PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Data Display”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

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

At least 361 records · Page 20Linked to original sources

PEPTY: a knowledge-based program for assisting medical reasoning in peptic diseases.

PEPTY is a program developed with the aim of providing a diagnostic and therapeutic assistance in managing peptic diseases. Its theoretical basis is an accurate analysis of current concepts in peptic disease diagnosis and treatment. This was done by reviewing recent literature and consulting skilled gastroenterologists. The decision tree includes three sections dealing with diagnostic, therapeutic and monitoring problems. The diagnostic section starts by evaluating clinical data from patient history and physical examination; the diagnostic hypotheses given at this level are refined and eventually confirmed by further information in the following section. Here the decision tree becomes modular in that a proper therapeutic and monitoring pathway is defined for four disease classes: gastroduodenal peptic ulcer and duodenitis, gastro-oesophageal reflux, erosive gastritis, and chronic antral gastritis. In the therapeutic section a cost-benefit analysis of possible therapeutic choices is always performed, but the final decision is made by the user. Complications, side effects and treatment efficacy are also considered and the program finally suggests the appropriate maintenance treatment. Patient data display, storage and retrieval, and explanation facilities are supplied. The system can provide a 'second opinion' in the medical practice and may be a useful learning tool for medical students.

Artificial Intelligence↗

A personal computer-based system for parallel line analysis of bioassay data.

A program is described for symmetric parallel line analysis of bioassay data with a logistic dose-response relationship. Dose-response relationship is transformed to semilog or log-log. A regression line can be calculated for the dose-response curve for standard and test samples, and produces potency estimate of test sample preparation relative to the standard preparation based on parallel-line bioassay statistical methods [3,4], together with detailed analysis of variance, estimates of slope, intercept and chi 2 test which permits a very sensitive test for linearity and parallelism of standard and test sample and facilitates detection of 'outliers', i.e. samples exhibiting non-parallelism. The general comparison of dose-response relationships produced by the program are a feature of particular interest.

Analysis of Variance↗

Neuron imaging with Neurolucida--a PC-based system for image combining microscopy.

Neurolucida is a new software package for performing 3-D neuron mapping and tracing to 0.5 micron precision through the oculars of a microscope. It incorporates computer controlled stage movement in three dimensions. Sections are limited in size only by the stage dimensions. An on-line, direct view image editor is provided as are dynamic image rotations in color and morphometric analyses. Neurolucida is written in 'C' and runs on PC ATs, XTs, and PS/2s using DOS and VGA, EGA, or NTSC graphics. Neurolucida has a video mode compatible with frame grabbers, thereby permitting its application to video microscopy.

Computer Graphics↗

Characterization of the main transition of dinervonoylphosphocholine liposomes by fluorescence spectroscopy.

The structural dynamics of the main phase transition of large unilamellar dinervonoylphosphocholine (DNPC) vesicles was investigated by steady state and time-resolved fluorescence spectroscopy of the membrane incorporated fluorescent lipid analog, 1-palmitoyl-2[10-(pyren-1-yl)]decanoyl-sn-glycero-3-phosphocholine (PPDPC). These data were supplemented by differential scanning calorimetry (DSC) and fluorescence anisotropy measured for 1-palmitoyl-2-(3-(diphenylhexatrienyl) propanoyl)-sn-glycero-3-phosphocholine (DPHPC). The collected data displayed several discontinuities in the course of the main transition and the pretransition. The discontinuities seen in the fluorescence properties may require modification of the existing models for phospholipid main transition as a first order process. From our previous study on dipalmitoylphosphocholine (DPPC), we concluded the transition to involve a first-order process resulting in the formation of an intermediate phase, which then converts into the liquid crystalline state by a second order process. Changes in the physical properties of the DNPC matrix influencing probe behavior were similar to those reported previously for PPDPC in DPPC. In gel state DNPC [(T-T(m))<-10] the high values for excimer/monomer emission ratio (I(e)/I(m)) suggest enrichment of the probe in clusters. In this temperature range, excimer fluorescence for PPDPC (mole fraction X(PPDPC)=0.02) is described by two formation times up to (T-T(m)) approximately -10, with a gradual disappearance of the fractional intensity (I(R1)) of the shorter formation time (tau(R1)) with increasing temperature up to (T-T(m)) approximately -10. This would be consistent with the initiation of the bilayer melting at the PPDPC clusters and the subsequent dispersion of the one population of PPDPC domains. A pronounced decrement in I(e) starts at (T-T(m))=-10, continuing until T(m) is reached. No decrease was observed in fluorescence quantum yield in contrast to our previous study on DPPC/PPDPC large unilamellar vesicles (LUVs) [J. Phys. Chem., B 107 (2003) 1251], suggesting that a lack of proper hydrophobic mismatch may prevent the formation of the previously reported PPDPC superlattice. With further increase in temperature and starting at (T-T(m)) approximately -1, I(e), tau(R2), and excimer decay times (tau(D)) reach plateaus while increment in trans-->gauche isomerization continues. This behavior is in keeping with an intermediate phase existing in the temperature range -1<(T-T(m))<4 and transforming into the liquid disordered phase as a second order process, the latter being completed when (T-T(m))-->4 and corresponding to approximately 50% of the total transition enthalpy.

