Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Systems Analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 397 records · Page 22Linked to original sources
PubMed2003

Decision support for road system analysis and modification on the Tahoe National Forest.

The United States Forest Service is required to analyze road systems on each of the national forests for potential environmental impacts. We have developed a novel and inexpensive way to do this using the Ecosystem Management Decision Support program (EMDS). We used EMDS to integrate a user-developed fuzzy logic knowledge base with a grid-based geographic information system to evaluate the degree of truth for assertions about a road's environmental impact. Using spatial data for natural and human processes in the Tahoe National Forest (TNF, California, USA), we evaluated the assertion "the road has a high potential for impacting the environment." We found a high level of agreement between the products of this evaluation and ground observations of a TNF transportation engineer, as well as occurrences of road failures. We used the modeled potential environmental impact to negatively weight roads for a least-cost path network analysis to 1573 points of interest in the forest. The network analysis showed that out of 8233 km of road analyzed in the forest, 3483 km (42%) must be kept in a modified road network to ensure access to these points. We found that the modified network had improved patch characteristics, such as significantly fewer "cherry stem" roads intruding into patches, an improved area-weighted mean shape index, and larger mean patch sizes, as compared to the original network. This analysis system could be used by any public agency to analyze infrastructure for environmental or other risk and included in other mandated analyses such as risks to watersheds.

Conservation of Natural Resources↗
PubMed1996

An automatic sleep-stage analysis system with off-line high-speed processing using a super mini-computer.

An automatic sleep analysis system using a super mini-computer was developed. The system improved and expanded the data processed by the mini-computer. It had the following features: 1) wave-forms were collected and analyzed at a high speed (reproduced at 10 or 20 times the speed of a data recorder) by an off-line procedure to utilize the computer resources more efficiently; 2) all information and the original wave-forms were output to a laser printer because of the lower cost and more efficient arrangement of the data; 3) various wave-form parameters were measured by wave-form analysis; 4) the application program was based on general-purpose language; and 5) wave-form reanalysis and reconstruction of the logic was easily implemented for automatic evaluation of the sleep stages. Automatic analysis of the sleep stages was impossible for 15 of 1484 periods (20 sec per period) with one of the cases analyzed, and 142 of 1484 periods had to be corrected because of erroneous identification.

Adult↗
PubMed1985

An inexpensive microcomputer-based image-analysis system: novel applications to quantitative autoradiography.

We describe a relatively inexpensive, yet versatile and powerful microcomputer-based image-analysis system, and its applications to processing of deoxyglucose autoradiographic data. Images are acquired via a video camera mounted on a light microscope or a light box, and digitized in 40 ms to 512 X 512 picture elements with 8-bit resolution (256 gray levels). The bit-mapped image analysis hardware can provide up to 256 colors for pseudo-color coding, and virtually instantaneous readout of brightness values for densitometry. The system is controlled by an 8-bit S-100 bus microcomputer, providing flexibility and ease of expansion. In addition to pseudo-color coding and densitometry, we have developed programs for averaging of successive sections, image subtraction and quantitative reconstruction of different planes of section from serial autoradiograms.

Animals↗
PubMed2004

Systems literature analysis.

Systems literature analysis (SLA) is the literature-driven version of systems biology. It treats collections of scientific literature as a system of millions of interconnections between research parameters, such as genes, diseases, tissues, cell events, model organisms, experiment types, and reagents. SLA aims to replace the traditional keyword-based querying of literature databases, which return sorted lists of papers, with a systems-based approach that returns integrated networks of relationships. Major applications include literature-based discovery of novel targets that link, for example, previously unlinked diseases and phenotypes to common genes and cellular events, and experiment design.

Databases, Bibliographic↗
PubMed1988

System analysis of Phycomyces light-growth response with Gaussian white noise and sum-of-sinusoids test stimuli.

