Contour Profiles Research Articles

Wavelet Packet Fractal Analysis of Neuronal Morphology

An image analysis method called two-dimensional wavelet packet analysis (2D WPA) is introduced to quantify branching complexity of neurons. Both binary silhouettes and contour profiles of neurons were analyzed to determine accuracy and precision of the fractal dimension in cell classification tasks. Two-dimensional WPA plotted the slope of decay for a sorted list of discrete wavelet packet coefficients belonging to the adapted wavelet best basis to obtain the fractal dimension for test images and binary representations of neurons. Two-dimensional WPA was compared with box counting and mass-radius algorithms. The results for 2D WPA showed that it could differentiate between neural branching complexity in cells of different type in agreement with accepted methods. The importance of the 2D WPA method is that it performs multiresolution decomposition in the horizontal, vertical, and diagonal orientations.

Diffusion in the Presence of Grain Boundaries: a Variable Length Scale Simulation Method

ABSTRACTIn this paper we introduce a Monte Carlo method for numerical analysis of the problem of tracer diffusion in the presence of isolated grain boundaries with a variable mesh in the direction perpendicular to the grain boundary plane. A number of isoconcentration contour profiles were studied. Two different expressions for the angle between the isoconcentration contours and the grain boundary were derived for the instantaneous tracer source following procedures analogous to Fisher's and Whipple's approximations for the constant tracer source. Comparison with the numerical data was made. Both these approximations overestimate the grain boundary diffusivity.

An approach to form deviation evaluation for CMM measurement of 2D curve contours

In this paper, a practical approach towards evaluating form deviations of 2D curve contour profiles based on discrete coordinate measurement data is proposed. Using this approach, the evaluation precision of the form deviation can be sufficiently guaranteed. The approach is easy and convenient for engineering applications. A practical evaluation example for a planar cam profile is also shown. All of the form deviations of the cam profile obtained by the minimum zone criterion (MZC) satisfy the geometrical condition of the MZC resolution and are obviously smaller than those obtained by the least square criterion.

Application of gravity and magnetic methods to assess geological hazards and natural resource potential in the Mosida Hills, Utah County, Utah

Gravity and magnetic data were collected in the Mosida Hills, Utah County, Utah, at over 1100 stations covering an area of approximately 58 km2(150 mi2) in order to help define the subsurface geology and assess potential geological hazards for urban planning in an area where the population is rapidly increasing. In addition, potential hydrocarbon traps and mineral ore bodies may be associated with some of the interpreted subsurface structures. Standard processing techniques were applied to the data to remove known variations unrelated to the geology of the area. The residual data were used to generate gravity and magnetic contour maps, isometric projections, profiles, and subsurface models. Ambiguities in the geological models were reduced by (1) incorporating data from previous geophysical surveys, surface mapping, and aeromagnetic data, (2) integrating the gravity and magnetic data from our survey, and (3) correlating the modeled cross sections. Gravity highs and coincident magnetic highs delineate mafic lava flows, gravity lows and magnetic highs reflect tuffs, and gravity highs and magnetic lows spatially correlate with carbonates. These correlations help identify the subsurface geology and lead to new insights about the formation of the associated valleys. At least eight new faults (or fault segments) were identified from the gravity data, whereas the magnetic data indicate the existence of at least three concealed and/or poorly exposed igneous bodies, as well as a large ash‐flow tuff. The presence of low‐angle faults suggests that folding or downwarping, in addition to faulting, played a role in the formation of the valleys in the Mosida Hills area. The interpreted location and nature of concealed faults and volcanic flows in the Mosida Hills area are being used by policy makers to help develop mitigation procedures to protect life and property.

Ni:LiNbO3 Ridge Waveguide Mach-Zehnder Electrooptic Modulators Fabricated by Proton-exchanged Wet Etching

Investigations into the effects of ridge heights on the characteristics, including the optical contour profiles and driving voltages, of Ni:LiNbO 3 ridge waveguide Mach-Zehnder electrooptic modulators have been carried out successfully. Mach-Zehnder electrooptic modulators with different ridge heights were fabricated by the proton-exchanged (PE) wet etching technique, including that of the PE wet etching prior to Ni indiffusion and the novel self-aligned process. For both processes, it has been concluded that the driving voltage of the modulators can be significantly reduced by increasing the ridge height, and the corresponding effect on the optical contour profile has also been demonstrated.