Calorimetry, Differential Scanning↗

Advanced multimodal visualisation of clinical gait and fluoroscopy analyses in the assessment of total knee replacement.

Traditional gait and fluoroscopy analysis of human movement are largely utilised but are still limited in registration, integration, synchronisation and visualisation capabilities. The present work exploits the features of a recently developed software tool based on multimodal display (Data Manager developed within the EU-funded project 'Multimod') in an exemplary clinical case. Standard lower limb gait analysis, comprising segment position, ground reaction force and EMG data collection, and three-dimensional fluoroscopy analysis at the replaced joint were performed in a total knee replacement patient while ascending stairs. Clinical information such as X-rays and standard scores were also available. Data Manager was able to import all this variety of data and to structure these in an original hierarchical tree. Bone and prosthesis component models were registered to corresponding marker position data for effective three-dimensional animations. These were also synchronised with corresponding standard video sequences. Animations, video, time-histories of collected and also processed data were shown in various combinations, according to specific interests of the bioengineering and medical professionals expected to observe and to interpret this large amount of data. This software tool demonstrated to be a valuable means to enhance representation and interpretation of measurements coming from human motion analysis. In a single software, a thorough and effective clinical and biomechanical analysis of human motion was performed.

Arthroplasty, Replacement, Knee↗

Electrostatic effects on the yield stress of whey protein isolate foams.

The mechanisms responsible for foam structure are of practical interest within the food industry. The yield stress (tau) of whey protein isolate (WPI) foams as affected by electrostatic forces was investigated by whipping 10% (w/v) protein solutions prepared over a range of pH levels and salt concentrations. Measurements of foam overrun and model WPI interfaces, i.e. adsorption kinetics as determined via dynamic surface tension and dilatational rheological characterization, aided data interpretation. Interfacial measurements were also made with the primary whey proteins, beta-lactoglobulin (beta-lg) and alpha-lactalbumin (alpha-la). Yield stress of WPI foams was dependent on pH, salt type and salt concentration. In the absence of salt, tau was highest at pH 5.0 and lowest at pH 3.0. The addition of NaCl and CaCl2 up to 400 mM significantly increased tau at pH 7.0 but not at pH 3.0. Furthermore, at pH 7.0, equivalent molar concentrations of CaCl2 as compared to NaCl increased tau to greater extents. Salts had minimal effects on tau at pH 5.0. Comparisons with interfacial rheological data suggested the protein's capacity to contribute towards tau was related to the protein's potential at forming strong, elastic interfaces throughout the structure. The dynamic surface tension data for beta-lg and alpha-la were similar to WPI, while the interfacial rheological data displayed several noticeable differences.

Adsorption↗

Quantification of human motion: gait analysis-benefits and limitations to its application to clinical problems.

