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At least 487 records · Page 27Linked to original sources
PubMedDate not supplied

Convolution and correlation: a case study of scanning imaging and analysis systems.

The relationship between convolution/correlation operation and the data acquisition process of the scanning microscope and spectrometer families is analyzed. It is shown that a coordinate or event sensitive detector, and the intrinsic or extrinsic property of the specimen response, are two important factors in distinguishing the data acquisition mode of such systems. Four types of convolution- and correlation-based modes are extracted to illuminate the physical characteristics of scanning imaging and analysis systems by focusing on the probe, specimen, detector, and their relationships. Criteria for identifying these modes are explored. In addition, the physical meanings of general existing coefficients between the independent variables of convolution and correlation are investigated.

Journal Article↗
PubMedDate not supplied

COSAS 2.0--a Macintosh-based stereological analysis system.

Quantitation of morphological data is a component of both basic and clinical research. Often it is necessary to extract three-dimensional information from two-dimensional images. Stereological analysis, the most reliable means of achieving this, is also increasingly used as a diagnostic tool in pathology. COSAS, a COmputerized Stereological Analysis System, is software which allows rapid recording of morphological data from two-dimensional images and performance of analyses necessary for both quantitation and three-dimensional interpretation. COSAS is reliable and easy to use. It was previously available in a VAX-based version (Cornacchia and Black, 1988). An improved version, COSAS 2.0, is now available for use on the Macintosh. COSAS 2.0 is considerably more "user friendly" and flexible than the VAX version of the program. COSAS 2.0 eliminates the necessity for the user to be linked with a large computer. COSAS 2.0 has the ability to interface with other commercially available software for scanned images (e.g., Adobe Photoshop, NIH-Image) and data manipulation (e.g., EXCEL, Delta Graphics). These features make it useful to both research and clinical laboratories. Although designed for the biologist, the system may be used to study cross sections of any solid. It could be of interest to material scientists, petrographers, and ceramicists, all of whom need to obtain quantitative information about three-dimensional spatial organization from two-dimensional sections or projections.

Animals↗
PubMed1992

Systems analysis of the tricarboxylic acid cycle in Dictyostelium discoideum. I. The basis for model construction.

A steady-state model of the tricarboxylic acid cycle was constructed using a dynamic systems analysis computer program, METASIM. The model was based on radioactive tracer analyses which provided flux relationships and compartmented metabolite concentrations. Ten of the enzymes modeled were purified and characterized from Dictyostelium discoideum. Although experimentally determined enzyme mechanisms and constants were used in the model, Vmax values were found to be unreliable, i.e. they did not reflect enzyme activity in vivo. This value was therefore calculated as the only unknown in each enzyme kinetic equation and called Vvivo, to distinguish it from Vmax determined in vitro.

Animals↗
PubMed2004

Micro total analysis system (micro-TAS) in biotechnology.

Nanobiotechnology raises fascinating possibilities for new analytical assays in various fields such as bioelectronic assembly, biomechanics and sampling techniques, as well as in chips or micromachined devices. Recently, nanotechnology has greatly impacted biotechnological research with its potential applications in smart devices that can operate at the level of molecular manipulation. Micro total analysis system (micro-TAS) offers the potential for highly efficient, simultaneous analysis of a large number of biologically important molecules in genomic, proteomic and metabolic studies. This review aims to describe the present state-of-the-art of microsystems for use in biotechnological research, medicine and diagnostics.

Biosensing Techniques↗
PubMed2005

Intact-protein-based high-resolution three-dimensional quantitative analysis system for proteome profiling of biological fluids.

The substantial complexity and vast dynamic range of protein abundance in biological fluids, notably serum and plasma, present a formidable challenge for comprehensive protein analysis. Integration of multiple technologies is required to achieve high-resolution and high-sensitivity proteomics analysis of biological fluids. We have implemented an orthogonal three-dimensional intact-protein analysis system (IPAS), coupled with protein tagging and immunodepletion of abundant proteins, to quantitatively profile the human plasma proteome. Following immunodepletion, plasma proteins in each of paired samples are concentrated and labeled with a different Cy dye, before mixing. Proteins are subsequently separated in three dimensions according to their charge, hydrophobicity, and molecular mass. Differences in the abundance of resolved proteins are determined based on Cy dye ratios. We have applied this strategy to profile the plasma proteome for changes that occur with acute graft-versus-host disease (GVHD), following allogeneic bone marrow transplantation (BMT). Using capillary HPLC ESI Q-TOF MS, we identified 75 proteins in the micromolar to femtomolar range that exhibited quantitative differences between the pre- and post-GVHD samples. These proteins included serum amyloid A, apolipoproteins A-I/A-IV, and complement C3 that are well-known acute-phase reactants likely reflecting the post-BMT inflammatory state. In addition, we identified some potentially interesting immunologically relevant molecules including vitamin D-binding protein, fetuin, vitronectin, proline-rich protein 3 and 4, integrin-alpha, and leukocyte antigen CD97. IPAS provides a combination of comprehensive profiling and quantitative analysis, with a substantial dynamic range, for disease-related applications.

