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PubMed1989

Do redundant visual and auditory target variables facilitate control behavior?

The compensatory tracking paradigm has been used extensively in pioneering work on Control Theory, a cybernetic model of behavior. In most studies subjects have been asked to control or maintain at a steady state a single variable or aspect of the stimulus display. The present study utilized three groups of subjects, comparing their performance effectiveness in controlling: (1) a visual stimulus (cursor) versus (2) an auditory stimulus (tone) versus (3) a combined, redundant-cue condition employing both cursor and tone. Freshman volunteers responded to a computer display using a joystick controller; their task was to keep stationary a stimulus that was subject to a smoothed, quasirandom disturbance. Contrary to predictions, subjects in the cursor-alone group performed more effectively than subjects in the combined cursor-tone group. While speculative interpretations are offered, further research is needed to clarify these results.

Adolescent↗
PubMed2006

Quantitative evaluation of macrophage aggregates in brook trout Salvelinus fontinalis and rainbow trout Oncorhynchus mykiss.

Macrophage aggregates (MAs) occur in various organs of fishes, especially the kidney, liver and spleen, and contain melanin, ceroid/lipofuscin and hemosiderin pigments. They have been used as indicators of a number of natural and anthropogenic stressors. Macrophage aggregates occur in salmonids but are poorly organized, irregularly shaped, and are generally smaller than those in derived teleosts. These features complicate quantification, and thus these fishes have seldom been used in studies correlating MAs with environmental stressors. To alleviate these complications, we developed color filtering algorithms for use with the software package ImagePro Plus (Media Cybernetics) that select and quantify pigmented area (i.e. colors ranging from gold to brown to black) in tissue sections. Image analysis results compared well with subjective scoring when tested on brook trout Salvelinus fontinalis and rainbow trout Oncorhynchus mykiss captured from high-elevation lakes or hatcheries. Macrophage aggregate pigments correlated positively with age and negatively with condition factor. Within individual fish, pigmentation correlated positively among organs, suggesting that the kidney, liver or spleen are suitable indicator organs. In age-matched fishes, MA pigments were not different between hatcheries and lakes in the organs examined. Between lakes, differences in pigments were observed in the kidney and spleen, but were not explained by age, condition factor, sex or maturation state. Our results indicate that quantification of the area occupied by MA pigments is an efficient and accurate means of evaluating MAs in salmonid organs and that organ pigmentation correlates with age and condition factor, as seen in studies with more derived fishes.

Age Factors↗
PubMed1993

Prediction of behind-the-wheel driving performance in patients with cerebral brain damage: a discriminant function analysis.

Rehabilitation specialists, particularly occupational therapists, are often involved in evaluating clients' fitness to resume driving after cerebral damage due to head injury or stroke. Their available methods include separate or combined administration of predriver, simulator, and behind-the-wheel evaluations. However, use of these methods without a theoretical model on which to base test selection has yielded some criticism and little research about the effectiveness of these methods in predicting driving performance. Using the authors' Cybernetic Model of Driving as the basis for assessing abilities and behaviors relevant to driving outcome, this study sought to determine the effectiveness of the evaluation methods by discriminant analysis and measurements of sensitivity in predicting behind-the-wheel failures. Comprehensive evaluations of 106 patients revealed that residual deficits in cognition per se did not render a person unfit to drive and underscored the importance of considering behaviors in determining fitness. The methods of evaluation were shown to be relatively sensitive in predicting outcome; off-road and on-road evaluation reached sensitivities of 90% and 92% with the inclusion of behavioral measures. Formulae for predicting outcome based on methods of evaluation are provided and reasons for failures in behind-the-wheel evaluations are discussed.

Adolescent↗
PubMed2006

In vivo perfusion estimation using subharmonic contrast microbubble signals.

