bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rotational band identification: A model‐based detection and estimation approach
Authors: Candy J. V. , Manatt D. R. , Barnes F. L. , Becker J. A. , Henry E. A. , Brinkman M. J. 
Published: March 2007

AbstractNuclear theory predicts that secondary minima develop in the nuclear potential energy surface of some nuclei as they are stretched or elongated. Some minima are deep enough to support quasistationary states. The states are metastable because the decay is inhibited by the required shape change. Detection of these metastable states and their associated rotational bands allows us to investigate nuclei at large deformations and test existing theoretical predictions. The identification of these difficult‐to‐locate structures will permit the detailed study of nuclei at extraordinarily high deformation, providing new insights into nuclear structure. We discuss the application of model‐based image processing techniques to detect and enhance the nuclear rotational bands in noisy experimental measurements. The aim of the experiment is to identify the shape isomer by detecting the presence of the associated rotational band pattern. Unfortunately, the band signal is only ≈︁1% or less of the amplitude of similar disturbance signals due to the nuclear states of normal deformation; thus the signal‐to‐noise ratio is quite poor. Thus it is necessary to investigate image processing techniques to detect and extract the predicted band pattern. Using a model‐based approach, that is, characterizing a particular band by a simple mathematical model and incorporating it into an image processing scheme, we show that we are able to solve the band pattern detection and enhancement problems from both synthesized and measured experimental data.
Planar‐surface matching approach for estimating target location using laser range imagery
Authors: Li Robert Y. 
Published: March 2007

AbstractA laser radar sensor provides 3D information about a scene by using range measurements. A Hough transform approach is used to extract geometric information from these range values in order to identify planar building walls. Features of the extracted walls, such as their size, orientation, and distance relative to other walls, can be used to match against a reference list of walls with this spatial information. Target location can then be estimated by solving simultaneous equations using matched planar surfaces. Experimental results of computed target locations are shown to be satisfactory.
Nonlinear prediction based on a two‐level markovian image model and a comparison analysis
Authors: Bezruk Andrei 
Published: March 2007

AbstractIn this article a nonlinear method of image prediction is considered. This problem arises in image coding. The method is based on a two‐level statistical image model. The first level corresponds to statistical model of the contour image, and the second level corresponds to a model of brightness given the contour image. An adaptive method of image prediction is considered. Computer simulation is performed in order to compare the results of prediction in cases of linear and nonlinear predictors with both previous and surrounding pixels. Comparison is made in terms of prediction gain.
Width‐independent fast skeletonization algorithm for binary pictures
Authors: Kiyko V. M. , Schlesinger M. I. 
Published: March 2007

AbstractAn effective algorithm of skeletonization for digital binary pictures based on input‐time‐tracing principle and sequential decomposition of input picture into simple parts is described. The proposed algorithm is fast and requires no image memory. Its computing complexity does not depend on the thickness of picture patterns and is determined not by the number of picture pixels but by the essentially small number of horizontal and vertical lines constituting the contour of the picture.
Two‐dimensional operation of a scanning optical microscope using a vibrating knife‐edge corner
Authors: Korpel A. , Samson S. , Feldbush K. 
Published: March 2007

AbstractWe analyze and demonstrate a scanning optical microscope that uses a vibrating knife‐edge corner to provide arbitrary, electronically variable resolution. Implications for general near‐field microscopy are discussed.©1993 John Wiley & Sons Inc
Imaging device that uses the wavelet transformation as the image reconstruction algorithm. II. The L transform
Authors: Letcher John H. 
Published: March 2007