The sporangiophore (fruiting body) of the fungus Phycomyces modulates its elongation rate in response to changes in blue light intensity. This light-growth response of wild-type and behavioral mutant strains has been studied extensively by two methods of nonlinear system identification employing Gaussian white noise and sum-of-sinusoids test stimuli. Both methods are in the framework of the Wiener theory of nonlinear systems. The light-growth response is well described by the first-order Wiener G-functional; addition of the second-order functional improves the precision. The Wiener kernel of first-order resembles the light-growth response to a nonsaturating pulse stimulus. The second-order kernel indicates the nonlinear property of rectification. The kernels have been interpreted by system analysis methods in the frequency domain. A nonlinear dynamic model of the light-growth response has been developed from the kernels obtained by both methods. The model includes a nonlinear dynamic subsystem, including a squarer, followed by a linear dynamic subsystem (which, by itself, accounts for the first-order kernel). This parametric model has been used to evaluate light-growth response kernels under various conditions (viz. wavelength, temperature, and genetic strain). The kernels of single and double mutants have been analyzed jointly with a nonparametric model to reveal interactions among the products of eight genes that influence the light-growth response. The extent of interactions found suggests that these gene products function together in a molecular complex.

Light↗
PubMed2005

The Cancode interaction analysis system in the oncological setting: reliability and validity of video and audio tape coding.

Cancode is a computerized interaction analysis system developed for cancer consultations. This paper assesses its reliability and validity, and compares the use of audio versus video tape; by assessing 30 consultations between an actor and 10 oncologists. Weighted Kappa inter- and intra-rater scores ranged from 0.5 to 1.0 and 0.58-1.0, respectively, and use of video tape did not alter verbal coding. Factor analysis of verbal codes revealed two factors, 'verbal control' and 'verbal support'. Verbal and non-verbal doctor behavior differed by patient type ('verbal support' P = 0.007, 'verbal control' P = 0.004, 'Responsiveness' P = 0.000, and 'Immediacy' P = 0.000). Inter-doctor variation was noted for 'verbal support' (P = 0.000) and 'Relaxation' (P = 0.000). 'Responsiveness' was negatively correlated with 'verbal support' (-0.58) and 'verbal control' (-0.65). Cancode is reliable, valid and sensitive to doctors behavioral changes. For a more passive patient, the doctor may switch from a 'cure' to 'care' oriented consult, responding to psycho-social instead of informational needs.

Adult↗
PubMed1990

Stereotactic investigation of limbic epilepsy using a multimodal image analysis system. Technical note.

A methodology has been developed for stereotactic investigation of limbic epilepsy using an image-analysis system that simultaneously displays different structural and functional images of the brain. The validity and accuracy of this system were established with phantom studies. Surgical planning and electrode implantation are guided by stereotactic magnetic resonance imaging, digital subtraction angiography, and position emission tomography. This methodology provides the spatiotemporal relationship of cerebral structure and function necessary to identify seizure onset and propagation in human limbic system epilepsy.

Brain Mapping↗
PubMedDate not supplied

Reliability and variability in the measurement of interlimbal distance with a semiautomated video replay analysis system (SAVRAS).

This paper reports on the reliability and variability of a semi-automated, video replay and analysis system (SAVRAS) in determining interlimbal distance in patients with strabismus. Factors under investigation were: choice of observer, choice of video frame, patient age and patient state (awake or anesthetized). It was demonstrated that SAVRAS was a highly reliable and reproducible system. This system is currently in use to evaluate the relationship between the succinylcholine induced ocular position, under anesthesia, and the postoperative awake alignment.

Child, Preschool↗
PubMed2005

[Developmental changes in the Collis horizontal reaction analyzed using a three-dimensional video motion analysis system. I. Examination of techniques for inducing Collis horizontal reaction].

We used a three-dimensional video motion analysis system to evaluate techniques for inducing the Collis horizontal reaction in 46 infants (total 217 times) from 1-9 months old. Additionally, we examined the safety of different techniques for inducing the Collis horizontal reaction in 20 infants (total 66 times), from 1-3 months old, 40 times by holding the shoulder joint and 26 times by not holding the shoulder joint. Regardless of who performed the examination, the average height that induced the reaction increased from 24.3 to 34.6 cm and the average speed of reaction increased from 28.2 to 43.4 m/s as the age of the infants increased. Additionally, when the Collis horizontal reaction was induced in infants 1-3 months old by holding the shoulder joint of infants, the average fall angle of the head was 7.291 degrees and was not significantly larger than when the reaction was induced by not holding the shoulder joint, which resulted is an average fall angle of the head was 19.302 degrees. However, although the average speed to support the body increased, the fall angle of the head did not increase when the shoulder joint was held. The Collis horizontal reaction is usually not performed in early infancy before head control is acquired, because of the burden to neck caused by the fall of the head and the excess expansion of shoulder joint capsule. However these results suggest that when performing the Collis horizontal reaction in early infancy before head control is acquired, the Collis horizontal reaction can be safely performed by holding the shoulder joint, regardless of the skill of the diagnostician. Therefore, the Collis horizontal reaction is an excellent method to assess infant development, and can be performed at the usual infant health examinations.

