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PubMedDate not supplied

[Higher mental functions and the systems analysis of behavior under conditions of uncertainty].

Superior psychical functions (skills) are usually formed in great subjective uncertainty conditions. Because of that exact knowledge of information mechanisms of behavior activity under uncertainty conditions is very importent. Some difficulties of traditional notions (classic behavior act model developed by P. K. Anokhin, systems quantization of behavior) are discussed. The model of probabilitive training allows to describe various training uncertainty conditions, and it operates as the Anokhin model in a specific case. The system-shaping factor in this model is an adaptive result. Afferent synthesis, aim for action, acceptor of the action result and the programme of actions have the traditional senses. Besides those it is proposed to use a concept of probability decision to alter the program of action, as well as an idea of memory buffer (results of search reactions). The organizational features of the functional system of behavior under great uncertainty conditions should be taken into account while specifying the informational mechanism responsible for systems quantization of behavior. The above mechanism can be used for explain the discreteness of an action in the program alteration process when the same quantum of behavior is implemented. These ideas are profitable for systems analysis of superior psychical functions, based on the reflex formation under environmental uncertainty conditions.

Animals↗
PubMed1982

Simultaneous Feulgen densitometry and autoradiographic grain counting with the Quantimet 720D image-analysis system. II. Automated grain counting.

A Quantimet 720 Image-Analysis System has been configured and programmed to enumerate silver grains over labeled nuclei in Feulgen-stained autoradiographs. The accuracy and reproducibility of the estimates have been documented in 3H-thymidine (3HTdR)-labeled rat kidney cell cultures. The Quantimet and visual grain count estimates showed excellent correlation over a wide range of counts and was independent of grain density and clustering pattern. One advantage of this approach is that the grain counts can be related to specific cellular structures. The simultaneous measurement of the mean optical density of the grain-free nucleus provides a way of evaluating 3HTdR-absorption effects for valid grain count comparisons. Using a light pen, about 800 cells are measured per hour. The grain count estimates may be made simultaneously with estimates of Feulgen-stained DNA content in the labeled nuclei. This automated technology opens new avenues for critical applications to cell cycle analysis and related problems.

Animals↗
PubMedDate not supplied

Automated data collection and analysis system for MOSFET radiation detectors.

Metal oxide semiconductor field effect transistors (MOSFET) have been used as radiation dosimeters. Because of their small detector size, minimal power requirements, and signal integration characteristics, they offer unique possibilities as real-time dose monitors in radiotherapy. An automated data collection and analysis system for use with MOSFET radiation dosimeters has been designed and built. The objective was to design a system which can acquire and process the MOSFET signals in real time, in any radiation field encountered in radiotherapy. In particular, major problems have been solved arising from the intrinsic drifts of the MOSFET signal during low dose rate measurements. These signal drifts are significant when the MOSFET detector is used in applications such as on-line monitoring of radiation dose delivery in brachytherapy or radioimmunotherapy. The data collection and analysis system includes a portable IBM-compatible personal computer fitted with digital-to-analog and analog-to-digital converter boards. A single-chip programmable current supply is used to power the MOSFET dosimeters. Intrinsic and extrinsic drifts in signal due to ion diffusion and electron tunneling are corrected by deconvolution of the collected data in real time or after data collection. The data acquisition system and signal-processing methodologies are described.

Data Collection↗
PubMed2005

A wide range of protein isoforms in serum and plasma uncovered by a quantitative intact protein analysis system.

We have implemented an orthogonal 3-D intact protein analysis system (IPAS) to quantitatively profile protein differences between human serum and plasma. Reference specimens consisting of pooled Caucasian-American serum, citrate-anticoagulated plasma, and EDTA-anticoagulated plasma were each depleted of six highly abundant proteins, concentrated, and labeled with a different Cy dye (Cy5, Cy3, or Cy2). A mixture consisting of each of the labeled samples was subjected to three dimensions of separation based on charge, hydrophobicity, and molecular mass. Differences in the abundance of proteins between each of the three samples were determined. More than 5000 bands were found to have greater than two-fold difference in intensity between any pair of labeled specimens by quantitative imaging. As expected, some of the differences in band intensities between serum and plasma were attributable to proteins related to coagulation. Interestingly, many proteins were identified in multiple fractions, each exhibiting different pI, hydrophobicity, or molecular mass. This is likely reflective of the expression of different protein isoforms or specific protein cleavage products, as illustrated by complement component 3 precursor and clusterin. IPAS provides a high resolution, high sensitivity, and quantitative approach for the analysis of serum and plasma proteins, and allows assessment of PTMs as a potential source of biomarkers.