AbstractAn ultrasound‐device image‐reconstruction algorithm has been described previously that uses orthonomal wavelets as the basis of a transform space. The transform algorithms make it possible to analyze the reflected ultrasound signal from a sample to produce a map of one of its internal properties, the acoustical impedance. Conventional wavelets do not exhibit translation invariance, the lack of which ofttimes generates nonzero expansion coefficients for wavelets of lower sequency than the transmitted signal. By a transformation of basis to a set of functions which exhibit a form of translation invariance the aforementioned problem is removed. However, the new functions are no longer orthogonal. An algorithm is described to perform this transformation extremely efficiently. Also described is an algorithm to unsmear the image due to the fact that the transmitted signal may not be a single wavelet but instead is a short sequence (linear combination) of wavelets. The coefficients of the array used to deconvolve the signal are determined by performing a forward wavelet transformation on the transmitted signal itself.©1994 John Wiley & Sons Inc
Tomographic imaging of 3D seismic low‐velocity anomalies to simulate monitoring of enhanced oil recovery
Authors: Brzostowski Matthew A. , McMechan George A. 
Published: March 2007

AbstractTomographic velocity estimation of a three‐dimensional (3D) anomaly as a function of time is implemented by the simultaneous iterative reconstruction technique (SIRT) using synthetic observed travel times as data. Rays are retraced every 6–7 iterations to ansure consistency between rays and velocities. An expanding steam front modeled within a shallow reservoir is imaged at two points in time using three different survey geometries containing both cross‐well and well‐to‐surface paths. Synthetic data can be used to evaluate and optimize survey design and resolution prior to field data acquisition. Resolution is evaluated by computing point spread functions and can (theoretically) be made as high as desired (up to the limit imposed by wave phenomena and the noise in the data) by increasing the number of independent observations and correspondingly reducing the image voxel size. ©1994 John Wiley & Sons Inc.
Analysis of MTF degradation in the imaging of cells in a flow system
Authors: Ong S. H. , Nickolls P. M. 
Published: March 2007

AbstractThe time‐delay and integration method can be used with a charge‐coupled device array to acquire images of cell in a flow cytometer. The loss of high spatial frequency components in images acquired with this technique is studied by deriving the modulation transfer function (MTF) for each of the main causes of image degradation: finite sampling aperture, nonsynchronism between image movement and charge transfer rate, discrete charge motion, transfer inefficiency, and axis misalignment. The system MTF and resolution in the horizontal and vertical directions are then examined.©1994 John Wiley & Sons Inc
Video compression for the grand alliance: A historical perspective
Authors: Lebègue Xavier , McLaren David , Saint‐Girons Régis 
Published: March 2007

AbstractThis article outlines the evolution of the Grand Alliance (GA) highdefinition television (HDTV) standard from its divided beginnings among several systems to its final state as the proposed standard for HDTV transmission in the United Stales today. Earlier video compression standards are briefly described, and their influence on the first four all‐digital HDTV proposals is demonstrated. The salient features of each proposed video compression system are high‐lighted, and the more recent MPEG‐2 compression standard is introduced. MPEG‐2 was adopted as the basis for video compression by the GA, a group of the former HDTV competitiors. The formation of the GA is described, and the work of its Video Compression Specialists Group on evaluating modifications to MPEG‐2 is reviewed.©1994 John Wiley & Sons Inc
Partial closed‐loop versus open‐loop motion estimation for HDTV compression
Authors: McVeigh Jeffrey S. , Wu Siu Wai 
Published: March 2007

AbstractMotion estimation is a vital function of video coders that use motion compensated prediction to exploit the temporal redundancy of video signals. The reference images used in the motion estimation process can be either original images (open‐loop architecture) or reconstructed images (closed‐loop architecture). While the closed‐loop architecture is intuitively superior to the open‐loop architecture, closed‐loop motion estimation is more difficult to implement in a real‐time video encoder. A compromise is to perform open‐loop integer‐pel accurate motion estimation followed by closed‐loop half‐pel accurate estimation. In this article we present a comparative study of the performance of half‐pel closed‐loop versus open‐loop motion estimation for coding of high definition television with the MPEG algorithm. Simulation results indicate that on average, closed‐loop half‐pel accurate motion estimation provides slightly better performance than open‐loop half‐pel accurate estimation. This improvement depends on the bit rate of the coded video biststream. For relatively high bit rates, the closed‐loop implementation often provides no improvement, and sometimes an actual degradation of performance. An analysis of why a closed‐loop implementation does not guarantee a better performance is presented.©1994 John Wiley & Sons Inc
The IBM POWER visualization system: A system for HDTV postproduction, and more
Authors: Epstein David A. , McDowell Curtis S. 
Published: March 2007

