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Gabi N. Waite Stéphane J. P. Egot-Lemaire Walter X. Balcavage 《The Environmentalist》2011,31(2):107-113
Over the past decades, strong evidence has accumulated that low-frequency electromagnetic fields (EMFs) can be useful in treating
human pathologies, such as bone fractures, soft tissue illnesses, and pain. Common strategies for the design of commercial
therapeutic devices are to generate EMFs that simulate body endogenous EMFs, or EMFs that resonate with a particular biological
process, such as the natural motions of ions. We recently came across a biologically active commercial EMF signal that seems
to be different. The signal is generated by summing the fundamental frequencies and harmonics of several periodic base signals
which remain proprietary to the company. When first examined in the time domain, the signal resembled electronic noise; however,
when critically analyzed, the signal is not identical with noise. Rather, it is a highly complex waveform exhibiting a very
wide range of values for the time derivative of the magnetic field density (dB/dt) and a beat frequency in the Extremely Low-Frequency
range. In this paper, we speculate on the mechanism of action of this and similar signals. We consider it less likely that
cells, or cell components, act like filters to extract and couple with individual signals that make up the complex EMF signal.
Consequently, we favor the possibility that with the signal discussed here cells respond to the very complex signal and that
the biological response can be modified by the presence of a beat in the signal, in this case a low-frequency beat. More generally,
this would suggest the hypothesis that biological processes can be regulated by noise-like signals and that the effects of
a noisy signal can be modified by the presence of signal repetition patterns, such as beats. Given the very small energy that
signals like these can transduce into a biological system, biological effects can be expected only when the molecular processes
involved are poised so that the available energy leads to molecular reactions that achieve the activation state for the reaction. 相似文献
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Assessment of Several Test Methods for the Determination of the Anaerobic Biodegradability of Polymers 总被引:1,自引:0,他引:1
Stefan Gartiser Mathis Wallrabenstein Gabi Stiene 《Journal of Polymers and the Environment》1998,6(3):159-173
Anaerobic degradation of eight commercially available biodegradable polymers was compared in two anaerobic tests using digestion sludge, according to ISO 11734 and ASTM D.5210-91. Cotton, polyhydroxybutyrate/hydroxyvalerate copolymer (PHB/PHV), starch blend, thermoplastic cellulose acetate, and cellulose acetate fibers proved to be anaerobically degradable, but only a low extent of degradation was found for polylactide, polyvinylalcohol, and polycaprolactone. Both test methods gave the same overall results, but with the ISO medium, longer lag phases and greater ranges of variation in the results were observed. These effects are presumably due to low concentrations of carbon dioxide in the ISO medium. Carbon dioxide has been demonstrated to be essential for the growth of various anaerobic bacteria, notably homoacetogenic and methanogenic bacteria. 相似文献
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Gabi Drochioiu Karin Popa Doina Humelnicu Manuela Murariu Ion Sandu Alexandru Cecal 《毒物与环境化学》2013,95(2):221-235
A simple approach was carried out to study the effects of various parameters on high performance liquid chromatography (HPLC) performance of microcystin-LR (MC-LR) analysis in samples from some reservoirs and rivers in Taiwan under simulation conditions. Nature of column and its packing affected the instrument sensitivity. Varied column length indicated the longer column enhanced (C18, 5 μm, 4.6 × 150 mm) HPLC performance. Studies on mobile phase found that ratio and concentration of the mobile phase gradient greatly influenced the peak shape, retention time, and optimal conditions of mobile phase were set at acetonitrile and 0.01M ammonium acetate (30:70). Different compounds were added to mobile phase and their contribution to HPLC spectra was reported. Detection limits were carefully measured and reported. These investigations provide simple and important information that may be applied to HPLC performance for microcystin analysis from natural water systems. 相似文献
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Gabi Förtsch Helmut Krinn Gabi Mai Heinz Meinholz Michael Pleikies 《Environmental Sciences Europe》1996,8(5):293-299
Economic regulations on recycling and respective waste disposal legislation will increasingly demand the realization of new waste management concepts. They do not stem from a ministerial goal in itself, but instead offen the enterprizes a chance to develop their own waste disposal strategies with a goal toward the future. In the course of an Intra-company analysis, this waste disposal concept must take the operative organization, the relevant processes and manufacturing techniques, the accumulation of waste in the cost centers as well as the waste disposal and utilization into consideration. Fundamental principles include the environmental regulations applicable to the enterprize in the form of both federal decress and injunctions. An environmental examination report demonstrates the methodical possiblities for stock-taking and makes it possible to identify the measures necessary for improving the operational waste disposal situation. The mandatory data acquisition and a feasible waste monitoring network can be used in the course of environmental management system for making an expert opinion by an independent, reputable environmental verifier. 相似文献
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