Modeling electrical power absorption and thermally-induced biological tissue damage

2013 ◽  
Vol 13 (1) ◽  
pp. 115-121 ◽  
Author(s):  
T. I. Zohdi
Keyword(s):  
Tissue Damage ◽  
Biological Tissue ◽  
Electrical Power ◽  
Power Absorption ◽  
Thermally Induced

scholarly journals Biological Tissue Damage Monitoring Method Based on IMWPE and PNN during HIFU Treatment

Information ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 404
Author(s):  
Bei Liu ◽  
Xian Zhang ◽  
Xiao Zou ◽  
Jing Cao ◽  
Ziqi Peng
Keyword(s):  
Tissue Damage ◽  
Biological Tissue ◽  
Biological Tissues ◽  
Coarse Grained ◽  
Permutation Entropy ◽  
Hifu Treatment ◽  
Monitoring Method ◽  
Multi Scale ◽  
Damage Monitoring ◽  
The Stability

Biological tissue damage monitoring is an indispensable part of high-intensity focused ultrasound (HIFU) treatment. As a nonlinear method, multi-scale permutation entropy (MPE) is widely used in the monitoring of biological tissue. However, the traditional MPE method neglects the amplitude information when calculating the time series complexity, and the stability of MPE is poor due to the defects in the coarse-grained process. In order to solve the above problems, the method of improved coarse-grained multi-scale weighted permutation entropy (IMWPE) is proposed in this paper. Compared with the MPE, the IMWPE method not only includes the amplitude of signal when calculating the signal complexity, but also improves the stability of entropy value. The IMWPE method is applied to the HIFU echo signals during HIFU treatment, and the probabilistic neural network (PNN) is used for monitoring the biological tissue damage. The results show that compared with multi-scale sample entropy (MSE)-PNN and MPE-PNN methods, the proposed IMWPE-PNN method can correctly identify all the normal tissues, and can more effectively identify damaged tissues and denatured tissues. The recognition rate for the three kinds of biological tissues is higher, up to 96.7%. This means that the IMWPE-PNN method can better monitor the status of biological tissue damage during HIFU treatment.

scholarly journals Analyzing the effects of thermal stress on insulator papers by solid-state 13C NMR spectroscopy

Cellulose ◽  
2021 ◽  
Author(s):  
Paul Jusner ◽  
Markus Bacher ◽  
Jonas Simon ◽  
Florian Bausch ◽  
Hajar Khaliliyan ◽  
...  
Keyword(s):  
Thermal Stress ◽  
Nmr Spectroscopy ◽  
Structural Changes ◽  
Electrical Power ◽  
13C Nmr Spectroscopy ◽  
Mas Nmr ◽  
Transformer Oil ◽  
Thermally Induced ◽  
Cellulosic Paper ◽  
Cp Mas Nmr

AbstractMillion tons of cellulosic paper have been used for insulating coils in oil-filled electrical power transformers, thereby assuring the electricity supply for our societies. The high working temperatures in transformers constantly degrade paper insulators throughout their service life of up to 40 years. We approached the structural changes in oil-immersed cellulosic paper samples upon thermal stress in a study that compared unbleached softwood Kraft paper used as insulator paper with pure cotton cellulose paper. The model experiments used a thermal treatment in transformer oil at 170 °C for up to 14 days. The samples were characterized by means of 13C CP/MAS NMR spectroscopy, mainly based on deconvolution of the C4 resonance. An automated, fast, and reproducible C4 resonance deconvolution employing the “Peak Analyzer” tool of OriginPro 2020 (OriginLab Corporation, USA) was developed and used to exploit 13C CP/MAS NMR spectroscopy for the characterization of thermally stressed paper samples. Our results show that thermally induced structural changes depend heavily on the composition of paper, that hornification and coalescence of fibrils take place, and that the allomorph composition of cellulose crystallites is altered under the given conditions. Graphical abstract

FUNDAMENTAL RESEARCH ON RADIOFREQUENCY ABLATION OF RAT BRAIN TISSUE BASED ON NEAR-INFRARED SPECTROSCOPY AND MIE THEORY

2010 ◽  
Vol 03 (03) ◽  
pp. 213-219
Author(s):  
GUANGXIA HU ◽  
ZHIYU QIAN ◽  
TIANMING YANG ◽  
WEITAO LI ◽  
JIERU XIE
Keyword(s):  
Infrared Spectroscopy ◽  
Radiofrequency Ablation ◽  
Near Infrared Spectroscopy ◽  
Biological Tissue ◽  
Near Infrared ◽  
Mie Theory ◽  
Optical Parameters ◽  
Thermally Induced ◽  
Thermal Coagulation ◽  
Fundamental Research

Near-infrared spectroscopy (NIRS) technology and Mie theory are utilized for fundamental research on radiofrequency ablation of biological tissue. Firstly, NIRS is utilized to monitor rats undergoing radiofrequency ablation surgery in real time so as to explore the relationship between reduced scattering coefficient ([Formula: see text]) and the degree of thermally induced tissue coagulation. Then, Mie theory is utilized to analyze the morphological structure change of biological tissue so as to explore the basic mechanism of the change of optical parameters caused by thermally induced tissue coagulation. Results show that there is a close relationship between [Formula: see text] and the degree of thermally induced tissue coagulation; the degree of thermal coagulation can be obtained by the value of [Formula: see text]; when biological tissue thermally coagulates, the average equivalent scattering particle decreases, the particle density increases, and the anisotropy factor decreases.

