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Highlights: [•] The lowest-energy structures of the Ni n Mn (n =1–12) clusters are obtained using all-electron DFT-GGA calculations. [•] The magnetic moments are enhanced on substituting one Ni atom by one Mn atom in the Ni n+1 (n =1–9, 11 and 12) clusters. [•] The Ni3Mn, Ni5Mn, Ni8Mn and Ni10Mn clusters are found to be more stable than their neighbors. [•] The magnetic moment surface enhancement effect can be demonstrated from the magnetic properties of the doped Mn atom. [Copyright &y& Elsevier]

Objective: To evaluate the application value of multiple phase subtraction imaging of dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) in common breast tumor., Methods: All radiographic and MRI data of 72 patients with histological proved common breast tumor were analyzed retrospectively. Prior to an injection of gadolinium-diethylenetriaminepentaacetate (GD-DTPA), 3D mask scans were performed. Then 9 consecutive phases of imaging were acquired. After the drawing of time-signal intensity curve, he first and second phases were selected to perform subtraction with the mask, rebuild 3D maximum intensity projection and analyze the application value of subtracted and 3D maximum intensity projection (MIP) reformation images. Chi-square test was used for the analyses of benign and malignant breast tumors., Results: There were 83 lesions in 72 patients. Among 18 cases of fibro adenoma, 23 lesions had no tumor vessel. For the detecting ratio of lesions, the first and second phase subtraction imaging had no statistics difference. Only one intraductal papilloma with ductal carcinoma in situ (DCIS) had tumor vessel in 4 intraductal papilloma patients. Among 5 DCIS cases, one of them had small curved tumor vessel. And 51 lesions were found in 45 infiltrating ductal carcinoma (IDC) cases. Tumor vessels could be seen in all IDC cases. And 37 cases had multiple tumor vessels while 8 cases had single tumor vessel. When the first phase was used for subtraction, 36 lesions were found. On the other hand, 51 lesions were found in the second phase subtraction. There were significant differences between them., Conclusion: No significant differences exist in benign breast tumor on differential phase subtraction images of DCE-MRI, but there are significant differences in malignant breast tumor. It is very important to detect the lesions and show the tumor vessels by rebuilding multiple phase subtraction.