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 703 records · Page 39Linked to original sources
PubMedDate not supplied

Benchmarking the MCNP code for Monte Carlo modelling of an in vivo neutron activation analysis system.

The Monte Carlo computer code MCNP (version 4A) has been used to develop a personal computer-based model of the Swansea in vivo neutron activation analysis (IVNAA) system. The model included specification of the neutron source (252Cf), collimators, reflectors and shielding. The MCNP model was 'benchmarked' against fast neutron and thermal neutron fluence data obtained experimentally from the IVNAA system. The Swansea system allows two irradiation geometries using 'short' and 'long' collimators, which provide alternative dose rates for IVNAA. The data presented here relate to the short collimator, although results of similar accuracy were obtained using the long collimator. The fast neutron fluence was measured in air at a series of depths inside the collimator. The measurements agreed with the MCNP simulation within the statistical uncertainty (5-10%) of the calculations. The thermal neutron fluence was measured and calculated inside the cuboidal water phantom. The depth of maximum thermal fluence was 3.2 cm (measured) and 3.0 cm (calculated). The width of the 50% thermal fluence level across the phantom at its mid-depth was found to be the same by both MCNP and experiment. This benchmarking exercise has given us a high degree of confidence in MCNP as a tool for the design of IVNAA systems.

Body Composition↗
PubMed1984

BIOLOG - a DNA sequence analysis system in PROLOG.

BIOLOG contains facilities for the analysis of nucleic acid sequences. These facilities are available through queries and commands of the underlying implementation language PROLOG. Familiarity with PROLOG is gained by using the built-in BIOLOG functions. This experience should enable the user to extend the current system and define new facilities.

Amino Acid Sequence↗
PubMed1992

Intraobserver and interobserver reproducibility of the Nidek EAS-1000 Anterior Eye Segment Analysis System.

The NIDEK EAS-1000 is a camera and computer system designed to facilitate measurement and analysis of the anterior segment of the eye. To evaluate the interobserver reproducibility of the system, three examiners assessed the anterior chamber depth and peripheral angle measurement in 20 disease-free eyes. Intraobserver reproducibility was determined by each investigator's photographing and analyzing the same eye on three different occasions. Interobserver correlation for the anterior chamber depth (using the first three readings of the same eye made by each examiner) was 0.97, with an 95% CI of 0.94 to 0.98. Interobserver correlation for angle measurement (again using the first three readings of the same eye made by each examiner) was 0.89, with a 95% confidence interval (CI) of 0.81 to 0.95. Intraobserver correlations for anterior chamber depth were 0.98 for each of the three examiners (mean, 0.98), wiht a 95% CI of 0.91 to 0.99. Intraobserver correlations for anterior chamber depth were 0.98 for each of the three examiners (mean, 0.98), with a 95% CI of 0.91 to 0.99. The intraobserver CI for angle measurement was 0.97 (range, 0.95 to 0.99). The intraobserver and interobserver reproducibility of the NIDEK EAS-1000 system was excellent.

Adult↗
PubMed1988

Eco-systemic analysis of anorexia nervosa.

Aspects of the eco-systemic approach were used to provide a framework for the understanding of anorexia nervosa and were empirically tested by comparing 30 anorexics and their parents to 34 matched control subjects and their parents. The theoretical model employed was an adaptation of Conger's Ecological-Systems approach which was based on the principles of Bronfenbrenner's theory of human development. The subjects were compared on selected variables arising from the individual, parent, family, and community systems using (a) the California Psychological Inventory (CPI), (b) the Structural Analysis of Social Behavior (SASB), (c) the Family Environment Scale (FES), and (d) the Pattison Psychological Inventory (PPI). Discriminant analysis revealed that the Affiliation score (SASB) for the anorexic and the control subjects and the Psychopathic Deviancy score (CPI-Clinical) of the mothers of the anorexics and the controls were the variables which contributed most to the discrimination between the groups. With the Affiliation and the Psychopathic Deviancy scores alone, it was possible to correctly classify 87.5 per cent of the research subjects. Analyses also showed statistically significant results at the individual, parent, and family levels. Interactions within the family, as perceived by the anorexics, were characterized by overprotection and control by the mothers, while the anorexics themselves responded with significantly less affiliation to both their mothers and their fathers. The mothers of the anorexics also viewed their daughters as being less friendly in the relationship. The families of the anorexics were less supportive, helpful, and committed to each other than were the families of the control subjects as measured by the FES.