Anticoagulants↗
PubMed2001

Microprocessor-based gait analysis system to retrain Trendelenburg gait.

A microprocessor-based gait analysis system is described that uses two electromyogram (EMG) amplifiers, two foot switches and an audio feedback device to allow the retraining of one type of improper gait, where the hip abductors (gluteus medius muscles) are weak on one side of the body, causing the opposite hip to drop during the swing phase of gait (Trendelenburg gait). As the abnormality is strictly on one side of the body in most people, the circuitry is minimised, as gait can be analysed by only comparing muscle activity in the affected gluteus medius muscle with that in the unaffected gluteus medius muscle, through the EMG. Two foot contact switches are used to help assess timing of the step cycle. If gait is different on the two sides of the body, an audio cue directs the patient to correct the abnormality by increasing activity on the affected side. The device is tested on five patients. Trendelenburg gait is reduced by an average of 29 degrees through the use of the device. The average stride length at the beginning of the study is 0.32 +/- 0.3 m. By the end of the study, the stride length is increased to 0.45 +/- 0.2 m for the entire group of five subjects. The speed of gait has increased from 1.6 +/- 0.4 kmh(-1) to 3.1 +/- 0.5km h(-1).

Adult↗
PubMed2004

Combining technologies: a computerized occlusal analysis system synchronized with a computerized electromyography system.

Current advances in computer technologies have afforded dentists precision ways to examine occlusal contacts and muscle function. Recently, two separate computer technologies have been synchronized together, so that an operator can record their separate diagnostic data simultaneously. The two systems are: the T Scan II Occlusal Analysis System and the Biopak Electromyography Recording System. The simultaneous recording and playback capacity of these two computer systems allows the operator to analyze and correlate specific occlusal moments to specific electromyographic changes that result from these occlusal moments. This synchronization provides unparalleled evidence of the effect occlusal contact arrangement has on muscle function. Therefore, the occlusal condition of an inserted dental prosthesis or the occlusal scheme of the natural teeth (before and after corrective occlusal adjustments) can be readily evaluated, documented, and quantified for both, quality of occlusal parameters and muscle activity and the responses to the quality of the occlusal condition. This article describes their synchronization and illustrates their use in performing precision occlusal adjustment procedures on two patients: one who demonstrates occlusal disharmony while exhibiting the signs and symptoms of chronic myofascial pain dysfunction syndrome, and the other who had extensive restorative work accomplished but exhibits occlusal discomfort post-operatively.

Adult↗
PubMed1998

[The ECG&VCG's measurement and analysis system based on PC].

The ECG&VCG's measurement and analysis system based on PC designed by the authors is introduced in this paper. The block diagrams of hardware and software are given as well as characteristics. On the basis of clinic experiments, the relationship between the conventional 12-lead ECG and Frank-VCG is studied with the system. At last a new comprehensive measurement method of the conventional 12-lead ECG and Frank-VCG has been brought forth.

Electrocardiography↗
PubMed1990

Performance of a TV image analysis system as a microdensitometer.

The performance of a TV image analysis system combined with an automated microscope (the Leitz TAS plus) as a microdensitometer and morphometric device was investigated. There was a strict linear correlation (r greater than .99) between the physically defined optical transmission values and the resulting electronic signals from the plumbicon TV camera for the whole area displayed on the monitor. The shading of the optoelectronic system had a coefficient of variation (CV) of 1.42% for measurements in the center of the displayed area, but a CV of 3.55% for measurements over the whole monitor area. Densitometric measurements remained stable 15 minutes after putting the microscope lamp into operation (T less than 0.075%, remeasuring every two minutes). The geometric distortion, measured as different ferret diameters of ideally round latex particles, ranged from +/- 0.5% to +/- 1.0% deviation over the entire displayed area. These results indicate that densitometric and morphometric measurements with this equipment are sufficiently precise and reproducible when performed in the center of the area displayed on the monitor.