AbstractThe unique combination of processing power, memory capacity, and I/O bandwidth found in the IBM POWER Visualization System (PVS) makes it an ideal tool for high‐end, format and resolution‐independent, digital postproduction applications. From computer graphics rendering to video editing, rotoscoping, and special effects, the versatile nature of this general‐purpose computer allows it to adapt constantly to the specific tasks required during almost any phase of the postproduction process. In this articles, we first examine the hardware architecture of the PVS with specific attention paid to the different subsystems and peripherals which provide the large computational power and bandwidth necessary to do HDTV editing and effects work. Next, we describe the PVS system software layer which enables application level software to fully use all of the capabilities of the hardware. We then explore a novel on‐line, nonlinear editing and effects environment available for the PVS, which allows HDTV resolution material to be digitally edited and processed at full resolution. Finally, we conclude by describing some of the applications of the PVS which allow it to be used in a variety of other ways.©1994 John Wiley & Sons Inc
Development of treatment techniques for radiotherapy optimization
Authors: Lind Bengt , Brahme Anders 
Published: March 2007

AbstractOver the last decade a large number of new treatment techniques have been developed to allow a true optimization of the delivered dose distribution in radiation therapy. The most important clinical requirement of most optimization techniques is to be able to deliver strongly nonuniform beams on the patient from arbitrary directions. For very complex tumors the number of beams required to eradicate the tumor without severe injury to normal tissues is quite high, to accurately make the three dimensional dose distribution conform to the target volume. For more simple target geometries fewer beams are sufficient, and in many cases with small tumors the classical uniform rectangular beams will do nicely. A number of new treatment techniques, from narrow beam robot mounted linear accelerators through fan beam devices using linear multileaf collimation in rotary gantries, to the most flexible external beam devices with scanned electron and photon beams and/or dynamic multileaf collimation available over the whole treatment field, are now rapidly coming into clinical use.
Functional spectroscopy of brain activation following a single light pulse: Examinations of the mechanism of the fast initial response
Authors: Hennig J. , Janz C. , Speck O. , Ernst T. 
Published: March 2007

AbstractLocalized proton spectroscopy using the PRESS sequence was performed to measure the free induction decay of the water signal in a 2 × 2 × 2 = ml voxel located in the visual cortex after a short light pulse. The experiment was run continuously with a repetition time of 400 ms; the onset of the light pulse was triggered by the spectrometer. The FIDs were measured as a function of the echo time (TE) and the length of the stimulus (TS). The time course showed three different phases: An initial response was observed 400 ms after the onset of the stimulus, which was demonstrated to be mainly a change in the apparent spin density and/or T1 with a minor contribution of T2*. No significant change in T2 could be measured. Changes in the ionic cell environment and/or the subsequent increase in cell size upon stimulation are discussed as a potential mechanism for the observed signal response.
Evaluating conventional FMRI with respect to noninvasive localization of neuronal activity
Authors: Beisteiner R. , Erdler M. , Teichtmeister C. , Moser E. , Deecke L. 
Published: March 2007

AbstractConventional functional magnetic resonance imaging (FMRI) allows the measurement of functional cerebral blood flow changes occurring with specific tasks using standard clinical MR systems. However, the spatial relationship between neuronal activity and functional cerebral blood flow changes is not yet known. This article reviews studies which compared the center of neuronal activation (measured by magnetoencephalography) with that of the hemodynamic response (measured by FMRI) using motor and visual stimulation.
Super‐resolution of images: Algorithms, principles, performance
Authors: Hunt B. R. 
Published: March 2007