A practical evaluation approach towards form deviation for two-dimensional contours based on coordinate measurement data

A precise evaluation of the form deviations of two-dimensional (2D) engineering contours is of essential importance in precision manufacturing. In this paper, we propose a practical approach towards evaluating form deviations of 2D contour profiles based on coordinate measurement data. Using this approach, a 2D contour is divided into straight and curved parts. Each straight part is directly presented by the original definition of the part; and each curved part is further represented by its optimal interpolation circular arc segments whose interpolation accuracy can be specified arbitrarily. The approximate contour curve consisting of the straight and circular arc segments has the fewest interpolation segments under the condition of satisfying the pre-specified interpolation accuracy. The form deviation of a measured point is defined as the distance from the point to its corresponding straight or circular segment. The geometrical form deviation of the contour profile is evaluated using the least square method. It has been demonstrated that the difference between the deviation definitions, relative to the original contour or to the approximate contour, is not larger than the pre-specified accuracy value for circular arc interpolation. Therefore, the evaluation precision of the form deviation can be sufficiently guaranteed. The approach is easy and convenient for engineering applications. The effectiveness and the efficiency of the approach are verified with a practical example of a planar cam contour in the paper.

Transient Natural Convection Between Vertical Finite Length Heated Plates

A numerical analysis of transient natural convection in vertical finite length plates with transient symmetric isoflux heating has been performed. The parameters studied are Prandtl number 0.7, channel aspect ratio 5, and steady-state Grashof numbers ranging from 10 to 10 8 . Transient thermal and flowfields, including isotherms, pressure contour, streamlines, and velocity profiles for various steady-state Grashof numbers are also presented and discussed. A new composite correlation of a transient-induced Reynolds number for a vertical finite length channel with various transient Rayleigh numbers is proposed.

Numerical simulation of natural convection of gallium in a narrow gap

Natural convection in a low Prandtl number, liquid metal gallium was numerically simulated in a 2 mm narrow gap test cell to benchmark experiments. One two-dimensional model and three different three-dimensional models were tested using a commercial finite element code and compared to an X-ray visualization experiment. Significant differences were found between the results obtained in the two-dimensional and individual three-dimensional models. The inclusion of the bounding solid walls of the test cell in the three-dimensional model resulted in temperature contour profiles which are comparable to the experimental visualization in liquid gallium.

Two-dimensional measurements of thin film erosion and deposition by colorimetry of interference colors and its application in fusion devices

The paper describes time resolved observations of the erosion of a thin (≈ 105 nm) and transparent a-B:D film on a roof-like graphite test probe (60 mm × 63 mm) in the scrape-off layer plasma of the tokamak Textor-94. Steady state of the erosion pattern was almost achieved after 22 discharges (121.3 s total exposure time). After each of the pulses the interference color pattern in illuminating light of 3200 K color temperature was observed by means of conventional video technique and the color coordinates R, G, B measured. Since they can be related uniquely to the film thickness contour maps and profiles could be evaluated and erosion rates determined. Net deposition on parts of the surface is also observed. Most of the results can be described by erosion due to the hydrogen flux and the simultaneous deposition of carbon and other impurities from the background plasma. The deposition of impurities onto the a-B:D bulk seems to reduce the erosion rates which prolongs its lifetime. This interpretation is backed by AES and NRA analysis of the boron content and by EPMA.

Dean vortices in curved tube flow: 5. 3‐D MRI and numerical analysis of the velocity field

AbstractThe velocity contour profiles within Dean vortices produced by flowing water in a solid‐walled curved tube are quantitatively measured. Magnetic resonance flow imaging using flow encoding with spin warp imaging is used in two and three dimensions to obtain these velocities. These experimental measurements are then compared with simulations obtained from solutions of the Navier‐Stokes and continuity equations for three axial flow rates. Numerical solutions were obtained with a finite volume method for curved tube Poiseuille flow.