Advances in Microprobe Analysis Applied to Muscle, Nerve and Gland

1982 ◽  
Vol 40 ◽  
pp. 404-407
Author(s):  
T. E. Hutchinson ◽  
D. E. Johnson ◽  
A. C. Lee ◽  
E. Y. Wang
Keyword(s):  
Biological Tissue ◽  
Microprobe Analysis ◽  
Physiological State ◽  
External Environment ◽  
Physiological Relevance ◽  
Muscle Nerve ◽  
Technique Development

Microprobe analysis of biological tissue is now in the end phase of transition from instrumental and technique development to applications pertinent to questions of physiological relevance. The promise,implicit in early investigative efforts, is being fulfilled to an extent much greater than many had predicted. It would thus seem appropriate to briefly report studies exemplifying this, ∿. In general, the distributions of ions in tissue in a preselected physiological state produced by variations in the external environment is of importance in elucidating the mechanisms of exchange and regulation of these ions.

Morphologies of Nonadherent Al2O3 and Matching Substrate Surfaces

1972 ◽  
Vol 30 ◽  
pp. 524-525
Author(s):  
C. S. Giggins ◽  
J. K. Tien ◽  
B. H. Kear ◽  
F. S. Pettit
Keyword(s):  
Electron Microscopy ◽  
Oxide Scale ◽  
Oxidation Resistance ◽  
Substrate Surface ◽  
Morphological Features ◽  
Thermally Induced ◽  
Oxide Spallation ◽  
Oxidation Resistant ◽  
Induced Stresses ◽  
Substrate Surfaces

The performance of most oxidation resistant alloys and coatings is markedly improved if the oxide scale strongly adheres to the substrate surface. Consequently, in order to develop alloys and coatings with improved oxidation resistance, it has become necessary to determine the conditions that lead to spallation of oxides from the surfaces of alloys. In what follows, the morphological features of nonadherent Al2O3, and the substrate surfaces from which the Al2O3 has spalled, are presented and related to oxide spallation.The Al2O3, scales were developed by oxidizing Fe-25Cr-4Al (w/o) and Ni-rich Ni3 (Al,Ta) alloys in air at 1200°C. These scales spalled from their substrates upon cooling as a result of thermally induced stresses. The scales and the alloy substrate surfaces were then examined by scanning and replication electron microscopy.The Al2O3, scales from the Fe-Cr-Al contained filamentary protrusions at the oxide-gas interface, Fig. 1(a). In addition, nodules of oxide have been developed such that cavities were formed between the oxide and the substrate, Fig. 1(a).

Artifacts caused by dehydration and epoxy embedding in TEM

1991 ◽  
Vol 49 ◽  
pp. 338-339
Author(s):  
Hilton H. Mollenhauer
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Volume Change ◽  
Tissue Damage ◽  
Beam Specimen ◽  
Chemical Fixation ◽  
Resin Impregnation ◽  
Storage Vesicles ◽  
A Cell ◽  
Tissue Shrinkage

Various means have been devised to preserve biological specimens for electron microscopy, the most common being chemical fixation followed by dehydration and resin impregnation. It is intuitive, and has been amply demonstrated, that these manipulations lead to aberrations of many tissue elements. This report deals with three parts of this problem: specimen dehydration, epoxy embedding resins, and electron beam-specimen interactions. However, because of limited space, only a few points can be summarized.Dehydration: Tissue damage, or at least some molecular transitions within the tissue, must occur during passage of a cell or tissue to a nonaqueous state. Most obvious, perhaps, is a loss of lipid, both that which is in the form of storage vesicles and that associated with tissue elements, particularly membranes. Loss of water during dehydration may also lead to tissue shrinkage of 5-70% (volume change) depending on the tissue and dehydrating agent.

Ultrastructure and analytical microprobe analysis of simian lung mite pigments

1986 ◽  
Vol 44 ◽  
pp. 324-325
Author(s):  
R. W. Cole ◽  
J. C. Kim
Keyword(s):  
Biomedical Research ◽  
Tissue Damage ◽  
Microprobe Analysis ◽  
Old World Monkeys ◽  
Old World ◽  
Experimental Animals ◽  
The Past ◽  
Lung Mite ◽  
Mite Infestations ◽  
Cardiopulmonary System

In recent years, non-human primates have become indispensable as experimental animals in many fields of biomedical research. Pharmaceutical and related industries alone use about 2000,000 primates a year. Respiratory mite infestations in lungs of old world monkeys are of particular concern because the resulting tissue damage can directly effect experimental results, especially in those studies involving the cardiopulmonary system. There has been increasing documentation of primate parasitology in the past twenty years.

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