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【Objective】 Hetao irrigation district is one of the largest surface water-irrigation districts in north China. Keeping groundwater table below a critical depth is essential to preventing salt accumulation in the root zone, and the purpose of this paper is to study the suitable groundwater depth for healthy growth of different crops. 【Method】 The experimental area is at Jiefangzha within the irrigation district. Planting structure in the area was analyzed using decision tree classification method, and groundwater depth was estimated using the Kriging interpolation method, from which we calculated the mean NDVI. The suitable groundwater depth and salinity threshold for crops at different locations were obtained from the scatter diagram of groundwater salinity and its NDVI. 【Result】 ①The suitable groundwater depth for maize at its jointing, heading and filling stages was 1.2~1.7, 1.3~1.8 m and 1.3~1.8 m, respectively, while for winter wheat, the suitable groundwater depth at its jointing, heading and filling stages was 1.1~1.6, 1.1~1.6 m and 1.2~1.7 m, respectively. The suitable groundwater depth for sunflower at its bud and filling stages was 1.1~1.6 m and 1.2~1.7 m, respectively. ②The groundwater salinity critical for crop growth is 5 g/L, with groundwater salinity in the range of TDS≤3 g/L, 35 g/L being most suitable, suitable and not suitable for crop growth, respectively. 【Conclusion】 Controlling groundwater table at suitable depths with groundwater salinity not exceeding the critical concentration is essential to improving groundwater use efficiency and sustaining crop production in Hetao Irrigation district. For the area we studied, the suitable groundwater depth varies with crops and their growth stages, but the critical groundwater salinity is approximately the same for all crops.

This study proposes a second digital divide measurement for university students in Guangdong, encompassing internet usage proficiency and internet-enabled learning levels. Drawing on information literacy theory, the dimensions of information awareness, acquisition, storage, retrieval, utilization, and ethical/security considerations are individually assessed. A total of 1038 valid responses were collected through a questionnaire survey, and data analysis was conducted using descriptive statistics and variance analysis. The internet usage and enabled learning levels of university students in Guangdong are found to be moderately above average. The second-level digital divide among university students in Guangdong is complex, resulting from the interactive effects of personal factors, growth environment, and university environment. Personal characteristics (gender, grade), growth environment (average living expenses, parental education, family location, growth location, family learning environment), and campus learning environment have a significant impact on both the level of internet usage and internet-enabled learning. Conversely, personal characteristics (disciplinary category), and school location exhibit no significant impact on internet-enabled learning levels.

RNF180 is a type of ring finger protein with ubiquitin ligase activity, which can affect various physiological processes such as cell proliferation, differentiation and apoptosis by participating in the ubiquitinproteasome system. Studies have shown that RNF180 is mostly low-expressed in tumors, which can inhibit the proliferation and invasion of gastric cancer cells, and affect the lymph node metastasis and prognosis of gastric cancer. The gene expression silencing caused by the methylation of the promoter of RNF180 is the main reason for the low expression of RNF180 protein in tumors. Important methylation sites are related to precancerous lesions, lymph node metastasis of gastric cancer and patient prognosis. Therefore, RNF180 has the potential to become a biomarker of gastric cancer tumors.

Septin9 is a member of the cytoskeletal GTPase conserved family and is involved in a variety of biological processes. Many studies have shown that Septin9 is related to the occurrence and development of many malignant tumors. The methylated Septin9 gene can be used as a marker for early screening, diagnosis and prognosis of some malignant tumors, and may become a new target for anticancer therapy. This article reviewed the research progress of Septin9 gene and its methylation in common malignant tumors.

Aiming at the research of pure electric power transmission,the single low-power motor has the problems of low power,small speed range which can cause motor damage and the single high-power motor has the problem of large own load,large energy loss and other issues. A differential type parallel coupled input single output power transmission test bench is designed,the relationship between input and output speed and power loss when the load changed under different working modes is studied. The results of simulation test and the test bench test run shows,when the motor reaches steady state operation,the rated power is 0. 49 k W,the average output power is about 0. 482 k W,power loss is less than 10 W,speed range increases 29. 17%,transmission efficiency is greater than 81. 7%,output power is enhanced effectively and also has fine repeatability. The experimental research platform is provided for the further research on the dynamic optimization of the coupling transmission system.

BACKGROUND: While some evidence has potentially linked climate change to carcinogenic factors, the long-term effect of climate change on liver cancer risk largely remains unclear. OBJECTIVES: Our objective is to evaluate the long-term relationship between temperature increase and liver cancer incidence in Australia. METHODS: We mapped the spatial distribution of liver cancer incidence from 2001 to 2019 in Australia. A Bayesian spatial conditional autoregressive (CAR) model was used to estimate the relationships between the increase in temperature at different lags and liver cancer incidence in Australia, after controlling for chronic hepatitis B prevalence, chronic hepatitis C prevalence, and the Index of Relative Socio-economic Disadvantage. Spatial random effects obtained from the Bayesian CAR model were also mapped. RESULTS: The research showed that the distribution of liver cancer in Australia is spatially clustered, most areas in Northern Territory and Northern Queensland have higher incidence and relative risk. The increase in temperature at the lag of 30 years was found to correlate with the increase in liver cancer incidence in Australia, with a posterior mean of 30.57 [95% Bayesian credible interval (CrI): 0.17, 58.88] for the univariate model and 29.50 (95% CrI: 1.27, 58.95) after controlling for confounders, respectively. The results were not highly credible for other lags. DISCUSSION: Our Bayesian spatial analysis suggested a potential relationship between temperature increase and liver cancer. To our knowledge, this research marks the first attempt to assess the long-term effect of global warming on liver cancer. If the relationship is confirmed by other studies, these findings may inform the development of prevention and mitigation strategies based on climate change projections. https://doi.org/10.1289/EHP14574, Introduction Liver cancer is a disease with a heavy burden on patients. Global Burden of Disease Study 2019 (GBD 2019) reported that there were 534,000 new cases and 485,000 deaths [...]

Bionics is a subject which can interact with many disciplines including the drilling engineering. On the basis of analyzing the properties of bionic non-smooth surface, the non-smooth theory is applied in the bit design to develop the bionic diamond bit. The dung beetle is selected as bionic prototype in this paper to design the working layer of an impregnated diamond bit, which makes the bottom surface always keep the same non-smooth shape and makes the bionic bit maintain a high penetration rate and long-life to underline their high efficiency, wear and resistance reduction properties. Tests show that the bionic bit improves the drilling speed and lifetime by 44% and 74%, respectively, compared with a common bit. In addition, the bionic non-smooth surface structure has an extensive application prospect in drilling engineering, due to its properties of wear, anti-sticking and resistance reduction. It can be applied to improve the wear performance of bit, pipe joint, cylinder liner and piston of mud pump, and to solve the bit balling and reduce the resistance of spiral drills and impact spearhead. Key words: bionics, non-smooth theory, bionic diamond bit, application prospect