A Non-Thermal Effect of Millimeter Wave Radiation on the Puffing of Giant Chromosomes

1983 ◽  
Vol 38 (9-10) ◽  
pp. 883-886 ◽  
Author(s):  
C. Koschnitzke ◽  
F. Kremer ◽  
L. Santo ◽  
P. Quick ◽  
A. Poglitsch
Keyword(s):  
Thermal Effect ◽  
Power Density ◽  
Millimeter Wave ◽  
Thermal Energy ◽  
Temperature Increase ◽  
Secretory Protein ◽  
Wave Radiation ◽  
Thermal Influence ◽  
Acricotopus Lucidus ◽  
Mm Waves

A non-thermal influence of millimeter wave radiation (swept in frequency from 64.1 GHz to 69.1 GHz, sweep­time 6 s, and with stabilized frequencies of 67.200 ± 0.001 GHz and 68.200 ± 0.001 GHz, power density S≦ 6 mW/cm2) on the puffing of giant chromosomes of the midge Acricotopus lucidus (Diptera, Chironomidae) was found. The effect is manifested as a reduction in size of a specific puff that expresses genes for a secretory protein. The non-thermal nature of the effect was proved by experiments in which the sham-exposed sample was warmed up by 2.5 °C which is more than the eight-fold microwave induced temperature increase of ≦0.3°C. Concerning the very low photon energy of mm-waves compared to the thermal energy kT, it seems likely that the coherence of the radiation is essential for the observed effect.

Broadband, Non-Thermal Millimeter-Wave Influence on Giant Chromosomes

1986 ◽  
Vol 41 (3) ◽  
pp. 321-324 ◽  
Author(s):  
Chr. Koschnitzke ◽  
F. Krem ◽  
L. Santo ◽  
A. Poglitsch ◽  
L. Genzel
Keyword(s):  
Millimeter Wave ◽  
Secretory Protein ◽  
Living Systems ◽  
Wave Radiation ◽  
Irradiation Effect ◽  
Safety Standards ◽  
Low Intensity ◽  
Tenfold Increase ◽  
Frequency Regime ◽  
Thermal Influence

A non-thermal influence of low-intensity millimeter-wave radiation on the puffing of giant chromosom es from salivary glands of larvae of the midge A cricotopus lucidus (Diptera, Chironomidae) is reported. The effect is manifested as a strong regression in size of a specific puff that expresses genes for a secretory protein (Fig. 1). While millimeter-wave irradiation leads to an about tenfold increase of the regression probability com pared to controls, simulation of the small microwave-induced temperature increase in the sample does not result in a significant effect, thus confirming the non-thermal nature of the microwave irradiation effect. This finding could be of importance for the understanding of the interaction between microwave radiation and living systems and hence for the establishment of safety standards in that frequency regime.

The Influence of Low-intensity Millimeter-Wave Radiation on the Growth of Cress Roots

1985 ◽  
Vol 40 (5-6) ◽  
pp. 336-343 ◽  
Author(s):  
F. Kremer ◽  
A. Poglitsch ◽  
L. Santo ◽  
D. Sperber ◽  
L. Genzel
Keyword(s):  
Root Growth ◽  
Power Density ◽  
Temperature Increase ◽  
Far Infrared ◽  
Infrared Light ◽  
Lepidium Sativum ◽  
Wave Radiation ◽  
Root Tip ◽  
Low Intensity ◽  
Inhibition Of Growth

Abstract An inhibition of growth in cress roots (Lepidium sativum L.) by irradiation with low-intensity millimeter-waves was found using a computer controlled optical system which is capable of measuring nearly continuously the length of the roots to an accuracy of ± 2 jam. The effect is reversible and, for a power density of 6 mWcm-2, results in completely halting the root growth. It occurs within about 100 s after the onset of irradiation. The microwave-induced temperature increase at the surface of the root tip was found to be less than 0.3 °C at this power density. The effect did not show a sharp frequency dependence however it depended strongly on the polariza­tion of the microwaves with respect to the root orientation. The sensitivity of the root growth to the ambient temperature was examined. Only a weak temperature dependence was found which could not explain the observed effects. However simulating the microwave-induced temperature increase at the surface of the root tip with (incoherent) far-infrared light (λ≥20 μm) resulted in similar effects as with microwaves. Hence one can conclude that the observed effects are primarily caused by the small local irradiation induced thermal gradients across the surface of the root tip.

Simulation of thermal processes in metamaterial millimeter-wave to infrared converter for millimeter-wave imager

2014 ◽  
Vol 05 (supp01) ◽  
pp. 1441009
Author(s):  
Peter S. Zagubisalo ◽  
Andrey G. Paulish ◽  
Sergey A. Kuznetsov
Keyword(s):  
Millimeter Wave ◽  
Dynamic Range ◽  
Wave Radiation ◽  
Thermal Processes ◽  
Image Detector ◽  
Ir Camera ◽  
Emissive Layer ◽  
Time Operation ◽  
Ir Emission ◽  
Mm Waves

The main characteristics of millimeter-wave (MM-wave) image detector were simulated by means of accurate numerical modeling of thermophysical processes in a metamaterial MM-to-IR converter. The converter represents a multilayer structure consisting of an ultra thin resonant metamaterial absorber and a perfect emissive layer. The absorber consists of a dielectric self-supporting film that is metallized from both sides. A micro-pattern is fabricated from one side. Resonant absorption of the MM waves induces the converter heating that yields enhancement of IR emission from the emissive layer. IR emission is detected by IR camera. In this contribution an accurate numerical model for simulation of the thermal processes in the converter structure was created by using COMSOL Multiphysics software. The simulation results are in a good agreement with experimental results that validates the model. The simulation shows that the real-time operation is provided for the converter thickness less than 3 μm and time response can be improved by decreasing of the converter thickness. The energy conversion efficiency of MM waves into IR radiation is over 80%. The converter temperature increase is a linear function of a MM-wave radiation power within three orders of the dynamic range. The blooming effect and ways of its reducing are also discussed. The model allows us to choose the ways of converter structure optimization and improvement of image detector parameters.

The Non-Thermal Effect of Millimeter Wave Radiation on the Puffing of Giant Chromosomes

2006 ◽  
Author(s):  
F. Kremer ◽  
C. Koschnitzke ◽  
L. Santo ◽  
P. Quick ◽  
A. Poglitsch
Keyword(s):  
Thermal Effect ◽  
Millimeter Wave ◽  
Wave Radiation

Analysis of Shadow in Passive Millimeter-Wave Radiation Image

2020 ◽  
Author(s):  
Fangzhou Tang ◽  
Liangqi Gui ◽  
Kaixin Deng ◽  
Ziwei Li ◽  
Ke Chen ◽  
...  
Keyword(s):  
Millimeter Wave ◽  
Wave Radiation
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