Adolescent↗
PubMed2003

PACRAT: a database and analysis system for archaeal and bacterial intergenic sequence features.

Analysis of intergenic sequences for purposes such as the investigation of transcriptional signals or the identification of small RNA genes is frequently complicated by traditional biological database structures. Genome data is commonly treated as chromosome-length sequence records, detailed by gene calls demarcating subsequences of the chromosomes. Given this model, the determination of non-called subsequences between any gene and its nearest neighbors requires an exhaustive search of all gene calls associated with the chromosome. Further compounding the issue, the location of intergenic regions for many called genes cannot be resolved unambiguously due to uncertainties in gene boundaries, as well as the presence of other conflicting gene calls. To address these difficulties we have constructed the PACRAT (http://www.biosci.ohio-state.edu/~pacrat/) database system. PACRAT preprocesses GenBank genome submissions, evaluates for every gene the character of its relationship to those genes nearest to it, and produces a relationally linked model of the gene ordering for the genome. Using this information, the interface allows the researcher to query gene data as well as intergenic sequence data based on a number of criteria. These include the ability to filter searches based on the status of start and stop positions, or upstream/downstream sequences as conflicting with called genes and automated extension of upstream or downstream searches to find probable operon promoters or terminators. The database is also indexed by KEGG classification, allowing, for example, functionally-related groups of high-quality promoter-containing regions to be easily retrieved as a group.

DNA, Archaeal↗
PubMed1993

Improved high-performance liquid chromatographic analysis of 8-methoxypsoralen monoadducts and cross-links in polynucleotide, DNA, and cellular systems: analysis of split-dose protocols.

The distribution of 8-methoxypsoralen-thymidine photoadducts from polynucleotides, calf thymus DNA and mammalian cells treated with [3H]8-methoxypsoralen under a variety of irradiation conditions was determined using high-performance liquid chromatography and scintillation analysis. The split-dose protocol, with samples treated with 8-methoxypsoralen and low doses of long-wavelength UV radiation to generate monoadducts, washed to remove unreacted 8-methoxypsoralen, then irradiated further to convert the monoadducts to cross-links, was examined. The photoadduct distribution in the first step is dependent upon the UVA dose and the wavelength of the radiation, but it is relatively independent of 8-methoxypsoralen concentration. Low fluence and longer wavelengths generate mainly 4',5'-monoadducts, whereas higher fluences and shorter wavelengths yield more cross-links. The second irradiation step converts the 4',5'-monoadducts to cross-links as well as to 3,4-monoadducts. The overall yield of cross-links after the second irradiation step is not dependent upon the wavelength used in the first step. Cellular studies demonstrated that the split-dose protocol is applicable to mammalian systems. These results may affect the interpretation of mutagenesis studies based on the split-dose protocol, because the second step can convert 4',5'-monoadducts to both 3,4-monoadducts, the expected cross-links. Therefore, interpretations that link increases in mutagenicity after the second step in a split-dose study solely to cross-link formation may need re-examination.

Animals↗
PubMed2006

SpotWhatR: a user-friendly microarray data analysis system.

SpotWhatR is a user-friendly microarray data analysis tool that runs under a widely and freely available R statistical language (http://www.r-project.org) for Windows and Linux operational systems. The aim of SpotWhatR is to help the researcher to analyze microarray data by providing basic tools for data visualization, normalization, determination of differentially expressed genes, summarization by Gene Ontology terms, and clustering analysis. SpotWhatR allows researchers who are not familiar with computational programming to choose the most suitable analysis for their microarray dataset. Along with well-known procedures used in microarray data analysis, we have introduced a stand-alone implementation of the HTself method, especially designed to find differentially expressed genes in low-replication contexts. This approach is more compatible with our local reality than the usual statistical methods. We provide several examples derived from the Blastocladiella emersonii and Xylella fastidiosa Microarray Projects. SpotWhatR is freely available at http://blasto.iq.usp.br/~tkoide/SpotWhatR, in English and Portuguese versions. In addition, the user can choose between "single experiment" and "batch processing" versions.

Blastocladiella↗