Densitometry↗
PubMed2001

A biosensor for detecting changes in cognitive processing based on nonlinear systems analysis.

A new type of biosensor, based on hippocampal slices cultured on multielectrode arrays, and using nonlinear systems analysis for the detection and classification of agents interfering with cognitive function is described. A new method for calculating first and second order kernel was applied for impulse input-spike output datasets and results are presented to show the reliability of the estimations of this parameter. We further decomposed second order kernels as a sum of nine exponentially decaying Laguerre base functions. The data indicate that the method also reliably estimates these nine parameters. Thus, the state of the system can now be described with a set of ten parameters (first order kernel plus nine coefficients of Laguerre base functions) that can be used for detection and classification purposes.

Animals↗
PubMed1997

Reliability of an image analysis system for quantifying the radiographic trabecular pattern.

A reliability evaluation technique was used to examine the reliability of an image analysis system of the trabecular pattern and to determine the contribution of three possible sources of error variance. Two series of radiographs were taken of 14 lumbar vertebral slices (28 radiographs). Every radiograph was placed on a viewing box for digitization four times by a single operator (112 positions of radiographs) and from every position of a radiograph an area of 15 mm x 15 mm was digitized twice (224 samples for analysis). Ten geometrical characteristics of the trabecular pattern were studied and its orientation was analyzed in 12 directions. Reliability was determined by calculating Cronbach's alpha. This design enabled dividing the measurement error (1-alpha) into fractions associated with the X-ray procedure, the operator and the system. Using this reliability evaluation technique, it was found that the orientation variables are more reliable than the geometric variables. It was found that effort to increase the reliability should be directed toward improving the technical procedure of this image analysis system. Also, repeated measurements will increase the reliability. The number of repeated measurements based on a desired reliability can be calculated. This procedure of evaluation gives the opportunity to select a source of error variance which have to be reduced to increase reliability most effectively.

Adult↗
PubMed2006

Computer systems analysis of spaceflight induced changes in left ventricular mass.

Circulatory adaptations resulting in postflight orthostasis have frequently been observed in response to space travel. It has been postulated that a decrement in left ventricular mass (LVM) found after microgravity exposure may be the central component in this cardiovascular deconditioning. However, a physiologic mechanism responsible for these changes in the myocardium has not been determined. In this study, we examined the sequential alterations in echocardiographic measured LVM from preflight to landing day and 3 days into the postflight recovery period. In a previous study in returning astronauts we found a comparative 9.1% reduction in postflight LVM that returned to preflight values by the third day of recovery. This data was further evaluated in a systems analysis approach using a well-established advanced computer model of circulatory functioning. The computer model incorporates the physiologic responses to changes in pressures, flows and hydraulics within the circulatory system as affected by gravitational forces. Myocardial muscle progression to atrophy or hypertrophy in reaction to the circulatory load conditions is also included in the model. The integrative computer analysis suggests that these variations in LVM could be explained by simple fluid shifts known to occur during spaceflight and can reverse within a few days after reentry into earth's gravity. According to model predictions, the reductions in LVM found upon exposure to microgravity are a result of a contraction of the myocardial interstitial fluid space secondary to a loss in the plasma volume. This hypothesis was additionally supported by the published ground-based study in which we followed the alterations in LVM and plasma volume in normal subjects in which hypovolemia was induced by simple dehydration. In the hypovolemic state, plasma volume was reduced in these subjects and was significantly correlated with echocardiographic measurements of LVM. Based on these experimental findings and the performance of the computer systems analysis it appears that reductions in LVM observed after spaceflight may be secondary to fluid exchanges produced by common physiologic mechanisms. Reductions in LVM observed after microgravity exposure have been previously postulated to be a central component of spaceflight-induced cardiovascular deconditioning. However, a recent study has demonstrated a return of astronauts' LVM to preflight values by the third day after landing through uncertain mechanisms. A systems analysis approach using computer simulation techniques allows for a dissection of the complex physiologic control processes and a more detailed examination of the phenomena. From the simulation studies and computer analysis it appears that microgravity induced reductions in LVM may be explained by considering physiologic fluid exchanges rather than cardiac muscle atrophy.

Adult↗
PubMed1988

Microcomputer-based image analysis systems for two-dimensional electrophoresis gels.

