 Chinese adults. RESULTS: The final scale had 9 items. The content validity index of the scale was 0.968, and the content validity index of individual items ranged from 0.83 to 1.00. Three common factors, dread risk perception, severe risk perception, and unknown risk perception, were extracted for exploratory factor analysis, and together they explained 66.26% of the variance in the score. Confirmatory factor analysis showed that the model had a satisfactory fit, where χ 2/df = 1.384, the goodness-of-fit index (GFI) = 0.989, root mean square error of approximation (RMSEA) = 0.028, root mean square residual (RMR) = 0.018, comparative fit index (CFI) = 0.995, normed fit index (NFI) = 0.982, and non-normed fit index (NNFI) = 0.990. The correlations between dimensions ranged from 0.306 to 0.483 (P < 0.01). Cronbach's α was 0.793 for the total scale and ranged between 0.687 and 0.801 for the individual dimensions. The split-half coefficient was 0.861 for the total scale and ranged from 0.727 to 0.856 for induvial dimensions. The test-retest coefficient was 0.846 for the total scale and ranged from 0.843 to 0.868 for induvial dimensions. CONCLUSION: The developed scale for the risk perception of public health emergencies showed acceptable levels of reliability and validity, suggesting that it is suitable for evaluating residents' risk perception of public health emergencies.