Effects of ultra-violet radiation upon involuntary muscle, and the supposed physiological interference of visible rays

It was shown by Adler (1) that involuntary muscle is excited and its tone increased by radiation with ultra-violet rays. The excised frog’s stomach, the bladder and the uterus of the rabbit, and that of the guinea-pig, were suspended by him, each in a suitable salt solution, and excited by the mercury vapour lamp. With a glass screen interposed no result was obtained, the visible and longer ultra-violet rays, e. g ., those longer than about 3200 A. U., having no exciting effect. There may be recalled the old observation of Lambert (1760) that the excised iris of fish and frogs reacts to light by contraction; the visible rays in this case act through the pigment which absorbs them (Steinach, Hertel). Contraction of the pigment-free ventral band of the earth-worm can be produced by ultra-violet, but not by visible rays. On the other hand, visible rays excite the pigmented ventral band of Sipunculus nucleus (Hertel, 2). Probably the nerve plexus is excited by the conversion of visible rays into heat in the pigment cells which absorb these rays.

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Certain pathological effects of ultra-violet radiation on mosquito larvæ and pupæ

Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character ◽

10.1098/rspb.1932.0075 ◽

1932 ◽

Vol 112 (774) ◽

pp. 27-38 ◽

Cited By ~ 2

Keyword(s):

Ovarian Function ◽

Wave Length ◽

Ultra Violet ◽

Mercury Vapour ◽

Mosquito Larvae ◽

Wave Band ◽

Ultra Violet Radiation ◽

Quartz Mercury ◽

Mercury Vapour Lamp ◽

Violet Radiation

In the course of recent work on the possible effect the ultra-violet wave-band may have on the activation of ovarian function in female mosquitoes, it became apparent that mosquito larvae are highly susceptible to a remarkable form of injury by radiations from the unshielded mercury-arc generated by the ordinary Cooper-Hewitt vacuum type of quartz mercury-vapour lamp. This effect upon the larvae has been studied, and an attempt was made (1) to determine the wave-length of the radiations responsible for the injury by means of screens interposed between the lamp and the larvae; and (2) to ascertain the physiological and histological nature of the injury.

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X.—A New Method of Starting Mercury Vapour Apparatus

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s037016460003128x ◽

1914 ◽

Vol 33 ◽

pp. 117-123

Author(s):

John S. Anderson ◽

George B. Burnside

Keyword(s):

Ultra Violet ◽

Electrical Energy ◽

Electrical Current ◽

Public Works ◽

Mercury Vapour ◽

Great Success ◽

Reference Spectrum ◽

Ultra Violet Radiation ◽

Mercury Vapour Lamp ◽

Violet Radiation

The mercury vapour lamp, although very economical in its use of electrical energy, is not employed very extensively at the present day for illuminating purposes, chiefly because the light it emits is not white, but of a greenish hue. Many attempts have been made to produce the deficient red radiation, but these have so far not met with any great success. The lamp, however, is useful as an illuminant where the colour of the light is of no great importance, such as in public works, etc. Further, it is very much used, in the form of rectifiers, for changing alternating to direct electrical current. During the past few years there has been an increasing demand for lamps which are rich in ultra-violet radiation, which is useful for photographic and medical purposes, as, for example, the sterilisation of water, milk, etc. This requirement is met by the mercury vapour lamp, for the ultra-violet spectrum of mercury is particularly intense; lamps used for this purpose must be made of quartz, since ordinary glass absorbs ultra-violet radiation. Then, again, the mercury spectrum is extremely useful in spectroscopic work as a reference spectrum.

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The relation between energy doses of ultra-violet radiation and actinic erythema produced

Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character ◽

10.1098/rspb.1931.0037 ◽

1931 ◽

Vol 108 (757) ◽

pp. 264-270 ◽

Cited By ~ 1

Keyword(s):

Ultra Violet ◽

Radiation Energy ◽

Mercury Vapour ◽

International Unit ◽

Direct Information ◽

Ultra Violet Radiation ◽

Physical Unit ◽

Mercury Vapour Lamp ◽

Violet Radiation

The purpose of the investigation was to ascertain what relation exists between the effect of radiation from a mercury vapour lamp on the skin, as measured by the visible actinic erythema, and the total amount of radiation energy or "dose" received. An international unit of intensity for ultra-violet radiation is under discussion. Whether a physical unit or a biological one based on erythema of the skin be finally adopted, erythema will always remain one of the most important phenomena occurring in actinotherapy and one which gives some direct information regarding the response of an individual to radiation.

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Studies on the Joule Effect in Rubber. I. The Thermal Effect on Stretched Vulcanized Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3539425 ◽

1935 ◽

Vol 8 (2) ◽

pp. 174-176

Author(s):

Yoshio Tanaka ◽

Shū Kambara ◽

Hironosuke Fujita

Keyword(s):

