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Tree peony seed is unique for its super-high content of unsaturated fatty acid and is thus considered as an important source of woody oil. However, photosynthetic production is greatly reduced under high light intensity and air temperature during the seed filling period, which negatively affects seed yield and quality. The objective of this study was to determine if appropriate shading improves yield and quality of seed in oilseed peony. In this study, oilseed peony trees were shaded by different density polyethylene nets from four weeks after flowering to harvest stages to form light, moderate, and severe shadings, equivalent to about 80, 40, and 20% of full solar exposure, respectively. The effects of different shadings on some physiological parameters, yield and yield components, and nutritional composition of seed were examined. Averaged across two years, light shading increased the actual net photosynthetic rate ( P n ) by 16.8%, the maximum net photosynthetic rate ( P max ) by 81.4%, chlorophyll (Chl) content by 52.8%, auxin (IAA) content by 38.1%, and gibberellic acid (GA 3 ) content in leaves by 6.3%; it decreased the accumulation of H 2 O 2 in leaves by 24.8%, malondialdehyde (MDA) by 22%, and endogenous abscisic acid (ABA) by 8.8%, indicating that leaf senescence in late season was considerably delayed. Light shading increased seed yield, and contents of crude fat and unsaturated fatty acids by 9.7, 5.6, and 9.6%, respectively, while moderate or severe shading significantly reduced all the three parameters. Light shading increased seed weight, but moderate or severe shading reduced seed weight or follicle density. The improved seed yield under light shading was mainly due to increased seed weight, while the reduced seed yield under moderate or severe shading was mainly attributed to reduce follicle density and seed weight. The improved seed weight and content of unsaturated fatty acids under light shading was possibly due to the delayed leaf senescence. The overall results indicated that light shading is beneficial to yield and quality parameters of seed in oilseed peony. Cultivating oilseed peony under a light shading environments such as partially closed forests would better increase total output and income per unit land area than that under full solar exposure.

Objective To investigate the diagnostic value of MRI in hypertrophic pachymeningitis (HP). Methods MRI images of 11 patients with HP were analyzed retrospectively. The characteristic signs of the MRI images, and the relationship between the MRI features and pathology of HP were reviewed. Results In the 11 cases of HP, involvement of cerebral dura mater accounted for 8 cases, with spinal dura mater involvement in 2, both cerebral and spinal dura mater involvement in the other one case. The main sign of HP in MRI was an increased thickness of the dura mater, which showed iso-or hypointensity on T1WI without significant difference as compared with the brain parenchyma and spinal cord. The thickened dura mater showed obviously low signal on T2WI, and it was recognized easily as compared with the brain parenchyma and the spinal cord. On the DWI of 9 cases who had cerebral dura mater involvement, increased dura mater showed lower signal, but it was not so distinct as shown on T2WI. On the post-contrast T1WI, the thickened dura mater showed obvious enhancement, displaying better images than that of pre-enhancement image. Conclusion Among the different MRI techniques, T2-weighted imaging and post-enhanced T1WI have their advantages in the diagnosis of HP, and other MR imaging techniques could be complementary in increasing diagnostic accuracy and comprehensiveness. DOI: 10.11855/j.issn.0577-7402.2016.02.13

Acrylonitrile-butadiene-styrene (ABS) / polymethyl methacrylate (PMMA) with the addition of maleic anhydride grafted polystyrene (KT-5) and polyolefin elastomer (POE) were melt processed in a co-rotating twin-screw extruder. The effect of KT-5 and POE content on the mechanical properties of ABS/PMMA was investigated. Experiment results indicate that KT-5 can improve the tensile strength and the composites are toughened effectively as the addition of POE. According to Orthogonal tests, it demonstrates that POE ha a greater effect on the blends than KT-5, and there exist no obvious interactivity between the two components.

Ethylene methacrylate (EMA) copolymer toughened acrylonitrile-butadiene-styrene (ABS)/polymethyl methacrylate (PMMA) were prepared in a co-rotating twin-screw extruder. The effect of EMA on mechanical properties and surface gloss of ABS/PMMA blends was investigated. Experiment results show that the toughness of ABS/PMMA is improved effectively with the incorporation of EMA, while the tensile strength and glossiness decrease slightly. ABS/PMMA/EMA blends present optimum mechanical and luster properties when the content of EMA is 6wt%.