The intent of this overview is to provide the readers, especially those who are currently conducting two-dimentional electrophoresis, a basic understanding in the construction and use of microcomputer-based systems for the analysis of protein profiles generated by two-dimensional gel electrophoresis. In addition, a microcomputer-based system, employing fixed-point operations and effective algorithms, has been evaluated. The validity of this system has been demonstrated by using the two-dimensional silver-stained gels and fluorograms derived from the rat prostate. It is concluded that the present system can be used to aid the analysis of two-dimensional electrophoresis gels. An overall consideration of hardware and software components of a computer-based system is briefly discussed.

Computer Systems↗
PubMed2003

Mutation analysis of the RET gene in total intestinal aganglionosis by wave DNA fragment analysis system.

BACKGROUND/PURPOSE: Total intestinal aganglionosis (TIA) extending from the duodenum to the rectum is the most rare form of Hirschprung's disease (HSCR) and usually is fatal. RET is the major gene associated with HSCR, and germline mutations of this gene account for up 50% of familial and up to 15 to 20% of sporadic cases in HSCR. The aim of this study was to investigate DNA variants in the RET gene in TIA patients using the WAVE DNA Fragment Analysis System. METHODS: Genomic DNA was extracted from whole blood samples from 6 patients with TIA. Polymerase chain reaction (PCR) amplification of the 21 exons of RET was performed using published oligonucleotide primers. Heteroduplexes were followed by the WAVE DNA Fragment Analysis System with the DNASep cartridge. RESULTS: WAVE system technology detected 16 variants in the RET gene in the 6 patients with TIA. Three patients had a significant mutation in exon 8, 11, and 15, respectively. Thirteen RET polymorphic variants also were detected in the 6 patients, with L746L variant in exon 13 occurring in 4 patients. CONCLUSIONS: WAVE system technology is an efficient method for the detection of DNA sequence variants. Our findings suggest that not only RET mutations but also RET polymorphic variants may contribute to the occurrence of TIA.

Amino Acid Substitution↗
PubMed1992

Multi centre systems analysis study of primary health care: a study of socio-organizational and human factors.

The information management systems to support health programmes are inadequate. As computers become cheaper and more powerful, their application in the strengthening of the information infrastructure becomes more feasible. However, the high cost of specialized applications software limits their potential, especially in developing countries. A multi-centre systems analysis, (a descriptive study using a questionnaire), was made of District Health Sites in developing countries to analyse whether a common specialized application software design for implementation at a primary health care centre was feasible. Responses to the questionnaires by physicians at the primary health centres were compared between district health sites using contingency tables. Significant inter-site differences in social factors existed, respondents had no prior experience, but with near unanimity (98%) accepted the idea of computer assistance in their work. However, general reservations (31%) and fears (26%) about computer interference in the doctor-patient relationship were expressed. The human factor must be considered in interface design and training before implementation.

Attitude of Health Personnel↗
PubMed2000

A comparison of nefazodone, the cognitive behavioral-analysis system of psychotherapy, and their combination for the treatment of chronic depression.

BACKGROUND: Patients with chronic forms of major depression are difficult to treat, and the relative efficacy of medications and psychotherapy is uncertain. METHODS: We randomly assigned 681 adults with a chronic nonpsychotic major depressive disorder to 12 weeks of outpatient treatment with nefazodone (maximal dose, 600 mg per day), the cognitive behavioral-analysis system of psychotherapy (16 to 20 sessions), or both. At base line, all patients had scores of at least 20 on the 24-item Hamilton Rating Scale for Depression (indicating clinically significant depression). Remission was defined as a score of 8 or less at weeks 10 and 12. For patients who did not have remission, a satisfactory response was defined as a reduction in the score by at least 50 percent from base line and a score of 15 or less. Raters were unaware of the patients' treatment assignments. RESULTS: Of the 681 patients, 662 attended at least one treatment session and were included in the analysis of response. The overall rate of response (both remission and satisfactory response) was 48 percent in both the nefazodone group and in the psychotherapy group, as compared with 73 percent in the combined-treatment group. (P<0.001 for both comparisons). Among the 519 subjects who completed the study, the rates of response were 55 percent in the nefazodone group and 52 percent in the psychotherapy group, as compared with 85 percent in the combined-treatment group (P<0.001 for both comparisons). The rates of withdrawal were similar in the three groups. Adverse events in the nefazodone group were consistent with the known side effects of the drug (e.g., headache, somnolence, dry mouth, nausea, and dizziness). CONCLUSIONS: Although about half of patients with chronic forms of major depression have a response to short-term treatment with either nefazodone or a cognitive behavioral-analysis system of psychotherapy, the combination of the two is significantly more efficacious than either treatment alone.