Adult↗
PubMed1985

System analysis and nucleic acid sequence banks.

The mass of published nucleic acid sequence data has required the design of several computerized data bases. We show that this activity is related to the methodology of System Analysis and that data bases are a means of modeling biological knowledge. As an example, the ACNUC data base we have created is presented.

Base Sequence↗
PubMed1992

In vivo observation of the axial movement of intraocular lenses through an anterior eye segment analysis system.

The small axial movement of the anterior surface of implanted intraocular lenses (IOLs) were examined in pseudophakic eyes with one-piece and three-piece IOLs using an anterior eye segment analysis system. The movement was calculated as the distance between the posterior surface of the cornea and the anterior surface of an IOL under a normal pupil size, following the instillation of 1% pilocarpine and 1% cyclopentolate solutions, respectively. The axial movement including movement after instillation of pilocarpine and cyclopentolate was 0.17 +/- 0.06, 0.05 +/- 0.07 and 0.13 +/- 0.06 mm, in phakic eyes and eyes with one-piece and three-piece IOLs, respectively. Image analysis techniques using Scheimpflug images proved its usefulness in the research field of IOL implantation.

Adolescent↗
PubMed2001

Chronic bilateral pallidal stimulation and levodopa do not improve gait in the same way in Parkinson's disease: a study using a video motion analysis system.

Chronic bilateral internal globus pallidus (GPi) stimulation allows control of levodopa induced dyskinesias (LID) and motor symptoms in severe Parkinson's disease (PD). The effect on gait has not been clearly established. Different results have been reported, mostly consisting of clinical data. The aim of this study was to evaluate, by means of a video motion analysis system (optoelectronic VICON system), the influence of bilateral GPi stimulation on gait in PD. Five patients underwent bilateral GPi stimulation. The preoperative and postoperative (3 months after surgery) clinical gait disturbances (items 29 and 30 of the motor UPDRS), as well as spatial and temporal gait measurements (namely cadence, velocity, stride and step times, single and double limb support times, stride and step lengths) were analysed in off condition (the patient had received no treatment for 12 hours or merely the lowest dose of levodopa allowing him to walk for the gait analysis) and in the on drug condition (after administration of 200 mg of levodopa). The gait analysis was performed with the VICON system. In off condition, there was a statistically significant improvement after surgery for UPDRS III and gait (clinically assessed). In on drug condition, there was a significant improvement for LID whereas UPDRS III and clinical assessment of gait were unchanged. The VICON system also showed that surgery improved gait especially in off condition, but also in on drug condition. Our method allowed exact quantification of the influence of surgery on gait characteristics. As compared with levodopa treatment, the effect of stimulation seems to be different. Indeed, the results suggest only limited effects of pallidal stimulation on the control of stride length and rather point to compensatory additional mechanisms.

Aged↗
PubMed2006

[A specific therapy for chronic depression. McCullough's Cognitive Behavioral Analysis System of Psychotherapy].

Chronic depression is a common disorder which causes significant impairment and enormous treatment costs. Traditional pharmacological and psychological treatment approaches have shown only modest success. The Cognitive Behavioral Analysis System of Psychotherapy (CBASP) by James McCullough is the only therapy developed specifically for chronic depression. It integrates behavioral, cognitive, and interpersonal strategies. The approach is supported empirically and shown to be effective. This article presents the state of the art regarding research in psychotherapeutic treatment for chronic depression. In addition, the development of the approach and therapeutic strategies and techniques of CBASP are described.

Antidepressive Agents↗
PubMed1988

Improved algorithms for automatic bone histomorphometry on a numerized image analysis system.

Quantitative histological methods have proved to be the most effective methods in bone disease research. Faster and more accurate techniques are currently needed. We have developed a simple digitized image analysis system which allows accurate measurements of trabecular bone mass. The algorithm is based on the 'four-connected sets' mathematical theory. Given a numerized image displayed by a CCD camera, the algorithm recognizes all possible four-connected sets and provides area measurements. The first procedure automatically eliminates small, irrelevant profiles (wrinkles, cell nuclei, etc.) while larger profiles are erased interactively. The second procedure similarly erases the artefactual defects within the trabeculae (artefactual cracks or empty osteocytic lacunae). The method was shown to be very accurate and time-saving.

