Über die theorie benachbarter geraden und einen verallgemeinerten krümmungsbegriff; eine ergänzung zu den lehrbüchern über differentialgeometrie.

Available on demand as hard copy or computer file from Cornell University Library.

Anwendung der Differential- und Integralrechnung auf die allgemeine Theorie der Flächen und der linien doppelter Krümmung.

Available on demand as hard copy or computer file from Cornell University Library.

Analyse infinitésimale des courbes dans l'espace,

Available on demand as hard copy or computer file from Cornell University Library.

Géométrie de direction. Application des coordonnées polyédriques. Propriété de dix points de l'ellipsoïde, de neuf points d'une courbe gauche du quatrième ordre, de huit points d'une cubique gauche.

Available on demand as hard copy or computer file from Cornell University Library.

Skew frequency curves in biology and statistics.

"Erratum" slip inserted to face p. 44.

The chirurgical works of Percivall Pott, with his last corrections. : to which are added, a short account of the life of the author, a method of curing the hydrocele by injection, and occasional notes and observations /

Published in London in 1771 and 1808.

Die Spondylitis und die seitlichen Verkrümmungen der Wirbelsäule und deren Behandlung durch Suspension und Gypsverband.

Translation of spinal disease and spinal curvature.

Analytische entwickelung der raumcurve dritter ordnung aus ihren drei reellen brennstrahlen und weitere behandlung einer speciellen raumcurve dritter ordnung .. .

Mode of access: Internet.

On the nonlinear Neumann problem involving the critical Sobolev exponent on the boundary

in this paper we investigate the solvability of the Neumann problem (1.1) involving the critical Sobolev exponents on the right-hand side of the equation and in the boundary condition. It is assumed that the coefficients Q and P are smooth. We examine the common effect of the mean curvature of the boundary a deltaOhm and the shape of the graph of the coefficients Q and P on the existence of solutions of problem (1.1). (C) 2003 Published by Elsevier Inc.

Van der Waals-corrected density functional theory: benchmarking for hydrogen-nanotube and nanotube-nanotube interactions

Density functional theory (DFT) is a powerful approach to electronic structure calculations in extended systems, but suffers currently from inadequate incorporation of long-range dispersion, or Van der Waals (VdW) interactions. VdW-corrected DFT is tested for interactions involving molecular hydrogen, graphite, single-walled carbon nanotubes (SWCNTs), and SWCNT bundles. The energy correction, based on an empirical London dispersion term with a damping function at short range, allows a reasonable physisorption energy and equilibrium distance to be obtained for H-2 on a model graphite surface. The VdW-corrected DFT calculation for an (8, 8) nanotube bundle reproduces accurately the experimental lattice constant. For H-2 inside or outside an (8, 8) SWCNT, we find the binding energies are respectively higher and lower than that on a graphite surface, correctly predicting the well known curvature effect. We conclude that the VdW correction is a very effective method for implementing DFT calculations, allowing a reliable description of both short-range chemical bonding and long-range dispersive interactions. The method will find powerful applications in areas of SWCNT research where empirical potential functions either have not been developed, or do not capture the necessary range of both dispersion and bonding interactions.

Microfluidic interferometer

We present a class of compact, fluid-based, interferometric, tunable optical components: the single-beam microfluidic Mach-Zender interferometer. Phase delay is achieved through light propagation across a fluid-air interface (meniscus). The effect of meniscus curvature on the device transmission is considered using the three-dimensional beam propagation method and shown to be an important device parameter. We engineer the meniscus curvature using monomer surface chemistry, rendering it flat, and find that the experimental response corresponds well with simulation. The device has a resonance at 1.3 mum with a 25 dB extinction ratio; the latter can be adjusted by shifting the meniscus position.

Sharp Sobolev inequality involving a critical nonlinearity on a boundary

We consider the solvability of the Neumann problem for the equation -Delta u + lambda u = 0, partial derivative u/partial derivative v = Q(x)vertical bar u vertical bar(q-2)u on partial derivative Omega, where Q is a positive and continuous coefficient on partial derivative Omega, lambda is a parameter and q = 2(N - 1)/(N - 2) is a critical Sobolev exponent for the trace embedding of H-1(Omega) into L-q(partial derivative Omega). We investigate the joint effect of the mean curvature of partial derivative Omega and the shape of the graph of Q on the existence of solutions. As a by product we establish a sharp Sobolev inequality for the trace embedding. In Section 6 we establish the existence of solutions when a parameter lambda interferes with the spectrum of -Delta with the Neumann boundary conditions. We apply a min-max principle based on the topological linking.

Variability in Cobb angle measurements using reformatted computerized tomography scans

Study Design. Survey of intraobserver and interobserver measurement variability. Objective. To assess the use of reformatted computerized tomography (CT) images for manual measurement of coronal Cobb angles in idiopathic scoliosis. Summary of Background Data. Cobb angle measurements in idiopathic scoliosis are traditionally made from standing radiographs, whereas CT is often used for assessment of vertebral rotation. Correlating Cobb angles from standing radiographs with vertebral rotations from supine CT is problematic because the geometry of the spine changes significantly from standing to supine positions, and 2 different imaging methods are involved. Methods. We assessed the use of reformatted thoracolumbar CT images for Cobb angle measurement. Preoperative CT of 12 patients with idiopathic scoliosis were used to generate reformatted coronal images. Five observers measured coronal Cobb angles on 3 occasions from each of the images. Intraobserver and interobserver variability associated with Cobb measurement from reformatted CT scans was assessed and compared with previous studies of measurement variability using plain radiographs. Results. For major curves, 95% confidence intervals for intraobserver and interobserver variability were +/- 6.6 degrees and +/- 7.7 degrees, respectively. For minor curves, the intervals were +/- 7.5 degrees and +/- 8.2 degrees, respectively. Intraobserver and interobserver technical error of measurement was 2.4 degrees and 2.7 degrees, with reliability coefficients of 88% and 84%, respectively. There was no correlation between measurement variability and curve severity. Conclusions. Reformatted CT images may be used for manual measurement of coronal Cobb angles in idiopathic scoliosis with similar variability to manual measurement of plain radiographs.

Application of a generalized thermodynamic approach to characterize mesoporous materials

Equilibrium adsorption and desorption in mesoporous adsorbents is considered on the basis of rigorous thermodynamic analysis, in which the curvature-dependent solid-fluid potential and the compressibility of the adsorbed phase are accounted for. The compressibility of the adsorbed phase is considered for the first time in the literature in the framework of a rigorous thermodynamic approach. Our model is a further development of continuum thermodynamic approaches proposed by Derjaguin and Broekhoff and de Boer, and it is based on a reference isotherm of a non-porous material having the same chemical structure as that of the pore wall. In this improved thermodynamic model, we incorporated a prescription for transforming the solid-fluid potential exerted by the flat reference surface to the potential inside cylindrical and spherical pores. We relax the assumption that the adsorbed film density is constant and equal to that of the saturated liquid. Instead, the density of the adsorbed fluid is allowed to vary over the adsorbed film thickness and is calculated by an equation of state. As a result, the model is capable to describe the adsorption-desorption reversibility in cylindrical pores having diameter less than 2 nm. The generalized thermodynamic model may be applied to the pore size characterization of mesoporous materials instead of much more time-consuming molecular approaches. (c) 2005 Elsevier B.V. All rights reserved.