Child Development↗
PubMed1990

Linear systems analysis of cutaneous type I mechanoreceptors.

Linear system transfer functions of Type I mechanoreceptor domes in hairy skin were extracted for study. The system input, defined in units of indentation depth, was a punctate, 85 Hz bandlimited colored noise indenting stimulus. The system output was a dome's afferent AP event stream. After digitally low-pass filtering the AP event stream to prevent aliasing, transfer and coherence function estimates were generated from spectral and cross spectral estimates of the sampled input and output signals. Transfer function magnitudes (receptor sensitivity) beyond 10 Hz could be well fit by a fractional exponent (0.35 +/- 0.10) of frequency, indicating fractional order differentiation. Transfer function phases were near 120 degrees for frequencies less than 10 Hz and decreased progressively beyond 10 Hz. Coherence function estimates were low as a result of inherent nonlinearities, primarily rectification. Single dome results closely matched those reported by French and Kuster [6] for the tactile spine of the cockroach, suggesting that in terms of spectral sensitivity the receptors have similar transduction mechanisms. However, nonlinear systems modeling techniques are required for a more complete system characterization.

Action Potentials↗
PubMed1995

Quality control of imprint and tissue section DNA ploidy analysis in image analysis systems utilizing cell culture-based control materials.

Currently, there are no standard controls available for quality control of DNA ploidy assays in image analysis systems. The authors have developed a system of controls based on cultured human cell lines that can mimic tissue sections and touch preparations. This allows for quality control for the entire process for DNA ploidy analysis from the initial cutting of the paraffin block or production of the touch preparation through fixation, staining, and interactive image analysis. The use of cell line controls rather than normal tissue is advantageous because of cell population homogeneity and the volume of uniform slides that are obtainable. This system, while providing an excellent means of controlling day-to-day performance of DNA ploidy analysis, may also be adapted for use as a means of multi-institutional proficiency testing.

Cytological Techniques↗
PubMed2003

On-line prediction of yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score using the MARC beef carcass image analysis system.

The present experiment was conducted to evaluate the ability of the U.S. Meat Animal Research Center's beef carcass image analysis system to predict calculated yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score under commercial beef processing conditions. In two commercial beef-processing facilities, image analysis was conducted on 800 carcasses on the beef-grading chain immediately after the conventional USDA beef quality and yield grades were applied. Carcasses were blocked by plant and observed calculated yield grade. The carcasses were then separated, with 400 carcasses assigned to a calibration data set that was used to develop regression equations, and the remaining 400 carcasses assigned to a prediction data set used to validate the regression equations. Prediction equations, which included image analysis variables and hot carcass weight, accounted for 90, 88, 90, 88, and 76% of the variation in calculated yield grade, longissimus muscle area, preliminary yield grade, adjusted preliminary yield grade, and marbling score, respectively, in the prediction data set. In comparison, the official USDA yield grade as applied by online graders accounted for 73% of the variation in calculated yield grade. The technology described herein could be used by the beef industry to more accurately determine beef yield grades; however, this system does not provide an accurate enough prediction of marbling score to be used without USDA grader interaction for USDA quality grading.

Animals↗
PubMed1991

System analysis in multiple dose kinetics: evidence for saturable tubular reabsorption of the organic cation N1-methylnicotinamide in humans.

The renal clearance of N1-methylnicotinamide (NMN) was studied in 8 young women at physiological steady state and at steady state following a combined loading bolus and iv infusion. Urinary NMN concentrations were determined using a new HPLC method, plasma levels by a conventional fluorescence method. At physiological levels net tubular secretion of NMN was evident due to a renal fractional excretion, i.e., a ratio of renal NMN clearance to creatinine clearance, above unity. Increasing plasma concentrations lead to an increase in the fractional excretion, indicating saturation of the underlying tubular reabsorption process. Binding to plasma proteins was excluded by ultra-filtration experiments. Clearances measured at physiological levels were about one half of the maximum renal clearance attained following the infusion. This maximum value was approximately six times the creatinine clearance and may be a useful approximation of the renal plasma flow. System analysis, including a novel method to calculate the net response following a multiple input, was used to determine the pharmacokinetic system parameters.

Absorption↗
PubMed1981

Thionine-Feulgen-Congo red staining of cervical smears for the BioPEPR image-analysis system.