Algorithms↗
PubMed2005

[Development of three-dimensional kinematic analysis system for artificial knee implants using X-ray fluoroscopic imaging].

To achieve quantitative assessment of 3D dynamic motion of artificial knee implants under clinical conditions, we developed a 3D kinematic analysis system using X-ray fluoroscopic imaging. The 3D pose-estimation technique for knee implants was built on a 2D/3D registration algorithm, which determines the spatial pose for each femoral and tibial component from the knee implant contours and computer-assisted design (CAD) models of the implant. In order to validate the accuracy of the 3D pose estimation and the system, computer simulation and in vitro tests were performed using images of knee implants taken in 10 different poses with respect to X-ray focus. Computer simulation tests showed that the root mean square errors (RMSE) for all variables were less than 1.0 mm 1.0 degrees. In vitro tests showed that the RMSE for translation perpendicular to the X-ray image plane was about 1.5 mm, while the accuracy of the remaining two translational and three rotational variables was found to be sufficient for analyzing knee kinematics. Computation time in 3D pose estimation was then obtained in less than 30 seconds for each frame. In clinical application, dynamic movement in deep knee bending was quantitatively analyzed, and the feasibility and effectiveness of the system was demonstrated.

Algorithms↗
PubMed1991

Linear systems analysis of the relationship between firing of deep cerebellar neurons and the classically conditioned nictitating membrane response in rabbits.

The correlation of the activity of neurons in the interposed and dentate nuclei of the cerebellum with conditioned movements of the nictitating membrane was investigated using linear systems analysis. The activity of single deep cerebellar nuclear cells was assumed to be the input to a linear system that produced nictitating membrane movement. Data were initially analyzed with a causal model to assess the degree to which past neural activity predicted the conditioned response. 55 of 165 cells had correlation coefficients of 0.50 or greater between the model's moment-to-moment output and the actual output, with two interpositus cells having correlation coefficients of greater than 0.90. Double-sided impulse responses indicated that afference from the face and efference copy probably affect deep cerebellar neural activity. Nonlinearities were also found in the relationship between neuronal activity and conditioned movement. It was concluded that cerebellar deep nuclear firing is highly correlated with future nictitating membrane movements but that the firing-movement relationship contains noncausal and nonlinear components.

Animals↗
PubMed2003

System analysis of links interactions and development of ecosystems of different types.

The anthropogenic impact on the Earth's ecosystems are leading to dramatic changes in ecosystem functioning and even to destruction of them. System analysis and the use of heuristic modeling can be an effective means to determine the main biological interactions and key factors that are of high importance for understanding the development of ecosystems. Cycling of limiting substances, induced by the external free energy flux, and trophic links interaction is the basis of the mathematical modeling studies presented in this paper. Mathematical models describe the dynamics of simplified ecosystems having different characteristics: 1) different degrees of biotic turnover closure (from open to completely closed); 2) different numbers of trophic links (including both "top-down", "bottom-up" regulation types); 3) different intensities of input-output flows of the limiting nutrient and its total amount in the system. Adaptive values of the changes of lower hierarchical levels (populational, trophic chain level) are to be estimated by integrity indices for total system functioning (e.g. NPP, total photosynthesis). The approach developed can be used for evaluating the contributions of lower hierarchical levels to the functioning of the higher hierarchical levels of the system. This approach may have value for determining biomanipulation management and their assessment.

Biomass↗
PubMed2002

Intra-observer and inter-observer repeatability of anterior eye segment analysis system (EAS-1000) in anterior chamber configuration.

BACKGROUND: Anterior chamber configuration can be assessed via optical or ultrasonic techniques. Scheimpflug photography is a non-invasive method measuring the anterior segment. The Anterior Eye Segment analysis system, EAS-1000, utilises the Scheimpflug principle and was found to have good repeatability. Previous repeatability studies, however, have had limitations in their design. The current study investigated the intra-observer and interobserver repeatability of the EAS-1000. METHODS: Twenty-five healthy young subjects were recruited. The anterior chamber angles in different quadrants were measured by two examiners for interobserver analysis. The first examiner repeated the measurement at another session for intra-observer analysis. The 95% limits of agreement and intra-class correlation coefficient (ICC) were calculated. The anterior chamber depth was also measured and compared with ultrasound biometry. RESULTS: The anterior chamber angle assessment demonstrated good intra-observer (ICC ranging from 0.77 to 0.90 for different quadrants) and interobserver (ICC ranging from 0.68 to 0.81 for different quadrants) repeatability. The 95% intra-observer limits of agreement were within +/-5 degrees. The 95% interobserver limits of agreement were within +/-6 degrees. There was no significant difference between male and female subjects or among angles at different quadrants. The anterior chamber depth was found to be repeatable (ICC > 0.90) with 95% limits of agreement +/-0.1 mm. The anterior chamber depth was shallower than that obtained from ultrasound biometry. CONCLUSIONS: The EAS-100 is a non-invasive instrument which is repeatable for measuring the anterior chamber angle and depth. It provides quick results and is good for screening purposes. There is an under-estimation of anterior chamber depth, as previously reported.

