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Currently, tapping is the only method of obtaining natural rubber, an essential industrial raw material. The stability of the labor force supply for tapping is crucial for the sustainable development of the natural rubber industry. As China's second-largest rubber planting area, Hainan Island had a planting area of 585,800 hectares in 2020, accounting for 45% of the country's total, with over 2 million workers. Labor force shortages and the aging phenomenon in tapping have become increasingly severe and have attracted significant attention. However, the related research lacks detailed spatial information for conversion estimation, which hinders macroeconomic regulation. This study is based on the 2020 Hainan Island natural rubber distribution map, Dynamic World land use classification products, and the WorldPop population distribution dataset. It employs multiple technical operations such as temporal and spatial filtering, removal of small patches, buffer parameter settings, and masking to obtain the 2020 potential tapping labor density map for Hainan's rubber planting areas. Spatial statistical methods are used to analyze the spatial distribution and age structure characteristics of potential tapping labor force in Hainan's rubber planting areas as well as the spatial distribution of labor force shortage degrees after conversion to actual tapping labor force, including the labor force shortage levels and areas for each city and county, revealing the spatial pattern. The results reveal the following: 1) The total number of potential tapping laborers in Hainan's rubber planting areas is 1.567 4 million, with a spatial distribution pattern of high in the north and low in the south. The proportion of the population aged 45~59 years is 34%, indicating a significant aging trend. 2) There are significant spatial differences in the degree of labor shortage. The primary shortage areas are mainly concentrated in the junction areas of the central-western and central-eastern counties, with a belt-like distribution. In contrast, the secondary and tertiary shortage areas are widely distributed in the central-western, central, and some central-eastern county junctions, with shortage in the central area being particularly severe, showing a contiguous distribution. 3) The primary shortage areas in Danzhou City, Baisha County, and Qiongzhong County rank in the top three, with a cumulative area of 50,500 hectares. Baisha, Qiongzhong, Chengmai, and Ledong Counties are also prominent in the secondary and tertiary shortage areas, covering a total area of 23,300 hectares. In total, the area of labor shortage regions in Hainan Island is 141,700 hectares, necessitating a future focus. To address the labor force shortage issue in tapping, it is recommended to strengthen infrastructure construction in the rubber plantations within the shortage areas and actively promote new tapping methods (e.g., low-frequency tapping) or tools (e.g., electric tapping knives) to reduce the labor intensity of tapping and increase the number of trees tapped per capita. This will provide favorable support for the sustainable and healthy development of Hainan's natural rubber industry. By revealing the spatial distribution characteristics and degree of tapping labor shortage, this study aims to provide robust decision-making support for the Hainan provincial government in addressing employment issues of tapping labor, optimizing human resource management strategies, and promoting the sustainable development of the natural rubber industry.

Orthodontic resident training has a long history abroad. Its purpose is to teach general practitioners in dentistry about basic knowledge and operating standards and to lay a solid foundation for the normalization and standardization of techniques. Osaka Dental University, established in 1911, is one of the oldest dental higher education facilities in Japan and Asia. Its systematic orthodontic resident training program has specific characteristics, including a thorough foundation in basic training, sufficient practice time in clinical work, and an emphasis on both clinical thinking ability and technical detail mastery. Recently, orthodontic resident training programs in China have achieved significant progress in a short period. In this manuscript, we introduce the orthodontic training program of Osaka Dental University in terms of enrollment, training arrangements, orthodontic basic education and clinical training in order to offer a reference for the continuous improvement of the standardized training system for resident doctors of stomatology in China.

Objective: To investigate the expression of forkhead box protein D3 (FOXD3) in gastric cardia adenocarcinoma (GCA) and its effect on the biological behaviors of SGC-7901 cells. Methods: A total of 49 pairs of GCA tissues and corresponding paracancerous tissues that surgically resected from June 2014 to December 2016 were selected from the Biological Specimen Library of the Fourth Hospital of Hebei Medical University. qRT-PCR was used to detect the expression of FOXD3 in GCA tissues and corresponding para-cancerous tissues, as well as in gastric cancer cell lines(BGC-823, SGC-7901, HGC-27, MGC-803, and NCI-N87). pc-DNA3.1-FOXD3 or pc-DNA3.1 was transfected into SGC-7901 cells. Cell proliferation assay, clone formation assay, scratch healing assay, and Transwell chamber invasion assay were used to detected the effect of FOXD3 overexpression on the the proliferation, clone formation, migration, and invasion of SGC-7901 cells. The mRNA and protein expressions of epithelial-mesenchymal transition (EMT) related molecules before and after the transfection were detected by qRT-PCR and WB. Cell cycle changes before and after transfection were detected by Flow cytometry. Results: The expression of FOXD3 mRNA in GCA tissues was significantly downregulated, and it's expression was closely correlated with clinical stage and lymph node metastasis of GCA patients. The expression of FOXD3 in gastric cancer cell lines was lower than that in normal cell lines (all P<0.01). FOXD3 overexpression significantly inhibited the proliferation, clone formation, migration and invasion of SGC-7901 cells in vitro (all P<0.01). FOXD3 overexpression could up-regulate the expression of E-cadherin and down-regulate the expressions of N-cadherin, β-catenin and vimentin in SGC-7901 cells (all P<0.01). Overexpression of FOXD3 could arrest the cell cycle in the G0/G1 phase (P<0.01). Conclusion: The expression of FOXD3 in GCA tissues is significantly downregulated, and its overexpression can inhibit the biological behaviors of gastric cancer cells. FOXD3 can be used as a tumor suppressor gene to provide new ideas for tumor therapy. [ABSTRACT FROM AUTHOR]