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At least 919 records · Page 51Linked to original sources
PubMed1997

[On-site laboratory monitoring on the intensive care unit. Blood gas, electrolyte, glucose, hemoglobin and lactate determination with the CIBA Corning 865 Analysis System].

INTRODUCTION: For decision-making in the ICU, rapid and accurate analysis of vital laboratory parameters is essential. The industry provides devices which analyse these parameters on a decentralised setting and which are designed for use by non-laboratory personnel. We investigated whether accuracy and handling of a new analyser (Ciba-Corning 865, Chiron Diagnostics, Medfield, USA) are good enough for basing clinical decisions on the measured parameters. MATERIALS AND METHODS: The Ciba-Corning 865 allows measurement of blood gases, electrolytes, haemoglobin, glucose and lactate by use of photometric, ion-selective, enzymatic and electrochemical sensors in less than 18 microliters of whole blood. In a cardiac surgical intensive-care unit the accuracy of the device was tested by comparison to 61 measurements of quality control reagents, 48 tonometered blood samples and 536 parallel measurements in the clinical laboratory. Besides a 10-minute instruction, the participating personnel had no formal training with the device. RESULTS: The differences between measurements in quality control reagents and tonometered blood and the expected value were lower than 5%. The comparison with clinical laboratory measurements showed correlation coefficients from 0.94 (sodium) to 0.99 (glucose, lactate). The biases in Bland-Altman analyses were below 5%, the limits of agreement were found to be in a clinically acceptable range for all parameters. During the test period no technical problems occurred with the analyser and good acceptance by the personnel was found. CONCLUSIONS: The measured parameters were accurate enough to be used for therapeutic decisions in acute care medicine. Although it should not be a complete alternative to the clinical laboratory, because of rapid analyses, small sample volumes and easy handling the use of the Ciba-Corning 865 is advantageous for patients and users.

Blood Chemical Analysis↗
PubMed1996

Nursing information management and processing: a framework and definition for systems analysis, design and evaluation.

This paper discusses a new framework and definition for the development of nursing information systems. Graves and Corcoran presented a framework for nursing informatics and defined the science. In this article their framework is expanded to include nursing practice as domain of study and to better integrate the fact that nursing informatics finds its foundation in both the nursing and the informatics disciplines. The expansion is based on both the review of definitions of medical and nursing informatics and of models and descriptions from the informatics discipline. For research purposes, the domain of nursing informatics is defined, and methods for conducting investigations in the area of analysis, modeling and development of nursing information systems are described.

Computer Simulation↗
PubMed1996

Validation of a 3D optoelectronic motion analysis system for the wrist joint.

OBJECTIVE: A study was undertaken to determine the experimental accuracy of a non-invasive optoelectonic 3-dimensional tracking system in assessing wrist joint motion. DESIGN: This was an in vivo experimental study involving volunteer subjects performing prescribed wrist motions. BACKGROUND: Current clinical practice does not include routine kinematic analysis for evaluating arthritic disease state, although motion disorders are common. METHODS: Surface markers were applied to 24 subjects assigned two hand postures in a test-retest factorial design for the expected range of motion. The marker positions were measured optoelectronically and using calibrated stereoradiography, to determine the positions of the surface markers and of key bone landmarks. Alignment and motion were compared for the three measurement techniques. Standard kinematic analyses were performed to extract Euler angles and equivalent screw displacement axes for paired postures. RESULTS: The three measurement techniques were highly correlated for wrist flexion-extension. Uncertainties were less than 6 degrees, similar to uncertainties from bone landmark identification errors when implanted markers cannot be used. Measures of motion exhibited higher correlations than those for alignment. Equivalent screw displacement axis orientations had poor intraclass correlations, reflecting sensitivity to coordinate system definitions. CONCLUSIONS: For motion analysis in the wrist in vivo, a non-invasive optoelectronic measurement system is as accurate as stereoradiographic analysis of bone segments.