Carbon Black ◽

Thermal Effect ◽

Ultra Violet ◽

Sulfur Compounds ◽

The Other ◽

Joule Effect ◽

Ultra Violet Radiation ◽

Vulcanized Rubber ◽

High Heating ◽

Violet Radiation

Abstract The experiments may be summarized as follows: 1. With an increase in the time of cure, the elongation and heating elongation diminish and the Joule effect increases. 2. An increase in the vulcanization coefficient is followed by a decrease in the elongation and heating elongation and an increase in the Joule effect. The increase in the Joule effect, however, has a limit. 3. An organic accelerator reduces the elongation and heating elongation and increases the Joule effect. 4. The greater the degree of mastication the greater the elongation and the heating elongation and the less the Joule effect. 5. By exposure to ultra-violet radiation, the elongation and heating elongation are increased and the Joule effect decreased. 6. A filler increases the heating elongation and decreases the elongation and the Joule effect. Thus samples with relatively high elongations at a definite tension have relatively high heating elongations and low Joule effects. Such specimens seem to have been affected by the disaggregation and depolymerization of the rubber molecules. The effects of the time of cure, mastication, and exposure to ultra-violet radiation prove this fact. Vulcanization increases the Joule effect, but on the other hand, it is accompanied by a disaggregation and depolymerization of the rubber molecules, so the increase in the Joule effect with the progress of vulcanization has a limit. On vulcanization with an accelerator, the combination of sulfur occurs so rapidly that the increase in the Joule effect is predominant. A filler, such as carbon black, behaves only as a diluent of Joule effect. These results lead to the conclusion that the more highly polymerized rubber molecules and their sulfur compounds seem to be the chief factor in the Joule effect of vulcanized rubber.

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QUANTITATIVE STUDIES ON THE PHOTOLETHAL EFFECTS OF QUARTZ ULTRA-VIOLET RADIATION UPON PARAMECIUM

The Journal of General Physiology ◽

10.1085/jgp.18.4.557 ◽

1935 ◽

Vol 18 (4) ◽

pp. 557-571 ◽

Cited By ~ 25

Author(s):

A. C. Giese ◽

P. A. Leighton

Keyword(s):

Wave Length ◽

Ultra Violet ◽

The Other ◽

Ultra Violet Radiation ◽

Quantitative Studies ◽

Controlled Conditions ◽

Order Of Magnitude ◽

Intense Light ◽

Violet Radiation

Paramecia grown under controlled conditions were irradiated at known intensities of light of wave-lengths 2537, 2654, 2804, 3025, and 3130 A. The approximate absorption of the light by the Parmecia was found to be greatest and of the same order of magnitude at the three shortest wave-lengths, considerably less at 3025, and least at 3130 A. Paramecia did not die when irradiated with high dosages of intense light of wave-length 3130 A. At the other wave-lengths 50 per cent vesiculation occurred when between 1012 and 1013 quanta had been absorbed by a Paramecium. This would indicate that a very large number of molecules in a Paramecium are affected before vesiculation occurs.

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Properties of Higher Polymers in Solution. III. The Action of Ultra-Violet Light on Dissolved Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3539484 ◽

1936 ◽

Vol 9 (4) ◽

pp. 570-572 ◽

Cited By ~ 1

Author(s):

Kurt H. Meyer ◽

Cesare Ferri

Keyword(s):

Physical Properties ◽

Wave Length ◽

Ultra Violet ◽

The Other ◽

Ultra Violet Light ◽

Violet Light ◽

Ultra Violet Radiation ◽

Gutta Percha ◽

Other Hand ◽

Violet Radiation

Abstract The action of ultra-violet radiation on rubber has been the object of a long series of investigations. According to van Rossem, rubber is depolymerized under the action of light. Asano on the other hand thinks that ultra-violet light, is able to bring about either polymerization or depolymerization according to its wave-length. More recently Dogadkin and Pantschenkov have carried out experiments in an atmosphere of nitrogen, during the course of which they have found a strong diminution in the viscosity. From this fact they have concluded that light is able to cause depolymerization and micellar degradation. We have undertaken a study of the action of ultra-violet light on rubber in order to prove whether the double cis-linkages of rubber undergo a transposition into trans-linkages, for numerous instances are known where light causes these cis-trans-transpositions. In the case of rubber, one should obtain, therefore, either a hydrocarbon of the gutta-percha type or, if light causes a sort of cis-trans-equilibrium, a hydrocarbon with double cis-linkages distributed irregularly. In our experiments we were extremely careful to exclude oxygen, since some years ago Henri proved that ultra-violet light activates greatly the oxidation of rubber. On the other hand it is known that oxidation causes a diminution in the length of the chains which modifies considerably the physical properties, for example, the viscosity, and which may mask the effect produced by light.

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Effects of ultra-violet rays upon skeletal muscle

Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character ◽

10.1098/rspb.1927.0003 ◽

1927 ◽

Vol 101 (706) ◽

pp. 24-29 ◽

Cited By ~ 4

Keyword(s):

Skeletal Muscle ◽

Calcium Ions ◽

Ultra Violet ◽

Mercury Vapour ◽

Silk Thread ◽

Nutritive Solution ◽

Involuntary Muscle ◽

Rhythmical Movement ◽

Mercury Vapour Lamp ◽

Nerve System

Leonard Hill and the author have studied the contracture of involuntary muscle produced by radiation with ultra-violet rays, and the author has shown that the presence of calcium ions in the nutritive solution is necessary for this contracture. The mechanism of the contracture produced by these rays is still undetermined. Leo Adler considers it due to changes in the cells of the involuntary muscles, and not to excitation of the vegetative nerve system, which has so great an influence upon rhythmical movement as well as tonus. On the suggestion of Dr. Leonard Hill the author investigated the action of the rays on skeletal muscle, but before doing so studied the effect of exposing various materials (cotton, linen, artificial silk and real silk-thread) to the mercury-vapour lamp. There might be a slight shortening of such fibres, but no remarkable difference in length occurred on irradiation. Tendon or skeletal muscle behaves quite differently from such dead fibres, showing distinct shortening on irradiation.

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