The contribution of lateral mass flow effects to the compensation of unequal diffusion rates in the gold-silver system

The mass-flows occurring perpendicular to diffusion direction are discussed as a contribution to the compensation for excess-atom and vacancy flows caused by unequal diffusion rates in gold-silver couples. The lateral mass-flow rates have been derived from surface contour profiles that develop during interdiffusion. The excess-atom and vacancy flows have been determined by an evaluation of concentration penetration curves based on known thermodynamic and diffusion data. The measurements reveal that the relative contribution of lateral mass-flows to the compensation process increases with temperature and annealing time. Usually the contribution is in the percentage range but may become appreciable for smaller diameter diffusion couples.

The antigenic index: a novel algorithm for predicting antigenic determinants

In this paper, we introduce a computer algorithm which can be used to predict the topological features of a protein directly from its primary amino acid sequence. The computer program generates values for surface accessibility parameters and combines these values with those obtained for regional backbone flexibility and predicted secondary structure. The output of this algorithm, the antigenic index, is used to create a linear surface contour profile of the protein. Because most, if not all, antigenic sites are located within surface exposed regions of a protein, the program offers a reliable means of predicting potential antigenic determinants. We have tested the ability of this program to generate accurate surface contour profiles and predict antigenic sites from the linear amino acid sequences of well-characterized proteins and found a strong correlation between the predictions of the antigenic index and known structural and biological data.

A new method for rapid and sensitive detection of bromodeoxyuridine in DNA-replicating cells

A new flow cytometric technique, involving differential fluorescence analysis of two DNA-binding fluorochromes, was used to quantify cellular incorporation of the base analog, bromodeoxyuridine (BrdU), into DNA over short time periods. During analysis of stained cells, the blue fluorescence signal of Hoechst 33342, which is quenched by BrdU-substituted DNA, was subtracted, on a cell by cell basis, from the green-yellow fluorescence signal of mithramycin, which remained stoichiometric to cellular DNA content. Bivariate contour profiles obtained for CHO cells pulse-labeled for 30 min showed that fluorescence quenching of Hoechst 33342 in BrdU-labeled, S phase cells produced fluorescence difference signals that were significantly greater than the difference signals from G 1 and G 2 + M phase cells. Analysis of L1210 cells demonstrated that the amount of BrdU detected was proportional to the length of the labeling period. The novel technique is simple, rapid, and mild; it produces minimal cell loss and does not significantly affect cellular moieties such as DNA, chromatin, or RNA.

Laminin and fibronectin distribution in normal and pathological human muscle

The availability of antisera against collagen and non-collagen proteins of the extracellular matrix has opened new possibilities of studying fibrous infiltration in muscular diseases. We have examined muscle biopsies from 5 controls and 27 patients with various neuromuscular diseases by immunofluorescence and peroxidase—anti-peroxidase. We investigated the distribution of fibronectin and of laminin, a protein present in basement membranes. In normal muscle both were present around blood vessels, axons, muscle spindles and muscle fibres. In addition fibronectin filled the endomysial and perimysial space, the endoneurium and the space between the intrafusal fibres. In pathological muscle laminin distribution was similar to that in normal muscle, but some atrophic fibres appeared to have a thickened contour and irregular profiles were occasionally observed in the absence of histologically demonstrable muscle fibres. Fibronectin was increased in all the conditions with thickened endomysium and perimysium, without displaying any disease-specific character. Findings are compared with the few published observations on fibronectin and collagen types.

The structure of bright-rimmed molecular clouds

view Abstract Citations (36) References (53) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The structure of bright-rimmed molecular clouds. Wootten, A. ; Sargent, A. ; Knapp, G. ; Huggins, P. J. Abstract High spatial resolution, 30 arcsec observations of bright-rimmed molecular clouds in the J = 2-1 and J = 1-0 lines of (C-12)O and (C-13)O are presented, and their physical and kinematical properties are examined. The clouds are individually discussed, showing contour maps and profiles. The physical properties of the rims, their spatial extent, velocity, density, and temperature structure, and the variation of molecular abundances across them are considered. In general, the gas densities increase close to the rims, but temperature enhancements occur over comparatively extended regions. Near the rims the gas kinematics is varied: velocity gradients are observed in several regions, and in IC 1396 line broadening is distinguishable. There is a definite decline in CO abundance near the well-resolved rim in NGC 1977. In none of the clouds does interaction with the adjacent H II region appear to have substantially affected the course of star formation. Publication: The Astrophysical Journal Pub Date: June 1983 DOI: 10.1086/161026 Bibcode: 1983ApJ...269..147W Keywords: Astronomical Spectroscopy; Carbon Monoxide; Interstellar Matter; Line Spectra; Molecular Clouds; Abundance; Gas Density; Gas Dynamics; Gas Temperature; H Ii Regions; High Resolution; Spatial Resolution; Spectral Resolution; Stellar Evolution; Astrophysics full text sources ADS | data products SIMBAD (10)

The functional topography of the sacroiliac joint.