Journal Article↗
PubMed1997

A Pentium personal computer-based craniofacial three-dimensional imaging and analysis system.

Personal computer (PC)-based computing is now ubiquitous in common consumer applications. Although PCs have equaled or surpassed engineering workstations in basic computing power and economy, there is still strong workstation dependency for imaging applications. This article demonstrates that a complete system, based on a Pentium PC (Intel Corporation, Santa Clara, CA) and readily available and inexpensive software, can be built very economically for effective execution of most of the commonly used three-dimensional imaging operations. For the craniofacial application, the Pentium system offers a twofold speed advantage over a Sparc 20 system using similar three-dimensional processing software. The Pentium system allows interactive fuzzy volume rendering, and manipulation and analysis of complex hard and soft-tissue structures.

Equipment Design↗
PubMed2004

A model for analysis, systemic planning and strategic synthesis for health science teaching in the Democratic Republic of the Congo: a vision for action.

BACKGROUND: The problem of training human resources in health is a real concern in public health in Central Africa. What can be changed in order to train more competent health professionals? This is of utmost importance in primary health care. METHODS: Taking into account the level of training of secondary-level nurses in the Democratic Republic of the Congo (DRC), a systemic approach, based on the PRECEDE PROCEED model of analysis, led to a better understanding of the educational determinants and of the factors favourable to a better match between training in health sciences and the expected competences of the health professionals. This article must be read on two complementary levels: one reading, focused on the methodological process, should allow our findings to be transferred to other problems (adaptation of a health promotion model to the educational sphere). The other reading, revolving around the specific theme and results, should provide a frame of reference and specific avenues for action to improve human resources in the health field (using the results of its application in health science teaching in the DRC). RESULTS: The results show that it is important to start this training with a global and integrated approach shared by all the actors. The strategies of action entail the need for an approach taking into account all the aspects, i.e. sociological, educational, medical and public health. CONCLUSIONS: The analysis of the results shows that one cannot bring any change without integrated strategies of action and a multidisciplinary approach that includes all the complex determinants of health behaviour, and to do it within the organization of local structures and institutions in the ministry of health in the DRC.

Journal Article↗
PubMed2004

Systemic analysis of structures and contents of nitrogen-containing compounds and other non-hydrocarbons in crude oils in conjunction with chemometric resolution technique.

A method is described for the systemic identification and quantitative analysis of nitrogen-containing compounds and other non-hydrocarbons in crude oils. The pre-fractionation of a crude oil sample into 7 fractions was performed by di-adsorption column chromatography using neutral aluminum oxide and silica gel. A subsequent high-resolution separation of individual components was achieved by using capillary column gas chromatography, and compound types were detected by a mass spectrometer. In conjunction with a chemometric method, the compounds in the fractions were further resolved or separated, which made it possible to identify some nitrogen-containing compounds and other non-hydrocarbons in crude oils. To a certain extent, this method could relieve the difficulty of classical analysis in identifying those species with very low contents or incompletely separation, particularly in the cases where authentic standards were not available for addition into the unknown samples in order to reveal what indeed existed in them. The structures and contents of 168 nitrogen-containing compounds in one crude sample and 60 non-nitrogen-containing compounds in one of non-hydrocarbon fractions of this oil sample were determined, and the addition-recovery examination of some standard compounds showed that the analytical veracity was satisfactory.

Journal Article↗
PubMedDate not supplied

EvIdent: a functional magnetic resonance image analysis system.

EvIdent (EVent IDENTification) is a user-friendly, algorithm-rich, exploratory data analysis software for quickly detecting, investigating, and visualizing novel events in a set of images as they evolve in time and/or frequency. For instance, in a series of functional magnetic resonance neuroimages, novelty may manifest itself as neural activations in a time course. The core of the system is an enhanced variant of the fuzzy c-means clustering algorithm. Fuzzy clustering obviates the need for models of the underlying requisite biological function, models that are often statistically suspect.

