Wyniki wyszukiwania - BazTech

1

Sensory organs and sensing devices

Togawa T.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 6

25-27

EN

Sensory organs and sensing devices are compared in their structure and function, and it is pointed out that the difference in their performances comes from the fact that transmembrane proteins play essential roles in receptor cells: single-molecule action produces output in receptor cells, while mass action is required in sensing devices. It is also pointed out that sensing devices will develop beyond sensory organs when the principles of receptor cell can be copied in sensors.

PL

Przedstawiono porównanie narządów czuciowych i układów czujnikowych ze względu na ich budowę i funkcje, wykazując, że różnica w ich właściwościach wynika głównie z zasadniczej roli, jaką w receptorach odgrywają międzybłonowe białka: w komórkach receptora sygnał jest wywołany działaniem pojedynczej molekuły, podczas gdy układy czujnikowe wymagają wielu działań. Układy te będą stale się rozwijać, a w czujnikach będą odtwarzane zasady, na których opiera się działanie komórek receptorów organów czuciowych.

2

Problems specific to the postreproductive stage of human life in the aging society

Togawa T.

Biocybernetics and Biomedical Engineering

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2007

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Vol. 27, no. 1-2

15-25

EN

The average human life span has significantly increased in majority of developed countries since the latter half of the last century. As a consequence, people can expect to enjoy life for longer than before. However, many problems have emerged in aging societies, making later life more difficult. It is obvious that an aging population causes economic problems such as the difficulty of maintaining pension and medical insurance systems. While such problems are serious and will not be solved easily, more serious and essential problems have emerged because of the changes in social and cultural environments of elderly people. The elderly are now so common that they are not as respected as they once were in former days. They no longer carry the social prestige of wise leaders. Lifestyle changes are occurring so rapidly that the elderly cannot effectively utilize their own experiences, and they experience difficulties adapting to the latest way of life. Cultural maturity, by which the elderly can comfortably spend their later life, might be expected. However, the decline of physical function in the postreproductive stage of life due to aging seriously restricts their activities. In this paper, problems that have emerged in the postreproductive stage of human life in an aging society are discussed from biological and cultural points of view.

3

An approach to scientific understanding of mind by defining a set of all possible contents of consciousness

Togawa T.

Biocybernetics and Biomedical Engineering

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2006

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Vol. 26, no. 1

5-20

EN

The lack of a well-defined concept of consciousness which could be accessible from both the mental and neural aspects is a serious obstruction in understanding the mind. This article is an attempt to introduce a concept of the content space which is definable from the mental side but also relates to neural models. The content space is defined as a set of all possible contents of consciousness, irrespective of the fact whether the each content corresponds to the already-realized conscious experience or not. The conscious event at any moment can be regarded as a result of the past, including all the effects from the outside and the inside of the brain, and the conscious event tends to produce effects on the inside and outside of the brain. This feature can be interpreted as a mental aspect of the neural activity, so that firing of a specific neuron corresponds to a conscious event specific to a certain element of the content space. By introducing the concept of the content space, the neural and mental facets are understood as two different facets of the same event. A specific feature of the contents of the consciousness in humans is that they can be expressed by language. Thus, the linguistic accessibility or the introspection is limited by the content space. According to this assumption, unconscious events cannot be mental but are purely neural. Consequently, no room remains to suspect any mysterious neural instrument in which unconscious mental processes are took place. The self and subjectivity have been shown to be comprehensible without assuming any unknown function.

4

A system for monitoring of sweat secretion from four sweat glands

Foltyński P., Ładyżyński P., Musiał K., Wójcicki J. M., Togawa T.

Biocybernetics and Biomedical Engineering

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2004

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Vol. 24, no. 1

39-48

EN

A method providing monitoring of activity of a single sweat gland by measurement of electric conductivity of perfusion solution has been developed recently. The aim of this project was to design and develop a mesurement system employing the electric conductivity method, which could simultaneously monitor the sweat secretion from four sweat glands. The measurement chamber was developed to use in the measurement system. In vivo measurements using developed system were carried out. Detailed measurement procedure has been presented. The results proved proper operation of the designed system.

5

Measurement of thermal properties of the skin

Togawa T., Otsuka K., Hassan M.

Biocybernetics and Biomedical Engineering

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2002

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Vol. 22, no. 4

55-68

EN

The skin is the boundary between the body and its thermal environment, and heat dissipation from the body depends on the thermal properties of the skin such as thermal conductivity and specific heat as well as emissivity when radiation heat transfer is involved. Such parameters can vary with physiological conditions, especially, thermal conductivity of the skin depends largely on the blood perfusion, and thus in vivo measurement is required. The authors have developed a method of non-contact measurement of emissivity and thermal inertia that is defined as square root of the product of thermal conductivity, density and specific heat. The principle of this method is based on measurement at a transient when a constant heat load is applied abruptly to the skin surface by changing the ambient radiation temperature in step-wise fashion. Emissivity and thermal inertia can be determined from the change in radiation from the skin surface at the transient and the slope of the gradual change of the skin surface temperature. By this principle, imaging of thermal parameters was realized. While accurate measurement of small surface temperature change is required, it was shown that high precision thermography systems could be used for this purpose, and we obtained thermal parameters of the skin under normal and suppressed or enhanced blood perfusion. A convenient calibration method was also proposed in which effective ambient radiation temperature can be computed from simultaneously-measured apparent temperatures of two test plates maintained at different temperatures and having two or more different emissivity areas in each plate. In this paper, various in vivo measurement methods of thermal properties of the skin are reviewed briefly, and the method recently developed and improved by authors was shown in detail.

6

A model of cortical neural network structure

Togawa T., Otsuka K.

Biocybernetics and Biomedical Engineering

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2000

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Vol. 20, no. 3

5-20

EN

A model of cortical neural network structure was proposed in which the single-celI representation hypothesis was introduced. In the model, it was assumed that each information being aware at each moment corresponds to the firing of one specific neuron. It was also assumed that the outputs of such a neuron is coded randomly and connected to other neurons recurrently. It was shown that this structure can be extended to the scaIe of the human cerebral cortex, and that this model is consistent to the relationship between the number of neurons in the entire cortex and the number of synapses on each neuron. To explain memory, the recruitment of unused element, calIed virgin cell, was introduced.

PL

W artykule zaproponowano model sieci neuronowej kory mózgowej. Przyjęto założenie, że informacja zakodowana w sygnale pojawiającym się na wejściu sieci w każdym momencie czasowym jest reprezentowana przez stan jednego elementu sieci. Założono także, że wyjście każdego elementu sieci jest w sposób rekurencyjny połączone z wejściami innych elementów. Wykazano, że taka struktura może być rozszerzona do skali całej kory mózgowej człowieka i że zaproponowany model uwzględnia relacje pomiędzy liczbą komórek nerwowych kory i liczbą synaps na poszczególnych komórkach nerwowych. Aby wyjaśnić mechanizmy pamięci wprowadzono zasadę rekrutacji elementów nieaktywowanych.