Adolescent↗
PubMed1983

Computerized nutrient data bases: I. Comparison of nutrient analysis systems.

Food composition tables now being compiled include a wide range of food items and nutrients. This trend is paralleled in the development of computer-stored nutrient data bases that are being utilized for numerous applications, such as cost-optimized menu planning, dietary record analysis, and nutritional assessment. In 1976, several participants at the National Nutrient Data Bank Conference agreed to cooperate in a comparative study to analyze a common one-day dietary record. The results of three subsequent analyses indicated that the values for nutrients varied considerably even after elimination of coding judgments relative to portion size and selection of food items. The results of the study indicated the need for an assessment methodology suitable for evaluating performance of a computerized nutrient analysis system.

Computers↗
PubMed1993

Operational departmentwide picture archiving communication system analysis using discrete event-driven block-oriented network simulation.

The accurate prediction of image throughput is a critical issue in planning for and acquisition of any successful picture archiving and communication system (PACS). Simulation plays an important role in this effort. The PACS image management chain is decomposed into eight subsystems. These subsystems include network transfers over three different networks and five software programs and/or queueing structures. This decomposition is used to create a simulation model that was effectuated using commercially available block-oriented network simulation software. From the PACS database, the traffic generation patterns of the imaging modality devices are used to drive the simulation. The simulation models the image file flow through the PACS for a 24-hour period. The behavior of the simulated traffic generators agreed well with the values derived from the PACS database. The mean delay for the simulated PACS is found to be 225 +/- 59 seconds. The delay time was found to vary during the simulated 24-hour cycle in a consistent manner with observations. This simulation provides estimates on what a radiological department can expect from a PACS in terms of throughput, utilization, and delay. The block-oriented network simulator (BONeS, Comdisco Systems Inc, Foster City, CA) simulation model of the modeled PACS is highly accurate. The models for the imaging modality traffic sources are validated with a high degree of accuracy. The simulation model allows for the study of what happens to the delay time under various loads. In this simulation, the reformatting process was determined to be the bottleneck causing a large increase in delay time under heavy loads.

Computer Communication Networks↗
PubMed1976

Systems analysis of computerized EKG processing center.

A functional description of a computerized system for analysis of electrocardiograms (EKGs) is presented. Although it is recognized that the diagnostic accuracy of the program is the critical parameter in determining system acceptance, other system features such as quality control, turn around time and cost are shown to be of high importance. A digital simulation of alternative configurations for on-line data acquisition is presented. The simulation predicts the system throughout and wait times in different phases of a telephone EKG transmission for combinations of interfaces, telephone lines and acquisition procedures. These results should be helpful in selecting the appropriate configuration for each special situation.

Computers↗
PubMed1993

Quantitation of immunocytochemical estrogen and progesterone receptor content in fine needle aspirates of breast carcinoma using the SAMBA 4000 image analysis system.

Evaluation of estrogen receptors (ER) and progesterone receptors (PR) in breast carcinoma using ER and PR immunocytochemical assays (ER-ICA and PR-ICA) has traditionally been semiquantitative at best. We investigated the use of the SAMBA 4000 image analysis system for quantitation of immunocytochemical ER content in 23 cases and PR content in 20 cases of breast carcinoma after obtaining cytology specimens by fine needle aspiration (FNA). We compared the quantitative assessment obtained by image analysis, the quick score (QS), to the biochemical assay as well as to the ER-ICA and PR-ICA semiquantitative visual histochemical score (H-score). Using Pearson's linear correlation coefficient, we demonstrated that for both ER and PR, the QS obtained by the "area" or "nuclear" programs correlated significantly with the H-scores. However, while the QS obtained on the area program for both ER and PR correlated significantly with the biochemical assay, the QS obtained on the nuclear program did not. The discrepancy might reflect the smaller number of cells evaluated with the nuclear program as compared to the area one. These results show that the SAMBA 4000 system provides an objective means of quantitating ER and PR content by immunocytochemical methods.

Biopsy, Needle↗