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Extrusion molding die heads play a critical role in film production, with their structure directly influencing product quality, production efficiency, and die life cycle. This study focused on optimizing the film blowing process by designing a new spiral die head and analyzing the flow field dynamics. The model was constructed via a three-dimensional Boolean operation following fluid mechanics principles to establish a mathematical model based on the die head's structure and material properties. By varying parameters such as the inlet flow rate, buffer groove length, shaping section length, and non-Newtonian index, the velocity and pressure fields were analyzed using the finite element method. The results show that increasing the inlet velocity and non-Newtonian index significantly impacted the velocity uniformity, inlet and outlet pressure, and pressure drop. A higher inlet velocity led to increased fluctuations in outlet velocity and a higher inlet pressure, while a higher non-Newtonian index resulted in a more uniform outlet velocity and a reduced fluctuation, though with a higher inlet pressure and flow channel pressure drop. The lengthening of the buffer groove and shaping section had minimal effect on the outlet velocity uniformity but increased the inlet and outlet pressures and pressure drop at each stage. This study concluded that a uniform velocity distribution, lower pressure, and reduced energy consumption are crucial for high-quality film production. The optimal parameter values were found to be an inlet flow rate of 0.03 m/s, buffer groove length of 40 mm, shaping section length of 20 mm, and non-Newtonian index of 0.36. These findings provide a theoretical foundation for optimizing die head design and improving thin film quality in practical applications. [ABSTRACT FROM AUTHOR]

The development of a city needs the accumulation of culture, and historical buildings are the most direct witness of the rise and fall of a city. Like the human body, historical buildings have a certain life cycle, but the acceleration of urbanization and unreasonable use cause an irreversible reduction in the residual life of historical buildings. There is a notable lack of quantitative analysis regarding the residual life of historical buildings. Therefore, identifying the factors that influence their residual life is crucial for both preserving these buildings and sustaining urban culture. In order to obtain a more accurate correlation degree of influencing factors, a systematic-analysis model of influencing factors on the residual life of historical buildings based on the entropy weight method (EWM) and the grey relation analysis method (GRA) was established, so as to excavate the mechanism of the influencing factors on the residual life of historical buildings, accurately identify the main influencing factors on the residual life of historical buildings, and propose preventive measures. The results show that the structural system has the greatest influence on the residual life of historical buildings, followed by the enclosure system, and the equipment system. The research findings offer valuable insights for extending the residual life of historical buildings in the future. [ABSTRACT FROM AUTHOR]

Urbanization transforms landscapes from natural ecosystems to configurations of impervious surfaces and green spaces, leading to urban heat island effects that impact health and ecosystem sustainability. This study in Xiamen City, China, categorizes urban areas into functional zones, employs Random Forest and Stepwise Regression models to assess thermal differences, and proposes optimization measures for the building–green space landscape. The optimization involves altering the characterization of the building–green space landscape pattern. Results indicate: (1) due to the spatial heterogeneity of the building–green space landscape pattern in different functional zones, the surface temperature also shows strong spatial heterogeneity in different functional zones; (2) different optimization measures for the building–green space pattern are needed for different functional zones; taking the urban residential zone as an example, the Normalized Difference Vegetation Index (NDVI) in the hot spot area can be adjusted according to the value range of the cold spot area; (3) considering the solar radiation process, Sun View Factor (SunVF) plays an important role in indicating the change in surface temperature in the commercial service area, and as SunVF increases, the surface temperature of the functional zone tends to rise. This research offers insights into urban thermal environment improvement and landscape pattern optimization. [ABSTRACT FROM AUTHOR]

Although understandings of scientific inquiry (as opposed to conducting inquiry) are included in science education reform documents around the world, little is known about what students have learned about inquiry during their elementary school years. This is partially due to the lack of any assessment instrument to measure understandings about scientific inquiry. However, a valid and reliable assessment has recently been developed and published, Views About Scientific Inquiry (VASI; Lederman et al. [2014], Journal of Research in Science Teaching, 51, 65-83). The purpose of this large-scale international project was to collect the first baseline data on what beginning middle school students have learned about scientific inquiry during their elementary school years. Eighteen countries/regions spanning six continents including 2,634 students participated in the study. The participating countries/regions were: Australia, Brazil, Chile, Egypt, England, Finland, France, Germany, Israel, Mainland China, New Zealand, Nigeria, South Africa, Spain, Sweden, Taiwan, Turkey, and the United States. In many countries, science is not formally taught until middle school, which is the rationale for choosing seventh grade students for this investigation. This baseline data will simultaneously provide information on what, if anything, students learn about inquiry in elementary school, as well as their beginning knowledge as they enter secondary school. It is important to note that collecting data from all of the approximately 200 countries globally was not humanly possible, and it was also not possible to collect data from every region of each country. The results overwhelmingly show that students around the world at the beginning of grade seven have very little understandings about scientific inquiry. Some countries do show reasonable understandings in certain aspects but the overall picture of understandings of scientific inquiry is not what is hoped for after completing 6 years of elementary education in any country.

Wuyi rock teas of different storage duration have different flavor, bioactivity, and market value, Shuixian is a main variety of Wuyi rock tea. In this study, metabolites composition of Shuixian with different storage years were analyzed using Ultrahigh Performance Liquid Chromatography‐Quadrupole‐Time of Flight‐Mass Spectrometry (UPLC‐Q‐TOF‐MS). A total of 1201 compounds were identified, and 104 differential compounds (VIP > 1.5) were determined. Furthermore, the results showed that five compounds exhibited a positive correlation with storage time, such as alpha‐terpineol formate, carnosol, 2‐phenethyl‐D‐glucopyranoside, Ellagic acid, and D‐ribosyl nicotinic acid, while 24 compounds showed a negative correlation, such as Ethyl linoleate, leucocyanidin, cis‐3‐hexenyl acetate. In total, 29 signature compounds significantly correlated with storage time. These findings shed light on the patterns and mechanisms of changes in the composition of Wuyi rock tea during storage and provide a theoretical foundation for distinguishing the storage years. [ABSTRACT FROM AUTHOR]

To construct a real-time data resource set for pediatric clinical cases. Methods: This study was conducted within the framework of a university-level medical data center where advanced data de-identification protocols and encryption technologies were employed. The inclusion criteria for cases were determined based on their distinctive clinical characteristics and educational relevance aligning with established curriculum standards. These cases were then incorporated into the case library. To ensure ongoing enrichment and relevance of the pediatric clinical teaching case library, a two-phase evaluation system focused on aspects of storage-use and quality-availability was implemented. Results: This study successfully established a pediatric clinical teaching case library, supported by substantial real-time data. This database has been seamlessly incorporated into various facets of pediatric education, including classroom instruction in Pediatrics, serving as a resource for educational material and facilitating in practical teaching scenarios. Conclusion: This case library provides an authentic and dynamic data foundation for clinical teaching by leveraging a vast repository of real-time clinical data. It not only facilitates access to high-quality educational resources but also promotes the exploration and adoption of interdisciplinary teaching methodologies. Future research should clarify the theoretical foundation for the application of real-time data, fill existing theoretical gaps, and explore its applicability in various educational environments. [ABSTRACT FROM AUTHOR]