This work analyzes the motion permitted by the topography of the sacroiliac joint surface. Gross contour profiles of the joint were recorded in the frontal and sagittal planes. Best-fit axes of rotation for each contour profile were obtained by statistical methods and were compared with those reported in the literature. There was considerable scatter of the locations of the most likely centers, or axes, of rotation in the frontal and sagittal planes. Were motion to occur about these axes, the articular surfaces would first separate by a distance sufficient to allow them to move over one another. Energy would be needed to separate the joint surfaces being pulled together by the surrounding ligaments. Thus, the sacroiliac joint may function as a shock- absorbing structure by virtue of energy absorbed in the ligamentous tissue.

Static and kinematic parameters of magnetic bubble walls having a horizontal Bloch line pair

The micromagnetic model previously reported has been applied to a selection of materials and to an additional wall type. The stability of unichiral (S=1) walls and walls containing a single horizontal Bloch line pair (HBLP) has been studied numerically for Q in the range 1.4 to 4.6, and for material lengths, normalized to film thickness, between 0.05775 and 0.462. Wall structure, in the form of contour maps and profiles of azimuthal angle, have been obtained for walls without and with a 2π twist (HBLP) centered on the film midplane. The dependence of structural quantities on material parameters is also presented. Bubble mobility dependence on quasi-static wall structure was investigated from the point of view of the gyrovector force density concept. The dependence of the peak magnitude of the gyrovector on material length is discussed, and a relief map of the gyrovector magnitude for a wall containing an HBLP is presented.

Ground-State Energy Eigenvalues and Eigenfunctions for an Electron in an Electric-Dipole Field

Ground-state energy eigenvalues and eigenfunctions are obtained by a variational method for an electron in the field of a finite, stationary, permanent electric dipole. The dipole moments studied cover the range from the minimum value required for binding (${D}_{min}=0.6393 e{a}_{0}$) to $D=400 e{a}_{0}$, where the system is equivalent to the hydrogen atom perturbed slightly by a distant stationary negative charge. The eigenvalues obtained agree with those reported by Wallis, Herman, and Milnes, who determined them by another method in the range $D=0.84e{a}_{0} \mathrm{to} 30e{a}_{0}$. The normalized eigenfunctions display the manner in which the electronic charge density changes from that of the hydrogen atom at very large $D$ to a flat distribution approaching that which is characteristic of a zero-energy continuum state as the minimum moment is approached from above. Optimized variational wave functions for different values of $D$ are presented for use in other calculations. Contour maps and profiles of electronic charge density are shown for a number of values of $D$. Mean values of the powers -1, 1, and 2 of the distances of the electron from the dipole charges are also calculated.

GEOLOGY OF AN AREA OF THE CARLSBERG RIDGE, INDIAN OCEAN

An area of the crest of the Carlsberg Ridge, the mid-ocean ridge in the northwestern Indian Ocean, has been surveyed in detail; the area measures 50 by 38 nautical miles. Contour maps and profiles show the results obtained with a precision echo-sounder and a proton magnetometer. Within the surveyed area, a dextral tear fault displaces the median magnetic anomaly and the median valley through about ten miles. Fresh basalt lavas have been dredged from the area together with metamorphosed basaltic rocks. Brecciation and hydrothermal alteration of the crustal rocks in a comparatively wide fault zone may explain why the pattern of magnetic anomalies seems to have been expunged along the fault.

Structural studies in the pre-Cambrian of western Greenland. Part II. Geology of Tovqussap nunâ

Structural studies in the pre-Cambrian of western Greenland. Part II. Geology of Tovqussap nunâ