Algorithms↗
PubMed1999

[A computer-aided analysis system for hypertensive retinal image and its clinical application].

With the use of computer image processing technology and microcirculational network analysis technology, we have developed a new system to analyze the outlook of retinal vessles quantitatively. A multimedia structure has been designed for patient's case history file, which includes the basic information of patients, the operating information during sampling and processing patient's retinal image and the result. The system includes image sampling, image displaying, image processing, parameters measuring and analyzing, reports printing and atlas management. Clinical application indicates that the system is useful to hypertension diagnosis.

Aged↗
PubMedDate not supplied

Development of the specific purpose Monte Carlo code CEARXRF for the design and use of in vivo X-ray fluorescence analysis systems for lead in bone.

X-ray fluorescence (XRF) systems have been increasingly used for in vivo toxic trace-element analysis in the human body, such as lead in the tibia. Monte Carlo simulation can provide an efficient and flexible method for designing and using in vivo XRF systems. The Monte Carlo code CEARXRF has been developed specifically to simulate the complete pulse height spectrum of energy-dispersive XRF systems. This code is capable of tracking photons in a general geometry and modelling all of the physics of photon interactions in the energy range 1-150 keV for elements Z = 1-94, including primary and higher degree excitations of K and L XRF, the Doppler broadening of Compton-scattered photon energies, and the polarization effects in low-energy photon scatterings. The scattering background for minimum detectable concentration (MDC) analysis may be simulated more accurately by taking into account Doppler broadening in the distribution of the Compton-scattered photon energy due to electron-binding effects. The use of polarized excitation photons has been shown to be important in producing a low scattering background and good measurement sensitivity. The code has two very unique and important features: (1) complete composition and density correlated sampling that is extremely useful for studying measurement sensitivity to small changes in sample composition and density; and (2) Monte Carlo library spectra calculation for the determination of elemental amounts by the Monte Carlo-Library Least-Squares (MCLLS) method. The capability of CEARXRF to aid the design and optimization of in vivo XRF analysis has been verified by modelling hypothesized lead K and L XRF measurement systems.

Bone and Bones↗
PubMed1984

Echocardiogram processing and classification using data-dependent systems analysis.

This paper presents results of a study on M-mode echocardiogram analysis and classification using the recently developed data-dependent system (DDS) methodology along with clustering techniques. Results of thirty clinically obtained waveforms yielded a correct classification rate of between 83% and 90%, depending on the features used for clustering. The choice of features was facilitated, in part, by a study of six hypothetical waveforms representing an echocardiogram in transition from normal to stenosed. The DDS approach offers potential in the identification and recognition of various cardiac abnormalities, based on echocardiographic data. A comparison with Fourier analysis confirmed the results and points to the advantages of DDS in (a) minimizing false negatives and (b) providing additional features for improved discrimination.

Adolescent↗
PubMed2006

Determination of mercury in fish by cold vapor atomic absorption spectrophotometry using a multicommuted flow injection analysis system.

A flow system was developed for the determination of total mercury concentration in fish samples by cold vapor atomic absorption spectrophotometry (CVAAS), based on the multicommuted flow injection analysis (MCFIA) approach. The system uses independently controlled solenoid valves for the introduction of reagents and samples. When not injected, solutions were recirculating to the reservoir bottles, in this way reducing the waste produced by the analytical system and also the sample consumption. Results were compared to those obtained by the reference flow injection procedure. Accuracy was also assessed by recovery studies using a certified reference material as well as spiked samples; recovery percentages in the range of 90.7% to 99.8% were found. The repeatability of the method was better than 6.0% (RSD, n = 10). A limit of detection of 4.8 microg of mercury per kg of fresh fish sample was achieved. The total waste produced was reduced to 30% of that from the reference flow injection CVAAS procedure.

Animals↗
PubMed1988

Description, validation, and performance characteristics of a new computer-automated sperm motility analysis system.