AbstractA new facet of image restoration research has begun to emerge in recent years: super‐resolution of images, which we define as the processing of an image so as to recover object information from beyond the spatial frequency bandwidth of the optical system that formed the image. Simple Fourier analysis would indicate that super‐resolution is not possible. Therefore, it is important to reconcile this simplistic view with the existing algorithms that have been demonstrated to achieve super‐resolution. In this article, we consider some of the algorithms that have demonstrated super‐resolution and discuss the common principles that they share which makes it possible for them to recover some of the lost bandwidth of the object. We also consider the question of super‐resolution performance, which is the measure of how much lost bandwidth can be recovered from a super‐resolution algorithm, and how the performance is related to the algorithm principles that allow super‐resolution to occur. We conclude with examples of super‐resolution.
Multiresolution in astronomical image processing: A general framework
Authors: Murtagh Fionn , Starck Jean‐Luc , Bijaoui Albert 
Published: March 2007

AbstractMultiresolution transforms, including a wavelet transform, are applied simage visualization, image restoration, filtering and compression, × object detection. Variance stabilization is used, when appropriate, cater for common astronomical image noise models. We discuss idation of such methods in the case of astronomical image processing. A range of examples illustrate the effectiveness of this aproach in handling point source and extended astronomical objects.
Convolution connection paradigm neural network enables linear system theory‐based image enhancement
Authors: Blass William E. , Mahan Stephen L. , Chin Gordon 
Published: March 2007

AbstractA new type of robust numeric solution of one form of the Fredholm integral equations of the first king has been discovered. This discovery has its most immediate and important applications in the deconvolution or deblurring of data acquired using scientific instruments. A solution of this integral equation has very general applications. For example, investigator‐controlled mapping of the instrumental point‐spread function to a more useful form is made feasible. The solution of the linear systems imaging model integral equation results from operations performed on the instrumental kernel, response, or point‐spread function with the direct result being the production of a robust, effective inverse kernel. The effective inverse is robust even in the presence of noise. The generation of the inverse kernel in no way depends on the observational data. Therefore, the image enhancement produced by this method contrasts with other numeric schemes that operate only on the observed data. This is an important distinction. This technique, which uses simple numeric operations, offers the possibility of attaining real‐time data enhancements for observational instruments. The concept of taking control of the instrument kernel or point‐spread function forms the basis of the work presented. Investigations of the application of artificial neural networks to resolution enhancement of Hubble Space Telescope imagery have led to a novel extended instrument paradigm that permits reliable and robust resolution enhancement. In addition to resolution enhancement, the fruits of this investigation have provided a powerful data mapping tool that permits nontrivial, numeric apodization of observed data. The applications of the novel convolution connection paradigm neural network has a great potential for multidisciplinary applications such as resolution enhancement of image and spectral data.
A tale of two proteins: Differential roles and regulation of Smad2 and Smad3 in TGF‐β signaling
Authors: Brown Kimberly A. , Pietenpol Jennifer A. , Moses Harold L. 
Published: March 2007

AbstractTransforming growth factor‐beta (TGF‐β) is an important growth inhibitor of epithelial cells, and insensitivity to this cytokine results in uncontrolled cell proliferation and can contribute to tumorigenesis. Smad2 and Smad3 are direct mediators of TGF‐β signaling, however little is known about the selective activation of Smad2 versus Smad3. The Smad2 and Smad3 knockout mouse phenotypes and studies comparing Smad2 and Smad3 activation of TGF‐β target genes, suggest that Smad2 and Smad3 have distinct roles in TGF‐β signaling. The observation that TGF‐β inhibits proliferation of Smad3‐null mammary gland epithelial cells, whereas Smad3 deficient fibroblasts are only partially growth inhibited, suggests that Smad3 has a different role in epithelial cells and fibroblasts. Herein, the current understanding of Smad2 and Smad3‐mediated TGF‐β signaling and their relative roles are discussed, in addition to potential mechanisms for the selective activation of Smad2 versus Smad3. Since alterations in the TGF‐β signaling pathway play an important role in promoting tumorigenesis and cancer progression, methods for therapeutic targeting of the TGF‐β signaling pathway are being pursued. Determining how Smad2 or Smad3 differentially regulate the TGF‐β response may translate into developing more effective strategies for cancer therapy. J. Cell. Biochem. 101: 9–33, 2007. © 2007 Wiley‐Liss, Inc.
Change in a protein's electronic structure induced by an explicit solvent: An ab initio fragment molecular orbital study of ubiquitin
Authors: Komeiji Yuto , Ishida Toyokazu , Fedorov Dmitri G. , Kitaura Kazuo 
Published: March 2007