Adult↗
PubMed1995

[Systems analysis of behavior in conditions of environmental uncertainty].

The paper deals with the organizational features of the functional behavior system under environmental uncertainty conditions (probability training processes, formation of a conditioned reflex at a low intensity of a signal stimulus), as well as with the probability pattern of reinforcement. It shows that the experimental findings are not always in full conformity with the classical behavior act model developed by P. K. Anokhin. The main difficulty is associated with the fact that the above model in its systems content considers a behavioral act merely alone whereas while teaching under great uncertainty conditions, correction of the programme of actions is possible only when many search reactions are simultaneously analyzed. While making a systems analysis of behavioral performance, it is proposed to use a concept of probability decision to alter the programme of action, as well as an idea of memory buffer (results of search reactions). The proposed approach allows one to describe various training conditions, and it operates as the Anokhin model in a specific case. The organizational features of the functional system of behavior under great uncertainty conditions should be taken into account while specifying the informational mechanism responsible for systems quantization of behavior. The above mechanism of the comprehensive evaluation of the positive and negative results of the performed pattern of behavioral acts can be used to explain the discreteness of an action in the programme alteration process when the same quantum of behavior is implemented.

Behavior↗
PubMed1984

Evaluation of an automated image analysis system for counting human tumor colonies.

The Omnicon FAS II image analysis system was applied to counting tumor colonies grown in a soft agar human tumor clonogenic assay with a detailed protocol designed to assess the instrument's sensitivity, specificity, precision, and accuracy. Comparisons of technician and instrument counts were done on a blinded basis. Sensitivity studies (which used metal microspheres) yielded a correlation coefficient (r) of 0.999 between technicians and the counter. A field-by-field analysis of the instrument's specificity for identifying individual objects correctly as tumor colonies rather than artifacts (as identified by the technician) was excellent (r = 0.95). In the precision studies (determined with repeated automated counting of the same samples for five days), the median coefficient of variation was less than 7%. Accuracy was evaluated on cultures of fresh biopsies from 30 human cancers obtained for drug sensitivity testing as well as on a series of tumor cell lines. The correlation between the mean number of colonies counted by the technicians and by the colony counter was greater than 0.91. Similar comparisons of mean percent survival of tumor colony-forming cells after drug exposure between technician and machine were also quite acceptable (r = 0.85). We conclude that the colony counter provided sufficient reliability to be applied to counting human tumor colonies grown in vitro. In addition, the colony counter performed the Petri dish counts ten times faster than experienced technicians and without associated operator fatigue.

Animals↗
PubMed2004

A probabilistic and interactive decision-analysis system for unruptured intracranial aneurysms.

OBJECT: The goal in this study was to develop an interactive, probabilistic decision-analysis system for clinical use in the decision to treat or observe unruptured intracranial aneurysms. Further goals were to enable users of the system to adapt decision-analysis methods to individual patients and to provide a tool for interactive sensitivity analysis. METHODS: A computer program was designed to model the outcomes of treatment and observation of unruptured aneurysms. The user supplies probabilistic estimates of key parameters relating to a specific patient and nominates discount rate and quality of life adjustments. The program uses Monte Carlo discrete-event simulation methods to derive probability estimates of the outcomes of treatment and observation. Results are expressed as summary statistics and graphs. Discounted quality-adjusted life years are graphed using survival methods. Hierarchical simulations are used to enable investigators to perform probabilistic sensitivity analysis for one or multiple parameters simultaneously. The results of sensitivity analysis are expressed in graphs and as the expected value of perfect information. The system can be distributed and updated using the Internet. CONCLUSIONS: Further research is required into the benefits of clinical application of this system. Further research is also required into the optimum level of complexity of the model, into the user interface, and into how clinicians and patients are likely to interpret results. The system is easily adaptable to a range of medical decision analyses.

Confidence Intervals↗