The technology supporting the analysis of human motion has advanced dramatically. Past decades of locomotion research have provided us with significant knowledge about the accuracy of tests performed, the understanding of the process of human locomotion, and how clinical testing can be used to evaluate medical disorders and affect their treatment. Gait analysis is now recognized as clinically useful and financially reimbursable for some medical conditions. Yet, the routine clinical use of gait analysis has seen very limited growth. The issue of its clinical value is related to many factors, including the applicability of existing technology to addressing clinical problems; the limited use of such tests to address a wide variety of medical disorders; the manner in which gait laboratories are organized, tests are performed, and reports generated; and the clinical understanding and expectations of laboratory results. Clinical use is most hampered by the length of time and costs required for performing a study and interpreting it. A "gait" report is lengthy, its data are not well understood, and it includes a clinical interpretation, all of which do not occur with other clinical tests. Current biotechnology research is seeking to address these problems by creating techniques to capture data rapidly, accurately, and efficiently, and to interpret such data by an assortment of modeling, statistical, wave interpretation, and artificial intelligence methodologies. The success of such efforts rests on both our technical abilities and communication between engineers and clinicians.

Biomechanical Phenomena↗

Null bar and null zone are better than the error bar to compare group means in graphs.

THE PROBLEM: Conventional graphs often include error bars around the group means. Regardless of what these bars depict, they are uninformative as to whether a difference between the groups is statistically significant. THE SOLUTION: This article suggests plotting the null bar or null zone: that is, the range or area in which the means of the two groups fall if the null hypothesis of no difference cannot be rejected. The bar and zone are simply derived from the confidence interval around the difference, obtained from the t-test.

Data Display↗

Computers in the ICU: where we started and where we are now.

The first use of computers in critical care units were described in the mid 1960s. They reported the use of very large mainframe computers that filled entire rooms yet had very limited memory and processing capacities by today's standards. These were limited to only a few institutions until microprocessors were developed increasing computation speed and expanding memory capacity by many magnitudes. This allowed smaller more affordable stand alone systems to be developed and the inclusion of microprocessors into bedside devices. As the capacity expanded uses broadened. Simple results review developed into a more complete electronic medical record. Databases were created allowing population analysis for research and systems quality improvement activities. Decision support started as simple alerting of potential errors and dangers and expanded into more sophisticated clinical decision-making support. With this came problems that needed solutions. As the amount of information became overwhelming to the bedside clinician, methods to filter and display data made it more useful. Security and confidentiality became major concerns. Data input solutions had to be found including interfaces between computers, bedside devices and instruments designed to automate data input like scanners, bar coders, and other devices. The biggest issue of all however, was developing acceptance among clinicians and creating the cultural change required for successful implementation of electronic medical records. This paper will explore these issues.

Computer Systems↗

StdpC: a modern dynamic clamp.

With the advancement of computer technology many novel uses of dynamic clamp have become possible. We have added new features to our dynamic clamp software StdpC ("Spike timing-dependent plasticity Clamp") allowing such new applications while conserving the ease of use and installation of the popular earlier Dynclamp 2/4 package. Here, we introduce the new features of a waveform generator, freely programmable Hodgkin-Huxley conductances, learning synapses, graphic data displays, and a powerful scripting mechanism and discuss examples of experiments using these features. In the first example we built and 'voltage clamped' a conductance based model cell from a passive resistor-capacitor (RC) circuit using the dynamic clamp software to generate the voltage-dependent currents. In the second example we coupled our new spike generator through a burst detection/burst generation mechanism in a phase-dependent way to a neuron in a central pattern generator and dissected the subtle interaction between neurons, which seems to implement an information transfer through intraburst spike patterns. In the third example, making use of the new plasticity mechanism for simulated synapses, we analyzed the effect of spike timing-dependent plasticity (STDP) on synchronization revealing considerable enhancement of the entrainment of a post-synaptic neuron by a periodic spike train. These examples illustrate that with modern dynamic clamp software like StdpC, the dynamic clamp has developed beyond the mere introduction of artificial synapses or ionic conductances into neurons to a universal research tool, which might well become a standard instrument of modern electrophysiology.

Action Potentials↗

Eye movements in reading isolated words: evidence for strong biases towards the center of the screen.

Three experiments were conducted that compared the eye movement pattern to a peripheral word or letter string as a function of the position of an initial fixation stimulus relative to the center of the screen and the straight-ahead position. Results revealed a strong bias of the eye behavior towards the center of the screen, but not towards the straight-ahead position. Saccades were greater in length, and landed closer to the center of words/strings when launched from a position left of center than when launched from either center or right part of the screen. In addition, the initial saccade launch site was deviated to the right, or to the left of the initial fixation stimulus depending on where relative to the center of the screen the fixation stimulus was displayed. Data were interpreted with the assumption that saccades are programmed in a visual reference framework, with saccade amplitude being computed in relative coordinates. Further research will determine whether the observed bias generalizes to text reading.