Objective To investigate the value of combined use of CT and MRI routine scan and functional imaging techniques in the follow-up process of hepatocellular carcinoma. Methods 44 cases of liver cancer patients received surgical treatment or non-surgical treatment (transcatheter hepatic arterial chemoembolization, radiofrequency ablation, and gamma-knife radiotherapy) were enrolled. All patients received CT and MR scanning for follow-up assessment after treatment. The results of conventional scanning (including CT plain scan and dynamic enhancement, MRI T1 weighted imaging, T2 weighted imaging and MR dynamic enhancement) and functional scanning (CT perfusion, MR perfusion and MRI diffusion weighted imaging) in the follow-up study of liver cancer were analysed. Out of 44 patients, the examination in 16 postoperative patients with hepatocellular carcinoma focused around the area of tumor recurrence and inflammatory reaction after surgery. In 28 patients with non-surgical treatment, the examinations focused on comprehensive assessment of activity of the lesion. Results Definite diagnosis was obtained in all of 44 patients undergoing the CT and MR conventional and functional imaging scanning. Among 16 postoperative patients with hepatocellular carcinoma, tumor recurrence at incision margin was found in 3 cases, and postoperative inflammatory reaction or abnormal focal hepatic perfusion was diagnosed in other 13 patients. As for the 28 patients with non-surgical treatment, complete tumor necrosis was found in 13, and incomplete tumor necrosis was diagnosed in 15. Conclusions CT and MR functional scan, such as CT perfusion scanning, MR DWI scan and MR perfusion scanning can be used as a beneficial supplement for routine scan and dynamic enhanced scan in follow-up assessment of liver cancer to improve diagnostic accuracy.

By cross breeding, the maize pepc gene in the pepc transgenic rice was successfully incorporated into the parents of two-, three-line hybrid rice, including sterile lines (Peiai64S, 2302S, 2304S, 2306S and Shuangjiu A) and restorer lines (5129, 02428 and Wanjing97) to breed the high-photosynthetic efficiency parents of hybrid rice and utilize heterosis between C4 and C4/C3 rice. Some lines of pepc transgenic rice (LPTR) have been developed. The study on the generations of LPTR suggests the following: (1) The segregation observed in F2 and BC1 progenies demonstrated that pepc transgene inherited as a single dominant gene in the progenies of LPTR. (2) The maize pepc gene is actively expressed at high level in LPTR, and changes of pepc gene expression in the progenies of LPTR may be related to position effect, difference of gene copy number and environmental factors. (3) Through the selection method of soaking seeds into hygromycin solution to germinate, tracing the pepc gene by PCR analysis, evaluating the performance of the rice plants in the field and examining PEPC activities, the segregation of the pepc transgene in LPTR was controlled effectively. Based on the above strategy three pepc transgene lines, H1596, H1597 and Y1470, have been selected. The result suggests that it is possible to breed practical, stable and high-expression pepc transgenic rice by conventional crossing.

The tensile deformation mechanisms of acrylonitrile – butadiene – styrene (ABS) / polymethyl methacrylate (PMMA) blends toughened by ethylene methacrylate (EMA) copolymer was investigated by analysing the fracture morphology. ABS/PMMA was blended with EMA copolymer by melt mixing technique using co-rotating twin extruder. Tensile tests show that the elongation at break of ABS/PMMA blends can be efficiently improved with the increase in EMA content. Fracture morphology of ABS/PMMA/EMA blends reveals that the material yield induced by hollowing-out of EMA particles and its propagation into yield zone is the main toughening mechanism. Moreover, the appearance that EMA particles in the central area are given priority to hollowing-out may be related to the skin-core structure of the injection moulded parts caused by the different cooling rate between surface and inside in the process of injection moulding.

To explore the influence of different compatibilizers on the strength of ABS/PMMA, two groups of tests were performed. Polymers were mixed by melt blending, and then the ternary blends were tested. SMA makes the tensile strength and impact strength of ABS/PMMA blends decrease obviously, while SBS improves the two properties except the addition of 2wt%. The results of different compatibilizers on ABS/PMMA blends were unlike.