OBJECTIVE: The purpose of this study was to quantify perfusion in vivo using contrast-enhanced subharmonic imaging (SHI). METHODS: A modified LOGIQ 9 scanner (GE Healthcare, Milwaukee, WI) operating in gray scale SHI mode was used to measure SHI time-intensity curves in vivo. Four dogs received intravenous contrast bolus injections (dose, 0.1 mL/kg), and renal SHI was performed. After 3 contrast agent injections, a microvascular staining technique based on stable (nonradioactive) isotope-labeled microspheres (BioPhysics Assay Laboratory Inc, Worcester, MA) was used to quantify the degree of perfusion in 8 sections of each kidney. Low perfusion states were induced by ligating surgically exposed segmental renal arteries followed by contrast agent injections and microvascular staining. Digital clips were transferred to a personal computer, and SHI time-intensity curves were acquired in each section using Image-Pro Plus software (Media Cybernetics, Silver Spring, MD). Subharmonic fractional blood volumes were calculated, and the perfusion was estimated from the initial slope of the fractional blood volume uptake averaged over 3 injections. Subharmonic perfusion data were compared with the gold standard (ie, the microspheres) using linear regression analysis. RESULTS: In vivo gray scale SHI clearly showed flow and, thus, perfusion in the kidneys with almost complete suppression of tissue signals. In total, 270 SHI time-intensity curves were acquired, which reduced to 94 perfusion estimates after averaging. Subharmonic perfusion estimates correlated significantly with microsphere results (r = 0.57; P < .0001). The best SHI perfusion estimates occurred for high perfusion states in the anterior of the kidneys (r = 0.73; P = .0001). The corresponding root mean square error was 2.4%. CONCLUSIONS: Subharmonic perfusion estimates have been obtained in vivo. The perfusion estimates were in reasonable to good agreement with a microvascular staining technique.

Albumins↗
PubMed1975

[Morphological aspects of the functional stability of the kidney].

Specific features of the internal architectonics of the secondary kidney have been analyzed from standpoints of main propositions of cybernetics. The high stability of the organ as a biological system is determined by a great number of non-equivalent elements both in the composition of the nephron in the level of coalition of nephrons and in other subsystems. It promotes 1) preservation of a part of neurons under extreme effects, 2) duplication, 3) creation of optimal variants of active functioning coalitions of nephrons, 4) maintenance of optimal regimen of work of the nephron and kidney as a whole. Specialization of cells, their ability to regenerate, control in many levels also contribute to stability. It is supposed that non-equivalence of the elements of subsystems in ontogenesis is sustained by their asynchronous development, while in phylogenesis--by intratissue divergence.

Animals↗
PubMed2000

'Ergonomics in the Nordic European countries--a historical perspective': paper presented at IEA 2000/HFES 2000 Congress. International Ergonomics Association.

The Nordic Ergonomic Society was founded more than 30 years ago to represent Sweden, Finland, Norway and Denmark. Recently Iceland has also been included. The Nordic Ergonomics Society has, to a large extent, traditionally been oriented towards work in the area of physiology, and a large number of its members have backgrounds within such areas as work physiology, physiotherapy and rehabilitation. However, from its inception the society has had members who are experienced within, such fields as work psychology, design, engineering and occupational health and safety. Over the last decade we have also had new members from such areas as work sociology, organizational psychology, leadership, training, information technology and cybernetics. Members have been concerned mainly with the application and practice of ergonomics. The number of members involved in research has also increased over the years. The principal areas of application for such research have been within industry and government.

Ergonomics↗
PubMed2001

Virtual reality as clinical tool: immersion and three-dimensionality in the relationship between patient and therapist.

VR represents the maximum level of evolution in interaction between man and computer systems. In Clinical Psychology, the virtual cyberspace offers a series of powerful and valid applications for diagnosis and therapy. The qualities that make VR software reliable and particularly useful in the practice of assessment and rehabilitation of certain psychopathological dysfunctions emerge with extreme clarity from the specialist literature. VR constitutes a three-dimensional interface that puts the interacting subject in a condition of active exchange with a world re-created via the computer. The possibility of not limiting the paradigm of interaction in a unidirectional sense represents the strong point of the new technology: man is not simply an external observer of pictures or one who passively experiences the reality created by the computer, but on the contrary may actively modify the three-dimensional world in which he is acting, in a condition of complete sensorial immersion. The nature of this exchange means that the subject feels actually present in this new context. The feeling of "actual presence" is perhaps the peculiar characteristic of this tool and is made possible both by the realistic reproduction of the cybernetic environments and by the involvement of all the sensorimotor channels during interaction. In this paper we focus on the characteristics of the new configuration in the relationship between patient and therapist.

