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We describe an ultrafast transition of the electronic response of optically excited transition metal β-tungsten with few-femtosecond time resolution. The response moves from a regime where state filling of the excited carrier population around the Fermi level dominates towards localization of carriers onto the outer d orbitals. This is in contrast to previous measurements using ultrafast element-specific core-level spectroscopy enabled by attosecond transient absorption spectroscopy on transition metals such as titanium and around the transition metal atom in transition metal dichalchogenides MoTe_{2} and MoSe_{2}. This surprisingly different dynamical response for β-tungsten can be explained by considering the electron-electron dynamics on a few-femtosecond timescale and the slower electron-phonon thermalization dynamics.

In this study we assessed the expression of the Melan-A/MART-1 antigen by immunohistochemistry using monoclonal antibody A103 in 73 primary cutaneous melanomas and its correlation with tumor staging and patient survival. Melan-A/MART-1 was expressed in 90% of primary tumors, with loss of expression increasing with Breslow thickness. Kaplan-Meier analysis demonstrated a significantly reduced disease-free interval and overall survival rate for patients not expressing this antigen. The poor prognosis of such patients was even worse for those presenting with a primary melanoma and a Breslow thickness of > or = 1 mm. Thus, Melan-A/MART-1 is not only a useful and specific additional marker for the diagnosis of primary cutaneous melanoma, but it may also help refine the prognosis of patients with malignant melanoma., (Copyright 2001 Wiley-Liss, Inc.)

Flow cytometry offers a relatively simple method to determine the DNA content of colorectal cancers. However, the technique can not discover minor changes in karyotype which may characterize near-diploid tumors, nor will it detect very small populations of aneuploid cells. In an attempt to improve the detection of such cells, we incubated biopsy material prior to analysis. This method revealed an aneuploid subpopulation in one of two biopsies studied. This simple protocol may ultimately lead to a more accurate assessment of the ploidy in colon cancer.