Melanoma’s sentinel node biopsy: comparison between two clinical hospitals over 5 years

University of Medicine and Pharmacy of Targu Mures, Romania, University Hospital of Parma, ItalyIntroduction. Sentinel lymph node (SLN) is defined as the first lymph node localized on the direct lymphatic drainage pathway from a primary tumor. The sentinel lymph node biopsy (SLNB) is largely used in breast cancer and melanoma but it may also be useful in other epithelial skin cancers as well as in tumors located in the upper or lower gastrointestinal tract, lungs, thyroid, cervix and vulva. SLNB in melanoma is essential for an accurate staging, to estimate the risk of extension to other lymph nodes or organs and to evaluate the prognosis. Melanoma, even if it is not as common as the basal cell carcinoma or squamous cell carcinoma among the skin tumors, presents an increasing incidence and a higher mortality

Localization-enhanced biexciton binding in semiconductors

The influence of excitonic localization on the binding energy of biexcitons is investigated for quasi-three-dimensional and quasi-two-dimensional AlxGa1−xAs structures. An increase of the biexciton binding energy is observed for localization energies comparable to or larger than the free biexciton binding energy. A simple analytical model for localization in the weak confinement regime ascribes the increase to a quenching of the additional kinetic energy of the exciton-exciton motion in the biexciton

Transient four-wave mixing in T-shaped GaAs quantum wires

The binding energy of excitons and biexcitons and the exciton dephasing in T-shaped GaAs quantum wires is investigated by transient four-wave mixing. The T-shaped structure is fabricated by cleaved-edge overgrowth, and its geometry is engineered to optimize the one-dimensional confinement. In this wire of 6.6×24 nm2 size, we find a one-dimensional confinement of more than 20 meV, an inhomogeneous broadening of 3.4 meV, an exciton binding energy of 12 meV, and a biexciton binding energy of 2.0 meV. A dispersion of the homogeneous linewidth within the inhomogeneous broadening due to phonon-assisted relaxation is observed. The exciton acoustic-phonon-scattering coefficient of 6.1±0.5 μeV/K is larger than in comparable quantum-well structures