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Because the elastic scattering cross sections of medium-mass nuclides have very strong elastic scattering resonance phenomenon in the fast neutron region, which will lead to the self-shielding effect of energy scale and make distortions of the neutron flux distribution to zigzagging. In order to accurately describe the distribution of neutron flux in the energy scale, the deterministic one-step method needs to divide a large number of energy intervals for description, and the number of energy groups is generally thousands. Deterministic one-step transport calculation has large memory and low computational efficiency with thousands of groups. In the traditional calculation of the whole-core non-uniform transport calculation for the thousands of groups, the section generation software was mainly used to prepare the self-shielding cross section by using the ultra-fine groups, and then the broad-group cross section was prepared offline by the transport calculation of the equivalent model of cells or components. Finally, the deterministic one-step program was used to calculate the whole-core non-uniform transport. The broad-group cross sections prepared off-line cannot reflect the characteristics of materials of different reactor locations and bring the approximations. In order to solve the problem that the thousand-group energy structure of fast reactors leads to the high computational cost of the deterministic one-step method, an online energy group condensation method with fine group energy spectrum based on SHARK was developed. For the fuel cells of fast reactors, it can keep the composition of fuel and other materials unchanged and search the radius of the fuel to make the escape cross section conserved. It has the capability of online equivalent model establishment, online calculation of fine group energy spectrum and broad group cross sections condensation. For non-fuel cells, the broad group cross section was condensed using the fine group energy spectrum calculated by the one-dimensionalal constant volume model of practical problems. Based on the MOX1000 material of the benchmark for neutronic analysis of sodium-cooled fast reactor cores, a two-dimensional 5×5 rectangular single-assembly problem and a two-dimensional 3×3 multi-assembly problem were constructed and calculated. The numerical results show that compared with the calculation results of the group in 1 968, the acceleration ratio of the online energy group condensation method in the two-dimensional 5×5 rectangular single-assembly problem is 8 to 18 and that in the two-dimensional 3×3 multi-assembly problem is 12 to 17, which can significantly improve the calculation efficiency. In terms of calculation accuracy, the relative deviation of pin power distribution is less than 1%, and the maximum deviation of eigenvalue is about 360 pcm. It is of great significance to deterministic one-step method for fast reactor transport calculation.

Compared with the variables separation method and integral-transform method, Green’s function method is much more applicable and thus of great practical significance. Based on the general steps of Green’s function method, a new method is originally raised to get Green’s function in oil and gas flow problems through underground formations. After that, the transient pressure solution is get for flow in a spherical reservoir by using this method. This case enlarged the application of Greenʼs method function, and this work can also be a good foundation for the solution of more and more complicated flow problems in oil and gas reservoirs.

Malignant tumors can be classified into three categories， rapidly progressing tumors， slowly progressing tumors， and "indolent" tumors. Rapidly progressing tumors （such as liver cancer， pancreatic cancer， and cholangiocarcinoma） have acute onset， shorter time duration from onset to death， and poorer treatment effects， which warrants primary prevention. Slowly progressing tumors （such as lung cancer， colorectal cancer， breast cancer， and gastric cancer） have slow onset， clear precancerous lesions， longer time duration from onset to death， and better therapeutic effects， which is accordingly suitable for secondary prevention. “Indolent” tumors （such as prostate and thyroid cancer） do not affect the life expectancy and are suitable for tertiary prevention. Early screening of “indolent” tumors may lead to overtreatment. Furthermore， early screening of rapidly progressing tumors is difficult to identify early cancers， which results in low cost-effectiveness. In contrast， for slowly progressing tumors suitable for secondary prevention， early screening may have cost-effectiveness， though there might be over-diagnosis. It is crucial to adopt appropriate prevention and treatment strategies for diverse types of tumors. Currently， large-scale cohort studies and randomized controlled clinical trials with complete follow-up may accurately evaluate the effect of cancer prevention strategies. This review discusses the significance of screening in precision prevention of tumors based on the characteristics of tumor progression and patients’ prognosis.

The relevance of the study is due to the interest of Russian and Chinese science in artistic capture of the processes taking place on the territory of the Far Eastern frontier – Manchuria and the Far East in the first half of the 20th century. In a situation of political chaos, economic confusion and civil wars in these lands, the phenome non of hunkhuznichestvo arises, which has become a real disaster for civilians. This problem is covered in great detail in the literature of the Far Eastern emigration and historical, literary works. The novelty of the research is determined by the appeal to Chinese sources (scientific and literary), which until now have not been systematically studied from the point of view of the ethnocultural, ethnosocial and literary paradigm. The problem lies in the comparative analysis of historical, socio-political materials (dictionaries, chronicles, scientific articles) and the results of the artistic reception of the phenomenon of hunkhuznichestvo in the works of northeastern writers of the 1920s–1940s. The aim of the work is to study the images of the Hunghuz from the point of view of the socio-political, ethno-cultural request of the emerging Chinese national consciousness of the 1920s–1940s and their artistic interpretation by Xiao Jun. The main methods are historical-genetic (reconstruction of the formation of ideas about Hunghuz in the Chinese mind), cultural-historical (study of images of Hunghuz in the context of the formation of the literature of the “Left Wing” and the influence of Soviet models), comparative-historical (comparison of images of Hunghuz in literature of the 1920–1940 and their subsequent reception in the Chinese public consciousness), biographical (the influence of the family’s upbringing and the author’s inner circle on his perception of hunkhuzism), translation methods (translation of Chinese scientific works, dictionary entries, historical documents, Xiao Jun’s novels) and the method of immanent analysis (in relation to the above-mentioned texts by the author studied). When writing his novels (Village in August, Third Generation) Xiao Jun drew not only on the ideologemes of the communist movement in China, literary examples of Soviet heroic-romantic prose about the civil war, but also on his personal experience of knowledge of hunkhuzism. The author comes to the conclusion that Xiao Jun recorded important historical and cultural ethnocultural, ethnopsychological, ethnoreligious details of Hunghuz life, customs, original ethos.

Medical research is important to scientific progress and medical education. Institutions worldwide have sought to increase student involvement in research such as clinician-scientists training programs, while little is known about how medical undergraduates perceive research. A cross-sectional study was conducted in Chongqing Medical University, Chongqing, China, with first--fourth year undergraduates. An online, anonymous, and self-rating 5-point Likert questionnaire was conducted to investigate medical undergraduates' demographic characteristics and assess motivation, self-efficacy, perception, curiosity, and barriers regarding medical research. Content validity was checked with experts and face validity was checked for clarity and understanding of the questionnaire. The Cronbach's alpha coefficient of the questions ranged from 0.813 to 0.879. A total of 3273 medical undergraduates were surveyed, and 86.62% (2835) participants (male 962, female 1873) were identified as effective. Males scored higher than females on self-efficacy (p < 0.001), perception (p = 0.017), and curiosity (p < 0.001), and lower on barriers (p < 0.001). The second year students are at the peak of their perception (p = 0.006) and lowest barrier scores (p = 0.003). Students with scientific research experience scored higher in motivation (p = 0.002), self-efficacy (p < 0.001), perception (p < 0.001), and curiosity (p < 0.001). Lack of proper mentoring opportunity (86.2%) and knowledge (84.5%) were the main barriers in conducting research. Even though they have a positive perspective, only a few undergraduates enrolled in research. Medical universities should encourage faculties to supervise and guide undergraduates' projects, and provide feasible solutions for students to learn scientific knowledge and skills. It is vital to build a research-oriented environment and academic atmosphere.