A staining method developed for use with BioPEPR (Biological Precision Encoding and Pattern Recognition), an automated image-analysis system for cervical smears, is described. The stain is a combination of the Feulgen procedure, with thionine-SO2 as the Schiff reagent, and Congo red, which is used as a counterstain. The stain resulted in smears suitable both for microscopic diagnosis and for BioPEPR measurements made on photonegatives at a single wavelength 545 nm. A high level of reproducibility and accuracy of nuclear and cytoplasmic area measurements was obtained. Nuclear integrated optical density could be well measured and was shown to be useful in discriminating between normal and abnormal cells. Using a combination of morphologic features, a high level of cell classification accuracy was reached. The possibility of using the stain for more detailed studies is discussed.

Autoanalysis↗
PubMed1992

Speech analysis systems: an evaluation.

Performance characteristics are reviewed for seven systems marketed for acoustic speech analysis: CSpeech, CSRE, ILS-PC, Kay Elemetrics model 5500 Sona-Graph, MacSpeech Lab II, MSL, and Signalyze. The characteristics reviewed include system components, basic capabilities (signal acquisition, waveform operations, analysis, and other functions), documentation, user interface, data formats and journaling, speed and precision of spectral analysis, and speed and precision of fundamental frequency analysis. Basic capabilities are also tabulated for three recently introduced systems: the Sensimetrics SpeechStation, the Kay Elemetrics Computerized Speech Lab (CSL), and the LSI Speech Workstation. In addition to the capability and performance summaries, this article offers suggestions for continued development of speech analysis systems, particularly in data exchange, journaling, display features, spectral analysis, and fundamental frequency analysis.

Diagnosis, Computer-Assisted↗
PubMed2005

A systems analysis of the Ladbroke Grove rail crash.

On 5 October 1999, near London Paddington Station, two trains collided on a main line near Ladbroke Grove. The immediate "human error" that preceded this crash was a Signal Passed At Danger (SPAD). Thirty-one people lost their lives and many more were injured. The crash prompted an extensive multi-disciplinary investigation and hearing to identify the factors that contributed to the Signal Passed At Danger event. This included the involvement of psychologists to consider the human factors "responsible" for the crash and the broader system context, including the operational and organizational environment that may have contributed. This paper summarizes the key factors identified in relation to this crash within a system analysis framework. This framework considers multiple sources of influence upon the driver in relation to the committed Signal Passed At Danger. These influences include direct factors attributable to the driver and the immediate circumstances of the event, as well as indirect, or latent, factors within the operational procedures and the management of the organization. This systemic combination of factors, not an isolated case of human error, conspired to propagate the events that resulted in the Signal Passed At Danger event and subsequent crash. This particular case demonstrates that train crashes cannot be distilled to a single causal factor. Rather, such crashes result from a system failure in which unpredicted interactions between direct and indirect influences coincide at an inopportune instant.

Accident Prevention↗
PubMedDate not supplied

An image analysis system for the quantification of invasion in vitro.

We have tested the value of a computer-assisted image analysis program for the quantitative study of invasion in vitro using experiments that were previously described semi-quantitatively. Mouse fibrosarcoma cell (MO4) aggregates were confronted with precultured fragments of embryonic chick heart in organ culture. Confronting pairs were fixed after 1, 2, 3 and 4 days, and processed for paraffin sectioning and immunostaining with an antiserum against chick heart. The image analysis system allowed separate quantification of two aspects of invasion, namely, occupation of the heart tissue by MO4 cells and degeneration of the invaded heart tissue. Complex combination of occupation and invasion added a qualitative aspect of invasion that has not been described previously and that revealed qualitative differences in invasion under various circumstances.

Animals↗
PubMed1990

The role of the reciprocal apparatus in the hind limb of the horse investigated by a modified CODA-3 opto-electronic kinematic analysis system.

The function of the reciprocal apparatus in the hind limb of the horse was studied by kinematic gait analysis. For recording purposes a modified opto-electronic CODA-3 kinematic analysis system was used. The raw kinematic data were corrected for skin displacement artifacts by use of recently developed correction models. It was concluded that contradictory findings about the coupling of tarsal and stifle joints by the reciprocal apparatus, when comparing in vitro and in vivo studies, can be fully attributed to artifacts due to the movement of the skin markers over the underlying bony structures, occurring in the in vivo experiments.

Animals↗