Adult↗

Wavelet transform system makes one-beat analysis possible in late potential evaluation.

High-frequency components of the QRS complex, including late potentials, can be analyzed by signal averaging (SA). However, this method may fail to detect transient changes as a result of cancellation. The wavelet transform, which has a superior time-frequency resolution, was used to analyze beat-to-beat changes of the QRS components in 50 normal subjects and 50 patients who showed positive late potentials. The transformed data, displayed in three dimensions and in color, were highly reproducible in each patient. Measurement of high-power duration at a frequency of 50 Hz (WD50) showed a significant correlation between WD50 and filtered QRS duration in both groups. When the mean +/- SD of WD50 in normal subjects was defined as normal, 96% of patients with late potentials were out of the normal range. The wavelet signals in patients with late potentials were more inhomogeneous than those of normal subjects. It is concluded that this newly developed color display, three-dimensional wavelet transform system showed extremely good time-frequency resolution in analyzing every beat without signal averaging.

Action Potentials↗

A model of DSB-repair kinetics.

A model of repair kinetics of DSB based on a step-by-step removal of individual double-strand breaks inside an autonomous repair unit is proposed and compared with the alternative model commonly used in modelling repair kinetics, which is based on an assumption of stochastic removal of cellular lesions. The former model seems to be preferred by the recently published experimental data displaying the time decrease of average DSB number per cell in irradiated Saccharomyces cerevisiae (strain 211 B) held in non-growth conditions.

DNA Repair↗

Pediatric interview assessment of child abuse. Challenges and opportunities.

The assessment of child abuse is a professionally and personally challenging task. Here as elsewhere in medicine success often is linked with the informed intelligence, mature attitude, and professional demeanor of the clinician. If one can maintain a thoughtful and skeptical approach to the data; display warmth, calm, and respect to everyone involved in the case; and express one's views with care and parsimony, good information will be forthcoming and, it is hoped, excellent management will follow.

Child↗

Speckle detection for 3D ultrasound.

Positioning accuracy of 3D ultrasound slice planes can be enhanced by speckle decorrelation of the B-scans. A suitable method requires accurate identification of zones of non-specular reflection in the image, a feature of parenchymal tissue. This has traditionally been achieved with statistics such as signal-to-noise ratios and measures of autocorrelation curves. Co-occurrence matrices and structural approaches have also been applied to ultrasound images. In this paper we assess the performance of these methods when only B-scan display data is available. We also report improved results with in vivo images using a proposed structural algorithm that detects speckle kernels. All detection algorithms yielded detection error rates between 28% and 38%, suggesting that user intervention may be required for clinically useful performance.

Algorithms↗

Statistical visualization for data exploration: a case study on Sydney Olympic Park.

Due to the powerful graphic interface in modern computers, visualization techniques have become more and more popular for data exploration. As a preliminary investigation, visualization is a greatly useful tool to lead to further statistical analysis and modelling. It is likely that historical environmental data from a range of different studies may contain useful information that should be assessed for determining management actions. However, these historical data are collected from many different studies, which have different space and/or time scales making the visualization process complicated. In this paper we present several ways of visualizing historical data based on a study at Sydney Olympic Park. The tools include spatial coverage and variation for different spatial resolutions, temporal coverage and time series plots for different time scales, multi-panel scatterplots for a small number of variables and "one-to-all" scatterplots for a large number of variables.

Computer Graphics↗

Surface ozone trends in Hong Kong in 1985-1995.

Ozone trends in Hong Kong were assessed from the ozone data recorded at three urban stations and one station in the new development area. Three parameters were selected as the robust trend indicators in the study: monthly mean, monthly averaged daily 1-h maximum, and number of annual hours > 120 microg m(-3). As the ozone data displayed obvious seasonal variation, using deseasonalized monthly average parameters to estimate the ozone trends could smooth out the influence of seasonal fluctuations. The detection of an increase of more than 10% per year in ozone concentration at one station was particularly alarming. Effects of meteorological factors, control programmes of ozone precursors, and long-range transport on the ambient ozone level were examined in the study.

Air Pollutants↗