VUV photo-ionization parameters and effective mean free path of epithermal photoelectrons in pure non-polar dielectric liquids

VUV photo-ionization spectra of cyclohexane, 2,2 dimethylbutane, tetramethylsilane and polydimethylsiloxane oils were experimentally obtained, using a new experimental set-up. Power laws for photocurrent were observed and photoionization thresholds, confirming our previous data, were deduced. Using a 3-parameter adjustment method and Onsager theory, parameters specific of photoionization process were extracted from curves giving the photocurrent as a function of an applied electric field, at photon excess energies between 0.5 eV and 2 eV above the corresponding ionization thresholds. Assuming the range distribution function of thermalized photoelectrons to be a modified exponential function, called PE3, an effective mean free path along the thermalization path in each liquid was deduced from B/sub 3/, the experimental range parameter associated with the range distribution function. These mean free path values, at the epithermal stage, were compared to those of the thermal mean free path of conduction electrons.     

Non linear behavior of vocal fold vibration in an experimental model of asymmetric larynx: role of coupling between the two folds

Morphometric evaluation of 54 dry cervical spines from C3 to C7 (a total of 270 cervical vertebrae) was performed to determine the bony boundaries of the uncinate process for resection of the uncinate process for access to posterolateral osteophytes or herniated disks at the time of anterior cervical diskectomy. The uncinate processes were significantly higher (p < 0.01) at the C4-C6 levels (5.8 +/- 1.1 mm to 6.1 +/- 1.3 mm) than at the C3 or C7 levels. The distance between the medial and lateral margins of the base of the uncinate process was significantly smaller (p < 0.01) at the C3 level (4.9 +/- 0.7 mm) than at the C7 level (6.3 +/- 0.7 mm). The anteroposterior diameter of the medial margin of the uncinate process decreased gradually from the C5 (12.5 +/- 1.5 mm) to C7 levels (11.6 +/- 1.3 mm) (p < 0.05). The inter-uncinate distance widened from the C3 (19.2 +/- 1.5 mm) to the C7 (24.6 +/- 2.1 mm) levels (p < 0.01). The mid-anteroposterior diameter of vertebral body increased gradually from the C3 (14.7 +/- 1.1 mm) to the C7 levels (16.1 +/- 1.5 mm) (p < 0.01). The width of the vertebra increased gradually from C3 to C7 (from 19.2 +/- 1.8 mm at C3 to 25.6 +/- 2.0 mm at C7) (p < 0.01). Knowledge of all the aforementioned data may be helpful during anterolateral cervical uncosectomy or uncoforaminotomy.