Arousal↗
PubMed2001

[Chronic intermittent vagal nerve stimulation--a new therapeutic approach in epilepsy].

BACKGROUND: Vagal nerve stimulation is a new non-pharmacological therapy for patients with refractory epilepsy. Introduced in USA in 1988, the treatment is based on animal experiments demonstrating that intermittent stimulation of the vagal nerve could prevent or reduce the frequency and/or duration of seizures. MATERIAL AND METHODS: At the National Hospital in Norway, 47 therapy-resistant patients have had a vagal nerve stimulator implanted since June 1993. We have used the Neuro-Cybernetic Prosthesis system from Cyberonics, consisting of a programmable pulse generator, a bipolar vagal nerve stimulator lead, a programming wand with accompanying software, and a hand-held magnet. The mean age of the population was 34.4 years (12-70 years). All had a long-standing epilepsy with frequent seizures, 36 (77%) had seizures every day. The majority (89%) had localization-related epilepsy. Mean follow-up time was 2.7 years (0.4-6.5 years). RESULTS: 16 patients (34%) responded to the treatment with > 50% reduction in seizure frequency. No one, however, became seizure free. 20 patients (43%) had no seizure reduction. 24 of the patients (51%) benefited from extra stimulation triggered by the magnet. The stimulation affected several types of seizures; most often a reduction in frequency of secondary generalised tonic-clonic seizures was noted. Hoarseness, coughing and a tingling sensation in the throat were the most frequently reported side effects occurring during stimulation. The patients tended to habituate to these side effects. In 14 patients (30%), the device has been explanted, mostly due to lack of efficacy. INTERPRETATION: Considering the fact that this patient group belongs to the most refractory part of the epilepsy population, the results are regarded as promising and they are in keeping with results from other studies. However, the role of vagal nerve stimulation in the future treatment of epilepsy is still not settled. Several questions remain unanswered, e.g. what are the exact mechanisms of action behind the seizure reducing effect, and which patients are most suitable for this treatment?

Adolescent↗
PubMed1991

German CELSS research with emphasis on the C.E.B.A.S.-project.

In general the German CELSS research program covers both animal and plant systems. In the field of botany a higher plant growth unit is disposed. The construction of a continuous culture device for unicellular algae in long-term multi-generation experiments will start in 1990. In zoology an experimental system for multi-generation experiments, the AQUARACK is already under construction and a running laboratory prototype is surrounded by a wide-spread ground research program. The combination of the algae system with AQUARACK will result in a combined animal-plant system, the "Closed Equilibrated Biological Aquatic System", C.E.B.A.S. which may be the origin for further interdisciplinary research leading to an aquatic plant-animal-CELSS. This research field is closely associated with cybernetical science because the development of the combined systems need simulation processes and highly sophisticated electronical control. A further point in the CELSS program is the study of biological waste management.

Animals↗
PubMed2000

Artificial biospheres as a model for global ecology on planet Earth.

Artificial biospheres of the scale and complexity of Biosphere 2 can only work with coordinated rigorous design at each level of ecology: biospheres, biomes, bioregions, ecosystems, communities, patches, phases, physical-chemical functions, guilds, populations, organisms, and cells (both eucaryotic and procaryotic). This article reviews these theoretical concepts and provides examples of how this structure was applied to the design and development of Biosphere 2. In addition to this ecological engineering design, the addition of humans as inhabitants in the closed system required design of ethnological patterns and of technical and cybernetic systems for meeting specifically human requirements of labor efficiency, climate, nutrition, wastewater recycle, and pure air and water. Ecological levels of biospheric complexity can be directly applied to studies of the Earth's biosphere and, in fact, must be used to understand complex biospheric processes.

Animals↗
PubMed1975

[Indication for jointed matrimonial and familial therapy].