AbstractThe effect of solvation on the electronic structure of the ubiqutin protein was analyzed using the ab initio fragment molecular orbital (FMO) method. FMO calculations were performed for the protein in vacuo, and the protein was immersed in an explicit solvent shell as thick as 12 Å at the HF or MP2 level by using the 6‐31G* basis set. The protein's physical properties examined were the net charge, the dipole moment, the internal energy, and the solvent interaction energy. Comparison of the computational results revealed the following changes in the protein upon solvation. First, the positively charged amino acid residues on the protein surface drew electrons from the solvent, while the negatively charged ones transfer electrons to the solvent. Second, the dipole moment of the protein was enhanced as a result of the polarization. Third, the internal energy of the protein was destabilized, but the destabilization was more than compensated for by the generation of a favorable protein–solvent interaction. Finally, the energetic changes were elicited both by the electron correlation effect of the first solvent shell and by the electrostatic effect of more distant solvent molecules. These findings were consistent with the picture of the solvated protein being a polarizable molecule dissolved in a dielectric media. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2007
C‐Reactive protein: Current status and future perspectives
Authors: Hokama Yoshitsugi , Nakamura Robert M. 
Published: March 2007

AbstractThis review encompasses all aspects of recent C‐Reactive protein studies. Emphasis has been in the areas of (1) the physical, chemical, and potential functions of C‐Reactive protein; and (2) the pass and recent procedures of C‐Reactive protein analysis relative to simplicity and sensitivity. The responses of C‐Reactive protein in various diseases and its future prospects are also discussed in this review.
Detection of oncogene‐related proteins with site‐directed monoclonal antibody probes
Authors: Niman Henry L. 
Published: March 2007

AbstractSequences of oncogenes define related families and provide a large data bank for the production of synthetic peptides. These peptides can be used to produce site‐directed monoclonal antibody probes, which identify oncogene‐encoded and oncogene‐related proteins. The creation and utilization of these probes for clinical laboratory analysis are discussed.
Chediak‐higashi syndrome derived t cell lines manifest giant lysosomal granules, normal natural killer cell, and lectin‐mediated cytotoxicity
Authors: Merino Fernando , Collins Michaeleen , Purtilo David T. 
Published: March 2007

AbstractLymphoblastoid T cell lines from patients with Chediak‐Higashi syndrome (CHS) have been established by stimulating lymphocytes with phytohemagglutinin and interleukin‐2. This culture technique produced T cells containing giant granules which are characteristically seen in peripheral blood leukocytes of children with the disease. The granules were lysosomes as demonstrated by their reactivity with acid phosphatase. Functionally, they exhibited normal natural killer cell activity and/or lectin‐induced cytotoxicity. Variations in function of freshly obtained and long‐term cultured T cells are discussed. These cell lines will permit further studies to elucidate defects in lymphoid cells derived from patients with CHS.
Generation and measurement of interleukin‐1, interleukin‐2, and mitogen levels in small volumes of whole blood
Authors: Lyte Mark 
Published: March 2007

AbstractWhole blood assays that allow simultaneous performance of IL‐1 and IL‐2 production as well as lymphocyte mitogen responsiveness are described. The advantages to these techniques are: (1) small volume of sample required (1 ml of whole blood or less), (2) time required to perform the assays (10 min), and (3) use of whole blood rather than isolated cells in the evaluation of immune competency which is more reflective of the in vivo condition. The techniques described lend themselves to application in the clinical setting.