A computer-automated sperm motility assay (CASMA) system has been developed that provides a rapid and accurate analysis of multiple sperm movement parameters and a new measure of linearity, the linear deviation angle. CASMA provides objective, unbiased sampling and accurate quantitation of the movement characteristics of 200 sperm cells in 20 min. It consists of a microscope-mounted video camera, a high-resolution video disk recorder, a video digitizer/memory board mounted in an IBM 9000 microcomputer, and newly developed software. After manual recording, at 60 frames/s, of the video sequences (takes) of sperm suspensions, each take is automatically played back frame by frame, digitized, and stored in video memory. The software searches each frame, recognizes sperm cells, randomly selects a preset number for analysis, and traces each cell through the sequence to generate sperm "tracks" that are then stored in disk memory. This process is repeated for each take. Analysis of the stored tracks of each take yields the mean +/- SEM of the standard sperm motility parameters: percent motile (%M), curvilinear velocity (VC), net velocity (Vn), position-averaged velocity (Va), linear index (Vn/Va), progressiveness ration (Vn/Vc), and curvilinear progressiveness ratio (Va/Vc). Additionally, CASMA allows measurement of the linear deviation angle, a more direct measure of the linearity of sperm movement. For statistical comparisons, multiple takes can be considered either as replicates or separate experimental determinations. Finally, for more detailed analysis, each individually stored track, with its associated parameters, or histogram distributions of all sperm for each parameter can be displayed and printed. The performance of CASMA was evaluated by comparison of CASMA-determined movement parameters with manually determined values derived from the same sperm cells in the same video sequence and by comparison with published values determined using microcinematographic techniques. In each case, the CASMA values were essentially identical to those determined by manual measurements. Finally, CASMA accurately quantitates the linearity of sperm movement, a characteristic previously determined only by much more time-consuming methods. CASMA is a rapid and accurate system for measuring washed bull sperm motility and has reliably analyzed monkey and elephant sperm. The system has the potential to quantitate motility equally well with sperm from any species that have similar sperm head size.

Animals↗
PubMed2000

Biochemical systems analysis of genome-wide expression data.

MOTIVATION: Modern methods of genomics have produced an unprecedented amount of raw data. The interpretation and explanation of these data constitute a major, well-recognized challenge. RESULTS: Biochemical Systems Theory (BST) is the mathematical basis of a well-established methodological framework for analyzing networks of biochemical reactions. An existing BST model of yeast glycolysis is used here to explain and interpret the glycolytic gene expression pattern of heat shocked yeast. Our analysis demonstrates that the observed gene expression profile satisfies the primary goals of increased ATP, trehalose, and NADPH production, while maintaining intermediate metabolites at reasonable levels. Based on a systematic exploration of alternative, hypothetical expression profiles, we show that the observed profile outperforms other profiles. CONCLUSION: BST is a useful framework for combining DNA microarray data with enzymatic process information to yield new insights into metabolic pathway regulation. AVAILABILITY: All analyses were executed with the software PLAS(Copyright), which is freely available at http://correio.cc.fc.ul.pt/~aenf/plas.html for academic use. CONTACT: VoitEO@MUSC.edu

Computational Biology↗
PubMed2005

Separation of human serum proteins using the Beckman-Coulter PF2D system: analysis of ion exchange-based first dimension chromatography.