Before psychological treatment is prescribed, one should take into account, with utmost detail and depth, the ways and styles of integration of patients into their family-systems. In order to prove this contention we use the theoretical framework of C. A. Paz and D. Liberman, in connection with criteria of "analyzability". We include three clinical examples in which the need for a model allowing for the systemic character of family organization and marriage partnership is put into evidence. The model is built up starting from developments made in the field of Cybernetics which in turn are based upon Set theory.

Family Therapy↗
PubMedDate not supplied

[Biomedicine or anthropological medicine].

The huge developments in the biological research and in the technics used in other spheres of science (physics, mathematics, chemistry, cybernetics, etc.) have a great influence on the constitution of the actual medical paradigm, as well as other non strictly scientific factors. These external factors are economic, political and cultural ones -such as the pharmaceutical industry and the public health systems, the privatisation of health services, the large amount of professionals, the advances in the medical instruments, etc. The theoritician of the Heidelberg School, called this prevalent model "biomedical" or "natural-scientific", underlying this way the tendance to the biological reductionism in relation to the concept of "illness" thus excluding the subjectivity, the history and the sociability of the patient when dealing with the pain, the inability and the death. Since the middle of XXth Century a serious criticism of this medical paradigm has been raised. This criticism revolved around the so called anthropological or integral model. This article makes a revision of this problem from a historical and epistemological outlook, revisiting some specific features in the psychiatric field.

Anthropology, Physical↗
PubMed2002

[Maximum entropy principle and population genetic equilibrium].

A general mathematic model of population genetic equilibrium was constructed based on the maximum entropy principle. We proved that the maximum entropy probability distribution was equivalent to the Hardy-Weinberg equilibrium law. A population reached genetic equilibrium when the genotype entropy of the population reached the maximal possible value. In information theory, the entropy or the information content is used to measure the uncertainty of a system. In population genetics, we can use entropy to measure the uncertainty of the genotype of a population. The agreement of the maximum entropy principle and the hardy-Weinberg equilibrium law indicated that random crossing is an irreversible process, which increases the genotype entropy of the population, while inbreeding and selection decrease the genotype entropy of the population. In animal or plant breeding, we often use selection and/or inbreeding to decrease the entropy of a population, and use intercrossing to increase the entropy of the population. In this point of view, breeding is actually regulating the entropy of population. By applying the basic principle of informatics in population genetics, we revealed the biological significance of the genotype entropy and demonstrated that we can work over population genetic problems with the principles and methods of informatics and cybernetics.

Animals↗
PubMedDate not supplied

[Computer medical monitors: state-of-the art and perspectives].

The paper shows that the currently available Russian and foreign computer medical monitors (CMMs) may generally solve the simplest tasks of data visualization, recording, and archiving. It is justified that to enhance the "intellectuality" of CMMs, it is necessary to turn to the solution of the problems and tasks of medical monitoring, by using the whole range of methods for biosignal detection and processing, which has been accumulated in modern radio engineering, in the theory of communication, and in engineering and medical cybernetics.

Communication↗
PubMed1975

[The relationship between the structuralism of Levi-Strauss and linguistic methods. An attempt at applying structuralist phonologic models to the study of pathologic language].

The structuralism which is generally accepted as a 'good French' school of thinking, presents in some of its applications the short-time character of fashion in such a way that one often forgets what this philosophy implicates. In this essay, the author intends to show that even though a structural method really exists, one cannot say who exactly is 'the father' of structuralism. But during the long maturity period of thought that resulted in structuralism, one important step has been made in France by Lévi-Strauss who has been using a great number of linguistic concepts, and at the same time has contributed to the consequent progress realized in that discipline. In the light of linguistics and of the works made by Lévi-Strauss some notions are redefined: those of structure, those of oppositions in the systems, those of relations inside one system, and the interactions between 'significant' and 'signifié'. Born from recent research in mathematics and cybernetics, the notion of Model, very fertile in linguistics, is an important element in the Lévi-Strauss structural methodology. With the help of examples taken from phonetics and phonology, the author intends to show how to elaborate a model, of what nature are the links between the observed object and the model, and what can be the applications of that method in the study of pathological languages; the author also intends to show that the main interest in a model of structural type is its explicative and previsional quality. A critical study of the structural analysis makes it possible to show the real contribution of structuralism: the author presents new ways that have been revealed by structuralism and some developments later on favorized by this discipline, mainly in linguistics. Remark. In this study of structuralism, the author places herself on the level with 'method' and not with 'philosophy'.

