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This paper is concerned with a partially observed optimal control problem described by mean-field forward and backward stochastic differential equations. Moreover, the control variable enters the diffusion coefficient and the control domain is non-convex. Utilising Girsanov's theorem as well as extended Ekeland's variational principle, a maximum principle is established in the form of Pontryagin's type. As an application, a linear-quadratic control problem is studied in terms of the stochastic filtering. [ABSTRACT FROM AUTHOR]

The authors consider a mixed super quasi-Einstein manifold, which is conducive to understanding deeply the global characteristics of the universe including its topology. Firstly, the existence of such manifolds is ensured by an interesting example. Then, the authors determine the curvature characterizations of a class of mixed super quasi-Einstein manifolds. Finally, the present paper depicts a W 2 -conservative characteristic of mixed super quasi-Einstein manifolds associated with a recurrent generator. [ABSTRACT FROM AUTHOR]

Seaweed and its derivatives are widely used as nutrient supplements, biofertilizers, and biostimulants for soil in agriculture. The aim of this study was to evaluate the effects of seaweed fertilizer on the growth of apple ( Malus hupehensis Rehd.) seedlings under replant conditions. We investigated the growth of apple seedlings in replant soil treated with seaweed fertilizer at application rates of 0, 5, 20, and 40 g kg −1 . The addition of seaweed fertilizer significantly increased the plant height and dry weight of apple seedlings. Seedlings grown in soil treated with seaweed fertilizer, particularly the dose of 40 g kg −1 soil showed higher activities of antioxidant enzymes including superoxide dismutase, peroxidase and catalase, which was accompanied by lower malondialdehyde accumulation. The activities of soil enzymes (invertase, urease, proteinase and phosphatase) were higher in soil treated with seaweed fertilizer than in control soil. An analysis of terminal restriction fragment length polymorphism profiles showed that the fungal communities differed markedly between the 40 g kg −1 seaweed fertilizer treatments and the 0, 5, and 20 g kg −1 treatments. The highest values of Shannon diversity index, evenness index and richness index were in the 40 g kg −1 seaweed fertilizer treatments, and the lowest values of these indexes were in the control. These results suggested that seaweed fertilizer application at a dose of 40 g kg −1 can improve soil enzymes activities, change the soil fungal communities, and improve soil quality. These changes can promote seedlings growth, increase antioxidant activity, and decrease lipid peroxidation in roots, thereby alleviating apple replant disease. [ABSTRACT FROM AUTHOR]

Objective: To investigate hematopoiesis and cytogenetics changes in staff of interventional radiology. Methods: A total of 121 intervention radiation workers, 245 common radiation workers and 100 medical personnel (healthy control) without exposure to radiation were enrolled in the study. The peripheral lymphocyte chromosomal aberrations and micronucleus were detected, and the result of white blood cells examination was analyzed. Results: Compared with common radiation group and healthy control group, decreases in white blood cells count, neutrophil ratio, and increase in lymphocyte ratio were observed in intervention radiation group (all P <0.05). Intervention radiation group had higher chromosome aberration rate and micronuclear rate than common radiation group and healthy control group (all P <0.05). Most common chromosome aberrations were dicentric chromosome, acentric ring, fragments and minute chromosome. Abnormal rates in chromosome aberration and micronucleus rates were increased with the rise of length of service, but no statistically significant difference was observed ( P >0.05). Conclusion: Long term exposure to ionizing radiation may lead to changes in the human hematopoietic system and cause human chromosome aberration, and the severity of such injuries may be associated with the dose of ionizing radiation.