The ProteomeLab PF2D protein fractionation system is a rapid, semi-automated, 2 D-HPLC instrument that uses two different methods to separate plasma serum proteins: ion-exchange chromatography using a wide pH range in the first dimension, and non-porous reverse-phase chromatography in the second dimension. Because this methodology has only very recently been introduced in proteomic laboratories, little is known about the characteristics of PF2D fractionation of human serum proteins. To evaluate the system's application in a clinical laboratory setting, the characteristics of the ion-exchange chromatography-based separation were analyzed. Following fractionation of human serum proteins on a linear pH gradient (ranging from 8.0 to 4.0), each fraction was collected in a cool module of the instrument. Different fractions obtained from the first dimension were then pooled together and loaded on classic 2D gel electrophoresis instrumentation. The different spots obtained were then checked against the Swiss-Prot Data-base. A total of 36 human serum proteins were identified in different PF2D-generated fractions. Some important features of the separation system were observed. Different eluted fractions contained different proteins, thus demonstrating the reliability of the fractionation system. The proteins were also fractionated according to the theoretical isoelectric point (pI). This was consistent with the evidence that the vast majority of immunoglobulins, characterized by an alkaline pI, were not retained by the column and were eluted in the unbound fraction. This outcome also underlines a practical advantage: fractions eluted from pH 8 to pH 4 contained virtually immunoglobulin-depleted serum proteins. This finding supports an immediate use of the PF2D system in a clinical setting, where abundant proteins should be clearly identified to enable evaluation of other less abundant, but potentially relevant, species.

Automation↗
PubMed1999

Optimized dairy grazing systems in the northeast United States and New Zealand. II. System analysis.

Factors that optimize milk production from Northeast United States and New Zealand grazing systems are compared using a linear programming model. The objective function maximized gross margin per hectare of land farmed. The experimental design compared the optimum characteristics of each system over a range of milk prices. The Northeast has a shorter grazing season and lower cropping costs than New Zealand. The optimum pasture area was 49% of the farm for Northeast systems. Gross margins declined rapidly above 55% or below 36% pasture area. The optimum stocking rate was 1.13 cows/ha, or 2.3 cows/ha of pasture. Optimum per cow production was higher for Northeast [7105 kg of fat-corrected milk (FCM)] than New Zealand (5710 kg of FCM) systems. This was related to lower grain relative to milk prices in the Northeast. New Zealand, all-pasture systems gave the lowest cost per unit of milk but also gave the lowest gross margin across all milk price scenarios. The best use of purchased feed in New Zealand systems was to support increased stocking rate rather than per cow production. Optimum grazing management practices were similar for supplemented New Zealand and Northeast systems. All-pasture New Zealand systems are characterized by short lactations and long autumn rotations to transfer pasture in situ for winter feeding. Higher costs per unit of milk produced will be an inevitable consequence of maximizing gross margin at high milk prices in New Zealand systems.

Agriculture↗
PubMed1977

A systems analysis of the impact of physician extenders on medical cost and manpower requirements.

This paper presents a descriptive narrative of a mathematical manpower model and the results of an analysis of the effect physician extenders have on medical costs and manpower requirements. The model is extensively developed, through the use of a new medical classification system in the area of delegation of specific task areas and patient visits to physician extenders. Additionally the models incorporate a complete cost structure for a group practice. Field trials in seven HMOs indicate that the models accurately represent the actual system and can be used effectively as planning aids. Results are presented that analyze the use of physician extenders from the following viewpoints: minimum cost solution for adult medicine, pediatrics and obstetrics/gynecology (OB/GYN); maximum physician extender use; effect of physician extender salary on minimum cost utilization; level of independence exercised; size of clinic and regional manpower planning; and a case study of HMO planning. The type of results presented include cost analysis, manpower analysis, and the types of patient visits best delegated to physician extenders (PE).

Adult↗
PubMed1986

Systemic analysis of anticipating reactions.

A capacity for anticipating reactions realizes itself in the course of systemic activity formation, events. There is no doubt that probability of prediction proves to be possible on the basis of formation in brain structures of certain systems of anticipating excitations. Dynamics of EP analogues is an objective criterion of evaluation of the anticipating reaction central mechanisms. The term "EP analogue" conveys the phenomenon of reproduction of the EP configurations in intersignal spans. On the basis of analysis of EP analogue dynamics, we succeeded in following the process of brain structure organization into the anticipating intercentral integrations and also in elucidating the role that different afferentation redistributions play in this process by their functional significance.

Animals↗