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The fracture problem of the functionally graded material with collinear cracks under the condition of different elasticity moduli. The stress fields and displacement fields of cracks in the functionally graded strip can be obtained by means of the method of integral transform. And solving the problem of cracks is equivalent to solving the problem of singular integral equations combined with boundary conditions and continuity conditions after solving the stress fields and displacement fields of each crack. The stress intensity factors can be obtained after solving the singular integral equations. The effects of elasticity moduli of materials and geometric parameters of cracks on SIFs are discussed. The results show that the distribution of elasticity moduli may affect SIFs significantly. And this study can provide scientific basis for forming FGMs and designing the property distribution in FGMs.

The newly increased cultivated land obtained through land consolidation has attracted great attention from the Chinese government and scholars since it concerns cultivated land protection and national food security. Hubei province is an important region for land consolidation in China amid serious cultivated land conversion and increasing demand of construction land due to rapid urbanization. In this paper, the spatial-temporal differences in 2001-2010 and the impact factors of this spatial difference in 2010 were analyzed to better understand the distribution of the newly increased cultivated land obtained through land consolidation in the province at the county level. All data used were acquired mainly from the land consolidation accounts and the statistical yearbooks. The research methods included the locational Gini-coefficient, geographic concentration and geographical detectors. Compared to other detective spatial analysis methods, the geographical detector was usable for both quantitative data and nominal data to extract the implicit interrelationships between explanatory variables and response variables. The results showed that 1) In 2001-2010, the amount of newly increased cultivated land obtained through land consolidation of the whole province presented a trend of significant growth, and the geographical distribution of the newly increased cultivated land was also highly concentrated. The Gini coefficient, which was 0.809 in 2001, fell straight to the lowest of 0.540 in 2009 and then rose abruptly to 0.701 in 2010. 2) Influenced by the topography and the land consolidation policy of Hubei province, the newly increased cultivated land at the county level presented obvious regional differences in 2001-2010. The cluster areas of the newly increased cultivated land at the county level changed from the mountainous areas of West Hubei to the hilly areas of East Hubei, then from the plain areas of Central Hubei to the mound areas of North Hubei over the last 10 years. 3) The source structure of the newly increased cultivated land in Hubei Province at the county level mainly included the land consolidation type, development-consolidation type and comprehensive type, while the newly increased cultivated land mainly came from land consolidation and land reclamation in Hubei province. To be more specific, most of the cultivated land in mountainous areas of Southwest Hubei, the plain areas of Central Hubei and the hilly areas of East Hubei came from land consolidation, while in the mound areas of North Hubei, from land development-consolidation. The source structure belonged to the comprehensive type in the mountainous areas of Northwest Hubei and in most counties of Huangshi, Suizhou and Xiaogan. 4) It turned out that the main impact factors and their explanatory power of the spatial-temporal pattern of the structure of the newly increased cultivated land at the county level in 2010 were as follows: cultivated land area (24.26%), topography (23.65%), project investment (19.94%), construction scale (18.16%) and per capita GDP (11.05%). It can be easily found that natural conditions and the land consolidation policy were the leading factors, while the influence of the social and economic elements was quite small in 2010. It was suggested to coordinate the relationship between ecological construction and cultivated land protection in the mound areas of North Hubei and mountainous areas of Northwest Hubei. On the premise of effective protection of the ecological environment, it was necessary to further strengthen scientific guidance and investment in the land consolidation in future in the mountainous areas of Southwest Hubei. The plain areas of Central Hubei and the hilly areas of East Hubei should actively explore the urban and rural construction land experiments, and make an overall arrangement for the planning layout of construction land and farmland to promote the new rural construction and balance urban and rural development. The results provided a scientific basis for developing the land consolidation strategy, arranging major land consolidation projects, and making differential land consolidation policies for different regions. [ABSTRACT FROM AUTHOR]

Objective: The design and development of split memory alloy sternum bone plate are discussed, and the effect of split memory alloy sternum bone plate internal fixation in the treatment of sternal fractures are analysed., Methods: The structure of the product is designed according to the anatomy and physiological characteristics of human bones, and the cross section shape of the product is designed according to the cross section shape of human bones. Internal fixation is effective in the treatment of sternal fracture., Results: The split memory alloy sternal plate was successfully designed and developed, and all the patients with sternal fractures treated by internal fixation were clinically healed, the hospitalization and fracture healing time were significantly shortened, and no obvious complications occurred., Conclusions: The application of split memory alloy sternal plate internal fixation in the treatment of sternal fracture has the advantages of small trauma, simple operation, safety, reliable fixation, good histocompatibility and less complications, and is conducive to promoting fracture healing and respiratory function improvement.

Objective: To study the effects of zeranol on spermiogenesis function of mice and its possible mechanism., Methods: 40 healthy mature male mice were randomly divided into four groups: negative group and zeranol exposure groups (25, 50, 100 mg/kg). Male mice were respectively administered with zeranol at the doses of 25, 50, and 100 mg/kg for 35 days and killed. The weights of spermary, epididymis and spermatocyst were measured. The sperm counting, motility and the percent of abnormal sperms were observed. Pathological changes of testicle tissue were also observed., Results: In comparison with control group, the visceral coefficient of spermatocysts and sperm counting of zeranol exposure groups were all decreased ( P < 0.05). Sperm motility were significantly decreased in the median and high exposure groups (P < 0.05). Pathological alterations of testes were also observed. Seminiferous epithelium was reduced in exposure groups, loose and anomalistic organization. Sperm counts were also reduced in the lumina of seminiferous tubules with glair., Conclusion: Zeranol have toxicity effect on spermigenesis function of male mice.