Child, Preschool↗
PubMedDate not supplied

Computerized quantitative color analysis for histological study of pulmonary fibrosis.

BACKGROUND: Color segmentation is a process through which particular structures can be identified and isolated by the same image according to their color. This may prove particularly useful for the quantification of human pulmonary fibrosis through computerized color segmentation methods applied to trichromic stainings. The aim of this study was to develop and verify a reliable method in order to obtain reproducible parameters of fibrosis using trichromic stainings. MATERIALS AND METHODS: The system used is composed of a PC, hardware and software (Image-Pro Plus 4.1-Media Cybernetics, U.S.A.) for image acquisition and analysis, TV camera and optical microscope. The method requires preliminary software procedures of spatial calibration (micron scale) and setting of color segmentation for quantitative color analysis. Massonstained histological specimens of pulmonary parenchyma, with various degree of fibrosis, were analyzed from 10 cases of different lung diseases. RESULTS: Statistical data of the morphological components identified (space, tissue and fibrosis) support the hypothesis that fibrosis distribution depends on relative amount in the tissue and at the same time attest to the precision of the method. CONCLUSION: This procedure could represent a standard method for histopathological evaluation of tissular damage, with fibrosis outcome, especially in connection with the diagnosis and the seriousness of the damage. This would be extremely useful in both the anatomo-pathological and pathological-forensic fields, to make more objective and reproducible quantitative evaluations of pulmonary damage on autopsy or of bioptic material.

Calibration↗
PubMed1975

[The regulation of cell proliferation by chalones experimental investigations on epidermal hyperplasia (author's transl)].

The pattern of epidermal cell proliferation, following a single application of a hyperplasia inducing agent, can well be interpreted in cybernetic terms. This concept implies that the local concentration of a possible growth inhibiting signal substance should exhibit variations compatible with the changes seen in the cell kinetics of the epidermis. This signal substance has been called the epidermal chalone, first preliminary characterized by Bullough et al. (1964c). Meanwhile a considerable number of other chalone systems have been identified in different organs. From the experimental results a chalone was considered an anti-mitotic substance, which is synthesized within the same tissue on which it specifically acts. It was found not to be species-specific; it reveals a rapid and reversible inhibition by diffusion and passes throughout the tissue and into the blood. Later investigations have exhibited that the epidermal chalone probably consists of at least two separate compounds (proteins), one acting on cells in the postsynthetic, pre-mitotic G 2-phase, the other one on cells in late G 1 (Marks, 1971; Elgjo et al., 1971, 1972). The proliferative behavior of epidermal cells following an application of different irritants was the main subject of the present investigations. All experiments were performed in vivo with hairless mouse epidermis, which was treated with 20-methylcholanthrene (MCA) as carcinogen and crotonoil as cocarcinogen, both dissolved in acetone, and with repeated Scotch tape stripping. Different methods were employed in order to determine epidermal proliferation parameters such as: a. the cytophotometrically measured amount of nucleic deoxyribonucleic acid (DNA) of Feulgen-stained epidermal basal cells, b. the total DNA content of whole epidermis, c. the number of Colcemid(R) arrested metaphases (mitotic rate) in the basal cell layer, d. the incorporation of H3-thymidine into DNA of epidermal basal cells. The number of epidermal basal cells revealing an increased DNA content is significantly lowered for more than 24 hours after MCA and for 12 hours after Crotonoil administration. This effect was not observed after Scotch tape stripping. In all the treated groups this period was followed by a proliferation wave exhibiting more cells with an increased DNA-content during the first 6-10 days after irritation. Only after MCA treatment this higher cell number appeared with a lag phase of 3 to 4 days and coincided with a decrease of the total amount of epidermal DNA. All irritants produced a marked epidermal hyperplasia during the first two weeks after application.

Animals↗