Breast metastasis and lung large-cell neuroendocrine carcinoma: first clinical observation

The lung Large-cell neuroendocrine carcinoma (LCNEC) is a very rare aggressive neuroendocrine tumor with a high propensy to metastasize and very poor prognosis. We report an atypical presentation of lung large-cell neuroendocrine carcinoma was diagnosed from a metastatic nodule on the breast. Our patient is a 59 years-old woman that presented in March 2014 non productive cough. A CT scan showed multiple brain, lung, adrenal gland and liver secondary lesions; moreover, it revealed a breast right nodule near the chest measuring 1.8 cm. The breast nodule and a lung lesions were biopsied and their histology and molecular diagnosis were LCNEC of the lung. To our knowledge, this is the first documented case of breast metastasis from LCNEC of the lung. Furthermore, breast metastasis from extramammary malignancy is uncommon and its diagnosis is difficult but important for proper management and prediction of prognosis. Therefore, a careful clinical history with a thorough clinical examination is needed to make the correct diagnosis. Moreover, metastasis to the breast should be considered in any patient with a known primary malignant tumor history who presents with a breast lump. Anyhow, pathological examination should be performed to differentiate the primary breast cancer from metastatic tumor. Therefore, an accurate diagnosis of breast metastases may not only avoid unnecessary breast resection, more importantly it is crucial to determine an appropriate and systemic treatment

Plastic deformations in crystal, polycrystal, and glass in binary mixtures under shear: Collective yielding

Using molecular dynamics simulation, we examine the dynamics of crystal, polycrystal, and glass in a Lennard-Jones binary mixture composed of small and large particles in two dimensions. The crossovers occur among these states as the composition c is varied at fixed size ratio. Shear is applied to a system of 9000 particles in contact with moving boundary layers composed of 1800 particles. The particle configurations are visualized with a sixfold orientation angle alpha_j(t) and a disorder variable D_j(t) defined for particle j, where the latter represents the deviation from hexagonal order. Fundamental plastic elements are classified into dislocation gliding and grain boundary sliding. At any c, large-scale yielding events occur on the acoustic time scale. Moreover, they multiply occur in narrow fragile areas, forming shear bands. The dynamics of plastic flow is highly hierarchical with a wide range of time scales for slow shearing. We also clarify the relationship between the shear stress averaged in the bulk region and the wall stress applied at the boundaries.Comment: 17 pages, 15 figures, to appear in Physical Review

Effect of composition on the mechanical properties of newly developed Ti<SUB>2</SUB>AlNb-based titanium aluminide

Among titanium aluminides Ti2AlNb-based alloys have received considerable attention in recent years, as potential materials for high-temperature applications in jet engines. Several compositions based on Ti-22Al-25Nb with molybdenum, silicon, zirconium additions were developed. The investigated microstructures consist of bi-lamellar O-Ti2AlNb structure with α2-Ti3Al nodules, surrounded by a B2 matrix. Effects of Aluminium and Niobium contents are, especially, examined on tensile properties, on creep strength and on oxidation resistance. It is shown that a high Al/Nb ratio is required for a good oxidation resistance, but is associated with a loss of ductility. Reducing Nb results in a decrease of creep strength that can be compensated by zirconium and/or molybdenum additions which improve the creep resistance significantly without impairing ductility or yield stress

Microstructure and mec-hanical properties of orthorhombic alloys in the Ti-Al-Nb system

The current understanding of the metallurgy of the orthorhombic alloys in the Ti-Al-Nb system is reviewed with emphasis on tensile and creep properties of ternary alloys. It is shown that increasing the Nb content of alloys from 15 to 27 at% at a constant Al level significantly increases both the tensile and creep properties of equiaxed as well as lath structures, while small changes in Al content have a large effect on creep. For a given alloy composition, the amount of B2(β) phase and its distribution and the scale of O laths influences tensile properties, while creep properties depend on the volume fraction of equiaxed α2/O phase present in the structure as well as the size of O laths