Climate change has a significant impact on the growth and distribution of vegetation worldwide. Hydrangea macrophylla is widely distributed and considered a model species for studying the distribution and responses of shrub plants under climate change. These results can inform decision‐making regarding shrub plant protection, management, and introduction of germplasm resources, and are of great importance for formulating ecological countermeasures to climate change in the future. We used the maximum entropy model to predict the change, scope expansion/reduction, centroid movement, and dominant climate factors that restrict the growth and distribution of H. macrophylla in China under current and future climate change scenarios. It was found that both precipitation and temperature affect the distribution of suitable habitat for H. macrophylla. Akaike information criterion (AICc) was used to select the feature combination (FC) and the regularization multiplier (RM). After the establishment of the optimal model (FC = QP, RM = 0.5), the complexity and over‐fitting degree of the model were low (delta AICc = 0, omission rate = 0.026, difference between training and testing area under the curve values = 0.0009), indicating that it had high accuracy in predicting the potential geographical distribution of H. macrophylla (area under the curve = 0.979). Overall, from the current period to future, the potential suitable habitat of this species in China expanded to the north. The greenhouse effect caused by an increase in CO2 emissions would not only increase the area of high‐suitability habitat in Central China, but also expand the area of total suitable habitat in the north. Under the maximum greenhouse gas emission scenario (RCP8.5), the migration distance of the centroid was the longest (e.g., By 2070s, the centroids of total and highly suitable areas have shifted 186.15 km and 89.84 km, respectively).

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In the last three years, the most commonly occurring topic in people’s day-to-day dialogue has inevitably been the corona-virus disease 2019 (COVID-19). At the same time, it is embodied in various aspects of our lives. For example, keeping social distance, wearing masks, getting vaccinated, staying at home order, working at home have had an impact on people's lives. With the tendency of COVID-19 mutations, more people are being diagnosed or even dying. In addition to this, there is a significant risk of sequelae in those who are recovered. However, there are still no other options such as medical treatment to stop the occurrence of COVID-19 completely. Therefore, this research examines the changes affecting the causes of COVID-19 deaths for these conditions. While many researchers have explored relevant topics during the period affected by the epidemic, this research provides a fairly comprehensive overview of age (11 age groups), sex (male and female), vaccination status, and alterations in the overall number of diagnoses and fatality cases since COVID-19's inception up until the present. It is possible to obtain from the detailed investigation whether there is a significant relationship between COVID-19 and age, sex, and vaccination status. This research includes Box plots and Anova test for different age groups and sexes, and line graphs of the number of vaccinations, the amount of COVID-19 mortality in the United States, and the amount of COVID-19 confirmed cases and mortality worldwide to compare, interpret, and analyze the data to obtain conclusions.

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In order to improve the cotton bast utilization,the chemical degumming technology was adopted to process cotton bast to remove the hemicellulose, lignin , pectin and other substances in this topic.The method of nitric acid or sodium hydroxide was used to extract the cellulose,which was dissolved into a film in the copper ammonia solution. Finally,the proper film-forming process was selected by testing the physical properties of membrane.