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Spontaneous regression of metastatic malignant melanoma is rare. A case is presented here. The primary lesion, a lentigo maligna melanoma of the face, recurred after excision and metastasized to the parotid and upper cervical lymph nodes, and to the lungs. The patient declined further therapy. There was no clinical or radiologic evidence of metastasis 1 year later.
Roland Barthes is best known as a literary critic and essayist and as a member of that generation of internationally distinguished French intellectuals (maîtres à penser) that includes the philosopher/historian Michel Foucault, the psychoanalyst Jacques Lacan, and the anthropologist Claude Lévi-Strauss. ...
Many aspects of the coupling between vocal fold motion, glottal airflow, and resulting sound waves remain unexplored, particularly during incomplete glottal closure. In addition, this coupling has been associated with distortions in the estimates of glottal parameters obtained from neck acceleration measurements, thus affecting the ambulatory assessment of vocal function. This acoustic coupling and its effects on inverse filtering of oral airflow and neck surface acceleration during vowel production were investigated using numerical and experimental methods. A lumped element self-oscillating model was extended to include different types of incomplete glottal closure, which provided an enhanced simulation tool that mimicked normal and hyperfunctional voices. Novel in vivo measurements and analyses of vocal fold tissue instabilities due ...
Mathematical models of human voice production are widely used in research to study the underlying acoustic mechanisms of phonation. While existing models can recreate the anatomical structures of the supraglottal system (upper respiratory airways) and the vocal folds with realistic detail, they ignore or oversimplify the branching anatomical complexity of the subglottal system (lower respiratory airways) and the acoustic properties associated with this system. Consequently, current modeling techniques fail to incorporate the acoustic contributions of the subglottal system in an anatomically-relevant manner. In this thesis research, a time-domain numerical framework for modeling sound wave propagation in the branching airway generations of the subglottal system was formulated and incorporated into a general scheme of voice production. T...
Respiratory monitoring during athletic activity or other clinical and occupational settings would benefit from a method that does not obstruct the airway. Previous studies have demonstrated the utility of breath sound measurements performed on the chest or neck to detect airflow. This dissertation investigates a novel location for breath sound measurements: the external ear. In all of the experiments, a miniature electret microphone, set within a disposable rubber earplug, was placed in each subject's external acoustic meatus. The first experiment demonstrated the passive transmission of sound from the oropharynx to the external ear in nineteen adults. Broadband noise was introduced to each subject's pharynx via a tubular mouthpiece and was recorded by both an accelerometer affixed to the subject's cheek and the ear microphone. Near-un...
This dissertation has two objectives; the first is to investigate speciation of three d10 metals (Ag(I), Hg(II) and Pb(II)) in sulfidic solutions containing As(III) to determine if thioarsenite could act as a ligand for the metals. Second, a hypothesis that As(III) forms strong complexes with bicarbonate is investigated. The solubility of As in sulfidic solutions (10-4-10-3 M) equilibrated with As2S3+S at near-neutral pH (6.95-7.95) was measured and compared to the solubility of As in binary and ternary assemblages. Three species, AsS(HS)(OH)-, As(OH)3 and H2As3S6-, explain As speciation: 0.5As2S3 + 3H2O  As(OH)3 + 1.5H2S, pK=12.58, 1.5As2S3 + 1.5H2S  H2As3S6- + H+, pK=6.200.77 and 0.5As2S3 + H2O + 0.5H2S AsS(HS)(OH)- + H+ pK=8.740.09. The solubility of As and Ag in sulfid...
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