scholarly journals Evaluation of the static magnetic field interactions for a newly developed magnetic ophthalmic implant at 3 Tesla MRI

2018 ◽  
Vol 191 (03) ◽  
pp. 209-215
Author(s):  
Ann-Kathrin Bodenstein ◽  
Matthias Lüpke ◽  
Christian Seiler ◽  
Frank Goblet ◽  
Stephan Nikolic ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Steel Plate ◽  
Deflection Angle ◽  
Silicon Layer ◽  
Metal Plate ◽  
Spatial Gradient ◽  
Single Plate ◽  
The Deflection Angle ◽  
Grade 3

Purpose The purpose of this study is to analyze the static magnetic field interactions for an ophthalmic-magnetic shunt implant with a ferromagnetic steel plate in a thin silicon layer. The plate is used for opening of a valve flap. Ten different sizes of this steel plate were investigated to characterize the relationship between the size of the metal and the magnetic forces of the static magnetic field of a 3.0 T MRI. Materials and Methods The magnetic translation force Fz was quantified by determining the deflection angle using the deflection angle test (ASTM F 2052). The torque was qualitatively estimated by using a 5-point grading scale (0: no torque; + 4: very strong torque) according to Sommer et al. 11. For the visual investigation of the function of the metal plate both prototypes were positioned at the magnetic field’s spatial gradient and at the magnet’s isocenter. The stitches were exposed to the thousandfold of the translational force by a dynamometer. Results The translational force was found to be 10 times greater than the weight of a single plate. The plates were exposed to a high torque (grade 3 to 4). The seams and the tissue withstood more than a thousandfold of the determined translational force. No spontaneous, uncontrolled opening of the valve flap was visible in the MRI, as a result of which the intraocular pressure could decrease considerably. Conclusion Due to the small size of the plates the translational force and the torque will be compensated by the silicon layer and also by the fixation in the eye. Key points:  Citation Format

Antiferromagnetic Conic Refraction of Sound in Hematite

2010 ◽  
Vol 168-169 ◽  
pp. 173-176
Author(s):  
S.A. Migachev ◽  
M.F. Sadykov ◽  
M.M. Shakirzyanov ◽  
D.A. Ivanov
Keyword(s):  
Magnetic Field ◽  
Elastic Waves ◽  
Energy Flow ◽  
Deflection Angle ◽  
Easy Plane ◽  
Magnetoelastic Interaction ◽  
Basis Plane ◽  
Field Dependent ◽  
The Deflection Angle ◽  
The Magnetic Field

In a trigonal easy-plane -Fe2O3 antiferromagnet magnetic-field-dependent conic refraction due to the renormalization of the coefficients of elasticity effective magnetoelastic interaction is experimentally found in addition to the conventional internal conic refraction of the transverse elastic waves propagating along the trigonal C3 axis. It is shown that the deflection angle () of the energy flow from the C3 axis upon the internal conic refraction does not depend on the value of the magnetic field applied in the basis plane (HC3) and is a constant value determined by the correlation of the C14 and C44 coefficients of elasticity. The deflection angle of the energy flow upon the antiferromagnetic conic refraction () increases with increase in the field and tends to the  value at large H values. The obtained results agree well with the theory of this phenomenon in antiferromagnets and support its conclusions.

scholarly journals Nonreciprocal terahertz beam steering based on magneto-optic metagratings

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Zhiyu Tan ◽  
Fei Fan ◽  
Xipu Dong ◽  
Jierong Cheng ◽  
Shengjiang Chang
Keyword(s):  
Magnetic Field ◽  
Dispersion Relation ◽  
Phase Shift ◽  
Large Deflection ◽  
Deflection Angle ◽  
Beam Steering ◽  
Low Loss ◽  
The Deflection Angle ◽  
Gradient Phase ◽  
Great Potential Application

AbstractIn this work, an active nonreciprocal THz beam steering has been proposed based on a transversely magnetized metal/InSb metagrating. The nonreciprocal dispersion relation and phase shift characteristics of the metal/InSb waveguide are investigated in details. A metagrating structure with gradient phase shift has been designed based on the metal/InSb waveguide. Under the external magnetic field (EMF), the THz beam can be changed among 0, +1st, and −1st order of the metagrating. Due to the nonreciprocity of the metal/InSb metagrating, the deflection angle can be controlled by changing the positive and negative directions of the EMF, to realize bilateral symmetric scanning from −67.8° to 67.8° with over 70% diffraction efficiency, and this device also exhibits the nonreciprocal one-way transmission as an isolator with the isolation of 13 dB. This low-loss, large deflection degree, nonreciprocal beam scanner has a great potential application in the THz regime.

Decreased chemotaxis of human peripheral phagocytes exposed to a strong static magnetic field

2004 ◽  
Vol 91 (1) ◽  
pp. 59-65 ◽  
Author(s):  
S Sipka ◽  
I Szöllősi ◽  
Gy Batta ◽  
Gy Szegedi ◽  
Á Illés ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field

Intense Static Magnetic Field Induced Bone Growth in Vivo

1984 ◽  
Vol 3 (1) ◽  
pp. 223-234
Author(s):  
Frank Papatheofanis ◽  
Bill Fapatheofanls ◽  
Robert Ray
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Bone Growth

ABOUT UNIFORMITY OF THE PHENOMENOLOGY AND THE MATHEMATICAL DESCRIPTION OF SO-CALLED « JOINED» ACTION OF HAZARDS AND COMBINED TOXICITY (ON THE EXAMPLE OF A COMBIBATION OF THE FLUORIDE AND THE STATIC MAGNETIC FIELD)

2016 ◽  
pp. 13-20
Author(s):  
B. A. Katsnelson ◽  
M. P. Sutunkova ◽  
N. A. Tsepilov ◽  
V. G. Panov ◽  
A. N. Varaksin ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Point Of View ◽  
Whole Body ◽  
Surface Model ◽  
Combined Toxicity ◽  
Fluoride Solution ◽  
Adverse Action ◽  
Biochemical Indices ◽  
And Control

Sodium fluoride solution was injected i.p. to three groups of rats at a dose equivalent to 0.1 LD50 three times a week up to 18 injections. Two out of these groups and two out of three groups were sham-injected with normal saline and were exposed to the whole body impact of a 25 mT static magnetic field (SMF) for 2 or 4 hr a day, 5 times a week. Following the exposure, various functional and biochemical indices were evaluated along with histological examination and morphometric measurements of the femur in the differently exposed and control rats. The mathematical analysis of the combined effects of the SMF and fluoride based on the a response surface model demonstrated that, in full correspondence with what we had previously found for the combined toxicity of different chemicals, the combined adverse action of a chemical plus a physical agent was characterized by a tipological diversity depending not only on particular effects these types were assessed for but on the dose and effect levels as well. From this point of view, the indices for which at least one statistically significant effect was observed could be classified as identifying (I) mainly single-factor action; (II) additive unidirectional action; (III) synergism (superadditive unidirectional action); (IV) antagonism, including both subadditive unidirectional action and all variants of contradirectional action.

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