1,721,718 research outputs found
Facial retaining ligaments based on real color sectioned images with 3D models: Toward a more precise classification
No full textFacial retaining ligaments play a crucial role in maintaining and supporting skin with the superficial musculoaponeurotic system. However, visualizing these ligaments in detail has been challenging due to the limitations of cadaver dissection and radiologic images for plastic surgery. This study aims to visualize and refine the anatomical definitions of the facial retaining ligaments using high-resolution, true-color sectioned images and three-dimensional models. Facial retaining ligaments with their neighboring structures were identified in the sectioned images and reconstructed into 3D models. Using these sectioned images and 3D models, the ligaments were anatomically analyzed alongside neighboring structures. The study revealed distinct morphological features of the retaining ligaments (orbital retaining ligament with the lateral orbital thickening, zygomatic ligament, maxillary ligament, platysma-auricular ligament, masseteric ligament, mental ligament, medial mandibular ligament, mandibular osteocutaneous ligament, cervicomental angle suspensory ligament), including their orientation relative to the skin and their role in anchoring SMAS and adjacent tissues on the real color datasets. These findings enhance our understanding of facial anatomy and offer valuable insights for surgical planning and safer aesthetic procedures. This approach demonstrates the potential of high-resolution anatomical imaging as a superior alternative to traditional dissection and grayscale radiologic imaging
Plasma-enhanced ALD of titanium-silicon-nitride using TiCl4, SiH4, and N-2/H-2/Ar plasma
No full textThin films of Ti-Si-N were deposited by plasma-enhanced atomic layer deposition (PEALD) using TiCl4, SiH4, and N-2 /H-2 /Ar radicals at 350degreesC. When the reactants were supplied in the sequence of TiCl4 pulse, SiH4 pulse, then N-2 /H-2 /Ar plasma, the thickness per cycle and Si content in Ti-Si-N thin film saturated at 0.73 Angstrom/cycle and 8.5 atom % (Cl less than or equal to 0.5 atom %), respectively. The thickness per cycle is different from that of metallorganic ALD (MOALD). Although X-ray diffraction did not detect the presence of silicon nitride, the silicon nitride phase was investigated by electron spectroscopy for chemical analysis. The addition of Si in Ti-Si-N thin films results in increased resistivity (approximately 500 muOmega cm) and improved Cu diffusion barrier properties due to the Si3N4 phase. (C) 2004 The Electrochemical Society.Korea Advanced Institute of Science and Technology assisted in meeting the publication costs of this article
A capacitive absolute-pressure sensor with external pick-off electrodes
No full textThis paper describes a capacitive absolute-pressure sensor in which the sealed lead transfer is eliminated. The pick-off capacitance is between a flap or skirt-like extension of the flexible diaphragm that reaches past the sealed cavity, and an electrode patterned on the substrate directly below this extension. The sidewall of the cavity is relatively narrow and flexible. Finite-element analysis is used to explore the relevance of various dimensional parameters and to estimate the sensitivity and temperature coefficients of the device. The device is fabricated from p(++) Si on a glass substrate using the dissolved wafer process with three masking steps. The measurements of fabricated devices with 1 mm radius, 7 mum cavity height, and 8 mum wall thickness show -84 ppm kPa(-1) sensitivity at room temperature in touch-mode operation. In non-touch-mode operation the sensitivity is significantly higher. A reference device with similar dimensions shows a less than 22 ppm K-1 temperature coefficient of offset below 150 degreesC.X111210sciescopu
A servo-controlled capacitive pressure sensor using a capped-cylinder structure microfabricated by a three-mask process
No full textA silicon-micromachined servo-controlled capacitive pressure sensor is described. The use of a capped-cylinder shape with pick-off electrodes external to a sealed cavity permits this device to be fabricated in only three masking steps. Device behavior is evaluated experimentally and by finite element analysis. A fabricated device with 2 mm diameter, 9.7 mum structural thickness and 10 mum cavity height provides a measured sensitivity of 0.516 V/kPa over a dynamic range of 20-100 kPa gauge pressure, with a nonlinearity of <3.22% of full scale. The open-loop sensitivity of this device averaged over a dynamic range of 0-250 kPa is -408 ppm/kPa. A voltage bias applied to the servo-electrode can be used to tune both the open-loop and servo-controlled sensitivity by more than 30%. An alternative design in which the Si electrode is segmented to relieve residual stress provides 10-20% more open-loop sensitivity with similar structural dimensions. Fabricated devices are sealed within a metal package filled with an inert dielectric liquid. This enhanced open-loop sensitivity by a factor of about 1.7, and in servo-controlled operation, reduced restoring voltage by a similar factor. Measurements and analysis of temperature responses of these devices are presented.X111317sciescopu
Deformations of coisotropic submanifolds and strong homotopy Lie algebroids
No full textIn this paper, we study deformations of coisotropic submanifolds in a symplectic manifold. First we derive the equation that governs C-infinity deformations of coisotropic submanifolds and define the corresponding C-infinity-moduli space of coisotropic submanifolds modulo the Hamiltonian isotopies. This is a non-commutative and non-linear generalization of the well-known description of the local deformation space of Lagrangian submanifolds as the set of graphs of closed one forms in the Darboux-Weinstein chart of a given Lagrangian submanifold. We then introduce the notion of strong homotopy Lie algebroid (or L-infinity-algebroid) and associate a canonical isomorphism class of strong homotopy Lie algebroids to each pre-symplectic manifold (Y,omega) and identify the formal deformation space of coisotropic embeddings into a symplectic manifold in terms of this strong homotopy Lie algebroid. The formal moduli space then is provided by the gauge equivalence classes of solutions of a version of the Maurer-Cartan equation (or the master equation) of the strong homotopy Lie algebroid, and plays the role of the classical part of the moduli space of quantum deformation space of coisotropic A-branes. We provide a criterion for the unobstructedness of the deformation problem and analyze a family of examples that illustrates that this deformation problem is obstructed in general and heavily depends on the geometry and dynamics of the null foliation.X112524Nsciescopu
Transient Stewartson layers of a rotating compressible fluid
No full textAn analysis of the azimuthal velocity (v) structure in transient Stewartson layers of a rapidly rotating compressible fluid is made. The specific problem formulation is for the case when the rotating sidewall of a cylindrical container is given a small impulsive increase in rotation rate. A two-variable matched asymptotic technique is employed to describe the azimuthal velocity in the Stewartson layer. The Laplace transforms are applied to obtain an approximate analytical solution for v. This solution at large times is consistent with the previously established steady-state behavior. Also, when the fluid compressibility vanishes, this solution recovers the features of incompressible-fluid flows. When the compressibility effect is appreciable, the influence of the local viscosity effect becomes noticeable, and the thicknesses of boundary layers increase. At a given radial location, with the increase of the compressibility effect, the magnitude of v becomes larger. The impact of the compressibility effect is to shorten the transitory time needed to reach the steady state. These results are in qualitative agreement with the assertions of the preceding studies
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